[realtek] Fix reopening of legacy-mode 8139 NIC

realtek_destroy_ring() currently does nothing if the card is operating in legacy (pre-RTL8139C+) mode. In particular, the producer and consumer counters are incorrectly left holding their current values. Virtual hardware (e.g. the emulated RTL8139 in qemu and similar VMs) is tolerant of this behaviour, but real hardware will fail to transmit if the descriptors are not used in the correct order. Fix by resetting the producer and consumer counters in realtek_destroy_ring() even if the card is operating in legacy mode. Reported-by: Gelip <mrgelip@gmail.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
ipxe · May 26, 2013 · 5d3d62d · 5d3d62d
1 parent c4bce43
commit 5d3d62d
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/src/drivers/net/realtek.c b/src/drivers/net/realtek.c
@@ -549,7 +549,11 @@ static int realtek_create_ring ( struct realtek_nic *rtl,
 static void realtek_destroy_ring ( struct realtek_nic *rtl,
 				   struct realtek_ring *ring ) {
 
-	/* Do nothing in legacy mode */
+	/* Reset producer and consumer counters */
+	ring->prod = 0;
+	ring->cons = 0;
+
+	/* Do nothing more if in legacy mode */
 	if ( rtl->legacy )
 		return;
 
@@ -560,8 +564,6 @@ static void realtek_destroy_ring ( struct realtek_nic *rtl,
 	/* Free descriptor ring */
 	free_dma ( ring->desc, ring->len );
 	ring->desc = NULL;
-	ring->prod = 0;
-	ring->cons = 0;
 }
 
 /**