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| author | Leo Duran <leo.duran@amd.com> | 2020-02-29 23:05:45 +0800 |
|---|---|---|
| committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2020-03-02 05:47:06 +0000 |
| commit | 4c0f6e349d32cf27a7104ddd3e729d6ebc88ea70 (patch) | |
| tree | bdf7a7b9ac9652b084c9d3fc2a7cfae9376b005f /UefiCpuPkg/Library/MpInitLib/MpLib.c | |
| parent | 2be4828af1c92a848af90429a9a0b44544c80553 (diff) | |
| download | edk2-4c0f6e349d32cf27a7104ddd3e729d6ebc88ea70.tar.gz edk2-4c0f6e349d32cf27a7104ddd3e729d6ebc88ea70.tar.bz2 edk2-4c0f6e349d32cf27a7104ddd3e729d6ebc88ea70.zip | |
UefiCpuPkg/MpInitLib: Skip reading PlatformId on AMD processors.edk2-stable202002
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2556
This patch uses CPUID signature check to skip reading the PlatformId MSR,
which is not implemented on AMD processors.
The PlatformId is used for loading microcode patches, which is also not
supported and AMD-based platforms. To mitigate the PlatformId dependency,
PcdCpuMicrocodePatchAddress and PcdCpuMicrodePatchRegionSize must be set
to 0 (default value), in order to bypass microcode loading code paths.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Leo Duran <leo.duran@amd.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Diffstat (limited to 'UefiCpuPkg/Library/MpInitLib/MpLib.c')
| -rw-r--r-- | UefiCpuPkg/Library/MpInitLib/MpLib.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c index d0fbc17ce5..64a4c3546e 100644 --- a/UefiCpuPkg/Library/MpInitLib/MpLib.c +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c @@ -2,6 +2,8 @@ CPU MP Initialize Library common functions.
Copyright (c) 2016 - 2020, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2020, AMD Inc. All rights reserved.<BR>
+
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
@@ -10,6 +12,30 @@ EFI_GUID mCpuInitMpLibHobGuid = CPU_INIT_MP_LIB_HOB_GUID;
+
+/**
+ Determine if the standard CPU signature is "AuthenticAMD".
+
+ @retval TRUE The CPU signature matches.
+ @retval FALSE The CPU signature does not match.
+
+**/
+STATIC
+BOOLEAN
+StandardSignatureIsAuthenticAMD (
+ VOID
+ )
+{
+ UINT32 RegEbx;
+ UINT32 RegEcx;
+ UINT32 RegEdx;
+
+ AsmCpuid (CPUID_SIGNATURE, NULL, &RegEbx, &RegEcx, &RegEdx);
+ return (RegEbx == CPUID_SIGNATURE_AUTHENTIC_AMD_EBX &&
+ RegEcx == CPUID_SIGNATURE_AUTHENTIC_AMD_ECX &&
+ RegEdx == CPUID_SIGNATURE_AUTHENTIC_AMD_EDX);
+}
+
/**
The function will check if BSP Execute Disable is enabled.
@@ -564,8 +590,13 @@ InitializeApData ( CpuMpData->CpuData[ProcessorNumber].Waiting = FALSE;
CpuMpData->CpuData[ProcessorNumber].CpuHealthy = (BistData == 0) ? TRUE : FALSE;
- PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
- CpuMpData->CpuData[ProcessorNumber].PlatformId = (UINT8) PlatformIdMsr.Bits.PlatformId;
+ //
+ // NOTE: PlatformId is not relevant on AMD platforms.
+ //
+ if (!StandardSignatureIsAuthenticAMD ()) {
+ PlatformIdMsr.Uint64 = AsmReadMsr64 (MSR_IA32_PLATFORM_ID);
+ CpuMpData->CpuData[ProcessorNumber].PlatformId = (UINT8)PlatformIdMsr.Bits.PlatformId;
+ }
AsmCpuid (
CPUID_VERSION_INFO,
|