start_kernel does not get called on Virtex 4 FX 12 ppc 405

Thomas Glanzmann thomas at glanzmann.de
Thu Jun 21 22:33:03 EST 2007


Hello,
I still have the problem that embedded kernel boot loader "load_kernel"
is working but "start_kernel" is never reached AFAIT.  The last message
that I see is: "Now booting the kernel".

So I turned some LEDs on the Development board off in "load_kernel" and
tried to turn them back on in "start_kernel" I would like to know if
that still works. Or is not possible because the IO addresses are not
mapped via the MMU at the time. When I try to turn them back on in
"start_kernel"?

I used the following code:

*(volatile unsigned int *) (0x40000000 + 4) = 0x0;
__asm__ volatile ("eieio");
*(volatile unsigned int *) (0x40000000 + 0) = 0x0;
__asm__ volatile ("eieio");

First memory mapped io is direction register and the second call turns the leds
on/off. It works in the "load_kernel" routine.

        Thomas



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