I happened to notice that the ibmphp hotplug driver does something
rather silly in its init routine. It purposely calls module_put so as
to underflow its module ref count to avoid being removed from the
kernel. This is bad practice, and wrong, since it provides a window for
subsequent module_gets to reset the refcount to zero, allowing an unload
to race in and cause all sorts of mysterious panics. If the module is
unsafe to load, simply omitting the module_exit parameter is sufficient
to prevent the kernel from allowing the unload.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: build fix
make intr_remapping.c to include smp.h, so could use boot_cpu_id there
also remove old change that disabling sparseirq with !SMP
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Certain HP machines require the full 64 bits of _SUN as allowed
by the ACPI spec. Without this change, we get name collisions in
the lower 32 bits of the _SUN returned by firmware.
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Justin Chen <justin.chen@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch fixes the problem that causes an occupied slot to be turned
off even if it has a working device.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
What we have to check here before calling is err_handler->resume, not
->slot_reset. Looks like a copy & paste error from report_slot_reset.
Acked-by: Yanmin Zhang <yanmin.zhang@intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Makes a Compaq 6735s boot reliably again. It used to hang in the loop
on some boots. Give the link one second to train, otherwise break out
of the loop and reset the previously set clock bits.
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
In pci_create_slot(), the local variable 'slot_name' is allocated by
make_slot_name(), but never freed. We never use it after passing it to
the kobject core, so we should free it upon function exit.
Cc: stable@kernel.org
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: simplify code
Pass irq_desc and cfg around, instead of raw IRQ numbers - this way
we dont have to look it up again and again.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new feature
Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.
To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.
When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).
This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
for fsck sake, it's used only when parsing kernel command line...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before initialization, dev->irq may be zero. Make sure we don't disable
it at reset time in that case.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: cleanup
I got the following warnings on IA64:
linux-2.6/drivers/pci/intel-iommu.c: In function 'init_dmars':
linux-2.6/drivers/pci/intel-iommu.c:1658: warning: format '%Lx' expects type 'long long unsigned int', but argument 2 has type 'u64'
linux-2.6/drivers/pci/intel-iommu.c:1663: warning: format '%Lx' expects type 'long long unsigned int', but argument 2 has type 'u64'
Another victim of int-ll64.h versus int-l64.h confusion between platforms.
->reg_base_addr has a type of u64 - which can only be printed out
consistently if we cast its type up to LL.
[ Eventually reg_base_addr should be converted to phys_addr_t, for which
we have the %pR printk helper - but that is out of the scope of late
-rc's. ]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently acpi_run_osc() checks all the bits in _OSC result code (the
first DWORD in the capabilities buffer) to see error condition. But the
bit 0, which doesn't indicate any error, must be ignored.
The bit 0 is used as the query flag at _OSC invocation time. Some
platforms clear it during _OSC evaluation, but the others don't. On
latter platforms, current acpi_run_osc() mis-detects error when _OSC is
evaluated with query flag set because it doesn't ignore the bit 0.
Because of this, the __acpi_query_osc() always fails on such platforms.
And this is the cause of the problem that pci_osc_control_set() doesn't
work since the commit 4e39432f4d which
changed pci_osc_control_set() to use __acpi_query_osc().
Tested-by:"Tomasz Czernecki <czernecki@gmail.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The pseries PCI hotplug code has a number of issues, ranging from
incorrect resource setup to crashes, depending on what is added,
when, whether it contains a bridge, etc etc....
This fixes a whole bunch of these, while actually simplifying the code
a bit, using more generic code in the process and factoring out common
code between adding of a PHB, a slot or a device.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
pci_mmap_fits() returns the wrong answer if the sysfs resource file size
is not a multiple of the page size. vm_end and vm_start are already
page-aligned, so size - start < nr, causing mmap() to return EINVAL.
Signed-off-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix pci/rom.c kernel-doc function notation:
Warning(drivers/pci/rom.c:110): Excess function parameter or struct member 'return' description in 'pci_map_rom'
Warning(drivers/pci/rom.c:177): Excess function parameter or struct member 'return' description in 'pci_map_rom_copy'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
VPD quirks need to be called after the VPD capability is initialized.
Since VPD initialization now runs after pci_fixup_header (due to the
capabilities consolidation), VPD quirks should be done at
pci_fixup_final stage correspondingly.
Tested-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
On Thu, Oct 23, 2008 at 04:09:52PM -0700, Alexander Beregalov wrote:
> arch/x86/kernel/built-in.o: In function `iommu_setup':
> pci-dma.c:(.init.text+0x36ad): undefined reference to `forbid_dac'
> pci-dma.c:(.init.text+0x36cc): undefined reference to `forbid_dac'
> pci-dma.c:(.init.text+0x3711): undefined reference to `forbid_dac
This patch partially reverts a patch to add IOMMU support to ia64. The
forbid_dac variable was incorrectly moved to quirks.c, which isn't built
when PCI is disabled.
