[PATCH 3/5] drm/bridge: dw-hdmi: Add support for dynamic output format setup

From: Neil Armstrong
Date: Mon May 20 2019 - 09:40:28 EST


In order to support the HDMI2.0 YUV420, YUV422 and the 10bit, 12bit and
16bits outpu use cases, add support for the recently introduced bridge
callback format_set().

This callback will setup the new input format and encoding from encoder,
then these information will be used instead of the default ones
in the dw_hdmi_setup() function.

To determine the output bus format, has been added :
- support for the connector display_info bus_formats, where a fixed
output bus format can be enforced by the encoder
- support for synami output bus format depending on the input format,
especially the YUV420 input bus format, enforcing YUV420 as output
with the correct bit depth

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 121 ++++++++++++++++++++--
1 file changed, 112 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index b50c49caf7ae..284ce59be8f8 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -103,6 +103,8 @@ struct hdmi_vmode {
};

struct hdmi_data_info {
+ unsigned int bridge_in_bus_format;
+ unsigned int bridge_in_encoding;
unsigned int enc_in_bus_format;
unsigned int enc_out_bus_format;
unsigned int enc_in_encoding;
@@ -1838,8 +1840,51 @@ static void hdmi_disable_overflow_interrupts(struct dw_hdmi *hdmi)
HDMI_IH_MUTE_FC_STAT2);
}

+/*
+ * The DW-HDMI CSC can only interpolate and decimate from 4:2:2 to 4:4:4/RGB
+ * and from 4:4:4/RGB to 4:2:2.
+ * Default to RGB output except if 4:2:0 as input, which CSC cannot convert.
+ */
+static unsigned long dw_hdmi_determine_output_bus_format(struct dw_hdmi *hdmi)
+{
+ unsigned int depth = hdmi_bus_fmt_color_depth(
+ hdmi->hdmi_data.enc_in_bus_format);
+ bool is_420 = hdmi_bus_fmt_is_yuv420(hdmi->hdmi_data.enc_in_bus_format);
+ unsigned long fmt = MEDIA_BUS_FMT_RGB888_1X24;
+
+ switch (depth) {
+ case 8:
+ if (is_420)
+ fmt = MEDIA_BUS_FMT_UYYVYY8_0_5X24;
+ else
+ fmt = MEDIA_BUS_FMT_RGB888_1X24;
+ break;
+ case 10:
+ if (is_420)
+ fmt = MEDIA_BUS_FMT_UYYVYY10_0_5X30;
+ else
+ fmt = MEDIA_BUS_FMT_RGB101010_1X30;
+ break;
+ case 12:
+ if (is_420)
+ fmt = MEDIA_BUS_FMT_UYYVYY12_0_5X36;
+ else
+ fmt = MEDIA_BUS_FMT_RGB121212_1X36;
+ break;
+ case 16:
+ if (is_420)
+ fmt = MEDIA_BUS_FMT_UYYVYY16_0_5X48;
+ else
+ fmt = MEDIA_BUS_FMT_RGB161616_1X48;
+ break;
+ }
+
+ return fmt;
+}
+
static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
{
+ struct drm_display_info *display = &hdmi->connector.display_info;
int ret;

hdmi_disable_overflow_interrupts(hdmi);
@@ -1853,9 +1898,9 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
}

if ((hdmi->vic == 6) || (hdmi->vic == 7) ||
- (hdmi->vic == 21) || (hdmi->vic == 22) ||
- (hdmi->vic == 2) || (hdmi->vic == 3) ||
- (hdmi->vic == 17) || (hdmi->vic == 18))
+ (hdmi->vic == 21) || (hdmi->vic == 22) ||
+ (hdmi->vic == 2) || (hdmi->vic == 3) ||
+ (hdmi->vic == 17) || (hdmi->vic == 18))
hdmi->hdmi_data.enc_out_encoding = V4L2_YCBCR_ENC_601;
else
hdmi->hdmi_data.enc_out_encoding = V4L2_YCBCR_ENC_709;
@@ -1863,22 +1908,29 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
hdmi->hdmi_data.video_mode.mpixelrepetitionoutput = 0;
hdmi->hdmi_data.video_mode.mpixelrepetitioninput = 0;

