On Mon, Nov 09, 2015 at 05:29:23PM +0000, Punit Agrawal wrote:
> Register passive cooling devices when initialising cpufreq on
> big.LITTLE systems. If the device tree provides a dynamic power
> coefficient for the CPUs then the bound cooling device will support
> the extensions that allow it to be used with all the existing thermal
> governors including the power allocator governor.
> 
> A cooling device will be created per individual frequency domain and
> can be bound to thermal zones via the thermal DT bindings.
> 
> Signed-off-by: Punit Agrawal <punit.agra...@arm.com>
> Acked-by: Viresh Kumar <viresh.ku...@linaro.org>
> Cc: Sudeep Holla <sudeep.ho...@arm.com>
> Cc: Eduardo Valentin <edubez...@gmail.com>
> ---
>  drivers/cpufreq/arm_big_little.c | 52 
> ++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 50 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cpufreq/arm_big_little.c 
> b/drivers/cpufreq/arm_big_little.c
> index f1e42f8..72a2777 100644
> --- a/drivers/cpufreq/arm_big_little.c
> +++ b/drivers/cpufreq/arm_big_little.c
> @@ -23,6 +23,7 @@
>  #include <linux/cpu.h>
>  #include <linux/cpufreq.h>
>  #include <linux/cpumask.h>
> +#include <linux/cpu_cooling.h>
>  #include <linux/export.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
> @@ -55,6 +56,10 @@ static bool bL_switching_enabled;
>  #define ACTUAL_FREQ(cluster, freq)  ((cluster == A7_CLUSTER) ? freq << 1 : 
> freq)
>  #define VIRT_FREQ(cluster, freq)    ((cluster == A7_CLUSTER) ? freq >> 1 : 
> freq)
>  
> +struct private_data {
> +     struct thermal_cooling_device *cdev;
> +};
> +

My first impression was that this is redundant and you could store the
pointer to cdev in driver_data itself.  But seeing that it's mirroring
the structure in cpufreq-dt and it's simpler to do it this way I guess
it's ok to create this struct with only one pointer.  You can add my

Reviewed-by: Javi Merino <javi.mer...@arm.com>

>  static struct cpufreq_arm_bL_ops *arm_bL_ops;
>  static struct clk *clk[MAX_CLUSTERS];
>  static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS + 1];
> @@ -440,6 +445,7 @@ static int bL_cpufreq_init(struct cpufreq_policy *policy)
>  {
>       u32 cur_cluster = cpu_to_cluster(policy->cpu);
>       struct device *cpu_dev;
> +     struct private_data *priv;
>       int ret;
>  
>       cpu_dev = get_cpu_device(policy->cpu);
> @@ -457,9 +463,15 @@ static int bL_cpufreq_init(struct cpufreq_policy *policy)
>       if (ret) {
>               dev_err(cpu_dev, "CPU %d, cluster: %d invalid freq table\n",
>                               policy->cpu, cur_cluster);
> -             put_cluster_clk_and_freq_table(cpu_dev);
> -             return ret;
> +             goto out_free_cpufreq_table;
> +     }
> +
> +     priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> +     if (!priv) {
> +             ret = -ENOMEM;
> +             goto out_free_cpufreq_table;
>       }
> +     policy->driver_data = priv;
>  
>       if (cur_cluster < MAX_CLUSTERS) {
>               int cpu;
> @@ -484,12 +496,19 @@ static int bL_cpufreq_init(struct cpufreq_policy 
> *policy)
>  
>       dev_info(cpu_dev, "%s: CPU %d initialized\n", __func__, policy->cpu);
>       return 0;
> +
> +out_free_cpufreq_table:
> +     put_cluster_clk_and_freq_table(cpu_dev);
> +
> +     return ret;
>  }
>  
>  static int bL_cpufreq_exit(struct cpufreq_policy *policy)
>  {
>       struct device *cpu_dev;
> +     struct private_data *priv = policy->driver_data;
>  
> +     cpufreq_cooling_unregister(priv->cdev);
>       cpu_dev = get_cpu_device(policy->cpu);
>       if (!cpu_dev) {
>               pr_err("%s: failed to get cpu%d device\n", __func__,
> @@ -498,11 +517,39 @@ static int bL_cpufreq_exit(struct cpufreq_policy 
> *policy)
>       }
>  
>       put_cluster_clk_and_freq_table(cpu_dev);
> +     kfree(priv);
>       dev_dbg(cpu_dev, "%s: Exited, cpu: %d\n", __func__, policy->cpu);
>  
>       return 0;
>  }
>  
> +static void bL_cpufreq_ready(struct cpufreq_policy *policy)
> +{
> +     struct device *cpu_dev = get_cpu_device(policy->cpu);
> +     struct device_node *np = of_node_get(cpu_dev->of_node);
> +     struct private_data *priv = policy->driver_data;
> +
> +     if (WARN_ON(!np))
> +             return;
> +
> +     if (of_find_property(np, "#cooling-cells", NULL)) {
> +             u32 power_coefficient = 0;
> +
> +             of_property_read_u32(np, "dynamic-power-coefficient",
> +                                  &power_coefficient);
> +
> +             priv->cdev = of_cpufreq_power_cooling_register(np,
> +                             policy->related_cpus, power_coefficient, NULL);
> +             if (IS_ERR(priv->cdev)) {
> +                     dev_err(cpu_dev,
> +                             "running cpufreq without cooling device: %ld\n",
> +                             PTR_ERR(priv->cdev));
> +                     priv->cdev = NULL;
> +             }
> +     }
> +     of_node_put(np);
> +}
> +
>  static struct cpufreq_driver bL_cpufreq_driver = {
>       .name                   = "arm-big-little",
>       .flags                  = CPUFREQ_STICKY |
> @@ -513,6 +560,7 @@ static struct cpufreq_driver bL_cpufreq_driver = {
>       .get                    = bL_cpufreq_get_rate,
>       .init                   = bL_cpufreq_init,
>       .exit                   = bL_cpufreq_exit,
> +     .ready                  = bL_cpufreq_ready,
>       .attr                   = cpufreq_generic_attr,
>  };
>  
> -- 
> 2.5.3
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to