cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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es58x_fd.c (17890B)


      1// SPDX-License-Identifier: GPL-2.0
      2
      3/* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces.
      4 *
      5 * File es58x_fd.c: Adds support to ETAS ES582.1 and ES584.1 (naming
      6 * convention: we use the term "ES58X FD" when referring to those two
      7 * variants together).
      8 *
      9 * Copyright (c) 2019 Robert Bosch Engineering and Business Solutions. All rights reserved.
     10 * Copyright (c) 2020 ETAS K.K.. All rights reserved.
     11 * Copyright (c) 2020, 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
     12 */
     13
     14#include <linux/kernel.h>
     15#include <linux/units.h>
     16#include <asm/unaligned.h>
     17
     18#include "es58x_core.h"
     19#include "es58x_fd.h"
     20
     21/**
     22 * es58x_fd_sizeof_rx_tx_msg() - Calculate the actual length of the
     23 *	structure of a rx or tx message.
     24 * @msg: message of variable length, must have a dlc and a len fields.
     25 *
     26 * Even if RTR frames have actually no payload, the ES58X devices
     27 * still expect it. Must be a macro in order to accept several types
     28 * (struct es58x_fd_tx_can_msg and struct es58x_fd_rx_can_msg) as an
     29 * input.
     30 *
     31 * Return: length of the message.
     32 */
     33#define es58x_fd_sizeof_rx_tx_msg(msg)					\
     34({									\
     35	typeof(msg) __msg = (msg);					\
     36	size_t __msg_len;						\
     37									\
     38	if (__msg.flags & ES58X_FLAG_FD_DATA)				\
     39		__msg_len = canfd_sanitize_len(__msg.len);		\
     40	else								\
     41		__msg_len = can_cc_dlc2len(__msg.dlc);			\
     42									\
     43	offsetof(typeof(__msg), data[__msg_len]);			\
     44})
     45
     46static enum es58x_fd_cmd_type es58x_fd_cmd_type(struct net_device *netdev)
     47{
     48	u32 ctrlmode = es58x_priv(netdev)->can.ctrlmode;
     49
     50	if (ctrlmode & (CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO))
     51		return ES58X_FD_CMD_TYPE_CANFD;
     52	else
     53		return ES58X_FD_CMD_TYPE_CAN;
     54}
     55
     56static u16 es58x_fd_get_msg_len(const union es58x_urb_cmd *urb_cmd)
     57{
     58	return get_unaligned_le16(&urb_cmd->es58x_fd_urb_cmd.msg_len);
     59}
     60
     61static int es58x_fd_echo_msg(struct net_device *netdev,
     62			     const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
     63{
     64	struct es58x_priv *priv = es58x_priv(netdev);
     65	const struct es58x_fd_echo_msg *echo_msg;
     66	struct es58x_device *es58x_dev = priv->es58x_dev;
     67	u64 *tstamps = es58x_dev->timestamps;
     68	u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
     69	int i, num_element;
     70	u32 rcv_packet_idx;
     71
     72	const u32 mask = GENMASK(BITS_PER_TYPE(mask) - 1,
     73				 BITS_PER_TYPE(echo_msg->packet_idx));
     74
     75	num_element = es58x_msg_num_element(es58x_dev->dev,
     76					    es58x_fd_urb_cmd->echo_msg,
     77					    msg_len);
     78	if (num_element < 0)
     79		return num_element;
     80	echo_msg = es58x_fd_urb_cmd->echo_msg;
     81
     82	rcv_packet_idx = (priv->tx_tail & mask) | echo_msg[0].packet_idx;
     83	for (i = 0; i < num_element; i++) {
     84		if ((u8)rcv_packet_idx != echo_msg[i].packet_idx) {
     85			netdev_err(netdev, "Packet idx jumped from %u to %u\n",
     86				   (u8)rcv_packet_idx - 1,
     87				   echo_msg[i].packet_idx);
     88			return -EBADMSG;
     89		}
     90
     91		tstamps[i] = get_unaligned_le64(&echo_msg[i].timestamp);
     92		rcv_packet_idx++;
     93	}
     94
     95	return es58x_can_get_echo_skb(netdev, priv->tx_tail, tstamps, num_element);
     96}
     97
     98static int es58x_fd_rx_can_msg(struct net_device *netdev,
     99			       const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
    100{
    101	struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
    102	const u8 *rx_can_msg_buf = es58x_fd_urb_cmd->rx_can_msg_buf;
    103	u16 rx_can_msg_buf_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
    104	int pkts, ret;
    105
    106	ret = es58x_check_msg_max_len(es58x_dev->dev,
    107				      es58x_fd_urb_cmd->rx_can_msg_buf,
    108				      rx_can_msg_buf_len);
    109	if (ret)
    110		return ret;
    111
    112	for (pkts = 0; rx_can_msg_buf_len > 0; pkts++) {
    113		const struct es58x_fd_rx_can_msg *rx_can_msg =
    114		    (const struct es58x_fd_rx_can_msg *)rx_can_msg_buf;
    115		bool is_can_fd = !!(rx_can_msg->flags & ES58X_FLAG_FD_DATA);
    116		/* rx_can_msg_len is the length of the rx_can_msg
    117		 * buffer. Not to be confused with rx_can_msg->len
    118		 * which is the length of the CAN payload
    119		 * rx_can_msg->data.
