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  1. 01 8月, 2018 1 次提交
    • H
      PCI: Fix is_added/is_busmaster race condition · 44bda4b7
      由 Hari Vyas 提交于 
      When a PCI device is detected, pdev->is_added is set to 1 and proc and
sysfs entries are created.

When the device is removed, pdev->is_added is checked for one and then
device is detached with clearing of proc and sys entries and at end,
pdev->is_added is set to 0.

is_added and is_busmaster are bit fields in pci_dev structure sharing same
memory location.

A strange issue was observed with multiple removal and rescan of a PCIe
NVMe device using sysfs commands where is_added flag was observed as zero
instead of one while removing device and proc,sys entries are not cleared.
This causes issue in later device addition with warning message
"proc_dir_entry" already registered.

Debugging revealed a race condition between the PCI core setting the
is_added bit in pci_bus_add_device() and the NVMe driver reset work-queue
setting the is_busmaster bit in pci_set_master().  As these fields are not
handled atomically, that clears the is_added bit.

Move the is_added bit to a separate private flag variable and use atomic
functions to set and retrieve the device addition state.  This avoids the
race because is_added no longer shares a memory location with is_busmaster.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200283Signed-off-by: NHari Vyas <hari.vyas@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NLukas Wunner <lukas@wunner.de>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
      44bda4b7
  3. 05 6月, 2018 3 次提交
    • M
      PCI: Improve "partially hidden behind bridge" log message · e412d63d
      由 Mika Westerberg 提交于 
      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: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      e412d63d
    • M
      PCI: Improve pci_scan_bridge() and pci_scan_bridge_extend() doc · 70f7880d
      由 Mika Westerberg 提交于 
      It is not immediately clear what the two functions actually return so
add kernel-doc comment explaining it a bit better.
Suggested-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
      70f7880d
    • M
      PCI: Account for all bridges on bus when distributing bus numbers · 3374c545
      由 Mika Westerberg 提交于 
      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: 1c02ea81 ("PCI: Distribute available buses to hotplug-capable bridges")
Reported-by: NMario Limonciello <mario.limonciello@dell.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org
      3374c545
  5. 02 6月, 2018 2 次提交
  7. 31 5月, 2018 1 次提交
  9. 08 5月, 2018 1 次提交
    • G
      PCI: Check whether bridges allow access to extended config space · 17e8f0d4
      由 Gilles Buloz 提交于 
      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: NGilles 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: NBjorn Helgaas <bhelgaas@google.com>
      17e8f0d4
  11. 23 4月, 2018 1 次提交
    • B
      PCI/ACPI: Request LTR control from platform before using it · af8bb9f8
      由 Bjorn Helgaas 提交于 
      Per the PCI Firmware spec r3.2, sec 4.5, an ACPI-based OS should use _OSC
to request control of Latency Tolerance Reporting (LTR) before using it.

Request control of LTR, and if the platform does not grant control, don't
use it.

N.B. If the hardware supports LTR and the ASPM L1.2 substate but the BIOS
doesn't support LTR in _OSC, we previously would enable ASPM L1.2.  This
patch will prevent us from enabling ASPM L1.2 in that case.  It does not
prevent us from enabling PCI-PM L1.2, since that doesn't depend on LTR.
See PCIe r40, sec 5.5.1, for the L1 PM substate entry conditions.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      af8bb9f8
  13. 01 4月, 2018 1 次提交
  15. 31 3月, 2018 1 次提交
    • B
      PCI/portdrv: Simplify PCIe feature permission checking · 02bfeb48
      由 Bjorn Helgaas 提交于 
      Some PCIe features (AER, DPC, hotplug, PME) can be managed by either the
platform firmware or the OS, so the host bridge driver may have to request
permission from the platform before using them.  On ACPI systems, this is
done by negotiate_os_control() in acpi_pci_root_add().

The PCIe port driver later uses pcie_port_platform_notify() and
pcie_port_acpi_setup() to figure out whether it can use these features.
But all we need is a single bit for each service, so these interfaces are
needlessly complicated.

Simplify this by adding bits in the struct pci_host_bridge to show when the
OS has permission to use each feature:

  + unsigned int native_aer:1;       /* OS may use PCIe AER */
  + unsigned int native_hotplug:1;   /* OS may use PCIe hotplug */
  + unsigned int native_pme:1;       /* OS may use PCIe PME */

These are set when we create a host bridge, and the host bridge driver can
clear the bits corresponding to any feature the platform doesn't want us to
use.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      02bfeb48
  17. 22 3月, 2018 1 次提交
  19. 20 3月, 2018 2 次提交
  21. 08 3月, 2018 1 次提交
  23. 05 3月, 2018 1 次提交
  25. 17 2月, 2018 1 次提交
    • B
      PCI: Probe for device reset support during enumeration · 5b0764ca
      由 Bjorn Helgaas 提交于 
      Previously we called pci_probe_reset_function() in this path:

  pci_sysfs_init                              # late_initcall
    for_each_pci_dev(dev)
      pci_create_sysfs_dev_files(dev)
        pci_create_capabilities_sysfs(dev)
          pci_probe_reset_function
            pci_dev_specific_reset
            pcie_has_flr
              pcie_capability_read_dword

pci_sysfs_init() is a late_initcall, and a driver may have already claimed
one of these devices and enabled runtime power management for it, so the
device could already be in D3 by the time we get to pci_sysfs_init().

The device itself should respond to the config read even while it's in
D3hot, but if an upstream bridge is also in D3hot, the read won't even
reach the device because the bridge won't forward it downstream to the
device.  If the bridge is a PCIe port, it should complete the read as an
Unsupported Request, which may be reported to the CPU as an exception or as
invalid data.

Avoid this case by probing for reset support from pci_init_capabilities(),
before a driver can claim the device.  The device may be in D3hot, but any
bridges leading to it should be in D0, so the device's config space should
be fully accessible at that point.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      5b0764ca
  27. 31 1月, 2018 1 次提交
  29. 27 1月, 2018 1 次提交
  31. 19 1月, 2018 1 次提交
  33. 19 12月, 2017 3 次提交
  35. 07 11月, 2017 5 次提交
    • M
      PCI: Distribute available buses to hotplug-capable bridges · 1c02ea81
      由 Mika Westerberg 提交于 
      System BIOS sometimes allocates extra bus space for hotplug-capable PCIe
root/downstream ports. This space is needed if the device plugged to the
port will have more hotplug-capable downstream ports. A good example of
this is Thunderbolt. Each Thunderbolt device contains a PCIe switch and
one or more hotplug-capable PCIe downstream ports where the daisy chain
can be extended.

Currently Linux only allocates minimal bus space to make sure all the
enumerated devices barely fit there. The BIOS reserved extra space is
not taken into consideration at all. Because of this we run out of bus
space pretty quickly when more PCIe devices are attached to hotplug
downstream ports in order to extend the chain.

Modify the PCI core so we distribute the available BIOS allocated bus space
equally between hotplug-capable bridges to make sure there is enough bus
space for extending the hierarchy later on.

Update kernel docs of the affected functions.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      1c02ea81
    • M
      PCI: Do not allocate more buses than available in parent · a20c7f36
      由 Mika Westerberg 提交于 
      One can ask more buses to be reserved for hotplug bridges by passing
pci=hpbussize=N in the kernel command line.  If the parent bus does not
have enough bus space available we incorrectly create child bus with the
requested number of subordinate buses.

In the example below hpbussize is set to one more than we have available
buses in the root port:

  pci 0000:07:00.0: [8086:1578] type 01 class 0x060400
  pci 0000:07:00.0: scanning [bus 00-00] behind bridge, pass 0
  pci 0000:07:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
  pci 0000:07:00.0: scanning [bus 00-00] behind bridge, pass 1
  pci_bus 0000:08: busn_res: can not insert [bus 08-ff] under [bus 07-3f] (conflicts with (null) [bus 07-3f])
  pci_bus 0000:08: scanning bus
  ...
  pci_bus 0000:0a: bus scan returning with max=40
  pci_bus 0000:0a: busn_res: [bus 0a-ff] end is updated to 40
  pci_bus 0000:0a: [bus 0a-40] partially hidden behind bridge 0000:07 [bus 07-3f]
  pci_bus 0000:08: bus scan returning with max=40
  pci_bus 0000:08: busn_res: [bus 08-ff] end is updated to 40

Instead of allowing this, limit the subordinate number to be less than or
equal the maximum subordinate number allocated for the parent bus (if it
has any).
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: remove irrelevant dmesg messages]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      a20c7f36
    • M
      PCI: Open-code the two pass loop when scanning bridges · 4147c2fd
      由 Mika Westerberg 提交于 
      The current scanning code is really hard to understand because it calls
the same function in a loop where pass value is changed without any
comments explaining it:

  for (pass = 0; pass < 2; pass++)
    for_each_pci_bridge(dev, bus)
      max = pci_scan_bridge(bus, dev, max, pass);

Unfamiliar reader cannot tell easily what is the purpose of this loop
without looking at internals of pci_scan_bridge().

In order to make this bit easier to understand, open-code the loop in
pci_scan_child_bus() and pci_hp_add_bridge() with added comments.

No functional changes intended.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      4147c2fd
    • M
      PCI: Move pci_hp_add_bridge() to drivers/pci/probe.c · 95e3ba97
      由 Mika Westerberg 提交于 
      There is not much point of having a file with a single function in it.
Instead we can just move pci_hp_add_bridge() to drivers/pci/probe.c and
make it available always when PCI core is enabled.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: convert printk to dev_err()]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      95e3ba97
    • A
      PCI: Add for_each_pci_bridge() helper · 24a0c654
      由 Andy Shevchenko 提交于 
      The following pattern is often used:

  list_for_each_entry(dev, &bus->devices, bus_list) {
    if (pci_is_bridge(dev)) {
      ...
    }
  }

Add a for_each_pci_bridge() helper to make that code easier to write and
read by reducing indentation level.  It also saves one or few lines of code
in each occurrence.

Convert PCI core parts here at the same time.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: fold in http://lkml.kernel.org/r/20171013165352.25550-1-andriy.shevchenko@linux.intel.com]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      24a0c654
  37. 30 8月, 2017 4 次提交
    • S
      PCI: Warn periodically while waiting for non-CRS ("device ready") status · e78e661f
      由 Sinan Kaya 提交于 
      Add a print statement in pci_bus_wait_crs() so that user observes the
progress of device polling instead of silently waiting for timeout to be
reached.
Signed-off-by: NSinan Kaya <okaya@codeaurora.org>
[bhelgaas: check for timeout first so we don't print "waiting, giving up",
always print time we've slept (not the actual timeout, print a "ready"
message if we've printed a "waiting" message]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      e78e661f
    • S
      PCI: Factor out pci_bus_wait_crs() · 6a802ef0
      由 Sinan Kaya 提交于 
      Configuration Request Retry Status (CRS) was previously hidden inside
pci_bus_read_dev_vendor_id().  We want to add support for CRS in other
situations, such as waiting for a device to become ready after a Function
Level Reset.

Move CRS handling into pci_bus_wait_crs() so it can be called from other
places.
Signed-off-by: NSinan Kaya <okaya@codeaurora.org>
[bhelgaas: pass pointer, not value, to pci_bus_wait_crs() so caller gets
correct Vendor ID]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      6a802ef0
    • S
      PCI: Add pci_bus_crs_vendor_id() to detect CRS response data · 62bc6a6f
      由 Sinan Kaya 提交于 
      Add pci_bus_crs_vendor_id() to determine whether data returned for a config
read of the Vendor ID indicates a Configuration Request Retry Status (CRS)
response.

Per PCIe r3.1, sec 2.3.2, this data is only returned if:

  - CRS Software Visibility is enabled,
  - a config read includes both bytes of the Vendor ID, and
  - the read receives a CRS completion
Signed-off-by: NSinan Kaya <okaya@codeaurora.org>
[bhelgaas: changelog, change name to pci_bus_crs_vendor_id(), make static
in probe.c, use it in pci_bus_read_dev_vendor_id()]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      62bc6a6f
    • B
      PCI: Always check for non-CRS response before timeout · 9f982756
      由 Bjorn Helgaas 提交于 
      While waiting for a device to become ready (i.e., to return a non-CRS
completion to a read of its Vendor ID), if we got a valid response to the
very last read before timing out, we printed a warning and gave up on the
device even though it was actually ready.

For a typical 60s timeout, we wait about 65s (it's not exact because of the
exponential backoff), but we treated devices that became ready between 33s
and 65s as though they failed.

Move the Device ID read later so we check whether the device is ready
before checking for a timeout.

