net: fec: Increase buffer descriptor entry number

In order to support SG, software TSO, let's increase BD entry number.

CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 17 insertions, 16 deletions

diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index db967a08637d..5ffd32308b9c 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -246,8 +246,8 @@ struct bufdesc_ex {
 #define RX_RING_SIZE            (FEC_ENET_RX_FRPPG * FEC_ENET_RX_PAGES)
 #define FEC_ENET_TX_FRSIZE      2048
 #define FEC_ENET_TX_FRPPG       (PAGE_SIZE / FEC_ENET_TX_FRSIZE)
-#define TX_RING_SIZE            16      /* Must be power of two */
-#define TX_RING_MOD_MASK        15      /*   for this to work */
+#define TX_RING_SIZE            512     /* Must be power of two */
+#define TX_RING_MOD_MASK        511     /*   for this to work */
 
 #define BD_ENET_RX_INT          0x00800000
 #define BD_ENET_RX_PTP          ((ushort)0x0400)
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index f943cd142ef7..b27a729222b8 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -173,10 +173,6 @@ MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");
 #endif
 #endif /* CONFIG_M5272 */
 
-#if (((RX_RING_SIZE + TX_RING_SIZE) * 32) > PAGE_SIZE)
-#error "FEC: descriptor ring size constants too large"
-#endif
-
 /* Interrupt events/masks. */
 #define FEC_ENET_HBERR  ((uint)0x80000000)      /* Heartbeat error */
 #define FEC_ENET_BABR   ((uint)0x40000000)      /* Babbling receiver */
@@ -2048,9 +2044,21 @@ static int fec_enet_init(struct net_device *ndev)
         const struct platform_device_id *id_entry =
                                 platform_get_device_id(fep->pdev);
         struct bufdesc *cbd_base;
+        int bd_size;
+
+        /* init the tx & rx ring size */
+        fep->tx_ring_size = TX_RING_SIZE;
+        fep->rx_ring_size = RX_RING_SIZE;
+
+        if (fep->bufdesc_ex)
+                fep->bufdesc_size = sizeof(struct bufdesc_ex);
+        else
+                fep->bufdesc_size = sizeof(struct bufdesc);
+        bd_size = (fep->tx_ring_size + fep->rx_ring_size) *
+                        fep->bufdesc_size;
 
         /* Allocate memory for buffer descriptors. */
-        cbd_base = dma_alloc_coherent(NULL, PAGE_SIZE, &fep->bd_dma,
+        cbd_base = dma_alloc_coherent(NULL, bd_size, &fep->bd_dma,
                                       GFP_KERNEL);
         if (!cbd_base)
                 return -ENOMEM;
@@ -2064,20 +2072,13 @@ static int fec_enet_init(struct net_device *ndev)
         /* make sure MAC we just acquired is programmed into the hw */
         fec_set_mac_address(ndev, NULL);
 
-        /* init the tx & rx ring size */
-        fep->tx_ring_size = TX_RING_SIZE;
-        fep->rx_ring_size = RX_RING_SIZE;
-
         /* Set receive and transmit descriptor base. */
         fep->rx_bd_base = cbd_base;
-        if (fep->bufdesc_ex) {
+        if (fep->bufdesc_ex)
                 fep->tx_bd_base = (struct bufdesc *)
                         (((struct bufdesc_ex *)cbd_base) + fep->rx_ring_size);
-                fep->bufdesc_size = sizeof(struct bufdesc_ex);
-        } else {
+        else
                 fep->tx_bd_base = cbd_base + fep->rx_ring_size;
-                fep->bufdesc_size = sizeof(struct bufdesc);
-        }
 
         /* The FEC Ethernet specific entries in the device structure */
         ndev->watchdog_timeo = TX_TIMEOUT;