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 * http://www.bosch-semiconductors.de/media/pdf_1/ipmodules_1/m_can/
9 * mcan_users_manual_v302.pdf
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_SHIFT 28
87 #define CREL_REL_MASK (0xF << CREL_REL_SHIFT)
88 #define CREL_STEP_SHIFT 24
89 #define CREL_STEP_MASK (0xF << CREL_STEP_SHIFT)
90 #define CREL_SUBSTEP_SHIFT 20
91 #define CREL_SUBSTEP_MASK (0xF << CREL_SUBSTEP_SHIFT)
93 /* Data Bit Timing & Prescaler Register (DBTP) */
94 #define DBTP_TDC BIT(23)
95 #define DBTP_DBRP_SHIFT 16
96 #define DBTP_DBRP_MASK (0x1f << DBTP_DBRP_SHIFT)
97 #define DBTP_DTSEG1_SHIFT 8
98 #define DBTP_DTSEG1_MASK (0x1f << DBTP_DTSEG1_SHIFT)
99 #define DBTP_DTSEG2_SHIFT 4
100 #define DBTP_DTSEG2_MASK (0xf << DBTP_DTSEG2_SHIFT)
101 #define DBTP_DSJW_SHIFT 0
102 #define DBTP_DSJW_MASK (0xf << DBTP_DSJW_SHIFT)
104 /* Transmitter Delay Compensation Register (TDCR) */
105 #define TDCR_TDCO_SHIFT 8
106 #define TDCR_TDCO_MASK (0x7F << TDCR_TDCO_SHIFT)
107 #define TDCR_TDCF_SHIFT 0
108 #define TDCR_TDCF_MASK (0x7F << TDCR_TDCF_SHIFT)
110 /* Test Register (TEST) */
111 #define TEST_LBCK BIT(4)
113 /* CC Control Register(CCCR) */
114 #define CCCR_CMR_MASK 0x3
115 #define CCCR_CMR_SHIFT 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 0x3
120 #define CCCR_CME_SHIFT 8
121 #define CCCR_CME_CAN 0
122 #define CCCR_CME_CANFD 0x1
123 #define CCCR_CME_CANFD_BRS 0x2
124 #define CCCR_TXP BIT(14)
125 #define CCCR_TEST BIT(7)
126 #define CCCR_DAR BIT(6)
127 #define CCCR_MON BIT(5)
128 #define CCCR_CSR BIT(4)
129 #define CCCR_CSA BIT(3)
130 #define CCCR_ASM BIT(2)
131 #define CCCR_CCE BIT(1)
132 #define CCCR_INIT BIT(0)
133 #define CCCR_CANFD 0x10
134 /* for version >=3.1.x */
135 #define CCCR_EFBI BIT(13)
136 #define CCCR_PXHD BIT(12)
137 #define CCCR_BRSE BIT(9)
138 #define CCCR_FDOE BIT(8)
139 /* only for version >=3.2.x */
140 #define CCCR_NISO BIT(15)
142 /* Nominal Bit Timing & Prescaler Register (NBTP) */
143 #define NBTP_NSJW_SHIFT 25
144 #define NBTP_NSJW_MASK (0x7f << NBTP_NSJW_SHIFT)
145 #define NBTP_NBRP_SHIFT 16
146 #define NBTP_NBRP_MASK (0x1ff << NBTP_NBRP_SHIFT)
147 #define NBTP_NTSEG1_SHIFT 8
148 #define NBTP_NTSEG1_MASK (0xff << NBTP_NTSEG1_SHIFT)
149 #define NBTP_NTSEG2_SHIFT 0
150 #define NBTP_NTSEG2_MASK (0x7f << NBTP_NTSEG2_SHIFT)
152 /* Error Counter Register(ECR) */
153 #define ECR_RP BIT(15)
154 #define ECR_REC_SHIFT 8
155 #define ECR_REC_MASK (0x7f << ECR_REC_SHIFT)
156 #define ECR_TEC_SHIFT 0
157 #define ECR_TEC_MASK 0xff
159 /* Protocol Status Register(PSR) */
160 #define PSR_BO BIT(7)
161 #define PSR_EW BIT(6)
162 #define PSR_EP BIT(5)
163 #define PSR_LEC_MASK 0x7
165 /* Interrupt Register(IR) */
166 #define IR_ALL_INT 0xffffffff
168 /* Renamed bits for versions > 3.1.x */
169 #define IR_ARA BIT(29)
170 #define IR_PED BIT(28)
171 #define IR_PEA BIT(27)
173 /* Bits for version 3.0.x */
174 #define IR_STE BIT(31)
175 #define IR_FOE BIT(30)
176 #define IR_ACKE BIT(29)
177 #define IR_BE BIT(28)
178 #define IR_CRCE BIT(27)
179 #define IR_WDI BIT(26)
180 #define IR_BO BIT(25)
181 #define IR_EW BIT(24)
182 #define IR_EP BIT(23)
183 #define IR_ELO BIT(22)
184 #define IR_BEU BIT(21)
185 #define IR_BEC BIT(20)
186 #define IR_DRX BIT(19)
187 #define IR_TOO BIT(18)
188 #define IR_MRAF BIT(17)
189 #define IR_TSW BIT(16)
190 #define IR_TEFL BIT(15)
191 #define IR_TEFF BIT(14)
192 #define IR_TEFW BIT(13)
193 #define IR_TEFN BIT(12)
194 #define IR_TFE BIT(11)
195 #define IR_TCF BIT(10)
197 #define IR_HPM BIT(8)
198 #define IR_RF1L BIT(7)
199 #define IR_RF1F BIT(6)
200 #define IR_RF1W BIT(5)
201 #define IR_RF1N BIT(4)
202 #define IR_RF0L BIT(3)
203 #define IR_RF0F BIT(2)
204 #define IR_RF0W BIT(1)
205 #define IR_RF0N BIT(0)
206 #define IR_ERR_STATE (IR_BO | IR_EW | IR_EP)
208 /* Interrupts for version 3.0.x */
209 #define IR_ERR_LEC_30X (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
210 #define IR_ERR_BUS_30X (IR_ERR_LEC_30X | IR_WDI | IR_BEU | IR_BEC | \
211 IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \
213 #define IR_ERR_ALL_30X (IR_ERR_STATE | IR_ERR_BUS_30X)
214 /* Interrupts for version >= 3.1.x */
215 #define IR_ERR_LEC_31X (IR_PED | IR_PEA)
216 #define IR_ERR_BUS_31X (IR_ERR_LEC_31X | IR_WDI | IR_BEU | IR_BEC | \
217 IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \
219 #define IR_ERR_ALL_31X (IR_ERR_STATE | IR_ERR_BUS_31X)
221 /* Interrupt Line Select (ILS) */
222 #define ILS_ALL_INT0 0x0
223 #define ILS_ALL_INT1 0xFFFFFFFF
225 /* Interrupt Line Enable (ILE) */
226 #define ILE_EINT1 BIT(1)
227 #define ILE_EINT0 BIT(0)
229 /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
230 #define RXFC_FWM_SHIFT 24
231 #define RXFC_FWM_MASK (0x7f << RXFC_FWM_SHIFT)
232 #define RXFC_FS_SHIFT 16
233 #define RXFC_FS_MASK (0x7f << RXFC_FS_SHIFT)
235 /* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
236 #define RXFS_RFL BIT(25)
237 #define RXFS_FF BIT(24)
