Gpio changes

What does the third step as shown in the picture mean?
Why does GPIO3_PBB.00 belong to the main Jetson GPIO group and its port number is 21?
In step 5, why does PBB00 belong to the tegra-gpio group?

thank you!!

There is no special reason. Just a spec over the TX2 SoC.

Refer to the header file for information.

I have seen this header file, but I don’t know its corresponding relationship. For example, Customer Usage is “GPIO3_PBB.00”, why is “#define TEGRA_MAIN_GPIO_PORT_BB 21” corresponding to the header file

The formula in the document is to teach you how to calculate the gpio number. The linux system uses the gpio number to know which pin you are talking about.

For example, if I want to use GPIO pin BB.00, then how should I calculate the gpio number and tell the system. The result will be 488 for GPIO pin BB.00.

I understand, what I want to ask is how to get the value of “base, port and pin” in the formula, why does GPIO3_PBB.00 correspond to port=21 instead of “#define TEGRA186_MAIN_GPIO_PORT_CC 22”?
And GPIO3_PBB.00 belongs to tegra-gpio, not tegra-gpio-aon

It has no reason. Just the spec. You need to follow the header file to know these numbers.

If it is a specification, in which document is it described? Please send the document, but I can’t find it!

I don’t know what you want to do here. I mean. This is just a number for you to use GPIO.

Why does how this number work bothers you? You want to change the number?

for example: If I want to know how many GPIOs the Customer Usage is “DSI_A_CLK_N”, how do I calculate it?

First, check the pinmux spreadsheet and see if this pin could be a gpio. If so, what is the pin ID of this GPIO…

Given any pin that can be GPIO, and calculating GPIO according to the formula, I want to know how the port in the formula is found from the tegra186-gpio.h file? I know this is a rule, where is this rule? Why the port of GPIO3_PBB.00 is 21, not 22

The TRM is over here every controller on this SoC should be listed in the TRM.

Thank you, I’ll try to find it!

how to get a pin mapping.pdf (550.0 KB)