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can: xilinx_can: Add support for CANFD FD frames

Browse source 
CANFD IP supports both CAN and CAN FD frames,
Existing driver supports only CAN frames, This patch
adds support for CAN FD frames.

Signed-off-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Appana Durga Kedareswara rao 2019-03-18 17:02:44 +05:30 committed by Marc Kleine-Budde
parent 8dce7ea41a
commit c223da6893
1 changed files with 214 additions and 16 deletions
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230
drivers/net/can/xilinx_can.c
View file

@ -50,6 +50,10 @@ enum xcan_reg {
XCAN_AFR_OFFSET = 0x60, /* Acceptance Filter */
/* only on CAN FD cores */
XCAN_F_BRPR_OFFSET = 0x088, /* Data Phase Baud Rate
* Prescalar
*/
XCAN_F_BTR_OFFSET = 0x08C, /* Data Phase Bit Timing */
XCAN_TRR_OFFSET = 0x0090, /* TX Buffer Ready Request */
XCAN_AFR_EXT_OFFSET = 0x00E0, /* Acceptance Filter */
XCAN_FSR_OFFSET = 0x00E8, /* RX FIFO Status */
@ -62,6 +66,8 @@ enum xcan_reg {
#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 XCANFD_FRAME_DW_OFFSET(frame_base, n) (((frame_base) + 0x08) + \
((n) * XCAN_CANFD_FRAME_SIZE))
#define XCAN_CANFD_FRAME_SIZE 0x48
#define XCAN_TXMSG_FRAME_OFFSET(n) (XCAN_TXMSG_BASE_OFFSET + \
@ -120,6 +126,8 @@ enum xcan_reg {
#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 */
#define XCAN_DLCR_EDL_MASK 0x08000000 /* EDL Mask in DLC */
#define XCAN_DLCR_BRS_MASK 0x04000000 /* BRS Mask in DLC */
/* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
#define XCAN_BTR_SJW_SHIFT 7 /* Synchronous jump width */
@ -133,6 +141,7 @@ enum xcan_reg {
/* CAN frame length constants */
#define XCAN_FRAME_MAX_DATA_LEN 8
#define XCANFD_DW_BYTES 4
#define XCAN_TIMEOUT (1 * HZ)
/* TX-FIFO-empty interrupt available */
@ -213,6 +222,7 @@ static const struct can_bittiming_const xcan_bittiming_const = {
.brp_inc = 1,
};
/* AXI CANFD Arbitration Bittiming constants as per AXI CANFD 1.0 spec */
static const struct can_bittiming_const xcan_bittiming_const_canfd = {
.name = DRIVER_NAME,
.tseg1_min = 1,
@ -225,6 +235,20 @@ static const struct can_bittiming_const xcan_bittiming_const_canfd = {
.brp_inc = 1,
};
/* AXI CANFD Data Bittiming constants as per AXI CANFD 1.0 specs */
static struct can_bittiming_const xcan_data_bittiming_const_canfd = {
.name = DRIVER_NAME,
.tseg1_min = 1,
.tseg1_max = 16,
.tseg2_min = 1,
.tseg2_max = 8,
.sjw_max = 8,
.brp_min = 1,
.brp_max = 256,
.brp_inc = 1,
};
/* AXI CANFD 2.0 Arbitration Bittiming constants as per AXI CANFD 2.0 spec */
static const struct can_bittiming_const xcan_bittiming_const_canfd2 = {
.name = DRIVER_NAME,
.tseg1_min = 1,
@ -237,6 +261,19 @@ static const struct can_bittiming_const xcan_bittiming_const_canfd2 = {
.brp_inc = 1,
};
/* AXI CANFD 2.0 Data Bittiming constants as per AXI CANFD 2.0 spec */
static struct can_bittiming_const xcan_data_bittiming_const_canfd2 = {
.name = DRIVER_NAME,
.tseg1_min = 1,
.tseg1_max = 32,
.tseg2_min = 1,
.tseg2_max = 16,
.sjw_max = 16,
.brp_min = 1,
.brp_max = 256,
.brp_inc = 1,
};
/**
* xcan_write_reg_le - Write a value to the device register little endian
* @priv: Driver private data structure
@ -351,6 +388,7 @@ static int xcan_set_bittiming(struct net_device *ndev)
