Commit Graph

96 Commits

Author SHA1 Message Date
Vladimir Oltean 3a1889c185 PCI: move OF status = "disabled" detection to dev->match_driver
commit 1a8c251cff upstream.

The blamed commit has broken probing on
arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi when &enetc_port0
(PCI function 0) has status = "disabled".

Background: pci_scan_slot() has logic to say that if the function 0 of a
device is absent, the entire device is absent and we can skip the other
functions entirely. Traditionally, this has meant that
pci_bus_read_dev_vendor_id() returns an error code for that function.

However, since the blamed commit, there is an extra confounding
condition: function 0 of the device exists and has a valid vendor id,
but it is disabled in the device tree. In that case, pci_scan_slot()
would incorrectly skip the entire device instead of just that function.

In the case of NXP LS1028A, status = "disabled" does not mean that the
PCI function's config space is not available for reading. It is, but the
Ethernet port is just not functionally useful with a particular SerDes
protocol configuration (0x9999) due to pinmuxing constraints of the Soc.
So, pci_scan_slot() skips all other functions on the ENETC ECAM
(enetc_port1, enetc_port2, enetc_mdio_pf3 etc) when just enetc_port0 had
to not be probed.

There is an additional regression introduced by the change, caused by
its fundamental premise. The enetc driver needs to run code for all PCI
functions, regardless of whether they're enabled or not in the device
tree. That is no longer possible if the driver's probe function is no
longer called. But Rob recommends that we move the of_device_is_available()
detection to dev->match_driver, and this makes the PCI fixups still run
on all functions, while just probing drivers for those functions that
are enabled. So, a separate change in the enetc driver will have to move
the workarounds to a PCI fixup.

Fixes: 6fffbc7ae1 ("PCI: Honor firmware's device disabled status")
Link: https://lore.kernel.org/netdev/CAL_JsqLsVYiPLx2kcHkDQ4t=hQVCR7NHziDwi9cCFUFhx48Qow@mail.gmail.com/
Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:26 +02:00
Linus Torvalds 34b62f186d pci-v6.4-changes
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Merge tag 'pci-v6.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci updates from Bjorn Helgaas:
 "Resource management:

   - Add pci_dev_for_each_resource() and pci_bus_for_each_resource()
     iterators

  PCIe native device hotplug:

   - Fix AB-BA deadlock between reset_lock and device_lock

  Power management:

   - Wait longer for devices to become ready after resume (as we do for
     reset) to accommodate Intel Titan Ridge xHCI devices

   - Extend D3hot delay for NVIDIA HDA controllers to avoid
     unrecoverable devices after a bus reset

  Error handling:

   - Clear PCIe Device Status after EDR since generic error recovery now
     only clears it when AER is native

  ASPM:

   - Work around Chromebook firmware defect that clobbers Capability
     list (including ASPM L1 PM Substates Cap) when returning from
     D3cold to D0

  Freescale i.MX6 PCIe controller driver:

   - Install imprecise external abort handler only when DT indicates
     PCIe support

  Freescale Layerscape PCIe controller driver:

   - Add ls1028a endpoint mode support

  Qualcomm PCIe controller driver:

   - Add SM8550 DT binding and driver support

   - Add SDX55 DT binding and driver support

   - Use bulk APIs for clocks of IP 1.0.0, 2.3.2, 2.3.3

   - Use bulk APIs for reset of IP 2.1.0, 2.3.3, 2.4.0

   - Add DT "mhi" register region for supported SoCs

   - Expose link transition counts via debugfs to help debug low power
     issues

   - Support system suspend and resume; reduce interconnect bandwidth
     and turn off clock and PHY if there are no active devices

   - Enable async probe by default to reduce boot time

  Miscellaneous:

   - Sort controller Kconfig entries by vendor"

* tag 'pci-v6.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (56 commits)
  PCI: xilinx: Drop obsolete dependency on COMPILE_TEST
  PCI: mobiveil: Sort Kconfig entries by vendor
  PCI: dwc: Sort Kconfig entries by vendor
  PCI: Sort controller Kconfig entries by vendor
  PCI: Use consistent controller Kconfig menu entry language
  PCI: xilinx-nwl: Add 'Xilinx' to Kconfig prompt
  PCI: hv: Add 'Microsoft' to Kconfig prompt
  PCI: meson: Add 'Amlogic' to Kconfig prompt
  PCI: Use of_property_present() for testing DT property presence
  PCI/PM: Extend D3hot delay for NVIDIA HDA controllers
  dt-bindings: PCI: qcom: Document msi-map and msi-map-mask properties
  PCI: qcom: Add SM8550 PCIe support
  dt-bindings: PCI: qcom: Add SM8550 compatible
  PCI: qcom: Add support for SDX55 SoC
  dt-bindings: PCI: qcom-ep: Fix the unit address used in example
  dt-bindings: PCI: qcom: Add SDX55 SoC
  dt-bindings: PCI: qcom: Update maintainers entry
  PCI: qcom: Enable async probe by default
  PCI: qcom: Add support for system suspend and resume
  PCI/PM: Drop pci_bridge_wait_for_secondary_bus() timeout parameter
  ...
2023-04-27 10:45:30 -07:00
Andy Shevchenko 02992064bd PCI: Make pci_bus_for_each_resource() index optional
Refactor pci_bus_for_each_resource() in the same way as
pci_dev_for_each_resource(). This allows the index to be hidden inside the
implementation so the caller can omit it when it's not used otherwise.

