diff options
Diffstat (limited to 'drivers/net/can/c_can/c_can.c')
| -rw-r--r-- | drivers/net/can/c_can/c_can.c | 660 |
1 files changed, 306 insertions, 354 deletions
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index a5c8dcfa8357..a2ca820b5373 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -60,6 +60,8 @@ #define CONTROL_IE BIT(1) #define CONTROL_INIT BIT(0) +#define CONTROL_IRQMSK (CONTROL_EIE | CONTROL_IE | CONTROL_SIE) + /* test register */ #define TEST_RX BIT(7) #define TEST_TX1 BIT(6) @@ -108,11 +110,14 @@ #define IF_COMM_CONTROL BIT(4) #define IF_COMM_CLR_INT_PND BIT(3) #define IF_COMM_TXRQST BIT(2) +#define IF_COMM_CLR_NEWDAT IF_COMM_TXRQST #define IF_COMM_DATAA BIT(1) #define IF_COMM_DATAB BIT(0) -#define IF_COMM_ALL (IF_COMM_MASK | IF_COMM_ARB | \ - IF_COMM_CONTROL | IF_COMM_TXRQST | \ - IF_COMM_DATAA | IF_COMM_DATAB) + +/* TX buffer setup */ +#define IF_COMM_TX (IF_COMM_ARB | IF_COMM_CONTROL | \ + IF_COMM_TXRQST | \ + IF_COMM_DATAA | IF_COMM_DATAB) /* For the low buffers we clear the interrupt bit, but keep newdat */ #define IF_COMM_RCV_LOW (IF_COMM_MASK | IF_COMM_ARB | \ @@ -120,12 +125,19 @@ IF_COMM_DATAA | IF_COMM_DATAB) /* For the high buffers we clear the interrupt bit and newdat */ -#define IF_COMM_RCV_HIGH (IF_COMM_RCV_LOW | IF_COMM_TXRQST) +#define IF_COMM_RCV_HIGH (IF_COMM_RCV_LOW | IF_COMM_CLR_NEWDAT) + + +/* Receive setup of message objects */ +#define IF_COMM_RCV_SETUP (IF_COMM_MASK | IF_COMM_ARB | IF_COMM_CONTROL) + +/* Invalidation of message objects */ +#define IF_COMM_INVAL (IF_COMM_ARB | IF_COMM_CONTROL) /* IFx arbitration */ -#define IF_ARB_MSGVAL BIT(15) -#define IF_ARB_MSGXTD BIT(14) -#define IF_ARB_TRANSMIT BIT(13) +#define IF_ARB_MSGVAL BIT(31) +#define IF_ARB_MSGXTD BIT(30) +#define IF_ARB_TRANSMIT BIT(29) /* IFx message control */ #define IF_MCONT_NEWDAT BIT(15) @@ -139,19 +151,17 @@ #define IF_MCONT_EOB BIT(7) #define IF_MCONT_DLC_MASK 0xf +#define IF_MCONT_RCV (IF_MCONT_RXIE | IF_MCONT_UMASK) +#define IF_MCONT_RCV_EOB (IF_MCONT_RCV | IF_MCONT_EOB) + +#define IF_MCONT_TX (IF_MCONT_TXIE | IF_MCONT_EOB) + /* * Use IF1 for RX and IF2 for TX */ #define IF_RX 0 #define IF_TX 1 -/* status interrupt */ -#define STATUS_INTERRUPT 0x8000 - -/* global interrupt masks */ -#define ENABLE_ALL_INTERRUPTS 1 -#define DISABLE_ALL_INTERRUPTS 0 - /* minimum timeout for checking BUSY status */ #define MIN_TIMEOUT_VALUE 6 @@ -171,6 +181,7 @@ enum c_can_lec_type { LEC_BIT0_ERROR, LEC_CRC_ERROR, LEC_UNUSED, + LEC_MASK = LEC_UNUSED, }; /* @@ -226,143 +237,115 @@ static inline void c_can_reset_ram(const struct c_can_priv *priv, bool enable) priv->raminit(priv, enable); } -static inline int get_tx_next_msg_obj(const struct c_can_priv *priv) +static void c_can_irq_control(struct c_can_priv *priv, bool enable) { - 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_enable_all_interrupts(struct c_can_priv *priv, - int enable) -{ - unsigned int cntrl_save = priv->read_reg(priv, - C_CAN_CTRL_REG); + u32 ctrl = priv->read_reg(priv, C_CAN_CTRL_REG) & ~CONTROL_IRQMSK; if (enable) - cntrl_save |= (CONTROL_SIE | CONTROL_EIE | CONTROL_IE); - else - cntrl_save &= ~(CONTROL_EIE | CONTROL_IE | CONTROL_SIE); + ctrl |= CONTROL_IRQMSK; - priv->write_reg(priv, C_CAN_CTRL_REG, cntrl_save); + priv->write_reg(priv, C_CAN_CTRL_REG, ctrl); } -static inline int c_can_msg_obj_is_busy(struct c_can_priv *priv, int iface) +static void c_can_obj_update(struct net_device *dev, int iface, u32 cmd, u32 obj) { - int count = MIN_TIMEOUT_VALUE; + struct c_can_priv *priv = netdev_priv(dev); + int cnt, reg = C_CAN_IFACE(COMREQ_REG, iface); + + priv->write_reg(priv, reg + 1, cmd); + priv->write_reg(priv, reg, obj); - while (count && priv->read_reg(priv, - C_CAN_IFACE(COMREQ_REG, iface)) & - IF_COMR_BUSY) { - count--; + for (cnt = MIN_TIMEOUT_VALUE; cnt; cnt--) { + if (!