Add pcie_bandwidth_available() to compute the bandwidth available to a
device.  This may be limited by the device itself or by a slower upstream
link leading to the device.

The available bandwidth at each link along the path is computed as:

  link_width * link_speed * (1 - encoding_overhead)

2.5 and 5.0 GT/s links use 8b/10b encoding, which reduces the raw bandwidth
available by 20%; 8.0 GT/s and faster links use 128b/130b encoding, which
reduces it by about 1.5%.

The result is in Mb/s, i.e., megabits/second, of raw bandwidth.

Also return the device with the slowest link and the speed and width of
that link.
Signed-off-by: NTal Gilboa <talgi@mellanox.com>
[bhelgaas: changelog, leave pcie_get_minimum_link() alone for now, return
bw directly, use pci_upstream_bridge(), check "next_bw <= bw" to find
uppermost limiting device, return speed/width of the limiting device]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Add pcie_bandwidth_capable() to compute the max link bandwidth supported by
a device, based on the max link speed and width, adjusted by the encoding
overhead.

The maximum bandwidth of the link is computed as:

  max_link_width * max_link_speed * (1 - encoding_overhead)

2.5 and 5.0 GT/s links use 8b/10b encoding, which reduces the raw bandwidth
available by 20%; 8.0 GT/s and faster links use 128b/130b encoding, which
reduces it by about 1.5%.

The result is in Mb/s, i.e., megabits/second, of raw bandwidth.
Signed-off-by: NTal Gilboa <talgi@mellanox.com>
[bhelgaas: add 16 GT/s, adjust for pcie_get_speed_cap() and
pcie_get_width_cap() signatures, don't export outside drivers/pci]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Add pcie_get_width_cap() to find the max link width supported by a device.
Change max_link_width_show() to use pcie_get_width_cap().
Signed-off-by: NTal Gilboa <talgi@mellanox.com>
[bhelgaas: return width directly instead of error and *width, don't export
outside drivers/pci]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NTariq Toukan <tariqt@mellanox.com>

Add pcie_get_speed_cap() to find the max link speed supported by a device.
Change max_link_speed_show() to use pcie_get_speed_cap().
Signed-off-by: NTal Gilboa <talgi@mellanox.com>
[bhelgaas: return speed directly instead of error and *speed, don't export
outside drivers/pci]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NTariq Toukan <tariqt@mellanox.com>

PCIe 4.0 defines the 16.0 GT/s link speed.  Links can run at that speed
without any Linux changes, but previously their sysfs "max_link_speed" and
"current_link_speed" files contained "Unknown speed", not the expected
"16.0 GT/s".

Add decoding for the new 16 GT/s link speed.
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
[bhelgaas: add PCI_EXP_LNKCAP2_SLS_16_0GB]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NDongdong Liu <liudongdong3@huawei.com>

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

acpi_get_object_info() is intended for early probe usage and as such should
not call any methods which may rely on OpRegions, but it used to also call
_STA to get the status, which on some systems does rely on OpRegions, this
behavior and the acpi_device_info.current_status member are being removed.

This commit prepares the acpiphp_ibm code for this by having it get the
status itself using acpi_bus_get_status_handle(). Note no error handling is
necessary on any errors acpi_bus_get_status_handle() leaves the value of
the passed in current_status at its 0 initialization value.
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch adds support to the Cadence PCIe controller in endpoint mode.

Since pieces of source code are shared with the host driver (Root
Complex mode), we create a new directory under drivers/pci dedicated to
the Cadence PCIe controller. The common code is placed into
drivers/pci/cadence/pcie-cadence.c and used by both the host and
endpoint controller drivers.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Fix the pci_epf_make() function so it can now bind many EPF devices to the
same EPF driver.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This patch updates the prototype of most handlers from 'struct
pci_epc_ops' so the EPC library can now support multi-function devices.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This patch adds support to the Cadence PCIe controller in host mode.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This patchs moves generic source code from
drivers/pci/host/pci-host-common.c into drivers/pci/probe.c.

Indeed the extracted lines of code were duplicated by many host
controller drivers. Regrouping them into a generic function gives a
change to properly share this code without introducing a useless
dependency to PCI_HOST_COMMON, which selects PCI_ECAM when not needed by
most host controller drivers.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Call pci_free_resource_list() from pci_host_common_probe() when probing
fails, as done inside gen_pci_init() when this later function fails.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

The patch moves the gen_pci_parse_request_of_pci_ranges() function from
drivers/pci/host/pci-host-common.c into drivers/pci/of.c to easily share
common source code between PCI host drivers.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Clean up drivers/Makefile by moving the pci/endpoint and pci/dwc entries
from drivers/Makefile into drivers/pci/Makefile.

Since we don't want to introduce any dependency between CONFIG_PCI and
CONFIG_PCI_ENDPOINT, we now always execute drivers/pci/Makefile.

Hence all Makefiles in drivers/pci/ were updated accordingly so no file is
compiled when CONFIG_PCI is not defined.

