drm/nouveau/kms/nv50: workaround EFI GOP window channel format differences

Should fix some initial modeset failures on (at least) Ampere boards.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drivers/gpu/drm/nouveau/dispnv50/disp.c

@@ -2237,6 +2237,33 @@ nv50_disp_atomic_commit_tail(struct drm_atomic_state *state)
 		interlock[NV50_DISP_INTERLOCK_CORE] = 0;
 	}
 
+	/* Finish updating head(s)...
+	 *
+	 * NVD is rather picky about both where window assignments can change,
+	 * *and* about certain core and window channel states matching.
+	 *
+	 * The EFI GOP driver on newer GPUs configures window channels with a
+	 * different output format to what we do, and the core channel update
+	 * in the assign_windows case above would result in a state mismatch.
+	 *
+	 * Delay some of the head update until after that point to workaround
+	 * the issue.  This only affects the initial modeset.
+	 *
+	 * TODO: handle this better when adding flexible window mapping
+	 */
+	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
+		struct nv50_head_atom *asyh = nv50_head_atom(new_crtc_state);
+		struct nv50_head *head = nv50_head(crtc);
+
+		NV_ATOMIC(drm, "%s: set %04x (clr %04x)\n", crtc->name,
+			  asyh->set.mask, asyh->clr.mask);
+
+		if (asyh->set.mask) {
+			nv50_head_flush_set_wndw(head, asyh);
+			interlock[NV50_DISP_INTERLOCK_CORE] = 1;
+		}
+	}
+
 	/* Update plane(s). */
 	for_each_new_plane_in_state(state, plane, new_plane_state, i) {
 		struct nv50_wndw_atom *asyw = nv50_wndw_atom(new_plane_state);

drivers/gpu/drm/nouveau/dispnv50/head.c

@@ -50,11 +50,8 @@ nv50_head_flush_clr(struct nv50_head *head,
 }
 
 void
-nv50_head_flush_set(struct nv50_head *head, struct nv50_head_atom *asyh)
+nv50_head_flush_set_wndw(struct nv50_head *head, struct nv50_head_atom *asyh)
 {
-	if (asyh->set.view   ) head->func->view    (head, asyh);
-	if (asyh->set.mode   ) head->func->mode    (head, asyh);
-	if (asyh->set.core   ) head->func->core_set(head, asyh);
 	if (asyh->set.olut   ) {
 		asyh->olut.offset = nv50_lut_load(&head->olut,
 						  asyh->olut.buffer,
@@ -62,6 +59,14 @@ nv50_head_flush_set(struct nv50_head *head, struct nv50_head_atom *asyh)
 						  asyh->olut.load);
 		head->func->olut_set(head, asyh);
 	}
+}
+
+void
+nv50_head_flush_set(struct nv50_head *head, struct nv50_head_atom *asyh)
+{
+	if (asyh->set.view   ) head->func->view    (head, asyh);
+	if (asyh->set.mode   ) head->func->mode    (head, asyh);
+	if (asyh->set.core   ) head->func->core_set(head, asyh);
 	if (asyh->set.curs   ) head->func->curs_set(head, asyh);
 	if (asyh->set.base   ) head->func->base    (head, asyh);
 	if (asyh->set.ovly   ) head->func->ovly    (head, asyh);

drivers/gpu/drm/nouveau/dispnv50/head.h

@@ -21,6 +21,7 @@ struct nv50_head {
 
 struct nv50_head *nv50_head_create(struct drm_device *, int index);
 void nv50_head_flush_set(struct nv50_head *head, struct nv50_head_atom *asyh);
+void nv50_head_flush_set_wndw(struct nv50_head *head, struct nv50_head_atom *asyh);
 void nv50_head_flush_clr(struct nv50_head *head,
 			 struct nv50_head_atom *asyh, bool flush);