2 * flexcan.c - FLEXCAN CAN controller driver
4 * Copyright (c) 2005-2006 Varma Electronics Oy
5 * Copyright (c) 2009 Sascha Hauer, Pengutronix
6 * Copyright (c) 2010 Marc Kleine-Budde, Pengutronix
8 * Based on code originally by Andrey Volkov <avolkov@varma-el.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation version 2.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
22 #include <linux/netdevice.h>
23 #include <linux/can.h>
24 #include <linux/can/dev.h>
25 #include <linux/can/error.h>
26 #include <linux/can/led.h>
27 #include <linux/clk.h>
28 #include <linux/delay.h>
29 #include <linux/if_arp.h>
30 #include <linux/if_ether.h>
31 #include <linux/interrupt.h>
33 #include <linux/kernel.h>
34 #include <linux/list.h>
35 #include <linux/module.h>
37 #include <linux/of_device.h>
38 #include <linux/platform_device.h>
39 #include <linux/regulator/consumer.h>
41 #define DRV_NAME "flexcan"
43 /* 8 for RX fifo and 2 error handling */
44 #define FLEXCAN_NAPI_WEIGHT (8 + 2)
46 /* FLEXCAN module configuration register (CANMCR) bits */
47 #define FLEXCAN_MCR_MDIS BIT(31)
48 #define FLEXCAN_MCR_FRZ BIT(30)
49 #define FLEXCAN_MCR_FEN BIT(29)
50 #define FLEXCAN_MCR_HALT BIT(28)
51 #define FLEXCAN_MCR_NOT_RDY BIT(27)
52 #define FLEXCAN_MCR_WAK_MSK BIT(26)
53 #define FLEXCAN_MCR_SOFTRST BIT(25)
54 #define FLEXCAN_MCR_FRZ_ACK BIT(24)
55 #define FLEXCAN_MCR_SUPV BIT(23)
56 #define FLEXCAN_MCR_SLF_WAK BIT(22)
57 #define FLEXCAN_MCR_WRN_EN BIT(21)
58 #define FLEXCAN_MCR_LPM_ACK BIT(20)
59 #define FLEXCAN_MCR_WAK_SRC BIT(19)
60 #define FLEXCAN_MCR_DOZE BIT(18)
61 #define FLEXCAN_MCR_SRX_DIS BIT(17)
62 #define FLEXCAN_MCR_BCC BIT(16)
63 #define FLEXCAN_MCR_LPRIO_EN BIT(13)
64 #define FLEXCAN_MCR_AEN BIT(12)
65 #define FLEXCAN_MCR_MAXMB(x) ((x) & 0x1f)
66 #define FLEXCAN_MCR_IDAM_A (0 << 8)
67 #define FLEXCAN_MCR_IDAM_B (1 << 8)
68 #define FLEXCAN_MCR_IDAM_C (2 << 8)
69 #define FLEXCAN_MCR_IDAM_D (3 << 8)
71 /* FLEXCAN control register (CANCTRL) bits */
72 #define FLEXCAN_CTRL_PRESDIV(x) (((x) & 0xff) << 24)
73 #define FLEXCAN_CTRL_RJW(x) (((x) & 0x03) << 22)
74 #define FLEXCAN_CTRL_PSEG1(x) (((x) & 0x07) << 19)
75 #define FLEXCAN_CTRL_PSEG2(x) (((x) & 0x07) << 16)
76 #define FLEXCAN_CTRL_BOFF_MSK BIT(15)
77 #define FLEXCAN_CTRL_ERR_MSK BIT(14)
78 #define FLEXCAN_CTRL_CLK_SRC BIT(13)
79 #define FLEXCAN_CTRL_LPB BIT(12)
80 #define FLEXCAN_CTRL_TWRN_MSK BIT(11)
81 #define FLEXCAN_CTRL_RWRN_MSK BIT(10)
82 #define FLEXCAN_CTRL_SMP BIT(7)
83 #define FLEXCAN_CTRL_BOFF_REC BIT(6)
84 #define FLEXCAN_CTRL_TSYN BIT(5)
85 #define FLEXCAN_CTRL_LBUF BIT(4)
86 #define FLEXCAN_CTRL_LOM BIT(3)
87 #define FLEXCAN_CTRL_PROPSEG(x) ((x) & 0x07)
88 #define FLEXCAN_CTRL_ERR_BUS (FLEXCAN_CTRL_ERR_MSK)
89 #define FLEXCAN_CTRL_ERR_STATE \
90 (FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
91 FLEXCAN_CTRL_BOFF_MSK)
92 #define FLEXCAN_CTRL_ERR_ALL \
93 (FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)
95 /* FLEXCAN control register 2 (CTRL2) bits */
96 #define FLEXCAN_CRL2_ECRWRE BIT(29)
97 #define FLEXCAN_CRL2_WRMFRZ BIT(28)
98 #define FLEXCAN_CRL2_RFFN(x) (((x) & 0x0f) << 24)
99 #define FLEXCAN_CRL2_TASD(x) (((x) & 0x1f) << 19)
100 #define FLEXCAN_CRL2_MRP BIT(18)
101 #define FLEXCAN_CRL2_RRS BIT(17)
102 #define FLEXCAN_CRL2_EACEN BIT(16)
104 /* FLEXCAN memory error control register (MECR) bits */
105 #define FLEXCAN_MECR_ECRWRDIS BIT(31)
106 #define FLEXCAN_MECR_HANCEI_MSK BIT(19)
107 #define FLEXCAN_MECR_FANCEI_MSK BIT(18)
108 #define FLEXCAN_MECR_CEI_MSK BIT(16)
109 #define FLEXCAN_MECR_HAERRIE BIT(15)
110 #define FLEXCAN_MECR_FAERRIE BIT(14)
111 #define FLEXCAN_MECR_EXTERRIE BIT(13)
112 #define FLEXCAN_MECR_RERRDIS BIT(9)
113 #define FLEXCAN_MECR_ECCDIS BIT(8)
114 #define FLEXCAN_MECR_NCEFAFRZ BIT(7)
116 /* FLEXCAN error and status register (ESR) bits */
117 #define FLEXCAN_ESR_TWRN_INT BIT(17)
