On certain bios, resume hangs if cpus are allowed to enter idle states
during suspend [1].
This was fixed in apci idle driver [2].But intel_idle driver does not
have this fix. Thus instead of replicating the fix in both the idle
drivers, or in more platform specific idle drivers if needed, the
more general cpuidle infrastructure could handle this.
A suspend callback in cpuidle_driver could handle this fix. But
a cpuidle_driver provides only basic functionalities like platform idle
state detection capability and mechanisms to support entry and exit
into CPU idle states. All other cpuidle functions are found in the
cpuidle generic infrastructure for good reason that all cpuidle
drivers, irrepective of their platforms will support these functions.
One option therefore would be to register a suspend callback in cpuidle
which handles this fix. This could be called through a PM_SUSPEND_PREPARE
notifier. But this is too generic a notfier for a driver to handle.
Also, ideally the job of cpuidle is not to handle side effects of suspend.
It should expose the interfaces which "handle cpuidle 'during' suspend"
or any other operation, which the subsystems call during that respective
operation.
The fix demands that during suspend, no cpus should be allowed to enter
deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle
ensures that. Not just that it also kicks all the cpus which are already
in idle out of their idle states which was being done during cpu hotplug
through a CPU_DYING_FROZEN callbacks.
Now the question arises about when during suspend should
cpuidle_uninstall_idle_handler() be called. Since we are dealing with
drivers it seems best to call this function during dpm_suspend().
Delaying the call till dpm_suspend_noirq() does no harm, as long as it is
before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg
operations. In dpm_suspend_noirq(), it would be wise to place this call
before suspend_device_irqs() to avoid ugly interactions with the same.
Ananlogously, during resume.
References:
[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075.
[2] http://marc.info/?l=linux-pm&m=133958534231884&w=2
Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
__device_suspend() must always send a completion. Otherwise, parent
devices will wait forever.
Commit 1e2ef05b, "PM: Limit race conditions between runtime PM and
system sleep (v2)", introduced a regression by short-circuiting the
complete_all() for certain error cases.
This patch fixes the bug by always signalling a completion.
Addresses http://crosbug.com/31972
Tested by injecting an abort.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Here are some fixes for 3.5-rc4 that resolve the kmsg problems that
people have reported showing up after the printk and kmsg changes went
into 3.5-rc1. There are also a smattering of other tiny fixes for the
extcon and hyper-v drivers that people have reported.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and printk fixes from Greg Kroah-Hartman:
"Here are some fixes for 3.5-rc4 that resolve the kmsg problems that
people have reported showing up after the printk and kmsg changes went
into 3.5-rc1. There are also a smattering of other tiny fixes for the
extcon and hyper-v drivers that people have reported.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'driver-core-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
extcon: max8997: Add missing kfree for info->edev in max8997_muic_remove()
extcon: Set platform drvdata in gpio_extcon_probe() and fix irq leak
extcon: Fix wrong index in max8997_extcon_cable[]
kmsg - kmsg_dump() fix CONFIG_PRINTK=n compilation
printk: return -EINVAL if the message len is bigger than the buf size
printk: use mutex lock to stop syslog_seq from going wild
kmsg - kmsg_dump() use iterator to receive log buffer content
vme: change maintainer e-mail address
Extcon: Don't try to create duplicate link names
driver core: fixup reversed deferred probe order
printk: Fix alignment of buf causing crash on ARM EABI
Tools: hv: verify origin of netlink connector message
If driver requests probe deferral,
it will be added to deferred_probe_pending_list
by driver_deferred_probe_add(), but, it used list_add().
Because of that, deferred probe will be run as reversed order.
This patch uses list_add_tail(), and solved this issue.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The word to be transmitted/received via regmap is composed by the following
parts:
config->reg_bits
config->val_bits
config->pad_bits
,so the total size should be calculated by summing up the number of bits of
each element and using a DIV_ROUND_UP to return the number of bytes.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
If debugfs isn't cleaned up, stale files will be left in the filesystem
which will cause an OOPS when accessed the first time, and hang the
accessing application when accessed again, presumably due to some lock
being left held.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Pull vfs changes from Al Viro.
