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 static void amd_pstate_ut_check_driver(u32 index); 58 59 static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = { 60 {"amd_pstate_ut_acpi_cpc_valid", amd_pstate_ut_acpi_cpc_valid }, 61 {"amd_pstate_ut_check_enabled", amd_pstate_ut_check_enabled }, 62 {"amd_pstate_ut_check_perf", amd_pstate_ut_check_perf }, 63 {"amd_pstate_ut_check_freq", amd_pstate_ut_check_freq }, 64 {"amd_pstate_ut_check_driver", amd_pstate_ut_check_driver } 65 }; 66 67 static bool get_shared_mem(void) 68 { 69 bool result = false; 70 71 if (!boot_cpu_has(X86_FEATURE_CPPC)) 72 result = true; 73 74 return result; 75 } 76 77 /* 78 * check the _CPC object is present in SBIOS. 79 */ 80 static void amd_pstate_ut_acpi_cpc_valid(u32 index) 81 { 82 if (acpi_cpc_valid()) 83 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 84 else { 85 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 86 pr_err("%s the _CPC object is not present in SBIOS!\n", __func__); 87 } 88 } 89 90 static void amd_pstate_ut_pstate_enable(u32 index) 91 { 92 int ret = 0; 93 u64 cppc_enable = 0; 94 95 ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable); 96 if (ret) { 97 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 98 pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d error!\n", __func__, ret); 99 return; 100 } 101 if (cppc_enable) 102 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 103 else { 104 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 105 pr_err("%s amd pstate must be enabled!\n", __func__); 106 } 107 } 108 109 /* 110 * check if amd pstate is enabled 111 */ 112 static void amd_pstate_ut_check_enabled(u32 index) 113 { 114 if (get_shared_mem()) 115 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 116 else 117 amd_pstate_ut_pstate_enable(index); 118 } 119 120 /* 121 * check if performance values are reasonable. 122 * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0 123 */ 124 static void amd_pstate_ut_check_perf(u32 index) 125 { 126 int cpu = 0, ret = 0; 127 u32 highest_perf = 0, nominal_perf = 0, lowest_nonlinear_perf = 0, lowest_perf = 0; 128 u64 cap1 = 0; 129 struct cppc_perf_caps cppc_perf; 130 struct cpufreq_policy *policy = NULL; 131 struct amd_cpudata *cpudata = NULL; 132 133 for_each_possible_cpu(cpu) { 134 policy = cpufreq_cpu_get(cpu); 135 if (!policy) 136 break; 137 cpudata = policy->driver_data; 138 139 if (get_shared_mem()) { 140 ret = cppc_get_perf_caps(cpu, &cppc_perf); 141 if (ret) { 142 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 143 pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret); 144 goto skip_test; 145 } 146 147 highest_perf = cppc_perf.highest_perf; 148 nominal_perf = cppc_perf.nominal_perf; 149 lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; 150 lowest_perf = cppc_perf.lowest_perf; 151 } else { 152 ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1); 153 if (ret) { 154 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 155 pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret); 156 goto skip_test; 157 } 158 159 highest_perf = AMD_CPPC_HIGHEST_PERF(cap1); 160 nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1); 161 lowest_nonlinear_perf = AMD_CPPC_LOWNONLIN_PERF(cap1); 162 lowest_perf = AMD_CPPC_LOWEST_PERF(cap1); 163 } 164 165 if (highest_perf != READ_ONCE(cpudata->highest_perf) && !cpudata->hw_prefcore) { 166 pr_err("%s cpu%d highest=%d %d highest perf doesn't match\n", 167 __func__, cpu, highest_perf, cpudata->highest_perf); 168 goto skip_test; 169 } 170 if ((nominal_perf != READ_ONCE(cpudata->nominal_perf)) || 171 (lowest_nonlinear_perf != READ_ONCE(cpudata->lowest_nonlinear_perf)) || 172 (lowest_perf != READ_ONCE(cpudata->lowest_perf))) { 173 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 174 pr_err("%s cpu%d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d, they should be equal!\n", 175 __func__, cpu, nominal_perf, cpudata->nominal_perf, 176 lowest_nonlinear_perf, cpudata->lowest_nonlinear_perf, 177 lowest_perf, cpudata->lowest_perf); 178 goto skip_test; 179 } 180 181 if (!((highest_perf >= nominal_perf) && 182 (nominal_perf > lowest_nonlinear_perf) && 183 (lowest_nonlinear_perf > lowest_perf) && 184 (lowest_perf > 0))) { 185 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 186 pr_err("%s cpu%d highest=%d >= nominal=%d > lowest_nonlinear=%d > lowest=%d > 0, the formula is incorrect!