(priv->read_reg(priv, reg) & IF_COMR_BUSY)) + return; udelay(1); } + netdev_err(dev, "Updating object timed out\n"); - if (!count) - return 1; +} - return 0; +static inline void c_can_object_get(struct net_device *dev, int iface, + u32 obj, u32 cmd) +{ + c_can_obj_update(dev, iface, cmd, obj); } -static inline void c_can_object_get(struct net_device *dev, - int iface, int objno, int mask) +static inline void c_can_object_put(struct net_device *dev, int iface, + u32 obj, u32 cmd) { - struct c_can_priv *priv = netdev_priv(dev); + c_can_obj_update(dev, iface, cmd | IF_COMM_WR, obj); +} - /* - * As per specs, after writting the message object number in the - * IF command request register the transfer b/w interface - * register and message RAM must be complete in 6 CAN-CLK - * period. - */ - priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface), - IFX_WRITE_LOW_16BIT(mask)); - priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface), - IFX_WRITE_LOW_16BIT(objno)); +/* + * Note: According to documentation clearing TXIE while MSGVAL is set + * is not allowed, but works nicely on C/DCAN. And that lowers the I/O + * load significantly. + */ +static void c_can_inval_tx_object(struct net_device *dev, int iface, int obj) +{ + struct c_can_priv *priv = netdev_priv(dev); - if (c_can_msg_obj_is_busy(priv, iface)) - netdev_err(dev, "timed out in object get\n"); + priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), 0); + c_can_object_put(dev, iface, obj, IF_COMM_INVAL); } -static inline void c_can_object_put(struct net_device *dev, - int iface, int objno, int mask) +static void c_can_inval_msg_object(struct net_device *dev, int iface, int obj) { struct c_can_priv *priv = netdev_priv(dev); - /* - * As per specs, after writting the message object number in the - * IF command request register the transfer b/w interface - * register and message RAM must be complete in 6 CAN-CLK - * period. - */ - priv->write_reg(priv, C_CAN_IFACE(COMMSK_REG, iface), - (IF_COMM_WR | IFX_WRITE_LOW_16BIT(mask))); - priv->write_reg(priv, C_CAN_IFACE(COMREQ_REG, iface), - IFX_WRITE_LOW_16BIT(objno)); - - if (c_can_msg_obj_is_busy(priv, iface)) - netdev_err(dev, "timed out in object put\n"); + priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), 0); + priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), 0); + c_can_inval_tx_object(dev, iface, obj); } -static void c_can_write_msg_object(struct net_device *dev, - int iface, struct can_frame *frame, int objno) +static void c_can_setup_tx_object(struct net_device *dev, int iface, + struct can_frame *frame, int idx) { - int i; - u16 flags = 0; - unsigned int id; struct c_can_priv *priv = netdev_priv(dev); - - if (!(frame->can_id & CAN_RTR_FLAG)) - flags |= IF_ARB_TRANSMIT; + u16 ctrl = IF_MCONT_TX | frame->can_dlc; + bool rtr = frame->can_id & CAN_RTR_FLAG; + u32 arb = IF_ARB_MSGVAL; + int i; if (frame->can_id & CAN_EFF_FLAG) { - id = frame->can_id & CAN_EFF_MASK; - flags |= IF_ARB_MSGXTD; - } else - id = ((frame->can_id & CAN_SFF_MASK) << 18); + arb |= frame->can_id & CAN_EFF_MASK; + arb |= IF_ARB_MSGXTD; + } else { + arb |= (frame->can_id & CAN_SFF_MASK) << 18; + } + + if (!rtr) + arb |= IF_ARB_TRANSMIT; - flags |= IF_ARB_MSGVAL; + /* + * If we change the