[PATCH 2/4] drm/hibmc: Fix list of formats on the primary plane

[Thomas Zimmermann <tzimmermann@suse.de>]

Remove all formats from the primary plane that are unsupported for
various reasons.

* Formats with alpha channel: planes should not announce alpha channels
unless they support transparency. There's no transparency support in
the primary plane's implementation.

* Formats with BGR order. The common format is in RGB channel order.
There's no BGR support in the primary plane's implementation.

* RGB888: atomic_update programs the format from cpp[0] * 8 / 16. For
RGB888's cpp value of 3 this returns 1.5; rounded to 1. Programming
the value of 1 to HIBMC_CRT_DISP_CTL_FORMAT sets up RGB565. Hence, the
output is distorted. This can be tested by booting with video=1024x768-24.

Removing all unsupported formats leaves XRGB8888 and RGB565. Both of
which are supported and work correctly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: da52605eea8f ("drm/hisilicon/hibmc: Add support for display engine")
Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Xinliang Liu <xinliang.liu@linaro.org>
Cc: Dmitry Baryshkov <lumag@kernel.org>
Cc: Yongbang Shi <shiyongbang@huawei.com>
Cc: Baihan Li <libaihan@huawei.com>
Cc: <stable@vger.kernel.org> # v4.10+
---
 drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_de.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_de.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_de.c
index 8fa2a95bcdd1..c4f9ebd9250d 100644
--- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_de.c
+++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_de.c
@@ -118,10 +118,8 @@ static void hibmc_plane_atomic_update(struct drm_plane *plane,
 }
 
 static const u32 channel_formats1[] = {
-	DRM_FORMAT_RGB565, DRM_FORMAT_BGR565, DRM_FORMAT_RGB888,
-	DRM_FORMAT_BGR888, DRM_FORMAT_XRGB8888, DRM_FORMAT_XBGR8888,
-	DRM_FORMAT_RGBA8888, DRM_FORMAT_BGRA8888, DRM_FORMAT_ARGB8888,
-	DRM_FORMAT_ABGR8888
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_RGB565,
 };
 
 static const struct drm_plane_funcs hibmc_plane_funcs = {
-- 
2.53.0