"A lot of misc stuff. The obvious groups:
* Miklos' atomic_open series; kills the damn abuse of
->d_revalidate() by NFS, which was the major stumbling block for
all work in that area.
* ripping security_file_mmap() and dealing with deadlocks in the
area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
general.
* ->encode_fh() switched to saner API; insane fake dentry in
mm/cleancache.c gone.
* assorted annotations in fs (endianness, __user)
* parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
* ->update_time() work from Josef.
* other bits and pieces all over the place.
Normally it would've been in two or three pull requests, but
signal.git stuff had eaten a lot of time during this cycle ;-/"
Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
nfs: don't open in ->d_revalidate
vfs: retry last component if opening stale dentry
vfs: nameidata_to_filp(): don't throw away file on error
vfs: nameidata_to_filp(): inline __dentry_open()
vfs: do_dentry_open(): don't put filp
vfs: split __dentry_open()
vfs: do_last() common post lookup
vfs: do_last(): add audit_inode before open
vfs: do_last(): only return EISDIR for O_CREAT
vfs: do_last(): check LOOKUP_DIRECTORY
vfs: do_last(): make ENOENT exit RCU safe
vfs: make follow_link check RCU safe
vfs: do_last(): use inode variable
vfs: do_last(): inline walk_component()
vfs: do_last(): make exit RCU safe
vfs: split do_lookup()
Btrfs: move over to use ->update_time
fs: introduce inode operation ->update_time
reiserfs: get rid of resierfs_sync_super
reiserfs: mark the superblock as dirty a bit later
...
Since there are uses for I2C_M_NOSTART which are much more sensible and
standard than most of the protocol mangling functionality (the main one
being gather writes to devices where something like a register address
needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART
for this feature and update all the users to use it.
Also strengthen the disrecommendation of the protocol mangling while we're
at it.
In the case of regmap-i2c we remove the requirement for mangling as
I2C_M_NOSTART is the only mangling feature which is being used.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
/sys/devices/system/node/{online,possible} outputs a garbage byte
because print_nodes_state() returns content size + 1. To fix the bug,
the patch changes the use of cpuset_sprintf_cpulist to follow the use at
other places, which is clearer and safer.
This bug was introduced in v2.6.24 (commit bde631a518: "mm: add node
states sysfs class attributeS").
Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'tag-for-linus-3.5' of git://git.linaro.org/people/sumitsemwal/linux-dma-buf
Pull dma-buf updates from Sumit Semwal:
"Here's the first signed-tag pull request for dma-buf framework. It
includes the following key items:
- mmap support
- vmap support
- related documentation updates
These are needed by various drivers to allow mmap/vmap of dma-buf
shared buffers. Dave Airlie has some prime patches dependent on the
vmap pull as well."
* tag 'tag-for-linus-3.5' of git://git.linaro.org/people/sumitsemwal/linux-dma-buf:
dma-buf: add initial vmap documentation
dma-buf: minor documentation fixes.
dma-buf: add vmap interface
dma-buf: mmap support
Pull CMA and ARM DMA-mapping updates from Marek Szyprowski:
"These patches contain two major updates for DMA mapping subsystem
(mainly for ARM architecture). First one is Contiguous Memory
Allocator (CMA) which makes it possible for device drivers to allocate
big contiguous chunks of memory after the system has booted.
The main difference from the similar frameworks is the fact that CMA
allows to transparently reuse the memory region reserved for the big
chunk allocation as a system memory, so no memory is wasted when no
big chunk is allocated. Once the alloc request is issued, the
framework migrates system pages to create space for the required big
chunk of physically contiguous memory.
For more information one can refer to nice LWN articles:
- 'A reworked contiguous memory allocator':
http://lwn.net/Articles/447405/
- 'CMA and ARM':
http://lwn.net/Articles/450286/
- 'A deep dive into CMA':
http://lwn.net/Articles/486301/
- and the following thread with the patches and links to all previous
versions:
https://lkml.org/lkml/2012/4/3/204
The main client for this new framework is ARM DMA-mapping subsystem.
