diff options
| author | Jeff Fan <jeff.fan@intel.com> | 2016-04-21 10:28:17 +0800 |
|---|---|---|
| committer | Jeff Fan <jeff.fan@intel.com> | 2016-04-29 10:07:07 +0800 |
| commit | 07e889209034ba94bfac9e765b8a50ef344daef2 (patch) | |
| tree | 9de5e2542263f52df58a06d53efbacfb320f70d5 /UefiCpuPkg/Library | |
| parent | aaa1e579a5109a868863c8a3c7a51580f83b4c38 (diff) | |
| download | edk2-platforms-07e889209034ba94bfac9e765b8a50ef344daef2.tar.xz | |
UefiCpuPkg/MtrrLib: Remove the loop of calculating Fixed-MTRR Mask
Introduce the 32bit mask seeds to calculate Fixed-MTRR or&and mask values. It
could avoid the loop operation and 64bit shift operations.
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
Diffstat (limited to 'UefiCpuPkg/Library')
| -rw-r--r-- | UefiCpuPkg/Library/MtrrLib/MtrrLib.c | 39 |
1 files changed, 23 insertions, 16 deletions
diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index 06a361bd84..c4a39b554d 100644 --- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c +++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c @@ -20,6 +20,9 @@ #include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
+#define OR_SEED 0x01010101
+#define CLEAR_SEED 0xFFFFFFFF
+
//
// Context to save and restore when MTRRs are programmed
//
@@ -460,11 +463,12 @@ ProgramFixedMtrr ( {
UINT32 MsrNum;
UINT32 ByteShift;
- UINT64 OrMask;
- UINT64 ClearMask;
+ UINT32 OrMask[2];
+ UINT32 ClearMask[2];
+ UINT64 SubLength;
- OrMask = 0;
- ClearMask = 0;
+ *(UINT64 *)OrMask = 0;
+ *(UINT64 *)ClearMask = 0;
for (MsrNum = *LastMsrNum + 1; MsrNum < MTRR_NUMBER_OF_FIXED_MTRR; MsrNum++) {
if ((*Base >= mMtrrLibFixedMtrrTable[MsrNum].BaseAddress) &&
@@ -493,24 +497,27 @@ ProgramFixedMtrr ( return RETURN_UNSUPPORTED;
}
- for (
- ;
- ((ByteShift < 8) && (*Length >= mMtrrLibFixedMtrrTable[MsrNum].Length));
- ByteShift++
- ) {
- OrMask |= LShiftU64 ((UINT64) MemoryCacheType, (UINT32) (ByteShift * 8));
- ClearMask |= LShiftU64 ((UINT64) 0xFF, (UINT32) (ByteShift * 8));
- *Length -= mMtrrLibFixedMtrrTable[MsrNum].Length;
- *Base += mMtrrLibFixedMtrrTable[MsrNum].Length;
+ if (ByteShift < 4) {
+ OrMask[0] = OR_SEED * (UINT32)MemoryCacheType;
+ ClearMask[0] = CLEAR_SEED;
+ OrMask[1] = (OR_SEED * (UINT32)MemoryCacheType) >> ((4 - ByteShift) * 8);
+ ClearMask[1] = CLEAR_SEED >> ((4 - ByteShift) * 8);
+ } else {
+ OrMask[0] = (OR_SEED * (UINT32)MemoryCacheType) >> ((8 - ByteShift) * 8);
+ ClearMask[0] = CLEAR_SEED >> ((8 - ByteShift) * 8);
}
- if (ByteShift < 8 && (*Length != 0)) {
+ SubLength = mMtrrLibFixedMtrrTable[MsrNum].Length * (8 - ByteShift);
+ if (*Length < SubLength) {
return RETURN_UNSUPPORTED;
}
+ *Length -= SubLength;
+ *Base += SubLength;
+
*LastMsrNum = MsrNum;
- *ReturnClearMask = ClearMask;
- *ReturnOrMask = OrMask;
+ *ReturnClearMask = *(UINT64 *)ClearMask;
+ *ReturnOrMask = *(UINT64 *)OrMask;
return RETURN_SUCCESS;
}
|