- /* TOFIX: Get input format from plat data or fallback to RGB888 */
- if (hdmi->plat_data->input_bus_format)
+ if (hdmi->hdmi_data.bridge_in_bus_format)
+ hdmi->hdmi_data.enc_in_bus_format =
+ hdmi->hdmi_data.bridge_in_bus_format;
+ else if (hdmi->plat_data->input_bus_format)
hdmi->hdmi_data.enc_in_bus_format =
hdmi->plat_data->input_bus_format;
else
hdmi->hdmi_data.enc_in_bus_format = MEDIA_BUS_FMT_RGB888_1X24;

- /* TOFIX: Get input encoding from plat data or fallback to none */
- if (hdmi->plat_data->input_bus_encoding)
+ if (hdmi->hdmi_data.bridge_in_encoding)
+ hdmi->hdmi_data.enc_in_encoding =
+ hdmi->hdmi_data.bridge_in_encoding;
+ else if (hdmi->plat_data->input_bus_encoding)
hdmi->hdmi_data.enc_in_encoding =
hdmi->plat_data->input_bus_encoding;
else
hdmi->hdmi_data.enc_in_encoding = V4L2_YCBCR_ENC_DEFAULT;

- /* TOFIX: Default to RGB888 output format */
- hdmi->hdmi_data.enc_out_bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+ if (display->num_bus_formats)
+ hdmi->hdmi_data.enc_out_bus_format = display->bus_formats[0];
+ else
+ hdmi->hdmi_data.enc_out_bus_format =
+ dw_hdmi_determine_output_bus_format(hdmi);

hdmi->hdmi_data.pix_repet_factor = 0;
hdmi->hdmi_data.hdcp_enable = 0;
@@ -2150,6 +2202,56 @@ dw_hdmi_bridge_mode_valid(struct drm_bridge *bridge,
return mode_status;
}

+static bool dw_hdmi_drm_bridge_format_set(struct drm_bridge *bridge,
+ const u32 input_bus_format,
+ const u32 input_encoding)
+{
+ struct dw_hdmi *hdmi = bridge->driver_private;
+
+ /* Filter supported input bus formats */
+ switch (input_bus_format) {
+ case MEDIA_BUS_FMT_RGB888_1X24:
+ case MEDIA_BUS_FMT_RGB101010_1X30:
+ case MEDIA_BUS_FMT_RGB121212_1X36:
+ case MEDIA_BUS_FMT_RGB161616_1X48:
+ case MEDIA_BUS_FMT_YUV8_1X24:
+ case MEDIA_BUS_FMT_YUV10_1X30:
+ case MEDIA_BUS_FMT_YUV12_1X36:
+ case MEDIA_BUS_FMT_YUV16_1X48:
+ case MEDIA_BUS_FMT_UYVY8_1X16:
+ case MEDIA_BUS_FMT_UYVY10_1X20:
+ case MEDIA_BUS_FMT_UYVY12_1X24:
+ case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
+ case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
+ case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
+ case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
+ break;
+ default:
+ dev_dbg(hdmi->dev, "Unsupported Input bus format %x\n",
+ input_bus_format);
+ return false;
+ }
+
+ /* Filter supported input bus encoding */
+ switch (input_encoding) {
+ case V4L2_YCBCR_ENC_DEFAULT:
+ case V4L2_YCBCR_ENC_601:
+ case V4L2_YCBCR_ENC_709:
+ case V4L2_YCBCR_ENC_XV601:
+ case V4L2_YCBCR_ENC_XV709:
+ break;
+ default:
+ dev_dbg(hdmi->dev, "Unsupported Input encoding %x\n",
+ input_bus_format);
+ return false;
+ }
+
+ hdmi->hdmi_data.bridge_in_bus_format = input_bus_format;
+ hdmi->hdmi_data.bridge_in_encoding = input_encoding;
+
+ return true;
+}
+
static void dw_hdmi_bridge_mode_set(struct drm_bridge *bridge,
const struct drm_display_mode *orig_mode,
const struct drm_display_mode *mode)
@@ -2192,6 +2294,7 @@ static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = {
.disable = dw_hdmi_bridge_disable,
.mode_set = dw_hdmi_bridge_mode_set,
.mode_valid = dw_hdmi_bridge_mode_valid,
+ .format_set = dw_hdmi_drm_bridge_format_set,
};

static irqreturn_t dw_hdmi_i2c_irq(struct dw_hdmi *hdmi)
--
2.21.0