rpi3 and Adafruit GPS hat continued

[Per olof Ljungmark]

On 07/25/18 11:27, Per olof Ljungmark wrote:
> On 07/25/18 04:25, Warner Losh wrote:
>>
>>
>> On Tue, Jul 24, 2018 at 1:44 PM, Per olof Ljungmark <peo at nethead.se
>> <mailto: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
>>     <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.
> 
> Yes. Most importantly, stop the kernel from talking to the serial console.
> 
> I've been wandering around the source and right now the theory is to
> change /usr/src/sys/gnu/dts/arm/bcm283x.dtsi, it is the only place in
> all the included dts files where I find a reference to the console:
> 
>         chosen {
>                 stdout-path = "serial0:115200n8";
>         };
> 
> Says nothing about stdin though, not anywhere.

Tried stdout-path = ""; but that did not help.

I'm giving up and move to rpi2 and 11.2 instead. Phew.