Agx Orin - Some GPIO pins could not configured as 'Bidirectional'

[annaprabu.r]

Hi,

We have developed custom carrier board based for Jetson AGX ORIN(32GB). In that, Some of the GPIO pins can be configured only as ‘Output’ direction not as Input/Bidirectional.

JetPack - 5.1.1 (L4T35.3.1)
GPIO Pins(can’t configure as bi-directional) - GPIO3_PR.02(K53)
- GPIO3_PH.03(L5)
- GPIO3_PH.05(L4)
- GPIO3_PY.05(C58)
- GPIO3_PY.07(G58)

We would like to use these pins as bidirectional. Is that possible to use those pins as bidirectional?

[KevinFFF]

Hi annaprabu.

How did you configure these pins in pinmux spreadsheet?

How do you verify it could not configured as “bi-directional”?
Could you share the steps you used to verify?

[annaprabu.r]

In pinmux sheet, If I changed pin direction from ‘Output’ to ‘Bidirectional/Input’, it shows an error “GPIO3_PR.02 Should not be set as Bidirectional/input”. So, I have manually changed the pinmux in the dtsi file as below.

i configured these gpio as input and loopback with another output gpio (set output value as high). if i read the input gpio value , it always show as LOW.

/* dtsi */
Example:

uart1_tx_pr2 {
		nvidia,pins = "uart1_tx_pr2";
		nvidia,function = "rsvd1";
		nvidia,pull = <TEGRA_PIN_PULL_NONE>;
		nvidia,tristate = <TEGRA_PIN_DISABLE>;
		nvidia,enable-input = <TEGRA_PIN_ENABLE>; /* Changed */
		nvidia,lpdr = <TEGRA_PIN_DISABLE>;
	};

uart4_tx_ph3 {
	nvidia,pins = "uart4_tx_ph3";
	nvidia,function = "rsvd2";
	nvidia,pull = <TEGRA_PIN_PULL_NONE>;
	nvidia,tristate = <TEGRA_PIN_ENABLE>;
	nvidia,enable-input = <TEGRA_PIN_ENABLE>;/* Changed */
	nvidia,lpdr = <TEGRA_PIN_DISABLE>;
};

uart4_rts_ph5 {
	nvidia,pins = "uart4_rts_ph5";
	nvidia,function = "rsvd2";
	nvidia,pull = <TEGRA_PIN_PULL_NONE>;
	nvidia,tristate = <TEGRA_PIN_DISABLE>;
	nvidia,enable-input = <TEGRA_PIN_ENABLE>;/* Changed */
	nvidia,lpdr = <TEGRA_PIN_DISABLE>;
};

uart5_tx_py5 {
	nvidia,pins = "uart5_tx_py5";
	nvidia,function = "rsvd1";
	nvidia,pull = <TEGRA_PIN_PULL_NONE>;
	nvidia,tristate = <TEGRA_PIN_DISABLE>;
	nvidia,enable-input = <TEGRA_PIN_ENABLE>;/* changed */
	nvidia,lpdr = <TEGRA_PIN_DISABLE>;
};

uart5_rts_py7 {
	nvidia,pins = "uart5_rts_py7";
	nvidia,function = "rsvd1";
	nvidia,pull = <TEGRA_PIN_PULL_NONE>;
	nvidia,tristate = <TEGRA_PIN_DISABLE>;
	nvidia,enable-input = <TEGRA_PIN_ENABLE>;/* Changed */
	nvidia,lpdr = <TEGRA_PIN_DISABLE>;
};

[KevinFFF]

@annaprabu.r

In pinmux sheet

Are you using v1.8 Jetson_AGX_Orin_Series_Pinmux_Config_Template.xlsm?

It seems I could configure PR.02 as following:

			uart1_tx_pr2 {
				nvidia,pins = "uart1_tx_pr2";
				nvidia,function = "rsvd1";
				nvidia,pull = <TEGRA_PIN_PULL_NONE>;
				nvidia,tristate = <TEGRA_PIN_DISABLE>;
				nvidia,enable-input = <TEGRA_PIN_ENABLE>;
				nvidia,lpdr = <TEGRA_PIN_DISABLE>;
			};

Could you try to remove Drive 0 in Req. Initial State?

[annaprabu.r]

Yes, I’m using v1.8 of Jetson_AGX_Orin_Series_Pinmux_Config_Template.xlsm.

I can configure PR.02 as ‘bidirectional’ by using spreadsheet but it was not working as input. Even, other GPIO’s (PH.03, PH.05, PY.05 and PY.07) can’t be configure as bi-directional in Spreadsheet as well as dtb(The changes was not reflected) .