aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/can/xilinx_can.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/can/xilinx_can.c')
-rw-r--r--drivers/net/can/xilinx_can.c512
1 files changed, 368 insertions, 144 deletions
diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 5a24039733ef..045f0845e665 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -2,7 +2,7 @@
*
* Copyright (C) 2012 - 2014 Xilinx, Inc.
* Copyright (C) 2009 PetaLogix. All rights reserved.
- * Copyright (C) 2017 Sandvik Mining and Construction Oy
+ * Copyright (C) 2017 - 2018 Sandvik Mining and Construction Oy
*
* Description:
* This driver is developed for Axi CAN IP and for Zynq CANPS Controller.
@@ -51,16 +51,34 @@ enum xcan_reg {
XCAN_ISR_OFFSET = 0x1C, /* Interrupt status */
XCAN_IER_OFFSET = 0x20, /* Interrupt enable */
XCAN_ICR_OFFSET = 0x24, /* Interrupt clear */
- XCAN_TXFIFO_ID_OFFSET = 0x30,/* TX FIFO ID */
- XCAN_TXFIFO_DLC_OFFSET = 0x34, /* TX FIFO DLC */
- XCAN_TXFIFO_DW1_OFFSET = 0x38, /* TX FIFO Data Word 1 */
- XCAN_TXFIFO_DW2_OFFSET = 0x3C, /* TX FIFO Data Word 2 */
- XCAN_RXFIFO_ID_OFFSET = 0x50, /* RX FIFO ID */
- XCAN_RXFIFO_DLC_OFFSET = 0x54, /* RX FIFO DLC */
- XCAN_RXFIFO_DW1_OFFSET = 0x58, /* RX FIFO Data Word 1 */
- XCAN_RXFIFO_DW2_OFFSET = 0x5C, /* RX FIFO Data Word 2 */
+
+ /* not on CAN FD cores */
+ XCAN_TXFIFO_OFFSET = 0x30, /* TX FIFO base */
+ XCAN_RXFIFO_OFFSET = 0x50, /* RX FIFO base */
+ XCAN_AFR_OFFSET = 0x60, /* Acceptance Filter */
+
+ /* only on CAN FD cores */
+ XCAN_TRR_OFFSET = 0x0090, /* TX Buffer Ready Request */
+ XCAN_AFR_EXT_OFFSET = 0x00E0, /* Acceptance Filter */
+ XCAN_FSR_OFFSET = 0x00E8, /* RX FIFO Status */
+ XCAN_TXMSG_BASE_OFFSET = 0x0100, /* TX Message Space */
+ XCAN_RXMSG_BASE_OFFSET = 0x1100, /* RX Message Space */
};
+#define XCAN_FRAME_ID_OFFSET(frame_base) ((frame_base) + 0x00)
+#define XCAN_FRAME_DLC_OFFSET(frame_base) ((frame_base) + 0x04)
+#define XCAN_FRAME_DW1_OFFSET(frame_base) ((frame_base) + 0x08)
+#define XCAN_FRAME_DW2_OFFSET(frame_base) ((frame_base) + 0x0C)
+
+#define XCAN_CANFD_FRAME_SIZE 0x48
+#define XCAN_TXMSG_FRAME_OFFSET(n) (XCAN_TXMSG_BASE_OFFSET + \
+ XCAN_CANFD_FRAME_SIZE * (n))
+#define XCAN_RXMSG_FRAME_OFFSET(n) (XCAN_RXMSG_BASE_OFFSET + \
+ XCAN_CANFD_FRAME_SIZE * (n))
+
+/* the single TX mailbox used by this driver on CAN FD HW */
+#define XCAN_TX_MAILBOX_IDX 0
+
/* CAN register bit masks - XCAN_<REG>_<BIT>_MASK */
#define XCAN_SRR_CEN_MASK 0x00000002 /* CAN enable */
#define XCAN_SRR_RESET_MASK 0x00000001 /* Soft Reset the CAN core */
@@ -70,6 +88,9 @@ enum xcan_reg {
#define XCAN_BTR_SJW_MASK 0x00000180 /* Synchronous jump width */
#define XCAN_BTR_TS2_MASK 0x00000070 /* Time segment 2 */
#define XCAN_BTR_TS1_MASK 0x0000000F /* Time segment 1 */
