1 // SPDX-License-Identifier: GPL-2.0
2 // CAN bus driver for Bosch M_CAN controller
3 // Copyright (C) 2014 Freescale Semiconductor, Inc.
4 // Dong Aisheng <b29396@freescale.com>
5 // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
7 /* Bosch M_CAN user manual can be obtained from:
8 * https://github.com/linux-can/can-doc/tree/master/m_can
11 #include <linux/bitfield.h>
12 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
18 #include <linux/of_device.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/iopoll.h>
22 #include <linux/can/dev.h>
23 #include <linux/pinctrl/consumer.h>
27 /* registers definition */
43 /* TDCR Register only available for version >=3.1.x */
80 #define M_CAN_NAPI_WEIGHT 64
82 /* message ram configuration data length */
83 #define MRAM_CFG_LEN 8
85 /* Core Release Register (CREL) */
86 #define CREL_REL_MASK GENMASK(31, 28)
87 #define CREL_STEP_MASK GENMASK(27, 24)
88 #define CREL_SUBSTEP_MASK GENMASK(23, 20)
90 /* Data Bit Timing & Prescaler Register (DBTP) */
91 #define DBTP_TDC BIT(23)
92 #define DBTP_DBRP_MASK GENMASK(20, 16)
93 #define DBTP_DTSEG1_MASK GENMASK(12, 8)
94 #define DBTP_DTSEG2_MASK GENMASK(7, 4)
95 #define DBTP_DSJW_MASK GENMASK(3, 0)
97 /* Transmitter Delay Compensation Register (TDCR) */
98 #define TDCR_TDCO_MASK GENMASK(14, 8)
99 #define TDCR_TDCF_MASK GENMASK(6, 0)
101 /* Test Register (TEST) */
102 #define TEST_LBCK BIT(4)
104 /* CC Control Register (CCCR) */
105 #define CCCR_TXP BIT(14)
106 #define CCCR_TEST BIT(7)
107 #define CCCR_DAR BIT(6)
108 #define CCCR_MON BIT(5)
109 #define CCCR_CSR BIT(4)
110 #define CCCR_CSA BIT(3)
111 #define CCCR_ASM BIT(2)
112 #define CCCR_CCE BIT(1)
113 #define CCCR_INIT BIT(0)
114 /* for version 3.0.x */
115 #define CCCR_CMR_MASK GENMASK(11, 10)
116 #define CCCR_CMR_CANFD 0x1
117 #define CCCR_CMR_CANFD_BRS 0x2
118 #define CCCR_CMR_CAN 0x3
119 #define CCCR_CME_MASK GENMASK(9, 8)
120 #define CCCR_CME_CAN 0
121 #define CCCR_CME_CANFD 0x1
122 #define CCCR_CME_CANFD_BRS 0x2
123 /* for version >=3.1.x */
124 #define CCCR_EFBI BIT(13)
125 #define CCCR_PXHD BIT(12)
126 #define CCCR_BRSE BIT(9)
127 #define CCCR_FDOE BIT(8)
128 /* for version >=3.2.x */
129 #define CCCR_NISO BIT(15)
130 /* for version >=3.3.x */
131 #define CCCR_WMM BIT(11)
132 #define CCCR_UTSU BIT(10)
134 /* Nominal Bit Timing & Prescaler Register (NBTP) */
135 #define NBTP_NSJW_MASK GENMASK(31, 25)
136 #define NBTP_NBRP_MASK GENMASK(24, 16)
137 #define NBTP_NTSEG1_MASK GENMASK(15, 8)
138 #define NBTP_NTSEG2_MASK GENMASK(6, 0)
140 /* Timestamp Counter Configuration Register (TSCC) */
141 #define TSCC_TCP_MASK GENMASK(19, 16)
142 #define TSCC_TSS_MASK GENMASK(1, 0)
143 #define TSCC_TSS_DISABLE 0x0
144 #define TSCC_TSS_INTERNAL 0x1
145 #define TSCC_TSS_EXTERNAL 0x2
147 /* Timestamp Counter Value Register (TSCV) */
148 #define TSCV_TSC_MASK GENMASK(15, 0)
150 /* Error Counter Register (ECR) */
151 #define ECR_RP BIT(15)
152 #define ECR_REC_MASK GENMASK(14, 8)
153 #define ECR_TEC_MASK GENMASK(7, 0)
155 /* Protocol Status Register (PSR) */
156 #define PSR_BO BIT(7)
157 #define PSR_EW BIT(6)
158 #define PSR_EP BIT(5)
159 #define PSR_LEC_MASK GENMASK(2, 0)
161 /* Interrupt Register (IR) */
162 #define IR_ALL_INT 0xffffffff
164 /* Renamed bits for versions > 3.1.x */
165 #define IR_ARA BIT(29)
166 #define IR_PED BIT(28)
167 #define IR_PEA BIT(27)
169 /* Bits for version 3.0.x */
170 #define IR_STE BIT(31)
171 #define IR_FOE BIT(30)
172 #define IR_ACKE BIT(29)
173 #define IR_BE BIT(28)
174 #define IR_CRCE BIT(27)
175 #define IR_WDI BIT(26)
176 #define IR_BO BIT(25)
177 #define IR_EW BIT(24)
178 #define IR_EP BIT(23)
179 #define IR_ELO BIT(22)
180 #define IR_BEU BIT(21)
181 #define IR_BEC BIT(20)
182 #define IR_DRX BIT(19)
183 #define IR_TOO BIT(18)
184 #define IR_MRAF BIT(17)
185 #define IR_TSW BIT(16)
186 #define IR_TEFL BIT(15)
187 #define IR_TEFF BIT(14)
188 #define IR_TEFW BIT(13)
189 #define IR_TEFN BIT(12)
190 #define IR_TFE BIT(11)
191 #define IR_TCF BIT(10)
193 #define IR_HPM BIT(8)
194 #define IR_RF1L BIT(7)
195 #define IR_RF1F BIT(6)
196 #define IR_RF1W BIT(5)
197 #define IR_RF1N BIT(4)
198 #define IR_RF0L BIT(3)
199 #define IR_RF0F BIT(2)
200 #define IR_RF0W BIT(1)
201 #define IR_RF0N BIT(0)
202 #define IR_ERR_STATE (IR_BO | IR_EW | IR_EP)
204 /* Interrupts for version 3.0.x */
205 #define IR_ERR_LEC_30X (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
206 #define IR_ERR_BUS_30X (IR_ERR_LEC_30X | IR_WDI | IR_ELO | IR_BEU | \
207 IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
209 #define IR_ERR_ALL_30X (IR_ERR_STATE | IR_ERR_BUS_30X)
211 /* Interrupts for version >= 3.1.x */
212 #define IR_ERR_LEC_31X (IR_PED | IR_PEA)
213 #define IR_ERR_BUS_31X (IR_ERR_LEC_31X | IR_WDI | IR_ELO | IR_BEU | \
214 IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
216 #define IR_ERR_ALL_31X (IR_ERR_STATE | IR_ERR_BUS_31X)
218 /* Interrupt Line Select (ILS) */
219 #define ILS_ALL_INT0 0x0
220 #define ILS_ALL_INT1 0xFFFFFFFF
222 /* Interrupt Line Enable (ILE) */
223 #define ILE_EINT1 BIT(1)
224 #define ILE_EINT0 BIT(0)
226 /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
227 #define RXFC_FWM_MASK GENMASK(30, 24)
228 #define RXFC_FS_MASK GENMASK(22, 16)
230 /* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
231 #define RXFS_RFL BIT(25)
232 #define RXFS_FF BIT(24)
233 #define RXFS_FPI_MASK GENMASK(21, 16)
234 #define RXFS_FGI_MASK GENMASK(13, 8)
235 #define RXFS_FFL_MASK GENMASK(6, 0)
237 /* Rx Buffer / FIFO Element Size Configuration (RXESC) */
238 #define RXESC_RBDS_MASK GENMASK(10, 8)
239 #define RXESC_F1DS_MASK GENMASK(6, 4)
240 #define RXESC_F0DS_MASK GENMASK(2, 0)
241 #define RXESC_64B 0x7
243 /* Tx Buffer Configuration (TXBC) */
244 #define TXBC_TFQS_MASK GENMASK(29, 24)
245 #define TXBC_NDTB_MASK GENMASK(21, 16)
247 /* Tx FIFO/Queue Status (TXFQS) */
248 #define TXFQS_TFQF BIT(21)
249 #define TXFQS_TFQPI_MASK GENMASK(20, 16)
250 #define TXFQS_TFGI_MASK GENMASK(12, 8)
251 #define TXFQS_TFFL_MASK GENMASK(5, 0)
253 /* Tx Buffer Element Size Configuration (TXESC) */
254 #define TXESC_TBDS_MASK GENMASK(2, 0)
255 #define TXESC_TBDS_64B 0x7
257 /* Tx Event FIFO Configuration (TXEFC) */
258 #define TXEFC_EFS_MASK GENMASK(21, 16)
260 /* Tx Event FIFO Status (TXEFS) */
261 #define TXEFS_TEFL BIT(25)
262 #define TXEFS_EFF BIT(24)
263 #define TXEFS_EFGI_MASK GENMASK(12, 8)
264 #define TXEFS_EFFL_MASK GENMASK(5, 0)
266 /* Tx Event FIFO Acknowledge (TXEFA) */
267 #define TXEFA_EFAI_MASK GENMASK(4, 0)
269 /* Message RAM Configuration (in bytes) */
270 #define SIDF_ELEMENT_SIZE 4
271 #define XIDF_ELEMENT_SIZE 8
272 #define RXF0_ELEMENT_SIZE 72
273 #define RXF1_ELEMENT_SIZE 72
274 #define RXB_ELEMENT_SIZE 72
275 #define TXE_ELEMENT_SIZE 8
276 #define TXB_ELEMENT_SIZE 72
278 /* Message RAM Elements */
279 #define M_CAN_FIFO_ID 0x0
280 #define M_CAN_FIFO_DLC 0x4
281 #define M_CAN_FIFO_DATA(n) (0x8 + ((n) << 2))
283 /* Rx Buffer Element */
285 #define RX_BUF_ESI BIT(31)
286 #define RX_BUF_XTD BIT(30)
287 #define RX_BUF_RTR BIT(29)
289 #define RX_BUF_ANMF BIT(31)
290 #define RX_BUF_FDF BIT(21)
291 #define RX_BUF_BRS BIT(20)
292 #define RX_BUF_RXTS_MASK GENMASK(15, 0)
294 /* Tx Buffer Element */
296 #define TX_BUF_ESI BIT(31)
297 #define TX_BUF_XTD BIT(30)
298 #define TX_BUF_RTR BIT(29)
300 #define TX_BUF_EFC BIT(23)
301 #define TX_BUF_FDF BIT(21)
302 #define TX_BUF_BRS BIT(20)
303 #define TX_BUF_MM_MASK GENMASK(31, 24)
304 #define TX_BUF_DLC_MASK GENMASK(19, 16)
306 /* Tx event FIFO Element */
308 #define TX_EVENT_MM_MASK GENMASK(31, 24)
309 #define TX_EVENT_TXTS_MASK GENMASK(15, 0)
311 static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg)
313 return cdev->ops->read_reg(cdev, reg);
316 static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg,
319 cdev->ops->write_reg(cdev, reg, val);
322 static u32 m_can_fifo_read(struct m_can_classdev *cdev,
323 u32 fgi, unsigned int offset)
325 u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE +
328 return cdev->ops->read_fifo(cdev, addr_offset);
331 static void m_can_fifo_write(struct m_can_classdev *cdev,
332 u32 fpi, unsigned int offset, u32 val)
334 u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE +
337 cdev->ops->write_fifo(cdev, addr_offset, val);
340 static inline void m_can_fifo_write_no_off(struct m_can_classdev *cdev,
343 cdev->ops->write_fifo(cdev, fpi, val);
346 static u32 m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset)
348 u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE +
351 return cdev->ops->read_fifo(cdev, addr_offset);
354 static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev)
356 return !!(m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQF);
359 static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
361 u32 cccr = m_can_read(cdev, M_CAN_CCCR);
365 /* Clear the Clock stop request if it was set */
370 /* enable m_can configuration */
371 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT);
373 /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
374 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
376 m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
379 /* there's a delay for module initialization */
381 val = CCCR_INIT | CCCR_CCE;
383 while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
385 netdev_warn(cdev->net, "Failed to init module\n");
393 static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev)
395 /* Only interrupt line 0 is used in this driver */
396 m_can_write(cdev, M_CAN_ILE, ILE_EINT0);
399 static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev)
401 m_can_write(cdev, M_CAN_ILE, 0x0);
404 /* Retrieve internal timestamp counter from TSCV.TSC, and shift it to 32-bit
407 static u32 m_can_get_timestamp(struct m_can_classdev *cdev)
412 tscv = m_can_read(cdev, M_CAN_TSCV);
413 tsc = FIELD_GET(TSCV_TSC_MASK, tscv);
418 static void m_can_clean(struct net_device *net)
420 struct m_can_classdev *cdev = netdev_priv(net);
425 net->stats.tx_errors++;
426 if (cdev->version > 30)
427 putidx = FIELD_GET(TXFQS_TFQPI_MASK,
428 m_can_read(cdev, M_CAN_TXFQS));
430 can_free_echo_skb(cdev->net, putidx, NULL);
435 /* For peripherals, pass skb to rx-offload, which will push skb from
436 * napi. For non-peripherals, RX is done in napi already, so push
437 * directly. timestamp is used to ensure good skb ordering in
438 * rx-offload and is ignored for non-peripherals.
