net: fec: add fec_rx_error_check() to check RX errors

Extract fec_rx_error_check() from fec_enet_rx_queue(), this helper is
used to check RX errors. And it will be used in XDP and XDP zero copy
paths in subsequent patches.

Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260205085742.2685134-3-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: WeiFang-NXP

drivers/net/ethernet/freescale/fec_main.c

@@ -1747,6 +1747,41 @@ static void fec_enet_rx_vlan(const struct net_device *ndev, struct sk_buff *skb)
 	}
 }
 
+static int fec_rx_error_check(struct net_device *ndev, u16 status)
+{
+	if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_NO |
+		      BD_ENET_RX_CR | BD_ENET_RX_OV | BD_ENET_RX_LAST |
+		      BD_ENET_RX_CL)) {
+		ndev->stats.rx_errors++;
+
+		if (status & BD_ENET_RX_OV) {
+			/* FIFO overrun */
+			ndev->stats.rx_fifo_errors++;
+			return -EIO;
+		}
+
+		if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH |
+			      BD_ENET_RX_LAST)) {
+			/* Frame too long or too short. */
+			ndev->stats.rx_length_errors++;
+			if ((status & BD_ENET_RX_LAST) && net_ratelimit())
+				netdev_err(ndev, "rcv is not +last\n");
+		}
+
+		/* CRC Error */
+		if (status & BD_ENET_RX_CR)
+			ndev->stats.rx_crc_errors++;
+
+		/* Report late collisions as a frame error. */
+		if (status & (BD_ENET_RX_NO | BD_ENET_RX_CL))
+			ndev->stats.rx_frame_errors++;
+
+		return -EIO;
+	}
+
+	return 0;
+}
+
 /* During a receive, the bd_rx.cur points to the current incoming buffer.
  * When we update through the ring, if the next incoming buffer has
  * not been given to the system, we just set the empty indicator,
@@ -1807,29 +1842,8 @@ fec_enet_rx_queue(struct net_device *ndev, u16 queue_id, int budget)
 
 		/* Check for errors. */
 		status ^= BD_ENET_RX_LAST;
-		if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_NO |
-			   BD_ENET_RX_CR | BD_ENET_RX_OV | BD_ENET_RX_LAST |
-			   BD_ENET_RX_CL)) {
-			ndev->stats.rx_errors++;
-			if (status & BD_ENET_RX_OV) {
-				/* FIFO overrun */
-				ndev->stats.rx_fifo_errors++;
-				goto rx_processing_done;
-			}
-			if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH
-						| BD_ENET_RX_LAST)) {
-				/* Frame too long or too short. */
-				ndev->stats.rx_length_errors++;
-				if (status & BD_ENET_RX_LAST)
-					netdev_err(ndev, "rcv is not +last\n");
-			}
-			if (status & BD_ENET_RX_CR)	/* CRC Error */
-				ndev->stats.rx_crc_errors++;
-			/* Report late collisions as a frame error. */
-			if (status & (BD_ENET_RX_NO | BD_ENET_RX_CL))
-				ndev->stats.rx_frame_errors++;
+		if (unlikely(fec_rx_error_check(ndev, status)))
 			goto rx_processing_done;
-		}
 
 		/* Process the incoming frame. */
 		ndev->stats.rx_packets++;