On 16-Apr-00 Michael Engel wrote:
> I had some time over the weekend and started to hack on Linux for my
> good old R3000 Indigo (oh yeah, I should better try to write drivers
> for the PMAG-F and the FDDI adapter in my DECstations but Indigo
> hacking seemed to be more fun ;-)). I can load the kernel from sash
> and it actually starts at kernel_entry (whow) and - no wonder - crashes
> somewhere in init_arch (because I didn't change anything there ...).
> Now, it would of course be nice to have some kind of debugging output
> early on. Does anyone know if the R3k Indigo has the same ARCS console
> semantics as the Indy ? I.e. there is a PROMBLOCK struct at address
> 0xa0001000 (as defined in include/asm-mips/sgiarcs.h) which points to
> romvec which I can then use to dereference PROM functions ? Or is it
> something completely different ?
Well, as you can imagine I have absolutely no idea, but if you have a chance to
disassemble the beginning of the PROM (0xbfc00000) you can easily check if the
Indigo provides callbacks a la MIPS (very much like the DS3100).
If you find something like:
0: 0bf0008a j fc00228
4: 00000000 nop
8: 0bf0012a j fc004a8
c: 00000000 nop
10: 0bf0013f j fc004fc
14: 00000000 nop
18: 0bf0012c j fc004b0
1c: 00000000 nop
(and I wouldn't be surprised if you did) then you should have a look at
include/asm-mips/mipsprom.h and the startup code in arch/mips/dec/prom.