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path: root/drivers/cpufreq/powernv-cpufreq.c
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Diffstat (limited to 'drivers/cpufreq/powernv-cpufreq.c')
-rw-r--r--drivers/cpufreq/powernv-cpufreq.c222
1 files changed, 155 insertions, 67 deletions
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 547890fd9..39ac78c94 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -28,6 +28,8 @@
#include <linux/of.h>
#include <linux/reboot.h>
#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <trace/events/power.h>
#include <asm/cputhreads.h>
#include <asm/firmware.h>
@@ -43,15 +45,39 @@
static struct cpufreq_frequency_table powernv_freqs[POWERNV_MAX_PSTATES+1];
static bool rebooting, throttled, occ_reset;
+static const char * const throttle_reason[] = {
+ "No throttling",
+ "Power Cap",
+ "Processor Over Temperature",
+ "Power Supply Failure",
+ "Over Current",
+ "OCC Reset"
+};
+
+enum throttle_reason_type {
+ NO_THROTTLE = 0,
+ POWERCAP,
+ CPU_OVERTEMP,
+ POWER_SUPPLY_FAILURE,
+ OVERCURRENT,
+ OCC_RESET_THROTTLE,
+ OCC_MAX_REASON
+};
+
static struct chip {
unsigned int id;
bool throttled;
+ bool restore;
+ u8 throttle_reason;
cpumask_t mask;
struct work_struct throttle;
- bool restore;
+ int throttle_turbo;
+ int throttle_sub_turbo;
+ int reason[OCC_MAX_REASON];
} *chips;
static int nr_chips;
+static DEFINE_PER_CPU(struct chip *, chip_info);
/*
* Note: The set of pstates consists of contiguous integers, the
@@ -183,6 +209,42 @@ static struct freq_attr *powernv_cpu_freq_attr[] = {
NULL,
};
+#define throttle_attr(name, member) \
+static ssize_t name##_show(struct cpufreq_policy *policy, char *buf) \
+{ \
+ struct chip *chip = per_cpu(chip_info, policy->cpu); \
+ \
+ return sprintf(buf, "%u\n", chip->member); \
+} \
+ \
+static struct freq_attr throttle_attr_##name = __ATTR_RO(name) \
+
+throttle_attr(unthrottle, reason[NO_THROTTLE]);
+throttle_attr(powercap, reason[POWERCAP]);
+throttle_attr(overtemp, reason[CPU_OVERTEMP]);
+throttle_attr(supply_fault, reason[POWER_SUPPLY_FAILURE]);
+throttle_attr(overcurrent, reason[OVERCURRENT]);
+throttle_attr(occ_reset, reason[OCC_RESET_THROTTLE]);
+throttle_attr(turbo_stat, throttle_turbo);
+throttle_attr(sub_turbo_stat, throttle_sub_turbo);
+
+static struct attribute *throttle_attrs[] = {
+ &throttle_attr_unthrottle.attr,
+ &throttle_attr_powercap.attr,
+ &throttle_attr_overtemp.attr,
+ &throttle_attr_supply_fault.attr,
+ &throttle_attr_overcurrent.attr,
+ &throttle_attr_occ_reset.attr,
+ &throttle_attr_turbo_stat.attr,
+ &throttle_attr_sub_turbo_stat.attr,
+ NULL,
+};
+
+static const struct attribute_group throttle_attr_grp = {
+ .name = "throttle_stats",
+ .attrs = throttle_attrs,
+};
+
/* Helper routines */
/* Access helpers to power mgt SPR */
@@ -311,34 +373,36 @@ static inline unsigned int get_nominal_index(void)
static void powernv_cpufreq_throttle_check(void *data)
{
+ struct chip *chip;
unsigned int cpu = smp_processor_id();
unsigned long pmsr;
- int pmsr_pmax, i;
+ int pmsr_pmax;
pmsr = get_pmspr(SPRN_PMSR);
-
- for (i = 0; i < nr_chips; i++)
- if (chips[i].id == cpu_to_chip_id(cpu))
- break;
+ chip = this_cpu_read(chip_info);
/* Check for Pmax Capping */
pmsr_pmax = (s8)PMSR_MAX(pmsr);
if (pmsr_pmax != powernv_pstate_info.max) {
- if (chips[i].throttled)
+ if (chip->throttled)
goto next;
- chips[i].throttled = true;
- if (pmsr_pmax < powernv_pstate_info.nominal)
- pr_crit("CPU %d on Chip %u has Pmax reduced below nominal frequency (%d < %d)\n",
- cpu, chips[i].id, pmsr_pmax,
- powernv_pstate_info.nominal);
- else
- pr_info("CPU %d on Chip %u has Pmax reduced below turbo frequency (%d < %d)\n",
- cpu, chips[i].id, pmsr_pmax,
- powernv_pstate_info.max);
- } else if (chips[i].throttled) {
- chips[i].throttled = false;
- pr_info("CPU %d on Chip %u has Pmax restored to %d\n", cpu,
- chips[i].id, pmsr_pmax);
+ chip->throttled = true;
+ if (pmsr_pmax < powernv_pstate_info.nominal) {
+ pr_warn_once("CPU %d on Chip %u has Pmax reduced below nominal frequency (%d < %d)\n",
+ cpu, chip->id, pmsr_pmax,
+ powernv_pstate_info.nominal);
+ chip->throttle_sub_turbo++;
+ } else {
+ chip->throttle_turbo++;
+ }
+ trace_powernv_throttle(chip->id,
+ throttle_reason[chip->throttle_reason],
+ pmsr_pmax);
+ } else if (chip->throttled) {
+ chip->throttled = false;
+ trace_powernv_throttle(chip->id,
+ throttle_reason[chip->throttle_reason],
+ pmsr_pmax);
}
/* Check if Psafe_mode_active is set in PMSR. */
@@ -356,7 +420,7 @@ next:
if (throttled) {
pr_info("PMSR = %16lx\n", pmsr);
- pr_crit("CPU Frequency could be throttled\n");
+ pr_warn("CPU Frequency could be throttled\n");
}
}
@@ -397,6 +461,21 @@ static int powernv_cpufreq_cpu_init(struct cpufreq_policy *policy)
for (i = 0; i < threads_per_core; i++)
cpumask_set_cpu(base + i, policy->cpus);
+ if (!policy->driver_data) {
+ int ret;
+
+ ret = sysfs_create_group(&policy->kobj, &throttle_attr_grp);
+ if (ret) {
+ pr_info("Failed to create throttle stats directory for cpu %d\n",
+ policy->cpu);
+ return ret;
+ }
+ /*
+ * policy->driver_data is used as a flag for one-time
+ * creation of throttle sysfs files.
+ */
+ policy->driver_data = policy;
+ }
return cpufreq_table_validate_and_show(policy, powernv_freqs);
}
@@ -423,18 +502,19 @@ 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;
+ cpumask_t mask;
- smp_call_function_any(&chip->mask,
+ get_online_cpus();
+ cpumask_and(&mask, &chip->mask, cpu_online_mask);
+ smp_call_function_any(&mask,
powernv_cpufreq_throttle_check, NULL, 0);
if (!chip->restore)
- return;
+ goto out;
chip->restore = false;
- cpumask_copy(mask, &chip->mask);
- for_each_cpu_and(cpu, mask, cpu_online_mask) {
- int index, tcpu;
+ for_each_cpu(cpu, &mask) {
+ int index;
struct cpufreq_policy policy;
cpufreq_get_policy(&policy, cpu);
@@ -442,20 +522,12 @@ void powernv_cpufreq_work_fn(struct work_struct *work)
policy.cur,
CPUFREQ_RELATION_C, &index);
powernv_cpufreq_target_index(&policy, index);
- for_each_cpu(tcpu, policy.cpus)
- cpumask_clear_cpu(tcpu, mask);
+ cpumask_andnot(&mask, &mask, policy.cpus);
}
+out:
+ put_online_cpus();
}
-static char throttle_reason[][30] = {
- "No throttling",
- "Power Cap",
- "Processor Over Temperature",
- "Power Supply Failure",
- "Over Current",
- "OCC Reset"
- };
-
static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
