On 06/27/2014 12:00 PM, Dong Aisheng wrote:
> Add bus error, state change, lost message handling mechanism.
>
> Signed-off-by: Dong Aisheng <b29396@xxxxxxxxxxxxx>
> ---
> drivers/net/can/m_can.c | 271 +++++++++++++++++++++++++++++++++++++++++------
> 1 files changed, 240 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/net/can/m_can.c b/drivers/net/can/m_can.c
> index 61e9a8e..e4aed71 100644
> --- a/drivers/net/can/m_can.c
> +++ b/drivers/net/can/m_can.c
> @@ -83,6 +83,18 @@ enum m_can_reg {
> M_CAN_TXEFA = 0xf8,
> };
>
> +/* m_can lec values */
> +enum m_can_lec_type {
> + LEC_NO_ERROR = 0,
> + LEC_STUFF_ERROR,
> + LEC_FORM_ERROR,
> + LEC_ACK_ERROR,
> + LEC_BIT1_ERROR,
> + LEC_BIT0_ERROR,
> + LEC_CRC_ERROR,
> + LEC_UNUSED,
> +};
> +
> /* CC Control Register(CCCR) */
> #define CCCR_CCE BIT(1)
> #define CCCR_INIT BIT(0)
> @@ -97,6 +109,19 @@ enum m_can_reg {
> #define BTR_SJW_SHIFT 0
> #define BTR_SJW_MASK 0xf
>
> +/* Error Counter Register(ECR) */
> +#define ECR_RP BIT(15)
> +#define ECR_REC_SHIFT 8
> +#define ECR_REC_MASK (0x7f << ECR_REC_SHIFT)
> +#define ECR_TEC_SHIFT 0
> +#define ECR_TEC_MASK 0xff
> +
> +/* Protocol Status Register(PSR) */
> +#define PSR_BO BIT(7)
> +#define PSR_EW BIT(6)
> +#define PSR_EP BIT(5)
> +#define PSR_LEC_MASK 0x7
> +
> /* Interrupt Register(IR) */
> #define IR_ALL_INT 0xffffffff
> #define IR_STE BIT(31)
> @@ -131,10 +156,11 @@ enum m_can_reg {
> #define IR_RF0F BIT(2)
> #define IR_RF0W BIT(1)
> #define IR_RF0N BIT(0)
> -#define IR_ERR_ALL (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE | \
> - IR_WDI | IR_BO | IR_EW | IR_EP | IR_ELO | IR_BEU | \
> - IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \
> - IR_RF0L)
> +#define IR_ERR_STATE (IR_BO | IR_EW | IR_EP)
> +#define IR_ERR_BUS (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE | \
> + IR_WDI | IR_ELO | IR_BEU | IR_BEC | IR_TOO | IR_MRAF | \
> + IR_TSW | IR_TEFL | IR_RF1L | IR_RF0L)
> +#define IR_ERR_ALL (IR_ERR_STATE | IR_ERR_BUS)
>
> /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
> #define RXFC_FWM_OFF 24
> @@ -320,12 +346,175 @@ static int m_can_do_rx_poll(struct net_device *dev, int quota)
> return num_rx_pkts;
> }
>
> +static int m_can_handle_lost_msg(struct net_device *dev)
> +{
> + struct net_device_stats *stats = &dev->stats;
> + struct sk_buff *skb;
> + struct can_frame *frame;
> +
> + netdev_err(dev, "msg lost in rxf0\n");
> +
> + skb = alloc_can_err_skb(dev, &frame);
> + if (unlikely(!skb))
> + return 0;
Please rearrange this function differently, so that the stats are
updated, even if alloc_can_err_skb() fails.
