[RFC] [PATCH V4 3/3] MdeModulePkg/PciBus: Add IOMMU support.

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

If IOMMU protocol is installed, PciBus need call IOMMU
to set access attribute for the PCI device in Map/Ummap.

Only after the access attribute is set, the PCI device can
access the DMA memory.

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/Bus/Pci/PciBusDxe/PciBus.c      |  9 +++++
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h      |  1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf |  1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciIo.c       | 37 ++++++++++++++++++++
 4 files changed, 48 insertions(+)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.c
index f3be47a..950cacc 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.c
@@ -42,6 +42,7 @@ UINT64                                        gAllZero             = 0;
 
 EFI_PCI_PLATFORM_PROTOCOL                     *gPciPlatformProtocol;
 EFI_PCI_OVERRIDE_PROTOCOL                     *gPciOverrideProtocol;
+EDKII_IOMMU_PROTOCOL                          *mIoMmuProtocol;
 
 
 GLOBAL_REMOVE_IF_UNREFERENCED EFI_PCI_HOTPLUG_REQUEST_PROTOCOL mPciHotPlugRequest = {
@@ -284,6 +285,14 @@ PciBusDriverBindingStart (
           );
   }  
 
+  if (mIoMmuProtocol == NULL) {
+    gBS->LocateProtocol (
+          &gEdkiiIoMmuProtocolGuid,
+          NULL,
+          (VOID **) &mIoMmuProtocol
+          );
+  }
+
   if (PcdGetBool (PcdPciDisableBusEnumeration)) {
     gFullEnumeration = FALSE;
   } else {
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
index 39ba8b9..3bcc134 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
@@ -32,6 +32,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Protocol/IncompatiblePciDeviceSupport.h>
 #include <Protocol/PciOverride.h>
 #include <Protocol/PciEnumerationComplete.h>
+#include <Protocol/IoMmu.h>
 
 #include <Library/DebugLib.h>
 #include <Library/UefiDriverEntryPoint.h>
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
index a3ab11f..5da094f 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
@@ -95,6 +95,7 @@
   gEfiPciRootBridgeIoProtocolGuid                 ## TO_START
   gEfiIncompatiblePciDeviceSupportProtocolGuid    ## SOMETIMES_CONSUMES
   gEfiLoadFile2ProtocolGuid                       ## SOMETIMES_PRODUCES
+  gEdkiiIoMmuProtocolGuid                         ## SOMETIMES_CONSUMES
 
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdPciBusHotplugDeviceSupport      ## CONSUMES
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciIo.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciIo.c
index f72598d..c0251c0 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciIo.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciIo.c
@@ -14,6 +14,8 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
 #include "PciBus.h"
 
+extern EDKII_IOMMU_PROTOCOL                          *mIoMmuProtocol;
+
 //
 // Pci Io Protocol Interface
 //
@@ -967,6 +969,7 @@ PciIoMap (
 {
   EFI_STATUS    Status;
   PCI_IO_DEVICE *PciIoDevice;
+  UINT64        IoMmuAttribute;
 
   PciIoDevice = PCI_IO_DEVICE_FROM_PCI_IO_THIS (This);
 
@@ -999,6 +1002,31 @@ PciIoMap (
       );
   }
 
+  if (mIoMmuProtocol != NULL) {
+    if (!EFI_ERROR (Status)) {
+      switch (Operation) {
+      case EfiPciIoOperationBusMasterRead:
+        IoMmuAttribute = EDKII_IOMMU_ACCESS_READ;
+        break;
+      case EfiPciIoOperationBusMasterWrite:
+        IoMmuAttribute = EDKII_IOMMU_ACCESS_WRITE;
+        break;
+      case EfiPciIoOperationBusMasterCommonBuffer:
+        IoMmuAttribute = EDKII_IOMMU_ACCESS_READ | EDKII_IOMMU_ACCESS_WRITE;
+        break;
+      default:
+        ASSERT(FALSE);
+        return EFI_INVALID_PARAMETER;
+      }
+      mIoMmuProtocol->SetMappingAttribute (
+                        mIoMmuProtocol,
+                        PciIoDevice->Handle,
+                        *Mapping,
+                        IoMmuAttribute
+                        );
+    }
+  }
+
   return Status;
 }
 
@@ -1024,6 +1052,15 @@ PciIoUnmap (
 
   PciIoDevice = PCI_IO_DEVICE_FROM_PCI_IO_THIS (This);
 
+  if (mIoMmuProtocol != NULL) {
+    mIoMmuProtocol->SetMappingAttribute (
+                      mIoMmuProtocol,
+                      PciIoDevice->Handle,
+                      Mapping,
+                      0
+                      );
+  }
+
   Status = PciIoDevice->PciRootBridgeIo->Unmap (
                                           PciIoDevice->PciRootBridgeIo,
                                           Mapping
-- 
2.7.4.windows.1