DIR bit, we need to invalidate the buffer + * first, i.e. clear the MSGVAL flag in the arbiter. + */ + if (rtr != (bool)test_bit(idx, &priv->tx_dir)) { + u32 obj = idx + C_CAN_MSG_OBJ_TX_FIRST; + + c_can_inval_msg_object(dev, iface, obj); + change_bit(idx, &priv->tx_dir); + } + + priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), arb); + priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), arb >> 16); - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), - IFX_WRITE_LOW_16BIT(id)); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), flags | - IFX_WRITE_HIGH_16BIT(id)); + priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), ctrl); for (i = 0; i < frame->can_dlc; i += 2) { priv->write_reg(priv, C_CAN_IFACE(DATA1_REG, iface) + i / 2, frame->data[i] | (frame->data[i + 1] << 8)); } - - /* enable interrupt for this message object */ - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - IF_MCONT_TXIE | IF_MCONT_TXRQST | IF_MCONT_EOB | - frame->can_dlc); - c_can_object_put(dev, iface, objno, IF_COMM_ALL); } static inline void c_can_activate_all_lower_rx_msg_obj(struct net_device *dev, - int iface, - int ctrl_mask) + int iface) { int i; - struct c_can_priv *priv = netdev_priv(dev); - for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_MSG_RX_LOW_LAST; i++) { - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), - ctrl_mask & ~IF_MCONT_NEWDAT); - c_can_object_put(dev, iface, i, IF_COMM_CONTROL); - } + for (i = C_CAN_MSG_OBJ_RX_FIRST; i <= C_CAN_MSG_RX_LOW_LAST; i++) + c_can_object_get(dev, iface, i, IF_COMM_CLR_NEWDAT); } static int c_can_handle_lost_msg_obj(struct net_device *dev, @@ -377,6 +360,9 @@ static int c_can_handle_lost_msg_obj(struct net_device *dev, priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), ctrl); c_can_object_put(dev, iface, objno, IF_COMM_CONTROL); + stats->rx_errors++; + stats->rx_over_errors++; + /* create an error msg */ skb = alloc_can_err_skb(dev, &frame); if (unlikely(!skb)) @@ -384,22 +370,18 @@ static int c_can_handle_lost_msg_obj(struct net_device *dev, 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 c_can_read_msg_object(struct net_device *dev, int iface, int ctrl) +static int c_can_read_msg_object(struct net_device *dev, int iface, u32 ctrl) { - u16 flags, data; - int i; - unsigned int val; - struct c_can_priv *priv = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; - struct sk_buff *skb; + struct c_can_priv *priv = netdev_priv(dev); struct can_frame *frame; + struct sk_buff *skb; + u32 arb, data; skb = alloc_can_skb(dev, &frame); if (!skb) { @@ -409,115 +391,82 @@ static int c_can_read_msg_object(struct net_device *dev, int iface, int ctrl) frame->can_dlc = get_can_dlc(ctrl & 0x0F); - flags = priv->read_reg(priv, C_CAN_IFACE(ARB2_REG, iface)); - val = priv->read_reg(priv, C_CAN_IFACE(ARB1_REG, iface)) | - (flags << 16); + arb = priv->read_reg(priv, C_CAN_IFACE(ARB1_REG, iface)); + arb |= priv->read_reg(priv, C_CAN_IFACE(ARB2_REG, iface)) << 16; - if (flags & IF_ARB_MSGXTD) - frame->can_id = (val & CAN_EFF_MASK) | CAN_EFF_FLAG; + if (arb & IF_ARB_MSGXTD) + frame->can_id = (arb & CAN_EFF_MASK) | CAN_EFF_FLAG; else - frame->can_id = (val >> 18) & CAN_SFF_MASK; + frame->can_id = (arb >> 18) & CAN_SFF_MASK; - if (flags & IF_ARB_TRANSMIT) + if (arb & IF_ARB_TRANSMIT) { frame->can_id |= CAN_RTR_FLAG; - else { - for (i = 0; i < frame->can_dlc; i += 2) { - data = priv->read_reg(priv, - C_CAN_IFACE(DATA1_REG, iface) + i / 2); + } else { + int i, dreg = C_CAN_IFACE(DATA1_REG, iface); + + for (i = 0; i < frame->can_dlc; i += 2, dreg ++) { + data = priv->read_reg(priv, dreg); frame->data[i] = data; frame->data[i + 1] = data >> 8; } } - netif_receive_skb(skb); - stats->rx_packets++; stats->rx_bytes += frame->can_dlc; + + netif_receive_skb(skb); return 0; } static void c_can_setup_receive_object(struct net_device *dev, int iface, - int objno, unsigned int mask, - unsigned int id, unsigned int mcont) + u32 obj, u32 mask, u32 id, u32 mcont) { struct c_can_priv *priv = netdev_priv(dev); - priv->write_reg(priv, C_CAN_IFACE(MASK1_REG, iface), - IFX_WRITE_LOW_16BIT(mask)); - - /* According to C_CAN documentation, the reserved bit - * in IFx_MASK2 register is fixed 1 - */ - priv->write_reg(priv, C_CAN_IFACE(MASK2_REG, iface), - IFX_WRITE_HIGH_16BIT(mask) | BIT(13)); + mask |= BIT(29); + priv->write_reg(priv, C_CAN_IFACE(MASK1_REG, iface), mask); + priv->write_reg(priv, C_CAN_IFACE(MASK2_REG, iface), mask >> 16); - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), - IFX_WRITE_LOW_16BIT(id)); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), - (IF_ARB_MSGVAL | IFX_WRITE_HIGH_16BIT(id))); + id |= IF_ARB_MSGVAL; + priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), id); + priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), id >> 16); priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), mcont); - c_can_object_put(dev, iface, objno, IF_COMM_ALL & ~IF_COMM_TXRQST); - - netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno, - c_can_read_reg32(priv, C_CAN_MSGVAL1_REG)); -} - -static void c_can_inval_msg_object(struct net_device *dev, int iface, int objno) -{ - struct c_can_priv *priv = netdev_priv(dev); - - priv->write_reg(priv, C_CAN_IFACE(ARB1_REG, iface), 0); - priv->write_reg(priv, C_CAN_IFACE(ARB2_REG, iface), 0); - priv->write_reg(priv, C_CAN_IFACE(MSGCTRL_REG, iface), 0); - - c_can_object_put(dev, iface, objno, IF_COMM_ARB | IF_COMM_CONTROL); - - netdev_dbg(dev, "obj no:%d, msgval:0x%08x\n", objno, - c_can_read_reg32(priv, C_CAN_MSGVAL1_REG)); -} - -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; + c_can_object_put(dev, iface, obj, IF_COMM_RCV_SETUP); } 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, idx); + 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; } @@ -594,11 +543,10 @@ static void c_can_configure_msg_objects(struct net_device *dev) /* setup receive message objects */ for (i = C_CAN_MSG_OBJ_RX_FIRST; i < C_CAN_MSG_OBJ_RX_LAST; i++) - c_can_setup_receive_object(dev, IF_RX, i, 0, 0, - (IF_MCONT_RXIE | IF_MCONT_UMASK) & ~IF_MCONT_EOB); + c_can_setup_receive_object(dev, IF_RX, i, 0, 0, IF_MCONT_RCV); c_can_setup_receive_object(dev, IF_RX, C_CAN_MSG_OBJ_RX_LAST, 0, 0, - IF_MCONT_EOB | IF_MCONT_RXIE | IF_MCONT_UMASK); + IF_MCONT_RCV_EOB); } /* @@ -612,30 +560,22 @@ static int c_can_chip_config(struct net_device *dev) struct c_can_priv *priv = netdev_priv(dev); /* enable automatic retransmission */ - priv->write_reg(priv, C_CAN_CTRL_REG, - CONTROL_ENABLE_AR); + priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_ENABLE_AR); if ((priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) && (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)) { /* loopback + silent mode : useful for hot self-test */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); - priv->write_reg(priv, C_CAN_TEST_REG, - TEST_LBACK | TEST_SILENT); + priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST); + priv->write_reg(priv, C_CAN_TEST_REG, TEST_LBACK | TEST_SILENT); } else if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) { /* loopback