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) {
262 spin_lock_irqsave(&priv->echo_lock, flags);
263 can_get_echo_skb(priv->ndev, msg->client);
265 /* count bytes of the echo instead of skb */
266 stats->tx_bytes += cf_len;
269 /* restart tx queue (a slot is free) */
270 netif_wake_queue(priv->ndev);
272 spin_unlock_irqrestore(&priv->echo_lock, flags);
274 /* if this frame is only an echo, stop here. Otherwise,
275 * continue to push this application self-received frame into
278 if (!(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE))
282 /* otherwise, it should be pushed into rx fifo */
283 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) {
284 /* CANFD frame case */
285 skb = alloc_canfd_skb(priv->ndev, &cf);
289 if (rx_msg_flags & PUCAN_MSG_BITRATE_SWITCH)
290 cf->flags |= CANFD_BRS;
292 if (rx_msg_flags & PUCAN_MSG_ERROR_STATE_IND)
293 cf->flags |= CANFD_ESI;
295 /* CAN 2.0 frame case */
296 skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cf);
301 cf->can_id = le32_to_cpu(msg->can_id);
304 if (rx_msg_flags & PUCAN_MSG_EXT_ID)
305 cf->can_id |= CAN_EFF_FLAG;
307 if (rx_msg_flags & PUCAN_MSG_RTR)
308 cf->can_id |= CAN_RTR_FLAG;
310 memcpy(cf->data, msg->d, cf->len);
312 stats->rx_bytes += cf->len;
320 /* handle rx/tx error counters notification */
321 static int pucan_handle_error(struct peak_canfd_priv *priv,
322 struct pucan_error_msg *msg)
324 priv->bec.txerr = msg->tx_err_cnt;
325 priv->bec.rxerr = msg->rx_err_cnt;
330 /* handle status notification */
331 static int pucan_handle_status(struct peak_canfd_priv *priv,
332 struct pucan_status_msg *msg)
334 struct net_device *ndev = priv->ndev;
335 struct net_device_stats *stats = &ndev->stats;
336 struct can_frame *cf;
339 /* this STATUS is the CNF of the RX_BARRIER: Tx path can be setup */
340 if (pucan_status_is_rx_barrier(msg)) {
342 if (priv->enable_tx_path) {
343 int err = priv->enable_tx_path(priv);
349 /* wake network queue up (echo_skb array is empty) */
350 netif_wake_queue(ndev);
355 skb = alloc_can_err_skb(ndev, &cf);
357 /* test state error bits according to their priority */
358 if (pucan_status_is_busoff(msg)) {
359 netdev_dbg(ndev, "Bus-off entry status\n");
360 priv->can.state = CAN_STATE_BUS_OFF;
361 priv->can.can_stats.bus_off++;
364 cf->can_id |= CAN_ERR_BUSOFF;
366 } else if (pucan_status_is_passive(msg)) {
367 netdev_dbg(ndev, "Error passive status\n");
368 priv->can.state = CAN_STATE_ERROR_PASSIVE;
369 priv->can.can_stats.error_passive++;
371 cf->can_id |= CAN_ERR_CRTL;
372 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
373 CAN_ERR_CRTL_TX_PASSIVE :
374 CAN_ERR_CRTL_RX_PASSIVE;
375 cf->data[6] = priv->bec.txerr;
376 cf->data[7] = priv->bec.rxerr;
379 } else if (pucan_status_is_warning(msg)) {
380 netdev_dbg(ndev, "Error warning status\n");
381 priv->can.state = CAN_STATE_ERROR_WARNING;
382 priv->can.can_stats.error_warning++;
384 cf->can_id |= CAN_ERR_CRTL;
385 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
386 CAN_ERR_CRTL_TX_WARNING :
387 CAN_ERR_CRTL_RX_WARNING;
388 cf->data[6] = priv->bec.txerr;
389 cf->data[7] = priv->bec.rxerr;
392 } else if (priv->can.state != CAN_STATE_ERROR_ACTIVE) {
393 /* back to ERROR_ACTIVE */
394 netdev_dbg(ndev, "Error active status\n");
395 can_change_state(ndev, cf, CAN_STATE_ERROR_ACTIVE,
396 CAN_STATE_ERROR_ACTIVE);
408 stats->rx_bytes += cf->can_dlc;
414 /* handle uCAN Rx overflow notification */
415 static int pucan_handle_cache_critical(struct peak_canfd_priv *priv)
417 struct net_device_stats *stats = &priv->ndev->stats;
418 struct can_frame *cf;
421 stats->rx_over_errors++;
424 skb = alloc_can_err_skb(priv->ndev, &cf);
430 cf->can_id |= CAN_ERR_CRTL;
431 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
433 cf->data[6] = priv->bec.txerr;
