Enabling DP0 in custom board as HDMI

touseef · October 1, 2019, 4:26pm

DP1 is being used as HDMI and its working fine. And we aren’t able to detect other connected device on DP0. Complete dmesg is attached
dmesg.txt (72.5 KB)

WayneWWW · October 2, 2019, 2:49am

Please check if DP0/DP1 are using the same pinmux setting.
Are you using pure nv driver? I saw there is “[ 0.416024] tegradc 15210000.nvdisplay: hdmi: No useable modes found for monitor, falling back to VGA”, but official driver seems not have this debug message.
Does hotplug work? Is tegra able to read display edid?
Have you checked the device tree?

touseef · October 2, 2019, 2:26pm

1: I am not sure how to check pinmux settings.

2: I flashed tx2 by using Jetpack, so I suppose it is pure nv driver.

3: Its hotplugged, but we aren’t able to read display edid memory. In the display properties of linux OS we can see all properties of hdmi display attached on DP1.

4:
/proc/device-tree/host1x/dpaux@15040000/status
okay

/proc/device-tree/host1x/dpaux@155c0000/status
disabled

/proc/device-tree/host1x/sor1/status
okay

/proc/device-tree/host1x/sor1/dp-display/status
disabled

/proc/device-tree/host1x/sor/status
disabled

/proc/device-tree/host1x/sor/dp-display/status
disabled

/proc/device-tree/host1x/nvdisplay@15200000/status
disabled

/proc/device-tree/host1x/nvdisplay@15210000/status
okay

/proc/device-tree/host1x/nvdisplay@15220000/status
disabled

WayneWWW · October 3, 2019, 9:14am

Hi,

If you are using dp-display in sor1 why are you disabling dp-display?

Actually, it is really hard to tell what is wrong with current information.

Please share

Your board schematics
Your current device tree
Your release revision of source code
.
I don’t see any “No useable modes found for monitor” keywords in our rel-32 driver source… not sure where it came from. Maybe I miss it. Could you help point out where is this line?

touseef · October 3, 2019, 2:21pm

Hi,
Thank you for replying, we haven’t disabled any port.

Current Device Tree:
/proc/device-tree/host1x/dpaux@15040000/status
okay

/proc/device-tree/host1x/dpaux@155c0000/status
disabled

/proc/device-tree/host1x/sor1/status
okay

/proc/device-tree/host1x/sor1/dp-display/status
disabled

/proc/device-tree/host1x/sor/status
disabled

/proc/device-tree/host1x/sor/dp-display/status
disabled

/proc/device-tree/host1x/nvdisplay@15200000/status
disabled

/proc/device-tree/host1x/nvdisplay@15210000/status
okay

/proc/device-tree/host1x/nvdisplay@15220000/status
disabled

And I am not sure which code you are asking for.
Schematics for HDMI is attached below

Tx2 hdmi schematic.pdf (903 KB)

WayneWWW · October 4, 2019, 2:19am

Sorry, I thought you are trying to enable dp.

Do you enable hdmi-display under sor1?

touseef · October 4, 2019, 8:37am

Hdmi was enabled by default

WayneWWW · October 4, 2019, 8:46am

What release is it? rel-32.2? rel-32.1?

touseef · October 6, 2019, 5:37am

Os version 16.04
Linux Kernel version 4.4.38-tegra
Jetpack: Tegra linux driver package version R28.2.1

WayneWWW · October 7, 2019, 2:35am

For the pinmux, please refer to tx2 adaptation guide. Your two pins of DP0/DP1 should match.
Could you check where does this line “[ 0.416024] tegradc 15210000.nvdisplay: hdmi: No useable modes found for monitor, falling back to VGA” come from?