238 #define RXFS_FPI_SHIFT 16
239 #define RXFS_FPI_MASK 0x3f0000
240 #define RXFS_FGI_SHIFT 8
241 #define RXFS_FGI_MASK 0x3f00
242 #define RXFS_FFL_MASK 0x7f
244 /* Rx Buffer / FIFO Element Size Configuration (RXESC) */
245 #define M_CAN_RXESC_8BYTES 0x0
246 #define M_CAN_RXESC_64BYTES 0x777
248 /* Tx Buffer Configuration(TXBC) */
249 #define TXBC_NDTB_SHIFT 16
250 #define TXBC_NDTB_MASK (0x3f << TXBC_NDTB_SHIFT)
251 #define TXBC_TFQS_SHIFT 24
252 #define TXBC_TFQS_MASK (0x3f << TXBC_TFQS_SHIFT)
254 /* Tx FIFO/Queue Status (TXFQS) */
255 #define TXFQS_TFQF BIT(21)
256 #define TXFQS_TFQPI_SHIFT 16
257 #define TXFQS_TFQPI_MASK (0x1f << TXFQS_TFQPI_SHIFT)
258 #define TXFQS_TFGI_SHIFT 8
259 #define TXFQS_TFGI_MASK (0x1f << TXFQS_TFGI_SHIFT)
260 #define TXFQS_TFFL_SHIFT 0
261 #define TXFQS_TFFL_MASK (0x3f << TXFQS_TFFL_SHIFT)
263 /* Tx Buffer Element Size Configuration(TXESC) */
264 #define TXESC_TBDS_8BYTES 0x0
265 #define TXESC_TBDS_64BYTES 0x7
267 /* Tx Event FIFO Configuration (TXEFC) */
268 #define TXEFC_EFS_SHIFT 16
269 #define TXEFC_EFS_MASK (0x3f << TXEFC_EFS_SHIFT)
271 /* Tx Event FIFO Status (TXEFS) */
272 #define TXEFS_TEFL BIT(25)
273 #define TXEFS_EFF BIT(24)
274 #define TXEFS_EFGI_SHIFT 8
275 #define TXEFS_EFGI_MASK (0x1f << TXEFS_EFGI_SHIFT)
276 #define TXEFS_EFFL_SHIFT 0
277 #define TXEFS_EFFL_MASK (0x3f << TXEFS_EFFL_SHIFT)
279 /* Tx Event FIFO Acknowledge (TXEFA) */
280 #define TXEFA_EFAI_SHIFT 0
281 #define TXEFA_EFAI_MASK (0x1f << TXEFA_EFAI_SHIFT)
283 /* Message RAM Configuration (in bytes) */
284 #define SIDF_ELEMENT_SIZE 4
285 #define XIDF_ELEMENT_SIZE 8
286 #define RXF0_ELEMENT_SIZE 72
287 #define RXF1_ELEMENT_SIZE 72
288 #define RXB_ELEMENT_SIZE 72
289 #define TXE_ELEMENT_SIZE 8
290 #define TXB_ELEMENT_SIZE 72
292 /* Message RAM Elements */
293 #define M_CAN_FIFO_ID 0x0
294 #define M_CAN_FIFO_DLC 0x4
295 #define M_CAN_FIFO_DATA(n) (0x8 + ((n) << 2))
297 /* Rx Buffer Element */
299 #define RX_BUF_ESI BIT(31)
300 #define RX_BUF_XTD BIT(30)
301 #define RX_BUF_RTR BIT(29)
303 #define RX_BUF_ANMF BIT(31)
304 #define RX_BUF_FDF BIT(21)
305 #define RX_BUF_BRS BIT(20)
307 /* Tx Buffer Element */
309 #define TX_BUF_ESI BIT(31)
310 #define TX_BUF_XTD BIT(30)
311 #define TX_BUF_RTR BIT(29)
313 #define TX_BUF_EFC BIT(23)
314 #define TX_BUF_FDF BIT(21)
315 #define TX_BUF_BRS BIT(20)
316 #define TX_BUF_MM_SHIFT 24
317 #define TX_BUF_MM_MASK (0xff << TX_BUF_MM_SHIFT)
319 /* Tx event FIFO Element */
321 #define TX_EVENT_MM_SHIFT TX_BUF_MM_SHIFT
322 #define TX_EVENT_MM_MASK (0xff << TX_EVENT_MM_SHIFT)
324 static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg)
326 return cdev->ops->read_reg(cdev, reg);
329 static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg,
332 cdev->ops->write_reg(cdev, reg, val);
335 static u32 m_can_fifo_read(struct m_can_classdev *cdev,
336 u32 fgi, unsigned int offset)
338 u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE +
341 return cdev->ops->read_fifo(cdev, addr_offset);
344 static void m_can_fifo_write(struct m_can_classdev *cdev,
345 u32 fpi, unsigned int offset, u32 val)
347 u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE +
350 cdev->ops->write_fifo(cdev, addr_offset, val);
353 static inline void m_can_fifo_write_no_off(struct m_can_classdev *cdev,
356 cdev->ops->write_fifo(cdev, fpi, val);
359 static u32 m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset)
361 u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE +
364 return cdev->ops->read_fifo(cdev, addr_offset);
367 static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev)
369 return !!(m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQF);
372 void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
374 u32 cccr = m_can_read(cdev, M_CAN_CCCR);
378 /* Clear the Clock stop request if it was set */
383 /* enable m_can configuration */
384 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT);
386 /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
387 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
389 m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
392 /* there's a delay for module initialization */
394 val = CCCR_INIT | CCCR_CCE;
396 while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
398 netdev_warn(cdev->net, "Failed to init module\n");
406 static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev)
408 /* Only interrupt line 0 is used in this driver */
409 m_can_write(cdev, M_CAN_ILE, ILE_EINT0);
412 static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev)
414 m_can_write(cdev, M_CAN_ILE, 0x0);
417 static void m_can_clean(struct net_device *net)
419 struct m_can_classdev *cdev = netdev_priv(net);
424 net->stats.tx_errors++;
425 if (cdev->version > 30)
426 putidx = ((m_can_read(cdev, M_CAN_TXFQS) &
427 TXFQS_TFQPI_MASK) >> TXFQS_TFQPI_SHIFT);
429 can_free_echo_skb(cdev->net, putidx);
434 static void m_can_read_fifo(struct net_device *dev, u32 rxfs)
