Commit a60ccade authored Apr 11, 2024 by Zack Rusin

drm/vmwgfx: Fix crtc's atomic check conditional

The conditional was supposed to prevent enabling of a crtc state
without a set primary plane. Accidently it also prevented disabling
crtc state with a set primary plane. Neither is correct.

Fix the conditional and just driver-warn when a crtc state has been
enabled without a primary plane which will help debug broken userspace.

Fixes IGT's kms_atomic_interruptible and kms_atomic_transition tests.

Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Fixes: 06ec4190 ("drm/vmwgfx: Add and connect CRTC helper functions")
Cc: Broadcom internal kernel review list <bcm-kernel-feedback-list@broadcom.com>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.12+
Reviewed-by: Ian Forbes <ian.forbes@broadcom.com>
Reviewed-by: Martin Krastev <martin.krastev@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240412025511.78553-5-zack.rusin@broadcom.com

parent b32233ac

drivers/gpu/drm/vmwgfx/vmwgfx_kms.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -933,6 +933,7 @@ int vmw_du_cursor_plane_atomic_check(struct drm_plane *plane,
		int vmw_du_crtc_atomic_check(struct drm_crtc *crtc,
		struct drm_atomic_state *state)
		{
		struct vmw_private *vmw = vmw_priv(crtc->dev);
		struct drm_crtc_state *new_state = drm_atomic_get_new_crtc_state(state,
		crtc);
		struct vmw_display_unit *du = vmw_crtc_to_du(new_state->crtc);
		@@ -940,9 +941,13 @@ int vmw_du_crtc_atomic_check(struct drm_crtc *crtc,
		bool has_primary = new_state->plane_mask &
		drm_plane_mask(crtc->primary);

		/* We always want to have an active plane with an active CRTC */
		if (has_primary != new_state->enable)
		return -EINVAL;
		/*
		* This is fine in general, but broken userspace might expect
		* some actual rendering so give a clue as why it's blank.
		*/
		if (new_state->enable && !has_primary)
		drm_dbg_driver(&vmw->drm,
		"CRTC without a primary plane will be blank.\n");


		if (new_state->connector_mask != connector_mask &&