Re: [PATCH v5 0/4] drm/nouveau: GSP runtime PM fixes

[David Airlie]

On Sat, Aug 15, 2026 at 5:45 AM Lyude Paul <lyude@xxxxxxxxxx> wrote:
>
> Runtime suspend/resume has been notoriously flakey since we started
> using the R570 GSP firmware, and possibly was also flakey for some time
> when we introduced GSP support initially.
>
> These fixes get runtime PM to be dramatically more stable then it was
> before. Unfortunately even with this patch series, there are still some
> remaining issues that need to be fixed. These likely stem from the
> currently different code path that we need to take with these fixes in
> order to get suspend/resume working.
>
> While we're making progress in understanding what exactly we're doing
> differently from OpenRM that makes this the case, it will likely take us
> a while before we actually have things working well enough to copy what
> OpenRM does. Taking precisely the same path that OpenRM takes however,
> will require some additional work - and at the very least these fixes do
> appear to get suspend/resume and runtime PM working the vast majority of
> the time.
>
> Thanks for nvidia for providing context into what all of these various
> flags and settings do!

While I did not expect the ending to be make the magic sleep magicer,
I appreciate I introduced the magic sleep and got to the same point in
trying to explain it, and failed for it to make any sense.

For the series:

Reviewed-by: Dave Airlie <airlied@xxxxxxxxxx>

>
> Previous version of this patch series:
>
>   https://patchwork.freedesktop.org/series/169457/
>
> Patch-wide changes:
> * Add magic sleep, this seems to get things stable - but boy I wish I
>   could figure out why.
>
> Lyude Paul (4):
>   Revert "nouveau/gsp: fix suspend/resume regression on r570 firmware"
>   drm/nouveau/gsp/r570: Set GcOff = 0 in fbsr
>   drm/nouveau/gsp/r570: Enable S/R Display workaround in GSP
>   drm/nouveau/gsp: Increase delay for magic sleep in r535_gsp_fini()
>
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/fbsr.c    | 2 +-
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/gsp.c     | 8 ++++++--
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/fbsr.c    | 8 ++++----
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/gsp.c     | 3 ++-
>  .../gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/nvrm/gsp.h    | 8 ++++++++
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/rm.h           | 2 +-
>  6 files changed, 22 insertions(+), 9 deletions(-)
>
>
> base-commit: f29ab62f7ed55eae7b246bb535ede56d3b338674
> --
> 2.55.0
>