440 static void m_can_receive_skb(struct m_can_classdev *cdev,
444 if (cdev->is_peripheral) {
445 struct net_device_stats *stats = &cdev->net->stats;
448 err = can_rx_offload_queue_sorted(&cdev->offload, skb,
451 stats->rx_fifo_errors++;
453 netif_receive_skb(skb);
457 static void m_can_read_fifo(struct net_device *dev, u32 rxfs)
459 struct net_device_stats *stats = &dev->stats;
460 struct m_can_classdev *cdev = netdev_priv(dev);
461 struct canfd_frame *cf;
467 /* calculate the fifo get index for where to read data */
468 fgi = FIELD_GET(RXFS_FGI_MASK, rxfs);
469 dlc = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DLC);
470 if (dlc & RX_BUF_FDF)
471 skb = alloc_canfd_skb(dev, &cf);
473 skb = alloc_can_skb(dev, (struct can_frame **)&cf);
479 if (dlc & RX_BUF_FDF)
480 cf->len = can_fd_dlc2len((dlc >> 16) & 0x0F);
482 cf->len = can_cc_dlc2len((dlc >> 16) & 0x0F);
484 id = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID);
486 cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
488 cf->can_id = (id >> 18) & CAN_SFF_MASK;
490 if (id & RX_BUF_ESI) {
491 cf->flags |= CANFD_ESI;
492 netdev_dbg(dev, "ESI Error\n");
495 if (!(dlc & RX_BUF_FDF) && (id & RX_BUF_RTR)) {
496 cf->can_id |= CAN_RTR_FLAG;
498 if (dlc & RX_BUF_BRS)
499 cf->flags |= CANFD_BRS;
501 for (i = 0; i < cf->len; i += 4)
502 *(u32 *)(cf->data + i) =
503 m_can_fifo_read(cdev, fgi,
504 M_CAN_FIFO_DATA(i / 4));
507 /* acknowledge rx fifo 0 */
508 m_can_write(cdev, M_CAN_RXF0A, fgi);
511 stats->rx_bytes += cf->len;
513 timestamp = FIELD_GET(RX_BUF_RXTS_MASK, dlc);
515 m_can_receive_skb(cdev, skb, timestamp);
518 static int m_can_do_rx_poll(struct net_device *dev, int quota)
520 struct m_can_classdev *cdev = netdev_priv(dev);
524 rxfs = m_can_read(cdev, M_CAN_RXF0S);
525 if (!(rxfs & RXFS_FFL_MASK)) {
526 netdev_dbg(dev, "no messages in fifo0\n");
530 while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
531 m_can_read_fifo(dev, rxfs);
535 rxfs = m_can_read(cdev, M_CAN_RXF0S);
539 can_led_event(dev, CAN_LED_EVENT_RX);
544 static int m_can_handle_lost_msg(struct net_device *dev)
546 struct m_can_classdev *cdev = netdev_priv(dev);
547 struct net_device_stats *stats = &dev->stats;
549 struct can_frame *frame;
552 netdev_err(dev, "msg lost in rxf0\n");
555 stats->rx_over_errors++;
557 skb = alloc_can_err_skb(dev, &frame);
561 frame->can_id |= CAN_ERR_CRTL;
562 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
564 if (cdev->is_peripheral)
565 timestamp = m_can_get_timestamp(cdev);
567 m_can_receive_skb(cdev, skb, timestamp);
572 static int m_can_handle_lec_err(struct net_device *dev,
573 enum m_can_lec_type lec_type)
575 struct m_can_classdev *cdev = netdev_priv(dev);
576 struct net_device_stats *stats = &dev->stats;
577 struct can_frame *cf;
581 cdev->can.can_stats.bus_error++;
584 /* propagate the error condition to the CAN stack */
585 skb = alloc_can_err_skb(dev, &cf);
589 /* check for 'last error code' which tells us the
590 * type of the last error to occur on the CAN bus
592 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
595 case LEC_STUFF_ERROR:
596 netdev_dbg(dev, "stuff error\n");
597 cf->data[2] |= CAN_ERR_PROT_STUFF;
600 netdev_dbg(dev, "form error\n");
601 cf->data[2] |= CAN_ERR_PROT_FORM;
604 netdev_dbg(dev, "ack error\n");
605 cf->data[3] = CAN_ERR_PROT_LOC_ACK;
608 netdev_dbg(dev, "bit1 error\n");
609 cf->data[2] |= CAN_ERR_PROT_BIT1;
612 netdev_dbg(dev, "bit0 error\n");
613 cf->data[2] |= CAN_ERR_PROT_BIT0;
616 netdev_dbg(dev, "CRC error\n");
617 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
624 stats->rx_bytes += cf->len;
626 if (cdev->is_peripheral)
627 timestamp = m_can_get_timestamp(cdev);
629 m_can_receive_skb(cdev, skb, timestamp);
634 static int __m_can_get_berr_counter(const struct net_device *dev,
635 struct can_berr_counter *bec)
637 struct m_can_classdev *cdev = netdev_priv(dev);
640 ecr = m_can_read(cdev, M_CAN_ECR);
641 bec->rxerr = FIELD_GET(ECR_REC_MASK, ecr);
642 bec->txerr = FIELD_GET(ECR_TEC_MASK, ecr);
647 static int m_can_clk_start(struct m_can_classdev *cdev)
649 if (cdev->pm_clock_support == 0)
652 return pm_runtime_resume_and_get(cdev->dev);
655 static void m_can_clk_stop(struct m_can_classdev *cdev)
657 if (cdev->pm_clock_support)
658 pm_runtime_put_sync(cdev->dev);
661 static int m_can_get_berr_counter(const struct net_device *dev,
662 struct can_berr_counter *bec)
664 struct m_can_classdev *cdev = netdev_priv(dev);
667 err = m_can_clk_start(cdev);
671 __m_can_get_berr_counter(dev, bec);
673 m_can_clk_stop(cdev);
678 static int m_can_handle_state_change(struct net_device *dev,
679 enum can_state new_state)
681 struct m_can_classdev *cdev = netdev_priv(dev);
682 struct net_device_stats *stats = &dev->stats;
683 struct can_frame *cf;
685 struct can_berr_counter bec;
690 case CAN_STATE_ERROR_WARNING:
691 /* error warning state */
692 cdev->can.can_stats.error_warning++;
693 cdev->can.state = CAN_STATE_ERROR_WARNING;
695 case CAN_STATE_ERROR_PASSIVE:
696 /* error passive state */
697 cdev->can.can_stats.error_passive++;
698 cdev->can.state = CAN_STATE_ERROR_PASSIVE;
700 case CAN_STATE_BUS_OFF:
702 cdev->can.state = CAN_STATE_BUS_OFF;
703 m_can_disable_all_interrupts(cdev);
704 cdev->can.can_stats.bus_off++;
711 /* propagate the error condition to the CAN stack */
712 skb = alloc_can_err_skb(dev, &cf);
716 __m_can_get_berr_counter(dev, &bec);
719 case CAN_STATE_ERROR_WARNING:
720 /* error warning state */
721 cf->can_id |= CAN_ERR_CRTL;
722 cf->data[1] = (bec.txerr > bec.rxerr) ?
