[linux-pm] [RFC PATCH 3/5] thermal: cpu_cooling: Add support to find nearby frequency levels.

amit daniel kachhap amit.daniel at samsung.com
Mon May 19 02:20:12 PDT 2014


On Fri, May 16, 2014 at 12:22 AM, Eduardo Valentin <edubezval at gmail.com> wrote:
> Hello Amit,
>
> On Thu, May 08, 2014 at 08:07:58PM +0530, Amit Daniel Kachhap wrote:
>> This patch adds suuport to get P state ceil/floor level for nearest frequency.
>> This will be used for consolidating ACPI cpufreq cooling via the generic cpu
>> cooling framework.
>>
>> Signed-off-by: Amit Daniel Kachhap <amit.daniel at samsung.com>
>> ---
>>  drivers/thermal/cpu_cooling.c                   |   42 +++++++++++++++++------
>>  drivers/thermal/samsung/exynos_thermal_common.c |    3 +-
>>  include/linux/cpu_cooling.h                     |   23 ++++++++++++-
>>  3 files changed, 55 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
>> index e2aeb36..6f5430e 100644
>> --- a/drivers/thermal/cpu_cooling.c
>> +++ b/drivers/thermal/cpu_cooling.c
>> @@ -120,12 +120,7 @@ static int is_cpufreq_valid(int cpu)
>>       return !cpufreq_get_policy(&policy, cpu);
>>  }
>>
>> -enum cpufreq_cooling_property {
>> -     GET_LEVEL,
>> -     GET_FREQ,
>> -     GET_MAXL,
>> -};
>> -
>> +#define GET_FREQ (GET_MAXL + 1)
>
> What happens if we add another level manipulating after GET_MAXL? say,
> GET_MINL?
yes correct. Good catch.
>
>>  /**
>>   * get_property - fetch a property of interest for a give cpu.
>>   * @cpu: cpu for which the property is required
>> @@ -207,15 +202,37 @@ static int get_property(unsigned int cpu, unsigned long input,
>>               /* now we have a valid frequency entry */
>>               freq = table[i].frequency;
>>
>> -             if (property == GET_LEVEL && (unsigned int)input == freq) {
>> +             if (property == GET_LEVEL_EXACT &&
>> +                                     (unsigned int)input == freq) {
>>                       /* get level by frequency */
>>                       *output = descend ? j : (max_level - j);
>>                       return 0;
>> -             }
>> -             if (property == GET_FREQ && level == j) {
>> +             } else if (property == GET_FREQ && level == j) {
>>                       /* get frequency by level */
>>                       *output = freq;
>>                       return 0;
>> +             } else if (property == GET_LEVEL_FLOOR) {
>> +                     /* get minimum possible level by frequency */
>> +                     if (descend && freq <= input) {
>> +                             *output = j;
>> +                             return 0;
>> +                     } else if (!descend) {
>> +                             if (freq <= input)
>> +                                     *output = (max_level - j);
>> +                             else
>> +                                     return 0;
>> +                     }
>> +             } else if (property == GET_LEVEL_CEIL) {
>> +                     /* get maximum possible level by frequency */
>> +                     if (!descend && freq >= input) {
>> +                             *output = (max_level - j);
>> +                             return 0;
>> +                     } else if (descend) {
>> +                             if (freq >= input)
>> +                                     *output = j;
>> +                             else
>> +                                     return 0;
>> +                     }
>>               }
>>               j++;
>>       }
>> @@ -227,6 +244,8 @@ static int get_property(unsigned int cpu, unsigned long input,
>>   * cpufreq_cooling_get_level - for a give cpu, return the cooling level.
>>   * @cpu: cpu for which the level is required
>>   * @freq: the frequency of interest
>> + * @property: can be GET_LEVEL_CEIL, GET_LEVEL_FLOOR, GET_LEVEL_EXACT or
>> + * GET_MAXL
>>   *
>>   * This function will match the cooling level corresponding to the
>>   * requested @freq and return it.
>> @@ -234,11 +253,12 @@ static int get_property(unsigned int cpu, unsigned long input,
>>   * Return: The matched cooling level on success or THERMAL_CSTATE_INVALID
>>   * otherwise.
>>   */
>> -unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq)
>> +unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq,
>> +                     enum cpufreq_cooling_property property)
>>  {
>>       unsigned int val;
>>
>> -     if (get_property(cpu, (unsigned long)freq, &val, GET_LEVEL))
>> +     if (get_property(cpu, (unsigned long)freq, &val, property))
>>               return THERMAL_CSTATE_INVALID;
>>
>>       return (unsigned long)val;
>> diff --git a/drivers/thermal/samsung/exynos_thermal_common.c b/drivers/thermal/samsung/exynos_thermal_common.c
>> index a7306fa..aa4696b 100644
>> --- a/drivers/thermal/samsung/exynos_thermal_common.c
>> +++ b/drivers/thermal/samsung/exynos_thermal_common.c
>> @@ -156,7 +156,8 @@ static int exynos_bind(struct thermal_zone_device *thermal,
>>       /* Bind the thermal zone to the cpufreq cooling device */
>>       for (i = 0; i < tab_size; i++) {
>>               clip_data = (struct freq_clip_table *)&(tab_ptr[i]);
>> -             level = cpufreq_cooling_get_level(0, clip_data->freq_clip_max);
>> +             level = cpufreq_cooling_get_level(0, clip_data->freq_clip_max,
>> +                                             GET_LEVEL_EXACT);
>>               if (level == THERMAL_CSTATE_INVALID)
>>                       return 0;
>>               switch (GET_ZONE(i)) {
>> diff --git a/include/linux/cpu_cooling.h b/include/linux/cpu_cooling.h
>> index f786935..f4d2b0e 100644
>> --- a/include/linux/cpu_cooling.h
>> +++ b/include/linux/cpu_cooling.h
>> @@ -44,6 +44,13 @@ struct cpufreq_cooling_status {
>>       void *devdata;
>>  };
>>
>> +enum cpufreq_cooling_property {
>> +     GET_LEVEL_CEIL,
>> +     GET_LEVEL_FLOOR,
>> +     GET_LEVEL_EXACT,
>> +     GET_MAXL,
>> +};
>
> Please document this enum.
>
>> +
>>  #ifdef CONFIG_CPU_THERMAL
>>  /**
>>   * cpufreq_cooling_register - function to create cpufreq cooling device.
>> @@ -77,7 +84,21 @@ of_cpufreq_cooling_register(struct device_node *np,
>>   */
>>  void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev);
>>
>> -unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq);
>> +/**
>> + * cpufreq_cooling_get_level - for a give cpu, return the cooling level.
>> + * @cpu: cpu for which the level is required
>> + * @freq: the frequency of interest
>> + * @property: can be GET_LEVEL_CEIL, GET_LEVEL_FLOOR, GET_LEVEL_EXACT or
>> + * GET_MAXL
>> + *
>> + * This function will match the cooling level corresponding to the
>> + * requested @freq and return it.
>> + *
>> + * Return: The matched cooling level on success or THERMAL_CSTATE_INVALID
>> + * otherwise.
>> + */
>> +unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq,
>> +                                     enum cpufreq_cooling_property);
>>
>>  /**
>>   * cpufreq_cooling_register_notifier - register a driver with cpufreq cooling.
>> --
>> 1.7.1
>>
>> --
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