Hi,
On 14/01/2022 15:23, Biju Das wrote:
-----Original Message----- From: Neil Armstrong narmstrong@baylibre.com Sent: 14 January 2022 13:56 To: Biju Das biju.das.jz@bp.renesas.com; Fabio Estevam festevam@gmail.com Cc: daniel@ffwll.ch; Laurent.pinchart@ideasonboard.com; robert.foss@linaro.org; jonas@kwiboo.se; jernej.skrabec@gmail.com; martin.blumenstingl@googlemail.com; linux-amlogic@lists.infradead.org; linux-arm-kernel@lists.infradead.org; dri-devel@lists.freedesktop.org; linux-kernel@vger.kernel.org; linux-renesas-soc@vger.kernel.org Subject: Re: dw_hdmi is showing wrong colour after commit 7cd70656d1285b79("drm/bridge: display-connector: implement bus fmts callbacks")
Hi,
On 14/01/2022 12:08, Biju Das wrote:
Hi Neil,
Subject: Re: dw_hdmi is showing wrong colour after commit 7cd70656d1285b79("drm/bridge: display-connector: implement bus fmts callbacks")
On 14/01/2022 09:29, Biju Das wrote:
Hi Neil,
- renesas-soc
Subject: Re: dw_hdmi is showing wrong colour after commit 7cd70656d1285b79("drm/bridge: display-connector: implement bus fmts callbacks")
Hi,
On 13/01/2022 21:01, Fabio Estevam wrote: > Hi Biju, > > On Thu, Jan 13, 2022 at 2:45 PM Biju Das > biju.das.jz@bp.renesas.com wrote: >> >> Hi All, >> >> RZ/G2{H, M, N} SoC has dw_hdmi IP and it was working ok(colour) >> till the commit >> 7cd70656d1285b79("drm/bridge: display-connector: implement bus >> fmts callbacks"). >> >> After this patch, the screen becomes greenish(may be it is >> setting it into YUV format??). >> >> By checking the code, previously it used to call get_input_fmt >> callback and set colour as RGB24. >> >> After this commit, it calls get_output_fmt_callbck and returns 3 >> outputformats(YUV16, YUV24 and RGB24) And get_input_fmt callback, >> I see the outputformat as YUV16 instead of RGB24. >> >> Not sure, I am the only one seeing this issue with dw_HDMI driver.
This patch was introduced to maintain the bridge color format negotiation after using DRM_BRIDGE_ATTACH_NO_CONNECTOR, but it seems it behaves incorrectly if the first bridge doesn't implement the negotiation callbacks.
Let me check the code to see how to fix that.
Thanks for the information, I am happy to test the patch/fix.
Cheers, Biju
> > I have tested linux-next 20220112 on a imx6q-sabresd board, which
shows:
> > dwhdmi-imx 120000.hdmi: Detected HDMI TX controller v1.30a with > HDCP (DWC HDMI 3D TX PHY) > > The colors are shown correctly here. >
The imx doesn't use DRM_BRIDGE_ATTACH_NO_CONNECTOR so the negotiation fails and use the RGB fallback input & output format.
Anyway thanks for testing
Neil
Can you test :
==><=============================== diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index c96847fc0ebc..7019acd37716 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -955,7 +955,14 @@ drm_atomic_bridge_chain_select_bus_fmts(struct drm_bridge *bridge, last_bridge_state = drm_atomic_get_new_bridge_state(crtc_state-
state,
last_bridge);
if (last_bridge->funcs->atomic_get_output_bus_fmts) {
/** Only negociate with real values if both end of the bridgechain
* support negociation callbacks, otherwise you can end in asituation
* where the selected output format doesn't match with the- first
bridge
* output format.*/if (bridge->funcs->atomic_get_input_bus_fmts &&last_bridge->funcs->atomic_get_output_bus_fmts) { const struct drm_bridge_funcs *funcs =last_bridge->funcs;
/*@@ -980,7 +987,12 @@ drm_atomic_bridge_chain_select_bus_fmts(struct drm_bridge *bridge, if (!out_bus_fmts) return -ENOMEM;
if (conn->display_info.num_bus_formats &&
/** If first bridge doesn't support negociation, useMEDIA_BUS_FMT_FIXED
* as a safe value for the whole bridge chain*/if (bridge->funcs->atomic_get_input_bus_fmts &&conn->display_info.num_bus_formats && conn->display_info.bus_formats) out_bus_fmts[0] = conn-display_info.bus_formats[0];
else==><===============================
This should exclude your situation where the first bridge doesn't support negociation.
I have tested this fix with Linux next-20220114. Still I see colour
issue.
It is still negotiating and it is calling get_output_fmt_callbck
[ 3.460155] ########dw_hdmi_bridge_atomic_get_output_bus_fmts
MEDIA_BUS_FMT_UYVY8_1X16=0#########
[ 3.460180] ########dw_hdmi_bridge_atomic_get_output_bus_fmts
MEDIA_BUS_FMT_YUV8_1X24=1#########
[ 3.460202] ########dw_hdmi_bridge_atomic_get_output_bus_fmts
MEDIA_BUS_FMT_RGB888_1X24=2#########
And In get_input_fmt callback, I See the outputformat as YUV16 instead
of RGB24.
[ 3.460319] ########dw_hdmi_bridge_atomic_get_input_bus_fmts
MEDIA_BUS_FMT_UYVY8_1X16#########
[ 3.473644] ########hdmi_video_sample
MEDIA_BUS_FMT_UYVY8_1X16#########
OK, looking at rcar-du, the dw-hdmi bridge is directly connected to the encoder.
Yep.
Let me figure that out, no sure I can find a clean solution except putting back RGB24 before YUV.
Anyway please test that:
It works now after reordering.
[ 3.493302] ########dw_hdmi_bridge_atomic_get_output_bus_fmts MEDIA_BUS_FMT_RGB888_1X24=0######### [ 3.493326] ########dw_hdmi_bridge_atomic_get_output_bus_fmts MEDIA_BUS_FMT_YUV8_1X24=1######### [ 3.493348] ########dw_hdmi_bridge_atomic_get_output_bus_fmts MEDIA_BUS_FMT_UYVY8_1X16=2#########
[ 3.493463] ########dw_hdmi_bridge_atomic_get_input_bus_fmts MEDIA_BUS_FMT_RGB888_1X24######### [ 3.506797] ########hdmi_video_sample MEDIA_BUS_FMT_RGB888_1X24#########
Is it acceptable solution to the users of dw_hdmi driver? May be it is worth to post a patch. at least it is fixing the colour issue??
Yes, it gets back to default behavior before negociation, nevertheless we need to think how to handle your use-case correctly at some point.
I'll post this as a patch ASAP so it gets applied before landing in linus master.
Neil
Regards, Biju
==><=============================== diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index 54d8fdad395f..68f79094f648 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -2589,45 +2589,44 @@ static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge, }
/*
* Order bus formats from 16bit to 8bit and from YUV422 to RGB
* Order bus formats from 16bit to 8bit and from RGB to YUV422
- if supported. In any case the default RGB888 format is added
*/
if (max_bpc >= 16 && info->bpc == 16) {
output_fmts[i++] = MEDIA_BUS_FMT_RGB161616_1X48;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;
output_fmts[i++] = MEDIA_BUS_FMT_RGB121212_1X36;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 (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)output_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;}
if (max_bpc >= 10 && info->bpc >= 10) {
if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)output_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
output_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;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_UYVY10_1X20;
- if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)
output_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
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;
if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422)
output_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;*num_output_fmts = i;
==><===============================
Neil
Regards, Biju