diff options
| author | Dong, Eric <eric.dong@intel.com> | 2019-08-16 11:57:27 +0800 |
|---|---|---|
| committer | Ray Ni <ray.ni@intel.com> | 2019-08-21 02:44:49 +0800 |
| commit | cfbcaad25189c02627bf5c73ddeb25b91516f7d6 (patch) | |
| tree | d8f3374535afa0952e78a52f73675742347c6732 /UefiCpuPkg/PiSmmCpuDxeSmm | |
| parent | ef21a304e047eb3cc7f79c6c4c16233f5b7abd7e (diff) | |
| download | edk2-cfbcaad25189c02627bf5c73ddeb25b91516f7d6.tar.gz edk2-cfbcaad25189c02627bf5c73ddeb25b91516f7d6.tar.bz2 edk2-cfbcaad25189c02627bf5c73ddeb25b91516f7d6.zip | |
UefiCpuPkg/PiSmmCpuDxeSmm: Supports test then write new value logic.
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2040
Supports new logic which test current value before write new value.
Only write new value when current value not same as new value.
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Diffstat (limited to 'UefiCpuPkg/PiSmmCpuDxeSmm')
| -rw-r--r-- | UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c index 627a3b87ac..ba5cc0194c 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c @@ -241,6 +241,7 @@ ProgramProcessorRegister ( UINTN ValidThreadCount;
UINT32 *ValidCoreCountPerPackage;
EFI_STATUS Status;
+ UINT64 CurrentValue;
//
// Traverse Register Table of this logical processor
@@ -263,6 +264,16 @@ ProgramProcessorRegister ( if (EFI_ERROR (Status)) {
break;
}
+ if (RegisterTableEntry->TestThenWrite) {
+ CurrentValue = BitFieldRead64 (
+ Value,
+ RegisterTableEntry->ValidBitStart,
+ RegisterTableEntry->ValidBitStart + RegisterTableEntry->ValidBitLength - 1
+ );
+ if (CurrentValue == RegisterTableEntry->Value) {
+ break;
+ }
+ }
Value = (UINTN) BitFieldWrite64 (
Value,
RegisterTableEntry->ValidBitStart,
@@ -275,6 +286,24 @@ ProgramProcessorRegister ( // The specified register is Model Specific Register
//
case Msr:
+ if (RegisterTableEntry->TestThenWrite) {
+ Value = (UINTN)AsmReadMsr64 (RegisterTableEntry->Index);
+ if (RegisterTableEntry->ValidBitLength >= 64) {
+ if (Value == RegisterTableEntry->Value) {
+ break;
+ }
+ } else {
+ CurrentValue = BitFieldRead64 (
+ Value,
+ RegisterTableEntry->ValidBitStart,
+ RegisterTableEntry->ValidBitStart + RegisterTableEntry->ValidBitLength - 1
+ );
+ if (CurrentValue == RegisterTableEntry->Value) {
+ break;
+ }
+ }
+ }
+
//
// If this function is called to restore register setting after INIT signal,
// there is no need to restore MSRs in register table.
|