434 cf->data[7] = priv->bec.rxerr;
436 stats->rx_bytes += cf->can_dlc;
443 /* handle a single uCAN message */
444 int peak_canfd_handle_msg(struct peak_canfd_priv *priv,
445 struct pucan_rx_msg *msg)
447 u16 msg_type = le16_to_cpu(msg->type);
448 int msg_size = le16_to_cpu(msg->size);
451 if (!msg_size || !msg_type) {
452 /* null packet found: end of list */
457 case PUCAN_MSG_CAN_RX:
458 err = pucan_handle_can_rx(priv, (struct pucan_rx_msg *)msg);
460 case PUCAN_MSG_ERROR:
461 err = pucan_handle_error(priv, (struct pucan_error_msg *)msg);
463 case PUCAN_MSG_STATUS:
464 err = pucan_handle_status(priv, (struct pucan_status_msg *)msg);
466 case PUCAN_MSG_CACHE_CRITICAL:
467 err = pucan_handle_cache_critical(priv);
480 /* handle a list of rx_count messages from rx_msg memory address */
481 int peak_canfd_handle_msgs_list(struct peak_canfd_priv *priv,
482 struct pucan_rx_msg *msg_list, int msg_count)
484 void *msg_ptr = msg_list;
487 for (i = 0; i < msg_count; i++) {
488 msg_size = peak_canfd_handle_msg(priv, msg_ptr);
490 /* a null packet can be found at the end of a list */
503 static int peak_canfd_start(struct peak_canfd_priv *priv)
507 err = pucan_clr_err_counters(priv);
516 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
517 err = pucan_set_listen_only_mode(priv);
519 err = pucan_set_normal_mode(priv);
525 static void peak_canfd_stop(struct peak_canfd_priv *priv)
529 /* go back to RESET mode */
530 err = pucan_set_reset_mode(priv);
532 netdev_err(priv->ndev, "channel %u reset failed\n",
535 /* abort last Tx (MUST be done in RESET mode only!) */
536 pucan_tx_abort(priv, PUCAN_TX_ABORT_FLUSH);
540 static int peak_canfd_set_mode(struct net_device *ndev, enum can_mode mode)
542 struct peak_canfd_priv *priv = netdev_priv(ndev);
546 peak_canfd_start(priv);
547 netif_wake_queue(ndev);
556 static int peak_canfd_get_berr_counter(const struct net_device *ndev,
557 struct can_berr_counter *bec)
559 struct peak_canfd_priv *priv = netdev_priv(ndev);
565 static int peak_canfd_open(struct net_device *ndev)
567 struct peak_canfd_priv *priv = netdev_priv(ndev);
570 err = open_candev(ndev);
572 netdev_err(ndev, "open_candev() failed, error %d\n", err);
576 err = pucan_set_reset_mode(priv);
580 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
581 if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
582 err = pucan_clr_options(priv, PUCAN_OPTION_CANDFDISO);
584 err = pucan_set_options(priv, PUCAN_OPTION_CANDFDISO);
590 /* set option: get rx/tx error counters */
591 err = pucan_set_options(priv, PUCAN_OPTION_ERROR);
595 /* accept all standard CAN ID */
596 for (i = 0; i <= PUCAN_FLTSTD_ROW_IDX_MAX; i++)
597 pucan_set_std_filter(priv, i, 0xffffffff);
599 err = peak_canfd_start(priv);
603 /* receiving the RB status says when Tx path is ready */
604 err = pucan_setup_rx_barrier(priv);
614 static int peak_canfd_set_bittiming(struct net_device *ndev)
616 struct peak_canfd_priv *priv = netdev_priv(ndev);
618 return pucan_set_timing_slow(priv, &priv->can.bittiming);
621 static int peak_canfd_set_data_bittiming(struct net_device *ndev)
623 struct peak_canfd_priv *priv = netdev_priv(ndev);
625 return pucan_set_timing_fast(priv, &priv->can.data_bittiming);
628 static int peak_canfd_close(struct net_device *ndev)
630 struct peak_canfd_priv *priv = netdev_priv(ndev);
632 netif_stop_queue(ndev);
633 peak_canfd_stop(priv);
639 static netdev_tx_t peak_canfd_start_xmit(struct sk_buff *skb,
640 struct net_device *ndev)
642 struct peak_canfd_priv *priv = netdev_priv(ndev);
643 struct net_device_stats *stats = &ndev->stats;
644 struct canfd_frame *cf = (struct canfd_frame *)skb->data;
645 struct pucan_tx_msg *msg;
646 u16 msg_size, msg_flags;
648 bool should_stop_tx_queue;
652 if (can_dropped_invalid_skb(ndev, skb))
655 msg_size = ALIGN(sizeof(*msg) + cf->len, 4);
656 msg = priv->alloc_tx_msg(priv, msg_size, &room_left);
658 /* should never happen except under bus-off condition and (auto-)restart
663 netif_stop_queue(ndev);
664 return NETDEV_TX_BUSY;
667 msg->size = cpu_to_le16(msg_size);
668 msg->type = cpu_to_le16(PUCAN_MSG_CAN_TX);
671 if (cf->can_id & CAN_EFF_FLAG) {
672 msg_flags |= PUCAN_MSG_EXT_ID;
673 msg->can_id = cpu_to_le32(cf->can_id & CAN_EFF_MASK);
675 msg->can_id = cpu_to_le32(cf->can_id & CAN_SFF_MASK);
678 if (can_is_canfd_skb(skb)) {
679 /* CAN FD frame format */
680 can_dlc = can_len2dlc(cf->len);
682 msg_flags |= PUCAN_MSG_EXT_DATA_LEN;
684 if (cf->flags & CANFD_BRS)
685 msg_flags |= PUCAN_MSG_BITRATE_SWITCH;
687 if (cf->flags & CANFD_ESI)
688 msg_flags |= PUCAN_MSG_ERROR_STATE_IND;
690 /* CAN 2.0 frame format */
693 if (cf->can_id & CAN_RTR_FLAG)
694 msg_flags |= PUCAN_MSG_RTR;
697 /* always ask loopback for echo management */
698 msg_flags |= PUCAN_MSG_LOOPED_BACK;
700 /* set driver specific bit to differentiate with application loopback */
701 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
702 msg_flags |= PUCAN_MSG_SELF_RECEIVE;
704 msg->flags = cpu_to_le16(msg_flags);
705 msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(priv->index, can_dlc);
706 memcpy(msg->d, cf->data, cf->len);
708 /* struct msg client field is used as an index in the echo skbs ring */
709 msg->client = priv->echo_idx;
711 spin_lock_irqsave(&priv->echo_lock, flags);
713 /* prepare and save echo skb in internal slot */
714 can_put_echo_skb(skb, ndev, priv->echo_idx);
716 /* move echo index to the next slot */
717 priv->echo_idx = (priv->echo_idx + 1) % priv->can.echo_skb_max;
719 /* if next slot is not free, stop network queue (no slot free in echo
720 * skb ring means that the controller did not write these frames on
721 * the bus: no need to continue).
723 should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]);
725 /* stop network tx queue if not enough room to save one more msg too */
726 if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
727 should_stop_tx_queue |= (room_left <
728 (sizeof(*msg) + CANFD_MAX_DLEN));
730 should_stop_tx_queue |= (room_left <
731 (sizeof(*msg) + CAN_MAX_DLEN));
733 if (should_stop_tx_queue)
734 netif_stop_queue(ndev);
736 spin_unlock_irqrestore(&priv->echo_lock, flags);
738 /* write the skb on the interface */
739 priv->write_tx_msg(priv, msg);
744 static const struct net_device_ops peak_canfd_netdev_ops = {
745 .ndo_open = peak_canfd_open,
746 .ndo_stop = peak_canfd_close,
747 .ndo_start_xmit = peak_canfd_start_xmit,
748 .ndo_change_mtu = can_change_mtu,
751 struct net_device *alloc_peak_canfd_dev(int sizeof_priv, int index,
754 struct net_device *ndev;
755 struct peak_canfd_priv *priv;
757 /* we DO support local echo */
758 if (echo_skb_max < 0)
759 echo_skb_max = PCANFD_ECHO_SKB_MAX;
761 /* allocate the candev object */
762 ndev = alloc_candev(sizeof_priv, echo_skb_max);
766 priv = netdev_priv(ndev);
768 /* complete now socket-can initialization side */
769 priv->can.state = CAN_STATE_STOPPED;
770 priv->can.bittiming_const = &peak_canfd_nominal_const;
771 priv->can.data_bittiming_const = &peak_canfd_data_const;
773 priv->can.do_set_mode = peak_canfd_set_mode;
774 priv->can.do_get_berr_counter = peak_canfd_get_berr_counter;
775 priv->can.do_set_bittiming = peak_canfd_set_bittiming;
776 priv->can.do_set_data_bittiming = peak_canfd_set_data_bittiming;
777 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
778 CAN_CTRLMODE_LISTENONLY |
779 CAN_CTRLMODE_3_SAMPLES |
781 CAN_CTRLMODE_FD_NON_ISO |
782 CAN_CTRLMODE_BERR_REPORTING;
787 spin_lock_init(&priv->echo_lock);
789 ndev->flags |= IFF_ECHO;
790 ndev->netdev_ops = &peak_canfd_netdev_ops;
791 ndev->dev_id = index;