gianfar: Optimize interrupt coalescing configuration

Store the interrupt coalescing values in the form in which they will be
written to the interrupt coalescing registers.  This puts a little overhead
into the ethtool configuration, and takes it out of the interrupt handler
Signed-off-by: Dai Haruki <dai.haruki@freescale.com>
Acked-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/gianfar.c

@@ -428,11 +428,9 @@ static int gfar_probe(struct of_device *ofdev,
 	priv->rx_ring_size = DEFAULT_RX_RING_SIZE;
 
 	priv->txcoalescing = DEFAULT_TX_COALESCE;
-	priv->txcount = DEFAULT_TXCOUNT;
-	priv->txtime = DEFAULT_TXTIME;
+	priv->txic = DEFAULT_TXIC;
 	priv->rxcoalescing = DEFAULT_RX_COALESCE;
-	priv->rxcount = DEFAULT_RXCOUNT;
-	priv->rxtime = DEFAULT_RXTIME;
+	priv->rxic = DEFAULT_RXIC;
 
 	/* Enable most messages by default */
 	priv->msg_enable = (NETIF_MSG_IFUP << 1 ) - 1;
@@ -1060,17 +1058,13 @@ int startup_gfar(struct net_device *dev)
 	phy_start(priv->phydev);
 
 	/* Configure the coalescing support */
-	if (priv->txcoalescing)
-		gfar_write(&regs->txic,
-			   mk_ic_value(priv->txcount, priv->txtime));
-	else
 	gfar_write(&regs->txic, 0);
+	if (priv->txcoalescing)
+		gfar_write(&regs->txic, priv->txic);
 
-	if (priv->rxcoalescing)
-		gfar_write(&regs->rxic,
-			   mk_ic_value(priv->rxcount, priv->rxtime));
-	else
 	gfar_write(&regs->rxic, 0);
+	if (priv->rxcoalescing)
+		gfar_write(&regs->rxic, priv->rxic);
 
 	if (priv->rx_csum_enable)
 		rctrl |= RCTRL_CHECKSUMMING;
@@ -1538,8 +1532,7 @@ static irqreturn_t gfar_transmit(int irq, void *dev_id)
 	/* Otherwise, clear it */
 	if (likely(priv->txcoalescing)) {
 		gfar_write(&priv->regs->txic, 0);
-		gfar_write(&priv->regs->txic,
-			   mk_ic_value(priv->txcount, priv->txtime));
+		gfar_write(&priv->regs->txic, priv->txic);
 	}
 
 	spin_unlock(&priv->txlock);
@@ -1825,8 +1818,7 @@ static int gfar_poll(struct napi_struct *napi, int budget)
 		/* Otherwise, clear it */
 		if (likely(priv->rxcoalescing)) {
 			gfar_write(&priv->regs->rxic, 0);
-			gfar_write(&priv->regs->rxic,
-				   mk_ic_value(priv->rxcount, priv->rxtime));
+			gfar_write(&priv->regs->rxic, priv->rxic);
 		}
 	}
 

drivers/net/gianfar.h

@@ -189,6 +189,12 @@ extern const char gfar_driver_version[];
 #define mk_ic_value(count, time) (IC_ICEN | \
 				mk_ic_icft(count) | \
 				mk_ic_ictt(time))
+#define get_icft_value(ic)	(((unsigned long)ic & IC_ICFT_MASK) >> \
+				 IC_ICFT_SHIFT)
+#define get_ictt_value(ic)	((unsigned long)ic & IC_ICTT_MASK)
+
+#define DEFAULT_TXIC mk_ic_value(DEFAULT_TXCOUNT, DEFAULT_TXTIME)
+#define DEFAULT_RXIC mk_ic_value(DEFAULT_RXCOUNT, DEFAULT_RXTIME)
 
 #define RCTRL_PAL_MASK		0x001f0000
 #define RCTRL_VLEX		0x00002000
@@ -694,8 +700,7 @@ struct gfar_private {
 
 	/* Configuration info for the coalescing features */
 	unsigned char txcoalescing;
-	unsigned short txcount;
-	unsigned short txtime;
+	unsigned long txic;
 
 	/* Buffer descriptor pointers */
 	struct txbd8 *tx_bd_base;	/* First tx buffer descriptor */
@@ -717,8 +722,7 @@ struct gfar_private {
 
