The pm_request_idle() in pm_generic_complete() is pointless as it is
called with the runtime PM usage counter different from zero (bumped
up by the core during the prepare phase of system suspend) and the
core calls pm_runtime_put() for all devices after executing their
complete callbacks, so drop it.

This allows the PCI PM layer to use pm_generic_complete() too.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>

Commit bac2a909 (PCI / PM: Avoid resuming PCI devices during
system suspend) introduced a mechanism by which some PCI devices that
were runtime-suspended at the system suspend time might be left in
that state for the duration of the system suspend-resume cycle.
However, it overlooked devices that were marked as capable of waking
up the system just because PME support was detected in their PCI
config space.

Namely, in that case, device_can_wakeup(dev) returns 'true' for the
device and if the device is not configured for system wakeup,
device_may_wakeup(dev) returns 'false' and it will be resumed during
system suspend even though configuring it for system wakeup may not
really make sense at all.

To avoid this problem, simply disable PME for PCI devices that have
not been configured for system wakeup and are runtime-suspended at
the system suspend time for the duration of the suspend-resume cycle.

If the device is in D3cold, its config space is not available and it
shouldn't be written to, but that's only possible if the device
has platform PM support and the platform code is responsible for
checking whether or not the device's configuration is suitable for
system suspend in that case.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Section 3.2 "Device Runtime Power Management" of pci.txt has become
outdated, so update it to correctly reflect the current code flow.

Also update the comment in local_pci_probe() to document the fact
that pm_runtime_put_noidle() is not the only runtime PM helper
function that can be used to decrement the device's runtime PM
usage counter in .probe().
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

Add Renesas R8A7794 SoC support to the Renesas R-Car gen2 PCI driver.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>

932c435c ("PCI: Add dev_flags bit to access VPD through function 0")
added PCI_DEV_FLAGS_VPD_REF_F0.  Previously, we set the flag on every
non-zero function of quirked devices.  If a function turned out to be
different from function 0, i.e., it had a different class, vendor ID, or
device ID, the flag remained set but we didn't make VPD accessible at all.

Flip this around so we only set PCI_DEV_FLAGS_VPD_REF_F0 for functions that
are identical to function 0, and allow regular VPD access for any other
functions.

[bhelgaas: changelog, stable tag]
Fixes: 932c435c ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>
Acked-by: NMyron Stowe <myron.stowe@redhat.com>
Acked-by: NMark Rustad <mark.d.rustad@intel.com>
CC: stable@vger.kernel.org

Commit 932c435c ("PCI: Add dev_flags bit to access VPD through function
0") passes PCI_SLOT(devfn) for the devfn parameter of pci_get_slot().
Generally this works because we're fairly well guaranteed that a PCIe
device is at slot address 0, but for the general case, including
conventional PCI, it's incorrect.  We need to get the slot and then convert
it back into a devfn.

Fixes: 932c435c ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>
Acked-by: NMyron Stowe <myron.stowe@redhat.com>
Acked-by: NMark Rustad <mark.d.rustad@intel.com>
CC: stable@vger.kernel.org

SR-IOV creates a virtual bus where bus->self is NULL.  When we add VFs and
scan for an MSI domain, pci_set_bus_msi_domain() dereferences bus->self,
which causes a kernel NULL pointer dereference oops.

Scan up to the parent bus until we find a real bridge where we can get the
MSI domain.

[bhelgaas: changelog]
Fixes: 44aa0c65 ("PCI/MSI: Add hooks to populate the msi_domain field")
Tested-by: NJoerg Roedel <joro@8bytes.org>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>

c770cb4c ("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: c770cb4c ("PCI: Mark invalid BARs as unassigned")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491#c47Based-on-patch-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Based-on-patch-by: NYinghai Lu <yinghai@kernel.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
CC: stable@vger.kernel.org	# v4.1+

Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>

Revert dff22d20 ("PCI: Call pci_read_bridge_bases() from core instead
of arch code").

Reading PCI bridge windows is not arch-specific in itself, but there is PCI
core code that doesn't work correctly if we read them too early.  For
example, Hannes found this case on an ARM Freescale i.mx6 board:

  pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff]
  pci 0000:00:00.0: PCI bridge to [bus 01-ff]
  pci 0000:00:00.0: BAR 8: no space for [mem size 0x01000000] (mem window)
  pci 0000:01:00.0: BAR 2: failed to assign [mem size 0x00200000]
  pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x00004000]
  pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x00000100]

The 00:00.0 mem window needs to be at least 3MB: the 01:00.0 device needs
0x204100 of space, and mem windows are megabyte-aligned.

