UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c

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