436 struct net_device_stats *stats = &dev->stats;
437 struct m_can_classdev *cdev = netdev_priv(dev);
438 struct canfd_frame *cf;
443 /* calculate the fifo get index for where to read data */
444 fgi = (rxfs & RXFS_FGI_MASK) >> RXFS_FGI_SHIFT;
445 dlc = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DLC);
446 if (dlc & RX_BUF_FDF)
447 skb = alloc_canfd_skb(dev, &cf);
449 skb = alloc_can_skb(dev, (struct can_frame **)&cf);
455 if (dlc & RX_BUF_FDF)
456 cf->len = can_dlc2len((dlc >> 16) & 0x0F);
458 cf->len = get_can_dlc((dlc >> 16) & 0x0F);
460 id = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID);
462 cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
464 cf->can_id = (id >> 18) & CAN_SFF_MASK;
466 if (id & RX_BUF_ESI) {
467 cf->flags |= CANFD_ESI;
468 netdev_dbg(dev, "ESI Error\n");
471 if (!(dlc & RX_BUF_FDF) && (id & RX_BUF_RTR)) {
472 cf->can_id |= CAN_RTR_FLAG;
474 if (dlc & RX_BUF_BRS)
475 cf->flags |= CANFD_BRS;
477 for (i = 0; i < cf->len; i += 4)
478 *(u32 *)(cf->data + i) =
479 m_can_fifo_read(cdev, fgi,
480 M_CAN_FIFO_DATA(i / 4));
483 /* acknowledge rx fifo 0 */
484 m_can_write(cdev, M_CAN_RXF0A, fgi);
487 stats->rx_bytes += cf->len;
489 netif_receive_skb(skb);
492 static int m_can_do_rx_poll(struct net_device *dev, int quota)
494 struct m_can_classdev *cdev = netdev_priv(dev);
498 rxfs = m_can_read(cdev, M_CAN_RXF0S);
499 if (!(rxfs & RXFS_FFL_MASK)) {
500 netdev_dbg(dev, "no messages in fifo0\n");
504 while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
505 m_can_read_fifo(dev, rxfs);
509 rxfs = m_can_read(cdev, M_CAN_RXF0S);
513 can_led_event(dev, CAN_LED_EVENT_RX);
518 static int m_can_handle_lost_msg(struct net_device *dev)
520 struct net_device_stats *stats = &dev->stats;
522 struct can_frame *frame;
524 netdev_err(dev, "msg lost in rxf0\n");
527 stats->rx_over_errors++;
529 skb = alloc_can_err_skb(dev, &frame);
533 frame->can_id |= CAN_ERR_CRTL;
534 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
536 netif_receive_skb(skb);
541 static int m_can_handle_lec_err(struct net_device *dev,
542 enum m_can_lec_type lec_type)
544 struct m_can_classdev *cdev = netdev_priv(dev);
545 struct net_device_stats *stats = &dev->stats;
546 struct can_frame *cf;
549 cdev->can.can_stats.bus_error++;
552 /* propagate the error condition to the CAN stack */
553 skb = alloc_can_err_skb(dev, &cf);
557 /* check for 'last error code' which tells us the
558 * type of the last error to occur on the CAN bus
560 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
563 case LEC_STUFF_ERROR:
564 netdev_dbg(dev, "stuff error\n");
565 cf->data[2] |= CAN_ERR_PROT_STUFF;
568 netdev_dbg(dev, "form error\n");
569 cf->data[2] |= CAN_ERR_PROT_FORM;
572 netdev_dbg(dev, "ack error\n");
573 cf->data[3] = CAN_ERR_PROT_LOC_ACK;
576 netdev_dbg(dev, "bit1 error\n");
577 cf->data[2] |= CAN_ERR_PROT_BIT1;
580 netdev_dbg(dev, "bit0 error\n");
581 cf->data[2] |= CAN_ERR_PROT_BIT0;
584 netdev_dbg(dev, "CRC error\n");
585 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
592 stats->rx_bytes += cf->can_dlc;
593 netif_receive_skb(skb);
598 static int __m_can_get_berr_counter(const struct net_device *dev,
599 struct can_berr_counter *bec)
601 struct m_can_classdev *cdev = netdev_priv(dev);
604 ecr = m_can_read(cdev, M_CAN_ECR);
605 bec->rxerr = (ecr & ECR_REC_MASK) >> ECR_REC_SHIFT;
606 bec->txerr = (ecr & ECR_TEC_MASK) >> ECR_TEC_SHIFT;
611 static int m_can_clk_start(struct m_can_classdev *cdev)
615 if (cdev->pm_clock_support == 0)
618 err = pm_runtime_get_sync(cdev->dev);
620 pm_runtime_put_noidle(cdev->dev);
627 static void m_can_clk_stop(struct m_can_classdev *cdev)
629 if (cdev->pm_clock_support)
630 pm_runtime_put_sync(cdev->dev);
633 static int m_can_get_berr_counter(const struct net_device *dev,
634 struct can_berr_counter *bec)
636 struct m_can_classdev *cdev = netdev_priv(dev);
639 err = m_can_clk_start(cdev);
643 __m_can_get_berr_counter(dev, bec);
645 m_can_clk_stop(cdev);
650 static int m_can_handle_state_change(struct net_device *dev,
651 enum can_state new_state)
653 struct m_can_classdev *cdev = netdev_priv(dev);
654 struct net_device_stats *stats = &dev->stats;
655 struct can_frame *cf;
657 struct can_berr_counter bec;
661 case CAN_STATE_ERROR_WARNING:
662 /* error warning state */
663 cdev->can.can_stats.error_warning++;
664 cdev->can.state = CAN_STATE_ERROR_WARNING;
666 case CAN_STATE_ERROR_PASSIVE:
667 /* error passive state */
668 cdev->can.can_stats.error_passive++;
669 cdev->can.state = CAN_STATE_ERROR_PASSIVE;
671 case CAN_STATE_BUS_OFF:
673 cdev->can.state = CAN_STATE_BUS_OFF;
674 m_can_disable_all_interrupts(cdev);
675 cdev->can.can_stats.bus_off++;
682 /* propagate the error condition to the CAN stack */
683 skb = alloc_can_err_skb(dev, &cf);
687 __m_can_get_berr_counter(dev, &bec);
690 case CAN_STATE_ERROR_WARNING:
691 /* error warning state */
692 cf->can_id |= CAN_ERR_CRTL;
693 cf->data[1] = (bec.txerr > bec.rxerr) ?
