ti: k3: drivers: ti_sci: Retry message receive on bad sequence ID

When we get a sequence ID that does not match what we expect then the we
are looking at is not the one we are expecting and so we error out. We
can also assume this message is a stale message left in the queue, in
this case we can read in the next message and check again for our
message. Switch to doing that here. We only retry a set number of times
so we don't lock the system if our message is actually lost and will
never show up.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Change-Id: I6c8186ccc45e646d3ba9d431f7d4c451dcd70c5c
diff --git a/plat/ti/k3/common/drivers/ti_sci/ti_sci.c b/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
index a376e6e..ac33278 100644
--- a/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
+++ b/plat/ti/k3/common/drivers/ti_sci/ti_sci.c
@@ -116,21 +116,28 @@
 {
 	struct k3_sec_proxy_msg *msg = &xfer->rx_message;
 	struct ti_sci_msg_hdr *hdr;
+	unsigned int retry = 5;
 	int ret;
 
-	/* Receive the response */
-	ret = k3_sec_proxy_recv(chan, msg);
-	if (ret) {
-		ERROR("Message receive failed (%d)\n", ret);
-		return ret;
-	}
+	for (; retry > 0; retry--) {
+		/* Receive the response */
+		ret = k3_sec_proxy_recv(chan, msg);
+		if (ret) {
+			ERROR("Message receive failed (%d)\n", ret);
+			return ret;
+		}
 
-	/* msg is updated by Secure Proxy driver */
-	hdr = (struct ti_sci_msg_hdr *)msg->buf;
+		/* msg is updated by Secure Proxy driver */
+		hdr = (struct ti_sci_msg_hdr *)msg->buf;
 
-	/* Sanity check for message response */
-	if (hdr->seq != info.seq) {
-		ERROR("Message for %d is not expected\n", hdr->seq);
+		/* Sanity check for message response */
+		if (hdr->seq == info.seq)
+			break;
+		else
+			WARN("Message with sequence ID %u is not expected\n", hdr->seq);
+	}
+	if (!retry) {
+		ERROR("Timed out waiting for message\n");
 		return -EINVAL;
 	}