1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * AMD Processor P-state Frequency Driver Unit Test 4 * 5 * Copyright (C) 2022 Advanced Micro Devices, Inc. All Rights Reserved. 6 * 7 * Author: Meng Li <li.meng@amd.com> 8 * 9 * The AMD P-State Unit Test is a test module for testing the amd-pstate 10 * driver. 1) It can help all users to verify their processor support 11 * (SBIOS/Firmware or Hardware). 2) Kernel can have a basic function 12 * test to avoid the kernel regression during the update. 3) We can 13 * introduce more functional or performance tests to align the result 14 * together, it will benefit power and performance scale optimization. 15 * 16 * This driver implements basic framework with plans to enhance it with 17 * additional test cases to improve the depth and coverage of the test. 18 * 19 * See Documentation/admin-guide/pm/amd-pstate.rst Unit Tests for 20 * amd-pstate to get more detail. 21 */ 22 23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 24 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/moduleparam.h> 28 #include <linux/fs.h> 29 30 #include <acpi/cppc_acpi.h> 31 32 #include "amd-pstate.h" 33 34 /* 35 * Abbreviations: 36 * amd_pstate_ut: used as a shortform for AMD P-State unit test. 37 * It helps to keep variable names smaller, simpler 38 */ 39 enum amd_pstate_ut_result { 40 AMD_PSTATE_UT_RESULT_PASS, 41 AMD_PSTATE_UT_RESULT_FAIL, 42 }; 43 44 struct amd_pstate_ut_struct { 45 const char *name; 46 void (*func)(u32 index); 47 enum amd_pstate_ut_result result; 48 }; 49 50 /* 51 * Kernel module for testing the AMD P-State unit test 52 */ 53 static void amd_pstate_ut_acpi_cpc_valid(u32 index); 54 static void amd_pstate_ut_check_enabled(u32 index); 55 static void amd_pstate_ut_check_perf(u32 index); 56 static void amd_pstate_ut_check_freq(u32 index); 57 58 static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = { 59 {"amd_pstate_ut_acpi_cpc_valid", amd_pstate_ut_acpi_cpc_valid }, 60 {"amd_pstate_ut_check_enabled", amd_pstate_ut_check_enabled }, 61 {"amd_pstate_ut_check_perf", amd_pstate_ut_check_perf }, 62 {"amd_pstate_ut_check_freq", amd_pstate_ut_check_freq } 63 }; 64 65 static bool get_shared_mem(void) 66 { 67 bool result = false; 68 69 if (!boot_cpu_has(X86_FEATURE_CPPC)) 70 result = true; 71 72 return result; 73 } 74 75 /* 76 * check the _CPC object is present in SBIOS. 77 */ 78 static void amd_pstate_ut_acpi_cpc_valid(u32 index) 79 { 80 if (acpi_cpc_valid()) 81 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 82 else { 83 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 84 pr_err("%s the _CPC object is not present in SBIOS!\n", __func__); 85 } 86 } 87 88 static void amd_pstate_ut_pstate_enable(u32 index) 89 { 90 int ret = 0; 91 u64 cppc_enable = 0; 92 93 ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable); 94 if (ret) { 95 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 96 pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d error!\n", __func__, ret); 97 return; 98 } 99 if (cppc_enable) 100 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 101 else { 102 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 103 pr_err("%s amd pstate must be enabled!\n", __func__); 104 } 105 } 106 107 /* 108 * check if amd pstate is enabled 109 */ 110 static void amd_pstate_ut_check_enabled(u32 index) 111 { 112 if (get_shared_mem()) 113 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 114 else 115 amd_pstate_ut_pstate_enable(index); 116 } 117 118 /* 119 * check if performance values are reasonable. 120 * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0 121 */ 122 static void amd_pstate_ut_check_perf(u32 index) 123 { 124 int cpu = 0, ret = 0; 125 u32 highest_perf = 0, nominal_perf = 0, lowest_nonlinear_perf = 0, lowest_perf = 0; 126 u64 cap1 = 0; 127 struct cppc_perf_caps cppc_perf; 128 struct cpufreq_policy *policy = NULL; 129 struct amd_cpudata *cpudata = NULL; 130 131 for_each_possible_cpu(cpu) { 132 policy = cpufreq_cpu_get(cpu); 133 if (!policy) 134 break; 135 cpudata = policy->driver_data; 136 137 if (get_shared_mem()) { 138 ret = cppc_get_perf_caps(cpu, &cppc_perf); 139 if (ret) { 140 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 141 pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret); 142 goto skip_test; 143 } 144 145 highest_perf = cppc_perf.highest_perf; 146 nominal_perf = cppc_perf.nominal_perf; 147 lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; 148 lowest_perf = cppc_perf.lowest_perf; 149 } else { 150 ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1); 151 if (ret) { 152 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 153 pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret); 154 goto skip_test; 155 } 156 157 highest_perf = AMD_CPPC_HIGHEST_PERF(cap1); 158 nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1); 159 lowest_nonlinear_perf = AMD_CPPC_LOWNONLIN_PERF(cap1); 160 lowest_perf = AMD_CPPC_LOWEST_PERF(cap1); 161 } 162 163 if ((highest_perf != READ_ONCE(cpudata->highest_perf)) || 164 (nominal_perf != READ_ONCE(cpudata->nominal_perf)) || 165 (lowest_nonlinear_perf != READ_ONCE(cpudata->lowest_nonlinear_perf)) || 166 (lowest_perf != READ_ONCE(cpudata->lowest_perf))) { 167 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 168 pr_err("%s cpu%d highest=%d %d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d, they should be equal!\n", 169 __func__, cpu, highest_perf, cpudata->highest_perf, 170 nominal_perf, cpudata->nominal_perf, 171 lowest_nonlinear_perf, cpudata->lowest_nonlinear_perf, 172 lowest_perf, cpudata->lowest_perf); 173 goto skip_test; 174 } 175 176 if (!((highest_perf >= nominal_perf) && 177 (nominal_perf > lowest_nonlinear_perf) && 178 (lowest_nonlinear_perf > lowest_perf) && 179 (lowest_perf > 0))) { 180 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 181 pr_err("%s cpu%d highest=%d >= nominal=%d > lowest_nonlinear=%d > lowest=%d > 0, the formula is incorrect!\n", 182 __func__, cpu, highest_perf, nominal_perf, 183 lowest_nonlinear_perf, lowest_perf); 184 goto skip_test; 185 } 186 cpufreq_cpu_put(policy); 187 } 188 189 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 190 return; 191 skip_test: 192 cpufreq_cpu_put(policy); 193 } 194 195 /* 196 * Check if frequency values are reasonable. 197 * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 198 * check max freq when set support boost mode. 199 */ 200 static void amd_pstate_ut_check_freq(u32 index) 201 { 202 int cpu = 0; 203 struct cpufreq_policy *policy = NULL; 204 struct amd_cpudata *cpudata = NULL; 205 u32 nominal_freq_khz; 206 207 for_each_possible_cpu(cpu) { 208 policy = cpufreq_cpu_get(cpu); 209 if (!policy) 210 break; 211 cpudata = policy->driver_data; 212 213 nominal_freq_khz = cpudata->nominal_freq*1000; 214 if (!((cpudata->max_freq >= nominal_freq_khz) && 215 (nominal_freq_khz > cpudata->lowest_nonlinear_freq) && 216 (cpudata->lowest_nonlinear_freq > cpudata->min_freq) && 217 (cpudata->min_freq > 0))) { 218 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 219 pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n", 220 __func__, cpu, cpudata->max_freq, nominal_freq_khz, 221 cpudata->lowest_nonlinear_freq, cpudata->min_freq); 222 goto skip_test; 223 } 224 225 if (cpudata->min_freq != policy->min) { 226 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 227 pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d, they should be equal!\n", 228 __func__, cpu, cpudata->min_freq, policy->min); 229 goto skip_test; 230 } 231 232 if (cpudata->boost_supported) { 233 if ((policy->max == cpudata->max_freq) || 234 (policy->max == nominal_freq_khz)) 235 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 236 else { 237 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 238 pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n", 239 __func__, cpu, policy->max, cpudata->max_freq, 240 nominal_freq_khz); 241 goto skip_test; 242 } 243 } else { 244 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 245 pr_err("%s cpu%d must support boost!\n", __func__, cpu); 246 goto skip_test; 247 } 248 cpufreq_cpu_put(policy); 249 } 250 251 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 252 return; 253 skip_test: 254 cpufreq_cpu_put(policy); 255 } 256 257 static int __init amd_pstate_ut_init(void) 258 { 259 u32 i = 0, arr_size = ARRAY_SIZE(amd_pstate_ut_cases); 260 261 for (i = 0; i < arr_size; i++) { 262 amd_pstate_ut_cases[i].func(i); 263 switch (amd_pstate_ut_cases[i].result) { 264 case AMD_PSTATE_UT_RESULT_PASS: 265 pr_info("%-4d %-20s\t success!\n", i+1, amd_pstate_ut_cases[i].name); 266 break; 267 case AMD_PSTATE_UT_RESULT_FAIL: 268 default: 269 pr_info("%-4d %-20s\t fail!\n", i+1, amd_pstate_ut_cases[i].name); 270 break; 271 } 272 } 273 274 return 0; 275 } 276 277 static void __exit amd_pstate_ut_exit(void) 278 { 279 } 280 281 module_init(amd_pstate_ut_init); 282 module_exit(amd_pstate_ut_exit); 283 284 MODULE_AUTHOR("Meng Li <li.meng@amd.com>"); 285 MODULE_DESCRIPTION("AMD P-state driver Test module"); 286 MODULE_LICENSE("GPL"); 287