public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
* Boot hang when setting console=none with MPC5200B custom board
@ 2010-04-22 18:58 Sylvain Lamontagne
  2010-04-22 19:11 ` Grant Likely
  2010-04-22 19:25 ` Albrecht Dreß
  0 siblings, 2 replies; 6+ messages in thread
From: Sylvain Lamontagne @ 2010-04-22 18:58 UTC (permalink / raw)
  To: linuxppc-dev@lists•ozlabs.org

Hi everybody,

I'm trying to remove the console from a custom board based on a
MPC5200B. During development we used console=3DttyS1,115200 in our bootcmd
for the kernel, but now that the product is ready to be shipped we want
to use ttyS1 for something else and would like to deactivate completely
the console. So the unit would be accessible only by ssh if needed.

(I'm not really confortable with this since a network problem would
prevent us of even debugging the platform... but I've been ask to do
it.)

Anyway, whenever I try to change console=3D to null or to tty1 or anything
else, the boot is hanging somewhere ( I know that, because some leds are
not flashing like they should on a normal boot and I can't login in with
ssh).

I've tried to use tty1, none, null, zero and I've tried to completely
remove the console=3D arguments... but nothing work, its hanging there
without any flashing leds.

I've tried redirecting another "real" serial port and it worked, so
console=3DttyPSC2,115200 work... but we need it also... so it can't do.

I've also tried the U-Boot's silent variable trick ... but it did not
work and I had to erase the environment of U-Boot with a JTAG to recover
back my default setting of ttyS1.

I'm now at a point where I think I have try everything that I know, and
since I have no way of "seeing" what is going on ... it's pretty hard to
debug.=20

The kernel is 2.6.29.2 and can't really be changed... (but it may be
patch)
This board doesn't have a framebuffer or a graphic chipset, everything
was done with a serial connection and now we want to remove this serial
connection (console) before sending it to a customer.

1. Is it possible ?
2. Do you have any idea how it can be achieve ?
3. Do you know a bug in 2.6.29.2 that could prevent this to work ?
4. The 'chosen' node is empty in my dts, does it require something to be
set ?

Thank you for your help ( I hope ;) )

Sylvain Lamontagne

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: Boot hang when setting console=none with MPC5200B custom board
@ 2010-04-23  7:28 Albrecht Dreß
  0 siblings, 0 replies; 6+ messages in thread
From: Albrecht Dreß @ 2010-04-23  7:28 UTC (permalink / raw)
  To: sylvain.lamontagne; +Cc: linuxppc-dev

Hi Sylvain:

> Humm I see, here is the node I'm creating in the initial ramdisk, so
> they are there before mdev is launched in one of my init scripts.
[snip]

I additionally have "tty0 c 4 0" which might be important here, plus a lot of other crap (should clean up there...;-).  I don't use a ramdisk, but have the /dev folder in the flash jffs2 image.  In the init script, I say

/bin/mount -t tmpfs ramfs /dev
mdev -s
mkdir /dev/pts
mkdir /dev/shm
chmod 1777 /dev/shm

and then tty0 is gone.  So to be honest I'm not absolutely sure it's necessary.

My inittab contains

::sysinit:/etc/init.d/rcS
::respawn:-/bin/sh 
::shutdown:/etc/init.d/rcS stop
::restart:/sbin/init
::respawn:/sbin/dropbear -F

With this, I can access the board through ssh (dropbear).  The dmesg output lists "console=tty0" as expected.  All PSC's are in the device tree, btw, and available as serial ports.

Hth,
Albrecht.

Traumziele - von Beschreibung bis Buchung jetzt kompakt auf den Reise-Seiten von Arcor.de! http://www.arcor.de/rd/footer.reise

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2010-04-23  7:29 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-04-22 18:58 Boot hang when setting console=none with MPC5200B custom board Sylvain Lamontagne
2010-04-22 19:11 ` Grant Likely
2010-04-22 20:34   ` Sylvain Lamontagne
2010-04-22 19:25 ` Albrecht Dreß
2010-04-22 20:23   ` Sylvain Lamontagne
  -- strict thread matches above, loose matches on Subject: below --
2010-04-23  7:28 Albrecht Dreß

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox