Re: [RFC] drm/msm/adreno: Balance pm_runtime enable

From: Johan Hovold
Date: Wed Feb 22 2023 - 06:08:05 EST


On Fri, Feb 10, 2023 at 08:10:00AM -0800, Rob Clark wrote:
> On Fri, Feb 3, 2023 at 10:12 AM Bjorn Andersson
> <quic_bjorande@xxxxxxxxxxx> wrote:
> >
> > When any of the components in the mdss hierarchy fails to bind,
> > previously bound components are being unbound again.
> >
> > One such case happens when the DP controller fails to find its bridge or
> > panel, where adreno_unbind() will be invoked without adreno_load_gpu()
> > being called to invoke pm_runtime_enable().
> >
> > The result is that once everything is bound the pm_runtime_get_sync()
> > call find the power-domain to have a positive disable_depth, fails
> > with -EACCESS and prevents the GPU device to be powered up.
> >
> > Move the pm_runtime_enable() to adreno_bind(), in order to balance it
> > with any calls to adreno_unbind().
>
> I think instead we want to move where the pm_runtime_disable() is..
> since pm_runtime_enable() was moved because we can't actually enable
> runpm until we have GMU firmware

Here's a fix for this issue which does not move pm_runtime_enable() from
first open():

https://lore.kernel.org/lkml/20230221101430.14546-1-johan+linaro@xxxxxxxxxx/

Johan