Message-ID: <c1fad818-1858-2e81-84fd-03cfb54d8938@linaro.org>
Date:   Tue, 24 Jan 2023 18:55:18 +0100
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Subject: Re: [PATCH v7 4/4] thermal: mediatek: add another get_temp ops for
 thermal sensors
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To:     Amjad Ouled-Ameur <aouledameur@baylibre.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Amit Kucheria <amitk@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Zhang Rui <rui.zhang@intel.com>
Cc:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Fabien Parent <fparent@baylibre.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Markus Schneider-Pargmann <msp@baylibre.com>,
        linux-pm@vger.kernel.org, Rob Herring <robh@kernel.org>,
        Michael Kao <michael.kao@mediatek.com>,
        linux-kernel@vger.kernel.org, Hsin-Yi Wang <hsinyi@chromium.org>,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, devicetree@vger.kernel.org
References: <20221018-up-i350-thermal-bringup-v7-0-ebf08ff2eddb@baylibre.com>
 <20221018-up-i350-thermal-bringup-v7-4-ebf08ff2eddb@baylibre.com>
 <4121bb6b-30db-7a23-f4c8-40afdda7a0b5@linaro.org>
 <COTTJX635TNF.1WL2TEZN7VW9O@amjad-ThinkPad-T490>
 <adfe41f7-00e5-876b-7803-3127919fba13@linaro.org>
 <COUMF3IZ9Y63.LA3KFHJSUZIC@amjad-ThinkPad-T490>
 <0644aede-c281-3919-50e0-4466f6587d81@linaro.org>
 <187b0fe1-1f14-d8b8-c827-1e824da0b1d3@baylibre.com>
 <d3daece0-ed23-fae7-9bc8-c6e53b84e8e7@baylibre.com>
 <9f9547a2-69dd-f91d-c587-289156bf9d55@linaro.org>
 <2950b824-ad2f-2579-a956-a03d157453eb@baylibre.com>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
In-Reply-To: <2950b824-ad2f-2579-a956-a03d157453eb@baylibre.com>
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Precedence: bulk

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 ?


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