Commit Graph

119 Commits

Author SHA1 Message Date
Yijing Wang
c2be6f93b3 PCI: pciehp: Use per-slot workqueues to avoid deadlock
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.

The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port.  When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method.  That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  pciehp_queue_pushbutton_work
    queue_work(pciehp_wq)                   # queue pciehp_power_thread
    ...

  pciehp_power_thread
    pciehp_disable_slot
      remove_board
	pciehp_unconfigure_device
	  pci_stop_and_remove_bus_device
	    ...
	      pciehp_remove                 # pciehp driver .remove method
		pciehp_release_ctrl
		  pcie_cleanup_slot
		    flush_workqueue(pciehp_wq)

This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.

[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
2013-01-12 13:56:33 -07:00
Jiang Liu
537a77e65d PCI/pciehp: Use PCI Express Capability accessors
Use PCI Express Capability access functions to simplify pciehp.

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>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2012-08-23 10:11:11 -06:00
Yinghai Lu
e73cfecdfc PCI: pciehp: remove unused pciehp_get_max_lnk_width(), pciehp_get_cur_lnk_width()
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2012-07-12 15:41:32 -06:00
Yinghai Lu
2debd92899 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>
2012-02-14 08:45:02 -08:00
Yinghai Lu
7f822999e1 PCI: pciehp: Add Disable/enable link functions
Will use it during power off/on of slots

Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-02-14 08:45:01 -08:00
Yinghai Lu
bffe4f72fc PCI: pciehp: Add pcie_wait_link_not_active()
Will use it for link disable status checking.

Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-02-14 08:45:01 -08:00
Yinghai Lu
4e2ce405b2 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>
2012-02-14 08:45:00 -08:00
Yinghai Lu
2f5d8e4ff9 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>
2012-02-14 08:45:00 -08:00
Kenji Kaneshige
486b10b9f4 PCI: pciehp: Handle push button event asynchronously
Use non-ordered workqueue for attention button events.

Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in pciehp as a result.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-12-05 10:21:47 -08:00
Kenji Kaneshige
b3c0045422 PCI: pciehp: wait 100 ms after Link Training check
If the port supports Link speeds greater than 5.0 GT/s, we must wait
for 100 ms after Link training completes before sending configuration
request.

Acked-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-11-11 09:31:43 -08:00
Kenji Kaneshige
0027cb3e19 PCI: pciehp: wait 1000 ms before Link Training check
We need to wait for 1000 ms after Data Link Layer Link Active (DLLLA)
bit reads 1b before sending configuration request. Currently pciehp
does this wait after checking Link Training (LT) bit. But we need it
before checking LT bit because LT is still set even after DLLLA bit is
set on some platforms.

Acked-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-11-11 09:31:34 -08:00
Yinghai Lu
fdbd3ce9ef PCI: pciehp: Retrieve link speed after link is trained
During hot plug, board_added will call pciehp_power_on_slot().
But link speed is updated in pciehp_power_on_slot().

We should not update link speed there, because that is too early.

So move the link speed update to pciehp_check_link_status() after making
sure the link has been trained.

-v2: fix compile warning that Kenji found.

Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-11-07 08:07:34 -08:00
Kenji Kaneshige
0cab0841dc PCI: pciehp: change wait time for valid configuration access
Naoki Yanagimoto reported that configuration read on some hot-added
PCIe device returns invalid value. This patch fixes this problem.

According to the PCIe spec, software must wait for at least 1 second
to judge if the hot-added device is broken after Data Link Layer State
Changed Event. This patch changes pciehp driver to wait for 1 second
after the Data Link Layer State Changed Event is detected before
initiating a configuration access instead of 100 ms.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Naoki Yanagimoto <yanagimoto@np.css.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-07-22 09:06:41 -07:00
Tejun Heo
a827ea307b pciehp: update workqueue usage
* Rename pciehp_wq to pciehp_ordered_wq and add non-ordered pciehp_wq
  which is used instead of the system workqueue.  This is to remove
  the use of flush_scheduled_work() which is deprecated and scheduled
  for removal.

* With cmwq in place, there's no point in creating workqueues lazily.
  Create both pciehp_wq and pciehp_ordered_wq upfront.

* Include workqueue.h from pciehp.h.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-10-18 08:31:02 +02:00
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
Bjorn Helgaas
e1944c6b0f PCI: print resources consistently with %pR
No functional change; just print resources in the conventional style.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-03-24 13:21:36 -07:00
Matthew Wilcox
3749c51ac6 PCI: Make current and maximum bus speeds part of the PCI core
Move the max_bus_speed and cur_bus_speed into the pci_bus.  Expose the
values through the PCI slot driver instead of the hotplug slot driver.
Update all the hotplug drivers to use the pci_bus instead of their own
data structures.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22 16:15:17 -08:00
Matthew Wilcox
536c8cb49e PCI: Unify pcie_link_speed and pci_bus_speed
These enums must not overlap anyway, since we only have a single
pci_bus_speed_strings array.  Use a single enum, and move it to
pci.h.  Add 'SPEED' to the pcie names to make it clear what they are.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22 16:15:17 -08:00
Kenji Kaneshige
5651c48cfa PCI pciehp: fix power fault interrupt storm problem
Enabling power fault detected event notification in current pciehp
might cause power fault interrupt storm on some machines. On those
machines. On those machines, power fault detected bit in the slot
status register was set again immediately when it is cleared in the
interrupt service routine, and next power fault detected interrupt was
notified again. Therefore, disable power fault detected event
notification for now.

