Use the appropriate SPDX license identifier in the CSR's SIRF hardware
spinlock driver source file and drop the previous boilerplate license text.
Cc: Wei Chen <wei.chen@csr.com>
Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Use the appropriate SPDX license identifier in the Qualcomm Hwspinlock
driver source file and drop the previous boilerplate license text.
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Use the appropriate SPDX license identifier in the OMAP hwspinlock
driver source file and drop the previous boilerplate license text.
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Use the appropriate SPDX license identifier in the Hwspinlock core
driver source files and drop the previous boilerplate license text.
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
In some scenarios, user need do some time-consuming or sleepable
operations under the hardware spinlock protection for synchronization
between the multiple subsystems.
For example, there is one PMIC efuse on Spreadtrum platform, which
need to be accessed under one hardware lock. But during the hardware
lock protection, the efuse operation is time-consuming to almost 5 ms,
so we can not disable the interrupts or preemption so long in this case.
Thus we can introduce one new mode to indicate that we just acquire the
hardware lock and do not disable interrupts or preemption, meanwhile we
should force user to protect the hardware lock with mutex or spinlock to
avoid dead-lock.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
We have different hwspinlock modes to select, thus it will be more
readable to handle different modes with using 'switch' statement
instead of 'if' statement.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
This changes the HWSPINLOCK core Kconfig option to bool, to aid when other core
code depends on it.
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Merge tag 'hwlock-v4.15' of git://github.com/andersson/remoteproc
Pull hwspinlock update from Bjorn Andersson:
"This changes the HWSPINLOCK core Kconfig option to bool, to aid when
other core code depends on it"
* tag 'hwlock-v4.15' of git://github.com/andersson/remoteproc:
hwspinlock: Change hwspinlock to a bool
Change hwspinlock to a bool in case some drivers will meet dependency
issue when hwspinlock is built as a module.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Spreadtrum hardware spinlock device can provide hardware assistance
for synchronization between the multiple subsystems.
Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
So that there's no need to get into the submenu to disable all related config
entries.
Signed-off-by: Vincent Legoll <vincent.legoll@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
radix_tree_is_indirect_ptr() is an internal API. The correct call to
use is radix_tree_deref_retry() which has the appropriate unlikely()
annotation.
Fixes: c6400ba7e1 ("drivers/hwspinlock: fix race between radix tree insertion and lookup")
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Jan Kara <jack@suse.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
of_hwspin_lock_get_id() is protected by the RCU lock, which means that
insertions can occur simultaneously with the lookup. If the radix tree
transitions from a height of 0, we can see a slot with the indirect_ptr
bit set, which will cause us to at least read random memory, and could
cause other havoc.
Fix this by using the newly introduced radix_tree_iter_retry().
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
msb of the regmap_field was mistakenly given the value 32, to set all bits
in the regmap update mask; although incorrect this worked until 921cc294,
where the mask calculation was corrected.
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Add hwspinlock support for the CSR atlas7 SoC.
The Hardware Spinlock device on atlas7 provides hardware assistance
for synchronization between the multiple processors in the system
(dual Cortex-A7, CAN bus Cortex-M3 and audio DSP).
Reviewed-by: Suman Anna <s-anna@ti.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Wei Chen <wei.chen@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Add driver for Qualcomm Hardware Mutex block found in many Qualcomm
SoCs.
Based on initial effort by Kumar Gala <galak@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Reviewed-by: Andy Gross <agross@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
HwSpinlock IP is present only on OMAP4 and other newer SoCs,
which are all device-tree boot only. This patch adds the
base support for parsing the DT nodes, and removes the code
dealing with the traditional platform device instantiation.
Signed-off-by: Suman Anna <s-anna@ti.com>
[tony@atomide.com: ack for legacy file removal]
Acked-by: Tony Lindgren <tony@atomide.com>
[comment on the imperfect always-zero base_id]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
This patch adds a new OF-friendly API of_hwspin_lock_get_id()
for hwspinlock clients to use/request locks from a hwspinlock
device instantiated through a device-tree blob. This new API
can be used by hwspinlock clients to get the id for a specific
lock using the phandle + args specifier, so that it can be
requested using the available hwspin_lock_request_specific()
API.
