Commit Graph

43 Commits

Author SHA1 Message Date
Gavin Shan
3fa7bf7229 powerpc/eeh: Don't remove passed VFs
When we have partial hotplug as part of the error recovery on PF,
the VFs that are bound with vfio-pci driver will experience hotplug.
That's not allowed.

This checks if the VF PE is passed or not. If it does, we leave
the VF without removing it.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-09 09:58:27 +11:00
Gavin Shan
2311cca555 powerpc/eeh: Don't propagate error to guest
When EEH error happened to the parent PE of those PEs that have
been passed through to guest, the error is propagated to guest
domain and the VFIO driver's error handlers are called. It's not
correct as the error in the host domain shouldn't be propagated
to guests and affect them.

This adds one more limitation when calling EEH error handlers.
If the PE has been passed through to guest, the error handlers
won't be called.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-09 09:58:25 +11:00
Wei Yang
67086e32b5 powerpc/eeh: powerpc/eeh: Support error recovery for VF PE
PFs are enumerated on PCI bus, while VFs are created by PF's driver.

In EEH recovery, it has two cases:
1. Device and driver is EEH aware, error handlers are called.
2. Device and driver is not EEH aware, un-plug the device and plug it again
by enumerating it.

The special thing happens on the second case. For a PF, we could use the
original pci core to enumerate the bus, while for VF we need to record the
VFs which aer un-plugged then plug it again.

Also The patch caches the VF index in pci_dn, which can be used to
calculate VF's bus, device and function number. Those information helps to
locate the VF's PCI device instance when doing hotplug during EEH recovery
if necessary.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-09 09:58:23 +11:00
Michael Ellerman
2527083cb8 powerpc fixes for 4.5 #3
- eeh: Fix partial hotplug criterion from Gavin Shan
  - mm: Clear the invalid slot information correctly from Aneesh Kumar K.V
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Merge tag 'powerpc-4.5-4' into next

Pull in our current fixes from 4.5, in particular the "Fix Multi hit
ERAT" bug is causing folks some grief when testing next.
2016-02-25 21:52:58 +11:00
Gavin Shan
f6bf0fa14c powerpc/eeh: Fix partial hotplug criterion
During error recovery, the device could be removed as part of the
partial hotplug. The criterion used to come with partial hotplug
is: if the device driver provides error_detected(), slot_reset()
and resume() callbacks, it's immune from hotplug. Otherwise,
it's going to experience partial hotplug during EEH recovery. But
the criterion isn't correct enough: mlx4_core driver for Mellanox
adapters provides error_detected(), slot_reset() callbacks, but
resume() isn't there. Those Mellanox adapters won't be to involved
in the partial hotplug.

This fixes the criterion to a practical one: adpater with driver
that provides error_detected(), slot_reset() will be immune from
partial hotplug. resume() isn't mandatory.

Fixes: f2da4ccf ("powerpc/eeh: More relaxed hotplug criterion")
Cc: stable@vger.kernel.org #v4.4+
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-22 19:25:55 +11:00
Gavin Shan
05ba75f848 powerpc/eeh: Fix stale cached primary bus
When PE is created, its primary bus is cached to pe->bus. At later
point, the cached primary bus is returned from eeh_pe_bus_get().
However, we could get stale cached primary bus and run into kernel
crash in one case: full hotplug as part of fenced PHB error recovery
releases all PCI busses under the PHB at unplugging time and recreate
them at plugging time. pe->bus is still dereferencing the PCI bus
that was released.

This adds another PE flag (EEH_PE_PRI_BUS) to represent the validity
of pe->bus. pe->bus is updated when its first child EEH device is
online and the flag is set. Before unplugging in full hotplug for
error recovery, the flag is cleared.

Fixes: 8cdb2833 ("powerpc/eeh: Trace PCI bus from PE")
Cc: stable@vger.kernel.org #v3.11+
Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reported-by: Pradipta Ghosh <pradghos@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-15 21:10:04 +11:00
Linus Torvalds
d43421565b PCI changes for the v4.5 merge window:
Enumeration
     Simplify config space size computation (Bjorn Helgaas)
     Avoid iterating through ROM outside the resource window (Edward O'Callaghan)
     Support PCIe devices with short cfg_size (Jason S. McMullan)
     Add Netronome vendor and device IDs (Jason S. McMullan)
     Limit config space size for Netronome NFP6000 family (Jason S. McMullan)
     Add Netronome NFP4000 PF device ID (Simon Horman)
     Limit config space size for Netronome NFP4000 (Simon Horman)
     Print warnings for all invalid expansion ROM headers (Vladis Dronov)
 
   Resource management
     Fix minimum allocation address overwrite (Christoph Biedl)
 
   PCI device hotplug
     acpiphp_ibm: Fix null dereferences on null ibm_slot (Colin Ian King)
     pciehp: Always protect pciehp_disable_slot() with hotplug mutex (Guenter Roeck)
     shpchp: Constify hpc_ops structure (Julia Lawall)
     ibmphp: Remove unneeded NULL test (Julia Lawall)
 
   Power management
     Make ASPM sysfs link_state_store() consistent with link_state_show() (Andy Lutomirski)
 
   Virtualization
     Add function 1 DMA alias quirk for Lite-On/Plextor M6e/Marvell 88SS9183 (Tim Sander)
 
