Re: [PATCH v4 04/11] drm/bridge: synopsys: dw-hdmi: add bus format negociation

On 02/03/2020 11:18, Laurent Pinchart wrote:

Hi Neil,

Thank you for the patch.

On Thu, Feb 06, 2020 at 08:18:27PM +0100, Neil Armstrong wrote:

...

Add the atomic_get_output_bus_fmts, atomic_get_input_bus_fmts to negociate the possible output and input formats for the current mode and monitor, and use the negotiated formats in a basic atomic_check callback.

Signed-off-by: Neil Armstrong narmstrong@baylibre.com

drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 272 +++++++++++++++++++++- 1 file changed, 268 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index fec4a4bcd1fe..15048ad694bc 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -2095,11 +2095,10 @@ 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) hdmi->hdmi_data.enc_in_bus_format = hdmi->plat_data->input_bus_format;
• else

• else if (hdmi->hdmi_data.enc_in_bus_format == MEDIA_BUS_FMT_FIXED) hdmi->hdmi_data.enc_in_bus_format = MEDIA_BUS_FMT_RGB888_1X24;

  /* TOFIX: Get input encoding from plat data or fallback to none */

@@ -2109,8 +2108,8 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode) 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 (hdmi->hdmi_data.enc_out_bus_format == MEDIA_BUS_FMT_FIXED)

• hdmi->hdmi_data.enc_out_bus_format = MEDIA_BUS_FMT_RGB888_1X24;
  
  

  hdmi->hdmi_data.pix_repet_factor = 0; hdmi->hdmi_data.hdcp_enable = 0;

@@ -2388,6 +2387,267 @@ static const struct drm_connector_helper_funcs dw_hdmi_connector_helper_funcs = .atomic_check = dw_hdmi_connector_atomic_check, };

+/*

• • Possible output formats :
• • • MEDIA_BUS_FMT_UYYVYY16_0_5X48,
• • • MEDIA_BUS_FMT_UYYVYY12_0_5X36,
• • • MEDIA_BUS_FMT_UYYVYY10_0_5X30,
• • • MEDIA_BUS_FMT_UYYVYY8_0_5X24,
• • • MEDIA_BUS_FMT_YUV16_1X48,
• • • MEDIA_BUS_FMT_RGB161616_1X48,
• • • MEDIA_BUS_FMT_UYVY12_1X24,
• • • MEDIA_BUS_FMT_YUV12_1X36,
• • • MEDIA_BUS_FMT_RGB121212_1X36,
• • • MEDIA_BUS_FMT_UYVY10_1X20,
• • • MEDIA_BUS_FMT_YUV10_1X30,
• • • MEDIA_BUS_FMT_RGB101010_1X30,
• • • MEDIA_BUS_FMT_UYVY8_1X16,
• • • MEDIA_BUS_FMT_YUV8_1X24,
• • • MEDIA_BUS_FMT_RGB888_1X24,
• */

I'd drop this comment as I don't think it brings much, except for a risk of getting out of sync with the implementation below :-)

I know it's redundant, but I'll prefer having it here to clarify which bus formats are handled.

...

+/* Can return a maximum of 12 possible output formats for a mode/connector */ +#define MAX_OUTPUT_SEL_FORMATS 12

I count 11 below.

Exact !

...

+static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,

• 			struct drm_bridge_state *bridge_state,
  

• 			struct drm_crtc_state *crtc_state,
  

• 			struct drm_connector_state *conn_state,
  

• 			unsigned int *num_output_fmts)
  

+{

• struct drm_connector *conn = conn_state->connector;
• struct drm_display_info *info = &conn->display_info;
• struct drm_display_mode *mode = &crtc_state->mode;
• u8 max_bpc = conn_state->max_requested_bpc;
• bool is_hdmi2_sink = info->hdmi.scdc.supported ||

• 	     (info->color_formats & DRM_COLOR_FORMAT_YCRCB420);
  

• u32 *output_fmts;
• int i = 0;

i is never negative, you can make it an unsigned int.

ok

...