118 #define FLEXCAN_ESR_RWRN_INT BIT(16)
119 #define FLEXCAN_ESR_BIT1_ERR BIT(15)
120 #define FLEXCAN_ESR_BIT0_ERR BIT(14)
121 #define FLEXCAN_ESR_ACK_ERR BIT(13)
122 #define FLEXCAN_ESR_CRC_ERR BIT(12)
123 #define FLEXCAN_ESR_FRM_ERR BIT(11)
124 #define FLEXCAN_ESR_STF_ERR BIT(10)
125 #define FLEXCAN_ESR_TX_WRN BIT(9)
126 #define FLEXCAN_ESR_RX_WRN BIT(8)
127 #define FLEXCAN_ESR_IDLE BIT(7)
128 #define FLEXCAN_ESR_TXRX BIT(6)
129 #define FLEXCAN_EST_FLT_CONF_SHIFT (4)
130 #define FLEXCAN_ESR_FLT_CONF_MASK (0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
131 #define FLEXCAN_ESR_FLT_CONF_ACTIVE (0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
132 #define FLEXCAN_ESR_FLT_CONF_PASSIVE (0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
133 #define FLEXCAN_ESR_BOFF_INT BIT(2)
134 #define FLEXCAN_ESR_ERR_INT BIT(1)
135 #define FLEXCAN_ESR_WAK_INT BIT(0)
136 #define FLEXCAN_ESR_ERR_BUS \
137 (FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
138 FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
139 FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
140 #define FLEXCAN_ESR_ERR_STATE \
141 (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
142 #define FLEXCAN_ESR_ERR_ALL \
143 (FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
144 #define FLEXCAN_ESR_ALL_INT \
145 (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
146 FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
148 /* FLEXCAN interrupt flag register (IFLAG) bits */
149 #define FLEXCAN_TX_BUF_ID 8
150 #define FLEXCAN_IFLAG_BUF(x) BIT(x)
151 #define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW BIT(7)
152 #define FLEXCAN_IFLAG_RX_FIFO_WARN BIT(6)
153 #define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE BIT(5)
154 #define FLEXCAN_IFLAG_DEFAULT \
155 (FLEXCAN_IFLAG_RX_FIFO_OVERFLOW | FLEXCAN_IFLAG_RX_FIFO_AVAILABLE | \
156 FLEXCAN_IFLAG_BUF(FLEXCAN_TX_BUF_ID))
158 /* FLEXCAN message buffers */
159 #define FLEXCAN_MB_CNT_CODE(x) (((x) & 0xf) << 24)
160 #define FLEXCAN_MB_CNT_SRR BIT(22)
161 #define FLEXCAN_MB_CNT_IDE BIT(21)
162 #define FLEXCAN_MB_CNT_RTR BIT(20)
163 #define FLEXCAN_MB_CNT_LENGTH(x) (((x) & 0xf) << 16)
164 #define FLEXCAN_MB_CNT_TIMESTAMP(x) ((x) & 0xffff)
166 #define FLEXCAN_MB_CODE_MASK (0xf0ffffff)
168 #define FLEXCAN_TIMEOUT_US (50)
171 * FLEXCAN hardware feature flags
173 * Below is some version info we got:
174 * SOC Version IP-Version Glitch- [TR]WRN_INT Memory err
175 * Filter? connected? detection
176 * MX25 FlexCAN2 03.00.00.00 no no no
177 * MX28 FlexCAN2 03.00.04.00 yes yes no
178 * MX35 FlexCAN2 03.00.00.00 no no no
179 * MX53 FlexCAN2 03.00.00.00 yes no no
180 * MX6s FlexCAN3 10.00.12.00 yes yes no
181 * VF610 FlexCAN3 ? no yes yes
183 * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
185 #define FLEXCAN_HAS_V10_FEATURES BIT(1) /* For core version >= 10 */
186 #define FLEXCAN_HAS_BROKEN_ERR_STATE BIT(2) /* [TR]WRN_INT not connected */
187 #define FLEXCAN_HAS_MECR_FEATURES BIT(3) /* Memory error detection */
189 /* Structure of the message buffer */
196 /* Structure of the hardware registers */
197 struct flexcan_regs {
200 u32 timer; /* 0x08 */
201 u32 _reserved1; /* 0x0c */
202 u32 rxgmask; /* 0x10 */
203 u32 rx14mask; /* 0x14 */
204 u32 rx15mask; /* 0x18 */
207 u32 imask2; /* 0x24 */
208 u32 imask1; /* 0x28 */
209 u32 iflag2; /* 0x2c */
210 u32 iflag1; /* 0x30 */
213 u32 imeur; /* 0x3c */
216 u32 rxfgmask; /* 0x48 */
217 u32 rxfir; /* 0x4c */
218 u32 _reserved3[12]; /* 0x50 */
219 struct flexcan_mb cantxfg[64]; /* 0x80 */
221 u32 mecr; /* 0xae0 */
222 u32 erriar; /* 0xae4 */
223 u32 erridpr; /* 0xae8 */
224 u32 errippr; /* 0xaec */
225 u32 rerrar; /* 0xaf0 */
226 u32 rerrdr; /* 0xaf4 */
227 u32 rerrsynr; /* 0xaf8 */
228 u32 errsr; /* 0xafc */
231 struct flexcan_devtype_data {
232 u32 features; /* hardware controller features */
235 struct flexcan_priv {