{
struct xcan_priv *priv = netdev_priv(ndev);
struct can_bittiming *bt = &priv->can.bittiming;
struct can_bittiming *dbt = &priv->can.data_bittiming;
u32 btr0, btr1;
u32 is_config_mode;
@ -380,6 +418,24 @@ static int xcan_set_bittiming(struct net_device *ndev)
priv->write_reg(priv, XCAN_BRPR_OFFSET, btr0);
priv->write_reg(priv, XCAN_BTR_OFFSET, btr1);
if (priv->devtype.cantype == XAXI_CANFD ||
priv->devtype.cantype == XAXI_CANFD_2_0) {
/* Setting Baud Rate prescalar value in F_BRPR Register */
btr0 = dbt->brp - 1;
/* Setting Time Segment 1 in BTR Register */
btr1 = dbt->prop_seg + bt->phase_seg1 - 1;
/* Setting Time Segment 2 in BTR Register */
btr1 |= (dbt->phase_seg2 - 1) << priv->devtype.btr_ts2_shift;
/* Setting Synchronous jump width in BTR Register */
btr1 |= (dbt->sjw - 1) << priv->devtype.btr_sjw_shift;
priv->write_reg(priv, XCAN_F_BRPR_OFFSET, btr0);
priv->write_reg(priv, XCAN_F_BTR_OFFSET, btr1);
}
netdev_dbg(ndev, "BRPR=0x%08x, BTR=0x%08x\n",
priv->read_reg(priv, XCAN_BRPR_OFFSET),
priv->read_reg(priv, XCAN_BTR_OFFSET));
@ -499,7 +555,8 @@ static void xcan_write_frame(struct xcan_priv *priv, struct sk_buff *skb,
int frame_offset)
{
u32 id, dlc, data[2] = {0, 0};
struct can_frame *cf = (struct can_frame *)skb->data;
struct canfd_frame *cf = (struct canfd_frame *)skb->data;
u32 ramoff, dwindex = 0, i;
/* Watch carefully on the bit sequence */
if (cf->can_id & CAN_EFF_FLAG) {
@ -528,26 +585,44 @@ static void xcan_write_frame(struct xcan_priv *priv, struct sk_buff *skb,
id |= XCAN_IDR_SRR_MASK;
}
dlc = cf->can_dlc << XCAN_DLCR_DLC_SHIFT;
if (cf->can_dlc > 0)
data[0] = be32_to_cpup((__be32 *)(cf->data + 0));
if (cf->can_dlc > 4)
data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
dlc = can_len2dlc(cf->len) << XCAN_DLCR_DLC_SHIFT;
if (can_is_canfd_skb(skb)) {
if (cf->flags & CANFD_BRS)
dlc |= XCAN_DLCR_BRS_MASK;
dlc |= XCAN_DLCR_EDL_MASK;
}
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]);
if (priv->devtype.cantype == XAXI_CANFD ||
priv->devtype.cantype == XAXI_CANFD_2_0) {
for (i = 0; i < cf->len; i += 4) {
ramoff = XCANFD_FRAME_DW_OFFSET(frame_offset, dwindex) +
(dwindex * XCANFD_DW_BYTES);
priv->write_reg(priv, ramoff,
be32_to_cpup((__be32 *)(cf->data + i)));
dwindex++;
}
} else {
if (cf->len > 0)
data[0] = be32_to_cpup((__be32 *)(cf->data + 0));
if (cf->len > 4)
data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
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]);
}
}
}
@ -724,6 +799,113 @@ static int xcan_rx(struct net_device *ndev, int frame_base)
return 1;
}
/**
* xcanfd_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 xcanfd_rx(struct net_device *ndev, int frame_base)
{
struct xcan_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &ndev->stats;
struct canfd_frame *cf;
struct sk_buff *skb;
u32 id_xcan, dlc, data[2] = {0, 0}, dwindex = 0, i, fsr, readindex;
fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
if (fsr & XCAN_FSR_FL_MASK) {
readindex = fsr & XCAN_FSR_RI_MASK;
id_xcan = priv->read_reg(priv,
XCAN_FRAME_ID_OFFSET(frame_base));
dlc = priv->read_reg(priv, XCAN_FRAME_DLC_OFFSET(frame_base));
if (dlc & XCAN_DLCR_EDL_MASK)
skb = alloc_canfd_skb(ndev, &cf);
else
skb = alloc_can_skb(ndev, (struct can_frame **)&cf);