+#define XCAN_BTR_SJW_MASK_CANFD 0x000F0000 /* Synchronous jump width */
+#define XCAN_BTR_TS2_MASK_CANFD 0x00000F00 /* Time segment 2 */
+#define XCAN_BTR_TS1_MASK_CANFD 0x0000003F /* Time segment 1 */
#define XCAN_ECR_REC_MASK 0x0000FF00 /* Receive error counter */
#define XCAN_ECR_TEC_MASK 0x000000FF /* Transmit error counter */
#define XCAN_ESR_ACKER_MASK 0x00000010 /* ACK error */
@@ -83,6 +104,7 @@ enum xcan_reg {
#define XCAN_SR_NORMAL_MASK 0x00000008 /* Normal mode */
#define XCAN_SR_LBACK_MASK 0x00000002 /* Loop back mode */
#define XCAN_SR_CONFIG_MASK 0x00000001 /* Configuration mode */
+#define XCAN_IXR_RXMNF_MASK 0x00020000 /* RX match not finished */
#define XCAN_IXR_TXFEMP_MASK 0x00004000 /* TX FIFO Empty */
#define XCAN_IXR_WKUP_MASK 0x00000800 /* Wake up interrupt */
#define XCAN_IXR_SLP_MASK 0x00000400 /* Sleep interrupt */
@@ -100,15 +122,15 @@ enum xcan_reg {
#define XCAN_IDR_ID2_MASK 0x0007FFFE /* Extended message ident */
#define XCAN_IDR_RTR_MASK 0x00000001 /* Remote TX request */
#define XCAN_DLCR_DLC_MASK 0xF0000000 /* Data length code */
-
-#define XCAN_INTR_ALL (XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
- XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
- XCAN_IXR_RXNEMP_MASK | XCAN_IXR_ERROR_MASK | \
- XCAN_IXR_RXOFLW_MASK | XCAN_IXR_ARBLST_MASK)
+#define XCAN_FSR_FL_MASK 0x00003F00 /* RX Fill Level */
+#define XCAN_FSR_IRI_MASK 0x00000080 /* RX Increment Read Index */
+#define XCAN_FSR_RI_MASK 0x0000001F /* RX Read Index */
/* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
#define XCAN_BTR_SJW_SHIFT 7 /* Synchronous jump width */
#define XCAN_BTR_TS2_SHIFT 4 /* Time segment 2 */
+#define XCAN_BTR_SJW_SHIFT_CANFD 16 /* Synchronous jump width */
+#define XCAN_BTR_TS2_SHIFT_CANFD 8 /* Time segment 2 */
#define XCAN_IDR_ID1_SHIFT 21 /* Standard Messg Identifier */
#define XCAN_IDR_ID2_SHIFT 1 /* Extended Message Identifier */
#define XCAN_DLCR_DLC_SHIFT 28 /* Data length code */
@@ -118,6 +140,27 @@ enum xcan_reg {
#define XCAN_FRAME_MAX_DATA_LEN 8
#define XCAN_TIMEOUT (1 * HZ)
+/* TX-FIFO-empty interrupt available */
+#define XCAN_FLAG_TXFEMP 0x0001
+/* RX Match Not Finished interrupt available */
+#define XCAN_FLAG_RXMNF 0x0002
+/* Extended acceptance filters with control at 0xE0 */
+#define XCAN_FLAG_EXT_FILTERS 0x0004
+/* TX mailboxes instead of TX FIFO */
+#define XCAN_FLAG_TX_MAILBOXES 0x0008
+/* RX FIFO with each buffer in separate registers at 0x1100
+ * instead of the regular FIFO at 0x50
+ */
+#define XCAN_FLAG_RX_FIFO_MULTI 0x0010
+
+struct xcan_devtype_data {
+ unsigned int flags;
+ const struct can_bittiming_const *bittiming_const;
+ const char *bus_clk_name;
+ unsigned int btr_ts2_shift;
+ unsigned int btr_sjw_shift;
+};
+
/**
* struct xcan_priv - This definition define CAN driver instance
* @can: CAN private data structure.
