> Also, from the Akaros side, we've extended the Plan 9 MSI code to
> support MSI-X and tested it on real hardware; works fine. This allowed
> us to stop worrying about ACPI; you don't need it if you do MSI-X.
> Relief! And MSI-X is in some ways easier than MSI.
i don't see how this could be the case for some pretty common hardware.
for example, i have yet to see a usb controller that will do either
msi or msi-x.
for example, on this machine (random intel)
; pci |grep usb
0.26.0: usb 0c.03.20 8086/1c2d 11 0:fbc23000 1024
0.29.0: usb 0c.03.20 8086/1c26 5 0:fbc22000 1024
; pci -vc 0.26.0 0.29.0
0.26.0: pwrmgmt/01 dbgprt/0a advfeat/13
0.29.0: pwrmgmt/01 dbgprt/0a advfeat/13
nope. it's i/o apic interrupts for me! unless there's some magic way
to convert i/o apic into msi-x that i don't know about. hoping this
is the case....
- erik
