Not sure if we want similar text, maybe just something like "9600 is also common in some environments."

boot0 doesn't support above 9600?

Curious that this one already set ttyu0 to 115200

CC @debdrup

My guess is this doesn't matter much, I suspect either UEFI fw or the guest will set it in most cases.

It does. I've done 115200 with boot0.... But it's weird...
9600 is the fastest we can go with BIOS INT 0x14 routines.
and we do all our boot0 stuff using int 14 routines.
However, the system often initializes the serial port to 115200, and if you define BOOT_BOOT0_COMCONSOLE_SPEED=0, then it works because then your boot blocks won't touch the speed register.
And boot0 is little used anymore since it's MBR based.
And we have like 5 or 6 bytes left in the boot blocks, so rewriting to bang the hardware directly likely would overflow. We currently use ~20ish bytes for all serial interaction so 25 bytes would be hard to do read, write, poll and configure in...
Plus we're hard coded to COM1.
sio.o in boot2 is 90 bytes, so yea, we're stuck with this.
We don't document either one of these boot loaders currently (boot0 or boot0sio)

don't change this one, not even the comment. IT's legacy powerpc for booke which is somewhat on the obsolete end of the spectrum.

Ditto. Different variant of the same part used, I think, in old G3/G4/G5 macs.

Unsure why it does this...

These all likely need to be merged from /etc/ttys that we use for the whole system.
These are all off and 9600 due to the long, dead past... off is more important though.

This doesn't matter. dcons has no baud rate.

I've needed this forever :) But maybe we should keep this as 9600 to show how to get the old value :)

Yea, due to using int $0x14, we can't go faster than 9600.

Yeah, I just looked at all instances of 9600 and marked some of them to come back later for a second look.

IMO it's still better to have 115200 as a consistent value, even if not used.

It should be just as easy for someone to look at my updated example and understand what's needed to get 9600, as it is for someone to took at the old example and figure out how to get 115200 instead.

This file has moved.

So this should be ?= 9600 # No way to set baud rate 115200 via BIOS interfaces