Bus sizing can increase a bridge window size, but never *decrease* it (see
d65245c3 ("PCI: don't shrink bridge resources")).  Prior to
dff22d20, ARM didn't read bridge windows at all, so the "original size"
was zero, and we assigned a 3MB window.

After dff22d20, we read the bridge windows before sizing the bus.  The
firmware programmed a 16MB window (size 0x01000000) in 00:00.0, and since
we never decrease the size, we kept 16MB even though we only needed 3MB.
But 16MB doesn't fit in the host bridge aperture, so we failed to assign
space for the window and the downstream devices.

I think this is a defect in the PCI core: we shouldn't rely on the firmware
to assign sensible windows.

Ray reported a similar problem, also on ARM, with Broadcom iProc.

Issues like this are too hard to fix right now, so revert dff22d20.
Reported-by: NHannes <oe5hpm@gmail.com>
Reported-by: NRay Jui <rjui@broadcom.com>
Link: http://lkml.kernel.org/r/CAAa04yFQEUJm7Jj1qMT57-LG7ZGtnhNDBe=PpSRa70Mj+XhW-A@mail.gmail.com
Link: http://lkml.kernel.org/r/55F75BB8.4070405@broadcom.comSigned-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NDave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 3a9ad0b4 ("PCI: Add pci_bus_addr_t") unconditionally introduced usage of
64-bit PCI bus addresses on all 64-bit platforms which broke PA-RISC.

It turned out that due to enabling the 64-bit addresses, the PCI logic decided
to use the GMMIO instead of the LMMIO region. This commit simply disables
registering the GMMIO and thus we fall back to use the LMMIO region as before.

Reverts commit 45ea2a5f
("PCI: Don't use 64-bit bus addresses on PA-RISC")

To: linux-parisc@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: stable@vger.kernel.org  # v3.19+
Signed-off-by: NHelge Deller <deller@gmx.de>

Commit 1851617c ("PCI/MSI: Disable MSI at enumeration even if kernel
doesn't support MSI") changed the location of the code that initialises
dev->msi_cap/msix_cap and then disables MSI/MSI-X interrupts at PCI
probe time in devices that have this flag set. It moved the code from
pci_msi_init_pci_dev() to a new function named pci_msi_setup_pci_dev(),
called by pci_setup_device().

The pseries PCI probing code does not call pci_setup_device(), so since
the aforementioned commit the function pci_msi_setup_pci_dev() is not
called and MSI/MSI-X interrupts are left enabled. Additionally because
dev->msi_cap/msix_cap are not initialised no driver can ever enable
MSI/MSI-X.

To fix this, the pseries PCI probe should manually call
pci_msi_setup_pci_dev(), so this patch makes it non-static.

Fixes: 1851617c ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't support MSI")
[mpe: Update change log to mention dev->msi_cap/msix_cap]
Signed-off-by: NGuilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This lets drivers take advantage of PAT when available. It
should help with the transition of converting video drivers over
to ioremap_wc() to help with the goal of eventually using
_PAGE_CACHE_UC over _PAGE_CACHE_UC_MINUS on x86 on
ioremap_nocache(), see:

  de33c442 ("x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()")
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Cc: <syrjala@sci.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Ville Syrjälä <syrjala@sci.fi>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: airlied@linux.ie
Cc: benh@kernel.crashing.org
Cc: dan.j.williams@intel.com
Cc: konrad.wilk@oracle.com
Cc: linux-fbdev@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: mst@redhat.com
Cc: vinod.koul@intel.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1440443613-13696-2-git-send-email-mcgrof@do-not-panic.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

On multi-function JMicron SATA/PATA/AHCI devices, the PATA controller at
function 1 doesn't work if it is powered on before the SATA controller at
function 0.  The result is that PATA doesn't work after resume, and we
print messages like this:

  pata_jmicron 0000:02:00.1: Refused to change power state, currently in D3
  irq 17: nobody cared (try booting with the "irqpoll" option)

Async resume was introduced in v3.15 by 76569faa ("PM / sleep:
Asynchronous threads for resume_noirq").  Prior to that, we powered on
the functions in order, so this problem shouldn't happen.

e6b7e41c ("ata: Disabling the async PM for JMicron chip 363/361")
solved the problem for JMicron 361 and 363 devices.  With async suspend
disabled, we always power on function 0 before function 1.

