[PATCH 2/3] cpupower: Introduce a new unit test module for AMD P-State driver

[Meng Li]

amd-pstate-ut is a kernel module for testing the functions of AMD P-State driver.

It can verify the required conditions and basic functions of AMD P-State
driver before integration test.

Signed-off-by: Meng Li <li.meng@xxxxxxx>
---
 tools/power/cpupower/debug/kernel/Makefile    |  10 +-
 .../cpupower/debug/kernel/amd-pstate-ut.c     | 618 ++++++++++++++++++
 2 files changed, 627 insertions(+), 1 deletion(-)
 create mode 100644 tools/power/cpupower/debug/kernel/amd-pstate-ut.c

diff --git a/tools/power/cpupower/debug/kernel/Makefile b/tools/power/cpupower/debug/kernel/Makefile
index 7b5c43684be1..314827f106b4 100644
--- a/tools/power/cpupower/debug/kernel/Makefile
+++ b/tools/power/cpupower/debug/kernel/Makefile
@@ -8,11 +8,19 @@ ifeq ("$(CONFIG_X86_TSC)", "y")
   obj-m	 += cpufreq-test_tsc.o
 endif
 
+amd_pstate_ut-y := amd-pstate-ut.o
+
+ifeq ("$(CONFIG_X86_AMD_PSTATE)", "y")
+  obj-m	 += amd_pstate_ut.o
+else ifeq ("$(CONFIG_X86_AMD_PSTATE)", "m")
+  obj-m	 += amd_pstate_ut.o
+endif
+
 default:
 	$(MAKE) -C $(KDIR) M=$(CURDIR)
 
 clean:
-	- rm -rf *.o *.ko .*.cmd .*.mod.* *.mod.c
+	- rm -rf *.o *.ko .*.cmd *.mod .*.mod.* *.mod.c
 	- rm -rf Module.symvers modules.order
 
