where can i get software datasheet?

I want to control gpio, and i dont know how to set it on OS? Where can i get software datasheet?

You may find this useful:
http://www.jetsonhacks.com/2015/12/29/gpio-interfacing-nvidia-jetson-tx1/

And in kernel source check out numeric assignments in:

arch/arm/mach-tegra/gpio-names.h

On a running JTX1 “/sys” has an interface which can export or unexport based on echo of the numeric GPIO ID into one of:

/sys/class/gpio/export
/sys/class/gpio/unexport

(be sure to “ls” in “/sys/class/gpio/” after an export/unexport to see how the sym links change)

Detailed information on GPIO hardware (but not explaining the Linux interface) is in the Technical Reference Manual (TRM…free login required):
https://developer.nvidia.com/embedded/downloads

Thanks for your help.BY the link, I know how to operate it, but i still have some question on it.
1、 “Signals on the header can be configured to run at 3.3V or 1.8V by shorting the appropriate pins on the J24 header”,how to configure it?
2、 Is there a way to get interrupt calls from GPIO input on the TX1? (instead of just polling them)
Look forward to your answer, thanks again.

There is physically a jumper on the developer carrier board. Default is 3.3V. If you look at the corner closest to the camera there is a 3-pin header with 0.1" spacing. The default jumper position uses 3.3V.

GPIO can be used as interrupts. Polling versus asynchronous is a kernel topic rather than specific to a Jetson…you can write your own driver such that it is called when the GPIO is triggered, and do whatever you choose when that happens (there are default behaviors to update sysfs exports, but you could make your own driver to do more).

Thanks a lot for your help.