Serial console only works after reboot?
nate at root.org
Sun Jan 4 15:11:12 PST 2004
On Sun, 4 Jan 2004, M. Warner Losh wrote:
> In message: <20040103233044.N17367 at root.org>
> Nate Lawson <nate at root.org> writes:
> : On Sat, 3 Jan 2004, M. Warner Losh wrote:
> : > In message: <20040103184934.V16815 at root.org>
> : > Nate Lawson <nate at root.org> writes:
> : > : I have a laptop (IBM T23) and use sio0 as my console/gdb port. One thing
> : > : I noticed is if I power up the laptop and boot -h, I get garbage out the
> : > : serial port. However, if I boot fully and then just warm reboot, the
> : > : serial console works fine. I'm only using 9600 bps. Ideas?
> : >
> : > weird. Is the garbage data at some different rate?
> : Nope, checked everything from 1200 up to 38400, different garbage but
> : always garbage. This is with -current as of 2003/12/30, no patches.
> Try 115200.
That works. Now the question is "why". Note that I have no "options
CONSPEED" so according to /sys/dev/sio/sioreg.h, it should default to 9600
and indeed does, after a reboot. But not on a cold startup.
More information about the freebsd-current