1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
4 * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>
6 * Copyright (C) 2016 PEAK System-Technik GmbH
10 #include <linux/can/dev.h>
12 #include "peak_canfd_user.h"
14 /* internal IP core cache size (used as default echo skbs max number) */
15 #define PCANFD_ECHO_SKB_MAX 24
17 /* bittiming ranges of the PEAK-System PC CAN-FD interfaces */
18 static const struct can_bittiming_const peak_canfd_nominal_const = {
21 .tseg1_max = (1 << PUCAN_TSLOW_TSGEG1_BITS),
23 .tseg2_max = (1 << PUCAN_TSLOW_TSGEG2_BITS),
24 .sjw_max = (1 << PUCAN_TSLOW_SJW_BITS),
26 .brp_max = (1 << PUCAN_TSLOW_BRP_BITS),
30 static const struct can_bittiming_const peak_canfd_data_const = {
33 .tseg1_max = (1 << PUCAN_TFAST_TSGEG1_BITS),
35 .tseg2_max = (1 << PUCAN_TFAST_TSGEG2_BITS),
36 .sjw_max = (1 << PUCAN_TFAST_SJW_BITS),
38 .brp_max = (1 << PUCAN_TFAST_BRP_BITS),
42 static struct peak_canfd_priv *pucan_init_cmd(struct peak_canfd_priv *priv)
48 static void *pucan_add_cmd(struct peak_canfd_priv *priv, int cmd_op)
50 struct pucan_command *cmd;
52 if (priv->cmd_len + sizeof(*cmd) > priv->cmd_maxlen)
55 cmd = priv->cmd_buffer + priv->cmd_len;
57 /* reset all unused bit to default */
58 memset(cmd, 0, sizeof(*cmd));
60 cmd->opcode_channel = pucan_cmd_opcode_channel(priv->index, cmd_op);
61 priv->cmd_len += sizeof(*cmd);
66 static int pucan_write_cmd(struct peak_canfd_priv *priv)
71 err = priv->pre_cmd(priv);
76 err = priv->write_cmd(priv);
81 err = priv->post_cmd(priv);
86 /* uCAN commands interface functions */
87 static int pucan_set_reset_mode(struct peak_canfd_priv *priv)
89 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RESET_MODE);
90 return pucan_write_cmd(priv);
93 static int pucan_set_normal_mode(struct peak_canfd_priv *priv)
97 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_NORMAL_MODE);
98 err = pucan_write_cmd(priv);
100 priv->can.state = CAN_STATE_ERROR_ACTIVE;
105 static int pucan_set_listen_only_mode(struct peak_canfd_priv *priv)
109 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_LISTEN_ONLY_MODE);
110 err = pucan_write_cmd(priv);
112 priv->can.state = CAN_STATE_ERROR_ACTIVE;
117 static int pucan_set_timing_slow(struct peak_canfd_priv *priv,
118 const struct can_bittiming *pbt)
120 struct pucan_timing_slow *cmd;
122 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_SLOW);
124 cmd->sjw_t = PUCAN_TSLOW_SJW_T(pbt->sjw - 1,
125 priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES);
126 cmd->tseg1 = PUCAN_TSLOW_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1);
127 cmd->tseg2 = PUCAN_TSLOW_TSEG2(pbt->phase_seg2 - 1);
128 cmd->brp = cpu_to_le16(PUCAN_TSLOW_BRP(pbt->brp - 1));
130 cmd->ewl = 96; /* default */
132 netdev_dbg(priv->ndev,
133 "nominal: brp=%u tseg1=%u tseg2=%u sjw=%u\n",
134 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw_t);
136 return pucan_write_cmd(priv);
139 static int pucan_set_timing_fast(struct peak_canfd_priv *priv,
140 const struct can_bittiming *pbt)
142 struct pucan_timing_fast *cmd;
144 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_FAST);
146 cmd->sjw = PUCAN_TFAST_SJW(pbt->sjw - 1);
147 cmd->tseg1 = PUCAN_TFAST_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1);
148 cmd->tseg2 = PUCAN_TFAST_TSEG2(pbt->phase_seg2 - 1);
149 cmd->brp = cpu_to_le16(PUCAN_TFAST_BRP(pbt->brp - 1));
151 netdev_dbg(priv->ndev,
152 "data: brp=%u tseg1=%u tseg2=%u sjw=%u\n",
153 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw);
155 return pucan_write_cmd(priv);
158 static int pucan_set_std_filter(struct peak_canfd_priv *priv, u8 row, u32 mask)
160 struct pucan_std_filter *cmd;
162 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_STD_FILTER);
164 /* all the 11-bits CAN ID values are represented by one bit in a
165 * 64 rows array of 32 bits: the upper 6 bits of the CAN ID select the
166 * row while the lowest 5 bits select the bit in that row.
176 /* set/unset bits in the row */
177 cmd->mask = cpu_to_le32(mask);
179 return pucan_write_cmd(priv);
182 static int pucan_tx_abort(struct peak_canfd_priv *priv, u16 flags)
184 struct pucan_tx_abort *cmd;
186 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TX_ABORT);
188 cmd->flags = cpu_to_le16(flags);
190 return pucan_write_cmd(priv);
193 static int pucan_clr_err_counters(struct peak_canfd_priv *priv)
195 struct pucan_wr_err_cnt *cmd;
197 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_WR_ERR_CNT);
199 cmd->sel_mask = cpu_to_le16(PUCAN_WRERRCNT_TE | PUCAN_WRERRCNT_RE);
203 return pucan_write_cmd(priv);
206 static int pucan_set_options(struct peak_canfd_priv *priv, u16 opt_mask)
208 struct pucan_options *cmd;
210 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_EN_OPTION);
212 cmd->options = cpu_to_le16(opt_mask);
214 return pucan_write_cmd(priv);
217 static int pucan_clr_options(struct peak_canfd_priv *priv, u16 opt_mask)
219 struct pucan_options *cmd;
221 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_CLR_DIS_OPTION);
223 cmd->options = cpu_to_le16(opt_mask);
225 return pucan_write_cmd(priv);
228 static int pucan_setup_rx_barrier(struct peak_canfd_priv *priv)
230 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RX_BARRIER);
232 return pucan_write_cmd(priv);
235 /* handle the reception of one CAN frame */
236 static int pucan_handle_can_rx(struct peak_canfd_priv *priv,
237 struct pucan_rx_msg *msg)
239 struct net_device_stats *stats = &priv->ndev->stats;
240 struct canfd_frame *cf;
242 const u16 rx_msg_flags = le16_to_cpu(msg->flags);
245 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN)
246 cf_len = can_dlc2len(get_canfd_dlc(pucan_msg_get_dlc(msg)));
248 cf_len = get_can_dlc(pucan_msg_get_dlc(msg));
250 /* if this frame is an echo, */
251 if ((rx_msg_flags & PUCAN_MSG_LOOPED_BACK) &&
252 !(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE)) {
255 spin_lock_irqsave(&priv->echo_lock, flags);
256 can_get_echo_skb(priv->ndev, msg->client);
258 /* count bytes of the echo instead of skb */
259 stats->tx_bytes += cf_len;
262 /* restart tx queue (a slot is free) */
263 netif_wake_queue(priv->ndev);
265 spin_unlock_irqrestore(&priv->echo_lock, flags);
269 /* otherwise, it should be pushed into rx fifo */
270 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) {
271 /* CANFD frame case */
272 skb = alloc_canfd_skb(priv->ndev, &cf);
276 if (rx_msg_flags & PUCAN_MSG_BITRATE_SWITCH)
277 cf->flags |= CANFD_BRS;
279 if (rx_msg_flags & PUCAN_MSG_ERROR_STATE_IND)
280 cf->flags |= CANFD_ESI;
282 /* CAN 2.0 frame case */
283 skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cf);
288 cf->can_id = le32_to_cpu(msg->can_id);
291 if (rx_msg_flags & PUCAN_MSG_EXT_ID)
292 cf->can_id |= CAN_EFF_FLAG;
294 if (rx_msg_flags & PUCAN_MSG_RTR)
295 cf->can_id |= CAN_RTR_FLAG;
297 memcpy(cf->data, msg->d, cf->len);
299 stats->rx_bytes += cf->len;
307 /* handle rx/tx error counters notification */
308 static int pucan_handle_error(struct peak_canfd_priv *priv,
309 struct pucan_error_msg *msg)
311 priv->bec.txerr = msg->tx_err_cnt;
312 priv->bec.rxerr = msg->rx_err_cnt;
317 /* handle status notification */
318 static int pucan_handle_status(struct peak_canfd_priv *priv,
