2 * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
3 * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>
5 * Copyright (C) 2016 PEAK System-Technik GmbH
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the version 2 of the GNU General Public License
9 * as published by the Free Software Foundation
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
17 #include <linux/can.h>
18 #include <linux/can/dev.h>
20 #include "peak_canfd_user.h"
22 /* internal IP core cache size (used as default echo skbs max number) */
23 #define PCANFD_ECHO_SKB_MAX 24
25 /* bittiming ranges of the PEAK-System PC CAN-FD interfaces */
26 static const struct can_bittiming_const peak_canfd_nominal_const = {
29 .tseg1_max = (1 << PUCAN_TSLOW_TSGEG1_BITS),
31 .tseg2_max = (1 << PUCAN_TSLOW_TSGEG2_BITS),
32 .sjw_max = (1 << PUCAN_TSLOW_SJW_BITS),
34 .brp_max = (1 << PUCAN_TSLOW_BRP_BITS),
38 static const struct can_bittiming_const peak_canfd_data_const = {
41 .tseg1_max = (1 << PUCAN_TFAST_TSGEG1_BITS),
43 .tseg2_max = (1 << PUCAN_TFAST_TSGEG2_BITS),
44 .sjw_max = (1 << PUCAN_TFAST_SJW_BITS),
46 .brp_max = (1 << PUCAN_TFAST_BRP_BITS),
50 static struct peak_canfd_priv *pucan_init_cmd(struct peak_canfd_priv *priv)
56 static void *pucan_add_cmd(struct peak_canfd_priv *priv, int cmd_op)
58 struct pucan_command *cmd;
60 if (priv->cmd_len + sizeof(*cmd) > priv->cmd_maxlen)
63 cmd = priv->cmd_buffer + priv->cmd_len;
65 /* reset all unused bit to default */
66 memset(cmd, 0, sizeof(*cmd));
68 cmd->opcode_channel = pucan_cmd_opcode_channel(priv->index, cmd_op);
69 priv->cmd_len += sizeof(*cmd);
74 static int pucan_write_cmd(struct peak_canfd_priv *priv)
79 err = priv->pre_cmd(priv);
84 err = priv->write_cmd(priv);
89 err = priv->post_cmd(priv);
94 /* uCAN commands interface functions */
95 static int pucan_set_reset_mode(struct peak_canfd_priv *priv)
97 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RESET_MODE);
98 return pucan_write_cmd(priv);
101 static int pucan_set_normal_mode(struct peak_canfd_priv *priv)
105 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_NORMAL_MODE);
106 err = pucan_write_cmd(priv);
108 priv->can.state = CAN_STATE_ERROR_ACTIVE;
113 static int pucan_set_listen_only_mode(struct peak_canfd_priv *priv)
117 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_LISTEN_ONLY_MODE);
118 err = pucan_write_cmd(priv);
120 priv->can.state = CAN_STATE_ERROR_ACTIVE;
125 static int pucan_set_timing_slow(struct peak_canfd_priv *priv,
126 const struct can_bittiming *pbt)
128 struct pucan_timing_slow *cmd;
130 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_SLOW);
132 cmd->sjw_t = PUCAN_TSLOW_SJW_T(pbt->sjw - 1,
133 priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES);
134 cmd->tseg1 = PUCAN_TSLOW_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1);
135 cmd->tseg2 = PUCAN_TSLOW_TSEG2(pbt->phase_seg2 - 1);
136 cmd->brp = cpu_to_le16(PUCAN_TSLOW_BRP(pbt->brp - 1));
138 cmd->ewl = 96; /* default */
140 netdev_dbg(priv->ndev,
141 "nominal: brp=%u tseg1=%u tseg2=%u sjw=%u\n",
142 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw_t);
144 return pucan_write_cmd(priv);
147 static int pucan_set_timing_fast(struct peak_canfd_priv *priv,
148 const struct can_bittiming *pbt)
150 struct pucan_timing_fast *cmd;
152 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_FAST);
154 cmd->sjw = PUCAN_TFAST_SJW(pbt->sjw - 1);
155 cmd->tseg1 = PUCAN_TFAST_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1);
156 cmd->tseg2 = PUCAN_TFAST_TSEG2(pbt->phase_seg2 - 1);
157 cmd->brp = cpu_to_le16(PUCAN_TFAST_BRP(pbt->brp - 1));
159 netdev_dbg(priv->ndev,
160 "data: brp=%u tseg1=%u tseg2=%u sjw=%u\n",
161 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw);
163 return pucan_write_cmd(priv);
166 static int pucan_set_std_filter(struct peak_canfd_priv *priv, u8 row, u32 mask)
168 struct pucan_std_filter *cmd;
170 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_STD_FILTER);
172 /* all the 11-bits CAN ID values are represented by one bit in a
173 * 64 rows array of 32 bits: the upper 6 bits of the CAN ID select the
174 * row while the lowest 5 bits select the bit in that row.
