UefiCpuPkg/Library/CpuCommonFeaturesLib/Lmce.c

   1 /** @file
   2   Local machine check exception feature.
   3
   4   Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "CpuCommonFeatures.h"
  16
  17 /**
  18   Detects if Local machine check exception feature supported on current
  19   processor.
  20
  21   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  22   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  23                                structure for the CPU executing this function.
  24   @param[in]  ConfigData       A pointer to the configuration buffer returned
  25                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  26                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  27                                RegisterCpuFeature().
  28
  29   @retval TRUE     Local machine check exception feature is supported.
  30   @retval FALSE    Local machine check exception feature is not supported.
  31
  32   @note This service could be called by BSP/APs.
  33 **/
  34 BOOLEAN
  35 EFIAPI
  36 LmceSupport (
  37   IN UINTN                             ProcessorNumber,
  38   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  39   IN VOID                              *ConfigData  OPTIONAL
  40   )
  41 {
  42   MSR_IA32_MCG_CAP_REGISTER    McgCap;
  43
  44   McgCap.Uint64 = AsmReadMsr64 (MSR_IA32_MCG_CAP);
  45   if (ProcessorNumber == 0) {
  46     DEBUG ((EFI_D_INFO, "LMCE eanble = %x\n", (BOOLEAN) (McgCap.Bits.MCG_LMCE_P != 0)));
  47   }
  48   return (BOOLEAN) (McgCap.Bits.MCG_LMCE_P != 0);
  49 }
  50
  51 /**
  52   Initializes Local machine check exception feature to specific state.
  53
  54   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  55   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  56                                structure for the CPU executing this function.
  57   @param[in]  ConfigData       A pointer to the configuration buffer returned
  58                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  59                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  60                                RegisterCpuFeature().
  61   @param[in]  State            If TRUE, then the Local machine check exception
  62                                feature must be enabled.
  63                                If FALSE, then the Local machine check exception
  64                                feature must be disabled.
  65
  66   @retval RETURN_SUCCESS       Local machine check exception feature is initialized.
  67
  68 **/
  69 RETURN_STATUS
  70 EFIAPI
  71 LmceInitialize (
  72   IN UINTN                             ProcessorNumber,
  73   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  74   IN VOID                              *ConfigData,  OPTIONAL
  75   IN BOOLEAN                           State
  76   )
  77 {
  78   MSR_IA32_FEATURE_CONTROL_REGISTER    *MsrRegister;
  79
  80   ASSERT (ConfigData != NULL);
  81   MsrRegister = (MSR_IA32_FEATURE_CONTROL_REGISTER *) ConfigData;
  82   if (MsrRegister[ProcessorNumber].Bits.Lock == 0) {
  83     CPU_REGISTER_TABLE_WRITE_FIELD (
  84       ProcessorNumber,
  85       Msr,
  86       MSR_IA32_FEATURE_CONTROL,
  87       MSR_IA32_FEATURE_CONTROL_REGISTER,
  88       Bits.LmceOn,
  89       (State) ? 1 : 0
  90       );
  91   }
  92   return RETURN_SUCCESS;
  93 }