This patch also removes unnecessary handling for power fault cleared
event because this event is not supported by PCIe spec.

Tested-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-24 15:25:19 -08:00
Kenji Kaneshige
1518c17ab7 pciehp: use pci_pcie_cap()
Use pci_pcie_cap() instead of pci_find_capability() to get PCIe capability
offset in pciehp driver. This avoids unnecessary search in PCI
configuration space. This patch also removes 'cap_base' field in
struct controller, that was used to hold PCIe capability offset by
pciehp itself.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-24 15:25:15 -08:00
Kenji Kaneshige
445f798555 PCI: pciehp: return error on read/write failure
Current pciehp returns successfully on read/write failure with dummy
state values. It should return error instead.

With this patch, pciehp no longer uses hotplug_slot_info data
structure. So this also removes hotplug_slot_info related code. But
note that it still allocates hotplug_slot_info because it is required
by pci hotplug core.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:01:59 -08:00
Kenji Kaneshige
3c3a1b1759 PCI: pciehp: remove wrong workaround for bad DLLP
Remove wrong workaround for BAD DLLP error, which confused surprise
down error with DLL errors.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:01:28 -08:00
Kenji Kaneshige
f22daf1fb9 PCI: pciehp: disable DLL state changed event notification
Current pciehp doesn't handle Data Link Layer State Changed Event
notification. So it needs to be disabled at initialization time,
otherwise other event notifications are not generated.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:01:12 -08:00
Kenji Kaneshige
07a09694de PCI: pciehp: remove number field
Since slot_cap field in struct controller contains physical slot
number informationq, we don't need number field in struct slot.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:36 -07:00
Kenji Kaneshige
82a9e79ef1 PCI: pciehp: remove hpc_ops
The struct hpc_ops seems a set of hooks to controller specific
routines. But, it is meaningless because no hotplug controller driver
follows this framework.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:31 -07:00
Kenji Kaneshige
385e24917e PCI: pciehp: remove pci_dev field
Since we have a pointer to pcie_device in struct controller, we don't
need a pointer to pci_dev.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:25 -07:00
Kenji Kaneshige
6aaa6d06f5 PCI: pciehp: remove crit_sect mutex
The crit_sect mutex defined in struct controller is to serialize
hot-plug operations against multiple slots under the same bus. But,
since PCIe doesnstream port has only one slot at most, it is
meaningless and we don't need it.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:18 -07:00
Kenji Kaneshige
d54798f034 PCI: pciehp: remove first_slot field
The slot number can be calculated only by physical slot number field
in the slot capabilities register. So the first_slot field in struct
controller is meaningless and we don't need it.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:09 -07:00
Kenji Kaneshige
a2359a334f PCI: pciehp: remove slot_device_offset field
Since the device number of the hot-slot under the PCIe downstream port
is always 0, the slot_device_offset field in the slot is meaningless
and we don't need it.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:02 -07:00
Kenji Kaneshige
0e3631593c PCI: pciehp: remove hp_slot field
The hp_slot field is to identify the slot under the same
controller. But, since PCIe downstream port has only one slot at most,
it is meaningless and we don't need it.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:58 -07:00
Kenji Kaneshige
d689f7eb36 PCI: pciehp: remove device field
The device field in the struct slot is not necessary because it is
always 0 in pciehp driver.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:51 -07:00
Kenji Kaneshige
ab9c6c8670 PCI: pciehp: remove bus field
The bus field in struct slot is not necessary.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:46 -07:00
Kenji Kaneshige
e23727da77 PCI: pciehp: remove num_slots field
Since PCIe downstream port has only one slot at most, we don't need
num_slots field in struct controller. Note that struct controller
itself doesn't exist if PCIe downstream port has no slot.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:36 -07:00
Kenji Kaneshige
8720d27dab PCI: pciehp: remove slot_list field
Since PCIe downstream port has only one slot at most, we don't need
'slot_list' linked list to manage multiple slots under the port.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:31 -07:00
Kenji Kaneshige
825c423a35 PCI hotplug: add support for 5.0G link speed
Add support for PCI-E 5.0 GT/s in max_bus_speed and cur_bus_speed.

Reviewed-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 13:29:50 -07:00
Kenji Kaneshige
bd3d99c170 PCI: Remove untested Electromechanical Interlock (EMI) support in pciehp.
The EMI support in pciehp is obviously broken. It is implemented using
struct hotplug_slot_attribute, but sysfs_ops for pci_slot_ktype is NOT
for struct hotplug_slot_attribute, but for struct pci_slot_attribute.
This bug had been there for a long time, maybe it was introduced when
PCI slot framework was introduced. The reason why this bug didn't
cause any problem is maybe the EMI support is not tested at all
because of lack of test environment.