237 struct net_device *dev;
238 struct napi_struct napi;
242 u32 reg_ctrl_default;
246 struct flexcan_platform_data *pdata;
247 const struct flexcan_devtype_data *devtype_data;
248 struct regulator *reg_xceiver;
251 static struct flexcan_devtype_data fsl_p1010_devtype_data = {
252 .features = FLEXCAN_HAS_BROKEN_ERR_STATE,
254 static struct flexcan_devtype_data fsl_imx28_devtype_data;
255 static struct flexcan_devtype_data fsl_imx6q_devtype_data = {
256 .features = FLEXCAN_HAS_V10_FEATURES,
258 static struct flexcan_devtype_data fsl_vf610_devtype_data = {
259 .features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_MECR_FEATURES,
262 static const struct can_bittiming_const flexcan_bittiming_const = {
275 * Abstract off the read/write for arm versus ppc. This
276 * assumes that PPC uses big-endian registers and everything
277 * else uses little-endian registers, independent of CPU
280 #if defined(CONFIG_PPC)
281 static inline u32 flexcan_read(void __iomem *addr)
283 return in_be32(addr);
286 static inline void flexcan_write(u32 val, void __iomem *addr)
291 static inline u32 flexcan_read(void __iomem *addr)
296 static inline void flexcan_write(u32 val, void __iomem *addr)
302 static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
304 if (!priv->reg_xceiver)
307 return regulator_enable(priv->reg_xceiver);
310 static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
312 if (!priv->reg_xceiver)
315 return regulator_disable(priv->reg_xceiver);
318 static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv,
321 return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
322 (reg_esr & FLEXCAN_ESR_ERR_BUS);
325 static int flexcan_chip_enable(struct flexcan_priv *priv)
327 struct flexcan_regs __iomem *regs = priv->base;
328 unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
331 reg = flexcan_read(®s->mcr);
332 reg &= ~FLEXCAN_MCR_MDIS;
333 flexcan_write(reg, ®s->mcr);
335 while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK))
336 usleep_range(10, 20);
338 if (flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)
344 static int flexcan_chip_disable(struct flexcan_priv *priv)
346 struct flexcan_regs __iomem *regs = priv->base;
347 unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
350 reg = flexcan_read(®s->mcr);
351 reg |= FLEXCAN_MCR_MDIS;
352 flexcan_write(reg, ®s->mcr);
354 while (timeout-- && !(flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK))
355 usleep_range(10, 20);
357 if (!(flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK))
363 static int flexcan_chip_freeze(struct flexcan_priv *priv)
365 struct flexcan_regs __iomem *regs = priv->base;
366 unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate;
369 reg = flexcan_read(®s->mcr);
370 reg |= FLEXCAN_MCR_HALT;
371 flexcan_write(reg, ®s->mcr);
373 while (timeout-- && !(flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK))
374 usleep_range(100, 200);
376 if (!(flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK))
382 static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
384 struct flexcan_regs __iomem *regs = priv->base;
385 unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
388 reg = flexcan_read(®s->mcr);
389 reg &= ~FLEXCAN_MCR_HALT;
390 flexcan_write(reg, ®s->mcr);
392 while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK))
393 usleep_range(10, 20);
395 if (flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)
401 static int flexcan_chip_softreset(struct flexcan_priv *priv)
403 struct flexcan_regs __iomem *regs = priv->base;
404 unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
406 flexcan_write(FLEXCAN_MCR_SOFTRST, ®s->mcr);
407 while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_SOFTRST))
408 usleep_range(10, 20);
410 if (flexcan_read(®s->mcr) & FLEXCAN_MCR_SOFTRST)
417 static int __flexcan_get_berr_counter(const struct net_device *dev,