694 CAN_ERR_CRTL_TX_WARNING :
695 CAN_ERR_CRTL_RX_WARNING;
696 cf->data[6] = bec.txerr;
697 cf->data[7] = bec.rxerr;
699 case CAN_STATE_ERROR_PASSIVE:
700 /* error passive state */
701 cf->can_id |= CAN_ERR_CRTL;
702 ecr = m_can_read(cdev, M_CAN_ECR);
704 cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
706 cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
707 cf->data[6] = bec.txerr;
708 cf->data[7] = bec.rxerr;
710 case CAN_STATE_BUS_OFF:
712 cf->can_id |= CAN_ERR_BUSOFF;
719 stats->rx_bytes += cf->can_dlc;
720 netif_receive_skb(skb);
725 static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
727 struct m_can_classdev *cdev = netdev_priv(dev);
730 if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) {
731 netdev_dbg(dev, "entered error warning state\n");
732 work_done += m_can_handle_state_change(dev,
733 CAN_STATE_ERROR_WARNING);
736 if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) {
737 netdev_dbg(dev, "entered error passive state\n");
738 work_done += m_can_handle_state_change(dev,
739 CAN_STATE_ERROR_PASSIVE);
742 if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) {
743 netdev_dbg(dev, "entered error bus off state\n");
744 work_done += m_can_handle_state_change(dev,
751 static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
753 if (irqstatus & IR_WDI)
754 netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
755 if (irqstatus & IR_BEU)
756 netdev_err(dev, "Bit Error Uncorrected\n");
757 if (irqstatus & IR_BEC)
758 netdev_err(dev, "Bit Error Corrected\n");
759 if (irqstatus & IR_TOO)
760 netdev_err(dev, "Timeout reached\n");
761 if (irqstatus & IR_MRAF)
762 netdev_err(dev, "Message RAM access failure occurred\n");
765 static inline bool is_lec_err(u32 psr)
769 return psr && (psr != LEC_UNUSED);
772 static inline bool m_can_is_protocol_err(u32 irqstatus)
774 return irqstatus & IR_ERR_LEC_31X;
777 static int m_can_handle_protocol_error(struct net_device *dev, u32 irqstatus)
779 struct net_device_stats *stats = &dev->stats;
780 struct m_can_classdev *cdev = netdev_priv(dev);
781 struct can_frame *cf;
784 /* propagate the error condition to the CAN stack */
785 skb = alloc_can_err_skb(dev, &cf);
787 /* update tx error stats since there is protocol error */
790 /* update arbitration lost status */
791 if (cdev->version >= 31 && (irqstatus & IR_PEA)) {
792 netdev_dbg(dev, "Protocol error in Arbitration fail\n");
793 cdev->can.can_stats.arbitration_lost++;
795 cf->can_id |= CAN_ERR_LOSTARB;
796 cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC;
800 if (unlikely(!skb)) {
801 netdev_dbg(dev, "allocation of skb failed\n");
804 netif_receive_skb(skb);
809 static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
812 struct m_can_classdev *cdev = netdev_priv(dev);
815 if (irqstatus & IR_RF0L)
816 work_done += m_can_handle_lost_msg(dev);
818 /* handle lec errors on the bus */
819 if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
821 work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);
823 /* handle protocol errors in arbitration phase */
824 if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
825 m_can_is_protocol_err(irqstatus))
826 work_done += m_can_handle_protocol_error(dev, irqstatus);
828 /* other unproccessed error interrupts */
829 m_can_handle_other_err(dev, irqstatus);
834 static int m_can_rx_handler(struct net_device *dev, int quota)
836 struct m_can_classdev *cdev = netdev_priv(dev);
840 irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR);
844 /* Errata workaround for issue "Needless activation of MRAF irq"
845 * During frame reception while the MCAN is in Error Passive state
846 * and the Receive Error Counter has the value MCAN_ECR.REC = 127,
847 * it may happen that MCAN_IR.MRAF is set although there was no
848 * Message RAM access failure.
849 * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated
850 * The Message RAM Access Failure interrupt routine needs to check
851 * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127.
852 * In this case, reset MCAN_IR.MRAF. No further action is required.
854 if (cdev->version <= 31 && irqstatus & IR_MRAF &&
855 m_can_read(cdev, M_CAN_ECR) & ECR_RP) {
856 struct can_berr_counter bec;
858 __m_can_get_berr_counter(dev, &bec);
859 if (bec.rxerr == 127) {
860 m_can_write(cdev, M_CAN_IR, IR_MRAF);
861 irqstatus &= ~IR_MRAF;
865 psr = m_can_read(cdev, M_CAN_PSR);
867 if (irqstatus & IR_ERR_STATE)
868 work_done += m_can_handle_state_errors(dev, psr);
870 if (irqstatus & IR_ERR_BUS_30X)
871 work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
873 if (irqstatus & IR_RF0N)
874 work_done += m_can_do_rx_poll(dev, (quota - work_done));
879 static int m_can_rx_peripheral(struct net_device *dev)
881 struct m_can_classdev *cdev = netdev_priv(dev);
883 m_can_rx_handler(dev, M_CAN_NAPI_WEIGHT);
885 m_can_enable_all_interrupts(cdev);
890 static int m_can_poll(struct napi_struct *napi, int quota)
892 struct net_device *dev = napi->dev;
893 struct m_can_classdev *cdev = netdev_priv(dev);
896 work_done = m_can_rx_handler(dev, quota);
897 if (work_done < quota) {
898 napi_complete_done(napi, work_done);
899 m_can_enable_all_interrupts(cdev);
905 static void m_can_echo_tx_event(struct net_device *dev)
911 unsigned int msg_mark;
913 struct m_can_classdev *cdev = netdev_priv(dev);
914 struct net_device_stats *stats = &dev->stats;
916 /* read tx event fifo status */
917 m_can_txefs = m_can_read(cdev, M_CAN_TXEFS);
919 /* Get Tx Event fifo element count */
920 txe_count = (m_can_txefs & TXEFS_EFFL_MASK)