319 struct pucan_status_msg *msg)
321 struct net_device *ndev = priv->ndev;
322 struct net_device_stats *stats = &ndev->stats;
323 struct can_frame *cf;
326 /* this STATUS is the CNF of the RX_BARRIER: Tx path can be setup */
327 if (pucan_status_is_rx_barrier(msg)) {
329 if (priv->enable_tx_path) {
330 int err = priv->enable_tx_path(priv);
336 /* start network queue (echo_skb array is empty) */
337 netif_start_queue(ndev);
342 skb = alloc_can_err_skb(ndev, &cf);
344 /* test state error bits according to their priority */
345 if (pucan_status_is_busoff(msg)) {
346 netdev_dbg(ndev, "Bus-off entry status\n");
347 priv->can.state = CAN_STATE_BUS_OFF;
348 priv->can.can_stats.bus_off++;
351 cf->can_id |= CAN_ERR_BUSOFF;
353 } else if (pucan_status_is_passive(msg)) {
354 netdev_dbg(ndev, "Error passive status\n");
355 priv->can.state = CAN_STATE_ERROR_PASSIVE;
356 priv->can.can_stats.error_passive++;
358 cf->can_id |= CAN_ERR_CRTL;
359 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
360 CAN_ERR_CRTL_TX_PASSIVE :
361 CAN_ERR_CRTL_RX_PASSIVE;
362 cf->data[6] = priv->bec.txerr;
363 cf->data[7] = priv->bec.rxerr;
366 } else if (pucan_status_is_warning(msg)) {
367 netdev_dbg(ndev, "Error warning status\n");
368 priv->can.state = CAN_STATE_ERROR_WARNING;
369 priv->can.can_stats.error_warning++;
371 cf->can_id |= CAN_ERR_CRTL;
372 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ?
373 CAN_ERR_CRTL_TX_WARNING :
374 CAN_ERR_CRTL_RX_WARNING;
375 cf->data[6] = priv->bec.txerr;
376 cf->data[7] = priv->bec.rxerr;
379 } else if (priv->can.state != CAN_STATE_ERROR_ACTIVE) {
380 /* back to ERROR_ACTIVE */
381 netdev_dbg(ndev, "Error active status\n");
382 can_change_state(ndev, cf, CAN_STATE_ERROR_ACTIVE,
383 CAN_STATE_ERROR_ACTIVE);
395 stats->rx_bytes += cf->can_dlc;
401 /* handle uCAN Rx overflow notification */
402 static int pucan_handle_cache_critical(struct peak_canfd_priv *priv)
404 struct net_device_stats *stats = &priv->ndev->stats;
405 struct can_frame *cf;
408 stats->rx_over_errors++;
411 skb = alloc_can_err_skb(priv->ndev, &cf);
417 cf->can_id |= CAN_ERR_CRTL;
418 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
420 cf->data[6] = priv->bec.txerr;
421 cf->data[7] = priv->bec.rxerr;
423 stats->rx_bytes += cf->can_dlc;
430 /* handle a single uCAN message */
431 int peak_canfd_handle_msg(struct peak_canfd_priv *priv,
432 struct pucan_rx_msg *msg)
434 u16 msg_type = le16_to_cpu(msg->type);
435 int msg_size = le16_to_cpu(msg->size);
438 if (!msg_size || !msg_type) {
439 /* null packet found: end of list */
444 case PUCAN_MSG_CAN_RX:
445 err = pucan_handle_can_rx(priv, (struct pucan_rx_msg *)msg);
447 case PUCAN_MSG_ERROR:
448 err = pucan_handle_error(priv, (struct pucan_error_msg *)msg);
450 case PUCAN_MSG_STATUS:
451 err = pucan_handle_status(priv, (struct pucan_status_msg *)msg);
453 case PUCAN_MSG_CACHE_CRITICAL:
454 err = pucan_handle_cache_critical(priv);
467 /* handle a list of rx_count messages from rx_msg memory address */
468 int peak_canfd_handle_msgs_list(struct peak_canfd_priv *priv,
469 struct pucan_rx_msg *msg_list, int msg_count)
471 void *msg_ptr = msg_list;
474 for (i = 0; i < msg_count; i++) {
475 msg_size = peak_canfd_handle_msg(priv, msg_ptr);
477 /* a null packet can be found at the end of a list */