 install: default
diff --git a/tools/power/cpupower/debug/kernel/amd-pstate-ut.c b/tools/power/cpupower/debug/kernel/amd-pstate-ut.c
new file mode 100644
index 000000000000..0cb08e50947b
--- /dev/null
+++ b/tools/power/cpupower/debug/kernel/amd-pstate-ut.c
@@ -0,0 +1,618 @@
+// SPDX-License-Identifier: GPL-1.0-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@xxxxxxx>
+ *
+ */
+
+#define pr_fmt(fmt) "AMD P-state UT: " 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>
+
+#define AMD_PSTATE_UT_ERR(...) pr_err(__VA_ARGS__)
+#define AMD_PSTATE_UT_DEBUG(...) pr_debug(__VA_ARGS__)
+#define AMD_PSTATE_UT_INFO(...) pr_info(__VA_ARGS__)
+
+#define UT_LOG_BEGIN(index) AMD_PSTATE_UT_DEBUG("****** Begin %-5d\t %-20s\t ******\n", index, ut_cases[index].name)
+#define UT_LOG_END(index) AMD_PSTATE_UT_DEBUG("****** End   %-5d\t %-20s\t ******\n", index, ut_cases[index].name)
+
+enum ut_index {
+	UT_INDEX_BEGIN=0,
+	UT_INDEX_END,
+	MAX_UT_INDEX,
+};
+
+enum ut_result {
+	UT_RESULT_NOT_TEST=0,	//' '
+	UT_RESULT_PASS,		//'P'
+	UT_RESULT_FAIL,		//'F'
+	MAX_UT_RESULT,
+};
+
+struct ut_struct {
+	const char *name;
+	void (*func)(u32 index);
+	u32 index;
+	enum ut_result result;
+};
+
+static enum ut_result ut_special(u32 begin_index,
+		u32 end_index);
+
+static void ut_stop(u32 index);
+static void ut_all(u32 index);
+static void ut_x86_vendor(u32 index);
+static void ut_acpi_cpc(u32 index);
+static void ut_modprobed_driver(u32 index);
+static void ut_capability_check(u32 index);
+static void ut_enable(u32 index);
+static void ut_init_perf(u32 index);
+static void ut_support_boost(u32 index);
+static void ut_clear_status(u32 index);
+
+/* Amd-pstate unit test cases
+ * 0 : stop
+ * 1 : all
+ * n : from n to start
+ */
+static u32 ut_array_index[MAX_UT_INDEX] = {0};
+
+static struct ut_struct ut_cases[] = {
+	{"stop",                ut_stop                }, //0
+	{"all",                 ut_all                 }, //1
+	{"x86_vendor",          ut_x86_vendor          },
+	{"acpi_cpc_valid",      ut_acpi_cpc            },
+	{"modprobed_driver",    ut_modprobed_driver    },
+	{"capability_check",    ut_capability_check    },
+	{"enable",              ut_enable              },
+	{"init_perf",           ut_init_perf           },
+	{"support_boost",       ut_support_boost       },
+	{"clear_status",        ut_clear_status        } //max
+};
+
+static bool get_shared_mem(void)
+{
+	bool result = false;
+	char buf[5] = {0};
+	struct file *filp = NULL;
+	loff_t pos = 0;
+	ssize_t ret;
+
+	filp = filp_open("/sys/module/amd_pstate/parameters/shared_mem", FMODE_PREAD, 0);
+	if (IS_ERR(filp))
+	{
+		AMD_PSTATE_UT_ERR("%s Open param file fail!", __func__);
+	}
+	else
+	{
+		ret = kernel_read(filp, &buf, sizeof(buf), &pos);
+		if (ret < 0)
+		{
+			AMD_PSTATE_UT_ERR("%s ret=%ld unable to read from param file!", __func__, ret);
+		}
+	}
+	filp_close(filp, NULL);
+
+	if ('Y' == *buf)
+	{
+		result = true;
+	}
+
+	return (result);
+}
+
+static bool ut_check_index(u32 index,
+		const char *func_name)
+{
+	bool ret = true;
+
+	if (index != ut_cases[index].index)
+	{
+		AMD_PSTATE_UT_ERR("%s index=%d is error!", func_name, index);
+		ret = false;
+	}
+
+	return (ret);
+}
+
+static void ut_stop(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	AMD_PSTATE_UT_DEBUG("!====! Stop unit test! !====! \n");
+
+	//memset begin/end index
+	memset(ut_array_index, 0, sizeof(ut_array_index));
+}
+
+static void ut_all(u32 index)
+{
+	u32 arr_size = ARRAY_SIZE(ut_cases);
+	enum ut_result result = UT_RESULT_PASS;
+
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	if (index+1 < arr_size)
+	{
+		AMD_PSTATE_UT_DEBUG("!====! Begin all unit test! !====!\n");
+
+		//Not include ut_clear_status
+		result = ut_special(index+1, arr_size-1-1);
+
+		AMD_PSTATE_UT_DEBUG("!====! End   all unit test! !====!\n");
+	}
+	else
+	{
+		result = UT_RESULT_FAIL;
