cpufreq / intel_pstate: Change to scale off of max P-state
Change to using max P-state instead of max turbo P-state. This
change resolves two issues.
On a quiet system intel_pstate can fail to respond to a load change.
On CPU SKUs that have a limited number of P-states and no turbo range
intel_pstate fails to select the highest available P-state.
This change is suitable for stable v3.9+
References: https://bugzilla.kernel.org/show_bug.cgi?id=59481
Reported-and-tested-by: Arjan van de Ven <arjan@linux.intel.com>
Reported-and-tested-by: dsmythies@telus.net
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index b012d76..7cde885 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -103,10 +103,10 @@
static struct pstate_adjust_policy default_policy = {
.sample_rate_ms = 10,
.deadband = 0,
- .setpoint = 109,
- .p_gain_pct = 17,
+ .setpoint = 97,
+ .p_gain_pct = 20,
.d_gain_pct = 0,
- .i_gain_pct = 4,
+ .i_gain_pct = 0,
};
struct perf_limits {
@@ -468,12 +468,12 @@
static inline int intel_pstate_get_scaled_busy(struct cpudata *cpu)
{
int32_t busy_scaled;
- int32_t core_busy, turbo_pstate, current_pstate;
+ int32_t core_busy, max_pstate, current_pstate;
core_busy = int_tofp(cpu->samples[cpu->sample_ptr].core_pct_busy);
- turbo_pstate = int_tofp(cpu->pstate.turbo_pstate);
+ max_pstate = int_tofp(cpu->pstate.max_pstate);
current_pstate = int_tofp(cpu->pstate.current_pstate);
- busy_scaled = mul_fp(core_busy, div_fp(turbo_pstate, current_pstate));
+ busy_scaled = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
return fp_toint(busy_scaled);
}
