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1// SPDX-License-Identifier: GPL-2.0-or-later2/*******************************************************************************3 *4 * CTU CAN FD IP Core5 *6 * Copyright (C) 2015-2018 Ondrej Ille <ondrej.ille@gmail.com> FEE CTU7 * Copyright (C) 2018-2021 Ondrej Ille <ondrej.ille@gmail.com> self-funded8 * Copyright (C) 2018-2019 Martin Jerabek <martin.jerabek01@gmail.com> FEE CTU9 * Copyright (C) 2018-2022 Pavel Pisa <pisa@cmp.felk.cvut.cz> FEE CTU/self-funded10 *11 * Project advisors:12 *     Jiri Novak <jnovak@fel.cvut.cz>13 *     Pavel Pisa <pisa@cmp.felk.cvut.cz>14 *15 * Department of Measurement         (http://meas.fel.cvut.cz/)16 * Faculty of Electrical Engineering (http://www.fel.cvut.cz)17 * Czech Technical University        (http://www.cvut.cz/)18 ******************************************************************************/19 20#include <linux/clk.h>21#include <linux/errno.h>22#include <linux/ethtool.h>23#include <linux/init.h>24#include <linux/bitfield.h>25#include <linux/interrupt.h>26#include <linux/io.h>27#include <linux/kernel.h>28#include <linux/module.h>29#include <linux/skbuff.h>30#include <linux/string.h>31#include <linux/types.h>32#include <linux/can/error.h>33#include <linux/pm_runtime.h>34 35#include "ctucanfd.h"36#include "ctucanfd_kregs.h"37#include "ctucanfd_kframe.h"38 39#ifdef DEBUG40#define  ctucan_netdev_dbg(ndev, args...) \41		netdev_dbg(ndev, args)42#else43#define ctucan_netdev_dbg(...) do { } while (0)44#endif45 46#define CTUCANFD_ID 0xCAFD47 48/* TX buffer rotation:49 * - when a buffer transitions to empty state, rotate order and priorities50 * - if more buffers seem to transition at the same time, rotate by the number of buffers51 * - it may be assumed that buffers transition to empty state in FIFO order (because we manage52 *   priorities that way)53 * - at frame filling, do not rotate anything, just increment buffer modulo counter54 */55 56#define CTUCANFD_FLAG_RX_FFW_BUFFERED	157 58#define CTUCAN_STATE_TO_TEXT_ENTRY(st) \59		[st] = #st60 61enum ctucan_txtb_status {62	TXT_NOT_EXIST       = 0x0,63	TXT_RDY             = 0x1,64	TXT_TRAN            = 0x2,65	TXT_ABTP            = 0x3,66	TXT_TOK             = 0x4,67	TXT_ERR             = 0x6,68	TXT_ABT             = 0x7,69	TXT_ETY             = 0x8,70};71 72enum ctucan_txtb_command {73	TXT_CMD_SET_EMPTY   = 0x01,74	TXT_CMD_SET_READY   = 0x02,75	TXT_CMD_SET_ABORT   = 0x0476};77 78static const struct can_bittiming_const ctu_can_fd_bit_timing_max = {79	.name = "ctu_can_fd",80	.tseg1_min = 2,81	.tseg1_max = 190,82	.tseg2_min = 1,83	.tseg2_max = 63,84	.sjw_max = 31,85	.brp_min = 1,86	.brp_max = 8,87	.brp_inc = 1,88};89 90static const struct can_bittiming_const ctu_can_fd_bit_timing_data_max = {91	.name = "ctu_can_fd",92	.tseg1_min = 2,93	.tseg1_max = 94,94	.tseg2_min = 1,95	.tseg2_max = 31,96	.sjw_max = 31,97	.brp_min = 1,98	.brp_max = 2,99	.brp_inc = 1,100};101 102static const char * const ctucan_state_strings[CAN_STATE_MAX] = {103	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_ACTIVE),104	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_WARNING),105	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_ERROR_PASSIVE),106	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_BUS_OFF),107	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_STOPPED),108	CTUCAN_STATE_TO_TEXT_ENTRY(CAN_STATE_SLEEPING)109};110 111static void ctucan_write32_le(struct ctucan_priv *priv,112			      enum ctu_can_fd_can_registers reg, u32 val)113{114	iowrite32(val, priv->mem_base + reg);115}116 117static void ctucan_write32_be(struct ctucan_priv *priv,118			      enum ctu_can_fd_can_registers reg, u32 val)119{120	iowrite32be(val, priv->mem_base + reg);121}122 123static u32 ctucan_read32_le(struct ctucan_priv *priv,124			    enum ctu_can_fd_can_registers reg)125{126	return ioread32(priv->mem_base + reg);127}128 129static u32 ctucan_read32_be(struct ctucan_priv *priv,130			    enum ctu_can_fd_can_registers reg)131{132	return ioread32be(priv->mem_base + reg);133}134 135static void ctucan_write32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg, u32 val)136{137	priv->write_reg(priv, reg, val);138}139 140static u32 ctucan_read32(struct ctucan_priv *priv, enum ctu_can_fd_can_registers reg)141{142	return priv->read_reg(priv, reg);143}144 145static void ctucan_write_txt_buf(struct ctucan_priv *priv, enum ctu_can_fd_can_registers buf_base,146				 u32 offset, u32 val)147{148	priv->write_reg(priv, buf_base + offset, val);149}150 151#define CTU_CAN_FD_TXTNF(priv) (!!FIELD_GET(REG_STATUS_TXNF, ctucan_read32(priv, CTUCANFD_STATUS)))152#define CTU_CAN_FD_ENABLED(priv) (!!FIELD_GET(REG_MODE_ENA, ctucan_read32(priv, CTUCANFD_MODE)))153 154/**155 * ctucan_state_to_str() - Converts CAN controller state code to corresponding text156 * @state:	CAN controller state code157 *158 * Return: Pointer to string representation of the error state159 */160static const char *ctucan_state_to_str(enum can_state state)161{162	const char *txt = NULL;163 164	if (state >= 0 && state < CAN_STATE_MAX)165		txt = ctucan_state_strings[state];166	return txt ? txt : "UNKNOWN";167}168 169/**170 * ctucan_reset() - Issues software reset request to CTU CAN FD171 * @ndev:	Pointer to net_device structure172 *173 * Return: 0 for success, -%ETIMEDOUT if CAN controller does not leave reset174 */175static int ctucan_reset(struct net_device *ndev)176{177	struct ctucan_priv *priv = netdev_priv(ndev);178	int i = 