Also, we add a comment to reinforce that EPC and EPF libraries must be
initialized before their users. Hence built-in EPC drivers, such as
those of Designware, are linked after the endpoint core libraries.

Finally, we add another comment to explain why obj-y has been chosen
instead of obj-$(CONFIG_PCIE_DW) to parse the dwc/ sub-folder.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Add definitions for DPC Status register fields and use them in the code.
No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

dpc_process_rp_pio_error() only calls dpc_rp_pio_get_info(), so squash them
together.  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

We read and immediately print the RP PIO log registers.  We don't save
them, so there's no need to define structs for them.  Remove the structs
and read the registers into local variables instead.  No functional change
intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

Move the dpc->rp_pio_status assignment into dpc_rp_pio_get_info() since
that's where we read rp_pio->status anway.  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

Separating dpc_rp_pio_print_error() doesn't really provide any useful
abstraction, so squash it into its caller, dpc_rp_pio_get_info().  No
functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

In dpc_probe(), we set dpc->rp_log_size to zero if we think the hardware
reports an invalid size.  In this case, we could have dpc->rp_extensions
set but dpc->rp_log_size == 0, and we should print the basic RP PIO
registers but not the variable-size portion.  We already checked for
dpc->rp_log_size < 4 above, so this patch is just for consistency of style.
No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

In dpc_rp_pio_get_info() rename the local "status" variable to
"dpc_status".  This is to make room for another variable named "status" in
a subsequent patch.  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

Separating dpc_rp_pio_print_tlp_header() doesn't really provide any useful
abstraction, so squash it into its caller, dpc_rp_pio_print_error().  No
functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

The RP PIO registers (status, mask, severity, etc) are only implemented if
the "RP Extensions for DPC" bit is set in the DPC Capabilities register.

Previously we called dpc_process_rp_pio_error(), which reads and decodes
those RP PIO registers, whenever the DPC Status register indicated an "RP
PIO error" (Trigger Reason == 3 and Trigger Reason Extension == 0).

It does seem reasonable to assume that DPC Status would only indicate an RP
PIO error if the RP extensions are supported, but PCIe r4.0, sec 7.9.15.4,
is actually not explicit about that: it does not say "Trigger Reason
Extension == 0 is valid only for Root Ports that support RP Extensions for
DPC."

Check whether the RP Extensions for DPC are supported before trying to read
the RP PIO registers.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

The RP PIO Log Size is a read-only field in the DPC Capability, so it is
constant and known at probe-time, but previously we read it every time we
processed an RP PIO error.

Read it once in dpc_probe() (if the RP Extensions for DPC are supported)
and remember the size in struct dpc_dev.  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

"rp" is ambiguous: it might mean "this DPC device is a Root Port."  But in
fact, it means "this DPC device is a Root Port *and* it supports a set of
DPC Extensions."

Rename "rp" to "rp_extensions" to make this more clear.  No functional
change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

Add a local variable for DPC capability offset and replace repeated use of
"dpc->cap_pos" with simply "cap".  No functional change intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

7441b062 ("s390/pci: PCI hotplug support via SCLP") added
s390_pci_hpc.c, which included this license information:

  +MODULE_LICENSE("GPL");

Based on "git show 7441b062:include/linux/module.h", that "GPL" string
means "GPL v2 or later":

   *      "GPL"                           [GNU Public License v2 or later]

0729dcf2 ("s390: hotplug: make pci_hpc explicitly non-modular")
subsequently replaced the MODULE_LICENSE() with a "License: GPL" comment.

Add SPDX GPL-2.0+ and remove the "License: GPL" comment, relying on the
assertion in b2441318 ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") that the SPDX identifier may be used
instead of the full boilerplate text.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NSebastian Ott <sebott@linux.vnet.ibm.com>

Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed
either GPL version 2 or any later version.

Remove the boilerplate GPL version 2 or later language, relying on the
assertion in b2441318 ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") that the SPDX identifier may be used
instead of the full boilerplate text.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add SPDX GPL-2.0 to all PCI files that referred to the kernel default
"COPYING" file, which specifies GPL version 2.

Remove the boilerplate language referring to the GPL and "COPYING", relying
on the assertion in b2441318 ("License cleanup: add SPDX GPL-2.0
license identifier to files with no license") that the SPDX identifier may
be used instead of the full boilerplate text.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add SPDX GPL-2.0 to all PCI files that specified the GPL version 2 license.

Remove the boilerplate GPL version 2 language, relying on the assertion in
b2441318 ("License cleanup: add SPDX GPL-2.0 license identifier to
files with no license") that the SPDX identifier may be used instead of the
full boilerplate text.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Devices can go offline when erors reported. This patch adds a change
to the kernel object and lets udev know of error. When device resumes,
a change is also set reporting device as online. Therefore, EEH and
AER events are better propagated to user space for PCI devices in all
arches.
Signed-off-by: NBryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: NJuan J. Alvarez <jjalvare@linux.vnet.ibm.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Rename interrupt_event_handler() to dpc_work() so there's more useful
information in stack traces and similar situations.  No functional change
intended.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSinan Kaya <okaya@codeaurora.org>

The interrupt message number is the first 5 bits, but the driver was
masking only the first 4 bits.  Fix that by using the existing
define.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
[bhelgaas: remove reformatting (done by another patch)]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The "Determination of DPC Control" implementation note in PCIe r4.0, sec
6.1.10, recommends the operating system always link DPC control to the
control of AER, as the two functionalities are strongly connected.

