Quite a few ASUS computers experience a nasty problem, related to the
EHCI controllers, when going into system suspend.  It was observed
that the problem didn't occur if the controllers were not put into the
D3 power state before starting the suspend, and commit
151b6128 (USB: EHCI: fix crash during
suspend on ASUS computers) was created to do this.

It turned out this approach messed up other computers that didn't have
the problem -- it prevented USB wakeup from working.  Consequently
commit c2fb8a3f (USB: add
NO_D3_DURING_SLEEP flag and revert 151b6128) was merged; it
reverted the earlier commit and added a whitelist of known good board
names.

Now we know the actual cause of the problem.  Thanks to AceLan Kao for
tracking it down.

According to him, an engineer at ASUS explained that some of their
BIOSes contain a bug that was added in an attempt to work around a
problem in early versions of Windows.  When the computer goes into S3
suspend, the BIOS tries to verify that the EHCI controllers were first
quiesced by the OS.  Nothing's wrong with this, but the BIOS does it
by checking that the PCI COMMAND registers contain 0 without checking
the controllers' power state.  If the register isn't 0, the BIOS
assumes the controller needs to be quiesced and tries to do so.  This
involves making various MMIO accesses to the controller, which don't
work very well if the controller is already in D3.  The end result is
a system hang or memory corruption.

Since the value in the PCI COMMAND register doesn't matter once the
controller has been suspended, and since the value will be restored
anyway when the controller is resumed, we can work around the BIOS bug
simply by setting the register to 0 during system suspend.  This patch
(as1590) does so and also reverts the second commit mentioned above,
which is now unnecessary.

In theory we could do this for every PCI device.  However to avoid
introducing new problems, the patch restricts itself to EHCI host
controllers.

Finally the affected systems can suspend with USB wakeup working
properly.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=37632
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42728Based-on-patch-by: NAceLan Kao <acelan.kao@canonical.com>
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NDâniel Fraga <fragabr@gmail.com>
Tested-by: NJavier Marcet <jmarcet@gmail.com>
Tested-by: NAndrey Rahmatullin <wrar@wrar.name>
Tested-by: NOleksij Rempel <bug-track@fisher-privat.net>
Tested-by: NPavel Pisa <pisa@cmp.felk.cvut.cz>
Cc: stable <stable@vger.kernel.org>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

9d265124 and 15a260d5 added quirks for P2P bridges that support
I/O windows that start/end at 1K boundaries, not just the 4K boundaries
defined by the PCI spec.  For details, see the IOBL_ADR register and the
EN1K bit in the CNF register in the Intel 82870P2 (P64H2).

These quirks complicate the code that reads P2P bridge windows
(pci_read_bridge_io() and pci_cfg_fake_ranges()) because the bridge
I/O resource is updated in the HEADER quirk, in pci_read_bridge_io(),
in pci_setup_bridge(), and again in the FINAL quirk.  This is confusing
and makes it impossible to reassign the bridge windows after FINAL
quirks are run.

This patch adds support for 1K windows in the generic paths, so the
HEADER quirk only has to enable this support.  The FINAL quirk, which
used to undo damage done by pci_setup_bridge(), is no longer needed.

This removes "if (!res->start) res->start = ..." from pci_read_bridge_io();
that was part of 9d265124 to avoid overwriting the resource filled in
by the quirk.  Since pci_read_bridge_io() itself now knows about
granularity, the quirk no longer updates the resource and this test is no
longer needed.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Currently, all of the architectures implement their own pcibios_setup()
routine.  Most of the implementations do nothing so this patch introduces
a generic (__weak) routine in the core that can be used by all
architectures as a default.  If necessary, it can be overridden by
architecture-specific code.
Signed-off-by: NMyron Stowe <myron.stowe@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This patch adds runtime D3cold support and corresponding ACPI platform
support.  This patch only enables runtime D3cold support; it does not
enable D3cold support during system suspend/hibernate.

D3cold is the deepest power saving state for a PCIe device, where its main
power is removed.  While it is in D3cold, you can't access the device at
all, not even its configuration space (which is still accessible in D3hot).
Therefore the PCI PM registers can not be used to transition into/out of
the D3cold state; that must be done by platform logic such as ACPI _PR3.