100;179 180	ctucan_write32(priv, CTUCANFD_MODE, REG_MODE_RST);181	clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);182 183	do {184		u16 device_id = FIELD_GET(REG_DEVICE_ID_DEVICE_ID,185					  ctucan_read32(priv, CTUCANFD_DEVICE_ID));186 187		if (device_id == 0xCAFD)188			return 0;189		if (!i--) {190			netdev_warn(ndev, "device did not leave reset\n");191			return -ETIMEDOUT;192		}193		usleep_range(100, 200);194	} while (1);195}196 197/**198 * ctucan_set_btr() - Sets CAN bus bit timing in CTU CAN FD199 * @ndev:	Pointer to net_device structure200 * @bt:		Pointer to Bit timing structure201 * @nominal:	True - Nominal bit timing, False - Data bit timing202 *203 * Return: 0 - OK, -%EPERM if controller is enabled204 */205static int ctucan_set_btr(struct net_device *ndev, struct can_bittiming *bt, bool nominal)206{207	struct ctucan_priv *priv = netdev_priv(ndev);208	int max_ph1_len = 31;209	u32 btr = 0;210	u32 prop_seg = bt->prop_seg;211	u32 phase_seg1 = bt->phase_seg1;212 213	if (CTU_CAN_FD_ENABLED(priv)) {214		netdev_err(ndev, "BUG! Cannot set bittiming - CAN is enabled\n");215		return -EPERM;216	}217 218	if (nominal)219		max_ph1_len = 63;220 221	/* The timing calculation functions have only constraints on tseg1, which is prop_seg +222	 * phase1_seg combined. tseg1 is then split in half and stored into prog_seg and phase_seg1.223	 * In CTU CAN FD, PROP is 6/7 bits wide but PH1 only 6/5, so we must re-distribute the224	 * values here.225	 */226	if (phase_seg1 > max_ph1_len) {227		prop_seg += phase_seg1 - max_ph1_len;228		phase_seg1 = max_ph1_len;229		bt->prop_seg = prop_seg;230		bt->phase_seg1 = phase_seg1;231	}232 233	if (nominal) {234		btr = FIELD_PREP(REG_BTR_PROP, prop_seg);235		btr |= FIELD_PREP(REG_BTR_PH1, phase_seg1);236		btr |= FIELD_PREP(REG_BTR_PH2, bt->phase_seg2);237		btr |= FIELD_PREP(REG_BTR_BRP, bt->brp);238		btr |= FIELD_PREP(REG_BTR_SJW, bt->sjw);239 240		ctucan_write32(priv, CTUCANFD_BTR, btr);241	} else {242		btr = FIELD_PREP(REG_BTR_FD_PROP_FD, prop_seg);243		btr |= FIELD_PREP(REG_BTR_FD_PH1_FD, phase_seg1);244		btr |= FIELD_PREP(REG_BTR_FD_PH2_FD, bt->phase_seg2);245		btr |= FIELD_PREP(REG_BTR_FD_BRP_FD, bt->brp);246		btr |= FIELD_PREP(REG_BTR_FD_SJW_FD, bt->sjw);247 248		ctucan_write32(priv, CTUCANFD_BTR_FD, btr);249	}250 251	return 0;252}253 254/**255 * ctucan_set_bittiming() - CAN set nominal bit timing routine256 * @ndev:	Pointer to net_device structure257 *258 * Return: 0 on success, -%EPERM on error259 */260static int ctucan_set_bittiming(struct net_device *ndev)261{262	struct ctucan_priv *priv = netdev_priv(ndev);263	struct can_bittiming *bt = &priv->can.bittiming;264 265	/* Note that bt may be modified here */266	return ctucan_set_btr(ndev, bt, true);267}268 269/**270 * ctucan_set_data_bittiming() - CAN set data bit timing routine271 * @ndev:	Pointer to net_device structure272 *273 * Return: 0 on success, -%EPERM on error274 */275static int ctucan_set_data_bittiming(struct net_device *ndev)276{277	struct ctucan_priv *priv = netdev_priv(ndev);278	struct can_bittiming *dbt = &priv->can.data_bittiming;279 280	/* Note that dbt may be modified here */281	return ctucan_set_btr(ndev, dbt, false);282}283 284/**285 * ctucan_set_secondary_sample_point() - Sets secondary sample point in CTU CAN FD286 * @ndev:	Pointer to net_device structure287 *288 * Return: 0 on success, -%EPERM if controller is enabled289 */290static int ctucan_set_secondary_sample_point(struct net_device *ndev)291{292	struct ctucan_priv *priv = netdev_priv(ndev);293	struct can_bittiming *dbt = &priv->can.data_bittiming;294	int ssp_offset = 0;295	u32 ssp_cfg = 0; /* No SSP by default */296 297	if (CTU_CAN_FD_ENABLED(priv)) {298		netdev_err(ndev, "BUG! Cannot set SSP - CAN is enabled\n");299		return -EPERM;300	}301 302	/* Use SSP for bit-rates above 1 Mbits/s */303	if (dbt->bitrate > 1000000) {304		/* Calculate SSP in minimal time quanta */305		ssp_offset = (priv->can.clock.freq / 1000) * dbt->sample_point / dbt->bitrate;306 307		if (ssp_offset > 127) {308			netdev_warn(ndev, "SSP offset saturated to 127\n");309			ssp_offset = 127;310		}311 312		ssp_cfg = FIELD_PREP(REG_TRV_DELAY_SSP_OFFSET, ssp_offset);313		ssp_cfg |= FIELD_PREP(REG_TRV_DELAY_SSP_SRC, 0x1);314	}315 316	ctucan_write32(priv, CTUCANFD_TRV_DELAY, ssp_cfg);317 318	return 0;319}320 321/**322 * ctucan_set_mode() - Sets CTU CAN FDs mode323 * @priv:	Pointer to private data324 * @mode:	Pointer to controller modes to be set325 */326static void ctucan_set_mode(struct ctucan_priv *priv, const struct can_ctrlmode *mode)327{328	u32 mode_reg = ctucan_read32(priv, CTUCANFD_MODE);329 330	mode_reg = (mode->flags & CAN_CTRLMODE_LOOPBACK) ?331			(mode_reg | REG_MODE_ILBP) :332			(mode_reg & ~REG_MODE_ILBP);333 334	mode_reg = (mode->flags & CAN_CTRLMODE_LISTENONLY) ?335			(mode_reg | REG_MODE_BMM) :336			(mode_reg & ~REG_MODE_BMM);337 338	mode_reg = (mode->flags & CAN_CTRLMODE_FD) ?339			(mode_reg | REG_MODE_FDE) :340			(mode_reg & ~REG_MODE_FDE);341 342	mode_reg = (mode->flags & CAN_CTRLMODE_PRESUME_ACK) ?343			(mode_reg | REG_MODE_ACF) :344			(mode_reg & ~REG_MODE_ACF);345 346	mode_reg = (mode->flags & CAN_CTRLMODE_FD_NON_ISO) ?347			(mode_reg | REG_MODE_NISOFD) :348			(mode_reg & ~REG_MODE_NISOFD);349 350	/* One shot mode supported indirectly via Retransmit limit */351	mode_reg &= ~FIELD_PREP(REG_MODE_RTRTH, 0xF);352	mode_reg = (mode->flags & CAN_CTRLMODE_ONE_SHOT) ?353			(mode_reg | REG_MODE_RTRLE) :354			(mode_reg & ~REG_MODE_RTRLE);355 