> +
> + frame->can_id |= CAN_ERR_CRTL;
> + frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
> + stats->rx_errors++;
> + stats->rx_over_errors++;
> +
> + netif_receive_skb(skb);
> +
> + return 1;
> +}
> +
> +static int m_can_handle_bus_err(struct net_device *dev,
> + enum m_can_lec_type lec_type)
> +{
> + struct m_can_priv *priv = netdev_priv(dev);
> + struct net_device_stats *stats = &dev->stats;
> + struct can_frame *cf;
> + struct sk_buff *skb;
> +
> + /* early exit if no lec update */
> + if (lec_type == LEC_UNUSED)
> + return 0;
> +
> + /* propagate the error condition to the CAN stack */
> + skb = alloc_can_err_skb(dev, &cf);
> + if (unlikely(!skb))
> + return 0;
same here
> +
> + /*
> + * check for 'last error code' which tells us the
> + * type of the last error to occur on the CAN bus
> + */
> + priv->can.can_stats.bus_error++;
> + stats->rx_errors++;
> + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
> + cf->data[2] |= CAN_ERR_PROT_UNSPEC;
> +
> + switch (lec_type) {
> + case LEC_STUFF_ERROR:
> + netdev_dbg(dev, "stuff error\n");
> + cf->data[2] |= CAN_ERR_PROT_STUFF;
> + break;
> + case LEC_FORM_ERROR:
> + netdev_dbg(dev, "form error\n");
> + cf->data[2] |= CAN_ERR_PROT_FORM;
> + break;
> + case LEC_ACK_ERROR:
> + netdev_dbg(dev, "ack error\n");
> + cf->data[3] |= (CAN_ERR_PROT_LOC_ACK |
> + CAN_ERR_PROT_LOC_ACK_DEL);
> + break;
> + case LEC_BIT1_ERROR:
> + netdev_dbg(dev, "bit1 error\n");
> + cf->data[2] |= CAN_ERR_PROT_BIT1;
> + break;
> + case LEC_BIT0_ERROR:
> + netdev_dbg(dev, "bit0 error\n");
> + cf->data[2] |= CAN_ERR_PROT_BIT0;
> + break;
> + case LEC_CRC_ERROR:
> + netdev_dbg(dev, "CRC error\n");
> + cf->data[3] |= (CAN_ERR_PROT_LOC_CRC_SEQ |
> + CAN_ERR_PROT_LOC_CRC_DEL);
> + break;
> + default:
> + break;
> + }
> +
> + netif_receive_skb(skb);
> + stats->rx_packets++;
> + stats->rx_bytes += cf->can_dlc;
> +
> + return 1;
> +}
> +
> +static int m_can_get_berr_counter(const struct net_device *dev,
> + struct can_berr_counter *bec)
> +{
> + struct m_can_priv *priv = netdev_priv(dev);
> + unsigned int ecr;
This function might be called, even if the interface is down. You might
have to enable the clock(s) here.
> + ecr = m_can_read(priv, M_CAN_ECR);
> + bec->rxerr = (ecr & ECR_REC_MASK) >> ECR_REC_SHIFT;
> + bec->txerr = ecr & ECR_TEC_MASK;
> +
> + return 0;
> +}
> +
> +static int m_can_handle_state_change(struct net_device *dev,
> + enum can_state new_state)
> +{
> + struct m_can_priv *priv = netdev_priv(dev);
> + struct net_device_stats *stats = &dev->stats;
> + struct can_frame *cf;
> + struct sk_buff *skb;
> + struct can_berr_counter bec;
> + unsigned int ecr;
> +
> + /* propagate the error condition to the CAN stack */
> + skb = alloc_can_err_skb(dev, &cf);
> + if (unlikely(!skb))
> + return 0;
Please rearrange the function, so that the stats and more important
bus-off are handled correctly, even if this fails.
> +
> + m_can_get_berr_counter(dev, &bec);
> +
> + switch (new_state) {
> + case CAN_STATE_ERROR_ACTIVE:
> + /* error warning state */
> + priv->can.can_stats.error_warning++;
> + priv->can.state = CAN_STATE_ERROR_WARNING;
> + cf->can_id |= CAN_ERR_CRTL;
> + cf->data[1] = (bec.txerr > bec.rxerr) ?
