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

From: Marek Vasut
Date: Wed May 03 2017 - 10:51:50 EST


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