cpufreq: intel_pstate: Take CPUFREQ_GOV_STRICT_TARGET into account

Make intel_pstate take the new CPUFREQ_GOV_STRICT_TARGET governor
flag into account when it operates in the passive mode with HWP
enabled, so as to fix the "powersave" governor behavior in that
case (currently, HWP is allowed to scale the performance all the
way up to the policy max limit when the "powersave" governor is
used, but it should be constrained to the policy min limit then).

Fixes: e43b6ae4dc34 ("cpufreq: intel_pstate: Implement passive mode with HWP enabled")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+: 5826b0a49c4c cpufreq: Introduce governor flags
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+: 45137389a87d cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGET
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+: 323b8f498f16 cpufreq: Add strict_target to struct cpufreq_policy

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index b7a9779250aaa5f5e4160effe0bd7a33caba6569..36a3ccfe6d3d1cce010b0e08f74d82a72f6f36f0 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2527,7 +2527,7 @@ static void intel_cpufreq_trace(struct cpudata *cpu, unsigned int trace_type, in
 }
 
 static void intel_cpufreq_adjust_hwp(struct cpudata *cpu, u32 target_pstate,
-                                    bool fast_switch)
+                                    bool strict, bool fast_switch)
 {
        u64 prev = READ_ONCE(cpu->hwp_req_cached), value = prev;
 
@@ -2539,7 +2539,7 @@ static void intel_cpufreq_adjust_hwp(struct cpudata *cpu, u32 target_pstate,
         * field in it, so opportunistically update the max too if needed.
         */
        value &= ~HWP_MAX_PERF(~0L);
-       value |= HWP_MAX_PERF(cpu->max_perf_ratio);
+       value |= HWP_MAX_PERF(strict ? target_pstate : cpu->max_perf_ratio);
 
        if (value == prev)
                return;
@@ -2562,14 +2562,16 @@ static void intel_cpufreq_adjust_perf_ctl(struct cpudata *cpu,
                              pstate_funcs.get_val(cpu, target_pstate));
 }
 
-static int intel_cpufreq_update_pstate(struct cpudata *cpu, int target_pstate,
-                                      bool fast_switch)
+static int intel_cpufreq_update_pstate(struct cpufreq_policy *policy,
+                                      int target_pstate, bool fast_switch)
 {
+       struct cpudata *cpu = all_cpu_data[policy->cpu];
        int old_pstate = cpu->pstate.current_pstate;
 
        target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
        if (hwp_active) {
-               intel_cpufreq_adjust_hwp(cpu, target_pstate, fast_switch);
+               intel_cpufreq_adjust_hwp(cpu, target_pstate,
+                                        policy->strict_target, fast_switch);
                cpu->pstate.current_pstate = target_pstate;
        } else if (target_pstate != old_pstate) {
                intel_cpufreq_adjust_perf_ctl(cpu, target_pstate, fast_switch);
@@ -2609,7 +2611,7 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy,
                break;
        }
 
-       target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, false);
+       target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, false);
 
        freqs.new = target_pstate * cpu->pstate.scaling;
 
@@ -2628,7 +2630,7 @@ static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy,
 
        target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling);
 
-       target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, true);
+       target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, true);
 
        return target_pstate * cpu->pstate.scaling;
 }