[BNX2]: More 5706S link down workaround.

The previous patches to workaround the 5706S on an HP blade were not
sufficient.  The link state still does not change properly in some
cases.  This patch adds polling to make it completely reliable.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bnx2.c

@@ -1273,14 +1273,20 @@ bnx2_set_link(struct bnx2 *bp)
 
 	if ((bp->phy_flags & BNX2_PHY_FLAG_SERDES) &&
 	    (CHIP_NUM(bp) == CHIP_NUM_5706)) {
-		u32 val;
+		u32 val, an_dbg;
 
 		if (bp->phy_flags & BNX2_PHY_FLAG_FORCED_DOWN) {
 			bnx2_5706s_force_link_dn(bp, 0);
 			bp->phy_flags &= ~BNX2_PHY_FLAG_FORCED_DOWN;
 		}
 		val = REG_RD(bp, BNX2_EMAC_STATUS);
-		if (val & BNX2_EMAC_STATUS_LINK)
+
+		bnx2_write_phy(bp, MII_BNX2_MISC_SHADOW, MISC_SHDW_AN_DBG);
+		bnx2_read_phy(bp, MII_BNX2_MISC_SHADOW, &an_dbg);
+		bnx2_read_phy(bp, MII_BNX2_MISC_SHADOW, &an_dbg);
+
+		if ((val & BNX2_EMAC_STATUS_LINK) &&
+		    !(an_dbg & MISC_SHDW_AN_DBG_NOSYNC))
 			bmsr |= BMSR_LSTATUS;
 		else
 			bmsr &= ~BMSR_LSTATUS;
@@ -5390,13 +5396,6 @@ bnx2_5706_serdes_timer(struct bnx2 *bp)
 	int check_link = 1;
 
 	spin_lock(&bp->phy_lock);
-	if (bp->phy_flags & BNX2_PHY_FLAG_FORCED_DOWN) {
-		bnx2_5706s_force_link_dn(bp, 0);
-		bp->phy_flags &= ~BNX2_PHY_FLAG_FORCED_DOWN;
-		spin_unlock(&bp->phy_lock);
-		return;
-	}
-
 	if (bp->serdes_an_pending) {
 		bp->serdes_an_pending--;
 		check_link = 0;
@@ -5420,7 +5419,6 @@ bnx2_5706_serdes_timer(struct bnx2 *bp)
 		 (bp->phy_flags & BNX2_PHY_FLAG_PARALLEL_DETECT)) {
 		u32 phy2;
 
-		check_link = 0;
 		bnx2_write_phy(bp, 0x17, 0x0f01);
 		bnx2_read_phy(bp, 0x15, &phy2);
 		if (phy2 & 0x20) {
@@ -5435,17 +5433,21 @@ bnx2_5706_serdes_timer(struct bnx2 *bp)
 	} else
 		bp->current_interval = bp->timer_interval;
 
-	if (bp->link_up && (bp->autoneg & AUTONEG_SPEED) && check_link) {
+	if (check_link) {
 		u32 val;
 
 		bnx2_write_phy(bp, MII_BNX2_MISC_SHADOW, MISC_SHDW_AN_DBG);
 		bnx2_read_phy(bp, MII_BNX2_MISC_SHADOW, &val);
 		bnx2_read_phy(bp, MII_BNX2_MISC_SHADOW, &val);
 
-		if (val & MISC_SHDW_AN_DBG_NOSYNC) {
-			bnx2_5706s_force_link_dn(bp, 1);
-			bp->phy_flags |= BNX2_PHY_FLAG_FORCED_DOWN;
-		}
+		if (bp->link_up && (val & MISC_SHDW_AN_DBG_NOSYNC)) {
+			if (!(bp->phy_flags & BNX2_PHY_FLAG_FORCED_DOWN)) {
+				bnx2_5706s_force_link_dn(bp, 1);
+				bp->phy_flags |= BNX2_PHY_FLAG_FORCED_DOWN;
+			} else
+				bnx2_set_link(bp);
+		} else if (!bp->link_up && !(val & MISC_SHDW_AN_DBG_NOSYNC))
+			bnx2_set_link(bp);
 	}
 	spin_unlock(&bp->phy_lock);
 }