Problems restarting after watchdog

Problems restarting after watchdog

[Paul Chernett]

Hi,
	we're running linux from RedBoot on an Intel IXP425 board. When the
watchdog in the IXP425 fires RedBoot often fails to start up and restart
Liux - everything just hangs.

Any ideas?

Paul Chernett
Grandeye Ltd.

Re: Problems restarting after watchdog

[Andrew Lunn]

On Wed, Dec 22, 2004 at 07:51:27AM -0000, Paul Chernett wrote:
> Hi,
> 	we're running linux from RedBoot on an Intel IXP425 board. When the
> watchdog in the IXP425 fires RedBoot often fails to start up and restart
> Linux - everything just hangs.

I've had a similar problem on another target. Sometimes after a
watchdog reset the board did not boot. This turned out to be a
hardware design error. The flash devices were not getting reset. This
meant if a flash erase/program was going on when the watchdog went
off, the flash remained unaccessable and the device could not boot.

The same could be happening with your system. Some device is not
getting reset back to power on state causing the system to not boot
correctly.

        Andrew

RE: Problems restarting after watchdog

[Paul Chernett]

The problem turns out to be that the IXP425 doesn't have an external reset
pin so external devices - especially flash aren't reset when the watchdog
fires leading to the situation you describe.

Our solution will be to use an external watchdog device.

Thanks.


> -----Original Message-----
> From: Andrew Lunn [mailto:andrew@lunn.ch]
> Sent: 22 December 2004 08:29
> To: Paul Chernett
> Cc: ecos-devel@sources.redhat.com
> Subject: Re: Problems restarting after watchdog
>
>
> On Wed, Dec 22, 2004 at 07:51:27AM -0000, Paul Chernett wrote:
> > Hi,
> > 	we're running linux from RedBoot on an Intel IXP425 board. When the
> > watchdog in the IXP425 fires RedBoot often fails to start up and restart
> > Linux - everything just hangs.
>
> I've had a similar problem on another target. Sometimes after a
> watchdog reset the board did not boot. This turned out to be a
> hardware design error. The flash devices were not getting reset. This
> meant if a flash erase/program was going on when the watchdog went
> off, the flash remained unaccessable and the device could not boot.
>
> The same could be happening with your system. Some device is not
> getting reset back to power on state causing the system to not boot
> correctly.
>
>         Andrew
>