net: mvpp2: cls: Initialize lookup priorities for all entries in the flow

When classifying a packet pertaining to a given flow, the classifier
will issue multiple lookup commands until it finds one with the 'last'
bit set. It expects all prorities to be assign continuously (although
not necessarily in an ordered fashion) from 0 to the number of lookups.

We can initialize this once, and make sure unused lookups are given an
empty port map. This avoids having to maintain priorities and the
information of which lookup is the last.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c

@@ -544,16 +544,27 @@ static void mvpp2_cls_flow_init(struct mvpp2 *priv,
 				const struct mvpp2_cls_flow *flow)
 {
 	struct mvpp2_cls_flow_entry fe;
-	int i;
+	int i, pri = 0;
+
+	/* Assign default values to all entries in the flow */
+	for (i = MVPP2_CLS_FLT_FIRST(flow->flow_id);
+	     i <= MVPP2_CLS_FLT_LAST(flow->flow_id); i++) {
+		memset(&fe, 0, sizeof(fe));
+		fe.index = i;
+		mvpp2_cls_flow_pri_set(&fe, pri++);
 
-	/* C2 lookup */
-	memset(&fe, 0, sizeof(fe));
-	fe.index = MVPP2_CLS_FLT_C2_RSS_ENTRY(flow->flow_id);
+		if (i == MVPP2_CLS_FLT_LAST(flow->flow_id))
+			mvpp2_cls_flow_last_set(&fe, 1);
+
+		mvpp2_cls_flow_write(priv, &fe);
+	}
+
+	/* RSS config C2 lookup */
+	mvpp2_cls_flow_read(priv, MVPP2_CLS_FLT_C2_RSS_ENTRY(flow->flow_id),
+			    &fe);
 
 	mvpp2_cls_flow_eng_set(&fe, MVPP22_CLS_ENGINE_C2);
 	mvpp2_cls_flow_port_id_sel(&fe, true);
-	mvpp2_cls_flow_last_set(&fe, 0);
-	mvpp2_cls_flow_pri_set(&fe, 0);
 	mvpp2_cls_flow_lu_type_set(&fe, MVPP2_CLS_LU_ALL);
 
 	/* Add all ports */
@@ -564,19 +575,19 @@ static void mvpp2_cls_flow_init(struct mvpp2 *priv,
 
 	/* C3Hx lookups */
 	for (i = 0; i < MVPP2_MAX_PORTS; i++) {
-		memset(&fe, 0, sizeof(fe));
-		fe.index = MVPP2_CLS_FLT_HASH_ENTRY(i, flow->flow_id);
+		mvpp2_cls_flow_read(priv,
+				    MVPP2_CLS_FLT_HASH_ENTRY(i, flow->flow_id),
+				    &fe);
 
+		/* Set a default engine. Will be overwritten when setting the
+		 * real HEK parameters
+		 */
+		mvpp2_cls_flow_eng_set(&fe, MVPP22_CLS_ENGINE_C3HA);
 		mvpp2_cls_flow_port_id_sel(&fe, true);
-		mvpp2_cls_flow_pri_set(&fe, i + 1);
 		mvpp2_cls_flow_port_add(&fe, BIT(i));
 
 		mvpp2_cls_flow_write(priv, &fe);
 	}
-
-	/* Update the last entry */
-	mvpp2_cls_flow_last_set(&fe, 1);
-	mvpp2_cls_flow_write(priv, &fe);
 }
 
 /* Adds a field to the Header Extracted Key generation parameters*/