<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/arm, branch v3.7-rc5</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'stable/for-linus-3.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen</title>
<updated>2012-11-10T05:56:21+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-11-10T05:56:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0020dd0b8c03c55a15c5bf372082be4a54d84622'/>
<id>0020dd0b8c03c55a15c5bf372082be4a54d84622</id>
<content type='text'>
Pull Xen fixes from Konrad Rzeszutek Wilk:
 "There are three ARM compile fixes (we forgot to export certain
  functions and if the drivers are built as an module - we go belly-up).

  There is also an mismatch of irq_enter() / exit_idle() calls sequence
  which were fixed some time ago in other piece of codes, but failed to
  appear in the Xen code.

  Lastly a fix for to help in the field with troubleshooting in case we
  cannot get the appropriate parameter and also fallback code when
  working with very old hypervisors."

Bug-fixes:
 - Fix compile issues on ARM.
 - Fix hypercall fallback code for old hypervisors.
 - Print out which HVM parameter failed if it fails.
 - Fix idle notifier call after irq_enter.

* tag 'stable/for-linus-3.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/arm: Fix compile errors when drivers are compiled as modules (export more).
  xen/arm: Fix compile errors when drivers are compiled as modules.
  xen/generic: Disable fallback build on ARM.
  xen/events: fix RCU warning, or Call idle notifier after irq_enter()
  xen/hvm: If we fail to fetch an HVM parameter print out which flag it is.
  xen/hypercall: fix hypercall fallback code for very old hypervisors
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Xen fixes from Konrad Rzeszutek Wilk:
 "There are three ARM compile fixes (we forgot to export certain
  functions and if the drivers are built as an module - we go belly-up).

  There is also an mismatch of irq_enter() / exit_idle() calls sequence
  which were fixed some time ago in other piece of codes, but failed to
  appear in the Xen code.

  Lastly a fix for to help in the field with troubleshooting in case we
  cannot get the appropriate parameter and also fallback code when
  working with very old hypervisors."

Bug-fixes:
 - Fix compile issues on ARM.
 - Fix hypercall fallback code for old hypervisors.
 - Print out which HVM parameter failed if it fails.
 - Fix idle notifier call after irq_enter.

* tag 'stable/for-linus-3.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/arm: Fix compile errors when drivers are compiled as modules (export more).
  xen/arm: Fix compile errors when drivers are compiled as modules.
  xen/generic: Disable fallback build on ARM.
  xen/events: fix RCU warning, or Call idle notifier after irq_enter()
  xen/hvm: If we fail to fetch an HVM parameter print out which flag it is.
  xen/hypercall: fix hypercall fallback code for very old hypervisors
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/arm: Fix compile errors when drivers are compiled as modules (export more).</title>
<updated>2012-11-09T12:48:22+00:00</updated>
<author>
<name>Stefano Stabellini</name>
<email>stefano.stabellini@eu.citrix.com</email>
</author>
<published>2012-11-08T15:58:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ab277bbf662ef17ffb7fd8dd7a462a34e326e492'/>
<id>ab277bbf662ef17ffb7fd8dd7a462a34e326e492</id>
<content type='text'>
The commit 911dec0db4de6ccc544178a8ddaf9cec0a11d533
"xen/arm: Fix compile errors when drivers are compiled as modules." exports
the neccessary functions. But to guard ourselves against out-of-tree modules
and future drivers hitting this, lets export all of the relevant
hypercalls.

Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The commit 911dec0db4de6ccc544178a8ddaf9cec0a11d533
"xen/arm: Fix compile errors when drivers are compiled as modules." exports
the neccessary functions. But to guard ourselves against out-of-tree modules
and future drivers hitting this, lets export all of the relevant
hypercalls.

Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/arm: Fix compile errors when drivers are compiled as modules.</title>
<updated>2012-11-07T15:46:19+00:00</updated>
<author>
<name>Konrad Rzeszutek Wilk</name>
<email>konrad.wilk@oracle.com</email>
</author>
<published>2012-11-06T22:06:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=911dec0db4de6ccc544178a8ddaf9cec0a11d533'/>
<id>911dec0db4de6ccc544178a8ddaf9cec0a11d533</id>
<content type='text'>
We end up with:

ERROR: "HYPERVISOR_event_channel_op" [drivers/xen/xen-gntdev.ko] undefined!
ERROR: "privcmd_call" [drivers/xen/xen-privcmd.ko] undefined!
ERROR: "HYPERVISOR_grant_table_op" [drivers/net/xen-netback/xen-netback.ko] undefined!

and this patch exports said function (which is implemented in hypercall.S).

