Calculate hwp_boost_threshold_busy_pct (task busy percent, which is
worth boosting) and hwp_boost_pstate_threshold (Don't boost if
CPU already has some performance) based on platform, min, max and
turbo frequencies.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com>
---
 drivers/cpufreq/intel_pstate.c | 40 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index ec455af..c43edce 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1463,6 +1463,42 @@ static inline int intel_pstate_get_sched_util(struct 
cpudata *cpu)
        return util * 100 / max;
 }
 
+
+static inline void intel_pstate_update_busy_threshold(struct cpudata *cpu)
+{
+       if (!hwp_boost_threshold_busy_pct) {
+               int min_freq, max_freq;
+
+               min_freq  = cpu->pstate.min_pstate * cpu->pstate.scaling;
+               update_turbo_state();
+               max_freq =  global.turbo_disabled || global.no_turbo ?
+                               cpu->pstate.max_freq : cpu->pstate.turbo_freq;
+
+               /*
+                * We are guranteed to get atleast min P-state. If we assume
+                * P-state is proportional to load (such that 10% load
+                * increase will result in 10% P-state increase), we will
+                * get at least min P-state till we have atleast
+                * (min * 100/max) percent cpu load. So any load less than
+                * than this this we shouldn't do any boost. Then boosting
+                * is not free, we will add atleast 20% offset.
+                */
+               hwp_boost_threshold_busy_pct = min_freq * 100 / max_freq;
+               hwp_boost_threshold_busy_pct += 20;
+               pr_debug("hwp_boost_threshold_busy_pct = %d\n",
+                        hwp_boost_threshold_busy_pct);
+       }
+
+       /* P1 percent out of total range of P-states */
+       if (cpu->pstate.max_freq != cpu->pstate.turbo_freq) {
+               hwp_boost_pstate_threshold =
+                       cpu->pstate.max_freq * SCHED_CAPACITY_SCALE / 
cpu->pstate.turbo_freq;
+               pr_debug("hwp_boost_pstate_threshold = %d\n",
+                        hwp_boost_pstate_threshold);
+       }
+
+}
+
 static inline void intel_pstate_update_util_hwp(struct update_util_data *data,
                                                u64 time, unsigned int flags)
 {
@@ -2061,8 +2097,10 @@ static int __intel_pstate_cpu_init(struct cpufreq_policy 
*policy)
 
        policy->fast_switch_possible = true;
 
-       if (hwp_active)
+       if (hwp_active) {
                csd_init(cpu);
+               intel_pstate_update_busy_threshold(cpu);
+       }
 
        return 0;
 }
-- 
2.9.5

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