Re: [PATCH 1/5] clk: inherit clocks enabled by bootloader

Rob Clark
2019-07-01T19:05:59Z

On Mon, Jul 1, 2019 at 11:25 AM Eric Anholt <eric@anholt.net> wrote:
>
> Rob Clark <robdclark@gmail.com> writes:
>
> > From: Rob Clark <robdclark@chromium.org>
> >
> > The goal here is to support inheriting a display setup by bootloader,
> > although there may also be some non-display related use-cases.
> >
> > Rough idea is to add a flag for clks and power domains that might
> > already be enabled when kernel starts, and which should not be
> > disabled at late_initcall if the kernel thinks they are "unused".
> >
> > If bootloader is enabling display, and kernel is using efifb before
> > real display driver is loaded (potentially from kernel module after
> > userspace starts, in a typical distro kernel), we don't want to kill
> > the clocks and power domains that are used by the display before
> > userspace starts.
> >
> > Signed-off-by: Rob Clark <robdclark@chromium.org>
>
> Raspberry Pi is carrying downstream hacks to do similar stuff, and it
> would be great to see CCF finally support this.

yeah, both this and the multiple-possible-panel thing are a big source
of downstream hacks on basically every android device too.. :-/

it certainly would be nice to have upstream solutions for these
problems to give downstream hacks a reason not to exist

BR,
-R