418 struct can_berr_counter *bec)
420 const struct flexcan_priv *priv = netdev_priv(dev);
421 struct flexcan_regs __iomem *regs = priv->base;
422 u32 reg = flexcan_read(®s->ecr);
424 bec->txerr = (reg >> 0) & 0xff;
425 bec->rxerr = (reg >> 8) & 0xff;
430 static int flexcan_get_berr_counter(const struct net_device *dev,
431 struct can_berr_counter *bec)
433 const struct flexcan_priv *priv = netdev_priv(dev);
436 err = clk_prepare_enable(priv->clk_ipg);
440 err = clk_prepare_enable(priv->clk_per);
442 goto out_disable_ipg;
444 err = __flexcan_get_berr_counter(dev, bec);
446 clk_disable_unprepare(priv->clk_per);
448 clk_disable_unprepare(priv->clk_ipg);
453 static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
455 const struct flexcan_priv *priv = netdev_priv(dev);
456 struct flexcan_regs __iomem *regs = priv->base;
457 struct can_frame *cf = (struct can_frame *)skb->data;
459 u32 ctrl = FLEXCAN_MB_CNT_CODE(0xc) | (cf->can_dlc << 16);
461 if (can_dropped_invalid_skb(dev, skb))
464 netif_stop_queue(dev);
466 if (cf->can_id & CAN_EFF_FLAG) {
467 can_id = cf->can_id & CAN_EFF_MASK;
468 ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
470 can_id = (cf->can_id & CAN_SFF_MASK) << 18;
473 if (cf->can_id & CAN_RTR_FLAG)
474 ctrl |= FLEXCAN_MB_CNT_RTR;
476 if (cf->can_dlc > 0) {
477 u32 data = be32_to_cpup((__be32 *)&cf->data[0]);
478 flexcan_write(data, ®s->cantxfg[FLEXCAN_TX_BUF_ID].data[0]);
480 if (cf->can_dlc > 3) {
481 u32 data = be32_to_cpup((__be32 *)&cf->data[4]);
482 flexcan_write(data, ®s->cantxfg[FLEXCAN_TX_BUF_ID].data[1]);
485 can_put_echo_skb(skb, dev, 0);
487 flexcan_write(can_id, ®s->cantxfg[FLEXCAN_TX_BUF_ID].can_id);
488 flexcan_write(ctrl, ®s->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
493 static void do_bus_err(struct net_device *dev,
494 struct can_frame *cf, u32 reg_esr)
496 struct flexcan_priv *priv = netdev_priv(dev);
497 int rx_errors = 0, tx_errors = 0;
499 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
501 if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
502 netdev_dbg(dev, "BIT1_ERR irq\n");
503 cf->data[2] |= CAN_ERR_PROT_BIT1;
506 if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
507 netdev_dbg(dev, "BIT0_ERR irq\n");
508 cf->data[2] |= CAN_ERR_PROT_BIT0;
511 if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
512 netdev_dbg(dev, "ACK_ERR irq\n");
513 cf->can_id |= CAN_ERR_ACK;
514 cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
517 if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
518 netdev_dbg(dev, "CRC_ERR irq\n");
519 cf->data[2] |= CAN_ERR_PROT_BIT;
520 cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
523 if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
524 netdev_dbg(dev, "FRM_ERR irq\n");
525 cf->data[2] |= CAN_ERR_PROT_FORM;
528 if (reg_esr & FLEXCAN_ESR_STF_ERR) {
529 netdev_dbg(dev, "STF_ERR irq\n");
530 cf->data[2] |= CAN_ERR_PROT_STUFF;
534 priv->can.can_stats.bus_error++;
536 dev->stats.rx_errors++;
538 dev->stats.tx_errors++;
541 static int flexcan_poll_bus_err(struct net_device *dev, u32 reg_esr)
544 struct can_frame *cf;
546 skb = alloc_can_err_skb(dev, &cf);
550 do_bus_err(dev, cf, reg_esr);
551 netif_receive_skb(skb);
553 dev->stats.rx_packets++;
554 dev->stats.rx_bytes += cf->can_dlc;
559 static void do_state(struct net_device *dev,
560 struct can_frame *cf, enum can_state new_state)
562 struct flexcan_priv *priv = netdev_priv(dev);
563 struct can_berr_counter bec;
565 __flexcan_get_berr_counter(dev, &bec);
567 switch (priv->can.state) {
568 case CAN_STATE_ERROR_ACTIVE:
571 * to : ERROR_WARNING, ERROR_PASSIVE, BUS_OFF
572 * => : there was a warning int
574 if (new_state >= CAN_STATE_ERROR_WARNING &&
575 new_state <= CAN_STATE_BUS_OFF) {
576 netdev_dbg(dev, "Error Warning IRQ\n");
577 priv->can.can_stats.error_warning++;
579 cf->can_id |= CAN_ERR_CRTL;
580 cf->data[1] = (bec.txerr > bec.rxerr) ?
