[RFC 1/6] MdeModulePkg: Add DxeBmDmaLib library

[Leo Duran <leo.duran@amd.com>]

This patch provides an abstraction layer for DMA operations implemented
by the PciHostBridgeDxe driver. The intent is to then allow override of
this library as may be required by specific hardware implementations,
such as AMD's Secure Encrypted Virtualization (SEV).

This new (BmDmaLib class) library is modeled after the existing DmaLib
plus an extra DmaAbove4GB (BOOLEAN) parameter in the Map and Allocate
interfaces, so that decisions can be made about the need to allocate DMA
buffers below the 4GB boundary.

Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Leo Duran  <leo.duran@amd.com>
---
 MdeModulePkg/Include/Library/BmDmaLib.h          | 161 +++++++++++
 MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.c   | 351 +++++++++++++++++++++++
 MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf |  41 +++
 MdeModulePkg/MdeModulePkg.dsc                    |   1 +
 4 files changed, 554 insertions(+)
 create mode 100644 MdeModulePkg/Include/Library/BmDmaLib.h
 create mode 100644 MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.c
 create mode 100644 MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf

diff --git a/MdeModulePkg/Include/Library/BmDmaLib.h b/MdeModulePkg/Include/Library/BmDmaLib.h
new file mode 100644
index 0000000..2c0e50f
--- /dev/null
+++ b/MdeModulePkg/Include/Library/BmDmaLib.h
@@ -0,0 +1,161 @@
+/** @file
+  DMA abstraction library APIs. Based on PCI IO protocol DMA abstractions.
+
+  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
+  Copyright (c) 2017, AMD Inc. All rights reserved.<BR>
+
+  DMA Bus Master Read Operation:
+    Call BmDmaMap() for DmaOperationBusMasterRead.
+    Program the DMA Bus Master with the DeviceAddress returned by BmDmaMap().
+    Start the DMA Bus Master.
+    Wait for DMA Bus Master to complete the read operation.
+    Call BmDmaUnmap().
+
+  DMA Bus Master Write Operation:
+    Call BmDmaMap() for DmaOperationBusMasterWrite.
+    Program the DMA Bus Master with the DeviceAddress returned by BmDmaMap().
+    Start the DMA Bus Master.
+    Wait for DMA Bus Master to complete the write operation.
+    Call BmDmaUnmap().
+
+  DMA Bus Master Common Buffer Operation:
+    Call BmDmaAllocateBuffer() to allocate a common buffer.
+    Call BmDmaMap() for DmaOperationBusMasterCommonBuffer.
+    Program the DMA Bus Master with the DeviceAddress returned by BmDmaMap().
+    The common buffer can now be accessed equally by the processor and the DMA bus master.
+    Call BmDmaUnmap().
+    Call BmDmaFreeBuffer().
+
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+ Derived from:
+   EmbeddedPkg/Include/Library/DmaLib.h
+
+**/
+
+#ifndef __BM_DMA_LIB_H__
+#define __BM_DMA_LIB_H__
+
+
+typedef enum {
+  ///
+  /// A read operation from system memory by a bus master.
+  ///
+  DmaOperationBusMasterRead,
+  ///
+  /// A write operation from system memory by a bus master.
+  ///
+  DmaOperationBusMasterWrite,
+  ///
+  /// Provides both read and write access to system memory by both the processor and a
+  /// bus master. The buffer is coherent from both the processor's and the bus master's point of view.
+  ///
+  DmaOperationBusMasterCommonBuffer,
+  DmaOperationBusMasterMaximum
+} BM_DMA_OPERATION;
+
+
+/**
+  Provides the DMA controller-specific addresses needed to access system memory.
+
+  Operation is relative to the DMA bus master.
+
+  @param  DmaAbove4GB           Indicates capability of DMA operations above 4GB.
+  @param  Operation             Indicates if the bus master is going to read or write to system memory.
+  @param  HostAddress           The system memory address to map to the DMA 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 controller to use to
+                                access the hosts HostAddress.
+  @param  Mapping               A resulting value to pass to BmDmaUnmap().
+
+  @retval EFI_SUCCESS           The range was mapped for the returned NumberOfBytes.
+  @retval EFI_UNSUPPORTED       The HostAddress cannot be mapped as a common buffer.
+  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
+  @retval EFI_OUT_OF_RESOURCES  The request could not be completed due to a lack of resources.
