cpupower: Add intel_pstate turbo boost support for Intel platforms

On modern Intel platforms, the intel_pstate driver is commonly used and
it provides turbo boost control via
/sys/devices/system/cpu/intel_pstate/no_turbo.

However, cpupower doesn't handle this. it
1. shows turbo boost as "active" blindly for Intel platforms
2. controls turbo boost functionality via the generic
   /sys/devices/system/cpu/cpufreq/boost sysfs interface only.

Enhance the cpupower tool to ensure the "--boost" command works
seamlessly on Intel platforms with intel_pstate driver running.

Without this patch,
   $ echo 1 | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo
   1
   $ sudo cpupower frequency-info --boost
   analyzing CPU 21:
     boost state support:
       Supported: yes
       Active: yes
   $ sudo cpupower set --boost 0
   Error setting turbo-boost
   $ sudo cpupower set --boost 1
   Error setting turbo-boost

With this patch,
   $ cat /sys/devices/system/cpu/intel_pstate/no_turbo
   0
   $ sudo cpupower set --boost 0
   $ sudo cpupower frequency-info --boost
   analyzing CPU 21:
     boost state support:
       Supported: yes
       Active: no
   $ cat /sys/devices/system/cpu/intel_pstate/no_turbo
   1
   $ sudo cpupower set --boost 1
   $ sudo cpupower frequency-info --boost
   analyzing CPU 28:
     boost state support:
       Supported: yes
       Active: yes
   $ cat /sys/devices/system/cpu/intel_pstate/no_turbo
   0

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

diff --git a/tools/power/cpupower/utils/cpupower-set.c b/tools/power/cpupower/utils/cpupower-set.c
index c2117e5650dd3f407c327d132aec62fcb5f96fab..550a942e72ce7d833bda04b94b88a913eb1f47e3 100644 (file)
--- a/tools/power/cpupower/utils/cpupower-set.c
+++ b/tools/power/cpupower/utils/cpupower-set.c
@@ -124,7 +124,11 @@ int cmd_set(int argc, char **argv)
        }
 
        if (params.turbo_boost) {
-               ret = cpupower_set_turbo_boost(turbo_boost);
+               if (cpupower_cpu_info.vendor == X86_VENDOR_INTEL)
+                       ret = cpupower_set_intel_turbo_boost(turbo_boost);
+               else
+                       ret = cpupower_set_generic_turbo_boost(turbo_boost);
+
                if (ret)
                        fprintf(stderr, "Error setting turbo-boost\n");
        }

diff --git a/tools/power/cpupower/utils/helpers/helpers.h b/tools/power/cpupower/utils/helpers/helpers.h
index 82ea62bdf5a26981f4df38a5cff4746d712c05c2..a3ad80b9c2c2b01c408d8a6e4ef3ef9d3efbb1a6 100644 (file)
--- a/tools/power/cpupower/utils/helpers/helpers.h
+++ b/tools/power/cpupower/utils/helpers/helpers.h
@@ -104,7 +104,7 @@ extern struct cpupower_cpu_info cpupower_cpu_info;
 /* cpuid and cpuinfo helpers  **************************/
 
 int cpufreq_has_generic_boost_support(bool *active);
-int cpupower_set_turbo_boost(int turbo_boost);
+int cpupower_set_generic_turbo_boost(int turbo_boost);
 
 /* X86 ONLY ****************************************/
 #if defined(__i386__) || defined(__x86_64__)
@@ -143,6 +143,7 @@ extern int decode_pstates(unsigned int cpu, int boost_states,
 
 int cpufreq_has_x86_boost_support(unsigned int cpu, int *support,
                                  int *active, int *states);
+int cpupower_set_intel_turbo_boost(int turbo_boost);
 
 /* AMD P-State stuff **************************/
 bool cpupower_amd_pstate_enabled(void);
@@ -189,6 +190,8 @@ static inline int cpupower_set_amd_pstate_mode(char *mode)
 static inline int cpufreq_has_x86_boost_support(unsigned int cpu, int *support,
                                                int *active, int *states)
 { return -1; }
+static inline int cpupower_set_intel_turbo_boost(int turbo_boost)
+{ return -1; }
 
 static inline bool cpupower_amd_pstate_enabled(void)
 { return false; }

diff --git a/tools/power/cpupower/utils/helpers/misc.c b/tools/power/cpupower/utils/helpers/misc.c
index 166dc1e470ea6d70079fea6570750885d549603a..eebfc79a48899c430635e883e5201969b10d0bef 100644 (file)
--- a/tools/power/cpupower/utils/helpers/misc.c
+++ b/tools/power/cpupower/utils/helpers/misc.c
@@ -19,6 +19,9 @@ int cpufreq_has_x86_boost_support(unsigned int cpu, int *support, int *active,
 {
        int ret;
        unsigned long long val;
+       char linebuf[MAX_LINE_LEN];
+       char path[SYSFS_PATH_MAX];
+       char *endp;
 
        *support = *active = *states = 0;
 
@@ -42,8 +45,42 @@ int cpufreq_has_x86_boost_support(unsigned int cpu, int *support, int *active,
                }
        } else if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_PSTATE) {
                amd_pstate_boost_init(cpu, support, active);
-       } else if (cpupower_cpu_info.caps & CPUPOWER_CAP_INTEL_IDA)
+       } else if (cpupower_cpu_info.caps & CPUPOWER_CAP_INTEL_IDA) {
                *support = *active = 1;
+
+               snprintf(path, sizeof(path), PATH_TO_CPU "intel_pstate/no_turbo");
+
+               if (!is_valid_path(path))
+                       return 0;
+
+               if (cpupower_read_sysfs(path, linebuf, MAX_LINE_LEN) == 0)
+                       return -1;
+
+               val = strtol(linebuf, &endp, 0);
+               if (endp == linebuf || errno == ERANGE)
+                       return -1;
+
+               *active = !val;
+       }
+       return 0;
+}
+
+int cpupower_set_intel_turbo_boost(int turbo_boost)
+{
+       char path[SYSFS_PATH_MAX];
+       char linebuf[2] = {};
+
+       snprintf(path, sizeof(path), PATH_TO_CPU "intel_pstate/no_turbo");
+
+       /* Fallback to generic solution when intel_pstate driver not running */
+       if (!is_valid_path(path))
+               return cpupower_set_generic_turbo_boost(turbo_boost);
+
+       snprintf(linebuf, sizeof(linebuf), "%d", !turbo_boost);
+
+       if (cpupower_write_sysfs(path, linebuf, 2) <= 0)
+               return -1;
+
        return 0;
 }
 
@@ -274,7 +311,7 @@ void print_speed(unsigned long speed, int no_rounding)
        }
 }
 
-int cpupower_set_turbo_boost(int turbo_boost)
+int cpupower_set_generic_turbo_boost(int turbo_boost)
 {
        char path[SYSFS_PATH_MAX];
        char linebuf[2] = {};