581 CAN_ERR_CRTL_TX_WARNING :
582 CAN_ERR_CRTL_RX_WARNING;
584 case CAN_STATE_ERROR_WARNING: /* fallthrough */
586 * from: ERROR_ACTIVE, ERROR_WARNING
587 * to : ERROR_PASSIVE, BUS_OFF
588 * => : error passive int
590 if (new_state >= CAN_STATE_ERROR_PASSIVE &&
591 new_state <= CAN_STATE_BUS_OFF) {
592 netdev_dbg(dev, "Error Passive IRQ\n");
593 priv->can.can_stats.error_passive++;
595 cf->can_id |= CAN_ERR_CRTL;
596 cf->data[1] = (bec.txerr > bec.rxerr) ?
597 CAN_ERR_CRTL_TX_PASSIVE :
598 CAN_ERR_CRTL_RX_PASSIVE;
601 case CAN_STATE_BUS_OFF:
602 netdev_err(dev, "BUG! "
603 "hardware recovered automatically from BUS_OFF\n");
609 /* process state changes depending on the new state */
611 case CAN_STATE_ERROR_ACTIVE:
612 netdev_dbg(dev, "Error Active\n");
613 cf->can_id |= CAN_ERR_PROT;
614 cf->data[2] = CAN_ERR_PROT_ACTIVE;
616 case CAN_STATE_BUS_OFF:
617 cf->can_id |= CAN_ERR_BUSOFF;
625 static int flexcan_poll_state(struct net_device *dev, u32 reg_esr)
627 struct flexcan_priv *priv = netdev_priv(dev);
629 struct can_frame *cf;
630 enum can_state new_state;
633 flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
634 if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
635 if (likely(!(reg_esr & (FLEXCAN_ESR_TX_WRN |
636 FLEXCAN_ESR_RX_WRN))))
637 new_state = CAN_STATE_ERROR_ACTIVE;
639 new_state = CAN_STATE_ERROR_WARNING;
640 } else if (unlikely(flt == FLEXCAN_ESR_FLT_CONF_PASSIVE))
641 new_state = CAN_STATE_ERROR_PASSIVE;
643 new_state = CAN_STATE_BUS_OFF;
645 /* state hasn't changed */
646 if (likely(new_state == priv->can.state))
649 skb = alloc_can_err_skb(dev, &cf);
653 do_state(dev, cf, new_state);
654 priv->can.state = new_state;
655 netif_receive_skb(skb);
657 dev->stats.rx_packets++;
658 dev->stats.rx_bytes += cf->can_dlc;
663 static void flexcan_read_fifo(const struct net_device *dev,
664 struct can_frame *cf)
666 const struct flexcan_priv *priv = netdev_priv(dev);
667 struct flexcan_regs __iomem *regs = priv->base;
668 struct flexcan_mb __iomem *mb = ®s->cantxfg[0];
669 u32 reg_ctrl, reg_id;
671 reg_ctrl = flexcan_read(&mb->can_ctrl);
672 reg_id = flexcan_read(&mb->can_id);
673 if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
674 cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
676 cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
678 if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
679 cf->can_id |= CAN_RTR_FLAG;
680 cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
682 *(__be32 *)(cf->data + 0) = cpu_to_be32(flexcan_read(&mb->data[0]));
683 *(__be32 *)(cf->data + 4) = cpu_to_be32(flexcan_read(&mb->data[1]));
686 flexcan_write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, ®s->iflag1);
687 flexcan_read(®s->timer);
690 static int flexcan_read_frame(struct net_device *dev)
692 struct net_device_stats *stats = &dev->stats;
693 struct can_frame *cf;
696 skb = alloc_can_skb(dev, &cf);
697 if (unlikely(!skb)) {
702 flexcan_read_fifo(dev, cf);
703 netif_receive_skb(skb);
706 stats->rx_bytes += cf->can_dlc;
708 can_led_event(dev, CAN_LED_EVENT_RX);
713 static int flexcan_poll(struct napi_struct *napi, int quota)
715 struct net_device *dev = napi->dev;
716 const struct flexcan_priv *priv = netdev_priv(dev);
717 struct flexcan_regs __iomem *regs = priv->base;
718 u32 reg_iflag1, reg_esr;
722 * The error bits are cleared on read,
723 * use saved value from irq handler.
