share their IRQ lines with the i8042. Any IRQ activity (typically during
attach) on the NS16550 used to connect the keyboard when actually the
PS/2 keyboard is selected in OFW causes interaction with the OBP i8042
driver resulting in a hang (and vice versa). As RS232 keyboards and mice
obviously aren't meant to be used in parallel with PS/2 ones on these
boards don't attach to these NS16550 in case the RS232 keyboard isn't
selected in order to prevent such hangs.
Ok'ed by: marcel