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752,035 commits

Author SHA1 Message Date
Bjorn Helgaas
f64c146410 Merge branch 'pci/hotplug'
- fix use-before-set error in ibmphp (Dan Carpenter)

  - fix pciehp timeouts caused by Command Completed errata (Bjorn Helgaas)

  - fix refcounting in pnv_php hotplug (Julia Lawall)

  - clear pciehp Presence Detect and Data Link Layer Status Changed on
    resume so we don't miss hotplug events (Mika Westerberg)

  - only request pciehp control if we support it, so platform can use ACPI
    hotplug otherwise (Mika Westerberg)

  - convert SHPC to be builtin only (Mika Westerberg)

  - request SHPC control via _OSC if we support it (Mika Westerberg)

  - simplify SHPC handoff from firmware (Mika Westerberg)

* pci/hotplug:
  PCI: Improve "partially hidden behind bridge" log message
  PCI: Improve pci_scan_bridge() and pci_scan_bridge_extend() doc
  PCI: Move resource distribution for single bridge outside loop
  PCI: Account for all bridges on bus when distributing bus numbers
  ACPI / hotplug / PCI: Drop unnecessary parentheses
  ACPI / hotplug / PCI: Mark stale PCI devices disconnected
  ACPI / hotplug / PCI: Don't scan bridges managed by native hotplug
  PCI: hotplug: Add hotplug_is_native()
  PCI: shpchp: Add shpchp_is_native()
  PCI: shpchp: Fix AMD POGO identification
  PCI: shpchp: Use dev_printk() for OSHP-related messages
  PCI: shpchp: Remove get_hp_hw_control_from_firmware() wrapper
  PCI: shpchp: Remove acpi_get_hp_hw_control_from_firmware() flags
  PCI: shpchp: Rely on previous _OSC results
  PCI: shpchp: Request SHPC control via _OSC when adding host bridge
  PCI: shpchp: Convert SHPC to be builtin only
  PCI: pciehp: Make pciehp_is_native() stricter
  PCI: pciehp: Rename host->native_hotplug to host->native_pcie_hotplug
  PCI: pciehp: Request control of native hotplug only if supported
  PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
  PCI: pnv_php: Add missing of_node_put()
  PCI: pciehp: Add quirk for Command Completed errata
  PCI: Add Qualcomm vendor ID
  PCI: ibmphp: Fix use-before-set in get_max_bus_speed()

# Conflicts:
#	drivers/acpi/pci_root.c
2018-06-06 16:10:10 -05:00
Bjorn Helgaas
5e3165d1a8 Merge branch 'pci/enumeration'
- neaten pci=earlydump output (Andy Shevchenko)

  - avoid errors when extended config space inaccessible (Gilles Buloz)

  - prevent sysfs disable of device while driver attached (Christoph
    Hellwig)

  - use core interface to report PCIe link properties in bnx2x, bnxt_en,
    cxgb4, ixgbe (Bjorn Helgaas)

  - remove unused pcie_get_minimum_link() (Bjorn Helgaas)

* pci/enumeration:
  PCI: Remove unused pcie_get_minimum_link()
  ixgbe: Report PCIe link properties with pcie_print_link_status()
  cxgb4: Report PCIe link properties with pcie_print_link_status()
  bnxt_en: Report PCIe link properties with pcie_print_link_status()
  bnx2x: Report PCIe link properties with pcie_print_link_status()
  PCI: Prevent sysfs disable of device while driver is attached
  PCI: Check whether bridges allow access to extended config space
  x86/PCI: Make pci=earlydump output neat
2018-06-06 16:10:08 -05:00
Bjorn Helgaas
8e069da28d Merge branch 'pci/dpc'
- clear interrupt status in top half to avoid interrupt storm (Oza
    Pawandeep)

* pci/dpc:
  PCI/DPC: Clear interrupt status in interrupt handler top half
2018-06-06 16:10:06 -05:00
Bjorn Helgaas
08b5b2f783 Merge branch 'pci/aspm'
- disable ASPM L1.2 substate if we don't have LTR (Bjorn Helgaas)

  - respect platform ownership of LTR (Bjorn Helgaas)

* pci/aspm:
  PCI/ACPI: Request LTR control from platform before using it
  PCI/ASPM: Disable ASPM L1.2 Substate if we don't have LTR
2018-06-06 16:10:05 -05:00
Bjorn Helgaas
d7e02c08a9 Merge branch 'pci/aer'
- unify AER decoding for native and ACPI CPER sources (Alexandru Gagniuc)

  - add TLP header info to AER tracepoint (Thomas Tai)

  - add generic pcie_wait_for_link() interface (Oza Pawandeep)

  - handle AER ERR_FATAL by removing and re-enumerating devices, as
    Downstream Port Containment does (Oza Pawandeep)

  - factor out common code between AER and DPC recovery (Oza Pawandeep)

  - stop triggering DPC for ERR_NONFATAL errors (Oza Pawandeep)

  - share ERR_FATAL recovery path between AER and DPC (Oza Pawandeep)

* pci/aer:
  PCI/AER: Replace struct pcie_device with pci_dev
  PCI/AER: Remove unused parameters
  PCI/AER: Decode Error Source Requester ID
  PCI/AER: Remove aer_recover_work_func() forward declaration
  PCI/DPC: Use the generic pcie_do_fatal_recovery() path
  PCI/AER: Pass service type to pcie_do_fatal_recovery()
  PCI/DPC: Disable ERR_NONFATAL handling by DPC
  PCI/portdrv: Add generic pcie_port_find_device()
  PCI/portdrv: Add generic pcie_port_find_service()
  PCI/AER: Factor out error reporting to drivers/pci/pcie/err.c
  PCI/AER: Rename error recovery interfaces to generic PCI naming
  PCI/AER: Handle ERR_FATAL with removal and re-enumeration of devices
  PCI: Add generic pcie_wait_for_link() interface
  PCI/AER: Add TLP header information to tracepoint
  PCI/AER: Unify error bit printing for native and CPER reporting
2018-06-06 16:10:03 -05:00
Keith Busch
e13d17f732 PCI/AER: Replace struct pcie_device with pci_dev
The AER driver only needed the pcie_device to get to the port pci_dev.
Save the pci_dev pointer directly in struct aer_rpc and remove the
unnecessary indirection.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-05 17:08:52 -05:00
Keith Busch
8f6fb67775 PCI/AER: Remove unused parameters
Remove unused "struct pcie_device *" parameters to handle_error_source()
and aer_process_err_devices().  No functional change intended.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-05 17:08:52 -05:00
Mika Westerberg
e412d63d60 PCI: Improve "partially hidden behind bridge" log message
pci_scan_child_bus_extend() complains when we assign an unreachable
secondary bus number to a bridge.  For example, given the topology below:

  +-1b.0-[01-39]----00.0-[02-3a]--+-00.0-[03]----00.0
                                  +-01.0-[04-39]--
                                  \-02.0-[3a]----00.0

it logs the following messages:

  pci_bus 0000:3a: [bus 3a] partially hidden behind bridge 0000:02 [bus 02-39]
  pci_bus 0000:3a: [bus 3a] partially hidden behind bridge 0000:01 [bus 01-39]

These messages are incorrect (0000:02 is a bus, not a bridge) and
confusing.  Make the message more understandable:

  pci 0000:02:02.0: devices behind bridge are unusable because [bus 3a] cannot be assigned for them

Also, remove the reference to CardBus, because this issue affects all
varieties of PCI, not just CardBus.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
70f7880d2d PCI: Improve pci_scan_bridge() and pci_scan_bridge_extend() doc
It is not immediately clear what the two functions actually return so
add kernel-doc comment explaining it a bit better.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
14fe5951b6 PCI: Move resource distribution for single bridge outside loop
If there is only a single bridge on the bus, we assign all resources to it.
Currently this is done as a part of the resource distribution loop but it
does not have to be there, and moving it outside actually improves
readability because we can then save one indent level in the loop.

While there we can add hotplug_bridges == 1 && normal_bridges == 0 to
the same block because they are dealt the same way.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
3374c545c2 PCI: Account for all bridges on bus when distributing bus numbers
When distributing extra bus number space to hotplug bridges for future
extension, we don't account for the fact that there might be non-hotplug
bridges on the bus after the hotplug bridges.  For example:

  01:00.0 --+- 02:00.0 (HotPlug-) -- Thunderbolt host controller
            +- 02:01.0 (HotPlug+)
            \- 02:02.0 (HotPlug-) -- xHCI host controller

pci_scan_child_bus_extend() is supposed to distribute the remaining bus
numbers to the hotplug bridge at 02:01.0, but only after accounting for all
bridges on bus 02.  Since we don't check whether there's another
non-hotplug bridge after the hotplug bridge 02:01.0, it may not leave space
for the non-hotplug bridge:

  pci 0000:00:1b.0: PCI bridge to [bus 01-39]  (Root Port)
  pci 0000:01:00.0: PCI bridge to [bus 02-39]
  ...
  pci 0000:02:00.0: PCI bridge to [bus 03]
  pci 0000:02:01.0: PCI bridge to [bus 04]
  pci_bus 0000:04: [bus 04-39] extended by 0x35
  pci_bus 0000:04: bus scan returning with max=39
  pci_bus 0000:04: busn_res: [bus 04-39] end is updated to 39
  pci 0000:02:02.0: scanning [bus 00-00] behind bridge, pass 1
  pci_bus 0000:3a: scanning bus
  pci_bus 0000:3a: bus scan returning with max=3a
  pci_bus 0000:3a: busn_res: [bus 3a] end is updated to 3a
  pci_bus 0000:3a: [bus 3a] partially hidden behind bridge 0000:02 [bus 02-39]
  pci_bus 0000:3a: [bus 3a] partially hidden behind bridge 0000:01 [bus 01-39]
  pci_bus 0000:02: bus scan returning with max=3a
  pci_bus 0000:02: busn_res: [bus 02-39] end can not be updated to 3a

The resulting 'lspci -t' output looks like this:

  +-1b.0-[01-39]----00.0-[02-3a]--+-00.0-[03]----00.0
                             ^^   +-01.0-[04-39]--
                                  \-02.0-[3a]----00.0
                                          ^^
The xHCI host controller behind 02:02.0 is not usable because it would have
to be assigned bus 3a, which is not accessible through 00:1b.0.

To fix this, reserve at least one bus for each bridge while scanning
already configured bridges.  Then use this information in the second
scan to correct the available extra bus space for hotplug bridges.

After this change the 'lspci -t' output is what is expected:

  +-1b.0-[01-39]----00.0-[02-39]--+-00.0-[03]----00.0
                                  +-01.0-[04-38]--
                                  \-02.0-[39]----00.0

The xHCI controller is now on bus 39, where it is usable.

Fixes: 1c02ea8100 ("PCI: Distribute available buses to hotplug-capable bridges")
Reported-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org
2018-06-04 12:08:06 -05:00
Mika Westerberg
9337a49362 ACPI / hotplug / PCI: Drop unnecessary parentheses
Remove unnecessary parentheses.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
8f004f4a34 ACPI / hotplug / PCI: Mark stale PCI devices disconnected
Following PCIehp mark the unplugged PCI devices disconnected.  This makes
sure PCI core code leaves the now missing hardware registers alone.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
84c8b58ed3 ACPI / hotplug / PCI: Don't scan bridges managed by native hotplug
When acpiphp re-enumerates a PCI hierarchy because of an ACPI Notify()
event, we should skip bridges managed by native hotplug (pciehp or shpchp).
We don't want to scan below a native hotplug bridge until the hotplug
controller generates a hot-add event.

A typical scenario is a Root Port leading to a Thunderbolt host router that
remains powered off until something is connected to it.  See [1] for the
lspci details.

  1. Before something is connected, only the Root Port exists.  It has
     PCI_EXP_SLTCAP_HPC set and pciehp is responsible for hotplug:

       00:1b.0 Root Port (HotPlug+)

  2. When a USB-C or Thunderbolt device is connected, the Switch in the
     Thunderbolt host router is powered up, the Root Port signals a hotplug
     add event and pciehp enumerates the Switch:

       01:00.0 Switch Upstream Port   to [bus 02-39]
       02:00.0 Switch Downstream Port to [bus 03]    (HotPlug-, to NHI)
       02:01.0 Switch Downstream Port to [bus 04-38] (HotPlug+, to Thunderbolt connector)
       02:02.0 Switch Downstream Port to [bus 39]    (HotPlug-, to xHCI)

     The 02:00.0 and 02:02.0 Ports lead to Endpoints that are not powered
     up yet.  The Ports have PCI_EXP_SLTCAP_HPC cleared, so pciehp doesn't
     handle hotplug for them and we assign minimal resources to them.

     The 02:01.0 Port has PCI_EXP_SLTCAP_HPC set, so pciehp handles native
     hotplug events for it.

  3. The BIOS powers up the xHCI controller.  If a Thunderbolt device was
     connected (not just a USB-C device), it also powers up the NHI.  Then
     it sends an ACPI Notify() to the Root Port, and acpiphp enumerates the
     new device(s):

       03:00.0 Thunderbolt Host Controller (NHI) Endpoint
       39:00.0 xHCI Endpoint

  4. If a Thunderbolt device was connected, the host router firmware uses
     the NHI to set up Thunderbolt tunnels and triggers a native hotplug
     event (via 02:01.0 in this example).  Then pciehp enumerates the new
     Thunderbolt devices:

       04:00.0 Switch Upstream Port   to [bus 05-38]
       05:01.0 Switch Downstream Port to [bus 06-09] (HotPlug-)
       05:04.0 Switch Downstream Port to [bus 0a-38] (HotPlug+)

     In this example, 05:01.0 leads to another Switch and some NICs.  This
     subtree is static, so 05:01.0 doesn't support hotplug and has
     PCI_EXP_SLTCAP_HPC cleared.

In step 3, acpiphp previously enumerated everything below the Root Port,
including things below the 02:01.0 Port.  We don't want that because pciehp
expects to manage hotplug below that Port, and firmware on the host router
may be in the middle of configuring its Link so it may not be ready yet.

To make this work better with the native PCIe (pciehp) and standard PCI
(shpchp) hotplug drivers, we let them handle all slot management and
resource allocation for hotplug bridges and restrict ACPI hotplug to
non-hotplug bridges.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=199581#c5
Link: https://lkml.kernel.org/r/20180529160155.1738-1-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog, use hotplug_is_native() instead of
dev->is_hotplug_bridge]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
95d969ebb3 PCI: hotplug: Add hotplug_is_native()
Add hotplug_is_native() to find out whether the OS is supposed to handle
native hotplug of a given bridge.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Mika Westerberg
90cc0c3cc7 PCI: shpchp: Add shpchp_is_native()
In the same way we do for pciehp, add shpchp_is_native(), which returns
true if the bridge should be handled by the native SHPC driver.  Then
convert the driver to use this function.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-04 12:08:06 -05:00
Bjorn Helgaas
bed4e9cfab PCI: shpchp: Fix AMD POGO identification
The fix for an AMD POGO erratum related to SHPC incorrectly identified the
device.  The workaround should be applied only for AMD POGO devices, but it
was instead applied to:

  - all AMD bridges, and
  - all devices from any vendor with device ID 0x7458

Fixes: 53044f3574 ("[PATCH] PCI Hotplug: shpchp: AMD POGO errata fix")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-04 12:07:31 -05:00
Bjorn Helgaas
010caed4cc PCI/AER: Decode Error Source Requester ID
Decode the Requester ID from the AER Error Source Register into domain/
bus/device/function format to match other logging.  In cases where the ID
matches the device used for pci_err(), drop the extra ID completely so we
don't print it twice.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 19:29:29 -05:00
Borislav Petkov
ad4050dcda PCI/AER: Remove aer_recover_work_func() forward declaration
Just move the actual function up so that it is visible to its user
aer_recover_queue().

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 19:29:27 -05:00
Oza Pawandeep
b09803b5e5 PCI/DPC: Use the generic pcie_do_fatal_recovery() path
Our goal is to handle ERR_FATAL errors similarly, whether they are reported
via AER or via DPC.  A previous commit changed AER so it handles ERR_FATAL
by calling driver .remove() methods and resetting the Link.  DPC already
does that (although the Link reset is done automatically by hardware and
happens before we call the driver .remove() methods).

Restructure the DPC code so it calls the same pcie_do_fatal_recovery()
interface used by AER.  This makes it clearer that we want to use the same
path.

Implement the .reset_link() method used by pcie_do_fatal_recovery().  For
DPC, the actual reset is done automatically by hardware, so we really only
have to wait for the Link to be inactive, then release the Port from DPC.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog, DPC_FATAL is not a bitfield, can be sequential]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 19:29:27 -05:00
Oza Pawandeep
0b91439d35 PCI/AER: Pass service type to pcie_do_fatal_recovery()
Pass the service type to pcie_do_fatal_recovery() instead of assuming AER.
We will make DPC also use pcie_do_fatal_recovery(), and it needs to do
things a little differently for AER and DPC.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 19:29:26 -05:00
Oza Pawandeep
6927868e7a PCI/DPC: Disable ERR_NONFATAL handling by DPC
PCIe ERR_NONFATAL errors mean a particular transaction is unreliable but
the Link is otherwise fully functional (PCIe r4.0, sec 6.2.2).

The AER driver handles these by logging the error details and calling
driver-supplied pci_error_handlers callbacks.  It does not reset downstream
devices, does not remove them from the PCI subsystem, does not re-enumerate
them, and does not call their driver .remove() or .probe() methods.

But DPC driver previously enabled DPC on ERR_NONFATAL, so if the hardware
supports DPC, these errors caused a Link reset (performed automatically by
the hardware), followed by the DPC driver removing affected devices (which
calls their .remove() methods), bringing the Link back up, and
re-enumerating (which calls driver .probe() methods).

Disable ERR_NONFATAL DPC triggering so these errors will only be handled by
AER.  This means drivers won't have to deal with different usage of their
pci_error_handlers callbacks and .probe() and .remove() methods based on
whether the platform has DPC support.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 19:29:25 -05:00
Oza Pawandeep
e76d596aef PCI/portdrv: Add generic pcie_port_find_device()
Add generic pcie_port_find_device() routine.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-06-02 19:29:24 -05:00
Bjorn Helgaas
f2b775f5df PCI: shpchp: Use dev_printk() for OSHP-related messages
Use dev_printk() for messages related to requesting control of SHPC hotplug
via the OSHP method.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
96a621e01a PCI: shpchp: Remove get_hp_hw_control_from_firmware() wrapper
get_hp_hw_control_from_firmware() is a trivial wrapper around
acpi_get_hp_hw_control_from_firmware(), probably intended to be generic in
case other firmware needed similar OS/platform negotiation.

Remove get_hp_hw_control_from_firmware() and call
acpi_get_hp_hw_control_from_firmware() directly.  Add a stub for
acpi_get_hp_hw_control_from_firmware() for the non-ACPI case.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
6f77fa4941 PCI: shpchp: Remove acpi_get_hp_hw_control_from_firmware() flags
acpi_get_hp_hw_control_from_firmware() no longer uses the flags parameter,
so remove it.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
aa6be07c27 PCI: shpchp: Rely on previous _OSC results
If _OSC exists, we evaluated it when adding the ACPI host bridge, and we
requested SHPC control if the SHPC driver is present.  Use the result of
that _OSC evaluation instead of evaluating it again.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
1df81a6d6e PCI: shpchp: Request SHPC control via _OSC when adding host bridge
The SHPC driver now must be builtin (it cannot be a module).  If it is
present, request SHPC control immediately when adding the ACPI host bridge.
This is similar to how we handle native PCIe hotplug via pciehp.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
82280f7af7 PCI: shpchp: Convert SHPC to be builtin only
We need to be able coordinate between SHPC and acpiphp to determine which
driver handles hotplug of a given bridge.  Because acpiphp is already bool,
convert SHPC to be bool as well.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
5352a44a56 PCI: pciehp: Make pciehp_is_native() stricter
Previously pciehp_is_native() returned true for any PCI device in a
hierarchy where _OSC says we can use pciehp.  This is incorrect because
bridges without PCI_EXP_SLTCAP_HPC capability should be managed by acpiphp
instead.

Improve pciehp_is_native() to return true only when PCI_EXP_SLTCAP_HPC is
set and the pciehp driver is present.  In any other case return false
to let acpiphp handle those.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: remove NULL pointer check]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-02 00:18:28 -05:00
Mika Westerberg
9310f0dc1c PCI: pciehp: Rename host->native_hotplug to host->native_pcie_hotplug
Rename host->native_hotplug to host->native_pcie_hotplug to make room for a
similar flag for SHPC hotplug.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-06-02 00:18:28 -05:00
Bjorn Helgaas
e5b1db0186 PCI: Remove unused pcie_get_minimum_link()
In some cases pcie_get_minimum_link() returned misleading information
because it found the slowest link and the narrowest link without
considering the total bandwidth of the link.

For example, consider a path with these two links:

  - 16.0 GT/s  x1 link  (16.0 * 10^9 * 128 / 130) *  1 / 8 = 1969 MB/s
  -  2.5 GT/s x16 link  ( 2.5 * 10^9 *   8 /  10) * 16 / 8 = 4000 MB/s

The available bandwidth of the path is limited by the 16 GT/s link to about
1969 MB/s, but pcie_get_minimum_link() returned 2.5 GT/s x1, which
corresponds to only 250 MB/s.

Callers should use pcie_print_link_status() instead, or
pcie_bandwidth_available() if they need more detailed information.

Remove pcie_get_minimum_link() since there are no callers left.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-25 17:29:49 -05:00
Bjorn Helgaas
4695ca9d17 ixgbe: Report PCIe link properties with pcie_print_link_status()
Previously the driver used pcie_get_minimum_link() to warn when the NIC
is in a slot that can't supply as much bandwidth as the NIC could use.

pcie_get_minimum_link() can be misleading because it finds the slowest link
and the narrowest link (which may be different links) without considering
the total bandwidth of each link.  For a path with a 16 GT/s x1 link and a
2.5 GT/s x16 link, it returns 2.5 GT/s x1, which corresponds to 250 MB/s of
bandwidth, not the true available bandwidth of about 1969 MB/s for a
16 GT/s x1 link.

Use pcie_print_link_status() to report PCIe link speed and possible
limitations instead of implementing this in the driver itself.  This finds
the slowest link in the path to the device by computing the total bandwidth
of each link and compares that with the capabilities of the device.

The dmesg change is:

  - PCI Express bandwidth of %dGT/s available
  - (Speed:%s, Width: x%d, Encoding Loss:%s)
  + %u.%03u Gb/s available PCIe bandwidth (%s x%d link)

or, if the device is capable of better performance than is available in the
current slot:

  - This is not sufficient for optimal performance of this card.
  - For optimal performance, at least %dGT/s of bandwidth is required.
  - A slot with more lanes and/or higher speed is suggested.
  + %u.%03u Gb/s available PCIe bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)

Note that the driver previously used dev_warn() to suggest using a
different slot, but pcie_print_link_status() uses dev_info() because if the
platform has no faster slot available, the user can't do anything about the
warning and may not want to be bothered with it.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2018-05-25 17:29:49 -05:00
Bjorn Helgaas
57d12fc6f7 cxgb4: Report PCIe link properties with pcie_print_link_status()
Previously the driver used pcie_get_minimum_link() to warn when the NIC
is in a slot that can't supply as much bandwidth as the NIC could use.

pcie_get_minimum_link() can be misleading because it finds the slowest link
and the narrowest link (which may be different links) without considering
the total bandwidth of each link.  For a path with a 16 GT/s x1 link and a
2.5 GT/s x16 link, it returns 2.5 GT/s x1, which corresponds to 250 MB/s of
bandwidth, not the true available bandwidth of about 1969 MB/s for a
16 GT/s x1 link.

Use pcie_print_link_status() to report PCIe link speed and possible
limitations instead of implementing this in the driver itself.  This finds
the slowest link in the path to the device by computing the total bandwidth
of each link and compares that with the capabilities of the device.

The dmesg change is:

  - PCIe link speed is %s, device supports %s
  - PCIe link width is x%d, device supports x%d
  + %u.%03u Gb/s available PCIe bandwidth (%s x%d link)

or, if the device is capable of better performance than is available in the
current slot:

  - A slot with more lanes and/or higher speed is suggested for optimal performance.
  + %u.%03u Gb/s available PCIe bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-25 17:29:49 -05:00
Bjorn Helgaas
af125b754e bnxt_en: Report PCIe link properties with pcie_print_link_status()
Previously the driver used pcie_get_minimum_link() to warn when the NIC
is in a slot that can't supply as much bandwidth as the NIC could use.

pcie_get_minimum_link() can be misleading because it finds the slowest link
and the narrowest link (which may be different links) without considering
the total bandwidth of each link.  For a path with a 16 GT/s x1 link and a
2.5 GT/s x16 link, it returns 2.5 GT/s x1, which corresponds to 250 MB/s of
bandwidth, not the true available bandwidth of about 1969 MB/s for a
16 GT/s x1 link.

Use pcie_print_link_status() to report PCIe link speed and possible
limitations instead of implementing this in the driver itself.  This finds
the slowest link in the path to the device by computing the total bandwidth
of each link and compares that with the capabilities of the device.

The dmesg change is:

  - PCIe: Speed %s Width x%d
  + %u.%03u Gb/s available PCIe bandwidth (%s x%d link)

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-25 17:29:49 -05:00
Bjorn Helgaas
cc04a1dd3f bnx2x: Report PCIe link properties with pcie_print_link_status()
Previously the driver used pcie_get_minimum_link() to warn when the NIC
is in a slot that can't supply as much bandwidth as the NIC could use.

pcie_get_minimum_link() can be misleading because it finds the slowest link
and the narrowest link (which may be different links) without considering
the total bandwidth of each link.  For a path with a 16 GT/s x1 link and a
2.5 GT/s x16 link, it returns 2.5 GT/s x1, which corresponds to 250 MB/s of
bandwidth, not the true available bandwidth of about 1969 MB/s for a
16 GT/s x1 link.

Use pcie_print_link_status() to report PCIe link speed and possible
limitations instead of implementing this in the driver itself.  This finds
the slowest link in the path to the device by computing the total bandwidth
of each link and compares that with the capabilities of the device.

The dmesg change is:

  - %s (%c%d) PCI-E x%d %s found at mem %lx, IRQ %d, node addr %pM
  + %s (%c%d) PCI-E found at mem %lx, IRQ %d, node addr %pM
  + %u.%03u Gb/s available PCIe bandwidth (%s x%d link)

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-25 17:29:49 -05:00
Christoph Hellwig
6f5cdfa802 PCI: Prevent sysfs disable of device while driver is attached
Manipulating the enable_cnt behind the back of the driver will wreak
complete havoc with the kernel state, so disallow it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Keith Busch <keith.busch@intel.com>
2018-05-25 17:28:02 -05:00
Mika Westerberg
408fec36a1 PCI: pciehp: Request control of native hotplug only if supported
Currently we request control of native PCIe hotplug unconditionally.
Native PCIe hotplug events are handled by the pciehp driver, and if it is
not enabled those events will be lost.

Request control of native PCIe hotplug only if the pciehp driver is
enabled, so we will actually handle native PCIe hotplug events.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-23 17:42:53 -05:00
Mika Westerberg
13c65840fe PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
After a suspend/resume cycle the Presence Detect or Data Link Layer Status
Changed bits might be set.  If we don't clear them those events will not
fire anymore and nothing happens for instance when a device is now
hot-unplugged.

Fix this by clearing those bits in a newly introduced function
pcie_reenable_notification().  This should be fine because immediately
after, we check if the adapter is still present by reading directly from
the status register.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org
2018-05-23 17:42:53 -05:00
Julia Lawall
5d9c6b8ae9 PCI: pnv_php: Add missing of_node_put()
The device node iterators perform an of_node_get() on each iteration, so a
jump out of the loop requires an of_node_put().

The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
+  of_node_put(child);
?  break;
   ...
}
... when != child
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-23 16:48:37 -05:00
Oza Pawandeep
f252d0621a PCI/portdrv: Add generic pcie_port_find_service()
Add generic pcie_port_find_service() routine.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-05-17 16:49:30 -05:00
Oza Pawandeep
2e28bc84cf PCI/AER: Factor out error reporting to drivers/pci/pcie/err.c
Move the error reporting callbacks from aerdrv_core.c to err.c, where they
can be used by DPC in addition to AER.

As part of aerdrv_core.c, these callbacks were built under CONFIG_PCIEAER.
Moving them to the new err.c means they will now be built under
CONFIG_PCIEPORTBUS, so adjust the definition of pci_uevent_ers() to match.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: in reset_link(), initialize "driver" even if CONFIG_PCIEAER is
unset, update pci_uevent_ers() #ifdef wrapper]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-17 16:48:23 -05:00
Oza Pawandeep
d25e28e8d2 PCI/AER: Rename error recovery interfaces to generic PCI naming
Rename error recovery interfaces with "pcie_" prefix so they can be made
non-static.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: move declaration to later patch, leave functions static]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-05-17 16:48:15 -05:00
Oza Pawandeep
7e9084b367 PCI/AER: Handle ERR_FATAL with removal and re-enumeration of devices
PCIe ERR_FATAL errors mean the Link is unreliable.  Components on the Link
may need to be reset to return to reliable operation (PCIe r4.0, sec
6.2.2).  We previously handled these errors much differently depending on
whether the platform supports Downstream Port Containment (DPC) (PCIe r4.0,
sec 6.2.10) or not.

The AER driver has historically logged the error details, called
driver-supplied pci_error_handlers callbacks, and reset the Link.  This
reset downstream devices, but did not remove them from the PCI subsystem,
re-enumerate them, or call their driver .remove() or .probe() methods.

DPC is different because the hardware automatically disables the Link when
it detects ERR_FATAL, which resets downstream devices.  There's no
opportunity for pci_error_handlers callbacks before resetting the Link.
The DPC driver removes affected devices (which calls their driver .remove()
methods), brings the Link back up, and re-enumerates (which calls driver
.probe() methods).

Align AER ERR_FATAL handling with DPC by resetting the Link in software,
skipping the driver pci_error_handlers callbacks, removing the devices from
the PCI subsystem, and re-enumerating.  The idea is that drivers and
devices should see the same behavior for ERR_FATAL events, regardless of
whether they're handled by AER or DPC.

Here are the basic ERR_FATAL recovery steps, showing the previous AER
behavior, the AER behavior after this patch, and the DPC behavior:

                          AER        AER      DPC
                          previous   new      behavior
                          --------   ---      --------
  Log error               yes        yes      yes (minimal)
  drv.error_detected()    yes        no       no
  Reset Link              yes        yes      yes
  drv.mmio_enabled()      yes        no       no
  drv.slot_reset()        yes        no       no
  drv.resume()            yes        no       no
  Remove PCI devices      no         yes      yes
    (calls drv.remove())
  Re-enumerate            no         yes      yes
    (calls drv.probe())

N.B. With DPC, the Link reset happens before the driver .remove() calls,
while with AER, the reset happens *after* the .remove() calls.  The goal is
to eventually do the reset before .remove() for AER as well.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog, squash doc patch into this, remove unused
"result_data"]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-05-17 16:44:13 -05:00
Oza Pawandeep
9f5a70f18c PCI: Add generic pcie_wait_for_link() interface
Clients such as hotplug and Downstream Port Containment (DPC) both need to
wait until a link becomes active or inactive.

Add a generic pcie_wait_link_active() interface and use it instead of
duplicating the code.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-05-17 16:44:11 -05:00
Oza Pawandeep
56abbf8ad7 PCI/DPC: Clear interrupt status in interrupt handler top half
The generic IRQ handling code ensures that an interrupt handler runs with
its interrupt masked or disabled.  If the interrupt is level-triggered, the
interrupt handler must tell its device to stop asserting the interrupt
before returning.  If it doesn't, we will immediately take the interrupt
again when the handler returns and the generic code unmasks the interrupt.

The driver doesn't know whether its interrupt is edge- or level-triggered,
so it must clear its interrupt source directly in its interrupt handler.

Previously we cleared the DPC interrupt status in the bottom half, i.e., in
deferred work, which can cause an interrupt storm if the DPC interrupt
happens to be level-triggered, e.g., if we're using INTx instead of MSI.

Clear the DPC interrupt status bit in the interrupt handler, not in the
deferred work.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2018-05-16 15:59:35 -05:00
Thomas Tai
2af8641b2a PCI/AER: Add TLP header information to tracepoint
When a PCIe AER error occurs, the TLP header information is printed in the
kernel message but it is missing from the tracepoint.  A userspace program
can use this information in the tracepoint to better analyze problems.

To enable the tracepoint:

  echo 1 > /sys/kernel/debug/tracing/events/ras/aer_event/enable

Example tracepoint output:

  $ cat /sys/kernel/debug/tracing/trace
  aer_event: 0000:01:00.0
  PCIe Bus Error: severity=Uncorrected, non-fatal, Completer Abort
  TLP Header={0x0,0x1,0x2,0x3}

Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-10 08:34:52 -05:00
Alexandru Gagniuc
5d0b401f4c PCI/AER: Unify error bit printing for native and CPER reporting
AER errors can be reported natively (Linux AER driver fields interrupts and
reads error state directly from hardware) or via the ACPI/APEI/GHES/CPER
path (platform firmware reads error state from hardware and sends it to
Linux via ACPI interfaces).

Previously the same error would produce different output depending on
whether it was reported natively or via ACPI.  The CPER path resulted in
hard-to-understand messages, without a prefix. Instead use
__aer_print_error() for both native AER and CPER to provide a more
consistent log format.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-07 17:07:21 -05:00
Gilles Buloz
17e8f0d4ce PCI: Check whether bridges allow access to extended config space
Even if a device supports extended config space, i.e., it is a PCI-X Mode 2
or a PCI Express device, the extended space may not be accessible if
there's a conventional PCI bus in the path to it.

We currently figure that out in pci_cfg_space_size() by reading the first
dword of extended config space.  On most platforms that returns ~0 data if
the space is inaccessible, but it may set error bits in PCI status
registers, and on some platforms it causes exceptions that we currently
don't recover from.

For example, a PCIe-to-conventional PCI bridge treats config transactions
with a non-zero Extended Register Address as an Unsupported Request on PCIe
and a received Master-Abort on the destination bus (see PCI Express to
PCI/PCI-X Bridge spec, r1.0, sec 4.1.3).

A sample case is a LS1043A CPU (NXP QorIQ Layerscape) platform with the
following bus topology:

  LS1043 PCIe Root Port
    -> PEX8112 PCIe-to-PCI bridge (doesn't support ext cfg on PCI side)
      -> PMC slot connector (for legacy PMC modules)

With a PMC module topology as follows:

  PMC connector
    -> PCI-to-PCIe bridge
      -> PCIe switch (4 ports)
        -> 4 PCIe devices (one on each port)

The PCIe devices on the PMC module support extended config space, but we
can't reach it because the PEX8112 can't generate accesses to the extended
space on its secondary bus.  Attempts to access it cause Unsupported
Request errors, which result in synchronous aborts on this platform.

To avoid these errors, check whether bridges are capable of generating
extended config space addresses on their secondary interfaces.  If they
can't, we restrict devices below the bridge to only the 256-byte
PCI-compatible config space.

Signed-off-by: Gilles Buloz <gilles.buloz@kontron.com>
[bhelgaas: changelog, rework patch so bus_flags testing is all in
pci_bridge_child_ext_cfg_accessible()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-07 16:54:35 -05:00
Bjorn Helgaas
d22b362184 PCI: pciehp: Add quirk for Command Completed errata
Several PCIe hotplug controllers have errata that mean they do not set the
Command Completed bit unless writes to the Slot Command register change
"Control" bits.  Command Completed is never set for writes that only change
software notification "Enable" bits.  This results in timeouts like this:

  pciehp 0000:00:1c.0:pcie004: Timeout on hotplug command 0x1038 (issued 65284 msec ago)

When this erratum is present, avoid these timeouts by marking commands
"completed" immediately unless they change the "Control" bits.

Here's the text of the Intel erratum CF118.  We assume this applies to all
Intel parts:

  CF118        PCIe Slot Status Register Command Completed bit not always
               updated on any configuration write to the Slot Control
               Register

  Problem:     For PCIe root ports (devices 0 - 10) supporting hot-plug,
               the Slot Status Register (offset AAh) Command Completed
               (bit[4]) status is updated under the following condition:
               IOH will set Command Completed bit after delivering the new
               commands written in the Slot Controller register (offset
               A8h) to VPP. The IOH detects new commands written in Slot
               Control register by checking the change of value for Power
               Controller Control (bit[10]), Power Indicator Control
               (bits[9:8]), Attention Indicator Control (bits[7:6]), or
               Electromechanical Interlock Control (bit[11]) fields. Any
               other configuration writes to the Slot Control register
               without changing the values of these fields will not cause
               Command Completed bit to be set.

               The PCIe Base Specification Revision 2.0 or later describes
               the “Slot Control Register” in section 7.8.10, as follows
               (Reference section 7.8.10, Slot Control Register, Offset
               18h). In hot-plug capable Downstream Ports, a write to the
               Slot Control register must cause a hot-plug command to be
               generated (see Section 6.7.3.2 for details on hot-plug
               commands). A write to the Slot Control register in a
               Downstream Port that is not hotplug capable must not cause a
               hot-plug command to be executed.

               The PCIe Spec intended that every write to the Slot Control
               Register is a command and expected a command complete status
               to abstract the VPP implementation specific nuances from the
               OS software. IOH PCIe Slot Control Register implementation
               is not fully conforming to the PCIe Specification in this
               respect.

  Implication: Software checking on the Command Completed status after
               writing to the Slot Control register may time out.

  Workaround:  Software can read the Slot Control register and compare the
               existing and new values to determine if it should check the
               Command Completed status after writing to the Slot Control
               register.

Per Sinan, the Qualcomm QDF2400 controller also does not set the Command
Completed bit unless writes to the Slot Command register change "Control"
bits.

Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e7-v2-spec-update.html
Link: https://lkml.kernel.org/r/8770820b-85a0-172b-7230-3a44524e6c9f@molgen.mpg.de
Reported-by: Paul Menzel <pmenzel+linux-pci@molgen.mpg.de>	# Lenovo X60
Tested-by: Paul Menzel <pmenzel+linux-pci@molgen.mpg.de>	# Lenovo X60
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>		# Qcom quirk
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2018-05-07 16:25:08 -05:00