public inbox for devel@edk2.groups.io
 help / color / mirror / Atom feed
From: "Nhi Pham" <nhi@os.amperecomputing.com>
To: devel@edk2.groups.io
Cc: Vu Nguyen <vunguyen@os.amperecomputing.com>
Subject: [edk2-platforms][PATCH 13/34] AmpereAltraPkg: Add PciHostBridge driver
Date: Wed,  9 Dec 2020 16:25:10 +0700	[thread overview]
Message-ID: <20201209092531.30867-14-nhi@os.amperecomputing.com> (raw)
In-Reply-To: <20201209092531.30867-1-nhi@os.amperecomputing.com>

From: Vu Nguyen <vunguyen@os.amperecomputing.com>

The purpose of this driver is to produce PciRootBridgeIo and
PciHostBridgeResourceAllocation protocol consumed by PciBus driver.

Signed-off-by: Vu Nguyen <vunguyen@os.amperecomputing.com>
---
 Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf |   56 +
 Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.h      |  441 ++++++
 Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.h    |  554 +++++++
 Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c      | 1414 ++++++++++++++++++
 Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c    | 1558 ++++++++++++++++++++
 5 files changed, 4023 insertions(+)

diff --git a/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf
new file mode 100755
index 000000000000..f56cf30e38d0
--- /dev/null
+++ b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf
@@ -0,0 +1,56 @@
+## @file
+#
+# Copyright (c) 2020, Ampere Computing LLC. All rights reserved.<BR>
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001B
+  BASE_NAME                      = PciHostBridgeDxe
+  FILE_GUID                      = D7ABBD62-2E03-11E8-B467-0ED5F89F718B
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = InitializePciHostBridge
+
+[Sources]
+  PciHostBridge.h
+  PciHostBridge.c
+  PciRootBridgeIo.h
+  PciRootBridgeIo.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  ArmPlatformPkg/ArmPlatformPkg.dec
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  Silicon/Ampere/AmperePkg.dec
+  Silicon/Ampere/AmpereAltraPkg/Ac01Pkg.dec
+
+[LibraryClasses]
+  IoLib
+  UefiDriverEntryPoint
+  UefiBootServicesTableLib
+  DxeServicesTableLib
+  UefiLib
+  MemoryAllocationLib
+  BaseMemoryLib
+  BaseLib
+  DebugLib
+  DevicePathLib
+  PcdLib
+  PcieCoreLib
+  AcpiHelperLib
+
+[Protocols]
+  gEfiPciHostBridgeResourceAllocationProtocolGuid
+  gEfiPciRootBridgeIoProtocolGuid
+  gEfiMetronomeArchProtocolGuid
+  gEfiDevicePathProtocolGuid
+
+[FixedPcd]
+  gArmTokenSpaceGuid.PcdSystemMemoryBase
+
+[Depex]
+  gEfiMetronomeArchProtocolGuid
diff --git a/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.h b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.h
new file mode 100755
index 000000000000..4a3bba95cf7d
--- /dev/null
+++ b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.h
@@ -0,0 +1,441 @@
+/** @file
+
+  Copyright (c) 2020, Ampere Computing LLC. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef _PCI_HOST_BRIDGE_H_
+#define _PCI_HOST_BRIDGE_H_
+
+#include <IndustryStandard/Acpi.h>
+
+#include <Protocol/PciHostBridgeResourceAllocation.h>
+#include <Protocol/PciRootBridgeIo.h>
+#include <Protocol/Metronome.h>
+#include <Protocol/DevicePath.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/DevicePathLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/PciHostBridgeLib.h>
+#include <PciBus.h>
+
+#undef PCIE_PLATFORM_DEBUG
+#undef PCIE_MMIO_DEBUG
+
+#ifdef PCIE_PLATFORM_DEBUG
+#define PCIE_DEBUG(arg...)       DEBUG((DEBUG_INFO,"PCIHostBridge: "));DEBUG((DEBUG_INFO,## arg))
+#else
+#define PCIE_DEBUG(arg...)
+#endif
+
+#ifdef PCIE_MMIO_DEBUG
+#define PCIE_MMIO_DEBUG(arg...)       DEBUG((DEBUG_INFO,"PCIRootBridge: "));DEBUG((DEBUG_INFO,## arg))
+#else
+#define PCIE_MMIO_DEBUG(arg...)
+#endif
+
+#define PCIE_WARN(arg...)        DEBUG((DEBUG_WARN,"PCIHostBridge (WARN): "));DEBUG((DEBUG_WARN,## arg))
+#define PCIE_ERR(arg...)         DEBUG((DEBUG_ERROR,"PCIHostBridge (ERROR): "));DEBUG((DEBUG_ERROR,## arg))
+
+#define PCI_HOST_BRIDGE_SIGNATURE  SIGNATURE_32('e', 'h', 's', 't')
+#define PCI_ROOT_BRIDGE_SIGNATURE  SIGNATURE_32('e', '2', 'p', 'b')
+
+#define PCI_HOST_BRIDGE_FROM_THIS(a) \
+  CR (a, PCI_HOST_BRIDGE_INSTANCE, ResAlloc, PCI_HOST_BRIDGE_SIGNATURE)
+
+#define PCI_RESOURCE_LESS         0xFFFFFFFFFFFFFFFEULL
+
+//
+// Driver Instance Data Macros
+//
+#define ROOT_BRIDGE_FROM_THIS(a) \
+  CR (a, PCI_ROOT_BRIDGE_INSTANCE, RbIo, PCI_ROOT_BRIDGE_SIGNATURE)
+
+#define ROOT_BRIDGE_FROM_LINK(a) \
+  CR (a, PCI_ROOT_BRIDGE_INSTANCE, Link, PCI_ROOT_BRIDGE_SIGNATURE)
+
+//
+// Type of Resource status
+//
+typedef enum {
+  ResNone = 0,
+  ResSubmitted,
+  ResAllocated,
+  ResStatusMax
+} RES_STATUS;
+
+//
+// Struct of Resource Node
+//
+typedef struct {
+  MRES_TYPE         Type;
+  UINT64            Base;
+  UINT64            Length;
+  UINT64            Alignment;
+  RES_STATUS        Status;
+} PCI_RES_NODE;
+
+//
+// Type of PCIE operation
+//
+typedef enum {
+  IoOperation,
+  MemOperation,
+  PciOperation
+} OPERATION_TYPE;
+
+//
+// Struct of Device Mapping
+//
+typedef struct {
+  ACPI_HID_DEVICE_PATH              AcpiDevicePath;
+  EFI_DEVICE_PATH_PROTOCOL          EndDevicePath;
+} EFI_PCI_ROOT_BRIDGE_DEVICE_PATH;
+
+//
+// Struct of Root Bridge Instance
+//
+typedef struct {
+  UINT32                            Signature;
+  LIST_ENTRY                        Link;
+  EFI_HANDLE                        RootBridgeHandle;
+  UINT64                            RootBridgeAttrib;
+  VOID                              *ConfigBuffer;
+  PCI_RES_NODE                      ResAllocNode[rtMaxRes];
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL   RbIo;
+  PCI_ROOT_BRIDGE                   RootBridge;
+} PCI_ROOT_BRIDGE_INSTANCE;
+
+//
+// Struct of Mapping Info
+//
+typedef struct {
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_OPERATION  Operation;
+  UINTN                                      NumberOfBytes;
+  UINTN                                      NumberOfPages;
+  EFI_PHYSICAL_ADDRESS                       HostAddress;
+  EFI_PHYSICAL_ADDRESS                       MappedHostAddress;
+} MAP_INFO;
+
+//
+// Struct of Host Bridge Instance
+//
+typedef struct {
+  UINTN                                             Signature;
+  EFI_HANDLE                                        HostBridgeHandle;
+  UINTN                                             RootBridgeNumber;
+  LIST_ENTRY                                        Head;
+  BOOLEAN                                           ResourceSubmited;
+  BOOLEAN                                           CanRestarted;
+  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL  ResAlloc;
+} PCI_HOST_BRIDGE_INSTANCE;
+
+/**
+   These are the notifications from the PCI bus driver that it is about to enter a certain
+   phase of the PCI enumeration process.
+
+   This member function can be used to notify the host bridge driver to perform specific actions,
+   including any chipset-specific initialization, so that the chipset is ready to enter the next phase.
+   Eight notification points are defined at this time. See belows:
+   EfiPciHostBridgeBeginEnumeration       Resets the host bridge PCI apertures and internal data
+                                          structures. The PCI enumerator should issue this notification
+                                          before starting a fresh enumeration process. Enumeration cannot
+                                          be restarted after sending any other notification such as
+                                          EfiPciHostBridgeBeginBusAllocation.
+   EfiPciHostBridgeBeginBusAllocation     The bus allocation phase is about to begin. No specific action is
+                                          required here. This notification can be used to perform any
+                                          chipset-specific programming.
+   EfiPciHostBridgeEndBusAllocation       The bus allocation and bus programming phase is complete. No
+                                          specific action is required here. This notification can be used to
+                                          perform any chipset-specific programming.
+   EfiPciHostBridgeBeginResourceAllocation
+                                          The resource allocation phase is about to begin. No specific
+                                          action is required here. This notification can be used to perform
+                                          any chipset-specific programming.
+   EfiPciHostBridgeAllocateResources      Allocates resources per previously submitted requests for all the PCI
+                                          root bridges. These resource settings are returned on the next call to
+                                          GetProposedResources(). Before calling NotifyPhase() with a Phase of
+                                          EfiPciHostBridgeAllocateResource, the PCI bus enumerator is responsible
+                                          for gathering I/O and memory requests for
+                                          all the PCI root bridges and submitting these requests using
+                                          SubmitResources(). This function pads the resource amount
+                                          to suit the root bridge hardware, takes care of dependencies between
+                                          the PCI root bridges, and calls the Global Coherency Domain (GCD)
+                                          with the allocation request. In the case of padding, the allocated range
+                                          could be bigger than what was requested.
+   EfiPciHostBridgeSetResources           Programs the host bridge hardware to decode previously allocated
+                                          resources (proposed resources) for all the PCI root bridges. After the
+                                          hardware is programmed, reassigning resources will not be supported.
+                                          The bus settings are not affected.
+   EfiPciHostBridgeFreeResources          Deallocates resources that were previously allocated for all the PCI
+                                          root bridges and resets the I/O and memory apertures to their initial
+                                          state. The bus settings are not affected. If the request to allocate
+                                          resources fails, the PCI enumerator can use this notification to
+                                          deallocate previous resources, adjust the requests, and retry
+                                          allocation.
+   EfiPciHostBridgeEndResourceAllocation  The resource allocation phase is completed. No specific action is
+                                          required here. This notification can be used to perform any chipsetspecific
+                                          programming.
+
+   @param[in] This                The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in] Phase               The phase during enumeration
+
+   @retval EFI_NOT_READY          This phase cannot be entered at this time. For example, this error
+                                  is valid for a Phase of EfiPciHostBridgeAllocateResources if
+                                  SubmitResources() has not been called for one or more
+                                  PCI root bridges before this call
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error. This error is valid
+                                  for a Phase of EfiPciHostBridgeSetResources.
+   @retval EFI_INVALID_PARAMETER  Invalid phase parameter
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+                                  This error is valid for a Phase of EfiPciHostBridgeAllocateResources if the
+                                  previously submitted resource requests cannot be fulfilled or
+                                  were only partially fulfilled.
+   @retval EFI_SUCCESS            The notification was accepted without any errors.
+
+**/
+EFI_STATUS
+EFIAPI
+NotifyPhase (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PHASE    Phase
+  );
+
+/**
+   Return the device handle of the next PCI root bridge that is associated with this Host Bridge.
+
+   This function is called multiple times to retrieve the device handles of all the PCI root bridges that
+   are associated with this PCI host bridge. Each PCI host bridge is associated with one or more PCI
+   root bridges. On each call, the handle that was returned by the previous call is passed into the
+   interface, and on output the interface returns the device handle of the next PCI root bridge. The
+   caller can use the handle to obtain the instance of the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+   for that root bridge. When there are no more PCI root bridges to report, the interface returns
+   EFI_NOT_FOUND. A PCI enumerator must enumerate the PCI root bridges in the order that they
+   are returned by this function.
+   For D945 implementation, there is only one root bridge in PCI host bridge.
+
+   @param[in]       This              The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in, out]  RootBridgeHandle  Returns the device handle of the next PCI root bridge.
+
+   @retval EFI_SUCCESS            If parameter RootBridgeHandle = NULL, then return the first Rootbridge handle of the
+                                  specific Host bridge and return EFI_SUCCESS.
+   @retval EFI_NOT_FOUND          Can not find the any more root bridge in specific host bridge.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not an EFI_HANDLE that was
+                                  returned on a previous call to GetNextRootBridge().
+**/
+EFI_STATUS
+EFIAPI
+GetNextRootBridge (
+   IN       EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+   IN OUT   EFI_HANDLE                                       *RootBridgeHandle
+   );
+
+/**
+   Returns the allocation attributes of a PCI root bridge.
+
+   The function returns the allocation attributes of a specific PCI root bridge. The attributes can vary
+   from one PCI root bridge to another. These attributes are different from the decode-related
+   attributes that are returned by the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.GetAttributes() member function. The
+   RootBridgeHandle parameter is used to specify the instance of the PCI root bridge. The device
+   handles of all the root bridges that are associated with this host bridge must be obtained by calling
+   GetNextRootBridge(). The attributes are static in the sense that they do not change during or
+   after the enumeration process. The hardware may provide mechanisms to change the attributes on
+   the fly, but such changes must be completed before EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL is
+   installed. The permitted values of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ATTRIBUTES are defined in
+   "Related Definitions" below. The caller uses these attributes to combine multiple resource requests.
+   For example, if the flag EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM is set, the PCI bus enumerator needs to
+   include requests for the prefetchable memory in the nonprefetchable memory pool and not request any
+   prefetchable memory.
+      Attribute                                 Description
+   ------------------------------------         ----------------------------------------------------------------------
+   EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM         If this bit is set, then the PCI root bridge does not support separate
+                                                windows for nonprefetchable and prefetchable memory. A PCI bus
+                                                driver needs to include requests for prefetchable memory in the
+                                                nonprefetchable memory pool.
+
+   EFI_PCI_HOST_BRIDGE_MEM64_DECODE             If this bit is set, then the PCI root bridge supports 64-bit memory
+                                                windows. If this bit is not set, the PCI bus driver needs to include
+                                                requests for a 64-bit memory address in the corresponding 32-bit
+                                                memory pool.
+
+   @param[in]   This               The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in]   RootBridgeHandle   The device handle of the PCI root bridge in which the caller is interested. Type
+                                   EFI_HANDLE is defined in InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param[out]  Attributes         The pointer to attribte of root bridge, it is output parameter
+
+   @retval EFI_INVALID_PARAMETER   Attribute pointer is NULL
+   @retval EFI_INVALID_PARAMETER   RootBridgehandle is invalid.
+   @retval EFI_SUCCESS             Success to get attribute of interested root bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+GetAttributes (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT UINT64                                           *Attributes
+  );
+
+/**
+   Sets up the specified PCI root bridge for the bus enumeration process.
+
+   This member function sets up the root bridge for bus enumeration and returns the PCI bus range
+   over which the search should be performed in ACPI 2.0 resource descriptor format.
+
+   @param[in]   This              The EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ PROTOCOL instance.
+   @param[in]   RootBridgeHandle  The PCI Root Bridge to be set up.
+   @param[out]  Configuration     Pointer to the pointer to the PCI bus resource descriptor.
+
+   @retval EFI_INVALID_PARAMETER Invalid Root bridge's handle
+   @retval EFI_OUT_OF_RESOURCES  Fail to allocate ACPI resource descriptor tag.
+   @retval EFI_SUCCESS           Sucess to allocate ACPI resource descriptor.
+
+**/
+EFI_STATUS
+EFIAPI
+StartBusEnumeration (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT VOID                                             **Configuration
+  );
+
+/**
+   Programs the PCI root bridge hardware so that it decodes the specified PCI bus range.
+
+   This member function programs the specified PCI root bridge to decode the bus range that is
+   specified by the input parameter Configuration.
+   The bus range information is specified in terms of the ACPI 2.0 resource descriptor format.
+
+   @param[in] This              The EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ PROTOCOL instance
+   @param[in] RootBridgeHandle  The PCI Root Bridge whose bus range is to be programmed
+   @param[in] Configuration     The pointer to the PCI bus resource descriptor
+
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER  Configuration is NULL.
+   @retval EFI_INVALID_PARAMETER  Configuration does not point to a valid ACPI 2.0 resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration does not include a valid ACPI 2.0 bus resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration includes valid ACPI 2.0 resource descriptors other than
+                                  bus descriptors.
+   @retval EFI_INVALID_PARAMETER  Configuration contains one or more invalid ACPI resource descriptors.
+   @retval EFI_INVALID_PARAMETER  "Address Range Minimum" is invalid for this root bridge.
+   @retval EFI_INVALID_PARAMETER  "Address Range Length" is invalid for this root bridge.
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error.
+   @retval EFI_SUCCESS            The bus range for the PCI root bridge was programmed.
+
+**/
+EFI_STATUS
+EFIAPI
+SetBusNumbers (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_HANDLE                                       RootBridgeHandle,
+  IN VOID                                             *Configuration
+  );
+
+/**
+   Submits the I/O and memory resource requirements for the specified PCI root bridge.
+
+   This function is used to submit all the I/O and memory resources that are required by the specified
+   PCI root bridge. The input parameter Configuration is used to specify the following:
+   - The various types of resources that are required
+   - The associated lengths in terms of ACPI 2.0 resource descriptor format
+
+   @param[in] This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param[in] RootBridgeHandle  The PCI root bridge whose I/O and memory resource requirements are being submitted.
+   @param[in] Configuration     The pointer to the PCI I/O and PCI memory resource descriptor.
