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author | Laszlo Ersek <lersek@redhat.com> | 2015-11-30 18:41:33 +0000 |
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committer | lersek <lersek@Edk2> | 2015-11-30 18:41:33 +0000 |
commit | b09c1c6f2569a2c1e927f3b53cb3082294226295 (patch) | |
tree | c6b54a28c584faef2e0d314a4169aa2b444da220 /OvmfPkg/OvmfPkgX64.fdf | |
parent | cdef34ec12f91023fa86bb49d1f33541d87eb132 (diff) | |
download | edk2-b09c1c6f2569a2c1e927f3b53cb3082294226295.tar.gz edk2-b09c1c6f2569a2c1e927f3b53cb3082294226295.tar.bz2 edk2-b09c1c6f2569a2c1e927f3b53cb3082294226295.zip |
OvmfPkg: PlatformPei: account for TSEG size with PcdSmmSmramRequire set
PlatformPei calls GetSystemMemorySizeBelow4gb() in three locations:
- PublishPeiMemory(): on normal boot, the permanent PEI RAM is installed
so that it ends with the RAM below 4GB,
- QemuInitializeRam(): on normal boot, memory resource descriptor HOBs are
created for the RAM below 4GB; plus MTRR attributes are set
(independently of S3 vs. normal boot)
- MemMapInitialization(): an MMIO resource descriptor HOB is created for
PCI resource allocation, on normal boot, starting at max(RAM below 4GB,
2GB).
The first two of these is adjusted for the configured TSEG size, if
PcdSmmSmramRequire is set:
- In PublishPeiMemory(), the permanent PEI RAM is kept under TSEG.
- In QemuInitializeRam(), we must keep the DXE out of TSEG.
One idea would be to simply trim the [1MB .. LowerMemorySize] memory
resource descriptor HOB, leaving a hole for TSEG in the memory space
map.
The SMM IPL will however want to massage the caching attributes of the
SMRAM range that it loads the SMM core into, with
gDS->SetMemorySpaceAttributes(), and that won't work on a hole. So,
instead of trimming this range, split the TSEG area off, and report it
as a cacheable reserved memory resource.
Finally, since reserved memory can be allocated too, pre-allocate TSEG
in InitializeRamRegions(), after QemuInitializeRam() returns. (Note that
this step alone does not suffice without the resource descriptor HOB
trickery: if we omit that, then the DXE IPL PEIM fails to load and start
the DXE core.)
- In MemMapInitialization(), the start of the PCI MMIO range is not
affected.
We choose the largest option (8MB) for the default TSEG size. Michael
Kinney pointed out that the SMBASE relocation in PiSmmCpuDxeSmm consumes
SMRAM proportionally to the number of CPUs. From the three options
available, he reported that 8MB was both necessary and sufficient for the
SMBASE relocation to succeed with 255 CPUs:
- http://thread.gmane.org/gmane.comp.bios.edk2.devel/3020/focus=3137
- http://thread.gmane.org/gmane.comp.bios.edk2.devel/3020/focus=3177
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19039 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'OvmfPkg/OvmfPkgX64.fdf')
0 files changed, 0 insertions, 0 deletions