drm/nouveau/kms/nv04-nv4x: fix exposed format list

drm_crtc_init exposes the XRGB8888 and ARGB8888 formats. In actuality,
ARGB8888's 32-bit depth messes up some formulas that weren't meant for
it, and the alpha is fairly meaningless for the primary plane.

The modesetting logic appears to be fully prepared for RGB565 as well as
XRGB1555 however, as tested with modetest.
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

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

@@ -1096,6 +1096,38 @@ static const struct drm_crtc_helper_funcs nv04_crtc_helper_funcs = {
 	.disable = nv_crtc_disable,
 };
 
+static const uint32_t modeset_formats[] = {
+        DRM_FORMAT_XRGB8888,
+        DRM_FORMAT_RGB565,
+        DRM_FORMAT_XRGB1555,
+};
+
+static struct drm_plane *
+create_primary_plane(struct drm_device *dev)
+{
+        struct drm_plane *primary;
+        int ret;
+
+        primary = kzalloc(sizeof(*primary), GFP_KERNEL);
+        if (primary == NULL) {
+                DRM_DEBUG_KMS("Failed to allocate primary plane\n");
+                return NULL;
+        }
+
+        /* possible_crtc's will be filled in later by crtc_init */
+        ret = drm_universal_plane_init(dev, primary, 0,
+                                       &drm_primary_helper_funcs,
+                                       modeset_formats,
+                                       ARRAY_SIZE(modeset_formats), NULL,
+                                       DRM_PLANE_TYPE_PRIMARY, NULL);
+        if (ret) {
+                kfree(primary);
+                primary = NULL;
+        }
+
+        return primary;
+}
+
 int
 nv04_crtc_create(struct drm_device *dev, int crtc_num)
 {
@@ -1114,7 +1146,9 @@ nv04_crtc_create(struct drm_device *dev, int crtc_num)
 	nv_crtc->save = nv_crtc_save;
 	nv_crtc->restore = nv_crtc_restore;
 
-	drm_crtc_init(dev, &nv_crtc->base, &nv04_crtc_funcs);
+	drm_crtc_init_with_planes(dev, &nv_crtc->base,
+                                  create_primary_plane(dev), NULL,
+                                  &nv04_crtc_funcs, NULL);
 	drm_crtc_helper_add(&nv_crtc->base, &nv04_crtc_helper_funcs);
 	drm_mode_crtc_set_gamma_size(&nv_crtc->base, 256);