Tested-by: "Alexander Beregalov" <a.beregalov@gmail.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix printk format warning:
drivers/pci/hotplug/acpiphp_ibm.c:207: warning: format '%08lx' expects type 'long unsigned int', but argument 3 has type 'long long unsigned int'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This cleanup removes the resource assignment in pci_read_bridge_bases()
since it has taken care by pci_alloc_child_bus() when allocating the bus:
/* Set up default resource pointers and names.. */
for (i = 0; i < PCI_BRIDGE_RES_NUM; i++) {
child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
child->resource[i]->name = child->name;
}
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch refines messages in shpchp module. The main changes are as
follows:
- remove the trailing "."
- remove __func__ as much as possible
- capitalize the first letter of messages
- show PCI device address including its domain
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We're getting a lot of storage drivers blamed for interrupt misrouting
issues. This patch provides a standard way of reporting the problem
... and, if possible, correcting it.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch refines messages in pciehp module. The main changes are as
follows:
- remove the trailing "."
- remove __func__ as much as possible
- capitalize the first letter of messages
- show PCI device address including its domain
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The original ARI support code has a compatibility problem with non-ARI
devices. If a device doesn't support ARI, turning on ARI forwarding on
its upper level bridge will cause undefined behavior.
This fix turns on ARI forwarding only when the subordinate devices
support it.
Tested-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The following patch fixes the regression in 2.6.27 that causes kernel
NULL pointer dereference at cpqphp driver probe time. This patch should
be backported to the .27 stable series.
Seems to have been introduced by
f46753c5e3.
The root cause of this problem seems that cpqphp driver calls
pci_hp_register() wrongly. In current implementation, cpqphp driver
passes 'ctrl->pci_dev->subordinate' as a second parameter for
pci_hp_register(). But because hotplug slots and it's hotplug controller
(exists as a pci funcion) are on the same bus, it should be
'ctrl->pci_dev->bus' instead.
Cc: <stable@kernel.org>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The pattern !E && !E->fld is nonsensical. The patch below updates this
according to the assumption that && should be ||. But perhaps another
solution was intended.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@disable and_comm@
expression E;
identifier fld;
@@
- !E && !E->fld
+ !E || !E->fld
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch adds polling mechanism for Data Link Layer Link Active bit
after turning power on, instead of waiting for 1000 msec. This reduces
reduce the unnecessary long wait.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some firmware fail to properly configure P2P bridges, leaving them
with invalid bus numbers. In some cases, this happens on some embedded
4xx boards as the result of the kernel allocating different bus space
than the firmware does to host bridges while not setting
pcibios_assign_all_busses() for various reasons. In other cases, it can
just be bogus firmware.
This adds some sanity checking to the PCI probing code. If a bridge is
found whose primary bus number doesn't match the bus it's sitting on,
or whose secondary bus number not strictly above it's primary bus
number, then the bridge bus numbers are deconfigured in the first pass
of pci_scan_bridge() to be re-assigned in the second pass.
Tested-by: "Ayman El-Khashab" <AymanE@tanisys.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The PCI core now manages slot names on behalf of slot detection
and slot hotplug drivers, including the handling of duplicate
slot names.
We can use the fakephp driver to help test the new functionality.
Add a 'dup_slots' module param to force fakephp to create multiple
slots with the same name. We can then verify that the PCI core
correctly renamed the slots.
sapphire:/sys/bus/pci/slots # modprobe fakephp dup_slots
sapphire:/sys/bus/pci/slots # ls
fake fake-10 fake-3 fake-5 fake-7 fake-9
fake-1 fake-2 fake-4 fake-6 fake-8
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Now that the PCI core manages the 'name' for each individual
hotplug driver, and all drivers (except rpaphp) have been converted
to use hotplug_slot_name(), there is no need for the PCI hotplug
core to drag around its own copy of name either.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We do not need to manage our own name parameter, especially since
the PCI core can change it on our behalf, in the case of duplicate
slot names.
Remove 'name' from shpchp's version of struct slot.
This change also removes the unused struct task_event from the
slot structure.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Update the sn_hp_slot_private_alloc() interface to fill in
the correct name for us, as that function already has all
the parameters needed to determine the name.
Cc: kristen.c.accardi@intel.com
Cc: jpk@sgi.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
rpaphp tends to use slot->name directly everywhere, and doesn't
ever need slot->hotplug_slot->name.
struct hotplug_slot->name is going away, so convert rpaphp directly
manipulate its own slot->name everywhere, and don't bother touching
slot->hotplug_slot->name.
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We do not need to manage our own name parameter, especially since
the PCI core can change it on our behalf, in the case of duplicate
slot names.
