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| author | Laszlo Ersek <lersek@redhat.com> | 2019-05-29 11:59:02 +0200 |
|---|---|---|
| committer | Laszlo Ersek <lersek@redhat.com> | 2019-06-03 19:54:34 +0200 |
| commit | b07de0974b65a6a393c2d477427d1d6c7acce002 (patch) | |
| tree | a172afc620bccebde3fe9bac57825b7f660bb4c9 | |
| parent | d4534984111328ff839fbf51be2779a98bfefa30 (diff) | |
| download | edk2-b07de0974b65a6a393c2d477427d1d6c7acce002.tar.gz edk2-b07de0974b65a6a393c2d477427d1d6c7acce002.tar.bz2 edk2-b07de0974b65a6a393c2d477427d1d6c7acce002.zip | |
OvmfPkg: raise the PCIEXBAR base to 2816 MB on Q35
(This is a replacement for commit 75136b29541b, "OvmfPkg/PlatformPei:
reorder the 32-bit PCI window vs. the PCIEXBAR on q35", 2019-05-16).
Commit 7b8fe63561b4 ("OvmfPkg: PlatformPei: enable PCIEXBAR (aka MMCONFIG
/ ECAM) on Q35", 2016-03-10) claimed that,
On Q35 machine types that QEMU intends to support in the long term, QEMU
never lets the RAM below 4 GB exceed 2 GB.
Alas, this statement came from a misunderstanding that occurred while we
worked out the interface contract. In fact QEMU does allow the 32-bit RAM
extend up to 0xB000_0000 (exclusive), in case the RAM size falls in the
range (0x8000_0000, 0xB000_0000) (i.e., the RAM size is greater than
2048MB and smaller than 2816MB).
In turn, such a RAM size (justifiedly) triggers
ASSERT (TopOfLowRam <= PciExBarBase);
in MemMapInitialization(), because we placed the 256MB PCIEXBAR at
0x8000_0000 (2GB) exactly, relying on the interface contract. (And, the
32-bit PCI window would follow the PCIEXBAR, covering the [0x9000_0000,
0xFC00_0000) range.)
In order to fix this, place the PCIEXBAR at 2816MB (0xB000_0000), and
start the 32-bit PCI window at 3 GB (0xC000_0000). This shrinks the 32-bit
PCI window to
0xFC00_0000 - 0xC000_0000 = 0x3C00_0000 = 960 MB.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1859
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
| -rw-r--r-- | OvmfPkg/OvmfPkgIa32.dsc | 4 | ||||
| -rw-r--r-- | OvmfPkg/OvmfPkgIa32X64.dsc | 4 | ||||
| -rw-r--r-- | OvmfPkg/OvmfPkgX64.dsc | 4 |
3 files changed, 6 insertions, 6 deletions
diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc index 578fc6c98e..e74a9d5a51 100644 --- a/OvmfPkg/OvmfPkgIa32.dsc +++ b/OvmfPkg/OvmfPkgIa32.dsc @@ -492,8 +492,8 @@ # the PCIEXBAR register.
#
# On Q35 machine types that QEMU intends to support in the long term, QEMU
- # never lets the RAM below 4 GB exceed 2 GB.
- gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0x80000000
+ # never lets the RAM below 4 GB exceed 2816 MB.
+ gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0xB0000000
!ifdef $(SOURCE_DEBUG_ENABLE)
gEfiSourceLevelDebugPkgTokenSpaceGuid.PcdDebugLoadImageMethod|0x2
diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc index eade8f62d3..67ac015991 100644 --- a/OvmfPkg/OvmfPkgIa32X64.dsc +++ b/OvmfPkg/OvmfPkgIa32X64.dsc @@ -497,8 +497,8 @@ # the PCIEXBAR register.
#
# On Q35 machine types that QEMU intends to support in the long term, QEMU
- # never lets the RAM below 4 GB exceed 2 GB.
- gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0x80000000
+ # never lets the RAM below 4 GB exceed 2816 MB.
+ gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0xB0000000
!ifdef $(SOURCE_DEBUG_ENABLE)
gEfiSourceLevelDebugPkgTokenSpaceGuid.PcdDebugLoadImageMethod|0x2
diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc index 733a4c9d8a..68073ef55b 100644 --- a/OvmfPkg/OvmfPkgX64.dsc +++ b/OvmfPkg/OvmfPkgX64.dsc @@ -497,8 +497,8 @@ # the PCIEXBAR register.
#
# On Q35 machine types that QEMU intends to support in the long term, QEMU
- # never lets the RAM below 4 GB exceed 2 GB.
- gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0x80000000
+ # never lets the RAM below 4 GB exceed 2816 MB.
+ gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0xB0000000
!ifdef $(SOURCE_DEBUG_ENABLE)
gEfiSourceLevelDebugPkgTokenSpaceGuid.PcdDebugLoadImageMethod|0x2
|