Re: Pi 4 serial ports

From: Mark Millard <marklmi_at_yahoo.com>
Date: Tue, 10 Jan 2023 04:49:10 UTC
On Jan 9, 2023, at 19:54, John Rushford <jjrushford@gmail.com> wrote:

> 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

I'm confused. A rk3328 is a rockchip part not involved in/for
RPi*'s (broadcom parts). Examples of .dtb files for products
using the rk3328 parts are:

/boot/efi/dtb/rockchip/rk3328-rock64.dtb
/boot/efi/dtb/rockchip/rk3328-nanopi-r2s.dtb
/boot/efi/dtb/rockchip/rk3328-rock-pi-e.dtb

.dtbo files for a rk3328 are not usable for RPi*'s
generally (ever?).

Are you now using a rk3328 based part instead of a
RPi* ?

> 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


===
Mark Millard
marklmi at yahoo.com