1 files changed, 106 insertions, 0 deletions
diff --git a/Core/UefiCpuPkg/Library/CpuCommonFeaturesLib/ClockModulation.c b/Core/UefiCpuPkg/Library/CpuCommonFeaturesLib/ClockModulation.c
new file mode 100644
index 0000000000..56e53561e9
--- /dev/null
+++ b/Core/UefiCpuPkg/Library/CpuCommonFeaturesLib/ClockModulation.c
@@ -0,0 +1,106 @@
+/** @file
+  Clock Modulation feature.
+
+  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "CpuCommonFeatures.h"
+
+/**
+  Detects if Clock Modulation feature supported on current processor.
+
+  @param[in]  ProcessorNumber  The index of the CPU executing this function.
+  @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
+                               structure for the CPU executing this function.
+  @param[in]  ConfigData       A pointer to the configuration buffer returned
+                               by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
+                               CPU_FEATURE_GET_CONFIG_DATA was not provided in
+                               RegisterCpuFeature().
+
+  @retval TRUE     Clock Modulation feature is supported.
+  @retval FALSE    Clock Modulation feature is not supported.
+
+  @note This service could be called by BSP/APs.
+**/
+BOOLEAN
+EFIAPI
+ClockModulationSupport (
+  IN UINTN                             ProcessorNumber,
+  IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
+  IN VOID                              *ConfigData  OPTIONAL
+  )
+{
+  return (CpuInfo->CpuIdVersionInfoEdx.Bits.ACPI == 1);
+}
+
+/**
+  Initializes Clock Modulation feature to specific state.
+
+  @param[in]  ProcessorNumber  The index of the CPU executing this function.
+  @param[in]  CpuInfo          A pointer to the REGISTER_CPU_FEATURE_INFORMATION
+                               structure for the CPU executing this function.
+  @param[in]  ConfigData       A pointer to the configuration buffer returned
+                               by CPU_FEATURE_GET_CONFIG_DATA.  NULL if
+                               CPU_FEATURE_GET_CONFIG_DATA was not provided in
+                               RegisterCpuFeature().
+  @param[in]  State            If TRUE, then the Clock Modulation feature must be enabled.
+                               If FALSE, then the Clock Modulation feature must be disabled.
+
+  @retval RETURN_SUCCESS       Clock Modulation feature is initialized.
+
+  @note This service could be called by BSP only.
+**/
+RETURN_STATUS
+EFIAPI
+ClockModulationInitialize (
+  IN UINTN                             ProcessorNumber,
+  IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
+  IN VOID                              *ConfigData,  OPTIONAL
+  IN BOOLEAN                           State
+  )
+{
+  if (IS_SANDY_BRIDGE_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel)) {
+    CPU_REGISTER_TABLE_WRITE_FIELD (
+      ProcessorNumber,
+      Msr,
+      MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION,
+      MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION_REGISTER,
+      Bits.OnDemandClockModulationDutyCycle,
+      PcdGet8 (PcdCpuClockModulationDutyCycle)
+      );
+    CPU_REGISTER_TABLE_WRITE_FIELD (
+      ProcessorNumber,
+      Msr,
+      MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION,
+      MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION_REGISTER,
+      Bits.OnDemandClockModulationEnable,
+      (State) ? 1 : 0
+      );
+  } else {
+    CPU_REGISTER_TABLE_WRITE_FIELD (
+      ProcessorNumber,
+      Msr,
+      MSR_IA32_CLOCK_MODULATION,
+      MSR_IA32_CLOCK_MODULATION_REGISTER,
+      Bits.OnDemandClockModulationDutyCycle,
+      PcdGet8 (PcdCpuClockModulationDutyCycle)
+      );
+    CPU_REGISTER_TABLE_WRITE_FIELD (
+      ProcessorNumber,
+      Msr,
+      MSR_IA32_CLOCK_MODULATION,
+      MSR_IA32_CLOCK_MODULATION_REGISTER,
+      Bits.OnDemandClockModulationEnable,
+      (State) ? 1 : 0
+      );
+  }
+  return RETURN_SUCCESS;
+}