Messages in this thread | | | From | Eric Anholt <> | Subject | Re: [PATCH RESEND] drm/vc4: Make sure to emit a tile coordinates between two MSAA loads. | Date | Fri, 22 Mar 2019 14:28:04 -0700 |
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Paul Kocialkowski <paul.kocialkowski@bootlin.com> writes:
> Hi, > > Le mercredi 06 février 2019 à 15:25 -0800, Eric Anholt a écrit : >> The HW only executes a load once the tile coordinates packet happens, >> and only tracks one at a time, so by emitting our two MSAA loads back >> to back we would end up with an undefined color or Z buffer. > > This change deals with things that I'm not very familiar with, but here > is my take on what is happening here: > > - When we have to do more than a single load in the same render command > list, we need to send out tile coordinates and a dummy store in between > the two, because of internal architecture requirements of the GPU; > - We're dealing with the color buffer first and then the z-stencil > buffer; > - As a result, we need to issue that dummy store in the block handling > the z-stencil, if there was a previous color load in the rcl; > - We previously only did that for non-MSAA z-stencil buffers (without > the FULL_RES flag); > - The same thing actually needs to be done for the MSAA case too, as > the reason why we need that dummy store also applies to MSAA loads. > > If my understanding is correct, then consider this: > Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
This is all correct. Thanks! [unhandled content-type:application/pgp-signature] | |