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>

1 files changed, 29 insertions, 2 deletions

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 90b42938837e..546e056e416d 100644
--- 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;