drm/rockchip: Fix YUV buffers color rendering

Currently, YUV hardware overlays are converted to RGB using
a color space conversion different than BT.601.

The result is that colors of e.g. NV12 buffers don't match
colors of YUV hardware overlays.

In order to fix this, enable YUV2YUV and set appropriate coefficients
for formats such as NV12 to be displayed correctly.

This commit was tested using modetest, gstreamer and chromeos (hardware
accelerated video playback). Before the commit, tests rendering
with NV12 format resulted in colors not displayed correctly.

Test examples (Tested on RK3399 and RK3288 boards
connected to HDMI monitor):

  $ modetest 39@32:1920x1080@NV12
  $ gst-launch-1.0 videotestrc ! video/x-raw,format=NV12 ! kmssink

Signed-off-by: Daniele Castagna <dcastagna@chromium.org>
[ezequiel: rebase on linux-next and massage commit log]
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108214659.28794-1-ezequiel@collabora.com

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
index 0fe40e1983d9..aed467cd81b9 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
@@ -23,6 +23,8 @@
 #define VOP_MAJOR(version)		((version) >> 8)
 #define VOP_MINOR(version)		((version) & 0xff)
 
+#define NUM_YUV2YUV_COEFFICIENTS 12
+
 enum vop_data_format {
 	VOP_FMT_ARGB8888 = 0,
 	VOP_FMT_RGB888,
@@ -124,6 +126,10 @@ struct vop_scl_regs {
 	struct vop_reg scale_cbcr_y;
 };
 
+struct vop_yuv2yuv_phy {
+	struct vop_reg y2r_coefficients[NUM_YUV2YUV_COEFFICIENTS];
+};
+
 struct vop_win_phy {
 	const struct vop_scl_regs *scl;
 	const uint32_t *data_formats;
@@ -146,6 +152,12 @@ struct vop_win_phy {
 	struct vop_reg channel;
 };
 
+struct vop_win_yuv2yuv_data {
+	uint32_t base;
+	const struct vop_yuv2yuv_phy *phy;
+	struct vop_reg y2r_en;
+};
+
 struct vop_win_data {
 	uint32_t base;
 	const struct vop_win_phy *phy;
@@ -159,6 +171,7 @@ struct vop_data {
 	const struct vop_misc *misc;
 	const struct vop_modeset *modeset;
 	const struct vop_output *output;
+	const struct vop_win_yuv2yuv_data *win_yuv2yuv;
 	const struct vop_win_data *win;
 	unsigned int win_size;