[PATCH v2 3/7] 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 | 51 +++++++++++++++++++-
 3 files changed, 52 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..c8b861093292 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
@@ -96,6 +96,7 @@
   gEfiIncompatiblePciDeviceSupportProtocolGuid    ## SOMETIMES_CONSUMES
   gEfiLoadFile2ProtocolGuid                       ## SOMETIMES_PRODUCES
   gEdkiiIoMmuProtocolGuid                         ## SOMETIMES_CONSUMES
+  gEdkiiPeCoffImageEmulatorProtocolGuid           ## SOMETIMES_CONSUMES
   gEfiLoadedImageDevicePathProtocolGuid           ## CONSUMES
 
 [FeaturePcd]
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
index c2be85a906af..ac3a9fcaf1d0 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
@@ -651,6 +651,54 @@ RomDecode (
   }
 }
 
+STATIC
+BOOLEAN
+IsImageTypeSupported (
+  IN  UINT16    MachineType,
+  IN  UINT16    SubSystem
+  )
+{
+  EFI_STATUS                            Status;
+  EDKII_PECOFF_IMAGE_EMULATOR_PROTOCOL  *Emu;
+  UINTN                                 HandleCount;
+  EFI_HANDLE                            *HandleBuffer;
+  BOOLEAN                               ReturnValue;
+  UINTN                                 Index;
+
+  if (EFI_IMAGE_MACHINE_TYPE_SUPPORTED (MachineType)) {
+    return TRUE;
+  }
+
+  Status = gBS->LocateHandleBuffer (
+                  ByProtocol,
+                  &gEdkiiPeCoffImageEmulatorProtocolGuid,
+                  NULL,
+                  &HandleCount,
+                  &HandleBuffer
+                  );
+  if (EFI_ERROR (Status)) {
+    return FALSE;
+  }
+
+  ReturnValue = FALSE;
+  for (Index = 0; Index < HandleCount; Index++) {
+    Status = gBS->HandleProtocol (
+                    HandleBuffer[Index],
+                    &gEdkiiPeCoffImageEmulatorProtocolGuid,
+                    (VOID **)&Emu
+                    );
+    ASSERT_EFI_ERROR (Status);
+
+    if (Emu->IsImageSupported (Emu, MachineType, SubSystem)) {
+      ReturnValue = TRUE;
+      break;
+    }
+  }
+
+  FreePool (HandleBuffer);
+  return ReturnValue;
+}
+
 /**
   Load and start the Option Rom image.
 
@@ -715,7 +763,8 @@ ProcessOpRomImage (
     //
     // Skip the EFI PCI Option ROM image if its machine type is not supported
     //
-    if (!EFI_IMAGE_MACHINE_TYPE_SUPPORTED (EfiRomHeader->EfiMachineType)) {
+    if (!IsImageTypeSupported(EfiRomHeader->EfiMachineType,
+                              EfiRomHeader->EfiSubsystem)) {
       goto NextImage;
     }
 
-- 
2.17.1