923 /* Get and process all sent elements */
924 for (i = 0; i < txe_count; i++) {
925 /* retrieve get index */
926 fgi = (m_can_read(cdev, M_CAN_TXEFS) & TXEFS_EFGI_MASK)
929 /* get message marker */
930 msg_mark = (m_can_txe_fifo_read(cdev, fgi, 4) &
931 TX_EVENT_MM_MASK) >> TX_EVENT_MM_SHIFT;
933 /* ack txe element */
934 m_can_write(cdev, M_CAN_TXEFA, (TXEFA_EFAI_MASK &
935 (fgi << TXEFA_EFAI_SHIFT)));
938 stats->tx_bytes += can_get_echo_skb(dev, msg_mark);
943 static irqreturn_t m_can_isr(int irq, void *dev_id)
945 struct net_device *dev = (struct net_device *)dev_id;
946 struct m_can_classdev *cdev = netdev_priv(dev);
947 struct net_device_stats *stats = &dev->stats;
950 if (pm_runtime_suspended(cdev->dev))
952 ir = m_can_read(cdev, M_CAN_IR);
958 m_can_write(cdev, M_CAN_IR, ir);
960 if (cdev->ops->clear_interrupts)
961 cdev->ops->clear_interrupts(cdev);
963 /* schedule NAPI in case of
966 * - bus error IRQ and bus error reporting
968 if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
969 cdev->irqstatus = ir;
970 m_can_disable_all_interrupts(cdev);
971 if (!cdev->is_peripheral)
972 napi_schedule(&cdev->napi);
974 m_can_rx_peripheral(dev);
977 if (cdev->version == 30) {
979 /* Transmission Complete Interrupt*/
980 stats->tx_bytes += can_get_echo_skb(dev, 0);
982 can_led_event(dev, CAN_LED_EVENT_TX);
983 netif_wake_queue(dev);
987 /* New TX FIFO Element arrived */
988 m_can_echo_tx_event(dev);
989 can_led_event(dev, CAN_LED_EVENT_TX);
990 if (netif_queue_stopped(dev) &&
991 !m_can_tx_fifo_full(cdev))
992 netif_wake_queue(dev);
999 static const struct can_bittiming_const m_can_bittiming_const_30X = {
1000 .name = KBUILD_MODNAME,
1001 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1003 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1011 static const struct can_bittiming_const m_can_data_bittiming_const_30X = {
1012 .name = KBUILD_MODNAME,
1013 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1015 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1023 static const struct can_bittiming_const m_can_bittiming_const_31X = {
1024 .name = KBUILD_MODNAME,
1025 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1027 .tseg2_min = 2, /* Time segment 2 = phase_seg2 */
1035 static const struct can_bittiming_const m_can_data_bittiming_const_31X = {
1036 .name = KBUILD_MODNAME,
1037 .tseg1_min = 1, /* Time segment 1 = prop_seg + phase_seg1 */
1039 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1047 static int m_can_set_bittiming(struct net_device *dev)
1049 struct m_can_classdev *cdev = netdev_priv(dev);
1050 const struct can_bittiming *bt = &cdev->can.bittiming;
1051 const struct can_bittiming *dbt = &cdev->can.data_bittiming;
1052 u16 brp, sjw, tseg1, tseg2;
1057 tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
1058 tseg2 = bt->phase_seg2 - 1;
1059 reg_btp = (brp << NBTP_NBRP_SHIFT) | (sjw << NBTP_NSJW_SHIFT) |
1060 (tseg1 << NBTP_NTSEG1_SHIFT) | (tseg2 << NBTP_NTSEG2_SHIFT);
1061 m_can_write(cdev, M_CAN_NBTP, reg_btp);
1063 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1067 tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
1068 tseg2 = dbt->phase_seg2 - 1;
1070 /* TDC is only needed for bitrates beyond 2.5 MBit/s.
1071 * This is mentioned in the "Bit Time Requirements for CAN FD"
1072 * paper presented at the International CAN Conference 2013
1074 if (dbt->bitrate > 2500000) {
1077 /* Use the same value of secondary sampling point
1078 * as the data sampling point
1080 ssp = dbt->sample_point;
1082 /* Equation based on Bosch's M_CAN User Manual's
1083 * Transmitter Delay Compensation Section
1085 tdco = (cdev->can.clock.freq / 1000) *
1088 /* Max valid TDCO value is 127 */
1090 netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n",
1095 reg_btp |= DBTP_TDC;
1096 m_can_write(cdev, M_CAN_TDCR,
1097 tdco << TDCR_TDCO_SHIFT);
1100 reg_btp |= (brp << DBTP_DBRP_SHIFT) |
1101 (sjw << DBTP_DSJW_SHIFT) |
1102 (tseg1 << DBTP_DTSEG1_SHIFT) |
1103 (tseg2 << DBTP_DTSEG2_SHIFT);
1105 m_can_write(cdev, M_CAN_DBTP, reg_btp);
1111 /* Configure M_CAN chip:
1112 * - set rx buffer/fifo element size
1113 * - configure rx fifo
1114 * - accept non-matching frame into fifo 0
1115 * - configure tx buffer
1116 * - >= v3.1.x: TX FIFO is used
1120 static void m_can_chip_config(struct net_device *dev)
1122 struct m_can_classdev *cdev = netdev_priv(dev);
1125 m_can_config_endisable(cdev, true);
1127 /* RX Buffer/FIFO Element Size 64 bytes data field */
1128 m_can_write(cdev, M_CAN_RXESC, M_CAN_RXESC_64BYTES);
1130 /* Accept Non-matching Frames Into FIFO 0 */
1131 m_can_write(cdev, M_CAN_GFC, 0x0);
1133 if (cdev->version == 30) {
1134 /* only support one Tx Buffer currently */
1135 m_can_write(cdev, M_CAN_TXBC, (1 << TXBC_NDTB_SHIFT) |
1136 cdev->mcfg[MRAM_TXB].off);
1138 /* TX FIFO is used for newer IP Core versions */
1139 m_can_write(cdev, M_CAN_TXBC,
1140 (cdev->mcfg[MRAM_TXB].num << TXBC_TFQS_SHIFT) |
1141 (cdev->mcfg[MRAM_TXB].off));
1144 /* support 64 bytes payload */
1145 m_can_write(cdev, M_CAN_TXESC, TXESC_TBDS_64BYTES);
1148 if (cdev->version == 30) {
1149 m_can_write(cdev, M_CAN_TXEFC, (1 << TXEFC_EFS_SHIFT) |
1150 cdev->mcfg[MRAM_TXE].off);
1152 /* Full TX Event FIFO is used */
1153 m_can_write(cdev, M_CAN_TXEFC,
1154 ((cdev->mcfg[MRAM_TXE].num << TXEFC_EFS_SHIFT)
1156 cdev->mcfg[MRAM_TXE].off);
1159 /* rx fifo configuration, blocking mode, fifo size 1 */
1160 m_can_write(cdev, M_CAN_RXF0C,
1161 (cdev->mcfg[MRAM_RXF0].num << RXFC_FS_SHIFT) |
1162 cdev->mcfg[MRAM_RXF0].off);