+		AMD_PSTATE_UT_ERR("%s arr_size=%d is error!", __func__, arr_size);
+	}
+	ut_cases[index].result = result;
+}
+
+static enum ut_result ut_special(u32 begin_index,
+		u32 end_index)
+{
+	u32 i = 0;
+	enum ut_result result = UT_RESULT_PASS;
+
+	for (i=begin_index; i<=end_index; i++)
+	{
+		if ((0 == ut_array_index[UT_INDEX_BEGIN]) &&
+			(0 == ut_array_index[UT_INDEX_END]))
+		{
+			AMD_PSTATE_UT_DEBUG("!====! Stop unit test : End %-5d\t %-20s\t! !====! \n", i, ut_cases[i].name);
+			break;
+		}
+		else
+		{
+			ut_cases[i].func(i);
+			if (UT_RESULT_PASS != ut_cases[i].result)
+			{
+				result = ut_cases[i].result;
+			}
+		}
+	}
+
+	return (result);
+}
+
+static void ut_x86_vendor(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+	{
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		ut_cases[index].result = UT_RESULT_FAIL;
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_acpi_cpc(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	if (acpi_cpc_valid())
+	{
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		ut_cases[index].result = UT_RESULT_FAIL;
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_modprobed_driver(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	if (cpufreq_get_current_driver())
+	{
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		ut_cases[index].result = UT_RESULT_FAIL;
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_capability_check(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	if (boot_cpu_has(X86_FEATURE_CPPC))
+	{
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		//shared memory
+		if (get_shared_mem())
+		{
+			ut_cases[index].result = UT_RESULT_PASS;
+		}
+		else
+		{
+			ut_cases[index].result = UT_RESULT_FAIL;
+		}
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_pstate_enable(u32 index)
+{
+	int ret = 0;
+	u64 cppc_enable = 0;
+
+	ret = rdmsrl_safe(MSR_AMD_CPPC_ENABLE, &cppc_enable);
+	if (ret)
+	{
+		ut_cases[index].result = UT_RESULT_FAIL;
+		AMD_PSTATE_UT_ERR("%s rdmsrl_safe MSR_AMD_CPPC_ENABLE ret=%d is error!", __func__, ret);
+		return;
+	}
+	if (cppc_enable)
+	{
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		ut_cases[index].result = UT_RESULT_FAIL;
+	}
+}
+
+static void ut_enable(u32 index)
+{
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	if (get_shared_mem())
+	{
+		//not check
+		ut_cases[index].result = UT_RESULT_PASS;
+	}
+	else
+	{
+		ut_pstate_enable(index);
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_init_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;
+
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	//get perf
+	highest_perf = amd_get_highest_perf();
+
+	for_each_possible_cpu(cpu)
+	{
+		//get amd cpudata
+		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)
+			{
+				ut_cases[index].result = UT_RESULT_FAIL;
+				AMD_PSTATE_UT_ERR("%s cppc_get_perf_caps ret=%d is error!", __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)
+			{
+				ut_cases[index].result = UT_RESULT_FAIL;
+				AMD_PSTATE_UT_ERR("%s rdmsrl_safe_on_cpu MSR_AMD_CPPC_CAP1 ret=%d is error!", __func__, ret);
+				return;
+			}
+
+			//get perf from MSR
+			nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1);
+			lowest_nonlinear_perf = AMD_CPPC_LOWNONLIN_PERF(cap1);
+			lowest_perf = AMD_CPPC_LOWEST_PERF(cap1);
+		}
+
+		//check highest_perf,nominal_perf,lowest_nonlinear_perf
+		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)))
+		{
+			ut_cases[index].result = UT_RESULT_FAIL;
+			AMD_PSTATE_UT_ERR("%s cpu%d highest_perf=%d %d nominal_perf=%d %d lowest_nonlinear_perf=%d %d lowest_perf=%d %d are not equal!",
+					__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;
+		}
+	}
+
+	ut_cases[index].result = UT_RESULT_PASS;
+
+	UT_LOG_END(index);
+}
+
+static void ut_support_boost(u32 index)
+{
+	int cpu = 0;
+	struct cpufreq_policy *policy = NULL;
+        struct amd_cpudata *cpudata = NULL;
