linux-kernel - Re: [PATCH] ARM: dts: exynos: Use thermal fuse value for thermal zone 0 on Exynos5420

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CANAwSgQ94irFT6kkeRao6rqnXO0ejTAozSegu2Y3DLsLWJe9=w@mail.gmail.com>
Date:   Mon, 13 Feb 2017 17:51:06 +0530
From:   Anand Moon <linux.amoon@...il.com>
To:     Krzysztof Kozlowski <krzk@...nel.org>
Cc:     Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
        Zhang Rui <rui.zhang@...el.com>,
        Eduardo Valentin <edubezval@...il.com>,
        Kukjin Kim <kgene@...nel.org>,
        Javier Martinez Canillas <javier@....samsung.com>,
        Linux PM list <linux-pm@...r.kernel.org>,
        "linux-samsung-soc@...r.kernel.org" 
        <linux-samsung-soc@...r.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
        Linux Kernel <linux-kernel@...r.kernel.org>,
        devicetree <devicetree@...r.kernel.org>,
        Willy WOLFF <willy.mh.wolff@...il.com>
Subject: Re: [PATCH] ARM: dts: exynos: Use thermal fuse value for thermal zone
 0 on Exynos5420

Hi Krzysztof,

On 13 February 2017 at 17:29, Krzysztof Kozlowski <krzk@...nel.org> wrote:
> On Mon, Feb 13, 2017 at 1:38 PM, Anand Moon <linux.amoon@...il.com> wrote:
>> Hi Krzysztof,
>>
>>
>>
>> On 12 February 2017 at 01:44, Krzysztof Kozlowski <krzk@...nel.org> wrote:
>>> In Odroid XU3 Lite board, the temperature levels reported for thermal
>>> zone 0 were weird. In warm room:
>>>         /sys/class/thermal/thermal_zone0/temp:32000
>>>         /sys/class/thermal/thermal_zone1/temp:51000
>>>         /sys/class/thermal/thermal_zone2/temp:55000
>>>         /sys/class/thermal/thermal_zone3/temp:54000
>>>         /sys/class/thermal/thermal_zone4/temp:51000
>>>
>>> Sometimes after booting the value was even equal to ambient temperature
>>> which is highly unlikely to be a real temperature of sensor in SoC.
>>>
>>> The thermal sensor's calibration (trimming) is based on fused values.
>>> In case of the board above, the fused values are: 35, 52, 43, 58 and 43
>>> (corresponding to each TMU device).  However driver defined a minimum value
>>> for fused data as 40 and for smaller values it was using a hard-coded 55
>>> instead.  This lead to mapping data from sensor to wrong temperatures
>>> for thermal zone 0.
>>>
>>> Various vendor 3.10 trees (Hardkernel's based on Samsung LSI, Artik 10)
>>> do not impose any limits on fused values.  Since we do not have any
>>> knowledge about these limits, use 0 as a minimum accepted fused value.
>>> This should essentially allow accepting any reasonable fused value thus
>>> behaving like vendor driver.
>>>
>>
>> On HK following values are define in drivers/thermal/exynos_thermal.c
>>
>> #define EFUSE_MIN_VALUE                         40
>> #define EFUSE_MAX_VALUE                         100
>
> Are they being used?

Opps: sorry it's not used for Exynos5422 platform.

Best regards,
-Anand