[PATCH v7 4/4] thermal: mediatek: add another get_temp ops for thermal sensors

Daniel Lezcano daniel.lezcano at linaro.org
Tue Jan 24 09:55:18 PST 2023


On 24/01/2023 18:46, Amjad Ouled-Ameur wrote:
> 
> On 1/24/23 17:54, Daniel Lezcano wrote:
>>
>> Hi Amjad,
>>
>> On 24/01/2023 11:08, Amjad Ouled-Ameur wrote:
>>
>> [ ... ]
>>
>>>>>
>>>>> IIUC, there is a sensor per couple of cores. 1 x 2Bigs, 1 x 2Bigs, 
>>>>> 1 x 4 Little, right ?
>>>>
>>>> MT8365 SoC has 4 x A53 CPUs. The SoC has 4 thermal zones per sensor. 
>>>> Thermal zone 0 corresponds
>>>>
>>>> to all 4 x A53 CPUs, the other thermal zones (1, 2 and 3) has 
>>>> nothing to do with CPUs. The cooling device type
>>>>
>>>> used for CPUs is passive. FYI, thermal zones 1, 2 and 3 are present 
>>>> in the SoC for debug-purpose only, they are not supposed
>>>>
>>>> to be used for production.
>>>>
>>> After reconsidering the fact that zones 1, 2 and 3 are only used for 
>>> dev/debug, it might be best to avo >
>>> aggregation as you suggested, and keep only support for zone 0 in 
>>> this driver. Thus I suggest I send a V8
>>>
>>> where I keep only below fixes for this patch if that's okay with you:
>>>
>>> - Define "raw_to_mcelsius" function pointer for "struct 
>>> thermal_bank_cfg".
>>>
>>> - Fix "mtk_thermal" variable in mtk_read_temp().
>>>
>>> - Set "mt->raw_to_mcelsius" in probe().
>>>
>>>
>>> For zones 1, 2 and 3 we can later add a different driver specific for 
>>> dev/debug to probe them to
>>>
>>> avoid confusion.
>>
>> You can add them in the driver and in the device tree, but just add 
>> the cooling device for the thermal zone 0.
> 
> Thermal zone 0 uses CPU{0..3} for passive cooling, in this case we 
> should register cooling device with
> 
> cpufreq_cooling_register() for each CPU right ?

No, the OF code device tree does already that. You just have to register 
the different thermal zones.

Do you have a pointer to a device tree for this board and the thermal 
setup ?


-- 
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog




More information about the linux-arm-kernel mailing list