if (unlikely(!skb)) {
stats->rx_dropped++;
return 0;
}
/* Change Xilinx CANFD data length format to socketCAN data
* format
*/
if (dlc & XCAN_DLCR_EDL_MASK)
cf->len = can_dlc2len((dlc & XCAN_DLCR_DLC_MASK) >>
XCAN_DLCR_DLC_SHIFT);
else
cf->len = get_can_dlc((dlc & XCAN_DLCR_DLC_MASK) >>
XCAN_DLCR_DLC_SHIFT);
/* Change Xilinx CAN ID format to socketCAN ID format */
if (id_xcan & XCAN_IDR_IDE_MASK) {
/* The received frame is an Extended format frame */
cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >> 3;
cf->can_id |= (id_xcan & XCAN_IDR_ID2_MASK) >>
XCAN_IDR_ID2_SHIFT;
cf->can_id |= CAN_EFF_FLAG;
if (id_xcan & XCAN_IDR_RTR_MASK)
cf->can_id |= CAN_RTR_FLAG;
} else {
/* The received frame is a standard format frame */
cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >>
XCAN_IDR_ID1_SHIFT;
if (!(dlc & XCAN_DLCR_EDL_MASK) && (id_xcan &
XCAN_IDR_SRR_MASK))
cf->can_id |= CAN_RTR_FLAG;
}
/* Check the frame received is FD or not*/
if (dlc & XCAN_DLCR_EDL_MASK) {
for (i = 0; i < cf->len; i += 4) {
if (priv->devtype.flags & XCAN_FLAG_CANFD_2)
data[0] = priv->read_reg(priv,
(XCAN_RXMSG_2_FRAME_OFFSET(readindex) +
(dwindex * XCANFD_DW_BYTES)));
else
data[0] = priv->read_reg(priv,
(XCAN_RXMSG_FRAME_OFFSET(readindex) +
(dwindex * XCANFD_DW_BYTES)));
*(__be32 *)(cf->data + i) =
cpu_to_be32(data[0]);
dwindex++;
}
} else {
for (i = 0; i < cf->len; i += 4) {
if (priv->devtype.flags & XCAN_FLAG_CANFD_2)
data[0] = priv->read_reg(priv,
XCAN_RXMSG_2_FRAME_OFFSET(readindex) + i);
else
data[0] = priv->read_reg(priv,
XCAN_RXMSG_FRAME_OFFSET(readindex) + i);
*(__be32 *)(cf->data + i) =
cpu_to_be32(data[0]);
}
}
/* Update FSR Register so that next packet will save to
* buffer
*/
fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
fsr |= XCAN_FSR_IRI_MASK;
priv->write_reg(priv, XCAN_FSR_OFFSET, fsr);
fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
stats->rx_bytes += cf->len;
stats->rx_packets++;
netif_receive_skb(skb);
return 1;
}
/* If FSR Register is not updated with fill level */
return 0;
}
/**
* xcan_current_error_state - Get current error state from HW
* @ndev: Pointer to net_device structure
@ -1035,7 +1217,10 @@ static int xcan_rx_poll(struct napi_struct *napi, int quota)
while ((frame_offset = xcan_rx_fifo_get_next_frame(priv)) >= 0 &&
(work_done < quota)) {
work_done += xcan_rx(ndev, frame_offset);
if (xcan_rx_int_mask(priv) & XCAN_IXR_RXOK_MASK)
work_done += xcanfd_rx(ndev, frame_offset);
else
work_done += xcan_rx(ndev, frame_offset);
if (priv->devtype.flags & XCAN_FLAG_RX_FIFO_MULTI)
/* increment read index */
@ -1577,6 +1762,19 @@ static int xcan_probe(struct platform_device *pdev)
priv->can.do_get_berr_counter = xcan_get_berr_counter;
priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
CAN_CTRLMODE_BERR_REPORTING;
if (devtype->cantype == XAXI_CANFD)
priv->can.data_bittiming_const =
&xcan_data_bittiming_const_canfd;
if (devtype->cantype == XAXI_CANFD_2_0)
priv->can.data_bittiming_const =
&xcan_data_bittiming_const_canfd2;
if (devtype->cantype == XAXI_CANFD ||
devtype->cantype == XAXI_CANFD_2_0)
priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
priv->reg_base = addr;
priv->tx_max = tx_max;
priv->devtype = *devtype;