+
+   @retval EFI_SUCCESS            The I/O and memory resource requests for a PCI root bridge were accepted.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER  Configuration is NULL.
+   @retval EFI_INVALID_PARAMETER  Configuration does not point to a valid ACPI 2.0 resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration includes requests for one or more resource types that are
+                                  not supported by this PCI root bridge. This error will happen if the caller
+                                  did not combine resources according to Attributes that were returned by
+                                  GetAllocAttributes().
+   @retval EFI_INVALID_PARAMETER  Address Range Maximum" is invalid.
+   @retval EFI_INVALID_PARAMETER  "Address Range Length" is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  "Address Space Granularity" is invalid for this PCI root bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+SubmitResources (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_HANDLE                                       RootBridgeHandle,
+  IN VOID                                             *Configuration
+  );
+
+/**
+   Returns the proposed resource settings for the specified PCI root bridge.
+
+   This member function returns the proposed resource settings for the specified PCI root bridge. The
+   proposed resource settings are prepared when NotifyPhase() is called with a Phase of
+   EfiPciHostBridgeAllocateResources. The output parameter Configuration
+   specifies the following:
+   - The various types of resources, excluding bus resources, that are allocated
+   - The associated lengths in terms of ACPI 2.0 resource descriptor format
+
+   @param[in]  This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param[in]  RootBridgeHandle  The PCI root bridge handle. Type EFI_HANDLE is defined in InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param[out] Configuration     The pointer to the pointer to the PCI I/O and memory resource descriptor.
+
+   @retval EFI_SUCCESS            The requested parameters were returned.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProposedResources (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT VOID                                             **Configuration
+  );
+
+/**
+   Provides the hooks from the PCI bus driver to every PCI controller (device/function) at various
+   stages of the PCI enumeration process that allow the host bridge driver to preinitialize individual
+   PCI controllers before enumeration.
+
+   This function is called during the PCI enumeration process. No specific action is expected from this
+   member function. It allows the host bridge driver to preinitialize individual PCI controllers before
+   enumeration.
+
+   @param This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param RootBridgeHandle  The associated PCI root bridge handle. Type EFI_HANDLE is defined in
+                            InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param PciAddress        The address of the PCI device on the PCI bus. This address can be passed to the
+                            EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL member functions to access the PCI
+                            configuration space of the device. See Table 12-1 in the UEFI 2.0 Specification for
+                            the definition of EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS.
+   @param Phase             The phase of the PCI device enumeration.
+
+   @retval EFI_SUCCESS              The requested parameters were returned.
+   @retval EFI_INVALID_PARAMETER    RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER    Phase is not a valid phase that is defined in
+                                    EFI_PCI_CONTROLLER_RESOURCE_ALLOCATION_PHASE.
+   @retval EFI_DEVICE_ERROR         Programming failed due to a hardware error. The PCI enumerator should
+                                    not enumerate this device, including its child devices if it is a PCI-to-PCI
+                                    bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+PreprocessController (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL  *This,
+  IN  EFI_HANDLE                                        RootBridgeHandle,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS       PciAddress,
+  IN  EFI_PCI_CONTROLLER_RESOURCE_ALLOCATION_PHASE      Phase
+  );
+
+#endif /* _PCI_HOST_BRIDGE_H_ */
diff --git a/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.h b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.h
new file mode 100755
index 000000000000..1bbed7009a47
--- /dev/null
+++ b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.h
@@ -0,0 +1,554 @@
+/** @file
+
+  Copyright (c) 2020, Ampere Computing LLC. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef _PCI_ROOT_BRIDGE_IO_H_
+#define _PCI_ROOT_BRIDGE_IO_H_
+
+#include <Library/PciLib.h>
+#include <IndustryStandard/Pci22.h>
+
+/**
+   Polls an address in memory mapped I/O space until an exit condition is met, or
+   a timeout occurs.
+
+   This function provides a standard way to poll a PCI memory location. A PCI memory read
+   operation is performed at the PCI memory address specified by Address for the width specified
+   by Width. The result of this PCI memory read operation is stored in Result. This PCI memory
+   read operation is repeated until either a timeout of Delay 100 ns units has expired, or (Result &
+   Mask) is equal to Value.
+
+   @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width     Signifies the width of the memory operations.
+   @param[in]   Address   The base address of the memory operations. The caller is
+   responsible for aligning Address if required.
+   @param[in]   Mask      Mask used for the polling criteria. Bytes above Width in Mask
+   are ignored. The bits in the bytes below Width which are zero in
+   Mask are ignored when polling the memory address.
+   @param[in]   Value     The comparison value used for the polling exit criteria.
+   @param[in]   Delay     The number of 100 ns units to poll. Note that timer available may
+   be of poorer granularity.
+   @param[out]  Result    Pointer to the last value read from the memory location.
+
+   @retval EFI_SUCCESS            The last data returned from the access matched the poll exit criteria.
+   @retval EFI_INVALID_PARAMETER  Width is invalid.
+   @retval EFI_INVALID_PARAMETER  Result is NULL.
+   @retval EFI_TIMEOUT            Delay expired before a match occurred.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPollMem (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN  UINT64                                 Address,
+  IN  UINT64                                 Mask,
+  IN  UINT64                                 Value,
+  IN  UINT64                                 Delay,
+  OUT UINT64                                 *Result
+  );
+
+/**
+   Reads from the I/O space of a PCI Root Bridge. Returns when either the polling exit criteria is
+   satisfied or after a defined duration.
+
+   This function provides a standard way to poll a PCI I/O location. A PCI I/O read operation is
+   performed at the PCI I/O address specified by Address for the width specified by Width.
+   The result of this PCI I/O read operation is stored in Result. This PCI I/O read operation is
+   repeated until either a timeout of Delay 100 ns units has expired, or (Result & Mask) is equal
+   to Value.
+
+   @param[in] This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in] Width     Signifies the width of the I/O operations.
+   @param[in] Address   The base address of the I/O operations. The caller is responsible
+   for aligning Address if required.
+   @param[in] Mask      Mask used for the polling criteria. Bytes above Width in Mask
+   are ignored. The bits in the bytes below Width which are zero in
+   Mask are ignored when polling the I/O address.
+   @param[in] Value     The comparison value used for the polling exit criteria.
+   @param[in] Delay     The number of 100 ns units to poll. Note that timer available may
+   be of poorer granularity.
+   @param[out] Result   Pointer to the last value read from the memory location.
+
+   @retval EFI_SUCCESS            The last data returned from the access matched the poll exit criteria.
+   @retval EFI_INVALID_PARAMETER  Width is invalid.
+   @retval EFI_INVALID_PARAMETER  Result is NULL.
+   @retval EFI_TIMEOUT            Delay expired before a match occurred.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPollIo (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN  UINT64                                 Address,
+  IN  UINT64                                 Mask,
+  IN  UINT64                                 Value,
+  IN  UINT64                                 Delay,
+  OUT UINT64                                 *Result
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in the PCI root bridge memory space.
+
+   The Mem.Read(), and Mem.Write() functions enable a driver to access PCI controller
+   registers in the PCI root bridge memory space.
+   The memory operations are carried out exactly as requested. The caller is responsible for satisfying
+   any alignment and memory width restrictions that a PCI Root Bridge on a platform might require.
+
+   @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width     Signifies the width of the memory operation.
+   @param[in]   Address   The base address of the memory operation. The caller is
+   responsible for aligning the Address if required.
+   @param[in]   Count     The number of memory operations to perform. Bytes moved is
+   Width size * Count, starting at Address.
+   @param[out]  Buffer    For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMemRead (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN  UINT64                                 Address,
+  IN  UINTN                                  Count,
+  OUT VOID                                   *Buffer
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in the PCI root bridge memory space.
+
+   The Mem.Read(), and Mem.Write() functions enable a driver to access PCI controller
+   registers in the PCI root bridge memory space.
+   The memory operations are carried out exactly as requested. The caller is responsible for satisfying
+   any alignment and memory width restrictions that a PCI Root Bridge on a platform might require.
+
+   @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width     Signifies the width of the memory operation.
+   @param[in]   Address   The base address of the memory operation. The caller is
+   responsible for aligning the Address if required.
+   @param[in]   Count     The number of memory operations to perform. Bytes moved is
+   Width size * Count, starting at Address.
+   @param[in]   Buffer    For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMemWrite (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  IN     VOID                                   *Buffer
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in the PCI root bridge I/O space.
+
+   @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width       Signifies the width of the memory operations.
+   @param[in]   UserAddress The base address of the I/O operation. The caller is responsible for
+   aligning the Address if required.
+   @param[in]   Count       The number of I/O operations to perform. Bytes moved is Width
+   size * Count, starting at Address.
+   @param[out]  UserBuffer  For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS              The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER    Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER    Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoIoRead (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 UserAddress,
+  IN     UINTN                                  Count,
+  OUT    VOID                                   *UserBuffer
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in the PCI root bridge I/O space.
+
+   @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width       Signifies the width of the memory operations.
+   @param[in]   UserAddress The base address of the I/O operation. The caller is responsible for
+   aligning the Address if required.
+   @param[in]   Count       The number of I/O operations to perform. Bytes moved is Width
+   size * Count, starting at Address.
+   @param[in]   UserBuffer  For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS              The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER    Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER    Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoIoWrite (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 UserAddress,
+  IN     UINTN                                  Count,
+  IN     VOID                                   *UserBuffer
+  );
+
+/**
+   Enables a PCI driver to copy one region of PCI root bridge memory space to another region of PCI
+   root bridge memory space.
+
+   The CopyMem() function enables a PCI driver to copy one region of PCI root bridge memory
+   space to another region of PCI root bridge memory space. This is especially useful for video scroll
+   operation on a memory mapped video buffer.
+   The memory operations are carried out exactly as requested. The caller is responsible for satisfying
+   any alignment and memory width restrictions that a PCI root bridge on a platform might require.
+
+   @param[in] This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL instance.
+   @param[in] Width       Signifies the width of the memory operations.
+   @param[in] DestAddress The destination address of the memory operation. The caller is
+   responsible for aligning the DestAddress if required.
+   @param[in] SrcAddress  The source address of the memory operation. The caller is
+   responsible for aligning the SrcAddress if required.
+   @param[in] Count       The number of memory operations to perform. Bytes moved is
+   Width size * Count, starting at DestAddress and SrcAddress.
+
+   @retval  EFI_SUCCESS             The data was copied from one memory region to another memory region.
+   @retval  EFI_INVALID_PARAMETER   Width is invalid for this PCI root bridge.
+   @retval  EFI_OUT_OF_RESOURCES    The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoCopyMem (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 DestAddress,
+  IN     UINT64                                 SrcAddress,
+  IN     UINTN                                  Count
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in a PCI root bridge's configuration space.
+
+   The Pci.Read() and Pci.Write() functions enable a driver to access PCI configuration
+   registers for a PCI controller.
+   The PCI Configuration operations are carried out exactly as requested. The caller is responsible for
+   any alignment and PCI configuration width issues that a PCI Root Bridge on a platform might
+   require.
+
+   @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width     Signifies the width of the memory operations.
+   @param[in]   Address   The address within the PCI configuration space for the PCI controller.
+   @param[in]   Count     The number of PCI configuration operations to perform. Bytes
+   moved is Width size * Count, starting at Address.
+   @param[out]  Buffer    For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPciRead (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  OUT    VOID                                   *Buffer
+  );
+
+/**
+   Enables a PCI driver to access PCI controller registers in a PCI root bridge's configuration space.
+
+   The Pci.Read() and Pci.Write() functions enable a driver to access PCI configuration
+   registers for a PCI controller.
+   The PCI Configuration operations are carried out exactly as requested. The caller is responsible for
+   any alignment and PCI configuration width issues that a PCI Root Bridge on a platform might
+   require.
+
+   @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Width     Signifies the width of the memory operations.
+   @param[in]   Address   The address within the PCI configuration space for the PCI controller.
+   @param[in]   Count     The number of PCI configuration operations to perform. Bytes
+   moved is Width size * Count, starting at Address.
+   @param[in]   Buffer    For read operations, the destination buffer to store the results. For
+   write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPciWrite (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  IN     VOID                                   *Buffer
+  );
+
+/**
+   Provides the PCI controller-specific addresses required to access system memory from a
+   DMA bus master.
+
+   The Map() function provides the PCI controller specific addresses needed to access system
+   memory. This function is used to map system memory for PCI bus master DMA accesses.
+
+   @param[in]       This            A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]       Operation       Indicates if the bus master is going to read or write to system memory.
+   @param[in]       HostAddress     The system memory address to map to the PCI controller.
+   @param[in, out]  NumberOfBytes   On input the number of bytes to map. On output the number of bytes that were mapped.
+   @param[out]      DeviceAddress   The resulting map address for the bus master PCI controller to use
+   to access the system memory's HostAddress.
+   @param[out]      Mapping         The value to pass to Unmap() when the bus master DMA operation is complete.
+
+   @retval EFI_SUCCESS            The range was mapped for the returned NumberOfBytes.
+   @retval EFI_INVALID_PARAMETER  Operation is invalid.
+   @retval EFI_INVALID_PARAMETER  HostAddress is NULL.
+   @retval EFI_INVALID_PARAMETER  NumberOfBytes is NULL.
+   @retval EFI_INVALID_PARAMETER  DeviceAddress is NULL.
+   @retval EFI_INVALID_PARAMETER  Mapping is NULL.
+   @retval EFI_UNSUPPORTED        The HostAddress cannot be mapped as a common buffer.
+   @retval EFI_DEVICE_ERROR       The system hardware could not map the requested address.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMap (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL            *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_OPERATION  Operation,
+  IN     VOID                                       *HostAddress,
+  IN OUT UINTN                                      *NumberOfBytes,
+  OUT    EFI_PHYSICAL_ADDRESS                       *DeviceAddress,
+  OUT    VOID                                       **Mapping
+  );
+
+/**
+   Completes the Map() operation and releases any corresponding resources.
+
+   The Unmap() function completes the Map() operation and releases any corresponding resources.
+   If the operation was an EfiPciOperationBusMasterWrite or
+   EfiPciOperationBusMasterWrite64, the data is committed to the target system memory.
+   Any resources used for the mapping are freed.
+
+   @param[in] This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in] Mapping   The mapping value returned from Map().
+
+   @retval EFI_SUCCESS            The range was unmapped.
+   @retval EFI_INVALID_PARAMETER  Mapping is not a value that was returned by Map().
+   @retval EFI_DEVICE_ERROR       The data was not committed to the target system memory.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoUnmap (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN  VOID                             *Mapping
+  );
+
+/**
+   Allocates pages that are suitable for an EfiPciOperationBusMasterCommonBuffer or
+   EfiPciOperationBusMasterCommonBuffer64 mapping.
+
+   @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param Type        This parameter is not used and must be ignored.
+   @param MemoryType  The type of memory to allocate, EfiBootServicesData or EfiRuntimeServicesData.
+   @param Pages       The number of pages to allocate.
+   @param HostAddress A pointer to store the base system memory address of the allocated range.
+   @param Attributes  The requested bit mask of attributes for the allocated range. Only
+   the attributes EFI_PCI_ATTRIBUTE_MEMORY_WRITE_COMBINE, EFI_PCI_ATTRIBUTE_MEMORY_CACHED,
+   and EFI_PCI_ATTRIBUTE_DUAL_ADDRESS_CYCLE may be used with this function.
+
+   @retval EFI_SUCCESS            The requested memory pages were allocated.
+   @retval EFI_INVALID_PARAMETER  MemoryType is invalid.
+   @retval EFI_INVALID_PARAMETER  HostAddress is NULL.
+   @retval EFI_UNSUPPORTED        Attributes is unsupported. The only legal attribute bits are
+   MEMORY_WRITE_COMBINE, MEMORY_CACHED, and DUAL_ADDRESS_CYCLE.
+   @retval EFI_OUT_OF_RESOURCES   The memory pages could not be allocated.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoAllocateBuffer (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN  EFI_ALLOCATE_TYPE                Type,
+  IN  EFI_MEMORY_TYPE                  MemoryType,
+  IN  UINTN                            Pages,
+  OUT VOID                             **HostAddress,
+  IN  UINT64                           Attributes
+  );
+
+/**
+   Frees memory that was allocated with AllocateBuffer().
+
+   The FreeBuffer() function frees memory that was allocated with AllocateBuffer().
+
+   @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param Pages       The number of pages to free.
+   @param HostAddress The base system memory address of the allocated range.
+
+   @retval EFI_SUCCESS            The requested memory pages were freed.
+   @retval EFI_INVALID_PARAMETER  The memory range specified by HostAddress and Pages
+   was not allocated with AllocateBuffer().
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoFreeBuffer (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN  UINTN                            Pages,
+  OUT VOID                             *HostAddress
+  );
+
+/**
+   Flushes all PCI posted write transactions from a PCI host bridge to system memory.
+
+   The Flush() function flushes any PCI posted write transactions from a PCI host bridge to system
+   memory. Posted write transactions are generated by PCI bus masters when they perform write
+   transactions to target addresses in system memory.
+   This function does not flush posted write transactions from any PCI bridges. A PCI controller
+   specific action must be taken to guarantee that the posted write transactions have been flushed from
+   the PCI controller and from all the PCI bridges into the PCI host bridge. This is typically done with
+   a PCI read transaction from the PCI controller prior to calling Flush().
+
+   @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+
+   @retval EFI_SUCCESS        The PCI posted write transactions were flushed from the PCI host
+   bridge to system memory.
+   @retval EFI_DEVICE_ERROR   The PCI posted write transactions were not flushed from the PCI
+   host bridge due to a hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoFlush (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This
+  );
+
+/**
+   Gets the attributes that a PCI root bridge supports setting with SetAttributes(), and the
+   attributes that a PCI root bridge is currently using.
+
+   The GetAttributes() function returns the mask of attributes that this PCI root bridge supports
+   and the mask of attributes that the PCI root bridge is currently using.
