No. legacy_irq->nr_legacy_irqs is just for dealing with hardware that
does not have i8259 pics.
Here I am reserving 16 irqs above the gsi range in case we get a
weird gsi to isa irq mapping.
Currently the sfi spec doesn't mention anything explicitly. I
took a quick read through it and sfi and I presume Moorestown
is talking about non pci irqs. So I would not be surprised
if we didn't have isa device drivers running on platforms
without i8259s.
Currently the code had a small bug dealing with multiple ioapics and
the spec really is incomplete about how you map irqs from pci devices
to interrupts. So it looks like SFI and Moorestown are more a lab
experiment than real hardware at the moment. So I expect when
it gets completely fleshed out we will have to jump through a
similar set of hoops as we do with acpi to ensure the first 16
irqs are not used for anything except isa irqs.
Eric
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