RE: [PATCH v3 4/5] cpupower: Add support for amd_pstate mode change

["Yuan, Perry" <Perry.Yuan@amd.com>]

[AMD Official Use Only - General]

> -----Original Message-----
> From: Karny, Wyes <Wyes.Karny@amd.com>
> Sent: Tuesday, June 20, 2023 3:05 AM
> To: trenn@suse.com; shuah@kernel.org
> Cc: linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org; rafael@kernel.org;
> Shenoy, Gautham Ranjal <gautham.shenoy@amd.com>; Limonciello, Mario
> <Mario.Limonciello@amd.com>; Huang, Ray <Ray.Huang@amd.com>; Yuan,
> Perry <Perry.Yuan@amd.com>; Karny, Wyes <Wyes.Karny@amd.com>; Huang,
> Ray <Ray.Huang@amd.com>; Limonciello, Mario
> <Mario.Limonciello@amd.com>
> Subject: [PATCH v3 4/5] cpupower: Add support for amd_pstate mode change
>
> amd_pstate supports changing of its mode dynamically via `status` sysfs file.
> Add the same capability in cpupower. To change the mode to active mode use
> below command:
>
> cpupower set --amd-pstate-mode active
>
> Acked-by: Huang Rui <ray.huang@amd.com>
> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> Signed-off-by: Wyes Karny <wyes.karny@amd.com>
> ---
>  tools/power/cpupower/utils/cpupower-set.c    | 24 ++++++++++++++++++--
>  tools/power/cpupower/utils/helpers/helpers.h |  3 +++
>  tools/power/cpupower/utils/helpers/misc.c    | 18 +++++++++++++++
>  3 files changed, 43 insertions(+), 2 deletions(-)
>
> diff --git a/tools/power/cpupower/utils/cpupower-set.c
> b/tools/power/cpupower/utils/cpupower-set.c
> index a789b123dbd4..c2ba69b7ea54 100644
> --- a/tools/power/cpupower/utils/cpupower-set.c
> +++ b/tools/power/cpupower/utils/cpupower-set.c
> @@ -19,6 +19,7 @@
>  static struct option set_opts[] = {
>       {"perf-bias", required_argument, NULL, 'b'},
>       {"epp", required_argument, NULL, 'e'},
> +     {"amd-pstate-mode", required_argument, NULL, 'm'},
>       { },
>  };
>
> @@ -39,12 +40,13 @@ int cmd_set(int argc, char **argv)
>               struct {
>                       int perf_bias:1;
>                       int epp:1;
> +                     int mode:1;
>               };
>               int params;
>       } params;
>       int perf_bias = 0;
>       int ret = 0;
> -     char epp[30];
> +     char epp[30], mode[20];
>
>       ret = uname(&uts);
>       if (!ret && (!strcmp(uts.machine, "ppc64le") || @@ -58,7 +60,7 @@
> int cmd_set(int argc, char **argv)
>
>       params.params = 0;
>       /* parameter parsing */
> -     while ((ret = getopt_long(argc, argv, "b:e:",
> +     while ((ret = getopt_long(argc, argv, "b:e:m:",
>                                               set_opts, NULL)) != -1) {
>               switch (ret) {
>               case 'b':
> @@ -81,6 +83,17 @@ int cmd_set(int argc, char **argv)
>                       }
>                       params.epp = 1;
>                       break;
> +             case 'm':
> +                     if (cpupower_cpu_info.vendor != X86_VENDOR_AMD)
> +                             print_wrong_arg_exit();
> +                     if (params.mode)
> +                             print_wrong_arg_exit();
> +                     if (sscanf(optarg, "%19s", mode) != 1) {
> +                             print_wrong_arg_exit();
> +                             return -EINVAL;
> +                     }
> +                     params.mode = 1;
> +                     break;
>               default:
>                       print_wrong_arg_exit();
>               }
> @@ -89,6 +102,12 @@ int cmd_set(int argc, char **argv)
>       if (!params.params)
>               print_wrong_arg_exit();
>
> +     if (params.mode) {
> +             ret = cpupower_set_amd_pstate_mode(mode);
> +             if (ret)
> +                     fprintf(stderr, "Error setting mode\n");
> +     }
> +
>       /* Default is: set all CPUs */
>       if (bitmask_isallclear(cpus_chosen))
>               bitmask_setall(cpus_chosen);
> @@ -123,6 +142,7 @@ int cmd_set(int argc, char **argv)
>                               break;
>                       }
>               }
> +
>       }
>       return ret;
>  }
> diff --git a/tools/power/cpupower/utils/helpers/helpers.h
> b/tools/power/cpupower/utils/helpers/helpers.h
> index 5d998de2d291..d35596631eef 100644
> --- a/tools/power/cpupower/utils/helpers/helpers.h
> +++ b/tools/power/cpupower/utils/helpers/helpers.h
> @@ -117,6 +117,7 @@ extern int cpupower_intel_get_perf_bias(unsigned int
> cpu);  extern unsigned long long msr_intel_get_turbo_ratio(unsigned int cpu);
>
>  extern int cpupower_set_epp(unsigned int cpu, char *epp);
> +extern int cpupower_set_amd_pstate_mode(char *mode);
>
>  /* Read/Write msr ****************************/
>
> @@ -177,6 +178,8 @@ static inline unsigned long long
> msr_intel_get_turbo_ratio(unsigned int cpu)
>
>  static inline int cpupower_set_epp(unsigned int cpu, char *epp)  { return -1; };
> +static inline int cpupower_set_amd_pstate_mode(char *mode) { return -1;
> +};
>
>  /* Read/Write msr ****************************/
>
> diff --git a/tools/power/cpupower/utils/helpers/misc.c
> b/tools/power/cpupower/utils/helpers/misc.c
> index 583df38ab13c..075c136a100c 100644
> --- a/tools/power/cpupower/utils/helpers/misc.c
> +++ b/tools/power/cpupower/utils/helpers/misc.c
> @@ -106,6 +106,24 @@ int cpupower_set_epp(unsigned int cpu, char *epp)
>       return 0;
>  }
>
> +int cpupower_set_amd_pstate_mode(char *mode) {
> +     char path[SYSFS_PATH_MAX];
> +     char linebuf[20] = {};
> +
> +     snprintf(path, sizeof(path), PATH_TO_CPU "amd_pstate/status");
> +
> +     if (!is_valid_path(path))
> +             return -1;
> +
> +     snprintf(linebuf, sizeof(linebuf), "%s\n", mode);
> +
> +     if (cpupower_write_sysfs(path, linebuf, 20) <= 0)
> +             return -1;
> +
> +     return 0;
> +}
> +
>  bool cpupower_amd_pstate_enabled(void)
>  {
>       char *driver = cpufreq_get_driver(0);
> --
> 2.34.1

Tested-by: Perry Yuan <Perry.Yuan@amd.com>