+
+   @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param Supported   A pointer to the mask of attributes that this PCI root bridge
+   supports setting with SetAttributes().
+   @param Attributes  A pointer to the mask of attributes that this PCI root bridge is
+   currently using.
+
+   @retval  EFI_SUCCESS           If Supports is not NULL, then the attributes that the PCI root
+   bridge supports is returned in Supports. If Attributes is
+   not NULL, then the attributes that the PCI root bridge is currently
+   using is returned in Attributes.
+   @retval  EFI_INVALID_PARAMETER Both Supports and Attributes are NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoGetAttributes (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  OUT UINT64                           *Supported,
+  OUT UINT64                           *Attributes
+  );
+
+/**
+   Sets attributes for a resource range on a PCI root bridge.
+
+   The SetAttributes() function sets the attributes specified in Attributes for the PCI root
+   bridge on the resource range specified by ResourceBase and ResourceLength. Since the
+   granularity of setting these attributes may vary from resource type to resource type, and from
+   platform to platform, the actual resource range and the one passed in by the caller may differ. As a
+   result, this function may set the attributes specified by Attributes on a larger resource range
+   than the caller requested. The actual range is returned in ResourceBase and
+   ResourceLength. The caller is responsible for verifying that the actual range for which the
+   attributes were set is acceptable.
+
+   @param[in]       This            A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]       Attributes      The mask of attributes to set. If the attribute bit
+   MEMORY_WRITE_COMBINE, MEMORY_CACHED, or
+   MEMORY_DISABLE is set, then the resource range is specified by
+   ResourceBase and ResourceLength. If
+   MEMORY_WRITE_COMBINE, MEMORY_CACHED, and
+   MEMORY_DISABLE are not set, then ResourceBase and
+   ResourceLength are ignored, and may be NULL.
+   @param[in, out]  ResourceBase    A pointer to the base address of the resource range to be modified
+   by the attributes specified by Attributes.
+   @param[in, out]  ResourceLength  A pointer to the length of the resource range to be modified by the
+   attributes specified by Attributes.
+
+   @retval  EFI_SUCCESS     The current configuration of this PCI root bridge was returned in Resources.
+   @retval  EFI_UNSUPPORTED The current configuration of this PCI root bridge could not be retrieved.
+   @retval  EFI_INVALID_PARAMETER Invalid pointer of EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoSetAttributes (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN     UINT64                           Attributes,
+  IN OUT UINT64                           *ResourceBase,
+  IN OUT UINT64                           *ResourceLength
+  );
+
+/**
+   Retrieves the current resource settings of this PCI root bridge in the form of a set of ACPI 2.0
+   resource descriptors.
+
+   There are only two resource descriptor types from the ACPI Specification that may be used to
+   describe the current resources allocated to a PCI root bridge. These are the QWORD Address
+   Space Descriptor (ACPI 2.0 Section 6.4.3.5.1), and the End Tag (ACPI 2.0 Section 6.4.2.8). The
+   QWORD Address Space Descriptor can describe memory, I/O, and bus number ranges for dynamic
+   or fixed resources. The configuration of a PCI root bridge is described with one or more QWORD
+   Address Space Descriptors followed by an End Tag.
+
+   @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[out]  Resources   A pointer to the ACPI 2.0 resource descriptors that describe the
+   current configuration of this PCI root bridge. The storage for the
+   ACPI 2.0 resource descriptors is allocated by this function. The
+   caller must treat the return buffer as read-only data, and the buffer
+   must not be freed by the caller.
+
+   @retval  EFI_SUCCESS     The current configuration of this PCI root bridge was returned in Resources.
+   @retval  EFI_UNSUPPORTED The current configuration of this PCI root bridge could not be retrieved.
+   @retval  EFI_INVALID_PARAMETER Invalid pointer of EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoConfiguration (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  OUT    VOID                             **Resources
+  );
+
+#endif /* _PCI_ROOT_BRIDGE_IO_H_ */
diff --git a/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
new file mode 100755
index 000000000000..e534bf1e44e8
--- /dev/null
+++ b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
@@ -0,0 +1,1414 @@
+/** @file
+
+  Copyright (c) 2020, Ampere Computing LLC. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiLib.h>
+#include <Library/IoLib.h>
+#include <Library/PciLib.h>
+#include <Library/PcdLib.h>
+#include <Library/PrintLib.h>
+#include <Library/TimerLib.h>
+#include <Library/DebugLib.h>
+#include <Library/ArmLib.h>
+#include <Library/PciHostBridgeLib.h>
+#include <IndustryStandard/Pci22.h>
+#include <Guid/EventGroup.h>
+#include <Library/AcpiHelperLib.h>
+#include <Library/PciHostBridgeElink.h>
+#include "PciHostBridge.h"
+#include "PciRootBridgeIo.h"
+
+EFI_HANDLE mDriverImageHandle;
+
+PCI_HOST_BRIDGE_INSTANCE mPciHostBridgeInstanceTemplate = {
+  PCI_HOST_BRIDGE_SIGNATURE,  // Signature
+  NULL,                       // HostBridgeHandle
+  0,                          // RootBridgeNumber
+  {NULL, NULL},               // Head
+  FALSE,                      // ResourceSubiteed
+  TRUE,                       // CanRestarted
+  {
+    NotifyPhase,
+    GetNextRootBridge,
+    GetAttributes,
+    StartBusEnumeration,
+    SetBusNumbers,
+    SubmitResources,
+    GetProposedResources,
+    PreprocessController
+  }
+};
+
+EFI_PCI_ROOT_BRIDGE_DEVICE_PATH mPciDevicePathTemplate =
+{
+  {
+    {
+    ACPI_DEVICE_PATH,
+    ACPI_DP,
+    {
+      (UINT8) (sizeof (ACPI_HID_DEVICE_PATH)),
+      (UINT8) ((sizeof (ACPI_HID_DEVICE_PATH)) >> 8)
+    }
+    },
+    EISA_PNP_ID (0x0A08),
+    0
+  },
+
+  {
+    END_DEVICE_PATH_TYPE,
+    END_ENTIRE_DEVICE_PATH_SUBTYPE,
+    {
+    END_DEVICE_PATH_LENGTH,
+    0
+    }
+  }
+};
+
+STATIC
+EFI_PCI_ROOT_BRIDGE_DEVICE_PATH *
+EFIAPI
+GenerateRootBridgeDevicePath (
+  UINTN HostBridgeIdx,
+  UINTN RootBridgeIdx
+  )
+{
+
+  EFI_PCI_ROOT_BRIDGE_DEVICE_PATH *RootBridgeDevPath = NULL;
+
+  RootBridgeDevPath = AllocateCopyPool (
+                        sizeof (EFI_PCI_ROOT_BRIDGE_DEVICE_PATH),
+                        (VOID *) &mPciDevicePathTemplate
+                        );
+  if (RootBridgeDevPath == NULL) {
+    return NULL;
+  }
+
+  /* We don't expect to have more than 65536 root ports on the same root bridge */
+  RootBridgeDevPath->AcpiDevicePath.UID = (UINT32) ((HostBridgeIdx << 16) + RootBridgeIdx);
+
+  return RootBridgeDevPath;
+}
+
+/**
+  This function will be called when ReadyToBoot event will be signaled.
+
+  @param Event signaled event
+  @param Context calling context
+
+  @retval VOID
+**/
+VOID
+EFIAPI
+PciHostBridgeReadyToBootEvent (
+  EFI_EVENT Event,
+  VOID *Context
+  )
+{
+  UINTN    Idx1, Idx2, Count = 0;
+  CHAR8    NodePath[MAX_ACPI_NODE_PATH];
+
+  for (Idx1 = 0; Idx1 < PCI_GET_NUMBER_HOSTBRIDGE (); Idx1++) {
+    for (Idx2 = 0; Idx2 < PCI_GET_NUMBER_ROOTBRIDGE (Idx1); Idx2++) {
+      AsciiSPrint (NodePath, sizeof (NodePath), "\\_SB.PCI%X._STA", Count);
+      if (PCI_CHECK_ROOT_BRIDGE_DISABLED (Idx1, Idx2)) {
+        AcpiDSDTSetNodeStatusValue (NodePath, 0x0);
+      } else {
+        AcpiDSDTSetNodeStatusValue (NodePath, 0xf);
+      }
+      Count++;
+    }
+  }
+}
+
+/**
+   Construct the Pci Root Bridge Io protocol
+
+   @param Protocol         Point to protocol instance
+   @param HostBridgeHandle Handle of host bridge
+   @param Attri            Attribute of host bridge
+   @param ResAppeture      ResourceAppeture for host bridge
+
+   @retval EFI_SUCCESS Success to initialize the Pci Root Bridge.
+
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+RootBridgeConstructor (
+  IN PCI_ROOT_BRIDGE_INSTANCE           *RootBridgeInstance,
+  IN EFI_HANDLE                         HostBridgeHandle,
+  IN UINT64                             Attri,
+  IN UINT32                             Seg
+  )
+{
+  MRES_TYPE                         Index;
+
+  //
+  // The host to pci bridge, the host memory and io addresses are
+  // integrated as PCIe controller subsystem resource. We move forward to mark
+  // resource as ResAllocated.
+  //
+  for (Index = rtBus; Index < rtMaxRes; Index++) {
+    RootBridgeInstance->ResAllocNode[Index].Type      = Index;
+    RootBridgeInstance->ResAllocNode[Index].Base      = 0;
+    RootBridgeInstance->ResAllocNode[Index].Length    = 0;
+    RootBridgeInstance->ResAllocNode[Index].Status    = ResNone;
+  }
+
+  RootBridgeInstance->RootBridgeAttrib                 = Attri;
+  RootBridgeInstance->RootBridge.Supports              = EFI_PCI_ATTRIBUTE_DUAL_ADDRESS_CYCLE;
+  // Support Extended (4096-byte) Configuration Space
+  RootBridgeInstance->RootBridge.NoExtendedConfigSpace = FALSE;
+  RootBridgeInstance->RootBridge.Attributes            = RootBridgeInstance->RootBridge.Supports;
+
+  RootBridgeInstance->RbIo.ParentHandle   = HostBridgeHandle;
+
+  RootBridgeInstance->RbIo.PollMem        = RootBridgeIoPollMem;
+  RootBridgeInstance->RbIo.PollIo         = RootBridgeIoPollIo;
+
+  RootBridgeInstance->RbIo.Mem.Read       = RootBridgeIoMemRead;
+  RootBridgeInstance->RbIo.Mem.Write      = RootBridgeIoMemWrite;
+
+  RootBridgeInstance->RbIo.Io.Read        = RootBridgeIoIoRead;
+  RootBridgeInstance->RbIo.Io.Write       = RootBridgeIoIoWrite;
+
+  RootBridgeInstance->RbIo.CopyMem        = RootBridgeIoCopyMem;
+
+  RootBridgeInstance->RbIo.Pci.Read       = RootBridgeIoPciRead;
+  RootBridgeInstance->RbIo.Pci.Write      = RootBridgeIoPciWrite;
+
+  RootBridgeInstance->RbIo.Map            = RootBridgeIoMap;
+  RootBridgeInstance->RbIo.Unmap          = RootBridgeIoUnmap;
+
+  RootBridgeInstance->RbIo.AllocateBuffer = RootBridgeIoAllocateBuffer;
+  RootBridgeInstance->RbIo.FreeBuffer     = RootBridgeIoFreeBuffer;
+
+  RootBridgeInstance->RbIo.Flush          = RootBridgeIoFlush;
+
+  RootBridgeInstance->RbIo.GetAttributes  = RootBridgeIoGetAttributes;
+  RootBridgeInstance->RbIo.SetAttributes  = RootBridgeIoSetAttributes;
+
+  RootBridgeInstance->RbIo.Configuration  = RootBridgeIoConfiguration;
+
+  RootBridgeInstance->RbIo.SegmentNumber  = Seg;
+
+  return EFI_SUCCESS;
+}
+
+/**
+   Entry point of this driver
+
+   @param ImageHandle     Handle of driver image
+   @param SystemTable     Point to EFI_SYSTEM_TABLE
+
+   @retval EFI_OUT_OF_RESOURCES  Can not allocate memory resource
+   @retval EFI_DEVICE_ERROR      Can not install the protocol instance
+   @retval EFI_SUCCESS           Success to initialize the Pci host bridge.
+**/
+EFI_STATUS
+EFIAPI
+InitializePciHostBridge (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  STATIC EFI_GUID                 guidReadyToBoot = EFI_EVENT_GROUP_READY_TO_BOOT;
+  EFI_EVENT                       EvtReadyToBoot;
+  EFI_STATUS                      Status;
+  UINTN                           Idx1;
+  UINTN                           Idx2;
+  UINTN                           Count = 0;
+  PCI_HOST_BRIDGE_INSTANCE        *HostBridgeInstance = NULL;
+  PCI_ROOT_BRIDGE_INSTANCE        *RootBridgeInstance = NULL;
+  UINTN                           NumberRootPortInstalled = FALSE;
+  LIST_ENTRY                      *List;
+  UINTN                           SegmentNumber;
+
+  if (( PCI_CHECK_ROOT_BRIDGE_DISABLED == NULL)
+        || (PCI_CORE_SETUP == NULL)
+        || (PCI_CORE_END == NULL)
+        || (PCI_CORE_SETUP_HOST_BRIDGE == NULL)
+        || (PCI_CORE_SETUP_ROOT_BRIDGE == NULL)
+        || (PCI_CORE_IO_PCI_RW == NULL)
+        || (PCI_GET_NUMBER_HOSTBRIDGE == NULL)
+        || (PCI_GET_NUMBER_ROOTBRIDGE == NULL)
+        || (PCI_GET_ROOTBRIDGE_ATTR == NULL ))
+  {
+    PCIE_ERR ("PciHostBridge: Invalid Parameters\n");
+    return EFI_INVALID_PARAMETER;
+  }
+
+  PCIE_DEBUG ("%a: START\n", __FUNCTION__);
+
+  mDriverImageHandle = ImageHandle;
+
+  // Inform Pcie Core BSP Driver to start setup phase
+  Status = PCI_CORE_SETUP (ImageHandle, SystemTable);
+  if (EFI_ERROR (Status)) {
+    PCIE_ERR ("  PCIe Core Setup failed!\n");
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  //
+  // Create Host Bridge Device Handle
+  //
+  for (Idx1 = 0; Idx1 < PCI_GET_NUMBER_HOSTBRIDGE (); Idx1++) {
+    HostBridgeInstance = AllocateCopyPool (
+                           sizeof (PCI_HOST_BRIDGE_INSTANCE),
+                           (VOID *) &mPciHostBridgeInstanceTemplate
+                           );
+    if (HostBridgeInstance == NULL) {
+      PCIE_ERR ("  HB%d allocation failed!\n", Idx1);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    Status = PCI_CORE_SETUP_HOST_BRIDGE (Idx1);
+    if (EFI_ERROR (Status)) {
+      FreePool (HostBridgeInstance);
+      PCIE_ERR ("  HB%d setup failed!\n", Idx1);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    HostBridgeInstance->RootBridgeNumber = PCI_GET_NUMBER_ROOTBRIDGE (Idx1);
+
+    InitializeListHead (&HostBridgeInstance->Head);
+
+    Status = gBS->InstallMultipleProtocolInterfaces (
+                    &HostBridgeInstance->HostBridgeHandle,
+                    &gEfiPciHostBridgeResourceAllocationProtocolGuid,
+                    &HostBridgeInstance->ResAlloc,
+                    NULL
+                    );
+    if (EFI_ERROR (Status)) {
+      FreePool (HostBridgeInstance);
+      PCIE_ERR ("  HB%d instance installation failed\n", Idx1);
+      return EFI_DEVICE_ERROR;
+    }
+
+    NumberRootPortInstalled = 0;
+
+    //
+    // Create Root Bridge Device Handle in this Host Bridge
+    //
+    for (Idx2 = 0; Idx2 < HostBridgeInstance->RootBridgeNumber; Idx2++, Count++) {
+      RootBridgeInstance = AllocateZeroPool (sizeof (PCI_ROOT_BRIDGE_INSTANCE));
+      if (RootBridgeInstance == NULL) {
+        gBS->UninstallMultipleProtocolInterfaces (
+               HostBridgeInstance->HostBridgeHandle,
+               &gEfiPciHostBridgeResourceAllocationProtocolGuid,
+               &HostBridgeInstance->ResAlloc,
+               NULL
+               );
+        PCIE_ERR ("    HB%d-RB%d allocation failed!\n", Idx1, Idx2);
+        return EFI_OUT_OF_RESOURCES;
+      }
+
+      // Initialize Hardware
+      Status = PCI_CORE_SETUP_ROOT_BRIDGE (Idx1, Idx2, (VOID *) &RootBridgeInstance->RootBridge);
+      if (EFI_ERROR (Status)) {
+        FreePool (RootBridgeInstance);
+        PCIE_ERR ("    HB%d-RB%d setup failed!\n", Idx1, Idx2);
+        continue;
+      }
+
+      NumberRootPortInstalled++;
+
+      RootBridgeInstance->ConfigBuffer = AllocateZeroPool (
+                                           rtMaxRes * sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR)
+                                           + sizeof (EFI_ACPI_END_TAG_DESCRIPTOR)
+                                           );
+      if (RootBridgeInstance->ConfigBuffer == NULL) {
+        gBS->UninstallMultipleProtocolInterfaces (
+               HostBridgeInstance->HostBridgeHandle,
+               &gEfiPciHostBridgeResourceAllocationProtocolGuid,
+               &HostBridgeInstance->ResAlloc,
+               NULL
+               );
+        FreePool (RootBridgeInstance);
+        PCIE_ERR ("    HB%d-RB%d Descriptor allocation failed!\n", Idx1, Idx2);
+        return EFI_OUT_OF_RESOURCES;
+      }
+
+      RootBridgeInstance->Signature = PCI_ROOT_BRIDGE_SIGNATURE;
+      RootBridgeInstance->RootBridge.DevicePath =
+        (EFI_DEVICE_PATH_PROTOCOL *) GenerateRootBridgeDevicePath (Idx1, Idx2);
+
+      SegmentNumber = Count;
+      if (PCI_GET_ROOTBRIDGE_SEGMENTNUMBER) {
+        SegmentNumber = PCI_GET_ROOTBRIDGE_SEGMENTNUMBER (Idx1, Idx2);
+      }
+
+      RootBridgeConstructor (
+        RootBridgeInstance,
+        HostBridgeInstance->HostBridgeHandle,
+        PCI_GET_ROOTBRIDGE_ATTR (Idx1),
+        SegmentNumber
+        );
+
+      Status = gBS->InstallMultipleProtocolInterfaces (
+                      &RootBridgeInstance->RootBridgeHandle,
+                      &gEfiDevicePathProtocolGuid,
+                      RootBridgeInstance->RootBridge.DevicePath,
+                      &gEfiPciRootBridgeIoProtocolGuid,
+                      &RootBridgeInstance->RbIo,
+                      NULL
+                      );
+      if (EFI_ERROR (Status)) {
+        // Uninstall all root ports of this bridge
+        List = HostBridgeInstance->Head.ForwardLink;
+        while (List != &HostBridgeInstance->Head) {
+          RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+          gBS->UninstallMultipleProtocolInterfaces (
+                 RootBridgeInstance->RootBridgeHandle,
+                 &gEfiDevicePathProtocolGuid,
+                 RootBridgeInstance->RootBridge.DevicePath,
+                 &gEfiPciRootBridgeIoProtocolGuid,
+                 &RootBridgeInstance->RbIo,
+                 NULL
+                 );
+          FreePool (RootBridgeInstance->ConfigBuffer);
+          FreePool (RootBridgeInstance);
+          List = List->ForwardLink;
+        }
+
+        gBS->UninstallMultipleProtocolInterfaces (
+               HostBridgeInstance->HostBridgeHandle,
+               &gEfiPciHostBridgeResourceAllocationProtocolGuid,
+               &HostBridgeInstance->ResAlloc,
+               NULL
+               );
+        FreePool (HostBridgeInstance);
+        PCIE_ERR ("    HB%d-RB%d instance installation failed\n", Idx1, Idx2);
+        return EFI_DEVICE_ERROR;
+      }
+
+      InsertTailList (&HostBridgeInstance->Head, &RootBridgeInstance->Link);
+    }
+
+    if (NumberRootPortInstalled == 0) {
+      PCIE_WARN ("  No Root Port! Uninstalling HB%d\n", Idx1);
+      gBS->UninstallMultipleProtocolInterfaces (
+             HostBridgeInstance->HostBridgeHandle,
+             &gEfiPciHostBridgeResourceAllocationProtocolGuid,
+             &HostBridgeInstance->ResAlloc,
+             NULL
+             );
+      FreePool (HostBridgeInstance);
+    }
+  }
+
+  // Inform BSP Pcie Driver to end setup phase
+  PCI_CORE_END ();
+
+  /* Event for ACPI Menu configuration */
+  Status = gBS->CreateEventEx (
+                  EVT_NOTIFY_SIGNAL,                 // Type,
+                  TPL_NOTIFY,                        // NotifyTpl
+                  PciHostBridgeReadyToBootEvent,     // NotifyFunction
+                  NULL,                              // NotifyContext
+                  &guidReadyToBoot,                  // EventGroup
+                  &EvtReadyToBoot                    // Event
+                  );
+
+  PCIE_DEBUG ("%a: END\n", __FUNCTION__);
+
+  return Status;
+}
+
+/**
+   These are the notifications from the PCI bus driver that it is about to enter a certain
+   phase of the PCI enumeration process.
