02-04-2019 02:14 PM
I tried to add a UART IP to my Zynq board. First I added an axi_uartlite IP and built FPGA and Linux image, but I couldn't see any TTY device created under /dev/ttyxx. Then I added an axi_uart16550 IP and rebuilt FPGA and Linux image. I saw 4 TTY devices were created. But I tested these 4 TTYs, only ttyS3 worked. Please see the attached screen shot. Can any one help to explain this and guide how to create a UART device and tty driver. Thanks!
02-07-2019 07:36 AM
Make sure you enable axi uartlite driver in menu config to see ttyULx in the list.
02-07-2019 02:33 PM
Thanks for reply! I will try this. Is the CONFIG_SERIAL_UARTLITE variable already in some .config file? I couldn't find it.
# integrate into the kernel
In addition, this potentially solves my first part of issues. My second part is why axi_uart16550 IP would create 4 device? Please see my design and question screen shot.
02-07-2019 09:21 PM
Try root@zcu102:~# dmesg |grep serial and see what result you are getting back.
02-07-2019 09:35 PM
To add more along with pvenugo, could you please check whether driver got probed as mentioned in wiki
02-11-2019 09:38 AM
Thanks suggstions. You can see if I run ls /dev/tty*, I would see 4 devices. However, if run dmesg | grep serial, only one.