pch_can: Improve rx processing

Replace complex "goto" to "do~while".
For easy to read/understand, it divides a rx function into some functions.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tomoya 2010-12-12 20:24:10 +00:00 committed by David S. Miller
parent 8ac9702b9d
commit 1d5b4b2778

View File

@ -698,83 +698,110 @@ static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
static int pch_can_rx_normal(struct net_device *ndev, u32 int_stat)
static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
{
if (obj_id < PCH_FIFO_THRESH) {
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
/* Clearing the Dir bit. */
pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
/* Clearing NewDat & IntPnd */
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_INTPND);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_id);
} else if (obj_id > PCH_FIFO_THRESH) {
pch_can_int_clr(priv, obj_id);
} else if (obj_id == PCH_FIFO_THRESH) {
int cnt;
for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
pch_can_int_clr(priv, cnt + 1);
}
}
static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
{
struct pch_can_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &(priv->ndev->stats);
struct sk_buff *skb;
struct can_frame *cf;
netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_MSGLOST);
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_id);
skb = alloc_can_err_skb(ndev, &cf);
if (!skb)
return;
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
stats->rx_over_errors++;
stats->rx_errors++;
netif_receive_skb(skb);
}
static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
{
u32 reg;
canid_t id;
u32 ide;
u32 rtr;
int i, k;
int rcv_pkts = 0;
struct sk_buff *skb;
struct can_frame *cf;
struct pch_can_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &(priv->ndev->stats);
int i;
u32 id2;
u16 data_reg;
/* Reading the messsage object from the Message RAM */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, int_stat);
do {
/* Reading the messsage object from the Message RAM */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, obj_num);
/* Reading the MCONT register. */
reg = ioread32(&priv->regs->ifregs[0].mcont);
reg &= 0xffff;
/* Reading the MCONT register. */
reg = ioread32(&priv->regs->ifregs[0].mcont);
if (reg & PCH_IF_MCONT_EOB)
break;
for (k = int_stat; !(reg & PCH_IF_MCONT_EOB); k++) {
/* If MsgLost bit set. */
if (reg & PCH_IF_MCONT_MSGLOST) {
dev_err(&priv->ndev->dev, "Msg Obj is overwritten.\n");
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_MSGLOST);
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
&priv->regs->ifregs[0].cmask);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, k);
skb = alloc_can_err_skb(ndev, &cf);
if (!skb)
return -ENOMEM;
priv->can.can_stats.error_passive++;
priv->can.state = CAN_STATE_ERROR_PASSIVE;
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
cf->data[2] |= CAN_ERR_PROT_OVERLOAD;
stats->rx_packets++;
stats->rx_bytes += cf->can_dlc;
netif_receive_skb(skb);
pch_can_rx_msg_lost(ndev, obj_num);
rcv_pkts++;
goto RX_NEXT;
quota--;
obj_num++;
continue;
} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
obj_num++;
continue;
}
if (!(reg & PCH_IF_MCONT_NEWDAT))
goto RX_NEXT;
skb = alloc_can_skb(priv->ndev, &cf);
if (!skb)
return -ENOMEM;
/* Get Received data */
ide = ((ioread32(&priv->regs->ifregs[0].id2)) & PCH_ID2_XTD) >>
14;
if (ide) {
id2 = ioread32(&priv->regs->ifregs[0].id2);
if (id2 & PCH_ID2_XTD) {
id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
id |= (((ioread32(&priv->regs->ifregs[0].id2)) &
0x1fff) << 16);
cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
id |= (((id2) & 0x1fff) << 16);
cf->can_id = id | CAN_EFF_FLAG;
} else {
id = (((ioread32(&priv->regs->ifregs[0].id2)) &
(CAN_SFF_MASK << 2)) >> 2);
cf->can_id = (id & CAN_SFF_MASK);
id = (id2 >> 2) & CAN_SFF_MASK;
cf->can_id = id;
}
rtr = (ioread32(&priv->regs->ifregs[0].id2) & PCH_ID2_DIR);
if (rtr) {
cf->can_dlc = 0;
if (id2 & PCH_ID2_DIR)
cf->can_id |= CAN_RTR_FLAG;
} else {
cf->can_dlc =
((ioread32(&priv->regs->ifregs[0].mcont)) & 0x0f);
}
cf->can_dlc = get_can_dlc((ioread32(&priv->regs->
ifregs[0].mcont)) & 0xF);
for (i = 0; i < cf->can_dlc; i += 2) {
data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
@ -785,33 +812,12 @@ static int pch_can_rx_normal(struct net_device *ndev, u32 int_stat)
netif_receive_skb(skb);
rcv_pkts++;
stats->rx_packets++;
quota--;
stats->rx_bytes += cf->can_dlc;
if (k < PCH_FIFO_THRESH) {
iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
/* Clearing the Dir bit. */
pch_can_bit_clear(&priv->regs->ifregs[0].id2,
PCH_ID2_DIR);
/* Clearing NewDat & IntPnd */
pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
PCH_IF_MCONT_INTPND);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, k);
} else if (k > PCH_FIFO_THRESH) {
pch_can_int_clr(priv, k);
} else if (k == PCH_FIFO_THRESH) {
int cnt;
for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
pch_can_int_clr(priv, cnt+1);
}
RX_NEXT:
/* Reading the messsage object from the Message RAM */
iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
pch_can_check_if_busy(&priv->regs->ifregs[0].creq, k);
reg = ioread32(&priv->regs->ifregs[0].mcont);
}
pch_fifo_thresh(priv, obj_num);
obj_num++;
} while (quota > 0);
return rcv_pkts;
}
@ -869,7 +875,7 @@ static int pch_can_rx_poll(struct napi_struct *napi, int quota)
goto end;
if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
rcv_pkts += pch_can_rx_normal(ndev, int_stat);
rcv_pkts += pch_can_rx_normal(ndev, int_stat, quota);
quota -= rcv_pkts;
if (quota < 0)
goto end;