Signed-off-by: Suman Anna <s-anna@ti.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
[small comment clarification]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
HwSpinlocks are supported on TI's AM33xx, AM43xx and DRA7xx SoC
device families as well. The IPs are identical to that of
OMAP4/OMAP5, except for the number of locks.
Add a depends on to the above family of SoCs to enable the
build support for OMAP hwspinlock driver for any of the above
SoC configs.
Signed-off-by: Suman Anna <s-anna@ti.com>
[small commit log changes]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
The number of hwspinlocks are determined based on the value read
from the IP block's SYSSTATUS register. However, the module may
not be enabled and clocked, and the read may result in a bus error.
This particular issue is seen rather easily on AM33XX, since the
module wakeup is software controlled, and it is disabled out of
reset. Make sure the module is enabled and clocked before reading
the SYSSTATUS register.
Signed-off-by: Suman Anna <s-anna@ti.com>
[replace pm_runtime_put_sync with lenient pm_runtime_put]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
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Merge tag 'hwspinlock-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock
Pullhwspinlock update from Ohad Ben-Cohen:
"A single patch from Vincent extending OMAP's hwspinlock support to
OMAP5"
* tag 'hwspinlock-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock:
hwspinlock/omap: support OMAP5 as well
Even in failed case of pm_runtime_get_sync, the usage_count
is incremented. In order to keep the usage_count with correct
value and runtime power management to behave correctly, call
pm_runtime_put_noidle in such case.
In __hwspin_lock_request, module_put is also called before
return in pm_runtime_get_sync failed case.
Cc: stable@vger.kernel.org
Signed-off-by Liu Chuansheng <chuansheng.liu@intel.com>
Signed-off-by: Li Fei <fei.li@intel.com>
[edit commit log]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dereference should be moved below the NULL test.
spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Commit 300bab9770 (hwspinlock/core: register a bank of hwspinlocks in a
single API call, 2011-09-06) introduced 'hwspin_lock_register_single()'
to register numerous (a bank of) hwspinlock instances in a single API,
'hwspin_lock_register()'.
At which time, 'hwspin_lock_register()' accidentally passes 'local IDs'
to 'hwspin_lock_register_single()', despite that ..._single() requires
'global IDs' to register hwspinlocks.
We have to convert into global IDs by supplying the missing 'base_id'.
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
[ohad: fix error path of hwspin_lock_register, too]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
drivers/media: video/a5k6aa is a module and so needs module.h
mfd: fix build failures in recently added ab5500 code
hwspinlock/u8500: include linux/module.h
MTD: MAPS: bcm963xx-flash.c: explicitly include module.h
Fix below build error:
CC drivers/hwspinlock/u8500_hsem.o
drivers/hwspinlock/u8500_hsem.c: In function 'u8500_hsem_probe':
drivers/hwspinlock/u8500_hsem.c:113: error: label 'free_state' used but not defined
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Include module.h to fix below build error:
CC drivers/hwspinlock/u8500_hsem.o
drivers/hwspinlock/u8500_hsem.c:177: error: 'THIS_MODULE' undeclared here (not in a function)
[...]
drivers/hwspinlock/u8500_hsem.c:196: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR'
drivers/hwspinlock/u8500_hsem.c:196: warning: function declaration isn't a prototype
make[2]: *** [drivers/hwspinlock/u8500_hsem.o] Error 1
make[1]: *** [drivers/hwspinlock] Error 2
make: *** [drivers] Error 2
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Mark omap_hwspinlock_remove with __devexit (and use __devexit_p
appropriately) so the function can be discarded when the conditions are met.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Add hwspinlock driver for U8500's Hsem hardware.
At this point only HSem's protocol 1 is used (i.e. no interrupts).
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
[ohad@wizery.com: adopt recent hwspin_lock_{un}register API changes]
[ohad@wizery.com: set the owner member of the driver]
[ohad@wizery.com: mark ->remove() function as __devexit]
[ohad@wizery.com: write commit log]
[ohad@wizery.com: small cleanups]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Hardware Spinlock devices usually contain numerous locks (known
devices today support between 32 to 256 locks).
Originally hwspinlock core required drivers to register (and later,
when needed, unregister) each lock separately.
