x86: Documentation/i386/IO-APIC.txt: fix description

The description of the interrupt routing doesn't match the (nice) diagram.

Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Nick Andrew 2008-03-04 15:05:40 -08:00 committed by Ingo Molnar
parent 5254149f6c
commit c0c20fb5a8

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@ -70,7 +70,7 @@ Every PCI card emits a PCI IRQ, which can be INTA, INTB, INTC or INTD:
These INTA-D PCI IRQs are always 'local to the card', their real meaning
depends on which slot they are in. If you look at the daisy chaining diagram,
a card in slot4, issuing INTA IRQ, it will end up as a signal on PIRQ2 of
a card in slot4, issuing INTA IRQ, it will end up as a signal on PIRQ4 of
the PCI chipset. Most cards issue INTA, this creates optimal distribution
between the PIRQ lines. (distributing IRQ sources properly is not a
necessity, PCI IRQs can be shared at will, but it's a good for performance