[U-Boot-Users] lowlevel init and reboot issue

Roman Kolesnikov romank at randrlabs.com
Fri Jul 7 02:59:56 CEST 2006


Hello,

I am running a board similar to the at91rm9200ek board. It has been 
stripped down of few peripherials for minimal power consumption purpose. 
I am running uboot 1.1.4 and linux 2.6.16. U boot loads directly from 
parallel flash into ram.

My problem is that I cannot restart the chip from linux. I followed the 
watchdog code, and it does execute. Linux also closes up fine. However, 
the processor does not reset at the end. The weird thing is that a reset 
works fine from uboot. The code is almost identical between the uboot 
reset and the linux system call. Both set the reset pin and make a 
watchdog overflow.

I believe that my issue lies in a uboot setting somewhere in the initial 
linux setup. If I load ubott 1.1.4 without low level init by means of 
yet another loader loading uboot from flash to ram, the reset runs but 
very slow. However, my uboot utilizes the lowlevel init. Somehow it 
affects my watchdog timer and stops me from resetting the chip.

Has anyone run into this issue? What could be stopping me from resetting?

I thought that the watchdog timer was a purely hardware tool. I thought 
that setting and overflowing the timer would reset the chip on a 
hardware level. Please help. I have spent a week or so on this and 
cannot figure out the issue. It is probably very simple and is my 
oversight, however, I cannot see it yet.

Thanks again,
Roman




More information about the U-Boot mailing list