184 /* set/unset bits in the row */
185 cmd->mask = cpu_to_le32(mask);
187 return pucan_write_cmd(priv);
190 static int pucan_tx_abort(struct peak_canfd_priv *priv, u16 flags)
192 struct pucan_tx_abort *cmd;
194 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TX_ABORT);
196 cmd->flags = cpu_to_le16(flags);
198 return pucan_write_cmd(priv);
201 static int pucan_clr_err_counters(struct peak_canfd_priv *priv)
203 struct pucan_wr_err_cnt *cmd;
205 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_WR_ERR_CNT);
207 cmd->sel_mask = cpu_to_le16(PUCAN_WRERRCNT_TE | PUCAN_WRERRCNT_RE);
211 return pucan_write_cmd(priv);
214 static int pucan_set_options(struct peak_canfd_priv *priv, u16 opt_mask)
216 struct pucan_options *cmd;
218 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_EN_OPTION);
220 cmd->options = cpu_to_le16(opt_mask);
222 return pucan_write_cmd(priv);
225 static int pucan_clr_options(struct peak_canfd_priv *priv, u16 opt_mask)
227 struct pucan_options *cmd;
229 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_CLR_DIS_OPTION);
231 cmd->options = cpu_to_le16(opt_mask);
233 return pucan_write_cmd(priv);
236 static int pucan_setup_rx_barrier(struct peak_canfd_priv *priv)
238 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RX_BARRIER);
240 return pucan_write_cmd(priv);
243 /* handle the reception of one CAN frame */
244 static int pucan_handle_can_rx(struct peak_canfd_priv *priv,
245 struct pucan_rx_msg *msg)
247 struct net_device_stats *stats = &priv->ndev->stats;
248 struct canfd_frame *cf;
250 const u16 rx_msg_flags = le16_to_cpu(msg->flags);
253 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN)
254 cf_len = can_dlc2len(get_canfd_dlc(pucan_msg_get_dlc(msg)));
256 cf_len = get_can_dlc(pucan_msg_get_dlc(msg));
258 /* if this frame is an echo, */
259 if ((rx_msg_flags & PUCAN_MSG_LOOPED_BACK) &&
260 !(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE)) {
264 spin_lock_irqsave(&priv->echo_lock, flags);
265 n = can_get_echo_skb(priv->ndev, msg->client);
266 spin_unlock_irqrestore(&priv->echo_lock, flags);
268 /* count bytes of the echo instead of skb */
269 stats->tx_bytes += cf_len;
273 /* restart tx queue only if a slot is free */
274 netif_wake_queue(priv->ndev);
280 /* otherwise, it should be pushed into rx fifo */
281 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) {
282 /* CANFD frame case */
283 skb = alloc_canfd_skb(priv->ndev, &cf);
287 if (rx_msg_flags & PUCAN_MSG_BITRATE_SWITCH)
288 cf->flags |= CANFD_BRS;
290 if (rx_msg_flags & PUCAN_MSG_ERROR_STATE_IND)
291 cf->flags |= CANFD_ESI;
293 /* CAN 2.0 frame case */
294 skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cf);
299 cf->can_id = le32_to_cpu(msg->can_id);
302 if (rx_msg_flags & PUCAN_MSG_EXT_ID)
303 cf->can_id |= CAN_EFF_FLAG;
305 if (rx_msg_flags & PUCAN_MSG_RTR)
306 cf->can_id |= CAN_RTR_FLAG;
308 memcpy(cf->data, msg->d, cf->len);
310 stats->rx_bytes += cf->len;
318 /* handle rx/tx error counters notification */
319 static int pucan_handle_error(struct peak_canfd_priv *priv,
320 struct pucan_error_msg *msg)
322 priv->bec.txerr = msg->tx_err_cnt;
323 priv->bec.rxerr = msg->rx_err_cnt;
328 /* handle status notification */
329 static int pucan_handle_status(struct peak_canfd_priv *priv,
330 struct pucan_status_msg *msg)
