On Wed, 23 May 2018, Robert Swindells wrote:
I now get the following, not sure yet what is causing the garbage output from locore:
I would guess you either have a misconfigured clock / baud rate, or you are not properly checking TX FIFO status before writing in your platform early_putchar impl.
For the latter, have a look at the meson8b code, I expect it is similar to your SoC in this regard:
https://nxr.netbsd.org/xref/src/sys/arch/evbarm/amlogic/amlogic_machdep.c#267