Re: [PATCH] soc/tegra: pmc: Fix "scheduling while atomic"

From: Dmitry Osipenko
Date: Thu May 05 2016 - 10:24:34 EST


Hello, Jon!

On 05.05.2016 16:17, Jon Hunter wrote:

Thanks for the report. I have been unable to reproduce this, but then I
don't see my tegra20 entering LP2 during cpuidle. I did force my tegra20
into LP2 during suspend which will exercise the same code but I did not
trigger this either. However, from looking at the code it does appear
that we could hit this.


As I wrote before, it's quite difficult to reproduce.


Ideally, it would be great if we did not need to add another custom API
for this, but I did not find anything in the CCF that would allow us to
avoid but that was only a quick look. However, we could ask the CCF folks.


Yes, CCF doesn't expose locked API. Code should be designed to avoid it.

What I plan to do next is to understand if the pclk is likely to change.
I know that it comes from one of the plls but I am not sure if we ever
change the rate. If not we may be able to move this to probe time and
avoid this.


That's reasonable, I'd also take a look at it. Thanks for the comment!

--
Dmitry