Commit Graph

29 Commits

Author SHA1 Message Date
Stephen Hemminger 3984ca1c6e PCI: Remove unused pci_vpd_truncate()
My philosophy is unused code is dead code.  And dead code is subject to bit
rot and is a likely source of bugs.  Use it or lose it.

This reverts db5679437a ("PCI: add interface to set visible size of
VPD"), removing this interface:

    pci_vpd_truncate()

[bhelgaas: split to separate patch, also remove prototype from pci.h]
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-13 11:14:43 -07:00
Bjorn Helgaas fed2451512 PCI: Remove pcie_cap_has_devctl()
pcie_cap_has_devctl() does nothing, so remove it.  Simplicity over
consistency in this case.  No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-By: Jiang Liu <jiang.liu@huawei.com>
2013-08-28 20:51:39 -06:00
Bjorn Helgaas 6d3a1741f1 PCI: Support PCIe Capability Slot registers only for ports with slots
Previously we allowed callers to access Slot Capabilities, Status, and
Control for Root Ports even if the Root Port did not implement a slot.
This seems dubious because the spec only requires these registers if a
slot is implemented.

It's true that even Root Ports without slots must have *space* for these
slot registers, because the Root Capabilities, Status, and Control
registers are after the slot registers in the capability.  However,
for a v1 PCIe Capability, the *semantics* of the slot registers are
undefined unless a slot is implemented.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-By: Jiang Liu <jiang.liu@huawei.com>
2013-08-28 20:51:39 -06:00
Bjorn Helgaas c8b303d020 PCI: Remove PCIe Capability version checks
Previously we relied on the PCIe r3.0, sec 7.8, spec language that says
"For Functions that do not implement the [Link, Slot, Root] registers,
these spaces must be hardwired to 0b," which means that for v2 PCIe
capabilities, we don't need to check the device type at all.

But it's simpler if we don't need to check the capability version at all,
and I think the spec is explicit enough about which registers are required
for which types that we can remove the version checks.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-By: Jiang Liu <jiang.liu@huawei.com>
2013-08-28 20:51:39 -06:00
Bjorn Helgaas d3694d4fa3 PCI: Allow PCIe Capability link-related register access for switches
Every PCIe device has a link, except Root Complex Integrated Endpoints
and Root Complex Event Collectors.  Previously we didn't give access
to PCIe capability link-related registers for Upstream Ports, Downstream
Ports, and Bridges, so attempts to read PCI_EXP_LNKCTL incorrectly
returned zero.  See PCIe spec r3.0, sec 7.8 and 1.3.2.3.

Reference: http://lkml.kernel.org/r/979A8436335E3744ADCD3A9F2A2B68A52AD136BE@SJEXCHMB10.corp.ad.broadcom.com
Reported-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-By: Jiang Liu <jiang.liu@huawei.com>
2013-08-28 11:28:22 -06:00
Alex Williamson 969daa349f PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS
PCI_EXP_FLAGS_TYPE is a mask, not an offset.  Fix it.

Previously, pcie_capability_read_word(..., PCI_EXP_FLAGS, ...) would
fail.

[bhelgaas:  tweak changelog]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.7+
2013-02-15 11:46:24 -07:00
Myron Stowe 1c531d82ee PCI: Use PCI Express Capability accessor
Use PCI Express Capability access functions to simplify device
Capabilities Register usages.

Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-30 21:24:39 -07:00
Jiang Liu 8c0d3a02c1 PCI: Add accessors for PCI Express Capability
The PCI Express Capability (PCIe spec r3.0, sec 7.8) comes in two
versions, v1 and v2.  In v1 Capability structures (PCIe spec r1.0 and
r1.1), some fields are optional, so the structure size depends on the
device type.

This patch adds functions to access this capability so drivers don't
have to be aware of the differences between v1 and v2.  Note that these
new functions apply only to the "PCI Express Capability," not to any of
the other "PCI Express Extended Capabilities" (AER, VC, ACS, MFVC, etc.)

Function pcie_capability_read_word/dword() reads the PCIe Capabilities
register and returns the value in the reference parameter "val".  If
the PCIe Capabilities register is not implemented on the PCIe device,
"val" is set to 0.

Function pcie_capability_write_word/dword() writes the value to the
specified PCIe Capability register.

Function pcie_capability_clear_and_set_word/dword() sets and/or clears bits
of a PCIe Capability register.

[bhelgaas: changelog, drop "pci_" prefixes, don't export
pcie_capability_reg_implemented()]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-08-23 09:41:20 -06:00
Alex Williamson c63587d7f5 PCI: export pci_user functions for use by other drivers
VFIO PCI support will make use of these for user-initiated
PCI config accesses.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-06-12 09:21:42 -06:00
Jan Kiszka a2e27787f8 PCI: Introduce INTx check & mask API
These new PCI services allow to probe for 2.3-compliant INTx masking
support and then use the feature from PCI interrupt handlers. The
services are properly synchronized with concurrent config space access
via sysfs or on device reset.