No functional changes intended.

Link: https://lore.kernel.org/r/20230330162434.35055-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-04-05 15:10:09 -05:00
Niklas Schnelle ab90950985 PCI: s390: Fix use-after-free of PCI resources with per-function hotplug
On s390 PCI functions may be hotplugged individually even when they
belong to a multi-function device. In particular on an SR-IOV device VFs
may be removed and later re-added.

In commit a50297cf82 ("s390/pci: separate zbus creation from
scanning") it was missed however that struct pci_bus and struct
zpci_bus's resource list retained a reference to the PCI functions MMIO
resources even though those resources are released and freed on
hot-unplug. These stale resources may subsequently be claimed when the
PCI function re-appears resulting in use-after-free.

One idea of fixing this use-after-free in s390 specific code that was
investigated was to simply keep resources around from the moment a PCI
function first appeared until the whole virtual PCI bus created for
a multi-function device disappears. The problem with this however is
that due to the requirement of artificial MMIO addreesses (address
cookies) extra logic is then needed to keep the address cookies
compatible on re-plug. At the same time the MMIO resources semantically
belong to the PCI function so tying their lifecycle to the function
seems more logical.

Instead a simpler approach is to remove the resources of an individually
hot-unplugged PCI function from the PCI bus's resource list while
keeping the resources of other PCI functions on the PCI bus untouched.

This is done by introducing pci_bus_remove_resource() to remove an
individual resource. Similarly the resource also needs to be removed
from the struct zpci_bus's resource list. It turns out however, that
there is really no need to add the MMIO resources to the struct
zpci_bus's resource list at all and instead we can simply use the
zpci_bar_struct's resource pointer directly.

Fixes: a50297cf82 ("s390/pci: separate zbus creation from scanning")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20230306151014.60913-2-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-13 09:15:11 +01:00
Bjorn Helgaas 5c5fb3c3a7 PCI: Skip allocate_resource() if too little space available
pci_bus_alloc_from_region() allocates MMIO space by iterating through all
the resources available on the bus.  The available resource might be
reduced if the caller requires 32-bit space or we're avoiding BIOS or E820
areas.

Don't bother calling allocate_resource() if we need more space than is
available in this resource.  This prevents some pointless and annoying
messages about avoided areas.

Link: https://lore.kernel.org/r/20221208190341.1560157-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
2022-12-10 10:31:47 -06:00
Rajat Jain 2194bc7c39 PCI: Add device even if driver attach failed
device_attach() returning failure indicates a driver error while trying to
probe the device. In such a scenario, the PCI device should still be added
in the system and be visible to the user.

When device_attach() fails, merely warn about it and keep the PCI device in
the system.

This partially reverts ab1a187bba ("PCI: Check device_attach() return
value always").

Link: https://lore.kernel.org/r/20200706233240.3245512-1-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org	# v4.6+
2020-07-07 17:33:41 -05:00
Kelsey Skunberg fae6b93b19 PCI: Unexport pci_bus_get() and pci_bus_put()
pci_bus_get() and pci_bus_put() are not used by a loadable kernel module
and do not need to be exported.

These were exported by fe830ef62a ("PCI: Introduce pci_bus_{get|put}() to
manage PCI bus reference count"), but there are no loadable modules in the
tree that use them.

Link: https://lore.kernel.org/r/20190717182353.45557-1-skunberg.kelsey@gmail.com
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-23 18:32:49 -05:00
Mohan Kumar 34c6b7105e PCI: Replace dev_printk(KERN_DEBUG) with dev_info(), etc
Replace dev_printk(KERN_DEBUG) with dev_info(), etc to be more consistent
with other logging and avoid checkpatch warnings.

The KERN_DEBUG messages could be converted to dev_dbg(), but that depends
on CONFIG_DYNAMIC_DEBUG and DEBUG, and we want most of these messages to
*always* be in the dmesg log.

Link: https://lore.kernel.org/lkml/1555733240-19875-1-git-send-email-mohankumar718@gmail.com
Signed-off-by: Mohan Kumar <mohankumar718@gmail.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-05-09 07:49:58 -05:00
Mohan Kumar 25da8dbaaf PCI: Replace printk(KERN_INFO) with pr_info(), etc
Replace printk() with pr_*() to be more consistent with other logging and
avoid checkpatch warnings.

Link: https://lore.kernel.org/lkml/1555733026-19609-1-git-send-email-mohankumar718@gmail.com
Link: https://lore.kernel.org/lkml/1555733130-19804-1-git-send-email-mohankumar718@gmail.com
Signed-off-by: Mohan Kumar <mohankumar718@gmail.com>
[bhelgaas: squash in similar changes from second patch in series]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-05-09 07:49:54 -05:00
Hari Vyas 44bda4b7d2 PCI: Fix is_added/is_busmaster race condition
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=200283
Signed-off-by: Hari Vyas <hari.vyas@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-31 11:27:54 -05:00
Christoph Hellwig 8e6390795e PCI: remove CONFIG_PCI_BUS_ADDR_T_64BIT
This symbol is now always identical to CONFIG_ARCH_DMA_ADDR_T_64BIT, so
remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-09 06:57:18 +02:00
Bjorn Helgaas df62ab5e0f PCI: Tidy comments
Remove pointless comments that tell us the file name, remove blank line
comments, follow multi-line comment conventions.  No functional change
intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-03-19 14:20:43 -05:00
Bjorn Helgaas ab8c609356 Merge branch 'pci/spdx' into next
* pci/spdx:
  PCI: Add SPDX GPL-2.0+ to replace implicit GPL v2 or later statement
  PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
  PCI: Add SPDX GPL-2.0 to replace COPYING boilerplate
  PCI: Add SPDX GPL-2.0 to replace GPL v2 boilerplate
  PCI: Add SPDX GPL-2.0 when no license was specified
2018-02-01 11:40:07 -06:00
Bjorn Helgaas 7328c8f48d PCI: Add SPDX GPL-2.0 when no license was specified
b24413180f ("License cleanup: add SPDX GPL-2.0 license identifier to
files with no license") added SPDX GPL-2.0 to several PCI files that
previously contained no license information.

