kernel/linux.git/drivers/gpu/drm/sysfb/drm_sysfb_modeset.c, branch v6.19.11

drm/sysfb: Use new CRTC state in begin_fb_access

2025-10-23T08:36:14+00:00

Retrieve the CRTC's new state with drm_atomic_get_new_crtc_state() in drm_sysfb_plane_helper_begin_fb_access(). The blit function might be incorrect otherwise. Signed-off-by: Thomas Zimmermann Fixes: cb71de092553 ("drm/sysfb: Lookup blit function during atomic check") Reported-by: Ville Syrjälä Closes: https://lore.kernel.org/dri-devel/aPJrs7_u8KcalNsC@intel.com/ Cc: Thomas Zimmermann Cc: Javier Martinez Canillas Cc: dri-devel@lists.freedesktop.org Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20251020125227.41308-1-tzimmermann@suse.de

drm/sysfb: Lookup blit function during atomic check

2025-09-23T13:06:06+00:00

Some configurations of sysfb outputs require format conversion from framebuffer to scanout buffer. It is a driver bug if the conversion helper is missing, yet it might happen on odd scanout formats. The old code, based on drm_fb_blit(), only detects this situation during the commit's hardware update, which is too late to abort the update. Lookup the correct blit helper as part of the check phase. Then store it in the sysfb plane state. Allows for detection of a missing helper before the commit has started. Also avoids drm_fb_blit()'s large switch statement on each updated scanline. Only a single lookup has to be done. The lookup is in drm_sysfb_get_blit_func(), which only tracks formats supported by sysfb drivers. The lookup happens in sysfb's begin_fb_access helper instead of its atomic_check helper. This allows vesadrm, and possibly other drivers, to implement their own atomic_check without interfering with blit lookups. Vesadrm implements XRGB8888 on top of R8 formats with the help of the atomic_check. Doing the blit lookup in begin_fb_access then always uses the correct CRTC format on all drivers. v2: - vesadrm: use drm_sysfb_plane_helper_begin_fb_access() - fix type in commit description (Javier) Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20250918154207.84714-3-tzimmermann@suse.de

drm/sysfb: Add custom plane state

2025-09-23T13:06:05+00:00

The plane-state type struct drm_sysfb_plane_state will store the helper for blitting to the scanout buffer. v2: - add variable for duplicated shadow-plane state (Javier) - fix build error Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20250918154207.84714-2-tzimmermann@suse.de

drm/sysfb: Remove double assignment to pointer crtc_state

2025-09-04T07:26:39+00:00

The declaration of pointer crtc_state includes an assignment to crtc_state. The double assignment of crtc_state is redundant and can be removed. Fixes: 061963cd9e5b ("drm/sysfb: Blit to CRTC destination format") Signed-off-by: Colin Ian King Reviewed-by: Thomas Zimmermann Signed-off-by: Thomas Zimmermann Link: https://lore.kernel.org/r/20250903083106.2703580-1-colin.i.king@gmail.com

drm/sysfb: Do not deref unexisting CRTC state in atomic_disable

2025-08-27T12:09:58+00:00

Do not access CRTC state in drm_sysfb_plane_helper_atomic_disable(). Use format from sysfb device for clearing scanout buffer. This is the behavior from before commit 061963cd9e5b ("drm/sysfb: Blit to CRTC destination format"). When being disabled, the plane has no associated CRTC. Trying to deref the format pointer results in a segmentation fault. An example stack track is shown below. [ 58.948915] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000023: 0000 [#1] SMP KASAN PTI [ 58.959971] KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] [...] [ 58.979308] RIP: 0010:drm_sysfb_plane_helper_atomic_disable+0x1af/0x520 [...] [ 59.084227] Call Trace: [ 59.086682] [ 59.088793] ? __pfx_drm_sysfb_plane_helper_atomic_disable+0x10/0x10 [ 59.095155] ? crtc_disable+0xf2/0x5a0 [ 59.098920] drm_atomic_helper_commit_planes+0x848/0x1030 [ 59.104336] drm_atomic_helper_commit_tail+0x41/0xb0 [ 59.109316] commit_tail+0x204/0x330 [ 59.112903] drm_atomic_helper_commit+0x242/0x2e0 [ 59.117618] ? __pfx_drm_atomic_helper_commit+0x10/0x10 [ 59.122851] drm_atomic_commit+0x1e1/0x290 [ 59.126957] ? drm_atomic_add_affected_connectors+0x266/0x330 [ 59.132714] ? __pfx_drm_atomic_commit+0x10/0x10 [ 59.137343] ? __pfx___drm_printfn_info+0x10/0x10 [ 59.142058] ? drm_atomic_set_crtc_for_connector+0x436/0x630 [ 59.147729] atomic_remove_fb+0x631/0x920 [ 59.151751] ? save_trace+0xcf/0x180 [ 59.155343] ? __pfx_atomic_remove_fb+0x10/0x10 [ 59.159890] ? __pfx___drm_dev_dbg+0x10/0x10 [ 59.164173] drm_framebuffer_remove+0x19a/0x710 Signed-off-by: Thomas Zimmermann Fixes: 061963cd9e5b ("drm/sysfb: Blit to CRTC destination format") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14874 Cc: Thomas Zimmermann Cc: Javier Martinez Canillas Cc: dri-devel@lists.freedesktop.org Reviewed-by: Maarten Lankhorst Link: https://lore.kernel.org/r/20250826145044.954396-1-tzimmermann@suse.de

drm/sysfb: Blit to CRTC destination format

2025-08-26T07:54:17+00:00

Use the color format stored in struct drm_sysfb_crtc_state for color-format conversion instead of the scanout-buffer format announced by firmware. Currently, both values are identical. This will allow drivers to modify the CRTC's input format to a certain extend. Specifically, vesadrm will be able to display RGB framebuffers when the scanout buffer is of C8 format. With color- format conversion to RGB332 and correct setup of the C8 palette, displaying XRGB8888-based buffers under C8 can be achieved. v2: - refer to RGB332 as CRTC input format Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20250714151513.309475-5-tzimmermann@suse.de

drm/format-helper: Move drm_fb_build_fourcc_list() to sysfb helpers

2025-06-18T08:46:03+00:00

Only sysfb drivers use drm_fb_build_fourcc_list(). Move the function to sysfb helpers and rename it accordingly. Update drivers and tests. v3: - update naming in tests v2: - select DRM_SYSFB_HELPER (kernel test robot) Signed-off-by: Thomas Zimmermann Reviewed-by: José Expósito Acked-by: Maxime Ripard Acked-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20250616083846.221396-4-tzimmermann@suse.de

drm/sysfb: Split source file

2025-04-14T08:16:12+00:00

Split drm_sysfb_helper.c into two source files. There's now one source file for the mode-setting pipeline and one source file for module meta data. Prepares for adding additional source code to sysfb helpers. v2: - fix typo in commit message (Javier) Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20250410083834.10810-2-tzimmermann@suse.de