drm: shmobile: Add support for DRM_FORMAT_XRGB8888

DRM_FORMAT_XRGB8888 aka XR24 is the modus francus of DRM, and should be
supported by all drivers.

The handling for DRM_FORMAT_XRGB8888 is similar to DRM_FORMAT_ARGB8888,
just ignore the alpha channel.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/888cde6d1f70f1610931c4a89801060bb6765ff2.1684854992.git.geert+renesas@glider.be

drivers/gpu/drm/shmobile/shmob_drm_crtc.c

@@ -232,6 +232,7 @@ static void shmob_drm_crtc_start(struct shmob_drm_crtc *scrtc)
 		value = LDDDSR_LS | LDDDSR_WS | LDDDSR_BS;
 		break;
 	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
 	default:
 		value = LDDDSR_LS;
 		break;

drivers/gpu/drm/shmobile/shmob_drm_kms.c

@@ -39,6 +39,11 @@ static const struct shmob_drm_format_info shmob_drm_format_infos[] = {
 		.bpp = 32,
 		.yuv = false,
 		.lddfr = LDDFR_PKF_ARGB32,
+	}, {
+		.fourcc = DRM_FORMAT_XRGB8888,
+		.bpp = 32,
+		.yuv = false,
+		.lddfr = LDDFR_PKF_ARGB32,
 	}, {
 		.fourcc = DRM_FORMAT_NV12,
 		.bpp = 12,

drivers/gpu/drm/shmobile/shmob_drm_plane.c

@@ -80,6 +80,7 @@ static void __shmob_drm_plane_setup(struct shmob_drm_plane *splane,
 		format |= LDBBSIFR_SWPL | LDBBSIFR_SWPW | LDBBSIFR_SWPB;
 		break;
 	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
 	default:
 		format |= LDBBSIFR_SWPL;
 		break;
@@ -95,6 +96,9 @@ static void __shmob_drm_plane_setup(struct shmob_drm_plane *splane,
 	case DRM_FORMAT_ARGB8888:
 		format |= LDBBSIFR_AL_PK | LDBBSIFR_RY | LDDFR_PKF_ARGB32;
 		break;
+	case DRM_FORMAT_XRGB8888:
+		format |= LDBBSIFR_AL_1 | LDBBSIFR_RY | LDDFR_PKF_ARGB32;
+		break;
 	case DRM_FORMAT_NV12:
 	case DRM_FORMAT_NV21:
 		format |= LDBBSIFR_AL_1 | LDBBSIFR_CHRR_420;
@@ -231,6 +235,7 @@ static const uint32_t formats[] = {
 	DRM_FORMAT_RGB565,
 	DRM_FORMAT_RGB888,
 	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
 	DRM_FORMAT_NV12,
 	DRM_FORMAT_NV21,
 	DRM_FORMAT_NV16,