To support wakeup from D3cold, a system may provide auxiliary power, which
allows a device to request wakeup using a Beacon or the sideband WAKE#
signal.  WAKE# is usually connected to platform logic such as ACPI GPE.
This is quite different from other power saving states, where devices
request wakeup via a PME message on the PCIe link.

Some devices, such as those in plug-in slots, have no direct platform
logic.  For example, there is usually no ACPI _PR3 for them.  D3cold
support for these devices can be done via the PCIe Downstream Port leading
to the device.  When the PCIe port is powered on/off, the device is powered
on/off too.  Wakeup events from the device will be notified to the
corresponding PCIe port.

For more information about PCIe D3cold and corresponding ACPI support,
please refer to:

- PCI Express Base Specification Revision 2.0
- Advanced Configuration and Power Interface Specification Revision 5.0

[bhelgaas: changelog]
Reviewed-by: NRafael J. Wysocki <rjw@sisk.pl>
Originally-by: NZheng Yan <zheng.z.yan@intel.com>
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

pci_intx_mask_supported() assumes INTx masking is supported if the
PCI_COMMAND_INTX_DISABLE bit is writable.  But when that bit is set,
some devices don't actually mask INTx or update PCI_STATUS_INTERRUPT
as we expect.

This patch adds a way for quirks to identify these broken devices.

[bhelgaas: split out from Chelsio quirk addition]
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

We need to put into the resources list for legacy system.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Will use them insert/update busn res in pci_bus struct.

[bhelgaas: print conflicting entry if insertion fails]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The pci_bus secondary/subordinate members are now unused, so remove them.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This adds a busn_res resource in struct pci_bus.  This will replace the
secondary/subordinate members and will be used to build a bus number
resource tree to help with bus number allocation.

[bhelgaas: changelog]
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This patch (as1558) fixes a problem affecting several ASUS computers:
The machine crashes or corrupts memory when going into suspend if the
ehci-hcd driver is bound to any controllers.  Users have been forced
to unbind or unload ehci-hcd before putting their systems to sleep.

After extensive testing, it was determined that the machines don't
like going into suspend when any EHCI controllers are in the PCI D3
power state.  Presumably this is a firmware bug, but there's nothing
we can do about it except to avoid putting the controllers in D3
during system sleep.

The patch adds a new flag to indicate whether the problem is present,
and avoids changing the controller's power state if the flag is set.
Runtime suspend is unaffected; this matters only for system suspend.
However as a side effect, the controller will not respond to remote
wakeup requests while the system is asleep.  Hence USB wakeup is not
functional -- but of course, this is already true in the current state
of affairs.

A similar patch has already been applied as commit
151b6128 (USB: EHCI: fix crash during
suspend on ASUS computers).  The patch supersedes that one and reverts
it.  There are two differences:

	The old patch added the flag at the USB level; this patch
	adds it at the PCI level.

	The old patch applied to all chipsets with the same vendor,
	subsystem vendor, and product IDs; this patch makes an
	exception for a known-good system (based on DMI information).
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NDâniel Fraga <fragabr@gmail.com>
Tested-by: NAndrey Rahmatullin <wrar@wrar.name>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

For returning errors out to non-PCI code.  Re-name xen's version.
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

VFIO PCI support will make use of these for user-initiated
PCI config accesses.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

In a PCI environment, transactions aren't always required to reach
the root bus before being re-routed.  Intermediate switches between
an endpoint and the root bus can redirect DMA back downstream before
things like IOMMUs have a chance to intervene.  Legacy PCI is always
susceptible to this as it operates on a shared bus.  PCIe added a
new capability to describe and control this behavior, Access Control
Services, or ACS.

The utility function pci_acs_enabled() allows us to test the ACS
capabilities of an individual devices against a set of flags while
pci_acs_path_enabled() tests a complete path from a given downstream
device up to the specified upstream device.  We also include the
ability to add device specific tests as it's likely we'll see
devices that do not implement ACS, but want to indicate support
for various capabilities in this space.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The PCI Express Latency Tolerance Reporting (LTR) feature's
pci_ltr_supported() routine is currently only used within
drivers/pci/pci.c so make it static.
Acked-by: NDonald Dutile <ddutile@redhat.com>
Signed-off-by: NMyron Stowe <myron.stowe@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

DMA transactions are tagged with the source ID of the device making
the request.  Occasionally hardware screws this up and uses the
source ID of a different device (often the wrong function number of
a multifunction device).  A specific Ricoh multifunction device is
a prime example of this problem and included in this patch.

