Myron Stowe [Fri, 2 Mar 2012 19:45:01 +0000 (12:45 -0700)]
x86/PCI: add spinlock held check to 'pcibios_fwaddrmap_lookup()'
'pcibios_fwaddrmap_lookup()' is used to maintain FW-assigned BIOS BAR
values for reinstatement when normal resource assignment attempts
fail and must be called with the 'pcibios_fwaddrmap_lock' spinlock
held.
This patch adds a WARN_ON notification if the spinlock is not currently
held by the caller.
PCI / PCIe: Introduce command line option to disable ARI
There are PCIe devices on the market that report ARI support but
then fail to initialize correctly when ARI is actually used. This
leads to situations in which kernels 2.6.34 and newer fail to handle
systems where the previous kernels worked without any apparent
problems. Unfortunately, it is currently unknown how many such
devices are there.
For this reason, introduce a new kernel command line option,
pci=noari, allowing users to disable PCIe ARI altogether if they
see problems with PCIe device initialization.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 24 Feb 2012 07:46:49 +0000 (23:46 -0800)]
PCI: Add class support in quirk handling
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: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 24 Feb 2012 03:23:32 +0000 (19:23 -0800)]
PCI: add a PCI resource reallocation config option
Add a new config option, PCI_REALLOC_ENABLE_AUTO, which will
automatically try to re-allocate PCI resources if PCI_IOV support is
enabled and the SR-IOV resources are unassigned. Behavior can still be
controlled using the pci=realloc= parameter.
-v2: According to Jesse, adding one CONFIG option for distribution to
disable it or enable it.
-v3: update Kconfig text (jbarnes)
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 24 Feb 2012 03:23:30 +0000 (19:23 -0800)]
PCI: prepare pci=realloc for multiple options
Let the user could enable and disable with pci=realloc=on or pci=realloc=off
Also
1. move variable and functions near the place they are used.
2. change macro to function
3. change related functions and variable to static and _init
4. update parameter description accordingly.
This will let us add a config option to control default behavior, and
still allow the user to turn off automatic reallocation if it fails on
their platform until a permanent solution is found.
-v2: still honor pci=realloc, and treat it as pci=realloc=on
also use enum instead of ...
-v3: update kernel-paramenters.txt according to Jesse.
Yinghai Lu [Fri, 24 Feb 2012 03:23:29 +0000 (19:23 -0800)]
PCI: Retry on IORESOURCE_IO type allocations
When enabling pci reallocation for a pci bridge, we clear the small size
in in bridge and re-assign with requested + optional size for first
several tries, but Ram mention could have problem with one case:
https://bugzilla.kernel.org/show_bug.cgi?id=15960
After checking the booting log in
https://lkml.org/lkml/2010/4/19/44
[regression, bisected] Xonar DX invalid PCI I/O range since 977d17bb174
We should not stop too early for io ports.
Apr 19 10:19:38 [kernel] pci 0000:04:00.0: BAR 7: can't assign io (size 0x4000)
Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 8: assigned [mem 0x80400000-0x805fffff]
Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 7: can't assign io (size 0x2000)
Apr 19 10:19:38 [kernel] pci 0000:05:02.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:05:03.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:08:00.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:09:04.0: BAR 0: can't assign io (size 0x100)
and clear 00:1c.0 to retry again.
This patch removes IORESOUCE_IO checking, and tries one more time. It
gives us a chance to get an allocation for the 00:1c.0 io port range
because the range from 0x4000 to 0x8000 will be freed and we can use it.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:04 +0000 (20:19 -0700)]
sparc/PCI: get rid of device resource fixups
Tell the PCI core about host bridge address translation so it can take
care of bus-to-resource conversion for us.
N.B. Leon apparently never uses initial BAR values, so it didn't matter
that we never fixed up the I/O resources from bus address to CPU addresses.
Other sparc uses pci_of_scan_bus(), which sets device resources directly
to CPU addresses, not bus addresses, so it didn't need pcibios_fixup_bus()
either. But by telling the core about the offsets, we can nuke
pcibios_resource_to_bus().