Add SPDX GPL-2.0 to all other PCI files that did not contain any license
information and hence were under the default GPL version 2 license of the
kernel.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-26 11:45:16 -06:00
Frederick Lawler 7506dc7989 PCI: Add wrappers for dev_printk()
Add PCI-specific dev_printk() wrappers and use them to simplify the code
slightly.  No functional change intended.

Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: squash into one patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-18 12:55:24 -06:00
Lukas Wunner 1ed276a7b9 PCI: Autosense device removal in pci_bridge_d3_update()
The algorithm to update the flag indicating whether a bridge may go to D3
makes a few optimizations based on whether the update was caused by the
removal of a device on the one hand, versus the addition of a device or the
change of its D3cold flags on the other hand.

The information whether the update pertains to a removal is currently
passed in by the caller, but the function may as well determine that itself
by examining the device in question, thereby allowing for a considerable
simplification and reduction of the code.

Out of several options to determine removal, I've chosen the function
device_is_registered() because it's cheap:  It merely returns the
dev->kobj.state_in_sysfs flag.  That flag is set through device_add() when
the root bus is scanned and cleared through device_remove().  The call to
pci_bridge_d3_update() happens after each of these calls, respectively, so
the ordering is correct.

No functional change intended.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-17 18:44:56 -06:00
Bjorn Helgaas 79dd993461 Merge branches 'pci/demodularize-hosts' and 'pci/host-request-windows' into next
* pci/demodularize-hosts:
  PCI: xgene: Make explicitly non-modular
  PCI: thunder-pem: Make explicitly non-modular
  PCI: thunder-ecam: Make explicitly non-modular
  PCI: tegra: Make explicitly non-modular
  PCI: rcar-gen2: Make explicitly non-modular
  PCI: rcar: Make explicitly non-modular
  PCI: mvebu: Make explicitly non-modular
  PCI: layerscape: Make explicitly non-modular
  PCI: keystone: Make explicitly non-modular
  PCI: hisi: Make explicitly non-modular
  PCI: generic: Make explicitly non-modular
  PCI: designware-plat: Make it explicitly non-modular
  PCI: artpec6: Make explicitly non-modular
  PCI: armada8k: Make explicitly non-modular
  PCI: artpec: Add PCI_MSI_IRQ_DOMAIN dependency
  PCI: artpec: Add Axis ARTPEC-6 PCIe controller driver
  PCI: Add DT binding for Axis ARTPEC-6 PCIe controller
  PCI: generic: Select IRQ_DOMAIN

* pci/host-request-windows:
  PCI: versatile: Simplify host bridge window iteration
  PCI: versatile: Request host bridge window resources with core function
  PCI: tegra: Request host bridge window resources with core function
  PCI: tegra: Remove top-level resource from hierarchy
  PCI: rcar: Simplify host bridge window iteration
  PCI: rcar: Request host bridge window resources with core function
  PCI: rcar Gen2: Request host bridge window resources
  PCI: rcar: Drop gen2 dummy I/O port region
  ARM: Make PCI I/O space optional
  PCI: mvebu: Request host bridge window resources with core function
  PCI: generic: Simplify host bridge window iteration
  PCI: generic: Request host bridge window resources with core function
  PCI: altera: Simplify host bridge window iteration
  PCI: altera: Request host bridge window resources with core function
  PCI: xilinx-nwl: Use dev_printk() when possible
  PCI: xilinx-nwl: Request host bridge window resources
  PCI: xilinx-nwl: Free bridge resource list on failure
  PCI: xilinx: Request host bridge window resources
  PCI: xilinx: Free bridge resource list on failure
  PCI: xgene: Request host bridge window resources
  PCI: xgene: Free bridge resource list on failure
  PCI: iproc: Request host bridge window resources
  PCI: designware: Simplify host bridge window iteration
  PCI: designware: Request host bridge window resources
  PCI: designware: Free bridge resource list on failure
  PCI: Add devm_request_pci_bus_resources()
2016-08-01 12:23:57 -05:00
Mika Westerberg 9d26d3a8f1 PCI: Put PCIe ports into D3 during suspend
Currently the Linux PCI core does not touch power state of PCI bridges and
PCIe ports when system suspend is entered.  Leaving them in D0 consumes
power unnecessarily and may prevent the CPU from entering deeper C-states.

With recent PCIe hardware we can power down the ports to save power given
that we take into account few restrictions:

  - The PCIe port hardware is recent enough, starting from 2015.

  - Devices connected to PCIe ports are effectively in D3cold once the port
    is transitioned to D3 (the config space is not accessible anymore and
    the link may be powered down).

