Re: [PATCH] ARM: dts: Add CPU cooling binding for Exynos3250-based Rinato/Monk board

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

On 02.07.2015 15:11, Chanwoo Choi wrote:
> On 07/02/2015 02:54 PM, Krzysztof Kozlowski wrote:
>> On 02.07.2015 14:37, Chanwoo Choi wrote:
>>> This patch add the cooling device to control the overheating issue on
>>> Exynos3250-based Rinato/Monk board.
>>>
>>> Cc: Kukjin Kim <kgene@kernel.org>
>>> Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
>>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>>> ---
>>> Depends on:
>>> This patch needs the cpufreq support of Exynos3250 SoC. So, this patch has the
>>> dependency on patch[1] which support the generic cpufreq for Exynos3250 SoC.
>>> [1] https://lkml.org/lkml/2015/7/1/696
>>>     : [PATCH v6 0/3] cpufreq: Use cpufreq-dt driver for Exynos3250
>>>
>>>  arch/arm/boot/dts/exynos3250-monk.dts   | 15 +++++++++++++++
>>>  arch/arm/boot/dts/exynos3250-rinato.dts | 15 +++++++++++++++
>>>  arch/arm/boot/dts/exynos3250.dtsi       |  1 +
>>>  3 files changed, 31 insertions(+)
>>>
>>> diff --git a/arch/arm/boot/dts/exynos3250-monk.dts b/arch/arm/boot/dts/exynos3250-monk.dts
>>> index 7863265d4868..540a0adf2be6 100644
>>> --- a/arch/arm/boot/dts/exynos3250-monk.dts
>>> +++ b/arch/arm/boot/dts/exynos3250-monk.dts
>>> @@ -116,6 +116,21 @@
>>>  		min-microvolt = <1100000>;
>>>  		max-microvolt = <2700000>;
>>>  	};
>>> +
>>> +	thermal-zones {
>>> +		cpu_thermal: cpu-thermal {
>>> +			cooling-maps {
>>> +				map0 {
>>> +					/* Correspond to 500MHz at freq_table */
>>> +					cooling-device = <&cpu0 5 5>;
>>> +				};
>>> +				map1 {
>>> +					/* Correspond to 200MHz at freq_table */
>>> +					cooling-device = <&cpu0 8 8>;
>>> +				};
>>> +			};
>>> +		};
>>> +	};
>>>  };
>>>  
>>>  &adc {
>>> diff --git a/arch/arm/boot/dts/exynos3250-rinato.dts b/arch/arm/boot/dts/exynos3250-rinato.dts
>>> index ddd7ac283045..0e62a6435e07 100644
>>> --- a/arch/arm/boot/dts/exynos3250-rinato.dts
>>> +++ b/arch/arm/boot/dts/exynos3250-rinato.dts
>>> @@ -107,6 +107,21 @@
>>>  		min-microvolt = <1100000>;
>>>  		max-microvolt = <2700000>;
>>>  	};
>>> +
>>> +	thermal-zones {
>>> +		cpu_thermal: cpu-thermal {
>>> +			cooling-maps {
>>> +				map0 {
>>> +					/* Corresponds to 500MHz */
>>> +					cooling-device = <&cpu0 5 5>;
>>> +				};
>>> +				map1 {
>>> +					/* Corresponds to 200MHz */
>>> +					cooling-device = <&cpu0 8 8>;
>>> +				};
>>> +			};
>>> +		};
>>> +	};
>>>  };
>>>  
>>>  &adc {
>>> diff --git a/arch/arm/boot/dts/exynos3250.dtsi b/arch/arm/boot/dts/exynos3250.dtsi
>>> index e0f3b2ed41a3..a4931b660ddb 100644
>>> --- a/arch/arm/boot/dts/exynos3250.dtsi
>>> +++ b/arch/arm/boot/dts/exynos3250.dtsi
>>> @@ -55,6 +55,7 @@
>>>  			clock-frequency = <1000000000>;
>>>  			clocks = <&cmu CLK_ARM_CLK>;
>>>  			clock-names = "cpu";
>>> +			#cooling-cells = <2>;
>>>  
>>
>> Don't you need also cooling-{min,max}-state properties?
> 
> Yes, it is well working without cooling-{min,max}-state or cooling-{min,max}-level.
> 
> I look for the some code to parse "cooling-{min,max}-state or cooling-{min,max}-level"
> in drivers/thermal/*. But, there are no any code to parse it.
> 
> But, Documentation/devicetree/bindings/thermal/thermal.txt contains just the 'cooling-{min,max}-state.
> 
> I think that there are mismatch between document and thermal core driver.

Thanks for explanation, looks good.
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof