You've already forked linux-apfs
mirror of
https://github.com/linux-apfs/linux-apfs.git
synced 2026-05-01 15:00:59 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock: hwspinlock: add MAINTAINERS entries hwspinlock/omap: omap_hwspinlock_remove should be __devexit hwspinlock/u8500: add hwspinlock driver hwspinlock/core: register a bank of hwspinlocks in a single API call hwspinlock/core: remove stubs for register/unregister hwspinlock/core: use a mutex to protect the radix tree hwspinlock/core/omap: fix id issues on multiple hwspinlock devices hwspinlock/omap: simplify allocation scheme hwspinlock/core: simplify 'owner' handling hwspinlock/core: simplify Kconfig Fix up trivial conflicts (addition of omap_hwspinlock_pdata, removal of omap_spinlock_latency) in arch/arm/mach-omap2/hwspinlock.c Also, do an "evil merge" to fix a compile error in omap_hsmmc.c which for some reason was reported in the same email thread as the "please pull hwspinlock changes".
This commit is contained in:
@@ -39,23 +39,20 @@ independent, drivers.
|
||||
in case an unused hwspinlock isn't available. Users of this
|
||||
API will usually want to communicate the lock's id to the remote core
|
||||
before it can be used to achieve synchronization.
|
||||
Can be called from an atomic context (this function will not sleep) but
|
||||
not from within interrupt context.
|
||||
Should be called from a process context (might sleep).
|
||||
|
||||
struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
|
||||
- assign a specific hwspinlock id and return its address, or NULL
|
||||
if that hwspinlock is already in use. Usually board code will
|
||||
be calling this function in order to reserve specific hwspinlock
|
||||
ids for predefined purposes.
|
||||
Can be called from an atomic context (this function will not sleep) but
|
||||
not from within interrupt context.
|
||||
Should be called from a process context (might sleep).
|
||||
|
||||
int hwspin_lock_free(struct hwspinlock *hwlock);
|
||||
- free a previously-assigned hwspinlock; returns 0 on success, or an
|
||||
appropriate error code on failure (e.g. -EINVAL if the hwspinlock
|
||||
is already free).
|
||||
Can be called from an atomic context (this function will not sleep) but
|
||||
not from within interrupt context.
|
||||
Should be called from a process context (might sleep).
|
||||
|
||||
int hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int timeout);
|
||||
- lock a previously-assigned hwspinlock with a timeout limit (specified in
|
||||
@@ -230,45 +227,62 @@ int hwspinlock_example2(void)
|
||||
|
||||
4. API for implementors
|
||||
|
||||
int hwspin_lock_register(struct hwspinlock *hwlock);
|
||||
int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
|
||||
const struct hwspinlock_ops *ops, int base_id, int num_locks);
|
||||
- to be called from the underlying platform-specific implementation, in
|
||||
order to register a new hwspinlock instance. Can be called from an atomic
|
||||
context (this function will not sleep) but not from within interrupt
|
||||
context. Returns 0 on success, or appropriate error code on failure.
|
||||
order to register a new hwspinlock device (which is usually a bank of
|
||||
numerous locks). Should be called from a process context (this function
|
||||
might sleep).
|
||||
Returns 0 on success, or appropriate error code on failure.
|
||||
|
||||
struct hwspinlock *hwspin_lock_unregister(unsigned int id);
|
||||
int hwspin_lock_unregister(struct hwspinlock_device *bank);
|
||||
- to be called from the underlying vendor-specific implementation, in order
|
||||
to unregister an existing (and unused) hwspinlock instance.
|
||||
Can be called from an atomic context (will not sleep) but not from
|
||||
within interrupt context.
|
||||
to unregister an hwspinlock device (which is usually a bank of numerous
|
||||
locks).
|
||||
Should be called from a process context (this function might sleep).
|
||||
Returns the address of hwspinlock on success, or NULL on error (e.g.
|
||||
if the hwspinlock is sill in use).
|
||||
|
||||
5. struct hwspinlock
|
||||
5. Important structs
|
||||
|
||||
This struct represents an hwspinlock instance. It is registered by the
|
||||
underlying hwspinlock implementation using the hwspin_lock_register() API.
|
||||
struct hwspinlock_device is a device which usually contains a bank
|
||||
of hardware locks. It is registered by the underlying hwspinlock
|
||||
implementation using the hwspin_lock_register() API.
|
||||
|
||||
/**
|
||||
* struct hwspinlock - vendor-specific hwspinlock implementation
|
||||
*
|
||||
* @dev: underlying device, will be used with runtime PM api
|
||||
* @ops: vendor-specific hwspinlock handlers
|
||||
* @id: a global, unique, system-wide, index of the lock.
|
||||
* @lock: initialized and used by hwspinlock core
|
||||
* @owner: underlying implementation module, used to maintain module ref count
|
||||
* struct hwspinlock_device - a device which usually spans numerous hwspinlocks
|
||||
* @dev: underlying device, will be used to invoke runtime PM api
|
||||
* @ops: platform-specific hwspinlock handlers
|
||||
* @base_id: id index of the first lock in this device
|
||||
* @num_locks: number of locks in this device
|
||||
* @lock: dynamically allocated array of 'struct hwspinlock'
|
||||
*/
|
||||
struct hwspinlock {
|
||||
struct hwspinlock_device {
|
||||
struct device *dev;
|
||||
const struct hwspinlock_ops *ops;
|
||||
int id;
|
||||
spinlock_t lock;
|
||||
struct module *owner;
|
||||
int base_id;
|
||||
int num_locks;
|
||||
struct hwspinlock lock[0];
|
||||
};
|
||||
|
||||
The underlying implementation is responsible to assign the dev, ops, id and
|
||||
owner members. The lock member, OTOH, is initialized and used by the hwspinlock
|
||||
core.
|
||||
struct hwspinlock_device contains an array of hwspinlock structs, each
|
||||
of which represents a single hardware lock:
|
||||
|
||||
/**
|
||||
* struct hwspinlock - this struct represents a single hwspinlock instance
|
||||
* @bank: the hwspinlock_device structure which owns this lock
|
||||
* @lock: initialized and used by hwspinlock core
|
||||
* @priv: private data, owned by the underlying platform-specific hwspinlock drv
|
||||
*/
|
||||
struct hwspinlock {
|
||||
struct hwspinlock_device *bank;
|
||||
spinlock_t lock;
|
||||
void *priv;
|
||||
};
|
||||
|
||||
When registering a bank of locks, the hwspinlock driver only needs to
|
||||
set the priv members of the locks. The rest of the members are set and
|
||||
initialized by the hwspinlock core itself.
|
||||
|
||||
6. Implementation callbacks
|
||||
|
||||
|
||||
Reference in New Issue
Block a user