Commit 046a10f4 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/nouveau: Do not implement mode_set_base_atomic callback 



Remove the implementation of the CRTC helper mode_set_base_atomic
from nouveau. It pretends to provide mode setting for kdb debugging,
but has been broken for some time.

Kdb output has been supported only for non-atomic mode setting since
commit 9c79e0b1 ("drm/fb-helper: Give up on kgdb for atomic drivers")
from 2017.

While nouveau provides non-atomic mode setting for some devices, kdb
assumes that the GEM buffer object is at a fixed location in video
memory. This has not been the case since
commit 4a16dd9d ("drm/nouveau/kms: switch to drm fbdev helpers")
from 2022. Fbdev-ttm helpers use a shadow buffer with a movable GEM
buffer object. Triggering kdb does therefore not update the display.

Hence remove the whole kdb support from nouveau.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Acked-by: default avatarSimona Vetter <simona.vetter@ffwll.ch>
Acked-by: default avatarDaniel Thompson (RISCstar) <danielt@kernel.org>
Link: https://patch.msgid.link/20251125130634.1080966-3-tzimmermann@suse.de
parent f80e8944

drivers/gpu/drm/nouveau/dispnv04/crtc.c

+4 −20
Original line number Diff line number Diff line
@@ -837,7 +837,7 @@ nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b, 
static int

nv04_crtc_do_mode_set_base(struct drm_crtc *crtc,

			   struct drm_framebuffer *passed_fb,

			   int x, int y, bool atomic)

			   int x, int y)

{

	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);

	struct drm_device *dev = crtc->dev;
@@ -850,19 +850,12 @@ nv04_crtc_do_mode_set_base(struct drm_crtc *crtc, 
	NV_DEBUG(drm, "index %d\n", nv_crtc->index);



	/* no fb bound */

	if (!atomic && !crtc->primary->fb) {

	if (!crtc->primary->fb) {

		NV_DEBUG(drm, "No FB bound\n");

		return 0;

	}



	/* If atomic, we want to switch to the fb we were passed, so

	 * now we update pointers to do that.

	 */

	if (atomic) {

		drm_fb = passed_fb;

	} else {

	drm_fb = crtc->primary->fb;

	}



	nvbo = nouveau_gem_object(drm_fb->obj[0]);

	nv_crtc->fb.offset = nvbo->offset;
@@ -920,15 +913,7 @@ nv04_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y, 
	int ret = nv_crtc_swap_fbs(crtc, old_fb);

	if (ret)

		return ret;

	return nv04_crtc_do_mode_set_base(crtc, old_fb, x, y, false);

}



static int

nv04_crtc_mode_set_base_atomic(struct drm_crtc *crtc,

			       struct drm_framebuffer *fb,

			       int x, int y, enum mode_set_atomic state)

{

	return nv04_crtc_do_mode_set_base(crtc, fb, x, y, true);

	return nv04_crtc_do_mode_set_base(crtc, old_fb, x, y);

}



static void nv04_cursor_upload(struct drm_device *dev, struct nouveau_bo *src,
@@ -1274,7 +1259,6 @@ static const struct drm_crtc_helper_funcs nv04_crtc_helper_funcs = { 
	.commit = nv_crtc_commit,

	.mode_set = nv_crtc_mode_set,

	.mode_set_base = nv04_crtc_mode_set_base,

	.mode_set_base_atomic = nv04_crtc_mode_set_base_atomic,

	.disable = nv_crtc_disable,

	.get_scanout_position = nouveau_display_scanoutpos,

};