Configure GPIO’s, UART’s, I2C and test for imx8mm Android OS kindly provide required documents for configuring.
for GPIO, maybe you can refer to the community document as reference
"https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/Accessing-GPIO-From-UserSpace/ta-p/11027..."
doesn't such document, but customer can refer to the dts file, then modify what you need according to the current bsp dts file
"https://source.codeaurora.org/external/imx/linux-imx/tree/arch/arm64/boot/dts/freescale?h=imx_5.4.70..."