tools/power turbostat: Print the C-state Pre-wake settings

C-state pre-wake setting[1] is an optimization for some Intel CPUs to
be woken up from deep C-states in order to reduce latency. According to
the spec, the BIT30 is the C-state Pre-wake Disable. Expose this setting
accordingly.
Sample output from turbostat:
...
cpu51: MSR_IA32_POWER_CTL: 0x1a00a40059 (C1E auto-promotion: DISabled)
C-state Pre-wake: ENabled
cpu51: MSR_TURBO_RATIO_LIMIT: 0x2021212121212224
...

[1] https://intel.github.io/wult/#c-state-pre-wake

Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 9ec13f06c0f33cc5d1299ba9a165dd3af291404a..e1ed14c666dbbb421fe982e55e2d90c2e868cf17 100644 (file)
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -91,6 +91,7 @@ double rapl_dram_energy_units, rapl_energy_units;
 double rapl_joule_counter_range;
 unsigned int do_core_perf_limit_reasons;
 unsigned int has_automatic_cstate_conversion;
+unsigned int dis_cstate_prewake;
 unsigned int do_gfx_perf_limit_reasons;
 unsigned int do_ring_perf_limit_reasons;
 unsigned int crystal_hz;
@@ -2271,6 +2272,8 @@ calculate_tsc_tweak()
        tsc_tweak = base_hz / tsc_hz;
 }
 
+void prewake_cstate_probe(unsigned int family, unsigned int model);
+
 static void
 dump_nhm_platform_info(void)
 {
@@ -2293,6 +2296,11 @@ dump_nhm_platform_info(void)
        fprintf(outf, "cpu%d: MSR_IA32_POWER_CTL: 0x%08llx (C1E auto-promotion: %sabled)\n",
                base_cpu, msr, msr & 0x2 ? "EN" : "DIS");
 
+       /* C-state Pre-wake Disable (CSTATE_PREWAKE_DISABLE) */
+       if (dis_cstate_prewake)
+               fprintf(outf, "C-state Pre-wake: %sabled\n",
+                       msr & 0x40000000 ? "DIS" : "EN");
+
        return;
 }
 
@@ -4546,6 +4554,12 @@ void automatic_cstate_conversion_probe(unsigned int family, unsigned int model)
                has_automatic_cstate_conversion = 1;
 }
 
+void prewake_cstate_probe(unsigned int family, unsigned int model)
+{
+       if (is_icx(family, model))
+               dis_cstate_prewake = 1;
+}
+
 int print_thermal(struct thread_data *t, struct core_data *c, struct pkg_data *p)
 {
        unsigned long long msr;