356	/* Some bits fixed:357	 *   TSTM  - Off, User shall not be able to change REC/TEC by hand during operation358	 */359	mode_reg &= ~REG_MODE_TSTM;360 361	ctucan_write32(priv, CTUCANFD_MODE, mode_reg);362}363 364/**365 * ctucan_chip_start() - This routine starts the driver366 * @ndev:	Pointer to net_device structure367 *368 * Routine expects that chip is in reset state. It setups initial369 * Tx buffers for FIFO priorities, sets bittiming, enables interrupts,370 * switches core to operational mode and changes controller371 * state to %CAN_STATE_STOPPED.372 *373 * Return: 0 on success and failure value on error374 */375static int ctucan_chip_start(struct net_device *ndev)376{377	struct ctucan_priv *priv = netdev_priv(ndev);378	u32 int_ena, int_msk;379	u32 mode_reg;380	int err;381	struct can_ctrlmode mode;382 383	priv->txb_prio = 0x01234567;384	priv->txb_head = 0;385	priv->txb_tail = 0;386	ctucan_write32(priv, CTUCANFD_TX_PRIORITY, priv->txb_prio);387 388	/* Configure bit-rates and ssp */389	err = ctucan_set_bittiming(ndev);390	if (err < 0)391		return err;392 393	err = ctucan_set_data_bittiming(ndev);394	if (err < 0)395		return err;396 397	err = ctucan_set_secondary_sample_point(ndev);398	if (err < 0)399		return err;400 401	/* Configure modes */402	mode.flags = priv->can.ctrlmode;403	mode.mask = 0xFFFFFFFF;404	ctucan_set_mode(priv, &mode);405 406	/* Configure interrupts */407	int_ena = REG_INT_STAT_RBNEI |408		  REG_INT_STAT_TXBHCI |409		  REG_INT_STAT_EWLI |410		  REG_INT_STAT_FCSI;411 412	/* Bus error reporting -> Allow Error/Arb.lost interrupts */413	if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) {414		int_ena |= REG_INT_STAT_ALI |415			   REG_INT_STAT_BEI;416	}417 418	int_msk = ~int_ena; /* Mask all disabled interrupts */419 420	/* It's after reset, so there is no need to clear anything */421	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, int_msk);422	ctucan_write32(priv, CTUCANFD_INT_ENA_SET, int_ena);423 424	/* Controller enters ERROR_ACTIVE on initial FCSI */425	priv->can.state = CAN_STATE_STOPPED;426 427	/* Enable the controller */428	mode_reg = ctucan_read32(priv, CTUCANFD_MODE);429	mode_reg |= REG_MODE_ENA;430	ctucan_write32(priv, CTUCANFD_MODE, mode_reg);431 432	return 0;433}434 435/**436 * ctucan_do_set_mode() - Sets mode of the driver437 * @ndev:	Pointer to net_device structure438 * @mode:	Tells the mode of the driver439 *440 * This check the drivers state and calls the corresponding modes to set.441 *442 * Return: 0 on success and failure value on error443 */444static int ctucan_do_set_mode(struct net_device *ndev, enum can_mode mode)445{446	int ret;447 448	switch (mode) {449	case CAN_MODE_START:450		ret = ctucan_reset(ndev);451		if (ret < 0)452			return ret;453		ret = ctucan_chip_start(ndev);454		if (ret < 0) {455			netdev_err(ndev, "ctucan_chip_start failed!\n");456			return ret;457		}458		netif_wake_queue(ndev);459		break;460	default:461		ret = -EOPNOTSUPP;462		break;463	}464 465	return ret;466}467 468/**469 * ctucan_get_tx_status() - Gets status of TXT buffer470 * @priv:	Pointer to private data471 * @buf:	Buffer index (0-based)472 *473 * Return: Status of TXT buffer474 */475static enum ctucan_txtb_status ctucan_get_tx_status(struct ctucan_priv *priv, u8 buf)476{477	u32 tx_status = ctucan_read32(priv, CTUCANFD_TX_STATUS);478	enum ctucan_txtb_status status = (tx_status >> (buf * 4)) & 0x7;479 480	return status;481}482 483/**484 * ctucan_is_txt_buf_writable() - Checks if frame can be inserted to TXT Buffer485 * @priv:	Pointer to private data486 * @buf:	Buffer index (0-based)487 *488 * Return: True - Frame can be inserted to TXT Buffer, False - If attempted, frame will not be489 *	   inserted to TXT Buffer490 */491static bool ctucan_is_txt_buf_writable(struct ctucan_priv *priv, u8 buf)492{493	enum ctucan_txtb_status buf_status;494 495	buf_status = ctucan_get_tx_status(priv, buf);496	if (buf_status == TXT_RDY || buf_status == TXT_TRAN || buf_status == TXT_ABTP)497		return false;498 499	return true;500}501 502/**503 * ctucan_insert_frame() - Inserts frame to TXT buffer504 * @priv:	Pointer to private data505 * @cf:		Pointer to CAN frame to be inserted506 * @buf:	TXT Buffer index to which frame is inserted (0-based)507 * @isfdf:	True - CAN FD Frame, False - CAN 2.0 Frame508 *509 * Return: True - Frame inserted successfully510 *	   False - Frame was not inserted due to one of:511 *			1. TXT Buffer is not writable (it is in wrong state)512 *			2. Invalid TXT buffer index513 *			3. Invalid frame length514 */515static bool ctucan_insert_frame(struct ctucan_priv *priv, const struct canfd_frame *cf, u8 buf,516				bool isfdf)517{518	u32 buf_base;519	u32 ffw = 0;520	u32 idw = 0;521	unsigned int i;522 523	if (buf >= priv->ntxbufs)524		return false;525 526	if (!ctucan_is_txt_buf_writable(priv, buf))527		return false;528 529	if (cf->len > CANFD_MAX_DLEN)530		return false;531 532	/* Prepare Frame format */533	if (cf->can_id & CAN_RTR_FLAG)534		ffw |= REG_FRAME_FORMAT_W_RTR;535 536	if (cf->can_id & CAN_EFF_FLAG)537		ffw |= REG_FRAME_FORMAT_W_IDE;538 539	if (isfdf) {540		ffw |= REG_FRAME_FORMAT_W_FDF;541		if (cf->flags & CANFD_BRS)542			ffw |= REG_FRAME_FORMAT_W_BRS;543	}544 545	ffw |= FIELD_PREP(REG_FRAME_FORMAT_W_DLC, can_fd_len2dlc(cf->len));546 547	/* Prepare identifier */548	if (cf->can_id & CAN_EFF_FLAG)549		idw = cf->can_id & CAN_EFF_MASK;550	else551		idw = FIELD_PREP(REG_IDENTIFIER_W_IDENTIFIER_BASE, cf->can_id & CAN_SFF_MASK);552 553	/* Write ID, Frame format, Don't write timestamp -> Time triggered transmission disabled */554	buf_base = (buf + 1) * 0x100;555	ctucan_write_txt_buf(priv, buf_base, CTUCANFD_FRAME_FORMAT_W, ffw);556	ctucan_write_txt_buf(priv, buf_base, CTUCANFD_IDENTIFIER_W, idw);557 558	/* Write Data payload */559	if (!