unsigned long msg_type, void *_msg)
{
@@ -481,7 +553,7 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
*/
if (!throttled) {
throttled = true;
- pr_crit("CPU frequency is throttled for duration\n");
+ pr_warn("CPU frequency is throttled for duration\n");
}
break;
@@ -505,23 +577,20 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
return 0;
}
- if (omsg.throttle_status &&
- omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS)
- pr_info("OCC: Chip %u Pmax reduced due to %s\n",
- (unsigned int)omsg.chip,
- throttle_reason[omsg.throttle_status]);
- else if (!omsg.throttle_status)
- pr_info("OCC: Chip %u %s\n", (unsigned int)omsg.chip,
- throttle_reason[omsg.throttle_status]);
- else
- return 0;
-
for (i = 0; i < nr_chips; i++)
- if (chips[i].id == omsg.chip) {
- if (!omsg.throttle_status)
- chips[i].restore = true;
- schedule_work(&chips[i].throttle);
- }
+ if (chips[i].id == omsg.chip)
+ break;
+
+ if (omsg.throttle_status >= 0 &&
+ omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS) {
+ chips[i].throttle_reason = omsg.throttle_status;
+ chips[i].reason[omsg.throttle_status]++;
+ }
+
+ if (!omsg.throttle_status)
+ chips[i].restore = true;
+
+ schedule_work(&chips[i].throttle);
}
return 0;
}
@@ -566,21 +635,33 @@ static int init_chip_info(void)
}
}
- chips = kmalloc_array(nr_chips, sizeof(struct chip), GFP_KERNEL);
+ chips = kcalloc(nr_chips, sizeof(struct chip), GFP_KERNEL);
if (!chips)
return -ENOMEM;
for (i = 0; i < nr_chips; i++) {
chips[i].id = chip[i];
- 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;
+ for_each_cpu(cpu, &chips[i].mask)
+ per_cpu(chip_info, cpu) = &chips[i];
}
return 0;
}
+static inline void clean_chip_info(void)
+{
+ kfree(chips);
+}
+
+static inline void unregister_all_notifiers(void)
+{
+ opal_message_notifier_unregister(OPAL_MSG_OCC,
+ &powernv_cpufreq_opal_nb);
+ unregister_reboot_notifier(&powernv_cpufreq_reboot_nb);
+}
+
static int __init powernv_cpufreq_init(void)
{
int rc = 0;
@@ -591,28 +672,35 @@ static int __init powernv_cpufreq_init(void)
/* Discover pstates from device tree and init */
rc = init_powernv_pstates();
- if (rc) {
- pr_info("powernv-cpufreq disabled. System does not support PState control\n");
- return rc;
- }
+ if (rc)
+ goto out;
/* Populate chip info */
rc = init_chip_info();
if (rc)
- return rc;
+ goto out;
register_reboot_notifier(&powernv_cpufreq_reboot_nb);
opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb);
- return cpufreq_register_driver(&powernv_cpufreq_driver);
+
+ rc = cpufreq_register_driver(&powernv_cpufreq_driver);
+ if (!rc)
+ return 0;
+
+ pr_info("Failed to register the cpufreq driver (%d)\n", rc);
+ unregister_all_notifiers();
+ clean_chip_info();
+out:
+ pr_info("Platform driver disabled. System does not support PState control\n");
+ return rc;
}
module_init(powernv_cpufreq_init);
static void __exit powernv_cpufreq_exit(void)
{
- unregister_reboot_notifier(&powernv_cpufreq_reboot_nb);
- opal_message_notifier_unregister(OPAL_MSG_OCC,
- &powernv_cpufreq_opal_nb);
cpufreq_unregister_driver(&powernv_cpufreq_driver);
+ unregister_all_notifiers();
+ clean_chip_info();
}
module_exit(powernv_cpufreq_exit);