   MSI
     Remove empty pci_msi_init_pci_dev() (Bjorn Helgaas)
     Mark PCIe/PCI (MSI) IRQ cascade handlers as IRQF_NO_THREAD (Grygorii Strashko)
     Initialize MSI capability for all architectures (Guilherme G. Piccoli)
     Relax msi_domain_alloc() to support parentless MSI irqdomains (Liu Jiang)
 
   ARM Versatile host bridge driver
     Remove unused pci_sys_data structures (Lorenzo Pieralisi)
 
   Broadcom iProc host bridge driver
     Hide CONFIG_PCIE_IPROC (Arnd Bergmann)
     Do not use 0x in front of %pap (Dmitry V. Krivenok)
     Update iProc PCIe device tree binding (Ray Jui)
     Add PAXC interface support (Ray Jui)
     Add iProc PCIe MSI device tree binding (Ray Jui)
     Add iProc PCIe MSI support (Ray Jui)
 
   Freescale i.MX6 host bridge driver
     Use gpio_set_value_cansleep() (Fabio Estevam)
     Add support for active-low reset GPIO (Petr Štetiar)
 
   HiSilicon host bridge driver
     Add support for HiSilicon Hip06 PCIe host controllers (Gabriele Paoloni)
 
   Intel VMD host bridge driver
     Export irq_domain_set_info() for module use (Keith Busch)
     x86/PCI: Allow DMA ops specific to a PCI domain (Keith Busch)
     Use 32 bit PCI domain numbers (Keith Busch)
     Add driver for Intel Volume Management Device (VMD) (Keith Busch)
 
   Qualcomm host bridge driver
     Document PCIe devicetree bindings (Stanimir Varbanov)
     Add Qualcomm PCIe controller driver (Stanimir Varbanov)
     dts: apq8064: add PCIe devicetree node (Stanimir Varbanov)
     dts: ifc6410: enable PCIe DT node for this board (Stanimir Varbanov)
 
   Renesas R-Car host bridge driver
     Add support for R-Car H3 to pcie-rcar (Harunobu Kurokawa)
     Allow DT to override default window settings (Phil Edworthy)
     Convert to DT resource parsing API (Phil Edworthy)
     Revert "PCI: rcar: Build pcie-rcar.c only on ARM" (Phil Edworthy)
     Remove unused pci_sys_data struct from pcie-rcar (Phil Edworthy)
     Add runtime PM support to pcie-rcar (Phil Edworthy)
     Add Gen2 PHY setup to pcie-rcar (Phil Edworthy)
     Add gen2 fallback compatibility string for pci-rcar-gen2 (Simon Horman)
     Add gen2 fallback compatibility string for pcie-rcar (Simon Horman)
 
   Synopsys DesignWare host bridge driver
     Simplify control flow (Bjorn Helgaas)
     Make config accessor override checking symmetric (Bjorn Helgaas)
     Ensure ATU is enabled before IO/conf space accesses (Stanimir Varbanov)
 
   Miscellaneous
     Add of_pci_get_host_bridge_resources() stub (Arnd Bergmann)
     Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask (Bjorn Helgaas)
     Fix all whitespace issues (Bogicevic Sasa)
     x86/PCI: Simplify pci_bios_{read,write} (Geliang Tang)
     Use to_pci_dev() instead of open-coding it (Geliang Tang)
     Use kobj_to_dev() instead of open-coding it (Geliang Tang)
     Use list_for_each_entry() to simplify code (Geliang Tang)
     Fix typos in <linux/msi.h> (Thomas Petazzoni)
     x86/PCI: Clarify AMD Fam10h config access restrictions comment (Tomasz Nowicki)
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Merge tag 'pci-v4.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v4.5 merge window:

  Enumeration:
   - Simplify config space size computation (Bjorn Helgaas)
   - Avoid iterating through ROM outside the resource window (Edward O'Callaghan)
   - Support PCIe devices with short cfg_size (Jason S. McMullan)
   - Add Netronome vendor and device IDs (Jason S. McMullan)
   - Limit config space size for Netronome NFP6000 family (Jason S. McMullan)
   - Add Netronome NFP4000 PF device ID (Simon Horman)
   - Limit config space size for Netronome NFP4000 (Simon Horman)
   - Print warnings for all invalid expansion ROM headers (Vladis Dronov)

  Resource management:
   - Fix minimum allocation address overwrite (Christoph Biedl)

  PCI device hotplug:
   - acpiphp_ibm: Fix null dereferences on null ibm_slot (Colin Ian King)
   - pciehp: Always protect pciehp_disable_slot() with hotplug mutex (Guenter Roeck)
   - shpchp: Constify hpc_ops structure (Julia Lawall)
   - ibmphp: Remove unneeded NULL test (Julia Lawall)

  Power management:
   - Make ASPM sysfs link_state_store() consistent with link_state_show() (Andy Lutomirski)

  Virtualization
   - Add function 1 DMA alias quirk for Lite-On/Plextor M6e/Marvell 88SS9183 (Tim Sander)

  MSI:
   - Remove empty pci_msi_init_pci_dev() (Bjorn Helgaas)
   - Mark PCIe/PCI (MSI) IRQ cascade handlers as IRQF_NO_THREAD (Grygorii Strashko)
   - Initialize MSI capability for all architectures (Guilherme G. Piccoli)
   - Relax msi_domain_alloc() to support parentless MSI irqdomains (Liu Jiang)

