On Wed, Mar 1, 2023 at 4:31 PM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote: > Add fbdev emulation that is optimized for DMA helpers, as used by most > drivers. It operates directly on GEM DMA buffers in system memory. > Memory pages are mmap'ed directly to userspace. No implicit shadow > buffers need to be allocated; as can happen with the generic fbdev > emulation. Convert drivers that fulfil the requirements. > > Tested with fbcon and IGT on vc4. > > Future direction: providing a dedicated fbdev emulation for GEM DMA > helpers will allow us to remove this case from the generic fbdev code. > The latter can then be simplified. 1) I love your work. 2) Why isn't this DRM driver changed? drivers/gpu/drm/mcde/mcde_drv.c AFAICT it also uses GEM buffers in system memory. 3) This one: drivers/gpu/drm/pl111/pl111_drv.c is also very similar, but can sometimes use a dedicated RAM memory for allocations using CMA, does that make it not a candidate? They aren't much different in how they work from the TVE200. Yours, Linus Walleij
