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