mv643xx_eth: work around TX hang hardware issue
Under some conditions, the TXQ ('TX queue being served') bit can clear
before all packets queued for that TX queue have been transmitted.
This patch enables TXend interrupts, and uses those to re-kick TX
queues that claim to be idle but still have queued descriptors from
the interrupt handler.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Dale Farnsworth <dale@farnsworth.org>
diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c
index 287155e..c999157 100644
--- a/drivers/net/mv643xx_eth.c
+++ b/drivers/net/mv643xx_eth.c
@@ -96,6 +96,7 @@
#define TX_BW_MTU(p) (0x0458 + ((p) << 10))
#define TX_BW_BURST(p) (0x045c + ((p) << 10))
#define INT_CAUSE(p) (0x0460 + ((p) << 10))
+#define INT_TX_END 0x07f80000
#define INT_RX 0x0007fbfc
#define INT_EXT 0x00000002
#define INT_CAUSE_EXT(p) (0x0464 + ((p) << 10))
@@ -619,7 +620,7 @@
netif_rx_complete(mp->dev, napi);
wrl(mp, INT_CAUSE(mp->port_num), 0);
wrl(mp, INT_CAUSE_EXT(mp->port_num), 0);
- wrl(mp, INT_MASK(mp->port_num), INT_RX | INT_EXT);
+ wrl(mp, INT_MASK(mp->port_num), INT_TX_END | INT_RX | INT_EXT);
}
return rx;
@@ -1622,8 +1623,10 @@
struct mv643xx_eth_private *mp = netdev_priv(dev);
u32 int_cause;
u32 int_cause_ext;
+ u32 txq_active;
- int_cause = rdl(mp, INT_CAUSE(mp->port_num)) & (INT_RX | INT_EXT);
+ int_cause = rdl(mp, INT_CAUSE(mp->port_num)) &
+ (INT_TX_END | INT_RX | INT_EXT);
if (int_cause == 0)
return IRQ_NONE;
@@ -1675,6 +1678,8 @@
}
#endif
+ txq_active = rdl(mp, TXQ_COMMAND(mp->port_num));
+
/*
* TxBuffer or TxError set for any of the 8 queues?
*/
@@ -1684,8 +1689,28 @@
for (i = 0; i < 8; i++)
if (mp->txq_mask & (1 << i))
txq_reclaim(mp->txq + i, 0);
+ }
- __txq_maybe_wake(mp->txq + mp->txq_primary);
+ /*
+ * Any TxEnd interrupts?
+ */
+ if (int_cause & INT_TX_END) {
+ int i;
+
+ wrl(mp, INT_CAUSE(mp->port_num), ~(int_cause & INT_TX_END));
+ for (i = 0; i < 8; i++) {
+ struct tx_queue *txq = mp->txq + i;
+ if (txq->tx_desc_count && !((txq_active >> i) & 1))
+ txq_enable(txq);
+ }
+ }
+
+ /*
+ * Enough space again in the primary TX queue for a full packet?
+ */
+ if (int_cause_ext & INT_EXT_TX) {
+ struct tx_queue *txq = mp->txq + mp->txq_primary;
+ __txq_maybe_wake(txq);
}
return IRQ_HANDLED;
@@ -1869,7 +1894,7 @@
wrl(mp, INT_MASK_EXT(mp->port_num),
INT_EXT_LINK | INT_EXT_PHY | INT_EXT_TX);
- wrl(mp, INT_MASK(mp->port_num), INT_RX | INT_EXT);
+ wrl(mp, INT_MASK(mp->port_num), INT_TX_END | INT_RX | INT_EXT);
return 0;
@@ -2005,7 +2030,7 @@
mv643xx_eth_irq(dev->irq, dev);
- wrl(mp, INT_MASK(mp->port_num), INT_RX | INT_CAUSE_EXT);
+ wrl(mp, INT_MASK(mp->port_num), INT_TX_END | INT_RX | INT_CAUSE_EXT);
}
#endif