    120		 */
    121		u16 rx_can_msg_len = es58x_fd_sizeof_rx_tx_msg(*rx_can_msg);
    122
    123		if (rx_can_msg_len > rx_can_msg_buf_len) {
    124			netdev_err(netdev,
    125				   "%s: Expected a rx_can_msg of size %d but only %d bytes are left in rx_can_msg_buf\n",
    126				   __func__,
    127				   rx_can_msg_len, rx_can_msg_buf_len);
    128			return -EMSGSIZE;
    129		}
    130		if (rx_can_msg->len > CANFD_MAX_DLEN) {
    131			netdev_err(netdev,
    132				   "%s: Data length is %d but maximum should be %d\n",
    133				   __func__, rx_can_msg->len, CANFD_MAX_DLEN);
    134			return -EMSGSIZE;
    135		}
    136
    137		if (netif_running(netdev)) {
    138			u64 tstamp = get_unaligned_le64(&rx_can_msg->timestamp);
    139			canid_t can_id = get_unaligned_le32(&rx_can_msg->can_id);
    140			u8 dlc;
    141
    142			if (is_can_fd)
    143				dlc = can_fd_len2dlc(rx_can_msg->len);
    144			else
    145				dlc = rx_can_msg->dlc;
    146
    147			ret = es58x_rx_can_msg(netdev, tstamp, rx_can_msg->data,
    148					       can_id, rx_can_msg->flags, dlc);
    149			if (ret)
    150				break;
    151		}
    152
    153		rx_can_msg_buf_len -= rx_can_msg_len;
    154		rx_can_msg_buf += rx_can_msg_len;
    155	}
    156
    157	if (!netif_running(netdev)) {
    158		if (net_ratelimit())
    159			netdev_info(netdev,
    160				    "%s: %s is down, dropping %d rx packets\n",
    161				    __func__, netdev->name, pkts);
    162		netdev->stats.rx_dropped += pkts;
    163	}
    164
    165	return ret;
    166}
    167
    168static int es58x_fd_rx_event_msg(struct net_device *netdev,
    169				 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
    170{
    171	struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
    172	u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
    173	const struct es58x_fd_rx_event_msg *rx_event_msg;
    174	int ret;
    175
    176	rx_event_msg = &es58x_fd_urb_cmd->rx_event_msg;
    177	ret = es58x_check_msg_len(es58x_dev->dev, *rx_event_msg, msg_len);
    178	if (ret)
    179		return ret;
    180
    181	return es58x_rx_err_msg(netdev, rx_event_msg->error_code,
    182				rx_event_msg->event_code,
    183				get_unaligned_le64(&rx_event_msg->timestamp));
    184}
    185
    186static int es58x_fd_rx_cmd_ret_u32(struct net_device *netdev,
    187				   const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd,
    188				   enum es58x_ret_type cmd_ret_type)
    189{
    190	struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
    191	u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
    192	int ret;
    193
    194	ret = es58x_check_msg_len(es58x_dev->dev,
    195				  es58x_fd_urb_cmd->rx_cmd_ret_le32, msg_len);
    196	if (ret)
    197		return ret;
    198
    199	return es58x_rx_cmd_ret_u32(netdev, cmd_ret_type,
    200				    get_unaligned_le32(&es58x_fd_urb_cmd->rx_cmd_ret_le32));
    201}
    202
    203static int es58x_fd_tx_ack_msg(struct net_device *netdev,
    204			       const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
    205{
    206	struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
    207	const struct es58x_fd_tx_ack_msg *tx_ack_msg;
    208	u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