723 CAN_ERR_CRTL_TX_WARNING :
724 CAN_ERR_CRTL_RX_WARNING;
725 cf->data[6] = bec.txerr;
726 cf->data[7] = bec.rxerr;
728 case CAN_STATE_ERROR_PASSIVE:
729 /* error passive state */
730 cf->can_id |= CAN_ERR_CRTL;
731 ecr = m_can_read(cdev, M_CAN_ECR);
733 cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
735 cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
736 cf->data[6] = bec.txerr;
737 cf->data[7] = bec.rxerr;
739 case CAN_STATE_BUS_OFF:
741 cf->can_id |= CAN_ERR_BUSOFF;
748 stats->rx_bytes += cf->len;
750 if (cdev->is_peripheral)
751 timestamp = m_can_get_timestamp(cdev);
753 m_can_receive_skb(cdev, skb, timestamp);
758 static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
760 struct m_can_classdev *cdev = netdev_priv(dev);
763 if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) {
764 netdev_dbg(dev, "entered error warning state\n");
765 work_done += m_can_handle_state_change(dev,
766 CAN_STATE_ERROR_WARNING);
769 if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) {
770 netdev_dbg(dev, "entered error passive state\n");
771 work_done += m_can_handle_state_change(dev,
772 CAN_STATE_ERROR_PASSIVE);
775 if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) {
776 netdev_dbg(dev, "entered error bus off state\n");
777 work_done += m_can_handle_state_change(dev,
784 static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
786 if (irqstatus & IR_WDI)
787 netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
788 if (irqstatus & IR_ELO)
789 netdev_err(dev, "Error Logging Overflow\n");
790 if (irqstatus & IR_BEU)
791 netdev_err(dev, "Bit Error Uncorrected\n");
792 if (irqstatus & IR_BEC)
793 netdev_err(dev, "Bit Error Corrected\n");
794 if (irqstatus & IR_TOO)
795 netdev_err(dev, "Timeout reached\n");
796 if (irqstatus & IR_MRAF)
797 netdev_err(dev, "Message RAM access failure occurred\n");
800 static inline bool is_lec_err(u32 psr)
804 return psr && (psr != LEC_UNUSED);
807 static inline bool m_can_is_protocol_err(u32 irqstatus)
809 return irqstatus & IR_ERR_LEC_31X;
812 static int m_can_handle_protocol_error(struct net_device *dev, u32 irqstatus)
814 struct net_device_stats *stats = &dev->stats;
815 struct m_can_classdev *cdev = netdev_priv(dev);
816 struct can_frame *cf;
820 /* propagate the error condition to the CAN stack */
821 skb = alloc_can_err_skb(dev, &cf);
823 /* update tx error stats since there is protocol error */
826 /* update arbitration lost status */
827 if (cdev->version >= 31 && (irqstatus & IR_PEA)) {
828 netdev_dbg(dev, "Protocol error in Arbitration fail\n");
829 cdev->can.can_stats.arbitration_lost++;
831 cf->can_id |= CAN_ERR_LOSTARB;
832 cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC;
836 if (unlikely(!skb)) {
837 netdev_dbg(dev, "allocation of skb failed\n");
841 if (cdev->is_peripheral)
842 timestamp = m_can_get_timestamp(cdev);
844 m_can_receive_skb(cdev, skb, timestamp);
849 static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
852 struct m_can_classdev *cdev = netdev_priv(dev);
855 if (irqstatus & IR_RF0L)
856 work_done += m_can_handle_lost_msg(dev);
858 /* handle lec errors on the bus */
859 if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
861 work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);
863 /* handle protocol errors in arbitration phase */
864 if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
865 m_can_is_protocol_err(irqstatus))
866 work_done += m_can_handle_protocol_error(dev, irqstatus);
868 /* other unproccessed error interrupts */
869 m_can_handle_other_err(dev, irqstatus);
874 static int m_can_rx_handler(struct net_device *dev, int quota)
876 struct m_can_classdev *cdev = netdev_priv(dev);
880 irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR);
884 /* Errata workaround for issue "Needless activation of MRAF irq"
885 * During frame reception while the MCAN is in Error Passive state
886 * and the Receive Error Counter has the value MCAN_ECR.REC = 127,
887 * it may happen that MCAN_IR.MRAF is set although there was no
888 * Message RAM access failure.
889 * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated
890 * The Message RAM Access Failure interrupt routine needs to check
891 * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127.
892 * In this case, reset MCAN_IR.MRAF. No further action is required.
894 if (cdev->version <= 31 && irqstatus & IR_MRAF &&
895 m_can_read(cdev, M_CAN_ECR) & ECR_RP) {
896 struct can_berr_counter bec;
898 __m_can_get_berr_counter(dev, &bec);
899 if (bec.rxerr == 127) {
900 m_can_write(cdev, M_CAN_IR, IR_MRAF);
901 irqstatus &= ~IR_MRAF;
905 psr = m_can_read(cdev, M_CAN_PSR);
907 if (irqstatus & IR_ERR_STATE)
908 work_done += m_can_handle_state_errors(dev, psr);
910 if (irqstatus & IR_ERR_BUS_30X)
911 work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
913 if (irqstatus & IR_RF0N)
914 work_done += m_can_do_rx_poll(dev, (quota - work_done));
919 static int m_can_rx_peripheral(struct net_device *dev)
921 struct m_can_classdev *cdev = netdev_priv(dev);
923 m_can_rx_handler(dev, M_CAN_NAPI_WEIGHT);
925 m_can_enable_all_interrupts(cdev);
930 static int m_can_poll(struct napi_struct *napi, int quota)
932 struct net_device *dev = napi->dev;
933 struct m_can_classdev *cdev = netdev_priv(dev);
936 work_done = m_can_rx_handler(dev, quota);
937 if (work_done < quota) {
938 napi_complete_done(napi, work_done);
939 m_can_enable_all_interrupts(cdev);
945 /* Echo tx skb and update net stats. Peripherals use rx-offload for
946 * echo. timestamp is used for peripherals to ensure correct ordering
947 * by rx-offload, and is ignored for non-peripherals.
