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-rw-r--r--Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt25
-rw-r--r--Documentation/hwspinlock.txt81
2 files changed, 101 insertions, 5 deletions
diff --git a/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt
index 2c9804f4f4ac..8d365f89694c 100644
--- a/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt
+++ b/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt
@@ -1,12 +1,16 @@
-OMAP4+ HwSpinlock Driver
-========================
+TI HwSpinlock for OMAP and K3 based SoCs
+=========================================
Required properties:
-- compatible: Should be "ti,omap4-hwspinlock" for
- OMAP44xx, OMAP54xx, AM33xx, AM43xx, DRA7xx SoCs
+- compatible: Should be one of the following,
+ "ti,omap4-hwspinlock" for
+ OMAP44xx, OMAP54xx, AM33xx, AM43xx, DRA7xx SoCs
+ "ti,am654-hwspinlock" for
+ K3 AM65x and J721E SoCs
- reg: Contains the hwspinlock module register address space
(base address and length)
- ti,hwmods: Name of the hwmod associated with the hwspinlock device
+ (for OMAP architecture based SoCs only)
- #hwlock-cells: Should be 1. The OMAP hwspinlock users will use a
0-indexed relative hwlock number as the argument
specifier value for requesting a specific hwspinlock
@@ -17,10 +21,21 @@ Please look at the generic hwlock binding for usage information for consumers,
Example:
-/* OMAP4 */
+1. OMAP4 SoCs
hwspinlock: spinlock@4a0f6000 {
compatible = "ti,omap4-hwspinlock";
reg = <0x4a0f6000 0x1000>;
ti,hwmods = "spinlock";
#hwlock-cells = <1>;
};
+
+2. AM65x SoCs and J721E SoCs
+&cbass_main {
+ cbass_main_navss: interconnect0 {
+ hwspinlock: spinlock@30e00000 {
+ compatible = "ti,am654-hwspinlock";
+ reg = <0x00 0x30e00000 0x00 0x1000>;
+ #hwlock-cells = <1>;
+ };
+ };
+};
diff --git a/Documentation/hwspinlock.txt b/Documentation/hwspinlock.txt
index ed640a278185..6f03713b7003 100644
--- a/Documentation/hwspinlock.txt
+++ b/Documentation/hwspinlock.txt
@@ -136,6 +136,39 @@ The function will never sleep.
::
+ int hwspin_lock_timeout_raw(struct hwspinlock *hwlock, unsigned int timeout);
+
+Lock a previously-assigned hwspinlock with a timeout limit (specified in
+msecs). If the hwspinlock is already taken, the function will busy loop
+waiting for it to be released, but give up when the timeout elapses.
+
+Caution: User must protect the routine of getting hardware lock with mutex
+or spinlock to avoid dead-lock, that will let user can do some time-consuming
+or sleepable operations under the hardware lock.
+
+Returns 0 when successful and an appropriate error code otherwise (most
+notably -ETIMEDOUT if the hwspinlock is still busy after timeout msecs).
+
+The function will never sleep.
+
+::
+
+ int hwspin_lock_timeout_in_atomic(struct hwspinlock *hwlock, unsigned int to);
+
+Lock a previously-assigned hwspinlock with a timeout limit (specified in
+msecs). If the hwspinlock is already taken, the function will busy loop
+waiting for it to be released, but give up when the timeout elapses.
+
+This function shall be called only from an atomic context and the timeout
+value shall not exceed a few msecs.
+
+Returns 0 when successful and an appropriate error code otherwise (most
+notably -ETIMEDOUT if the hwspinlock is still busy after timeout msecs).
+
+The function will never sleep.
+
+::
+
int hwspin_trylock(struct hwspinlock *hwlock);
@@ -186,6 +219,34 @@ The function will never sleep.
::
+ int hwspin_trylock_raw(struct hwspinlock *hwlock);
+
+Attempt to lock a previously-assigned hwspinlock, but immediately fail if
+it is already taken.
+
+Caution: User must protect the routine of getting hardware lock with mutex
+or spinlock to avoid dead-lock, that will let user can do some time-consuming
+or sleepable operations under the hardware lock.
+
+Returns 0 on success and an appropriate error code otherwise (most
+notably -EBUSY if the hwspinlock was already taken).
+The function will never sleep.
+
+::
+
+ int hwspin_trylock_in_atomic(struct hwspinlock *hwlock);
+
+Attempt to lock a previously-assigned hwspinlock, but immediately fail if
+it is already taken.
+
+This function shall be called only from an atomic context.
+
+Returns 0 on success and an appropriate error code otherwise (most
+notably -EBUSY if the hwspinlock was already taken).
+The function will never sleep.
+
+::
+
void hwspin_unlock(struct hwspinlock *hwlock);
Unlock a previously-locked hwspinlock. Always succeed, and can be called
@@ -222,6 +283,26 @@ the given flags. This function will never sleep.
::
+ void hwspin_unlock_raw(struct hwspinlock *hwlock);
+
+Unlock a previously-locked hwspinlock.
+
+The caller should **never** unlock an hwspinlock which is already unlocked.
+Doing so is considered a bug (there is no protection against this).
+This function will never sleep.
+
+::
+
+ void hwspin_unlock_in_atomic(struct hwspinlock *hwlock);
+
+Unlock a previously-locked hwspinlock.
+
+The caller should **never** unlock an hwspinlock which is already unlocked.
+Doing so is considered a bug (there is no protection against this).
+This function will never sleep.
+
+::
+
int hwspin_lock_get_id(struct hwspinlock *hwlock);
Retrieve id number of a given hwspinlock. This is needed when an