    209	int ret;
    210
    211	tx_ack_msg = &es58x_fd_urb_cmd->tx_ack_msg;
    212	ret = es58x_check_msg_len(es58x_dev->dev, *tx_ack_msg, msg_len);
    213	if (ret)
    214		return ret;
    215
    216	return es58x_tx_ack_msg(netdev,
    217				get_unaligned_le16(&tx_ack_msg->tx_free_entries),
    218				get_unaligned_le32(&tx_ack_msg->rx_cmd_ret_le32));
    219}
    220
    221static int es58x_fd_can_cmd_id(struct es58x_device *es58x_dev,
    222			       const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
    223{
    224	struct net_device *netdev;
    225	int ret;
    226
    227	ret = es58x_get_netdev(es58x_dev, es58x_fd_urb_cmd->channel_idx,
    228			       ES58X_FD_CHANNEL_IDX_OFFSET, &netdev);
    229	if (ret)
    230		return ret;
    231
    232	switch ((enum es58x_fd_can_cmd_id)es58x_fd_urb_cmd->cmd_id) {
    233	case ES58X_FD_CAN_CMD_ID_ENABLE_CHANNEL:
    234		return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
    235					       ES58X_RET_TYPE_ENABLE_CHANNEL);
    236
    237	case ES58X_FD_CAN_CMD_ID_DISABLE_CHANNEL:
    238		return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
    239					       ES58X_RET_TYPE_DISABLE_CHANNEL);
    240
    241	case ES58X_FD_CAN_CMD_ID_TX_MSG:
    242		return es58x_fd_tx_ack_msg(netdev, es58x_fd_urb_cmd);
    243
    244	case ES58X_FD_CAN_CMD_ID_ECHO_MSG:
    245		return es58x_fd_echo_msg(netdev, es58x_fd_urb_cmd);
    246
    247	case ES58X_FD_CAN_CMD_ID_RX_MSG:
    248		return es58x_fd_rx_can_msg(netdev, es58x_fd_urb_cmd);
    249
    250	case ES58X_FD_CAN_CMD_ID_RESET_RX:
    251		return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
    252					       ES58X_RET_TYPE_RESET_RX);
    253
    254	case ES58X_FD_CAN_CMD_ID_RESET_TX:
    255		return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
    256					       ES58X_RET_TYPE_RESET_TX);
    257
    258	case ES58X_FD_CAN_CMD_ID_ERROR_OR_EVENT_MSG:
    259		return es58x_fd_rx_event_msg(netdev, es58x_fd_urb_cmd);
    260
    261	default:
    262		return -EBADRQC;
    263	}
    264}
    265
    266static int es58x_fd_device_cmd_id(struct es58x_device *es58x_dev,
    267				  const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
    268{
    269	u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
    270	int ret;
    271
    272	switch ((enum es58x_fd_dev_cmd_id)es58x_fd_urb_cmd->cmd_id) {
    273	case ES58X_FD_DEV_CMD_ID_TIMESTAMP:
    274		ret = es58x_check_msg_len(es58x_dev->dev,
    275					  es58x_fd_urb_cmd->timestamp, msg_len);
    276		if (ret)
    277			return ret;
    278		es58x_rx_timestamp(es58x_dev,
    279				   get_unaligned_le64(&es58x_fd_urb_cmd->timestamp));
    280		return 0;
    281
    282	default:
    283		return -EBADRQC;
    284	}
    285}
    286
    287static int es58x_fd_handle_urb_cmd(struct es58x_device *es58x_dev,
    288				   const union es58x_urb_cmd *urb_cmd)
    289{
    290	const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd;
    291	int ret;
    292
    293	es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
    294
    295	switch ((enum es58x_fd_cmd_type)es58x_fd_urb_cmd->cmd_type) {
    296	case ES58X_FD_CMD_TYPE_CAN:
    297	case ES58X_FD_CMD_TYPE_CANFD:
    298		ret = es58x_fd_can_cmd_id(es58x_dev, es58x_fd_urb_cmd);
