1 files changed, 298 insertions, 0 deletions
diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c
new file mode 100644
index 000000000000..447b9aa5ce40
--- /dev/null
+++ b/drivers/cpufreq/amd-pstate-ut.c
@@ -0,0 +1,298 @@
+// 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/bitfield.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/fs.h>
+#include <linux/cleanup.h>
+
+#include <acpi/cppc_acpi.h>
+
+#include <asm/msr.h>
+
+#include "amd-pstate.h"
+
+
+struct amd_pstate_ut_struct {
+	const char *name;
+	int (*func)(u32 index);
+};
+
+/*
+ * Kernel module for testing the AMD P-State unit test
+ */
+static int amd_pstate_ut_acpi_cpc_valid(u32 index);
+static int amd_pstate_ut_check_enabled(u32 index);
+static int amd_pstate_ut_check_perf(u32 index);
+static int amd_pstate_ut_check_freq(u32 index);
+static int amd_pstate_ut_check_driver(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       },
+	{"amd_pstate_ut_check_driver",	   amd_pstate_ut_check_driver     }
+};
+
+static bool get_shared_mem(void)
+{
+	bool result = false;
+
+	if (!boot_cpu_has(X86_FEATURE_CPPC))
+		result = true;
+
+	return result;
+}
+
+/*
+ * check the _CPC object is present in SBIOS.
+ */
+static int amd_pstate_ut_acpi_cpc_valid(u32 index)
+{
+	if (!acpi_cpc_valid()) {
+		pr_err("%s the _CPC object is not present in SBIOS!\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * check if amd pstate is enabled
+ */
+static int amd_pstate_ut_check_enabled(u32 index)
+{
+	u64 cppc_enable = 0;
+	int ret;
+
+	if (get_shared_mem())
+		return 0;
+
+	ret = rdmsrq_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable);
+	if (ret) {
+		pr_err("%s rdmsrq_safe MSR_AMD_CPPC_ENABLE ret=%d error!\n", __func__, ret);
+		return ret;
+	}
+
+	if (!cppc_enable) {
+		pr_err("%s amd pstate must be enabled!\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * check if performance values are reasonable.
+ * highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0
+ */
+static int 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;
+	union perf_cached cur_perf;
+
+	for_each_online_cpu(cpu) {
+		struct cpufreq_policy *policy __free(put_cpufreq_policy) = NULL;
+		struct amd_cpudata *cpudata;
+
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			continue;
+		cpudata = policy->driver_data;
+
+		if (get_shared_mem()) {
+			ret = cppc_get_perf_caps(cpu, &cppc_perf);
+			if (ret) {
+				pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret);
+				return ret;
+			}
+
+			highest_perf = cppc_perf.highest_perf;
+			nominal_perf = cppc_perf.nominal_perf;
+			lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
+			lowest_perf = cppc_perf.lowest_perf;
+		} else {
+			ret = rdmsrq_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1);
+			if (ret) {
+				pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret);
+				return ret;
+			}
+
+			highest_perf = FIELD_GET(AMD_CPPC_HIGHEST_PERF_MASK, cap1);
+			nominal_perf = FIELD_GET(AMD_CPPC_NOMINAL_PERF_MASK, cap1);
+			lowest_nonlinear_perf = FIELD_GET(AMD_CPPC_LOWNONLIN_PERF_MASK, cap1);
+			lowest_perf = FIELD_GET(AMD_CPPC_LOWEST_PERF_MASK, cap1);
+		}
+
+		cur_perf = READ_ONCE(cpudata->perf);
+		if (highest_perf != cur_perf.highest_perf && !cpudata->hw_prefcore) {
+			pr_err("%s cpu%d highest=%d %d highest perf doesn't match\n",
+				__func__, cpu, highest_perf, cur_perf.highest_perf);
+			return -EINVAL;
+		}
+		if (nominal_perf != cur_perf.nominal_perf ||
