Hi, > > R600+ supports bigendian framebuffer formats, so no byteswapping on > > access is needed. Not sure whenever that includes 16bpp formats or > > whenever this is limited to the 8 bit-per-color formats [...] > > It includes 16bpp. Looking at > drivers/gpu/drm/radeon/atombios_crtc.c:dce4_crtc_do_set_base(), it sets > up byte-swapping for all multi-byte formats, so it effectively treats > all those formats as if they had DRM_FORMAT_BIG_ENDIAN set. > If the radeon (and amdgpu) driver were to be changed to use > drm_mode_legacy_fb_format_he for >= R600, that must also handle 16 bpp, > which requires DRM_FORMAT_BIG_ENDIAN. So I still don't see how that can > be removed or even deprecated. Ok. Dropped patch #1. Updated patch #2 to include all formats returned by drm_mode_legacy_fb_format, and also renamed them to DRM_FORMAT_HOST_*. Question is how to go forward with patch #3. I'd prefer to not add drm_mode_legacy_fb_format_he if possible. Is there a chance to adapt the radeon and nvidia drivers to a fixed drm_mode_legacy_fb_format function (returning be formats on be) without invasive changes? Given they both treat formats as if they had DRM_FORMAT_BIG_ENDIAN set this could (with the help of the extended patch #2) be a simple s/DRM_FORMAT_/DRM_FORMAT_HOST/ at the right places ... Michael? Ilia? cheers, Gerd
