On Mon, Mar 11, 2019 at 09:39:28AM -0700, Alyssa Rosenzweig wrote: > > You might want to re-use the exisiting modifier > > AFBC_FORMAT_MOD_BLOCK_SIZE_16x16. > > > > I would suggest you to have a look at the exisiting AFBC modifiers > > (denoted by AFBC_FORMAT_MOD_XXX ) and let us know if there is > > something you cannot reuse. > > So, the "tiled" format in question (that Qiang needs to import/export > BOs in) is *uncompressed* but tiled with an Arm-internal format (for the > GPUs). Here's a software implementation for encoding this format: > https://cgit.freedesktop.org/mesa/mesa/tree/src/gallium/drivers/panfrost/pan_swizzle.c > ok I understood now. In this case, please ignore my suggestion. > For Midgard/Bifrost, we use this tiling internally for uploading bitmap > textures, but we only render to AFBC (or linear). So for Panfrost, we'll > always be importing/exporting AFBC buffers, never uncompressed tiled.
I am not a gpu guy so can't comment at the moment. > But Utgard does not seem to support AFBC (?), so Qiang needs the > uncompressed tiled for the same purpose Panfrost uses AFBC. > > Is it possible that this is the same tiling used internally by > AFBC_FORMAT_MOD_BLOCK_SIZE_16x16, only without any compression? AFBC is > blackbox for us, so this isn't something we can figure out ourselves, > but that influences whether it's appropriate to reuse the modifier. If > this is the same tiling scheme, perhaps that's the answer. If it's not > (I don't know how AFBC tiling works), we probably do need a separate > modifier to avoid confusion. > AFBC_FORMAT_MOD_BLOCK_SIZE_16x16 denotes the superblock size to be used only in case of AFBC buffers. For non compressed tiled format, none of the AFBC_FORMAT_MOD_XXX should be used. However, I would like you to review my patch series (https://patchwork.freedesktop.org/series/53395/) to see if we have the same understanding. > Thanks, > > Alyssa > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