The second part provides a complete redesign in ARM DMA-mapping
subsystem. The core implementation has been changed to use common
struct dma_map_ops based infrastructure with the recent updates for
new dma attributes merged in v3.4-rc2. This allows to use more than
one implementation of dma-mapping calls and change/select them on the
struct device basis. The first client of this new infractructure is
dmabounce implementation which has been completely cut out of the
core, common code.
The last patch of this redesign update introduces a new, experimental
implementation of dma-mapping calls on top of generic IOMMU framework.
This lets ARM sub-platform to transparently use IOMMU for DMA-mapping
calls if one provides required IOMMU hardware.
For more information please refer to the following thread:
http://www.spinics.net/lists/arm-kernel/msg175729.html
The last patch merges changes from both updates and provides a
resolution for the conflicts which cannot be avoided when patches have
been applied on the same files (mainly arch/arm/mm/dma-mapping.c)."
Acked by Andrew Morton <akpm@linux-foundation.org>:
"Yup, this one please. It's had much work, plenty of review and I
think even Russell is happy with it."
* 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: (28 commits)
ARM: dma-mapping: use PMD size for section unmap
cma: fix migration mode
ARM: integrate CMA with DMA-mapping subsystem
X86: integrate CMA with DMA-mapping subsystem
drivers: add Contiguous Memory Allocator
mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks
mm: extract reclaim code from __alloc_pages_direct_reclaim()
mm: Serialize access to min_free_kbytes
mm: page_isolation: MIGRATE_CMA isolation functions added
mm: mmzone: MIGRATE_CMA migration type added
mm: page_alloc: change fallbacks array handling
mm: page_alloc: introduce alloc_contig_range()
mm: compaction: export some of the functions
mm: compaction: introduce isolate_freepages_range()
mm: compaction: introduce map_pages()
mm: compaction: introduce isolate_migratepages_range()
mm: page_alloc: remove trailing whitespace
ARM: dma-mapping: add support for IOMMU mapper
ARM: dma-mapping: use alloc, mmap, free from dma_ops
ARM: dma-mapping: remove redundant code and do the cleanup
...
Conflicts:
arch/x86/include/asm/dma-mapping.h
Some minor inline documentation fixes for gaps resulting from new patches.
Signed-off-by: Sumit Semwal <sumit.semwal@ti.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
The main requirement I have for this interface is for scanning out
using the USB gpu devices. Since these devices have to read the
framebuffer on updates and linearly compress it, using kmaps
is a major overhead for every update.
v2: fix warn issues pointed out by Sylwester Nawrocki.
v3: fix compile !CONFIG_DMA_SHARED_BUFFER and add _GPL for now
Signed-off-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Rob Clark <rob.clark@linaro.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Compared to Rob Clark's RFC I've ditched the prepare/finish hooks
and corresponding ioctls on the dma_buf file. The major reason for
that is that many people seem to be under the impression that this is
also for synchronization with outstanding asynchronous processsing.
I'm pretty massively opposed to this because:
- It boils down reinventing a new rather general-purpose userspace
synchronization interface. If we look at things like futexes, this
is hard to get right.
- Furthermore a lot of kernel code has to interact with this
synchronization primitive. This smells a look like the dri1 hw_lock,
a horror show I prefer not to reinvent.
- Even more fun is that multiple different subsystems would interact
here, so we have plenty of opportunities to create funny deadlock
scenarios.
I think synchronization is a wholesale different problem from data
sharing and should be tackled as an orthogonal problem.
Now we could demand that prepare/finish may only ensure cache
coherency (as Rob intended), but that runs up into the next problem:
We not only need mmap support to facilitate sw-only processing nodes
in a pipeline (without jumping through hoops by importing the dma_buf
into some sw-access only importer), which allows for a nicer
ION->dma-buf upgrade path for existing Android userspace. We also need
mmap support for existing importing subsystems to support existing
userspace libraries. And a loot of these subsystems are expected to
export coherent userspace mappings.
So prepare/finish can only ever be optional and the exporter /needs/
to support coherent mappings. Given that mmap access is always
somewhat fallback-y in nature I've decided to drop this optimization,
instead of just making it optional. If we demonstrate a clear need for
this, supported by benchmark results, we can always add it in again
later as an optional extension.