  ARM Versatile host bridge driver:
   - Remove unused pci_sys_data structures (Lorenzo Pieralisi)

  Broadcom iProc host bridge driver:
   - Hide CONFIG_PCIE_IPROC (Arnd Bergmann)
   - Do not use 0x in front of %pap (Dmitry V. Krivenok)
   - Update iProc PCIe device tree binding (Ray Jui)
   - Add PAXC interface support (Ray Jui)
   - Add iProc PCIe MSI device tree binding (Ray Jui)
   - Add iProc PCIe MSI support (Ray Jui)

  Freescale i.MX6 host bridge driver:
   - Use gpio_set_value_cansleep() (Fabio Estevam)
   - Add support for active-low reset GPIO (Petr Štetiar)

  HiSilicon host bridge driver:
   - Add support for HiSilicon Hip06 PCIe host controllers (Gabriele Paoloni)

  Intel VMD host bridge driver:
   - Export irq_domain_set_info() for module use (Keith Busch)
   - x86/PCI: Allow DMA ops specific to a PCI domain (Keith Busch)
   - Use 32 bit PCI domain numbers (Keith Busch)
   - Add driver for Intel Volume Management Device (VMD) (Keith Busch)

  Qualcomm host bridge driver:
   - Document PCIe devicetree bindings (Stanimir Varbanov)
   - Add Qualcomm PCIe controller driver (Stanimir Varbanov)
   - dts: apq8064: add PCIe devicetree node (Stanimir Varbanov)
   - dts: ifc6410: enable PCIe DT node for this board (Stanimir Varbanov)

  Renesas R-Car host bridge driver:
   - Add support for R-Car H3 to pcie-rcar (Harunobu Kurokawa)
   - Allow DT to override default window settings (Phil Edworthy)
   - Convert to DT resource parsing API (Phil Edworthy)
   - Revert "PCI: rcar: Build pcie-rcar.c only on ARM" (Phil Edworthy)
   - Remove unused pci_sys_data struct from pcie-rcar (Phil Edworthy)
   - Add runtime PM support to pcie-rcar (Phil Edworthy)
   - Add Gen2 PHY setup to pcie-rcar (Phil Edworthy)
   - Add gen2 fallback compatibility string for pci-rcar-gen2 (Simon Horman)
   - Add gen2 fallback compatibility string for pcie-rcar (Simon Horman)

  Synopsys DesignWare host bridge driver:
   - Simplify control flow (Bjorn Helgaas)
   - Make config accessor override checking symmetric (Bjorn Helgaas)
   - Ensure ATU is enabled before IO/conf space accesses (Stanimir Varbanov)

  Miscellaneous:
   - Add of_pci_get_host_bridge_resources() stub (Arnd Bergmann)
   - Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask (Bjorn Helgaas)
   - Fix all whitespace issues (Bogicevic Sasa)
   - x86/PCI: Simplify pci_bios_{read,write} (Geliang Tang)
   - Use to_pci_dev() instead of open-coding it (Geliang Tang)
   - Use kobj_to_dev() instead of open-coding it (Geliang Tang)
   - Use list_for_each_entry() to simplify code (Geliang Tang)
   - Fix typos in <linux/msi.h> (Thomas Petazzoni)
   - x86/PCI: Clarify AMD Fam10h config access restrictions comment (Tomasz Nowicki)"

* tag 'pci-v4.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (58 commits)
  PCI: Add function 1 DMA alias quirk for Lite-On/Plextor M6e/Marvell 88SS9183
  PCI: Limit config space size for Netronome NFP4000
  PCI: Add Netronome NFP4000 PF device ID
  x86/PCI: Add driver for Intel Volume Management Device (VMD)
  PCI/AER: Use 32 bit PCI domain numbers
  x86/PCI: Allow DMA ops specific to a PCI domain
  irqdomain: Export irq_domain_set_info() for module use
  PCI: host: Add of_pci_get_host_bridge_resources() stub
  genirq/MSI: Relax msi_domain_alloc() to support parentless MSI irqdomains
  PCI: rcar: Add Gen2 PHY setup to pcie-rcar
  PCI: rcar: Add runtime PM support to pcie-rcar
  PCI: designware: Make config accessor override checking symmetric
  PCI: ibmphp: Remove unneeded NULL test
  ARM: dts: ifc6410: enable PCIe DT node for this board
  ARM: dts: apq8064: add PCIe devicetree node
  PCI: hotplug: Use list_for_each_entry() to simplify code
  PCI: rcar: Remove unused pci_sys_data struct from pcie-rcar
  PCI: hisi: Add support for HiSilicon Hip06 PCIe host controllers
  PCI: Avoid iterating through memory outside the resource window
  PCI: acpiphp_ibm: Fix null dereferences on null ibm_slot
  ...
2016-01-21 11:52:16 -08:00
Bjorn Helgaas
93de690176 PCI: Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask
Bit 7 of the "Header Type" register indicates a multi-function device when
set.  Bits 0-6 contain encoded values, where 0x1 indicates a PCI-PCI
bridge.  It is incorrect to test this as though it were a mask.