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:02 +0000 (20:19 -0700)]
mips/PCI: get rid of device resource fixups
Tell the PCI core about host bridge address translation so it can take
care of bus-to-resource conversion for us.
Here's the wrinkle on Cobalt: we can't generate normal I/O port addresses
on PCI because the GT-64111 doesn't do any address translation, so we have
this:
CPU I/O port addresses [io 0x0000-0xffffff]
PCI bus I/O port addresses [io 0x10000000-0x10ffffff]
Legacy-mode IDE controllers start out with the legacy bus addresses, e.g.,
0x1f0, assigned by pci_setup_device(). These are outside the range of
addresses GT-64111 can generate on PCI, but pcibios_fixup_device_resources()
converted them to CPU addresses anyway by adding io_offset. Therefore, we
had to pre-adjust them in cobalt_legacy_ide_fixup().
With io_offset = 0xf0000000, we had this:
res->start = 0x1f0 initialized in pci_setup_device()
res->start = 0x100001f0 -= io_offset in cobalt_legacy_ide_fixup()
res->start = 0x1f0 += io_offset in pcibios_fixup_device_resources()
The difference after this patch is that the generic pci_bus_to_resource()
only adds the offset if the bus address is inside a host bridge window.
Since 0x1f0 is not a valid bus address and is not inside any windows, it is
unaffected, so we now have this:
region->start = 0x1f0 initialized in pci_setup_device()
res->start = 0x1f0 no offset by pci_bus_to_resource()
That means we can remove both pcibios_fixup_device_resources() and
cobalt_legacy_ide_fixup().
I would *rather* set the host bridge offset to zero (which corresponds
to what the GT-64111 actually does), and have both CPU and PCI addresses
of [io 0x10000000-0x10ffffff]. However, that would require changes to
generic code that assumes legacy I/O addresses, such as pic1_io_resource
([io 0x0020-0x00021]), and we'd have to keep a Cobalt IDE fixup.
Of course, none of this changes the fact that references to I/O port
0x1f0 actually go to port 0x100001f0, not 0x1f0, on the Cobalt PCI bus.
Fortunately the VT82C586 IDE controller only decodes the low 24 address
bits, so it does work.
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:01 +0000 (20:19 -0700)]
ia64/PCI: SN: convert to pci_scan_root_bus() for correct root bus resources
Convert from pci_scan_bus() to pci_scan_root_bus(). Supply the root
bus resources from bussoft. When we move the resource adjustment from
pcibios_fixup_resources() to the PCI core, it will be important to have
the root bus resources correct from the beginning.
CC: Tony Luck <tony.luck@intel.com> CC: Jack Steiner <steiner@sgi.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:00 +0000 (20:19 -0700)]
PCI: add generic pcibios_resource_to_bus()
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.
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:00 +0000 (20:19 -0700)]
PCI: convert bus addresses to resource when reading BARs
Some PCI host bridges translate CPU addresses to PCI bus addresses.
Previously, we initialized pci_dev resources with PCI bus addresses,
then converted them to CPU addresses later in arch-specific code
(pcibios_fixup_resources()), which leaves a window of time where the
pci_dev resources are incorrect.
This patch adds support in the core for this address translation.
When the arch creates the root bus, it can supply the host bridge
address translation information, and the core can use it to set the
pci_dev resources correctly from the beginning.
This gives us a way to fix the problem that quirks that run between device
discovery and pcibios_fixup_resources() fail because they use pci_dev
resources that haven't been converted. The reference below is to one
such problem that affected ARM and ia64.
Note that this patch has no effect until an arch starts using
pci_add_resource_offset() with a non-zero offset: before that, all
all host bridge windows have a zero offset and pci_bus_to_resource()
copies the pci_bus_region directly to the struct resource.
Bjorn Helgaas [Fri, 24 Feb 2012 03:19:00 +0000 (20:19 -0700)]
PCI: add struct pci_host_bridge_window with CPU/bus address offset
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:
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:59 +0000 (20:18 -0700)]
PCI: don't publish new root bus until it's fully initialized
When pci_create_root_bus() adds the new struct pci_bus to the global
pci_root_buses list, the bus becomes visible to other parts of the
kernel, so it should be fully initialized.
