[PATCH v4 09/11] drm/meson: venc: add support for YUV420 setup

From: Neil Armstrong
Date: Thu Feb 06 2020 - 14:18:59 EST


This patch adds encoding support for the YUV420 output from the
Amlogic Meson SoCs Video Processing Unit to the HDMI Controller.

The YUV420 is obtained by generating a YUV444 pixel stream like
the classic HDMI display modes, but then the Video Encoder output
can be configured to down-sample the YUV444 pixel stream to a YUV420
stream.

In addition if pixel stream down-sampling, the Y Cb Cr components must
also be mapped differently to align with the HDMI2.0 specifications.

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/gpu/drm/meson/meson_dw_hdmi.c | 3 ++-
drivers/gpu/drm/meson/meson_venc.c | 8 +++++---
drivers/gpu/drm/meson/meson_venc.h | 2 ++
3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
index 686c47106a18..f5d46d082534 100644
--- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
@@ -772,7 +772,8 @@ static void meson_venc_hdmi_encoder_mode_set(struct drm_bridge *bridge,
DRM_DEBUG_DRIVER("\"%s\" vic %d\n", mode->name, vic);

/* VENC + VENC-DVI Mode setup */
- meson_venc_hdmi_mode_set(priv, vic, mode);
+ meson_venc_hdmi_mode_set(priv, vic, ycrcb_map, false,
+ VPU_HDMI_OUTPUT_CBYCR);

/* VCLK Set clock */
dw_hdmi_set_vclk(dw_hdmi, mode);
diff --git a/drivers/gpu/drm/meson/meson_venc.c b/drivers/gpu/drm/meson/meson_venc.c
index a9ab78970bfe..f93c725b6f02 100644
--- a/drivers/gpu/drm/meson/meson_venc.c
+++ b/drivers/gpu/drm/meson/meson_venc.c
@@ -946,6 +946,8 @@ bool meson_venc_hdmi_venc_repeat(int vic)
EXPORT_SYMBOL_GPL(meson_venc_hdmi_venc_repeat);

void meson_venc_hdmi_mode_set(struct meson_drm *priv, int vic,
+ unsigned int ycrcb_map,
+ bool yuv420_mode,
const struct drm_display_mode *mode)
{
union meson_hdmi_venc_mode *vmode = NULL;
@@ -1528,14 +1530,14 @@ void meson_venc_hdmi_mode_set(struct meson_drm *priv, int vic,
if (mode->flags & DRM_MODE_FLAG_PVSYNC)
reg |= VPU_HDMI_INV_VSYNC;

- /* Output data format: CbYCr */
- reg |= VPU_HDMI_OUTPUT_CBYCR;
+ /* Output data format */
+ reg |= ycrcb_map;

/*
* Write rate to the async FIFO between VENC and HDMI.
* One write every 2 wr_clk.
*/
- if (venc_repeat)
+ if (venc_repeat || yuv420_mode)
reg |= VPU_HDMI_WR_RATE(2);

/*
diff --git a/drivers/gpu/drm/meson/meson_venc.h b/drivers/gpu/drm/meson/meson_venc.h
index 1abdcbdf51c0..9138255ffc9e 100644
--- a/drivers/gpu/drm/meson/meson_venc.h
+++ b/drivers/gpu/drm/meson/meson_venc.h
@@ -60,6 +60,8 @@ extern struct meson_cvbs_enci_mode meson_cvbs_enci_ntsc;
void meson_venci_cvbs_mode_set(struct meson_drm *priv,
struct meson_cvbs_enci_mode *mode);
void meson_venc_hdmi_mode_set(struct meson_drm *priv, int vic,
+ unsigned int ycrcb_map,
+ bool yuv420_mode,
const struct drm_display_mode *mode);
unsigned int meson_venci_get_field(struct meson_drm *priv);

--
2.22.0