UefiCpuPkg: Add NULL CPU Common Features Library instance
[mirror_edk2.git] / UefiCpuPkg / Library / CpuCommonFeaturesLib / ClockModulation.c
1 /** @file
2 Clock Modulation 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 Clock Modulation feature supported on current processor.
19
20 @param[in] ProcessorNumber The index of the CPU executing this function.
21 @param[in] CpuInfo A pointer to the REGISTER_CPU_FEATURE_INFORMATION
22 structure for the CPU executing this function.
23 @param[in] ConfigData A pointer to the configuration buffer returned
24 by CPU_FEATURE_GET_CONFIG_DATA. NULL if
25 CPU_FEATURE_GET_CONFIG_DATA was not provided in
26 RegisterCpuFeature().
27
28 @retval TRUE Clock Modulation feature is supported.
29 @retval FALSE Clock Modulation feature is not supported.
30
31 @note This service could be called by BSP/APs.
32 **/
33 BOOLEAN
34 EFIAPI
35 ClockModulationSupport (
36 IN UINTN ProcessorNumber,
37 IN REGISTER_CPU_FEATURE_INFORMATION *CpuInfo,
38 IN VOID *ConfigData OPTIONAL
39 )
40 {
41 return (CpuInfo->CpuIdVersionInfoEdx.Bits.ACPI == 1);
42 }
43
44 /**
45 Initializes Clock Modulation feature to specific state.
46
47 @param[in] ProcessorNumber The index of the CPU executing this function.
48 @param[in] CpuInfo A pointer to the REGISTER_CPU_FEATURE_INFORMATION
49 structure for the CPU executing this function.
50 @param[in] ConfigData A pointer to the configuration buffer returned
51 by CPU_FEATURE_GET_CONFIG_DATA. NULL if
52 CPU_FEATURE_GET_CONFIG_DATA was not provided in
53 RegisterCpuFeature().
54 @param[in] State If TRUE, then the Clock Modulation feature must be enabled.
55 If FALSE, then the Clock Modulation feature must be disabled.
56
57 @retval RETURN_SUCCESS Clock Modulation feature is initialized.
58
59 @note This service could be called by BSP only.
60 **/
61 RETURN_STATUS
62 EFIAPI
63 ClockModulationInitialize (
64 IN UINTN ProcessorNumber,
65 IN REGISTER_CPU_FEATURE_INFORMATION *CpuInfo,
66 IN VOID *ConfigData, OPTIONAL
67 IN BOOLEAN State
68 )
69 {
70 if (IS_SANDY_BRIDGE_PROCESSOR (CpuInfo->DisplayFamily, CpuInfo->DisplayModel)) {
71 CPU_REGISTER_TABLE_WRITE_FIELD (
72 ProcessorNumber,
73 Msr,
74 MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION,
75 MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION_REGISTER,
76 Bits.OnDemandClockModulationDutyCycle,
77 PcdGet8 (PcdCpuClockModulationDutyCycle)
78 );
79 CPU_REGISTER_TABLE_WRITE_FIELD (
80 ProcessorNumber,
81 Msr,
82 MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION,
83 MSR_SANDY_BRIDGE_IA32_CLOCK_MODULATION_REGISTER,
84 Bits.OnDemandClockModulationEnable,
85 (State) ? 1 : 0
86 );
87 } else {
88 CPU_REGISTER_TABLE_WRITE_FIELD (
89 ProcessorNumber,
90 Msr,
91 MSR_IA32_CLOCK_MODULATION,
92 MSR_IA32_CLOCK_MODULATION_REGISTER,
93 Bits.OnDemandClockModulationDutyCycle,
94 PcdGet8 (PcdCpuClockModulationDutyCycle)
95 );
96 CPU_REGISTER_TABLE_WRITE_FIELD (
97 ProcessorNumber,
98 Msr,
99 MSR_IA32_CLOCK_MODULATION,
100 MSR_IA32_CLOCK_MODULATION_REGISTER,
101 Bits.OnDemandClockModulationEnable,
102 (State) ? 1 : 0
103 );
104 }
105 return RETURN_SUCCESS;
106 }