This patch delays adding the bus to the pci_root_buses list until after
all the struct pci_bus initialization is finished.
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:58 +0000 (20:18 -0700)]
powerpc/PCI: replace pci_probe_only with pci_flags
We already use pci_flags, so this just sets pci_flags directly and removes
the intermediate step of figuring out pci_probe_only, then using it to set
pci_flags.
The PCI core provides a pci_flags definition (currently __weak), so drop
the powerpc definitions in favor of that.
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: linuxppc-dev@lists.ozlabs.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:58 +0000 (20:18 -0700)]
powerpc/PCI: make pci_probe_only default to 0
pci_probe_only is set on ppc64 to prevent resource re-allocation
by the core. It's meant to be used in very specific circumstances
such as when operating under a hypervisor that may prevent such
re-allocation.
Instead of default to 1, we make it default to 0 and explicitly
set it in the few cases where we need it.
This fixes FSL PCI which wants it clear among others.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We never assign anything other than PCI_ASSIGN_ALL_BUSSES to pci_probe,
so just remove the indirection. If configurability is required in the
future, please use the pci_flags/PCI_REASSIGN_ALL_BUS functionality
as is done for powerpc.
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:57 +0000 (20:18 -0700)]
mips/PCI: replace pci_probe_only with pci_flags
Some architectures (alpha, mips, powerpc) have an arch-specific
"pci_probe_only" flag. Others use PCI_PROBE_ONLY in pci_flags for
the same purpose. This moves mips to the pci_flags approach so
generic code can use the same test across all architectures.
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:57 +0000 (20:18 -0700)]
microblaze/PCI: remove unused pci_flags
pci_flags is initialized to zero and never modified (I think this was just
copied from powerpc). Therefore, "(pci_flags & XX)" is always false and
"!(pci_flags & XX)" is always true, and we can remove all references
to pci_flags.
CC: Michal Simek <monstr@monstr.eu> CC: microblaze-uclinux@itee.uq.edu.au Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:56 +0000 (20:18 -0700)]
arm/PCI: remove arch pci_flags definition
The PCI core provides a pci_flags definition (currently __weak), so drop
the arm definition in favor of that.
We EXPORT_SYMBOL(pci_flags) as arm did previously. I'm dubious about
this: no other architecture exports it, and I didn't see any modules in
the tree that reference it.
CC: Rob Herring <rob.herring@calxeda.com> CC: Russell King <linux@arm.linux.org.uk> CC: linux-arm-kernel@lists.infradead.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Bjorn Helgaas [Fri, 24 Feb 2012 03:18:56 +0000 (20:18 -0700)]
alpha/PCI: replace pci_probe_only with pci_flags
Some architectures (alpha, mips, powerpc) have an arch-specific
"pci_probe_only" flag. Others use PCI_PROBE_ONLY in pci_flags for
the same purpose. This moves alpha to the pci_flags approach so
generic code can use the same test across all architectures.
Bjorn Helgaas [Thu, 23 Feb 2012 21:29:23 +0000 (14:29 -0700)]
PCI: make pci_flags always available
If we move resource assignment functions into the core, we'll still
need a way for architectures to prevent reassignment, e.g., the
"pci_probe_only" functionality, and we'll need a generic, always
available way the core can test for that. The "pci_flags"
arrangement used by several architectures seems like a convenient
way to do this.
Alan Cox [Mon, 13 Feb 2012 12:59:37 +0000 (12:59 +0000)]
x86/mrst/pci: avoid SoC fixups on non-SoC platforms
The PCI fixups get executed based upon whether they are linked in. We need
to avoid executing them if we boot a dual SoC/PC type kernel on a PC class
system.
Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Jacob Pan [Mon, 13 Feb 2012 12:59:20 +0000 (12:59 +0000)]
x86/mrst/pci: v4l/atomisp: treat atomisp as real pci device
ATOMISP on Medfield is a real PCI device which should be handled differently
than the fake PCI devices on south complex. PCI type 1 access is used for
accessing config space this also has other impact such as PM D3 delay. There
shouldn't be any need for reading base address from IUNIT via msg bus.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Jacob Pan [Mon, 13 Feb 2012 12:59:00 +0000 (12:59 +0000)]
x86/mrst/pci: assign d3_delay to 0 for Langwell devices
Langwell devices are not true pci devices, they are not subject to the 10 ms
d3 to d0 delay required by pci spec. This patch assigns d3_delay to 0 for all
langwell pci devices.
