From 34701fde8f4bf207ca96d10b8700a8667157854c Mon Sep 17 00:00:00 2001
From: Divy Le Ray <divy@chelsio.com>
Date: Tue, 7 Jul 2009 19:48:32 +0000
Subject: [PATCH] cxgb3: Drain Mac Tx fifo when the port goes down.
Drain the MAC TX fifos when a port goes down.
Back pressure might otherwise occur, leading to both
ports of the same adapter to hang.
Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/cxgb3/cxgb3_main.c | 29 ++++++++++++++++++++++++++++-
1 file changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/net/cxgb3/cxgb3_main.c b/drivers/net/cxgb3/cxgb3_main.c
index d4c4076cf087..8c381c696a3d 100644
--- a/drivers/net/cxgb3/cxgb3_main.c
+++ b/drivers/net/cxgb3/cxgb3_main.c
@@ -172,6 +172,23 @@ static void link_report(struct net_device *dev)
}
}
+static void enable_tx_fifo_drain(struct adapter *adapter,
+ struct port_info *pi)
+{
+ t3_set_reg_field(adapter, A_XGM_TXFIFO_CFG + pi->mac.offset, 0,
+ F_ENDROPPKT);
+ t3_write_reg(adapter, A_XGM_RX_CTRL + pi->mac.offset, 0);
+ t3_write_reg(adapter, A_XGM_TX_CTRL + pi->mac.offset, F_TXEN);
+ t3_write_reg(adapter, A_XGM_RX_CTRL + pi->mac.offset, F_RXEN);
+}
+
+static void disable_tx_fifo_drain(struct adapter *adapter,
+ struct port_info *pi)
+{
+ t3_set_reg_field(adapter, A_XGM_TXFIFO_CFG + pi->mac.offset,
+ F_ENDROPPKT, 0);
+}
+
void t3_os_link_fault(struct adapter *adap, int port_id, int state)
{
struct net_device *dev = adap->port[port_id];
@@ -185,6 +202,8 @@ void t3_os_link_fault(struct adapter *adap, int port_id, int state)
netif_carrier_on(dev);
+ disable_tx_fifo_drain(adap, pi);
+
/* Clear local faults */
t3_xgm_intr_disable(adap, pi->port_id);
t3_read_reg(adap, A_XGM_INT_STATUS +
@@ -200,9 +219,12 @@ void t3_os_link_fault(struct adapter *adap, int port_id, int state)
t3_xgm_intr_enable(adap, pi->port_id);
t3_mac_enable(mac, MAC_DIRECTION_TX);
- } else
+ } else {
netif_carrier_off(dev);
+ /* Flush TX FIFO */
+ enable_tx_fifo_drain(adap, pi);
+ }
link_report(dev);
}
@@ -232,6 +254,8 @@ void t3_os_link_changed(struct adapter *adapter, int port_id, int link_stat,
if (link_stat != netif_carrier_ok(dev)) {
if (link_stat) {
+ disable_tx_fifo_drain(adapter, pi);
+
t3_mac_enable(mac, MAC_DIRECTION_RX);
/* Clear local faults */
@@ -263,6 +287,9 @@ void t3_os_link_changed(struct adapter *adapter, int port_id, int link_stat,
t3_read_reg(adapter, A_XGM_INT_STATUS + pi->mac.offset);
t3_mac_disable(mac, MAC_DIRECTION_RX);
t3_link_start(&pi->phy, mac, &pi->link_config);
+
+ /* Flush TX FIFO */
+ enable_tx_fifo_drain(adapter, pi);
}
link_report(dev);