enetc: Clean up Rx BD iteration

Improve maintainability of the code iterating the Rx buffer
descriptors to prepare it to support iterating extended Rx BD
descriptors as well.
Don't increment by one the h/w descriptor pointers explicitly,
provide an iterator that takes care of the h/w details.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 1f79e36116a39654da967e83fd2f470499af7989..f1bbaef428c0126378ef786a7d0c865a912d36b5 100644 (file)
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -451,7 +451,7 @@ static int enetc_refill_rx_ring(struct enetc_bdr *rx_ring, const int buff_cnt)
 
        i = rx_ring->next_to_use;
        rx_swbd = &rx_ring->rx_swbd[i];
-       rxbd = ENETC_RXBD(*rx_ring, i);
+       rxbd = enetc_rxbd(rx_ring, i);
 
        for (j = 0; j < buff_cnt; j++) {
                /* try reuse page */
@@ -468,13 +468,12 @@ static int enetc_refill_rx_ring(struct enetc_bdr *rx_ring, const int buff_cnt)
                /* clear 'R" as well */
                rxbd->r.lstatus = 0;
 
+               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
                rx_swbd++;
-               rxbd++;
                i++;
                if (unlikely(i == rx_ring->bd_count)) {
                        i = 0;
                        rx_swbd = rx_ring->rx_swbd;
-                       rxbd = ENETC_RXBD(*rx_ring, 0);
                }
        }
 
@@ -655,7 +654,7 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        cleaned_cnt -= count;
                }
 
-               rxbd = ENETC_RXBD(*rx_ring, i);
+               rxbd = enetc_rxbd(rx_ring, i);
                bd_status = le32_to_cpu(rxbd->r.lstatus);
                if (!bd_status)
                        break;
@@ -670,12 +669,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                enetc_get_offloads(rx_ring, rxbd, skb);
 
                cleaned_cnt++;
-               rxbd++;
-               i++;
-               if (unlikely(i == rx_ring->bd_count)) {
+
+               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+               if (unlikely(++i == rx_ring->bd_count))
                        i = 0;
-                       rxbd = ENETC_RXBD(*rx_ring, 0);
-               }
 
                if (unlikely(bd_status &
                             ENETC_RXBD_LSTATUS(ENETC_RXBD_ERR_MASK))) {
@@ -683,12 +680,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
                                dma_rmb();
                                bd_status = le32_to_cpu(rxbd->r.lstatus);
-                               rxbd++;
-                               i++;
-                               if (unlikely(i == rx_ring->bd_count)) {
+
+                               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+                               if (unlikely(++i == rx_ring->bd_count))
                                        i = 0;
-                                       rxbd = ENETC_RXBD(*rx_ring, 0);
-                               }
                        }
 
                        rx_ring->ndev->stats.rx_dropped++;
@@ -710,12 +705,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        enetc_add_rx_buff_to_skb(rx_ring, i, size, skb);
 
                        cleaned_cnt++;
-                       rxbd++;
-                       i++;
-                       if (unlikely(i == rx_ring->bd_count)) {
+
+                       rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+                       if (unlikely(++i == rx_ring->bd_count))
                                i = 0;
-                               rxbd = ENETC_RXBD(*rx_ring, 0);
-                       }
                }
 
                rx_byte_cnt += skb->len;

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.h b/drivers/net/ethernet/freescale/enetc/enetc.h
index 9938f7a5fc0a004dbdead758d81444e9dee8d17b..1cd4cddd5c583cf56495e2c53166e2492f174bbb 100644 (file)
--- a/drivers/net/ethernet/freescale/enetc/enetc.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc.h
@@ -104,7 +104,22 @@ struct enetc_cbdr {
 };
 
 #define ENETC_TXBD(BDR, i) (&(((union enetc_tx_bd *)((BDR).bd_base))[i]))
-#define ENETC_RXBD(BDR, i) (&(((union enetc_rx_bd *)((BDR).bd_base))[i]))
+
+static inline union enetc_rx_bd *enetc_rxbd(struct enetc_bdr *rx_ring, int i)
+{
+       return &(((union enetc_rx_bd *)rx_ring->bd_base)[i]);
+}
+
+static inline union enetc_rx_bd *enetc_rxbd_next(struct enetc_bdr *rx_ring,
+                                                union enetc_rx_bd *rxbd,
+                                                int i)
+{
+       rxbd++;
+       if (unlikely(++i == rx_ring->bd_count))
+               rxbd = rx_ring->bd_base;
+
+       return rxbd;
+}
 
 struct enetc_msg_swbd {
        void *vaddr;