KumiSystems/openwrtv4
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

cns3xxx: fix ethernet driver tx completion and queue stop/start

Browse source 
SVN-Revision: 33504
This commit is contained in:
Felix Fietkau 2012-09-22 00:34:53 +00:00
parent fb71465a4e
commit d6ca46cd25
1 changed files with 110 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

110
target/linux/cns3xxx/patches-3.3/430-ethernet_fix_tx_completion.patch Normal file
View file

@ -0,0 +1,110 @@
--- a/drivers/net/ethernet/cavium/cns3xxx_eth.c
+++ b/drivers/net/ethernet/cavium/cns3xxx_eth.c
@@ -28,6 +28,7 @@
#define RX_DESCS 128
#define TX_DESCS 128
+#define TX_DESC_RESERVE 20
#define RX_POOL_ALLOC_SIZE (sizeof(struct rx_desc) * RX_DESCS)
#define TX_POOL_ALLOC_SIZE (sizeof(struct tx_desc) * TX_DESCS)
@@ -266,6 +267,7 @@ struct _tx_ring {
u32 cur_index;
int num_used;
int num_count;
+ bool stopped;
};
struct _rx_ring {
@@ -546,7 +548,34 @@ out:
rx_ring->alloc_index = i;
}
-static void clear_tx_desc(struct sw *sw)
+static void eth_check_num_used(struct _tx_ring *tx_ring)
+{
+ bool stop = false;
+ int i;
+
+ if (tx_ring->num_used >= TX_DESCS - TX_DESC_RESERVE)
+ stop = true;
+
+ if (tx_ring->stopped == stop)
+ return;
+
+ tx_ring->stopped = stop;
+ for (i = 0; i < 4; i++) {
+ struct port *port = switch_port_tab[i];
+ struct net_device *dev;
+
+ if (!port)
+ continue;
+
+ dev = port->netdev;
+ if (stop)
+ netif_stop_queue(dev);
+ else
+ netif_wake_queue(dev);
+ }
+}
+
+static void eth_complete_tx(struct sw *sw)
{
struct _tx_ring *tx_ring = sw->tx_ring;
struct tx_desc *desc;
@@ -555,9 +584,6 @@ static void clear_tx_desc(struct sw *sw)
int num_used = tx_ring->num_used;
struct sk_buff *skb;
- if (num_used < (TX_DESCS >> 1))
- return;
-
index = tx_ring->free_index;
desc = &(tx_ring)->desc[index];
for (i = 0; i < num_used; i++) {
@@ -580,6 +606,7 @@ static void clear_tx_desc(struct sw *sw)
}
tx_ring->free_index = index;
tx_ring->num_used -= i;
+ eth_check_num_used(tx_ring);
}
static int eth_poll(struct napi_struct *napi, int budget)
@@ -688,6 +715,10 @@ static int eth_poll(struct napi_struct *
enable_rx_dma(sw);
+ spin_lock_bh(&tx_lock);
+ eth_complete_tx(sw);
+ spin_unlock_bh(&tx_lock);
+
return received;
}
@@ -732,21 +763,19 @@ static int eth_xmit(struct sk_buff *skb,
skb_walk_frags(skb, skb1)
nr_desc++;
- spin_lock(&tx_lock);
+ spin_lock_bh(&tx_lock);
+ eth_complete_tx(sw);
if ((tx_ring->num_used + nr_desc + 1) >= TX_DESCS) {
- clear_tx_desc(sw);
- if ((tx_ring->num_used + nr_desc + 1) >= TX_DESCS) {
- spin_unlock(&tx_lock);
- return NETDEV_TX_BUSY;
- }
+ spin_unlock_bh(&tx_lock);
+ return NETDEV_TX_BUSY;
}
index = index0 = tx_ring->cur_index;
index_last = (index0 + nr_desc) % TX_DESCS;
tx_ring->cur_index = (index_last + 1) % TX_DESCS;
- spin_unlock(&tx_lock);
+ spin_unlock_bh(&tx_lock);
config0 = FORCE_ROUTE;
if (skb->ip_summed == CHECKSUM_PARTIAL)