We can also power off devices that are not really used by the OS
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
An un-wanted interrupt is generated when PCI driver switches from
MSI/MSI-X to INTx while shutting down the device. The interrupt does
not happen if MSI/MSI-X is not used on the device.
I confirmed that this problem does not happen if pcie_hp=nomsi was
specified and hotplug operation worked fine as usual.
v2: Automatically disable MSI/MSI-X against following device:
PCI bridge: Integrated Device Technology, Inc. Device 807f (rev 02)
v3: Based on the review comment, combile the if statements.
v4: Removed module parameter.
Move some code to build pciehp as a module.
Move device specific code to driver/pci/quirks.c.
v5: Drop a device specific code until getting a vendor statement.
Yinghai Lu [Fri, 10 Feb 2012 23:33:47 +0000 (15:33 -0800)]
PCI: Fix "cardbus bridge resources as optional" size handling
We should not set the requested size to -2; that will confuse the
resource list sorting with align when SIZEALIGN is used.
Change to STARTALIGN and pass align from start; we are safe to do that
just as we do that regular pci bridge. In the long run, we should just
treat cardbus like a regular pci bridge.
Also fix the case when realloc_head is not passed: we should keep the
requested size.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Tested-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCI / PM: Disable wakeup during shutdown for devices not enabled to wake up
If a PCI device is enabled to generate wakeup signals (PME) when put
into a low-power state by runtime PM, it will be still enabled to
generate those signals after the system shutdown, unless its driver's
.shutdown() callback takes care of the wakeup signals generation
setting. Moreover, there are devices that are not enabled to wake
up the system and that are configured by runtime PM to generate
wakeup signals so that (runtime) remote wakeup works with them.
Those devices should be reconfigured during system shutdown so that
they don't generate wakeup signals, but at least some drivers don't
do that. However, that very well may be done by the PCI core so
that drivers don't have to worry about it. For this reason, modify
pci_device_shutdown() to disable the generation of wakeup events for
devices not supposed to wake up the system.
References: https://bugzilla.kernel.org/show_bug.cgi?id=37952 Reported-and-tested-by: Kamil Iskra <kamil.54002@iskra.name> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Sun, 5 Feb 2012 06:55:01 +0000 (22:55 -0800)]
PCI: Fix /sys warning when sriov enabled and card is hot removed
sysfs is a bit stricter now and emits warnings in more cases.
For SRIOV hotplug, we are calling pci_stop_dev() for each VF first
(after we update pci_stop_bus_devices) which remove each VF subdir. So
double check the VF dir in /sys before trying to remove the physfn link.
Signed-of-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Matthew Garrett [Fri, 3 Feb 2012 15:18:13 +0000 (10:18 -0500)]
PCI: pcie: Add support for setting default ASPM policy
Distributions may wish to provide different defaults for PCIE ASPM
depending on their target audience. Provide a configuration option for
choosing the default policy.
Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Thomas Jarosch [Wed, 7 Dec 2011 21:08:11 +0000 (22:08 +0100)]
PCI: Add quirk for still enabled interrupts on Intel Sandy Bridge GPUs
Some BIOS implementations leave the Intel GPU interrupts enabled,
even though no one is handling them (f.e. i915 driver is never loaded).
Additionally the interrupt destination is not set up properly
and the interrupt ends up -somewhere-.
These spurious interrupts are "sticky" and the kernel disables
the (shared) interrupt line after 100.000+ generated interrupts.
Fix it by disabling the still enabled interrupts.
This resolves crashes often seen on monitor unplug.
Tested on the following boards:
- Intel DH61CR: Affected
- Intel DH67BL: Affected
- Intel S1200KP server board: Affected
- Asus P8H61-M LE: Affected, but system does not crash.
