UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c

   1 /** @file
   2   X2Apic feature.
   3
   4   Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "CpuCommonFeatures.h"
  10
  11 /**
  12   Prepares for the data used by CPU feature detection and initialization.
  13
  14   @param[in]  NumberOfProcessors  The number of CPUs in the platform.
  15
  16   @return  Pointer to a buffer of CPU related configuration data.
  17
  18   @note This service could be called by BSP only.
  19 **/
  20 VOID *
  21 EFIAPI
  22 X2ApicGetConfigData (
  23   IN UINTN  NumberOfProcessors
  24   )
  25 {
  26   BOOLEAN                            *ConfigData;
  27
  28   ConfigData = AllocateZeroPool (sizeof (BOOLEAN) * NumberOfProcessors);
  29   ASSERT (ConfigData != NULL);
  30   return ConfigData;
  31 }
  32
  33 /**
  34   Detects if X2Apci feature supported on current processor.
  35
  36   Detect if X2Apci has been already enabled.
  37
  38   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  39   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  40                                structure for the CPU executing this function.
  41   @param[in]  ConfigData       A pointer to the configuration buffer returned
  42                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  43                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  44                                RegisterCpuFeature().
  45
  46   @retval TRUE     X2Apci feature is supported.
  47   @retval FALSE    X2Apci feature is not supported.
  48
  49   @note This service could be called by BSP/APs.
  50 **/
  51 BOOLEAN
  52 EFIAPI
  53 X2ApicSupport (
  54   IN UINTN                             ProcessorNumber,
  55   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  56   IN VOID                              *ConfigData  OPTIONAL
  57   )
  58 {
  59   BOOLEAN                            *X2ApicEnabled;
  60
  61   ASSERT (ConfigData != NULL);
  62   X2ApicEnabled = (BOOLEAN *) ConfigData;
  63   //
  64   // *ConfigData indicates if X2APIC enabled on current processor
  65   //
  66   X2ApicEnabled[ProcessorNumber] = (GetApicMode () == LOCAL_APIC_MODE_X2APIC) ? TRUE : FALSE;
  67
  68   return (CpuInfo->CpuIdVersionInfoEcx.Bits.x2APIC == 1);
  69 }
  70
  71 /**
  72   Initializes X2Apci feature to specific state.
  73
  74   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  75   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  76                                structure for the CPU executing this function.
  77   @param[in]  ConfigData       A pointer to the configuration buffer returned
  78                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  79                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  80                                RegisterCpuFeature().
  81   @param[in]  State            If TRUE, then the X2Apci feature must be enabled.
  82                                If FALSE, then the X2Apci feature must be disabled.
  83
  84   @retval RETURN_SUCCESS       X2Apci feature is initialized.
  85
  86   @note This service could be called by BSP only.
  87 **/
  88 RETURN_STATUS
  89 EFIAPI
  90 X2ApicInitialize (
  91   IN UINTN                             ProcessorNumber,
  92   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  93   IN VOID                              *ConfigData,  OPTIONAL
  94   IN BOOLEAN                           State
  95   )
  96 {
  97   BOOLEAN                            *X2ApicEnabled;
  98
  99   //
 100   // The scope of the MSR_IA32_APIC_BASE is core for below processor type, only program
 101   // MSR_IA32_APIC_BASE for thread 0 in each core.
 102   //
 103   if (IS_SILVERMONT_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel)) {
 104     if (CpuInfo->ProcessorInfo.Location.Thread != 0) {
 105       return RETURN_SUCCESS;
 106     }
 107   }
 108
 109   ASSERT (ConfigData != NULL);
 110   X2ApicEnabled = (BOOLEAN *) ConfigData;
 111   if (X2ApicEnabled[ProcessorNumber]) {
 112     PRE_SMM_CPU_REGISTER_TABLE_WRITE_FIELD (
 113       ProcessorNumber,
 114       Msr,
 115       MSR_IA32_APIC_BASE,
 116       MSR_IA32_APIC_BASE_REGISTER,
 117       Bits.EXTD,
 118       1
 119       );
 120   } else {
 121     //
 122     // Enable X2APIC mode only if X2APIC is not enabled,
 123     // Needn't to disabe X2APIC mode again if X2APIC is not enabled
 124     //
 125     if (State) {
 126       CPU_REGISTER_TABLE_WRITE_FIELD (
 127         ProcessorNumber,
 128         Msr,
 129         MSR_IA32_APIC_BASE,
 130         MSR_IA32_APIC_BASE_REGISTER,
 131         Bits.EXTD,
 132         1
 133         );
 134     }
 135   }
 136   return RETURN_SUCCESS;
 137 }