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Message-ID: <bff69815-1185-c74f-82ab-5b8f7faccfac@gmail.com>
Date:   Thu, 23 Nov 2023 13:54:28 +0100
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Subject: Re: [PATCH v1 3/4] drm/rockchip: rk3066_hdmi: Remove useless output
 format
To:     Heiko Stuebner <heiko@sntech.de>, hjc@rock-chips.com
Cc:     airlied@gmail.com, daniel@ffwll.ch,
        dri-devel@lists.freedesktop.org,
        linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
References: <cda574be-4f33-b66d-eb14-92c2b31d241e@gmail.com>
 <bb5cac77-a705-738e-13ae-667ea87f1cb1@gmail.com> <4308014.ejJDZkT8p0@phil>
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From:   Johan Jonker <jbx6244@gmail.com>
In-Reply-To: <4308014.ejJDZkT8p0@phil>
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On 11/20/23 18:06, Heiko Stuebner wrote:
> Hi Johan,
> 
> Am Donnerstag, 2. November 2023, 14:42:19 CET schrieb Johan Jonker:
>> The Rk3066 hdmi output format is hard coded to RGB. Remove
>> all useless code related to colorimetry and enc_out_format.
>>
>> Signed-off-by: Johan Jonker <jbx6244@gmail.com>
> 

> I guess my first question is, is the hardcoding happening just because
> of missing functionality in the driver, or does the hardware only
> support RGB?

This driver can do so much more..., but is crippled by various causes.
If in need for a full functional rk3066 driver a little bit help/advise/action from other people is needed.

1:
Missing rk3066 TRM HDMI register info.
Could Rockchip (= Sandy Huang) disclose this info to the open source community?

As a way around we can look at older driver code and port to mainline.
More info gives better results.
rk30_hdmi_config_csc() function:
https://github.com/RockchipOpensourceCommunity/px2-android-kernel-3.0/blob/master/drivers/video/rockchip/hdmi/chips/rkpx2/rkpx2_hdmi_hw.c#L315

2:
Could DRM people show us examples for:
- How to advertise to the VOP driver what data formats (RGB, YCBCR) it can send to the HDMI driver or any other Rockchip DRM sub driver other then RGB.
- Advertise EDID data monitor modes RGB444, YCBCR444 and YCBCR422 to the HDMI driver.

https://github.com/RockchipOpensourceCommunity/px2-android-kernel-3.0/blob/master/drivers/video/rockchip/hdmi/rk_hdmi_edid.c#L217C1-L218C41

3:
Advise when what Infoframe is needed for only RGB vs. the rest according to the specification.
https://engineering.purdue.edu/ece477/Archive/2012/Spring/S12-Grp10/Datasheets/CEC_HDMI_Specification.pdf

rk3066 currently only sends avi info. Does it need vsi as well? Can anyone give some clarity here?
inno_hdime sends avi and vsi info.

4:
rk3066_hdmi and inno_hdmi are HDMI 1.4a drivers for DVI and HDMI.
Validated by drm_match_cea_mode() this function only gives us both HDMI + HDMI2 focus, but nothing for old DVI monitors.
How to improve?

5:
Sound support was submitted:
Re: [PATCH v6 2/5] drm: rockchip: add sound support to rk3066 hdmi driver
https://lore.kernel.org/linux-rockchip/48dbe9b7-0aa0-f459-301f-f380e2b7f2f8@gmail.com/

No reply was given (by Heiko or others) on why it wasn't applied or what needs to be improved.

Without reply no improvement.

Johan


> 
> 
>> ---
>>  drivers/gpu/drm/rockchip/rk3066_hdmi.c | 20 +-------------------
>>  1 file changed, 1 insertion(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/rockchip/rk3066_hdmi.c b/drivers/gpu/drm/rockchip/rk3066_hdmi.c
>> index 0e7aae341960..f2b1b2faa096 100644
>> --- a/drivers/gpu/drm/rockchip/rk3066_hdmi.c
>> +++ b/drivers/gpu/drm/rockchip/rk3066_hdmi.c
>> @@ -23,8 +23,6 @@
>>
>>  struct hdmi_data_info {
>>  	int vic; /* The CEA Video ID (VIC) of the current drm display mode. */
>> -	unsigned int enc_out_format;
>> -	unsigned int colorimetry;
>>  };
>>
>>  struct rk3066_hdmi_i2c {
>> @@ -200,14 +198,7 @@ static int rk3066_hdmi_config_avi(struct rk3066_hdmi *hdmi,
>>  	rc = drm_hdmi_avi_infoframe_from_display_mode(&frame.avi,
>>  						      &hdmi->connector, mode);
>>
>> -	if (hdmi->hdmi_data.enc_out_format == HDMI_COLORSPACE_YUV444)
>> -		frame.avi.colorspace = HDMI_COLORSPACE_YUV444;
>> -	else if (hdmi->hdmi_data.enc_out_format == HDMI_COLORSPACE_YUV422)
>> -		frame.avi.colorspace = HDMI_COLORSPACE_YUV422;
>> -	else
>> -		frame.avi.colorspace = HDMI_COLORSPACE_RGB;
>> -
>> -	frame.avi.colorimetry = hdmi->hdmi_data.colorimetry;
>> +	frame.avi.colorspace = HDMI_COLORSPACE_RGB;
>>  	frame.avi.scan_mode = HDMI_SCAN_MODE_NONE;
>>
>>  	return rk3066_hdmi_upload_frame(hdmi, rc, &frame,
>> @@ -329,15 +320,6 @@ static int rk3066_hdmi_setup(struct rk3066_hdmi *hdmi,
>>  	struct drm_display_info *display = &hdmi->connector.display_info;
>>
>>  	hdmi->hdmi_data.vic = drm_match_cea_mode(mode);
>> -	hdmi->hdmi_data.enc_out_format = HDMI_COLORSPACE_RGB;
>> -
>> -	if (hdmi->hdmi_data.vic == 6 || hdmi->hdmi_data.vic == 7 ||
>> -	    hdmi->hdmi_data.vic == 21 || hdmi->hdmi_data.vic == 22 ||
>> -	    hdmi->hdmi_data.vic == 2 || hdmi->hdmi_data.vic == 3 ||
>> -	    hdmi->hdmi_data.vic == 17 || hdmi->hdmi_data.vic == 18)
>> -		hdmi->hdmi_data.colorimetry = HDMI_COLORIMETRY_ITU_601;
>> -	else
>> -		hdmi->hdmi_data.colorimetry = HDMI_COLORIMETRY_ITU_709;
> 

> while I can understand the RGB output format, why does the colorimetry
> also get removed? This looks like it is dependent on the mode itself
> and not the output format?

From the old driver these conditions apply whether csc is needed.
https://github.com/RockchipOpensourceCommunity/px2-android-kernel-3.0/blob/master/drivers/video/rockchip/hdmi/chips/rkpx2/rkpx2_hdmi_hw.c#L320C1-L324C3

	if( ((vpara->input_color == VIDEO_INPUT_COLOR_RGB) && (vpara->output_color == VIDEO_OUTPUT_RGB444)) ||
		((vpara->input_color == VIDEO_INPUT_COLOR_YCBCR) && (vpara->output_color != VIDEO_OUTPUT_RGB444) ))
	{
		return;
	}

> 
> Thanks
> Heiko
> 
>