Probably the IRQ ends up somewhere unnoticed.
According to reports on the net, the Intel DH61WW board is also affected.
Many thanks to Jesse Barnes from Intel for helping
with the register configuration and to Intel in general
for providing public hardware documentation.
Signed-off-by: Thomas Jarosch <thomas.jarosch@intra2net.com> Tested-by: Charlie Suffin <charlie.suffin@stratus.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Arjan van de Ven [Tue, 31 Jan 2012 04:52:07 +0000 (20:52 -0800)]
PCI: Annotate PCI quirks in initcall_debug style
While diagnosing some boot time issues on a platform, all that I
could see in the bootgraph/dmesg was that the system was spending
a lot of time in applying one or more PCI quirks... which
was virtually undebuggable.
This patch adds printk's in "initcall_debug" style to the dmesg,
which are added when the user asks for the initcall_debug
(the nr one tool to use when debugging boot hangs or boot time issues)
kernel command line option.
v2: add #includes so quirks can build on non-x86
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Kay, Allen M [Thu, 26 Jan 2012 18:25:53 +0000 (10:25 -0800)]
PCI: check for pci bar restore completion and retry
On some OEM systems, pci_restore_state() is called while FLR has not yet
completed. As a result, PCI BAR register restore is not successful. This fix
reads back the restored value and compares it with saved value and re-tries 10
times before giving up.
Signed-off-by: Jean Guyader <jean.guyader@eu.citrix.com> Signed-off-by: Eric Chanudet <eric.chanudet@citrix.com> Signed-off-by: Allen Kay <allen.m.kay@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 27 Jan 2012 18:55:15 +0000 (10:55 -0800)]
PCI: pciehp: Disable/enable link during slot power off/on
On a system with a repeater on the system board to support gen2 hotplug,
we found that when an ExpressModule is removed from some slots,
/var/log/messages will be full of "card present/not present" warnings.
It turns out the root complex is continually trying to train the link to
the repeater because the repeater has not been reset.
This patch will disable the link at removal time to allow the repeater
to be reset properly. This also prevents a potential AER message at
removal time.
Also, when testing hotplug on a system under development, we found if we
boot the system without an EM installed, and later hot-add an EM, it
does not work with Linux, but another OS is ok. The root cause is that
BIOS left link disabled when slot was empty at boot time, and other OS
is modifying the link disable bit in link ctrl during power on/off.
So we should do the same thing to disable/enable link during power off/on.
-v2: check link DLLA bit instead of 100ms waiting.
Separate link disable/enable functions to another patch.
Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 27 Jan 2012 18:55:12 +0000 (10:55 -0800)]
PCI: pciehp: make check_link_active more helpful
A few changes:
- remove the 'inline' and let the complier decide
- return a bool to indicate whether the link was active
- add a debug message to indicate link state when it beocmes active
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Fri, 27 Jan 2012 18:55:11 +0000 (10:55 -0800)]
PCI: pciehp: replace unconditional sleep with config space access check
During reviewing
| PCI: pciehp: wait 1000 ms before Link Training check
Linus said:
>...
> That's a *long* time, and it's irritating to the user. It makes the
> user think "the machine is slow".
>...
> And quite frankly, an unconditional one-second delay here seems bad.
>Two seconds was unacceptable, one second is just bad.
Try to access the pci conf of a pci device that is supposed to show up
in 1s. If we can read back a valid vendor/device id, we can return
early.
Related discussion could be found:
https://lkml.org/lkml/2011/12/6/339
-v2: seperate code to pci_bus_read_dev_vendor_id() from pci_scan_device()
and reuse it from pciehp code. Suggested by Matthew Wilcox.
-v3: According to Kenj, don't use array in stack, and don't wait too long
for crs, also return fail status if not found.
Also separate pci_bus_dev_read_vendor_id() change to another patch.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
root complex: 80:02.2
pci express modules: have pcie switch and are listed as b0:00.0, b1:02.0 and b1:03.0.
end devices are b2:00.0 and b3.00.0.
