[Intel-gfx] [PATCH 7/7] drm/i915: check for strange pfit pipe assignemnt on ivb/hsw

[Paulo Zanoni]

2013/6/1 Daniel Vetter <daniel.vetter at ffwll.ch>:
> Panel fitters on ivb/hsw are not created equal since not all of them
> support the new high-quality upscaling mode. To offset this the hw
> allows us to freely assign the pfits to pipes.
>
> Since our code currently doesn't support this we might fall over when
> taking over firmware state. So check for this case and WARN about it.
> We can then improve the code once we've hit this in the wild. Or once
> we decide to support the improved upscale modes, though that requires
> global arbitrage of modeset resources across crtcs.
>
> Suggested-by: Mika Kuoppala <mika.kuoppala at intel.com>
> Cc: Mika Kuoppala <mika.kuoppala at intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 432e699..2b6e141 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -5806,6 +5806,14 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
>         if (tmp & PF_ENABLE) {
>                 pipe_config->pch_pfit.pos = I915_READ(PF_WIN_POS(crtc->pipe));
>                 pipe_config->pch_pfit.size = I915_READ(PF_WIN_SZ(crtc->pipe));
> +
> +               /* We currently do not free assignements of panel fitters on
> +                * ivb/hsw (since we don't use the higher upscaling modes which
> +                * differentiates them) so just WARN about this case for now. */
> +               if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) {

Or just check for IS_GEN7 or, to be future-proof, check for "gen >= 7"
since there's a higher chance that newer gens will be similar to gen 7
instead of the previous ones.

Anyway: Reviewed-by: Paulo Zanoni <paulo.r.zanoni at intel.com>

> +                       WARN_ON((tmp & PF_PIPE_SEL_MASK_IVB) !=
> +                               PF_PIPE_SEL_IVB(crtc->pipe));
> +               }
>         }
>  }
>
> --
> 1.7.11.7
>



-- 
Paulo Zanoni