Other differences compared to Rob's RFC is the above mentioned support
for mapping a dma-buf through facilities provided by the importer.
Which results in mmap support no longer being optional.
Note that this dma-buf mmap patch does _not_ support every possible
insanity an existing subsystem could pull of with mmap: Because it
does not allow to intercept pagefaults and shoot down ptes importing
subsystems can't add some magic of their own at these points (e.g. to
automatically synchronize with outstanding rendering or set up some
special resources). I've done a cursory read through a few mmap
implementions of various subsytems and I'm hopeful that we can avoid
this (and the complexity it'd bring with it).
Additonally I've extended the documentation a bit to explain the hows
and whys of this mmap extension.
In case we ever want to add support for explicitly cache maneged
userspace mmap with a prepare/finish ioctl pair, we could specify that
userspace needs to mmap a different part of the dma_buf, e.g. the
range starting at dma_buf->size up to dma_buf->size*2. This works
because the size of a dma_buf is invariant over it's lifetime. The
exporter would obviously need to fall back to coherent mappings for
both ranges if a legacy clients maps the coherent range and the
architecture cannot suppor conflicting caching policies. Also, this
would obviously be optional and userspace needs to be able to fall
back to coherent mappings.
v2:
- Spelling fixes from Rob Clark.
- Compile fix for !DMA_BUF from Rob Clark.
- Extend commit message to explain how explicitly cache managed mmap
support could be added later.
- Extend the documentation with implementations notes for exporters
that need to manually fake coherency.
v3:
- dma_buf pointer initialization goof-up noticed by Rebecca Schultz
Zavin.
Cc: Rob Clark <rob.clark@linaro.org>
Cc: Rebecca Schultz Zavin <rebecca@android.com>
Acked-by: Rob Clark <rob.clark@linaro.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
* Implementation of opportunistic suspend (autosleep) and user space interface
for manipulating wakeup sources.
* Hibernate updates from Bojan Smojver and Minho Ban.
* Updates of the runtime PM core and generic PM domains framework related to
PM QoS.
* Assorted fixes.
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Merge tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
- Implementation of opportunistic suspend (autosleep) and user space
interface for manipulating wakeup sources.
- Hibernate updates from Bojan Smojver and Minho Ban.
- Updates of the runtime PM core and generic PM domains framework
related to PM QoS.
- Assorted fixes.
* tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits)
epoll: Fix user space breakage related to EPOLLWAKEUP
PM / Domains: Make it possible to add devices to inactive domains
PM / Hibernate: Use get_gendisk to verify partition if resume_file is integer format
PM / Domains: Fix computation of maximum domain off time
PM / Domains: Fix link checking when add subdomain
PM / Sleep: User space wakeup sources garbage collector Kconfig option
PM / Sleep: Make the limit of user space wakeup sources configurable
PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
PM / Domains: Cache device stop and domain power off governor results, v3
PM / Domains: Make device removal more straightforward
PM / Sleep: Fix a mistake in a conditional in autosleep_store()
epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
PM / QoS: Create device constraints objects on notifier registration
PM / Runtime: Remove device fields related to suspend time, v2
PM / Domains: Rework default domain power off governor function, v2
PM / Domains: Rework default device stop governor function, v2
PM / Sleep: Add user space interface for manipulating wakeup sources, v3
PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
PM / Sleep: Implement opportunistic sleep, v2
PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
...
Fixes a missing select from the Palmas driver a bit more throoughly.
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Merge tag 'regmap-domain-deps' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull a regmap kconfig dependency fix from Mark Brown:
"Fix the dependency on IRQ_DOMAIN for REGMAP_IRQ in the core
Fixes a missing select from the Palmas driver a bit more throoughly."
* tag 'regmap-domain-deps' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: Use select .. if to get IRQ_DOMAIN enabled
Ensure that we can't get randconfig breakage by doing the IRQ_DOMAIN
select automatically. Don't just do the select from REGMAP_IRQ to ensure
that the select actually gets noticed.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Pull scheduler changes from Ingo Molnar:
"The biggest change is the cleanup/simplification of the load-balancer:
instead of the current practice of architectures twiddling scheduler
internal data structures and providing the scheduler domains in
colorfully inconsistent ways, we now have generic scheduler code in
kernel/sched/core.c:sched_init_numa() that looks at the architecture's
node_distance() parameters and (while not fully trusting it) deducts a
NUMA topology from it.