VFs are: b2:00.1,... b2:00.3, and b3:00.1,...,b3:00.3
Root cause: when doing pci_stop_bus_device() with phys fn, it will stop
virt fn and remove the fn, so
list_for_each_safe(l, n, &bus->devices)
will have problem to refer freed n that is pointed to vf entry.
Solution is just replacing list_for_each_safe() with
list_for_each_prev_safe(). This will make sure we can get valid n pointer
to PF instead of the freed VF pointer (because newly added devices are
inserted to the bus->devices list tail).
During reviewing the patch, Bjorn said:
| The PCI hot-remove path calls pci_stop_bus_devices() via
| pci_remove_bus_device().
|
| pci_stop_bus_devices() traverses the bus->devices list (point A below),
| stopping each device in turn, which calls the driver remove() method. When
| the device is an SR-IOV PF, the driver calls pci_disable_sriov(), which
| also uses pci_remove_bus_device() to remove the VF devices from the
| bus->devices list (point B).
|
| pci_remove_bus_device
| pci_stop_bus_device
| pci_stop_bus_devices(subordinate)
| list_for_each(bus->devices) <-- A
| pci_stop_bus_device(PF)
| ...
| driver->remove
| pci_disable_sriov
| ...
| pci_remove_bus_device(VF)
| <remove from bus_list> <-- B
|
| At B, we're changing the same list we're iterating through at A, so when
| the driver remove() method returns, the pci_stop_bus_devices() iterator has
| a pointer to a list entry that has already been freed.
Discussion thread can be found : https://lkml.org/lkml/2011/10/15/141
https://lkml.org/lkml/2012/1/23/360
-v5: According to Linus to make remove more robust, Change to
list_for_each_prev_safe instead. That is more reasonable, because
those devices are added to tail of the list before.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
When the BIOS does not assign resources for SRIOV BARs, kernel pci
reallocation only goes up one bridge and then gives up, failing to to
get resources for all sSRIOV BARs, even though the range is large enough
in the peer root bus.
Specifically, only the bridge at the a1:02.0 level has its resources
cleared and reallocated. The kernel does not go up to clear the bridge
at the 80:02.0 level.
To make it go to upper levels, during retry, we need to treat "good to have"
resources as "must have".
Only on the last try will we treat good to have resources as optional.
At that time, parent bridge resources will already have been released so
we'll have a chance to get everything assigned with must_have plus
good_to_have for all child devices.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Sat, 21 Jan 2012 10:08:23 +0000 (02:08 -0800)]
PCI: Make pci_rescan_bus handle add_list
This allows us to allocate resources to hotplug bridges during
remove/rescan.
We need to move the function to setup-bus.c so it can use
__pci_bus_size_bridges and __pci_bus_assign_resources directly to take
the add_list resource tracking list.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Yinghai Lu [Sat, 21 Jan 2012 10:08:22 +0000 (02:08 -0800)]
PCI: Make rescan bus increase bridge resource size if needed
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: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
After that b1:03.0 get chance to be reassigned to [f8200000-f86fffff],
but b1:02.0 will not have chance to expand, because b1:03.0 is using in
middle one.
root cause:
b1:02.0 can not be added more range, because b1:03.0 is just after it;
no space between the required ranges.
Solution:
Try to assign required + optional all together at first, and if that
fails, try again with just the required resources.
-v2: seperate add_to_list change() to another patch according to Jesse.
seperate get_res_add_size() moving to another patch according to Jesse.
add !realloc_head->next check if the list is empty to bail early
according to Jesse.
Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
xen/pciback: Support pci_reset_function, aka FLR or D3 support.
We use the __pci_reset_function_locked to perform the action.
Also on attaching ("bind") and detaching ("unbind") we save and
restore the configuration states. When the device is disconnected
from a guest we use the "pci_reset_function" to also reset the
device before being passed to another guest.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add missing iounmap in error handling code, in a case where the function
already preforms iounmap on some other execution path.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
statement S,S1;
int ret;
@@
e = \(ioremap\|ioremap_nocache\)(...)
... when != iounmap(e)
if (<+...e...+>) S
... when any
when != iounmap(e)
*if (...)
{ ... when != iounmap(e)
return ...; }
... when any
iounmap(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>