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/ethtool.h>
13 #include <linux/interrupt.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/netdevice.h>
19 #include <linux/of_device.h>
20 #include <linux/platform_device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/iopoll.h>
23 #include <linux/can/dev.h>
24 #include <linux/pinctrl/consumer.h>
25 #include <linux/phy/phy.h>
29 /* registers definition */
45 /* TDCR Register only available for version >=3.1.x */
81 /* message ram configuration data length */
82 #define MRAM_CFG_LEN 8
84 /* Core Release Register (CREL) */
85 #define CREL_REL_MASK GENMASK(31, 28)
86 #define CREL_STEP_MASK GENMASK(27, 24)
87 #define CREL_SUBSTEP_MASK GENMASK(23, 20)
89 /* Data Bit Timing & Prescaler Register (DBTP) */
90 #define DBTP_TDC BIT(23)
91 #define DBTP_DBRP_MASK GENMASK(20, 16)
92 #define DBTP_DTSEG1_MASK GENMASK(12, 8)
93 #define DBTP_DTSEG2_MASK GENMASK(7, 4)
94 #define DBTP_DSJW_MASK GENMASK(3, 0)
96 /* Transmitter Delay Compensation Register (TDCR) */
97 #define TDCR_TDCO_MASK GENMASK(14, 8)
98 #define TDCR_TDCF_MASK GENMASK(6, 0)
100 /* Test Register (TEST) */
101 #define TEST_LBCK BIT(4)
103 /* CC Control Register (CCCR) */
104 #define CCCR_TXP BIT(14)
105 #define CCCR_TEST BIT(7)
106 #define CCCR_DAR BIT(6)
107 #define CCCR_MON BIT(5)
108 #define CCCR_CSR BIT(4)
109 #define CCCR_CSA BIT(3)
110 #define CCCR_ASM BIT(2)
111 #define CCCR_CCE BIT(1)
112 #define CCCR_INIT BIT(0)
113 /* for version 3.0.x */
114 #define CCCR_CMR_MASK GENMASK(11, 10)
115 #define CCCR_CMR_CANFD 0x1
116 #define CCCR_CMR_CANFD_BRS 0x2
117 #define CCCR_CMR_CAN 0x3
118 #define CCCR_CME_MASK GENMASK(9, 8)
119 #define CCCR_CME_CAN 0
120 #define CCCR_CME_CANFD 0x1
121 #define CCCR_CME_CANFD_BRS 0x2
122 /* for version >=3.1.x */
123 #define CCCR_EFBI BIT(13)
124 #define CCCR_PXHD BIT(12)
125 #define CCCR_BRSE BIT(9)
126 #define CCCR_FDOE BIT(8)
127 /* for version >=3.2.x */
128 #define CCCR_NISO BIT(15)
129 /* for version >=3.3.x */
130 #define CCCR_WMM BIT(11)
131 #define CCCR_UTSU BIT(10)
133 /* Nominal Bit Timing & Prescaler Register (NBTP) */
134 #define NBTP_NSJW_MASK GENMASK(31, 25)
135 #define NBTP_NBRP_MASK GENMASK(24, 16)
136 #define NBTP_NTSEG1_MASK GENMASK(15, 8)
137 #define NBTP_NTSEG2_MASK GENMASK(6, 0)
139 /* Timestamp Counter Configuration Register (TSCC) */
140 #define TSCC_TCP_MASK GENMASK(19, 16)
141 #define TSCC_TSS_MASK GENMASK(1, 0)
142 #define TSCC_TSS_DISABLE 0x0
143 #define TSCC_TSS_INTERNAL 0x1
144 #define TSCC_TSS_EXTERNAL 0x2
146 /* Timestamp Counter Value Register (TSCV) */
147 #define TSCV_TSC_MASK GENMASK(15, 0)
149 /* Error Counter Register (ECR) */
150 #define ECR_RP BIT(15)
151 #define ECR_REC_MASK GENMASK(14, 8)
152 #define ECR_TEC_MASK GENMASK(7, 0)
154 /* Protocol Status Register (PSR) */
155 #define PSR_BO BIT(7)
156 #define PSR_EW BIT(6)
157 #define PSR_EP BIT(5)
158 #define PSR_LEC_MASK GENMASK(2, 0)
160 /* Interrupt Register (IR) */
161 #define IR_ALL_INT 0xffffffff
163 /* Renamed bits for versions > 3.1.x */
164 #define IR_ARA BIT(29)
165 #define IR_PED BIT(28)
166 #define IR_PEA BIT(27)
168 /* Bits for version 3.0.x */
169 #define IR_STE BIT(31)
170 #define IR_FOE BIT(30)
171 #define IR_ACKE BIT(29)
172 #define IR_BE BIT(28)
173 #define IR_CRCE BIT(27)
174 #define IR_WDI BIT(26)
175 #define IR_BO BIT(25)
176 #define IR_EW BIT(24)
177 #define IR_EP BIT(23)
178 #define IR_ELO BIT(22)
179 #define IR_BEU BIT(21)
180 #define IR_BEC BIT(20)
181 #define IR_DRX BIT(19)
182 #define IR_TOO BIT(18)
183 #define IR_MRAF BIT(17)
184 #define IR_TSW BIT(16)
185 #define IR_TEFL BIT(15)
186 #define IR_TEFF BIT(14)
187 #define IR_TEFW BIT(13)
188 #define IR_TEFN BIT(12)
189 #define IR_TFE BIT(11)
190 #define IR_TCF BIT(10)
192 #define IR_HPM BIT(8)
193 #define IR_RF1L BIT(7)
194 #define IR_RF1F BIT(6)
195 #define IR_RF1W BIT(5)
196 #define IR_RF1N BIT(4)
197 #define IR_RF0L BIT(3)
198 #define IR_RF0F BIT(2)
199 #define IR_RF0W BIT(1)
200 #define IR_RF0N BIT(0)
201 #define IR_ERR_STATE (IR_BO | IR_EW | IR_EP)
203 /* Interrupts for version 3.0.x */
204 #define IR_ERR_LEC_30X (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
205 #define IR_ERR_BUS_30X (IR_ERR_LEC_30X | IR_WDI | IR_BEU | IR_BEC | \
206 IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \
208 #define IR_ERR_ALL_30X (IR_ERR_STATE | IR_ERR_BUS_30X)
210 /* Interrupts for version >= 3.1.x */
211 #define IR_ERR_LEC_31X (IR_PED | IR_PEA)
212 #define IR_ERR_BUS_31X (IR_ERR_LEC_31X | IR_WDI | IR_BEU | IR_BEC | \
213 IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \
215 #define IR_ERR_ALL_31X (IR_ERR_STATE | IR_ERR_BUS_31X)
217 /* Interrupt Line Select (ILS) */
218 #define ILS_ALL_INT0 0x0
219 #define ILS_ALL_INT1 0xFFFFFFFF
221 /* Interrupt Line Enable (ILE) */
222 #define ILE_EINT1 BIT(1)
223 #define ILE_EINT0 BIT(0)
225 /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
226 #define RXFC_FWM_MASK GENMASK(30, 24)
227 #define RXFC_FS_MASK GENMASK(22, 16)
