Hi Daniel,
On Wed, Nov 23, 2022 at 5:57 PM Daniel Vetter <daniel@xxxxxxxx> wrote:
On Wed, Nov 23, 2022 at 05:43:10PM +0100, Geert Uytterhoeven wrote:
As of commit eae06120f1974e1a ("drm: refuse ADDFB2 ioctl for broken
bigendian drivers"), drivers must set the
quirk_addfb_prefer_host_byte_order quirk to make the drm_mode_addfb()
compat code work correctly on big-endian machines.
While that works fine for big-endian XRGB8888 and ARGB8888, which are
mapped to the existing little-endian BGRX8888 and BGRA8888 formats, it
does not work for big-endian XRGB1555 and RGB565, as the latter are not
listed in the format database.
Fix this by adding the missing formats. Limit this to big-endian
platforms, as there is currently no need to support these formats on
little-endian platforms.
Fixes: 6960e6da9cec3f66 ("drm: fix drm_mode_addfb() on big endian machines.")
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
v2:
- Use "DRM_FORMAT_foo | DRM_FORMAT_BIG_ENDIAN" instead of
"DRM_FORMAT_HOST_foo",
- Turn into a lone patch, as all other patches from series
https://lore.kernel.org/r/cover.1657300532.git.geert@xxxxxxxxxxxxxx
were applied to drm-misc/for-linux-next.
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -190,6 +190,10 @@ const struct drm_format_info *__drm_format_info(u32 format)
{ .format = DRM_FORMAT_BGRA5551, .depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
{ .format = DRM_FORMAT_RGB565, .depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_BGR565, .depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+#ifdef __BIG_ENDIAN
Why do we need the #ifdef here? Iirc some hw has big endian flags in the
scanout registers, so could supprt this unconditionally if there's no
#ifdef around the format defines. Some drivers might then also want a
DRM_FORMAT_FOO_BE define to simplify tables and stuff, but that's more a
bikeshed.
"Limit this to big-endian platforms, as there is currently no need
to support these formats on little-endian platforms."
Will anyone make use of this? In theory, all of the 16-bpp formats
can have a big-endian counterpart.
I seem to be the first one running into this ;-)
+ { .format = DRM_FORMAT_XRGB1555 | DRM_FORMAT_BIG_ENDIAN, .depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+ { .format = DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN, .depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+#endif
{ .format = DRM_FORMAT_RGB888, .depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_BGR888, .depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_XRGB8888, .depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