@@ -133,6 +176,7 @@ enum xcan_reg {
* @irq_flags: For request_irq()
* @bus_clk: Pointer to struct clk
* @can_clk: Pointer to struct clk
+ * @devtype: Device type specific constants
*/
struct xcan_priv {
struct can_priv can;
@@ -149,6 +193,7 @@ struct xcan_priv {
unsigned long irq_flags;
struct clk *bus_clk;
struct clk *can_clk;
+ struct xcan_devtype_data devtype;
};
/* CAN Bittiming constants as per Xilinx CAN specs */
@@ -164,9 +209,16 @@ static const struct can_bittiming_const xcan_bittiming_const = {
.brp_inc = 1,
};
-#define XCAN_CAP_WATERMARK 0x0001
-struct xcan_devtype_data {
- unsigned int caps;
+static const struct can_bittiming_const xcan_bittiming_const_canfd = {
+ .name = DRIVER_NAME,
+ .tseg1_min = 1,
+ .tseg1_max = 64,
+ .tseg2_min = 1,
+ .tseg2_max = 16,
+ .sjw_max = 16,
+ .brp_min = 1,
+ .brp_max = 256,
+ .brp_inc = 1,
};
/**
@@ -224,6 +276,23 @@ static u32 xcan_read_reg_be(const struct xcan_priv *priv, enum xcan_reg reg)
}
/**
+ * xcan_rx_int_mask - Get the mask for the receive interrupt
+ * @priv: Driver private data structure
+ *
+ * Return: The receive interrupt mask used by the driver on this HW
+ */
+static u32 xcan_rx_int_mask(const struct xcan_priv *priv)
+{
+ /* RXNEMP is better suited for our use case as it cannot be cleared
+ * while the FIFO is non-empty, but CAN FD HW does not have it
+ */
+ if (priv->devtype.flags & XCAN_FLAG_RX_FIFO_MULTI)
+ return XCAN_IXR_RXOK_MASK;
+ else
+ return XCAN_IXR_RXNEMP_MASK;
+}
+
+/**
* set_reset_mode - Resets the CAN device mode
* @ndev: Pointer to net_device structure
*
@@ -287,10 +356,10 @@ static int xcan_set_bittiming(struct net_device *ndev)
btr1 = (bt->prop_seg + bt->phase_seg1 - 1);
/* Setting Time Segment 2 in BTR Register */
- btr1 |= (bt->phase_seg2 - 1) << XCAN_BTR_TS2_SHIFT;
+ btr1 |= (bt->phase_seg2 - 1) << priv->devtype.btr_ts2_shift;
/* Setting Synchronous jump width in BTR Register */
- btr1 |= (bt->sjw - 1) << XCAN_BTR_SJW_SHIFT;
+ btr1 |= (bt->sjw - 1) << priv->devtype.btr_sjw_shift;
priv->write_reg(priv, XCAN_BRPR_OFFSET, btr0);
priv->write_reg(priv, XCAN_BTR_OFFSET, btr1);
@@ -318,6 +387,7 @@ static int xcan_chip_start(struct net_device *ndev)
u32 reg_msr, reg_sr_mask;
int err;
unsigned long timeout;
+ u32 ier;
/* Check if it is in reset mode */
err = set_reset_mode(ndev);
@@ -329,7 +399,15 @@ static int xcan_chip_start(struct net_device *ndev)
return err;
/* Enable interrupts */
- priv->write_reg(priv, XCAN_IER_OFFSET, XCAN_INTR_ALL);
+ ier = XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |
+ XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK |
+ XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
+ XCAN_IXR_ARBLST_MASK | xcan_rx_int_mask(priv);
+
+ if (priv->devtype.flags & XCAN_FLAG_RXMNF)
+ ier |= XCAN_IXR_RXMNF_MASK;
+
+ priv->write_reg(priv, XCAN_IER_OFFSET, ier);
/* Check whether it is loopback mode or normal mode */
if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
@@ -340,6 +418,12 @@ static int xcan_chip_start(struct net_device *ndev)
reg_sr_mask = XCAN_SR_NORMAL_MASK;
}
+ /* enable the first extended filter, if any, as cores with extended
+ * filtering default to non-receipt if all filters are disabled
+ */
+ if (priv->devtype.flags & XCAN_FLAG_EXT_FILTERS)
+ priv->write_reg(priv, XCAN_AFR_EXT_OFFSET, 0x00000001);
+
priv->write_reg(priv, XCAN_MSR_OFFSET, reg_msr);
priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK);
@@ -390,34 +474,15 @@ static int xcan_do_set_mode(struct net_device *ndev, enum can_mode mode)
}
/**
- * xcan_start_xmit - Starts the transmission
- * @skb: sk_buff pointer that contains data to be Txed
- * @ndev: Pointer to net_device structure
- *
- * This function is invoked from upper layers to initiate transmission. This
- * function uses the next available free txbuff and populates their fields to
- * start the transmission.