229 /* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
230 #define RXFS_RFL BIT(25)
231 #define RXFS_FF BIT(24)
232 #define RXFS_FPI_MASK GENMASK(21, 16)
233 #define RXFS_FGI_MASK GENMASK(13, 8)
234 #define RXFS_FFL_MASK GENMASK(6, 0)
236 /* Rx Buffer / FIFO Element Size Configuration (RXESC) */
237 #define RXESC_RBDS_MASK GENMASK(10, 8)
238 #define RXESC_F1DS_MASK GENMASK(6, 4)
239 #define RXESC_F0DS_MASK GENMASK(2, 0)
240 #define RXESC_64B 0x7
242 /* Tx Buffer Configuration (TXBC) */
243 #define TXBC_TFQS_MASK GENMASK(29, 24)
244 #define TXBC_NDTB_MASK GENMASK(21, 16)
246 /* Tx FIFO/Queue Status (TXFQS) */
247 #define TXFQS_TFQF BIT(21)
248 #define TXFQS_TFQPI_MASK GENMASK(20, 16)
249 #define TXFQS_TFGI_MASK GENMASK(12, 8)
250 #define TXFQS_TFFL_MASK GENMASK(5, 0)
252 /* Tx Buffer Element Size Configuration (TXESC) */
253 #define TXESC_TBDS_MASK GENMASK(2, 0)
254 #define TXESC_TBDS_64B 0x7
256 /* Tx Event FIFO Configuration (TXEFC) */
257 #define TXEFC_EFS_MASK GENMASK(21, 16)
259 /* Tx Event FIFO Status (TXEFS) */
260 #define TXEFS_TEFL BIT(25)
261 #define TXEFS_EFF BIT(24)
262 #define TXEFS_EFGI_MASK GENMASK(12, 8)
263 #define TXEFS_EFFL_MASK GENMASK(5, 0)
265 /* Tx Event FIFO Acknowledge (TXEFA) */
266 #define TXEFA_EFAI_MASK GENMASK(4, 0)
268 /* Message RAM Configuration (in bytes) */
269 #define SIDF_ELEMENT_SIZE 4
270 #define XIDF_ELEMENT_SIZE 8
271 #define RXF0_ELEMENT_SIZE 72
272 #define RXF1_ELEMENT_SIZE 72
273 #define RXB_ELEMENT_SIZE 72
274 #define TXE_ELEMENT_SIZE 8
275 #define TXB_ELEMENT_SIZE 72
277 /* Message RAM Elements */
278 #define M_CAN_FIFO_ID 0x0
279 #define M_CAN_FIFO_DLC 0x4
280 #define M_CAN_FIFO_DATA 0x8
282 /* Rx Buffer Element */
284 #define RX_BUF_ESI BIT(31)
285 #define RX_BUF_XTD BIT(30)
286 #define RX_BUF_RTR BIT(29)
288 #define RX_BUF_ANMF BIT(31)
289 #define RX_BUF_FDF BIT(21)
290 #define RX_BUF_BRS BIT(20)
291 #define RX_BUF_RXTS_MASK GENMASK(15, 0)
293 /* Tx Buffer Element */
295 #define TX_BUF_ESI BIT(31)
296 #define TX_BUF_XTD BIT(30)
297 #define TX_BUF_RTR BIT(29)
299 #define TX_BUF_EFC BIT(23)
300 #define TX_BUF_FDF BIT(21)
301 #define TX_BUF_BRS BIT(20)
302 #define TX_BUF_MM_MASK GENMASK(31, 24)
303 #define TX_BUF_DLC_MASK GENMASK(19, 16)
305 /* Tx event FIFO Element */
307 #define TX_EVENT_MM_MASK GENMASK(31, 24)
308 #define TX_EVENT_TXTS_MASK GENMASK(15, 0)
310 /* The ID and DLC registers are adjacent in M_CAN FIFO memory,
311 * and we can save a (potentially slow) bus round trip by combining
312 * reads and writes to them.
