(This note is amd64-centric.)
I am simultaneously struggling with console selection issues on an apu2
(has only serial, non-xen) and regular amd64 (no serial ports wired up,
xen). I find that sometimes I have console output but not input
(console=pc, under Xen, when in ddb, USB keyboard).
I've been rototilling the HOWTO again:
https://wiki.netbsd.org/ports/xen/howto/
(I demoted the "converting from grub" section to the grub graveyard page,
but I think nobody will be bothered.)
More importantly, I adjusted the install section about boot configs a
fair bit.
As I understand things and don't understand things:
mbr_bootsel uses BIOS calls so it uses the BIOS's notion of console,
working on keyboard/vga (which I'll call normal), and also on the
apu2's serial port.
bootxx_ffsv1 (and similar) can be configured for a console.
\help Why doesn't bootxx use the same BIOS calls as MBR, so that
it doesn't need configuring? (Or maybe it does, but the config is
about controlling /boot and then the kernel?)
\help Is bootxx config passed to /boot, and on to the kernel?
boot_console(8) seems to say so, but the docs for the later config
doesn't seem to say that normally, one wouldn't need to configure
booting in other than bootxx.
\help boot_console(8) doesn't say this, but the build lines for some
boot stuff make it look like params are passed:
-DSUPPORT_SERIAL=boot_params.bp_consdev
/boot can be configured in boot.cfg, by the consdev command.
\help How does one set baud rate and parity with consdev? Reading the
boot2.c, it looks like "consdev com0:9600".
\help boot.cfg(5) documents consdev but uses also console= in examples
without explaining. Is the distinction that consdev controls how
/boot behaves and console= is a config for what is booted?
\help Is there any difference between using consdev on a menu line and
placing it on a line by itself, to always be in effect? (To be,
choice of console is primarily about which kind the machine has, and
only secondarily to use serial sometimes.)
\help Given that "pc" is the standard approach, why do examples give
console=pc?
\help Given that xen finds a console, and provides xencons(4) to the
dom0, why isn't the standard approach to let the dom0 console use
xencons?
And not about console:
Reading boot.cfg, one finds that the -s for single user belongs with
the load statement as it's the dom0 kernel that is to be booted single
user, not the xen kernel. Is this right?
menu=Xen single user:load /netbsd-XEN3_DOM0.gz console=pc -s;multiboot /xen.gz dom0_mem=512M
\help None of the examples show rndseed. But this issue would seem to
apply to dom0 just as it would apply to booting GENERIC not under Xen.
Is this just a case of the examples not catching up with current
practice?
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