1164 m_can_write(cdev, M_CAN_RXF1C,
1165 (cdev->mcfg[MRAM_RXF1].num << RXFC_FS_SHIFT) |
1166 cdev->mcfg[MRAM_RXF1].off);
1168 cccr = m_can_read(cdev, M_CAN_CCCR);
1169 test = m_can_read(cdev, M_CAN_TEST);
1171 if (cdev->version == 30) {
1174 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_DAR |
1175 (CCCR_CMR_MASK << CCCR_CMR_SHIFT) |
1176 (CCCR_CME_MASK << CCCR_CME_SHIFT));
1178 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1179 cccr |= CCCR_CME_CANFD_BRS << CCCR_CME_SHIFT;
1182 /* Version 3.1.x or 3.2.x */
1183 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE |
1184 CCCR_NISO | CCCR_DAR);
1186 /* Only 3.2.x has NISO Bit implemented */
1187 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
1190 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1191 cccr |= (CCCR_BRSE | CCCR_FDOE);
1195 if (cdev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1196 cccr |= CCCR_TEST | CCCR_MON;
1200 /* Enable Monitoring (all versions) */
1201 if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1204 /* Disable Auto Retransmission (all versions) */
1205 if (cdev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
1209 m_can_write(cdev, M_CAN_CCCR, cccr);
1210 m_can_write(cdev, M_CAN_TEST, test);
1212 /* Enable interrupts */
1213 m_can_write(cdev, M_CAN_IR, IR_ALL_INT);
1214 if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1215 if (cdev->version == 30)
1216 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1219 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1222 m_can_write(cdev, M_CAN_IE, IR_ALL_INT);
1224 /* route all interrupts to INT0 */
1225 m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0);
1227 /* set bittiming params */
1228 m_can_set_bittiming(dev);
1230 m_can_config_endisable(cdev, false);
1232 if (cdev->ops->init)
1233 cdev->ops->init(cdev);
1236 static void m_can_start(struct net_device *dev)
1238 struct m_can_classdev *cdev = netdev_priv(dev);
1240 /* basic m_can configuration */
1241 m_can_chip_config(dev);
1243 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
1245 m_can_enable_all_interrupts(cdev);
1248 static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
1251 case CAN_MODE_START:
1254 netif_wake_queue(dev);
1263 /* Checks core release number of M_CAN
1264 * returns 0 if an unsupported device is detected
1265 * else it returns the release and step coded as:
1266 * return value = 10 * <release> + 1 * <step>
1268 static int m_can_check_core_release(struct m_can_classdev *cdev)
1275 /* Read Core Release Version and split into version number
1276 * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1;
1278 crel_reg = m_can_read(cdev, M_CAN_CREL);
1279 rel = (u8)((crel_reg & CREL_REL_MASK) >> CREL_REL_SHIFT);
1280 step = (u8)((crel_reg & CREL_STEP_MASK) >> CREL_STEP_SHIFT);
1283 /* M_CAN v3.x.y: create return value */
1286 /* Unsupported M_CAN version */
1293 /* Selectable Non ISO support only in version 3.2.x
1294 * This function checks if the bit is writable.
1296 static bool m_can_niso_supported(struct m_can_classdev *cdev)
1298 u32 cccr_reg, cccr_poll = 0;
1299 int niso_timeout = -ETIMEDOUT;
1302 m_can_config_endisable(cdev, true);
1303 cccr_reg = m_can_read(cdev, M_CAN_CCCR);
1304 cccr_reg |= CCCR_NISO;
1305 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1307 for (i = 0; i <= 10; i++) {
1308 cccr_poll = m_can_read(cdev, M_CAN_CCCR);
1309 if (cccr_poll == cccr_reg) {
1318 cccr_reg &= ~(CCCR_NISO);
1319 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1321 m_can_config_endisable(cdev, false);
1323 /* return false if time out (-ETIMEDOUT), else return true */
1324 return !niso_timeout;
1327 static int m_can_dev_setup(struct m_can_classdev *m_can_dev)
1329 struct net_device *dev = m_can_dev->net;
1332 m_can_version = m_can_check_core_release(m_can_dev);
1333 /* return if unsupported version */
1334 if (!m_can_version) {
1335 dev_err(m_can_dev->dev, "Unsupported version number: %2d",
1340 if (!m_can_dev->is_peripheral)
1341 netif_napi_add(dev, &m_can_dev->napi,
1342 m_can_poll, M_CAN_NAPI_WEIGHT);
1344 /* Shared properties of all M_CAN versions */
1345 m_can_dev->version = m_can_version;
1346 m_can_dev->can.do_set_mode = m_can_set_mode;
1347 m_can_dev->can.do_get_berr_counter = m_can_get_berr_counter;
1349 /* Set M_CAN supported operations */
1350 m_can_dev->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1351 CAN_CTRLMODE_LISTENONLY |
1352 CAN_CTRLMODE_BERR_REPORTING |
1354 CAN_CTRLMODE_ONE_SHOT;
1356 /* Set properties depending on M_CAN version */
1357 switch (m_can_dev->version) {
1359 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */
1360 can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1361 m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
1362 m_can_dev->bit_timing : &m_can_bittiming_const_30X;
1364 m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
1365 m_can_dev->data_timing :
1366 &m_can_data_bittiming_const_30X;
1369 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */
1370 can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1371 m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
1372 m_can_dev->bit_timing : &m_can_bittiming_const_31X;
1374 m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
1375 m_can_dev->data_timing :
1376 &m_can_data_bittiming_const_31X;
1380 /* Support both MCAN version v3.2.x and v3.3.0 */
1381 m_can_dev->can.bittiming_const = m_can_dev->bit_timing ?
1382 m_can_dev->bit_timing : &m_can_bittiming_const_31X;
1384 m_can_dev->can.data_bittiming_const = m_can_dev->data_timing ?
