ArmVirtualizationPkg/PciHostBridgeDxe: skip 0 AddrLen in SubmitResources()

According to Volume 5 of the PI spec, 10.8.2 PCI Host Bridge Resource
Allocation Protocol, SubmitResources(),

  It is considered an error if no resource requests are submitted for a
  PCI root bridge. If a PCI root bridge does not require any resources, a
  zero-length resource request must explicitly be submitted.

Under MdeModulePkg/Bus/Pci/PciBusDxe/, we have:

  PciHostBridgeResourceAllocator()                   [PciLib.c]
    ConstructAcpiResourceRequestor(..., &AcpiConfig) [PciEnumerator.c]
    PciResAlloc->SubmitResources(..., &AcpiConfig)
    ASSERT_EFI_ERROR ()

If ConstructAcpiResourceRequestor() finds no resources to request (for
example because no PCI devices are on the root bridge), it places a
zero-length EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR followed by an
EFI_ACPI_END_TAG_DESCRIPTOR in "AcpiConfig"; satisfying the PI spec.

However, PciHostBridgeDxe's SubmitResources() function does not expect
such input; the following part of the code rejects it:

        switch (Ptr->ResType) {

        case 0:

          //
          // Check invalid Address Sapce Granularity
          //
          if (Ptr->AddrSpaceGranularity != 32) {
            return EFI_INVALID_PARAMETER;
          }

Skip EFI_ACPI_ADDRESS_SPACE_DESCRIPTORs with zero AddrLen early. Also,
allow PciHostBridgeResourceAllocator() to proceed to the AllocateResources
phase by setting "ResourceSubmited" to TRUE.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Olivier Martin <Olivier.martin@arm.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16907 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 8 insertions, 3 deletions

diff --git a/ArmPlatformPkg/ArmVirtualizationPkg/PciHostBridgeDxe/PciHostBridge.c b/ArmPlatformPkg/ArmVirtualizationPkg/PciHostBridgeDxe/PciHostBridge.c
index 1534c3dc04..bf78ded541 100644
--- a/ArmPlatformPkg/ArmVirtualizationPkg/PciHostBridgeDxe/PciHostBridge.c
+++ b/ArmPlatformPkg/ArmVirtualizationPkg/PciHostBridgeDxe/PciHostBridge.c
@@ -929,12 +929,19 @@ SubmitResources(
   while (List != &HostBridgeInstance->Head) {

     RootBridgeInstance = DRIVER_INSTANCE_FROM_LIST_ENTRY (List);

     if (RootBridgeHandle == RootBridgeInstance->Handle) {

-      while ( *Temp == 0x8A) {

+      for (;

+           *Temp == 0x8A;

+           Temp += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR)

+           ) {

         Ptr = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Temp ;

 

         //

         // Check Address Length

         //

+        if (Ptr->AddrLen == 0) {

+          HostBridgeInstance->ResourceSubmited = TRUE;

+          continue;

+        }

         if (Ptr->AddrLen > 0xffffffff) {

           return EFI_INVALID_PARAMETER;

         }

@@ -1002,8 +1009,6 @@ SubmitResources(
         default:

             break;

         };

-    

-        Temp += sizeof (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR) ;

       } 

       

       return EFI_SUCCESS;