[PATCH v3 6/6] cpufreq: powernv: Restore cpu frequency to policy->cur on unthrottling

Shilpasri G Bhat
2015-05-04T09:02:02Z

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>
---
drivers/cpufreq/powernv-cpufreq.c | 31 +++++++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 0a59d5b..b2915bc 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -51,6 +51,7 @@ static struct chip {
bool throttled;
cpumask_t mask;
struct work_struct throttle;
+ bool restore;
} *chips;

static int nr_chips;
@@ -418,9 +419,29 @@ 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] = {
@@ -473,8 +494,10 @@ 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;
}
@@ -490,8 +513,11 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
return 0;

for (i = 0; i < nr_chips; i++)
- if (chips[i].id == chip_id)
+ if (chips[i].id == chip_id) {
+ if (!reason)
+ chips[i].restore = true;
schedule_work(&chips[i].throttle);
+ }
}
return 0;
}
@@ -545,6 +571,7 @@ 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;
--
1.9.3