linux-kernel - Re: [PATCH] ARM: dts: imx6sx-sdb: Remove cpufreq OPP override

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: <1af9275a-45ad-67a7-9f59-0677a33cf3a7@denx.de>
Date:   Wed, 3 May 2017 16:51:35 +0200
From:   Marek Vasut <marex@...x.de>
To:     Shawn Guo <shawnguo@...nel.org>
Cc:     Leonard Crestez <leonard.crestez@....com>,
        Fabio Estevam <festevam@...il.com>,
        Sascha Hauer <kernel@...gutronix.de>,
        Peter Chen <Peter.Chen@....com>,
        Anson Huang <Anson.Huang@....com>,
        "linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        Fabio Estevam <fabio.estevam@....com>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        Christoph Fritz <chf.fritz@...glemail.com>
Subject: Re: [PATCH] ARM: dts: imx6sx-sdb: Remove cpufreq OPP override

On 05/03/2017 04:41 PM, Shawn Guo wrote:
> On Wed, May 03, 2017 at 04:32:06PM +0200, Marek Vasut wrote:
>> On 05/03/2017 04:26 PM, Marek Vasut wrote:
>>> On 05/03/2017 03:57 PM, Shawn Guo wrote:
>>>> On Tue, Apr 25, 2017 at 07:28:06PM +0200, Marek Vasut wrote:
>>>>> On 04/25/2017 07:23 PM, Leonard Crestez wrote:
>>>>>> Anyway, that version also sets the supply for reg_arm and reg_soc. It
>>>>>> is not necessary for fixing the crash I'm seeing but is good because it
>>>>>> will result in the minimum voltage on VDD_ARM_SOC_IN rather than a fix
>>>>>> 1375mv. I tested Marek's patch and it works fine on my rev B board
>>>>>> (which otherwise fails to boot upstream).
>>>>>
>>>>> Oh that's nice , thanks ! I don't have SDB and I hacked it up after a
>>>>> brief discussion with Fabio without even compile-testing it, thus RFC.
>>>>> Glad to hear it works and thanks for testing it ! Can you add a formal
>>>>> Tested-by please ?
>>>>
>>>> Hi Marek,
>>>
>>> Hi Shawn,
>>>
>>>> Thanks for your patch.  But I prefer Leonard's version because: 1) it
>>>> has a better commit log; 2) it sticks to one-patch-does-one-thing
>>>> policy.
>>>
>>> Well I'd prefer this patch because
>>> 1) It has T-B
>>
>> Correction, two TBs [1]
>>
>> [1] https://patchwork.kernel.org/patch/9698749/
> 
> That doesn't mean Leonard's patch hasn't been tested by anyone.

That's what the T-B tags are for ...

>>> 2) It actually fixes a problem with the voltage rails such that the DVFS
>>>    works without leaving the system in unstable or dead state. You do
>>>    need the second part of my patch if you drop the OPP hackery, without
>>>    it the power framework cannot correctly configure the core voltages,
>>>    so the patch from Leonard makes things worse.
> 
> If that's true, I will change my mind.

Well you can check the schematic ... the ARM and SOC rails share the
same upstream regulator.

-- 
Best regards,
Marek Vasut