Re: [PATCH V7 00/17] Enable SRIOV on POWER8

[Wei Yang <weiyang@linux.vnet.ibm.com>]

On Tue, Aug 19, 2014 at 10:12:27PM -0500, Bjorn Helgaas wrote:
>On Tue, Aug 19, 2014 at 9:34 PM, Wei Yang <weiyang@linux.vnet.ibm.com> wrote:
>> On Tue, Aug 19, 2014 at 03:19:42PM -0600, Bjorn Helgaas wrote:
>>>On Thu, Jul 24, 2014 at 02:22:10PM +0800, Wei Yang wrote:
>>>> This patch set enables the SRIOV on POWER8.
>>>>
>>>> The gerneral idea is put each VF into one individual PE and allocate required
>>>> resources like DMA/MSI.
>>>>
>>>> One thing special for VF PE is we use M64BT to cover the IOV BAR. M64BT is one
>>>> hardware on POWER platform to map MMIO address to PE. By using M64BT, we could
>>>> map one individual VF to a VF PE, which introduce more flexiblity to users.
>>>>
>>>> To achieve this effect, we need to do some hack on pci devices's resources.
>>>> 1. Expand the IOV BAR properly.
>>>>    Done by pnv_pci_ioda_fixup_iov_resources().
>>>> 2. Shift the IOV BAR properly.
>>>>    Done by pnv_pci_vf_resource_shift().
>>>> 3. IOV BAR alignment is the total size instead of an individual size on
>>>>    powernv platform.
>>>>    Done by pnv_pcibios_sriov_resource_alignment().
>>>> 4. Take the IOV BAR alignment into consideration in the sizing and assigning.
>>>>    This is achieved by commit: "PCI: Take additional IOV BAR alignment in
>>>>    sizing and assigning"
>>>>
>>>> Test Environment:
>>>>        The SRIOV device tested is Emulex Lancer and Mellanox ConnectX-3 on
>>>>        POWER8.
>>>>
>>>> Examples on pass through a VF to guest through vfio:
>>>>      1. install necessary modules
>>>>         modprobe vfio
>>>>         modprobe vfio-pci
>>>>      2. retrieve the iommu_group the device belongs to
>>>>         readlink /sys/bus/pci/devices/0000:06:0d.0/iommu_group
>>>>         ../../../../kernel/iommu_groups/26
>>>>         This means it belongs to group 26
>>>>      3. see how many devices under this iommu_group
>>>>         ls /sys/kernel/iommu_groups/26/devices/
>>>>      4. unbind the original driver and bind to vfio-pci driver
>>>>         echo 0000:06:0d.0 > /sys/bus/pci/devices/0000:06:0d.0/driver/unbind
>>>>         echo  1102 0002 > /sys/bus/pci/drivers/vfio-pci/new_id
>>>>         Note: this should be done for each device in the same iommu_group
>>>>      5. Start qemu and pass device through vfio
>>>>         /home/ywywyang/git/qemu-impreza/ppc64-softmmu/qemu-system-ppc64 \
>>>>                 -M pseries -m 2048 -enable-kvm -nographic \
>>>>                 -drive file=/home/ywywyang/kvm/fc19.img \
>>>>                 -monitor telnet:localhost:5435,server,nowait -boot cd \
>>>>                 -device "spapr-pci-vfio-host-bridge,id=CXGB3,iommu=26,index=6"
>>>>
>>>> Verify this is the exact VF response:
>>>>      1. ping from a machine in the same subnet(the broadcast domain)
>>>>      2. run arp -n on this machine
>>>>         9.115.251.20             ether   00:00:c9:df:ed:bf   C eth0
>>>>      3. ifconfig in the guest
>>>>         # ifconfig eth1
>>>>         eth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>>>              inet 9.115.251.20  netmask 255.255.255.0  broadcast 9.115.251.255
>>>>              inet6 fe80::200:c9ff:fedf:edbf  prefixlen 64  scopeid 0x20<link>
>>>>              ether 00:00:c9:df:ed:bf  txqueuelen 1000 (Ethernet)
>>>>              RX packets 175  bytes 13278 (12.9 KiB)
>>>>              RX errors 0  dropped 0  overruns 0  frame 0
>>>>              TX packets 58  bytes 9276 (9.0 KiB)
>>>>              TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
>>>>      4. They have the same MAC address
>>>>
>>>>      Note: make sure you shutdown other network interfaces in guest.
>>>>
>>>> ---
>>>> v6 -> v7:
>>>>    1. add IORESOURCE_ARCH flag for IOV BAR on powernv platform.
>>>>    2. when IOV BAR has IORESOURCE_ARCH flag, the size is retrieved from
>>>>       hardware directly. If not, calculate as usual.
>>>>    3. reorder the patch set, group them by subsystem:
>>>>       PCI, powerpc, powernv
>>>>    4. rebase it on 3.16-rc6
>>>
>>>This doesn't apply for me on v3.16-rc6:
>>>
>>>  02:48:57 ~/linux$ stg rebase v3.16-rc6
>>>  Checking for changes in the working directory ... done
>>>  Rebasing to "v3.16-rc6" ... done
>>>  No patches applied
>>>  02:49:14 ~/linux$ stg import -M --sign m/wy
>>>  Checking for changes in the working directory ... done
>>>  Importing patch "pci-iov-export-interface-for" ... done
>>>  Importing patch "pci-iov-get-vf-bar-size-from" ... done
>>>  Importing patch "pci-add-weak" ... done
>>>  Importing patch "pci-take-additional-iov-bar" ... done
>>>  Importing patch "powerpc-pci-don-t-unset-pci" ... done
>>>  Importing patch "powerpc-pci-define" ... done
>>>  Importing patch "powrepc-pci-refactor-pci_dn" ... done
>>>  Importing patch "powerpc-powernv-use-pci_dn-in" ... error: patch failed:
>>>  arch/powerpc/platforms/powernv/pci.c:376
>>>  error: arch/powerpc/platforms/powernv/pci.c: patch does not apply
>>>  stg import: Diff does not apply cleanly
>>>
>>>What am I missing?
>>>
>>>I assume you intend these all to go through my tree just to keep them all
>>>together.  The ideal rebase target for me would be v3.17-rc1.
>>
>> Ok, I will rebase it on v3.17-rc1 upstream. While I guess the conflict is due
>> to some patches from Gavin, which is not merged at that moment. I will make
>> sure it applies to v3.17-rc1.
>
>I tried applying them on v3.16-rc6 as well as on every change to
>arch/powerpc/platforms/powernv/pci.c between v3.16-rc6 and v3.17-rc1,
>and none applied cleanly.  Patches you post should be based on some
>upstream tag, not on something that includes unmerged patches.

Sorry about this, I will pay attention to this next time.

>
>Bjorn

-- 
Richard Yang
Help you, Help me