https://bugs.freedesktop.org/show_bug.cgi?id=77533
--- Comment #12 from vebveb@hotmail.fr --- I have tested to force to go to the fallback only before calling si_dma_copy_tile, to test if si_dma_copy_buffer was working.
I didn't notice any glitch or tiling problem with heaven, but I don't know if si_dma_copy_buffer is actually used or not.