(cf->can_id & CAN_RTR_FLAG)) {560		for (i = 0; i < cf->len; i += 4) {561			u32 data = le32_to_cpu(*(__le32 *)(cf->data + i));562 563			ctucan_write_txt_buf(priv, buf_base, CTUCANFD_DATA_1_4_W + i, data);564		}565	}566 567	return true;568}569 570/**571 * ctucan_give_txtb_cmd() - Applies command on TXT buffer572 * @priv:	Pointer to private data573 * @cmd:	Command to give574 * @buf:	Buffer index (0-based)575 */576static void ctucan_give_txtb_cmd(struct ctucan_priv *priv, enum ctucan_txtb_command cmd, u8 buf)577{578	u32 tx_cmd = cmd;579 580	tx_cmd |= 1 << (buf + 8);581	ctucan_write32(priv, CTUCANFD_TX_COMMAND, tx_cmd);582}583 584/**585 * ctucan_start_xmit() - Starts the transmission586 * @skb:	sk_buff pointer that contains data to be Txed587 * @ndev:	Pointer to net_device structure588 *589 * Invoked from upper layers to initiate transmission. Uses the next available free TXT Buffer and590 * populates its fields to start the transmission.591 *592 * Return: %NETDEV_TX_OK on success, %NETDEV_TX_BUSY when no free TXT buffer is available,593 *         negative return values reserved for error cases594 */595static netdev_tx_t ctucan_start_xmit(struct sk_buff *skb, struct net_device *ndev)596{597	struct ctucan_priv *priv = netdev_priv(ndev);598	struct canfd_frame *cf = (struct canfd_frame *)skb->data;599	u32 txtb_id;600	bool ok;601	unsigned long flags;602 603	if (can_dev_dropped_skb(ndev, skb))604		return NETDEV_TX_OK;605 606	if (unlikely(!CTU_CAN_FD_TXTNF(priv))) {607		netif_stop_queue(ndev);608		netdev_err(ndev, "BUG!, no TXB free when queue awake!\n");609		return NETDEV_TX_BUSY;610	}611 612	txtb_id = priv->txb_head % priv->ntxbufs;613	ctucan_netdev_dbg(ndev, "%s: using TXB#%u\n", __func__, txtb_id);614	ok = ctucan_insert_frame(priv, cf, txtb_id, can_is_canfd_skb(skb));615 616	if (!ok) {617		netdev_err(ndev, "BUG! TXNF set but cannot insert frame into TXTB! HW Bug?");618		kfree_skb(skb);619		ndev->stats.tx_dropped++;620		return NETDEV_TX_OK;621	}622 623	can_put_echo_skb(skb, ndev, txtb_id, 0);624 625	spin_lock_irqsave(&priv->tx_lock, flags);626	ctucan_give_txtb_cmd(priv, TXT_CMD_SET_READY, txtb_id);627	priv->txb_head++;628 629	/* Check if all TX buffers are full */630	if (!CTU_CAN_FD_TXTNF(priv))631		netif_stop_queue(ndev);632 633	spin_unlock_irqrestore(&priv->tx_lock, flags);634 635	return NETDEV_TX_OK;636}637 638/**639 * ctucan_read_rx_frame() - Reads frame from RX FIFO640 * @priv:	Pointer to CTU CAN FD's private data641 * @cf:		Pointer to CAN frame struct642 * @ffw:	Previously read frame format word643 *644 * Note: Frame format word must be read separately and provided in 'ffw'.645 */646static void ctucan_read_rx_frame(struct ctucan_priv *priv, struct canfd_frame *cf, u32 ffw)647{648	u32 idw;649	unsigned int i;650	unsigned int wc;651	unsigned int len;652 653	idw = ctucan_read32(priv, CTUCANFD_RX_DATA);654	if (FIELD_GET(REG_FRAME_FORMAT_W_IDE, ffw))655		cf->can_id = (idw & CAN_EFF_MASK) | CAN_EFF_FLAG;656	else657		cf->can_id = (idw >> 18) & CAN_SFF_MASK;658 659	/* BRS, ESI, RTR Flags */660	if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw)) {661		if (FIELD_GET(REG_FRAME_FORMAT_W_BRS, ffw))662			cf->flags |= CANFD_BRS;663		if (FIELD_GET(REG_FRAME_FORMAT_W_ESI_RSV, ffw))664			cf->flags |= CANFD_ESI;665	} else if (FIELD_GET(REG_FRAME_FORMAT_W_RTR, ffw)) {666		cf->can_id |= CAN_RTR_FLAG;667	}668 669	wc = FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw) - 3;670 671	/* DLC */672	if (FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw) <= 8) {673		len = FIELD_GET(REG_FRAME_FORMAT_W_DLC, ffw);674	} else {675		if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw))676			len = wc << 2;677		else678			len = 8;679	}680	cf->len = len;681	if (unlikely(len > wc * 4))682		len = wc * 4;683 684	/* Timestamp - Read and throw away */685	ctucan_read32(priv, CTUCANFD_RX_DATA);686	ctucan_read32(priv, CTUCANFD_RX_DATA);687 688	/* Data */689	for (i = 0; i < len; i += 4) {690		u32 data = ctucan_read32(priv, CTUCANFD_RX_DATA);691		*(__le32 *)(cf->data + i) = cpu_to_le32(data);692	}693	while (unlikely(i < wc * 4)) {694		ctucan_read32(priv, CTUCANFD_RX_DATA);695		i += 4;696	}697}698 699/**700 * ctucan_rx() -  Called from CAN ISR to complete the received frame processing701 * @ndev:	Pointer to net_device structure702 *703 * This function is invoked from the CAN isr(poll) to process the Rx frames. It does minimal704 * processing and invokes "netif_receive_skb" to complete further processing.705 * Return: 1 when frame is passed to the network layer, 0 when the first frame word is read but706 *	   system is out of free SKBs temporally and left code to resolve SKB allocation later,707 *         -%EAGAIN in a case of empty Rx FIFO.708 */709static int ctucan_rx(struct net_device *ndev)710{711	struct ctucan_priv *priv = netdev_priv(ndev);712	struct net_device_stats *stats = &ndev->stats;713	struct canfd_frame *cf;714	struct sk_buff *skb;715	u32 ffw;716 717	if (test_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags)) {718		ffw = priv->rxfrm_first_word;719		clear_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);720	} else {721		ffw = ctucan_read32(priv, CTUCANFD_RX_DATA);722	}723 724	if (!FIELD_GET(REG_FRAME_FORMAT_W_RWCNT, ffw))725		return -EAGAIN;726 727	if (FIELD_GET(REG_FRAME_FORMAT_W_FDF, ffw))728		skb = alloc_canfd_skb(ndev, &cf);729	else730		skb = alloc_can_skb(ndev, (struct can_frame **)&cf);731 732	if (unlikely(!skb)) {733		priv->rxfrm_first_word = ffw;734		set_bit(CTUCANFD_FLAG_RX_FFW_BUFFERED, &priv->drv_flags);735		return 0;736	}737 738	ctucan_read_rx_frame(priv, cf, ffw);739 740	stats->rx_bytes += cf->len;741	stats->rx_packets++;742	netif_receive_skb(skb);743 744	return 1;745}746 747/**748 * ctucan_read_fault_state() - Reads CTU CAN FDs fault confinement state.749 * @priv:	Pointer to private data750 *751 * Returns: Fault confinement state of controller752 */753static enum can_state ctucan_read_fault_state(struct ctucan_priv *priv)754{755	u32 fs;756	u32 rec_tec;757	u32 ewl;758 759	fs = ctucan_read32(priv, CTUCANFD_EWL);760	rec_tec = ctucan_read32(priv, CTUCANFD_REC);761	ewl = FIELD_GET(REG_EWL_EW_LIMIT, fs);762 763	if (FIELD_GET(REG_EWL_ERA, fs)) {764		if (ewl > FIELD_GET(REG_REC_REC_VAL, rec_tec) &&765		    ewl > FIELD_GET(REG_REC_TEC_VAL, rec_tec))766			return CAN_STATE_ERROR_ACTIVE;767		else768			return CAN_STATE_ERROR_WARNING;769	} else if (FIELD_GET(REG_EWL_ERP, fs)) {770		return CAN_STATE_ERROR_PASSIVE;771	} else if (FIELD_GET(REG_EWL_BOF, fs)) {772		return CAN_STATE_BUS_OFF;773	}774 775	WARN(true, "Invalid error state");776	return CAN_STATE_ERROR_PASSIVE;777}778 779/**780 * ctucan_get_rec_tec() - Reads REC/TEC counter values from controller781 * @priv:	Pointer to private data782 * @bec:	Pointer to Error counter structure783 */784static void ctucan_get_rec_tec(struct ctucan_priv *priv, struct can_berr_counter *bec)785{786	u32 err_ctrs = ctucan_read32(priv, CTUCANFD_REC);787 788	bec->rxerr = FIELD_GET(REG_REC_REC_VAL, err_ctrs);789	bec->txerr = FIELD_GET(REG_REC_TEC_VAL, err_ctrs);790}791 792/**793 * ctucan_err_interrupt() - Error frame ISR794 * @ndev:	net_device pointer795 * @isr:	interrupt status register value796 *797 * This is the CAN error interrupt and it will check the type of error and forward the error798 * frame to upper layers.799 */800static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)801{802	struct ctucan_priv *priv = netdev_priv(ndev);803	struct net_device_stats *stats = &ndev->stats;804	struct can_frame *cf;805	struct sk_buff *skb;806	enum can_state state;807	struct can_berr_counter bec;808	u32 err_capt_alc;809	int dologerr = net_ratelimit();810 811	ctucan_get_rec_tec(priv, &bec);812	state = ctucan_read_fault_state(priv);813	err_capt_alc = ctucan_read32(priv, CTUCANFD_ERR_CAPT);814 815	if (dologerr)816		netdev_info(ndev, "%s: ISR = 0x%08x, rxerr %d, txerr %d, error type %lu, pos %lu, ALC id_field %lu, bit %lu\n",817			    __func__, isr, bec.rxerr, bec.txerr,818			    FIELD_GET(REG_ERR_CAPT_ERR_TYPE, err_capt_alc),819			    FIELD_GET(REG_ERR_CAPT_ERR_POS, err_capt_alc),820			    FIELD_GET(REG_ERR_CAPT_ALC_ID_FIELD, err_capt_alc),821			    FIELD_GET(REG_ERR_CAPT_ALC_BIT, err_capt_alc));822 823	skb = alloc_can_err_skb(ndev, &cf);824 825	/* EWLI: error warning limit condition met826	 * FCSI: fault confinement state changed827	 * ALI:  arbitration lost (just informative)828	 * BEI:  bus error interrupt829	 */830	if (FIELD_GET(REG_INT_STAT_FCSI, isr) || FIELD_GET(REG_INT_STAT_EWLI, isr)) {831		netdev_info(ndev, "state changes from %s to %s\n",832			    ctucan_state_to_str(priv->can.state),833			    ctucan_state_to_str(state));834 835		if (priv->can.state == state)836			netdev_warn(ndev,837				    "current and previous state is the same! (missed interrupt?)\n");838 839		priv->can.state = state;840		switch (state) {841		case CAN_STATE_BUS_OFF:842			priv->can.can_stats.bus_off++;843			can_bus_off(ndev);844			if (skb)845				cf->can_id |= CAN_ERR_BUSOFF;846			break;847		case CAN_STATE_ERROR_PASSIVE:848			priv->can.can_stats.error_passive++;849			if (skb) {850				cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;851				cf->data[1] = (bec.rxerr > 127) ?852						CAN_ERR_CRTL_RX_PASSIVE :853						CAN_ERR_CRTL_TX_PASSIVE;854				cf->data[6] = bec.txerr;855				cf->data[7] = bec.rxerr;856			}857			break;858		case CAN_STATE_ERROR_WARNING:859			priv->can.can_stats.error_warning++;860			if (skb) {861				cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;862				cf->data[1] |= (bec.txerr > bec.rxerr) ?863					CAN_ERR_CRTL_TX_WARNING :864					CAN_ERR_CRTL_RX_WARNING;865				cf->data[6] = bec.txerr;866				cf->data[7] = bec.rxerr;867			}868			break;869		case CAN_STATE_ERROR_ACTIVE:870			cf->can_id |= CAN_ERR_CNT;871			cf->data[1] = CAN_ERR_CRTL_ACTIVE;872			cf->data[6] = bec.txerr;873			cf->data[7] = bec.rxerr;874			break;875		default:876			netdev_warn(ndev, "unhandled error state (%d:%s)!