On Tue, 2008-04-08 at 12:06 +0200, Stefan Roese wrote:
On Tuesday 08 April 2008, Joakim Tjernlund wrote:
I'm afraid, but the "other ppc's" did break with this patch. At least 4xx does. With your patch applied relocation to SDRAM does not work anymore. Here's what I get:
CFG_MONITOR_BASE=fffa0000 (ulong)&_start + EXC_OFF_SYS_RESET=fffa2200 EXC_OFF_SYS_RESET=100
I haven't looked into it closer yet. Any idea on how to fix this?
Thanks.
Best regards, Stefan
Oops, didn't see that coming. Your _start symbol in ppc4xx/start.S isn't pointing to your real start of execution. Seems like _start_440 is your real start but I can't be sure.
No, unfortunately it's not. _start_440 is loaded into the last 4k of bootrom (via linker script), since 440 has a shadow TLB upon startup to only map 4k of address space. After looking at System.map it seems that _start_of_vectors seems to be the way to go for 4xx:
fffa0004 T version_string fffa0100 t CritcalInput fffa0100 T _start_of_vectors
But I don't want to introduce some #ifdef here. Perhaps it would be better to introduce a common (PPC) label that points to the beginning of the U-Boot image here.
I first did a new symbol for this but changed it to use _start as I didn't want to introduce yet another symbol. I would hope it is possible to rework 4xx to move the _start symbol to were it belongs? Not having the _start symbol where it should be could bite you some other day too.
BTW: I think this version:
len = (ulong)&_end - ((ulong)&_start - EXC_OFF_SYS_RESET);
instead of:
len = (ulong)&_end - (ulong)&_start + EXC_OFF_SYS_RESET;
is better. Makes the transition from CFG_MONITOR_BASE clearer, don't you think so?
Sure, but I don't feel that strongly about it.