Thanks to Sinan Kaya <okaya@codeaurora.org>, reorder reads so we always
check device presence after sleep, since it's pointless to sleep unless we
recheck afterwards.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      9f982756
  39. 15 8月, 2017 1 次提交
  41. 03 8月, 2017 1 次提交
  43. 01 8月, 2017 1 次提交
  45. 03 7月, 2017 1 次提交
    • L
      PCI: Remove pci_scan_root_bus_msi() · 9ee8a1c4
      由 Lorenzo Pieralisi 提交于 
      The pci_scan_root_bus_bridge() function allows passing a parameterized
struct pci_host_bridge and scanning the resulting PCI bus; since the struct
msi_controller is part of the struct pci_host_bridge and the struct
pci_host_bridge can now be passed to pci_scan_root_bus_bridge() explicitly,
there is no need for a scan interface with a MSI controller parameter.

With all PCI host controller drivers and platform code relying on
pci_scan_root_bus_msi() converted over to pci_scan_root_bus_bridge() the
pci_scan_root_bus_msi() becomes obsolete and can be removed.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      9ee8a1c4
  47. 29 6月, 2017 4 次提交
    • B
      PCI: Enable ECRC only if device supports it · 675734ba
      由 Bjorn Helgaas 提交于 
      John reported that an Intel QuickAssist crypto accelerator didn't work in a
Dell PowerEdge R730.  The problem seems to be that we enabled ECRC when the
device doesn't support it:

  85:00.0 Co-processor [0b40]: Intel Corporation DH895XCC Series QAT [8086:0435]
    Capabilities: [100 v1] Advanced Error Reporting
      AERCap: First Error Pointer: 00, GenCap- CGenEn+ ChkCap- ChkEn+

1302fcf0 ("PCI: Configure *all* devices, not just hot-added ones")
exposed the problem because it applies settings from the _HPX method to all
devices, not just hot-added ones.  The R730 supplies an _HPX method that
allows the kernel to enable ECRC.

Only enable ECRC if the device advertises support for it.

Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1571798
Fixes: 1302fcf0 ("PCI: Configure *all* devices, not just hot-added ones")
Reported-by: NJohn Mazzie <john_mazzie@dell.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      675734ba
    • L
      PCI: Make pci_register_host_bridge() PCI core internal · cea9bc0b
      由 Lorenzo Pieralisi 提交于 
      With the introduction of pci_scan_root_bus_bridge() there is no need to
export pci_register_host_bridge() to other kernel subsystems other than the
PCI compilation unit that needs it.

Make pci_register_host_bridge() static to its compilation unit and convert
the existing drivers usage over to pci_scan_root_bus_bridge().
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
      cea9bc0b
    • L
      PCI: Add pci_scan_root_bus_bridge() interface · 1228c4b6
      由 Lorenzo Pieralisi 提交于 
      The current pci_scan_root_bus() interface is made up of two main code
paths:

  - pci_create_root_bus()
  - pci_scan_child_bus()

pci_create_root_bus() is a wrapper function that allows to create a struct
pci_host_bridge structure, initialize it with the passed parameters and
register it with the kernel.

As the struct pci_host_bridge require additional struct members,
pci_create_root_bus() parameters list has grown in time, making it unwieldy
to add further parameters to it in case the struct pci_host_bridge gains
more members fields to augment its functionality.

Since PCI core code provides functions to allocate struct pci_host_bridge,
instead of forcing the pci_create_root_bus() interface to add new
parameters to cater for new struct pci_host_bridge functionality, it is
more suitable to add an interface in PCI core code to scan a PCI bus
straight from a struct pci_host_bridge created and customized by each
specific PCI host controller driver.

Add a pci_scan_root_bus_bridge() function to allow PCI host controller
drivers to create and initialize struct pci_host_bridge and scan the
resulting bus.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
      1228c4b6
    • L
      PCI: Add devm_pci_alloc_host_bridge() interface · 5c3f18cc
      由 Lorenzo Pieralisi 提交于 
      Struct pci_host_bridge can be allocated by PCI host bridge drivers which
usually allocate and map memory through devm managed interfaces.

Add a devm version for the pci_alloc_host_bridge() interface to simplify
PCI host controller driver porting and simplify the driver failure paths.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
      5c3f18cc