- *
- * Return: 0 on success and failure value on error
+ * xcan_write_frame - Write a frame to HW
+ * @skb: sk_buff pointer that contains data to be Txed
+ * @frame_offset: Register offset to write the frame to
*/
-static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+static void xcan_write_frame(struct xcan_priv *priv, struct sk_buff *skb,
+ int frame_offset)
{
- struct xcan_priv *priv = netdev_priv(ndev);
- struct net_device_stats *stats = &ndev->stats;
- struct can_frame *cf = (struct can_frame *)skb->data;
u32 id, dlc, data[2] = {0, 0};
- unsigned long flags;
-
- if (can_dropped_invalid_skb(ndev, skb))
- return NETDEV_TX_OK;
-
- /* Check if the TX buffer is full */
- if (unlikely(priv->read_reg(priv, XCAN_SR_OFFSET) &
- XCAN_SR_TXFLL_MASK)) {
- netif_stop_queue(ndev);
- netdev_err(ndev, "BUG!, TX FIFO full when queue awake!\n");
- return NETDEV_TX_BUSY;
- }
+ struct can_frame *cf = (struct can_frame *)skb->data;
/* Watch carefully on the bit sequence */
if (cf->can_id & CAN_EFF_FLAG) {
@@ -453,24 +518,44 @@ static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
if (cf->can_dlc > 4)
data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
+ priv->write_reg(priv, XCAN_FRAME_ID_OFFSET(frame_offset), id);
+ /* If the CAN frame is RTR frame this write triggers transmission
+ * (not on CAN FD)
+ */
+ priv->write_reg(priv, XCAN_FRAME_DLC_OFFSET(frame_offset), dlc);
+ if (!(cf->can_id & CAN_RTR_FLAG)) {
+ priv->write_reg(priv, XCAN_FRAME_DW1_OFFSET(frame_offset),
+ data[0]);
+ /* If the CAN frame is Standard/Extended frame this
+ * write triggers transmission (not on CAN FD)
+ */
+ priv->write_reg(priv, XCAN_FRAME_DW2_OFFSET(frame_offset),
+ data[1]);
+ }
+}
+
+/**
+ * xcan_start_xmit_fifo - Starts the transmission (FIFO mode)
+ *
+ * Return: 0 on success, -ENOSPC if FIFO is full.
+ */
+static int xcan_start_xmit_fifo(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct xcan_priv *priv = netdev_priv(ndev);
+ unsigned long flags;
+
+ /* Check if the TX buffer is full */
+ if (unlikely(priv->read_reg(priv, XCAN_SR_OFFSET) &
+ XCAN_SR_TXFLL_MASK))
+ return -ENOSPC;
+
can_put_echo_skb(skb, ndev, priv->tx_head % priv->tx_max);
spin_lock_irqsave(&priv->tx_lock, flags);
priv->tx_head++;
- /* Write the Frame to Xilinx CAN TX FIFO */
- priv->write_reg(priv, XCAN_TXFIFO_ID_OFFSET, id);
- /* If the CAN frame is RTR frame this write triggers tranmission */
- priv->write_reg(priv, XCAN_TXFIFO_DLC_OFFSET, dlc);
- if (!(cf->can_id & CAN_RTR_FLAG)) {
- priv->write_reg(priv, XCAN_TXFIFO_DW1_OFFSET, data[0]);
- /* If the CAN frame is Standard/Extended frame this
- * write triggers tranmission
- */
- priv->write_reg(priv, XCAN_TXFIFO_DW2_OFFSET, data[1]);
- stats->tx_bytes += cf->can_dlc;
- }
+ xcan_write_frame(priv, skb, XCAN_TXFIFO_OFFSET);
/* Clear TX-FIFO-empty interrupt for xcan_tx_interrupt() */
if (priv->tx_max > 1)
@@ -482,6 +567,70 @@ static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
spin_unlock_irqrestore(&priv->tx_lock, flags);
+ return 0;
+}
+
+/**
+ * xcan_start_xmit_mailbox - Starts the transmission (mailbox mode)
+ *
+ * Return: 0 on success, -ENOSPC if there is no space
+ */
+static int xcan_start_xmit_mailbox(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct xcan_priv *priv = netdev_priv(ndev);
+ unsigned long flags;
+
+ if (unlikely(priv->read_reg(priv, XCAN_TRR_OFFSET) &
+ BIT(XCAN_TX_MAILBOX_IDX)))
+ return -ENOSPC;
+
+ can_put_echo_skb(skb, ndev, 0);
+
+ spin_lock_irqsave(&priv->tx_lock, flags);
+
+ priv->tx_head++;
+
+ xcan_write_frame(priv, skb,
+ XCAN_TXMSG_FRAME_OFFSET(XCAN_TX_MAILBOX_IDX));
+
+ /* Mark buffer as ready for transmit */
+ priv->write_reg(priv, XCAN_TRR_OFFSET, BIT(XCAN_TX_MAILBOX_IDX));
+
+ netif_stop_queue(ndev);
+
+ spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+ return 0;
+}
+
+/**
+ * xcan_start_xmit - Starts the transmission
+ * @skb: sk_buff pointer that contains data to be Txed
+ * @ndev: Pointer to net_device structure
+ *
+ * This function is invoked from upper layers to initiate transmission.
