07 Jul, 2016

1 commit


21 May, 2016

1 commit

  • 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: c6400ba7e13a ("drivers/hwspinlock: fix race between radix tree insertion and lookup")
    Signed-off-by: Matthew Wilcox
    Cc: Konstantin Khlebnikov
    Cc: Kirill Shutemov
    Cc: Jan Kara
    Cc: Neil Brown
    Cc: Ross Zwisler
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Matthew Wilcox
     

04 Feb, 2016

1 commit

  • 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
    Cc: Hugh Dickins
    Cc: Ohad Ben-Cohen
    Cc: Konstantin Khlebnikov
    Cc:
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Matthew Wilcox
     

01 Jul, 2015

1 commit


12 Jun, 2015

1 commit

  • 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
    Reviewed-by: Bjorn Andersson
    Signed-off-by: Wei Chen
    Signed-off-by: Barry Song
    Signed-off-by: Ohad Ben-Cohen

    Wei Chen
     

02 May, 2015

3 commits

  • Add driver for Qualcomm Hardware Mutex block found in many Qualcomm
    SoCs.

    Based on initial effort by Kumar Gala

    Signed-off-by: Bjorn Andersson
    Reviewed-by: Andy Gross
    Reviewed-by: Jeffrey Hugo
    Signed-off-by: Ohad Ben-Cohen

    Bjorn Andersson
     
  • 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
    [tony@atomide.com: ack for legacy file removal]
    Acked-by: Tony Lindgren
    [comment on the imperfect always-zero base_id]
    Signed-off-by: Ohad Ben-Cohen

    Suman Anna
     
  • 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
    Reviewed-by: Bjorn Andersson
    [small comment clarification]
    Signed-off-by: Ohad Ben-Cohen

    Suman Anna
     

20 Oct, 2014

1 commit


29 Jul, 2014

2 commits

  • 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
    [small commit log changes]
    Signed-off-by: Ohad Ben-Cohen

    Suman Anna
     
  • 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
    [replace pm_runtime_put_sync with lenient pm_runtime_put]
    Signed-off-by: Ohad Ben-Cohen

    Suman Anna
     

08 May, 2013

1 commit


05 Apr, 2013

2 commits

  • 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
    Signed-off-by: Li Fei
    [edit commit log]
    Signed-off-by: Ohad Ben-Cohen

    Li Fei
     
  • OMAP5 has spinlocks, too.

    Signed-off-by: Vincent Stehlé
    Cc: Tony Lindgren
    Signed-off-by: Ohad Ben-Cohen

    Vincent Stehlé
     

29 Nov, 2012

3 commits


10 Sep, 2012

1 commit


08 Jul, 2012

1 commit

  • 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
    Signed-off-by: Shinya Kuribayashi
    [ohad: fix error path of hwspin_lock_register, too]
    Signed-off-by: Ohad Ben-Cohen

    Shinya Kuribayashi
     

09 Nov, 2011

1 commit


08 Nov, 2011

2 commits

  • 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
    Signed-off-by: Ohad Ben-Cohen

    Axel Lin
     
  • 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
    Signed-off-by: Paul Gortmaker

    Axel Lin
     

22 Sep, 2011

8 commits

  • 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 Ben-Cohen
     
  • 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
    Acked-by: Linus Walleij
    [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

    Mathieu J. Poirier
     
  • 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 Ben-Cohen
     
  • 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:
    Signed-off-by: Juan Gutierrez
    [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

    Juan Gutierrez
     
  • 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
    Signed-off-by: Ohad Ben-Cohen
    Acked-by: Tony Lindgren

    Ohad Ben-Cohen
     
  • 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
    Signed-off-by: Ohad Ben-Cohen

    Ohad Ben-Cohen
     
  • 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 Ben-Cohen
     
  • 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 Ben-Cohen
     

19 Mar, 2011

1 commit


18 Feb, 2011

2 commits

  • 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
    Signed-off-by: Hari Kanigeri
    Signed-off-by: Krishnamoorthy, Balaji T
    Signed-off-by: Ohad Ben-Cohen
    Cc: Benoit Cousson
    Cc: Kevin Hilman
    Cc: Grant Likely
    Cc: Arnd Bergmann
    Cc: Paul Walmsley
    Cc: Russell King
    Signed-off-by: Tony Lindgren

    Simon Que
     
  • 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
    Cc: Hari Kanigeri
    Cc: Benoit Cousson
    Cc: Kevin Hilman
    Cc: Grant Likely
    Cc: Paul Walmsley
    Cc: Russell King
    Acked-by: Arnd Bergmann
    Signed-off-by: Tony Lindgren

    Ohad Ben-Cohen