Acked-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Acked-by: Ian Campbell &lt;ian.campbell@citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We end up with:

ERROR: "HYPERVISOR_event_channel_op" [drivers/xen/xen-gntdev.ko] undefined!
ERROR: "privcmd_call" [drivers/xen/xen-privcmd.ko] undefined!
ERROR: "HYPERVISOR_grant_table_op" [drivers/net/xen-netback/xen-netback.ko] undefined!

and this patch exports said function (which is implemented in hypercall.S).

Acked-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Acked-by: Ian Campbell &lt;ian.campbell@citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm</title>
<updated>2012-11-07T03:14:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-11-07T03:14:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3cc5a2ee7fc8f67abeb91f39fd553b5d2d55b775'/>
<id>3cc5a2ee7fc8f67abeb91f39fd553b5d2d55b775</id>
<content type='text'>
Pull arm fixes from Russell King:
 "Not much here again.

  The two most notable things here are the sched_clock() fix, which was
  causing problems with the scheduling of threaded IRQs after a suspend
  event, and the vfp fix, which afaik has only been seen on some older
  OMAP boards.  Nevertheless, both are fairly important fixes."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7569/1: mm: uninitialized warning corrections
  ARM: 7567/1: io: avoid GCC's offsettable addressing modes for halfword accesses
  ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set
  ARM: 7565/1: sched: stop sched_clock() during suspend
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull arm fixes from Russell King:
 "Not much here again.

  The two most notable things here are the sched_clock() fix, which was
  causing problems with the scheduling of threaded IRQs after a suspend
  event, and the vfp fix, which afaik has only been seen on some older
  OMAP boards.  Nevertheless, both are fairly important fixes."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7569/1: mm: uninitialized warning corrections
  ARM: 7567/1: io: avoid GCC's offsettable addressing modes for halfword accesses
  ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set
  ARM: 7565/1: sched: stop sched_clock() during suspend
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7569/1: mm: uninitialized warning corrections</title>
<updated>2012-11-04T10:32:40+00:00</updated>
<author>
<name>viresh kumar</name>
<email>viresh.kumar@linaro.org</email>
</author>
<published>2012-10-31T09:40:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6404f0b71c44cfd612ddf28627de31b4604d1d6e'/>
<id>6404f0b71c44cfd612ddf28627de31b4604d1d6e</id>
<content type='text'>
The variables here are really not used uninitialized.

arch/arm/mm/alignment.c: In function 'do_alignment':
arch/arm/mm/alignment.c:327:15: warning: 'offset.un' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch/arm/mm/alignment.c:748:21: note: 'offset.un' was declared here

Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</content>
<content type='xhtml'>
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<pre>
The variables here are really not used uninitialized.

arch/arm/mm/alignment.c: In function 'do_alignment':
arch/arm/mm/alignment.c:327:15: warning: 'offset.un' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch/arm/mm/alignment.c:748:21: note: 'offset.un' was declared here

Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'stable/for-linus-3.7-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen</title>
<updated>2012-11-02T20:26:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-11-02T20:26:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=66b6a0c979e88810e753e528dd0b9aef30ba21a1'/>
<id>66b6a0c979e88810e753e528dd0b9aef30ba21a1</id>
<content type='text'>
Pull Xen bugfixes from Konrad Rzeszutek Wilk:
 - Use appropriate macros instead of hand-rolling our own (ARM).
 - Fixes if FB/KBD closed unexpectedly.
 - Fix memory leak in /dev/gntdev ioctl calls.
 - Fix overflow check in xenbus_file_write.
 - Document cleanup.
 - Performance optimization when migrating guests.

* tag 'stable/for-linus-3.7-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/mmu: Use Xen specific TLB flush instead of the generic one.
  xen/arm: use the __HVC macro
  xen/xenbus: fix overflow check in xenbus_file_write()
  xen-kbdfront: handle backend CLOSED without CLOSING
  xen-fbfront: handle backend CLOSED without CLOSING
  xen/gntdev: don't leak memory from IOCTL_GNTDEV_MAP_GRANT_REF
  x86: remove obsolete comment from asm/xen/hypervisor.h
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Xen bugfixes from Konrad Rzeszutek Wilk:
 - Use appropriate macros instead of hand-rolling our own (ARM).
 - Fixes if FB/KBD closed unexpectedly.
 - Fix memory leak in /dev/gntdev ioctl calls.
 - Fix overflow check in xenbus_file_write.
 - Document cleanup.
 - Performance optimization when migrating guests.