mode : useful for self-test function */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); + priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST); priv->write_reg(priv, C_CAN_TEST_REG, TEST_LBACK); } else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) { /* silent mode : bus-monitoring mode */ - priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_EIE | - CONTROL_SIE | CONTROL_IE | CONTROL_TEST); + priv->write_reg(priv, C_CAN_CTRL_REG, CONTROL_TEST); priv->write_reg(priv, C_CAN_TEST_REG, TEST_SILENT); - } else - /* normal mode*/ - priv->write_reg(priv, C_CAN_CTRL_REG, - CONTROL_EIE | CONTROL_SIE | CONTROL_IE); + } /* configure message objects */ c_can_configure_msg_objects(dev); @@ -643,6 +583,11 @@ static int c_can_chip_config(struct net_device *dev) /* 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; + priv->tx_dir = 0; + /* set bittiming params */ return c_can_set_bittiming(dev); } @@ -657,13 +602,11 @@ static int c_can_start(struct net_device *dev) if (err) return err; - priv->can.state = CAN_STATE_ERROR_ACTIVE; - - /* reset tx helper pointers */ - priv->tx_next = priv->tx_echo = 0; + /* Setup the command for new messages */ + priv->comm_rcv_high = priv->type != BOSCH_D_CAN ? + IF_COMM_RCV_LOW : IF_COMM_RCV_HIGH; - /* enable status change, error and module interrupts */ - c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS); + priv->can.state = CAN_STATE_ERROR_ACTIVE; return 0; } @@ -672,15 +615,13 @@ static void c_can_stop(struct net_device *dev) { struct c_can_priv *priv = netdev_priv(dev); - /* disable all interrupts */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); - - /* set the state as STOPPED */ + c_can_irq_control(priv, false); priv->can.state = CAN_STATE_STOPPED; } static int c_can_set_mode(struct net_device *dev, enum can_mode mode) { + struct c_can_priv *priv = netdev_priv(dev); int err; switch (mode) { @@ -689,6 +630,7 @@ static int c_can_set_mode(struct net_device *dev, enum can_mode mode) if (err) return err; netif_wake_queue(dev); + c_can_irq_control(priv, true); break; default: return -EOPNOTSUPP; @@ -724,42 +666,29 @@ static int c_can_get_berr_counter(const struct net_device *dev, 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; - - spin_lock_bh(&priv->xmit_lock); + u32 idx, obj, pkts = 0, bytes = 0, pend, clr; - 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); + clr = pend = priv->read_reg(priv, C_CAN_INTPND2_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_tx_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; @@ -800,18 +729,42 @@ static u32 c_can_adjust_pending(u32 pend) return pend & ~((1 << lasts) - 1); } +static inline void c_can_rx_object_get(struct net_device *dev, + struct c_can_priv *priv, u32 obj) +{ +#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING + if (obj < C_CAN_MSG_RX_LOW_LAST) + c_can_object_get(dev, IF_RX, obj, IF_COMM_RCV_LOW); + else +#endif + c_can_object_get(dev, IF_RX, obj, priv->comm_rcv_high); +} + +static inline void c_can_rx_finalize(struct net_device *dev, + struct c_can_priv *priv, u32 obj) +{ +#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING + if (obj < C_CAN_MSG_RX_LOW_LAST) + priv->rxmasked |= BIT(obj - 1); + else if (obj == C_CAN_MSG_RX_LOW_LAST) { + priv->rxmasked = 0; + /* activate all lower message objects */ + c_can_activate_all_lower_rx_msg_obj(dev, IF_RX); + } +#endif + if (priv->type != BOSCH_D_CAN) + c_can_object_get(dev, IF_RX, obj, IF_COMM_CLR_NEWDAT); +} + static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, u32 pend, int