  - Devices behind the PCIe port need to be allowed to transition to D3cold
    and back.  There is a way both drivers and userspace can forbid this.

  - If the device behind the PCIe port is capable of waking the system it
    needs to be able to do so from D3cold.

This patch adds a new flag to struct pci_device called 'bridge_d3'.  This
flag is set and cleared by the PCI core whenever there is a change in power
management state of any of the devices behind the PCIe port.  When system
later on is suspended we only need to check this flag and if it is true
transition the port to D3 otherwise we leave it in D0.

Also provide override mechanism via command line parameter
"pcie_port_pm=[off|force]" that can be used to disable or enable the
feature regardless of the BIOS manufacturing date.

Tested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-13 14:57:36 -05:00
Bjorn Helgaas 950334bcf1 PCI: Add devm_request_pci_bus_resources()
Several host bridge drivers iterate through the list of bridge windows to
request resources.  Several others don't request the window resources at
all.

Add a devm_request_pci_bus_resources() interface to make it easier for
drivers to request all the window resources.  Export to GPL modules (from
Arnd Bergmann <arnd@arndb.de>).

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-06-06 15:25:51 -05:00
Lukas Wunner 9a2a5a638f PCI: Do not treat EPROBE_DEFER as device attach failure
Linux 4.5 introduced a behavioral change in device probing during the
suspend process with commit 013c074f86 ("PM / sleep: prohibit devices
probing during suspend/hibernation"): It defers device probing during the
entire suspend process, starting from the prepare phase and ending with the
complete phase.  A rule existed before that "we rely on subsystems not to
do any probing once a device is suspended" but it is enforced only now
(Alan Stern, https://lkml.org/lkml/2015/9/15/908).

This resulted in a WARN splat if a PCI device (e.g., Thunderbolt) is
plugged in while the system is asleep: Upon waking up, pciehp_resume()
discovers new devices in the resume phase and immediately tries to bind
them to a driver.  Since probing is now deferred, device_attach() returns
-EPROBE_DEFER, which provoked a WARN in pci_bus_add_device().

Linux 4.6-rc1 aggravates the situation with commit ab1a187bba ("PCI:
Check device_attach() return value always"): If device_attach() returns a
negative value, pci_bus_add_device() now removes the sysfs and procfs
entries for the device and pci_bus_add_devices() subsequently locks up with
a BUG.  Even with the BUG fixed we're still in trouble because the device
remains on the deferred probing list even though its sysfs and procfs
entries are gone and its children won't be added.

Fix by not interpreting -EPROBE_DEFER as failure.  The device will be
probed eventually (through device_unblock_probing() in dpm_complete()) and
there is proper locking in place to avoid races (e.g., if devices are
unplugged again und thus deleted from the system before deferred probing
happens, I have tested this).  Also, those functions which dereference
dev->driver (e.g. pci_pm_*()) do contain proper NULL pointer checks.  So it
seems safe to ignore -EPROBE_DEFER.

Fixes: ab1a187bba ("PCI: Check device_attach() return value always")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
2016-05-02 13:49:11 -05:00
Lukas Wunner 1e398eae84 PCI: Fix BUG on device attach failure
Previously when pci_bus_add_device() called device_attach() and it returned
a negative value, we emitted a WARN but carried on.

Commit ab1a187bba ("PCI: Check device_attach() return value always"),
introduced in Linux 4.6-rc1, changed this to unwind all steps preceding
device_attach() and to not set dev->is_added = 1.

The latter leads to a BUG if pci_bus_add_device() was called from
pci_bus_add_devices().  Fix by not recursing to a child bus if
device_attach() failed for the bridge leading to it.

This can be triggered by plugging in a PCI device (e.g. Thunderbolt) while
the system is asleep.  The system locks up when woken because
device_attach() returns -EPROBE_DEFER.

Fixes: ab1a187bba ("PCI: Check device_attach() return value always")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-02 13:48:25 -05:00
Linus Torvalds d5e2d00898 powerpc updates for 4.6
Highlights:
  - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras
  - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V
  - Add POWER9 cputable entry from Michael Neuling
  - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
  - Add support for new ftrace ABI on ppc64le from Torsten Duwe
 
 Various cleanups & minor fixes from:
  - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril
    Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey,
    Sukadev Bhattiprolu, Suraj Jitindar Singh.
 
 General:
  - atomics: Allow architectures to define their own __atomic_op_* helpers from
    Boqun Feng
  - Implement atomic{, 64}_*_return_* variants and acquire/release/relaxed
    variants for (cmp)xchg from Boqun Feng
  - Add powernv_defconfig from Jeremy Kerr
  - Fix BUG_ON() reporting in real mode from Balbir Singh
  - Add xmon command to dump OPAL msglog from Andrew Donnellan
  - Add xmon command to dump process/task similar to ps(1) from Douglas Miller
  - Clean up memory hotplug failure paths from David Gibson
 
 pci/eeh:
  - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei
    Yang.
  - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
  - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
  - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
  - MAINTAINERS: Update EEH details and maintainership from Russell Currey
 
 cxl:
  - Support added to the CXL driver for running on both bare-metal and
    hypervisor systems, from Christophe Lombard and Frederic Barrat.
  - Ignore probes for virtual afu pci devices from Vaibhav Jain
 
 perf:
  - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu
  - hv-24x7: Fix usage with chip events, display change in counter values,
    display domain indices in sysfs, eliminate domain suffix in event names,
    from Sukadev Bhattiprolu
 
 Freescale:
  - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum
    optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and
    other dt bits, and minor fixes/cleanup."
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Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "This was delayed a day or two by some build-breakage on old toolchains
  which we've now fixed.

  There's two PCI commits both acked by Bjorn.

  There's one commit to mm/hugepage.c which is (co)authored by Kirill.

  Highlights:
   - Restructure Linux PTE on Book3S/64 to Radix format from Paul
     Mackerras
   - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh
     Kumar K.V
   - Add POWER9 cputable entry from Michael Neuling
   - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
   - Add support for new ftrace ABI on ppc64le from Torsten Duwe

  Various cleanups & minor fixes from:
   - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy,
     Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell
     Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh.

  General:
   - atomics: Allow architectures to define their own __atomic_op_*
     helpers from Boqun Feng
   - Implement atomic{, 64}_*_return_* variants and acquire/release/
     relaxed variants for (cmp)xchg from Boqun Feng
   - Add powernv_defconfig from Jeremy Kerr
   - Fix BUG_ON() reporting in real mode from Balbir Singh
   - Add xmon command to dump OPAL msglog from Andrew Donnellan
   - Add xmon command to dump process/task similar to ps(1) from Douglas
     Miller
   - Clean up memory hotplug failure paths from David Gibson

  pci/eeh:
   - Redesign SR-IOV on PowerNV to give absolute isolation between VFs
     from Wei Yang.
   - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
   - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
   - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
   - MAINTAINERS: Update EEH details and maintainership from Russell
     Currey

  cxl:
   - Support added to the CXL driver for running on both bare-metal and
     hypervisor systems, from Christophe Lombard and Frederic Barrat.
   - Ignore probes for virtual afu pci devices from Vaibhav Jain

  perf:
   - Export Power8 generic and cache events to sysfs from Sukadev
     Bhattiprolu
   - hv-24x7: Fix usage with chip events, display change in counter
     values, display domain indices in sysfs, eliminate domain suffix in
     event names, from Sukadev Bhattiprolu

  Freescale:
   - Updates from Scott: "Highlights include 8xx optimizations, 32-bit
     checksum optimizations, 86xx consolidation, e5500/e6500 cpu
     hotplug, more fman and other dt bits, and minor fixes/cleanup"

* tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc: Fix unrecoverable SLB miss during restore_math()
  powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers
  powerpc/rcpm: Fix build break when SMP=n
  powerpc/book3e-64: Use hardcoded mttmr opcode
  powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible
  powerpc/T104xRDB: add tdm riser card node to device tree
  powerpc32: PAGE_EXEC required for inittext
  powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree
  powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)
  powerpc/86xx: Introduce and use common dtsi
  powerpc/86xx: Update device tree
  powerpc/86xx: Move dts files to fsl directory
  powerpc/86xx: Switch to kconfig fragments approach
  powerpc/86xx: Update defconfigs
  powerpc/86xx: Consolidate common platform code
  powerpc32: Remove one insn in mulhdu
  powerpc32: small optimisation in flush_icache_range()
  powerpc: Simplify test in __dma_sync()
  powerpc32: move xxxxx_dcache_range() functions inline
  powerpc32: Remove clear_pages() and define clear_page() inline
  ...
2016-03-19 15:38:41 -07:00
Wei Yang 7b77061f8d PCI: Add pcibios_bus_add_device() weak function
This adds weak function pcibios_bus_add_device() for arch dependent
code could do proper setup. For example, powerpc could setup EEH
related resources for SRIOV VFs.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-09 09:58:14 +11:00
Bjorn Helgaas ab1a187bba PCI: Check device_attach() return value always
Previously we checked the device_attach() return value only when
CONFIG_BUG=y.  That caused this warning in builds where CONFIG_BUG is not
set:

  drivers/pci/bus.c:237:6: warning: variable 'retval' set but not used [-Wunused-but-set-variable]

Check the return value of device_attach() always and clean up after
failure.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-05 14:56:57 -06:00
Christoph Biedl 3460baa620 PCI: Fix minimum allocation address overwrite
Commit 36e097a8a2 ("PCI: Split out bridge window override of minimum
allocation address") claimed to do no functional changes but unfortunately
did: The "min" variable is altered.  At least the AVM A1 PCMCIA adapter was
no longer detected, breaking ISDN operation.

Use a local copy of "min" to restore the previous behaviour.

[bhelgaas: avoid gcc "?:" extension for portability and readability]
Fixes: 36e097a8a2 ("PCI: Split out bridge window override of minimum allocation address")
Signed-off-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org      # v3.14+
2016-01-06 15:37:55 -06:00
Bjorn Helgaas b838b39e93 PCI: Clear IORESOURCE_UNSET when clipping a bridge window
c770cb4cb5 ("PCI: Mark invalid BARs as unassigned") sets IORESOURCE_UNSET
if we fail to claim a resource.  If we tried to claim a bridge window,
failed, clipped the window, and tried to claim the clipped window, we
failed again because of IORESOURCE_UNSET:

  pci_bus 0000:00: root bus resource [mem 0xc0000000-0xffffffff window]
  pci 0000:00:01.0: can't claim BAR 15 [mem 0xbdf00000-0xddefffff 64bit pref]: no compatible bridge window
  pci 0000:00:01.0: [mem size 0x20000000 64bit pref] clipped to [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0:   bridge window [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0: can't claim BAR 15 [mem size 0x1df00000 64bit pref]: no address assigned

The 00:01.0 window started as [mem 0xbdf00000-0xddefffff 64bit pref].  That
starts before the host bridge window [mem 0xc0000000-0xffffffff window], so
we clipped the 00:01.0 window to [mem 0xc0000000-0xddefffff 64bit pref].
But we left it marked IORESOURCE_UNSET, so the second claim failed when it
should have succeeded.