+ *
+ * Return: NETDEV_TX_OK on success and NETDEV_TX_BUSY when the tx queue is full
+ */
+static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+ struct xcan_priv *priv = netdev_priv(ndev);
+ int ret;
+
+ if (can_dropped_invalid_skb(ndev, skb))
+ return NETDEV_TX_OK;
+
+ if (priv->devtype.flags & XCAN_FLAG_TX_MAILBOXES)
+ ret = xcan_start_xmit_mailbox(skb, ndev);
+ else
+ ret = xcan_start_xmit_fifo(skb, ndev);
+
+ if (ret < 0) {
+ netdev_err(ndev, "BUG!, TX full when queue awake!\n");
+ netif_stop_queue(ndev);
+ return NETDEV_TX_BUSY;
+ }
+
return NETDEV_TX_OK;
}
@@ -489,13 +638,14 @@ static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
* xcan_rx - Is called from CAN isr to complete the received
* frame processing
* @ndev: Pointer to net_device structure
+ * @frame_base: Register offset to the frame to be read
*
* This function is invoked from the CAN isr(poll) to process the Rx frames. It
* does minimal processing and invokes "netif_receive_skb" to complete further
* processing.
* Return: 1 on success and 0 on failure.
*/
-static int xcan_rx(struct net_device *ndev)
+static int xcan_rx(struct net_device *ndev, int frame_base)
{
struct xcan_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &ndev->stats;
@@ -510,9 +660,9 @@ static int xcan_rx(struct net_device *ndev)
}
/* Read a frame from Xilinx zynq CANPS */
- id_xcan = priv->read_reg(priv, XCAN_RXFIFO_ID_OFFSET);
- dlc = priv->read_reg(priv, XCAN_RXFIFO_DLC_OFFSET) >>
- XCAN_DLCR_DLC_SHIFT;
+ id_xcan = priv->read_reg(priv, XCAN_FRAME_ID_OFFSET(frame_base));
+ dlc = priv->read_reg(priv, XCAN_FRAME_DLC_OFFSET(frame_base)) >>
+ XCAN_DLCR_DLC_SHIFT;
/* Change Xilinx CAN data length format to socketCAN data format */
cf->can_dlc = get_can_dlc(dlc);
@@ -535,8 +685,8 @@ static int xcan_rx(struct net_device *ndev)
}
/* DW1/DW2 must always be read to remove message from RXFIFO */
- data[0] = priv->read_reg(priv, XCAN_RXFIFO_DW1_OFFSET);
- data[1] = priv->read_reg(priv, XCAN_RXFIFO_DW2_OFFSET);
+ data[0] = priv->read_reg(priv, XCAN_FRAME_DW1_OFFSET(frame_base));
+ data[1] = priv->read_reg(priv, XCAN_FRAME_DW2_OFFSET(frame_base));
if (!(cf->can_id & CAN_RTR_FLAG)) {
/* Change Xilinx CAN data format to socketCAN data format */
@@ -594,39 +744,19 @@ static void xcan_set_error_state(struct net_device *ndev,
u32 ecr = priv->read_reg(priv, XCAN_ECR_OFFSET);
u32 txerr = ecr & XCAN_ECR_TEC_MASK;
u32 rxerr = (ecr & XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT;
+ enum can_state tx_state = txerr >= rxerr ? new_state : 0;
+ enum can_state rx_state = txerr <= rxerr ? new_state : 0;
+
+ /* non-ERROR states are handled elsewhere */
+ if (WARN_ON(new_state > CAN_STATE_ERROR_PASSIVE))
+ return;
- priv->can.state = new_state;
+ can_change_state(ndev, cf, tx_state, rx_state);
if (cf) {
- cf->can_id |= CAN_ERR_CRTL;
cf->data[6] = txerr;
cf->data[7] = rxerr;
}
-
- switch (new_state) {
- case CAN_STATE_ERROR_PASSIVE:
- priv->can.can_stats.error_passive++;
- if (cf)
- cf->data[1] = (rxerr > 127) ?
- CAN_ERR_CRTL_RX_PASSIVE :
- CAN_ERR_CRTL_TX_PASSIVE;
- break;
- case CAN_STATE_ERROR_WARNING:
- priv->can.can_stats.error_warning++;
- if (cf)
- cf->data[1] |= (txerr > rxerr) ?