quota) { - u32 pkts = 0, ctrl, obj, mcmd; + u32 pkts = 0, ctrl, obj; while ((obj = ffs(pend)) && quota > 0) { pend &= ~BIT(obj - 1); - mcmd = obj < C_CAN_MSG_RX_LOW_LAST ? - IF_COMM_RCV_LOW : IF_COMM_RCV_HIGH; - - c_can_object_get(dev, IF_RX, obj, mcmd); + c_can_rx_object_get(dev, priv, obj); ctrl = priv->read_reg(priv, C_CAN_IFACE(MSGCTRL_REG, IF_RX)); if (ctrl & IF_MCONT_MSGLST) { @@ -833,9 +786,7 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, /* read the data from the message object */ c_can_read_msg_object(dev, IF_RX, ctrl); - if (obj == C_CAN_MSG_RX_LOW_LAST) - /* activate all lower message objects */ - c_can_activate_all_lower_rx_msg_obj(dev, IF_RX, ctrl); + c_can_rx_finalize(dev, priv, obj); pkts++; quota--; @@ -844,6 +795,16 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, return pkts; } +static inline u32 c_can_get_pending(struct c_can_priv *priv) +{ + u32 pend = priv->read_reg(priv, C_CAN_NEWDAT1_REG); + +#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING + pend &= ~priv->rxmasked; +#endif + return pend; +} + /* * theory of operation: * @@ -853,6 +814,8 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, * has arrived. To work-around this issue, we keep two groups of message * objects whose partitioning is defined by C_CAN_MSG_OBJ_RX_SPLIT. * + * If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = y + * * To ensure in-order frame reception we use the following * approach while re-activating a message object to receive further * frames: @@ -865,6 +828,14 @@ static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv, * - if the current message object number is greater than * C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of * only this message object. + * + * This can cause packet loss! + * + * If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = n + * + * We clear the newdat bit right away. + * + * This can result in packet reordering when the readout is slow. */ static int c_can_do_rx_poll(struct net_device *dev, int quota) { @@ -880,7 +851,7 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) while (quota > 0) { if (!pend) { - pend = priv->read_reg(priv, C_CAN_INTPND1_REG); + pend = c_can_get_pending(priv); if (!pend) break; /* @@ -905,12 +876,6 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) return pkts; } -static inline int c_can_has_and_handle_berr(struct c_can_priv *priv) -{ - return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) && - (priv->current_status & LEC_UNUSED); -} - static int c_can_handle_state_change(struct net_device *dev, enum c_can_bus_error_types error_type) { @@ -922,6 +887,26 @@ static int c_can_handle_state_change(struct net_device *dev, struct sk_buff *skb; struct can_berr_counter bec; + switch (error_type) { + case C_CAN_ERROR_WARNING: + /* error warning state */ + priv->can.can_stats.error_warning++; + priv->can.state = CAN_STATE_ERROR_WARNING; + break; + case C_CAN_ERROR_PASSIVE: + /* error passive state */ + priv->can.can_stats.error_passive++; + priv->can.state = CAN_STATE_ERROR_PASSIVE; + break; + case C_CAN_BUS_OFF: + /* bus-off state */ + priv->can.state = CAN_STATE_BUS_OFF; + can_bus_off(dev); + break; + default: + break; + } + /* propagate the error condition to the CAN stack */ skb = alloc_can_err_skb(dev, &cf); if (unlikely(!skb)) @@ -935,8 +920,6 @@ static int c_can_handle_state_change(struct net_device *dev, switch (error_type) { case C_CAN_ERROR_WARNING: /* 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 : @@ -947,8 +930,6 @@ static int c_can_handle_state_change(struct