net/wan/fsl_ucc_hdlc: error counters

Extract error information from rx and tx buffer descriptors,
and update error counters.

Signed-off-by: Mathias Thore <mathias.thore@infinera.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wan/fsl_ucc_hdlc.c

@@ -36,6 +36,7 @@
 #define DRV_NAME "ucc_hdlc"
 
 #define TDM_PPPOHT_SLIC_MAXIN
+#define RX_BD_ERRORS (R_CD_S | R_OV_S | R_CR_S | R_AB_S | R_NO_S | R_LG_S)
 
 static struct ucc_tdm_info utdm_primary_info = {
 	.uf_info = {
@@ -430,12 +431,25 @@ static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
+static int hdlc_tx_restart(struct ucc_hdlc_private *priv)
+{
+	u32 cecr_subblock;
+
+	cecr_subblock =
+		ucc_fast_get_qe_cr_subblock(priv->ut_info->uf_info.ucc_num);
+
+	qe_issue_cmd(QE_RESTART_TX, cecr_subblock,
+		     QE_CR_PROTOCOL_UNSPECIFIED, 0);
+	return 0;
+}
+
 static int hdlc_tx_done(struct ucc_hdlc_private *priv)
 {
 	/* Start from the next BD that should be filled */
 	struct net_device *dev = priv->ndev;
 	struct qe_bd *bd;		/* BD pointer */
 	u16 bd_status;
+	int tx_restart = 0;
 
 	bd = priv->dirty_tx;
 	bd_status = ioread16be(&bd->status);
@@ -444,6 +458,15 @@ static int hdlc_tx_done(struct ucc_hdlc_private *priv)
 	while ((bd_status & T_R_S) == 0) {
 		struct sk_buff *skb;
 
+		if (bd_status & T_UN_S) { /* Underrun */
+			dev->stats.tx_fifo_errors++;
+			tx_restart = 1;
+		}
+		if (bd_status & T_CT_S) { /* Carrier lost */
+			dev->stats.tx_carrier_errors++;
+			tx_restart = 1;
+		}
+
 		/* BD contains already transmitted buffer.   */
 		/* Handle the transmitted buffer and release */
 		/* the BD to be used with the current frame  */
@@ -475,6 +498,9 @@ static int hdlc_tx_done(struct ucc_hdlc_private *priv)
 	}
 	priv->dirty_tx = bd;
 
+	if (tx_restart)
+		hdlc_tx_restart(priv);
+
 	return 0;
 }
 
@@ -493,11 +519,22 @@ static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
 
 	/* while there are received buffers and BD is full (~R_E) */
 	while (!((bd_status & (R_E_S)) || (--rx_work_limit < 0))) {
-		if (bd_status & R_OV_S)
-			dev->stats.rx_over_errors++;
-		if (bd_status & R_CR_S) {
-			dev->stats.rx_crc_errors++;
-			dev->stats.rx_dropped++;
+		if (bd_status & (RX_BD_ERRORS)) {
+			dev->stats.rx_errors++;
+
+			if (bd_status & R_CD_S)
+				dev->stats.collisions++;
+			if (bd_status & R_OV_S)
+				dev->stats.rx_fifo_errors++;
+			if (bd_status & R_CR_S)
+				dev->stats.rx_crc_errors++;
+			if (bd_status & R_AB_S)
+				dev->stats.rx_over_errors++;
+			if (bd_status & R_NO_S)
+				dev->stats.rx_frame_errors++;
+			if (bd_status & R_LG_S)
+				dev->stats.rx_length_errors++;
+
 			goto recycle;
 		}
 		bdbuffer = priv->rx_buffer +
@@ -546,7 +583,7 @@ static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
 		netif_receive_skb(skb);
 
 recycle:
-		iowrite16be(bd_status | R_E_S | R_I_S, &bd->status);
+		iowrite16be((bd_status & R_W_S) | R_E_S | R_I_S, &bd->status);
 
 		/* update to point at the next bd */
 		if (bd_status & R_W_S) {
@@ -622,7 +659,7 @@ static irqreturn_t ucc_hdlc_irq_handler(int irq, void *dev_id)
 
 	/* Errors and other events */
 	if (ucce >> 16 & UCC_HDLC_UCCE_BSY)
-		dev->stats.rx_errors++;
+		dev->stats.rx_missed_errors++;
 	if (ucce >> 16 & UCC_HDLC_UCCE_TXE)
 		dev->stats.tx_errors++;