On Wed, 27 Mar 2013 23:41:55 +0100 Daniel Vetter <daniel.vetter at ffwll.ch> wrote: > On Wed, Mar 27, 2013 at 10:28 PM, Jesse Barnes <jbarnes at virtuousgeek.org> wrote: > > I had to double check this against 9/13... I guess the order will be > > clearer with the actual code as opposed to patches. > > > > But won't these override the pipe_config bpp we set in > > pipe_config_set_bpp()? Why bother setting it there if each of the > > encoders will set it themselves, and the real comparison is against > > the plane bpp? And doesn't that mean we'd need to set pipe_config->bpp > > in the DP version too? > > The pipe_bpp we set from the planes is the proposed one, used when > nothing else overrides it. Then encoders can come around and add in > their opinion about what's possible. Note that encoders want to know > which pipe_bpp is the proposed one (from looking just at the plane) to > make their own decision. E.g. hdmi wants to updither 10bpc to 12bpc > (if possible) since it doesn't support 10bpc natively. Whereas DP only > ever down-dithers. > > This way we gain a notch more flexibility in handling bpp. > > My auto-fdi dither work which is based on top of this goes one step > further and checks (after plane/pipe/encoder all had their say) > whether it actually fits into the fdi link. If it doesn't fit it tries > to dither down. If that's possible we'll restart the pipe_config > arbitrage, but with the new proposed pipe_bpp plus a flag telling > everyone that they'll get shot if they try to increase bw > requirements. > > > Maybe I've been looking at this too hard and I've just confused > > myself... > > Maybe it's a bit overdesigned ;-) Ok it makes some sense... though maybe if we passed down the plane bpp directly we'd be able to avoid some of the re-calc stuff in your FDI dither patch. We can always improve it after it lands and becomes clearer. Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org> -- Jesse Barnes, Intel Open Source Technology Center