Barto then reported the same problem with a JMicron 368 (see comment #57 in
the bugzilla).

Rather than extending the blacklist piecemeal, disable async suspend for
all JMicron multi-function SATA/PATA/AHCI devices.

This quirk could stay in the ahci and pata_jmicron drivers, but it's likely
the problem will occur even if pata_jmicron isn't loaded until after the
suspend/resume.  Making it a PCI quirk ensures that we'll preserve the
power-on order even if the drivers aren't loaded.

[bhelgaas: changelog, limit to multi-function, limit to IDE/ATA]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81551Reported-and-tested-by: NBarto <mister.freeman@laposte.net>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.15+

Firmware typically configures the PCIe fabric with a consistent Max Payload
Size setting based on the devices present at boot.  A hot-added device
typically has the power-on default MPS setting (128 bytes), which may not
match the fabric.

The previous Linux default, in the absence of any "pci=pcie_bus_*" options,
was PCIE_BUS_TUNE_OFF, in which we never touch MPS, even for hot-added
devices.

Add a new default setting, PCIE_BUS_DEFAULT, in which we make sure every
device's MPS setting matches the upstream bridge.  This makes it more
likely that a hot-added device will work in a system with optimized MPS
configuration.

Note that if we hot-add a device that only supports 128-byte MPS, it still
likely won't work because we don't reconfigure the rest of the fabric.
Booting with "pci=pcie_bus_peer2peer" is a workaround for this because it
sets MPS to 128 for everything.

[bhelgaas: changelog, new default, rework for pci_configure_device() path]
Tested-by: NKeith Busch <keith.busch@intel.com>
Tested-by: NJordan Hargrave <jharg93@gmail.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>

Meelis and Helge reported that 3a9ad0b4 ("PCI: Add pci_bus_addr_t")
caused HPMCs on A500 and hangs on rp5470.

PA-RISC does not set ARCH_DMA_ADDR_T_64BIT, even for 64-bit kernels, so
prior to 3a9ad0b4, we always used 32-bit PCI addresses.  After
3a9ad0b4, we do use 64-bit PCI addresses in 64-bit kernels, and
apparently there's some PA-RISC problem related to them.

Fixes: 3a9ad0b4 ("PCI: Add pci_bus_addr_t")
Link: http://lkml.kernel.org/r/alpine.LRH.2.11.1507260929000.30065@math.ut.eeReported-by: NMeelis Roos <mroos@linux.ee>
Reported-by: NHelge Deller <deller@gmx.de>
Tested-by: NHelge Deller <deller@gmx.de>
Based-on-idea-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
CC: stable@vger.kernel.org	# v3.19+

Previously we checked for invalid MPS settings, i.e., a device with MPS
different than its upstream bridge, in pcie_bus_detect_mps().  We only did
this if the arch or hotplug driver called pcie_bus_configure_settings(),
and then only if PCIe bus tuning was disabled (PCIE_BUS_TUNE_OFF).

Move the MPS checking code to pci_configure_device(), so we do it in the
pci_device_add() path for every device.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

of_parse_phandle() returns a device_node pointer with the refcount
incremented.  We should dispose of this reference when we're finished.

Drop the reference acquired by of_parse_phandle().
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

The pcibios_msi_controller() hook was only implemented by ARM, and it sets
pci_bus->msi now, so it doesn't need this hook anymore.

Remove the unused pcibios_msi_controller() hook.

[bhelgaas: changelog, split into separate patch]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

ARM previously stored the msi_controller pointer in its sysdata, struct
pci_sys_data, and implemented pcibios_msi_controller() to retrieve it.
That made PCI host controller drivers specific to ARM because they had to
put the msi_controller pointer in the ARM-specific pci_sys_data.

There is now a generic mechanism, pci_scan_root_bus_msi(), for giving the
msi_controller pointer to the PCI core.  Use this for all ARM systems and
for the DesignWare and Xilinx PCI host controller drivers.

This removes an ARM dependency from the DesignWare, DRA7xx, EXYNOS, i.MX6,
Keystone, Layerscape, SPEAr13xx, and Xilinx drivers.

