On Thursday 21 May 2009, Paul Brook wrote: > > > MSI provides multiple edge triggered interrupts, whereas traditional > > > mode provides a single level triggered interrupt. My guess is most > > > devices will want to treat these differently anyway. > > > > So, is qemu_send_msi better than qemu_set_irq. > > Neither. pci_send_msi, which is a trivial wrapper around stl_phys.
To clarify, you seem to be trying to fuse two largely separate features together. MSI is a standard PCI device capability[1] that involves the device performing a 32-bit memory write when something interesting occurs. These writes may or may not be directed at a APIC. The x86 APIC has a memory mapped interface that allows generation of CPU interrupts in response response to memory writes. These may or may not come from an MSI capable PCI device. Paul [1] Note a *device* capability, not a bus capability. _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linux-foundation.org/mailman/listinfo/virtualization
