Re: [PATCH v4 02/20] PM / devfreq: exynos: Add documentation for generic exynos bus frequency driver

[Chanwoo Choi <cw00.choi@samsung.com>]

On 2015년 12월 14일 17:40, MyungJoo Ham wrote:
>>   
>>  This patch adds the documentation for generic exynos bus frequency
>> driver.
>>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> 
> A little changes following:
> 
>> ---
>>  .../devicetree/bindings/devfreq/exynos-bus.txt     | 93 ++++++++++++++++++++++
>>  1 file changed, 93 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>>
>> diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>> new file mode 100644
>> index 000000000000..e32daef328da
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>> @@ -0,0 +1,93 @@
>> +* Generic Exynos Bus frequency device
>> +
>> +The Samsung Exynos SoC have many buses for data transfer between DRAM
> 
> +The Samsung Exynos SoC has many buses for data transfer between DRAM
> 
> or
> 
> +The Samsung Exynos SoCs have many buses for data transfer between DRAM
> (because you intend to support mulitple Exynos SoCs)
> 
>> +and sub-blocks in SoC. Almost Exynos SoC have the common architecture
> 
> +and sub-blocks in SoC. Most Exynos SoCs share the common architecture
> 
>> +for buses. Generally, the each bus of Exynos SoC includes the source clock
> 
> +for buses. Generally, each bus of Exynos SoC includes a source clock
> 
>> +and power line and then is able to change the clock according to the usage
> 
> +and a power line, which are able to change the clock frequency 
> 
>> +of each buses on runtime. When gathering the usage of each buses on runtime,
> 
> +of the bus in runtime. To monitor the usage of each bus in runtime,
> 
>> +the driver uses the PPMU (Platform Performance Monitoring Unit) which
> 
> +the driver uses the PPMU (Platform Performance Monitoring Unit), which
> 
>> +is able to measure the current load of sub-blocks.
>> +
>> +There are a little different composition among Exynos SoC because each Exynos
>> +SoC has the different sub-blocks. So, this difference should be specified
> 
> +SoC has different sub-blocks. Therefore, such difference should be specified
> 
>> +in devicetree file instead of each device driver. In result, this driver
>> +is able to support the bus frequency for all Exynos SoCs.
>> +

Okay. I'll modify it.

Regards,
Chanwoo Choi