• *num_output_fmts = 0;
• output_fmts = kcalloc(MAX_OUTPUT_SEL_FORMATS, sizeof(*output_fmts),

• 	      GFP_KERNEL);
  

• if (!output_fmts)

• return NULL;
  

• /*

• * If the current mode enforces 4:2:0, force the output but format
  

• * to 4:2:0 and do not add the YUV422/444/RGB formats
  

• */
  

• if (conn->ycbcr_420_allowed &&

•    (drm_mode_is_420_only(info, mode) ||
  

•     (is_hdmi2_sink && drm_mode_is_420_also(info, mode)))) {
  

• /* Order bus formats from 16bit to 8bit if supported */
  

• if (max_bpc >= 16 && info->bpc == 16 &&
  

•     (info->hdmi.y420_dc_modes & DRM_EDID_YCBCR420_DC_48))
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_UYYVYY16_0_5X48;
  

• if (max_bpc >= 12 && info->bpc >= 12 &&
  

•     (info->hdmi.y420_dc_modes & DRM_EDID_YCBCR420_DC_36))
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_UYYVYY12_0_5X36;
  

• if (max_bpc >= 10 && info->bpc >= 10 &&
  

•     (info->hdmi.y420_dc_modes & DRM_EDID_YCBCR420_DC_30))
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_UYYVYY10_0_5X30;
  

• /* Default 8bit fallback */
  

• output_fmts[i++] = MEDIA_BUS_FMT_UYYVYY8_0_5X24;
  

• *num_output_fmts = i;
  

• return output_fmts;
  

• }
• /*

• * Order bus formats from 16bit to 8bit and from YUV422 to RGB
  

• * if supported. In any case the default RGB888 format is added
  

• */
  

• if (max_bpc >= 16 && info->bpc == 16) {

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
  

• output_fmts[i++] = MEDIA_BUS_FMT_RGB161616_1X48;
  

• }
• if (max_bpc >= 12 && info->bpc >= 12) {

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;
  

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
  

• output_fmts[i++] = MEDIA_BUS_FMT_RGB121212_1X36;
  

• }
• if (max_bpc >= 10 && info->bpc >= 10) {

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
  

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
  

• 	output_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
  

• output_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
  

• }
• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)

• output_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
  

• if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)

• output_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
  

• /* Default 8bit RGB fallback */
• output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
• *num_output_fmts = i;
• return output_fmts;

+}

+/*

• • Possible input formats :
• • • MEDIA_BUS_FMT_RGB888_1X24
• • • MEDIA_BUS_FMT_YUV8_1X24
• • • MEDIA_BUS_FMT_UYVY8_1X16
• • • MEDIA_BUS_FMT_UYYVYY8_0_5X24
• • • MEDIA_BUS_FMT_RGB101010_1X30
• • • MEDIA_BUS_FMT_YUV10_1X30
• • • MEDIA_BUS_FMT_UYVY10_1X20
• • • MEDIA_BUS_FMT_UYYVYY10_0_5X30
• • • MEDIA_BUS_FMT_RGB121212_1X36
• • • MEDIA_BUS_FMT_YUV12_1X36
• • • MEDIA_BUS_FMT_UYVY12_1X24
• • • MEDIA_BUS_FMT_UYYVYY12_0_5X36
• • • MEDIA_BUS_FMT_RGB161616_1X48
• • • MEDIA_BUS_FMT_YUV16_1X48
• • • MEDIA_BUS_FMT_UYYVYY16_0_5X48
• */

Same here.

I'll prefer keeping these aswell

...

+/* Can return a maximum of 4 possible input formats for an output format */ +#define MAX_INPUT_SEL_FORMATS 4

As Boris pointed out, that should be 3.

Yep

...

+static u32 *dw_hdmi_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,

• 			struct drm_bridge_state *bridge_state,
  

• 			struct drm_crtc_state *crtc_state,
  

• 			struct drm_connector_state *conn_state,
  

• 			u32 output_fmt,
  

• 			unsigned int *num_input_fmts)
  

+{

• u32 *input_fmts;
• int i = 0;

i is never negative, you can make it an unsigned int.

ok

...