This inevitably changes balancing behavior - hopefully for the better.
There are various smaller optimizations, cleanups and fixlets as well"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Taint kernel with TAINT_WARN after sleep-in-atomic bug
sched: Remove stale power aware scheduling remnants and dysfunctional knobs
sched/debug: Fix printing large integers on 32-bit platforms
sched/fair: Improve the ->group_imb logic
sched/nohz: Fix rq->cpu_load[] calculations
sched/numa: Don't scale the imbalance
sched/fair: Revert sched-domain iteration breakage
sched/x86: Rewrite set_cpu_sibling_map()
sched/numa: Fix the new NUMA topology bits
sched/numa: Rewrite the CONFIG_NUMA sched domain support
sched/fair: Propagate 'struct lb_env' usage into find_busiest_group
sched/fair: Add some serialization to the sched_domain load-balance walk
sched/fair: Let minimally loaded cpu balance the group
sched: Change rq->nr_running to unsigned int
x86/numa: Check for nonsensical topologies on real hw as well
x86/numa: Hard partition cpu topology masks on node boundaries
x86/numa: Allow specifying node_distance() for numa=fake
x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properly
sched: Update documentation and comments
sched_rt: Avoid unnecessary dequeue and enqueue of pushable tasks in set_cpus_allowed_rt()
Here's the driver core, and other driver subsystems, pull request for
the 3.5-rc1 merge window.
Outside of a few minor driver core changes, we ended up with the
following different subsystem and core changes as well, due to
interdependancies on the driver core:
- hyperv driver updates
- drivers/memory being created and some drivers moved into it
- extcon driver subsystem created out of the old Android staging switch
driver code
- dynamic debug updates
- printk rework, and /dev/kmsg changes
All of this has been tested in the linux-next releases for a few weeks
with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg Kroah-Hartman:
"Here's the driver core, and other driver subsystems, pull request for
the 3.5-rc1 merge window.
Outside of a few minor driver core changes, we ended up with the
following different subsystem and core changes as well, due to
interdependancies on the driver core:
- hyperv driver updates
- drivers/memory being created and some drivers moved into it
- extcon driver subsystem created out of the old Android staging
switch driver code
- dynamic debug updates
- printk rework, and /dev/kmsg changes
All of this has been tested in the linux-next releases for a few weeks
with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
Fix up conflicts in drivers/extcon/extcon-max8997.c where git noticed
that a patch to the deleted drivers/misc/max8997-muic.c driver needs to
be applied to this one.
* tag 'driver-core-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (90 commits)
uio_pdrv_genirq: get irq through platform resource if not set otherwise
memory: tegra{20,30}-mc: Remove empty *_remove()
printk() - isolate KERN_CONT users from ordinary complete lines
sysfs: get rid of some lockdep false positives
Drivers: hv: util: Properly handle version negotiations.
Drivers: hv: Get rid of an unnecessary check in vmbus_prep_negotiate_resp()
memory: tegra{20,30}-mc: Use dev_err_ratelimited()
driver core: Add dev_*_ratelimited() family
Driver Core: don't oops with unregistered driver in driver_find_device()
printk() - restore prefix/timestamp printing for multi-newline strings
printk: add stub for prepend_timestamp()
ARM: tegra30: Make MC optional in Kconfig
ARM: tegra20: Make MC optional in Kconfig
ARM: tegra30: MC: Remove unnecessary BUG*()
ARM: tegra20: MC: Remove unnecessary BUG*()
printk: correctly align __log_buf
ARM: tegra30: Add Tegra Memory Controller(MC) driver
ARM: tegra20: Add Tegra Memory Controller(MC) driver
printk() - restore timestamp printing at console output
printk() - do not merge continuation lines of different threads
...
The Contiguous Memory Allocator is a set of helper functions for DMA
mapping framework that improves allocations of contiguous memory chunks.
