[RFC] [PATCH V3 1/3] MdeModulePkg/Include: Add IOMMU protocol definition.

[Jiewen Yao <jiewen.yao@intel.com>]

This protocol is to abstract DMA access from IOMMU.
1) Intel "DMAR" ACPI table.
2) AMD "IVRS" ACPI table
3) ARM "IORT" ACPI table.

There might be multiple IOMMU engines on one platform.
For example, one for graphic and one for rest PCI devices
(such as ATA/USB).
All IOMMU engines are reported by one ACPI table.

All IOMMU protocol provider should be based upon ACPI table.
This single IOMMU protocol can handle multiple IOMMU engines on one system.

This IOMMU protocol provider can use UEFI device path to distinguish
if the device is graphic or ATA/USB, and find out corresponding
IOMMU engine.

The IOMMU protocol provides 2 capabilities:
A) Set DMA access attribute - such as write/read control.
B) Remap DMA memory - such as remap above 4GiB system memory address
to below 4GiB device address.

4) AMD "SEV" feature.
We can have an AMD SEV specific IOMMU driver to produce IOMMU protocol,
and manage SEV bit in SetAttribute(), and return UNSUPPORTED
for SetRemapAddress/GetRemapAddress().

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Leo Duran <leo.duran@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
---
 MdeModulePkg/Include/Protocol/IoMmu.h | 196 ++++++++++++++++++++
 MdeModulePkg/MdeModulePkg.dec         |   3 +
 2 files changed, 199 insertions(+)