Given a pci_dev, this function returns the pci_dev to use as the
source ID for DMA.  When hardware works correctly, this returns
the input device.  For the components of the Ricoh multifunction
device, it returns the pci_dev for function 0.

This will be used by IOMMU drivers for determining the boundaries
of IOMMU groups as multiple devices using the same source ID must
be contained within the same group.  This can also be used by
existing streaming DMA paths for the same purpose.

[bhelgaas: fold in pci_dev_get() for !CONFIG_PCI]
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

pci_bus_find_ext_capability() is unused, and this patch removes it.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

On MIPS we want to call of_irq_map_pci from inside

arch/mips/include/asm/pci.h:extern int pcibios_map_irq(
				const struct pci_dev *dev, u8 slot, u8 pin);
For this to work we need to change several functions to const usage.
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Cc: linux-pci@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-mips@linux-mips.org
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Patchwork: https://patchwork.linux-mips.org/patch/3710/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We need a hook to release host bridge resources allocated when creating
root bus.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Use that device for pci_root_bus bridge pointer.

Use pci_release_bus_bridge_dev() to release allocated pci_host_bridge in
remove path.

Use root bus bridge pointer to get host bridge pointer instead of searching
host bridge list.  That leaves the host bridge list unused, so remove it.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Original EEH implementation depends on struct pci_dn heavily. However,
EEH shouldn't depend on that actually because EEH needn't share much
information with other PCI components. That's to say, EEH should have
worked independently.

The patch introduces struct eeh_dev so that EEH core components needn't
be working based on struct pci_dn in future. Also, struct pci_dn, struct
eeh_dev instances are created in dynamic fasion and the binding with EEH
device, OF node, PCI device is implemented as well.

The EEH devices are created after PHBs are detected and initialized, but
PCI emunation hasn't started yet. Apart from that, PHB might be created
dynamically through DLPAR component and the EEH devices should be creatd
as well. Another case might be OF node is created dynamically by DR
(Dynamic Reconfiguration), which has been defined by PAPR. For those OF
nodes created by DR, EEH devices should be also created accordingly. The
binding between EEH device and OF node is done while the EEH device is
initially created.

The binding between EEH device and PCI device should be done after PCI
emunation is done. Besides, PCI hotplug also needs the binding so that
the EEH devices could be traced from the newly coming PCI buses or PCI
devices.
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Don't switch to pci_remove_bus_device yet, keep the __ prefix for now
(the behavior is still the same: remove without stopping first).

This allows other out of tree users or pending patches to get notified
from compiler warning.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The old pci_remove_behind_bridge actually do stop and remove.

Make the name reflect that to reduce confusion.
Suggested-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The old pci_remove_bus_device actually did stop and remove.

Make the name reflect that to reduce confusion.

This patch is done by sed scripts and changes back some incorrect
__pci_remove_bus_device changes.
Suggested-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Recently added support to allow quirks to report duration also make the
boot log very crowded when initcall_debug is specified.

One thing we can to do mitigate this is to not call quirks unnecessarily
by adding a new quirk declaration macro that takes a class argument.

The new macro takes a class value and a class shift value (since it can
vary) so that quirks will be limited to certain device classes, greatly
reducing the number we call on every PCI device addition.

-v2: fix v1 that left over of sparated patch.
-v3: according to Jesse, change cls to class, cls_shift, to class_shift.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This replaces the generic versions of pcibios_resource_to_bus() and
pcibios_bus_to_resource() in asm-generic/pci.h with versions that use
pci_resource_to_bus() and pci_bus_to_resource().

The replacements are equivalent except that they can apply host
bridge window offsets when the arch has supplied them by using
pci_add_resource_offset().

