pci_host_generic_acpi: use NUMA node when allocating MSI/MSI-X

[jchandra]

Summary

Use NUMA node info obtained from _PXM call to generate the XREFs used while allocating MSI/MSI-X interrupts.

This allows us to register the LPIs with the GIC ITS block on the same node.

The ACPI IORT table (from ARM) has to be decoded to do a complete implementation. This commit is sufficient for Cavium ThunderX2 (and maybe others) where there is one ITS block per NUMA node.

Test Plan

Boot up on Cavium ThunderX2

[andrew]

sys/dev/pci/pci_host_generic_acpi.c

314

This won't work as the errno values are positive. It might be better to set sc->xref in generic_pcie_acpi_get_domain, or to pass in a pointer to be set.

[jchandra]

sys/dev/pci/pci_host_generic_acpi.c

314

Will pass in a pointer - (forgot about this difference between FreeBSD and Linux).

Looking thru the code again, I think I forgot to call acpi_map_pxm_to_vm_domainid() too - although it does not make any difference now.

will fix both - thanks.

[jchandra]

sys/dev/pci/pci_host_generic_acpi.c

314

I think I forgot to call acpi_map_pxm_to_vm_domainid()

Please ignore this part. I had called it in generic_pcie_acpi_get_domain()

[jchandra]

I will keep this on hold until we do ACPI based NUMA correctly. x86/acpica/srat.c seems to do most of the things we require, along with memory proximity and SLIT parsing - that would be a better starting point.

[jchandra]

Need to take another look at this after handling IORT table parsing.