From 1d5b4b2778e8e40f42ae5d9556777583f3556d81 Mon Sep 17 00:00:00 2001 From: Tomoya Date: Sun, 12 Dec 2010 20:24:10 +0000 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- drivers/net/can/pch_can.c | 158 ++++++++++++++++++++------------------ 1 file changed, 82 insertions(+), 76 deletions(-) diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c index 210957f093bb..d646fbcd546a 100644 --- a/drivers/net/can/pch_can.c +++ b/drivers/net/can/pch_can.c @@ -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; -- 2.20.1