How to know correct IRQ number for calling request_irq() while writing myown Linux driver?

hi!!
Do you finish your work on writing your UART driver of Linux?
I have a board based on Cyclone V SoC, the board has a UART module on the FPGA side, I have to write a drive for the UART, but I am a beginner in Linux, it’s too hard for me to write a drive.
So, Can you share your UART driver with me? Thanks a lot!
my email address is heuyang@163.com!