+
+   This member function can be used to notify the host bridge driver to perform specific actions,
+   including any chipset-specific initialization, so that the chipset is ready to enter the next phase.
+   Eight notification points are defined at this time. See belows:
+   EfiPciHostBridgeBeginEnumeration       Resets the host bridge PCI apertures and internal data
+                                          structures. The PCI enumerator should issue this notification
+                                          before starting a fresh enumeration process. Enumeration cannot
+                                          be restarted after sending any other notification such as
+                                          EfiPciHostBridgeBeginBusAllocation.
+   EfiPciHostBridgeBeginBusAllocation     The bus allocation phase is about to begin. No specific action is
+                                          required here. This notification can be used to perform any
+                                          chipset-specific programming.
+   EfiPciHostBridgeEndBusAllocation       The bus allocation and bus programming phase is complete. No
+                                          specific action is required here. This notification can be used to
+                                          perform any chipset-specific programming.
+   EfiPciHostBridgeBeginResourceAllocation
+                                          The resource allocation phase is about to begin. No specific
+                                          action is required here. This notification can be used to perform
+                                          any chipset-specific programming.
+   EfiPciHostBridgeAllocateResources      Allocates resources per previously submitted requests for all the PCI
+                                          root bridges. These resource settings are returned on the next call to
+                                          GetProposedResources(). Before calling NotifyPhase() with a Phase of
+                                          EfiPciHostBridgeAllocateResource, the PCI bus enumerator is responsible
+                                          for gathering I/O and memory requests for
+                                          all the PCI root bridges and submitting these requests using
+                                          SubmitResources(). This function pads the resource amount
+                                          to suit the root bridge hardware, takes care of dependencies between
+                                          the PCI root bridges, and calls the Global Coherency Domain (GCD)
+                                          with the allocation request. In the case of padding, the allocated range
+                                          could be bigger than what was requested.
+   EfiPciHostBridgeSetResources           Programs the host bridge hardware to decode previously allocated
+                                          resources (proposed resources) for all the PCI root bridges. After the
+                                          hardware is programmed, reassigning resources will not be supported.
+                                          The bus settings are not affected.
+   EfiPciHostBridgeFreeResources          Deallocates resources that were previously allocated for all the PCI
+                                          root bridges and resets the I/O and memory apertures to their initial
+                                          state. The bus settings are not affected. If the request to allocate
+                                          resources fails, the PCI enumerator can use this notification to
+                                          deallocate previous resources, adjust the requests, and retry
+                                          allocation.
+   EfiPciHostBridgeEndResourceAllocation  The resource allocation phase is completed. No specific action is
+                                          required here. This notification can be used to perform any chipsetspecific
+                                          programming.
+
+   @param[in] This                The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in] Phase               The phase during enumeration
+
+   @retval EFI_NOT_READY          This phase cannot be entered at this time. For example, this error
+                                  is valid for a Phase of EfiPciHostBridgeAllocateResources if
+                                  SubmitResources() has not been called for one or more
+                                  PCI root bridges before this call
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error. This error is valid
+                                  for a Phase of EfiPciHostBridgeSetResources.
+   @retval EFI_INVALID_PARAMETER  Invalid phase parameter
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+                                  This error is valid for a Phase of EfiPciHostBridgeAllocateResources if the
+                                  previously submitted resource requests cannot be fulfilled or
+                                  were only partially fulfilled.
+   @retval EFI_SUCCESS            The notification was accepted without any errors.
+
+**/
+EFI_STATUS
+EFIAPI
+NotifyPhase (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PHASE    Phase
+  )
+{
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+  MRES_TYPE                             Index;
+  PCI_RES_NODE                          *ResNode;
+  LIST_ENTRY                            *List;
+  EFI_PHYSICAL_ADDRESS                  AddrBase;
+  EFI_PHYSICAL_ADDRESS                  AddrLimit;
+  UINT64                                AddrLen;
+  UINTN                                 BitsOfAlignment;
+  EFI_STATUS                            Status;
+  EFI_STATUS                            ReturnStatus;
+  EFI_PCI_ROOT_BRIDGE_DEVICE_PATH       *DevPath;
+  UINTN                                 HostBridgeIdx, RootBridgeIdx;
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  ReturnStatus = EFI_SUCCESS;
+
+  switch (Phase) {
+
+  case EfiPciHostBridgeBeginEnumeration:
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (BeginEnumeration)\n");
+
+    if (!HostBridgeInstance->CanRestarted) {
+      return EFI_NOT_READY;
+    }
+
+    //
+    // Reset each Root Bridge
+    //
+    List = HostBridgeInstance->Head.ForwardLink;
+    while (List != &HostBridgeInstance->Head) {
+      RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+      for (Index = rtBus; Index < rtMaxRes; Index++) {
+        ResNode = &(RootBridgeInstance->ResAllocNode[Index]);
+
+        ResNode->Type      = Index;
+        ResNode->Base      = 0;
+        ResNode->Length    = 0;
+        ResNode->Status    = ResNone;
+      }
+
+      List = List->ForwardLink;
+    }
+
+    HostBridgeInstance->ResourceSubmited = FALSE;
+    HostBridgeInstance->CanRestarted     = TRUE;
+    break;
+
+  case EfiPciHostBridgeEndEnumeration:
+    //
+    // The Host Bridge Enumeration is completed. No specific action is required here.
+    // This notification can be used to perform any chipset specific programming.
+    //
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (EndEnumeration)\n");
+    break;
+
+  case EfiPciHostBridgeBeginBusAllocation:
+    // No specific action is required here, can perform any chipset specific programing
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (BeginBusAllocation)\n");
+    HostBridgeInstance->CanRestarted = FALSE;
+    break;
+
+  case EfiPciHostBridgeEndBusAllocation:
+    // No specific action is required here, can perform any chipset specific programing
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (EndBusAllocation)\n");
+    break;
+
+  case EfiPciHostBridgeBeginResourceAllocation:
+    // No specific action is required here, can perform any chipset specific programing
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (BeginResourceAllocation)\n");
+    break;
+
+  case EfiPciHostBridgeAllocateResources:
+
+    // Make sure the resource for all root bridges has been submitted.
+    if (!HostBridgeInstance->ResourceSubmited) {
+      return EFI_NOT_READY;
+    }
+
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (AllocateResources)\n");
+
+    //
+    // Take care of the resource dependencies between the root bridges
+    //
+    List = HostBridgeInstance->Head.ForwardLink;
+    while (List != &HostBridgeInstance->Head) {
+
+      RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+      for (Index = rtIo16; Index < rtMaxRes; Index++) {
+        ResNode = &(RootBridgeInstance->ResAllocNode[Index]);
+
+        if (ResNode->Status == ResNone) {
+          continue;
+        }
+
+        switch (Index) {
+        case rtIo16:
+        case rtIo32:
+          AddrBase = RootBridgeInstance->RootBridge.Io.Base;
+          AddrLimit = RootBridgeInstance->RootBridge.Io.Limit;
+          break;
+
+        case rtMmio32:
+          AddrBase = RootBridgeInstance->RootBridge.Mem.Base;
+          AddrLimit = RootBridgeInstance->RootBridge.Mem.Limit;
+          break;
+
+        case rtMmio32p:
+          AddrBase = RootBridgeInstance->RootBridge.PMem.Base;
+          AddrLimit = RootBridgeInstance->RootBridge.PMem.Limit;
+          break;
+
+        case rtMmio64:
+          AddrBase = RootBridgeInstance->RootBridge.MemAbove4G.Base;
+          AddrLimit = RootBridgeInstance->RootBridge.MemAbove4G.Limit;
+          break;
+
+        case rtMmio64p:
+          AddrBase = RootBridgeInstance->RootBridge.PMemAbove4G.Base;
+          AddrLimit = RootBridgeInstance->RootBridge.PMemAbove4G.Limit;
+          break;
+
+        default:
+          ASSERT (FALSE);
+          break;
+        }; //end switch (Index)
+
+        AddrLen = ResNode->Length;
+
+        if ((AddrBase + AddrLen - 1) > AddrLimit) {
+          ReturnStatus = EFI_OUT_OF_RESOURCES;
+          ResNode->Length = 0;
+        } else {
+          // Get the number of '1' in Alignment.
+          BitsOfAlignment = (UINTN) (HighBitSet64 (ResNode->Alignment) + 1);
+
+          Status = gDS->AllocateMemorySpace (
+                          EfiGcdAllocateAddress,
+                          EfiGcdMemoryTypeMemoryMappedIo,
+                          BitsOfAlignment,
+                          AddrLen,
+                          &AddrBase,
+                          mDriverImageHandle,
+                          NULL
+                          );
+
+          if (!EFI_ERROR (Status)) {
+            ResNode->Base   = (UINTN) AddrBase;
+            ResNode->Status = ResAllocated;
+          } else {
+            ReturnStatus = EFI_OUT_OF_RESOURCES;
+            ResNode->Length = 0;
+          }
+        }
+      } // end for
+      List = List->ForwardLink;
+    } // end while
+
+    break;
+
+  case EfiPciHostBridgeSetResources:
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (SetResources)\n");
+    break;
+
+  case EfiPciHostBridgeFreeResources:
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (FreeResources)\n");
+
+    List = HostBridgeInstance->Head.ForwardLink;
+
+    while (List != &HostBridgeInstance->Head) {
+      RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+      for (Index = rtIo16; Index < rtMaxRes; Index++) {
+        ResNode = &(RootBridgeInstance->ResAllocNode[Index]);
+
+        if (ResNode->Status == ResAllocated) {
+          AddrLen = ResNode->Length;
+          AddrBase = ResNode->Base;
+
+          switch (Index) {
+          case rtIo16:
+          case rtIo32:
+          case rtMmio32:
+          case rtMmio32p:
+          case rtMmio64:
+          case rtMmio64p:
+            Status = gDS->FreeMemorySpace (AddrBase, AddrLen);
+            if (EFI_ERROR (Status)) {
+              ReturnStatus = Status;
+            }
+            break;
+
+          default:
+            ASSERT (FALSE);
+            break;
+          }; //end switch (Index)
+
+          ResNode->Type      = Index;
+          ResNode->Base      = 0;
+          ResNode->Length    = 0;
+          ResNode->Status    = ResNone;
+        }
+      }
+
+      List = List->ForwardLink;
+    }
+
+    HostBridgeInstance->ResourceSubmited = FALSE;
+    HostBridgeInstance->CanRestarted     = TRUE;
+    break;
+
+  case EfiPciHostBridgeEndResourceAllocation:
+    //
+    // The resource allocation phase is completed.  No specific action is required
+    // here. This notification can be used to perform any chipset specific programming.
+    //
+    PCIE_DEBUG ("PciHostBridge: NotifyPhase (EndResourceAllocation)\n");
+    HostBridgeInstance->CanRestarted = FALSE;
+    break;
+
+  default:
+    return EFI_INVALID_PARAMETER;
+  }
+
+  // Notify BSP Driver the phase we are being
+  List = HostBridgeInstance->Head.ForwardLink;
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+    // Retrieve the HostBridgeIdx and RootBridgeIdx from UID
+    // UID = (UINT32)((HostBridgeIdx << 16) + RootBridgeIdx);
+    DevPath = (EFI_PCI_ROOT_BRIDGE_DEVICE_PATH*) RootBridgeInstance->RootBridge.DevicePath;
+    HostBridgeIdx = DevPath->AcpiDevicePath.UID / (1<<16);
+    RootBridgeIdx = DevPath->AcpiDevicePath.UID % (1<<16);
+
+    // Notify BSP Driver
+    if (PCI_CORE_HOST_BRIDGE_NOTIFY_PHASE != NULL) {
+      PCI_CORE_HOST_BRIDGE_NOTIFY_PHASE (HostBridgeIdx, RootBridgeIdx, Phase);
+    }
+
+    List = List->ForwardLink;
+  }
+
+  return ReturnStatus;
+}
+
+/**
+   Return the device handle of the next PCI root bridge that is associated with this Host Bridge.
+
+   This function is called multiple times to retrieve the device handles of all the PCI root bridges that
+   are associated with this PCI host bridge. Each PCI host bridge is associated with one or more PCI
+   root bridges. On each call, the handle that was returned by the previous call is passed into the
+   interface, and on output the interface returns the device handle of the next PCI root bridge. The
+   caller can use the handle to obtain the instance of the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+   for that root bridge. When there are no more PCI root bridges to report, the interface returns
+   EFI_NOT_FOUND. A PCI enumerator must enumerate the PCI root bridges in the order that they
+   are returned by this function.
+   For D945 implementation, there is only one root bridge in PCI host bridge.
+
+   @param[in]       This              The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in, out]  RootBridgeHandle  Returns the device handle of the next PCI root bridge.
+
+   @retval EFI_SUCCESS            If parameter RootBridgeHandle = NULL, then return the first Rootbridge handle of the
+                                  specific Host bridge and return EFI_SUCCESS.
+   @retval EFI_NOT_FOUND          Can not find the any more root bridge in specific host bridge.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not an EFI_HANDLE that was
+                                  returned on a previous call to GetNextRootBridge().
+**/
+EFI_STATUS
+EFIAPI
+GetNextRootBridge (
+  IN       EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN OUT   EFI_HANDLE                                       *RootBridgeHandle
+  )
+{
+  BOOLEAN                               NoRootBridge;
+  LIST_ENTRY                            *List;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+
+  NoRootBridge = TRUE;
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  while (List != &HostBridgeInstance->Head) {
+    NoRootBridge = FALSE;
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+    if (*RootBridgeHandle == NULL) {
+      //
+      // Return the first Root Bridge Handle of the Host Bridge
+      //
+      *RootBridgeHandle = RootBridgeInstance->RootBridgeHandle;
+
+      return EFI_SUCCESS;
+    } else {
+      if (*RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+        //
+        // Get next if have
+        //
+        List = List->ForwardLink;
+
+        if (List != &HostBridgeInstance->Head) {
+          RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+          *RootBridgeHandle = RootBridgeInstance->RootBridgeHandle;
+
+          return EFI_SUCCESS;
+        }
+
+        return EFI_NOT_FOUND;
+      }
+    }
+
+    List = List->ForwardLink;
+  } //end while
+
+  return NoRootBridge ? EFI_NOT_FOUND : EFI_INVALID_PARAMETER;
+}
+
+/**
+   Returns the allocation attributes of a PCI root bridge.