- CAN_ERR_CRTL_TX_WARNING :
- CAN_ERR_CRTL_RX_WARNING;
- break;
- case CAN_STATE_ERROR_ACTIVE:
- if (cf)
- cf->data[1] |= CAN_ERR_CRTL_ACTIVE;
- break;
- default:
- /* non-ERROR states are handled elsewhere */
- WARN_ON(1);
- break;
- }
}
/**
@@ -703,7 +833,8 @@ static void xcan_err_interrupt(struct net_device *ndev, u32 isr)
} else {
enum can_state new_state = xcan_current_error_state(ndev);
- xcan_set_error_state(ndev, new_state, skb ? cf : NULL);
+ if (new_state != priv->can.state)
+ xcan_set_error_state(ndev, new_state, skb ? cf : NULL);
}
/* Check for Arbitration lost interrupt */
@@ -725,6 +856,17 @@ static void xcan_err_interrupt(struct net_device *ndev, u32 isr)
}
}
+ /* Check for RX Match Not Finished interrupt */
+ if (isr & XCAN_IXR_RXMNF_MASK) {
+ stats->rx_dropped++;
+ stats->rx_errors++;
+ netdev_err(ndev, "RX match not finished, frame discarded\n");
+ if (skb) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] |= CAN_ERR_CRTL_UNSPEC;
+ }
+ }
+
/* Check for error interrupt */
if (isr & XCAN_IXR_ERROR_MASK) {
if (skb)
@@ -809,6 +951,44 @@ static void xcan_state_interrupt(struct net_device *ndev, u32 isr)
}
/**
+ * xcan_rx_fifo_get_next_frame - Get register offset of next RX frame
+ *
+ * Return: Register offset of the next frame in RX FIFO.
+ */
+static int xcan_rx_fifo_get_next_frame(struct xcan_priv *priv)
+{
+ int offset;
+
+ if (priv->devtype.flags & XCAN_FLAG_RX_FIFO_MULTI) {
+ u32 fsr;
+
+ /* clear RXOK before the is-empty check so that any newly
+ * received frame will reassert it without a race
+ */
+ priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_RXOK_MASK);
+
+ fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
+
+ /* check if RX FIFO is empty */
+ if (!(fsr & XCAN_FSR_FL_MASK))
+ return -ENOENT;
+
+ offset = XCAN_RXMSG_FRAME_OFFSET(fsr & XCAN_FSR_RI_MASK);
+
+ } else {
+ /* check if RX FIFO is empty */
+ if (!(priv->read_reg(priv, XCAN_ISR_OFFSET) &
+ XCAN_IXR_RXNEMP_MASK))
+ return -ENOENT;
+
+ /* frames are read from a static offset */
+ offset = XCAN_RXFIFO_OFFSET;
+ }
+
+ return offset;
+}
+
+/**
* xcan_rx_poll - Poll routine for rx packets (NAPI)
* @napi: napi structure pointer
* @quota: Max number of rx packets to be processed.
@@ -822,14 +1002,24 @@ static int xcan_rx_poll(struct napi_struct *napi, int quota)
{
struct net_device *ndev = napi->dev;
struct xcan_priv *priv = netdev_priv(ndev);
- u32 isr, ier;
+ u32 ier;
int work_done = 0;
-
- isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
- while ((isr & XCAN_IXR_RXNEMP_MASK) && (work_done < quota)) {
- work_done += xcan_rx(ndev);
- priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_RXNEMP_MASK);
- isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
+ int frame_offset;
+
+ while ((frame_offset = xcan_rx_fifo_get_next_frame(priv)) >= 0 &&
+ (work_done < quota)) {
+ work_done += xcan_rx(ndev, frame_offset);
+
+ if (priv->devtype.flags & XCAN_FLAG_RX_FIFO_MULTI)
+ /* increment read index */
+ priv->write_reg(priv, XCAN_FSR_OFFSET,
+ XCAN_FSR_IRI_MASK);
+ else
+ /* clear rx-not-empty (will actually clear only if
+ * empty)
+ */
+ priv->write_reg(priv, XCAN_ICR_OFFSET,
+ XCAN_IXR_RXNEMP_MASK);
}
if (work_done) {
@@ -840,7 +1030,7 @@ static int xcan_rx_poll(struct napi_struct *napi, int quota)
if (work_done < quota) {
napi_complete_done(napi, work_done);
ier = priv->read_reg(priv, XCAN_IER_OFFSET);
- ier |= XCAN_IXR_RXNEMP_MASK;
+ ier |= xcan_rx_int_mask(priv);
priv->write_reg(priv, XCAN_IER_OFFSET, ier);
}
return work_done;
@@ -908,8 +1098,8 @@ static void xcan_tx_interrupt(struct net_device *ndev, u32 isr)
