[PATCH] sky2: write barrier's

Be more careful about memory barriers. The only place we really
need them is before and after updating the chip's ring interface.

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

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 178249a96e1c225f83de9844007edeeb04e0b393..1407ff2da41e060e618070a98f517b58bc17bc20 100644 (file)
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -707,6 +707,7 @@ static inline struct sky2_tx_le *get_tx_le(struct sky2_port *sky2)
 static inline void sky2_put_idx(struct sky2_hw *hw, unsigned q,
                                u16 idx, u16 *last, u16 size)
 {
+       wmb();
        if (is_ec_a1(hw) && idx < *last) {
                u16 hwget = sky2_read16(hw, Y2_QADDR(q, PREF_UNIT_GET_IDX));
 
@@ -730,6 +731,7 @@ setnew:
                sky2_write16(hw, Y2_QADDR(q, PREF_UNIT_PUT_IDX), idx);
        }
        *last = idx;
+       mmiowb();
 }
 
 
@@ -1253,7 +1255,6 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev)
                netif_stop_queue(dev);
 
 out_unlock:
-       mmiowb();
        spin_unlock(&sky2->tx_lock);
 
        dev->trans_start = jiffies;
@@ -1896,7 +1897,6 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 
 exit_loop:
        sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
-       mmiowb();
 
        sky2_tx_check(hw, 0, tx_done[0]);
        sky2_tx_check(hw, 1, tx_done[1]);
@@ -1911,7 +1911,6 @@ exit_loop:
                netif_rx_complete(dev0);
                hw->intr_mask |= Y2_IS_STAT_BMU;
                sky2_write32(hw, B0_IMSK, hw->intr_mask);
-               mmiowb();
                return 0;
        } else {
                *budget -= work_done;