    299		break;
    300
    301	case ES58X_FD_CMD_TYPE_DEVICE:
    302		ret = es58x_fd_device_cmd_id(es58x_dev, es58x_fd_urb_cmd);
    303		break;
    304
    305	default:
    306		ret = -EBADRQC;
    307		break;
    308	}
    309
    310	if (ret == -EBADRQC)
    311		dev_err(es58x_dev->dev,
    312			"%s: Unknown command type (0x%02X) and command ID (0x%02X) combination\n",
    313			__func__, es58x_fd_urb_cmd->cmd_type,
    314			es58x_fd_urb_cmd->cmd_id);
    315
    316	return ret;
    317}
    318
    319static void es58x_fd_fill_urb_header(union es58x_urb_cmd *urb_cmd, u8 cmd_type,
    320				     u8 cmd_id, u8 channel_idx, u16 msg_len)
    321{
    322	struct es58x_fd_urb_cmd *es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
    323
    324	es58x_fd_urb_cmd->SOF = cpu_to_le16(es58x_fd_param.tx_start_of_frame);
    325	es58x_fd_urb_cmd->cmd_type = cmd_type;
    326	es58x_fd_urb_cmd->cmd_id = cmd_id;
    327	es58x_fd_urb_cmd->channel_idx = channel_idx;
    328	es58x_fd_urb_cmd->msg_len = cpu_to_le16(msg_len);
    329}
    330
    331static int es58x_fd_tx_can_msg(struct es58x_priv *priv,
    332			       const struct sk_buff *skb)
    333{
    334	struct es58x_device *es58x_dev = priv->es58x_dev;
    335	union es58x_urb_cmd *urb_cmd = priv->tx_urb->transfer_buffer;
    336	struct es58x_fd_urb_cmd *es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
    337	struct can_frame *cf = (struct can_frame *)skb->data;
    338	struct es58x_fd_tx_can_msg *tx_can_msg;
    339	bool is_fd = can_is_canfd_skb(skb);
    340	u16 msg_len;
    341	int ret;
    342
    343	if (priv->tx_can_msg_cnt == 0) {
    344		msg_len = 0;
    345		es58x_fd_fill_urb_header(urb_cmd,
    346					 is_fd ? ES58X_FD_CMD_TYPE_CANFD
    347					       : ES58X_FD_CMD_TYPE_CAN,
    348					 ES58X_FD_CAN_CMD_ID_TX_MSG_NO_ACK,
    349					 priv->channel_idx, msg_len);
    350	} else {
    351		msg_len = es58x_fd_get_msg_len(urb_cmd);
    352	}
    353
    354	ret = es58x_check_msg_max_len(es58x_dev->dev,
    355				      es58x_fd_urb_cmd->tx_can_msg_buf,
    356				      msg_len + sizeof(*tx_can_msg));
    357	if (ret)
    358		return ret;
    359
    360	/* Fill message contents. */
    361	tx_can_msg = (typeof(tx_can_msg))&es58x_fd_urb_cmd->raw_msg[msg_len];
    362	tx_can_msg->packet_idx = (u8)priv->tx_head;
    363	put_unaligned_le32(es58x_get_raw_can_id(cf), &tx_can_msg->can_id);
    364	tx_can_msg->flags = (u8)es58x_get_flags(skb);
    365	if (is_fd)
    366		tx_can_msg->len = cf->len;
    367	else
    368		tx_can_msg->dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
    369	memcpy(tx_can_msg->data, cf->data, cf->len);
    370
    371	/* Calculate new sizes */
    372	msg_len += es58x_fd_sizeof_rx_tx_msg(*tx_can_msg);
    373	priv->tx_urb->transfer_buffer_length = es58x_get_urb_cmd_len(es58x_dev,
    374								     msg_len);
    375	put_unaligned_le16(msg_len, &es58x_fd_urb_cmd->msg_len);
    376
    377	return 0;
    378}
    379
    380static void es58x_fd_convert_bittiming(struct es58x_fd_bittiming *es58x_fd_bt,
    381				       struct can_bittiming *bt)
    382{
    383	/* The actual value set in the hardware registers is one less
    384	 * than the functional value.
