4 files changed, 35 insertions, 20 deletions
diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 4d231bc375e0..b14cbdae94e8 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -481,11 +481,16 @@ static int ffa_msg_send_direct_req2(u16 src_id, u16 dst_id, const uuid_t *uuid,
 				    struct ffa_send_direct_data2 *data)
 {
 	u32 src_dst_ids = PACK_TARGET_INFO(src_id, dst_id);
+	union {
+		uuid_t uuid;
+		__le64 regs[2];
+	} uuid_regs = { .uuid = *uuid };
 	ffa_value_t ret, args = {
-		.a0 = FFA_MSG_SEND_DIRECT_REQ2, .a1 = src_dst_ids,
+		.a0 = FFA_MSG_SEND_DIRECT_REQ2,
+		.a1 = src_dst_ids,
+		.a2 = le64_to_cpu(uuid_regs.regs[0]),
+		.a3 = le64_to_cpu(uuid_regs.regs[1]),
 	};
-
-	export_uuid((u8 *)&args.a2, uuid);
 	memcpy((void *)&args + offsetof(ffa_value_t, a4), data, sizeof(*data));
 
 	invoke_ffa_fn(args, &ret);
@@ -496,7 +501,7 @@ static int ffa_msg_send_direct_req2(u16 src_id, u16 dst_id, const uuid_t *uuid,
 		return ffa_to_linux_errno((int)ret.a2);
 
 	if (ret.a0 == FFA_MSG_SEND_DIRECT_RESP2) {
-		memcpy(data, &ret.a4, sizeof(*data));
+		memcpy(data, (void *)&ret + offsetof(ffa_value_t, a4), sizeof(*data));
 		return 0;
 	}
 
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 88c5c4ff4bb6..a477b5ade38d 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -2976,10 +2976,8 @@ static struct scmi_debug_info *scmi_debugfs_common_setup(struct scmi_info *info)
 	dbg->top_dentry = top_dentry;
 
 	if (devm_add_action_or_reset(info->dev,
-				     scmi_debugfs_common_cleanup, dbg)) {
-		scmi_debugfs_common_cleanup(dbg);
+				     scmi_debugfs_common_cleanup, dbg))
 		return NULL;
-	}
 
 	return dbg;
 }
diff --git a/drivers/firmware/arm_scmi/transports/Makefile b/drivers/firmware/arm_scmi/transports/Makefile
index 362a406f08e6..3ba3d3bee151 100644
--- a/drivers/firmware/arm_scmi/transports/Makefile
+++ b/drivers/firmware/arm_scmi/transports/Makefile
@@ -1,8 +1,10 @@
 # SPDX-License-Identifier: GPL-2.0-only
-scmi_transport_mailbox-objs := mailbox.o
-obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
+# Keep before scmi_transport_mailbox.o to allow precedence
+# while matching the compatible.
 scmi_transport_smc-objs := smc.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o
+scmi_transport_mailbox-objs := mailbox.o
+obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
 scmi_transport_optee-objs := optee.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += scmi_transport_optee.o
 scmi_transport_virtio-objs := virtio.o
diff --git a/drivers/firmware/arm_scmi/transports/mailbox.c b/drivers/firmware/arm_scmi/transports/mailbox.c
index 1a754dee24f7..e3d5f7560990 100644
--- a/drivers/firmware/arm_scmi/transports/mailbox.c
+++ b/drivers/firmware/arm_scmi/transports/mailbox.c
@@ -25,6 +25,7 @@
  * @chan_platform_receiver: Optional Platform Receiver mailbox unidirectional channel
  * @cinfo: SCMI channel info
  * @shmem: Transmit/Receive shared memory area
+ * @chan_lock: Lock that prevents multiple xfers from being queued
  */
 struct scmi_mailbox {
 	struct mbox_client cl;
@@ -33,6 +34,7 @@ struct scmi_mailbox {
 	struct mbox_chan *chan_platform_receiver;
 	struct scmi_chan_info *cinfo;
 	struct scmi_shared_mem __iomem *shmem;
+	struct mutex chan_lock;
 };
 
 #define client_to_scmi_mailbox(c) container_of(c, struct scmi_mailbox, cl)
@@ -238,6 +240,7 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 
 	cinfo->transport_info = smbox;
 	smbox->cinfo = cinfo;
+	mutex_init(&smbox->chan_lock);
 
 	return 0;
 }
@@ -267,13 +270,23 @@ static int mailbox_send_message(struct scmi_chan_info *cinfo,
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 	int ret;
 
-	ret = mbox_send_message(smbox->chan, xfer);
+	/*
+	 * The mailbox layer has its own queue. However the mailbox queue
+	 * confuses the per message SCMI timeouts since the clock starts when
+	 * the message is submitted into the mailbox queue. So when multiple
+	 * messages are queued up the clock starts on all messages instead of
+	 * only the one inflight.
+	 */
+	mutex_lock(&smbox->chan_lock);
 
-	/* mbox_send_message returns non-negative value on success, so reset */
-	if (ret > 0)
-		ret = 0;
+	ret = mbox_send_message(smbox->chan, xfer);
+	/* mbox_send_message returns non-negative value on success */
+	if (ret < 0) {
+		mutex_unlock(&smbox->chan_lock);
+		return ret;
+	}
 
-	return ret;
+	return 0;
 }
 
 static void mailbox_mark_txdone(struct scmi_chan_info *cinfo, int ret,
@@ -281,13 +294,10 @@ static void mailbox_mark_txdone(struct scmi_chan_info *cinfo, int ret,
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	/*
-	 * NOTE: we might prefer not to need the mailbox ticker to manage the
-	 * transfer queueing since the protocol layer queues things by itself.
-	 * Unfortunately, we have to kick the mailbox framework after we have
-	 * received our message.
-	 */
 	mbox_client_txdone(smbox->chan, ret);
+
+	/* Release channel */
+	mutex_unlock(&smbox->chan_lock);
 }
 
 static void mailbox_fetch_response(struct scmi_chan_info *cinfo,