Re: Pi 4 serial ports

 Hi John,

On Mon, 9 Jan 2023 13:43:37 -0700
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

 In the rpi-firmware package there is some uartXX.dtbo
 By looking at them those overlays are there for enabling the other
uart port.
 Just put the ones you want to use on the FAT partition of your sdcard
in the /overlays/ directory and add in config.txt "dtoverlay=uartXXX"

 Cheers,

-- 
Emmanuel Vadot <manu@bidouilliste.com> <manu@freebsd.org>