 	/* RX Coalescing values */
 	unsigned char rxcoalescing;
-	unsigned short rxcount;
-	unsigned short rxtime;
+	unsigned long rxic;
 
 	struct rxbd8 *rx_bd_base;	/* First Rx buffers */
 	struct rxbd8 *cur_rx;           /* Next free rx ring entry */

drivers/net/gianfar_ethtool.c

@@ -201,8 +201,8 @@ static int gfar_gsettings(struct net_device *dev, struct ethtool_cmd *cmd)
 	if (NULL == phydev)
 		return -ENODEV;
 
-	cmd->maxtxpkt = priv->txcount;
-	cmd->maxrxpkt = priv->rxcount;
+	cmd->maxtxpkt = get_icft_value(priv->txic);
+	cmd->maxrxpkt = get_icft_value(priv->rxic);
 
 	return phy_ethtool_gset(phydev, cmd);
 }
@@ -279,6 +279,10 @@ static unsigned int gfar_ticks2usecs(struct gfar_private *priv, unsigned int tic
 static int gfar_gcoalesce(struct net_device *dev, struct ethtool_coalesce *cvals)
 {
 	struct gfar_private *priv = netdev_priv(dev);
+	unsigned long rxtime;
+	unsigned long rxcount;
+	unsigned long txtime;
+	unsigned long txcount;
 
 	if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_COALESCE))
 		return -EOPNOTSUPP;
@@ -286,11 +290,15 @@ static int gfar_gcoalesce(struct net_device *dev, struct ethtool_coalesce *cvals
 	if (NULL == priv->phydev)
 		return -ENODEV;
 
-	cvals->rx_coalesce_usecs = gfar_ticks2usecs(priv, priv->rxtime);
-	cvals->rx_max_coalesced_frames = priv->rxcount;
+	rxtime  = get_ictt_value(priv->rxic);
+	rxcount = get_icft_value(priv->rxic);
+	txtime  = get_ictt_value(priv->txic);
+	txcount = get_icft_value(priv->txic);;
+	cvals->rx_coalesce_usecs = gfar_ticks2usecs(priv, rxtime);
+	cvals->rx_max_coalesced_frames = rxcount;
 
-	cvals->tx_coalesce_usecs = gfar_ticks2usecs(priv, priv->txtime);
-	cvals->tx_max_coalesced_frames = priv->txcount;
+	cvals->tx_coalesce_usecs = gfar_ticks2usecs(priv, txtime);
+	cvals->tx_max_coalesced_frames = txcount;
 
 	cvals->use_adaptive_rx_coalesce = 0;
 	cvals->use_adaptive_tx_coalesce = 0;
@@ -358,8 +366,9 @@ static int gfar_scoalesce(struct net_device *dev, struct ethtool_coalesce *cvals
 		return -EINVAL;
 	}
 
-	priv->rxtime = gfar_usecs2ticks(priv, cvals->rx_coalesce_usecs);
-	priv->rxcount = cvals->rx_max_coalesced_frames;
+	priv->rxic = mk_ic_value(
+		gfar_usecs2ticks(priv, cvals->rx_coalesce_usecs),
+		cvals->rx_max_coalesced_frames);
 
 	/* Set up tx coalescing */
 	if ((cvals->tx_coalesce_usecs == 0) ||
@@ -381,20 +390,17 @@ static int gfar_scoalesce(struct net_device *dev, struct ethtool_coalesce *cvals
 		return -EINVAL;
 	}
 
-	priv->txtime = gfar_usecs2ticks(priv, cvals->tx_coalesce_usecs);
-	priv->txcount = cvals->tx_max_coalesced_frames;
+	priv->txic = mk_ic_value(
+		gfar_usecs2ticks(priv, cvals->tx_coalesce_usecs),
+		cvals->tx_max_coalesced_frames);
 
-	if (priv->rxcoalescing)
-		gfar_write(&priv->regs->rxic,
-			   mk_ic_value(priv->rxcount, priv->rxtime));
-	else
 	gfar_write(&priv->regs->rxic, 0);
+	if (priv->rxcoalescing)
+		gfar_write(&priv->regs->rxic, priv->rxic);
 
-	if (priv->txcoalescing)
-		gfar_write(&priv->regs->txic,
-			   mk_ic_value(priv->txcount, priv->txtime));
-	else
 	gfar_write(&priv->regs->txic, 0);
+	if (priv->txcoalescing)
+		gfar_write(&priv->regs->txic, priv->txic);
 
 	return 0;
 }