+
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	for_each_possible_cpu(cpu)
+	{
+		//get amd cpudata
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy)
+			break;
+		cpudata = policy->driver_data;
+
+		if (READ_ONCE(cpudata->boost_supported))
+		{
+			ut_cases[index].result = UT_RESULT_PASS;
+		}
+		else
+		{
+			ut_cases[index].result = UT_RESULT_FAIL;
+			break;
+		}
+	}
+
+	UT_LOG_END(index);
+}
+
+static void ut_clear_status(u32 index)
+{
+	int i = 0;
+
+	if (!ut_check_index(index, __func__))
+	{
+		return;
+	}
+
+	UT_LOG_BEGIN(index);
+
+	for (i = 0; i < ARRAY_SIZE(ut_cases); i++)
+	{
+		ut_cases[i].result = UT_RESULT_NOT_TEST;
+	}
+
+	//memset begin/end index
+	memset(ut_array_index, 0, sizeof(ut_array_index));
+
+	UT_LOG_END(index);
+}
+
+static int param_set_index(const char *str)
+{
+	int i = 0, result = 0;
+
+	//memset begin/end index
+	memset(ut_array_index, 0, sizeof(ut_array_index));
+
+	//get begin/end index
+	while ((NULL != str) && ('\0' != *str) && ('\n' != *str))
+	{
+		ut_array_index[i] = ut_array_index[i]*10 + *str - '0';
+		str++;
+		if (' ' == *str)
+		{
+			str++;
+			i++;
+			if (MAX_UT_INDEX <= i)
+			{
+				result = -EINVAL;
+				AMD_PSTATE_UT_ERR("%s arg_num=%d, Invalid argument! \n", __func__, i);
+				break;
+			}
+		}
+	}
+
+	AMD_PSTATE_UT_DEBUG("%s %d %d result=%d! \n", __func__, ut_array_index[0], ut_array_index[1], result);
+
+	return (result);
+}
+
+static void ut_init_index(void)
+{
+	int i = 0;
+
+	if (1 != ut_cases[1].index)
+	{
+		//init all unit test cases index
+		for (i = 0; i < ARRAY_SIZE(ut_cases); i++)
+		{
+			ut_cases[i].index = i;
+		}
+	}
+}
+
+/* Parameters */
+static int param_set_unit_test(const char *buffer,
+		const struct kernel_param *kp)
+{
+	int result = 0;
+	u32 begin_index = 0, end_index = 0;
+
+	//init test case index
+	ut_init_index();
+
+	//get begin/end index
+	result = param_set_index(buffer);
+	if (result < 0)
+		return result;
+
+	begin_index  = ut_array_index[UT_INDEX_BEGIN];
+	end_index  = ut_array_index[UT_INDEX_END];
+	if (0 == begin_index)
+	{
+		ut_array_index[UT_INDEX_END] = 0;
+		ut_stop(0);
+	}
+	else if (1 == begin_index)
+	{
+		//Not include ut_clear_status
+		ut_array_index[UT_INDEX_END] = ARRAY_SIZE(ut_cases) - 1 - 1;
+		ut_all(1);
+	}
+	else
+	{
+		if (begin_index > end_index)
+		{
+			end_index = begin_index;
+			ut_array_index[UT_INDEX_END] = end_index;
+		}
+		ut_special(begin_index, end_index);
+	}
+
+	return result;
+};
+
+static int param_get_unit_test(char *buffer,
+		const struct kernel_param *kp)
+{
+	char ret = 'N';
+	int i = 0, result = 0;
+
+	result = sprintf(buffer, "%-5s\t %-20s\t Status\n", "Index", "Test cases");
+
+	for (i = 0; i < ARRAY_SIZE(ut_cases); i++)
+	{
+		switch (ut_cases[i].result)
+		{
+		case UT_RESULT_NOT_TEST:
+			ret = ' ';
+			break;
+
+		case UT_RESULT_PASS:
+			ret = 'P';
+			break;
+
+		case UT_RESULT_FAIL:
+			ret = 'F';
+			break;
+
+		default:
+			ret = ' ';
+			break;
+		}
+
+		result += sprintf(buffer + result, "%-5d\t %-20s\t [%c]\n",
+				ut_cases[i].index,
+				ut_cases[i].name,
+				ret);
+	}
+
+	result += sprintf(buffer + result, "------------------------------------------\nbegin_index = %d end_index= %d\n",
+			ut_array_index[UT_INDEX_BEGIN], ut_array_index[UT_INDEX_END]);
+
+	return result;
+};
+
+static const struct kernel_param_ops param_ops_unittest = {
+	.set = param_set_unit_test,
+	.get = param_get_unit_test,
+};
+
+module_param_cb(unit_test, &param_ops_unittest, &ut_array_index, 0664);
+MODULE_PARM_DESC(unit_test,
+		" AMD P-state unit test 0 : stop 1 : start all x: start from x");
+
+/* Module */
+static int __init amd_pstate_ut_init(void)
+{
+	//init test case index
+	ut_init_index();
+
+	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@xxxxxxx>");
+MODULE_DESCRIPTION("Unit test for AMD P-state driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1