[PATCH 3/4] firmware: arm_ffa: Check if receiving notifications are supported before sending

[Sudeep Holla]

Add check to see if the target partition can receive the notifications
before sending any notifications to the partition.

Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
---
 drivers/firmware/arm_ffa/driver.c | 6 +++++-
 include/linux/arm_ffa.h           | 2 ++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 52379885a403..d5087e4f6d35 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -1092,12 +1092,16 @@ static int ffa_notify_request(struct ffa_device *dev, bool is_per_vcpu,
 	return rc;
 }
 
+#define ffa_partition_supports_notify_recv(dev)	\
+	ffa_partition_check_property(dev, FFA_PARTITION_NOTIFICATION_RECV)
+
 static int ffa_notify_send(struct ffa_device *dev, int notify_id,
 			   bool is_per_vcpu, u16 vcpu)
 {
 	u32 flags = 0;
 
-	if (ffa_notifications_disabled())
+	if (ffa_notifications_disabled() ||
+	    !ffa_partition_supports_notify_recv(dev))
 		return -EOPNOTSUPP;
 
 	if (is_per_vcpu)
diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h
index c906f666ff5d..13830be5851d 100644
--- a/include/linux/arm_ffa.h
+++ b/include/linux/arm_ffa.h
@@ -221,6 +221,8 @@ struct ffa_partition_info {
 #define FFA_PARTITION_DIRECT_SEND	BIT(1)
 /* partition can send and receive indirect messages. */
 #define FFA_PARTITION_INDIRECT_MSG	BIT(2)
+/* partition can receive notifications */
+#define FFA_PARTITION_NOTIFICATION_RECV	BIT(3)
 /* partition runs in the AArch64 execution state. */
 #define FFA_PARTITION_AARCH64_EXEC	BIT(8)
 	u32 properties;

-- 
2.43.2