+
+   The function returns the allocation attributes of a specific PCI root bridge. The attributes can vary
+   from one PCI root bridge to another. These attributes are different from the decode-related
+   attributes that are returned by the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.GetAttributes() member function. The
+   RootBridgeHandle parameter is used to specify the instance of the PCI root bridge. The device
+   handles of all the root bridges that are associated with this host bridge must be obtained by calling
+   GetNextRootBridge(). The attributes are static in the sense that they do not change during or
+   after the enumeration process. The hardware may provide mechanisms to change the attributes on
+   the fly, but such changes must be completed before EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL is
+   installed. The permitted values of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ATTRIBUTES are defined in
+   "Related Definitions" below. The caller uses these attributes to combine multiple resource requests.
+   For example, if the flag EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM is set, the PCI bus enumerator needs to
+   include requests for the prefetchable memory in the nonprefetchable memory pool and not request any
+   prefetchable memory.
+      Attribute                                 Description
+   ------------------------------------         ----------------------------------------------------------------------
+   EFI_PCI_HOST_BRIDGE_COMBINE_MEM_PMEM         If this bit is set, then the PCI root bridge does not support separate
+                                                windows for nonprefetchable and prefetchable memory. A PCI bus
+                                                driver needs to include requests for prefetchable memory in the
+                                                nonprefetchable memory pool.
+
+   EFI_PCI_HOST_BRIDGE_MEM64_DECODE             If this bit is set, then the PCI root bridge supports 64-bit memory
+                                                windows. If this bit is not set, the PCI bus driver needs to include
+                                                requests for a 64-bit memory address in the corresponding 32-bit
+                                                memory pool.
+
+   @param[in]   This               The instance pointer of EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+   @param[in]   RootBridgeHandle   The device handle of the PCI root bridge in which the caller is interested. Type
+                                   EFI_HANDLE is defined in InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param[out]  Attributes         The pointer to attribte of root bridge, it is output parameter
+
+   @retval EFI_INVALID_PARAMETER   Attribute pointer is NULL
+   @retval EFI_INVALID_PARAMETER   RootBridgehandle is invalid.
+   @retval EFI_SUCCESS             Success to get attribute of interested root bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+GetAttributes (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT UINT64                                           *Attributes
+  )
+{
+  LIST_ENTRY                            *List;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+
+  if (Attributes == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      *Attributes = RootBridgeInstance->RootBridgeAttrib;
+
+      return EFI_SUCCESS;
+    }
+
+    List = List->ForwardLink;
+  }
+
+  //
+  // RootBridgeHandle is not an EFI_HANDLE
+  // that was returned on a previous call to GetNextRootBridge()
+  //
+  return EFI_INVALID_PARAMETER;
+}
+
+/**
+   Sets up the specified PCI root bridge for the bus enumeration process.
+
+   This member function sets up the root bridge for bus enumeration and returns the PCI bus range
+   over which the search should be performed in ACPI 2.0 resource descriptor format.
+
+   @param[in]   This              The EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ PROTOCOL instance.
+   @param[in]   RootBridgeHandle  The PCI Root Bridge to be set up.
+   @param[out]  Configuration     Pointer to the pointer to the PCI bus resource descriptor.
+
+   @retval EFI_INVALID_PARAMETER Invalid Root bridge's handle
+   @retval EFI_OUT_OF_RESOURCES  Fail to allocate ACPI resource descriptor tag.
+   @retval EFI_SUCCESS           Sucess to allocate ACPI resource descriptor.
+
+**/
+EFI_STATUS
+EFIAPI
+StartBusEnumeration (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT VOID                                             **Configuration
+  )
+{
+  LIST_ENTRY                            *List;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+  VOID                                  *Buffer;
+  UINT8                                 *Temp;
+  UINT64                                BusStart;
+  UINT64                                BusEnd;
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      //
+      // Set up the Root Bridge for Bus Enumeration
+      //
+      BusStart = RootBridgeInstance->RootBridge.Bus.Base;
+      BusEnd   = RootBridgeInstance->RootBridge.Bus.Limit;
+
+      Buffer = AllocatePool (sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) + sizeof (EFI_ACPI_END_TAG_DESCRIPTOR));
+      if (Buffer == NULL) {
+        return EFI_OUT_OF_RESOURCES;
+      }
+
+      Temp = (UINT8 *) Buffer;
+
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->Desc = ACPI_ADDRESS_SPACE_DESCRIPTOR;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->Len  = sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) - 3;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->ResType = ACPI_ADDRESS_SPACE_TYPE_BUS;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->GenFlag = 0;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->SpecificFlag = 0;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->AddrSpaceGranularity = 0;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->AddrRangeMin = BusStart;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->AddrRangeMax = BusEnd;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->AddrTranslationOffset = 0;
+      ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)Temp)->AddrLen = BusEnd - BusStart + 1;
+
+      Temp += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR);
+      ((EFI_ACPI_END_TAG_DESCRIPTOR *)Temp)->Desc = ACPI_END_TAG_DESCRIPTOR;
+      ((EFI_ACPI_END_TAG_DESCRIPTOR *)Temp)->Checksum = 0x0;
+
+      *Configuration = Buffer;
+
+      return EFI_SUCCESS;
+    }
+
+    List = List->ForwardLink;
+  }
+
+  return EFI_INVALID_PARAMETER;
+}
+
+/**
+   Programs the PCI root bridge hardware so that it decodes the specified PCI bus range.
+
+   This member function programs the specified PCI root bridge to decode the bus range that is
+   specified by the input parameter Configuration.
+   The bus range information is specified in terms of the ACPI 2.0 resource descriptor format.
+
+   @param[in] This              The EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_ PROTOCOL instance
+   @param[in] RootBridgeHandle  The PCI Root Bridge whose bus range is to be programmed
+   @param[in] Configuration     The pointer to the PCI bus resource descriptor
+
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER  Configuration is NULL.
+   @retval EFI_INVALID_PARAMETER  Configuration does not point to a valid ACPI 2.0 resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration does not include a valid ACPI 2.0 bus resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration includes valid ACPI 2.0 resource descriptors other than
+                                  bus descriptors.
+   @retval EFI_INVALID_PARAMETER  Configuration contains one or more invalid ACPI resource descriptors.
+   @retval EFI_INVALID_PARAMETER  "Address Range Minimum" is invalid for this root bridge.
+   @retval EFI_INVALID_PARAMETER  "Address Range Length" is invalid for this root bridge.
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error.
+   @retval EFI_SUCCESS            The bus range for the PCI root bridge was programmed.
+
+**/
+EFI_STATUS
+EFIAPI
+SetBusNumbers (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_HANDLE                                       RootBridgeHandle,
+  IN VOID                                             *Configuration
+  )
+{
+  LIST_ENTRY                            *List;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+  PCI_RES_NODE                          *ResNode;
+  UINT8                                 *Ptr;
+  UINTN                                 BusStart;
+  UINTN                                 BusEnd;
+  UINTN                                 BusLen;
+
+  if (Configuration == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Ptr = Configuration;
+
+  //
+  // Check the Configuration is valid
+  //
+  if (*Ptr != ACPI_ADDRESS_SPACE_DESCRIPTOR) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Ptr)->ResType != ACPI_ADDRESS_SPACE_TYPE_BUS) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Ptr += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR);
+  if (*Ptr != ACPI_END_TAG_DESCRIPTOR) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  Ptr = Configuration;
+
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      BusStart = (UINTN) ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Ptr)->AddrRangeMin;
+      BusLen = (UINTN) ((EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Ptr)->AddrLen;
+      BusEnd = BusStart + BusLen - 1;
+
+      if (BusStart > BusEnd) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      if ((BusStart < RootBridgeInstance->RootBridge.Bus.Base) ||
+          (BusEnd > RootBridgeInstance->RootBridge.Bus.Limit)) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      //
+      // Update the Bus Range
+      //
+      ResNode = &(RootBridgeInstance->ResAllocNode[rtBus]);
+      ResNode->Base   = BusStart;
+      ResNode->Length = BusLen;
+      ResNode->Status = ResAllocated;
+
+      return EFI_SUCCESS;
+    }
+
+    List = List->ForwardLink;
+  }
+
+  return EFI_INVALID_PARAMETER;
+}
+
+/**
+   Submits the I/O and memory resource requirements for the specified PCI root bridge.
+
+   This function is used to submit all the I/O and memory resources that are required by the specified
+   PCI root bridge. The input parameter Configuration is used to specify the following:
+   - The various types of resources that are required
+   - The associated lengths in terms of ACPI 2.0 resource descriptor format
+
+   @param[in] This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param[in] RootBridgeHandle  The PCI root bridge whose I/O and memory resource requirements are being submitted.
+   @param[in] Configuration     The pointer to the PCI I/O and PCI memory resource descriptor.
+
+   @retval EFI_SUCCESS            The I/O and memory resource requests for a PCI root bridge were accepted.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER  Configuration is NULL.
+   @retval EFI_INVALID_PARAMETER  Configuration does not point to a valid ACPI 2.0 resource descriptor.
+   @retval EFI_INVALID_PARAMETER  Configuration includes requests for one or more resource types that are
+                                  not supported by this PCI root bridge. This error will happen if the caller
+                                  did not combine resources according to Attributes that were returned by
+                                  GetAllocAttributes().
+   @retval EFI_INVALID_PARAMETER  Address Range Maximum" is invalid.
+   @retval EFI_INVALID_PARAMETER  "Address Range Length" is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  "Address Space Granularity" is invalid for this PCI root bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+SubmitResources (
+  IN EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN EFI_HANDLE                                       RootBridgeHandle,
+  IN VOID                                             *Configuration
+  )
+{
+  LIST_ENTRY                            *List;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance = NULL;
+  PCI_RES_NODE                          *ResNode;
+  UINT8                                 *Temp;
+  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR     *Ptr;
+  UINTN                                 Index = 0;
+  UINTN                                 AddrSpaceCnt = 0;
+  UINTN                                 i;
+
+  //
+  // Check the input parameter: Configuration
+  //
+  if (Configuration == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  //
+  // Input resource descriptor must end properly
+  //
+  Temp = (UINT8 *) Configuration;
+  AddrSpaceCnt = 0;
+  while (*Temp == ACPI_ADDRESS_SPACE_DESCRIPTOR) {
+    Temp += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR);
+    AddrSpaceCnt ++;
+  }
+  if (*Temp != ACPI_END_TAG_DESCRIPTOR) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Get the corresponding Root Bridge Instance
+  //
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      break;
+    }
+
+    List = List->ForwardLink;
+  }
+
+  if (RootBridgeHandle != RootBridgeInstance->RootBridgeHandle) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  PCIE_DEBUG ("%a: \n", __FUNCTION__);
+
+  Temp = (UINT8 *) Configuration;
+  for (i = 0; i < AddrSpaceCnt; i ++) {
+    Ptr = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Temp ;
+
+    PCIE_DEBUG ("Ptr->ResType:%d\n", Ptr->ResType);
+    PCIE_DEBUG ("Ptr->Addrlen:0x%llx\n", Ptr->AddrLen);
+    PCIE_DEBUG ("Ptr->AddrRangeMax:0x%llx\n", Ptr->AddrRangeMax);
+    PCIE_DEBUG ("Ptr->AddrRangeMin:0x%llx\n", Ptr->AddrRangeMin);
+    PCIE_DEBUG ("Ptr->SpecificFlag:0x%llx\n", Ptr->SpecificFlag);
+    PCIE_DEBUG ("Ptr->AddrSpaceGranularity:%d\n", Ptr->AddrSpaceGranularity);
+    PCIE_DEBUG ("RootBridgeInstance->RootBridgeAttrib:0x%llx\n", RootBridgeInstance->RootBridgeAttrib);
+
+    switch (Ptr->ResType) {
+    case ACPI_ADDRESS_SPACE_TYPE_MEM:
+
+      if (Ptr->AddrSpaceGranularity != 32 && Ptr->AddrSpaceGranularity != 64) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      if (Ptr->AddrSpaceGranularity == 32) {
+        if (Ptr->AddrLen >= SIZE_4GB) {
+          return EFI_INVALID_PARAMETER;
+        }
+
+        Index = (Ptr->SpecificFlag & EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE) ?
+                   rtMmio32p : rtMmio32;
+      }
+
+      if (Ptr->AddrSpaceGranularity == 64) {
+        Index = (Ptr->SpecificFlag & EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE) ?
+                   rtMmio64p : rtMmio64;
+      }
+
+      break;
+
+    case ACPI_ADDRESS_SPACE_TYPE_IO:
+      //
+      // Check address range alignment
+      //
+      if (Ptr->AddrRangeMax != (GetPowerOfTwo64 (Ptr->AddrRangeMax + 1) - 1)) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      Index = rtIo32;
+      break;
+
+    case ACPI_ADDRESS_SPACE_TYPE_BUS:
+    default:
+      ASSERT (FALSE);
+      break;
+    };
+
+    ResNode = &(RootBridgeInstance->ResAllocNode[Index]);
+    ResNode->Length  = Ptr->AddrLen;
+    ResNode->Alignment = Ptr->AddrRangeMax;
+    ResNode->Status  = ResSubmitted;
+
+    Temp += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) ;
+  }
+
+  HostBridgeInstance->ResourceSubmited = TRUE;
+  return EFI_SUCCESS;
+}
+
+/**
+   Returns the proposed resource settings for the specified PCI root bridge.
+
+   This member function returns the proposed resource settings for the specified PCI root bridge. The
+   proposed resource settings are prepared when NotifyPhase() is called with a Phase of
+   EfiPciHostBridgeAllocateResources. The output parameter Configuration
+   specifies the following:
+   - The various types of resources, excluding bus resources, that are allocated
+   - The associated lengths in terms of ACPI 2.0 resource descriptor format
+
+   @param[in]  This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param[in]  RootBridgeHandle  The PCI root bridge handle. Type EFI_HANDLE is defined in InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param[out] Configuration     The pointer to the pointer to the PCI I/O and memory resource descriptor.
+
+   @retval EFI_SUCCESS            The requested parameters were returned.
+   @retval EFI_INVALID_PARAMETER  RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_DEVICE_ERROR       Programming failed due to a hardware error.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProposedResources (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL *This,
+  IN  EFI_HANDLE                                       RootBridgeHandle,
+  OUT VOID                                             **Configuration
+  )
+{
+  LIST_ENTRY                            *List = NULL;
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance = NULL;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance = NULL;
+  UINTN                                 Index = 0;
+  VOID                                  *Buffer = NULL;
+  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR     *Descriptor = NULL;
+  EFI_ACPI_END_TAG_DESCRIPTOR           *End = NULL;
+  UINT64                                ResStatus;
+
+  Buffer = NULL;
+
+  PCIE_DEBUG ("%a: \n", __FUNCTION__);
+
+  //
+  // Get the Host Bridge Instance from the resource allocation protocol
+  //
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  //
+  // Get the corresponding Root Bridge Instance
+  //
+  while (List != &HostBridgeInstance->Head) {
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      break;
+    }
+
+    List = List->ForwardLink;
+  }
+
+  if (RootBridgeHandle != RootBridgeInstance->RootBridgeHandle) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Buffer = AllocateZeroPool (
+             (rtMaxRes - 1) * sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) +
+             sizeof (EFI_ACPI_END_TAG_DESCRIPTOR)
+             );
+  if (Buffer == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Descriptor = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Buffer;
+  for (Index = rtIo16; Index < rtMaxRes; Index++) {
+    ResStatus = RootBridgeInstance->ResAllocNode[Index].Status;
+
+    Descriptor->Desc                  = ACPI_ADDRESS_SPACE_DESCRIPTOR;
+    Descriptor->Len                   = sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) - 3;;
+    Descriptor->GenFlag               = 0;
+    Descriptor->AddrRangeMin          = RootBridgeInstance->ResAllocNode[Index].Base;
+    Descriptor->AddrLen               = RootBridgeInstance->ResAllocNode[Index].Length;
+    Descriptor->AddrRangeMax          = Descriptor->AddrRangeMin + Descriptor->AddrLen - 1;
+    Descriptor->AddrTranslationOffset = (ResStatus == ResAllocated) ? EFI_RESOURCE_SATISFIED : PCI_RESOURCE_LESS;
+
+    switch (Index) {
+    case rtIo16:
+    case rtIo32:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_IO;
+      Descriptor->SpecificFlag         = 0;
+      Descriptor->AddrSpaceGranularity = 32;
+      break;
+
+    case rtMmio32:
+    case rtMmio32p:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_MEM;
+      Descriptor->SpecificFlag         = (Index == rtMmio32) ? 0 :
+                                           EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE;
+      Descriptor->AddrSpaceGranularity = 32;
+      break;
+
+    case rtMmio64:
+    case rtMmio64p:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_MEM;
+      Descriptor->SpecificFlag         = (Index == rtMmio64) ? 0 :
+                                           EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE;
+      Descriptor->AddrSpaceGranularity = 64;
+      break;
+    };
+
+    PCIE_DEBUG ("Descriptor->ResType:%d\n", Descriptor->ResType);
+    PCIE_DEBUG ("Descriptor->Addrlen:%llx\n", Descriptor->AddrLen);
+    PCIE_DEBUG ("Descriptor->AddrRangeMax:%llx\n", Descriptor->AddrRangeMax);
+    PCIE_DEBUG ("Descriptor->AddrRangeMin:%llx\n", Descriptor->AddrRangeMin);
+    PCIE_DEBUG ("Descriptor->SpecificFlag:%llx\n", Descriptor->SpecificFlag);
+    PCIE_DEBUG ("Descriptor->AddrTranslationOffset:%d\n", Descriptor->AddrTranslationOffset);
+    PCIE_DEBUG ("Descriptor->AddrSpaceGranularity:%d\n", Descriptor->AddrSpaceGranularity);
+
+    Descriptor++;
+  }
+
+  //
+  // Terminate the entries.