diff --git a/MdeModulePkg/Include/Protocol/IoMmu.h b/MdeModulePkg/Include/Protocol/IoMmu.h
new file mode 100644
index 0000000..766b918
--- /dev/null
+++ b/MdeModulePkg/Include/Protocol/IoMmu.h
@@ -0,0 +1,196 @@
+/** @file
+  EFI IOMMU Protocol.
+
+Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials are licensed and made available under
+the terms and conditions of the BSD License that 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.
+
+**/
+
+
+#ifndef __IOMMU_H__
+#define __IOMMU_H__
+
+//
+// IOMMU Protocol GUID value
+//
+#define EDKII_IOMMU_PROTOCOL_GUID \
+    { \
+      0x4e939de9, 0xd948, 0x4b0f, { 0x88, 0xed, 0xe6, 0xe1, 0xce, 0x51, 0x7c, 0x1e } \
+    }
+
+//
+// Forward reference for pure ANSI compatability
+//
+typedef struct _EDKII_IOMMU_PROTOCOL  EDKII_IOMMU_PROTOCOL;
+
+//
+// Revision The revision to which the IOMMU interface adheres.
+//          All future revisions must be backwards compatible.
+//          If a future version is not back wards compatible it is not the same GUID.
+//
+#define EDKII_IOMMU_PROTOCOL_REVISION 0x00010000
+
+//
+// IOMMU attribute.
+// These types can be "ORed" together as needed.
+// Any undefined bits are reserved and must be zero.
+//
+#define EDKII_IOMMU_ATTRIBUTE_READ   0x1
+#define EDKII_IOMMU_ATTRIBUTE_WRITE  0x2
+
+/**
+  Get IOMMU page size.
+
+  This is the minimal supported page size for a IOMMU.
+  For example, if an IOMMU supports 4KiB, 2MiB and 1GiB,
+  4KiB should be returned.
+
+  @param[in]  This      Protocol instance pointer.
+  @param[out] PageSize  The minimal supported page size for a IOMMU.
+
+  @retval EFI_SUCCESS            The page size is returned.
+  @retval EFI_INVALID_PARAMETER  PageSize is NULL.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EDKII_IOMMU_GET_PAGE_SIZE)(
+  IN  EDKII_IOMMU_PROTOCOL  *This,
+  OUT UINTN                 *PageSize
+  );
+
+/**
+  Set IOMMU attribute for a system memory.
+
+  If the IOMMU protocol exists, the system memory cannot be used
+  for DMA by default.
+
+  When a device requests a DMA access for a system memory,
+  the device driver need use SetAttribute() to update the IOMMU
+  attribute to request DMA access (read and/or write).
+
+  The DeviceHandle is used to identify which device submits the request.
+  The IOMMU implementation need translate the device path to an IOMMU device ID,
+  and set IOMMU hardware register accordingly.
+  1) DeviceHandle can be a standard PCI device.
+     The memory for BusMasterRead need set EDKII_IOMMU_ATTRIBUTE_READ.
+     The memory for BusMasterWrite need set EDKII_IOMMU_ATTRIBUTE_WRITE.
+     The memory for BusMasterCommonBuffer need set EDKII_IOMMU_ATTRIBUTE_READ|EDKII_IOMMU_ATTRIBUTE_WRITE.
+     After the memory is used, the memory need set 0 to keep it being protected.
+  2) DeviceHandle can be an ACPI device (ISA, I2C, SPI, etc).
+     The memory for DMA access need set EDKII_IOMMU_ATTRIBUTE_READ and/or EDKII_IOMMU_ATTRIBUTE_WRITE.
+
+  @param[in]  This              The protocol instance pointer.
+  @param[in]  DeviceHandle      The device who initiates the DMA access request.
+  @param[in]  DeviceAddress     The base of device memory address to be used as the DMA memory.
+  @param[in]  Length            The length of device memory address to be used as the DMA memory.
+  @param[in]  IoMmuAttribute    The IOMMU attribute.
+
+  @retval EFI_SUCCESS            The IoMmuAttribute is set for the memory range specified by DeviceAddress and Length.
+  @retval EFI_INVALID_PARAMETER  DeviceHandle is an invalid handle.
+  @retval EFI_INVALID_PARAMETER  DeviceAddress is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  Length is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  Length is 0.
+  @retval EFI_INVALID_PARAMETER  IoMmuAttribute specified an illegal combination of attributes.
+  @retval EFI_UNSUPPORTED        DeviceHandle is unknown by the IOMMU.
+  @retval EFI_UNSUPPORTED        The bit mask of IoMmuAttribute is not supported by the IOMMU.
+  @retval EFI_UNSUPPORTED        The IOMMU does not support the memory range specified by DeviceAddress and Length.
+  @retval EFI_OUT_OF_RESOURCES   There are not enough resources available to modify the IOMMU attribute.
+  @retval EFI_DEVICE_ERROR       The IOMMU device reported an error while attempting the operation.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EDKII_IOMMU_SET_ATTRIBUTE)(
