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Problem rebooting the AMD SC520.

Hi,

We are currently running Linux (Red Hat 6.2) on a card with AMD SC520. We use rolo to boot a 2.2.12 kernel and everything works quite good, except for rebooting the card.

When I run the Linux command 'reboot' it finally comes to a function in the kernel called machine_restart (in linux/arch/i386/kernel/process.c). This function tries to reset the processor in a number of ways. I've added a call for setting the CPU_RST bit in SYSCTLA register but this doesn't seem to work either. I've also tried to generate the triple-fault before everything else.

The processor doesn't start from the reset vector at 0xFFF1, like it does when we disconnect and connects the power.

I wan't to do a complete reset of the processor and that must the purpose of machine_restart, isn't it? Anyone that recognises this or perhaps knows what the problem might be?

Glad for any help I can get.

Reply to
Martin Kvarmo
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^^^^^^ Shure? Should be 0xFFFFFFF0 (consider real mode and the trick with the descriptor base register).

Try set RESCFG to 0x0C, before setting CPU_RST in SYSCTLA. And don't forget to reset the PCI bus (while you wake up after such kind of reset), if you have a device that could be a master on the bus.

Hope it helps.

--
Juergen Beisert        email: jbeisert _AT_ eurodsn _DOT_ de
EuroDesign embedded technologies GmbH  http://www.eurodsn.de
Reply to
Juergen Beisert

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