net_device *dev, break; case C_CAN_ERROR_PASSIVE: /* error passive state */ - priv->can.can_stats.error_passive++; - priv->can.state = CAN_STATE_ERROR_PASSIVE; cf->can_id |= CAN_ERR_CRTL; if (rx_err_passive) cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; @@ -960,22 +941,16 @@ static int c_can_handle_state_change(struct net_device *dev, break; case C_CAN_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 - */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); can_bus_off(dev); break; default: break; } - netif_receive_skb(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; + netif_receive_skb(skb); return 1; } @@ -996,6 +971,13 @@ static int c_can_handle_bus_err(struct net_device *dev, if (lec_type == LEC_UNUSED || lec_type == LEC_NO_ERROR) return 0; + if (!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) + return 0; + + /* common for all type of bus errors */ + priv->can.can_stats.bus_error++; + stats->rx_errors++; + /* propagate the error condition to the CAN stack */ skb = alloc_can_err_skb(dev, &cf); if (unlikely(!skb)) @@ -1005,10 +987,6 @@ static int c_can_handle_bus_err(struct net_device *dev, * check for 'last error code' which tells us the * type of the last error to occur on the CAN bus */ - - /* common for all type of bus errors */ - 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; @@ -1043,95 +1021,64 @@ static int c_can_handle_bus_err(struct net_device *dev, break; } - /* set a `lec` value so that we can check for updates later */ - priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED); - - netif_receive_skb(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; - + netif_receive_skb(skb); return 1; } static int c_can_poll(struct napi_struct *napi, int quota) { - u16 irqstatus; - int lec_type = 0; - int work_done = 0; struct net_device *dev = napi->dev; struct c_can_priv *priv = netdev_priv(dev); + u16 curr, last = priv->last_status; + int work_done = 0; - irqstatus = priv->irqstatus; - if (!irqstatus) - goto end; + priv->last_status = curr = priv->read_reg(priv, C_CAN_STS_REG); + /* Ack status on C_CAN. D_CAN is self clearing */ + if (priv->type != BOSCH_D_CAN) + priv->write_reg(priv, C_CAN_STS_REG, LEC_UNUSED); - /* status events have the highest priority */ - if (irqstatus == STATUS_INTERRUPT) { - priv->current_status = priv->read_reg(priv, - C_CAN_STS_REG); - - /* handle Tx/Rx events */ - if (priv->current_status & STATUS_TXOK) - priv->write_reg(priv, C_CAN_STS_REG, - priv->current_status & ~STATUS_TXOK); - - if (priv->current_status & STATUS_RXOK) - priv->write_reg(priv, C_CAN_STS_REG, - priv->current_status & ~STATUS_RXOK); - - /* handle state changes */ - if ((priv->current_status & STATUS_EWARN) && - (!(priv->last_status & STATUS_EWARN))) { - netdev_dbg(dev, "entered error warning state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_ERROR_WARNING); - } - if ((priv->current_status & STATUS_EPASS) && - (!(priv->last_status & STATUS_EPASS))) { - netdev_dbg(dev, "entered error passive state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_ERROR_PASSIVE); - } - if ((priv->current_status & STATUS_BOFF) && - (!(priv->last_status & STATUS_BOFF))) { - netdev_dbg(dev, "entered bus off state\n"); - work_done += c_can_handle_state_change(dev, - C_CAN_BUS_OFF); - } + /* handle state changes */ + if ((curr & STATUS_EWARN) && (!(last & STATUS_EWARN))) { + netdev_dbg(dev, "entered error warning state\n"); + work_done += c_can_handle_state_change(dev, C_CAN_ERROR_WARNING); + } - /* handle bus recovery events */ - if ((!