+  @retval EFI_DEVICE_ERROR      The system hardware could not map the requested address.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaMap (
+  IN     BOOLEAN           DmaAbove4GB,
+  IN     BM_DMA_OPERATION  Operation,
+  IN     VOID              *HostAddress,
+  IN OUT UINTN             *NumberOfBytes,
+  OUT    PHYSICAL_ADDRESS  *DeviceAddress,
+  OUT    VOID              **Mapping
+  );
+
+
+/**
+  Completes the DmaOperationBusMasterRead/Write/CommonBuffer operation
+  and releases any corresponding resources.
+
+  @param  Mapping               The mapping value returned from BmDmaMap().
+
+  @retval EFI_SUCCESS           The range was unmapped.
+  @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaUnmap (
+  IN  VOID                 *Mapping
+  );
+
+
+/**
+  Allocates pages that are suitable for a BmDmaMap() of type DmaOperationBusMasterCommonBuffer.
+
+  @param  DmaAbove4GB           Indicates capability of DMA operations above 4GB.
+  @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.
+
+  @retval EFI_SUCCESS           The requested memory pages were allocated.
+  @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
+                                MEMORY_WRITE_COMBINE and MEMORY_CACHED.
+  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
+  @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaAllocateBuffer (
+  IN  BOOLEAN              DmaAbove4GB,
+  IN  EFI_MEMORY_TYPE      MemoryType,
+  IN  UINTN                Pages,
+  OUT VOID                 **HostAddress
+  );
+
+
+/**
+  Frees memory that was allocated with BmDmaAllocateBuffer().
+
+  @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 BmDmaAllocateBuffer().
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaFreeBuffer (
+  IN  UINTN                Pages,
+  IN  VOID                 *HostAddress
+  );
+
+
+#endif
+
diff --git a/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.c b/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.c
new file mode 100644
index 0000000..824b51f
--- /dev/null
+++ b/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.c
@@ -0,0 +1,351 @@
+/** @file
+  DMA abstraction library APIs. Based on PCI IO protocol DMA abstractions.
+
+  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
+  Copyright (c) 2017, AMD Inc. All rights reserved.<BR>
+
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+  Derived from:
+   MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
+
+**/
+
+#include <PiDxe.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/BmDmaLib.h>
+
+
+#define FORCE_BELOW_4GB_TRUE   TRUE
+#define FORCE_BELOW_4GB_FALSE  FALSE
+#define NO_MAPPING             (VOID *) (UINTN) -1
+
+
+typedef struct {
+  BM_DMA_OPERATION      Operation;
+  UINTN                 NumberOfBytes;
+  UINTN                 NumberOfPages;
+  EFI_PHYSICAL_ADDRESS  HostAddress;
+  EFI_PHYSICAL_ADDRESS  MappedHostAddress;
+} MAP_INFO;
+
+
+EFI_STATUS
+AllocateBounceBuffer (
+  IN     BOOLEAN               ForceBelow4GB,
+  IN     BM_DMA_OPERATION      Operation,
+  IN     EFI_PHYSICAL_ADDRESS  HostAddress,
+  IN OUT UINTN                 *NumberOfBytes,
+  OUT    PHYSICAL_ADDRESS      *DeviceAddress,
+  OUT    VOID                  **Mapping
+  )
+{
+  EFI_STATUS         Status;
+  MAP_INFO           *MapInfo;
+  EFI_ALLOCATE_TYPE  AllocateType;
+
+  //
+  // Allocate a MAP_INFO structure to remember the mapping when Unmap() is
+  // called later.
+  //
+  MapInfo = AllocatePool (sizeof (MAP_INFO));
+  if (MapInfo == NULL) {
+    *NumberOfBytes = 0;
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  //
+  // Initialize the MAP_INFO structure
+  //
+  MapInfo->Operation     = Operation;
+  MapInfo->NumberOfBytes = *NumberOfBytes;
+  MapInfo->NumberOfPages = EFI_SIZE_TO_PAGES (MapInfo->NumberOfBytes);
+  MapInfo->HostAddress   = HostAddress;
+
+  if (ForceBelow4GB) {
+    //
+    // Limit allocations to memory below 4GB
+    //
+    AllocateType = AllocateMaxAddress;
+    MapInfo->MappedHostAddress = SIZE_4GB - 1;
+  } else {
+    AllocateType = AllocateAnyPages;
+  }
+
+  //
+  // Allocate DMA bounce buffer
+  //
+  Status = gBS->AllocatePages (
+                  AllocateType,
+                  EfiBootServicesData,
+                  MapInfo->NumberOfPages,
+                  &MapInfo->MappedHostAddress
+                  );
+
+  if (EFI_ERROR (Status)) {
+    FreePool (MapInfo);
+    *NumberOfBytes = 0;
+    return Status;
+  }
+
+  //
+  // If this is a read operation from the Bus Master's point of view,
+  // then copy the contents of the real buffer into the mapped buffer
+  // so the Bus Master can read the contents of the real buffer.
