On Sun, Jul 19, 2020 at 05:54:28PM +0200, Jaromír Doleček wrote: > Hello, > > I've implemented support for using MSI under NetBSD Dom0 with 4.11. > This works well. > > I have some trouble now with getting MSI-X work under Xen. > PHYSDEVOP_map_pirq hypercall succeeds just as well as for MSI, but > interrupts don't seem to get delivered.
How are you filling physdev_map_pirq for MSI-X? You need to set entry_nr and table_base. > MSI-X interrupts work with NetBSD for the same devices when booted > natively, without Xen. > > Can you give me some advice on where to start looking to get this > working? Is there perhaps something special to be done within the PCI > subsystem to allow Xen to take over? Are you enabling the capability and unmasking the interrupt in the MSI-X table? IIRC the OS also needs to unmask the entry in the MSI-X table in MMIO space, as done natively. There are also the Xen debug keys which can be helpful, take a look at 'i' and 'M'. Roger.