(priv->current_status & STATUS_BOFF)) && - (priv->last_status & STATUS_BOFF)) { - netdev_dbg(dev, "left bus off state\n"); - priv->can.state = CAN_STATE_ERROR_ACTIVE; - } - if ((!(priv->current_status & STATUS_EPASS)) && - (priv->last_status & STATUS_EPASS)) { - netdev_dbg(dev, "left error passive state\n"); - priv->can.state = CAN_STATE_ERROR_ACTIVE; - } + if ((curr & STATUS_EPASS) && (!(last & STATUS_EPASS))) { + netdev_dbg(dev, "entered error passive state\n"); + work_done += c_can_handle_state_change(dev, C_CAN_ERROR_PASSIVE); + } + + if ((curr & STATUS_BOFF) && (!(last & STATUS_BOFF))) { + netdev_dbg(dev, "entered bus off state\n"); + work_done += c_can_handle_state_change(dev, C_CAN_BUS_OFF); + goto end; + } - priv->last_status = priv->current_status; - - /* handle lec errors on the bus */ - lec_type = c_can_has_and_handle_berr(priv); - if (lec_type) - work_done += c_can_handle_bus_err(dev, lec_type); - } else if ((irqstatus >= C_CAN_MSG_OBJ_RX_FIRST) && - (irqstatus <= C_CAN_MSG_OBJ_RX_LAST)) { - /* handle events corresponding to receive message objects */ - work_done += c_can_do_rx_poll(dev, (quota - work_done)); - } else if ((irqstatus >= C_CAN_MSG_OBJ_TX_FIRST) && - (irqstatus <= C_CAN_MSG_OBJ_TX_LAST)) { - /* handle events corresponding to transmit message objects */ - c_can_do_tx(dev); + /* handle bus recovery events */ + if ((!(curr & STATUS_BOFF)) && (last & STATUS_BOFF)) { + netdev_dbg(dev, "left bus off state\n"); + priv->can.state = CAN_STATE_ERROR_ACTIVE; + } + if ((!(curr & STATUS_EPASS)) && (last & STATUS_EPASS)) { + netdev_dbg(dev, "left error passive state\n"); + priv->can.state = CAN_STATE_ERROR_ACTIVE; } + /* handle lec errors on the bus */ + work_done += c_can_handle_bus_err(dev, curr & LEC_MASK); + + /* Handle Tx/Rx events. We do this unconditionally */ + work_done += c_can_do_rx_poll(dev, (quota - work_done)); + c_can_do_tx(dev); + end: if (work_done < quota) { napi_complete(napi); - /* enable all IRQs */ - c_can_enable_all_interrupts(priv, ENABLE_ALL_INTERRUPTS); + /* enable all IRQs if we are not in bus off state */ + if (priv->can.state != CAN_STATE_BUS_OFF) + c_can_irq_control(priv, true); } return work_done; @@ -1142,12 +1089,11 @@ static irqreturn_t c_can_isr(int irq, void *dev_id) struct net_device *dev = (struct net_device *)dev_id; struct c_can_priv *priv = netdev_priv(dev); - priv->irqstatus = priv->read_reg(priv, C_CAN_INT_REG); - if (!priv->irqstatus) + if (!priv->read_reg(priv, C_CAN_INT_REG)) return IRQ_NONE; /* disable all interrupts and schedule the NAPI */ - c_can_enable_all_interrupts(priv, DISABLE_ALL_INTERRUPTS); + c_can_irq_control(priv, false); napi_schedule(&priv->napi); return IRQ_HANDLED; @@ -1184,6 +1130,8 @@ static int c_can_open(struct net_device *dev) can_led_event(dev, CAN_LED_EVENT_OPEN); napi_enable(&priv->napi); + /* enable status change, error and module interrupts */ + c_can_irq_control(priv, true); netif_start_queue(dev); return 0; @@ -1226,7 +1174,6 @@ struct net_device *alloc_c_can_dev(void) 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; @@ -1281,6 +1228,7 @@ int c_can_power_up(struct net_device *dev) u32 val; unsigned long time_out; struct c_can_priv *priv = netdev_priv(dev); + int ret; if (!(dev->flags & IFF_UP)) return 0; @@ -1307,7 +1255,11 @@ int c_can_power_up(struct net_device *dev) if (time_after(jiffies, time_out)) return -ETIMEDOUT; - return c_can_start(dev); + ret = c_can_start(dev); + if (!ret) + c_can_irq_control(priv, true); + + return ret; } EXPORT_SYMBOL_GPL(c_can_power_up); #endif |