PCI address assignment

[Neil Duffy]

Hi,

I'm just testing my intel i350-T4, which I was hoping to use and pass through individual ports to VM's and my current motherboard only allows me to plug the card into the pci-e x16 slot (the rest are x1).

Anyway's, card works, all good... apart from the PCI assignment puts it into 0000:01:00:x, but loads of other system devices (including the CPU and its chipset) are in the 0000:01:xx group.

Is this a restriction due to the crappy H61 chipset on the motherboard I'm using?

I do have a replacement board with more capable pci-e slots, so hoping it won't be an issue then.

Am I right in thinking the motherboard and its bios force the pci addressing schema?

Thanks

Neil

 

[wolfgang]

Hi

Am I right in thinking the motherboard and its bios force the pci addressing schema?

Correct the mmuio groups are generated by the bios/uefi.
Sometimes an other bios version helps.

 

[Neil Duffy]

Hi,

Sorry, looks as if I was reading the lspci / iommu group assignment...

IOMMU Group 1 00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port [8086:0101] (rev 09)
IOMMU Group 1 01:00.0 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)
IOMMU Group 1 01:00.1 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)
IOMMU Group 1 01:00.2 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)
IOMMU Group 1 01:00.3 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)

However, looking at this, it appears as i'd have problems pass through individual ports, something I thought the i350-t4 was good for?

I don't 'have' to use the SR-IOV mode do I?

Thanks

Neil

 

[wolfgang]

However, looking at this, it appears as i'd have problems pass through individual ports, something I thought the i350-t4 was good for?

I think your iommu groups are not correct implemented.

normal it looks like this way. For every port one group.

IOMMU Group 25 03:00.0 Ethernet controller [0200]: Intel Corporation Ethernet Connection X552/X557-AT 10GBASE-T [8086:15ad]
IOMMU Group 26 03:00.1 Ethernet controller [0200]: Intel Corporation Ethernet Connection X552/X557-AT 10GBASE-T [8086:15ad]
IOMMU Group 27 05:00.0 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)
IOMMU Group 28 05:00.1 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01)

I don't 'have' to use the SR-IOV mode do I?

I would give it a try as an alternative.

 

[Neil Duffy]

What governs how iommu groups are assigned?

 

[wolfgang]

The bios firmware create this groups.