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   Detects if X2Apci feature supported on current processor.
  19
  20   Detect if X2Apci has been already enabled.
  21
  22   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  23   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  24                                structure for the CPU executing this function.
  25   @param[in]  ConfigData       A pointer to the configuration buffer returned
  26                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  27                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  28                                RegisterCpuFeature().
  29
  30   @retval TRUE     X2Apci feature is supported.
  31   @retval FALSE    X2Apci feature is not supported.
  32
  33   @note This service could be called by BSP/APs.
  34 **/
  35 BOOLEAN
  36 EFIAPI
  37 X2ApicSupport (
  38   IN UINTN                             ProcessorNumber,
  39   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  40   IN VOID                              *ConfigData  OPTIONAL
  41   )
  42 {
  43   return (GetApicMode () == LOCAL_APIC_MODE_X2APIC);
  44 }
  45
  46 /**
  47   Initializes X2Apci feature to specific state.
  48
  49   @param[in]  ProcessorNumber  The index of the CPU executing this function.
  50   @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
  51                                structure for the CPU executing this function.
  52   @param[in]  ConfigData       A pointer to the configuration buffer returned
  53                                by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
  54                                CPU_FEATURE_GET_CONFIG_DATA was not provided in
  55                                RegisterCpuFeature().
  56   @param[in]  State            If TRUE, then the X2Apci feature must be enabled.
  57                                If FALSE, then the X2Apci feature must be disabled.
  58
  59   @retval RETURN_SUCCESS       X2Apci feature is initialized.
  60
  61   @note This service could be called by BSP only.
  62 **/
  63 RETURN_STATUS
  64 EFIAPI
  65 X2ApicInitialize (
  66   IN UINTN                             ProcessorNumber,
  67   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
  68   IN VOID                              *ConfigData,  OPTIONAL
  69   IN BOOLEAN                           State
  70   )
  71 {
  72   PRE_SMM_CPU_REGISTER_TABLE_WRITE_FIELD (
  73     ProcessorNumber,
  74     Msr,
  75     MSR_IA32_APIC_BASE,
  76     MSR_IA32_APIC_BASE_REGISTER,
  77     Bits.EXTD,
  78     (State) ? 1 : 0
  79     );
  80   return RETURN_SUCCESS;
  81 }