\n",877				    state, ctucan_state_to_str(state));878			break;879		}880	}881 882	/* Check for Arbitration Lost interrupt */883	if (FIELD_GET(REG_INT_STAT_ALI, isr)) {884		if (dologerr)885			netdev_info(ndev, "arbitration lost\n");886		priv->can.can_stats.arbitration_lost++;887		if (skb) {888			cf->can_id |= CAN_ERR_LOSTARB;889			cf->data[0] = CAN_ERR_LOSTARB_UNSPEC;890		}891	}892 893	/* Check for Bus Error interrupt */894	if (FIELD_GET(REG_INT_STAT_BEI, isr)) {895		netdev_info(ndev, "bus error\n");896		priv->can.can_stats.bus_error++;897		stats->rx_errors++;898		if (skb) {899			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;900			cf->data[2] = CAN_ERR_PROT_UNSPEC;901			cf->data[3] = CAN_ERR_PROT_LOC_UNSPEC;902		}903	}904 905	if (skb) {906		stats->rx_packets++;907		stats->rx_bytes += cf->can_dlc;908		netif_rx(skb);909	}910}911 912/**913 * ctucan_rx_poll() - Poll routine for rx packets (NAPI)914 * @napi:	NAPI structure pointer915 * @quota:	Max number of rx packets to be processed.916 *917 * This is the poll routine for rx part. It will process the packets maximux quota value.918 *919 * Return: Number of packets received920 */921static int ctucan_rx_poll(struct napi_struct *napi, int quota)922{923	struct net_device *ndev = napi->dev;924	struct ctucan_priv *priv = netdev_priv(ndev);925	int work_done = 0;926	u32 status;927	u32 framecnt;928	int res = 1;929 930	framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS));931	while (framecnt && work_done < quota && res > 0) {932		res = ctucan_rx(ndev);933		work_done++;934		framecnt = FIELD_GET(REG_RX_STATUS_RXFRC, ctucan_read32(priv, CTUCANFD_RX_STATUS));935	}936 937	/* Check for RX FIFO Overflow */938	status = ctucan_read32(priv, CTUCANFD_STATUS);939	if (FIELD_GET(REG_STATUS_DOR, status)) {940		struct net_device_stats *stats = &ndev->stats;941		struct can_frame *cf;942		struct sk_buff *skb;943 944		netdev_info(ndev, "rx_poll: rx fifo overflow\n");945		stats->rx_over_errors++;946		stats->rx_errors++;947		skb = alloc_can_err_skb(ndev, &cf);948		if (skb) {949			cf->can_id |= CAN_ERR_CRTL;950			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;951			stats->rx_packets++;952			stats->rx_bytes += cf->can_dlc;953			netif_rx(skb);954		}955 956		/* Clear Data Overrun */957		ctucan_write32(priv, CTUCANFD_COMMAND, REG_COMMAND_CDO);958	}959 960	if (!framecnt && res != 0) {961		if (napi_complete_done(napi, work_done)) {962			/* Clear and enable RBNEI. It is level-triggered, so963			 * there is no race condition.964			 */965			ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_RBNEI);966			ctucan_write32(priv, CTUCANFD_INT_MASK_CLR, REG_INT_STAT_RBNEI);967		}968	}969 970	return work_done;971}972 973/**974 * ctucan_rotate_txb_prio() - Rotates priorities of TXT Buffers975 * @ndev:	net_device pointer976 */977static void ctucan_rotate_txb_prio(struct net_device *ndev)978{979	struct ctucan_priv *priv = netdev_priv(ndev);980	u32 prio = priv->txb_prio;981 982	prio = (prio << 4) | ((prio >> ((priv->ntxbufs - 1) * 4)) & 0xF);983	ctucan_netdev_dbg(ndev, "%s: from 0x%08x to 0x%08x\n", __func__, priv->txb_prio, prio);984	priv->txb_prio = prio;985	ctucan_write32(priv, CTUCANFD_TX_PRIORITY, prio);986}987 988/**989 * ctucan_tx_interrupt() - Tx done Isr990 * @ndev:	net_device pointer991 */992static void ctucan_tx_interrupt(struct net_device *ndev)993{994	struct ctucan_priv *priv = netdev_priv(ndev);995	struct net_device_stats *stats = &ndev->stats;996	bool first = true;997	bool some_buffers_processed;998	unsigned long flags;999	enum ctucan_txtb_status txtb_status;1000	u32 txtb_id;1001 1002	/*  read tx_status1003	 *  if txb[n].finished (bit 2)1004	 *	if ok -> echo1005	 *	if error / aborted -> ?? (find how to handle oneshot mode)1006	 *	txb_tail++1007	 */1008	do {1009		spin_lock_irqsave(&priv->tx_lock, flags);1010 1011		some_buffers_processed = false;1012		while ((int)(priv->txb_head - priv->txb_tail) > 0) {1013			txtb_id = priv->txb_tail % priv->ntxbufs;1014			txtb_status = ctucan_get_tx_status(priv, txtb_id);1015 1016			ctucan_netdev_dbg(ndev, "TXI: TXB#%u: status 0x%x\n", txtb_id, txtb_status);1017 1018			switch (txtb_status) {1019			case TXT_TOK:1020				ctucan_netdev_dbg(ndev, "TXT_OK\n");1021				stats->tx_bytes += can_get_echo_skb(ndev, txtb_id, NULL);1022				stats->tx_packets++;1023				break;1024			case TXT_ERR:1025				/* This indicated that retransmit limit has been reached. Obviously1026				 * we should not echo the frame, but also not indicate any kind of1027				 * error. If desired, it was already reported (possible multiple1028				 * times) on each arbitration lost.1029				 */1030				netdev_warn(ndev, "TXB in Error state\n");1031				can_free_echo_skb(ndev, txtb_id, NULL);1032				stats->tx_dropped++;1033				break;1034			case TXT_ABT:1035				/* Same as for TXT_ERR, only with different cause. We *could*1036				 * re-queue the frame, but multiqueue/abort is not supported yet1037				 * anyway.1038				 */1039				netdev_warn(ndev, "TXB in Aborted state\n");1040				can_free_echo_skb(ndev, txtb_id, NULL);1041				stats->tx_dropped++;1042				break;1043			default:1044				/* Bug only if the first buffer is not finished, otherwise it is1045				 * pretty much expected.1046				 */1047				if (first) {1048					netdev_err(ndev,1049						   "BUG: TXB#%u not in a finished state (0x%x)!\n",1050						   txtb_id, txtb_status);1051					spin_unlock_irqrestore(&priv->tx_lock, flags);1052					/* do not clear nor wake */1053					return;1054				}1055				goto clear;1056			}1057			priv->txb_tail++;1058			first = false;1059			some_buffers_processed = true;1060			/* Adjust priorities *before* marking the buffer as empty. */1061			ctucan_rotate_txb_prio(ndev);1062			ctucan_give_txtb_cmd(priv, TXT_CMD_SET_EMPTY, txtb_id);1063		}1064clear:1065		spin_unlock_irqrestore(&priv->tx_lock, flags);1066 1067		/* If no buffers were processed this time, we cannot clear - that would introduce1068		 * a race condition.1069		 */1070		if (some_buffers_processed) {1071			/* Clear the interrupt again. We do not want to receive again interrupt for1072			 * the buffer already handled. If it is the last finished one then it would1073			 * cause log of spurious interrupt.1074			 */1075			ctucan_write32(priv, CTUCANFD_INT_STAT, REG_INT_STAT_TXBHCI);1076		}1077	} while (some_buffers_processed);1078 1079	spin_lock_irqsave(&priv->tx_lock, flags);1080 1081	/* Check if at least one TX buffer is free */1082	if (CTU_CAN_FD_TXTNF(priv))1083		netif_wake_queue(ndev);1084 1085	spin_unlock_irqrestore(&priv->tx_lock, flags);1086}1087 1088/**1089 * ctucan_interrupt() - CAN Isr1090 * @irq:	irq number1091 * @dev_id:	device id pointer1092 *1093 * This is the CTU CAN FD ISR. It checks for the type of interrupt1094 * and invokes the corresponding ISR.1095 *1096 * Return:1097 * IRQ_NONE - If CAN device is in sleep mode, IRQ_HANDLED otherwise1098 */1099static irqreturn_t ctucan_interrupt(int irq, void *dev_id)1100{1101	struct net_device *ndev = (struct net_device *)dev_id;1102	struct ctucan_priv *priv = netdev_priv(ndev);1103	u32 isr, icr;1104	u32 imask;1105	int irq_loops;1106 1107	for (irq_loops = 0; irq_loops < 10000; irq_loops++) {1108		/* Get the interrupt status */1109		isr = ctucan_read32(priv, CTUCANFD_INT_STAT);1110 1111		if (!isr)1112			return irq_loops ? IRQ_HANDLED : IRQ_NONE;1113 1114		/* Receive Buffer Not Empty Interrupt */1115		if (FIELD_GET(REG_INT_STAT_RBNEI, isr)) {1116			ctucan_netdev_dbg(ndev, "RXBNEI\n");1117			/* Mask RXBNEI the first, then clear interrupt and schedule NAPI. Even if1118			 * another IRQ fires, RBNEI will always be 0 (masked).1119			 */1120			icr = REG_INT_STAT_RBNEI;1121			ctucan_write32(priv, CTUCANFD_INT_MASK_SET, icr);1122			ctucan_write32(priv, CTUCANFD_INT_STAT, icr);1123			napi_schedule(&priv->napi);1124		}1125 1126		/* TXT Buffer HW Command Interrupt */1127		if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) {1128			ctucan_netdev_dbg(ndev, "TXBHCI\n");1129			/* Cleared inside */1130			ctucan_tx_interrupt(ndev);1131		}1132 1133		/* Error interrupts */1134		if (FIELD_GET(REG_INT_STAT_EWLI, isr) ||1135		    FIELD_GET(REG_INT_STAT_FCSI, isr) ||1136		    FIELD_GET(REG_INT_STAT_ALI, isr)) {1137			icr = isr & (REG_INT_STAT_EWLI | REG_INT_STAT_FCSI | REG_INT_STAT_ALI);1138 1139			ctucan_netdev_dbg(ndev, "some ERR interrupt: clearing 0x%08x\n", icr);1140			ctucan_write32(priv, CTUCANFD_INT_STAT, icr);1141			ctucan_err_interrupt(ndev, isr);1142		}1143		/* Ignore RI, TI, LFI, RFI, BSI */1144	}1145 1146	netdev_err(ndev, "%s: stuck interrupt (isr=0x%08x), stopping\n", __func__, isr);1147 1148	if (FIELD_GET(REG_INT_STAT_TXBHCI, isr)) {1149		int i;1150 1151		netdev_err(ndev, "txb_head=0x%08x txb_tail=0x%08x\n",1152			   priv->txb_head, priv->txb_tail);1153		for (i = 0; i < priv->ntxbufs; i++) {1154			u32 status = ctucan_get_tx_status(priv, i);1155 1156			netdev_err(ndev, "txb[%d] txb status=0x%08x\n", i, status);1157		}1158	}1159 1160	imask = 0xffffffff;1161	ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, imask);1162	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, imask);1163 1164	return IRQ_HANDLED;1165}1166 1167/**1168 * ctucan_chip_stop() - Driver stop routine1169 * @ndev:	Pointer to net_device structure1170 *1171 * This is the drivers stop routine. It will disable the1172 * interrupts and disable the controller.1173 */1174static void ctucan_chip_stop(struct net_device *ndev)1175{1176	struct ctucan_priv *priv = netdev_priv(ndev);1177	u32 mask = 0xffffffff;1178	u32 mode;1179 1180	/* Disable interrupts and disable CAN */1181	ctucan_write32(priv, CTUCANFD_INT_ENA_CLR, mask);1182	ctucan_write32(priv, CTUCANFD_INT_MASK_SET, mask);1183	mode = ctucan_read32(priv, CTUCANFD_MODE);1184	mode &= ~REG_MODE_ENA;1185	ctucan_write32(priv, CTUCANFD_MODE, mode);1186 1187	priv->can.state = CAN_STATE_STOPPED;1188}1189 1190/**1191 * ctucan_open() - Driver open routine1192 * @ndev:	Pointer to net_device structure1193 *1194 * This is the driver open routine.1195 * Return: 0 on success and failure value on error1196 */1197static int ctucan_open(struct net_device *ndev)1198{1199	struct ctucan_priv *priv = netdev_priv(ndev);1200	int ret;1201 1202	ret = pm_runtime_get_sync(priv->dev);1203	if (ret < 0) {1204		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",1205			   __func__, ret);1206		pm_runtime_put_noidle(priv->dev);1207		return ret;1208	}1209 1210	ret = ctucan_reset(ndev);1211	if (ret < 0)1212		goto err_reset;1213 1214	/* Common open */1215	ret = open_candev(ndev);1216	if (ret) {1217		netdev_warn(ndev, "open_candev failed!\n");1218		goto err_open;1219	}1220 1221	ret = request_irq(ndev->irq, ctucan_interrupt, priv->irq_flags, ndev->name, ndev);1222	if (ret < 0) {1223		netdev_err(ndev, "irq allocation for CAN failed\n");1224		goto err_irq;1225	}1226 1227	ret = ctucan_chip_start(ndev);1228	if (ret < 0) {1229		netdev_err(ndev, "ctucan_chip_start failed!\n");1230		goto err_chip_start;1231	}1232 1233	netdev_info(ndev, "ctu_can_fd device registered\n");1234	napi_enable(&priv->napi);1235	netif_start_queue(ndev);1236 1237	return 0;1238 1239err_chip_start:1240	free_irq(ndev->irq, ndev);1241err_irq:1242	close_candev(ndev);1243err_open:1244err_reset:1245	pm_runtime_put(priv->dev);1246 1247	return ret;1248}1249 1250/**1251 * ctucan_close() - Driver close routine1252 * @ndev:	Pointer to net_device structure1253 *1254 * Return: 0 always1255 */1256static int ctucan_close(struct net_device *ndev)1257{1258	struct ctucan_priv *priv = netdev_priv(ndev);1259 1260	netif_stop_queue(ndev);1261	napi_disable(&priv->napi);1262	ctucan_chip_stop(ndev);1263	free_irq(ndev->irq, ndev);1264	close_candev(ndev);1265 1266	pm_runtime_put(priv->dev);1267 1268	return 0;1269}1270 1271/**1272 * ctucan_get_berr_counter() - error counter routine1273 * @ndev:	