Each arch can convert to using pci_add_resource_offset() individually by
removing its device resource fixups from pcibios_fixup_bus() and supplying
ARCH_HAS_GENERIC_PCI_OFFSETS.  ARCH_HAS_GENERIC_PCI_OFFSETS can be removed
after all have converted.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Some PCI host bridges apply an address offset, so bus addresses on PCI are
different from CPU addresses.  This patch adds a way for architectures to
tell the PCI core about this offset.  For example:

    LIST_HEAD(resources);
    pci_add_resource_offset(&resources, host->io_space, host->io_offset);
    pci_add_resource_offset(&resources, host->mem_space, host->mem_offset);
    pci_scan_root_bus(parent, bus, ops, sysdata, &resources);
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This adds a list of all PCI host bridges we find and a way to look up
the host bridge from a pci_dev.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Only one user in driver/pci/pci.c, so we don't need to put it in global
pci.h
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This allows us to move the definition of struct resource_list to
setup_bus.c and later convert resource_list to a regular list.
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Current rescan will not touch bridge MMIO and IO.

Try to reuse pci_assign_unassigned_bridge_resources(bridge) to update bridge
resources, if child devices need more resources.

Only do that for bridges whose children are all removed already; i.e. don't
release resources that could already be in use by drivers on child devices.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The use case of this is when a driver wants to call FLR when a device
is attached to it using the SysFS "bind" or "unbind" functionality.

The call chain when a user does "bind" looks as so:

 echo "0000:01.07.0" > /sys/bus/pci/drivers/XXXX/bind

and ends up calling:
  driver_bind:
    device_lock(dev);  <=== TAKES LOCK
    XXXX_probe:
         .. pci_enable_device()
         ...__pci_reset_function(), which calls
                 pci_dev_reset(dev, 0):
                        if (!0) {
                                device_lock(dev) <==== DEADLOCK

The __pci_reset_function_locked function allows the the drivers
'probe' function to call the "pci_reset_function" while still holding
the driver mutex lock.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch converts the underlying maintenance aspects of FW-assigned
BIOS BAR values from a statically allocated array within struct pci_dev
to a list of temporary, stand alone, entries.
Signed-off-by: NMyron Stowe <myron.stowe@redhat.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Commit 58c84eda introduced functionality to try and reinstate the
original BIOS BAR addresses of a PCI device when normal resource
assignment attempts fail.  To keep track of the BIOS BAR addresses,
struct pci_dev was augmented with an array to hold the BAR addresses
of the PCI device: 'resource_size_t fw_addr[DEVICE_COUNT_RESOURCE]'.

The reinstatement of BAR addresses is an uncommon event leaving the
'fw_addr' array unused under normal circumstances.  This functionality
is also currently architecture specific with an implementation limited
to x86.  As the use of struct pci_dev is so prevalent, having the
'fw_addr' array residing within such seems somewhat wasteful.

This patch introduces a stand alone data structure and interfacing
routines for maintaining a list of FW-assigned BIOS BAR value entries.
Signed-off-by: NMyron Stowe <myron.stowe@redhat.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch introduces the module_pci_driver macro which is a convenience
macro for PCI driver modules similar to module_platform_driver. It is
intended to be used by drivers which init/exit section does nothing but
register/unregister the PCI driver. By using this macro it is possible
to eliminate a few lines of boilerplate code per PCI driver.

Based on work done by Lars-Peter Clausen <lars@metafoo.de> for other
busses (i2c and spi).

Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The use case of this is when a driver wants to call FLR when a device
is attached to it using the SysFS "bind" or "unbind" functionality.

The call chain when a user does "bind" looks as so:

 echo "0000:01.07.0" > /sys/bus/pci/drivers/XXXX/bind

and ends up calling:
  driver_bind:
    device_lock(dev);  <=== TAKES LOCK
    XXXX_probe:
         .. pci_enable_device()
         ...__pci_reset_function(), which calls
                 pci_dev_reset(dev, 0):
                        if (!0) {
                                device_lock(dev) <==== DEADLOCK

The __pci_reset_function_locked function allows the the drivers
'probe' function to call the "pci_reset_function" while still holding
the driver mutex lock.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

DEVICE_COUNT_RESOURCE will be bigger than 16 when SRIOV supported is enabled.

Let them pass with int just like pci_enable_resources().
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Save some bytes for device resource array.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

All users of pci_create_bus() have been converted to pci_create_root_bus(),
so remove it.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

I plan to deprecate pci_scan_bus_parented(), so use pci_create_root_bus()
directly instead.  pci_scan_bus() itself will be removed as soon as all
callers are gone, so this is just an interim step.

v2: export pci_scan_bus
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>