On Sat, Mar 2, 2019 at 3:04 AM Sergey Miroshnichenko
wrote:
>
> This patchset allows switching from the pnv_php module to the standard
> pciehp driver for PCIe hotplug functionality, if the platform supports it:
> PowerNV working on on top of the skiboot with the "core/pci: Sync VFs and
> the changes of bdfns between the firmware and the OS" patch serie applied.
>
> The feature is activated by the "pci=realloc" command line argument.
>
> The goal is ability to hotplug bridges full of devices in the future. The
> "Movable BARs" [1] is a platform-independent part of our work in this. The
> final part will be movable bus numbers to support inserting a bridge in the
> middle of an existing PCIe tree.
>
> Tested on POWER8 PowerNV+PHB3 ppc64le (our Vesnin server) with:
> - the pciehp driver active;
> - the pnv_php driver disabled;
Cool :)
I've had a brief look at this and it the approach seems reasonable.
I'll have a more detailed look and see how it fares on a P9 system
tomorrow.
> - The "pci=realloc" argument is passed;
> - surprise hotplug of an NVME disk works;
> - controlled hotplug of a network card with SR-IOV works;
> - activating of SR-IOV on a network card works;
> - [with extra patches] manually initiated (via sysfs) rescan has found
>and turned on a hotplugged bridge;
> - Without "pci=realloc" works just as before.
>
> Changes since v3 [2]:
> - Subject changed;
> - Don't disable EEH during rescan anymore - instead just unfreeze the
>target buses deliberately;
> - Add synchronization with the firmware when changing the PCIe topology;
> - Fixed for VFs;
> - Code cleanup.
>
> Changes since v2:
> - Don't reassign bus numbers on PowerNV by default (to retain the default
>behavior), but only when pci=realloc is passed;
> - Less code affected;
> - pci_add_device_node_info is refactored with add_one_dev_pci_data;
> - Minor code cleanup.
>
> Changes since v1:
> - Fixed build for ppc64le and ppc64be when CONFIG_PCI_IOV is disabled;
> - Fixed build for ppc64e when CONFIG_EEH is disabled;
> - Fixed code style warnings.
>
> [1] https://www.spinics.net/lists/linux-pci/msg79995.html
> [2] https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-September/178053.html
>
> Sergey Miroshnichenko (9):
> powerpc/pci: Access PCI config space directly w/o pci_dn
> powerpc/powernv/pci: Suppress an EEH error when reading an empty slot
> powerpc/pci: Create pci_dn on demand
> powerpc/pci: Reduce code duplication in pci_add_device_node_info
> powerpc/powernv/ioda: Fix using uninitialized IOMMU group
> powerpc/pci/IOV: Add support for runtime enabling the VFs
> powerpc/pci: Don't rely on DT is the PCI_REASSIGN_ALL_BUS is set
> powerpc/powernv/pci: Hook up the writes to PCI_SECONDARY_BUS register
> powerpc/powernv/pci: Enable reassigning the bus numbers
>
> arch/powerpc/include/asm/pci-bridge.h| 2 +-
> arch/powerpc/include/asm/ppc-pci.h | 1 +
> arch/powerpc/kernel/pci_dn.c | 164 +++
> arch/powerpc/kernel/rtas_pci.c | 97 ++---
> arch/powerpc/platforms/powernv/eeh-powernv.c | 2 +-
> arch/powerpc/platforms/powernv/pci-ioda.c| 5 +-
> arch/powerpc/platforms/powernv/pci.c | 208 +--
> arch/powerpc/platforms/pseries/pci.c | 2 +-
> 8 files changed, 381 insertions(+), 100 deletions(-)
>
> --
> 2.20.1
>
