Re: [PATCH 3/6] drm: fourcc byteorder: add bigendian support to drm_mode_legacy_fb_format

On 24/04/17 03:25 PM, Gerd Hoffmann wrote:

Return correct fourcc codes on bigendian. Drivers must be adapted to this change.

Signed-off-by: Gerd Hoffmann kraxel@redhat.com

Just to reiterate, this won't work for the radeon driver, which programs the GPU to use (effectively, per the current definition that these are little endian GPU formats) DRM_FORMAT_XRGB8888 with pre-R600 and DRM_FORMAT_BGRX8888 with >= R600.

+#ifdef __BIG_ENDIAN

• switch (bpp) {
• case 8:

• fmt = DRM_FORMAT_C8;
  

• break;
  

• case 24:

• fmt = DRM_FORMAT_BGR888;
  

• break;
  

BTW, endianness as a concept cannot apply to 8 or 24 bpp formats.