[bhelgaas: changelog, split into separate patch]
Suggested-by: NRussell King <linux@arm.linux.org.uk>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NJingoo Han <jingoohan1@gmail.com>
CC: Pratyush Anand <pratyush.anand@gmail.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Simon Horman <horms@verge.net.au>
CC: Russell King <linux@arm.linux.org.uk>
CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Michal Simek <michal.simek@xilinx.com>
CC: Marc Zyngier <marc.zyngier@arm.com>

Add a pci_scan_root_bus_msi() interface so an arch can specify the MSI
controller up front.  This removes the need for a pcibios callback to set
the MSI controller later.

This is not exported because I'd like to replace the variety of "scan root
bus" interfaces with a single, more extensible interface that can handle
the MSI controller, domain, pci_ops, resources, etc.  I hope this interface
is temporary.

[bhelgaas: changelog, split into separate patch]
Suggested-by: NRussell King <linux@arm.linux.org.uk>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJingoo Han <jingoohan1@gmail.com>

Make pci-host-generic driver (kernel option PCI_HOST_GENERIC) available on
arm64.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

ARM64 requires setup-irq.o to provide pci_fixup_irqs() implementation.  We
are adding this now to support the pci-host-generic host controller, but we
enable it for ARM64 PCI so that other host controllers can use this as
well.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The generic OF-based host controller driver uses pci_common_init_dev(),
which is ARM-specific and requires the ARM struct hw_pci.  The part of
pci_common_init_dev() that is needed is limited and can be done here
without using hw_pci.

Note that the ARM pcibios functions expect the PCI sysdata to be a pointer
to a struct pci_sys_data.  Add a struct pci_sys_data as the first element
in struct gen_pci so that when we use a gen_pci pointer as sysdata, it is
also a pointer to a struct pci_sys_data.

Create and scan the root bus directly without using the ARM
pci_common_init_dev() interface.

[bhelgaas: changelog, move pcie_bus_configure_settings() before
pci_bus_add_devices(), combine !PCI_PROBE_ONLY blocks]
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: NPavel Fedin <p.fedin@samsung.com>
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Simplify a trivial if-return sequence by combining it with a preceding
function call.

The semantic patch that makes this change is available in
scripts/coccinelle/misc/simple_return.cocci.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Lucas Stach <l.stach@pengutronix.de>

Use BUG_ON() instead of an if condition followed by BUG().

The semantic patch that makes this change is available in
scripts/coccinelle/misc/bugon.cocci.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Pratyush Anand <pratyush.anand@gmail.com>

There is no need to use the IS_ERR_VALUE() macro for checking the return
value from pm_runtime_* functions.

Test for a negative pm_runtime_get_sync() return value instead of using
IS_ERR_VALUE().

The semantic patch that makes this change is available in
scripts/coccinelle/api/pm_runtime.cocci.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Kishon Vijay Abraham I <kishon@ti.com>

We should not assume any particular hardware topology.  Commit d0751b98
("PCI: Add dev->has_secondary_link to track downstream PCIe links") relied
on the assumption that every PCIe hierarchy is rooted at a Root Port.  But
we can't rely on any assumption about what hardware we will find; we just
have to deal with the world as it is.

On some platforms, PCIe devices (endpoints, switch upstream ports, etc.)
appear directly on the root bus, and there is no Root Port in the PCI bus
hierarchy.  For example, Meelis observed these top-level devices on a
Sparc V245:

  0000:02:00.0 PCI bridge to [bus 03-0d]    Switch Upstream Port
  0001:02:00.0 PCI bridge to [bus 03]       PCIe to PCI/PCI-X Bridge

These devices *look* like they have links going upstream, but there really
are no upstream devices.

In set_pcie_port_type(), we used the parent device to figure out which side
of a switch port has a link, so if the parent device did not exist, we
dereferenced a NULL parent pointer.

Check whether the parent device exists before dereferencing it.

Meelis observed this oops on Sparc V245 and T2000.  Ben Herrenschmidt says
this is also possible on IBM PowerVM guests on PowerPC.