+  //
+  if (Operation ==  DmaOperationBusMasterRead) {
+    CopyMem (
+      (VOID *) (UINTN) MapInfo->MappedHostAddress,
+      (VOID *) (UINTN) MapInfo->HostAddress,
+      MapInfo->NumberOfBytes
+      );
+  }
+
+  //
+  // The DeviceAddress is the address of the mapped buffer
+  //
+  *DeviceAddress = MapInfo->MappedHostAddress;
+
+  //
+  // Return a pointer to the MAP_INFO structure in Mapping
+  //
+  *Mapping = MapInfo;
+
+  return EFI_SUCCESS;
+}
+
+
+/**
+  Provides the DMA controller-specific addresses needed to access system memory.
+
+  Operation is relative to the DMA bus master.
+
+  @param  DmaAbove4GB           Indicates capability of DMA operations above 4GB.
+  @param  Operation             Indicates if the bus master is going to read or write to system memory.
+  @param  HostAddress           The system memory address to map to the DMA 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 controller to use to
+                                access the hosts HostAddress.
+  @param  Mapping               A resulting value to pass to BmDmaUnmap().
+
+  @retval EFI_SUCCESS           The range was mapped for the returned NumberOfBytes.
+  @retval EFI_UNSUPPORTED       The HostAddress cannot be mapped as a common buffer.
+  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
+  @retval EFI_OUT_OF_RESOURCES  The request could not be completed due to a lack of resources.
+  @retval EFI_DEVICE_ERROR      The system hardware could not map the requested address.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaMap (
+  IN     BOOLEAN           DmaAbove4GB,
+  IN     BM_DMA_OPERATION  Operation,
+  IN     VOID              *HostAddress,
+  IN OUT UINTN             *NumberOfBytes,
+  OUT    PHYSICAL_ADDRESS  *DeviceAddress,
+  OUT    VOID              **Mapping
+  )
+{
+  EFI_PHYSICAL_ADDRESS  PhysicalAddress;
+
+  //
+  // Check for invalid inputs
+  //
+  if (HostAddress == NULL || NumberOfBytes == NULL || DeviceAddress == NULL ||
+      Mapping == NULL || (UINT32) Operation >= DmaOperationBusMasterMaximum) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  PhysicalAddress = (EFI_PHYSICAL_ADDRESS) (UINTN) HostAddress;
+  if (DmaAbove4GB || (PhysicalAddress + *NumberOfBytes) <= SIZE_4GB) {
+    //
+    // If we CAN handle DMA above 4GB or the transfer is below 4GB,
+    // the DeviceAddress is simply the HostAddress
+    //
+    *DeviceAddress = PhysicalAddress;
+    *Mapping       = NO_MAPPING;
+
+    return EFI_SUCCESS;
+  } 
+
+  //
+  // If we cannot handle DMA above 4GB and any part of the DMA transfer
+  // being is above 4GB, then map the DMA transfer to a buffer below 4GB.
+  //
+  if (Operation == DmaOperationBusMasterCommonBuffer) {
+    //
+    // Common Buffer operations cannot be remapped, so return an error.
+    //
+    return EFI_UNSUPPORTED;
+  }
+
+  return AllocateBounceBuffer ( 
+           Operation,
+           FORCE_BELOW_4GB_TRUE,   
+           PhysicalAddress,
+           NumberOfBytes,
+           DeviceAddress,
+           Mapping
+           );
+}
+
+
+/**
+  Completes the DmaOperationBusMasterRead/Write/CommonBuffer operation
+  and releases any corresponding resources.
+
+  @param  Mapping               The mapping value returned from BmDmaMap().
+
+  @retval EFI_SUCCESS           The range was unmapped.
