uart(4) on stable/7

[Matthew Fleming]

I am interested in using uart(4) instead of sio(4) on stable/7, to ease
our eventual transition to stable/8 or CURRENT.  I added device uart and
changed up /boot/device.hints (there were no entries in /etc/ttys that
mentioned sio), and I get something that boots and has messages on the
console, up to the login prompt.

There's no login prompt, though.

I can ssh to my box, echo to /dev/console appears on the console;
messages on reboot appear on the console, just not the login prompt.
Does anyone know what else I may be missing to use uart(4)?

Also, we have some boot scripts locally that will try to set
machdep.conspeed based on hardware type; uart(4) doesn't seem to expose
a sysctl by that name.  How does the uart driver for stable/7 deal with
differing console speeds?

The hints in /boot/device.hints, obtained by s/sio/uart:

hint.uart.0.at="isa"
hint.uart.0.port="0x3F8"
hint.uart.0.flags="0x90"
hint.uart.0.irq="4"
hint.uart.1.at="isa"
hint.uart.1.port="0x2F8"
hint.uart.1.irq="3"
hint.uart.2.at="isa"
hint.uart.2.disabled="1"
hint.uart.2.port="0x3E8"
hint.uart.2.irq="5"
hint.uart.3.at="isa"
hint.uart.3.disabled="1"
hint.uart.3.port="0x2E8"
hint.uart.3.irq="9"

Thanks,
matthew