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UefiCpuPkg/MtrrLib: IsMtrrSupported uses definitions in Msr.h 

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
This commit is contained in:
Ruiyu Ni 2016-09-02 10:27:29 +08:00
parent 78c4992529
commit 3bb13d35d6
1 changed files with 11 additions and 9 deletions
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20
UefiCpuPkg/Library/MtrrLib/MtrrLib.c
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@ -18,6 +18,9 @@
#include <Base.h>
#include <Register/Cpuid.h>
#include <Register/Msr.h>
#include <Library/MtrrLib.h>
#include <Library/BaseLib.h>
#include <Library/CpuLib.h>
@ -2124,26 +2127,25 @@ IsMtrrSupported (
VOID
)
{
UINT32 RegEdx;
UINT64 MtrrCap;
CPUID_VERSION_INFO_EDX Edx;
MSR_IA32_MTRRCAP_REGISTER MtrrCap;
//
// Check CPUID(1).EDX[12] for MTRR capability
//
AsmCpuid (1, NULL, NULL, NULL, &RegEdx);
if (BitFieldRead32 (RegEdx, 12, 12) == 0) {
AsmCpuid (CPUID_VERSION_INFO, NULL, NULL, NULL, &Edx.Uint32);
if (Edx.Bits.MTRR == 0) {
return FALSE;
}
//
// Check IA32_MTRRCAP.[0..7] for number of variable MTRRs and IA32_MTRRCAP[8] for
// fixed MTRRs existence. If number of variable MTRRs is zero, or fixed MTRRs do not
// Check number of variable MTRRs and fixed MTRRs existence.
// If number of variable MTRRs is zero, or fixed MTRRs do not
// exist, return false.
//
MtrrCap = AsmReadMsr64 (MTRR_LIB_IA32_MTRR_CAP);
if ((BitFieldRead64 (MtrrCap, 0, 7) == 0) || (BitFieldRead64 (MtrrCap, 8, 8) == 0)) {
MtrrCap.Uint64 = AsmReadMsr64 (MSR_IA32_MTRRCAP);
if ((MtrrCap.Bits.VCNT == 0) || (MtrrCap.Bits.FIX == 0)) {
return FALSE;
}
return TRUE;
}