SiS630 Software Watchdog Timer

Steve Gehlbach steve at
Sun Mar 16 20:14:00 CET 2003

Spirit wrote:
>   I've been reading the SIS630 datasheet and found out that the
>   chipset has a watchdog timer (for some reason they call it
>   'software') similar to that of the i810.
>   Does anybody here know if there is a ready driver for that thing?

Not aware of a linux driver, but you might want to turn off the software 
watchdog earlier, if you use compression.  Right now it is disabled in 
southbridge.c which is too late since decompression takes a few seconds.

This will do it in

#define ACPI_BASE_ADDR          0x5000

         /* Disable Auto-Reset */
         movw    $(ACPI_BASE_ADDR + 0x56), %dx
         inb     %dx, %al
         orb     0x40, %al
         outb    %al, %dx

         /* Disable Software Watchdog */
         xorb    %al, %al
         movw    $(ACPI_BASE_ADDR + 0x4b), %dx
         outb    %al, %dx

There are some other simplifications that can be put into 
(the gdt reload is not necessary after the Eric's changes in c_start.S), 
but I haven't had time to make a diff and send it to Ron.


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