+  IN EDKII_IOMMU_PROTOCOL  *This,
+  IN EFI_HANDLE            DeviceHandle,
+  IN EFI_PHYSICAL_ADDRESS  DeviceAddress,
+  IN UINT64                Length,
+  IN UINT64                IoMmuAttribute
+  );
+
+/**
+  Remap a device address to host address.
+
+  For example, this function may support map an above 4GiB host address
+  to a below 4GiB device address.
+
+  @param[in]  This              The protocol instance pointer.
+  @param[in]  DeviceHandle      The device who initiates the DMA access request.
+  @param[in]  DeviceAddress     The base of device memory address to be used as the DMA memory.
+  @param[in]  HostAddress       The base of host memory address to be used as the DMA memory.
+  @param[in]  Length            The length of device memory address to be used as the DMA memory.
+
+  @retval EFI_SUCCESS            The HostAddress is remmapped for the memory range specified by DeviceAddress and Length.
+  @retval EFI_INVALID_PARAMETER  DeviceHandle is not NULL, and it is an invalid handle.
+  @retval EFI_INVALID_PARAMETER  DeviceAddress is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  HostAddress is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  Length is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  Length is 0.
+  @retval EFI_UNSUPPORTED        DeviceHandle is unknown by the IOMMU.
+  @retval EFI_UNSUPPORTED        The remap function is unsupported by the IOMMU.
+  @retval EFI_UNSUPPORTED        The IOMMU does not support the memory range specified by DeviceAddress and Length.
+  @retval EFI_OUT_OF_RESOURCES   There are not enough resources available to modify the IOMMU attribute.
+  @retval EFI_DEVICE_ERROR       The IOMMU device reported an error while attempting the operation.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EDKII_IOMMU_SET_REMAP_ADDRESS)(
+  IN EDKII_IOMMU_PROTOCOL  *This,
+  IN EFI_HANDLE            DeviceHandle, OPTIONAL
+  IN EFI_PHYSICAL_ADDRESS  DeviceAddress,
+  IN VOID                  *HostAddress,
+  IN UINT64                Length
+  );
+
+/**
+  Return a remapped host address from a device address.
+
+  @param[in]  This              The protocol instance pointer.
+  @param[in]  DeviceHandle      The device who initiates the DMA access request.
+  @param[in]  DeviceAddress     The base of device memory address to be used as the DMA memory.
+  @param[out] HostAddress       The base of host memory address to be used as the DMA memory.
+
+  @retval EFI_SUCCESS            The HostAddress remmapped for the memory range specified by DeviceAddress is returned.
+  @retval EFI_INVALID_PARAMETER  DeviceHandle is not NULL, and it is an invalid handle.
+  @retval EFI_INVALID_PARAMETER  DeviceAddress is not IoMmu Page size aligned.
+  @retval EFI_INVALID_PARAMETER  HostAddress is NULL.
+  @retval EFI_UNSUPPORTED        DeviceHandle is unknown by the IOMMU.
+  @retval EFI_UNSUPPORTED        The remap function is unsupported by the IOMMU.
+  @retval EFI_NOT_FOUND          The HostAddress for DeviceAddress is not found.
+  @retval EFI_DEVICE_ERROR       The IOMMU device reported an error while attempting the operation.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EDKII_IOMMU_GET_REMAP_ADDRESS)(
+  IN EDKII_IOMMU_PROTOCOL  *This,
+  IN EFI_HANDLE            DeviceHandle, OPTIONAL
+  IN EFI_PHYSICAL_ADDRESS  DeviceAddress,
+  OUT VOID                 **HostAddress
+  );
+
+///
+/// IOMMU Protocol structure.
+///
+struct _EDKII_IOMMU_PROTOCOL {
+  UINT64                              Revision;
+  EDKII_IOMMU_GET_PAGE_SIZE           GetPageSize;
+  EDKII_IOMMU_SET_ATTRIBUTE           SetAttribute;
+  EDKII_IOMMU_SET_REMAP_ADDRESS       SetRemapAddress;
+  EDKII_IOMMU_GET_REMAP_ADDRESS       GetRemapAddress;
+};
+
+///
+/// IOMMU Protocol GUID variable.
+///
+extern EFI_GUID gEdkiiIoMmuProtocolGuid;
+
+#endif
diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 356b3e1..db596b6 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -540,6 +540,9 @@
   ## Include/Protocol/NonDiscoverableDevice.h
   gEdkiiNonDiscoverableDeviceProtocolGuid = { 0x0d51905b, 0xb77e, 0x452a, {0xa2, 0xc0, 0xec, 0xa0, 0xcc, 0x8d, 0x51, 0x4a } }
 
+  ## Include/Protocol/IoMmu.h
+  gEdkiiIoMmuProtocolGuid = { 0x4e939de9, 0xd948, 0x4b0f, { 0x88, 0xed, 0xe6, 0xe1, 0xce, 0x51, 0x7c, 0x1e } }
+
 #
 # [Error.gEfiMdeModulePkgTokenSpaceGuid]
 #   0x80000001 | Invalid value provided.
-- 
2.7.4.windows.1