[bhelgaas: changelog, comment]
Link: http://lkml.kernel.org/r/alpine.LRH.2.20.1508122118210.18637@math.ut.eeReported-by: NMeelis Roos <mroos@linux.ee>
Tested-by: NMeelis Roos <mroos@linux.ee>
Signed-off-by: NYijing Wang <wangyijing@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>

There's a typo in commit e39758e0 in linux-next, which incorrectly
spells "msi_desc_to_pci_sysdata()" as "msi_desc_to_pci_sys_data()" and
causes build failure:

> ../drivers/pci/host/pcie-xilinx.c:235:3: error: implicit declaration
    of function 'msi_desc_to_pci_sys_data' [-Werror=implicit-function-declaration]

Fixes: e39758e0 "PCI: Use helper functions to access fields in struct msi_desc"
Signed-off-by: NJiang Liu <jiang.liu@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mark Brown <broonie@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Cc: Srikanth Thokala <sthokal@xilinx.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Yijing Wang <wangyijing@huawei.com>
Link: http://lkml.kernel.org/r/1439912763-10645-1-git-send-email-jiang.liu@linux.intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Remove pci_ats_enabled().  There are no callers outside the ATS code
itself.  We don't need to check ats_cap, because if we don't find an ATS
capability, we'll never set ats_enabled.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

Stop caching the Invalidate Queue Depth in struct pci_dev.
pci_ats_queue_depth() is typically called only once per device, and it
returns a fixed value per-device, so callers who need the value frequently
can cache it themselves.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

There's no need to BUG() if we enable ATS when it's already enabled.  We
don't need to BUG() when disabling ATS on a device that doesn't support ATS
or if it's already disabled.  If ATS is enabled, certainly we found an ATS
capability in the past, so it should still be there now.

Clean up these error paths.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

Use the pci_physfn() helper rather than looking up physfn by hand.
No functional change.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

The ATS setup code in ats_alloc_one() is only used by pci_ats_init(), so
inline it there.  No functional change.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

We previously returned -ENODEV for devices that don't support ATS (except
that we always returned 0 for VFs, whether or not they support ATS).

For consistency, always return -EINVAL (not -ENODEV) if the device doesn't
support ATS.  Return zero for VFs that support ATS.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

The pci_ats struct is small and will get smaller, so I don't think it's
worth allocating it separately from the pci_dev struct.

Embed the ATS fields directly into struct pci_dev.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

Previously, we allocated pci_ats structures when an IOMMU driver called
pci_enable_ats().  An SR-IOV VF shares the STU setting with its PF, so when
enabling ATS on the VF, we allocated a pci_ats struct for the PF if it
didn't already have one.  We held the sriov->lock to serialize threads
concurrently enabling ATS on several VFS so only one would allocate the PF
pci_ats.

Gregor reported a deadlock here:

  pci_enable_sriov
    sriov_enable
      virtfn_add
        mutex_lock(dev->sriov->lock)      # acquire sriov->lock
        pci_device_add
          device_add
            BUS_NOTIFY_ADD_DEVICE notifier chain
            iommu_bus_notifier
              amd_iommu_add_device        # iommu_ops.add_device
                init_iommu_group
                  iommu_group_get_for_dev
                    iommu_group_add_device
                      __iommu_attach_device
                        amd_iommu_attach_device  # iommu_ops.attach_device
                          attach_device
                            pci_enable_ats
                              mutex_lock(dev->sriov->lock) # deadlock

There's no reason to delay allocating the pci_ats struct, and if we
allocate it for each device at enumeration-time, there's no need for
locking in pci_enable_ats().

Allocate pci_ats struct during enumeration, when we initialize other
capabilities.

Note that this implementation requires ATS to be enabled on the PF first,
before on any of the VFs because the PF controls the STU for all the VFs.

Link: http://permalink.gmane.org/gmane.linux.kernel.iommu/9433Reported-by: NGregor Dick <gdick@solarflare.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>

The PERST# line in am57x-evm is connected to a GPIO line and PERST# should
be driven high to indicate the clocks are stable (As per Figure 2-10: Power
Up of the PCIe CEM spec 3.0).

Add support to make GPIO drive PERST# line.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

DRA7xx requires the MSE bit to be cleared to set the master in standby
mode.  (In DRA7xx TRM_vE, section 24.9.4.5.2.2.1 PCIe Controller Master
Standby Behavior advises to use the clearing of the local MSE bit to set
the master in standby.  Without this some of the clocks do not idle).

Clear the MSE bit on suspend and enable it on resume.  Clearing MSE bit is
required to get clocks to be idled after suspend.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: NSekhar Nori <nsekhar@ti.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NJingoo Han <jingoohan1@gmail.com>