drm/ast: Only set VGA SCREEN_DISABLE bit in CRTC code

Browse source

The SCREEN_DISABLE bit controls scanout from display memory. The bit
affects all planes, so set it only in the CRTC's atomic enable and
disable functions.

A number of bugs affect this fix. First of all, ast_set_std_regs()
tries to set VGASR1 except for the SD bit. But the read bitmask is
invert, so it preserves anything except the SD bit. Fix this by
re-inverting the read mask.

The second issue is that primary-plane and CRTC helpers modify the
SD bit. The bit controls scanout for all planes, primary and HW
cursor, so set it only in the CRTC code.

Further add a constant to represent the SD bit in VGASR1. Keep the
plane's atomic_disable around to make the DRM framework happy.

v2:
- fix typos in commit message

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240627153638.8765-7-tzimmermann@suse.de

...

This commit is contained in:

Thomas Zimmermann 2024-06-27 17:27:51 +02:00

parent bb5367d17e

commit 171b357d18

2 changed files with 8 additions and 7 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

14

drivers/gpu/drm/ast/ast_mode.c

View file

1

drivers/gpu/drm/ast/ast_reg.h

View file