// SPDX-License-Identifier: GPL-2.0-or-later /* * AMD Processor P-state Frequency Driver Unit Test * * Copyright (C) 2022 Advanced Micro Devices, Inc. All Rights Reserved. * * Author: Meng Li <li.meng@amd.com> * * The AMD P-State Unit Test is a test module for testing the amd-pstate * driver. 1) It can help all users to verify their processor support * (SBIOS/Firmware or Hardware). 2) Kernel can have a basic function * test to avoid the kernel regression during the update. 3) We can * introduce more functional or performance tests to align the result * together, it will benefit power and performance scale optimization. * * This driver implements basic framework with plans to enhance it with * additional test cases to improve the depth and coverage of the test. * * See Documentation/admin-guide/pm/amd-pstate.rst Unit Tests for * amd-pstate to get more detail. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/kernel.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/fs.h> #include <linux/amd-pstate.h> #include <acpi/cppc_acpi.h> /* * Abbreviations: * amd_pstate_ut: used as a shortform for AMD P-State unit test. * It helps to keep variable names smaller, simpler */ enum amd_pstate_ut_result { AMD_PSTATE_UT_RESULT_PASS, AMD_PSTATE_UT_RESULT_FAIL, }; struct amd_pstate_ut_struct { const char *name; void (*func)(u32 index); enum amd_pstate_ut_result result; }; /* * Kernel module for testing the AMD P-State unit test */ static void amd_pstate_ut_acpi_cpc_valid(u32 index); static void amd_pstate_ut_check_enabled(u32 index); static void amd_pstate_ut_check_perf(u32 index); static void amd_pstate_ut_check_freq(u32 index); static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = { {"amd_pstate_ut_acpi_cpc_valid", amd_pstate_ut_acpi_cpc_valid }, {"amd_pstate_ut_check_enabled", amd_pstate_ut_check_enabled }, {"amd_pstate_ut_check_perf", amd_pstate_ut_check_perf }, {"amd_pstate_ut_check_freq", amd_pstate_ut_check_freq } }; static bool get_shared_mem(void) { bool result = false; char path[] = "/sys/module/amd_pstate/parameters/shared_mem"; char buf[5] = {0}; struct file *filp = NULL; loff_t pos = 0; ssize_t ret; if (!boot_cpu_has(X86_FEATURE_CPPC)) { filp = filp_open(path, O_RDONLY, 0); if (IS_ERR(filp)) pr_err("%s unable to open %s file!\n", __func__, path); else { ret = kernel_read(filp, &buf, sizeof(buf), &pos); if (ret < 0) pr_err("%s read %s file fail ret=%ld!\n", __func__, path, (long)ret); filp_close(filp, NULL); } if ('Y' == *buf) result = true; } return result; } /* * check the _CPC object is present in SBIOS. */ static void amd_pstate_ut_acpi_cpc_valid(u32 index) { if (acpi_cpc_valid()) amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; else { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s the _CPC object is not present in SBIOS!\n", __func__); } } static void amd_pstate_ut_pstate_enable(u32 index) { int ret = 0; u64 cppc_enable = 0; ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable); if (ret) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d error!\n", __func__, ret); return; } if (cppc_enable) amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; else { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s amd pstate must be enabled!\n", __func__); } } /* * check if amd pstate is enabled */ static void amd_pstate_ut_check_enabled(u32 index) { if (get_shared_mem()) amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; else amd_pstate_ut_pstate_enable(index); } /* * check if performance values are reasonable. * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0 */ static void amd_pstate_ut_check_perf(u32 index) { int cpu = 0, ret = 0; u32 highest_perf = 0, nominal_perf = 0, lowest_nonlinear_perf = 0, lowest_perf = 0; u64 cap1 = 0; struct cppc_perf_caps cppc_perf; struct cpufreq_policy *policy = NULL; struct amd_cpudata *cpudata = NULL; highest_perf = amd_get_highest_perf(); for_each_possible_cpu(cpu) { policy = cpufreq_cpu_get(cpu); if (!policy) break; cpudata = policy->driver_data; if (get_shared_mem()) { ret = cppc_get_perf_caps(cpu, &cppc_perf); if (ret) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret); return; } nominal_perf = cppc_perf.nominal_perf; lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; lowest_perf = cppc_perf.lowest_perf; } else { ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1); if (ret) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret); return; } nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1); lowest_nonlinear_perf = AMD_CPPC_LOWNONLIN_PERF(cap1); lowest_perf = AMD_CPPC_LOWEST_PERF(cap1); } if ((highest_perf != READ_ONCE(cpudata->highest_perf)) || (nominal_perf != READ_ONCE(cpudata->nominal_perf)) || (lowest_nonlinear_perf != READ_ONCE(cpudata->lowest_nonlinear_perf)) || (lowest_perf != READ_ONCE(cpudata->lowest_perf))) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d highest=%d %d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d, they should be equal!\n", __func__, cpu, highest_perf, cpudata->highest_perf, nominal_perf, cpudata->nominal_perf, lowest_nonlinear_perf, cpudata->lowest_nonlinear_perf, lowest_perf, cpudata->lowest_perf); return; } if (!((highest_perf >= nominal_perf) && (nominal_perf > lowest_nonlinear_perf) && (lowest_nonlinear_perf > lowest_perf) && (lowest_perf > 0))) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d highest=%d >= nominal=%d > lowest_nonlinear=%d > lowest=%d > 0, the formula is incorrect!\n", __func__, cpu, highest_perf, nominal_perf, lowest_nonlinear_perf, lowest_perf); return; } } amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; } /* * Check if frequency values are reasonable. * max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 * check max freq when set support boost mode. */ static void amd_pstate_ut_check_freq(u32 index) { int cpu = 0; struct cpufreq_policy *policy = NULL; struct amd_cpudata *cpudata = NULL; for_each_possible_cpu(cpu) { policy = cpufreq_cpu_get(cpu); if (!policy) break; cpudata = policy->driver_data; if (!((cpudata->max_freq >= cpudata->nominal_freq) && (cpudata->nominal_freq > cpudata->lowest_nonlinear_freq) && (cpudata->lowest_nonlinear_freq > cpudata->min_freq) && (cpudata->min_freq > 0))) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n", __func__, cpu, cpudata->max_freq, cpudata->nominal_freq, cpudata->lowest_nonlinear_freq, cpudata->min_freq); return; } if (cpudata->min_freq != policy->min) { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d, they should be equal!\n", __func__, cpu, cpudata->min_freq, policy->min); return; } if (cpudata->boost_supported) { if ((policy->max == cpudata->max_freq) || (policy->max == cpudata->nominal_freq)) amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; else { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n", __func__, cpu, policy->max, cpudata->max_freq, cpudata->nominal_freq); return; } } else { amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL; pr_err("%s cpu%d must support boost!\n", __func__, cpu); return; } } amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS; } static int __init amd_pstate_ut_init(void) { u32 i = 0, arr_size = ARRAY_SIZE(amd_pstate_ut_cases); for (i = 0; i < arr_size; i++) { amd_pstate_ut_cases[i].func(i); switch (amd_pstate_ut_cases[i].result) { case AMD_PSTATE_UT_RESULT_PASS: pr_info("%-4d %-20s\t success!\n", i+1, amd_pstate_ut_cases[i].name); break; case AMD_PSTATE_UT_RESULT_FAIL: default: pr_info("%-4d %-20s\t fail!\n", i+1, amd_pstate_ut_cases[i].name); break; } } return 0; } static void __exit amd_pstate_ut_exit(void) { } module_init(amd_pstate_ut_init); module_exit(amd_pstate_ut_exit); MODULE_AUTHOR("Meng Li <li.meng@amd.com>"); MODULE_DESCRIPTION("AMD P-state driver Test module"); MODULE_LICENSE("GPL");