332 struct net_device *ndev = priv->ndev;
333 struct net_device_stats *stats = &ndev->stats;
334 struct can_frame *cf;
337 /* this STATUS is the CNF of the RX_BARRIER: Tx path can be setup */
338 if (pucan_status_is_rx_barrier(msg)) {
341 if (priv->enable_tx_path) {
342 int err = priv->enable_tx_path(priv);
348 /* restart network queue only if echo skb array is free */
349 spin_lock_irqsave(&priv->echo_lock, flags);
351 if (!priv->can.echo_skb[priv->echo_idx]) {
352 spin_unlock_irqrestore(&priv->echo_lock, flags);
354 netif_wake_queue(ndev);
356 spin_unlock_irqrestore(&priv->echo_lock, flags);
362 skb = alloc_can_err_skb(ndev, &cf);
364 /* test state error bits according to their priority */
365 if (pucan_status_is_busoff(msg)) {
366 netdev_dbg(ndev, "Bus-off entry status\n");
367 priv->can.state = CAN_STATE_BUS_OFF;
368 priv->can.can_stats.bus_off++;
371 cf->can_id |= CAN_ERR_BUSOFF;
373 } else if (pucan_status_is_passive(msg)) {
374 netdev_dbg(ndev, "Error passive status\n");
375 priv->can.state = CAN_STATE_ERROR_PASSIVE;
376 priv->can.can_stats.error_passive++;
378 cf->can_id |= CAN_ERR_CRTL;
379 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
380 CAN_ERR_CRTL_TX_PASSIVE :
381 CAN_ERR_CRTL_RX_PASSIVE;
382 cf->data[6] = priv->bec.txerr;
383 cf->data[7] = priv->bec.rxerr;
386 } else if (pucan_status_is_warning(msg)) {
387 netdev_dbg(ndev, "Error warning status\n");
388 priv->can.state = CAN_STATE_ERROR_WARNING;
389 priv->can.can_stats.error_warning++;
391 cf->can_id |= CAN_ERR_CRTL;
392 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
393 CAN_ERR_CRTL_TX_WARNING :
394 CAN_ERR_CRTL_RX_WARNING;
395 cf->data[6] = priv->bec.txerr;
396 cf->data[7] = priv->bec.rxerr;
399 } else if (priv->can.state != CAN_STATE_ERROR_ACTIVE) {
400 /* back to ERROR_ACTIVE */
401 netdev_dbg(ndev, "Error active status\n");
402 can_change_state(ndev, cf, CAN_STATE_ERROR_ACTIVE,
403 CAN_STATE_ERROR_ACTIVE);
415 stats->rx_bytes += cf->can_dlc;
421 /* handle uCAN Rx overflow notification */
422 static int pucan_handle_cache_critical(struct peak_canfd_priv *priv)
424 struct net_device_stats *stats = &priv->ndev->stats;
425 struct can_frame *cf;
428 stats->rx_over_errors++;
431 skb = alloc_can_err_skb(priv->ndev, &cf);
437 cf->can_id |= CAN_ERR_CRTL;
438 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
440 cf->data[6] = priv->bec.txerr;
441 cf->data[7] = priv->bec.rxerr;
443 stats->rx_bytes += cf->can_dlc;
450 /* handle a single uCAN message */
451 int peak_canfd_handle_msg(struct peak_canfd_priv *priv,
452 struct pucan_rx_msg *msg)
454 u16 msg_type = le16_to_cpu(msg->type);
455 int msg_size = le16_to_cpu(msg->size);
458 if (!msg_size || !msg_type) {
459 /* null packet found: end of list */
464 case PUCAN_MSG_CAN_RX:
465 err = pucan_handle_can_rx(priv, (struct pucan_rx_msg *)msg);
467 case PUCAN_MSG_ERROR:
468 err = pucan_handle_error(priv, (struct pucan_error_msg *)msg);
470 case PUCAN_MSG_STATUS:
471 err = pucan_handle_status(priv, (struct pucan_status_msg *)msg);
473 case PUCAN_MSG_CACHE_CRITICAL:
474 err = pucan_handle_cache_critical(priv);
487 /* handle a list of rx_count messages from rx_msg memory address */
488 int peak_canfd_handle_msgs_list(struct peak_canfd_priv *priv,
489 struct pucan_rx_msg *msg_list, int msg_count)
491 void *msg_ptr = msg_list;