319 static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg)
321 return cdev->ops->read_reg(cdev, reg);
324 static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg,
327 cdev->ops->write_reg(cdev, reg, val);
331 m_can_fifo_read(struct m_can_classdev *cdev,
332 u32 fgi, unsigned int offset, void *val, size_t val_count)
334 u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE +
340 return cdev->ops->read_fifo(cdev, addr_offset, val, val_count);
344 m_can_fifo_write(struct m_can_classdev *cdev,
345 u32 fpi, unsigned int offset, const void *val, size_t val_count)
347 u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE +
353 return cdev->ops->write_fifo(cdev, addr_offset, val, val_count);
356 static inline int m_can_fifo_write_no_off(struct m_can_classdev *cdev,
359 return cdev->ops->write_fifo(cdev, fpi, &val, 1);
363 m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset, u32 *val)
365 u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE +
368 return cdev->ops->read_fifo(cdev, addr_offset, val, 1);
371 static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev)
373 return !!(m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQF);
376 static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
378 u32 cccr = m_can_read(cdev, M_CAN_CCCR);
382 /* Clear the Clock stop request if it was set */
387 /* enable m_can configuration */
388 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT);
390 /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
391 m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
393 m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
396 /* there's a delay for module initialization */
398 val = CCCR_INIT | CCCR_CCE;
400 while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
402 netdev_warn(cdev->net, "Failed to init module\n");
410 static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev)
412 /* Only interrupt line 0 is used in this driver */
413 m_can_write(cdev, M_CAN_ILE, ILE_EINT0);
416 static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev)
418 m_can_write(cdev, M_CAN_ILE, 0x0);
421 /* Retrieve internal timestamp counter from TSCV.TSC, and shift it to 32-bit
424 static u32 m_can_get_timestamp(struct m_can_classdev *cdev)
429 tscv = m_can_read(cdev, M_CAN_TSCV);
430 tsc = FIELD_GET(TSCV_TSC_MASK, tscv);
435 static void m_can_clean(struct net_device *net)
437 struct m_can_classdev *cdev = netdev_priv(net);
442 net->stats.tx_errors++;
443 if (cdev->version > 30)
444 putidx = FIELD_GET(TXFQS_TFQPI_MASK,
445 m_can_read(cdev, M_CAN_TXFQS));
447 can_free_echo_skb(cdev->net, putidx, NULL);
452 /* For peripherals, pass skb to rx-offload, which will push skb from
453 * napi. For non-peripherals, RX is done in napi already, so push
454 * directly. timestamp is used to ensure good skb ordering in
455 * rx-offload and is ignored for non-peripherals.
457 static void m_can_receive_skb(struct m_can_classdev *cdev,
461 if (cdev->is_peripheral) {
462 struct net_device_stats *stats = &cdev->net->stats;
465 err = can_rx_offload_queue_timestamp(&cdev->offload, skb,
468 stats->rx_fifo_errors++;
470 netif_receive_skb(skb);
474 static int m_can_read_fifo(struct net_device *dev, u32 rxfs)
476 struct net_device_stats *stats = &dev->stats;
477 struct m_can_classdev *cdev = netdev_priv(dev);
478 struct canfd_frame *cf;
480 struct id_and_dlc fifo_header;
485 /* calculate the fifo get index for where to read data */
486 fgi = FIELD_GET(RXFS_FGI_MASK, rxfs);
487 err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID, &fifo_header, 2);
