[PATCH net-next V3 09/16] net: fec: eliminate calls to fec_enet_get_prevdesc

[Troy Kisky]

Eliminating calls to fec_enet_get_prevdesc shrinks
the code a little.

Signed-off-by: Troy Kisky <troy.ki...@boundarydevices.com>

---
v3: Change commit message

s/unsigned status/unsigned int status/ as requested
---
 drivers/net/ethernet/freescale/fec_main.c | 37 +++++++++----------------------
 1 file changed, 11 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c 
b/drivers/net/ethernet/freescale/fec_main.c
index 21d2cd0..349fda1 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -758,6 +758,7 @@ static void fec_enet_bd_init(struct net_device *dev)
        struct bufdesc *bdp;
        unsigned int i;
        unsigned int q;
+       unsigned int status;
 
        for (q = 0; q < fep->num_rx_queues; q++) {
                /* Initialize the receive buffer descriptors. */
@@ -765,19 +766,13 @@ static void fec_enet_bd_init(struct net_device *dev)
                bdp = rxq->bd.base;
 
                for (i = 0; i < rxq->bd.ring_size; i++) {
-
                        /* Initialize the BD for every fragment in the page. */
-                       if (bdp->cbd_bufaddr)
-                               bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY);
-                       else
-                               bdp->cbd_sc = cpu_to_fec16(0);
+                       status = bdp->cbd_bufaddr ? BD_ENET_RX_EMPTY : 0;
+                       if (bdp == rxq->bd.last)
+                               status |= BD_SC_WRAP;
+                       bdp->cbd_sc = cpu_to_fec16(status);
                        bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);
                }
-
-               /* Set the last buffer to wrap */
-               bdp = fec_enet_get_prevdesc(bdp, &rxq->bd);
-               bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
-
                rxq->bd.cur = rxq->bd.base;
        }
 
@@ -789,18 +784,16 @@ static void fec_enet_bd_init(struct net_device *dev)
 
                for (i = 0; i < txq->bd.ring_size; i++) {
                        /* Initialize the BD for every fragment in the page. */
-                       bdp->cbd_sc = cpu_to_fec16(0);
                        if (txq->tx_skbuff[i]) {
                                dev_kfree_skb_any(txq->tx_skbuff[i]);
                                txq->tx_skbuff[i] = NULL;
                        }
                        bdp->cbd_bufaddr = cpu_to_fec32(0);
+                       bdp->cbd_sc = cpu_to_fec16((bdp == txq->bd.last) ?
+                                       BD_SC_WRAP : 0);
                        bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                }
-
-               /* Set the last buffer to wrap */
                bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
-               bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
                txq->dirty_tx = bdp;
        }
 }
@@ -2717,19 +2710,16 @@ fec_enet_alloc_rxq_buffers(struct net_device *ndev, 
unsigned int queue)
                }
 
                rxq->rx_skbuff[i] = skb;
-               bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY);
 
                if (fep->bufdesc_ex) {
                        struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;
                        ebdp->cbd_esc = cpu_to_fec32(BD_ENET_RX_INT);
                }
+               bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY |
+                               ((bdp == rxq->bd.last) ? BD_SC_WRAP : 0));
 
                bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);
        }
-
-       /* Set the last buffer to wrap. */
-       bdp = fec_enet_get_prevdesc(bdp, &rxq->bd);
-       bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
        return 0;
 
  err_alloc:
@@ -2752,21 +2742,16 @@ fec_enet_alloc_txq_buffers(struct net_device *ndev, 
unsigned int queue)
                if (!txq->tx_bounce[i])
                        goto err_alloc;
 
-               bdp->cbd_sc = cpu_to_fec16(0);
                bdp->cbd_bufaddr = cpu_to_fec32(0);
 
                if (fep->bufdesc_ex) {
                        struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;
                        ebdp->cbd_esc = cpu_to_fec32(BD_ENET_TX_INT);
                }
-
+               bdp->cbd_sc = cpu_to_fec16((bdp == txq->bd.last) ?
+                               BD_SC_WRAP : 0);
                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
        }
-
-       /* Set the last buffer to wrap. */
-       bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
-       bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
-
        return 0;
 
  err_alloc:
-- 
2.5.0