1385 m_can_dev->data_timing :
1386 &m_can_data_bittiming_const_31X;
1388 m_can_dev->can.ctrlmode_supported |=
1389 (m_can_niso_supported(m_can_dev)
1390 ? CAN_CTRLMODE_FD_NON_ISO
1394 dev_err(m_can_dev->dev, "Unsupported version number: %2d",
1395 m_can_dev->version);
1399 if (m_can_dev->ops->init)
1400 m_can_dev->ops->init(m_can_dev);
1405 static void m_can_stop(struct net_device *dev)
1407 struct m_can_classdev *cdev = netdev_priv(dev);
1409 /* disable all interrupts */
1410 m_can_disable_all_interrupts(cdev);
1412 /* Set init mode to disengage from the network */
1413 m_can_config_endisable(cdev, true);
1415 /* set the state as STOPPED */
1416 cdev->can.state = CAN_STATE_STOPPED;
1419 static int m_can_close(struct net_device *dev)
1421 struct m_can_classdev *cdev = netdev_priv(dev);
1423 netif_stop_queue(dev);
1425 if (!cdev->is_peripheral)
1426 napi_disable(&cdev->napi);
1429 m_can_clk_stop(cdev);
1430 free_irq(dev->irq, dev);
1432 if (cdev->is_peripheral) {
1433 cdev->tx_skb = NULL;
1434 destroy_workqueue(cdev->tx_wq);
1439 can_led_event(dev, CAN_LED_EVENT_STOP);
1444 static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx)
1446 struct m_can_classdev *cdev = netdev_priv(dev);
1447 /*get wrap around for loopback skb index */
1448 unsigned int wrap = cdev->can.echo_skb_max;
1451 /* calculate next index */
1452 next_idx = (++putidx >= wrap ? 0 : putidx);
1454 /* check if occupied */
1455 return !!cdev->can.echo_skb[next_idx];
1458 static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
1460 struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data;
1461 struct net_device *dev = cdev->net;
1462 struct sk_buff *skb = cdev->tx_skb;
1463 u32 id, cccr, fdflags;
1467 cdev->tx_skb = NULL;
1469 /* Generate ID field for TX buffer Element */
1470 /* Common to all supported M_CAN versions */
1471 if (cf->can_id & CAN_EFF_FLAG) {
1472 id = cf->can_id & CAN_EFF_MASK;
1475 id = ((cf->can_id & CAN_SFF_MASK) << 18);
1478 if (cf->can_id & CAN_RTR_FLAG)
1481 if (cdev->version == 30) {
1482 netif_stop_queue(dev);
1484 /* message ram configuration */
1485 m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, id);
1486 m_can_fifo_write(cdev, 0, M_CAN_FIFO_DLC,
1487 can_len2dlc(cf->len) << 16);
1489 for (i = 0; i < cf->len; i += 4)
1490 m_can_fifo_write(cdev, 0,
1491 M_CAN_FIFO_DATA(i / 4),
1492 *(u32 *)(cf->data + i));
1494 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1495 cccr = m_can_read(cdev, M_CAN_CCCR);
1496 cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT);
1497 if (can_is_canfd_skb(skb)) {
1498 if (cf->flags & CANFD_BRS)
1499 cccr |= CCCR_CMR_CANFD_BRS <<
1502 cccr |= CCCR_CMR_CANFD <<
1505 cccr |= CCCR_CMR_CAN << CCCR_CMR_SHIFT;
1507 m_can_write(cdev, M_CAN_CCCR, cccr);
1509 m_can_write(cdev, M_CAN_TXBTIE, 0x1);
1511 can_put_echo_skb(skb, dev, 0);
1513 m_can_write(cdev, M_CAN_TXBAR, 0x1);
1514 /* End of xmit function for version 3.0.x */
1516 /* Transmit routine for version >= v3.1.x */
1518 /* Check if FIFO full */
1519 if (m_can_tx_fifo_full(cdev)) {
1520 /* This shouldn't happen */
1521 netif_stop_queue(dev);
1523 "TX queue active although FIFO is full.");
1525 if (cdev->is_peripheral) {
1527 dev->stats.tx_dropped++;
1528 return NETDEV_TX_OK;
1530 return NETDEV_TX_BUSY;
1534 /* get put index for frame */
1535 putidx = ((m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQPI_MASK)
1536 >> TXFQS_TFQPI_SHIFT);
1537 /* Write ID Field to FIFO Element */
1538 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, id);
1540 /* get CAN FD configuration of frame */
1542 if (can_is_canfd_skb(skb)) {
1543 fdflags |= TX_BUF_FDF;
1544 if (cf->flags & CANFD_BRS)
1545 fdflags |= TX_BUF_BRS;
1548 /* Construct DLC Field. Also contains CAN-FD configuration
1549 * use put index of fifo as message marker
1550 * it is used in TX interrupt for
1551 * sending the correct echo frame
1553 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DLC,
1554 ((putidx << TX_BUF_MM_SHIFT) &
1556 (can_len2dlc(cf->len) << 16) |
1557 fdflags | TX_BUF_EFC);
1559 for (i = 0; i < cf->len; i += 4)
1560 m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA(i / 4),
1561 *(u32 *)(cf->data + i));
1563 /* Push loopback echo.
1564 * Will be looped back on TX interrupt based on message marker
1566 can_put_echo_skb(skb, dev, putidx);
1568 /* Enable TX FIFO element to start transfer */
1569 m_can_write(cdev, M_CAN_TXBAR, (1 << putidx));
1571 /* stop network queue if fifo full */
1572 if (m_can_tx_fifo_full(cdev) ||
1573 m_can_next_echo_skb_occupied(dev, putidx))
1574 netif_stop_queue(dev);
1577 return NETDEV_TX_OK;
1580 static void m_can_tx_work_queue(struct work_struct *ws)
1582 struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev,
1585 m_can_tx_handler(cdev);
1588 static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
1589 struct net_device *dev)
1591 struct m_can_classdev *cdev = netdev_priv(dev);
1593 if (can_dropped_invalid_skb(dev, skb))
1594 return NETDEV_TX_OK;
1596 if (cdev->is_peripheral) {
1598 netdev_err(dev, "hard_xmit called while tx busy\n");
1599 return NETDEV_TX_BUSY;
1602 if (cdev->can.state == CAN_STATE_BUS_OFF) {
1605 /* Need to stop the queue to avoid numerous requests
1606 * from being sent. Suggested improvement is to create
1607 * a queueing mechanism that will queue the skbs and
1608 * process them in order.