That worked, but required hwspinlocks drivers to do a bit extra work
when they were probed/removed.
This patch changes hwspin_lock_{un}register() to allow a bank of
hwspinlocks to be {un}registered in a single invocation.
A new 'struct hwspinlock_device', which contains an array of 'struct
hwspinlock's is now being passed to the core upon registration (so
instead of wrapping each struct hwspinlock, a priv member has been added
to allow drivers to piggyback their private data with each hwspinlock).
While at it, several per-lock members were moved to be per-device:
1. struct device *dev
2. struct hwspinlock_ops *ops
In addition, now that the array of locks is handled by the core,
there's no reason to maintain a per-lock 'int id' member: the id of the
lock anyway equals to its index in the bank's array plus the bank's
base_id.
Remove this per-lock id member too, and instead use a simple pointers
arithmetic to derive it.
As a result of this change, hwspinlocks drivers are now simpler and smaller
(about %20 code reduction) and the memory footprint of the hwspinlock
framework is reduced.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Since we're using non-atomic radix tree allocations, we
should be protecting the tree using a mutex and not a
spinlock.
Non-atomic allocations and process context locking is good enough,
as the tree is manipulated only when locks are registered/
unregistered/requested/freed.
The locks themselves are still protected by spinlocks of course,
and mutexes are not involved in the locking/unlocking paths.
Cc: <stable@kernel.org>
Signed-off-by: Juan Gutierrez <jgutierrez@ti.com>
[ohad@wizery.com: rewrite the commit log, #include mutex.h, add minor
commentary]
[ohad@wizery.com: update register/unregister parts in hwspinlock.txt]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
hwspinlock devices provide system-wide hardware locks that are used
by remote processors that have no other way to achieve synchronization.
To achieve that, each physical lock must have a system-wide id number
that is agreed upon, otherwise remote processors can't possibly assume
they're using the same hardware lock.
Usually boards have a single hwspinlock device, which provides several
hwspinlocks, and in this case, they can be trivially numbered 0 to
(num-of-locks - 1).
In case boards have several hwspinlocks devices, a different base id
should be used for each hwspinlock device (they can't all use 0 as
a starting id!).
While this is certainly not common, it's just plain wrong to just
silently use 0 as a base id whenever the hwspinlock driver is probed.
This patch provides a hwspinlock_pdata structure, that boards can use
to set a different base id for each of the hwspinlock devices they may
have, and demonstrates how to use it with the omap hwspinlock driver.
While we're at it, make sure the hwspinlock core prints an explicit
error message in case an hwspinlock is registered with an id number
that already exists; this will help users catch such base id issues.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Instead of allocating every hwspinlock separately, allocate
them all in one shot.
This both simplifies the driver and helps achieving better
slab utilization.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Use struct device_driver's owner member instead of asking drivers to
explicitly pass the owner again.
This simplifies drivers and also save some memory, since there's no
point now in maintaining a separate owner pointer per hwspinlock.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Simplify hwspinlock's Kconfig by making the global CONFIG_HWSPINLOCK
entry invisible; users will just select it when needed.
This also prepares the ground for adding hwspinlock support for other
platforms (the 'depends on ARCH_OMAP4' was rather hideous, and while
we're at it, a dedicated menu is added).
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Currently only OMAP4 supports hwspinlocks, so don't bother asking
anyone else.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Add hwspinlock support for the OMAP4 Hardware Spinlock device.
The Hardware Spinlock device on OMAP4 provides hardware assistance
for synchronization between the multiple processors in the system
(dual Cortex-A9, dual Cortex-M3 and a C64x+ DSP).
[ohad@wizery.com: adapt to hwspinlock framework, tidy up]
Signed-off-by: Simon Que <sque@ti.com>
Signed-off-by: Hari Kanigeri <h-kanigeri2@ti.com>
Signed-off-by: Krishnamoorthy, Balaji T <balajitk@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Add a platform-independent hwspinlock framework.
Hardware spinlock devices are needed, e.g., in order to access data
that is shared between remote processors, that otherwise have no
alternative mechanism to accomplish synchronization and mutual exclusion
operations.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Hari Kanigeri <h-kanigeri2@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