491 if (fifo_header.dlc & RX_BUF_FDF)
492 skb = alloc_canfd_skb(dev, &cf);
494 skb = alloc_can_skb(dev, (struct can_frame **)&cf);
500 if (fifo_header.dlc & RX_BUF_FDF)
501 cf->len = can_fd_dlc2len((fifo_header.dlc >> 16) & 0x0F);
503 cf->len = can_cc_dlc2len((fifo_header.dlc >> 16) & 0x0F);
505 if (fifo_header.id & RX_BUF_XTD)
506 cf->can_id = (fifo_header.id & CAN_EFF_MASK) | CAN_EFF_FLAG;
508 cf->can_id = (fifo_header.id >> 18) & CAN_SFF_MASK;
510 if (fifo_header.id & RX_BUF_ESI) {
511 cf->flags |= CANFD_ESI;
512 netdev_dbg(dev, "ESI Error\n");
515 if (!(fifo_header.dlc & RX_BUF_FDF) && (fifo_header.id & RX_BUF_RTR)) {
516 cf->can_id |= CAN_RTR_FLAG;
518 if (fifo_header.dlc & RX_BUF_BRS)
519 cf->flags |= CANFD_BRS;
521 err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DATA,
522 cf->data, DIV_ROUND_UP(cf->len, 4));
526 stats->rx_bytes += cf->len;
530 /* acknowledge rx fifo 0 */
531 m_can_write(cdev, M_CAN_RXF0A, fgi);
533 timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc) << 16;
535 m_can_receive_skb(cdev, skb, timestamp);
542 netdev_err(dev, "FIFO read returned %d\n", err);
546 static int m_can_do_rx_poll(struct net_device *dev, int quota)
548 struct m_can_classdev *cdev = netdev_priv(dev);
553 rxfs = m_can_read(cdev, M_CAN_RXF0S);
554 if (!(rxfs & RXFS_FFL_MASK)) {
555 netdev_dbg(dev, "no messages in fifo0\n");
559 while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
560 err = m_can_read_fifo(dev, rxfs);
566 rxfs = m_can_read(cdev, M_CAN_RXF0S);
572 static int m_can_handle_lost_msg(struct net_device *dev)
574 struct m_can_classdev *cdev = netdev_priv(dev);
575 struct net_device_stats *stats = &dev->stats;
577 struct can_frame *frame;
580 netdev_err(dev, "msg lost in rxf0\n");
583 stats->rx_over_errors++;
585 skb = alloc_can_err_skb(dev, &frame);
589 frame->can_id |= CAN_ERR_CRTL;
590 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
592 if (cdev->is_peripheral)
593 timestamp = m_can_get_timestamp(cdev);
595 m_can_receive_skb(cdev, skb, timestamp);
600 static int m_can_handle_lec_err(struct net_device *dev,
601 enum m_can_lec_type lec_type)
603 struct m_can_classdev *cdev = netdev_priv(dev);
604 struct net_device_stats *stats = &dev->stats;
605 struct can_frame *cf;
609 cdev->can.can_stats.bus_error++;
612 /* propagate the error condition to the CAN stack */
613 skb = alloc_can_err_skb(dev, &cf);
617 /* check for 'last error code' which tells us the
618 * type of the last error to occur on the CAN bus
620 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
623 case LEC_STUFF_ERROR:
624 netdev_dbg(dev, "stuff error\n");
625 cf->data[2] |= CAN_ERR_PROT_STUFF;
628 netdev_dbg(dev, "form error\n");
629 cf->data[2] |= CAN_ERR_PROT_FORM;
632 netdev_dbg(dev, "ack error\n");
633 cf->data[3] = CAN_ERR_PROT_LOC_ACK;
636 netdev_dbg(dev, "bit1 error\n");
637 cf->data[2] |= CAN_ERR_PROT_BIT1;
640 netdev_dbg(dev, "bit0 error\n");
641 cf->data[2] |= CAN_ERR_PROT_BIT0;
644 netdev_dbg(dev, "CRC error\n");
645 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
651 if (cdev->is_peripheral)
652 timestamp = m_can_get_timestamp(cdev);
654 m_can_receive_skb(cdev, skb, timestamp);
659 static int __m_can_get_berr_counter(const struct net_device *dev,
660 struct can_berr_counter *bec)
662 struct m_can_classdev *cdev = netdev_priv(dev);
665 ecr = m_can_read(cdev, M_CAN_ECR);
666 bec->rxerr = FIELD_GET(ECR_REC_MASK, ecr);
667 bec->txerr = FIELD_GET(ECR_TEC_MASK, ecr);
672 static int m_can_clk_start(struct m_can_classdev *cdev)