725 reg_esr = flexcan_read(®s->esr) | priv->reg_esr;
727 /* handle state changes */
728 work_done += flexcan_poll_state(dev, reg_esr);
731 reg_iflag1 = flexcan_read(®s->iflag1);
732 while (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE &&
734 work_done += flexcan_read_frame(dev);
735 reg_iflag1 = flexcan_read(®s->iflag1);
738 /* report bus errors */
739 if (flexcan_has_and_handle_berr(priv, reg_esr) && work_done < quota)
740 work_done += flexcan_poll_bus_err(dev, reg_esr);
742 if (work_done < quota) {
745 flexcan_write(FLEXCAN_IFLAG_DEFAULT, ®s->imask1);
746 flexcan_write(priv->reg_ctrl_default, ®s->ctrl);
752 static irqreturn_t flexcan_irq(int irq, void *dev_id)
754 struct net_device *dev = dev_id;
755 struct net_device_stats *stats = &dev->stats;
756 struct flexcan_priv *priv = netdev_priv(dev);
757 struct flexcan_regs __iomem *regs = priv->base;
758 u32 reg_iflag1, reg_esr;
760 reg_iflag1 = flexcan_read(®s->iflag1);
761 reg_esr = flexcan_read(®s->esr);
762 /* ACK all bus error and state change IRQ sources */
763 if (reg_esr & FLEXCAN_ESR_ALL_INT)
764 flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, ®s->esr);
767 * schedule NAPI in case of:
770 * - bus error IRQ and bus error reporting is activated
772 if ((reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) ||
773 (reg_esr & FLEXCAN_ESR_ERR_STATE) ||
774 flexcan_has_and_handle_berr(priv, reg_esr)) {
776 * The error bits are cleared on read,
777 * save them for later use.
779 priv->reg_esr = reg_esr & FLEXCAN_ESR_ERR_BUS;
780 flexcan_write(FLEXCAN_IFLAG_DEFAULT &
781 ~FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, ®s->imask1);
782 flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
784 napi_schedule(&priv->napi);
788 if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
789 flexcan_write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW, ®s->iflag1);
790 dev->stats.rx_over_errors++;
791 dev->stats.rx_errors++;
794 /* transmission complete interrupt */
795 if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
796 stats->tx_bytes += can_get_echo_skb(dev, 0);
798 can_led_event(dev, CAN_LED_EVENT_TX);
799 flexcan_write((1 << FLEXCAN_TX_BUF_ID), ®s->iflag1);
800 netif_wake_queue(dev);
806 static void flexcan_set_bittiming(struct net_device *dev)
808 const struct flexcan_priv *priv = netdev_priv(dev);
809 const struct can_bittiming *bt = &priv->can.bittiming;
810 struct flexcan_regs __iomem *regs = priv->base;
813 reg = flexcan_read(®s->ctrl);
814 reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
815 FLEXCAN_CTRL_RJW(0x3) |
816 FLEXCAN_CTRL_PSEG1(0x7) |
817 FLEXCAN_CTRL_PSEG2(0x7) |
818 FLEXCAN_CTRL_PROPSEG(0x7) |
823 reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
824 FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
825 FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
826 FLEXCAN_CTRL_RJW(bt->sjw - 1) |
827 FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
829 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
830 reg |= FLEXCAN_CTRL_LPB;
831 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
832 reg |= FLEXCAN_CTRL_LOM;
833 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
834 reg |= FLEXCAN_CTRL_SMP;
836 netdev_info(dev, "writing ctrl=0x%08x\n", reg);
837 flexcan_write(reg, ®s->ctrl);
839 /* print chip status */
840 netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
841 flexcan_read(®s->mcr), flexcan_read(®s->ctrl));
847 * this functions is entered with clocks enabled
850 static int flexcan_chip_start(struct net_device *dev)
852 struct flexcan_priv *priv = netdev_priv(dev);
853 struct flexcan_regs __iomem *regs = priv->base;
855 u32 reg_mcr, reg_ctrl, reg_crl2, reg_mecr;
858 err = flexcan_chip_enable(priv);
863 err = flexcan_chip_softreset(priv);
865 goto out_chip_disable;
867 flexcan_set_bittiming(dev);
875 * only supervisor access
881 reg_mcr = flexcan_read(®s->mcr);
882 reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
883 reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
884 FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN |
885 FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS |
886 FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
887 netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
888 flexcan_write(reg_mcr, ®s->mcr);
893 * disable timer sync feature
895 * disable auto busoff recovery
896 * transmit lowest buffer first
898 * enable tx and rx warning interrupt
899 * enable bus off interrupt
900 * (== FLEXCAN_CTRL_ERR_STATE)
902 reg_ctrl = flexcan_read(®s->ctrl);
903 reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
904 reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
905 FLEXCAN_CTRL_ERR_STATE;
907 * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
908 * on most Flexcan cores, too. Otherwise we don't get
909 * any error warning or passive interrupts.