> + CAN_ERR_CRTL_TX_WARNING :
> + CAN_ERR_CRTL_RX_WARNING;
> + cf->data[6] = bec.txerr;
> + cf->data[7] = bec.rxerr;
> + break;
> + case CAN_STATE_ERROR_PASSIVE:
> + /* error passive state */
> + priv->can.can_stats.error_passive++;
> + priv->can.state = CAN_STATE_ERROR_PASSIVE;
> + cf->can_id |= CAN_ERR_CRTL;
> + ecr = m_can_read(priv, M_CAN_ECR);
> + if (ecr & ECR_RP)
> + cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
> + if (bec.txerr > 127)
> + cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
> + cf->data[6] = bec.txerr;
> + cf->data[7] = bec.rxerr;
> + break;
> + case CAN_STATE_BUS_OFF:
> + /* bus-off state */
> + priv->can.state = CAN_STATE_BUS_OFF;
> + cf->can_id |= CAN_ERR_BUSOFF;
> + /*
> + * disable all interrupts in bus-off mode to ensure that
> + * the CPU is not hogged down
> + */
> + m_can_enable_all_interrupts(priv, false);
> + can_bus_off(dev);
> + break;
> + default:
> + break;
> + }
> +
> + netif_receive_skb(skb);
> + stats->rx_packets++;
> + stats->rx_bytes += cf->can_dlc;
don't acces "cf" after netif_receive_sb();
> +
> + return 1;
> +}
> +
> static int m_can_poll(struct napi_struct *napi, int quota)
> {
> struct net_device *dev = napi->dev;
> struct m_can_priv *priv = netdev_priv(dev);
> u32 work_done = 0;
> - u32 irqstatus;
> + u32 irqstatus, psr;
>
> irqstatus = m_can_read(priv, M_CAN_IR);
> if (irqstatus)
> @@ -337,6 +526,48 @@ static int m_can_poll(struct napi_struct *napi, int quota)
> if (!irqstatus)
> goto end;
>
> + psr = m_can_read(priv, M_CAN_PSR);
> + if (irqstatus & IR_ERR_STATE) {
> + if ((psr & PSR_EW) &&
> + (priv->can.state != CAN_STATE_ERROR_WARNING)) {
> + netdev_dbg(dev, "entered error warning state\n");
> + work_done += m_can_handle_state_change(dev,
> + CAN_STATE_ERROR_WARNING);
> + }
> +
> + if ((psr & PSR_EP) &&
> + (priv->can.state != CAN_STATE_ERROR_PASSIVE)) {
> + netdev_dbg(dev, "entered error warning state\n");
> + work_done += m_can_handle_state_change(dev,
> + CAN_STATE_ERROR_PASSIVE);
> + }
> +
> + if ((psr & PSR_BO) &&
> + (priv->can.state != CAN_STATE_BUS_OFF)) {
> + netdev_dbg(dev, "entered error warning state\n");
> + work_done += m_can_handle_state_change(dev,
> + CAN_STATE_BUS_OFF);
> + }
You might want to push this into a seperate function.
> + }
> +
> + if (irqstatus & IR_ERR_BUS) {
> + if (irqstatus & IR_RF0L)
> + work_done += m_can_handle_lost_msg(dev);
> +
> + /* handle lec errors on the bus */
> + if (psr & LEC_UNUSED)
> + work_done += m_can_handle_bus_err(dev,
> + psr & LEC_UNUSED);
> +
> + /* other unproccessed error interrupts */
> + if (irqstatus & IR_WDI)
> + netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
> + if (irqstatus & IR_TOO)
> + netdev_err(dev, "Timeout reached\n");
> + if (irqstatus & IR_MRAF)
> + netdev_err(dev, "Message RAM access failure occurred\n");
same here
> + }
> +
> if (irqstatus & IR_RF0N)
> /* handle events corresponding to receive message objects */
> work_done += m_can_do_rx_poll(dev, (quota - work_done));
> @@ -369,31 +600,18 @@ static irqreturn_t m_can_isr(int irq, void *dev_id)
> if (ir & IR_ALL_INT)
> m_can_write(priv, M_CAN_IR, ir);
>
> - if (ir & IR_ERR_ALL) {
> - netdev_dbg(dev, "bus error\n");
> - /* TODO: handle bus error */
> - }
> -
> - /* save irqstatus for later using */
> - priv->irqstatus = ir;
> -
> /*
> * schedule NAPI in case of
> * - rx IRQ
> - * - state change IRQ(TODO)
> - * - bus error IRQ and bus error reporting (TODO)
> + * - state change IRQ
> + * - bus error IRQ and bus error reporting
> */
> - if (ir & IR_RF0N) {
> + if ((ir & IR_RF0N) || (ir & IR_ERR_ALL)) {
> + priv->irqstatus = ir;
> m_can_enable_all_interrupts(priv, false);
> napi_schedule(&priv->napi);
> }
>
> - /* FIFO overflow */
> - if (ir & IR_RF0L) {
> - dev->stats.rx_over_errors++;
> - dev->stats.rx_errors++;
> - }
> -
> /* transmission complete interrupt */
> if (ir & IR_TC) {
> netdev_dbg(dev, "tx complete\n");
> @@ -446,7 +664,6 @@ static int m_can_set_bittiming(struct net_device *dev)
> * - setup bittiming
> * - TODO:
> * 1) other working modes support like monitor, loopback...
> - * 2) lec error status report enable
> */
> static void m_can_chip_config(struct net_device *dev)
> {
> @@ -515,14 +732,6 @@ static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
> return 0;
> }
>
> -static int m_can_get_berr_counter(const struct net_device *dev,
> - struct can_berr_counter *bec)
> -{
> - /* TODO */
> -
> - return 0;
> -}
> -
> static void free_m_can_dev(struct net_device *dev)
> {
> free_candev(dev);
>
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
Attachment:
signature.asc
Description: OpenPGP digital signature