This means downstream devices will also fail for lack of resources, e.g.,
in the bugzilla below,

  radeon 0000:01:00.0: Fatal error during GPU init

Clear IORESOURCE_UNSET when we clip a bridge window.  Also clear
IORESOURCE_UNSET in our copy of the unclipped window so we can see exactly
what the original window was and how it now fits inside the upstream
window.

Fixes: c770cb4cb5 ("PCI: Mark invalid BARs as unassigned")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491#c47
Based-on-patch-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Based-on-patch-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
CC: stable@vger.kernel.org	# v4.1+
2015-09-22 17:03:54 -05:00
Yinghai Lu 3a9ad0b4fd PCI: Add pci_bus_addr_t
David Ahern reported that d63e2e1f3d ("sparc/PCI: Clip bridge windows
to fit in upstream windows") fails to boot on sparc/T5-8:

  pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address 0x110204000)

The problem is that sparc64 assumed that dma_addr_t only needed to hold DMA
addresses, i.e., bus addresses returned via the DMA API (dma_map_single(),
etc.), while the PCI core assumed dma_addr_t could hold *any* bus address,
including raw BAR values.  On sparc64, all DMA addresses fit in 32 bits, so
dma_addr_t is a 32-bit type.  However, BAR values can be 64 bits wide, so
they don't fit in a dma_addr_t.  d63e2e1f3d added new checking that
tripped over this mismatch.

Add pci_bus_addr_t, which is wide enough to hold any PCI bus address,
including both raw BAR values and DMA addresses.  This will be 64 bits
on 64-bit platforms and on platforms with a 64-bit dma_addr_t.  Then
dma_addr_t only needs to be wide enough to hold addresses from the DMA API.

[bhelgaas: changelog, bugzilla, Kconfig to ensure pci_bus_addr_t is at
least as wide as dma_addr_t, documentation]
Fixes: d63e2e1f3d ("sparc/PCI: Clip bridge windows to fit in upstream windows")
Fixes: 23b13bc76f ("PCI: Fail safely if we can't handle BARs larger than 4GB")
Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
Link: http://lkml.kernel.org/r/1427857069-6789-1-git-send-email-yinghai@kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=96231
Reported-by: David Ahern <david.ahern@oracle.com>
Tested-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: stable@vger.kernel.org	# v3.19+
2015-05-29 17:21:45 -05:00
Jiang Liu 14d76b68f2 PCI: Use common resource list management code instead of private implementation
Use common resource list management data structure and interfaces
instead of private implementation.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-05 15:09:25 +01:00
Yinghai Lu 0f7e7aee2f PCI: Add pci_bus_clip_resource() to clip to fit upstream window
Add pci_bus_clip_resource().  If a PCI-PCI bridge window overlaps an
upstream bridge window but is not completely contained by it, this clips
the downstream window so it fits inside the upstream one.

No functional change (this adds the function but no callers).

[bhelgaas: changelog, split into separate patch]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491
Reported-by: Marek Kordik <kordikmarek@gmail.com>
Fixes: 5b28541552 ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources")
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.16+
2015-01-16 10:04:42 -06:00
Ryan Desfosses b7fe943421 PCI: Move EXPORT_SYMBOL so it immediately follows function/variable
Move EXPORT_SYMBOL so it immediately follows the function or variable.

No functional change.

[bhelgaas: squash similar changes, fix hotplug, probe, rom, search, too]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-10 13:36:10 -06:00
Yijing Wang c893d133ea PCI: Make pci_bus_add_device() void
pci_bus_add_device() always returns 0, so there's no point in returning
anything at all.  Make it a void function and remove the tests of the
return value from the callers.

[bhelgaas: changelog, remove unused "err" from i82875p_setup_overfl_dev()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-30 09:34:27 -06:00
Paul Gortmaker 56a3d18279 PCI: Remove unnecessary includes of <linux/init.h>
None of these files are actually using any __init type directives and hence
don't need to include <linux/init.h>.   Most are just a left over from
__devinit and __cpuinit removal, or simply due to code getting copied from
one driver to the next.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-04-14 16:12:37 -06:00
Bjorn Helgaas 664c28480c PCI: Change pci_bus_alloc_resource() type_mask to unsigned long
The pci_bus_alloc_resource() "type_mask" parameter is used to compare with
the "flags" member of a struct resource, so it should be the same type,
namely "unsigned long".

No functional change because all current IORESOURCE_* flags fit in 32 bits.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-03-19 15:00:16 -06:00
Bjorn Helgaas aa11fc58dc PCI: Check all IORESOURCE_TYPE_BITS in pci_bus_alloc_from_region()
When allocating space from a bus resource, i.e., from apertures leading to
this bus, make sure the entire resource type matches.  The previous code
assumed the IORESOURCE_TYPE_BITS field was a bitmask with only a single bit
set, but this is not true.  IORESOURCE_TYPE_BITS is really an enumeration,
and we have to check all the bits.

See 72dcb11972 ("resources: Add register address resource type").