• *num_input_fmts = 0;
• input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),

• 	     GFP_KERNEL);
  

• if (!input_fmts)

• return NULL;
  

• switch (output_fmt) {
• /* 8bit */
• case MEDIA_BUS_FMT_RGB888_1X24:

• input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
  

• break;
  

• case MEDIA_BUS_FMT_YUV8_1X24:

• input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
  

• break;
  

• case MEDIA_BUS_FMT_UYVY8_1X16:

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
  

• break;
  

• /* 10bit */
• case MEDIA_BUS_FMT_RGB101010_1X30:

• input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
  

• break;
  

• case MEDIA_BUS_FMT_YUV10_1X30:

• input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
  

• break;
  

• case MEDIA_BUS_FMT_UYVY10_1X20:

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
  

• break;
  

• /* 12bit */
• case MEDIA_BUS_FMT_RGB121212_1X36:

• input_fmts[i++] = MEDIA_BUS_FMT_RGB121212_1X36;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;
  

• break;
  

• case MEDIA_BUS_FMT_YUV12_1X36:

• input_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
  

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB121212_1X36;
  

• break;
  

• case MEDIA_BUS_FMT_UYVY12_1X24:

• input_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB121212_1X36;
  

• break;
  

• /* 16bit */
• case MEDIA_BUS_FMT_RGB161616_1X48:

• input_fmts[i++] = MEDIA_BUS_FMT_RGB161616_1X48;
  

• input_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
  

• break;
  

• case MEDIA_BUS_FMT_YUV16_1X48:

• input_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
  

• input_fmts[i++] = MEDIA_BUS_FMT_RGB161616_1X48;
  

• break;
  

• /* 420 */

s/420/YUV 4:2:0/ ?

Looks better

...

• 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:

• input_fmts[i++] = output_fmt;
  

• break;
  

• }
• *num_input_fmts = i;
• if (*num_input_fmts == 0) {

• kfree(input_fmts);
  

• input_fmts = NULL;
  

• }
• return input_fmts;

+}

+static int dw_hdmi_bridge_atomic_check(struct drm_bridge *bridge,

• 		       struct drm_bridge_state *bridge_state,
  

• 		       struct drm_crtc_state *crtc_state,
  

• 		       struct drm_connector_state *conn_state)
  

+{

• struct dw_hdmi *hdmi = bridge->driver_private;
• dev_dbg(hdmi->dev, "selected output format %x\n",

s/%x/0x%04x/

...

• 	bridge_state->output_bus_cfg.format);
  

Misalignment ?

Fixed

...

• hdmi->hdmi_data.enc_out_bus_format =

• 	bridge_state->output_bus_cfg.format;
  

• dev_dbg(hdmi->dev, "selected input format %x\n",

• 	bridge_state->input_bus_cfg.format);
  

Same here. I would combine both messages:

dev_dbg(hdmi->dev, "input format: 0x%04x, output format: 0x04x\n", bridge_state->input_bus_cfg.format, bridge_state->output_bus_cfg.format);

Looks better

...

• hdmi->hdmi_data.enc_in_bus_format =

• 	bridge_state->input_bus_cfg.format;
  

• return 0;

+}

static int dw_hdmi_bridge_attach(struct drm_bridge *bridge) { struct dw_hdmi *hdmi = bridge->driver_private; @@ -2499,6 +2759,9 @@ static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = { .atomic_reset = drm_atomic_helper_bridge_reset, .attach = dw_hdmi_bridge_attach, .detach = dw_hdmi_bridge_detach,

• .atomic_check = dw_hdmi_bridge_atomic_check,
• .atomic_get_output_bus_fmts = dw_hdmi_bridge_atomic_get_output_bus_fmts,
• .atomic_get_input_bus_fmts = dw_hdmi_bridge_atomic_get_input_bus_fmts, .enable = dw_hdmi_bridge_enable, .disable = dw_hdmi_bridge_disable, .mode_set = dw_hdmi_bridge_mode_set,

@@ -2963,6 +3226,7 @@ __dw_hdmi_probe(struct platform_device *pdev,

hdmi->bridge.driver_private = hdmi; hdmi->bridge.funcs = &dw_hdmi_bridge_funcs;

This seems unrelated.

Yep

...

#ifdef CONFIG_OF hdmi->bridge.of_node = pdev->dev.of_node; #endif

Thanks, Neil