lkml.org 
[lkml]   [2019]   [Sep]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [Letux-kernel] [RFC PATCH 0/3] Enable 1GHz support on omap36xx
From
Date

> Am 09.09.2019 um 18:38 schrieb Adam Ford <aford173@gmail.com>:
>
> On Mon, Sep 9, 2019 at 11:32 AM Tony Lindgren <tony@atomide.com> wrote:
>>
>> Hi,
>>
>> * H. Nikolaus Schaller <hns@goldelico.com> [190909 14:57]:
>>> Another question that came up by private mail from André was if we
>>> should better disable the turbo OPPs of omap34xx and 36xx by default
>>> (status = "disabled";) because there are concerns about overheating
>>> the chips and we have no thermal regulation like for omap4 & 5.
>
> I thought there was a thermal sensor?

Yes.

>
> cpu_thermal: cpu_thermal {
> polling-delay-passive = <250>; /* milliseconds */
> polling-delay = <1000>; /* milliseconds */
> coefficients = <0 20000>;
>
> /* sensor ID */
> thermal-sensors = <&bandgap 0>;
> };
>
> Can this driver somehow notify the cpufreq that we've hit some limit?
> I know it's not as accurate as one would like, but even for non-1GHz
> versions, having it downclock would be a good thing when running at
> extreme temps.

Indeed it is not really reliable. For me it jumps up by 10° between first
reading within the next second (and seems to stay at this offset after first use).

But yes, I think it should be possible to use it similar to omap5-core-thermal.dtsi

Maybe we have to add "trips" and "core_crit". This must obviously be linked to
the cpufreq system. Or is it done automatically?

BR,
Nikolaus

\
 
 \ /
  Last update: 2019-09-09 19:03    [W:0.162 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site