}
while (frames_sent--) {
- can_get_echo_skb(ndev, priv->tx_tail %
- priv->tx_max);
+ stats->tx_bytes += can_get_echo_skb(ndev, priv->tx_tail %
+ priv->tx_max);
priv->tx_tail++;
stats->tx_packets++;
}
@@ -939,6 +1129,7 @@ static irqreturn_t xcan_interrupt(int irq, void *dev_id)
struct xcan_priv *priv = netdev_priv(ndev);
u32 isr, ier;
u32 isr_errors;
+ u32 rx_int_mask = xcan_rx_int_mask(priv);
/* Get the interrupt status from Xilinx CAN */
isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
@@ -958,16 +1149,17 @@ static irqreturn_t xcan_interrupt(int irq, void *dev_id)
/* Check for the type of error interrupt and Processing it */
isr_errors = isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
- XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK);
+ XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK |
+ XCAN_IXR_RXMNF_MASK);
if (isr_errors) {
priv->write_reg(priv, XCAN_ICR_OFFSET, isr_errors);
xcan_err_interrupt(ndev, isr);
}
/* Check for the type of receive interrupt and Processing it */
- if (isr & XCAN_IXR_RXNEMP_MASK) {
+ if (isr & rx_int_mask) {
ier = priv->read_reg(priv, XCAN_IER_OFFSET);
- ier &= ~XCAN_IXR_RXNEMP_MASK;
+ ier &= ~rx_int_mask;
priv->write_reg(priv, XCAN_IER_OFFSET, ier);
napi_schedule(&priv->napi);
}
@@ -1214,13 +1406,35 @@ static const struct dev_pm_ops xcan_dev_pm_ops = {
};
static const struct xcan_devtype_data xcan_zynq_data = {
- .caps = XCAN_CAP_WATERMARK,
+ .bittiming_const = &xcan_bittiming_const,
+ .btr_ts2_shift = XCAN_BTR_TS2_SHIFT,
+ .btr_sjw_shift = XCAN_BTR_SJW_SHIFT,
+ .bus_clk_name = "pclk",
+};
+
+static const struct xcan_devtype_data xcan_axi_data = {
+ .bittiming_const = &xcan_bittiming_const,
+ .btr_ts2_shift = XCAN_BTR_TS2_SHIFT,
+ .btr_sjw_shift = XCAN_BTR_SJW_SHIFT,
+ .bus_clk_name = "s_axi_aclk",
+};
+
+static const struct xcan_devtype_data xcan_canfd_data = {
+ .flags = XCAN_FLAG_EXT_FILTERS |
+ XCAN_FLAG_RXMNF |
+ XCAN_FLAG_TX_MAILBOXES |
+ XCAN_FLAG_RX_FIFO_MULTI,
+ .bittiming_const = &xcan_bittiming_const,
+ .btr_ts2_shift = XCAN_BTR_TS2_SHIFT_CANFD,
+ .btr_sjw_shift = XCAN_BTR_SJW_SHIFT_CANFD,
+ .bus_clk_name = "s_axi_aclk",
};
/* Match table for OF platform binding */
static const struct of_device_id xcan_of_match[] = {
{ .compatible = "xlnx,zynq-can-1.0", .data = &xcan_zynq_data },
- { .compatible = "xlnx,axi-can-1.00.a", },
+ { .compatible = "xlnx,axi-can-1.00.a", .data = &xcan_axi_data },
+ { .compatible = "xlnx,canfd-1.0", .data = &xcan_canfd_data },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(of, xcan_of_match);
@@ -1240,9 +1454,12 @@ static int xcan_probe(struct platform_device *pdev)
struct net_device *ndev;
struct xcan_priv *priv;
const struct of_device_id *of_id;
- int caps = 0;
+ const struct xcan_devtype_data *devtype = &xcan_axi_data;
void __iomem *addr;
- int ret, rx_max, tx_max, tx_fifo_depth;
+ int ret;
+ int rx_max, tx_max;
+ int hw_tx_max, hw_rx_max;
+ const char *hw_tx_max_property;
/* Get the virtual base address for the device */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1252,25 +1469,33 @@ static int xcan_probe(struct platform_device *pdev)
goto err;
}
- ret = of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth",
- &tx_fifo_depth);
- if (ret < 0)
- goto err;
+ of_id = of_match_device(xcan_of_match, &pdev->dev);
+ if (of_id && of_id->data)
+ devtype = of_id->data;
- ret = of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth", &rx_max);
- if (ret < 0)
- goto err;
+ hw_tx_max_property = devtype->flags & XCAN_FLAG_TX_MAILBOXES ?
