diff options
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/acpi-cpufreq.c | 4 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq-cpu0.c | 7 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 34 | ||||
| -rw-r--r-- | drivers/cpufreq/exynos5440-cpufreq.c | 2 | ||||
| -rw-r--r-- | drivers/cpufreq/imx6q-cpufreq.c | 7 |
5 files changed, 40 insertions, 14 deletions
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index a1260b4549db..d2c3253e015e 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -986,6 +986,10 @@ static int __init acpi_cpufreq_init(void) { int ret; + /* don't keep reloading if cpufreq_driver exists */ + if (cpufreq_get_current_driver()) + return 0; + if (acpi_disabled) return 0; diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c index cbfffa91ebdd..78c49d8e0f4a 100644 --- a/drivers/cpufreq/cpufreq-cpu0.c +++ b/drivers/cpufreq/cpufreq-cpu0.c @@ -12,6 +12,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/clk.h> +#include <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/err.h> #include <linux/module.h> @@ -177,7 +178,11 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev) struct device_node *np; int ret; - cpu_dev = &pdev->dev; + cpu_dev = get_cpu_device(0); + if (!cpu_dev) { + pr_err("failed to get cpu0 device\n"); + return -ENODEV; + } np = of_node_get(cpu_dev->of_node); if (!np) { diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 43c24aa756f6..04548f7023af 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -952,9 +952,20 @@ static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) if (cpu == policy->cpu) return; + /* + * Take direct locks as lock_policy_rwsem_write wouldn't work here. + * Also lock for last cpu is enough here as contention will happen only + * after policy->cpu is changed and after it is changed, other threads + * will try to acquire lock for new cpu. And policy is already updated + * by then. + */ + down_write(&per_cpu(cpu_policy_rwsem, policy->cpu)); + policy->last_cpu = policy->cpu; policy->cpu = cpu; + up_write(&per_cpu(cpu_policy_rwsem, policy->last_cpu)); + #ifdef CONFIG_CPU_FREQ_TABLE cpufreq_frequency_table_update_policy_cpu(policy); #endif @@ -1125,7 +1136,7 @@ static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, int ret; /* first sibling now owns the new sysfs dir */ - cpu_dev = get_cpu_device(cpumask_first(policy->cpus)); + cpu_dev = get_cpu_device(cpumask_any_but(policy->cpus, old_cpu)); /* Don't touch sysfs files during light-weight tear-down */ if (frozen) @@ -1189,12 +1200,9 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, policy->governor->name, CPUFREQ_NAME_LEN); #endif - WARN_ON(lock_policy_rwsem_write(cpu)); + lock_policy_rwsem_read(cpu); cpus = cpumask_weight(policy->cpus); - - if (cpus > 1) - cpumask_clear_cpu(cpu, policy->cpus); - unlock_policy_rwsem_write(cpu); + unlock_policy_rwsem_read(cpu); if (cpu != policy->cpu) { if (!frozen) @@ -1203,9 +1211,7 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu, frozen); if (new_cpu >= 0) { - WARN_ON(lock_policy_rwsem_write(cpu)); update_policy_cpu(policy, new_cpu); - unlock_policy_rwsem_write(cpu); if (!frozen) { pr_debug("%s: policy Kobject moved to cpu: %d " @@ -1237,9 +1243,12 @@ static int __cpufreq_remove_dev_finish(struct device *dev, return -EINVAL; } - lock_policy_rwsem_read(cpu); + WARN_ON(lock_policy_rwsem_write(cpu)); cpus = cpumask_weight(policy->cpus); - unlock_policy_rwsem_read(cpu); + + if (cpus > 1) + cpumask_clear_cpu(cpu, policy->cpus); + unlock_policy_rwsem_write(cpu); /* If cpu is last user of policy, free policy */ if (cpus == 1) { @@ -1451,6 +1460,9 @@ unsigned int cpufreq_get(unsigned int cpu) { unsigned int ret_freq = 0; + if (cpufreq_disabled() || !cpufreq_driver) + return -ENOENT; + if (!down_read_trylock(&cpufreq_rwsem)) return 0; @@ -2095,7 +2107,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) write_lock_irqsave(&cpufreq_driver_lock, flags); if (cpufreq_driver) { write_unlock_irqrestore(&cpufreq_driver_lock, flags); - return -EBUSY; + return -EEXIST; } cpufreq_driver = driver_data; write_unlock_irqrestore(&cpufreq_driver_lock, flags); diff --git a/drivers/cpufreq/exynos5440-cpufreq.c b/drivers/cpufreq/exynos5440-cpufreq.c index d514c152fd1a..be5380ecdcd4 100644 --- a/drivers/cpufreq/exynos5440-cpufreq.c +++ b/drivers/cpufreq/exynos5440-cpufreq.c @@ -457,7 +457,7 @@ err_free_table: opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table); err_put_node: of_node_put(np); - dev_err(dvfs_info->dev, "%s: failed initialization\n", __func__); + dev_err(&pdev->dev, "%s: failed initialization\n", __func__); return ret; } diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c index 3e396543aea4..c3fd2a101ca0 100644 --- a/drivers/cpufreq/imx6q-cpufreq.c +++ b/drivers/cpufreq/imx6q-cpufreq.c @@ -7,6 +7,7 @@ */ #include <linux/clk.h> +#include <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/delay.h> #include <linux/err.h> @@ -202,7 +203,11 @@ static int imx6q_cpufreq_probe(struct platform_device *pdev) unsigned long min_volt, max_volt; int num, ret; - cpu_dev = &pdev->dev; + cpu_dev = get_cpu_device(0); + if (!cpu_dev) { + pr_err("failed to get cpu0 device\n"); + return -ENODEV; + } np = of_node_get(cpu_dev->of_node); if (!np) { |