diff options
Diffstat (limited to 'docs/system')
| -rw-r--r-- | docs/system/devices/cxl.rst | 18 | ||||
| -rw-r--r-- | docs/system/index.rst | 1 | ||||
| -rw-r--r-- | docs/system/sriov.rst | 37 |
3 files changed, 47 insertions, 9 deletions
diff --git a/docs/system/devices/cxl.rst b/docs/system/devices/cxl.rst index 882b036f5e..e307caf3f8 100644 --- a/docs/system/devices/cxl.rst +++ b/docs/system/devices/cxl.rst @@ -308,7 +308,7 @@ A very simple setup with just one directly attached CXL Type 3 Persistent Memory -object memory-backend-file,id=cxl-lsa1,share=on,mem-path=/tmp/lsa.raw,size=256M \ -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \ -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \ - -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \ + -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0,sn=0x1 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G A very simple setup with just one directly attached CXL Type 3 Volatile Memory device:: @@ -349,13 +349,13 @@ the CXL Type3 device directly attached (no switches).:: -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \ -device pxb-cxl,bus_nr=222,bus=pcie.0,id=cxl.2 \ -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \ - -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \ + -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0,sn=0x1 \ -device cxl-rp,port=1,bus=cxl.1,id=root_port14,chassis=0,slot=3 \ - -device cxl-type3,bus=root_port14,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem1 \ + -device cxl-type3,bus=root_port14,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem1,sn=0x2 \ -device cxl-rp,port=0,bus=cxl.2,id=root_port15,chassis=0,slot=5 \ - -device cxl-type3,bus=root_port15,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem2 \ + -device cxl-type3,bus=root_port15,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem2,sn=0x3 \ -device cxl-rp,port=1,bus=cxl.2,id=root_port16,chassis=0,slot=6 \ - -device cxl-type3,bus=root_port16,persistent-memdev=cxl-mem4,lsa=cxl-lsa4,id=cxl-pmem3 \ + -device cxl-type3,bus=root_port16,persistent-memdev=cxl-mem4,lsa=cxl-lsa4,id=cxl-pmem3,sn=0x4 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.targets.1=cxl.2,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=8k An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: @@ -375,13 +375,13 @@ An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: -device cxl-rp,port=1,bus=cxl.1,id=root_port1,chassis=0,slot=1 \ -device cxl-upstream,bus=root_port0,id=us0 \ -device cxl-downstream,port=0,bus=us0,id=swport0,chassis=0,slot=4 \ - -device cxl-type3,bus=swport0,persistent-memdev=cxl-mem0,lsa=cxl-lsa0,id=cxl-pmem0 \ + -device cxl-type3,bus=swport0,persistent-memdev=cxl-mem0,lsa=cxl-lsa0,id=cxl-pmem0,sn=0x1 \ -device cxl-downstream,port=1,bus=us0,id=swport1,chassis=0,slot=5 \ - -device cxl-type3,bus=swport1,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem1 \ + -device cxl-type3,bus=swport1,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem1,sn=0x2 \ -device cxl-downstream,port=2,bus=us0,id=swport2,chassis=0,slot=6 \ - -device cxl-type3,bus=swport2,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem2 \ + -device cxl-type3,bus=swport2,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem2,sn=0x3 \ -device cxl-downstream,port=3,bus=us0,id=swport3,chassis=0,slot=7 \ - -device cxl-type3,bus=swport3,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem3 \ + -device cxl-type3,bus=swport3,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem3,sn=0x4 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=4k Deprecations diff --git a/docs/system/index.rst b/docs/system/index.rst index c21065e519..718e9d3c56 100644 --- a/docs/system/index.rst +++ b/docs/system/index.rst @@ -39,3 +39,4 @@ or Hypervisor.Framework. multi-process confidential-guest-support vm-templating + sriov diff --git a/docs/system/sriov.rst b/docs/system/sriov.rst new file mode 100644 index 0000000000..d12178f3c3 --- /dev/null +++ b/docs/system/sriov.rst @@ -0,0 +1,37 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +Compsable SR-IOV device +======================= + +SR-IOV (Single Root I/O Virtualization) is an optional extended capability of a +PCI Express device. It allows a single physical function (PF) to appear as +multiple virtual functions (VFs) for the main purpose of eliminating software +overhead in I/O from virtual machines. + +There are devices with predefined SR-IOV configurations, but it is also possible +to compose an SR-IOV device yourself. Composing an SR-IOV device is currently +only supported by virtio-net-pci. + +Users can configure an SR-IOV-capable virtio-net device by adding +virtio-net-pci functions to a bus. Below is a command line example: + +.. code-block:: shell + + -netdev user,id=n -netdev user,id=o + -netdev user,id=p -netdev user,id=q + -device pcie-root-port,id=b + -device virtio-net-pci,bus=b,addr=0x0.0x3,netdev=q,sriov-pf=f + -device virtio-net-pci,bus=b,addr=0x0.0x2,netdev=p,sriov-pf=f + -device virtio-net-pci,bus=b,addr=0x0.0x1,netdev=o,sriov-pf=f + -device virtio-net-pci,bus=b,addr=0x0.0x0,netdev=n,id=f + +The VFs specify the paired PF with ``sriov-pf`` property. The PF must be +added after all VFs. It is the user's responsibility to ensure that VFs have +function numbers larger than one of the PF, and that the function numbers +have a consistent stride. Both the PF and VFs are ARI-capable so you can have +255 VFs at maximum. + +You may also need to perform additional steps to activate the SR-IOV feature on +your guest. For Linux, refer to [1]_. + +.. [1] https://docs.kernel.org/PCI/pci-iov-howto.html |