rpi3 and Adafruit GPS hat continued

[Warner Losh]

On Tue, Jul 24, 2018 at 1:44 PM, Per olof Ljungmark <peo at nethead.se> wrote:

> Thanks to
> http://freebsd.1045724.x6.nabble.com/Adding-a-GPS-Module-hat-shield-on-a-
> Raspberry-Pi-td6236680.html
> and helpful people on the list I managed to get the pi to boot by
> silencing the console messages in u-boot.
>
> I skipped the switch and patched rpi.h:
>
> @@ -85,10 +87,13 @@
>  #define CONFIG_INITRD_TAG
>
>  /* Environment */
> +#define CONFIG_SYS_DEVICE_NULLDEV
> +#define CONFIG_SILENT_CONSOLE_UPDATE_ON_RELOC
> +#define CONFIG_SILENT_CONSOLE_UPDATE_ON_SET
>  #define ENV_DEVICE_SETTINGS \
> -       "stdin=serial,usbkbd\0" \
> -       "stdout=serial,vidconsole\0" \
> -       "stderr=serial,vidconsole\0"
> +       "stdin=usbkbd\0" \
> +       "stdout=vidconsole\0" \
> +       "stderr=vidconsole\0"
>
> and now the pi is booting.
>
> Now to the next problem, I need to rewire TXD and RXD and add reception
> of the PPS signal on pin 4. The advice in the link above is not
> appclicable to current and rpi3.
>
> Right now uart1 is wired to the RXD and TXD pins, I want uart0. Is it
> recompile a dts or use gpioctl?
>
> uart0: <PrimeCell UART (PL011)> mem 0x7e201000-0x7e201fff irq 24 on
> simplebus0
> uart1: <BCM2835 Mini-UART> mem 0x7e215040-0x7e21507f irq 32 on simplebus0
> uart1: console (115200,n,8,1)
>

I'm pretty sure that you'll need to hack dts.

Warner