On Sat, May 09, 2015 at 09:59:25AM +1000, Alexey Kardashevskiy wrote:
>On 05/01/2015 04:02 PM, Gavin Shan wrote:
>>The series of patches intend to support PCI slot for PowerPC PowerNV platform,
>>which is running on top of skiboot firmware. The patchset requires corresponding
>>changes from skiboot firmware, which is sent to skiboot@xxxxxxxxxxxxxxxx
>>for review. The PCI slots are exposed by skiboot with device node properties,
>>and kernel utilizes those properties to populated PCI slots accordingly.
>>
>>The original PCI infrastructure on PowerNV platform can't support hotplug
>>because the PE is assigned during PHB fixup time, which is called for once
>>during system boot time. For this, the PCI infrastructure on PowerNV platform
>>has been reworked for a lot. After that, the PE and its corresponding resources
>>(IODT, M32DT, M64 segments, DMA32 and bypass window) are assigned upon updating
>>PCI bridge's resources, which might decide PE# assigned to the PE (e.g. M64
>>resources, on P8 strictly speaking).
>
>Out of curiosity - does this PCI scan happen when memory subsystem is
>initialized? More precisely, after these changes, won't
>pnv_pci_ioda2_setup_dma_pe() be called too early after boot so I won't be
>able to use kmalloc() to allocate iommu_table's?
>
PCI scan (enumeration) is invoked quite late during system bootup time by
subsys_initcall(). When it's called, the slab should have been initialized.
>Also, checkpatch.pl failed multiple times on the series. Please fix.
>
Thanks for pointing it out, I'll fix them one by one.
>>Each PE will maintain a reference count,
>>which is (number of child PCI devices + 1). That indicates when last child PCI
>>device leaves the PE, the PE and its included resources will be relased and put
>>back into free pool again. With this design, the PE will be released when EEH PE
>>is released. PATCH[1 - 8] are related to this part.
>>
>> From skiboot perspective, PCI slot is providing (hot/fundamental/complete)
>>resets to EEH. The kernel gets to know if skiboot supports various reset on one
>>particular PCI slot through device-tree node. If it does, EEH will utilize the
>>functionality provided by skiboot. Besides, the device-tree nodes have to change
>>in order to support PCI hotplug. For example, when one PCI adapter inserted to
>>one slot, its device-tree node should be added to the system dynamically. Conversely,
>>the device-tree node should be removed from the system when the PCI adapter is going
>>to be offline. Since pci_dn and eeh_dev have same life cyle as PCI device nodes,
>>they should be added/removed accordingly during PCI hotplug. Patch[9 - 20] are
>>doing the related work.
>>
>>The last patch is the standalone PCI hotplug driver for PowerNV platform. When
>>removing PCI adapter from one PCI slot, which is invoked by command in userland,
>>the skiboot will power off the slot to save power and remove all device-tree
>>nodes for all PCI devices behind the slot. Conversely, the Power to the slot
>>is turned on, the PCI devices behind the slot is rescanned, and the device-tree
>>nodes for those newly detected PCI devices will be built in skiboot. For both
>>of cases, one message will be sent to kernel by skiboot so that the kernel
>>can adjust the device-tree accordingly. At the same time, the kernel also have
>>to deallocate or allocate PE# and its related resources (PE# and so on) for the
>>removed/added PCI devices.
>>
>>Changelog
>>=========
>>v4:
>> * Rebased to 4.1.RC1
>> * Added API to unflatten FDT blob to device node sub-tree, which is attached
>> the indicated parent device node. The original mechanism based on formatted
>> string stream has been dropped.
>> * The PATCH[v3 09/21] ("powerpc/eeh: Delay probing EEH device during hotplug")
>> was picked up sent to linux-ppc@ separately for review as Richard's "VF EEH
>> Support" depends on that.
>>v3:
>> * Rebased to 4.1.RC0
>> * PowerNV PCI infrasturcture is total refactored in order to support PCI
>> hotplug. The PowerNV hotplug driver is also reworked a lot because of
>> the changes in skiboot in order to support PCI hotplug.
