This implements a simple variably low-pass-filtering governor in
control of the HWP MIN/MAX PERF range based on the previously
introduced get_vlp_target_range(). See "cpufreq: intel_pstate:
Implement VLP controller statistics and target range calculation." for
the rationale.
v3: Fix accidental overwrite of boot EPP setting in
intel_pstate_reset_vlp() (Srinivas). Rename
CPU_RESPONSE_FREQUENCY to CPU_SCALING_RESPONSE (Rafael). Define
generic CPUFREQ policy to control VLP governor (Rafael).
Signed-off-by: Francisco Jerez <currojerez@xxxxxxxxxx>
---
drivers/cpufreq/intel_pstate.c | 92 ++++++++++++++++++++++++++++++++--
1 file changed, 87 insertions(+), 5 deletions(-)
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index d13eb95a6271..0a315f681c43 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1913,6 +1913,20 @@ static void intel_pstate_reset_vlp(struct cpudata *cpu)
vlp->gain = max(1, div_fp(1000, vlp_params.setpoint_0_pml));
vlp->target.p_base = 0;
vlp->stats.last_scaling_response_hz = vlp_params.avg_hz;
+
+ if (hwp_active) {
+ const uint32_t p0 = max(cpu->pstate.min_pstate,
+ cpu->min_perf_ratio);
+ const uint32_t p1 = max_t(uint32_t, p0, cpu->max_perf_ratio);
+ const uint64_t hwp_req = (READ_ONCE(cpu->hwp_req_cached) &
+ ~(HWP_MAX_PERF(~0L) |
+ HWP_MIN_PERF(~0L) |
+ HWP_DESIRED_PERF(~0L))) |
+ HWP_MIN_PERF(p0) | HWP_MAX_PERF(p1);
+
+ wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, hwp_req);
+ WRITE_ONCE(cpu->hwp_req_cached, hwp_req);
+ }
}
/**
@@ -2230,6 +2244,46 @@ static void intel_pstate_adjust_pstate(struct cpudata *cpu)
fp_toint(cpu->iowait_boost * 100));
}
+static void intel_pstate_adjust_pstate_range(struct cpudata *cpu,
+ const unsigned int range[])
+{
+ const uint64_t hwp_req_cached = READ_ONCE(cpu->hwp_req_cached);
+ unsigned int p0, p1, p_min, p_max;
+ struct sample *sample;
+ uint64_t hwp_req;
+
+ update_turbo_state();
+
+ p0 = max(cpu->pstate.min_pstate, cpu->min_perf_ratio);
+ p1 = max_t(unsigned int, p0, cpu->max_perf_ratio);
+ p_min = clamp_t(unsigned int, range[0], p0, p1);
+ p_max = clamp_t(unsigned int, range[1], p0, p1);
+
+ trace_cpu_frequency(p_max * cpu->pstate.scaling, cpu->cpu);
+
+ hwp_req = (hwp_req_cached &
+ ~(HWP_MAX_PERF(~0L) | HWP_MIN_PERF(~0L) |
+ HWP_DESIRED_PERF(~0L))) |
+ HWP_MIN_PERF(vlp_params.debug & 2 ? p0 : p_min) |
+ HWP_MAX_PERF(vlp_params.debug & 4 ? p1 : p_max);
+
+ if (hwp_req != hwp_req_cached) {
+ wrmsrl(MSR_HWP_REQUEST, hwp_req);
+ WRITE_ONCE(cpu->hwp_req_cached, hwp_req);
+ }
+
+ sample = &cpu->sample;
+ trace_pstate_sample(mul_ext_fp(100, sample->core_avg_perf),
+ fp_toint(sample->busy_scaled),
+ hwp_req_cached,
+ hwp_req,
+ sample->mperf,
+ sample->aperf,
+ sample->tsc,
+ get_avg_frequency(cpu),
+ fp_toint(cpu->iowait_boost * 100));
+}
+
static void intel_pstate_update_util(struct update_util_data *data, u64 time,
unsigned int flags)
{
@@ -2268,6 +2322,22 @@ static void intel_pstate_update_util(struct update_util_data *data, u64 time,
intel_pstate_adjust_pstate(cpu);
}
+/**
+ * Implementation of the cpufreq update_util hook based on the VLP
+ * controller (see get_vlp_target_range()).
+ */
+static void intel_pstate_update_util_hwp_vlp(struct update_util_data *data,
+ u64 time, unsigned int flags)
+{
+ struct cpudata *cpu = container_of(data, struct cpudata, update_util);
+
+ if (update_vlp_sample(cpu, time, flags)) {
+ const struct vlp_target_range *target =
+ get_vlp_target_range(cpu);
+ intel_pstate_adjust_pstate_range(cpu, target->value);
+ }
+}
+
static struct pstate_funcs core_funcs = {
.get_max = core_get_max_pstate,
.get_max_physical = core_get_max_pstate_physical,
@@ -2418,15 +2488,25 @@ static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
intel_pstate_clear_update_util_hook(cpu_num);
if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE ||
- (hwp_active && !hwp_boost))
+ (cpu->policy != CPUFREQ_POLICY_ADAPTIVE &&
+ hwp_active && !hwp_boost))
return;
/* Prevent intel_pstate_update_util() from using stale data. */
cpu->sample.time = 0;
- cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
- (hwp_active ?
- intel_pstate_update_util_hwp :
- intel_pstate_update_util));
+
+ if (cpu->policy == CPUFREQ_POLICY_ADAPTIVE) {
+ cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
+ (hwp_active ?
+ intel_pstate_update_util_hwp_vlp :
+ intel_pstate_update_util));
+ } else {
+ cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
+ (hwp_active ?
+ intel_pstate_update_util_hwp :
+ intel_pstate_update_util));
+ }
+
cpu->update_util_set = true;
}
@@ -2529,6 +2609,8 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
if (hwp_active)
intel_pstate_hwp_set(policy->cpu);
+ intel_pstate_reset_vlp(cpu);
+
mutex_unlock(&intel_pstate_limits_lock);
return 0;
--
2.22.1
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