No functional change.  If we used this path for allocating IRQs, DMA
channels, or bus numbers, this would fix a bug because those types are
indistinguishable when masked by IORESOURCE_IO | IORESOURCE_MEM.  But we
don't, so this shouldn't make any difference.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-03-19 15:00:16 -06:00
Bjorn Helgaas e20fa6609a PCI: Don't check resource_size() in pci_bus_alloc_resource()
Paul reported that after f75b99d5a7 ("PCI: Enforce bus address limits in
resource allocation") on a 32-bit kernel (CONFIG_PHYS_ADDR_T_64BIT not
set), intel-gtt complained "can't ioremap flush page - no chipset
flushing".  In addition, other PCI resource allocations, e.g., for bridge
windows, failed.

This happens because we incorrectly skip bus resources of
[mem 0x00000000-0xffffffff] because we think they are of size zero.
When resource_size_t is 32 bits wide, resource_size() on
[mem 0x00000000-0xffffffff] returns 0 because (r->end - r->start + 1)
overflows.

Therefore, we can't use "resource_size() == 0" to decide that allocation
from this resource will fail.  allocate_resource() should fail anyway if it
can't satisfy the address constraints, so we should just depend on that.

A [mem 0x00000000-0xffffffff] bus resource is obviously not really valid,
but we do fall back to it as a default when we don't have information about
host bridge apertures.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=71611
Fixes: f75b99d5a7 PCI: Enforce bus address limits in resource allocation
Reported-and-tested-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-03-19 15:00:16 -06:00
Bjorn Helgaas 96702be560 Merge branch 'pci/resource' into next
* pci/resource:
  PCI: Allocate 64-bit BARs above 4G when possible
  PCI: Enforce bus address limits in resource allocation
  PCI: Split out bridge window override of minimum allocation address
  agp/ati: Use PCI_COMMAND instead of hard-coded 4
  agp/intel: Use CPU physical address, not bus address, for ioremap()
  agp/intel: Use pci_bus_address() to get GTTADR bus address
  agp/intel: Use pci_bus_address() to get MMADR bus address
  agp/intel: Support 64-bit GMADR
  agp/intel: Rename gtt_bus_addr to gtt_phys_addr
  drm/i915: Rename gtt_bus_addr to gtt_phys_addr
  agp: Use pci_resource_start() to get CPU physical address for BAR
  agp: Support 64-bit APBASE
  PCI: Add pci_bus_address() to get bus address of a BAR
  PCI: Convert pcibios_resource_to_bus() to take a pci_bus, not a pci_dev
  PCI: Change pci_bus_region addresses to dma_addr_t
2014-01-10 14:23:15 -07:00
Yinghai Lu d56dbf5bab PCI: Allocate 64-bit BARs above 4G when possible
Try to allocate space for 64-bit BARs above 4G first, to preserve the space
below 4G for 32-bit BARs.  If there's no space above 4G available, fall
back to allocating anywhere.

[bhelgaas: reworked starting from http://lkml.kernel.org/r/1387485843-17403-2-git-send-email-yinghai@kernel.org]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-07 16:24:33 -07:00
Yinghai Lu f75b99d5a7 PCI: Enforce bus address limits in resource allocation
When allocating space for 32-bit BARs, we previously limited RESOURCE
addresses so they would fit in 32 bits.  However, the BUS address need not
be the same as the resource address, and it's the bus address that must fit
in the 32-bit BAR.

This patch adds:

  - pci_clip_resource_to_region(), which clips a resource so it contains
    only the range that maps to the specified bus address region, e.g., to
    clip a resource to 32-bit bus addresses, and

  - pci_bus_alloc_from_region(), which allocates space for a resource from
    the specified bus address region,

and changes pci_bus_alloc_resource() to allocate space for 64-bit BARs from
the entire bus address region, and space for 32-bit BARs from only the bus
address region below 4GB.

If we had this window:

  pci_root HWP0002:0a: host bridge window [mem 0xf0180000000-0xf01fedfffff] (bus address [0x80000000-0xfedfffff])

we previously could not put a 32-bit BAR there, because the CPU addresses
don't fit in 32 bits.  This patch fixes this, so we can use this space for
32-bit BARs.

It's also possible (though unlikely) to have resources with 32-bit CPU
addresses but bus addresses above 4GB.  In this case the previous code
would allocate space that a 32-bit BAR could not map.

Remove PCIBIOS_MAX_MEM_32, which is no longer used.

[bhelgaas: reworked starting from http://lkml.kernel.org/r/1386658484-15774-3-git-send-email-yinghai@kernel.org]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-07 16:24:33 -07:00
Bjorn Helgaas 36e097a8a2 PCI: Split out bridge window override of minimum allocation address
pci_bus_alloc_resource() avoids allocating space below the "min" supplied
by the caller (usually PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM).  This is to
protect badly documented motherboard resources.  But if we're allocating
space inside an already-configured PCI-PCI bridge window, we ignore "min".

See 688d191821 ("pci: make bus resource start address override minimum IO
address").

This patch moves the check to make it more visible and simplify future
patches.  No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-07 16:24:33 -07:00
Yinghai Lu ef37702eb3 PCI: Move pci_proc_attach_device() to pci_bus_add_device()
4f535093cf ("PCI: Put pci_dev in device tree as early as possible")
moved pci_proc_attach_device() from pci_bus_add_device() to
pci_device_add().

