Update resource degrade algorithm in PCI bus driver. (1)If any child device has both option ROM and 64-bit BAR, degrade its PMEM64/MEM64 requests in case that if a legacy option ROM image can not access 64-bit resources. (2) If there are both PMEM64 and PMEM32 requests from child devices, which can not be satisfied by a P2P bridge simultaneously, keep PMEM64 and degrade PMEM32 to MEM32. (3) PMEM64/MEM64 are not supported when firmware is in 32-bit mode.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9599 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 70 insertions, 29 deletions

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumerator.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumerator.c
index ece3ee830f..aa209cd8cf 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumerator.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumerator.c
@@ -475,6 +475,7 @@ DetermineRootBridgeAttributes (
   }

 

   if ((Attributes & EFI_PCI_HOST_BRIDGE_MEM64_DECODE) != 0) {

+    RootBridgeDev->Decodes |= EFI_BRIDGE_MEM64_DECODE_SUPPORTED;

     RootBridgeDev->Decodes |= EFI_BRIDGE_PMEM64_DECODE_SUPPORTED;

   }

 

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
index 7fd856e5ca..d6291b9375 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciResourceSupport.c
@@ -1047,31 +1047,59 @@ DegradeResource (
   IN PCI_RESOURCE_NODE *PMem64Node

   )

 {

-  BOOLEAN              HasOprom;

   PCI_IO_DEVICE        *Temp;

   LIST_ENTRY           *CurrentLink;

+  PCI_RESOURCE_NODE    *TempNode;

 

   //

-  // For RootBridge, PPB , P2C, go recursively to traverse all its children

-  // to find if this bridge and downstream has OptionRom.

+  // If any child device has both option ROM and 64-bit BAR, degrade its PMEM64/MEM64

+  // requests in case that if a legacy option ROM image can not access 64-bit resources.

   //

-  HasOprom = FALSE;

   CurrentLink = Bridge->ChildList.ForwardLink;

   while (CurrentLink != NULL && CurrentLink != &Bridge->ChildList) {

-

     Temp = PCI_IO_DEVICE_FROM_LINK (CurrentLink);

     if (Temp->RomSize != 0) {

-      HasOprom = TRUE;

-      break;

+      if (!IsListEmpty (&Mem64Node->ChildList)) {      

+        CurrentLink = Mem64Node->ChildList.ForwardLink;

+        while (CurrentLink != &Mem64Node->ChildList) {

+          TempNode = RESOURCE_NODE_FROM_LINK (CurrentLink);

+

+          if (TempNode->PciDev == Temp) {

+            RemoveEntryList (CurrentLink);

+            InsertResourceNode (Mem32Node, TempNode);

+          }

+          CurrentLink = TempNode->Link.ForwardLink;

+        }        

+      }

+

+      if (!IsListEmpty (&PMem64Node->ChildList)) {      

+        CurrentLink = PMem64Node->ChildList.ForwardLink;

+        while (CurrentLink != &PMem64Node->ChildList) {

+          TempNode = RESOURCE_NODE_FROM_LINK (CurrentLink);

+

+          if (TempNode->PciDev == Temp) {

+            RemoveEntryList (CurrentLink);

+            InsertResourceNode (PMem32Node, TempNode);

+          }

+          CurrentLink = TempNode->Link.ForwardLink;

+        }        

+      }

+

     }

     CurrentLink = CurrentLink->ForwardLink;

   }

 

   //

-  // If bridge doesn't support Prefetchable

-  // memory64, degrade it to Prefetchable memory32

+  // If firmware is in 32-bit mode,

+  // then degrade PMEM64/MEM64 requests

   //

-  if (!BridgeSupportResourceDecode (Bridge, EFI_BRIDGE_PMEM64_DECODE_SUPPORTED)) {

+  if (sizeof (UINTN) <= 4) {

+    MergeResourceTree (

+      Mem32Node,

+      Mem64Node,

+      TRUE

+      );

+

     MergeResourceTree (

       PMem32Node,

       PMem64Node,

@@ -1079,31 +1107,38 @@ DegradeResource (
       );

   } else {

     //

-    // if no PMem32 request and no OptionRom request, still keep PMem64. Otherwise degrade to PMem32

+    // if the bridge does not support MEM64, degrade MEM64 to MEM32

     //

-    if ((PMem32Node != NULL && (PMem32Node->Length != 0 && Bridge->Parent != NULL)) || HasOprom) {

-      //

-      // Fixed the issue that there is no resource for 64-bit (above 4G)

-      //

+    if (!BridgeSupportResourceDecode (Bridge, EFI_BRIDGE_MEM64_DECODE_SUPPORTED)) {

+        MergeResourceTree (

+          Mem32Node,

+          Mem64Node,

+          TRUE

+          );

+    }

+

+    //

+    // if the bridge does not support PMEM64, degrade PMEM64 to PMEM32

+    //

+    if (!BridgeSupportResourceDecode (Bridge, EFI_BRIDGE_PMEM64_DECODE_SUPPORTED)) {

       MergeResourceTree (

         PMem32Node,

         PMem64Node,

         TRUE

         );

-    }

-  }

+    } 

 

-

-  //

-  // If bridge doesn't support Mem64

-  // degrade it to mem32

-  //

-  if (!BridgeSupportResourceDecode (Bridge, EFI_BRIDGE_MEM64_DECODE_SUPPORTED)) {

-    MergeResourceTree (

-      Mem32Node,

-      Mem64Node,

-      TRUE

-      );

+    //

+    // if both PMEM64 and PMEM32 requests from child devices, which can not be satisfied

+    // by a P2P bridge simultaneously, keep PMEM64 and degrade PMEM32 to MEM32.

+    //

+    if (!IsListEmpty (&PMem64Node->ChildList) && Bridge->Parent != NULL) {

+      MergeResourceTree (

+        Mem32Node,

+        PMem32Node,

+        TRUE

+        );

+    }

   }

 

   //

@@ -1119,7 +1154,7 @@ DegradeResource (
   }

 

   //

-  // if bridge supports combined Pmem Mem decoding

+  // if root bridge supports combined Pmem Mem decoding

   // merge these two type of resource

   //

   if (BridgeSupportResourceDecode (Bridge, EFI_BRIDGE_PMEM_MEM_COMBINE_SUPPORTED)) {

@@ -1129,6 +1164,11 @@ DegradeResource (
       FALSE

       );

 

+    //

+    // No need to check if to degrade MEM64 after merge, because

+    // if there are PMEM64 still here, 64-bit decode should be supported

+    // by the root bride.

+    //

     MergeResourceTree (

       Mem64Node,

       PMem64Node,