ath11k: QCA6390 on Dell XPS 13 and kernel crashes

[Stephen Liang]

Okay, I installed ath11k-qca6390-bringup (6244933dd) and did notice
lockups occurring. In fact, I found a reproducible way to lock up the
system:

1. Turn off WiFi
2. Reboot system
3. Login
4. Turn on WiFi

If you perform those steps, the system will lock on
ath11k-qca6390-bringup, dmesg: https://i.imgur.com/0XExack.jpg

On 59c6d02 + revert of 7fef431be9c9, the firmware will crash but the
system will not lock up. dmesg: https://pastebin.com/raw/hH0HyWVx

If you keep WiFi on, i.e. the system is automatically connected to
WiFi on boot, then on the ath11k-qca6390-bringup tag, it randomly
freezes. On 59c6d02, it seems to be fairly stable so long as I do not
turn off/turn on WiFi. I can bisect based on the reproducible steps in
the next couple days if nobody else comes up with something first.

On Wed, Dec 9, 2020 at 7:07 PM Stephen Liang <stephenliang7 at gmail.com> wrote:
>
> > Thanks, good to know. On what platform is this, can you share more details? Is it the new Dell XPS 13 9310 or something else?
>
> Yes, this is the XPS 13 9310.
>
> > I recommend using ath11k-qca6390-bringup branch, it has quite a few
> fixes:
>
> Let me give that a shot, perhaps if I can reproduce the same issues
> the others have been seeing I could start a bisect as well.
>
> My uptime is now at 2 days with Fedora Rawhide kernel 5.10.0-0.rc6
> with commit 59c6d022df8efb450f82d33dd6a6812935bd022f and a revert of
> 7fef431be9c9 patched in. I'm not experiencing any of the stalls or
> crashes that others have been mentioning and I have been able to
> suspend/resume consistently. No issues with power being plugged and
> unplugged either. Happy to help provide details if anybody needs any.
>
> > You mean that the reboot stalls and you need to turn off the laptop using power button?
>
> Actually, with the previously mentioned commit combination, I was able
> to shutdown and reboot successfully as well.