674 if (cdev->pm_clock_support == 0)
677 return pm_runtime_resume_and_get(cdev->dev);
680 static void m_can_clk_stop(struct m_can_classdev *cdev)
682 if (cdev->pm_clock_support)
683 pm_runtime_put_sync(cdev->dev);
686 static int m_can_get_berr_counter(const struct net_device *dev,
687 struct can_berr_counter *bec)
689 struct m_can_classdev *cdev = netdev_priv(dev);
692 err = m_can_clk_start(cdev);
696 __m_can_get_berr_counter(dev, bec);
698 m_can_clk_stop(cdev);
703 static int m_can_handle_state_change(struct net_device *dev,
704 enum can_state new_state)
706 struct m_can_classdev *cdev = netdev_priv(dev);
707 struct can_frame *cf;
709 struct can_berr_counter bec;
714 case CAN_STATE_ERROR_WARNING:
715 /* error warning state */
716 cdev->can.can_stats.error_warning++;
717 cdev->can.state = CAN_STATE_ERROR_WARNING;
719 case CAN_STATE_ERROR_PASSIVE:
720 /* error passive state */
721 cdev->can.can_stats.error_passive++;
722 cdev->can.state = CAN_STATE_ERROR_PASSIVE;
724 case CAN_STATE_BUS_OFF:
726 cdev->can.state = CAN_STATE_BUS_OFF;
727 m_can_disable_all_interrupts(cdev);
728 cdev->can.can_stats.bus_off++;
735 /* propagate the error condition to the CAN stack */
736 skb = alloc_can_err_skb(dev, &cf);
740 __m_can_get_berr_counter(dev, &bec);
743 case CAN_STATE_ERROR_WARNING:
744 /* error warning state */
745 cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
746 cf->data[1] = (bec.txerr > bec.rxerr) ?
747 CAN_ERR_CRTL_TX_WARNING :
748 CAN_ERR_CRTL_RX_WARNING;
749 cf->data[6] = bec.txerr;
750 cf->data[7] = bec.rxerr;
752 case CAN_STATE_ERROR_PASSIVE:
753 /* error passive state */
754 cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
755 ecr = m_can_read(cdev, M_CAN_ECR);
757 cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
759 cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
760 cf->data[6] = bec.txerr;
761 cf->data[7] = bec.rxerr;
763 case CAN_STATE_BUS_OFF:
765 cf->can_id |= CAN_ERR_BUSOFF;
771 if (cdev->is_peripheral)
772 timestamp = m_can_get_timestamp(cdev);
774 m_can_receive_skb(cdev, skb, timestamp);
779 static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
781 struct m_can_classdev *cdev = netdev_priv(dev);
784 if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) {
785 netdev_dbg(dev, "entered error warning state\n");
786 work_done += m_can_handle_state_change(dev,
787 CAN_STATE_ERROR_WARNING);
790 if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) {
791 netdev_dbg(dev, "entered error passive state\n");
792 work_done += m_can_handle_state_change(dev,
793 CAN_STATE_ERROR_PASSIVE);
796 if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) {
797 netdev_dbg(dev, "entered error bus off state\n");
798 work_done += m_can_handle_state_change(dev,
805 static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
807 if (irqstatus & IR_WDI)
808 netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
809 if (irqstatus & IR_BEU)
810 netdev_err(dev, "Bit Error Uncorrected\n");
811 if (irqstatus & IR_BEC)
812 netdev_err(dev, "Bit Error Corrected\n");
813 if (irqstatus & IR_TOO)
814 netdev_err(dev, "Timeout reached\n");
815 if (irqstatus & IR_MRAF)
816 netdev_err(dev, "Message RAM access failure occurred\n");
819 static inline bool is_lec_err(u8 lec)
821 return lec != LEC_NO_ERROR && lec != LEC_NO_CHANGE;
824 static inline bool m_can_is_protocol_err(u32 irqstatus)
826 return irqstatus & IR_ERR_LEC_31X;
829 static int m_can_handle_protocol_error(struct net_device *dev, u32 irqstatus)