For example, while the PCI 3.0 spec only defines values 0x0, 0x1, and 0x2,
it's conceivable that a future spec could define 0x3 to mean something
else; then tests for "(hdr_type & 0x7f) & PCI_HEADER_TYPE_BRIDGE" would
incorrectly succeed for this new 0x3 header type.

Test bits 0-6 of the Header Type for equality with PCI_HEADER_TYPE_BRIDGE.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-12-10 19:38:06 -06:00
Andrew Donnellan
dc9c41bd9e Revert "powerpc/eeh: Don't unfreeze PHB PE after reset"
This reverts commit 527d10ef3a.

The reverted commit breaks cxlflash devices following an EEH reset (and
possibly other cxl devices, however this has not been tested).

The reverted commit changed the behaviour of eeh_reset_device() so that PHB
PEs are not unfrozen following the completion of the reset. This should not
be problematic, as no device resources should have been associated with the
PHB PE.

However, when attempting to load the cxlflash driver after a reset, the
driver attempts to read Vital Product Data through a call to
pci_read_vpd() (which is called on the physical cxl device, not on the
virtual AFU device). pci_read_vpd() in turn attempts to read from the cxl
device's config space. This fails, as the PE it's trying to read from is
still frozen. In turn, the driver gets an -ENODEV and fails to initialise.

It appears this issue only affects some parts of the VPD area, as "lspci
-vvv", which only reads a subset of the VPD bytes, is not broken by the
original patch.

At this stage, we don't fully understand why we're trying to read a frozen
PE, and we don't know how this affects other cxl devices. It is possible
that there is an underlying bug in the cxl driver or the powerpc CAPI
support code, or alternatively a bug in the PCI resource allocation/mapping
code that is incorrectly mapping resources to PE#0.

As such, this fix is incomplete, however it is necessary to prevent a
serious regression in CAPI support.

In the meantime, revert the commit, especially as it was intended to be a
non-functional change.

Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Daniel Axtens <dja@axtens.net>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-09 14:05:10 +11:00
Gavin Shan
8234fcedf1 powerpc/eeh: Force reset on fenced PHB
On fenced PHB, the error handlers in the drivers of its subordinate
devices could return PCI_ERS_RESULT_CAN_RECOVER, indicating no reset
will be issued during the recovery. It's conflicting with the fact
that fenced PHB won't be recovered without reset.

This limits the return value from the error handlers in the drivers
of the fenced PHB's subordinate devices to PCI_ERS_RESULT_NEED_NONE
or PCI_ERS_RESULT_NEED_RESET, to ensure reset will be issued during
recovery.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-21 20:41:43 +11:00
Gavin Shan
f2da4ccf8b powerpc/eeh: More relaxed hotplug criterion
Currently, we rely on the existence of struct pci_driver::err_handler
to decide if the corresponding PCI device should be unplugged during
EEH recovery (partially hotplug case). However that check is not
sufficient. Some device drivers implement only some of the EEH error
handlers to collect diag-data. That means the driver still expects a
hotplug to recover from the EEH error.

This makes the hotplug criterion more relaxed: if the device driver
doesn't provide all necessary EEH error handlers, it will experience
hotplug during EEH recovery.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
[mpe: Minor change log rewording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-21 20:39:07 +11:00
Gavin Shan
527d10ef3a powerpc/eeh: Don't unfreeze PHB PE after reset
On PowerNV platform, the PE is kept in frozen state until the PE
reset is completed to avoid recursive EEH error caused by MMIO
access during the period of EEH reset. The PE's frozen state is
cleared after BARs of PCI device included in the PE are restored
and enabled. However, we needn't clear the frozen state for PHB PE
explicitly at this point as there is no real PE for PHB PE. As the
PHB PE is always binding with PE#0, we actually clear PE#0, which
is wrong. It doesn't incur any problem though.

This checks if the PE is PHB PE and doesn't clear the frozen state
if it is.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-21 20:06:57 +11:00
Wei Yang
2ac3990cc3 powerpc/eeh: fix comment for wait_state()
To retrieve the PCI slot state, EEH driver would set a timeout for that.
While current comment is not aligned to what the code does.

This patch fixes those comments according to the code.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-05-13 14:00:07 +10:00
Gavin Shan
c6406d8fbb powerpc/eeh: Remove device_node dependency
The patch removes struct eeh_dev::dn and the corresponding helper
functions: eeh_dev_to_of_node() and of_node_to_eeh_dev(). Instead,
eeh_dev_to_pdn() and pdn_to_eeh_dev() should be used to get the
pdn, which might contain device_node on PowerNV platform.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:53 +11:00
Gavin Shan
1b28f170d9 powerpc/eeh: Allow to set maximal frozen times
When PE's frozen count hits maximal allowed frozen times, which is
5 currently, it will be forced to be offline permanently. Once the
PE is removed permanently, rebooting machine is required to bring
the PE back. It's not convienent when testing EEH functionality.

The patch exports the maximal allowed frozen times through debugfs
entry (/sys/kernel/debug/powerpc/eeh_max_freezes).

Requested-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-01-23 14:02:54 +11:00
Gavin Shan
432227e907 powerpc/eeh: Introduce flag EEH_PE_REMOVED
The conditions that one specific PE's frozen count exceeds the maximal
allowed times (EEH_MAX_ALLOWED_FREEZES) and it's in isolated or recovery
state indicate the PE was removed permanently implicitly. The patch
introduces flag EEH_PE_REMOVED to indicate that explicitly so that we
don't depend on the fixed maximal allowed times, which can be varied as
we do in subsequent patch.

