Hi, On 25/03/2020 10:04, Simon Ser wrote: > On Wednesday, March 25, 2020 9:50 AM, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote: > >> Amlogic uses a proprietary lossless image compression protocol and format >> for their hardware video codec accelerators, either video decoders or >> video input encoders. >> >> This introduces the Scatter Memory layout, means the header contains IOMMU >> references to the compressed frames content to optimize memory access >> and layout. >> >> In this mode, only the header memory address is needed, thus the content >> memory organization is tied to the current producer execution and cannot >> be saved/dumped neither transferrable between Amlogic SoCs supporting this >> modifier. > > I don't think this is suitable for modifiers. User-space relies on > being able to copy a buffer from one machine to another over the > network. It would be pretty annoying for user-space to have a blacklist > of modifiers that don't work this way. > > Example of such user-space: > https://gitlab.freedesktop.org/mstoeckl/waypipe/ > I really understand your point, but this is one of the use-cases we need solve. This is why I split the fourcc patch and added an explicit comment. Please point me a way to display such buffer, the HW exists, works like that and it's a fact and can't change. It will be the same for secure zero-copy buffers we can't map from userspace, but only the HW decoder can read/write and HW display can read. We need a solution for those if we want embedded and secure products to be supported upstream, otherwise they will stay in an obscure off-tree linux tree and for example AOSP support (which will support these secure video buffers) will use these vendor specific hacks. Neil _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