911 if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE ||
912 priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
913 reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
915 /* save for later use */
916 priv->reg_ctrl_default = reg_ctrl;
917 netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
918 flexcan_write(reg_ctrl, ®s->ctrl);
920 /* Abort any pending TX, mark Mailbox as INACTIVE */
921 flexcan_write(FLEXCAN_MB_CNT_CODE(0x4),
922 ®s->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
924 /* acceptance mask/acceptance code (accept everything) */
925 flexcan_write(0x0, ®s->rxgmask);
926 flexcan_write(0x0, ®s->rx14mask);
927 flexcan_write(0x0, ®s->rx15mask);
929 if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
930 flexcan_write(0x0, ®s->rxfgmask);
933 * On Vybrid, disable memory error detection interrupts
935 * This also works around errata e5295 which generates
936 * false positive memory errors and put the device in
939 if (priv->devtype_data->features & FLEXCAN_HAS_MECR_FEATURES) {
941 * Follow the protocol as described in "Detection
942 * and Correction of Memory Errors" to write to
945 reg_crl2 = flexcan_read(®s->crl2);
946 reg_crl2 |= FLEXCAN_CRL2_ECRWRE;
947 flexcan_write(reg_crl2, ®s->crl2);
949 reg_mecr = flexcan_read(®s->mecr);
950 reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
951 flexcan_write(reg_mecr, ®s->mecr);
952 reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
953 FLEXCAN_MECR_FANCEI_MSK);
954 flexcan_write(reg_mecr, ®s->mecr);
957 err = flexcan_transceiver_enable(priv);
959 goto out_chip_disable;
961 /* synchronize with the can bus */
962 err = flexcan_chip_unfreeze(priv);
964 goto out_transceiver_disable;
966 priv->can.state = CAN_STATE_ERROR_ACTIVE;
968 /* enable FIFO interrupts */
969 flexcan_write(FLEXCAN_IFLAG_DEFAULT, ®s->imask1);
971 /* print chip status */
972 netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
973 flexcan_read(®s->mcr), flexcan_read(®s->ctrl));
977 out_transceiver_disable:
978 flexcan_transceiver_disable(priv);
980 flexcan_chip_disable(priv);
987 * this functions is entered with clocks enabled
990 static void flexcan_chip_stop(struct net_device *dev)
992 struct flexcan_priv *priv = netdev_priv(dev);
993 struct flexcan_regs __iomem *regs = priv->base;
995 /* freeze + disable module */
996 flexcan_chip_freeze(priv);
997 flexcan_chip_disable(priv);
999 /* Disable all interrupts */
1000 flexcan_write(0, ®s->imask1);
1001 flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
1004 flexcan_transceiver_disable(priv);
1005 priv->can.state = CAN_STATE_STOPPED;
1010 static int flexcan_open(struct net_device *dev)
1012 struct flexcan_priv *priv = netdev_priv(dev);
1015 err = clk_prepare_enable(priv->clk_ipg);
1019 err = clk_prepare_enable(priv->clk_per);
1021 goto out_disable_ipg;
1023 err = open_candev(dev);
1025 goto out_disable_per;
1027 err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1031 /* start chip and queuing */
1032 err = flexcan_chip_start(dev);
1036 can_led_event(dev, CAN_LED_EVENT_OPEN);
1038 napi_enable(&priv->napi);
1039 netif_start_queue(dev);
1044 free_irq(dev->irq, dev);
1048 clk_disable_unprepare(priv->clk_per);
1050 clk_disable_unprepare(priv->clk_ipg);
1055 static int flexcan_close(struct net_device *dev)
1057 struct flexcan_priv *priv = netdev_priv(dev);
1059 netif_stop_queue(dev);
1060 napi_disable(&priv->napi);
1061 flexcan_chip_stop(dev);
1063 free_irq(dev->irq, dev);
1064 clk_disable_unprepare(priv->clk_per);
1065 clk_disable_unprepare(priv->clk_ipg);
1069 can_led_event(dev, CAN_LED_EVENT_STOP);
1074 static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1079 case CAN_MODE_START:
1080 err = flexcan_chip_start(dev);
1084 netif_wake_queue(dev);
1094 static const struct net_device_ops flexcan_netdev_ops = {
1095 .ndo_open = flexcan_open,
1096 .ndo_stop = flexcan_close,
1097 .ndo_start_xmit = flexcan_start_xmit,
1098 .ndo_change_mtu = can_change_mtu,
1101 static int register_flexcandev(struct net_device *dev)
1103 struct flexcan_priv *priv = netdev_priv(dev);
1104 struct flexcan_regs __iomem *regs = priv->base;
1107 err = clk_prepare_enable(priv->clk_ipg);
1111 err = clk_prepare_enable(priv->clk_per);
1113 goto out_disable_ipg;
1115 /* select "bus clock", chip must be disabled */
1116 err = flexcan_chip_disable(priv);
1118 goto out_disable_per;
1119 reg = flexcan_read(®s->ctrl);
1120 reg |= FLEXCAN_CTRL_CLK_SRC;
1121 flexcan_write(reg, ®s->ctrl);
1123 err = flexcan_chip_enable(priv);
1125 goto out_chip_disable;
1127 /* set freeze, halt and activate FIFO, restrict register access */
1128 reg = flexcan_read(®s->mcr);
1129 reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
1130 FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1131 flexcan_write(reg, ®s->mcr);
1134 * Currently we only support newer versions of this core
1135 * featuring a RX FIFO. Older cores found on some Coldfire
1136 * derivates are not yet supported.