Flag EEH_PE_REMOVED is expected to be marked for the PE whose frozen
count exceeds the maximal allowed times, or just failed from recovery.

Requested-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-01-23 14:02:53 +11:00
Gavin Shan
28bf36f92a powerpc/eeh: Set EEH_PE_RESET on PE reset
The patch introduces additional flag EEH_PE_RESET to indicate the
corresponding PE is under reset. In turn, the PE retrieval bakcend
on PowerNV platform can return unfrozen state for the EEH core to
moving forward. Flag EEH_PE_CFG_BLOCKED isn't the correct one for
the purpose.

In PCI passthrou case, the problem is more worse: Guest doesn't
recover 6th EEH error. The PE is left in isolated (frozen) and
config blocked state on Broadcom adapters. We can't retrieve the
PE's state correctly any more, even from the host side via sysfs
/sys/bus/pci/devices/xxx/eeh_pe_state.

Reported-by: Rajeshkumar Subramanian <rajeshkumars@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-12-02 11:03:26 +11:00
Gavin Shan
8a6b3710cc powerpc/eeh: Rename flag EEH_PE_RESET to EEH_PE_CFG_BLOCKED
The flag EEH_PE_RESET indicates blocking config space of the PE
during reset time. We potentially need block PE's config space
other than reset time. So it's reasonable to replace it with
EEH_PE_CFG_BLOCKED to indicate its usage.

There are no substantial code or logic changes in this patch.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-10-15 11:27:18 +11:00
Gavin Shan
5cfb20b96f powerpc/eeh: Emulate EEH recovery for VFIO devices
When enabling EEH functionality on passed through devices (PE)
with VFIO, the devices in the PE would be removed permanently
from guest side. In that case, the PE remains frozen state.
When returning PE to host, or restarting the guest again, we
had mechanism unfreezing the PE by clearing PESTA/B frozen
bits. However, that's not enough for some adapters, which are
indicated as following "lspci" shows. Those adapters require
hot reset on the parent bus to bring their firmware back to
workable state. Otherwise, those adaptrs won't be operative
and the host (for returning case) or the guest will fail to
load the drivers for those adapters without exception.

0000:01:00.0 Ethernet controller: Emulex Corporation OneConnect \
             10Gb NIC (be3) (rev 02)
0000:01:00.0 0200: 19a2:0710 (rev 02)
0001:03:00.0 Ethernet controller: Emulex Corporation OneConnect \
             NIC (Lancer) (rev 10)
0001:03:00.0 0200: 10df:e220 (rev 10)

The patch adds mechanism to emulate EEH recovery (for hot reset
on parent PCI bus) on 3 gates to fix the issue: open/release one
adapter of the PE, enable EEH functionality on one adapter of the
PE.

Reported-by:  Murilo Fossa Vicentini <muvic@br.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:18 +10:00
Gavin Shan
c9dd014397 powerpc/eeh: Use eeh_unfreeze_pe()
The patch uses eeh_unfreeze_pe() to replace the logic clearing
frozen IO and DMA, in order to simplify the code.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-30 17:15:14 +10:00
Gavin Shan
0dae27439a powerpc/eeh: Replace pr_warning() with pr_warn()
pr_warn() is equal to pr_warning(), but the former is a bit more
formal according to commit fc62f2f ("kernel.h: add pr_warn for
symmetry to dev_warn, netdev_warn").

The patch replaces pr_warning() with pr_warn().

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 15:41:34 +10:00
Gavin Shan
5c7a35e3e2 powerpc/powernv: Fix killed EEH event
On PowerNV platform, EEH errors are reported by IO accessors or poller
driven by interrupt. After the PE is isolated, we won't produce EEH
event for the PE. The current implementation has possibility of EEH
event lost in this way:

The interrupt handler queues one "special" event, which drives the poller.
EEH thread doesn't pick the special event yet. IO accessors kicks in, the
frozen PE is marked as "isolated" and EEH event is queued to the list.
EEH thread runs because of special event and purge all existing EEH events.
However, we never produce an other EEH event for the frozen PE. Eventually,
the PE is marked as "isolated" and we don't have EEH event to recover it.

The patch fixes the issue to keep EEH events for PEs that have been
marked as "isolated" with the help of additional "force" help to
eeh_remove_event().

Reported-by: Rolf Brudeseth <rolfb@us.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 17:04:33 +10:00
Gavin Shan
2c66599206 powerpc/eeh: Clear frozen state for child PE
Since commit cb523e09 ("powerpc/eeh: Avoid I/O access during PE
reset"), the PE is kept as frozen state on hardware level until
the PE reset is done completely. After that, we explicitly clear
the frozen state of the affected PE. However, there might have
frozen child PEs of the affected PE and we also need clear their
frozen state as well. Otherwise, the recovery is going to fail.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 17:04:12 +10:00
Gavin Shan
35845a7826 powerpc/eeh: Can't recover from non-PE-reset case
When PCI_ERS_RESULT_CAN_RECOVER returned from device drivers, the
EEH core should enable I/O and DMA for the affected PE. However,
it was missed to have DMA enabled in eeh_handle_normal_event().
Besides, the frozen state of the affected PE should be cleared
after successful recovery, but we didn't.

