From 76d94b232940ca91e9b26c590cb7312ab88ff722 Mon Sep 17 00:00:00 2001 From: Tomoya Date: Sun, 12 Dec 2010 20:24:07 +0000 Subject: pch_can: Add flow control processing Currently, there is no flow control processing. Thus, Add flow control processing as when there is no empty of tx buffer, netif_stop_queue is called. When there is empty buffer, netif_wake_queue is called. Signed-off-by: Tomoya MORINAGA Signed-off-by: David S. Miller --- drivers/net/can/pch_can.c | 31 ++++++++++++------------------- 1 file changed, 12 insertions(+), 19 deletions(-) (limited to 'drivers/net/can') diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c index a9b6a6525a6..f0f140492c0 100644 --- a/drivers/net/can/pch_can.c +++ b/drivers/net/can/pch_can.c @@ -102,6 +102,10 @@ #define PCH_FIFO_THRESH 16 +/* TxRqst2 show status of MsgObjNo.17~32 */ +#define PCH_TREQ2_TX_MASK (((1 << PCH_TX_OBJ_NUM) - 1) <<\ + (PCH_RX_OBJ_END - 16)) + enum pch_ifreg { PCH_RX_IFREG, PCH_TX_IFREG, @@ -871,6 +875,8 @@ MSG_OBJ: dlc = 8; stats->tx_bytes += dlc; stats->tx_packets++; + if (int_stat == PCH_TX_OBJ_END) + netif_wake_queue(ndev); } int_stat = pch_can_int_pending(priv); @@ -1009,18 +1015,6 @@ static int pch_close(struct net_device *ndev) return 0; } -static int pch_get_msg_obj_sts(struct net_device *ndev, u32 obj_id) -{ - u32 buffer_status = 0; - struct pch_can_priv *priv = netdev_priv(ndev); - - /* Getting the message object status. */ - buffer_status = (u32) pch_can_get_buffer_status(priv); - - return buffer_status & obj_id; -} - - static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev) { int i, j; @@ -1031,17 +1025,16 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev) if (can_dropped_invalid_skb(ndev, skb)) return NETDEV_TX_OK; - if (priv->tx_obj == PCH_TX_OBJ_END) { /* Point tail Obj */ - while (pch_get_msg_obj_sts(ndev, (((1 << PCH_TX_OBJ_NUM)-1) << - PCH_RX_OBJ_NUM))) - udelay(500); + if (priv->tx_obj == PCH_TX_OBJ_END) { + if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK) + netif_stop_queue(ndev); - priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj ID */ - tx_buffer_avail = priv->tx_obj; /* Point Tail of Tx Obj */ + tx_buffer_avail = priv->tx_obj; + priv->tx_obj = PCH_TX_OBJ_START; } else { tx_buffer_avail = priv->tx_obj; + priv->tx_obj++; } - priv->tx_obj++; /* Reading the Msg Obj from the Msg RAM to the Interface register. */ iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask); -- cgit v1.2.3