bnxt_en: Fix Priority Bytes and Packets counters in ethtool -S.

There is an indexing bug in determining these ethtool priority
counters.  Instead of using the queue ID to index, we need to
normalize by modulo 10 to get the index.  This index is then used
to obtain the proper CoS queue counter.  Rename bp->pri2cos to
bp->pri2cos_idx to make this more clear.

Fixes: e37fed7 ("bnxt_en: Add ethtool -S priority counters.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -7406,14 +7406,22 @@ static int bnxt_hwrm_port_qstats_ext(struct bnxt *bp)
 		pri2cos = &resp2->pri0_cos_queue_id;
 		for (i = 0; i < 8; i++) {
 			u8 queue_id = pri2cos[i];
+			u8 queue_idx;
 
+			/* Per port queue IDs start from 0, 10, 20, etc */
+			queue_idx = queue_id % 10;
+			if (queue_idx > BNXT_MAX_QUEUE) {
+				bp->pri2cos_valid = false;
+				goto qstats_done;
+			}
 			for (j = 0; j < bp->max_q; j++) {
 				if (bp->q_ids[j] == queue_id)
-					bp->pri2cos[i] = j;
+					bp->pri2cos_idx[i] = queue_idx;
 			}
 		}
 		bp->pri2cos_valid = 1;
 	}
+qstats_done:
 	mutex_unlock(&bp->hwrm_cmd_lock);
 	return rc;
 }

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1716,7 +1716,7 @@ struct bnxt {
 	u16			fw_rx_stats_ext_size;
 	u16			fw_tx_stats_ext_size;
 	u16			hw_ring_stats_size;
-	u8			pri2cos[8];
+	u8			pri2cos_idx[8];
 	u8			pri2cos_valid;
 
 	u16			hwrm_max_req_len;

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -589,25 +589,25 @@ static void bnxt_get_ethtool_stats(struct net_device *dev,
 		if (bp->pri2cos_valid) {
 			for (i = 0; i < 8; i++, j++) {
 				long n = bnxt_rx_bytes_pri_arr[i].base_off +
-					 bp->pri2cos[i];
+					 bp->pri2cos_idx[i];
 
 				buf[j] = le64_to_cpu(*(rx_port_stats_ext + n));
 			}
 			for (i = 0; i < 8; i++, j++) {
 				long n = bnxt_rx_pkts_pri_arr[i].base_off +
-					 bp->pri2cos[i];
+					 bp->pri2cos_idx[i];
 
 				buf[j] = le64_to_cpu(*(rx_port_stats_ext + n));
 			}
 			for (i = 0; i < 8; i++, j++) {
 				long n = bnxt_tx_bytes_pri_arr[i].base_off +
-					 bp->pri2cos[i];
+					 bp->pri2cos_idx[i];
 
 				buf[j] = le64_to_cpu(*(tx_port_stats_ext + n));
 			}
 			for (i = 0; i < 8; i++, j++) {
 				long n = bnxt_tx_pkts_pri_arr[i].base_off +
-					 bp->pri2cos[i];
+					 bp->pri2cos_idx[i];
 
 				buf[j] = le64_to_cpu(*(tx_port_stats_ext + n));
 			}