[PATCH 13/19] cpupower: add the function to check amd-pstate enabled

From: Huang Rui <ray.huang@amd.com>
To: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Shuah Khan <skhan@linuxfoundation.org>,
	"Borislav Petkov" <bp@suse.de>, Ingo Molnar <mingo@kernel.org>,
	<linux-pm@vger.kernel.org>
Cc: Deepak Sharma <deepak.sharma@amd.com>,
	Alex Deucher <alexander.deucher@amd.com>,
	Mario Limonciello <mario.limonciello@amd.com>,
	Nathan Fontenot <nathan.fontenot@amd.com>,
	Jinzhou Su <Jinzhou.Su@amd.com>,
	Xiaojian Du <Xiaojian.Du@amd.com>, <linux-kernel@vger.kernel.org>,
	<x86@kernel.org>, Huang Rui <ray.huang@amd.com>
Subject: [PATCH 13/19] cpupower: add the function to check amd-pstate enabled
Date: Wed, 8 Sep 2021 22:59:55 +0800	[thread overview]
Message-ID: <20210908150001.3702552-14-ray.huang@amd.com> (raw)
In-Reply-To: <20210908150001.3702552-1-ray.huang@amd.com>

Introduce the cpupower_amd_pstate_enabled() to check whether the kernel
mode enables amd-pstate.

Signed-off-by: Huang Rui <ray.huang@amd.com>
---
 tools/power/cpupower/utils/helpers/helpers.h |  5 +++++
 tools/power/cpupower/utils/helpers/misc.c    | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/tools/power/cpupower/utils/helpers/helpers.h b/tools/power/cpupower/utils/helpers/helpers.h
index b4813efdfb00..eb43c14d1728 100644
--- a/tools/power/cpupower/utils/helpers/helpers.h
+++ b/tools/power/cpupower/utils/helpers/helpers.h
@@ -136,6 +136,11 @@ extern int decode_pstates(unsigned int cpu, int boost_states,
 
 extern int cpufreq_has_boost_support(unsigned int cpu, int *support,
 				     int *active, int * states);
+
+/* AMD PSTATE enabling **************************/
+
+extern unsigned long cpupower_amd_pstate_enabled(unsigned int cpu);
+
 /*
  * CPUID functions returning a single datum
  */
diff --git a/tools/power/cpupower/utils/helpers/misc.c b/tools/power/cpupower/utils/helpers/misc.c
index fc6e34511721..07d80775fb68 100644
--- a/tools/power/cpupower/utils/helpers/misc.c
+++ b/tools/power/cpupower/utils/helpers/misc.c
@@ -83,6 +83,26 @@ int cpupower_intel_set_perf_bias(unsigned int cpu, unsigned int val)
 	return 0;
 }
 
+unsigned long cpupower_amd_pstate_enabled(unsigned int cpu)
+{
+	char linebuf[MAX_LINE_LEN];
+	char path[SYSFS_PATH_MAX];
+	unsigned long val;
+	char *endp;
+
+	snprintf(path, sizeof(path),
+		 PATH_TO_CPU "cpu%u/cpufreq/is_amd_pstate_enabled", cpu);
+
+	if (cpupower_read_sysfs(path, linebuf, MAX_LINE_LEN) == 0)
+		return 0;
+
+	val = strtoul(linebuf, &endp, 0);
+	if (endp == linebuf || errno == ERANGE)
+		return 0;
+
+	return val;
+}
+
 #endif /* #if defined(__i386__) || defined(__x86_64__) */
 
 /* get_cpustate
-- 
2.25.1