494 for (i = 0; i < msg_count; i++) {
495 msg_size = peak_canfd_handle_msg(priv, msg_ptr);
497 /* a null packet can be found at the end of a list */
510 static int peak_canfd_start(struct peak_canfd_priv *priv)
514 err = pucan_clr_err_counters(priv);
523 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
524 err = pucan_set_listen_only_mode(priv);
526 err = pucan_set_normal_mode(priv);
532 static void peak_canfd_stop(struct peak_canfd_priv *priv)
536 /* go back to RESET mode */
537 err = pucan_set_reset_mode(priv);
539 netdev_err(priv->ndev, "channel %u reset failed\n",
542 /* abort last Tx (MUST be done in RESET mode only!) */
543 pucan_tx_abort(priv, PUCAN_TX_ABORT_FLUSH);
547 static int peak_canfd_set_mode(struct net_device *ndev, enum can_mode mode)
549 struct peak_canfd_priv *priv = netdev_priv(ndev);
553 peak_canfd_start(priv);
554 netif_wake_queue(ndev);
563 static int peak_canfd_get_berr_counter(const struct net_device *ndev,
564 struct can_berr_counter *bec)
566 struct peak_canfd_priv *priv = netdev_priv(ndev);
572 static int peak_canfd_open(struct net_device *ndev)
574 struct peak_canfd_priv *priv = netdev_priv(ndev);
577 err = open_candev(ndev);
579 netdev_err(ndev, "open_candev() failed, error %d\n", err);
583 err = pucan_set_reset_mode(priv);
587 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
588 if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
589 err = pucan_clr_options(priv, PUCAN_OPTION_CANDFDISO);
591 err = pucan_set_options(priv, PUCAN_OPTION_CANDFDISO);
597 /* set option: get rx/tx error counters */
598 err = pucan_set_options(priv, PUCAN_OPTION_ERROR);
602 /* accept all standard CAN ID */
603 for (i = 0; i <= PUCAN_FLTSTD_ROW_IDX_MAX; i++)
604 pucan_set_std_filter(priv, i, 0xffffffff);
606 err = peak_canfd_start(priv);
610 /* receiving the RB status says when Tx path is ready */
611 err = pucan_setup_rx_barrier(priv);
621 static int peak_canfd_set_bittiming(struct net_device *ndev)
623 struct peak_canfd_priv *priv = netdev_priv(ndev);
625 return pucan_set_timing_slow(priv, &priv->can.bittiming);
628 static int peak_canfd_set_data_bittiming(struct net_device *ndev)
630 struct peak_canfd_priv *priv = netdev_priv(ndev);
632 return pucan_set_timing_fast(priv, &priv->can.data_bittiming);
635 static int peak_canfd_close(struct net_device *ndev)
637 struct peak_canfd_priv *priv = netdev_priv(ndev);
639 netif_stop_queue(ndev);
640 peak_canfd_stop(priv);
646 static netdev_tx_t peak_canfd_start_xmit(struct sk_buff *skb,
647 struct net_device *ndev)
649 struct peak_canfd_priv *priv = netdev_priv(ndev);
650 struct net_device_stats *stats = &ndev->stats;
651 struct canfd_frame *cf = (struct canfd_frame *)skb->data;
652 struct pucan_tx_msg *msg;
653 u16 msg_size, msg_flags;
655 bool should_stop_tx_queue;
659 if (can_dropped_invalid_skb(ndev, skb))
662 msg_size = ALIGN(sizeof(*msg) + cf->len, 4);
663 msg = priv->alloc_tx_msg(priv, msg_size, &room_left);
665 /* should never happen except under bus-off condition and (auto-)restart
670 netif_stop_queue(ndev);
671 return NETDEV_TX_BUSY;
674 msg->size = cpu_to_le16(msg_size);
675 msg->type = cpu_to_le16(PUCAN_MSG_CAN_TX);
678 if (cf->can_id & CAN_EFF_FLAG) {
679 msg_flags |= PUCAN_MSG_EXT_ID;
680 msg->can_id = cpu_to_le32(cf->can_id & CAN_EFF_MASK);
