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path: root/drivers/cpufreq/cpufreq.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r--drivers/cpufreq/cpufreq.c98
1 files changed, 77 insertions, 21 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 3938c7817095..67bc2ece7b4b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -41,7 +41,7 @@ static struct cpufreq_driver *cpufreq_driver;
static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
#ifdef CONFIG_HOTPLUG_CPU
/* This one keeps track of the previously set governor of a removed CPU */
-static DEFINE_PER_CPU(struct cpufreq_governor *, cpufreq_cpu_governor);
+static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor);
#endif
static DEFINE_SPINLOCK(cpufreq_driver_lock);
@@ -64,14 +64,14 @@ static DEFINE_SPINLOCK(cpufreq_driver_lock);
* - Lock should not be held across
* __cpufreq_governor(data, CPUFREQ_GOV_STOP);
*/
-static DEFINE_PER_CPU(int, policy_cpu);
+static DEFINE_PER_CPU(int, cpufreq_policy_cpu);
static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem);
#define lock_policy_rwsem(mode, cpu) \
int lock_policy_rwsem_##mode \
(int cpu) \
{ \
- int policy_cpu = per_cpu(policy_cpu, cpu); \
+ int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \
BUG_ON(policy_cpu == -1); \
down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \
if (unlikely(!cpu_online(cpu))) { \
@@ -90,7 +90,7 @@ EXPORT_SYMBOL_GPL(lock_policy_rwsem_write);
void unlock_policy_rwsem_read(int cpu)
{
- int policy_cpu = per_cpu(policy_cpu, cpu);
+ int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu);
BUG_ON(policy_cpu == -1);
up_read(&per_cpu(cpu_policy_rwsem, policy_cpu));
}
@@ -98,7 +98,7 @@ EXPORT_SYMBOL_GPL(unlock_policy_rwsem_read);
void unlock_policy_rwsem_write(int cpu)
{
- int policy_cpu = per_cpu(policy_cpu, cpu);
+ int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu);
BUG_ON(policy_cpu == -1);
up_write(&per_cpu(cpu_policy_rwsem, policy_cpu));
}
@@ -647,6 +647,21 @@ static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
return policy->governor->show_setspeed(policy, buf);
}
+/**
+ * show_scaling_driver - show the current cpufreq HW/BIOS limitation
+ */
+static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf)
+{
+ unsigned int limit;
+ int ret;
+ if (cpufreq_driver->bios_limit) {
+ ret = cpufreq_driver->bios_limit(policy->cpu, &limit);
+ if (!ret)
+ return sprintf(buf, "%u\n", limit);
+ }
+ return sprintf(buf, "%u\n", policy->cpuinfo.max_freq);
+}
+
#define define_one_ro(_name) \
static struct freq_attr _name = \
__ATTR(_name, 0444, show_##_name, NULL)
@@ -666,6 +681,7 @@ define_one_ro(cpuinfo_transition_latency);
define_one_ro(scaling_available_governors);
define_one_ro(scaling_driver);
define_one_ro(scaling_cur_freq);
+define_one_ro(bios_limit);
define_one_ro(related_cpus);
define_one_ro(affected_cpus);
define_one_rw(scaling_min_freq);
@@ -767,17 +783,20 @@ static struct kobj_type ktype_cpufreq = {
* 0: Success
* Positive: When we have a managed CPU and the sysfs got symlinked
*/
-int cpufreq_add_dev_policy(unsigned int cpu, struct cpufreq_policy *policy,
- struct sys_device *sys_dev)
+static int cpufreq_add_dev_policy(unsigned int cpu,
+ struct cpufreq_policy *policy,
+ struct sys_device *sys_dev)
{
int ret = 0;
#ifdef CONFIG_SMP
unsigned long flags;
unsigned int j;
-
#ifdef CONFIG_HOTPLUG_CPU
- if (per_cpu(cpufreq_cpu_governor, cpu)) {
- policy->governor = per_cpu(cpufreq_cpu_governor, cpu);
+ struct cpufreq_governor *gov;
+
+ gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu));
+ if (gov) {
+ policy->governor = gov;
dprintk("Restoring governor %s for cpu %d\n",
policy->governor->name, cpu);
}
@@ -799,7 +818,7 @@ int cpufreq_add_dev_policy(unsigned int cpu, struct cpufreq_policy *policy,
/* Set proper policy_cpu */
unlock_policy_rwsem_write(cpu);
- per_cpu(policy_cpu, cpu) = managed_policy->cpu;
+ per_cpu(cpufreq_policy_cpu, cpu) = managed_policy->cpu;
if (lock_policy_rwsem_write(cpu) < 0) {
/* Should not go through policy unlock path */
@@ -840,7 +859,8 @@ int cpufreq_add_dev_policy(unsigned int cpu, struct cpufreq_policy *policy,