The patch fixes both of the issues as above.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:35:01 +10:00
Gavin Shan
d2b0f6f77e powerpc/eeh: No hotplug on permanently removed dev
The issue was detected in a bit complicated test case where
we have multiple hierarchical PEs shown as following figure:

                +-----------------+
                | PE#3     p2p#0  |
                |          p2p#1  |
                +-----------------+
                        |
                +-----------------+
                | PE#4     pdev#0 |
                |          pdev#1 |
                +-----------------+

PE#4 (have 2 PCI devices) is the child of PE#3, which has 2 p2p
bridges. We accidentally had less-known scenario: PE#4 was removed
permanently from the system because of permanent failure (e.g.
exceeding the max allowd failure times in last hour), then we detects
EEH errors on PE#3 and tried to recover it. However, eeh_dev instances
for pdev#0/1 were not detached from PE#4, which was still connected to
PE#3. All of that was because of the fact that we rely on count-based
pcibios_release_device(), which isn't reliable enough. When doing
recovery for PE#3, we still apply hotplug on PE#4 and pdev#0/1, which
are not valid any more. Eventually, we run into kernel crash.

The patch fixes above issue from two aspects. For unplug, we simply
skip those permanently removed PE, whose state is (EEH_PE_STATE_ISOLATED
&& !EEH_PE_STATE_RECOVERING) and its frozen count should be greater
than EEH_MAX_ALLOWED_FREEZES. For plug, we marked all permanently
removed EEH devices with EEH_DEV_REMOVED and return 0xFF's on read
its PCI config so that PCI core will omit them.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:32 +10:00
Gavin Shan
7895470063 powerpc/eeh: Avoid I/O access during PE reset
We have suffered recrusive frozen PE a lot, which was caused
by IO accesses during the PE reset. Ben came up with the good
idea to keep frozen PE until recovery (BAR restore) gets done.
With that, IO accesses during PE reset are dropped by hardware
and wouldn't incur the recrusive frozen PE any more.

The patch implements the idea. We don't clear the frozen state
until PE reset is done completely. During the period, the EEH
core expects unfrozen state from backend to keep going. So we
have to reuse EEH_PE_RESET flag, which has been set during PE
reset, to return normal state from backend. The side effect is
we have to clear frozen state for towice (PE reset and clear it
explicitly), but that's harmless.

We have some limitations on pHyp. pHyp doesn't allow to enable
IO or DMA for unfrozen PE. So we don't enable them on unfrozen PE
in eeh_pci_enable(). We have to enable IO before grabbing logs on
pHyp. Otherwise, 0xFF's is always returned from PCI config space.
Also, we had wrong return value from eeh_pci_enable() for
EEH_OPT_THAW_DMA case. The patch fixes it too.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:10 +10:00
Gavin Shan
d0914f503f powerpc/eeh: Block PCI-CFG access during PE reset
We've observed multiple PE reset failures because of PCI-CFG
access during that period. Potentially, some device drivers
can't support EEH very well and they can't put the device to
motionless state before PE reset. So those device drivers might
produce PCI-CFG accesses during PE reset. Also, we could have
PCI-CFG access from user space (e.g. "lspci"). Since access to
frozen PE should return 0xFF's, we can block PCI-CFG access
during the period of PE reset so that we won't get recrusive EEH
errors.

The patch adds flag EEH_PE_RESET, which is kept during PE reset.
The PowerNV/pSeries PCI-CFG accessors reuse the flag to block
PCI-CFG accordingly.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:34:02 +10:00
Gavin Shan
9e04937560 powerpc/eeh: Remove EEH_PE_PHB_DEAD
The PE state (for eeh_pe instance) EEH_PE_PHB_DEAD is duplicate to
EEH_PE_ISOLATED. Originally, those PHBs (PHB PE) with EEH_PE_PHB_DEAD
would be removed from the system. However, it's safe to replace
that with EEH_PE_ISOLATED.

The patch also clear EEH_PE_RECOVERING after fenced PHB has been handled,
either failure or success. It makes the PHB PE state consistent with:

	PHB functions normally		  NONE
	PHB has been removed		  EEH_PE_ISOLATED
	PHB fenced, recovery in progress  EEH_PE_ISOLATED | RECOVERING

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28 17:33:39 +10:00
Thomas Gleixner
57310c3c99 powerpc: eeh: Fixup the brown paperbag fallout of the "cleanup"
Commit b8a9a11b9 (powerpc: eeh: Kill another abuse of irq_desc) is
missing some brackets .....

It's not a good idea to write patches in grumpy mode and then forget
to at least compile test them or rely on the few eyeballs discussing
that patch to spot it.....

Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
2014-03-05 00:13:33 +01:00
Thomas Gleixner
b8a9a11b97 powerpc: Eeh: Kill another abuse of irq_desc
commit 91150af3a (powerpc/eeh: Fix unbalanced enable for IRQ) is
another brilliant example of trainwreck engineering.

The patch "fixes" the issue of an unbalanced call to irq_enable()
which causes a prominent warning by checking the disabled state of the
interrupt line and call conditionally into the core code.

This is wrong in two aspects:

1) The warning is there to tell users, that they need to fix their
   asymetric enable/disable patterns by finding the root cause and
   solving it there.

   It's definitely not meant to work around it by conditionally
   calling into the core code depending on the random state of the irq
   line.

   Asymetric irq_disable/enable calls are a clear sign of wrong usage
   of the interfaces which have to be cured at the root and not by
   somehow hacking around it.

2) The abuse of core internal data structure instead of using the
   proper interfaces for retrieving the information for the 'hack
   around'

   irq_desc is core internal and it's clear enough stated.

Replace at least the irq_desc abuse with the proper functions and add
a big fat comment why this is absurd and completely wrong.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.562906212@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04 17:37:52 +01:00
Thadeu Lima de Souza Cascardo
8cc6b6cd87 powerpc/eeh: Drop taken reference to driver on eeh_rmv_device
Commit f5c57710dd ("powerpc/eeh: Use
partial hotplug for EEH unaware drivers") introduces eeh_rmv_device,
which may grab a reference to a driver, but not release it.

That prevents a driver from being removed after it has gone through EEH
recovery.

This patch drops the reference if it was taken.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-02-11 11:24:46 +11:00
Linus Torvalds
1b17366d69 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc updates from Ben Herrenschmidt:
 "So here's my next branch for powerpc.  A bit late as I was on vacation
  last week.  It's mostly the same stuff that was in next already, I
  just added two patches today which are the wiring up of lockref for
  powerpc, which for some reason fell through the cracks last time and
  is trivial.

  The highlights are, in addition to a bunch of bug fixes:

   - Reworked Machine Check handling on kernels running without a
     hypervisor (or acting as a hypervisor).  Provides hooks to handle
     some errors in real mode such as TLB errors, handle SLB errors,
     etc...

   - Support for retrieving memory error information from the service
     processor on IBM servers running without a hypervisor and routing
     them to the memory poison infrastructure.

   - _PAGE_NUMA support on server processors

   - 32-bit BookE relocatable kernel support

   - FSL e6500 hardware tablewalk support

   - A bunch of new/revived board support

   - FSL e6500 deeper idle states and altivec powerdown support

  You'll notice a generic mm change here, it has been acked by the
  relevant authorities and is a pre-req for our _PAGE_NUMA support"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (121 commits)
  powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked()
  powerpc: Add support for the optimised lockref implementation
  powerpc/powernv: Call OPAL sync before kexec'ing
  powerpc/eeh: Escalate error on non-existing PE
  powerpc/eeh: Handle multiple EEH errors
  powerpc: Fix transactional FP/VMX/VSX unavailable handlers
  powerpc: Don't corrupt transactional state when using FP/VMX in kernel
  powerpc: Reclaim two unused thread_info flag bits
  powerpc: Fix races with irq_work
  Move precessing of MCE queued event out from syscall exit path.
  pseries/cpuidle: Remove redundant call to ppc64_runlatch_off() in cpu idle routines
  powerpc: Make add_system_ram_resources() __init
  powerpc: add SATA_MV to ppc64_defconfig
  powerpc/powernv: Increase candidate fw image size
  powerpc: Add debug checks to catch invalid cpu-to-node mappings
  powerpc: Fix the setup of CPU-to-Node mappings during CPU online
  powerpc/iommu: Don't detach device without IOMMU group
  powerpc/eeh: Hotplug improvement
  powerpc/eeh: Call opal_pci_reinit() on powernv for restoring config space
  powerpc/eeh: Add restore_config operation
  ...
2014-01-27 21:11:26 -08:00
Rafael J. Wysocki
1c2042c83a powerpc/eeh: Use global PCI rescan-remove locking
Race conditions are theoretically possible between the PCI device addition
and removal in the PPC64 PCI error recovery driver and the generic PCI bus
rescan and device removal that can be triggered via sysfs.

To avoid those race conditions make PPC64 PCI error recovery driver use
global PCI rescan-remove locking around PCI device addition and removal.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-15 10:31:29 -07:00
Gavin Shan
7e4e7867b1 powerpc/eeh: Handle multiple EEH errors
For one PCI error relevant OPAL event, we possibly have multiple
EEH errors for that. For example, multiple frozen PEs detected on
different PHBs. Unfortunately, we didn't cover the case. The patch
enumarates the return value from eeh_ops::next_error() and change
eeh_handle_special_event() and eeh_ops::next_error() to handle all
existing EEH errors.

As Ben pointed out, we needn't list_for_each_entry_safe() since we
are not deleting any PHB from the hose_list and the EEH serialized
lock should be held while purging EEH events. The patch covers those
suggestions as well.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15 17:18:58 +11:00
Gavin Shan
f26c7a035b powerpc/eeh: Hotplug improvement
When EEH error comes to one specific PCI device before its driver
is loaded, we will apply hotplug to recover the error. During the
plug time, the PCI device will be probed and its driver is loaded.
Then we wrongly calls to the error handlers if the driver supports
EEH explicitly.

