R32.2 ttyS2 not work

Autonomous Machines Jetson & Embedded Systems Jetson TX1
1

With R32.2, I’d like to change the contole-terminal to ttyS2 and
followed the steps

1.  IN DTS, the new config is as the following
     serial@70006200 {
	compatible = "nvidia,tegra210-uart", "nvidia,tegra114-hsuart";
	status = "okay";
};


2. CMDLINE_ADD="console=ttyS2,115200n8 console=tty2 OS=l4t fbcon=map:0 net.ifnames=0";
   in p2371-2180-devkit.conf

(With r28.3, complete the above 2, the UART outputs logs after reboot)
But the log doesn’t go out from the UART-C and neither the screen.

Can somebody help.

2

hello HelloKittyWorld,

please check similar issue, Topic 1025894 for reference.
thanks

3

Hi Jerry:

I tried several times again with reference to “Topic 1025894”

First, I believe my HW is good by checking the ttyS2 function with R28.3.

And what I did are

  1. modified the p2371-2180.conf / p2371-2180-devkit.conf / jetson-tx1.conf
    CMDLINE_ADD=“console=ttyS2,115200n8 console=tty0 fbcon=map:0 net.ifnames=0”;

  2. revise the dts files, tegra210-jetson-common.dtsi / tegra210-jetson-cv-base-p2597-2180-a00.dts / tegra210-jetson-tx1-p2597-2180-a01-devkit.dts

     serial@70006200 {
 compatible = "nvidia,tegra210-uart", "nvidia,tegra114-hsuart";
 console-port;	
 status = "okay";

    };

But it still doesn’t work,
Could you help?
dmesg.txt (58.2 KB)

4

hello HelloKittyWorld,

please note that one of the UART is used for the Wi-Fi/BT on the Jetson TX1.
you may also refer to Jetson TX1 OEM Product Design Guide for details.

according to Jetson TX1 Module Data Sheet, in the footnote of the [UART Controller] chapter, could you please tried with two stop bits.
you may also check Topic 936285 for TX1 serial port configuration.
thanks

5

If you place an oscilloscope on the TX for the UART, do you see a lot of activity during boot? Or is this more or less holding its level?

6

Hi:

I apply the settings into mine

serial@70006200 {
    compatible = "nvidia,tegra210-uart", "nvidia,tegra114-hsuart";
     console-port;
     sqa-automation-port;
     enable-rx-poll-timer;
     status = "okay";
};

And check the signal on uart port.

There is nothing changed on the pins. (reboot the TX1 and check the uart signal )

Any other comment?

7

hello HelloKittyWorld,

could you please have workaround to disable nvgetty and warm-reboot the device.
for example,

sudo systemctl disable nvgetty.service

you may also check the script file at /etc/systemd/nvgetty.sh for details.
thanks

8

Hi:

Thanks.

I modify the description to ttyTHS2 in /etc/systemd/nvgetty.sh
then reboot.

My RS232 terminal shows the log-in prompt since the TX1 desktop shows and wait for around 1 minutes.

Is it possible to do more to make ttyTHS2 show boot log and the real-time printk messages?

9

I don’t know how much of this would apply (it is for TX2 in an earlier release, but probably very similar), but check this:
[url]https://devtalk.nvidia.com/default/topic/1025894/jetson-tx2/uart1-acts-as-default-debug-port-on-tx2-r28-1/post/5220368/#5220368[/url]

Note that some serial devices may be inherited by other serial devices in the Tegra line, and that a t186 refers to a TX2, while a t210 refers to a TX1. Also, actual procedure for installing a modified device tree changes across release versions, so you may need to look into device tree installation procedures.

Do make sure your serial UART is 3.6V TTL level. I tend to think of “RS-232” as the 9-pin D-Sub which uses alternate levels.

10

Hi:
Actually the combination of ttyS2 + (UART to USB adapter)works fine on my board with R28.3,
Unfortunately, it cannot work with R32.2.

Any further comment?

11

I have not actually tried to change this, so I have no real world test results. I’d probably start by comparing the device tree between the two versions. See if for example a controller address changed. Other drivers or config may have had significant changes between the two releases, but if in R32.2 you can at least get the UART working as just a UART, then you can probably go from there and get the serial console to also switch to that UART. I couldn’t tell you what the differences are between R28.3 and R32.2 for device tree on that particular UART.

12

Could someone help?

13

Hi:

I check the TX1-devkit with the raw L4T BSP,
I cannot get any boot-up message from the pin8/pin10 of J21.

Could someone help?

14

Is this the default device tree? Is your serial UART using 3.3V TTL levels? Are you using settings 115200 8N1 without flow control?

15

Hi:

This works for me