To avoid conflicts over whether platform firmware or the OS controls DPC,
enable DPC only if AER is enabled in the OS, and the device's error
handling does not have firmware-first AER handling.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NBjorn Helgaas <helgaas@kernel.org>

b2441318 ("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: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now that the DT PCI code is merged into drivers/pci, of_irq_parse_pci() can
be static.
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Frank Rowand <frowand.list@gmail.com>

The Atomic Operations feature (PCIe r4.0, sec 6.15) allows atomic
transctions to be requested by, routed through and completed by PCIe
components. Routing and completion do not require software support.
Component support for each is detectable via the DEVCAP2 register.

A Requester may use AtomicOps only if its PCI_EXP_DEVCTL2_ATOMIC_REQ is
set. This should be set only if the Completer and all intermediate routing
elements support AtomicOps.

A concrete example is the AMD Fiji-class GPU (which is capable of making
AtomicOp requests), below a PLX 8747 switch (advertising AtomicOp routing)
with a Haswell host bridge (advertising AtomicOp completion support).

Add pci_enable_atomic_ops_to_root() for per-device control over AtomicOp
requests. This checks to be sure the Root Port supports completion of the
desired AtomicOp sizes and the path to the Root Port supports routing the
AtomicOps.
Signed-off-by: NJay Cornwall <Jay.Cornwall@amd.com>
Signed-off-by: NFelix Kuehling <Felix.Kuehling@amd.com>
[bhelgaas: changelog, comments, whitespace]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Some multifunction PCI devices with more than 8 functions use "alternative
routing-ID interpretation" (ARI), which means the 8-bit device/function
number field will be interpreted as 8 bits specifying the function number
(the device number is 0 implicitly), rather than the upper 5 bits
specifying the device number and the lower 3 bits specifying the function
number. The kernel can enable and use this.

Expose in a sysfs attribute whether the kernel has enabled ARI, so that a
program in userspace won't have to parse PCI devices and PCI configuration
space to figure out if it is enabled. This will allow better predictable
network naming using PCI function numbers without using PCI bus or device
numbers, which is desirable because bus and device numbers can change with
system configuration but function numbers will not.
Signed-off-by: NStuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Certain Thunderbolt 1 controllers claim to support Command Completed events
(value of 0b in the No Command Completed Support field of the Slot
Capabilities register) but in reality they neither set the Command
Completed bit in the Slot Status register nor signal a Command Completed
interrupt:

  8086:1513  CV82524  [Light Ridge 4C  2010]
  8086:151a  DSL2310  [Eagle Ridge 2C  2011]
  8086:151b  CVL2510  [Light Peak 2C   2010]
  8086:1547  DSL3510  [Cactus Ridge 4C 2012]
  8086:1548  DSL3310  [Cactus Ridge 2C 2012]
  8086:1549  DSL2210  [Port Ridge 1C   2011]

All known newer chips (Redwood Ridge and onwards) set No Command Completed
Support, indicating that they do not support Command Completed events.

The user-visible impact is that after unplugging such a device, 2 seconds
elapse until pciehp is unbound.  That's because on ->remove,
pcie_write_cmd() is called via pcie_disable_notification() and every call
to pcie_write_cmd() takes 2 seconds (1 second for each invocation of
pcie_wait_cmd()):

  [  337.942727] pciehp 0000:0a:00.0:pcie204: Timeout on hotplug command 0x1038 (issued 21176 msec ago)
  [  340.014735] pciehp 0000:0a:00.0:pcie204: Timeout on hotplug command 0x0000 (issued 2072 msec ago)

That by itself has always been unpleasant, but the situation has become
worse with commit cc27b735 ("PCI/portdrv: Turn off PCIe services during
shutdown"):  Now pciehp is unbound on ->shutdown.  Because Thunderbolt
controllers typically have 4 hotplug ports, every reboot and shutdown is
now delayed by 8 seconds, plus another 2 seconds for every attached
Thunderbolt 1 device.

Thunderbolt hotplug slots are not physical slots that one inserts cards
into, but rather logical hotplug slots implemented in silicon.  Devices
appear beyond those logical slots once a PCI tunnel is established on top
of the Thunderbolt Converged I/O switch.  One would expect commands written
to the Slot Control register to be executed immediately by the silicon, so
for simplicity we always assume NoCompl+ for Thunderbolt ports.

Fixes: cc27b735 ("PCI/portdrv: Turn off PCIe services during shutdown")
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org	# v4.12+
Cc: Sinan Kaya <okaya@codeaurora.org>
Cc: Yehezkel Bernat <yehezkel.bernat@intel.com>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: Andreas Noever <andreas.noever@gmail.com>