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-rw-r--r--drivers/cpufreq/Kconfig27
-rw-r--r--drivers/cpufreq/cpufreq.c12
-rw-r--r--drivers/cpufreq/cpufreq_conservative.c19
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c22
4 files changed, 53 insertions, 27 deletions
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 993fa7b8925..721f86f4f00 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -56,10 +56,6 @@ config CPU_FREQ_STAT_DETAILS
If in doubt, say N.
-# Note that it is not currently possible to set the other governors (such as ondemand)
-# as the default, since if they fail to initialise, cpufreq will be
-# left in an undefined state.
-
choice
prompt "Default CPUFreq governor"
default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110
@@ -85,6 +81,29 @@ config CPU_FREQ_DEFAULT_GOV_USERSPACE
program shall be able to set the CPU dynamically without having
to enable the userspace governor manually.
+config CPU_FREQ_DEFAULT_GOV_ONDEMAND
+ bool "ondemand"
+ select CPU_FREQ_GOV_ONDEMAND
+ select CPU_FREQ_GOV_PERFORMANCE
+ help
+ Use the CPUFreq governor 'ondemand' as default. This allows
+ you to get a full dynamic frequency capable system by simply
+ loading your cpufreq low-level hardware driver.
+ Be aware that not all cpufreq drivers support the ondemand
+ governor. If unsure have a look at the help section of the
+ driver. Fallback governor will be the performance governor.
+
+config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
+ bool "conservative"
+ select CPU_FREQ_GOV_CONSERVATIVE
+ select CPU_FREQ_GOV_PERFORMANCE
+ help
+ Use the CPUFreq governor 'conservative' as default. This allows
+ you to get a full dynamic frequency capable system by simply
+ loading your cpufreq low-level hardware driver.
+ Be aware that not all cpufreq drivers support the conservative
+ governor. If unsure have a look at the help section of the
+ driver. Fallback governor will be the performance governor.
endchoice
config CPU_FREQ_GOV_PERFORMANCE
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 9528bd57736..418522f88f7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1484,6 +1484,18 @@ static int __cpufreq_governor(struct cpufreq_policy *policy,
unsigned int event)
{
int ret;
+ struct cpufreq_governor *gov = CPUFREQ_PERFORMANCE_GOVERNOR;
+
+ if (policy->governor->max_transition_latency &&
+ policy->cpuinfo.transition_latency >
+ policy->governor->max_transition_latency) {
+ printk(KERN_WARNING "%s governor failed, too long"
+ " transition latency of HW, fallback"
+ " to %s governor\n",
+ policy->governor->name,
+ gov->name);
+ policy->governor = gov;
+ }
if (!try_module_get(policy->governor->owner))
return -EINVAL;
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 26f440ccc3f..4bd33ce8a6f 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -58,7 +58,7 @@ static unsigned int def_sampling_rate;
#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000)
#define DEF_SAMPLING_DOWN_FACTOR (1)
#define MAX_SAMPLING_DOWN_FACTOR (10)
-#define TRANSITION_LATENCY_LIMIT (10 * 1000)
+#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
static void do_dbs_timer(struct work_struct *work);
@@ -466,9 +466,6 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
(!policy->cur))
return -EINVAL;
- if (policy->cpuinfo.transition_latency >
- (TRANSITION_LATENCY_LIMIT * 1000))
- return -EINVAL;
if (this_dbs_info->enable) /* Already enabled */
break;
@@ -551,15 +548,17 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
return 0;
}
-static struct cpufreq_governor cpufreq_gov_dbs = {
- .name = "conservative",
- .governor = cpufreq_governor_dbs,
- .owner = THIS_MODULE,
+struct cpufreq_governor cpufreq_gov_conservative = {
+ .name = "conservative",
+ .governor = cpufreq_governor_dbs,
+ .max_transition_latency = TRANSITION_LATENCY_LIMIT,
+ .owner = THIS_MODULE,
};
+EXPORT_SYMBOL(cpufreq_gov_conservative);
static int __init cpufreq_gov_dbs_init(void)
{
- return cpufreq_register_governor(&cpufreq_gov_dbs);
+ return cpufreq_register_governor(&cpufreq_gov_conservative);
}
static void __exit cpufreq_gov_dbs_exit(void)
@@ -567,7 +566,7 @@ static void __exit cpufreq_gov_dbs_exit(void)
/* Make sure that the scheduled work is indeed not running */
flush_scheduled_work();
- cpufreq_unregister_governor(&cpufreq_gov_dbs);
+ cpufreq_unregister_governor(&cpufreq_gov_conservative);
}
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index e794527e492..369f4459515 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -47,7 +47,7 @@ static unsigned int def_sampling_rate;
(def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
#define MAX_SAMPLING_RATE (500 * def_sampling_rate)
#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000)
-#define TRANSITION_LATENCY_LIMIT (10 * 1000)
+#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
static void do_dbs_timer(struct work_struct *work);
@@ -508,12 +508,6 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
if ((!cpu_online(cpu)) || (!policy->cur))
return -EINVAL;
- if (policy->cpuinfo.transition_latency >
- (TRANSITION_LATENCY_LIMIT * 1000)) {
- printk(KERN_WARNING "ondemand governor failed to load "
- "due to too long transition latency\n");
- return -EINVAL;
- }
if (this_dbs_info->enable) /* Already enabled */
break;
@@ -585,11 +579,13 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
return 0;
}
-static struct cpufreq_governor cpufreq_gov_dbs = {
- .name = "ondemand",
- .governor = cpufreq_governor_dbs,
- .owner = THIS_MODULE,
+struct cpufreq_governor cpufreq_gov_ondemand = {
+ .name = "ondemand",
+ .governor = cpufreq_governor_dbs,
+ .max_transition_latency = TRANSITION_LATENCY_LIMIT,
+ .owner = THIS_MODULE,
};
+EXPORT_SYMBOL(cpufreq_gov_ondemand);
static int __init cpufreq_gov_dbs_init(void)
{
@@ -598,12 +594,12 @@ static int __init cpufreq_gov_dbs_init(void)
printk(KERN_ERR "Creation of kondemand failed\n");
return -EFAULT;
}
- return cpufreq_register_governor(&cpufreq_gov_dbs);
+ return cpufreq_register_governor(&cpufreq_gov_ondemand);
}
static void __exit cpufreq_gov_dbs_exit(void)
{
- cpufreq_unregister_governor(&cpufreq_gov_dbs);
+ cpufreq_unregister_governor(&cpufreq_gov_ondemand);
destroy_workqueue(kondemand_wq);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-29 10:06:28 +0000