net: systemport: Pre-calculate and utilize cb->bd_addr

There is a 1:1 mapping between the software maintained control block in
priv->rx_cbs and the buffer address in priv->rx_bds, such that there is
no need to keep computing the buffer address when refiling a control
block.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 9 insertions, 11 deletions

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index 084a50a555de..267330ccd595 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -549,12 +549,7 @@ static int bcm_sysport_rx_refill(struct bcm_sysport_priv *priv,
         }
 
         dma_unmap_addr_set(cb, dma_addr, mapping);
-        dma_desc_set_addr(priv, priv->rx_bd_assign_ptr, mapping);
-
-        priv->rx_bd_assign_index++;
-        priv->rx_bd_assign_index &= (priv->num_rx_bds - 1);
-        priv->rx_bd_assign_ptr = priv->rx_bds +
-                (priv->rx_bd_assign_index * DESC_SIZE);
+        dma_desc_set_addr(priv, cb->bd_addr, mapping);
 
         netif_dbg(priv, rx_status, ndev, "RX refill\n");
 
@@ -568,7 +563,7 @@ static int bcm_sysport_alloc_rx_bufs(struct bcm_sysport_priv *priv)
         unsigned int i;
 
         for (i = 0; i < priv->num_rx_bds; i++) {
-                cb = &priv->rx_cbs[priv->rx_bd_assign_index];
+                cb = &priv->rx_cbs[i];
                 if (cb->skb)
                         continue;
 
@@ -1330,14 +1325,14 @@ static inline int tdma_enable_set(struct bcm_sysport_priv *priv,
 
 static int bcm_sysport_init_rx_ring(struct bcm_sysport_priv *priv)
 {
+        struct bcm_sysport_cb *cb;
         u32 reg;
         int ret;
+        int i;
 
         /* Initialize SW view of the RX ring */
         priv->num_rx_bds = NUM_RX_DESC;
         priv->rx_bds = priv->base + SYS_PORT_RDMA_OFFSET;
-        priv->rx_bd_assign_ptr = priv->rx_bds;
-        priv->rx_bd_assign_index = 0;
         priv->rx_c_index = 0;
         priv->rx_read_ptr = 0;
         priv->rx_cbs = kcalloc(priv->num_rx_bds, sizeof(struct bcm_sysport_cb),
@@ -1347,6 +1342,11 @@ static int bcm_sysport_init_rx_ring(struct bcm_sysport_priv *priv)
                 return -ENOMEM;
         }
 
+        for (i = 0; i < priv->num_rx_bds; i++) {
+                cb = priv->rx_cbs + i;
+                cb->bd_addr = priv->rx_bds + i * DESC_SIZE;
+        }
+
         ret = bcm_sysport_alloc_rx_bufs(priv);
         if (ret) {
                 netif_err(priv, hw, priv->netdev, "SKB allocation failed\n");
diff --git a/drivers/net/ethernet/broadcom/bcmsysport.h b/drivers/net/ethernet/broadcom/bcmsysport.h
index 42a4b4a0bc14..f28bf545d7f4 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.h
+++ b/drivers/net/ethernet/broadcom/bcmsysport.h
@@ -663,8 +663,6 @@ struct bcm_sysport_priv {
 
         /* Receive queue */
         void __iomem            *rx_bds;
-        void __iomem            *rx_bd_assign_ptr;
-        unsigned int            rx_bd_assign_index;
         struct bcm_sysport_cb   *rx_cbs;
         unsigned int            num_rx_bds;
         unsigned int            rx_read_ptr;