682 msg->can_id = cpu_to_le32(cf->can_id & CAN_SFF_MASK);
685 if (can_is_canfd_skb(skb)) {
686 /* CAN FD frame format */
687 can_dlc = can_len2dlc(cf->len);
689 msg_flags |= PUCAN_MSG_EXT_DATA_LEN;
691 if (cf->flags & CANFD_BRS)
692 msg_flags |= PUCAN_MSG_BITRATE_SWITCH;
694 if (cf->flags & CANFD_ESI)
695 msg_flags |= PUCAN_MSG_ERROR_STATE_IND;
697 /* CAN 2.0 frame format */
700 if (cf->can_id & CAN_RTR_FLAG)
701 msg_flags |= PUCAN_MSG_RTR;
704 /* always ask loopback for echo management */
705 msg_flags |= PUCAN_MSG_LOOPED_BACK;
707 /* set driver specific bit to differentiate with application loopback */
708 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
709 msg_flags |= PUCAN_MSG_SELF_RECEIVE;
711 msg->flags = cpu_to_le16(msg_flags);
712 msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(priv->index, can_dlc);
713 memcpy(msg->d, cf->data, cf->len);
715 /* struct msg client field is used as an index in the echo skbs ring */
716 msg->client = priv->echo_idx;
718 spin_lock_irqsave(&priv->echo_lock, flags);
720 /* prepare and save echo skb in internal slot */
721 can_put_echo_skb(skb, ndev, priv->echo_idx);
723 /* move echo index to the next slot */
724 priv->echo_idx = (priv->echo_idx + 1) % priv->can.echo_skb_max;
726 /* if next slot is not free, stop network queue (no slot free in echo
727 * skb ring means that the controller did not write these frames on
728 * the bus: no need to continue).
730 should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]);
732 spin_unlock_irqrestore(&priv->echo_lock, flags);
734 /* write the skb on the interface */
735 priv->write_tx_msg(priv, msg);
737 /* stop network tx queue if not enough room to save one more msg too */
738 if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
739 should_stop_tx_queue |= (room_left <
740 (sizeof(*msg) + CANFD_MAX_DLEN));
742 should_stop_tx_queue |= (room_left <
743 (sizeof(*msg) + CAN_MAX_DLEN));
745 if (should_stop_tx_queue)
746 netif_stop_queue(ndev);
751 static const struct net_device_ops peak_canfd_netdev_ops = {
752 .ndo_open = peak_canfd_open,
753 .ndo_stop = peak_canfd_close,
754 .ndo_start_xmit = peak_canfd_start_xmit,
755 .ndo_change_mtu = can_change_mtu,
758 struct net_device *alloc_peak_canfd_dev(int sizeof_priv, int index,
761 struct net_device *ndev;
762 struct peak_canfd_priv *priv;
764 /* we DO support local echo */
765 if (echo_skb_max < 0)
766 echo_skb_max = PCANFD_ECHO_SKB_MAX;
768 /* allocate the candev object */
769 ndev = alloc_candev(sizeof_priv, echo_skb_max);
773 priv = netdev_priv(ndev);
775 /* complete now socket-can initialization side */
776 priv->can.state = CAN_STATE_STOPPED;
777 priv->can.bittiming_const = &peak_canfd_nominal_const;
778 priv->can.data_bittiming_const = &peak_canfd_data_const;
780 priv->can.do_set_mode = peak_canfd_set_mode;
781 priv->can.do_get_berr_counter = peak_canfd_get_berr_counter;
782 priv->can.do_set_bittiming = peak_canfd_set_bittiming;
783 priv->can.do_set_data_bittiming = peak_canfd_set_data_bittiming;
784 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
785 CAN_CTRLMODE_LISTENONLY |
786 CAN_CTRLMODE_3_SAMPLES |
788 CAN_CTRLMODE_FD_NON_ISO |
789 CAN_CTRLMODE_BERR_REPORTING;
794 spin_lock_init(&priv->echo_lock);
796 ndev->flags |= IFF_ECHO;
797 ndev->netdev_ops = &peak_canfd_netdev_ops;
798 ndev->dev_id = index;