CMA grabs memory on system boot, marks it with MIGRATE_CMA migrate type
and gives back to the system. Kernel is allowed to allocate only movable
pages within CMA's managed memory so that it can be used for example for
page cache when DMA mapping do not use it. On
dma_alloc_from_contiguous() request such pages are migrated out of CMA
area to free required contiguous block and fulfill the request. This
allows to allocate large contiguous chunks of memory at any time
assuming that there is enough free memory available in the system.
This code is heavily based on earlier works by Michal Nazarewicz.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
Add a common helper for dma-mapping core for mapping a coherent buffer
to userspace.
Reported-by: Subash Patel <subashrp@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
The generic PM domains core code currently requires domains to be in
the "power on" state for adding devices to them, but this limitation
turns out to be inconvenient in some situations, so remove it.
For this purpose, make __pm_genpd_add_device() set the device's
need_restore flag if the domain is in the "power off" state, so that
the device's "restore state" (usually .runtime_resume()) callback
is executed when it is resumed after the domain has been turned on.
If the domain is in the "power on" state, the device's need_restore
flag will be cleared by __pm_genpd_add_device(), so that its "save
state" (usually .runtime_suspend()) callback is executed when the
domain is about to be turned off. However, since that default
behavior need not be always desirable, add a helper function
pm_genpd_dev_need_restore() allowing a device's need_restore flag
to be set/unset at any time.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.
There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.
Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.
So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.
There is a proposal to replace the user interface with a single
3 state knob:
sched_balance_policy := { performance, power, auto }
where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.
Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.
Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In some chips the IRQ status registers are not contiguous in the register
map but spaced at even spaces. This is an easy case to handle with minor
changes. It is assume for this purpose that the stride for status is
equal to the stride for mask/ack registers as well.
Signed-off-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
driver_find_device() can be called with an unregistered driver. Need
to check driver_private to see if it's populated or not, especially
under deferrable probe.
In the case that there are 2 drivers, one depends on the other. With
-EPROBE_DEFER, two drivers can use deferred probe to ensure that their
relative probe order doesn't matter. If dependee driver is probed
first, then the dependant's driver_find_device('dependee')
succeeds. If the dependant is probed first, then the dependant's
driver_find_device('dependee') should return NULL, and the dependant
should get -EPROBE_DEFER. driver_find_device() needs to return NULL if
it's not populated.
In [PATCHv5 2/3] ARM: tegra: Add SMMU enabler in AHB:
http://article.gmane.org/gmane.linux.ports.tegra/4658
"tegra_ahb_driver" may not be populated when it's called.
For more SMMU/AHB specific discussion, refer to the following thread:
https://lkml.org/lkml/2012/5/10/21
Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This gets us up to date with the recommended current kernel infrastructure
and should transparently give us device tree interrupt bindings for any
devices using the framework. If an explicit IRQ mapping is passed in then
a legacy interrupt range is created, otherwise a simple linear mapping is
used. Previously a mapping was mandatory so existing drivers should not
be affected.
A function regmap_irq_get_virq() is provided to allow drivers to map
individual IRQs which should be used in preference to the existing
regmap_irq_chip_get_base() which is only valid if a legacy IRQ range is
provided.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used. The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.
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Merge tag 'regmap-3.4' into regmap-stride
regmap: Last minute bug fix for 3.4
This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used. The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.
Conflicts:
drivers/base/regmap/regmap.c (overlap between the fix and stride code)
* pm-sleep:
PM / Sleep: User space wakeup sources garbage collector Kconfig option
PM / Sleep: Make the limit of user space wakeup sources configurable
PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
PM / Sleep: Fix a mistake in a conditional in autosleep_store()
epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
PM / Sleep: Add user space interface for manipulating wakeup sources, v3
PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
PM / Sleep: Implement opportunistic sleep, v2
PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
PM / Sleep: Change wakeup source statistics to follow Android
PM / Sleep: Use wait queue to signal "no wakeup events in progress"
PM / Sleep: Look for wakeup events in later stages of device suspend
PM / Hibernate: Hibernate/thaw fixes/improvements
The default domain power off governor function for generic PM
domains, default_power_down_ok(), may violate subdomain maximum
off time limit by allowing the master domain to be off for too
long. Namely, it only finds the minium of all device maximum
off times over the domain's devices and uses that to compute the
domain's maximum off time, but it should do the same for the
subdomains.
Fix this problem by modifying default_power_down_ok() to compute
the given domain's maximum off time as the difference between the
minimum off time over all devices and subdomains in the domain and
its power on latency.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Current pm_genpd_add_subdomain() will allow duplicated link between
master and slave domain. This patch fixed it.
Because when current pm_genpd_add_subdomain() checks whether the link
between the master and slave generic PM domain already exists,
slave_links instead of master_links of master domain is used.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The function regmap_bulk_read() calls the regmap_read() for
each register if set of register has volatile and cache is
enabled. In this case, last few register read makes the memory
corruption if the register size is not the size of unsigned int.
The regam_read() takes argument as unsigned int for returning
value and it update the value as
*val = map->format.parse_val(map->work_buf);
This causes complete 4 bytes (size of unsigned int) to get written.
Now if client pass the memory pointer for value which is equal to the
required size of register count in regmap_bulk_read() then last few
register read actually update the memory beyond passed pointer size.
Avoid this by using local variable for read and then do memcpy()
for actual byte copy to passed pointer based on register size.
I allocated one pointer ptr and take first 16 bytes dump of that
pointer then call regmap_bulk_read() with pointer which is just
on top of this allocated pointer and register count of 128. Here
register size is 1 byte.
The memory trace of last 5 register read are as follows:
[ 5.438589] regmap_bulk_read after regamp_read() for register 122
[ 5.447421] 0xef993c20 0xef993c00 0x00000000 0x00000001
[ 5.467535] regmap_bulk_read after regamp_read() for register 123
[ 5.476374] 0xef993c20 0xef993c00 0x00000000 0x00000001
[ 5.496425] regmap_bulk_read after regamp_read() for register 124
[ 5.505260] 0xef993c20 0xef993c00 0x00000000 0x00000001
[ 5.525372] regmap_bulk_read after regamp_read() for register 125
[ 5.534205] 0xef993c00 0xef993c00 0x00000000 0x00000001
[ 5.554258] regmap_bulk_read after regamp_read() for register 126
[ 5.563100] 0xef990000 0xef993c00 0x00000000 0x00000001
[ 5.554258] regmap_bulk_read after regamp_read() for register 127
[ 5.587108] 0xef000000 0xef993c00 0x00000000 0x00000001
Here it is observed that the memory content at first word started changing
on last 3 regmap_read() and so corruption happened.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Use devres to implement dev_get_regmap(). This should mean that in almost
all cases devices wishing to take advantage of framework features based on
regmap shouldn't need to explicitly pass the regmap into the framework.
This simplifies device setup a bit.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Extends dev_printk() to attach a dictionary with a device identifier
and the driver core subsystem name to logged messages, which makes
dev_prink() reliable machine-readable. In addition to the printed
plain text message, it creates these properties:
SUBSYSTEM= - the driver-core subsytem name
DEVICE=
b12:8 - block dev_t
c127:3 - char dev_t
n8 - netdev ifindex
+sound:card0 - subsystem:devname
Tested-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The results of the default device stop and domain power off governor
functions for generic PM domains, default_stop_ok() and
default_power_down_ok(), depend only on the timing data of devices,
which are static, and on their PM QoS constraints. Thus, in theory,
these functions only need to carry out their computations, which may
be time consuming in general, when it is known that the PM QoS
constraint of at least one of the devices in question has changed.
Use the PM QoS notifiers of devices to implement that. First,
introduce new fields, constraint_changed and max_off_time_changed,
into struct gpd_timing_data and struct generic_pm_domain,
respectively, and register a PM QoS notifier function when adding
a device into a domain that will set those fields to 'true' whenever
the device's PM QoS constraint is modified. Second, make
default_stop_ok() and default_power_down_ok() use those fields to
decide whether or not to carry out their computations from scratch.
