Re: [PATCH 6/8] drm/i915: Allow up to 32KB stride on SKL+ "sprites"

Ville Syrjälä
2018-01-17T20:18:48Z

On Wed, Jan 10, 2018 at 02:03:21PM +0100, Daniel Vetter wrote:
> On Fri, Dec 22, 2017 at 09:22:29PM +0200, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >
> > SKL+ "sprites" no longer have 16KB max stride limit that earlier
> > platforms had. Bump up the limit to 32KB.
> >
> > Cc: Ben Widawsky <ben@bwidawsk.net>
> > Cc: Jason Ekstrand <jason@jlekstrand.net>
> > Cc: Daniel Stone <daniels@collabora.com>
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> > drivers/gpu/drm/i915/intel_sprite.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
> > index cb06acff283d..94188488db05 100644
> > --- a/drivers/gpu/drm/i915/intel_sprite.c
> > +++ b/drivers/gpu/drm/i915/intel_sprite.c
> > @@ -865,6 +865,7 @@ intel_check_sprite_plane(struct intel_plane *plane,
> > struct drm_rect *src = &state->base.src;
> > struct drm_rect *dst = &state->base.dst;
> > const struct drm_rect *clip = &state->clip;
> > + int max_stride = INTEL_GEN(dev_priv) >= 9 ? 32768 : 16384;
> > int hscale, vscale;
> > int max_scale, min_scale;
> > bool can_scale;
> > @@ -885,7 +886,7 @@ intel_check_sprite_plane(struct intel_plane *plane,
> > }
> >
> > /* FIXME check all gen limits */
> > - if (fb->width < 3 || fb->height < 3 || fb->pitches[0] > 16384) {
> > + if (fb->width < 3 || fb->height < 3 || fb->pitches[0] > max_stride) {
> > DRM_DEBUG_KMS("Unsuitable framebuffer for plane\n");
> > return -EINVAL;
>
> Since pre-gen9 sprites are special, and since we're already validating the
> overall sprite limits in intel_fb_pitch_limit I'd push this into a new if
> condition like
>
> if (gen < 9 && pichtes[0] > KB(16)) {
> DRM_DEBUG_KMS("Invalid stride\n");
> return -EINVAL;
> }

I think we'll want to clean up this mess by moving a lot of these
checks into platform specific code. We're also missing a bunch of
checks we should be doing (eg. cdclk vs. scaling limits on ilk-ivb).

>
> With or without that bikeshed:
>
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

--
Ville Syrjälä
Intel OTC