cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling

If frequency is throttled due to OCC reset then cpus will be in Psafe
frequency, so restore the frequency on all cpus to policy->cur when
OCCs are active again. And if frequency is throttled due to Pmax
capping then restore the frequency of all the cpus  in the chip on
unthrottling.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 90b4293..546e056 100644 (file)
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -48,6 +48,7 @@ static struct chip {
        bool throttled;
        cpumask_t mask;
        struct work_struct throttle;
+       bool restore;
 } *chips;
 
 static int nr_chips;
@@ -415,9 +416,29 @@ static struct notifier_block powernv_cpufreq_reboot_nb = {
 void powernv_cpufreq_work_fn(struct work_struct *work)
 {
        struct chip *chip = container_of(work, struct chip, throttle);
+       unsigned int cpu;
+       cpumask_var_t mask;
 
        smp_call_function_any(&chip->mask,
                              powernv_cpufreq_throttle_check, NULL, 0);
+
+       if (!chip->restore)
+               return;
+
+       chip->restore = false;
+       cpumask_copy(mask, &chip->mask);
+       for_each_cpu_and(cpu, mask, cpu_online_mask) {
+               int index, tcpu;
+               struct cpufreq_policy policy;
+
+               cpufreq_get_policy(&policy, cpu);
+               cpufreq_frequency_table_target(&policy, policy.freq_table,
+                                              policy.cur,
+                                              CPUFREQ_RELATION_C, &index);
+               powernv_cpufreq_target_index(&policy, index);
+               for_each_cpu(tcpu, policy.cpus)
+                       cpumask_clear_cpu(tcpu, mask);
+       }
 }
 
 static char throttle_reason[][30] = {
@@ -469,8 +490,10 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
                        throttled = false;
                        pr_info("OCC: Active\n");
 
-                       for (i = 0; i < nr_chips; i++)
+                       for (i = 0; i < nr_chips; i++) {
+                               chips[i].restore = true;
                                schedule_work(&chips[i].throttle);
+                       }
 
                        return 0;
                }
@@ -487,8 +510,11 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
                        return 0;
 
                for (i = 0; i < nr_chips; i++)
-                       if (chips[i].id == omsg.chip)
+                       if (chips[i].id == omsg.chip) {
+                               if (!omsg.throttle_status)
+                                       chips[i].restore = true;
                                schedule_work(&chips[i].throttle);
+                       }
        }
        return 0;
 }
@@ -542,6 +568,7 @@ static int init_chip_info(void)
                chips[i].throttled = false;
                cpumask_copy(&chips[i].mask, cpumask_of_node(chip[i]));
                INIT_WORK(&chips[i].throttle, powernv_cpufreq_work_fn);
+               chips[i].restore = false;
        }
 
        return 0;