The device and PM domain hierarchies are taken into account in that
and the expense is that the changes of PM QoS constraints of
suspended devices will not be taken into account immediately, which
isn't guaranteed anyway in general.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The removal of a device from a PM domain doesn't have to browse
the domain's device list, because it can check directly if the
device belongs to the given domain. Moreover, it should clear
the domain_data pointer in dev->power.subsys_data, because
dev_pm_put_subsys_data(dev) may not remove dev->power.subsys_data
and the stale domain data pointer may cause problems to happen.
Rework pm_genpd_remove_device() taking the above observations into
account.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
APIs using devres frequently want to implement a "remove and free the
resource" operation so it seems sensible that they should be able to
just have devres do the freeing for them since that's a big part of what
devres is all about.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's not massively obvious (at least to me) that removing and freeing a
resource does not involve calling the release function for the resource
but rather only removes the management of it. Make the documentation more
explicit.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This was done to resolve a merge issue with the init/main.c file.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current behavior of dev_pm_qos_add_notifier() makes device PM QoS
notifiers less than useful. Namely, it silently returns success when
called before any PM QoS constraints are added for the device, so the
caller will assume that the notifier has been registered, but when
someone actually adds some nontrivial constraints for the device
eventually, the previous callers of dev_pm_qos_add_notifier()
will not know about that and their notifier routines will not be
executed (contrary to their expectations).
To address this problem make dev_pm_qos_add_notifier() create the
constraints object for the device if it is not present when the
routine is called.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by : markgross <markgross@thegnar.org>
After the previous changes in default_stop_ok() and
default_power_down_ok() for PM domains, there are two fields in
struct dev_pm_info that aren't necessary any more, suspend_time
and max_time_suspended_ns.
Remove those fields along with all of the code that accesses them,
which simplifies the runtime PM framework quite a bit.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The existing default domain power down governor function for PM
domains, default_power_down_ok(), is supposed to check whether or not
the PM QoS latency constraints of the devices in the domain will be
violated if the domain is turned off by pm_genpd_poweroff().
However, the computations carried out by it don't reflect the
definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.
Make default_power_down_ok() follow the definition of the PM QoS
latency constrait. In particular, make it only take latencies into
account, because it doesn't matter how much time has elapsed since
the domain's devices were suspended for the computation.
Remove the break_even_ns and power_off_time fields from
struct generic_pm_domain, because they are not necessary any more.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The existing default device stop governor function for PM domains,
default_stop_ok(), is supposed to check whether or not the device's
PM QoS latency constraint will be violated if the device is stopped
by pm_genpd_runtime_suspend(). However, the computations carried out
by it don't reflect the definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.
Make default_stop_ok() follow the definition of the PM QoS latency
constrait. In particular, make it take the device's start and stop
latencies correctly.
Add a new field, effective_constraint_ns, to struct gpd_timing_data
and use it to store the difference between the device's PM QoS
constraint and its resume latency for use by the device's parent
(the effective_constraint_ns values for the children are used for
computing the parent's one along with its PM QoS constraint).
Remove the break_even_ns field from struct gpd_timing_data, because
it's not used any more.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Android allows user space to manipulate wakelocks using two
sysfs file located in /sys/power/, wake_lock and wake_unlock.
Writing a wakelock name and optionally a timeout to the wake_lock
file causes the wakelock whose name was written to be acquired (it
is created before is necessary), optionally with the given timeout.
Writing the name of a wakelock to wake_unlock causes that wakelock
to be released.
Implement an analogous interface for user space using wakeup sources.
Add the /sys/power/wake_lock and /sys/power/wake_unlock files
allowing user space to create, activate and deactivate wakeup
sources, such that writing a name and optionally a timeout to
wake_lock causes the wakeup source of that name to be activated,
optionally with the given timeout. If that wakeup source doesn't
exist, it will be created and then activated. Writing a name to
wake_unlock causes the wakeup source of that name, if there is one,
to be deactivated. Wakeup sources created with the help of
wake_lock that haven't been used for more than 5 minutes are garbage
collected and destroyed. Moreover, there can be only WL_NUMBER_LIMIT
wakeup sources created with the help of wake_lock present at a time.
The data type used to track wakeup sources created by user space is
called "struct wakelock" to indicate the origins of this feature.
This version of the patch includes an rbtree manipulation fix from John Stultz.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NeilBrown <neilb@suse.de>
