1 files changed, 54 insertions, 27 deletions

diff --git a/drivers/net/ethoc.c b/drivers/net/ethoc.c
index b7311bc00258..34d0c69e67f7 100644
--- a/drivers/net/ethoc.c
+++ b/drivers/net/ethoc.c
@@ -19,6 +19,10 @@
 #include <linux/platform_device.h>
 #include <net/ethoc.h>
 
+static int buffer_size = 0x8000; /* 32 KBytes */
+module_param(buffer_size, int, 0);
+MODULE_PARM_DESC(buffer_size, "DMA buffer allocation size");
+
 /* register offsets */
 #define MODER           0x00
 #define INT_SOURCE      0x04
@@ -167,6 +171,7 @@
  * struct ethoc - driver-private device structure
  * @iobase:     pointer to I/O memory region
  * @membase:    pointer to buffer memory region
+ * @dma_alloc:  dma allocated buffer size
  * @num_tx:     number of send buffers
  * @cur_tx:     last send buffer written
  * @dty_tx:     last buffer actually sent
@@ -185,6 +190,7 @@
 struct ethoc {
         void __iomem *iobase;
         void __iomem *membase;
+        int dma_alloc;
 
         unsigned int num_tx;
         unsigned int cur_tx;
@@ -284,7 +290,7 @@ static int ethoc_init_ring(struct ethoc *dev)
         dev->cur_rx = 0;
 
         /* setup transmission buffers */
-        bd.addr = 0;
+        bd.addr = virt_to_phys(dev->membase);
         bd.stat = TX_BD_IRQ | TX_BD_CRC;
 
         for (i = 0; i < dev->num_tx; i++) {
@@ -295,7 +301,6 @@ static int ethoc_init_ring(struct ethoc *dev)
                 bd.addr += ETHOC_BUFSIZ;
         }
 
-        bd.addr = dev->num_tx * ETHOC_BUFSIZ;
         bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
 
         for (i = 0; i < dev->num_rx; i++) {
@@ -400,8 +405,12 @@ static int ethoc_rx(struct net_device *dev, int limit)
                 if (ethoc_update_rx_stats(priv, &bd) == 0) {
                         int size = bd.stat >> 16;
                         struct sk_buff *skb = netdev_alloc_skb(dev, size);
+
+                        size -= 4; /* strip the CRC */
+                        skb_reserve(skb, 2); /* align TCP/IP header */
+
                         if (likely(skb)) {
-                                void *src = priv->membase + bd.addr;
+                                void *src = phys_to_virt(bd.addr);
                                 memcpy_fromio(skb_put(skb, size), src, size);
                                 skb->protocol = eth_type_trans(skb, dev);
                                 priv->stats.rx_packets++;
@@ -653,9 +662,9 @@ static int ethoc_open(struct net_device *dev)
         if (ret)
                 return ret;
 
-        /* calculate the number of TX/RX buffers */
-        num_bd = (dev->mem_end - dev->mem_start + 1) / ETHOC_BUFSIZ;
-        priv->num_tx = min(min_tx, num_bd / 4);
+        /* calculate the number of TX/RX buffers, maximum 128 supported */
+        num_bd = min(128, (dev->mem_end - dev->mem_start + 1) / ETHOC_BUFSIZ);
+        priv->num_tx = max(min_tx, num_bd / 4);
         priv->num_rx = num_bd - priv->num_tx;
         ethoc_write(priv, TX_BD_NUM, priv->num_tx);
 
@@ -823,7 +832,7 @@ static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
         else
                 bd.stat &= ~TX_BD_PAD;
 
-        dest = priv->membase + bd.addr;
+        dest = phys_to_virt(bd.addr);
         memcpy_toio(dest, skb->data, skb->len);
 
         bd.stat &= ~(TX_BD_STATS | TX_BD_LEN_MASK);
@@ -903,22 +912,19 @@ static int ethoc_probe(struct platform_device *pdev)
 
         /* obtain buffer memory space */
         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-        if (!res) {
-                dev_err(&pdev->dev, "cannot obtain memory space\n");
-                ret = -ENXIO;
-                goto free;
-        }
-
-        mem = devm_request_mem_region(&pdev->dev, res->start,
+        if (res) {
+                mem = devm_request_mem_region(&pdev->dev, res->start,
                         res->end - res->start + 1, res->name);
-        if (!mem) {
-                dev_err(&pdev->dev, "cannot request memory space\n");
-                ret = -ENXIO;
-                goto free;
+                if (!mem) {
+                        dev_err(&pdev->dev, "cannot request memory space\n");
+                        ret = -ENXIO;
+                        goto free;
+                }
+
+                netdev->mem_start = mem->start;
+                netdev->mem_end   = mem->end;
         }
 
-        netdev->mem_start = mem->start;
-        netdev->mem_end   = mem->end;
 
         /* obtain device IRQ number */
         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
@@ -933,6 +939,7 @@ static int ethoc_probe(struct platform_device *pdev)
         /* setup driver-private data */
         priv = netdev_priv(netdev);
         priv->netdev = netdev;
+        priv->dma_alloc = 0;
 
         priv->iobase = devm_ioremap_nocache(&pdev->dev, netdev->base_addr,
                         mmio->end - mmio->start + 1);
@@ -942,12 +949,27 @@ static int ethoc_probe(struct platform_device *pdev)
                 goto error;
         }
 
-        priv->membase = devm_ioremap_nocache(&pdev->dev, netdev->mem_start,
-                        mem->end - mem->start + 1);
-        if (!priv->membase) {
-                dev_err(&pdev->dev, "cannot remap memory space\n");
-                ret = -ENXIO;
-                goto error;
+        if (netdev->mem_end) {
+                priv->membase = devm_ioremap_nocache(&pdev->dev,
+                        netdev->mem_start, mem->end - mem->start + 1);
+                if (!priv->membase) {
+                        dev_err(&pdev->dev, "cannot remap memory space\n");
+                        ret = -ENXIO;
+                        goto error;
+                }
+        } else {
+                /* Allocate buffer memory */
+                priv->membase = dma_alloc_coherent(NULL,
+                        buffer_size, (void *)&netdev->mem_start,
+                        GFP_KERNEL);
+                if (!priv->membase) {
+                        dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
+                                buffer_size);
+                        ret = -ENOMEM;
+                        goto error;
+                }
+                netdev->mem_end = netdev->mem_start + buffer_size;
+                priv->dma_alloc = buffer_size;
         }
 
         /* Allow the platform setup code to pass in a MAC address. */
@@ -1034,6 +1056,9 @@ free_mdio:
         kfree(priv->mdio->irq);
         mdiobus_free(priv->mdio);
 free:
+        if (priv->dma_alloc)
+                dma_free_coherent(NULL, priv->dma_alloc, priv->membase,
+                        netdev->mem_start);
         free_netdev(netdev);
 out:
         return ret;
@@ -1059,7 +1084,9 @@ static int ethoc_remove(struct platform_device *pdev)
                         kfree(priv->mdio->irq);
                         mdiobus_free(priv->mdio);
                 }
-
+                if (priv->dma_alloc)
+                        dma_free_coherent(NULL, priv->dma_alloc, priv->membase,
+                                netdev->mem_start);
                 unregister_netdev(netdev);
                 free_netdev(netdev);
         }