+  //
+  End = (EFI_ACPI_END_TAG_DESCRIPTOR *) Descriptor;
+  End->Desc      = ACPI_END_TAG_DESCRIPTOR;
+  End->Checksum  = 0x0;
+
+  *Configuration = Buffer;
+
+  return EFI_SUCCESS;
+}
+
+/**
+   Provides the hooks from the PCI bus driver to every PCI controller (device/function) at various
+   stages of the PCI enumeration process that allow the host bridge driver to preinitialize individual
+   PCI controllers before enumeration.
+
+   This function is called during the PCI enumeration process. No specific action is expected from this
+   member function. It allows the host bridge driver to preinitialize individual PCI controllers before
+   enumeration.
+
+   @param This              Pointer to the EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL instance.
+   @param RootBridgeHandle  The associated PCI root bridge handle. Type EFI_HANDLE is defined in
+                            InstallProtocolInterface() in the UEFI 2.0 Specification.
+   @param PciAddress        The address of the PCI device on the PCI bus. This address can be passed to the
+                            EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL member functions to access the PCI
+                            configuration space of the device. See Table 12-1 in the UEFI 2.0 Specification for
+                            the definition of EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS.
+   @param Phase             The phase of the PCI device enumeration.
+
+   @retval EFI_SUCCESS              The requested parameters were returned.
+   @retval EFI_INVALID_PARAMETER    RootBridgeHandle is not a valid root bridge handle.
+   @retval EFI_INVALID_PARAMETER    Phase is not a valid phase that is defined in
+                                    EFI_PCI_CONTROLLER_RESOURCE_ALLOCATION_PHASE.
+   @retval EFI_DEVICE_ERROR         Programming failed due to a hardware error. The PCI enumerator should
+                                    not enumerate this device, including its child devices if it is a PCI-to-PCI
+                                    bridge.
+
+**/
+EFI_STATUS
+EFIAPI
+PreprocessController (
+  IN  EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL          *This,
+  IN  EFI_HANDLE                                                RootBridgeHandle,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS               PciAddress,
+  IN  EFI_PCI_CONTROLLER_RESOURCE_ALLOCATION_PHASE              Phase
+  )
+{
+  PCI_HOST_BRIDGE_INSTANCE              *HostBridgeInstance;
+  PCI_ROOT_BRIDGE_INSTANCE              *RootBridgeInstance;
+  LIST_ENTRY                            *List;
+
+  HostBridgeInstance = PCI_HOST_BRIDGE_FROM_THIS (This);
+  List = HostBridgeInstance->Head.ForwardLink;
+
+  //
+  // Enumerate the root bridges in this host bridge
+  //
+  while (List != &HostBridgeInstance->Head) {
+
+    RootBridgeInstance = ROOT_BRIDGE_FROM_LINK (List);
+    if (RootBridgeHandle == RootBridgeInstance->RootBridgeHandle) {
+      break;
+    }
+    List = List->ForwardLink;
+  }
+
+  if (List == &HostBridgeInstance->Head) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if ((UINT32) Phase > EfiPciBeforeResourceCollection) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  return EFI_SUCCESS;
+}
diff --git a/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
new file mode 100755
index 000000000000..1d337b1216b4
--- /dev/null
+++ b/Silicon/Ampere/AmpereAltraPkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
@@ -0,0 +1,1558 @@
+/** @file
+
+  Copyright (c) 2020, Ampere Computing LLC. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiLib.h>
+#include <Library/IoLib.h>
+#include <Library/PciLib.h>
+#include <Library/PcdLib.h>
+#include <Library/TimerLib.h>
+#include <Library/DebugLib.h>
+#include <Library/ArmLib.h>
+#include <Library/PciHostBridgeLib.h>
+#include <Library/PciHostBridgeElink.h>
+#include <IndustryStandard/Pci22.h>
+
+#include "PciHostBridge.h"
+#include "PciRootBridgeIo.h"
+
+//
+// Memory Controller Pci Root Bridge Io Module Variables
+//
+EFI_METRONOME_ARCH_PROTOCOL *mMetronome = NULL;
+
+//
+// Lookup table for increment values based on transfer widths
+//
+UINT8 mInStride[] = {
+  1, // EfiPciWidthUint8
+  2, // EfiPciWidthUint16
+  4, // EfiPciWidthUint32
+  8, // EfiPciWidthUint64
+  0, // EfiPciWidthFifoUint8
+  0, // EfiPciWidthFifoUint16
+  0, // EfiPciWidthFifoUint32
+  0, // EfiPciWidthFifoUint64
+  1, // EfiPciWidthFillUint8
+  2, // EfiPciWidthFillUint16
+  4, // EfiPciWidthFillUint32
+  8  // EfiPciWidthFillUint64
+};
+
+//
+// Lookup table for increment values based on transfer widths
+//
+UINT8 mOutStride[] = {
+  1, // EfiPciWidthUint8
+  2, // EfiPciWidthUint16
+  4, // EfiPciWidthUint32
+  8, // EfiPciWidthUint64
+  1, // EfiPciWidthFifoUint8
+  2, // EfiPciWidthFifoUint16
+  4, // EfiPciWidthFifoUint32
+  8, // EfiPciWidthFifoUint64
+  0, // EfiPciWidthFillUint8
+  0, // EfiPciWidthFillUint16
+  0, // EfiPciWidthFillUint32
+  0  // EfiPciWidthFillUint64
+};
+
+/**
+  Check parameters for IO, MMIO, PCI read/write services of PCI Root Bridge IO.
+
+  The I/O operations are carried out exactly as requested. The caller is
+  responsible for satisfying any alignment and I/O width restrictions that a PI
+  System on a platform might require. For example on some platforms, width
+  requests of EfiCpuIoWidthUint64 do not work. Misaligned buffers, on the other
+  hand, will be handled by the driver.
+
+  @param[in] This           A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+
+  @param[in] OperationType  I/O operation type: IO/MMIO/PCI.
+
+  @param[in] Width          Signifies the width of the I/O or Memory operation.
+
+  @param[in] Address        The base address of the I/O operation.
+
+  @param[in] Count          The number of I/O operations to perform. The number
+                            of bytes moved is Width size * Count, starting at
+                            Address.
+
+  @param[in] Buffer         For read operations, the destination buffer to
+                            store the results. For write operations, the source
+                            buffer from which to write data.
+
+  @retval EFI_SUCCESS            The parameters for this request pass the
+                                 checks.
+
+  @retval EFI_INVALID_PARAMETER  Width is invalid for this PI system.
+
+  @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+
+  @retval EFI_UNSUPPORTED        The Buffer is not aligned for the given Width.
+
+  @retval EFI_UNSUPPORTED        The address range specified by Address, Width,
+                                 and Count is not valid for this PI system.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoCheckParameter (
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN OPERATION_TYPE                         OperationType,
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN UINT64                                 Address,
+  IN UINTN                                  Count,
+  IN VOID                                   *Buffer
+  )
+{
+  PCI_ROOT_BRIDGE_INSTANCE                     *RootBridgeInstance;
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS  *PciRbAddr;
+  UINT64                                       MaxCount;
+  UINT64                                       Base = 0;
+  UINT64                                       Limit = 0;
+  UINT32                                       Size;
+
+  //
+  // Check to see if Buffer is NULL
+  //
+  if (Buffer == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Check to see if Width is in the valid range
+  //
+  if ((UINT32) Width >= EfiPciWidthMaximum) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // For FIFO type, the target address won't increase during the access,
+  // so treat Count as 1
+  //
+  if (Width >= EfiPciWidthFifoUint8 && Width <= EfiPciWidthFifoUint64) {
+    Count = 1;
+  }
+
+  //
+  // Check to see if Width is in the valid range for I/O Port operations
+  //
+  Width = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH) (Width & 0x03);
+  Size  = 1 << Width;
+
+  //
+  // Config space accessing does not support 64-bit width
+  //
+  if ((OperationType == PciOperation) && (Width == EfiPciWidthUint64)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  RootBridgeInstance = ROOT_BRIDGE_FROM_THIS (This);
+
+  //
+  // Check to see if any address associated with this transfer exceeds the
+  // maximum allowed address.  The maximum address implied by the parameters
+  // passed in is Address + Size * Count.  If the following condition is met,
+  // then the transfer is not supported.
+  //
+  //    Address + Size * Count > Limit + 1
+  //
+  // Since Limit can be the maximum integer value supported by the CPU and
+  // Count can also be the maximum integer value supported by the CPU, this
+  // range check must be adjusted to avoid all oveflow conditions.
+  //
+  if (OperationType == IoOperation) {
+    if (Address + MultU64x32 (Count, Size) <= RootBridgeInstance->RootBridge.Io.Limit + 1) {
+      Base = RootBridgeInstance->RootBridge.Io.Base;
+      Limit = RootBridgeInstance->RootBridge.Io.Limit;
+    }
+  } else if (OperationType == MemOperation) {
+    if (Address + MultU64x32 (Count, Size) <= RootBridgeInstance->RootBridge.Mem.Limit + 1) {
+      Base = RootBridgeInstance->RootBridge.Mem.Base;
+      Limit = RootBridgeInstance->RootBridge.Mem.Limit;
+    } else if (Address + MultU64x32 (Count, Size) <= RootBridgeInstance->RootBridge.PMem.Limit + 1) {
+      Base = RootBridgeInstance->RootBridge.PMem.Base;
+      Limit = RootBridgeInstance->RootBridge.PMem.Limit;
+    } else if (Address + MultU64x32 (Count, Size) <= RootBridgeInstance->RootBridge.MemAbove4G.Limit + 1) {
+      Base = RootBridgeInstance->RootBridge.MemAbove4G.Base;
+      Limit = RootBridgeInstance->RootBridge.MemAbove4G.Limit;
+    } else {
+      Base = RootBridgeInstance->RootBridge.PMemAbove4G.Base;
+      Limit = RootBridgeInstance->RootBridge.PMemAbove4G.Limit;
+    }
+  } else {
+    PciRbAddr = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS*) &Address;
+    if (PciRbAddr->Bus < RootBridgeInstance->RootBridge.Bus.Base ||
+      PciRbAddr->Bus > RootBridgeInstance->RootBridge.Bus.Limit) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    if (PciRbAddr->Device > PCI_MAX_DEVICE ||
+      PciRbAddr->Function > PCI_MAX_FUNC) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    Address = (PciRbAddr->ExtendedRegister != 0) ?
+                 PciRbAddr->ExtendedRegister :
+                 PciRbAddr->Register;
+
+    Base = 0;
+    Limit = RootBridgeInstance->RootBridge.NoExtendedConfigSpace ? 0xFF : 0xFFF;
+  }
+
+  //
+  // Check to see if Address is aligned
+  // ( Address is derived from  Extended register/Register.
+  //   Now we can safely check the alignments )
+  //
+  if ((Address & (UINT64) (mInStride[Width] - 1)) != 0) {
+    return EFI_UNSUPPORTED;
+  }
+
+  if (Address < Base) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (Count == 0) {
+    if (Address > Limit) {
+      return EFI_UNSUPPORTED;
+    }
+  } else {
+    MaxCount = RShiftU64 (Limit, Width);
+    if (MaxCount < (Count - 1)) {
+      return EFI_UNSUPPORTED;
+    }
+    if (Address > LShiftU64 (MaxCount - Count + 1, Width)) {
+      return EFI_UNSUPPORTED;
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+   Internal help function for read and write memory space.
+
+   @param[in]   This          A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Write         Switch value for Read or Write.
+   @param[in]   Width         Signifies the width of the memory operations.
+   @param[in]   UserAddress   The address within the PCI configuration space for the PCI controller.
+   @param[in]   Count         The number of PCI configuration operations to perform. Bytes
+                              moved is Width size * Count, starting at Address.
+   @param[in, out] UserBuffer For read operations, the destination buffer to store the results. For
+                              write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMemRW (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     BOOLEAN                                Write,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  IN OUT VOID                                   *Buffer
+  )
+{
+  EFI_STATUS                             Status;
+  UINT8                                  InStride;
+  UINT8                                  OutStride;
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  OperationWidth;
+  UINT8                                  *Uint8Buffer;
+
+  PCIE_MMIO_DEBUG("%a: W: %d, Width: %d, Addr: 0x%lx, Count: %d\n", __FUNCTION__,
+      Write, Width, Address, Count);
+
+  Status = RootBridgeIoCheckParameter (This, MemOperation, Width, Address, Count, Buffer);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  InStride = mInStride[Width];
+  OutStride = mOutStride[Width];
+  OperationWidth = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH) (Width & 0x03);
+
+  for (Uint8Buffer = Buffer; Count > 0; Address += InStride, Uint8Buffer += OutStride, Count--) {
+    if (Write) {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        MmioWrite8 ((UINTN) Address, *Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint16:
+        MmioWrite16 ((UINTN) Address, *((UINT16 *) Uint8Buffer));
+        break;
+
+      case EfiPciWidthUint32:
+        MmioWrite32 ((UINTN) Address, *((UINT32 *) Uint8Buffer));
+        break;
+
+      case EfiPciWidthUint64:
+        MmioWrite64 ((UINTN) Address, *((UINT64 *) Uint8Buffer));
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    } else {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        *Uint8Buffer = MmioRead8 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint16:
+        *((UINT16 *) Uint8Buffer) = MmioRead16 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint32:
+        *((UINT32 *) Uint8Buffer) = MmioRead32 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint64:
+        *((UINT64 *) Uint8Buffer) = MmioRead64 ((UINTN) Address);
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+   Internal help function for read and write IO space.
+
+   @param[in]   This          A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Write         Switch value for Read or Write.
+   @param[in]   Width         Signifies the width of the memory operations.
+   @param[in]   UserAddress   The address within the PCI configuration space for the PCI controller.
+   @param[in]   Count         The number of PCI configuration operations to perform. Bytes
+                              moved is Width size * Count, starting at Address.
+   @param[in, out] UserBuffer For read operations, the destination buffer to store the results. For
+                              write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoIoRW (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     BOOLEAN                                Write,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  IN OUT VOID                                   *Buffer
+  )
+{
+  EFI_STATUS                             Status;
+  UINT8                                  InStride;
+  UINT8                                  OutStride;
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  OperationWidth;
+  UINT8                                  *Uint8Buffer;
+
+  PCIE_MMIO_DEBUG ("%a: W: %d, Width: %d, Addr: 0x%lx, Count: %d\n", __FUNCTION__,
+      Write, Width, Address, Count);
+
+  Status = RootBridgeIoCheckParameter (This, IoOperation, Width, Address, Count, Buffer);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  InStride = mInStride[Width];
+  OutStride = mOutStride[Width];
+  OperationWidth = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH) (Width & 0x03);
+
+  for (Uint8Buffer = Buffer; Count > 0; Address += InStride, Uint8Buffer += OutStride, Count--) {
+    if (Write) {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        MmioWrite8 ((UINTN) Address, *Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint16:
+        MmioWrite16 ((UINTN) Address, *((UINT16 *) Uint8Buffer));
+        break;
+
+      case EfiPciWidthUint32:
+        MmioWrite32 ((UINTN) Address, *((UINT32 *) Uint8Buffer));
+        break;
+
+      case EfiPciWidthUint64:
+        MmioWrite64 ((UINTN) Address, *((UINT64 *) Uint8Buffer));
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    } else {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        *Uint8Buffer = MmioRead8 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint16:
+        *((UINT16 *) Uint8Buffer) = MmioRead16 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint32:
+        *((UINT32 *) Uint8Buffer) = MmioRead32 ((UINTN) Address);
+        break;
+
+      case EfiPciWidthUint64:
+        *((UINT64 *) Uint8Buffer) = MmioRead64 ((UINTN) Address);
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+   Internal help function for read and write PCI configuration space.
+
+   @param[in]   This          A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+   @param[in]   Write         Switch value for Read or Write.
+   @param[in]   Width         Signifies the width of the memory operations.
+   @param[in]   UserAddress   The address within the PCI configuration space for the PCI controller.
+   @param[in]   Count         The number of PCI configuration operations to perform. Bytes
+                              moved is Width size * Count, starting at Address.
+   @param[in, out] UserBuffer For read operations, the destination buffer to store the results. For
+                              write operations, the source buffer to write data from.
+
+   @retval EFI_SUCCESS            The data was read from or written to the PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+   @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
+
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPciRW (
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN BOOLEAN                                Write,
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN UINT64                                 Address,
+  IN UINTN                                  Count,
+  IN OUT VOID                               *Buffer
+  )
+{
+  EFI_STATUS                                   Status;
+  UINT8                                        InStride;
+  UINT8                                        OutStride;
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH        OperationWidth;
+  UINT8                                        *Uint8Buffer;
+  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS  *PciRbAddr;
+  UINTN                                        PcieRegAddr;
+  PCI_ROOT_BRIDGE_INSTANCE                     *RootBridgeInstance;
+
+  OperationWidth = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH) (Width & 0x03);
+  PciRbAddr = (EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_PCI_ADDRESS*) &Address;
+
+  Status = RootBridgeIoCheckParameter (This, PciOperation, Width, Address, Count, Buffer);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  RootBridgeInstance = ROOT_BRIDGE_FROM_THIS (This);
+
+  PcieRegAddr = (UINTN) PCI_LIB_ADDRESS (
+      PciRbAddr->Bus,
+      PciRbAddr->Device,
+      PciRbAddr->Function,
+      (PciRbAddr->ExtendedRegister != 0) ? PciRbAddr->ExtendedRegister : PciRbAddr->Register
+      );
+
+  //
+  // Select loop based on the width of the transfer
+  //
+  InStride  = mInStride[Width];
+  OutStride = mOutStride[Width];
+
+  for (Uint8Buffer = Buffer; Count > 0; PcieRegAddr += InStride, Uint8Buffer += OutStride, Count--) {
+    if (Write) {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, TRUE, 1, Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint16:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, TRUE, 2, Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint32:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, TRUE, 4, Uint8Buffer);
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    } else {
+      switch (OperationWidth) {
+      case EfiPciWidthUint8:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, FALSE, 1, Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint16:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, FALSE, 2, Uint8Buffer);
+        break;
+
+      case EfiPciWidthUint32:
+        PCI_CORE_IO_PCI_RW ((VOID *) &RootBridgeInstance->RootBridge, PcieRegAddr, FALSE, 4, Uint8Buffer);
+        break;
+
+      default:
+        //
+        // The RootBridgeIoCheckParameter call above will ensure that this
+        // path is not taken.
