Grant Grundler wrote: > On Sun, May 27, 2007 at 06:03:29PM -0700, Roland Dreier wrote: > ... >> > I can imagine many systems where the cpu simply doesn't have enough >> > interrupt pins to uniquely identify every possible MSI interrupt >> > source. >> >> I have a hard time imagining a PCI host bus controller that converts >> MSI interrupts back to wire interrupts that go to pins on the CPU. >> For one thing it would be hard to maintain the guarantee that >> MSI interrupts can't pass DMAs. > > Whatever converts the MSI back to CPU IRQ pins would have to participate > in the "cache coherency domain". This would avoid issues around DMA ordering. > It _could_ be on the same silicon as the PCI Host bus controller as long > as the above is true. >
Also, don't forget that a lot of platforms provide *no* hardware cache coherency. -hpa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/