From: Jonas Karlman <jonas@kwiboo.se>
To: "Jernej Škrabec" <jernej.skrabec@siol.net>,
a.hajda@samsung.com, Laurent.pinchart@ideasonboard.com,
boris.brezillon@collabora.com,
"Neil Armstrong" <narmstrong@baylibre.com>
Cc: linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org,
dri-devel@lists.freedesktop.org
Subject: Re: [PATCH v4 04/11] drm/bridge: synopsys: dw-hdmi: add bus format negociation
Date: Sat, 29 Feb 2020 10:09:14 +0000 (UTC) [thread overview]
Message-ID: <64b6ef10-b2e2-02f3-56dd-14dd0782a7aa@kwiboo.se> (raw)
In-Reply-To: <5330543.DvuYhMxLoT@jernej-laptop>
Hi Jernej,
On 2020-02-29 08:42, Jernej Škrabec wrote:
> Hi Neil!
>
> Dne četrtek, 06. februar 2020 ob 20:18:27 CET je Neil Armstrong napisal(a):
>> 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,
>> + */
>> +
>> +/* Can return a maximum of 12 possible output formats for a mode/connector
>> */ +#define MAX_OUTPUT_SEL_FORMATS 12
>> +
>> +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;
>> +
>> + *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) ||
>> + ())) {
>> +
>> + /* 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;
>
> Driver shouldn't return just yet for case "is_hdmi2_sink &&
> drm_mode_is_420_also(info, mode)", because monitor/TV also supports YCbCr
> 4:4:4 in that case. IMO YCbCr 4:4:4 should be even prefered. What do you
> think?
I think we need to have some way for controller driver and userspace to control what
hdmi output format gets selected. I know for a fact that some Samsung TV have issues
with 444 YCbCr modes at 4k 50/60hz but have no problems with 420 modes.
The Samsung TV edid lie and/or the TV is not fully following HDMI specs.
From a personal and mediaplayer userspace perspective I would like to prefer
420/444 YCbCr mode as soon as any yuv drm plane is active and rgb 444 anytime else.
On Rockchip SoCs the display controller cannot output yuv422 to dw-hdmi block,
the optimal output format selection in such case should put yuv422 last.
Maybe dw-hdmi can call a dw-hdmi glue driver callback to get the preferred output format order?
On a side note but related issue, the dw-hdmi format negotiation code should
probably also filter modes on tmds rate, something like [1].
It is needed to filter out deep color modes that is not supported by the sink or hdmi spec.
[1] https://github.com/Kwiboo/linux-rockchip/commit/fc3df6903384e764ab6ac59879c489cbef55fcbe
Best regards,
Jonas
>
> Best regards,
> Jernej
>
>> + }
>> +
>> + /*
>> + * 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
>> + */
>> +
>> +/* Can return a maximum of 4 possible input formats for an output format */
>> +#define MAX_INPUT_SEL_FORMATS 4
>> +
>> +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;
>> +
>> + *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 */
>> + 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",
>> + bridge_state->output_bus_cfg.format);
>> +
>> + 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);
>> +
>> + 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;
>> +
>> #ifdef CONFIG_OF
>> hdmi->bridge.of_node = pdev->dev.of_node;
>> #endif
>
>
>
>
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next prev parent reply other threads:[~2020-02-29 10:09 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-06 19:18 [PATCH v4 00/11] drm/bridge: dw-hdmi: implement bus-format negotiation and YUV420 support Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 01/11] drm/bridge: dw-hdmi: set mtmdsclock for deep color Neil Armstrong
2020-03-02 9:05 ` Laurent Pinchart
2020-03-02 9:21 ` Neil Armstrong
2020-03-02 15:54 ` Neil Armstrong
2020-03-02 16:01 ` Laurent Pinchart
2020-02-06 19:18 ` [PATCH v4 02/11] drm/bridge: dw-hdmi: add max bpc connector property Neil Armstrong
2020-02-17 6:38 ` Jernej Škrabec
2020-02-21 8:50 ` Neil Armstrong
2020-03-02 9:18 ` Laurent Pinchart
2020-03-02 15:55 ` Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 03/11] drm/bridge: dw-hdmi: Plug atomic state hooks to the default implementation Neil Armstrong
2020-02-07 10:57 ` Boris Brezillon
2020-03-02 9:56 ` Laurent Pinchart
2020-03-02 15:55 ` Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 04/11] drm/bridge: synopsys: dw-hdmi: add bus format negociation Neil Armstrong
2020-02-07 11:02 ` Boris Brezillon
2020-02-07 13:36 ` Neil Armstrong
2020-02-29 7:42 ` Jernej Škrabec
2020-02-29 10:09 ` Jonas Karlman [this message]
2020-02-29 11:07 ` Jernej Škrabec
2020-02-29 12:15 ` Jonas Karlman
2020-02-29 14:42 ` Jernej Škrabec
2020-03-02 8:08 ` Neil Armstrong
2020-03-02 8:04 ` Neil Armstrong
2020-03-02 10:18 ` Laurent Pinchart
2020-03-02 15:57 ` Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 05/11] drm/bridge: synopsys: dw-hdmi: allow ycbcr420 modes for >= 0x200a Neil Armstrong
2020-02-07 13:38 ` Neil Armstrong
2020-03-02 10:03 ` Laurent Pinchart
2020-03-02 15:58 ` Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 06/11] drm/meson: venc: make drm_display_mode const Neil Armstrong
2020-02-07 13:39 ` Neil Armstrong
2020-03-02 9:59 ` Laurent Pinchart
2020-02-06 19:18 ` [PATCH v4 07/11] drm/meson: meson_dw_hdmi: add bridge and switch to drm_bridge_funcs Neil Armstrong
2020-02-07 14:57 ` Boris Brezillon
2020-02-07 15:36 ` Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 08/11] drm/meson: dw-hdmi: stop enforcing input_bus_format Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 09/11] drm/meson: venc: add support for YUV420 setup Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 10/11] drm/meson: vclk: " Neil Armstrong
2020-02-06 19:18 ` [PATCH v4 11/11] drm/meson: Add YUV420 output support Neil Armstrong
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