OvmfPkg: PlatformPei: enable PCIEXBAR (aka MMCONFIG / ECAM) on Q35

[mirror_edk2.git] / OvmfPkg / OvmfPkgIa32.dsc

diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc
index 9b603f001fe5b25394e07481bb83d48eb4f7dedf..aae1972950ee5f2cd1e1f43ab3b3d6b3c6679932 100644 (file)
--- a/OvmfPkg/OvmfPkgIa32.dsc
+++ b/OvmfPkg/OvmfPkgIa32.dsc
@@ -395,6 +395,14 @@
   gEfiMdePkgTokenSpaceGuid.PcdDebugPropertyMask|0x2F\r
 !endif\r
 \r
+  # This PCD is used to set the base address of the PCI express hierarchy. It\r
+  # is only consulted when OVMF runs on Q35. In that case it is programmed into\r
+  # the PCIEXBAR register.\r
+  #\r
+  # On Q35 machine types that QEMU intends to support in the long term, QEMU\r
+  # never lets the RAM below 4 GB exceed 2 GB.\r
+  gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0x80000000\r
+\r
 !ifdef $(SOURCE_DEBUG_ENABLE)\r
   gEfiSourceLevelDebugPkgTokenSpaceGuid.PcdDebugLoadImageMethod|0x2\r
 !endif\r