Re: [PATCH 13/19] cpupower: add the function to check amd-pstate enabled
From: Shuah Khan <skhan@linuxfoundation.org>
Date: 2021-09-09 22:16:29
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lkml
On 9/8/21 8:59 AM, Huang Rui wrote:
Introduce the cpupower_amd_pstate_enabled() to check whether the kernel mode enables amd-pstate.
What does "kernel mode" mean? Are you referring to kernel vs. firmware mode?
quoted hunk ↗ jump to hunk
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