Software watchdog timer doesn't work for 860P , using ppcboot and 2.4 linux

[John Francis]

Hello,

I am having a problem using the software watchdog
feature. My board has 860 running at 80Mhz.

When I enable software watchdog using CONFIG_WATCHDOG
in my board config*.h file for PPCBoot, the system
resets while decompressing the ramdisk.

I have used the patch that modifies the 2.4.X kernel
that was posted while back. on ppcboot mailing list.

Ref. url -

http://www.geocrawler.com/archives/3/4205/2001/7/50/6264938/


If I use the patch mentioned above, but don't enable
the software watchdog, in bootrom, I can see that the
timer interrupt is getting called and everything in
patch above looks like it works.

It seems like some where before the timer_interrupt is
installed/enabled in 2.4.x kernel watchdog is going
off.

Before I go and look into hacking away at head_8xx.S
file in directory linux/arch/ppc/kernel
I thought I would ask folks who know more. Should code
in mpc_8xx.S take more than 1.5 seconds to execute on
80Mhz 8xx?

I tried inserting code that "resets" the software
watchdog in start_kernel routine, but that too didn't
help.


Now if I want to insert the code that resets the
software watchdog timer, what is the most "time
consuming" operation?

Any help pointers will be much appreciated.

John.


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