Re: Pi 4 serial ports

From: John Rushford <jjrushford_at_gmail.com>
Date: Tue, 10 Jan 2023 03:54:38 UTC
This is all new to me and after some digging, I’m currently trying to put together a rk3328-uart2.dtso that I can compile to an overlay file so as to enable uart2

John

> On Jan 9, 2023, at 1:43 PM, John Rushford <jjrushford@gmail.com> wrote:
> 
> Greetings,
> 
> I’m running FreeBSD 13.1-RELEASE on a raspberry pi 4b rev 1.4.  The pi 4 has 4 UART ports available but as far as I can tell, FreeBSD 13.1 only supports 1 of them.
> I would like to use one of the other UART ports to wire an adafruit GPS breakout too.  I tried using the UART0 port but when I wire the GPS breakout to it, 
> I run into boot issues with u-boot and console logging.  I know that in other OS’s such as raspian or ubuntu, you are able to enable the additional UARTS in config.txt.
> Thinking that FreeBSD might support this I tried adding “dtoverlay=uartx” where x is 0 to 3 but I’m not seeing in any kernel logging that these ports were enabled and
> I don’t see any additional ttyu’s in the dev tree.
> 
> So my question, does FreeBSD support these additional UARTS and if so, how do I enable them so that I may use one for the GPS breakout?
> 
> Thanks
> John