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