net: sgi: ioc3-eth: introduce chip start function

ioc3_init did everything from reset to init rings to starting the chip.
This change move out chip start into a new function as preparation
for easier handling of receive buffer allocation failures.
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sgi/ioc3-eth.c

@@ -105,6 +105,7 @@ static void ioc3_set_multicast_list(struct net_device *dev);
 static netdev_tx_t ioc3_start_xmit(struct sk_buff *skb, struct net_device *dev);
 static void ioc3_timeout(struct net_device *dev);
 static inline unsigned int ioc3_hash(const unsigned char *addr);
+static void ioc3_start(struct ioc3_private *ip);
 static inline void ioc3_stop(struct ioc3_private *ip);
 static void ioc3_init(struct net_device *dev);
 
@@ -660,6 +661,7 @@ static void ioc3_error(struct net_device *dev, u32 eisr)
 
 	ioc3_stop(ip);
 	ioc3_init(dev);
+	ioc3_start(ip);
 	ioc3_mii_init(ip);
 
 	netif_wake_queue(dev);
@@ -827,31 +829,11 @@ static void ioc3_alloc_rx_bufs(struct net_device *dev)
 static void ioc3_init_rings(struct net_device *dev)
 {
 	struct ioc3_private *ip = netdev_priv(dev);
-	struct ioc3_ethregs *regs = ip->regs;
-	unsigned long ring;
 
 	ioc3_free_rx_bufs(ip);
 	ioc3_alloc_rx_bufs(dev);
 
 	ioc3_clean_tx_ring(ip);
-
-	/* Now the rx ring base, consume & produce registers.  */
-	ring = ioc3_map(ip->rxr, 0);
-	writel(ring >> 32, &regs->erbr_h);
-	writel(ring & 0xffffffff, &regs->erbr_l);
-	writel(ip->rx_ci << 3, &regs->ercir);
-	writel((ip->rx_pi << 3) | ERPIR_ARM, &regs->erpir);
-
-	ring = ioc3_map(ip->txr, 0);
-
-	ip->txqlen = 0;					/* nothing queued  */
-
-	/* Now the tx ring base, consume & produce registers.  */
-	writel(ring >> 32, &regs->etbr_h);
-	writel(ring & 0xffffffff, &regs->etbr_l);
-	writel(ip->tx_pi << 7, &regs->etpir);
-	writel(ip->tx_ci << 7, &regs->etcir);
-	readl(&regs->etcir);				/* Flush */
 }
 
 static inline void ioc3_ssram_disc(struct ioc3_private *ip)
@@ -908,6 +890,30 @@ static void ioc3_init(struct net_device *dev)
 	writel(42, &regs->ersr);		/* XXX should be random */
 
 	ioc3_init_rings(dev);
+}
+
+static void ioc3_start(struct ioc3_private *ip)
+{
+	struct ioc3_ethregs *regs = ip->regs;
+	unsigned long ring;
+
+	/* Now the rx ring base, consume & produce registers.  */
+	ring = ioc3_map(ip->rxr, 0);
+	writel(ring >> 32, &regs->erbr_h);
+	writel(ring & 0xffffffff, &regs->erbr_l);
+	writel(ip->rx_ci << 3, &regs->ercir);
+	writel((ip->rx_pi << 3) | ERPIR_ARM, &regs->erpir);
+
+	ring = ioc3_map(ip->txr, 0);
+
+	ip->txqlen = 0;					/* nothing queued  */
+
+	/* Now the tx ring base, consume & produce registers.  */
+	writel(ring >> 32, &regs->etbr_h);
+	writel(ring & 0xffffffff, &regs->etbr_l);
+	writel(ip->tx_pi << 7, &regs->etpir);
+	writel(ip->tx_ci << 7, &regs->etcir);
+	readl(&regs->etcir);				/* Flush */
 
 	ip->emcr |= ((RX_OFFSET / 2) << EMCR_RXOFF_SHIFT) | EMCR_TXDMAEN |
 		    EMCR_TXEN | EMCR_RXDMAEN | EMCR_RXEN | EMCR_PADEN;
@@ -940,6 +946,7 @@ static int ioc3_open(struct net_device *dev)
 	ip->ehar_h = 0;
 	ip->ehar_l = 0;
 	ioc3_init(dev);
+	ioc3_start(ip);
 	ioc3_mii_start(ip);
 
 	netif_start_queue(dev);
@@ -1208,6 +1215,7 @@ static int ioc3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	}
 
 	ioc3_init(dev);
+	ioc3_start(ip);
 
 	ip->pdev = pdev;
 
@@ -1430,6 +1438,7 @@ static void ioc3_timeout(struct net_device *dev)
 
 	ioc3_stop(ip);
 	ioc3_init(dev);
+	ioc3_start(ip);
 	ioc3_mii_init(ip);
 	ioc3_mii_start(ip);