drivers/nouveau/kms/nv50-: Reject format modifiers for cursor planes

Nvidia hardware doesn't actually support using tiling formats with the
cursor plane, only linear is allowed. In the future, we should write a
testcase for this.

Fixes: c586f30b ("drm/nouveau/kms: Add format mod prop to base/ovly/nvdisp")
Cc: James Jones <jajones@nvidia.com>
Cc: Martin Peres <martin.peres@free.fr>
Cc: Jeremy Cline <jcline@redhat.com>
Cc: Simon Ser <contact@emersion.fr>
Cc: <stable@vger.kernel.org> # v5.8+
Signed-off-by: NLyude Paul <lyude@redhat.com>
Reviewed-by: NSimon Ser <contact@emersion.fr>
Reviewed-by: NJames Jones <jajones@nvidia.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

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

@@ -702,6 +702,11 @@ nv50_wndw_init(struct nv50_wndw *wndw)
 	nvif_notify_get(&wndw->notify);
 }
 
+static const u64 nv50_cursor_format_modifiers[] = {
+	DRM_FORMAT_MOD_LINEAR,
+	DRM_FORMAT_MOD_INVALID,
+};
+
 int
 nv50_wndw_new_(const struct nv50_wndw_func *func, struct drm_device *dev,
 	       enum drm_plane_type type, const char *name, int index,
@@ -713,6 +718,7 @@ nv50_wndw_new_(const struct nv50_wndw_func *func, struct drm_device *dev,
 	struct nvif_mmu *mmu = &drm->client.mmu;
 	struct nv50_disp *disp = nv50_disp(dev);
 	struct nv50_wndw *wndw;
+	const u64 *format_modifiers;
 	int nformat;
 	int ret;
 
@@ -728,10 +734,13 @@ nv50_wndw_new_(const struct nv50_wndw_func *func, struct drm_device *dev,
 
 	for (nformat = 0; format[nformat]; nformat++);
 
-	ret = drm_universal_plane_init(dev, &wndw->plane, heads, &nv50_wndw,
-				       format, nformat,
-				       nouveau_display(dev)->format_modifiers,
-				       type, "%s-%d", name, index);
+	if (type == DRM_PLANE_TYPE_CURSOR)
+		format_modifiers = nv50_cursor_format_modifiers;
+	else
+		format_modifiers = nouveau_display(dev)->format_modifiers;
+
+	ret = drm_universal_plane_init(dev, &wndw->plane, heads, &nv50_wndw, format, nformat,
+				       format_modifiers, type, "%s-%d", name, index);
 	if (ret) {
 		kfree(*pwndw);
 		*pwndw = NULL;