diff options
| -rw-r--r-- | MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c index ccec37b287..7dfa933918 100644 --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c @@ -1,7 +1,7 @@ /** @file
PCI emumeration support functions implementation for PCI Bus module.
-Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -459,6 +459,9 @@ GatherPpbInfo ( UINT8 Value;
EFI_PCI_IO_PROTOCOL *PciIo;
UINT8 Temp;
+ UINT32 PMemBaseLimit;
+ UINT16 PrefetchableMemoryBase;
+ UINT16 PrefetchableMemoryLimit;
PciIoDevice = CreatePciIoDevice (
Bridge,
@@ -552,14 +555,22 @@ GatherPpbInfo ( PciIoDevice,
0x24,
NULL,
- NULL
+ &PMemBaseLimit
);
//
// Test if it supports 64 memory or not
//
- if (!EFI_ERROR (Status)) {
-
+ // The bottom 4 bits of both the Prefetchable Memory Base and Prefetchable Memory Limit
+ // registers:
+ // 0 - the bridge supports only 32 bit addresses.
+ // 1 - the bridge supports 64-bit addresses.
+ //
+ PrefetchableMemoryBase = PMemBaseLimit & 0xffff;
+ PrefetchableMemoryLimit = PMemBaseLimit >> 16;
+ if (!EFI_ERROR (Status) &&
+ (PrefetchableMemoryBase & 0x000f) == 0x0001 &&
+ (PrefetchableMemoryLimit & 0x000f) == 0x0001) {
Status = BarExisted (
PciIoDevice,
0x28,
|