    385	 */
    386	const int offset = 1;
    387
    388	es58x_fd_bt->bitrate = cpu_to_le32(bt->bitrate);
    389	es58x_fd_bt->tseg1 =
    390	    cpu_to_le16(bt->prop_seg + bt->phase_seg1 - offset);
    391	es58x_fd_bt->tseg2 = cpu_to_le16(bt->phase_seg2 - offset);
    392	es58x_fd_bt->brp = cpu_to_le16(bt->brp - offset);
    393	es58x_fd_bt->sjw = cpu_to_le16(bt->sjw - offset);
    394}
    395
    396static int es58x_fd_enable_channel(struct es58x_priv *priv)
    397{
    398	struct es58x_device *es58x_dev = priv->es58x_dev;
    399	struct net_device *netdev = es58x_dev->netdev[priv->channel_idx];
    400	struct es58x_fd_tx_conf_msg tx_conf_msg = { 0 };
    401	u32 ctrlmode;
    402	size_t conf_len = 0;
    403
    404	es58x_fd_convert_bittiming(&tx_conf_msg.nominal_bittiming,
    405				   &priv->can.bittiming);
    406	ctrlmode = priv->can.ctrlmode;
    407
    408	if (ctrlmode & CAN_CTRLMODE_3_SAMPLES)
    409		tx_conf_msg.samples_per_bit = ES58X_SAMPLES_PER_BIT_THREE;
    410	else
    411		tx_conf_msg.samples_per_bit = ES58X_SAMPLES_PER_BIT_ONE;
    412	tx_conf_msg.sync_edge = ES58X_SYNC_EDGE_SINGLE;
    413	tx_conf_msg.physical_layer = ES58X_PHYSICAL_LAYER_HIGH_SPEED;
    414	tx_conf_msg.echo_mode = ES58X_ECHO_ON;
    415	if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
    416		tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_PASSIVE;
    417	else
    418		tx_conf_msg.ctrlmode |=  ES58X_FD_CTRLMODE_ACTIVE;
    419
    420	if (ctrlmode & CAN_CTRLMODE_FD_NON_ISO) {
    421		tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_FD_NON_ISO;
    422		tx_conf_msg.canfd_enabled = 1;
    423	} else if (ctrlmode & CAN_CTRLMODE_FD) {
    424		tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_FD;
    425		tx_conf_msg.canfd_enabled = 1;
    426	}
    427
    428	if (tx_conf_msg.canfd_enabled) {
    429		es58x_fd_convert_bittiming(&tx_conf_msg.data_bittiming,
    430					   &priv->can.data_bittiming);
    431
    432		if (can_tdc_is_enabled(&priv->can)) {
    433			tx_conf_msg.tdc_enabled = 1;
    434			tx_conf_msg.tdco = cpu_to_le16(priv->can.tdc.tdco);
    435			tx_conf_msg.tdcf = cpu_to_le16(priv->can.tdc.tdcf);
    436		}
    437
    438		conf_len = ES58X_FD_CANFD_CONF_LEN;
    439	} else {
    440		conf_len = ES58X_FD_CAN_CONF_LEN;
    441	}
    442
    443	return es58x_send_msg(es58x_dev, es58x_fd_cmd_type(netdev),
    444			      ES58X_FD_CAN_CMD_ID_ENABLE_CHANNEL,
    445			      &tx_conf_msg, conf_len, priv->channel_idx);
    446}
    447
    448static int es58x_fd_disable_channel(struct es58x_priv *priv)
    449{
    450	/* The type (ES58X_FD_CMD_TYPE_CAN or ES58X_FD_CMD_TYPE_CANFD) does
    451	 * not matter here.
    452	 */
    453	return es58x_send_msg(priv->es58x_dev, ES58X_FD_CMD_TYPE_CAN,
    454			      ES58X_FD_CAN_CMD_ID_DISABLE_CHANNEL,
    455			      ES58X_EMPTY_MSG, 0, priv->channel_idx);
    456}
    457
    458static int es58x_fd_get_timestamp(struct es58x_device *es58x_dev)
    459{
    460	return es58x_send_msg(es58x_dev, ES58X_FD_CMD_TYPE_DEVICE,
    461			      ES58X_FD_DEV_CMD_ID_TIMESTAMP, ES58X_EMPTY_MSG,
    462			      0, ES58X_CHANNEL_IDX_NA);
    463}
    464
    465/* Nominal bittiming constants for ES582.1 and ES584.1 as specified in
    466 * the microcontroller datasheet: "SAM E70/S70/V70/V71 Family" section
    467 * 49.6.8 "MCAN Nominal Bit Timing and Prescaler Register" from
    468 * Microchip.
    469 *
    470 * The values from the specification are the hardware register
    471 * values. To convert them to the functional values, all ranges were
    472 * incremented by 1 (e.g. range [0..n-1] changed to [1..n]).
