linux.git/drivers/video/fbdev/core/cfbimgblt.c, branch for-next

fbdev: Warn on incorrect framebuffer access

2023-11-29T11:20:50+00:00

Test in framebuffer read, write and drawing helpers if FBINFO_VIRTFB
has been set correctly. Framebuffers in I/O memory should only be
accessed with the architecture's respective helpers. Framebuffers
in system memory should be accessed with the regular load and
store operations. Presumably not all drivers get this right, so we
now warn about it.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Link: https://patchwork.freedesktop.org/patch/msgid/20231127131655.4020-32-tzimmermann@suse.de

fbdev: Fix cfb_imageblit() for arbitrary image widths

2022-03-17T19:26:57+00:00

Commit 0d03011894d2 ("fbdev: Improve performance of cfb_imageblit()")
broke cfb_imageblit() for image widths that are not aligned to 8-bit
boundaries. Fix this by handling the trailing pixels on each line
separately. The performance improvements in the original commit do not
regress by this change.

Signed-off-by: Thomas Zimmermann 
Fixes: 0d03011894d2 ("fbdev: Improve performance of cfb_imageblit()")
Reviewed-by: Javier Martinez Canillas 
Acked-by: Daniel Vetter 
Tested-by: Marek Szyprowski 
Reported-by: Marek Szyprowski 
Cc: Thomas Zimmermann 
Cc: Javier Martinez Canillas 
Cc: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220313192952.12058-3-tzimmermann@suse.de

fbdev: Improve performance of cfb_imageblit()

2022-03-02T19:22:33+00:00

Improve the performance of cfb_imageblit() by manually unrolling
the inner blitting loop and moving some invariants out. The compiler
failed to do this automatically. This change keeps cfb_imageblit()
in sync with sys_imagebit().

A microbenchmark measures the average number of CPU cycles
for cfb_imageblit() after a stabilizing period of a few minutes
(i7-4790, FullHD, simpledrm, kernel with debugging).

cfb_imageblit(), new: 15724 cycles
cfb_imageblit(): old: 30566 cycles

In the optimized case, cfb_imageblit() is now ~2x faster than before.

v3:
	* fix commit description (Pekka)

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220223193804.18636-5-tzimmermann@suse.de

fbdev: Remove trailing whitespaces from cfbimgblt.c

2022-03-02T19:22:06+00:00

Fix coding style. No functional changes.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220223193804.18636-4-tzimmermann@suse.de

fbdev: move fbdev core files to separate directory

2014-04-17T05:10:19+00:00

Instead of having fbdev framework core files at the root fbdev
directory, mixed with random fbdev device drivers, move the fbdev core
files to a separate core directory. This makes it much clearer which of
the files are actually part of the fbdev framework, and which are part
of device drivers.

Signed-off-by: Tomi Valkeinen 
Acked-by: Laurent Pinchart 
Acked-by: Geert Uytterhoeven 
Acked-by: Rob Clark 
Acked-by: Jingoo Han 
Acked-by: Daniel Vetter