1611 netif_stop_queue(cdev->net);
1612 queue_work(cdev->tx_wq, &cdev->tx_work);
1616 return m_can_tx_handler(cdev);
1619 return NETDEV_TX_OK;
1622 static int m_can_open(struct net_device *dev)
1624 struct m_can_classdev *cdev = netdev_priv(dev);
1627 err = m_can_clk_start(cdev);
1631 /* open the can device */
1632 err = open_candev(dev);
1634 netdev_err(dev, "failed to open can device\n");
1635 goto exit_disable_clks;
1638 /* register interrupt handler */
1639 if (cdev->is_peripheral) {
1640 cdev->tx_skb = NULL;
1641 cdev->tx_wq = alloc_workqueue("mcan_wq",
1642 WQ_FREEZABLE | WQ_MEM_RECLAIM, 0);
1648 INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);
1650 err = request_threaded_irq(dev->irq, NULL, m_can_isr,
1654 err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
1659 netdev_err(dev, "failed to request interrupt\n");
1663 /* start the m_can controller */
1666 can_led_event(dev, CAN_LED_EVENT_OPEN);
1668 if (!cdev->is_peripheral)
1669 napi_enable(&cdev->napi);
1671 netif_start_queue(dev);
1676 if (cdev->is_peripheral)
1677 destroy_workqueue(cdev->tx_wq);
1681 m_can_clk_stop(cdev);
1685 static const struct net_device_ops m_can_netdev_ops = {
1686 .ndo_open = m_can_open,
1687 .ndo_stop = m_can_close,
1688 .ndo_start_xmit = m_can_start_xmit,
1689 .ndo_change_mtu = can_change_mtu,
1692 static int register_m_can_dev(struct net_device *dev)
1694 dev->flags |= IFF_ECHO; /* we support local echo */
1695 dev->netdev_ops = &m_can_netdev_ops;
1697 return register_candev(dev);
1700 static void m_can_of_parse_mram(struct m_can_classdev *cdev,
1701 const u32 *mram_config_vals)
1703 cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0];
1704 cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1];
1705 cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off +
1706 cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
1707 cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2];
1708 cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off +
1709 cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
1710 cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] &
1711 (RXFC_FS_MASK >> RXFC_FS_SHIFT);
1712 cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off +
1713 cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
1714 cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] &
1715 (RXFC_FS_MASK >> RXFC_FS_SHIFT);
1716 cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off +
1717 cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
1718 cdev->mcfg[MRAM_RXB].num = mram_config_vals[5];
1719 cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off +
1720 cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
1721 cdev->mcfg[MRAM_TXE].num = mram_config_vals[6];
1722 cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off +
1723 cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
1724 cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] &
1725 (TXBC_NDTB_MASK >> TXBC_NDTB_SHIFT);
1728 "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",
1729 cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num,
1730 cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num,
1731 cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num,
1732 cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num,
1733 cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num,
1734 cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num,
1735 cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num);
1738 void m_can_init_ram(struct m_can_classdev *cdev)
1742 /* initialize the entire Message RAM in use to avoid possible
1743 * ECC/parity checksum errors when reading an uninitialized buffer
1745 start = cdev->mcfg[MRAM_SIDF].off;
1746 end = cdev->mcfg[MRAM_TXB].off +
1747 cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;
1749 for (i = start; i < end; i += 4)
1750 m_can_fifo_write_no_off(cdev, i, 0x0);
1752 EXPORT_SYMBOL_GPL(m_can_init_ram);
1754 int m_can_class_get_clocks(struct m_can_classdev *m_can_dev)
1758 m_can_dev->hclk = devm_clk_get(m_can_dev->dev, "hclk");
1759 m_can_dev->cclk = devm_clk_get(m_can_dev->dev, "cclk");
1761 if (IS_ERR(m_can_dev->cclk)) {
1762 dev_err(m_can_dev->dev, "no clock found\n");
1768 EXPORT_SYMBOL_GPL(m_can_class_get_clocks);
1770 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev)
1772 struct m_can_classdev *class_dev = NULL;
1773 u32 mram_config_vals[MRAM_CFG_LEN];
1774 struct net_device *net_dev;
1778 ret = fwnode_property_read_u32_array(dev_fwnode(dev),
1781 sizeof(mram_config_vals) / 4);
1783 dev_err(dev, "Could not get Message RAM configuration.");
1788 * Defines the total amount of echo buffers for loopback
1790 tx_fifo_size = mram_config_vals[7];
1792 /* allocate the m_can device */
1793 net_dev = alloc_candev(sizeof(*class_dev), tx_fifo_size);
1795 dev_err(dev, "Failed to allocate CAN device");
1799 class_dev = netdev_priv(net_dev);
1801 dev_err(dev, "Failed to init netdev cdevate");
1805 class_dev->net = net_dev;
1806 class_dev->dev = dev;
1807 SET_NETDEV_DEV(net_dev, dev);
1809 m_can_of_parse_mram(class_dev, mram_config_vals);
1813 EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);
1815 void m_can_class_free_dev(struct net_device *net)
1819 EXPORT_SYMBOL_GPL(m_can_class_free_dev);
1821 int m_can_class_register(struct m_can_classdev *m_can_dev)
1825 if (m_can_dev->pm_clock_support) {
1826 pm_runtime_enable(m_can_dev->dev);
1827 ret = m_can_clk_start(m_can_dev);
1829 goto pm_runtime_fail;
1832 ret = m_can_dev_setup(m_can_dev);
1836 ret = register_m_can_dev(m_can_dev->net);
1838 dev_err(m_can_dev->dev, "registering %s failed (err=%d)\n",
1839 m_can_dev->net->name, ret);
1843 devm_can_led_init(m_can_dev->net);
1845 of_can_transceiver(m_can_dev->net);
1847 dev_info(m_can_dev->dev, "%s device registered (irq=%d, version=%d)\n",
1848 KBUILD_MODNAME, m_can_dev->net->irq, m_can_dev->version);
1851 * Stop clocks. They will be reactivated once the M_CAN device is opened
1854 m_can_clk_stop(m_can_dev);
1857 if (m_can_dev->pm_clock_support)
1858 pm_runtime_disable(m_can_dev->dev);
1863 EXPORT_SYMBOL_GPL(m_can_class_register);
1865 int m_can_class_suspend(struct device *dev)
1867 struct net_device *ndev = dev_get_drvdata(dev);
1868 struct m_can_classdev *cdev = netdev_priv(ndev);
1870 if (netif_running(ndev)) {
1871 netif_stop_queue(ndev);
1872 netif_device_detach(ndev);
1874 m_can_clk_stop(cdev);
1877 pinctrl_pm_select_sleep_state(dev);
1879 cdev->can.state = CAN_STATE_SLEEPING;
1883 EXPORT_SYMBOL_GPL(m_can_class_suspend);
1885 int m_can_class_resume(struct device *dev)
1887 struct net_device *ndev = dev_get_drvdata(dev);
1888 struct m_can_classdev *cdev = netdev_priv(ndev);
1890 pinctrl_pm_select_default_state(dev);
1892 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
1894 if (netif_running(ndev)) {
1897 ret = m_can_clk_start(cdev);
1901 m_can_init_ram(cdev);
1903 netif_device_attach(ndev);
1904 netif_start_queue(ndev);
1909 EXPORT_SYMBOL_GPL(m_can_class_resume);
1911 void m_can_class_unregister(struct m_can_classdev *m_can_dev)
1913 unregister_candev(m_can_dev->net);
1915 EXPORT_SYMBOL_GPL(m_can_class_unregister);
1917 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
1918 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
1919 MODULE_LICENSE("GPL v2");
1920 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");