kernel/linux.git/drivers/gpu/drm/tiny/cirrus.c, branch v6.6.133

drm/cirrus-qemu: Fix pitch programming

2025-07-06T09:00:14+00:00

commit 4bfb389a0136a13f0802eeb5e97a0e76d88f77ae upstream. Do not set CR1B[6] when programming the pitch. The bit effects VGA text mode and is not interpreted by qemu. [1] It has no affect on the scanline pitch. The scanline bit that is set into CR1B[6] belongs into CR13[7], which the driver sets up correctly. This bug goes back to the driver's initial commit. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://gitlab.com/qemu-project/qemu/-/blob/stable-9.2/hw/display/cirrus_vga.c?ref_type=heads#L1112 # 1 Fixes: f9aa76a85248 ("drm/kms: driver for virtual cirrus under qemu") Cc: Adam Jackson Cc: Dave Airlie Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: # v3.5+ Link: https://lore.kernel.org/r/20250328091821.195061-2-tzimmermann@suse.de Signed-off-by: Greg Kroah-Hartman

drm/cirrus: Use VGA macro constants to unblank

2023-03-13T09:37:09+00:00

Set the VGA bit for unblanking with macro constants instead of magic values. No functional changes. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-18-tzimmermann@suse.de

drm/cirrus: Store HW format/pitch in primary-plane state

2023-03-13T09:37:05+00:00

The hardware settings for color format and pitch are state of the primary plane. Store the values in the primary plane's state structure struct cirrus_primary_plane_state. Adapt all callers. All fields in struct cirrus_device are now considered immutable after initialization. Plane updates consider the difference between the old and the new plane state before updating format or pitch. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-17-tzimmermann@suse.de

drm/cirrus: Introduce struct cirrus_primary_plane_state

2023-03-13T09:37:02+00:00

The cirrus driver maintains plane state, format and pitch, in it's device structure. Introduce a plane state for the primary plane to store the values. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-16-tzimmermann@suse.de

drm/cirrus: Inline cirrus_check_size() into primary-plane atomic_check

2023-03-13T09:36:59+00:00

Inline the framebuffer size check into the primary plane's atomic_check cirrus_primary_plane_atomic_check(). No functional changes. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-15-tzimmermann@suse.de

drm/cirrus: Test mode against video-memory size in device-wide mode_valid

2023-03-13T09:36:55+00:00

Test a display mode against the available amount of video memory in struct drm_mode_config_funcs.mode_valid, which cirrus implements in cirrus_mode_config_mode_valid(). This helper tests display modes against device-wide limits. Remove the now-obsolete per-CRTC test. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-14-tzimmermann@suse.de

drm/cirrus: Remove size test from cirrus_fb_create()

2023-03-13T09:36:40+00:00

The DRM core implements a size check against the mode config's limits when creating a framebuffer. [1] Remove the unnecessary test from cirrus_fb_create() and remove the now-empty function. Create framebuffers with drm_gem_fb_create_with_dirty(). Signed-off-by: Thomas Zimmermann Link: https://elixir.bootlin.com/linux/v6.1/source/drivers/gpu/drm/drm_framebuffer.c#L287 # [1] Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-13-tzimmermann@suse.de

drm/cirrus: Remove format test from cirrus_fb_create()

2023-03-13T09:36:32+00:00

The DRM core implements a format check when setting a framebuffer for a plane. [1] Remove the unnecessary test from cirrus_fb_create(). Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://elixir.bootlin.com/linux/v6.1/source/drivers/gpu/drm/drm_atomic.c#L629 # [1] Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-12-tzimmermann@suse.de

drm/cirrus: Inline cirrus_fb_blit_rect()

2023-03-13T09:36:28+00:00

Inline cirrus_fb_blit_rect into its only caller. While at it, update the code to use IOSYS_MAP_INIT_OFFSET(), which is the ideomatic way of initializing struct iosys_map with an offset. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-11-tzimmermann@suse.de

drm/cirrus: Enable damage clipping on primary plane

2023-03-13T09:36:24+00:00

Enable damage clipping on the primary plane and iterate over small areas of reported framebuffer damage. Avoid the overhead of permanent full-screen updates that cirrus currently implements. This problem is indicated by the warning drm_plane_enable_fb_damage_clips() not called in the kernel's log. Without damage clipping, drivers do full updates of the screen area. This is costly as many screen updates, such as cursor movement or command-line input, only change a small portion of the output. Damage clipping allows renderers to inform drivers about the changed areas. With the damage information known, cirrus now iterates over a list of change areas and only flushes those to the hardware's scanout buffer. Signed-off-by: Thomas Zimmermann Acked-by: Gerd Hoffmann Link: https://patchwork.freedesktop.org/patch/msgid/20230215161517.5113-10-tzimmermann@suse.de