UefiCpuPkg/MtrrLib: Don't report OutOfResource when MTRR is enough
authorRuiyu Ni <ruiyu.ni@intel.com>
Fri, 5 May 2017 02:10:00 +0000 (10:10 +0800)
committerRuiyu Ni <ruiyu.ni@intel.com>
Mon, 8 May 2017 05:35:25 +0000 (13:35 +0800)
commit3654c4623c9b37ddc64426995fa399d8626b7ced
treeb7a9470dd26da2e79dd177fea90c4179b80d2812
parent007b51e180d2202637dfc6d2afbe8a34704c423f
UefiCpuPkg/MtrrLib: Don't report OutOfResource when MTRR is enough

The MTRR calculation algorithm contains a bug that when left
subtraction cannot produce better MTRR solution, it forgets
to restore the BaseAddress/Length so that MtrrLibGetMtrrNumber()
returns bigger value of actual required MTRR numbers.
As a result, the MtrrLib reports OutOfResource but actually the
MTRR is enough.

MEMORY_RANGE mC[] = {
  0, 0x100000, CacheUncacheable,
  0x100000, 0x89F00000, CacheWriteBack,
  0x8A000000, 0x75000000, CacheUncacheable,
  0xFF000000, 0x01000000, CacheWriteProtected,
  0x100000000, 0x7F00000000, CacheUncacheable,
  0xFC240000, 0x2000, CacheWriteCombining // <-- trigger the error
};

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
UefiCpuPkg/Library/MtrrLib/MtrrLib.c