\n", 187 __func__, cpu, highest_perf, nominal_perf, 188 lowest_nonlinear_perf, lowest_perf); 189 goto skip_test; 190 } 191 cpufreq_cpu_put(policy); 192 } 193 194 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 195 return; 196 skip_test: 197 cpufreq_cpu_put(policy); 198 } 199 200 /* 201 * Check if frequency values are reasonable. 202 * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 203 * check max freq when set support boost mode. 204 */ 205 static void amd_pstate_ut_check_freq(u32 index) 206 { 207 int cpu = 0; 208 struct cpufreq_policy *policy = NULL; 209 struct amd_cpudata *cpudata = NULL; 210 u32 nominal_freq_khz; 211 212 for_each_possible_cpu(cpu) { 213 policy = cpufreq_cpu_get(cpu); 214 if (!policy) 215 break; 216 cpudata = policy->driver_data; 217 218 nominal_freq_khz = cpudata->nominal_freq*1000; 219 if (!((cpudata->max_freq >= nominal_freq_khz) && 220 (nominal_freq_khz > cpudata->lowest_nonlinear_freq) && 221 (cpudata->lowest_nonlinear_freq > cpudata->min_freq) && 222 (cpudata->min_freq > 0))) { 223 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 224 pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n", 225 __func__, cpu, cpudata->max_freq, nominal_freq_khz, 226 cpudata->lowest_nonlinear_freq, cpudata->min_freq); 227 goto skip_test; 228 } 229 230 if (cpudata->lowest_nonlinear_freq != policy->min) { 231 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 232 pr_err("%s cpu%d cpudata_lowest_nonlinear_freq=%d policy_min=%d, they should be equal!\n", 233 __func__, cpu, cpudata->lowest_nonlinear_freq, policy->min); 234 goto skip_test; 235 } 236 237 if (cpudata->boost_supported) { 238 if ((policy->max == cpudata->max_freq) || 239 (policy->max == nominal_freq_khz)) 240 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 241 else { 242 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 243 pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n", 244 __func__, cpu, policy->max, cpudata->max_freq, 245 nominal_freq_khz); 246 goto skip_test; 247 } 248 } else { 249 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; 250 pr_err("%s cpu%d must support boost!\n", __func__, cpu); 251 goto skip_test; 252 } 253 cpufreq_cpu_put(policy); 254 } 255 256 amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; 257 return; 258 skip_test: 259 cpufreq_cpu_put(policy); 260 } 261 262 static int amd_pstate_set_mode(enum amd_pstate_mode mode) 263 { 264 const char *mode_str = amd_pstate_get_mode_string(mode); 265 266 pr_debug("->setting mode to %s\n", mode_str); 267 268 return amd_pstate_update_status(mode_str, strlen(mode_str)); 269 } 270 271 static void amd_pstate_ut_check_driver(u32 index) 272 { 273 enum amd_pstate_mode mode1, mode2 = AMD_PSTATE_DISABLE; 274 int ret; 275 276 for (mode1 = AMD_PSTATE_DISABLE; mode1 < AMD_PSTATE_MAX; mode1++) { 277 ret = amd_pstate_set_mode(mode1); 278 if (ret) 279 goto out; 280 for (mode2 = AMD_PSTATE_DISABLE; mode2 < AMD_PSTATE_MAX; mode2++) { 281 if (mode1 == mode2) 282 continue; 283 ret = amd_pstate_set_mode(mode2); 284 if (ret) 285 goto out; 286 } 287 } 288 out: 289 if (ret) 290 pr_warn("%s: failed to update status for %s->%s: %d\n", __func__, 291 amd_pstate_get_mode_string(mode1), 292 amd_pstate_get_mode_string(mode2), ret); 293 294 amd_pstate_ut_cases[index].result = ret ? 295 AMD_PSTATE_UT_RESULT_FAIL : 296 AMD_PSTATE_UT_RESULT_PASS; 297 } 298 299 static int __init amd_pstate_ut_init(void) 300 { 301 u32 i = 0, arr_size = ARRAY_SIZE(amd_pstate_ut_cases); 302 303 for (i = 0; i < arr_size; i++) { 304 amd_pstate_ut_cases[i].func(i); 305 switch (amd_pstate_ut_cases[i].result) { 306 case AMD_PSTATE_UT_RESULT_PASS: 307 pr_info("%-4d %-20s\t success!\n", i+1, amd_pstate_ut_cases[i].name); 308 break; 309 case AMD_PSTATE_UT_RESULT_FAIL: 310 default: 311 pr_info("%-4d %-20s\t fail!\n", i+1, amd_pstate_ut_cases[i].name); 312 break; 313 } 314 } 315 316 return 0; 317 } 318 319 static void __exit amd_pstate_ut_exit(void) 320 { 321 } 322 323 module_init(amd_pstate_ut_init); 324 module_exit(amd_pstate_ut_exit); 325 326 MODULE_AUTHOR("Meng Li <li.meng@amd.com>"); 327 MODULE_DESCRIPTION("AMD P-state driver Test module"); 328 MODULE_LICENSE("GPL"); 329