481 msg_ptr += ALIGN(msg_size, 4);
490 static int peak_canfd_start(struct peak_canfd_priv *priv)
494 err = pucan_clr_err_counters(priv);
503 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
504 err = pucan_set_listen_only_mode(priv);
506 err = pucan_set_normal_mode(priv);
512 static void peak_canfd_stop(struct peak_canfd_priv *priv)
516 /* go back to RESET mode */
517 err = pucan_set_reset_mode(priv);
519 netdev_err(priv->ndev, "channel %u reset failed\n",
522 /* abort last Tx (MUST be done in RESET mode only!) */
523 pucan_tx_abort(priv, PUCAN_TX_ABORT_FLUSH);
527 static int peak_canfd_set_mode(struct net_device *ndev, enum can_mode mode)
529 struct peak_canfd_priv *priv = netdev_priv(ndev);
533 peak_canfd_start(priv);
534 netif_wake_queue(ndev);
543 static int peak_canfd_get_berr_counter(const struct net_device *ndev,
544 struct can_berr_counter *bec)
546 struct peak_canfd_priv *priv = netdev_priv(ndev);
552 static int peak_canfd_open(struct net_device *ndev)
554 struct peak_canfd_priv *priv = netdev_priv(ndev);
557 err = open_candev(ndev);
559 netdev_err(ndev, "open_candev() failed, error %d\n", err);
563 err = pucan_set_reset_mode(priv);
567 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
568 if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
569 err = pucan_clr_options(priv, PUCAN_OPTION_CANDFDISO);
571 err = pucan_set_options(priv, PUCAN_OPTION_CANDFDISO);
577 /* set option: get rx/tx error counters */
578 err = pucan_set_options(priv, PUCAN_OPTION_ERROR);
582 /* accept all standard CAN ID */
583 for (i = 0; i <= PUCAN_FLTSTD_ROW_IDX_MAX; i++)
584 pucan_set_std_filter(priv, i, 0xffffffff);
586 err = peak_canfd_start(priv);
590 /* receiving the RB status says when Tx path is ready */
591 err = pucan_setup_rx_barrier(priv);
601 static int peak_canfd_set_bittiming(struct net_device *ndev)
603 struct peak_canfd_priv *priv = netdev_priv(ndev);
605 return pucan_set_timing_slow(priv, &priv->can.bittiming);
608 static int peak_canfd_set_data_bittiming(struct net_device *ndev)
610 struct peak_canfd_priv *priv = netdev_priv(ndev);
612 return pucan_set_timing_fast(priv, &priv->can.data_bittiming);
615 static int peak_canfd_close(struct net_device *ndev)
617 struct peak_canfd_priv *priv = netdev_priv(ndev);
619 netif_stop_queue(ndev);
620 peak_canfd_stop(priv);
626 static netdev_tx_t peak_canfd_start_xmit(struct sk_buff *skb,
627 struct net_device *ndev)
629 struct peak_canfd_priv *priv = netdev_priv(ndev);
630 struct net_device_stats *stats = &ndev->stats;
631 struct canfd_frame *cf = (struct canfd_frame *)skb->data;
632 struct pucan_tx_msg *msg;
633 u16 msg_size, msg_flags;
635 bool should_stop_tx_queue;
639 if (can_dropped_invalid_skb(ndev, skb))
642 msg_size = ALIGN(sizeof(*msg) + cf->len, 4);
643 msg = priv->alloc_tx_msg(priv, msg_size, &room_left);
645 /* should never happen except under bus-off condition and (auto-)restart
650 netif_stop_queue(ndev);
651 return NETDEV_TX_BUSY;
654 msg->size = cpu_to_le16(msg_size);
655 msg->type = cpu_to_le16(PUCAN_MSG_CAN_TX);
658 if (cf->can_id & CAN_EFF_FLAG) {
659 msg_flags |= PUCAN_MSG_EXT_ID;
660 msg->can_id = cpu_to_le32(cf->can_id & CAN_EFF_MASK);
662 msg->can_id = cpu_to_le32(cf->can_id & CAN_SFF_MASK);