1138 reg = flexcan_read(®s->mcr);
1139 if (!(reg & FLEXCAN_MCR_FEN)) {
1140 netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1142 goto out_chip_disable;
1145 err = register_candev(dev);
1147 /* disable core and turn off clocks */
1149 flexcan_chip_disable(priv);
1151 clk_disable_unprepare(priv->clk_per);
1153 clk_disable_unprepare(priv->clk_ipg);
1158 static void unregister_flexcandev(struct net_device *dev)
1160 unregister_candev(dev);
1163 static const struct of_device_id flexcan_of_match[] = {
1164 { .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
1165 { .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
1166 { .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
1167 { .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
1170 MODULE_DEVICE_TABLE(of, flexcan_of_match);
1172 static const struct platform_device_id flexcan_id_table[] = {
1173 { .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
1176 MODULE_DEVICE_TABLE(platform, flexcan_id_table);
1178 static int flexcan_probe(struct platform_device *pdev)
1180 const struct of_device_id *of_id;
1181 const struct flexcan_devtype_data *devtype_data;
1182 struct net_device *dev;
1183 struct flexcan_priv *priv;
1184 struct resource *mem;
1185 struct clk *clk_ipg = NULL, *clk_per = NULL;
1190 if (pdev->dev.of_node)
1191 of_property_read_u32(pdev->dev.of_node,
1192 "clock-frequency", &clock_freq);
1195 clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1196 if (IS_ERR(clk_ipg)) {
1197 dev_err(&pdev->dev, "no ipg clock defined\n");
1198 return PTR_ERR(clk_ipg);
1201 clk_per = devm_clk_get(&pdev->dev, "per");
1202 if (IS_ERR(clk_per)) {
1203 dev_err(&pdev->dev, "no per clock defined\n");
1204 return PTR_ERR(clk_per);
1206 clock_freq = clk_get_rate(clk_per);
1209 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1210 irq = platform_get_irq(pdev, 0);
1214 base = devm_ioremap_resource(&pdev->dev, mem);
1216 return PTR_ERR(base);
1218 of_id = of_match_device(flexcan_of_match, &pdev->dev);
1220 devtype_data = of_id->data;
1221 } else if (platform_get_device_id(pdev)->driver_data) {
1222 devtype_data = (struct flexcan_devtype_data *)
1223 platform_get_device_id(pdev)->driver_data;
1228 dev = alloc_candev(sizeof(struct flexcan_priv), 1);
1232 dev->netdev_ops = &flexcan_netdev_ops;
1234 dev->flags |= IFF_ECHO;
1236 priv = netdev_priv(dev);
1237 priv->can.clock.freq = clock_freq;
1238 priv->can.bittiming_const = &flexcan_bittiming_const;
1239 priv->can.do_set_mode = flexcan_set_mode;
1240 priv->can.do_get_berr_counter = flexcan_get_berr_counter;
1241 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1242 CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_3_SAMPLES |
1243 CAN_CTRLMODE_BERR_REPORTING;
1246 priv->clk_ipg = clk_ipg;
1247 priv->clk_per = clk_per;
1248 priv->pdata = dev_get_platdata(&pdev->dev);
1249 priv->devtype_data = devtype_data;
1251 priv->reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
1252 if (IS_ERR(priv->reg_xceiver))
1253 priv->reg_xceiver = NULL;
1255 netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);
1257 platform_set_drvdata(pdev, dev);
1258 SET_NETDEV_DEV(dev, &pdev->dev);
1260 err = register_flexcandev(dev);
1262 dev_err(&pdev->dev, "registering netdev failed\n");
1263 goto failed_register;
1266 devm_can_led_init(dev);
1268 dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
1269 priv->base, dev->irq);
1278 static int flexcan_remove(struct platform_device *pdev)
1280 struct net_device *dev = platform_get_drvdata(pdev);
1281 struct flexcan_priv *priv = netdev_priv(dev);
1283 unregister_flexcandev(dev);
1284 netif_napi_del(&priv->napi);
1290 static int __maybe_unused flexcan_suspend(struct device *device)
1292 struct net_device *dev = dev_get_drvdata(device);
1293 struct flexcan_priv *priv = netdev_priv(dev);
1296 err = flexcan_chip_disable(priv);
1300 if (netif_running(dev)) {
1301 netif_stop_queue(dev);
1302 netif_device_detach(dev);
1304 priv->can.state = CAN_STATE_SLEEPING;
1309 static int __maybe_unused flexcan_resume(struct device *device)
1311 struct net_device *dev = dev_get_drvdata(device);
1312 struct flexcan_priv *priv = netdev_priv(dev);
1314 priv->can.state = CAN_STATE_ERROR_ACTIVE;
1315 if (netif_running(dev)) {
1316 netif_device_attach(dev);
1317 netif_start_queue(dev);
1319 return flexcan_chip_enable(priv);
1322 static SIMPLE_DEV_PM_OPS(flexcan_pm_ops, flexcan_suspend, flexcan_resume);
1324 static struct platform_driver flexcan_driver = {
1327 .owner = THIS_MODULE,
1328 .pm = &flexcan_pm_ops,
1329 .of_match_table = flexcan_of_match,
1331 .probe = flexcan_probe,
1332 .remove = flexcan_remove,
1333 .id_table = flexcan_id_table,
1336 module_platform_driver(flexcan_driver);
1338 MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
1339 "Marc Kleine-Budde <kernel@pengutronix.de>");
1340 MODULE_LICENSE("GPL v2");
1341 MODULE_DESCRIPTION("CAN port driver for flexcan based chip");