On Fri, Feb 7, 2014 at 9:46 PM, Nishanth Menon <nm at ti.com> wrote:
> On 02/07/2014 09:55 AM, Thomas Abraham wrote:
>> From: Thomas Abraham <thomas.ab at samsung.com>
>>
>> Lookup for the optional boost-frequency property in cpu0 node and if
>> available, enable support for boost mode frequencies. The frequencies
>> usable in boost mode are determined while preparing the cpufreq table
>> from the list of operating points available.
>>
>> In addition to this, enable the CPU_FREQ_BOOST_SW config option for
>> this driver by default. On platforms that do not support boost mode,
>> the boost mode frequencies will not be specified in cpu0 node and
>> hence the boost mode support will not be enabled. Since this driver
>> anyways depends on THERMAL config option, it is safe to enable
>> CPU_FREQ_BOOST_SW config option as default.
>>
>> Cc: Shawn Guo <shawn.guo at linaro.org>
>> Cc: Lukasz Majewski <l.majewski at samsung.com>
>> Signed-off-by: Thomas Abraham <thomas.ab at samsung.com>
>> ---
>> Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt | 2 ++
>> drivers/cpufreq/Kconfig | 1 +
>> drivers/cpufreq/cpufreq-cpu0.c | 3 +++
>> 3 files changed, 6 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
>> index f055515..60f321a 100644
>> --- a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
>> +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
>> @@ -19,6 +19,8 @@ Optional properties:
>> - cooling-min-level:
>> - cooling-max-level:
>> Please refer to Documentation/devicetree/bindings/thermal/thermal.txt.
>> +- boost-frequency:
>> + Please refer to Documentation/devicetree/bindings/cpufreq/cpufreq-boost.txt
>>
>> Examples:
>>
>> diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
>> index 4b029c0..52cc704 100644
>> --- a/drivers/cpufreq/Kconfig
>> +++ b/drivers/cpufreq/Kconfig
>> @@ -187,6 +187,7 @@ config GENERIC_CPUFREQ_CPU0
>> tristate "Generic CPU0 cpufreq driver"
>> depends on HAVE_CLK && REGULATOR && OF && THERMAL && CPU_THERMAL
>> select PM_OPP
>> + select CPU_FREQ_BOOST_SW
>> help
>> This adds a generic cpufreq driver for CPU0 frequency management.
>> It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
>> diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
>> index 0c12ffc..06539eb 100644
>> --- a/drivers/cpufreq/cpufreq-cpu0.c
>> +++ b/drivers/cpufreq/cpufreq-cpu0.c
>> @@ -195,6 +195,9 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev)
>> transition_latency += ret * 1000;
>> }
>>
>> + if (of_find_property(cpu_dev->of_node, "boost-frequency", NULL))
>> + cpu0_cpufreq_driver.boost_supported = true;
>> +
>> ret = cpufreq_register_driver(&cpu0_cpufreq_driver);
>> if (ret) {
>> pr_err("failed register driver: %d\n", ret);
>>
>
> might as well hide that under the opp api which returns a bool that
> says if boost is supported or not. that allows the parse to be
> isolated to a single location.
This is specific to the cpufreq-cpu0 driver. Other cpufreq drivers
might want to use other methods and additional constraints to
determine if boost has to be enabled.
Thanks,
Thomas.
>
> --
> Regards,
> Nishanth Menon