[PATCH 4/7] hwspinlock: qcom: implement bust operation

Chris Lew
2024-05-16T22:59:46Z

From: Richard Maina <quic_rmaina@quicinc.com>

Implement a new operation qcom_hwspinlock_bust() which can be invoked
to free any locks that are in use when a remoteproc is stopped or
crashed.

Signed-off-by: Richard Maina <quic_rmaina@quicinc.com>
Signed-off-by: Chris Lew <quic_clew@quicinc.com>
---
drivers/hwspinlock/qcom_hwspinlock.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/hwspinlock/qcom_hwspinlock.c b/drivers/hwspinlock/qcom_hwspinlock.c
index 814dfe8697bf..0390979fd765 100644
--- a/drivers/hwspinlock/qcom_hwspinlock.c
+++ b/drivers/hwspinlock/qcom_hwspinlock.c
@@ -64,9 +64,34 @@ static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
pr_err("%s: failed to unlock spinlock\n", __func__);
}

+static int qcom_hwspinlock_bust(struct hwspinlock *lock, unsigned int id)
+{
+ struct regmap_field *field = lock->priv;
+ u32 owner;
+ int ret;
+
+ ret = regmap_field_read(field, &owner);
+ if (ret) {
+ dev_err(lock->bank->dev, "unable to query spinlock owner\n");
+ return ret;
+ }
+
+ if (owner != id)
+ return 0;
+
+ ret = regmap_field_write(field, 0);
+ if (ret) {
+ dev_err(lock->bank->dev, "failed to bust spinlock\n");
+ return ret;
+ }
+
+ return 0;
+}
+
static const struct hwspinlock_ops qcom_hwspinlock_ops = {
.trylock = qcom_hwspinlock_trylock,
.unlock = qcom_hwspinlock_unlock,
+ .bust = qcom_hwspinlock_bust,
};

static const struct regmap_config sfpb_mutex_config = {

--
2.25.1