Remove 'name' from pciehp's version of struct slot, and remove
unused 'task_list' as well.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Additionally, slightly rearrange the members of struct slot
so they are naturally aligned to eliminate holes.
Cc: jbarnes@virtuousgeek.org
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Remove 'name' from fakephp's struct dummy_slot, as the PCI core
will now manage our slot name for us.
Cc: jbarnes@virtuousgeek.org
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
In preparation for cleaning up the various hotplug drivers
such that they don't have to manage their own 'name' parameters
anymore, we provide the following convenience functions:
pci_slot_name()
hotplug_slot_name()
These helpers will be used by individual hotplug drivers.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Cc: jbarnes@virtuousgeek.org
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We no longer need to manage our version of hotplug_slot->name
since the PCI and hotplug core manage it on our behalf.
Now, we simply advise the PCI core of the name that we would
like, and let the core take care of the rest.
Cc: kristen.c.accardi@intel.com
Cc: scottm@somanetworks.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We do not need to manage our own name parameter, especially since
the PCI core can change it on our behalf, in the case of duplicate
slot names.
Remove 'name' from acpiphp's version of struct slot.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Prevent callers of pci_create_slot() from registering slots with
duplicate names. This condition occurs most often when PCI hotplug
drivers are loaded on platforms with broken firmware that assigns
identical names to multiple slots.
We now rename these duplicate slots on behalf of the user.
If firmware assigns the name N to multiple slots, then:
The first registered slot is assigned N
The second registered slot is assigned N-1
The third registered slot is assigned N-2
etc.
This is the permanent fix mentioned in earlier commits d6a9e9b4 and
167e782e (shpchp/pciehp: Rename duplicate slot name...).
We take advantage of the new 'hotplug' parameter in pci_create_slot()
to prevent a slot create/rename race between hotplug drivers and
detection drivers.
Scenario A:
hotplug driver detection driver
-------------- ----------------
pci_create_slot(hotplug=set)
pci_create_slot(hotplug=NULL)
The hotplug driver creates the slot with its desired name, and then
releases the semaphore. Now, the detection driver tries to create
the same slot, but it already exists. We don't care about renaming,
so return the existing slot.
Scenario B:
hotplug driver detection driver
-------------- ----------------
pci_create_slot(hotplug=NULL)
pci_create_slot(hotplug=set)
The detection driver creates the slot with name "X". Then the hotplug
driver tries to create the same slot, but wants the name "Y" instead.
We detect that we're trying to create the same slot and that we also
want a rename, so rename the slot to "Y" and return.
Scenario C:
hotplug driver hotplug driver
-------------- ----------------
pci_create_slot(hotplug=set)
pci_create_slot(hotplug=set)
Two separate hotplug drivers are attempting to claim the slot and
are passing valid hotplug_slot args to pci_create_slot(). We detect
that the slot already has a ->hotplug callback, prevent a rename,
and return -EBUSY.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Convert the pci_hotplug_slot_list_lock, which only protected the
list of hotplug slots, to a pci_hp_mutex which now protects both
interfaces.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Slot detection drivers can co-exist with hotplug drivers. The names
of the detected/claimed slots may be different depending on module
load order.
For legacy reasons, we need to allow hotplug drivers to override
the slot name if a detection driver is loaded first (and they find
the same slots).
Creating and overriding slot names should be an atomic operation,
otherwise you get a locking nightmare as various drivers race to
call pci_create_slot().
pci_create_slot() is already serialized by grabbing the pci_bus_sem.
We update the API and add a 'hotplug' param, which is:
set if the caller is a hotplug driver
NULL if the caller is a detection driver
pci_create_slot() does not actually use the 'hotplug' parameter in this
patch. A later patch will add the logic that uses it.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The GPL exported symbol pci_update_slot_number has been renamed to
pci_renumber_slot. Some of the safety checks were unnecessary and
were removed.
Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Update pci_hp_register() to take a const char *name parameter.
The motivation for this is to clean up the individual hotplug
drivers so that each one does not have to manage its own name.
The PCI core should be the place where we manage the name.
We update the interface and all callsites first, in a
"no functional change" manner, and clean up the drivers later.
Cc: kristen.c.accardi@intel.com
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Sometimes, it's necessary to enable software's ability to quiesce and
reset endpoint hardware with function-level granularity, so provide
support for it.
The patch implement Function Level Reset(FLR) feature following PCI-e
spec. And this is the first step. We would add more generic method, like
D0/D3, to allow more devices support this function.
The patch contains two functions. pcie_reset_function() is the new
driver API, and, contains some action to quiesce a device. The other
function is a helper: pcie_execute_reset_function() just executes the
reset for a particular device function.
Current the usage model is in KVM. Function reset is necessary for
assigning device to a guest, or moving it between partitions.
For Function Level Reset(FLR), please refer to PCI Express spec chapter
6.6.2.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Neil Horman