On 06-Jun-2003 M. Warner Losh wrote: > In message: <XFMail.20030606141331.jhb_at_FreeBSD.org> > John Baldwin <jhb_at_FreeBSD.org> writes: >: I have a small tweak to the PCI code that re-routes PCI interrupts. >: Basically, it does two things, 1) make the comment less ia64-specific >: and 2) if the interrupt route returns an invalid IRQ (i.e. 255), then >: we don't change the intline. In other words, if we can't route the >: interrupt, we just assume that the firmware knows more than we do and >: go with the value it stuck in the register. 1) is a no-brainer, but >: I wonder what people think about 2). Patch below: > > I think #2 isn't so good. #1 is a no-brainer :-) > >: #if ... > ... >: + irq = PCIB_ROUTE_INTERRUPT(pcib, dev, cfg->intpin); >: + if (PCI_INTERRUPT_VALID(irq)) >: + cfg->intline = irq; >: + else >: #endif >: + irq = cfg->intline; >: + resource_list_add(rl, SYS_RES_IRQ, 0, irq, irq, 1); >: } >: } > > The part I don't like is that if we can't route an interrupt, we > assume that the interrupt that was written there before is good and > routed. This strikes me as an unwise assumption. I don't strongly disagree. Hence my request for comments. I've been of both minds on this one and just want to see what the consensus is. > Also, we haven't > recorded our info in the underlying pci register. Don't know if that > will matter for other OSes that are booted after we are. Don't think it matters as far as reboots, but I do think that this code should write the updated intpin to the actual config register. -- John Baldwin <jhb_at_FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/Received on Fri Jun 06 2003 - 10:04:45 UTC
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