The patch intends to fix by introducing flag EEH_DEV_NO_HANDLER and
set it before we remove the PCI device. In turn, we can avoid wrongly
calls the error handlers of the PCI device after its driver loaded.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15 13:58:29 +11:00
Brian King
fb48dc2282 powerpc: Increase EEH recovery timeout for SR-IOV
In order to support concurrent adapter firmware download
to SR-IOV adapters on pSeries, each VF will see an EEH event
where the slot will remain in the unavailable state for
the duration of the adapter firmware update, which can take
as long as 5 minutes. Extend the EEH recovery timeout to
account for this.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-05 16:08:20 +11:00
Gavin Shan
91150af3ad powerpc/eeh: Fix unbalanced enable for IRQ
The patch fixes following issue:

Unbalanced enable for IRQ 23
------------[ cut here ]------------
WARNING: at kernel/irq/manage.c:437
:
NIP [c00000000016de8c] .__enable_irq+0x11c/0x140
LR [c00000000016de88] .__enable_irq+0x118/0x140
Call Trace:
[c000003ea1f23880] [c00000000016de88] .__enable_irq+0x118/0x140 (unreliable)
[c000003ea1f23910] [c00000000016df08] .enable_irq+0x58/0xa0
[c000003ea1f239a0] [c0000000000388b4] .eeh_enable_irq+0xc4/0xe0
[c000003ea1f23a30] [c000000000038a28] .eeh_report_reset+0x78/0x130
[c000003ea1f23ac0] [c000000000037508] .eeh_pe_dev_traverse+0x98/0x170
[c000003ea1f23b60] [c0000000000391ac] .eeh_handle_normal_event+0x2fc/0x3d0
[c000003ea1f23bf0] [c000000000039538] .eeh_handle_event+0x2b8/0x2c0
[c000003ea1f23c90] [c000000000039600] .eeh_event_handler+0xc0/0x170
[c000003ea1f23d30] [c0000000000da9a0] .kthread+0xf0/0x100
[c000003ea1f23e30] [c00000000000a1dc] .ret_from_kernel_thread+0x5c/0x80

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:49 +10:00
Gavin Shan
f5c57710dd powerpc/eeh: Use partial hotplug for EEH unaware drivers
When EEH error happens to one specific PE, some devices with drivers
supporting EEH won't except hotplug on the device. However, there
might have other deivces without driver, or with driver without EEH
support. For the case, we need do partial hotplug in order to make
sure that the PE becomes absolutely quite during reset. Otherise,
the PE reset might fail and leads to failure of error recovery.

The current code doesn't handle that 'mixed' case properly, it either
uses the error callbacks to the drivers, or tries hotplug, but doesn't
handle a PE (EEH domain) composed of a combination of the two.

The patch intends to support so-called "partial" hotplug for EEH:
Before we do reset, we stop and remove those PCI devices without
EEH sensitive driver. The corresponding EEH devices are not detached
from its PE, but with special flag. After the reset is done, those
EEH devices with the special flag will be scanned one by one.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:48 +10:00
Gavin Shan
807a827d4e powerpc/eeh: Keep PE during hotplug
When we do normal hotplug, the PE (shadow EEH structure) shouldn't be
kept around.

However, we need to keep it if the hotplug an artifial one caused by
EEH errors recovery.

Since we remove EEH device through the PCI hook pcibios_release_device(),
the flag "purge_pe" passed to various functions is meaningless. So the patch
removes the meaningless flag and introduce new flag "EEH_PE_KEEP"
to save the PE while doing hotplug during EEH error recovery.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24 14:18:47 +10:00
Gavin Shan
56ca4fde90 powerpc/eeh: Refactor the output message
We needn't the the whole backtrace other than one-line message in
the error reporting interrupt handler. For errors triggered by
access PCI config space or MMIO, we replace "WARN(1, ...)" with
pr_err() and dump_stack(). The patch also adds more output messages
to indicate what EEH core is doing. Besides, some printk() are
replaced with pr_warning().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01 11:10:33 +10:00
Gavin Shan
8a6b1bc70d powerpc/eeh: EEH core to handle special event
On PowerNV platform, the EEH event caused by interrupt won't have
binding PE. The patch enables EEH core to handle the special event.
To avoid the current logic we have, The eeh_handle_event() is renamed
to eeh_handle_normal_event(), and the eeh_handle_special_event() is
introduced. The function eeh_handle_event() dispatches to above two
functions according to the input parameter. Besides, new backend
"next_error" added to eeh_ops and it's expected to have following
return values:

        4 - Dead IOC           3 - Dead PHB
        2 - Fenced PHB         1 - Frozen PE
        0 - No error found

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:06:14 +10:00
Gavin Shan
5a71978e4b powerpc/eeh: Trace time on first error for PE
We're not expecting that one specific PE got frozen for over 5
times in last hour. Otherwise, the PE will be removed from the
system upon newly coming EEH errors. The patch introduces time
stamp to trace the first error on specific PE in last hour and
function to update that accordingly. Besides, the time stamp
is recovered during PE hotplug path as we did for frozen count.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:06:04 +10:00
Gavin Shan
317f06de78 powerpc/eeh: Move common part to kernel directory
The patch moves the common part of EEH core into arch/powerpc/kernel
directory so that we needn't PPC_PSERIES while compiling POWERNV
platform:

        * Move the EEH common part into arch/powerpc/kernel
        * Move the functions for PCI hotplug from pSeries platform to
          arch/powerpc/kernel/pci-hotplug.c
        * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to
          arch/powerpc/platforms/Kconfig
        * Adjust makefile accordingly

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 17:05:35 +10:00