Pointer to net_device structure1274 * @bec:	Pointer to can_berr_counter structure1275 *1276 * This is the driver error counter routine.1277 * Return: 0 on success and failure value on error1278 */1279static int ctucan_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec)1280{1281	struct ctucan_priv *priv = netdev_priv(ndev);1282	int ret;1283 1284	ret = pm_runtime_get_sync(priv->dev);1285	if (ret < 0) {1286		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n", __func__, ret);1287		pm_runtime_put_noidle(priv->dev);1288		return ret;1289	}1290 1291	ctucan_get_rec_tec(priv, bec);1292	pm_runtime_put(priv->dev);1293 1294	return 0;1295}1296 1297static const struct net_device_ops ctucan_netdev_ops = {1298	.ndo_open	= ctucan_open,1299	.ndo_stop	= ctucan_close,1300	.ndo_start_xmit	= ctucan_start_xmit,1301	.ndo_change_mtu	= can_change_mtu,1302};1303 1304static const struct ethtool_ops ctucan_ethtool_ops = {1305	.get_ts_info = ethtool_op_get_ts_info,1306};1307 1308int ctucan_suspend(struct device *dev)1309{1310	struct net_device *ndev = dev_get_drvdata(dev);1311	struct ctucan_priv *priv = netdev_priv(ndev);1312 1313	if (netif_running(ndev)) {1314		netif_stop_queue(ndev);1315		netif_device_detach(ndev);1316	}1317 1318	priv->can.state = CAN_STATE_SLEEPING;1319 1320	return 0;1321}1322EXPORT_SYMBOL(ctucan_suspend);1323 1324int ctucan_resume(struct device *dev)1325{1326	struct net_device *ndev = dev_get_drvdata(dev);1327	struct ctucan_priv *priv = netdev_priv(ndev);1328 1329	priv->can.state = CAN_STATE_ERROR_ACTIVE;1330 1331	if (netif_running(ndev)) {1332		netif_device_attach(ndev);1333		netif_start_queue(ndev);1334	}1335 1336	return 0;1337}1338EXPORT_SYMBOL(ctucan_resume);1339 1340int ctucan_probe_common(struct device *dev, void __iomem *addr, int irq, unsigned int ntxbufs,1341			unsigned long can_clk_rate, int pm_enable_call,1342			void (*set_drvdata_fnc)(struct device *dev, struct net_device *ndev))1343{1344	struct ctucan_priv *priv;1345	struct net_device *ndev;1346	int ret;1347 1348	/* Create a CAN device instance */1349	ndev = alloc_candev(sizeof(struct ctucan_priv), ntxbufs);1350	if (!ndev)1351		return -ENOMEM;1352 1353	priv = netdev_priv(ndev);1354	spin_lock_init(&priv->tx_lock);1355	INIT_LIST_HEAD(&priv->peers_on_pdev);1356	priv->ntxbufs = ntxbufs;1357	priv->dev = dev;1358	priv->can.bittiming_const = &ctu_can_fd_bit_timing_max;1359	priv->can.data_bittiming_const = &ctu_can_fd_bit_timing_data_max;1360	priv->can.do_set_mode = ctucan_do_set_mode;1361 1362	/* Needed for timing adjustment to be performed as soon as possible */1363	priv->can.do_set_bittiming = ctucan_set_bittiming;1364	priv->can.do_set_data_bittiming = ctucan_set_data_bittiming;1365 1366	priv->can.do_get_berr_counter = ctucan_get_berr_counter;1367	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK1368					| CAN_CTRLMODE_LISTENONLY1369					| CAN_CTRLMODE_FD1370					| CAN_CTRLMODE_PRESUME_ACK1371					| CAN_CTRLMODE_BERR_REPORTING1372					| CAN_CTRLMODE_FD_NON_ISO1373					| CAN_CTRLMODE_ONE_SHOT;1374	priv->mem_base = addr;1375 1376	/* Get IRQ for the device */1377	ndev->irq = irq;1378	ndev->flags |= IFF_ECHO;	/* We support local echo */1379 1380	if (set_drvdata_fnc)1381		set_drvdata_fnc(dev, ndev);1382	SET_NETDEV_DEV(ndev, dev);1383	ndev->netdev_ops = &ctucan_netdev_ops;1384	ndev->ethtool_ops = &ctucan_ethtool_ops;1385 1386	/* Getting the can_clk info */1387	if (!can_clk_rate) {1388		priv->can_clk = devm_clk_get(dev, NULL);1389		if (IS_ERR(priv->can_clk)) {1390			dev_err(dev, "Device clock not found.\n");1391			ret = PTR_ERR(priv->can_clk);1392			goto err_free;1393		}1394		can_clk_rate = clk_get_rate(priv->can_clk);1395	}1396 1397	priv->write_reg = ctucan_write32_le;1398	priv->read_reg = ctucan_read32_le;1399 1400	if (pm_enable_call)1401		pm_runtime_enable(dev);1402	ret = pm_runtime_get_sync(dev);1403	if (ret < 0) {1404		netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",1405			   __func__, ret);1406		pm_runtime_put_noidle(priv->dev);1407		goto err_pmdisable;1408	}1409 1410	/* Check for big-endianity and set according IO-accessors */1411	if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) {1412		priv->write_reg = ctucan_write32_be;1413		priv->read_reg = ctucan_read32_be;1414		if ((ctucan_read32(priv, CTUCANFD_DEVICE_ID) & 0xFFFF) != CTUCANFD_ID) {1415			netdev_err(ndev, "CTU_CAN_FD signature not found\n");1416			ret = -ENODEV;1417			goto err_deviceoff;1418		}1419	}1420 1421	ret = ctucan_reset(ndev);1422	if (ret < 0)1423		goto err_deviceoff;1424 1425	priv->can.clock.freq = can_clk_rate;1426 1427	netif_napi_add(ndev, &priv->napi, ctucan_rx_poll);1428 1429	ret = register_candev(ndev);1430	if (ret) {1431		dev_err(dev, "fail to register failed (err=%d)\n", ret);1432		goto err_deviceoff;1433	}1434 1435	pm_runtime_put(dev);1436 1437	netdev_dbg(ndev, "mem_base=0x%p irq=%d clock=%d, no. of txt buffers:%d\n",1438		   priv->mem_base, ndev->irq, priv->can.clock.freq, priv->ntxbufs);1439 1440	return 0;1441 1442err_deviceoff:1443	pm_runtime_put(priv->dev);1444err_pmdisable:1445	if (pm_enable_call)1446		pm_runtime_disable(dev);1447err_free:1448	list_del_init(&priv->peers_on_pdev);1449	free_candev(ndev);1450	return ret;1451}1452EXPORT_SYMBOL(ctucan_probe_common);1453 1454MODULE_LICENSE("GPL");1455MODULE_AUTHOR("Martin Jerabek <martin.jerabek01@gmail.com>");1456MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>");1457MODULE_AUTHOR("Ondrej Ille <ondrej.ille@gmail.com>");1458MODULE_DESCRIPTION("CTU CAN FD interface");1459