Re: MPC83xx console : no output after handover

["Matthew L. Creech" <mlcreech@gmail.com>]

On Tue, Mar 31, 2009 at 5:26 PM, Gary Thomas <gary@mlbassoc.com> wrote:
>
> The fact that you get the ttyS1 line printed is interesting. =A0At
> this point, the kernel is switching from raw console I/O (only
> suitable for bring-up messages) to the general serial driver
> (interrupt driven, etc). =A0I'm curious about what the ttyS1 driver
> is causing to break...
>
> A couple of things you could try:
> =A0* Disable ttyS1 (take it out of your device tree)

I tried taking ttyS1 out - the results are no different (other than
the fact that "console handover" is now the last line that prints).
My debug printk()s at the end of 8250_init() show up, which would seem
to imply that ttyS0 was initialized correctly, so I'm not sure what
else could be stomping on it.

> =A0* Look at the console log when this happens. =A0Look in your system
> =A0 =A0map for the symbol '__log_buf', e.g.
> =A0 =A0 =A0 c031ca54 b __log_buf
> =A0 =A0This will get stored at physical location '0x31ca54' and will
> =A0 =A0often contain data that didn't get a chance to print, for example
> =A0 =A0if you have stuck interrupts that prevent the console from working=
.
> =A0 =A0I'd just run it to this point and then examine the memory - either
> =A0 =A0using a BDI if one is attached, or press RESET (I hope you have on=
e!)
> =A0 =A0and then look using your boot loader (uBoot, RedBoot, ...)
>

I think I can get my hands on a BDI tomorrow, so I'll give this a try
then.  Thanks for the reply

--=20
Matthew L. Creech