On 03/12/15 12:38, Lina Iyer wrote::) I was just hacking it to make it easier to understand. Sure.
drivers/hwspinlock/qcom_hwspinlock.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/hwspinlock/qcom_hwspinlock.c b/drivers/hwspinlock/qcom_hwspinlock.c
index 93b62e0..7642524 100644
@@ -25,16 +25,23 @@
-#define QCOM_MUTEX_APPS_PROC_ID 1
-#define QCOM_MUTEX_NUM_LOCKS 32
+#define QCOM_MUTEX_APPS_PROC_ID 1
+#define QCOM_MUTEX_CPUIDLE_OFFSET 128
+#define QCOM_CPUIDLE_LOCK 7
+#define QCOM_MUTEX_NUM_LOCKS 32
static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
struct regmap_field *field = lock->priv;
+ u32 proc_id;
- ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
+ proc_id = hwspin_lock_get_id(lock) == QCOM_CPUIDLE_LOCK ?
+ QCOM_MUTEX_CPUIDLE_OFFSET + smp_processor_id():
So we assume that the caller will always be the CPU that is locking the
lock? Also, do we assume that the remote side knows our CPU scheme here?
smp_processor_id() returns the logical CPU and not the physical CPU
number so hopefully the remote side doesn't care about logical CPU
numbers being written to the lock value.
That would be good, if there is value in that for other platforms, I
Perhaps it would be better to have a way to tell the hwspinlock
framework what value we want written to the lock value.
Good point. I missed it.+ QCOM_MUTEX_APPS_PROC_ID;
+ ret = regmap_field_write(field, proc_id);
@@ -42,7 +49,7 @@ static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
- return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
+ return lock_owner == proc_id;
static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
The unlock path checks proc_id so we need to update the path there too.
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