+  @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaUnmap (
+  IN  VOID                 *Mapping
+  )
+{
+  MAP_INFO  *MapInfo;
+
+  //
+  // Check for invalid inputs
+  //
+  if (Mapping == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // 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 == NO_MAPPING) {
+    return EFI_SUCCESS;
+  }
+
+  //
+  // 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.
+  //
+  MapInfo = (MAP_INFO *)Mapping;
+  if (MapInfo->Operation == DmaOperationBusMasterWrite) {
+    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);
+  FreePool (Mapping);
+  return EFI_SUCCESS;
+}
+
+
+/**
+  Allocates pages that are suitable for a BmDmaMap() of type DmaOperationBusMasterCommonBuffer.
+
+  @param  DmaAbove4GB           Indicates capability of DMA operations above 4GB.
+  @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.
+
+  @retval EFI_SUCCESS           The requested memory pages were allocated.
+  @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
+                                MEMORY_WRITE_COMBINE and MEMORY_CACHED.
+  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
+  @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaAllocateBuffer (
+  IN  BOOLEAN              DmaAbove4GB,
+  IN  EFI_MEMORY_TYPE      MemoryType,
+  IN  UINTN                Pages,
+  OUT VOID                 **HostAddress
+  )
+{
+  EFI_STATUS           Status;
+  EFI_PHYSICAL_ADDRESS PhysicalAddress;
+  EFI_ALLOCATE_TYPE    AllocateType;
+
+  //
+  // 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;
+  }
+
+  if (DmaAbove4GB) {
+    AllocateType = AllocateAnyPages;
+  } else {
+    //
+    // Limit allocations to memory below 4GB
+    //
+    AllocateType    = AllocateMaxAddress;
+    PhysicalAddress = (EFI_PHYSICAL_ADDRESS) (SIZE_4GB - 1);
+  }
+  Status = gBS->AllocatePages (
+                  AllocateType,
+                  MemoryType,
+                  Pages,
+                  &PhysicalAddress
+                  );
+  if (!EFI_ERROR (Status)) {
+    *HostAddress = (VOID *) (UINTN) PhysicalAddress;
+  }
+
+  return Status;
+}
+
+
+/**
+  Frees memory that was allocated with BmDmaAllocateBuffer().
+
+  @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 BmDmaAllocateBuffer().
+
+**/
+EFI_STATUS
+EFIAPI
+BmDmaFreeBuffer (
+  IN  UINTN                Pages,
+  IN  VOID                 *HostAddress
+  )
+{
+  return gBS->FreePages ((EFI_PHYSICAL_ADDRESS) (UINTN) HostAddress, Pages);
+}
+
diff --git a/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf b/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf
new file mode 100644
index 0000000..06bb8b1
--- /dev/null
+++ b/MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf
@@ -0,0 +1,41 @@
+## @file
+#
+# DMA abstraction library APIs. Based on PCI IO protocol DMA abstractions.
+#
+#  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
+#  Copyright (c) 2017, AMD Inc. All rights reserved.<BR>
+#
+#  This program and the accompanying materials
+#  are licensed and made available under the terms and conditions of the BSD License
+#  which accompanies this distribution.  The full text of the license may be found at
+#  http://opensource.org/licenses/bsd-license.php
+#
+#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = DxeBmDmaLib
+  FILE_GUID                      = daa403e0-071d-44ef-95cf-7f2472e4a4d5
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = BmDmaLib
+
+[Sources.common]
+  DxeBmDmaLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  DxeServicesTableLib
+  MemoryAllocationLib
+  UefiBootServicesTableLib
+
+
diff --git a/MdeModulePkg/MdeModulePkg.dsc b/MdeModulePkg/MdeModulePkg.dsc
index 5996fe5..311922e 100644
--- a/MdeModulePkg/MdeModulePkg.dsc
+++ b/MdeModulePkg/MdeModulePkg.dsc
@@ -275,6 +275,7 @@ [Components]
   MdeModulePkg/Core/Pei/PeiMain.inf
   MdeModulePkg/Core/RuntimeDxe/RuntimeDxe.inf
 
+  MdeModulePkg/Library/DxeBmDmaLib/DxeBmDmaLib.inf
   MdeModulePkg/Library/DxeCapsuleLibNull/DxeCapsuleLibNull.inf
   MdeModulePkg/Library/UefiMemoryAllocationProfileLib/UefiMemoryAllocationProfileLib.inf
   MdeModulePkg/Library/DxeCoreMemoryAllocationLib/DxeCoreMemoryAllocationLib.inf
-- 
1.9.1