Enabling the correct UARTs on the Orin NX

[akhil.veeraghanta]

The default devkit device tree enables the following uart peripherals

[    0.262065] 31d0000.serial: ttyAMA0 at MMIO 0x31d0000 (irq = 63, base_baud = 0) is a SBSA
[    2.440742] usbserial: USB Serial support registered for FTDI USB Serial Device
[    2.453602] usbserial: USB Serial support registered for GSM modem (1-port)
[    5.798301] serial-tegra 3100000.serial: Adding to iommu group 2
[    5.804654] 3100000.serial: ttyTHS0 at MMIO 0x3100000 (irq = 17, base_baud = 0) is a TEGRA_UART
[    5.813961] serial-tegra 3130000.serial: Adding to iommu group 2
[    5.819368] 3130000.serial: ttyTHS3 at MMIO 0x3130000 (irq = 61, base_baud = 0) is a TEGRA_UART
[    5.828451] serial-tegra 3140000.serial: Adding to iommu group 2
[    5.834114] 3140000.serial: ttyTHS4 at MMIO 0x3140000 (irq = 62, base_baud = 0) is a TEGRA_UART
[    7.249999] systemd[1]: Created slice Slice /system/serial-getty.

• 3100000 - UART A
• 3130000 - UART D
• 3140000 - UART E

which is the mapping indicated by the technical reference manual

But AFAICT, UART0,1 and 2 are connected to the Orin NX

Which would be UART A, B, and C?

+    serial@3100000 {
+        status = "okay";
+    };
+
+    // UART B - UART 2
+    serial@3110000 {
+        status = "okay";
+    };
+
+    // UART C - UART 3
+    serial@c280000 {
+        status = "okay";
+    };

Turning those on, breaks flashing on our setup.

I wanted to check if those are the right peripherals to be turning on for the orin nx, because the ones enabled by default in the devkits device tree don’t seem to be correctly mapped.

[KevinFFF]

Hi akhil.veeraghanta,

What’s the carrier board in use for your Orin NX?
and the current Jetpack version?

Have your referred to the following instruction to enable uart through pinmux spreadsheet?
Jetson Orin NX and Nano Series — Changing the Pinmux

[akhil.veeraghanta]

We are using a custom carrier board on JP5.1.1, and yeah we updated the pinmux to turn on the peripherals.

But there were 3 serial periperhals broken out in the devkits device tree, and breaking out the same 3 did not work.

I figured those 3 would match up with the only 3 that are on the Orin NX

So adding

  // UART B - UART 2
 serial@3110000 {
        status = "okay";
 };

fixed our problem