+        //
+        ASSERT (FALSE);
+        break;
+      }
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Polls an address in memory mapped I/O space until an exit condition is met,
+  or a timeout occurs.
+
+  This function provides a standard way to poll a PCI memory location. A PCI
+  memory read operation is performed at the PCI memory address specified by
+  Address for the width specified by Width. The result of this PCI memory read
+  operation is stored in Result. This PCI memory read operation is repeated
+  until either a timeout of Delay 100 ns units has expired, or (Result & Mask)
+  is equal to Value.
+
+  @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in]   Width     Signifies the width of the memory operations.
+  @param[in]   Address   The base address of the memory operations. The caller
+                         is responsible for aligning Address if required.
+  @param[in]   Mask      Mask used for the polling criteria. Bytes above Width
+                         in Mask are ignored. The bits in the bytes below Width
+                         which are zero in Mask are ignored when polling the
+                         memory address.
+  @param[in]   Value     The comparison value used for the polling exit
+                         criteria.
+  @param[in]   Delay     The number of 100 ns units to poll. Note that timer
+                         available may be of poorer granularity.
+  @param[out]  Result    Pointer to the last value read from the memory
+                         location.
+
+  @retval EFI_SUCCESS            The last data returned from the access matched
+                                 the poll exit criteria.
+  @retval EFI_INVALID_PARAMETER  Width is invalid.
+  @retval EFI_INVALID_PARAMETER  Result is NULL.
+  @retval EFI_TIMEOUT            Delay expired before a match occurred.
+  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a
+                                 lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPollMem (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN  UINT64                                 Address,
+  IN  UINT64                                 Mask,
+  IN  UINT64                                 Value,
+  IN  UINT64                                 Delay,
+  OUT UINT64                                 *Result
+  )
+{
+  EFI_STATUS  Status;
+  UINT64      NumberOfTicks;
+  UINT32      Remainder;
+
+  if (Result == NULL || (UINT32) Width > EfiPciWidthUint64) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // No matter what, always do a single poll.
+  //
+  Status = This->Mem.Read (This, Width, Address, 1, Result);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  if ((*Result & Mask) == Value) {
+    return EFI_SUCCESS;
+  }
+
+  if (Delay == 0) {
+    return EFI_SUCCESS;
+  }
+
+  if (mMetronome == NULL) {
+    Status = gBS->LocateProtocol (
+        &gEfiMetronomeArchProtocolGuid,
+        NULL,
+        (VOID **) &mMetronome
+        );
+    if (EFI_ERROR (Status)) {
+      return EFI_OUT_OF_RESOURCES;
+    }
+  }
+
+  //
+  // Determine the proper # of metronome ticks to wait for polling the
+  // location.  The nuber of ticks is Roundup (Delay / mMetronome->TickPeriod)+1
+  // The "+1" to account for the possibility of the first tick being short
+  // because we started in the middle of a tick.
+  //
+  // BugBug: overriding mMetronome->TickPeriod with UINT32 until Metronome
+  // protocol definition is updated.
+  //
+  NumberOfTicks = DivU64x32Remainder (Delay, (UINT32) mMetronome->TickPeriod, \
+                    &Remainder);
+  if (Remainder != 0) {
+    NumberOfTicks += 1;
+  }
+  NumberOfTicks += 1;
+
+  while (NumberOfTicks != 0) {
+
+    mMetronome->WaitForTick (mMetronome, 1);
+
+    Status = This->Mem.Read (This, Width, Address, 1, Result);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+
+    if ((*Result & Mask) == Value) {
+      return EFI_SUCCESS;
+    }
+
+    NumberOfTicks -= 1;
+  }
+
+  return EFI_TIMEOUT;
+}
+
+/**
+  Reads from the I/O space of a PCI Root Bridge. Returns when either the
+  polling exit criteria is satisfied or after a defined duration.
+
+  This function provides a standard way to poll a PCI I/O location. A PCI I/O
+  read operation is performed at the PCI I/O address specified by Address for
+  the width specified by Width.
+  The result of this PCI I/O read operation is stored in Result. This PCI I/O
+  read operation is repeated until either a timeout of Delay 100 ns units has
+  expired, or (Result & Mask) is equal to Value.
+
+  @param[in] This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in] Width     Signifies the width of the I/O operations.
+  @param[in] Address   The base address of the I/O operations. The caller is
+                       responsible for aligning Address if required.
+  @param[in] Mask      Mask used for the polling criteria. Bytes above Width in
+                       Mask are ignored. The bits in the bytes below Width
+                       which are zero in Mask are ignored when polling the I/O
+                       address.
+  @param[in] Value     The comparison value used for the polling exit criteria.
+  @param[in] Delay     The number of 100 ns units to poll. Note that timer
+                       available may be of poorer granularity.
+  @param[out] Result   Pointer to the last value read from the memory location.
+
+  @retval EFI_SUCCESS            The last data returned from the access matched
+                                 the poll exit criteria.
+  @retval EFI_INVALID_PARAMETER  Width is invalid.
+  @retval EFI_INVALID_PARAMETER  Result is NULL.
+  @retval EFI_TIMEOUT            Delay expired before a match occurred.
+  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a
+                                 lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPollIo (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN  UINT64                                 Address,
+  IN  UINT64                                 Mask,
+  IN  UINT64                                 Value,
+  IN  UINT64                                 Delay,
+  OUT UINT64                                 *Result
+  )
+{
+  EFI_STATUS  Status;
+  UINT64      NumberOfTicks;
+  UINT32      Remainder;
+
+  //
+  // No matter what, always do a single poll.
+  //
+
+  if (Result == NULL || (UINT32) Width > EfiPciWidthUint64) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = This->Io.Read (This, Width, Address, 1, Result);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  if ((*Result & Mask) == Value) {
+    return EFI_SUCCESS;
+  }
+
+  if (Delay == 0) {
+    return EFI_SUCCESS;
+  }
+
+  //
+  // Determine the proper # of metronome ticks to wait for polling the
+  // location.  The number of ticks is Roundup (Delay / mMetronome->TickPeriod)+1
+  // The "+1" to account for the possibility of the first tick being short
+  // because we started in the middle of a tick.
+  //
+  NumberOfTicks = DivU64x32Remainder (Delay, (UINT32) mMetronome->TickPeriod, \
+                    &Remainder);
+  if (Remainder != 0) {
+    NumberOfTicks += 1;
+  }
+  NumberOfTicks += 1;
+
+  while (NumberOfTicks != 0) {
+
+    mMetronome->WaitForTick (mMetronome, 1);
+
+    Status = This->Io.Read (This, Width, Address, 1, Result);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+
+    if ((*Result & Mask) == Value) {
+      return EFI_SUCCESS;
+    }
+
+    NumberOfTicks -= 1;
+  }
+  return EFI_TIMEOUT;
+}
+
+/**
+  Enables a PCI driver to access PCI controller registers in the PCI root
+  bridge memory space.
+
+  The Mem.Read(), and Mem.Write() functions enable a driver to access PCI
+  controller registers in the PCI root bridge memory space.
+  The memory operations are carried out exactly as requested. The caller is
+  responsible for satisfying any alignment and memory width restrictions that a
+  PCI Root Bridge on a platform might require.
+
+  @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in]   Width     Signifies the width of the memory operation.
+  @param[in]   Address   The base address of the memory operation. The caller
+                         is responsible for aligning the Address if required.
+  @param[in]   Count     The number of memory operations to perform. Bytes
+                         moved is Width size * Count, starting at Address.
+  @param[out]  Buffer    For read operations, the destination buffer to store
+                         the results. For write operations, the source buffer
+                         to write data from.
+
+  @retval EFI_SUCCESS            The data was read from or written to the PCI
+                                 root bridge.
+  @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+  @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a
+                                 lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMemRead (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  OUT    VOID                                   *Buffer
+  )
+{
+  return RootBridgeIoMemRW (This, FALSE, Width, Address, Count, Buffer);
+}
+
+/**
+  Enables a PCI driver to access PCI controller registers in the PCI root
+  bridge memory space.
+
+  The Mem.Read(), and Mem.Write() functions enable a driver to access PCI
+  controller registers in the PCI root bridge memory space.
+  The memory operations are carried out exactly as requested. The caller is
+  responsible for satisfying any alignment and memory width restrictions that a
+  PCI Root Bridge on a platform might require.
+
+  @param[in]   This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in]   Width     Signifies the width of the memory operation.
+  @param[in]   Address   The base address of the memory operation. The caller
+                         is responsible for aligning the Address if required.
+  @param[in]   Count     The number of memory operations to perform. Bytes
+                         moved is Width size * Count, starting at Address.
+  @param[in]   Buffer    For read operations, the destination buffer to store
+                         the results. For write operations, the source buffer
+                         to write data from.
+
+  @retval EFI_SUCCESS            The data was read from or written to the PCI
+                                 root bridge.
+  @retval EFI_INVALID_PARAMETER  Width is invalid for this PCI root bridge.
+  @retval EFI_INVALID_PARAMETER  Buffer is NULL.
+  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a
+                                 lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMemWrite (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  IN     VOID                                   *Buffer
+  )
+{
+  return RootBridgeIoMemRW (This, TRUE, Width, Address, Count, Buffer);
+}
+
+/**
+  Enables a PCI driver to access PCI controller registers in the PCI root
+  bridge I/O space.
+
+  @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in]   Width       Signifies the width of the memory operations.
+  @param[in]   Address     The base address of the I/O operation. The caller is
+                           responsible for aligning the Address if required.
+  @param[in]   Count       The number of I/O operations to perform. Bytes moved
+                           is Width size * Count, starting at Address.
+  @param[out]  Buffer      For read operations, the destination buffer to store
+                           the results. For write operations, the source buffer
+                           to write data from.
+
+  @retval EFI_SUCCESS              The data was read from or written to the PCI
+                                   root bridge.
+  @retval EFI_INVALID_PARAMETER    Width is invalid for this PCI root bridge.
+  @retval EFI_INVALID_PARAMETER    Buffer is NULL.
+  @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a
+                                   lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoIoRead (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN     UINT64                                 Address,
+  IN     UINTN                                  Count,
+  OUT    VOID                                   *Buffer
+  )
+{
+  return RootBridgeIoIoRW (This, FALSE, Width, Address, Count, Buffer);
+}
+
+/**
+  Enables a PCI driver to access PCI controller registers in the PCI root
+  bridge I/O space.
+
+  @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in]   Width       Signifies the width of the memory operations.
+  @param[in]   Address     The base address of the I/O operation. The caller is
+                           responsible for aligning the Address if required.
+  @param[in]   Count       The number of I/O operations to perform. Bytes moved
+                           is Width size * Count, starting at Address.
+  @param[in]   Buffer      For read operations, the destination buffer to store
+                           the results. For write operations, the source buffer
+                           to write data from.
+
+  @retval EFI_SUCCESS              The data was read from or written to the PCI
+                                   root bridge.
+  @retval EFI_INVALID_PARAMETER    Width is invalid for this PCI root bridge.
+  @retval EFI_INVALID_PARAMETER    Buffer is NULL.
+  @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a
+                                   lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoIoWrite (
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL         *This,
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH   Width,
+  IN       UINT64                                  Address,
+  IN       UINTN                                   Count,
+  IN       VOID                                    *Buffer
+  )
+{
+  return RootBridgeIoIoRW (This, TRUE, Width, Address, Count, Buffer);
+}
+
+/**
+  Enables a PCI driver to copy one region of PCI root bridge memory space to
+  another region of PCI root bridge memory space.
+
+  The CopyMem() function enables a PCI driver to copy one region of PCI root
+  bridge memory space to another region of PCI root bridge memory space. This
+  is especially useful for video scroll operation on a memory mapped video
+  buffer.
+  The memory operations are carried out exactly as requested. The caller is
+  responsible for satisfying any alignment and memory width restrictions that a
+  PCI root bridge on a platform might require.
+
+  @param[in] This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+                         instance.
+  @param[in] Width       Signifies the width of the memory operations.
+  @param[in] DestAddress The destination address of the memory operation. The
+                         caller is responsible for aligning the DestAddress if
+                         required.
+  @param[in] SrcAddress  The source address of the memory operation. The caller
+                         is responsible for aligning the SrcAddress if
+                         required.
+  @param[in] Count       The number of memory operations to perform. Bytes
+                         moved is Width size * Count, starting at DestAddress
+                         and SrcAddress.
+
+  @retval  EFI_SUCCESS             The data was copied from one memory region
+                                   to another memory region.
+  @retval  EFI_INVALID_PARAMETER   Width is invalid for this PCI root bridge.
+  @retval  EFI_OUT_OF_RESOURCES    The request could not be completed due to a
+                                   lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoCopyMem (
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL              *This,
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH        Width,
+  IN UINT64                                       DestAddress,
+  IN UINT64                                       SrcAddress,
+  IN UINTN                                        Count
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     Direction;
+  UINTN       Stride;
+  UINTN       Index;
+  UINT64      Result;
+
+  if ((UINTN) Width > (UINTN) EfiPciWidthUint64) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (DestAddress == SrcAddress) {
+    return EFI_SUCCESS;
+  }
+
+  Stride = (UINTN) (1 << Width);
+
+  Direction = TRUE;
+  if ((DestAddress > SrcAddress) &&
+      (DestAddress < (SrcAddress + Count * Stride))) {
+    Direction   = FALSE;
+    SrcAddress  = SrcAddress  + (Count - 1) * Stride;
+    DestAddress = DestAddress + (Count - 1) * Stride;
+  }
+
+  for (Index = 0; Index < Count; Index ++) {
+
+    Status = RootBridgeIoMemRead (This, Width, SrcAddress, 1, &Result);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+
+    Status = RootBridgeIoMemWrite (This, Width, DestAddress, 1, &Result);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+
+    if (Direction) {
+      SrcAddress  += Stride;
+      DestAddress += Stride;
+    } else {
+      SrcAddress  -= Stride;
+      DestAddress -= Stride;
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Allows read from PCI configuration space.
+
+  @param This     A pointer to EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+  @param Width    Signifies the width of the memory operation.
+  @param Address  The address within the PCI configuration space
+                  for the PCI controller.
+  @param Count    The number of PCI configuration operations
+                  to perform.
+  @param Buffer   The destination buffer to store the results.
+
+  @retval EFI_SUCCESS           The data was read from the PCI root bridge.
+  @retval EFI_INVALID_PARAMETER Invalid parameters found.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPciRead (
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN       UINT64                                 Address,
+  IN       UINTN                                  Count,
+  OUT      VOID                                   *Buffer
+  )
+{
+  return RootBridgeIoPciRW (This, FALSE, Width, Address, Count, Buffer);
+}
+
+/**
+  Allows write to PCI configuration space.
+
+  @param This     A pointer to EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL
+  @param Width    Signifies the width of the memory operation.
+  @param Address  The address within the PCI configuration space
+                  for the PCI controller.
+  @param Count    The number of PCI configuration operations
+                  to perform.
+  @param Buffer   The source buffer to get the results.
+
+  @retval EFI_SUCCESS            The data was written to the PCI root bridge.
+  @retval EFI_INVALID_PARAMETER  Invalid parameters found.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoPciWrite (
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL        *This,
+  IN       EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_WIDTH  Width,
+  IN       UINT64                                 Address,
+  IN       UINTN                                  Count,
+  IN OUT   VOID                                  *Buffer
+  )
+{
+  return RootBridgeIoPciRW (This, TRUE, Width, Address, Count, Buffer);
+}
+
+/**
+  Provides the PCI controller-specific address needed to access
+  system memory for DMA.
+
+  @param This           A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param Operation      Indicate if the bus master is going to read or write
+                        to system memory.
+  @param HostAddress    The system memory address to map on the PCI controller.
+  @param NumberOfBytes  On input the number of bytes to map.
+                        On output the number of bytes that were mapped.
+  @param DeviceAddress  The resulting map address for the bus master PCI
+                        controller to use to access the system memory's HostAddress.
+  @param Mapping        The value to pass to Unmap() when the bus master DMA
+                        operation is complete.
+
+  @retval EFI_SUCCESS            Success.
+  @retval EFI_INVALID_PARAMETER  Invalid parameters found.
+  @retval EFI_UNSUPPORTED        The HostAddress cannot be mapped as a common buffer.
+  @retval EFI_DEVICE_ERROR       The System hardware could not map the requested address.
+  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to lack of resources.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoMap (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL            *This,
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL_OPERATION  Operation,
+  IN     VOID                                       *HostAddress,
+  IN OUT UINTN                                      *NumberOfBytes,
+  OUT    EFI_PHYSICAL_ADDRESS                       *DeviceAddress,
+  OUT    VOID                                       **Mapping
+  )
+{
+  EFI_PHYSICAL_ADDRESS  PhysicalAddress;
+
+  if (HostAddress == NULL || NumberOfBytes == NULL ||
+      DeviceAddress == NULL || Mapping == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Initialize the return values to their defaults
+  //
+  *Mapping = NULL;
+
+  //
+  // Make sure that Operation is valid
+  //
+  if ((UINT32) Operation >= EfiPciOperationMaximum) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  PhysicalAddress = (EFI_PHYSICAL_ADDRESS) (UINTN) HostAddress;
+  //
+  // The transfer is below 4GB, so the DeviceAddress is simply the HostAddress
+  //
+  *DeviceAddress = PhysicalAddress;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Completes the Map() operation and releases any corresponding resources.
+
+  The Unmap() function completes the Map() operation and releases any
+  corresponding resources.