+ "tx-mailbox-count" : "tx-fifo-depth";
- of_id = of_match_device(xcan_of_match, &pdev->dev);
- if (of_id) {
- const struct xcan_devtype_data *devtype_data = of_id->data;
+ ret = of_property_read_u32(pdev->dev.of_node, hw_tx_max_property,
+ &hw_tx_max);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "missing %s property\n",
+ hw_tx_max_property);
+ goto err;
+ }
- if (devtype_data)
- caps = devtype_data->caps;
+ ret = of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth",
+ &hw_rx_max);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "missing rx-fifo-depth property (mailbox mode is not supported)\n");
+ goto err;
}
- /* There is no way to directly figure out how many frames have been
- * sent when the TXOK interrupt is processed. If watermark programming
+ /* With TX FIFO:
+ *
+ * There is no way to directly figure out how many frames have been
+ * sent when the TXOK interrupt is processed. If TXFEMP
* is supported, we can have 2 frames in the FIFO and use TXFEMP
* to determine if 1 or 2 frames have been sent.
* Theoretically we should be able to use TXFWMEMP to determine up
@@ -1279,12 +1504,20 @@ static int xcan_probe(struct platform_device *pdev)
* than 2 frames in FIFO) is set anyway with no TXOK (a frame was
* sent), which is not a sensible state - possibly TXFWMEMP is not
* completely synchronized with the rest of the bits?
+ *
+ * With TX mailboxes:
+ *
+ * HW sends frames in CAN ID priority order. To preserve FIFO ordering
+ * we submit frames one at a time.
*/
- if (caps & XCAN_CAP_WATERMARK)
- tx_max = min(tx_fifo_depth, 2);
+ if (!(devtype->flags & XCAN_FLAG_TX_MAILBOXES) &&
+ (devtype->flags & XCAN_FLAG_TXFEMP))
+ tx_max = min(hw_tx_max, 2);
else
tx_max = 1;
+ rx_max = hw_rx_max;
+
/* Create a CAN device instance */
ndev = alloc_candev(sizeof(struct xcan_priv), tx_max);
if (!ndev)
@@ -1292,13 +1525,14 @@ static int xcan_probe(struct platform_device *pdev)
priv = netdev_priv(ndev);
priv->dev = &pdev->dev;
- priv->can.bittiming_const = &xcan_bittiming_const;
+ priv->can.bittiming_const = devtype->bittiming_const;
priv->can.do_set_mode = xcan_do_set_mode;
priv->can.do_get_berr_counter = xcan_get_berr_counter;
priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
CAN_CTRLMODE_BERR_REPORTING;
priv->reg_base = addr;
priv->tx_max = tx_max;
+ priv->devtype = *devtype;
spin_lock_init(&priv->tx_lock);
/* Get IRQ for the device */
@@ -1316,22 +1550,12 @@ static int xcan_probe(struct platform_device *pdev)
ret = PTR_ERR(priv->can_clk);
goto err_free;
}
- /* Check for type of CAN device */
- if (of_device_is_compatible(pdev->dev.of_node,
- "xlnx,zynq-can-1.0")) {
- priv->bus_clk = devm_clk_get(&pdev->dev, "pclk");
- if (IS_ERR(priv->bus_clk)) {
- dev_err(&pdev->dev, "bus clock not found\n");
- ret = PTR_ERR(priv->bus_clk);
- goto err_free;
- }
- } else {
- priv->bus_clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
- if (IS_ERR(priv->bus_clk)) {
- dev_err(&pdev->dev, "bus clock not found\n");
- ret = PTR_ERR(priv->bus_clk);
- goto err_free;
- }
+
+ priv->bus_clk = devm_clk_get(&pdev->dev, devtype->bus_clk_name);
+ if (IS_ERR(priv->bus_clk)) {
+ dev_err(&pdev->dev, "bus clock not found\n");
+ ret = PTR_ERR(priv->bus_clk);
+ goto err_free;
}
priv->write_reg = xcan_write_reg_le;
@@ -1364,9 +1588,9 @@ static int xcan_probe(struct platform_device *pdev)
pm_runtime_put(&pdev->dev);
- netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth: actual %d, using %d\n",
- priv->reg_base, ndev->irq, priv->can.clock.freq,
- tx_fifo_depth, priv->tx_max);
+ netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx buffers: actual %d, using %d\n",
+ priv->reg_base, ndev->irq, priv->can.clock.freq,
+ hw_tx_max, priv->tx_max);
return 0;