[PATCH] sky2: transmit complete index optimization

Change transmit complete handling to use the status values
in the poll list because they are in-cache, rather than reading
non-cached memory for chips status.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 19 insertions, 16 deletions

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 8dfd27d4d6e5..ff6557dd079c 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1274,7 +1274,7 @@ out:
 }
 
 /* Cleanup all untransmitted buffers, assume transmitter not running */
-static inline void sky2_tx_clean(struct sky2_port *sky2)
+static void sky2_tx_clean(struct sky2_port *sky2)
 {
         sky2_tx_complete(sky2, sky2->tx_prod);
 }
@@ -1714,14 +1714,16 @@ error:
 /*
  * Check for transmit complete
  */
-static inline void sky2_tx_check(struct sky2_hw *hw, int port)
-{
-        struct net_device *dev = hw->dev[port];
+#define TX_NO_STATUS    0xffff
 
-        if (dev && netif_running(dev)) {
-                sky2_tx_complete(netdev_priv(dev),
-                                 sky2_read16(hw, port == 0
-                                             ? STAT_TXA1_RIDX : STAT_TXA2_RIDX));
+static inline void sky2_tx_check(struct sky2_hw *hw, int port, u16 last)
+{
+        if (last != TX_NO_STATUS) {
+                struct net_device *dev = hw->dev[port];
+                if (dev && netif_running(dev)) {
+                        struct sky2_port *sky2 = netdev_priv(dev);
+                        sky2_tx_complete(sky2, last);
+                }
         }
 }
 
@@ -1735,6 +1737,7 @@ static int sky2_poll(struct net_device *dev0, int *budget)
         unsigned int to_do = min(dev0->quota, *budget);
         unsigned int work_done = 0;
         u16 hwidx;
+        u16 tx_done[2] = { TX_NO_STATUS, TX_NO_STATUS };
 
         sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
         hwidx = sky2_read16(hw, STAT_PUT_IDX);
@@ -1806,7 +1809,10 @@ static int sky2_poll(struct net_device *dev0, int *budget)
                         break;
 
                 case OP_TXINDEXLE:
-                        /* pick up transmit status later */
+                        /* TX index reports status for both ports */
+                        tx_done[0] = status & 0xffff;
+                        tx_done[1] = ((status >> 24) & 0xff)
+                                | (u16)(length & 0xf) << 8;
                         break;
 
                 default:
@@ -1818,16 +1824,13 @@ static int sky2_poll(struct net_device *dev0, int *budget)
         }
 
 exit_loop:
-        sky2_tx_check(hw, 0);
-        sky2_tx_check(hw, 1);
-
         mmiowb();
 
+        sky2_tx_check(hw, 0, tx_done[0]);
+        sky2_tx_check(hw, 1, tx_done[1]);
+
         if (work_done < to_do) {
-                /*
-                 * Another chip workaround, need to restart TX timer if status
-                 * LE was handled. WA_DEV_43_418
-                 */
+                /* need to restart TX timer */
                 if (is_ec_a1(hw)) {
                         sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_STOP);
                         sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START);