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path: root/drivers/net/can/c_can/c_can.c
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Diffstat (limited to 'drivers/net/can/c_can/c_can.c')
-rw-r--r--drivers/net/can/c_can/c_can.c660
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