[PATCH 3/4] MdeModulePkg/PciBusDxe: invoke PE/COFF emulator for foreign option ROMs

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

When enumerating option ROM images, take into account whether an emulator
exists that would allow dispatch of PE/COFF images built for foreign
architectures.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h              |  1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf         |  1 +
 MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c | 16 +++++++++++++++-
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
index 55eb3a5a8070..dc57d4876c0f 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h
@@ -33,6 +33,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Protocol/PciOverride.h>
 #include <Protocol/PciEnumerationComplete.h>
 #include <Protocol/IoMmu.h>
+#include <Protocol/PeCoffImageEmulator.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 a21dd2b5edf4..3d99ea0c1047 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
@@ -97,6 +97,7 @@
   gEfiLoadFile2ProtocolGuid                       ## SOMETIMES_PRODUCES
   gEdkiiIoMmuProtocolGuid                         ## SOMETIMES_CONSUMES
   gEfiLoadedImageDevicePathProtocolGuid           ## CONSUMES
+  gEdkiiPeCoffImageEmulatorProtocolGuid           ## SOMETIMES_CONSUMES
 
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdPciBusHotplugDeviceSupport      ## CONSUMES
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
index c2be85a906af..07236afd327d 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
@@ -678,6 +678,7 @@ ProcessOpRomImage (
   MEDIA_RELATIVE_OFFSET_RANGE_DEVICE_PATH  EfiOpRomImageNode;
   VOID                                     *Buffer;
   UINTN                                    BufferSize;
+  EDKII_PECOFF_IMAGE_EMULATOR_PROTOCOL     *PeCoffEmulator;
 
   Indicator = 0;
 
@@ -693,6 +694,7 @@ ProcessOpRomImage (
   }
   ASSERT (((EFI_PCI_EXPANSION_ROM_HEADER *) RomBarOffset)->Signature == PCI_EXPANSION_ROM_HEADER_SIGNATURE);
 
+  PeCoffEmulator = NULL;
   do {
     EfiRomHeader = (EFI_PCI_EXPANSION_ROM_HEADER *) RomBarOffset;
     if (EfiRomHeader->Signature != PCI_EXPANSION_ROM_HEADER_SIGNATURE) {
@@ -716,7 +718,19 @@ ProcessOpRomImage (
     // Skip the EFI PCI Option ROM image if its machine type is not supported
     //
     if (!EFI_IMAGE_MACHINE_TYPE_SUPPORTED (EfiRomHeader->EfiMachineType)) {
-      goto NextImage;
+      //
+      // Check whether we have a PE/COFF emulator that supports this image
+      //
+      if (PeCoffEmulator == NULL) {
+        gBS->LocateProtocol (&gEdkiiPeCoffImageEmulatorProtocolGuid, NULL,
+               (VOID **)&PeCoffEmulator);
+      }
+      if (PeCoffEmulator == NULL ||
+          !PeCoffEmulator->IsImageSupported (PeCoffEmulator,
+                             EfiRomHeader->EfiMachineType,
+                             EfiRomHeader->EfiSubsystem)) {
+        goto NextImage;
+      }
     }
 
     //
-- 
2.17.1