[PATCH] use mmiowb in tg3.c

[Jesse Barnes]

This patch originally from Greg Banks.  Some parts of the tg3 driver depend on 
PIO writes arriving in order.  This patch ensures that in two key places 
using the new mmiowb macro.  This not only prevents bugs (the queues can be 
corrupted), but is much faster than ensuring ordering using PIO reads (which 
involve a few round trips to the target bus on some platforms).

Arthur has another patch that uses mmiowb in tg3 that he posted earlier as 
well.

Signed-off-by: Greg Banks <gnb@xxxxxxx>
Signed-off-by: Jesse Barnes <jbarnes@xxxxxxx

Thanks,
Jesse
===== drivers/net/tg3.c 1.210 vs edited =====
--- 1.210/drivers/net/tg3.c	2004-10-06 09:42:56 -07:00
+++ edited/drivers/net/tg3.c	2004-10-21 16:06:37 -07:00
@@ -2729,6 +2729,7 @@
 		tw32_rx_mbox(MAILBOX_RCV_JUMBO_PROD_IDX + TG3_64BIT_REG_LOW,
 			     sw_idx);
 	}
+	mmiowb();
 
 	return received;
 }
@@ -3176,6 +3177,7 @@
 		netif_stop_queue(dev);
 
 out_unlock:
+    	mmiowb();
 	spin_unlock_irqrestore(&tp->tx_lock, flags);
 
 	dev->trans_start = jiffies;