949 static void m_can_tx_update_stats(struct m_can_classdev *cdev,
950 unsigned int msg_mark,
953 struct net_device *dev = cdev->net;
954 struct net_device_stats *stats = &dev->stats;
956 if (cdev->is_peripheral)
958 can_rx_offload_get_echo_skb(&cdev->offload,
963 stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL);
968 static void m_can_echo_tx_event(struct net_device *dev)
974 unsigned int msg_mark;
976 struct m_can_classdev *cdev = netdev_priv(dev);
978 /* read tx event fifo status */
979 m_can_txefs = m_can_read(cdev, M_CAN_TXEFS);
981 /* Get Tx Event fifo element count */
982 txe_count = FIELD_GET(TXEFS_EFFL_MASK, m_can_txefs);
984 /* Get and process all sent elements */
985 for (i = 0; i < txe_count; i++) {
986 u32 txe, timestamp = 0;
988 /* retrieve get index */
989 fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_read(cdev, M_CAN_TXEFS));
991 /* get message marker, timestamp */
992 txe = m_can_txe_fifo_read(cdev, fgi, 4);
993 msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe);
994 timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe);
996 /* ack txe element */
997 m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK,
1001 m_can_tx_update_stats(cdev, msg_mark, timestamp);
1005 static irqreturn_t m_can_isr(int irq, void *dev_id)
1007 struct net_device *dev = (struct net_device *)dev_id;
1008 struct m_can_classdev *cdev = netdev_priv(dev);
1011 if (pm_runtime_suspended(cdev->dev))
1013 ir = m_can_read(cdev, M_CAN_IR);
1018 if (ir & IR_ALL_INT)
1019 m_can_write(cdev, M_CAN_IR, ir);
1021 if (cdev->ops->clear_interrupts)
1022 cdev->ops->clear_interrupts(cdev);
1024 /* schedule NAPI in case of
1026 * - state change IRQ
1027 * - bus error IRQ and bus error reporting
1029 if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
1030 cdev->irqstatus = ir;
1031 m_can_disable_all_interrupts(cdev);
1032 if (!cdev->is_peripheral)
1033 napi_schedule(&cdev->napi);
1035 m_can_rx_peripheral(dev);
1038 if (cdev->version == 30) {
1040 /* Transmission Complete Interrupt*/
1043 if (cdev->is_peripheral)
1044 timestamp = m_can_get_timestamp(cdev);
1045 m_can_tx_update_stats(cdev, 0, timestamp);
1047 can_led_event(dev, CAN_LED_EVENT_TX);
1048 netif_wake_queue(dev);
1052 /* New TX FIFO Element arrived */
1053 m_can_echo_tx_event(dev);
1054 can_led_event(dev, CAN_LED_EVENT_TX);
1055 if (netif_queue_stopped(dev) &&
1056 !m_can_tx_fifo_full(cdev))
1057 netif_wake_queue(dev);
1064 static const struct can_bittiming_const m_can_bittiming_const_30X = {
1065 .name = KBUILD_MODNAME,
1066 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1068 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1076 static const struct can_bittiming_const m_can_data_bittiming_const_30X = {
1077 .name = KBUILD_MODNAME,
1078 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1080 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1088 static const struct can_bittiming_const m_can_bittiming_const_31X = {
1089 .name = KBUILD_MODNAME,
1090 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1092 .tseg2_min = 2, /* Time segment 2 = phase_seg2 */
1100 static const struct can_bittiming_const m_can_data_bittiming_const_31X = {
1101 .name = KBUILD_MODNAME,
1102 .tseg1_min = 1, /* Time segment 1 = prop_seg + phase_seg1 */
1104 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1112 static int m_can_set_bittiming(struct net_device *dev)
1114 struct m_can_classdev *cdev = netdev_priv(dev);
1115 const struct can_bittiming *bt = &cdev->can.bittiming;
1116 const struct can_bittiming *dbt = &cdev->can.data_bittiming;
1117 u16 brp, sjw, tseg1, tseg2;
1122 tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
1123 tseg2 = bt->phase_seg2 - 1;
1124 reg_btp = FIELD_PREP(NBTP_NBRP_MASK, brp) |
1125 FIELD_PREP(NBTP_NSJW_MASK, sjw) |
1126 FIELD_PREP(NBTP_NTSEG1_MASK, tseg1) |
1127 FIELD_PREP(NBTP_NTSEG2_MASK, tseg2);
1128 m_can_write(cdev, M_CAN_NBTP, reg_btp);
1130 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1134 tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
1135 tseg2 = dbt->phase_seg2 - 1;
1137 /* TDC is only needed for bitrates beyond 2.5 MBit/s.
1138 * This is mentioned in the "Bit Time Requirements for CAN FD"
1139 * paper presented at the International CAN Conference 2013
1141 if (dbt->bitrate > 2500000) {
1144 /* Use the same value of secondary sampling point
1145 * as the data sampling point
1147 ssp = dbt->sample_point;
1149 /* Equation based on Bosch's M_CAN User Manual's
1150 * Transmitter Delay Compensation Section
1152 tdco = (cdev->can.clock.freq / 1000) *
1155 /* Max valid TDCO value is 127 */
1157 netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n",
1162 reg_btp |= DBTP_TDC;
1163 m_can_write(cdev, M_CAN_TDCR,
1164 FIELD_PREP(TDCR_TDCO_MASK, tdco));
1167 reg_btp |= FIELD_PREP(DBTP_DBRP_MASK, brp) |
1168 FIELD_PREP(DBTP_DSJW_MASK, sjw) |
1169 FIELD_PREP(DBTP_DTSEG1_MASK, tseg1) |
1170 FIELD_PREP(DBTP_DTSEG2_MASK, tseg2);
1172 m_can_write(cdev, M_CAN_DBTP, reg_btp);
1178 /* Configure M_CAN chip:
1179 * - set rx buffer/fifo element size
1180 * - configure rx fifo
1181 * - accept non-matching frame into fifo 0
1182 * - configure tx buffer
1183 * - >= v3.1.x: TX FIFO is used
1186 * - configure timestamp generation
1188 static void m_can_chip_config(struct net_device *dev)
1190 struct m_can_classdev *cdev = netdev_priv(dev);
1193 m_can_config_endisable(cdev, true);
1195 /* RX Buffer/FIFO Element Size 64 bytes data field */
1196 m_can_write(cdev, M_CAN_RXESC,
1197 FIELD_PREP(RXESC_RBDS_MASK, RXESC_64B) |
1198 FIELD_PREP(RXESC_F1DS_MASK, RXESC_64B) |
1199 FIELD_PREP(RXESC_F0DS_MASK, RXESC_64B));
1201 /* Accept Non-matching Frames Into FIFO 0 */
1202 m_can_write(cdev, M_CAN_GFC, 0x0);
1204 if (cdev->version == 30) {
1205 /* only support one Tx Buffer currently */
1206 m_can_write(cdev, M_CAN_TXBC, FIELD_PREP(TXBC_NDTB_MASK, 1) |
1207 cdev->mcfg[MRAM_TXB].off);
1209 /* TX FIFO is used for newer IP Core versions */
1210 m_can_write(cdev, M_CAN_TXBC,
1211 FIELD_PREP(TXBC_TFQS_MASK,
1212 cdev->mcfg[MRAM_TXB].num) |
1213 cdev->mcfg[MRAM_TXB].off);
1216 /* support 64 bytes payload */
1217 m_can_write(cdev, M_CAN_TXESC,
1218 FIELD_PREP(TXESC_TBDS_MASK, TXESC_TBDS_64B));