As described above, the EMI support in pciehp seems not to be tested
at all. So this patch removes EMI support from pciehp, instead of
fixing the bug.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:10 -07:00
Kenji Kaneshige
99f0169c17 PCI: pciehp: enable software notification on empty slots
Current pciehp disables software notification of adapter presence
changed event and MRL changed event when slot is turned off. Because
of this, there is no way to detect those events on empty slots in the
current pciehp implementation.

According to the past discussion(*), this behavior was introduced to
prevent endless loop that could happen if pcie_isr() runs after power
fault is detected on a certain platform whose stickey power-fault bit
remains on till the slot is powered on again.

(*) http://sourceforge.net/mailarchive/message.php?msg_id=20051130135409.A14918%40unix-os.sc.intel.com

I think this endless loop can be avoided using one bit flag that
indicates power fault had been detected, instead of disabling software
notification of adapter present changed event and MRL changed event.

With this patch, we can enable software notification mechanism of
presence changed and MRL changed event on the empty slots again.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19 19:29:29 -07:00
Kenji Kaneshige
81b840cd27 PCI: pciehp: fix possible endless loop in pcie_isr
Fix possible endless loop in pcie_isr.

Currently, pcie_isr() (interrupt service routine of pciehp) can end up in an
endless loop if the Slot Status register is set again immediately after being
cleared. According to the past discussion (see below URL) this case can happen
if the power fault detected bit is set during handling.

http://sourceforge.net/mailarchive/message.php?msg_id=20051130135409.A14918%40unix-os.sc.intel.com

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19 19:29:28 -07:00
Eric W. Biederman
dbc7e1e567 PCI: pciehp: Handle interrupts that happen during initialization.
Move the enabling of interrupts after all of the data structures
are setup so that we can safely run the interrupt handler as
soon as it is registered.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2009-02-24 09:36:56 -08:00
Kenji Kaneshige
322162a71b PCI: pciehp: cleanup register and field definitions
Clean up register definitions related to PCI Express Hot plug.

  - Add register definitions into include/linux/pci_regs.h, and use
    them instead of pciehp's locally definied register definitions.
  - Remove pciehp's locally defined register definitions
  - Remove unused register definitions in pciehp.
  - Some minor cleanups.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:22 -08:00
Kenji Kaneshige
67f6533802 PCI: pciehp: ignore undefined bit in link status register
Bit 10 in Link Status register used to be defined as Training Error in
the PCI Express 1.0a specification. But it was removed by Training Error
ECN and is no longer defined. So pciehp must ignore the value read from
it.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:21 -08:00
Taku Izumi
18b341b76c PCI hotplug: pciehp: message refinement
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>
2008-10-23 14:47:39 -07:00
Kenji Kaneshige
f18e9625e0 PCI hotplug: pciehp: poll data link layer link active
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>
2008-10-22 16:42:45 -07:00
Kenji Kaneshige
b84346ef74 PCI hotplug: pciehp: fix possible memory leak in pcie_init
Fix the error paths in pcie_init to avoid leaking memory.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-22 16:42:45 -07:00
Alex Chiang
e1acb24f05 PCI: pciehp: remove 'name' parameter
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>
2008-10-22 16:42:42 -07:00
Taku Izumi
7f2feec140 PCI: pciehp: replace printk with dev_printk
This patch replaces printks within pciehp module with dev_printks.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-20 10:53:49 -07:00
Kenji Kaneshige
f7a10e32a1 PCI: pciehp: fix irq initialization
Current pciehp driver gets irq number from pci_dev->irq. But because
pciehp driver is a pci express port service driver, it should get irq
number from pcie_device->irq.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-20 10:53:47 -07:00
Adrian Bunk
a5827f40af PCI: fix pciehp_free_irq()
This patch fixes an obvious bug (loop was never entered) caused by
commit 820943b6fc
(pciehp: cleanup pcie_poll_cmd).

Reported-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-09-10 10:50:57 -07:00
Alex Chiang
167e782e30 PCI: pciehp: Rename duplicate slot name N as N-1, N-2, N-M...
Commit 3800345f72 (pciehp: fix slot name)
introduces the pciehp_slot_with_bus module parameter, which was intended
to help work around broken firmware that assigns the same name to multiple
slots.

Commit 9e4f2e8d4d (pciehp: add message about
pciehp_slot_with_bus option) tells the user to use the above parameter
in the event of a name collision.

This approach is sub-optimal because it requires too much work from
the user.

Instead, let's rename the slot 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
	The Mth registered slot becomes N-M

In the event we overflow the slot->name parameter, we report an
error to the user.

This is a temporary fix until the entire PCI core can be reworked
such that individual drivers no longer have to manage their own
slot names.

Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.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>
2008-08-21 15:15:10 -07:00
Jesse Barnes
56adc59d81 PCI hotplug: fix typo in pcie hotplug output
Comamnd->Command

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-07-28 11:44:32 -07:00