I've been trying to get the watchdog timer to run in a 2.4.18 kernel
on our custom 750/8260 board. Finally I realised what was the problem
by disassembling with objdump. Due to the missing volatile declaration,
the dog kicking code
immr->im_siu_conf.sc_swsr = 0x556c;
immr->im_siu_conf.sc_swsr = 0xaa39;
gets optimised into this by gcc:
immr->im_siu_conf.sc_swsr = 0xaa39;
which don't make the dog happy.
Sorry if this is an old issue, I searched for it and couldn't find
anything. The patches for 2.4.18 does not contain this fix.
I don't know how it works but could someone who feel responsible change
the original source please?
Change from: extern immap_t *immr:
to: extern volatile immap_t *immr;
The actual variable declaration in 8260_io/commproc.c should probably
be volatiled to.
The system now boots with a 1.8s watchdog timer!
Cheers,
Hans
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