1221 if (cdev->version == 30) {
1222 m_can_write(cdev, M_CAN_TXEFC,
1223 FIELD_PREP(TXEFC_EFS_MASK, 1) |
1224 cdev->mcfg[MRAM_TXE].off);
1226 /* Full TX Event FIFO is used */
1227 m_can_write(cdev, M_CAN_TXEFC,
1228 FIELD_PREP(TXEFC_EFS_MASK,
1229 cdev->mcfg[MRAM_TXE].num) |
1230 cdev->mcfg[MRAM_TXE].off);
1233 /* rx fifo configuration, blocking mode, fifo size 1 */
1234 m_can_write(cdev, M_CAN_RXF0C,
1235 FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF0].num) |
1236 cdev->mcfg[MRAM_RXF0].off);
1238 m_can_write(cdev, M_CAN_RXF1C,
1239 FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF1].num) |
1240 cdev->mcfg[MRAM_RXF1].off);
1242 cccr = m_can_read(cdev, M_CAN_CCCR);
1243 test = m_can_read(cdev, M_CAN_TEST);
1245 if (cdev->version == 30) {
1248 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_DAR |
1249 FIELD_PREP(CCCR_CMR_MASK, FIELD_MAX(CCCR_CMR_MASK)) |
1250 FIELD_PREP(CCCR_CME_MASK, FIELD_MAX(CCCR_CME_MASK)));
1252 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1253 cccr |= FIELD_PREP(CCCR_CME_MASK, CCCR_CME_CANFD_BRS);
1256 /* Version 3.1.x or 3.2.x */
1257 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE |
1258 CCCR_NISO | CCCR_DAR);
1260 /* Only 3.2.x has NISO Bit implemented */
1261 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
1264 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1265 cccr |= (CCCR_BRSE | CCCR_FDOE);
1269 if (cdev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1270 cccr |= CCCR_TEST | CCCR_MON;
1274 /* Enable Monitoring (all versions) */
1275 if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1278 /* Disable Auto Retransmission (all versions) */
1279 if (cdev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
1283 m_can_write(cdev, M_CAN_CCCR, cccr);
1284 m_can_write(cdev, M_CAN_TEST, test);
1286 /* Enable interrupts */
1287 m_can_write(cdev, M_CAN_IR, IR_ALL_INT);
1288 if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1289 if (cdev->version == 30)
1290 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1293 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1296 m_can_write(cdev, M_CAN_IE, IR_ALL_INT);
1298 /* route all interrupts to INT0 */
1299 m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0);
1301 /* set bittiming params */
1302 m_can_set_bittiming(dev);
1304 /* enable internal timestamp generation, with a prescalar of 16. The
1305 * prescalar is applied to the nominal bit timing */
1306 m_can_write(cdev, M_CAN_TSCC, FIELD_PREP(TSCC_TCP_MASK, 0xf));
1308 m_can_config_endisable(cdev, false);
1310 if (cdev->ops->init)
1311 cdev->ops->init(cdev);
1314 static void m_can_start(struct net_device *dev)
1316 struct m_can_classdev *cdev = netdev_priv(dev);
1318 /* basic m_can configuration */
1319 m_can_chip_config(dev);
1321 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
1323 m_can_enable_all_interrupts(cdev);
1326 static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
1329 case CAN_MODE_START:
1332 netif_wake_queue(dev);
1341 /* Checks core release number of M_CAN
1342 * returns 0 if an unsupported device is detected
1343 * else it returns the release and step coded as:
1344 * return value = 10 * <release> + 1 * <step>
1346 static int m_can_check_core_release(struct m_can_classdev *cdev)
1353 /* Read Core Release Version and split into version number
1354 * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1;
1356 crel_reg = m_can_read(cdev, M_CAN_CREL);
1357 rel = (u8)FIELD_GET(CREL_REL_MASK, crel_reg);
1358 step = (u8)FIELD_GET(CREL_STEP_MASK, crel_reg);
1361 /* M_CAN v3.x.y: create return value */
1364 /* Unsupported M_CAN version */
1371 /* Selectable Non ISO support only in version 3.2.x
1372 * This function checks if the bit is writable.
1374 static bool m_can_niso_supported(struct m_can_classdev *cdev)
1376 u32 cccr_reg, cccr_poll = 0;
1377 int niso_timeout = -ETIMEDOUT;
1380 m_can_config_endisable(cdev, true);
1381 cccr_reg = m_can_read(cdev, M_CAN_CCCR);
1382 cccr_reg |= CCCR_NISO;
1383 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1385 for (i = 0; i <= 10; i++) {
1386 cccr_poll = m_can_read(cdev, M_CAN_CCCR);
1387 if (cccr_poll == cccr_reg) {
1396 cccr_reg &= ~(CCCR_NISO);
1397 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1399 m_can_config_endisable(cdev, false);
1401 /* return false if time out (-ETIMEDOUT), else return true */
1402 return !niso_timeout;
1405 static int m_can_dev_setup(struct m_can_classdev *cdev)
1407 struct net_device *dev = cdev->net;
1410 m_can_version = m_can_check_core_release(cdev);
1411 /* return if unsupported version */
1412 if (!m_can_version) {
1413 dev_err(cdev->dev, "Unsupported version number: %2d",
1418 if (!cdev->is_peripheral)
1419 netif_napi_add(dev, &cdev->napi,
1420 m_can_poll, M_CAN_NAPI_WEIGHT);
1422 /* Shared properties of all M_CAN versions */
1423 cdev->version = m_can_version;
1424 cdev->can.do_set_mode = m_can_set_mode;
1425 cdev->can.do_get_berr_counter = m_can_get_berr_counter;
1427 /* Set M_CAN supported operations */
1428 cdev->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1429 CAN_CTRLMODE_LISTENONLY |
1430 CAN_CTRLMODE_BERR_REPORTING |
1432 CAN_CTRLMODE_ONE_SHOT;
1434 /* Set properties depending on M_CAN version */
1435 switch (cdev->version) {
1437 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */
1438 can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1439 cdev->can.bittiming_const = cdev->bit_timing ?
1440 cdev->bit_timing : &m_can_bittiming_const_30X;
1442 cdev->can.data_bittiming_const = cdev->data_timing ?
1444 &m_can_data_bittiming_const_30X;
1447 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */
1448 can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1449 cdev->can.bittiming_const = cdev->bit_timing ?
1450 cdev->bit_timing : &m_can_bittiming_const_31X;
1452 cdev->can.data_bittiming_const = cdev->data_timing ?
1454 &m_can_data_bittiming_const_31X;
1458 /* Support both MCAN version v3.2.x and v3.3.0 */
1459 cdev->can.bittiming_const = cdev->bit_timing ?
1460 cdev->bit_timing : &m_can_bittiming_const_31X;
1462 cdev->can.data_bittiming_const = cdev->data_timing ?
1464 &m_can_data_bittiming_const_31X;
1466 cdev->can.ctrlmode_supported |=
1467 (m_can_niso_supported(cdev) ?
