On Fri, Apr 04, 2008 at 07:38:27PM +0200, Segher Boessenkool wrote: >>>> We really need to ack interrupts at mpic_teardown, since >>>> not all platforms reset mpic at kernel start-up. For example, >>>> kexec'ed kernel hangs on P.A. Semi if mpic_eoi() isn't called. >>>> >>>> Signed-off-by: Valentine Barshak <[EMAIL PROTECTED]> >>>> --- >>> >>> Would be interesting to find out why it hangs tho... it shouldn't . >> >> I haven't reproduced the problem and looked at hardware state yet, but >> I >> would expect it to be because the openpic won't send another interrupt >> until the previous is EOI'd, and the IPI is never EOI'd as far as I >> can tell. >> >> The XICS code does it explicitly already. I'm surprised it doesn't >> break >> on the 970-based platforms actually... > > platforms/maple/setup.c and platforms/powermac/pic.c use > MPIC_WANTS_RESET. > Is there a reason why we don't do that on every MPIC? If there is such > a reason, the default should be to reset, only pseries and chrp and cell > and now pasemi do not use it. It's the only sane way to get an MPIC > into > a sane known state starting from <whatever> state.
I used to have the reset there on pasemi but due to some other issues I ended up taking it out. It's not like doing a final EOI is a big deal, I really don't see why there's hassle about this patch. -Olof _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