>>
>>Gavin Shan (21):
>> pci: Add pcibios_setup_bridge()
>> powerpc/powernv: Enable M64 on P7IOC
>> powerpc/powernv: M64 support improvement
>> powerpc/powernv: Improve IO and M32 mapping
>> powerpc/powernv: Improve DMA32 segment assignment
>> powerpc/powernv: Create PEs dynamically
>> powerpc/powernv: Release PEs dynamically
>> powerpc/powernv: Drop pnv_ioda_setup_dev_PE()
>> powerpc/powernv: Use PCI slot reset infrastructure
>> powerpc/powernv: Fundamental reset for PCI bus reset
>> powerpc/pci: Don't scan empty slot
>> powerpc/pci: Move pcibios_find_pci_bus() around
>> powerpc/powernv: Introduce pnv_pci_poll()
>> powerpc/powernv: Functions to get/reset PCI slot status
>> powerpc/pci: Delay creating pci_dn
>> powerpc/pci: Create eeh_dev while creating pci_dn
>> powerpc/pci: Export traverse_pci_device_nodes()
>> powerpc/pci: Update bridge windows on PCI plugging
>> drivers/of: Support adding sub-tree
>> powerpc/powernv: Select OF_DYNAMIC
>> pci/hotplug: PowerPC PowerNV PCI hotplug driver
>>
>> arch/powerpc/include/asm/eeh.h | 7 +-
>> arch/powerpc/include/asm/opal-api.h | 7 +-
>> arch/powerpc/include/asm/opal.h | 7 +-
>> arch/powerpc/include/asm/pci-bridge.h | 7 +-
>> arch/powerpc/include/asm/pnv-pci.h | 5 +
>> arch/powerpc/include/asm/ppc-pci.h | 7 +-
>> arch/powerpc/kernel/eeh_dev.c | 20 +-
>> arch/powerpc/kernel/pci-common.c | 18 +-
>> arch/powerpc/kernel/pci-hotplug.c | 44 +-
>> arch/powerpc/kernel/pci_dn.c | 119 +-
>> arch/powerpc/platforms/maple/pci.c | 35 +-
>> arch/powerpc/platforms/pasemi/pci.c | 3 -
>> arch/powerpc/platforms/powermac/pci.c | 39 +-
>> arch/powerpc/platforms/powernv/Kconfig | 1 +
>> arch/powerpc/platforms/powernv/eeh-powernv.c | 245 ++--
>> arch/powerpc/platforms/powernv/opal-wrappers.S | 3 +
>> arch/powerpc/platforms/powernv/pci-ioda.c | 1657 +++++++++++++++---------
>> arch/powerpc/platforms/powernv/pci.c | 64 +-
>> arch/powerpc/platforms/powernv/pci.h | 52 +-
>> arch/powerpc/platforms/pseries/msi.c | 4 +-
>> arch/powerpc/platforms/pseries/pci_dlpar.c | 32 -
>> arch/powerpc/platforms/pseries/setup.c | 9 +-
>> drivers/of/dynamic.c | 19 +-
>> drivers/of/fdt.c | 133 +-
>> drivers/pci/hotplug/Kconfig | 12 +
>> drivers/pci/hotplug/Makefile | 4 +
>> drivers/pci/hotplug/powernv_php.c | 146 +++
>> drivers/pci/hotplug/powernv_php.h | 78 ++
>> drivers/pci/hotplug/powernv_php_slot.c | 643 +++++++++
>> drivers/pci/setup-bus.c | 12 +-
>> include/linux/of.h | 2 +
>> include/linux/of_fdt.h | 1 +
>> include/linux/pci.h | 1 +
>> 33 files changed, 2473 insertions(+), 963 deletions(-)
>> create mode 100644 drivers/pci/hotplug/powernv_php.c
>> create mode 100644 drivers/pci/hotplug/powernv_php.h
>> create mode 100644 drivers/pci/hotplug/powernv_php_slot.c
>>
Thanks,
Gavin
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