    473 */
    474static const struct can_bittiming_const es58x_fd_nom_bittiming_const = {
    475	.name = "ES582.1/ES584.1",
    476	.tseg1_min = 2,
    477	.tseg1_max = 256,
    478	.tseg2_min = 2,
    479	.tseg2_max = 128,
    480	.sjw_max = 128,
    481	.brp_min = 1,
    482	.brp_max = 512,
    483	.brp_inc = 1
    484};
    485
    486/* Data bittiming constants for ES582.1 and ES584.1 as specified in
    487 * the microcontroller datasheet: "SAM E70/S70/V70/V71 Family" section
    488 * 49.6.4 "MCAN Data Bit Timing and Prescaler Register" from
    489 * Microchip.
    490 */
    491static const struct can_bittiming_const es58x_fd_data_bittiming_const = {
    492	.name = "ES582.1/ES584.1",
    493	.tseg1_min = 2,
    494	.tseg1_max = 32,
    495	.tseg2_min = 1,
    496	.tseg2_max = 16,
    497	.sjw_max = 8,
    498	.brp_min = 1,
    499	.brp_max = 32,
    500	.brp_inc = 1
    501};
    502
    503/* Transmission Delay Compensation constants for ES582.1 and ES584.1
    504 * as specified in the microcontroller datasheet: "SAM E70/S70/V70/V71
    505 * Family" section 49.6.15 "MCAN Transmitter Delay Compensation
    506 * Register" from Microchip.
    507 */
    508static const struct can_tdc_const es58x_tdc_const = {
    509	.tdcv_min = 0,
    510	.tdcv_max = 0, /* Manual mode not supported. */
    511	.tdco_min = 0,
    512	.tdco_max = 127,
    513	.tdcf_min = 0,
    514	.tdcf_max = 127
    515};
    516
    517const struct es58x_parameters es58x_fd_param = {
    518	.bittiming_const = &es58x_fd_nom_bittiming_const,
    519	.data_bittiming_const = &es58x_fd_data_bittiming_const,
    520	.tdc_const = &es58x_tdc_const,
    521	/* The devices use NXP TJA1044G transievers which guarantee
    522	 * the timing for data rates up to 5 Mbps. Bitrates up to 8
    523	 * Mbps work in an optimal environment but are not recommended
    524	 * for production environment.
    525	 */
    526	.bitrate_max = 8 * MEGA /* BPS */,
    527	.clock = {.freq = 80 * MEGA /* Hz */},
    528	.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY |
    529	    CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO |
    530	    CAN_CTRLMODE_CC_LEN8_DLC | CAN_CTRLMODE_TDC_AUTO,
    531	.tx_start_of_frame = 0xCEFA,	/* FACE in little endian */
    532	.rx_start_of_frame = 0xFECA,	/* CAFE in little endian */
    533	.tx_urb_cmd_max_len = ES58X_FD_TX_URB_CMD_MAX_LEN,
    534	.rx_urb_cmd_max_len = ES58X_FD_RX_URB_CMD_MAX_LEN,
    535	/* Size of internal device TX queue is 500.
    536	 *
    537	 * However, when reaching value around 278, the device's busy
    538	 * LED turns on and thus maximum value of 500 is never reached
    539	 * in practice. Also, when this value is too high, some error
    540	 * on the echo_msg were witnessed when the device is
    541	 * recovering from bus off.
    542	 *
    543	 * For above reasons, a value that would prevent the device
    544	 * from becoming busy was chosen. In practice, BQL would
    545	 * prevent the value from even getting closer to below
    546	 * maximum, so no impact on performance was measured.
    547	 */
    548	.fifo_mask = 255, /* echo_skb_max = 256 */
    549	.dql_min_limit = CAN_FRAME_LEN_MAX * 15, /* Empirical value. */
    550	.tx_bulk_max = ES58X_FD_TX_BULK_MAX,
    551	.urb_cmd_header_len = ES58X_FD_URB_CMD_HEADER_LEN,
    552	.rx_urb_max = ES58X_RX_URBS_MAX,
    553	.tx_urb_max = ES58X_TX_URBS_MAX
    554};
    555
    556const struct es58x_operators es58x_fd_ops = {
    557	.get_msg_len = es58x_fd_get_msg_len,
    558	.handle_urb_cmd = es58x_fd_handle_urb_cmd,
    559	.fill_urb_header = es58x_fd_fill_urb_header,
    560	.tx_can_msg = es58x_fd_tx_can_msg,
    561	.enable_channel = es58x_fd_enable_channel,
    562	.disable_channel = es58x_fd_disable_channel,
    563	.reset_device = NULL, /* Not implemented in the device firmware. */
    564	.get_timestamp = es58x_fd_get_timestamp
    565};