* tag 'stable/for-linus-3.7-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/mmu: Use Xen specific TLB flush instead of the generic one.
  xen/arm: use the __HVC macro
  xen/xenbus: fix overflow check in xenbus_file_write()
  xen-kbdfront: handle backend CLOSED without CLOSING
  xen-fbfront: handle backend CLOSED without CLOSING
  xen/gntdev: don't leak memory from IOCTL_GNTDEV_MAP_GRANT_REF
  x86: remove obsolete comment from asm/xen/hypervisor.h
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/arm: use the __HVC macro</title>
<updated>2012-10-30T14:41:19+00:00</updated>
<author>
<name>Stefano Stabellini</name>
<email>stefano.stabellini@eu.citrix.com</email>
</author>
<published>2012-10-24T15:26:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c8d258a7b2b6633b79cad4464e8dfb3dc328d897'/>
<id>c8d258a7b2b6633b79cad4464e8dfb3dc328d897</id>
<content type='text'>
Use the new __HVC macro in hypercall.S.

Signed-off-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use the new __HVC macro in hypercall.S.

Signed-off-by: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7567/1: io: avoid GCC's offsettable addressing modes for halfword accesses</title>
<updated>2012-10-29T10:04:27+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2012-10-26T17:42:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7629a9f661f72eb383fb896e59efea1eac74e882'/>
<id>7629a9f661f72eb383fb896e59efea1eac74e882</id>
<content type='text'>
Using the 'o' memory constraint in inline assembly can result in GCC
generating invalid immediate offsets for memory access instructions with
reduced addressing capabilities (i.e. smaller than 12-bit immediate
offsets):

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54983

As there is no constraint to specify the exact addressing mode we need,
fallback to using 'Q' exclusively for halfword I/O accesses. This may
emit an additional add instruction (using an extra register) in order
to construct the address but it will always be accepted by GAS.

Reported-by: Bastian Hecht &lt;hechtb@googlemail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Using the 'o' memory constraint in inline assembly can result in GCC
generating invalid immediate offsets for memory access instructions with
reduced addressing capabilities (i.e. smaller than 12-bit immediate
offsets):

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54983

As there is no constraint to specify the exact addressing mode we need,
fallback to using 'Q' exclusively for halfword I/O accesses. This may
emit an additional add instruction (using an extra register) in order
to construct the address but it will always be accepted by GAS.

Reported-by: Bastian Hecht &lt;hechtb@googlemail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set</title>
<updated>2012-10-29T10:04:05+00:00</updated>
<author>
<name>Paul Walmsley</name>
<email>paul@pwsan.com</email>
</author>
<published>2012-10-23T19:32:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=39141ddfb63a664f26d3f42f64ee386e879b492c'/>
<id>39141ddfb63a664f26d3f42f64ee386e879b492c</id>
<content type='text'>
After commit 846a136881b8f73c1f74250bf6acfaa309cab1f2 ("ARM: vfp: fix
saving d16-d31 vfp registers on v6+ kernels"), the OMAP 2430SDP board
started crashing during boot with omap2plus_defconfig:

[    3.875122] mmcblk0: mmc0:e624 SD04G 3.69 GiB
[    3.915954]  mmcblk0: p1
[    4.086639] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
[    4.093719] Modules linked in:
[    4.096954] CPU: 0    Not tainted  (3.6.0-02232-g759e00b #570)
[    4.103149] PC is at vfp_reload_hw+0x1c/0x44
[    4.107666] LR is at __und_usr_fault_32+0x0/0x8

It turns out that the context save/restore fix unmasked a latent bug
in commit 5aaf254409f8d58229107b59507a8235b715a960 ("ARM: 6203/1: Make
VFPv3 usable on ARMv6").  When CONFIG_VFPv3 is set, but the kernel is
booted on a pre-VFPv3 core, the code attempts to save and restore the
d16-d31 VFP registers.  These are only present on non-D16 VFPv3+, so
this results in an undefined instruction exception.  The code didn't
crash before commit 846a136 because the save and restore code was
only touching d0-d15, present on all VFP.

Fix by implementing a request from Russell King to add a new HWCAP
flag that affirmatively indicates the presence of the d16-d31
registers:

   http://marc.info/?l=linux-arm-kernel&amp;m=135013547905283&amp;w=2

and some feedback from Måns to clarify the name of the HWCAP flag.

Signed-off-by: Paul Walmsley &lt;paul@pwsan.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Dave Martin &lt;dave.martin@linaro.org&gt;
Cc: Måns Rullgård &lt;mans.rullgard@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After commit 846a136881b8f73c1f74250bf6acfaa309cab1f2 ("ARM: vfp: fix
saving d16-d31 vfp registers on v6+ kernels"), the OMAP 2430SDP board
started crashing during boot with omap2plus_defconfig:

[    3.875122] mmcblk0: mmc0:e624 SD04G 3.69 GiB
[    3.915954]  mmcblk0: p1
[    4.086639] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
[    4.093719] Modules linked in:
[    4.096954] CPU: 0    Not tainted  (3.6.0-02232-g759e00b #570)
[    4.103149] PC is at vfp_reload_hw+0x1c/0x44
[    4.107666] LR is at __und_usr_fault_32+0x0/0x8

It turns out that the context save/restore fix unmasked a latent bug
in commit 5aaf254409f8d58229107b59507a8235b715a960 ("ARM: 6203/1: Make
VFPv3 usable on ARMv6").  When CONFIG_VFPv3 is set, but the kernel is
booted on a pre-VFPv3 core, the code attempts to save and restore the
d16-d31 VFP registers.  These are only present on non-D16 VFPv3+, so
this results in an undefined instruction exception.  The code didn't
crash before commit 846a136 because the save and restore code was
only touching d0-d15, present on all VFP.

Fix by implementing a request from Russell King to add a new HWCAP
flag that affirmatively indicates the presence of the d16-d31
registers:

   http://marc.info/?l=linux-arm-kernel&amp;m=135013547905283&amp;w=2

and some feedback from Måns to clarify the name of the HWCAP flag.

Signed-off-by: Paul Walmsley &lt;paul@pwsan.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Dave Martin &lt;dave.martin@linaro.org&gt;
Cc: Måns Rullgård &lt;mans.rullgard@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7565/1: sched: stop sched_clock() during suspend</title>
<updated>2012-10-29T10:02:49+00:00</updated>
<author>
<name>Felipe Balbi 2</name>
<email>balbi@ti.com</email>
</author>
<published>2012-10-23T18:00:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6a4dae5e138a32b45ca5218cc2b81802f9d378c3'/>
<id>6a4dae5e138a32b45ca5218cc2b81802f9d378c3</id>
<content type='text'>
The scheduler imposes a requirement to sched_clock()
which is to stop the clock during suspend, if we don't
do that any RT thread will be rescheduled in the future
which might cause any sort of problems.

This became an issue on OMAP when we converted omap-i2c.c
to use threaded IRQs, it turned out that depending on how
much time we spent on suspend, the I2C IRQ thread would
end up being rescheduled so far in the future that I2C
transfers would timeout and, because omap_hsmmc depends
on an I2C-connected device to detect if an MMC card is
inserted in the slot, our rootfs would just vanish.

arch/arm/kernel/sched_clock.c already had an optional
implementation (sched_clock_needs_suspend()) which would
handle scheduler's requirement properly, what this patch
does is simply to make that implementation non-optional.

Note that this has the side-effect that printk timings
won't reflect the actual time spent on suspend so other
methods to measure that will have to be used.

This has been tested with beagleboard XM (OMAP3630) and
pandaboard rev A3 (OMAP4430). Suspend to RAM is now working
after this patch.

Thanks to Kevin Hilman for helping out with debugging.

Acked-by: Kevin Hilman &lt;khilman@ti.com&gt;
Acked-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Felipe Balbi &lt;balbi@ti.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The scheduler imposes a requirement to sched_clock()
which is to stop the clock during suspend, if we don't
do that any RT thread will be rescheduled in the future
which might cause any sort of problems.

This became an issue on OMAP when we converted omap-i2c.c
to use threaded IRQs, it turned out that depending on how
much time we spent on suspend, the I2C IRQ thread would
end up being rescheduled so far in the future that I2C
transfers would timeout and, because omap_hsmmc depends
on an I2C-connected device to detect if an MMC card is
inserted in the slot, our rootfs would just vanish.

arch/arm/kernel/sched_clock.c already had an optional
implementation (sched_clock_needs_suspend()) which would
handle scheduler's requirement properly, what this patch
does is simply to make that implementation non-optional.

Note that this has the side-effect that printk timings
won't reflect the actual time spent on suspend so other
methods to measure that will have to be used.

This has been tested with beagleboard XM (OMAP3630) and
pandaboard rev A3 (OMAP4430). Suspend to RAM is now working
after this patch.

Thanks to Kevin Hilman for helping out with debugging.

Acked-by: Kevin Hilman &lt;khilman@ti.com&gt;
Acked-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Felipe Balbi &lt;balbi@ti.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
</pre>
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