[U-Boot] [PATCH] powerpc: do not fixup NULL ptrs

Andre Schwarz
2010-11-04T10:00:52Z

Jocke,

[snip]
>> finally I got both some time and hardware :
>>
>> 4 nops after _start does the trick, i.e. the board is up and running fine.
>>
>>
>> Diffing both System.maps and U-Boot hexdump gives only trivial results :
>>
>> - "in_flash" and "_start_of_vectors" adress increment = 0x10.
>> - offset calculation for relative branch instruction also increases by 0x10.
>>
>>
>> Let me know if you need more information or something else tested.
>>
> How is this going? If nothing else I think you should send
> a patch for 83xx, adding the 4 nop's as your(and mine) board is
> broken otherwise. Freescale guys seems busy with other things so
> I think this is the best thing to do.
>

currently I can see no light at the end of the tunnel so that I don't
dare send any kind of patch.

Actually I got some time to analyze and further optimize the memory bus.
During relocation the board hangs in flush_dcache.
I can see the DDR-II signal levels change to a non-working state ...
maybe this is caused by some internal reset - don't know.

But approx. 1 out of 20 tries (power cycles) U-Boot makes it past that
point and continues working.
Then there's a console and the system is memtesting for hours. PCI, LAN
and Flash are also running fine.
No issues after flush_dcache succeeded.

Second strange issue is that the serial line is dead again as soon as I
#define USB functionality withing board config, i.e. U-Boot does not
even run from flash.
This is reproducable - removing the USB #defines makes U-Boot work again.

Removing the 4 "nop" doesn't help either.

I definitely need some time to dig a little deeper.

Any help or pointers are welcome.

Regards,

Andr?

MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler
Registergericht: Amtsgericht Stuttgart, HRB 271090
Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner