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44 commits

Author SHA1 Message Date
Arun Sharma
60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Holger Dengler
6bed05bcbc [S390] ap: toleration support for ap device type 10
Add toleration support for ap devices with device type 10.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 10:48:22 +02:00
Holger Dengler
cf2d007bd4 [S390] ap: skip device registration on type probe failure
The registration of an ap device will be skipped, if the device type
probing fails.
Add names of current crypto adapters to the Kconfig help.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-05-23 10:24:29 +02:00
Felix Beck
b1f933da57 [S390] zcrypt: Introduce check for 4096 bit support.
Implemented an asm in the ap bus and made it accessible for the card
specific parts of the zcrypt driver. Thus when a cex3a is recognized
a check can be performed to dermine whether the card supports 4096 bit
RSA keys.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:27 +01:00
Holger Dengler
62d146ffe3 [S390] ap bus: add support for irq statistics
Add support for AP Bus I/O interrupt statistics in /proc/interrupts.

Signed-off-by: Holger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:26 +01:00
Felix Beck
53ec24b1e6 [S390] zcrypt: Fix check to look for facility bits 2 & 65
Fix the check for ap interupts to look for facility bits 2 and 65.
Make sure that we only register interrupts for aps, if the machine
has ap interrupt support.

This patch is relevant only for the 2.6.37 stable series.

Cc: stable@kernel.org
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:46:52 +01:00
Martin Schwidefsky
14375bc4eb [S390] cleanup facility list handling
Store the facility list once at system startup with stfl/stfle and
reuse the result for all facility tests.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25 16:10:21 +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
Felix Beck
93521314cb [S390] zcrypt: Do not simultaneously schedule hrtimer
Protect the hrtimer ap_poll_timer from being scheduled at the same
time from several processes.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:36 +01:00
Felix Beck
a6a5d73a56 [S390] zcrypt: special command support for cex3 exploitation
Support for special command is implemented in the AP Bus in the NQAP
function __ap_send. This is extended for a further parameter special.
When set, the special bit, in GR0 will be set. Therefor the ap_message
struct is extended for a further bit. Thus calling functions of
__ap_send can use the special parameter in ap_message to give to
__ap_send. Affected is in the first place ap_queue_message, which is
called by the actual card driver. The second part of this support is
that the card driver for the CEX3C needs to set this special bit, when
an according CPRB is sent to the driver.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <ralph.wuerthner@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:35 +01:00
Felix Beck
5314af693d [S390] zcrypt: Do not add/remove devices in s/r callbacks
Devices are no longer removed or added in the suspend and resume
callbacks. Instead they are marked unregistered in suspend. In the
resume callback the ap_scan_bus method is scheduled. The bus scan
function will remove the old device and add new ones. This way all
the device handling will be done in only one function. Additionaly
the case where the domain might change during suspend/resume is
caught. In that case the devices qid needs to re-calculated in
order of having it found by the scan method.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-22 22:58:46 +02:00
Felix Beck
edc44fa03e [S390] zcrypt: Free ap_device if dev_set_name fails.
If dev_set_name fails during scanning the AP bus, the reserved memory
has to be freed.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 10:29:51 +02:00
Felix Beck
95f1556c35 [S390] zcrypt: Use spin_lock_bh in suspend callback
Fix lock dependency warning.

inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
bash/1442 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&ap_dev->lock){+.?...}, at: [<000003e001280404>] __ap_poll_device+0x40/0x3e8 [ap]
{IN-SOFTIRQ-W} state was registered at:
  [<000000000017f094>] __lock_acquire+0xb78/0x182c
  [<000000000017fe8e>] lock_acquire+0x146/0x178
  [<0000000000549cf2>] _spin_lock+0x5a/0x98
  [<000003e001280404>] __ap_poll_device+0x40/0x3e8 [ap]
  [<000003e001280afe>] ap_poll_all+0xaa/0x1a4 [ap]
  [<000000000014fa82>] tasklet_action+0xfe/0x1f4
  [<0000000000150a56>] __do_softirq+0x116/0x284
  [<0000000000111058>] do_softirq+0xe4/0xe8
  [<00000000001504ba>] irq_exit+0xba/0xd8
  [<00000000003dd04a>] do_IRQ+0x176/0x1fc
  [<000000000011823c>] io_return+0x0/0x8
  [<0000004bfbfd2c0e>] 0x4bfbfd2c0e

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 10:29:50 +02:00
Sebastian Ott
c630493327 [S390] proper use of device register
Don't use kfree directly after device registration started.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 10:29:45 +02:00
Felix Beck
8d406c6de2 [S390] zcrypt: fix scheduling of hrtimer ap_poll_timer
Every time a request is enqueued or there is some work outstanding
from the ap_tasklet, the ap_poll_timer is scheduled again.
Unfortunately it was permanently called. It looked as if it was
started in the past and thus imediately expired.
This has been changed. First it is checked if the hrtimer is already
expired. Then the expiring time is forwarded and the timer restarted.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-07-24 12:41:02 +02:00
Felix Beck
772f54720a [S390] ap/zcrypt: Suspend/Resume ap bus and zcrypt
Add Suspend/Resume support to ap bus and zcrypt. All enhancements are
done in the ap bus. No changes in the crypto card specific part are
necessary.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-22 12:08:21 +02:00
Mark McLoughlin
035da16fb5 s390: remove s390_root_dev_*()
Replace s390_root_dev_register() with root_device_register() etc.

[Includes fix from Cornelia Huck]

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:34 -08:00
Martin Schwidefsky
136f7a1c42 [S390] convert ap_bus printks to pr_xxx macros.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:39:24 +01:00
Christian Maaser
43c207e6e5 [S390] ap: Minor code beautification.
Changed some symbol names for a better and clearer code.

Signed-off-by: Christian Maaser <cmaaser@de.ibm.com>
Signed-off-by: Felix Beck <beckf@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:38:57 +01:00
Felix Beck
cb17a6364a [S390] zcrypt: Use of Thin Interrupts
When the machine supports AP adapter interrupts polling will be
switched off at module initialization and the driver will work in
interrupt mode.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:38:57 +01:00
Arjan van de Ven
651dab4264 Merge commit 'linus/master' into merge-linus
Conflicts:

	arch/x86/kvm/i8254.c
2008-10-17 09:20:26 -07:00
Cornelia Huck
1bf5b28539 [S390] bus_id -> dev_set_name() changes
Convert most s390 users setting bus_id to dev_set_name().
css and ccw busses are deferred since they need some special
treatment.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-10-10 21:33:50 +02:00
Arjan van de Ven
6c644eaeb2 hrtimer: convert s390 to the new hrtimer apis
In order to be able to do range hrtimers we need to use accessor functions
to the "expire" member of the hrtimer struct.
This patch converts s390 to these accessors.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2008-09-05 21:35:21 -07:00
Felix Beck
fe13723061 [S390] ap: Use high-resolution timer for polling
The ap poll mechanism is converted to use a high-resolution timer for
polling. This allows more specific polling. With this a new sysfs
attribute is introduced to specify the polling rate in nanoseconds.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:13 +02:00
Felix Beck
1749a81d62 [S390] zcrypt: Comments and kernel-doc cleanup
Comments, which suggested to be kernel-doc but were not in the right
formatting, have been corrected. Additionally some minor cleanup in
the comments has been done.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:06 +02:00
Ralph Wuerthner
faa582ca80 [S390] zcrypt: fix ap_device_list handling
In ap_device_probe() we can add the new ap device to the internal
device list only if the device probe function successfully returns.
Otherwise we might end up with an invalid device in the internal ap
device list.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-03-05 12:37:19 +01:00
Felix Beck
b90b34c680 [S390] zcrypt: Do not start ap poll thread per default
Do not start ap poll thread per default to increase perfomance with
z/VM.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-09 18:24:38 +01:00
Linus Torvalds
efefc6eb38 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (75 commits)
  PM: merge device power-management source files
  sysfs: add copyrights
  kobject: update the copyrights
  kset: add some kerneldoc to help describe what these strange things are
  Driver core: rename ktype_edd and ktype_efivar
  Driver core: rename ktype_driver
  Driver core: rename ktype_device
  Driver core: rename ktype_class
  driver core: remove subsystem_init()
  sysfs: move sysfs file poll implementation to sysfs_open_dirent
  sysfs: implement sysfs_open_dirent
  sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir
  sysfs: make sysfs_root a regular directory dirent
  sysfs: open code sysfs_attach_dentry()
  sysfs: make s_elem an anonymous union
  sysfs: make bin attr open get active reference of parent too
  sysfs: kill unnecessary NULL pointer check in sysfs_release()
  sysfs: kill unnecessary sysfs_get() in open paths
  sysfs: reposition sysfs_dirent->s_mode.
  sysfs: kill sysfs_update_file()
  ...
2007-10-12 15:49:37 -07:00
Kay Sievers
7eff2e7a8b Driver core: change add_uevent_var to use a struct
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:51:01 -07:00
Ralph Wuerthner
39aa7cf612 [S390] zcrypt: fix ap_reset_domain()
Resetting of a all queues within a domain requires that a domain must
be selected first.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-12 16:13:05 +02:00
Ralph Wuerthner
af512ed0f8 [S390] zcrypt: fix request timeout handling
Under very high load zcrypt requests may timeout while waiting on the
request queue. Modify zcrypt that timeouts are based on crypto adapter
responses. A timeout occurs only if a crypto adapter does not respond
within a given time frame to sumitted requests.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-10 11:24:52 +02:00
Eric Rannaud
bf62456eb9 uevent: use add_uevent_var() instead of open coding it
Make use of add_uevent_var() instead of (often incorrectly) open coding it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Eric Rannaud <eric.rannaud@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-27 10:57:29 -07:00
Ralph Wuerthner
e675c0d2bf [S390] zcrypt: Fix ap_poll_requests counter in lost requests error path.
In the unlikely event that an AP device lost requests, don't forget to
update the ap_poll_requests counter too. Same must happen in case an AP
device is removed while there are still outstanding requests.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-03-26 20:43:47 +02:00
Ralph Wuerthner
c6a4826473 [S390] zcrypt: Fix possible dead lock in AP bus module.
If a AP device is unconfigured __ap_poll_all() will call
device_unregister() in software interrupt context which can cause
dead locks. To fix this the device will be only marked as unconfigured
and the device_unregister() call will be done later by either
ap_scan_bus() or ap_queue_message() in process context.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-03-26 20:43:47 +02:00
Ralph Wuerthner
cf352ce0b9 [S390] zcrypt: fix possible dead lock in AP bus module
AP bus module uses bus_for_each_dev() in software interrupt context to
poll for completed requests which might cause dead locks. Solution: use
private AP device list for polling in software interrupt context.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-19 13:19:14 +01:00
Heiko Carstens
4d284cac76 [S390] Avoid excessive inlining.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:53 +01:00
Ralph Wuerthner
13e742babd [S390] zcrypt: module unload fixes.
Add code to reset all queues for a domain and add missing tasklet_kill
call to ap bus module exit code.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-15 17:18:17 +01:00
Ralph Wuerthner
85eca85039 [S390] add reset call handler to the ap bus.
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-08 15:54:07 +01:00
Al Viro
4927b3f74c [PATCH] More work_struct induced breakage (s390)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 14:51:14 -08:00
Cornelia Huck
66a4263b99 [S390] Add MODALIAS= to the uevent for the ap bus.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:40:10 +01:00
Ralph Wuerthner
f3b017d8c9 [S390] Improve AP bus device removal.
Added a call to device_unregister() in ap_scan_bus() to actively
remove unavailable AP bus devices with every bus scan. Previously
devices were only removed in ap_queue_message() or __ap_poll_all().

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-27 12:39:26 +02:00
Christian Borntraeger
d83682b397 [S390] ap bus poll thread priority.
The ap bus is supposed to have a low priority. We must use 19 instead
of -20, which is just the opposite.

Signed-off-by: Christian Borntraeger <cborntra@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-06 16:38:22 +02:00
Ralph Wuerthner
4e56296d47 [S390] zcrypt device registration/unregistration race.
Fix a race condition during AP device registration and unregistration.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-04 20:02:05 +02:00
Martin Schwidefsky
1534c3820c [S390] zcrypt adjunct processor bus.
Add a bus for the adjunct processor interface. Up to 64 devices can
be connect to the ap bus interface, each device with 16 domains. That
makes 1024 message queues. The interface is asynchronous, the answer
to a message sent to a queue needs to be received at some later point
in time. Unfortunately the interface does not provide interrupts when
a message reply is pending. So the ap bus needs to implement some
fancy polling, each active queue is polled once per 1/HZ second or
continuously if an idle cpus exsists and the poll thread is activ
(see poll_thread parameter).

The ap bus uses the sysfs path /sys/bus/ap and has two bus attributes,
ap_domain and config_time. The ap_domain selects one of the 16 domains
to be used for this system. This limits the maximum number of ap devices
to 64. The config_time attribute contains the number of seconds between
two ap bus scans to find new devices.

The ap bus uses the modalias entries of the form "ap:tN" to autoload
the ap driver for hardware type N. Currently known types are:
3 - PCICC, 4 - PCICA, 5 - PCIXCC, 6 - CEX2A and 7 - CEX2C.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 15:58:25 +02:00