/* symlink affected CPUs */
-int cpufreq_add_dev_symlink(unsigned int cpu, struct cpufreq_policy *policy)
+static int cpufreq_add_dev_symlink(unsigned int cpu,
+ struct cpufreq_policy *policy)
{
unsigned int j;
int ret = 0;
@@ -867,8 +887,9 @@ int cpufreq_add_dev_symlink(unsigned int cpu, struct cpufreq_policy *policy)
return ret;
}
-int cpufreq_add_dev_interface(unsigned int cpu, struct cpufreq_policy *policy,
- struct sys_device *sys_dev)
+static int cpufreq_add_dev_interface(unsigned int cpu,
+ struct cpufreq_policy *policy,
+ struct sys_device *sys_dev)
{
struct cpufreq_policy new_policy;
struct freq_attr **drv_attr;
@@ -900,13 +921,18 @@ int cpufreq_add_dev_interface(unsigned int cpu, struct cpufreq_policy *policy,
if (ret)
goto err_out_kobj_put;
}
+ if (cpufreq_driver->bios_limit) {
+ ret = sysfs_create_file(&policy->kobj, &bios_limit.attr);
+ if (ret)
+ goto err_out_kobj_put;
+ }
spin_lock_irqsave(&cpufreq_driver_lock, flags);
for_each_cpu(j, policy->cpus) {
if (!cpu_online(j))
continue;
per_cpu(cpufreq_cpu_data, j) = policy;
- per_cpu(policy_cpu, j) = policy->cpu;
+ per_cpu(cpufreq_policy_cpu, j) = policy->cpu;
}
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
@@ -949,10 +975,13 @@ err_out_kobj_put:
static int cpufreq_add_dev(struct sys_device *sys_dev)
{
unsigned int cpu = sys_dev->id;
- int ret = 0;
+ int ret = 0, found = 0;
struct cpufreq_policy *policy;
unsigned long flags;
unsigned int j;
+#ifdef CONFIG_HOTPLUG_CPU
+ int sibling;
+#endif
if (cpu_is_offline(cpu))
return 0;
@@ -991,7 +1020,7 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
cpumask_copy(policy->cpus, cpumask_of(cpu));
/* Initially set CPU itself as the policy_cpu */
- per_cpu(policy_cpu, cpu) = cpu;
+ per_cpu(cpufreq_policy_cpu, cpu) = cpu;
ret = (lock_policy_rwsem_write(cpu) < 0);
WARN_ON(ret);
@@ -999,7 +1028,19 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
INIT_WORK(&policy->update, handle_update);
/* Set governor before ->init, so that driver could check it */
- policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+#ifdef CONFIG_HOTPLUG_CPU
+ for_each_online_cpu(sibling) {
+ struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling);
+ if (cp && cp->governor &&
+ (cpumask_test_cpu(cpu, cp->related_cpus))) {
+ policy->governor = cp->governor;
+ found = 1;
+ break;
+ }
+ }
+#endif
+ if (!found)
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
/* call driver. From then on the cpufreq must be able
* to accept all calls to ->verify and ->setpolicy for this CPU
*/
@@ -1111,7 +1152,8 @@ static int __cpufreq_remove_dev(struct sys_device *sys_dev)
#ifdef CONFIG_SMP
#ifdef CONFIG_HOTPLUG_CPU
- per_cpu(cpufreq_cpu_governor, cpu) = data->governor;
+ strncpy(per_cpu(cpufreq_cpu_governor, cpu), data->governor->name,
+ CPUFREQ_NAME_LEN);
#endif
/* if we have other CPUs still registered, we need to unlink them,
@@ -1135,7 +1177,8 @@ static int __cpufreq_remove_dev(struct sys_device *sys_dev)
continue;
dprintk("removing link for cpu %u\n", j);
#ifdef CONFIG_HOTPLUG_CPU
- per_cpu(cpufreq_cpu_governor, j) = data->governor;
+ strncpy(per_cpu(cpufreq_cpu_governor, j),
+ data->governor->name, CPUFREQ_NAME_LEN);
#endif
cpu_sys_dev = get_cpu_sysdev(j);
sysfs_remove_link(&cpu_sys_dev->kobj, "cpufreq");
@@ -1606,9 +1649,22 @@ EXPORT_SYMBOL_GPL(cpufreq_register_governor);
void cpufreq_unregister_governor(struct cpufreq_governor *governor)
{
+#ifdef CONFIG_HOTPLUG_CPU
+ int cpu;
+#endif
+
if (!governor)
return;
+#ifdef CONFIG_HOTPLUG_CPU
+ for_each_present_cpu(cpu) {
+ if (cpu_online(cpu))
+ continue;
+ if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name))
+ strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0");
+ }
+#endif
+
mutex_lock(&cpufreq_governor_mutex);
list_del(&governor->governor_list);
mutex_unlock(&cpufreq_governor_mutex);
@@ -1946,7 +2002,7 @@ static int __init cpufreq_core_init(void)
int cpu;
for_each_possible_cpu(cpu) {
- per_cpu(policy_cpu, cpu) = -1;
+ per_cpu(cpufreq_policy_cpu, cpu) = -1;
init_rwsem(&per_cpu(cpu_policy_rwsem, cpu));
}