+		   (lowest_nonlinear_perf != cur_perf.lowest_nonlinear_perf) ||
+		   (lowest_perf != cur_perf.lowest_perf)) {
+			pr_err("%s cpu%d nominal=%d %d lowest_nonlinear=%d %d lowest=%d %d, they should be equal!\n",
+				__func__, cpu, nominal_perf, cur_perf.nominal_perf,
+				lowest_nonlinear_perf, cur_perf.lowest_nonlinear_perf,
+				lowest_perf, cur_perf.lowest_perf);
+			return -EINVAL;
+		}
+
+		if (!((highest_perf >= nominal_perf) &&
+			(nominal_perf > lowest_nonlinear_perf) &&
+			(lowest_nonlinear_perf >= lowest_perf) &&
+			(lowest_perf > 0))) {
+			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 -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * 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 int amd_pstate_ut_check_freq(u32 index)
+{
+	int cpu = 0;
+
+	for_each_online_cpu(cpu) {
+		struct cpufreq_policy *policy __free(put_cpufreq_policy) = NULL;
+		struct amd_cpudata *cpudata;
+
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			continue;
+		cpudata = policy->driver_data;
+
+		if (!((policy->cpuinfo.max_freq >= cpudata->nominal_freq) &&
+			(cpudata->nominal_freq > cpudata->lowest_nonlinear_freq) &&
+			(cpudata->lowest_nonlinear_freq >= policy->cpuinfo.min_freq) &&
+			(policy->cpuinfo.min_freq > 0))) {
+			pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n",
+				__func__, cpu, policy->cpuinfo.max_freq, cpudata->nominal_freq,
+				cpudata->lowest_nonlinear_freq, policy->cpuinfo.min_freq);
+			return -EINVAL;
+		}
+
+		if (cpudata->lowest_nonlinear_freq != policy->min) {
+			pr_err("%s cpu%d cpudata_lowest_nonlinear_freq=%d policy_min=%d, they should be equal!\n",
+				__func__, cpu, cpudata->lowest_nonlinear_freq, policy->min);
+			return -EINVAL;
+		}
+
+		if (cpudata->boost_supported) {
+			if ((policy->max != policy->cpuinfo.max_freq) &&
+			    (policy->max != cpudata->nominal_freq)) {
+				pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n",
+					__func__, cpu, policy->max, policy->cpuinfo.max_freq,
+					cpudata->nominal_freq);
+				return -EINVAL;
+			}
+		} else {
+			pr_err("%s cpu%d must support boost!\n", __func__, cpu);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int amd_pstate_set_mode(enum amd_pstate_mode mode)
+{
+	const char *mode_str = amd_pstate_get_mode_string(mode);
+
+	pr_debug("->setting mode to %s\n", mode_str);
+
+	return amd_pstate_update_status(mode_str, strlen(mode_str));
+}
+
+static int amd_pstate_ut_check_driver(u32 index)
+{
+	enum amd_pstate_mode mode1, mode2 = AMD_PSTATE_DISABLE;
+	enum amd_pstate_mode orig_mode = amd_pstate_get_status();
+	int ret;
+
+	for (mode1 = AMD_PSTATE_DISABLE; mode1 < AMD_PSTATE_MAX; mode1++) {
+		ret = amd_pstate_set_mode(mode1);
+		if (ret)
+			return ret;
+		for (mode2 = AMD_PSTATE_DISABLE; mode2 < AMD_PSTATE_MAX; mode2++) {
+			if (mode1 == mode2)
+				continue;
+			ret = amd_pstate_set_mode(mode2);
+			if (ret)
+				goto out;
+		}
+	}
+
+out:
+	if (ret)
+		pr_warn("%s: failed to update status for %s->%s: %d\n", __func__,
+			amd_pstate_get_mode_string(mode1),
+			amd_pstate_get_mode_string(mode2), ret);
+
+	amd_pstate_set_mode(orig_mode);
+	return ret;
+}
+
+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++) {
+		int ret = amd_pstate_ut_cases[i].func(i);
+
+		if (ret)
+			pr_err("%-4d %-20s\t fail: %d!\n", i+1, amd_pstate_ut_cases[i].name, ret);
+		else
+			pr_info("%-4d %-20s\t success!\n", i+1, amd_pstate_ut_cases[i].name);
+	}
+
+	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");