Pinebook Pro instability problem and fix.

[Søren Schmidt]

> On 21 Feb 2020, at 00.45, Russell L. Carter <rcarter at pinyon.org> wrote:
> 
> Hi Søren,
> 
> On 2020-02-20 13:10, Søren Schmidt wrote:
>> Hi gang!
>> I have been wrestling my Pinebook Pro instability problem for some time.
>> The problem was that if I just let it boot it would occasionally hang silently, just lock up totally unresponsive, if I changed the clock speed it would run stable.
>> I finally figured out the problem and its actually quite simple.
>> On boot we set all the regulators initially to their lowest possible voltage, this in my case is too low to make the little cpu’s run reliably.
>> U-boot sets the lcpu voltage to 900mv and speed to 816Mhz, on boot we re-adjust the voltage to 750mv which is too low for my cpus to work reliably @ 816Mhz.
>> I’ve added support for the regulator-init-microvolt setting and set that to 900000mv as per spec in the DTS, and that solves the issue.
>> Now running all 6 cores with changeable frequencies and no problems what so ever.
>> Patches on request if needed…
> 
> This is -current I assume.  Do you have Xorg up?  My Pinebook Pro is
> sitting on the table waiting for debian-testing to transition from
> kernel 5.4 to 5.6 so that, possibly, maybe, X works again.
> 
> However, I'd ditch debian with prejudice if I could bring
> up X on the Pinebook Pro with FreeBSD.  No need for HW acceleration.
> I also don't care much about the camera, microphone, etc.

Yes this is -current. And no video drivers yet AFAIK.
This at least for me makes it a stable platform to work on, headless for now though, which makes progress a lot easier.
However if nobody else is working on it I will look into getting (simple) video going in the not too distant future, but time is sparse..

-Søren