No video with HDMI DIP

[Kieran-Weaver]

Hi, I am unable to get video with the HDMI DIP. The plymouth boot screen shows up, but then when the machine finishes booting up, the plymouth screen disappears and the monitor goes to sleep with No Signal. At that point, I can access the CHIP over SSH.

If I disable plymouth, there is no video whatsoever, the console never shows up either from u-boot or the kernel.

The monitor is detected over I2C, and the Chrontel CH7033 Video Encoder is detected by the kernel.

Booted device tree: dtc -I fs -O dts /sys/firmware/devicetree/base, https://pastebin.com/tHvgg3S1 Kernel message buffer: dmesg, https://pastebin.com/iuB5k1Xb I2C bus 1 map:

sudo i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- 37 -- -- 3a -- -- -- -- -- 
40: -- -- -- -- -- -- -- -- -- -- 4a 4b -- -- -- -- 
50: 50 -- -- -- 54 -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- UU --

EDID Info from the monitor, captured from the CHIP: get-edid | parse-edid, https://pastebin.com/93QEB2Ei

I'm running a stock bookworm armmp kernel, compiled using your instructions.

My monitor is a DIY monitor I made with a chromebook screen attached using a eDP to HDMI adapter, I tested it with a laptop and it works fine.

[macromorgan]

I... honestly don't know. To be brutally honest I don't have that device to test with, I just took some guesses. I have a similar device (a Source Parts Stovetop prototype board) that I did my testing with. I can see based on your i2c dump that it's seeing the device at 0x76 which is where it should be on the i2c bus. Does dmesg give you anything useful? What about the output from modetest?

[Kieran-Weaver]

Thank you so much! Modetest was what I needed. I got it to work by adding video=HDMI-A-1:1280x720@60e to my command line params.

modetest output:

trying to open device 'sun4i-drm'...done
Encoders:
id	crtc	type	possible crtcs	possible clones	
48	0	none	0x00000001	0x00000001
50	47	TVDAC	0x00000001	0x00000002

Connectors:
id	encoder	status		name		size (mm)	modes	encoders
49	0	connected	HDMI-A-1       	340x190		6	48
  modes:
	index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot
  #0 1360x768 59.66 1360 1424 1536 1792 768 771 777 795 85000 flags: phsync, pvsync; type: driver
  #1 1280x720 60.00 1280 1390 1430 1650 720 725 730 750 74250 flags: phsync, pvsync; type: driver
  #2 1280x720 50.00 1280 1720 1760 1980 720 725 730 750 74250 flags: phsync, pvsync; type: driver
  #3 720x576 50.00 720 732 796 864 576 581 586 625 27000 flags: nhsync, nvsync; type: driver
  #4 720x480 60.00 720 736 798 858 480 489 495 525 27027 flags: nhsync, nvsync; type: driver
  #5 720x480 59.94 720 736 798 858 480 489 495 525 27000 flags: nhsync, nvsync; type: driver