[Intel-gfx] [PATCH (resend) 1/3] drm/i915: Ignore previous watermarks on ILK if inherited

[Daniel Vetter]

On Wed, Nov 08, 2017 at 05:09:33PM +0100, Maarten Lankhorst wrote:
> Op 08-11-17 om 16:41 schreef Daniel Vetter:
> > On Wed, Nov 08, 2017 at 10:29:20AM +0100, Maarten Lankhorst wrote:
> >> Fixes the following error when fastset is enabled, caught by CI:
> >>
> >> [drm:ilk_validate_wm_level.part.8 [i915]] Sprite WM0 too large 56 (max 0)
> >> [drm:ilk_validate_pipe_wm [i915]] LP0 watermark invalid
> >> [drm:intel_crtc_atomic_check [i915]] No valid intermediate pipe watermarks are possible
> >>
> >> Triggered on debugfs_test.read_all_entries, but could have been any igt
> >> test depending on ordering.
> >>
> >> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> > So I'm no expert on this, but why is this not needed for g4x and vlv
> > intermediate wm? I think the commit message should explain that. I think
> > it should also explain why simply shutting the above warnings up is safe.
> >
> > I think once that's fixed I understand why we need this and why it works,
> > but probably better to get an Ack from Ville to make sure.
> > -Daniel
> True, reason it's not needed there is because intermediate calculation can't fail.
> And yeah best say because BIOS wm are bogus here.

Ok, with that (maybe a bit more verbose) explained in the commit message:

Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

> >> ---
> >>  drivers/gpu/drm/i915/intel_pm.c | 4 +++-
> >>  1 file changed, 3 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> >> index 46440e2ecb33..9e8a0a9cac02 100644
> >> --- a/drivers/gpu/drm/i915/intel_pm.c
> >> +++ b/drivers/gpu/drm/i915/intel_pm.c
> >> @@ -3137,7 +3137,9 @@ static int ilk_compute_intermediate_wm(struct drm_device *dev,
> >>  	 * and after the vblank.
> >>  	 */
> >>  	*a = newstate->wm.ilk.optimal;
> >> -	if (!newstate->base.active || drm_atomic_crtc_needs_modeset(&newstate->base))
> >> +	if (!newstate->base.active ||
> >> +	    drm_atomic_crtc_needs_modeset(&newstate->base) ||
> >> +	    oldstate->base.mode.private_flags & I915_MODE_FLAG_INHERITED)
> >>  		return 0;
> >>  
> >>  	a->pipe_enabled |= b->pipe_enabled;
> >> -- 
> >> 2.15.0
> >>
> >> _______________________________________________
> >> Intel-gfx mailing list
> >> Intel-gfx at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch