1 files changed, 131 insertions, 90 deletions

diff --git a/drivers/net/greth.c b/drivers/net/greth.c
index 27d6960ce09e..fdb0333f5cb6 100644
--- a/drivers/net/greth.c
+++ b/drivers/net/greth.c
@@ -1,7 +1,7 @@
 /*
  * Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
  *
- * 2005-2009 (c) Aeroflex Gaisler AB
+ * 2005-2010 (c) Aeroflex Gaisler AB
  *
  * This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
  * available in the GRLIB VHDL IP core library.
@@ -356,6 +356,8 @@ static int greth_open(struct net_device *dev)
                 dev_dbg(&dev->dev, " starting queue\n");
         netif_start_queue(dev);
 
+        GRETH_REGSAVE(greth->regs->status, 0xFF);
+
         napi_enable(&greth->napi);
 
         greth_enable_irqs(greth);
@@ -371,7 +373,9 @@ static int greth_close(struct net_device *dev)
 
         napi_disable(&greth->napi);
 
+        greth_disable_irqs(greth);
         greth_disable_tx(greth);
+        greth_disable_rx(greth);
 
         netif_stop_queue(dev);
 
@@ -388,12 +392,20 @@ greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
         struct greth_private *greth = netdev_priv(dev);
         struct greth_bd *bdp;
         int err = NETDEV_TX_OK;
-        u32 status, dma_addr;
+        u32 status, dma_addr, ctrl;
+        unsigned long flags;
 
-        bdp = greth->tx_bd_base + greth->tx_next;
+        /* Clean TX Ring */
+        greth_clean_tx(greth->netdev);
 
         if (unlikely(greth->tx_free <= 0)) {
+                spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
+                ctrl = GRETH_REGLOAD(greth->regs->control);
+                /* Enable TX IRQ only if not already in poll() routine */
+                if (ctrl & GRETH_RXI)
+                        GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
                 netif_stop_queue(dev);
+                spin_unlock_irqrestore(&greth->devlock, flags);
                 return NETDEV_TX_BUSY;
         }
 
@@ -406,13 +418,14 @@ greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 goto out;
         }
 
+        bdp = greth->tx_bd_base + greth->tx_next;
         dma_addr = greth_read_bd(&bdp->addr);
 
         memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
 
         dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
 
-        status = GRETH_BD_EN | (skb->len & GRETH_BD_LEN);
+        status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
 
         /* Wrap around descriptor ring */
         if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
@@ -422,22 +435,11 @@ greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
         greth->tx_next = NEXT_TX(greth->tx_next);
         greth->tx_free--;
 
-        /* No more descriptors */
-        if (unlikely(greth->tx_free == 0)) {
-
-                /* Free transmitted descriptors */
-                greth_clean_tx(dev);
-
-                /* If nothing was cleaned, stop queue & wait for irq */
-                if (unlikely(greth->tx_free == 0)) {
-                        status |= GRETH_BD_IE;
-                        netif_stop_queue(dev);
-                }
-        }
-
         /* Write descriptor control word and enable transmission */
         greth_write_bd(&bdp->stat, status);
+        spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
         greth_enable_tx(greth);
+        spin_unlock_irqrestore(&greth->devlock, flags);
 
 out:
         dev_kfree_skb(skb);
@@ -450,13 +452,23 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
 {
         struct greth_private *greth = netdev_priv(dev);
         struct greth_bd *bdp;
-        u32 status = 0, dma_addr;
+        u32 status = 0, dma_addr, ctrl;
         int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
+        unsigned long flags;
 
         nr_frags = skb_shinfo(skb)->nr_frags;
 
+        /* Clean TX Ring */
+        greth_clean_tx_gbit(dev);
+
         if (greth->tx_free < nr_frags + 1) {
+                spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
+                ctrl = GRETH_REGLOAD(greth->regs->control);
+                /* Enable TX IRQ only if not already in poll() routine */
+                if (ctrl & GRETH_RXI)
+                        GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
                 netif_stop_queue(dev);
+                spin_unlock_irqrestore(&greth->devlock, flags);
                 err = NETDEV_TX_BUSY;
                 goto out;
         }
@@ -499,7 +511,7 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
                 greth->tx_skbuff[curr_tx] = NULL;
                 bdp = greth->tx_bd_base + curr_tx;
 
-                status = GRETH_TXBD_CSALL;
+                status = GRETH_TXBD_CSALL | GRETH_BD_EN;
                 status |= frag->size & GRETH_BD_LEN;
 
                 /* Wrap around descriptor ring */
@@ -509,14 +521,8 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
                 /* More fragments left */
                 if (i < nr_frags - 1)
                         status |= GRETH_TXBD_MORE;
-
-                /* ... last fragment, check if out of descriptors  */
-                else if (greth->tx_free - nr_frags - 1 < (MAX_SKB_FRAGS + 1)) {
-
-                        /* Enable interrupts and stop queue */
-                        status |= GRETH_BD_IE;
-                        netif_stop_queue(dev);
-                }
+                else
+                        status |= GRETH_BD_IE; /* enable IRQ on last fragment */
 
                 greth_write_bd(&bdp->stat, status);
 
@@ -536,26 +542,29 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
 
         wmb();
 
-        /* Enable the descriptors that we configured ...  */
-        for (i = 0; i < nr_frags + 1; i++) {
-                bdp = greth->tx_bd_base + greth->tx_next;
-                greth_write_bd(&bdp->stat, greth_read_bd(&bdp->stat) | GRETH_BD_EN);
-                greth->tx_next = NEXT_TX(greth->tx_next);
-                greth->tx_free--;
-        }
+        /* Enable the descriptor chain by enabling the first descriptor */
+        bdp = greth->tx_bd_base + greth->tx_next;
+        greth_write_bd(&bdp->stat, greth_read_bd(&bdp->stat) | GRETH_BD_EN);
+        greth->tx_next = curr_tx;
+        greth->tx_free -= nr_frags + 1;
 
+        wmb();
+
+        spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
         greth_enable_tx(greth);
+        spin_unlock_irqrestore(&greth->devlock, flags);
 
         return NETDEV_TX_OK;
 
 frag_map_error:
-        /* Unmap SKB mappings that succeeded */
+        /* Unmap SKB mappings that succeeded and disable descriptor */
         for (i = 0; greth->tx_next + i != curr_tx; i++) {
                 bdp = greth->tx_bd_base + greth->tx_next + i;
                 dma_unmap_single(greth->dev,
                                  greth_read_bd(&bdp->addr),
                                  greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
                                  DMA_TO_DEVICE);
+                greth_write_bd(&bdp->stat, 0);
         }
 map_error:
         if (net_ratelimit())
@@ -565,12 +574,11 @@ out:
         return err;
 }
 
-
 static irqreturn_t greth_interrupt(int irq, void *dev_id)
 {
         struct net_device *dev = dev_id;
         struct greth_private *greth;
-        u32 status;
+        u32 status, ctrl;
         irqreturn_t retval = IRQ_NONE;
 
         greth = netdev_priv(dev);
@@ -580,13 +588,15 @@ static irqreturn_t greth_interrupt(int irq, void *dev_id)
         /* Get the interrupt events that caused us to be here. */
         status = GRETH_REGLOAD(greth->regs->status);
 
-        /* Handle rx and tx interrupts through poll */
-        if (status & (GRETH_INT_RX | GRETH_INT_TX)) {
-
-                /* Clear interrupt status */
-                GRETH_REGORIN(greth->regs->status,
-                              status & (GRETH_INT_RX | GRETH_INT_TX));
+        /* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
+         * set regardless of whether IRQ is enabled or not. Especially
+         * important when shared IRQ.
+         */
+        ctrl = GRETH_REGLOAD(greth->regs->control);
 
+        /* Handle rx and tx interrupts through poll */
+        if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
+            ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
                 retval = IRQ_HANDLED;
 
                 /* Disable interrupts and schedule poll() */
@@ -610,6 +620,8 @@ static void greth_clean_tx(struct net_device *dev)
 
         while (1) {
                 bdp = greth->tx_bd_base + greth->tx_last;
+                GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
+                mb();
                 stat = greth_read_bd(&bdp->stat);
 
                 if (unlikely(stat & GRETH_BD_EN))
@@ -670,7 +682,10 @@ static void greth_clean_tx_gbit(struct net_device *dev)
 
                 /* We only clean fully completed SKBs */
                 bdp_last_frag = greth->tx_bd_base + SKIP_TX(greth->tx_last, nr_frags);
-                stat = bdp_last_frag->stat;
+
+                GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
+                mb();
+                stat = greth_read_bd(&bdp_last_frag->stat);
 
                 if (stat & GRETH_BD_EN)
                         break;
@@ -702,21 +717,9 @@ static void greth_clean_tx_gbit(struct net_device *dev)
                 greth->tx_free += nr_frags+1;
                 dev_kfree_skb(skb);
         }
-        if (greth->tx_free > (MAX_SKB_FRAGS + 1)) {
-                netif_wake_queue(dev);
-        }
-}
 
-static int greth_pending_packets(struct greth_private *greth)
-{
-        struct greth_bd *bdp;
-        u32 status;
-        bdp = greth->rx_bd_base + greth->rx_cur;
-        status = greth_read_bd(&bdp->stat);
-        if (status & GRETH_BD_EN)
-                return 0;
-        else
-                return 1;
+        if (netif_queue_stopped(dev) && (greth->tx_free > (MAX_SKB_FRAGS+1)))
+                netif_wake_queue(dev);
 }
 
 static int greth_rx(struct net_device *dev, int limit)
@@ -727,20 +730,24 @@ static int greth_rx(struct net_device *dev, int limit)
         int pkt_len;
         int bad, count;
         u32 status, dma_addr;
+        unsigned long flags;
 
         greth = netdev_priv(dev);
 
         for (count = 0; count < limit; ++count) {
 
                 bdp = greth->rx_bd_base + greth->rx_cur;
+                GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
+                mb();
                 status = greth_read_bd(&bdp->stat);
-                dma_addr = greth_read_bd(&bdp->addr);
-                bad = 0;
 
                 if (unlikely(status & GRETH_BD_EN)) {
                         break;
                 }
 
+                dma_addr = greth_read_bd(&bdp->addr);
+                bad = 0;
+
                 /* Check status for errors. */
                 if (unlikely(status & GRETH_RXBD_STATUS)) {
                         if (status & GRETH_RXBD_ERR_FT) {
@@ -802,7 +809,9 @@ static int greth_rx(struct net_device *dev, int limit)
 
                 dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
 
+                spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
                 greth_enable_rx(greth);
+                spin_unlock_irqrestore(&greth->devlock, flags);
 
                 greth->rx_cur = NEXT_RX(greth->rx_cur);
         }
@@ -836,6 +845,7 @@ static int greth_rx_gbit(struct net_device *dev, int limit)
         int pkt_len;
         int bad, count = 0;
         u32 status, dma_addr;
+        unsigned long flags;
 
         greth = netdev_priv(dev);
 
@@ -843,6 +853,8 @@ static int greth_rx_gbit(struct net_device *dev, int limit)
 
                 bdp = greth->rx_bd_base + greth->rx_cur;
                 skb = greth->rx_skbuff[greth->rx_cur];
+                GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
+                mb();
                 status = greth_read_bd(&bdp->stat);
                 bad = 0;
 
@@ -865,10 +877,9 @@ static int greth_rx_gbit(struct net_device *dev, int limit)
                         }
                 }
 
-                /* Allocate new skb to replace current */
-                newskb = netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN);
-
-                if (!bad && newskb) {
+                /* Allocate new skb to replace current, not needed if the
+                 * current skb can be reused */
+                if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
                         skb_reserve(newskb, NET_IP_ALIGN);
 
                         dma_addr = dma_map_single(greth->dev,
@@ -905,11 +916,22 @@ static int greth_rx_gbit(struct net_device *dev, int limit)
                                 if (net_ratelimit())
                                         dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
                                 dev_kfree_skb(newskb);
+                                /* reusing current skb, so it is a drop */
                                 dev->stats.rx_dropped++;
                         }
+                } else if (bad) {
+                        /* Bad Frame transfer, the skb is reused */
+                        dev->stats.rx_dropped++;
                 } else {
+                        /* Failed Allocating a new skb. This is rather stupid
+                         * but the current "filled" skb is reused, as if
+                         * transfer failure. One could argue that RX descriptor
+                         * table handling should be divided into cleaning and
+                         * filling as the TX part of the driver
+                         */
                         if (net_ratelimit())
                                 dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
+                        /* reusing current skb, so it is a drop */
                         dev->stats.rx_dropped++;
                 }
 
@@ -920,7 +942,9 @@ static int greth_rx_gbit(struct net_device *dev, int limit)
 
                 wmb();
                 greth_write_bd(&bdp->stat, status);
+                spin_lock_irqsave(&greth->devlock, flags);
                 greth_enable_rx(greth);
+                spin_unlock_irqrestore(&greth->devlock, flags);
                 greth->rx_cur = NEXT_RX(greth->rx_cur);
         }
 
@@ -932,15 +956,18 @@ static int greth_poll(struct napi_struct *napi, int budget)
 {
         struct greth_private *greth;
         int work_done = 0;
+        unsigned long flags;
+        u32 mask, ctrl;
         greth = container_of(napi, struct greth_private, napi);
 
-        if (greth->gbit_mac) {
-                greth_clean_tx_gbit(greth->netdev);
-        } else {
-                greth_clean_tx(greth->netdev);
+restart_txrx_poll:
+        if (netif_queue_stopped(greth->netdev)) {
+                if (greth->gbit_mac)
+                        greth_clean_tx_gbit(greth->netdev);
+                else
+                        greth_clean_tx(greth->netdev);
         }
 
-restart_poll:
         if (greth->gbit_mac) {
                 work_done += greth_rx_gbit(greth->netdev, budget - work_done);
         } else {
@@ -949,15 +976,29 @@ restart_poll:
 
         if (work_done < budget) {
 
-                napi_complete(napi);
+                spin_lock_irqsave(&greth->devlock, flags);
+
+                ctrl = GRETH_REGLOAD(greth->regs->control);
+                if (netif_queue_stopped(greth->netdev)) {
+                        GRETH_REGSAVE(greth->regs->control,
+                                        ctrl | GRETH_TXI | GRETH_RXI);
+                        mask = GRETH_INT_RX | GRETH_INT_RE |
+                               GRETH_INT_TX | GRETH_INT_TE;
+                } else {
+                        GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
+                        mask = GRETH_INT_RX | GRETH_INT_RE;
+                }
 
-                if (greth_pending_packets(greth)) {
-                        napi_reschedule(napi);
-                        goto restart_poll;
+                if (GRETH_REGLOAD(greth->regs->status) & mask) {
+                        GRETH_REGSAVE(greth->regs->control, ctrl);
+                        spin_unlock_irqrestore(&greth->devlock, flags);
+                        goto restart_txrx_poll;
+                } else {
+                        __napi_complete(napi);
+                        spin_unlock_irqrestore(&greth->devlock, flags);
                 }
         }
 
-        greth_enable_irqs(greth);
         return work_done;
 }
 
@@ -1152,11 +1193,11 @@ static const struct ethtool_ops greth_ethtool_ops = {
 };
 
 static struct net_device_ops greth_netdev_ops = {
-        .ndo_open = greth_open,
-        .ndo_stop = greth_close,
-        .ndo_start_xmit = greth_start_xmit,
-        .ndo_set_mac_address = greth_set_mac_add,
-        .ndo_validate_addr      = eth_validate_addr,
+        .ndo_open               = greth_open,
+        .ndo_stop               = greth_close,
+        .ndo_start_xmit         = greth_start_xmit,
+        .ndo_set_mac_address    = greth_set_mac_add,
+        .ndo_validate_addr      = eth_validate_addr,
 };
 
 static inline int wait_for_mdio(struct greth_private *greth)
@@ -1217,29 +1258,26 @@ static void greth_link_change(struct net_device *dev)
         struct greth_private *greth = netdev_priv(dev);
         struct phy_device *phydev = greth->phy;
         unsigned long flags;
-
         int status_change = 0;
+        u32 ctrl;
 
         spin_lock_irqsave(&greth->devlock, flags);
 
         if (phydev->link) {
 
                 if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
-
-                        GRETH_REGANDIN(greth->regs->control,
-                                       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB));
+                        ctrl = GRETH_REGLOAD(greth->regs->control) &
+                               ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
 
                         if (phydev->duplex)
-                                GRETH_REGORIN(greth->regs->control, GRETH_CTRL_FD);
-
-                        if (phydev->speed == SPEED_100) {
-
-                                GRETH_REGORIN(greth->regs->control, GRETH_CTRL_SP);
-                        }
+                                ctrl |= GRETH_CTRL_FD;
 
+                        if (phydev->speed == SPEED_100)
+                                ctrl |= GRETH_CTRL_SP;
                         else if (phydev->speed == SPEED_1000)
-                                GRETH_REGORIN(greth->regs->control, GRETH_CTRL_GB);
+                                ctrl |= GRETH_CTRL_GB;
 
+                        GRETH_REGSAVE(greth->regs->control, ctrl);
                         greth->speed = phydev->speed;
                         greth->duplex = phydev->duplex;
                         status_change = 1;
@@ -1600,6 +1638,9 @@ static struct of_device_id greth_of_match[] = {
         {
          .name = "GAISLER_ETHMAC",
          },
+        {
+         .name = "01_01d",
+         },
         {},
 };