This enables generic PCI device drivers like uio_pci_generic or KVM's
device assignment to implement the necessary kernel-side IRQ handling
without any knowledge about device-specific interrupt status and control
registers.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-01-06 12:10:34 -08:00
Jan Kiszka fb51ccbf21 PCI: Rework config space blocking services
pci_block_user_cfg_access was designed for the use case that a single
context, the IPR driver, temporarily delays user space accesses to the
config space via sysfs. This assumption became invalid by the time
pci_dev_reset was added as locking instance. Today, if you run two loops
in parallel that reset the same device via sysfs, you end up with a
kernel BUG as pci_block_user_cfg_access detect the broken assumption.

This reworks the pci_block_user_cfg_access to a sleeping service
pci_cfg_access_lock and an atomic-compatible variant called
pci_cfg_access_trylock. The former not only blocks user space access as
before but also waits if access was already locked. The latter service
just returns false in this case, allowing the caller to resolve the
conflict instead of raising a BUG.

Adaptions of the ipr driver were originally written by Brian King.

Acked-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-01-06 12:10:33 -08:00
Greg Thelen 34e3207205 PCI: handle positive error codes
Callers expect pci_user_{read,write}_config_*() to indicate errors by
returning negative values.  Prior to this change, the indicated routines
could return positive error codes (e.g. PCIBIOS_BAD_REGISTER_NUMBER)
which callers would mistakenly interpret as success.

This change converts any non-zero return from the mentioned routines
into unambiguous negative value return codes.

Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-05-10 15:43:36 -07:00
Greg Thelen d97ecd8191 PCI: check pci_vpd_pci22_wait() return
pci_vpd_pci22_write() calls pci_vpd_pci22_wait() after writing
PCI_VPD_DATA and PCI_VPD_ADDR to wait for the VPD operation to complete.
The result pci_vpd_pci22_wait() was not checked for error.

This change checks for error.

Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-05-10 15:43:35 -07:00
Prarit Bhargava 5030718ee4 PCI: output FW warning in pci_read/write_vpd
pci_read/write_vpd() can fail due to a timeout.  Usually the command
times out because of firmware issues (incorrect vpd length, etc.) on the
PCI card.  Currently, the timeout occurs silently.

Output a message to the user indicating that they should check with
their vendor for new firmware.

Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-05-18 15:00:25 -07:00
Thomas Gleixner 511dd98ce8 PCI: Convert pci_lock to raw_spinlock
pci_lock must be a real spinlock in preempt-rt. Convert it to
raw_spinlock. No change for !RT kernels.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-05-11 12:01:09 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Huang Ying a72b46c384 PCI: Add pci_bus_set_ops
pci_bus_set_ops changes pci_ops associated with a pci_bus. This can be
used by debug tools such as PCIE AER error injection to fake some PCI
configuration registers.

Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:29:33 -07:00
Randy Dunlap cffb2fafb7 docbooks: add/fix PCI kernel-doc
Add drivers/pci/*.c source files to DocBook/kernel-api.tmpl
and update those pci/*.c source files that need kernel-doc fixes.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-04-22 14:49:33 -07:00
Anton Vorontsov d407e32efe PCI: Fix oops in pci_vpd_truncate
pci_vpd_truncate() should check for dev->vpd->attr, otherwise this might
happen:

  sky2 driver version 1.22
  Unable to handle kernel paging request for data at address 0x0000000c
  Faulting instruction address: 0xc01836fc
  Oops: Kernel access of bad area, sig: 11 [#1]
  [...]
  NIP [c01836fc] pci_vpd_truncate+0x38/0x40
  LR [c029be18] sky2_probe+0x14c/0x518
  Call Trace:
  [ef82bde0] [c029bda4] sky2_probe+0xd8/0x518 (unreliable)
  [ef82be20] [c018a11c] local_pci_probe+0x24/0x34
  [ef82be30] [c018a14c] pci_call_probe+0x20/0x30
  [ef82be50] [c018a330] __pci_device_probe+0x64/0x78
  [ef82be60] [c018a44c] pci_device_probe+0x30/0x58
  [ef82be80] [c01aa270] really_probe+0x78/0x1a0
  [ef82bea0] [c01aa460] __driver_attach+0xa4/0xa8
  [ef82bec0] [c01a96ac] bus_for_each_dev+0x60/0x9c
  [ef82bef0] [c01aa0b4] driver_attach+0x24/0x34
  [ef82bf00] [c01a9e08] bus_add_driver+0x12c/0x1cc
  [ef82bf20] [c01aa87c] driver_register+0x6c/0x110
  [ef82bf30] [c018a770] __pci_register_driver+0x4c/0x9c
  [ef82bf50] [c03782c8] sky2_init_module+0x30/0x40
  [ef82bf60] [c0001dbc] do_one_initcall+0x34/0x1a0
  [ef82bfd0] [c0362240] do_initcalls+0x38/0x58

This happens with CONFIG_SKY2=y, and "ip=on" kernel command line, so
pci_vpd_truncate() is called before late_initcall(pci_sysfs_init),
therefore ->attr isn't yet initialized.

Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:05:38 -07:00
Stephen Hemminger db5679437a PCI: add interface to set visible size of VPD
The VPD on all devices may not be 32K. Unfortunately, there is no
generic way to find the size, so this adds a simple API hook
to reset it.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:18 -08:00
Stephen Hemminger 287d19ce2e PCI: revise VPD access interface
Change PCI VPD API which was only used by sysfs to something usable
in drivers.
   * move iteration over multiple words to the low level
   * use conventional types for arguments
   * add exportable wrapper

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:17 -08:00
Stephen Hemminger 1120f8b816 PCI: handle long delays in VPD access
Accessing the VPD area can take a long time.  The existing
VPD access code fails consistently on my hardware. There are comments
in the SysKonnect vendor driver that it can take up to 13ms per word.

Change the access routines to:
  * use a mutex rather than spinning with IRQ's disabled and lock held
  * have a much longer timeout
  * call cond_resched while spinning

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:16 -08:00
Benjamin Li 99cb233d60 PCI: Limit VPD read/write lengths for Broadcom 5706, 5708, 5709 rev.
For Broadcom 5706, 5708, 5709 rev. A nics, any read beyond the
VPD end tag will hang the device.  This problem was initially
observed when a vpd entry was created in sysfs
('/sys/bus/pci/devices/<id>/vpd').   A read to this sysfs entry
will dump 32k of data.  Reading a full 32k will cause an access
beyond the VPD end tag causing the device to hang.  Once the device
is hung, the bnx2 driver will not be able to reset the device.
We believe that it is legal to read beyond the end tag and
therefore the solution is to limit the read/write length.

A majority of this patch is from Matthew Wilcox who gave code for
reworking the PCI vpd size information.  A PCI quirk added for the
Broadcom NIC's to limit the read/write's.

Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-07-02 11:25:54 -07:00
Ben Hutchings 94e6108803 PCI: Expose PCI VPD through sysfs
Vital Product Data (VPD) may be exposed by PCI devices in several
ways.  It is generally unsafe to read this information through the
existing interfaces to user-land because of stateful interfaces.

This adds:
- abstract operations for VPD access (struct pci_vpd_ops)
- VPD state information in struct pci_dev (struct pci_vpd)
- an implementation of the VPD access method specified in PCI 2.2
  (in access.c)
- a 'vpd' binary file in sysfs directories for PCI devices with VPD
  operations defined

It adds a probe for PCI 2.2 VPD in pci_scan_device() and release of
VPD state in pci_release_dev().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-20 21:47:07 -07:00
Al Viro f6a570333e [PATCH] severing module.h->sched.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-12-04 02:00:22 -05:00
Matthew Wilcox 7ea7e98fd8 PCI: Block on access to temporarily unavailable pci device
The existing implementation of pci_block_user_cfg_access() was recently
criticised for providing out of date information and for returning errors
on write, which applications won't be expecting.

This reimplementation uses a global wait queue and a bit per device.
I've open-coded prepare_to_wait() / finish_wait() as I could optimise
it significantly by knowing that the pci_lock protected us at all points.

It looked a bit funny to be doing a spin_unlock_irqsave(); schedule(),
so I used spin_lock_irq() for the _user versions of pci_read_config and
pci_write_config.  Not carrying a flags pointer around made the code
much less nasty.

Attempts to block an already blocked device hit a BUG() and attempts to
unblock an already unblocked device hit a WARN().  If we need to block
access to a device from userspace, it's because it's unsafe for even
another bit of the kernel to access the device.  An attempt to block
a device for a second time means we're about to access the device to
perform some other operation, which could provoke undefined behaviour
from the device.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Acked-by: Adam Belay <abelay@novell.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:36:58 -08:00
Adrian Bunk 48b1914873 [PATCH] PCI: drivers/pci/: small cleanups
This patch contains the following cleanups:
- access.c should #include "pci.h" for getting the prototypes of it's
  global functions
- hotplug/shpchp_pci.c: make the needlessly global function
  program_fw_provided_values() static

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-10 16:09:18 -08:00
Brian King e04b0ea2e0 [PATCH] PCI: Block config access during BIST
Some PCI adapters (eg.  ipr scsi adapters) have an exposure today in that they
issue BIST to the adapter to reset the card.  If, during the time it takes to
complete BIST, userspace attempts to access PCI config space, the host bus
bridge will master abort the access since the ipr adapter does not respond on
the PCI bus for a brief period of time when running BIST.  On PPC64 hardware,
this master abort results in the host PCI bridge isolating that PCI device
from the rest of the system, making the device unusable until Linux is
rebooted.  This patch is an attempt to close that exposure by introducing some
blocking code in the PCI code.  When blocked, writes will be humored and reads
will return the cached value.  Ben Herrenschmidt has also mentioned that he
plans to use this in PPC power management.

Signed-off-by: Brian King <brking@us.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/pci/access.c    |   89 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/pci/pci-sysfs.c |   20 +++++-----
 drivers/pci/pci.h       |    7 +++
 drivers/pci/proc.c      |   28 +++++++--------
 drivers/pci/syscall.c   |   14 +++----
 include/linux/pci.h     |    7 +++
 6 files changed, 134 insertions(+), 31 deletions(-)
2005-10-28 15:36:58 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00