priv->raminit(priv, enable);
}
-static inline int get_tx_next_msg_obj(const struct c_can_priv *priv)
-{
- return (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) +
- C_CAN_MSG_OBJ_TX_FIRST;
-}
-
-static inline int get_tx_echo_msg_obj(int txecho)
-{
- return (txecho & C_CAN_NEXT_MSG_OBJ_MASK) + C_CAN_MSG_OBJ_TX_FIRST;
-}
-
-static u32 c_can_read_reg32(struct c_can_priv *priv, enum reg index)
-{
- u32 val = priv->read_reg(priv, index);
- val |= ((u32) priv->read_reg(priv, index + 1)) << 16;
- return val;
-}
-
static void c_can_irq_control(struct c_can_priv *priv, bool enable)
{
u32 ctrl = priv->read_reg(priv, C_CAN_CTRL_REG) & ~CONTROL_IRQMSK;
c_can_obj_update(dev, iface, cmd | IF_COMM_WR, obj);
}
-static void c_can_write_msg_object(struct net_device *dev, int iface,
- struct can_frame *frame, int obj)
+static void c_can_setup_tx_object(struct net_device *dev, int iface,
+ struct can_frame *frame, int obj)
{
struct c_can_priv *priv = netdev_priv(dev);
u16 ctrl = IF_MCONT_TX | frame->can_dlc;
priv->write_reg(priv, C_CAN_IFACE(DATA1_REG, iface) + i / 2,
frame->data[i] | (frame->data[i + 1] << 8));
}
-
- c_can_object_put(dev, iface, obj, IF_COMM_TX);
}
static inline void c_can_activate_all_lower_rx_msg_obj(struct net_device *dev,
c_can_object_put(dev, iface, obj, IF_COMM_INVAL);
}
-static inline int c_can_is_next_tx_obj_busy(struct c_can_priv *priv, int objno)
-{
- int val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG);
-
- /*
- * as transmission request register's bit n-1 corresponds to
- * message object n, we need to handle the same properly.
- */
- if (val & (1 << (objno - 1)))
- return 1;
-
- return 0;
-}
-
static netdev_tx_t c_can_start_xmit(struct sk_buff *skb,
- struct net_device *dev)
+ struct net_device *dev)
{
- u32 msg_obj_no;
- struct c_can_priv *priv = netdev_priv(dev);
struct can_frame *frame = (struct can_frame *)skb->data;
+ struct c_can_priv *priv = netdev_priv(dev);
+ u32 idx, obj;
if (can_dropped_invalid_skb(dev, skb))
return NETDEV_TX_OK;
-
- spin_lock_bh(&priv->xmit_lock);
- msg_obj_no = get_tx_next_msg_obj(priv);
-
- /* prepare message object for transmission */
- c_can_write_msg_object(dev, IF_TX, frame, msg_obj_no);
- priv->dlc[msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST] = frame->can_dlc;
- can_put_echo_skb(skb, dev, msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
-
/*
- * we have to stop the queue in case of a wrap around or
- * if the next TX message object is still in use
+ * This is not a FIFO. C/D_CAN sends out the buffers
+ * prioritized. The lowest buffer number wins.
*/
- priv->tx_next++;
- if (c_can_is_next_tx_obj_busy(priv, get_tx_next_msg_obj(priv)) ||
- (priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) == 0)
+ idx = fls(atomic_read(&priv->tx_active));
+ obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
+
+ /* If this is the last buffer, stop the xmit queue */
+ if (idx == C_CAN_MSG_OBJ_TX_NUM - 1)
netif_stop_queue(dev);
- spin_unlock_bh(&priv->xmit_lock);
+ /*
+ * Store the message in the interface so we can call
+ * can_put_echo_skb(). We must do this before we enable
+ * transmit as we might race against do_tx().
+ */
+ c_can_setup_tx_object(dev, IF_TX, frame, obj);
+ priv->dlc[idx] = frame->can_dlc;
+ can_put_echo_skb(skb, dev, idx);
+
+ /* Update the active bits */
+ atomic_add((1 << idx), &priv->tx_active);
+ /* Start transmission */
+ c_can_object_put(dev, IF_TX, obj, IF_COMM_TX);
return NETDEV_TX_OK;
}
/* set a `lec` value so that we can check for updates later */
priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED);
+ /* Clear all internal status */
+ atomic_set(&priv->tx_active, 0);
+ priv->rxmasked = 0;
+
/* set bittiming params */
return c_can_set_bittiming(dev);
}
priv->can.state = CAN_STATE_ERROR_ACTIVE;
- /* reset tx helper pointers and the rx mask */
- priv->tx_next = priv->tx_echo = 0;
- priv->rxmasked = 0;
-
return 0;
}
return err;
}
-/*
- * priv->tx_echo holds the number of the oldest can_frame put for
- * transmission into the hardware, but not yet ACKed by the CAN tx
- * complete IRQ.
- *
- * We iterate from priv->tx_echo to priv->tx_next and check if the
- * packet has been transmitted, echo it back to the CAN framework.
- * If we discover a not yet transmitted packet, stop looking for more.
- */
static void c_can_do_tx(struct net_device *dev)
{
struct c_can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
- u32 val, obj, pkts = 0, bytes = 0;
+ u32 idx, obj, pkts = 0, bytes = 0, pend, clr;
- spin_lock_bh(&priv->xmit_lock);
+ clr = pend = priv->read_reg(priv, C_CAN_INTPND2_REG);
- for (; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
- obj = get_tx_echo_msg_obj(priv->tx_echo);
- val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG);
-
- if (val & (1 << (obj - 1)))
- break;
-
- can_get_echo_skb(dev, obj - C_CAN_MSG_OBJ_TX_FIRST);
- bytes += priv->dlc[obj - C_CAN_MSG_OBJ_TX_FIRST];
+ while ((idx = ffs(pend))) {
+ idx--;
+ pend &= ~(1 << idx);
+ obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
+ c_can_inval_msg_object(dev, IF_RX, obj);
+ can_get_echo_skb(dev, idx);
+ bytes += priv->dlc[idx];
pkts++;
- c_can_inval_msg_object(dev, IF_TX, obj);
}
- /* restart queue if wrap-up or if queue stalled on last pkt */
- if (((priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) != 0) ||
- ((priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) == 0))
- netif_wake_queue(dev);
+ /* Clear the bits in the tx_active mask */
+ atomic_sub(clr, &priv->tx_active);
- spin_unlock_bh(&priv->xmit_lock);
+ if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1)))
+ netif_wake_queue(dev);
if (pkts) {
stats->tx_bytes += bytes;
return NULL;
priv = netdev_priv(dev);
- spin_lock_init(&priv->xmit_lock);
netif_napi_add(dev, &priv->napi, c_can_poll, C_CAN_NAPI_WEIGHT);
priv->dev = dev;
projects / openwrt / staging / blogic.git / commitdiff