+  If the operation was an EfiPciOperationBusMasterWrite or
+  EfiPciOperationBusMasterWrite64, the data is committed to the target system
+  memory.
+  Any resources used for the mapping are freed.
+
+  @param[in] This      A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[in] Mapping   The mapping value returned from Map().
+
+  @retval EFI_SUCCESS            The range was unmapped.
+  @retval EFI_INVALID_PARAMETER  Mapping is not a value that was returned by Map().
+  @retval EFI_DEVICE_ERROR       The data was not committed to the target system memory.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoUnmap (
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN VOID                             *Mapping
+  )
+{
+  MAP_INFO    *MapInfo;
+
+  //
+  // See if the Map() operation associated with this Unmap() required a mapping buffer.
+  // If a mapping buffer was not required, then this function simply returns EFI_SUCCESS.
+  //
+  if (Mapping != NULL) {
+    //
+    // Get the MAP_INFO structure from Mapping
+    //
+    MapInfo = (MAP_INFO *) Mapping;
+
+    //
+    // If this is a write operation from the Bus Master's point of view,
+    // then copy the contents of the mapped buffer into the real buffer
+    // so the processor can read the contents of the real buffer.
+    //
+    if (MapInfo->Operation == EfiPciOperationBusMasterWrite ||
+        MapInfo->Operation == EfiPciOperationBusMasterWrite64) {
+      CopyMem (
+        (VOID *) (UINTN) MapInfo->HostAddress,
+        (VOID *) (UINTN) MapInfo->MappedHostAddress,
+        MapInfo->NumberOfBytes
+        );
+    }
+
+    //
+    // Free the mapped buffer and the MAP_INFO structure.
+    //
+    gBS->FreePages (MapInfo->MappedHostAddress, MapInfo->NumberOfPages);
+    gBS->FreePool (Mapping);
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Allocates pages that are suitable for an EfiPciOperationBusMasterCommonBuffer
+  or EfiPciOperationBusMasterCommonBuffer64 mapping.
+
+  @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param Type        This parameter is not used and must be ignored.
+  @param MemoryType  The type of memory to allocate, EfiBootServicesData or
+                     EfiRuntimeServicesData.
+  @param Pages       The number of pages to allocate.
+  @param HostAddress A pointer to store the base system memory address of the
+                     allocated range.
+  @param Attributes  The requested bit mask of attributes for the allocated
+                     range. Only the attributes
+                     EFI_PCI_ATTRIBUTE_MEMORY_WRITE_COMBINE,
+                     EFI_PCI_ATTRIBUTE_MEMORY_CACHED, and
+                     EFI_PCI_ATTRIBUTE_DUAL_ADDRESS_CYCLE may be used with this
+                     function.
+
+  @retval EFI_SUCCESS            The requested memory pages were allocated.
+  @retval EFI_INVALID_PARAMETER  MemoryType is invalid.
+  @retval EFI_INVALID_PARAMETER  HostAddress is NULL.
+  @retval EFI_UNSUPPORTED        Attributes is unsupported. The only legal
+                                 attribute bits are MEMORY_WRITE_COMBINE,
+                                 MEMORY_CACHED, and DUAL_ADDRESS_CYCLE.
+  @retval EFI_OUT_OF_RESOURCES   The memory pages could not be allocated.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoAllocateBuffer (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN  EFI_ALLOCATE_TYPE                Type,
+  IN  EFI_MEMORY_TYPE                  MemoryType,
+  IN  UINTN                            Pages,
+  OUT VOID                             **HostAddress,
+  IN  UINT64                           Attributes
+  )
+{
+  EFI_STATUS            Status;
+  EFI_PHYSICAL_ADDRESS  PhysicalAddress;
+
+  //
+  // Validate Attributes
+  //
+  if ((Attributes & EFI_PCI_ATTRIBUTE_INVALID_FOR_ALLOCATE_BUFFER) != 0) {
+    return EFI_UNSUPPORTED;
+  }
+
+  //
+  // Check for invalid inputs
+  //
+  if (HostAddress == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // The only valid memory types are EfiBootServicesData and EfiRuntimeServicesData
+  //
+  if (MemoryType != EfiBootServicesData &&
+      MemoryType != EfiRuntimeServicesData) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  PhysicalAddress = (EFI_PHYSICAL_ADDRESS) (0xFFFFFFFFFFFFFFFFULL);
+
+  Status = gBS->AllocatePages (
+                  AllocateMaxAddress,
+                  MemoryType,
+                  Pages,
+                  &PhysicalAddress
+                  );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  *HostAddress = (VOID *) (UINTN) PhysicalAddress;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Frees memory that was allocated with AllocateBuffer().
+
+  The FreeBuffer() function frees memory that was allocated with
+  AllocateBuffer().
+
+  @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param Pages       The number of pages to free.
+  @param HostAddress The base system memory address of the allocated range.
+
+  @retval EFI_SUCCESS            The requested memory pages were freed.
+  @retval EFI_INVALID_PARAMETER  The memory range specified by HostAddress and
+                                 Pages was not allocated with AllocateBuffer().
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoFreeBuffer (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN  UINTN                            Pages,
+  OUT VOID                             *HostAddress
+  )
+{
+  return gBS->FreePages ((EFI_PHYSICAL_ADDRESS) (UINTN) HostAddress, Pages);
+}
+
+/**
+  Flushes all PCI posted write transactions from a PCI host bridge to system
+  memory.
+
+  The Flush() function flushes any PCI posted write transactions from a PCI
+  host bridge to system memory. Posted write transactions are generated by PCI
+  bus masters when they perform write transactions to target addresses in
+  system memory.
+  This function does not flush posted write transactions from any PCI bridges.
+  A PCI controller specific action must be taken to guarantee that the posted
+  write transactions have been flushed from the PCI controller and from all the
+  PCI bridges into the PCI host bridge. This is typically done with a PCI read
+  transaction from the PCI controller prior to calling Flush().
+
+  @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+
+  @retval EFI_SUCCESS        The PCI posted write transactions were flushed
+                             from the PCI host bridge to system memory.
+  @retval EFI_DEVICE_ERROR   The PCI posted write transactions were not flushed
+                             from the PCI host bridge due to a hardware error.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoFlush (
+  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL           *This
+  )
+{
+  return EFI_SUCCESS;
+}
+
+/**
+  Gets the attributes that a PCI root bridge supports setting with
+  SetAttributes(), and the attributes that a PCI root bridge is currently
+  using.
+
+  The GetAttributes() function returns the mask of attributes that this PCI
+  root bridge supports and the mask of attributes that the PCI root bridge is
+  currently using.
+
+  @param This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param Supported   A pointer to the mask of attributes that this PCI root
+                     bridge supports setting with SetAttributes().
+  @param Attributes  A pointer to the mask of attributes that this PCI root
+                     bridge is currently using.
+
+  @retval  EFI_SUCCESS           If Supports is not NULL, then the attributes
+                                 that the PCI root bridge supports is returned
+                                 in Supports. If Attributes is not NULL, then
+                                 the attributes that the PCI root bridge is
+                                 currently using is returned in Attributes.
+  @retval  EFI_INVALID_PARAMETER Both Supports and Attributes are NULL.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoGetAttributes (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  OUT UINT64                           *Supported,
+  OUT UINT64                           *Attributes
+  )
+{
+  PCI_ROOT_BRIDGE_INSTANCE *RootBridgeInstance;
+
+  RootBridgeInstance = ROOT_BRIDGE_FROM_THIS (This);
+
+  if (Attributes == NULL && Supported == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Set the return value for Supported and Attributes
+  //
+  if (Supported != NULL) {
+    *Supported  = RootBridgeInstance->RootBridge.Supports;
+  }
+
+  if (Attributes != NULL) {
+    *Attributes = RootBridgeInstance->RootBridge.Attributes;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Sets attributes for a resource range on a PCI root bridge.
+
+  The SetAttributes() function sets the attributes specified in Attributes for
+  the PCI root bridge on the resource range specified by ResourceBase and
+  ResourceLength. Since the granularity of setting these attributes may vary
+  from resource type to resource type, and from platform to platform, the
+  actual resource range and the one passed in by the caller may differ. As a
+  result, this function may set the attributes specified by Attributes on a
+  larger resource range than the caller requested. The actual range is returned
+  in ResourceBase and ResourceLength. The caller is responsible for verifying
+  that the actual range for which the attributes were set is acceptable.
+
+  @param This            A pointer to the
+                         EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param Attributes      The mask of attributes to set. If the
+                         attribute bit MEMORY_WRITE_COMBINE,
+                         MEMORY_CACHED, or MEMORY_DISABLE is set,
+                         then the resource range is specified by
+                         ResourceBase and ResourceLength. If
+                         MEMORY_WRITE_COMBINE, MEMORY_CACHED, and
+                         MEMORY_DISABLE are not set, then
+                         ResourceBase and ResourceLength are ignored,
+                         and may be NULL.
+  @param ResourceBase    A pointer to the base address of the
+                         resource range to be modified by the
+                         attributes specified by Attributes.
+  @param ResourceLength  A pointer to the length of the resource
+                                   range to be modified by the attributes
+                                   specified by Attributes.
+
+  @retval  EFI_SUCCESS           The current configuration of this PCI root bridge
+                                 was returned in Resources.
+  @retval  EFI_UNSUPPORTED       The current configuration of this PCI root bridge
+                                 could not be retrieved.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoSetAttributes (
+  IN     EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *This,
+  IN     UINT64                           Attributes,
+  IN OUT UINT64                           *ResourceBase,
+  IN OUT UINT64                           *ResourceLength
+  )
+{
+  PCI_ROOT_BRIDGE_INSTANCE            *RootBridgeInstance;
+
+  RootBridgeInstance = ROOT_BRIDGE_FROM_THIS (This);
+
+  // Then check optional parameters if eligible
+  if ((Attributes & (EFI_PCI_ATTRIBUTE_MEMORY_WRITE_COMBINE |
+                    EFI_PCI_ATTRIBUTE_MEMORY_CACHED |
+                    EFI_PCI_ATTRIBUTE_MEMORY_DISABLE)) != 0) {
+    if (ResourceBase == NULL || ResourceLength == NULL) {
+      return EFI_INVALID_PARAMETER;
+    }
+  }
+
+  if (Attributes != 0) {
+    if ((Attributes & (~(RootBridgeInstance->RootBridge.Supports))) != 0) {
+      return EFI_UNSUPPORTED;
+    }
+  }
+
+  //
+  // This is a generic driver for a PC-AT class system.  It does not have any
+  // chipset specific knowlegde, so none of the attributes can be set or
+  // cleared.  Any attempt to set attribute that are already set will succeed,
+  // and any attempt to set an attribute that is not supported will fail.
+  //
+  if (Attributes & (~RootBridgeInstance->RootBridge.Attributes)) {
+    return EFI_UNSUPPORTED;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Retrieves the current resource settings of this PCI root bridge in the form
+  of a set of ACPI resource descriptors.
+
+  There are only two resource descriptor types from the ACPI Specification that
+  may be used to describe the current resources allocated to a PCI root bridge.
+  These are the QWORD Address Space Descriptor, and the End Tag. The QWORD
+  Address Space Descriptor can describe memory, I/O, and bus number ranges for
+  dynamic or fixed resources. The configuration of a PCI root bridge is described
+  with one or more QWORD Address Space Descriptors followed by an End Tag.
+
+  @param[in]   This        A pointer to the EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL.
+  @param[out]  Resources   A pointer to the resource descriptors that
+                           describe the current configuration of this PCI root
+                           bridge. The storage for the resource
+                           descriptors is allocated by this function. The
+                           caller must treat the return buffer as read-only
+                           data, and the buffer must not be freed by the
+                          caller.
+
+  @retval  EFI_SUCCESS     The current configuration of this PCI root bridge
+                           was returned in Resources.
+  @retval  EFI_UNSUPPORTED The current configuration of this PCI root bridge
+                           could not be retrieved.
+**/
+EFI_STATUS
+EFIAPI
+RootBridgeIoConfiguration (
+  IN  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL     *This,
+  OUT VOID                                **Resources
+  )
+{
+  PCI_ROOT_BRIDGE_INSTANCE          *RootBridgeInstance;
+  PCI_RES_NODE                      *ResAllocNode;
+  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Descriptor;
+  EFI_ACPI_END_TAG_DESCRIPTOR       *End;
+  UINTN                             Index;
+
+  RootBridgeInstance = ROOT_BRIDGE_FROM_THIS (This);
+  ZeroMem (
+    RootBridgeInstance->ConfigBuffer,
+    rtMaxRes * sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) + sizeof (EFI_ACPI_END_TAG_DESCRIPTOR)
+    );
+
+  Descriptor = RootBridgeInstance->ConfigBuffer;
+  for (Index = rtBus; Index < rtMaxRes; Index++) {
+
+    ResAllocNode = &RootBridgeInstance->ResAllocNode[Index];
+
+    if (ResAllocNode->Status != ResAllocated) {
+      continue;
+    }
+
+    Descriptor->Desc          = ACPI_ADDRESS_SPACE_DESCRIPTOR;
+    Descriptor->Len           = sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) - 3;
+    Descriptor->AddrRangeMin  = ResAllocNode->Base;
+    Descriptor->AddrRangeMax  = ResAllocNode->Base + ResAllocNode->Length - 1;
+    Descriptor->AddrLen       = ResAllocNode->Length;
+
+    switch (ResAllocNode->Type) {
+
+    case rtBus:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_BUS;
+      break;
+
+    case rtIo16:
+    case rtIo32:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_IO;
+      Descriptor->AddrSpaceGranularity = 32;
+      break;
+
+    case rtMmio32:
+    case rtMmio32p:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_MEM;
+      Descriptor->SpecificFlag         = (Index == rtMmio32) ? 0 :
+                                           EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE;
+      Descriptor->AddrSpaceGranularity = 32;
+    break;
+
+    case rtMmio64:
+    case rtMmio64p:
+      Descriptor->ResType              = ACPI_ADDRESS_SPACE_TYPE_MEM;
+      Descriptor->SpecificFlag         = (Index == rtMmio64) ? 0 :
+                                           EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE;
+      Descriptor->AddrSpaceGranularity = 64;
+      break;
+
+    default:
+      break;
+    };
+
+    Descriptor++;
+  }
+
+  //
+  // Terminate the entries.
+  //
+  End = (EFI_ACPI_END_TAG_DESCRIPTOR *) Descriptor;
+  End->Desc     = ACPI_END_TAG_DESCRIPTOR;
+  End->Checksum = 0x0;
+
+  *Resources = RootBridgeInstance->ConfigBuffer;
+
+  return EFI_SUCCESS;
+}
-- 
2.17.1


  parent reply	other threads:[~2020-12-09  9:24 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-09  9:24 [edk2-platforms][PATCH 00/34] Add new Ampere Mt. Jade platform Nhi Pham
2020-12-09  9:24 ` [edk2-platforms][PATCH 01/34] Initial support for Ampere Altra and " Nhi Pham
2021-01-07 23:57   ` [edk2-devel] " Leif Lindholm
2021-01-15  4:59     ` Vu Nguyen
2020-12-09  9:24 ` [edk2-platforms][PATCH 02/34] Platform/Ampere: Implement FailSafe library Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 03/34] Platform/Ampere: Add FailSafe and WDT support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 04/34] AmpereAltraPkg: Implement GpioLib and I2cLib modules Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 05/34] JadePkg: Implement RealTimeClockLib for PCF85063 Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 06/34] Platform/Ampere: Add AcpiPccLib to support ACPI PCCT Table Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 07/34] Platform/Ampere: Add AcpiHelperLib to update ACPI DSDT table Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 08/34] JadePkg: Initial support for static ACPI tables Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 09/34] JadePkg: Install some ACPI tables at runtime Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 10/34] Silicon/Ampere: Support Non Volatile storage for Variable service Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 11/34] Silicon/Ampere: Support PlatformManagerUiLib Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 12/34] AmpereAltraPkg: Add PcieCore Library Nhi Pham
2020-12-09  9:25 ` Nhi Pham [this message]
2020-12-09  9:25 ` [edk2-platforms][PATCH 14/34] JadePkg: Add implementation for PcieBoardLib Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 15/34] JadePkg: Enable PCIe support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 16/34] JadePkg: Add ASpeed GOP driver Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 17/34] Silicon/Ampere: Add Random Number Generator Support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 18/34] Silicon/Ampere: Fixup runtime memory attribute Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 19/34] JadePkg: Add SMBIOS tables support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 20/34] AmpereAltraPkg: Add DebugInfoPei module Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 21/34] Silicon/Ampere: Add platform info screen Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 22/34] Silicon/Ampere: Add Memory " Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 23/34] AmpereAltraPkg: Add CPU Configuration for SubNUMA Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 24/34] AmpereAltraPkg: Add ACPI configuration screen Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 25/34] AmpereAltraPkg: Implement PlatformFlashAccessLib instance Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 26/34] JadePkg: Add implementation for UEFI Capsule Update Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 27/34] JadePkg: Add Capsule Update support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 28/34] Silicon/Ampere: Implement PlatformBootManagerLib for LinuxBoot Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 29/34] Platform/Ampere: Add LinuxBoot image Nhi Pham
2020-12-10 12:40   ` [edk2-devel] " Leif Lindholm
2020-12-11  2:38     ` Nhi Pham
2020-12-11 11:15       ` Leif Lindholm
2020-12-09  9:25 ` [edk2-platforms][PATCH 30/34] JadePkg: Support LinuxBoot DSC/FDF build for Jade platform Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 31/34] AmpereAltraPkg: Add BootProgress support Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 32/34] JadePkg: Add ACPI/APEI tables Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 33/34] Platform/Ampere: Add AcpiApeiLib Nhi Pham
2020-12-09  9:25 ` [edk2-platforms][PATCH 34/34] AmpereAltraPkg, JadePkg: Add RAS setting screen Nhi Pham

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-list from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201209092531.30867-14-nhi@os.amperecomputing.com \
    --to=devel@edk2.groups.io \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox