On Wed, Nov 5, 2014 at 6:58 PM, Yijing Wang <wangyijing@xxxxxxxxxx> wrote: >>> +{ >>> + return (irq_hw_number_t)msidesc->msi_attrib.entry_nr | >>> + PCI_DEVID(pdev->bus->number, pdev->devfn) << 11 | >>> + (pci_domain_nr(pdev->bus) & 0xFFFFFFFF) << 27; >> >> Where does this bit layout come from? Is this defined in the spec >> somewhere? A reference would help. > > Currently, more and more Non-PCI device use MSI(or similar MSI mechanism), like DMAR fault irq > and HPET FSB irq. And we have to add additional code to support the MSI capability. > So I hope we can decouple MSI code and PCI code, then we can unify all MSI(or Message Based interrupt) > in one framework. Was that supposed to answer my question? If so, I didn't understand how it explains where the bit layout came from. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html