This moves it back to pci_bus_add_device(), essentially reverting that
part of 4f535093cf.  This makes it symmetric with pci_stop_dev(),
where we call pci_proc_detach_device() and pci_remove_sysfs_dev_files()
and set dev->is_added = 0.

[bhelgaas: changelog, create sysfs then attach proc for symmetry]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-12-18 13:53:38 -07:00
Yinghai Lu 928bea9648 PCI: Delay enabling bridges until they're needed
We currently enable PCI bridges after scanning a bus and assigning
resources.  This is often done in arch code.

This patch changes this so we don't enable a bridge until necessary, i.e.,
until we enable a PCI device behind the bridge.  We do this in the generic
pci_enable_device() path, so this also removes the arch-specific code to
enable bridges.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-07-25 12:35:03 -06:00
Jiang Liu fe830ef62a PCI: Introduce pci_bus_{get|put}() to manage PCI bus reference count
Introduce helper functions pci_bus_{get|put}() to manage PCI bus
reference count.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-05-27 16:22:09 -06:00
Yinghai Lu e253aaf0af PCI: Delay final fixups until resources are assigned
Commit 4f535093cf "PCI: Put pci_dev in device tree as early as possible"
moved final fixups from pci_bus_add_device() to pci_device_add().  But
pci_device_add() happens before resource assignment, so BARs may not be
valid yet.

Typical flow for hot-add:

    pciehp_configure_device
      pci_scan_slot
        pci_scan_single_device
          pci_device_add
            pci_fixup_device(pci_fixup_final, dev)  # previous location
      # resource assignment happens here
      pci_bus_add_devices
        pci_bus_add_device
          pci_fixup_device(pci_fixup_final, dev)    # new location

[bhelgaas: changelog, move fixups to pci_bus_add_device()]
Reference: https://lkml.kernel.org/r/20130415182614.GB9224@xanatos
Reported-by: David Bulkow <David.Bulkow@stratus.com>
Tested-by: David Bulkow <David.Bulkow@stratus.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.9+
2013-05-07 14:35:44 -06:00
Bjorn Helgaas 723ec4d06c Merge branch 'pci/cleanup' into next
* pci/cleanup:
  PCI: Remove "extern" from function declarations
  PCI: Warn about failures instead of "must_check" functions
  PCI: Remove __must_check from definitions
  PCI: Remove unused variables
  PCI: Move cpci_hotplug_init() proto to header file
  PCI: Make local functions/structs static
  PCI: Fix missing prototype for pcie_port_acpi_setup()

Conflicts:
	drivers/pci/hotplug/acpiphp.h
	include/linux/pci.h
2013-04-17 10:31:34 -06:00
Bjorn Helgaas 9fc9eea09f PCI: Warn about failures instead of "must_check" functions
These places capture return values to avoid "must_check" warnings,
but we didn't *do* anything with the return values, which causes
"set but not used" warnings.  We might as well do something instead
of just trying to evade the "must_check" warnings.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-04-17 10:21:12 -06:00
Jiang Liu 981cf9ea9a PCI: Clean up usages of pci_bus->is_added
Now pci_bus->is_added is only used to guard invoking of
pcibios_fixup_bus() in pci_scan_child_bus(), so just set
it directly after the fixups and remove the other test
and set in pci_bus_add_devices().

[bhelgaas: changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
2013-04-12 15:38:25 -06:00
Yinghai Lu 4f535093cf PCI: Put pci_dev in device tree as early as possible
We want to put pci_dev structs in the device tree as soon as possible so
for_each_pci_dev() iteration will not miss them, but driver attachment
needs to be delayed until after pci_assign_unassigned_resources() to make
sure all devices have resources assigned first.

This patch moves device registering from pci_bus_add_devices() to
pci_device_add(), which happens earlier, leaving driver attachment in
pci_bus_add_devices().

It also removes unattached child bus handling in pci_bus_add_devices().
That's not needed because child bus via pci_add_new_bus() is already
in parent bus children list.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-25 16:22:37 -07:00
Yinghai Lu 58d9a38f6f PCI: Skip attaching driver in device_add()
We want to add PCI devices to the device tree as early as possible but
delay attaching drivers.

device_add() adds a device to the device hierarchy and (via
device_attach()) attaches a matching driver and calls its .probe() method.
We want to separate adding the device to the hierarchy from attaching the
driver.

This patch does that by adding "match_driver" in struct pci_dev.  When
false, we return failure from pci_bus_match(), which makes device_attach()
believe there's no matching driver.

Later, we set "match_driver = true" and call device_attach() again, which
now attaches the driver and calls its .probe() method.

[bhelgaas: changelog, explicitly init dev->match_driver,
fold device_attach() call into pci_bus_add_device()]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-25 15:10:12 -07:00
Yinghai Lu 3c449ed007 PCI/ACPI: Reserve firmware-allocated resources for hot-added root buses
Firmware may have assigned PCI BARs for hot-added devices, so reserve
those resources before trying to allocate more.

[bhelgaas: move empty weak definition here]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-07 15:58:48 -07:00
Bjorn Helgaas 72e1e868ca Merge branch 'pci/mjg-pci-roms-from-efi' into next
* pci/mjg-pci-roms-from-efi:
  x86: Use PCI setup data
  PCI: Add support for non-BAR ROMs
  PCI: Add pcibios_add_device
  EFI: Stash ROMs if they're not in the PCI BAR
2012-12-06 14:37:32 -07:00