665 if (can_is_canfd_skb(skb)) {
666 /* CAN FD frame format */
667 can_dlc = can_len2dlc(cf->len);
669 msg_flags |= PUCAN_MSG_EXT_DATA_LEN;
671 if (cf->flags & CANFD_BRS)
672 msg_flags |= PUCAN_MSG_BITRATE_SWITCH;
674 if (cf->flags & CANFD_ESI)
675 msg_flags |= PUCAN_MSG_ERROR_STATE_IND;
677 /* CAN 2.0 frame format */
680 if (cf->can_id & CAN_RTR_FLAG)
681 msg_flags |= PUCAN_MSG_RTR;
684 /* always ask loopback for echo management */
685 msg_flags |= PUCAN_MSG_LOOPED_BACK;
687 /* set driver specific bit to differentiate with application loopback */
688 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
689 msg_flags |= PUCAN_MSG_SELF_RECEIVE;
691 msg->flags = cpu_to_le16(msg_flags);
692 msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(priv->index, can_dlc);
693 memcpy(msg->d, cf->data, cf->len);
695 /* struct msg client field is used as an index in the echo skbs ring */
696 msg->client = priv->echo_idx;
698 spin_lock_irqsave(&priv->echo_lock, flags);
700 /* prepare and save echo skb in internal slot */
701 can_put_echo_skb(skb, ndev, priv->echo_idx);
703 /* move echo index to the next slot */
704 priv->echo_idx = (priv->echo_idx + 1) % priv->can.echo_skb_max;
706 /* if next slot is not free, stop network queue (no slot free in echo
707 * skb ring means that the controller did not write these frames on
708 * the bus: no need to continue).
710 should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]);
712 /* stop network tx queue if not enough room to save one more msg too */
713 if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
714 should_stop_tx_queue |= (room_left <
715 (sizeof(*msg) + CANFD_MAX_DLEN));
717 should_stop_tx_queue |= (room_left <
718 (sizeof(*msg) + CAN_MAX_DLEN));
720 if (should_stop_tx_queue)
721 netif_stop_queue(ndev);
723 spin_unlock_irqrestore(&priv->echo_lock, flags);
725 /* write the skb on the interface */
726 priv->write_tx_msg(priv, msg);
731 static const struct net_device_ops peak_canfd_netdev_ops = {
732 .ndo_open = peak_canfd_open,
733 .ndo_stop = peak_canfd_close,
734 .ndo_start_xmit = peak_canfd_start_xmit,
735 .ndo_change_mtu = can_change_mtu,
738 struct net_device *alloc_peak_canfd_dev(int sizeof_priv, int index,
741 struct net_device *ndev;
742 struct peak_canfd_priv *priv;
744 /* we DO support local echo */
745 if (echo_skb_max < 0)
746 echo_skb_max = PCANFD_ECHO_SKB_MAX;
748 /* allocate the candev object */
749 ndev = alloc_candev(sizeof_priv, echo_skb_max);
753 priv = netdev_priv(ndev);
755 /* complete now socket-can initialization side */
756 priv->can.state = CAN_STATE_STOPPED;
757 priv->can.bittiming_const = &peak_canfd_nominal_const;
758 priv->can.data_bittiming_const = &peak_canfd_data_const;
760 priv->can.do_set_mode = peak_canfd_set_mode;
761 priv->can.do_get_berr_counter = peak_canfd_get_berr_counter;
762 priv->can.do_set_bittiming = peak_canfd_set_bittiming;
763 priv->can.do_set_data_bittiming = peak_canfd_set_data_bittiming;
764 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
765 CAN_CTRLMODE_LISTENONLY |
766 CAN_CTRLMODE_3_SAMPLES |
768 CAN_CTRLMODE_FD_NON_ISO |
769 CAN_CTRLMODE_BERR_REPORTING;
774 spin_lock_init(&priv->echo_lock);
776 ndev->flags |= IFF_ECHO;
777 ndev->netdev_ops = &peak_canfd_netdev_ops;
778 ndev->dev_id = index;