1468 CAN_CTRLMODE_FD_NON_ISO : 0);
1471 dev_err(cdev->dev, "Unsupported version number: %2d",
1476 if (cdev->ops->init)
1477 cdev->ops->init(cdev);
1482 static void m_can_stop(struct net_device *dev)
1484 struct m_can_classdev *cdev = netdev_priv(dev);
1486 /* disable all interrupts */
1487 m_can_disable_all_interrupts(cdev);
1489 /* Set init mode to disengage from the network */
1490 m_can_config_endisable(cdev, true);
1492 /* set the state as STOPPED */
1493 cdev->can.state = CAN_STATE_STOPPED;
1496 static int m_can_close(struct net_device *dev)
1498 struct m_can_classdev *cdev = netdev_priv(dev);
1500 netif_stop_queue(dev);
1502 if (!cdev->is_peripheral)
1503 napi_disable(&cdev->napi);
1506 m_can_clk_stop(cdev);
1507 free_irq(dev->irq, dev);
1509 if (cdev->is_peripheral) {
1510 cdev->tx_skb = NULL;
1511 destroy_workqueue(cdev->tx_wq);
1515 if (cdev->is_peripheral)
1516 can_rx_offload_disable(&cdev->offload);
1519 can_led_event(dev, CAN_LED_EVENT_STOP);
1524 static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx)
1526 struct m_can_classdev *cdev = netdev_priv(dev);
1527 /*get wrap around for loopback skb index */
1528 unsigned int wrap = cdev->can.echo_skb_max;
1531 /* calculate next index */
1532 next_idx = (++putidx >= wrap ? 0 : putidx);
1534 /* check if occupied */
1535 return !!cdev->can.echo_skb[next_idx];
1538 static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
1540 struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data;
1541 struct net_device *dev = cdev->net;
1542 struct sk_buff *skb = cdev->tx_skb;
1543 u32 id, cccr, fdflags;
1547 cdev->tx_skb = NULL;
1549 /* Generate ID field for TX buffer Element */
1550 /* Common to all supported M_CAN versions */
1551 if (cf->can_id & CAN_EFF_FLAG) {
1552 id = cf->can_id & CAN_EFF_MASK;
1555 id = ((cf->can_id & CAN_SFF_MASK) << 18);
1558 if (cf->can_id & CAN_RTR_FLAG)
1561 if (cdev->version == 30) {
1562 netif_stop_queue(dev);
1564 /* message ram configuration */
1565 m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, id);
1566 m_can_fifo_write(cdev, 0, M_CAN_FIFO_DLC,
1567 can_fd_len2dlc(cf->len) << 16);
1569 for (i = 0; i < cf->len; i += 4)
1570 m_can_fifo_write(cdev, 0,
1571 M_CAN_FIFO_DATA(i / 4),
1572 *(u32 *)(cf->data + i));
1574 can_put_echo_skb(skb, dev, 0, 0);
1576 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1577 cccr = m_can_read(cdev, M_CAN_CCCR);
1578 cccr &= ~CCCR_CMR_MASK;
1579 if (can_is_canfd_skb(skb)) {
1580 if (cf->flags & CANFD_BRS)
1581 cccr |= FIELD_PREP(CCCR_CMR_MASK,
1582 CCCR_CMR_CANFD_BRS);
1584 cccr |= FIELD_PREP(CCCR_CMR_MASK,
1587 cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CAN);
1589 m_can_write(cdev, M_CAN_CCCR, cccr);
1591 m_can_write(cdev, M_CAN_TXBTIE, 0x1);
1592 m_can_write(cdev, M_CAN_TXBAR, 0x1);
1593 /* End of xmit function for version 3.0.x */
1595 /* Transmit routine for version >= v3.1.x */
1597 /* Check if FIFO full */
1598 if (m_can_tx_fifo_full(cdev)) {
1599 /* This shouldn't happen */
1600 netif_stop_queue(dev);
1602 "TX queue active although FIFO is full.");
1604 if (cdev->is_peripheral) {
1606 dev->stats.tx_dropped++;
1607 return NETDEV_TX_OK;
1609 return NETDEV_TX_BUSY;
1613 /* get put index for frame */
1614 putidx = FIELD_GET(TXFQS_TFQPI_MASK,
1615 m_can_read(cdev, M_CAN_TXFQS));
1616 /* Write ID Field to FIFO Element */
1617 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, id);
1619 /* get CAN FD configuration of frame */
1621 if (can_is_canfd_skb(skb)) {
1622 fdflags |= TX_BUF_FDF;
1623 if (cf->flags & CANFD_BRS)
1624 fdflags |= TX_BUF_BRS;
1627 /* Construct DLC Field. Also contains CAN-FD configuration
1628 * use put index of fifo as message marker
1629 * it is used in TX interrupt for
1630 * sending the correct echo frame
1632 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DLC,
1633 FIELD_PREP(TX_BUF_MM_MASK, putidx) |
1634 FIELD_PREP(TX_BUF_DLC_MASK,
1635 can_fd_len2dlc(cf->len)) |
1636 fdflags | TX_BUF_EFC);
1638 for (i = 0; i < cf->len; i += 4)
1639 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA(i / 4),
1640 *(u32 *)(cf->data + i));
1642 /* Push loopback echo.
1643 * Will be looped back on TX interrupt based on message marker
1645 can_put_echo_skb(skb, dev, putidx, 0);
1647 /* Enable TX FIFO element to start transfer */
1648 m_can_write(cdev, M_CAN_TXBAR, (1 << putidx));
1650 /* stop network queue if fifo full */
1651 if (m_can_tx_fifo_full(cdev) ||
1652 m_can_next_echo_skb_occupied(dev, putidx))
1653 netif_stop_queue(dev);
1656 return NETDEV_TX_OK;
1659 static void m_can_tx_work_queue(struct work_struct *ws)
1661 struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev,
1664 m_can_tx_handler(cdev);
1667 static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
1668 struct net_device *dev)
1670 struct m_can_classdev *cdev = netdev_priv(dev);
1672 if (can_dropped_invalid_skb(dev, skb))
1673 return NETDEV_TX_OK;
1675 if (cdev->is_peripheral) {
1677 netdev_err(dev, "hard_xmit called while tx busy\n");
1678 return NETDEV_TX_BUSY;
1681 if (cdev->can.state == CAN_STATE_BUS_OFF) {
1684 /* Need to stop the queue to avoid numerous requests
1685 * from being sent. Suggested improvement is to create
1686 * a queueing mechanism that will queue the skbs and
1687 * process them in order.
1690 netif_stop_queue(cdev->net);
1691 queue_work(cdev->tx_wq, &cdev->tx_work);
1695 return m_can_tx_handler(cdev);
1698 return NETDEV_TX_OK;
1701 static int m_can_open(struct net_device *dev)
1703 struct m_can_classdev *cdev = netdev_priv(dev);
1706 err = m_can_clk_start(cdev);
1710 /* open the can device */
1711 err = open_candev(dev);
1713 netdev_err(dev, "failed to open can device\n");
1714 goto exit_disable_clks;
1717 if (cdev->is_peripheral)
1718 can_rx_offload_enable(&cdev->offload);
1720 /* register interrupt handler */
1721 if (cdev->is_peripheral) {
1722 cdev->tx_skb = NULL;
1723 cdev->tx_wq = alloc_workqueue("mcan_wq",
1724 WQ_FREEZABLE | WQ_MEM_RECLAIM, 0);
1730 INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);
1732 err = request_threaded_irq(dev->irq, NULL, m_can_isr,
1736 err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
1741 netdev_err(dev, "failed to request interrupt\n");
1745 /* start the m_can controller */
1748 can_led_event(dev, CAN_LED_EVENT_OPEN);
1750 if (!cdev->is_peripheral)
1751 napi_enable(&cdev->napi);
1753 netif_start_queue(dev);
1758 if (cdev->is_peripheral)
1759 destroy_workqueue(cdev->tx_wq);
1761 if (cdev->is_peripheral)
1762 can_rx_offload_disable(&cdev->offload);
1765 m_can_clk_stop(cdev);
1769 static const struct net_device_ops m_can_netdev_ops = {
1770 .ndo_open = m_can_open,
1771 .ndo_stop = m_can_close,
1772 .ndo_start_xmit = m_can_start_xmit,
1773 .ndo_change_mtu = can_change_mtu,
1776 static int register_m_can_dev(struct net_device *dev)
1778 dev->flags |= IFF_ECHO; /* we support local echo */
1779 dev->netdev_ops = &m_can_netdev_ops;
1781 return register_candev(dev);
1784 static void m_can_of_parse_mram(struct m_can_classdev *cdev,
1785 const u32 *mram_config_vals)
1787 cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0];
1788 cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1];
1789 cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off +
1790 cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
1791 cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2];
1792 cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off +
1793 cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
1794 cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] &
1795 FIELD_MAX(RXFC_FS_MASK);
1796 cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off +
1797 cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
1798 cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] &
1799 FIELD_MAX(RXFC_FS_MASK);
1800 cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off +
1801 cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
1802 cdev->mcfg[MRAM_RXB].num = mram_config_vals[5];
1803 cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off +
1804 cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
1805 cdev->mcfg[MRAM_TXE].num = mram_config_vals[6];
1806 cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off +
1807 cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
1808 cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] &
1809 FIELD_MAX(TXBC_NDTB_MASK);
1812 "sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n",
1813 cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num,
1814 cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num,
1815 cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num,
1816 cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num,
1817 cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num,
1818 cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num,
1819 cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num);
1822 void m_can_init_ram(struct m_can_classdev *cdev)
1826 /* initialize the entire Message RAM in use to avoid possible
1827 * ECC/parity checksum errors when reading an uninitialized buffer
1829 start = cdev->mcfg[MRAM_SIDF].off;
1830 end = cdev->mcfg[MRAM_TXB].off +
1831 cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;
1833 for (i = start; i < end; i += 4)
1834 m_can_fifo_write_no_off(cdev, i, 0x0);
1836 EXPORT_SYMBOL_GPL(m_can_init_ram);
1838 int m_can_class_get_clocks(struct m_can_classdev *cdev)
1842 cdev->hclk = devm_clk_get(cdev->dev, "hclk");
1843 cdev->cclk = devm_clk_get(cdev->dev, "cclk");
1845 if (IS_ERR(cdev->cclk)) {
1846 dev_err(cdev->dev, "no clock found\n");
1852 EXPORT_SYMBOL_GPL(m_can_class_get_clocks);
1854 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
1857 struct m_can_classdev *class_dev = NULL;
1858 u32 mram_config_vals[MRAM_CFG_LEN];
1859 struct net_device *net_dev;
1863 ret = fwnode_property_read_u32_array(dev_fwnode(dev),
1866 sizeof(mram_config_vals) / 4);
1868 dev_err(dev, "Could not get Message RAM configuration.");
1873 * Defines the total amount of echo buffers for loopback
1875 tx_fifo_size = mram_config_vals[7];
1877 /* allocate the m_can device */
1878 net_dev = alloc_candev(sizeof_priv, tx_fifo_size);
1880 dev_err(dev, "Failed to allocate CAN device");
1884 class_dev = netdev_priv(net_dev);
1885 class_dev->net = net_dev;
1886 class_dev->dev = dev;
1887 SET_NETDEV_DEV(net_dev, dev);
1889 m_can_of_parse_mram(class_dev, mram_config_vals);
1893 EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);
1895 void m_can_class_free_dev(struct net_device *net)
1899 EXPORT_SYMBOL_GPL(m_can_class_free_dev);
1901 int m_can_class_register(struct m_can_classdev *cdev)
1905 if (cdev->pm_clock_support) {
1906 ret = m_can_clk_start(cdev);
1911 if (cdev->is_peripheral) {
1912 ret = can_rx_offload_add_manual(cdev->net, &cdev->offload,
1918 ret = m_can_dev_setup(cdev);
1920 goto rx_offload_del;
1922 ret = register_m_can_dev(cdev->net);
1924 dev_err(cdev->dev, "registering %s failed (err=%d)\n",
1925 cdev->net->name, ret);
1926 goto rx_offload_del;
1929 devm_can_led_init(cdev->net);
1931 of_can_transceiver(cdev->net);
1933 dev_info(cdev->dev, "%s device registered (irq=%d, version=%d)\n",
1934 KBUILD_MODNAME, cdev->net->irq, cdev->version);
1937 * Stop clocks. They will be reactivated once the M_CAN device is opened
1939 m_can_clk_stop(cdev);
1944 if (cdev->is_peripheral)
1945 can_rx_offload_del(&cdev->offload);
1947 m_can_clk_stop(cdev);
1951 EXPORT_SYMBOL_GPL(m_can_class_register);
1953 void m_can_class_unregister(struct m_can_classdev *cdev)
1955 if (cdev->is_peripheral)
1956 can_rx_offload_del(&cdev->offload);
1957 unregister_candev(cdev->net);
1959 EXPORT_SYMBOL_GPL(m_can_class_unregister);
1961 int m_can_class_suspend(struct device *dev)
1963 struct m_can_classdev *cdev = dev_get_drvdata(dev);
1964 struct net_device *ndev = cdev->net;
1966 if (netif_running(ndev)) {
1967 netif_stop_queue(ndev);
1968 netif_device_detach(ndev);
1970 m_can_clk_stop(cdev);
1973 pinctrl_pm_select_sleep_state(dev);
1975 cdev->can.state = CAN_STATE_SLEEPING;
1979 EXPORT_SYMBOL_GPL(m_can_class_suspend);
1981 int m_can_class_resume(struct device *dev)
1983 struct m_can_classdev *cdev = dev_get_drvdata(dev);
1984 struct net_device *ndev = cdev->net;
1986 pinctrl_pm_select_default_state(dev);
1988 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
1990 if (netif_running(ndev)) {
1993 ret = m_can_clk_start(cdev);
1997 m_can_init_ram(cdev);
1999 netif_device_attach(ndev);
2000 netif_start_queue(ndev);
2005 EXPORT_SYMBOL_GPL(m_can_class_resume);
2007 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
2008 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
2009 MODULE_LICENSE("GPL v2");
2010 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");