831 struct net_device_stats *stats = &dev->stats;
832 struct m_can_classdev *cdev = netdev_priv(dev);
833 struct can_frame *cf;
837 /* propagate the error condition to the CAN stack */
838 skb = alloc_can_err_skb(dev, &cf);
840 /* update tx error stats since there is protocol error */
843 /* update arbitration lost status */
844 if (cdev->version >= 31 && (irqstatus & IR_PEA)) {
845 netdev_dbg(dev, "Protocol error in Arbitration fail\n");
846 cdev->can.can_stats.arbitration_lost++;
848 cf->can_id |= CAN_ERR_LOSTARB;
849 cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC;
853 if (unlikely(!skb)) {
854 netdev_dbg(dev, "allocation of skb failed\n");
858 if (cdev->is_peripheral)
859 timestamp = m_can_get_timestamp(cdev);
861 m_can_receive_skb(cdev, skb, timestamp);
866 static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
869 struct m_can_classdev *cdev = netdev_priv(dev);
872 if (irqstatus & IR_RF0L)
873 work_done += m_can_handle_lost_msg(dev);
875 /* handle lec errors on the bus */
876 if (cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) {
877 u8 lec = FIELD_GET(PSR_LEC_MASK, psr);
880 work_done += m_can_handle_lec_err(dev, lec);
883 /* handle protocol errors in arbitration phase */
884 if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
885 m_can_is_protocol_err(irqstatus))
886 work_done += m_can_handle_protocol_error(dev, irqstatus);
888 /* other unproccessed error interrupts */
889 m_can_handle_other_err(dev, irqstatus);
894 static int m_can_rx_handler(struct net_device *dev, int quota)
896 struct m_can_classdev *cdev = netdev_priv(dev);
901 irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR);
905 /* Errata workaround for issue "Needless activation of MRAF irq"
906 * During frame reception while the MCAN is in Error Passive state
907 * and the Receive Error Counter has the value MCAN_ECR.REC = 127,
908 * it may happen that MCAN_IR.MRAF is set although there was no
909 * Message RAM access failure.
910 * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated
911 * The Message RAM Access Failure interrupt routine needs to check
912 * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127.
913 * In this case, reset MCAN_IR.MRAF. No further action is required.
915 if (cdev->version <= 31 && irqstatus & IR_MRAF &&
916 m_can_read(cdev, M_CAN_ECR) & ECR_RP) {
917 struct can_berr_counter bec;
919 __m_can_get_berr_counter(dev, &bec);
920 if (bec.rxerr == 127) {
921 m_can_write(cdev, M_CAN_IR, IR_MRAF);
922 irqstatus &= ~IR_MRAF;
926 psr = m_can_read(cdev, M_CAN_PSR);
928 if (irqstatus & IR_ERR_STATE)
929 work_done += m_can_handle_state_errors(dev, psr);
931 if (irqstatus & IR_ERR_BUS_30X)
932 work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
934 if (irqstatus & IR_RF0N) {
935 rx_work_or_err = m_can_do_rx_poll(dev, (quota - work_done));
936 if (rx_work_or_err < 0)
937 return rx_work_or_err;
939 work_done += rx_work_or_err;
945 static int m_can_rx_peripheral(struct net_device *dev)
947 struct m_can_classdev *cdev = netdev_priv(dev);
950 work_done = m_can_rx_handler(dev, NAPI_POLL_WEIGHT);
952 /* Don't re-enable interrupts if the driver had a fatal error
953 * (e.g., FIFO read failure).
956 m_can_enable_all_interrupts(cdev);
961 static int m_can_poll(struct napi_struct *napi, int quota)
963 struct net_device *dev = napi->dev;
964 struct m_can_classdev *cdev = netdev_priv(dev);
967 work_done = m_can_rx_handler(dev, quota);
969 /* Don't re-enable interrupts if the driver had a fatal error
970 * (e.g., FIFO read failure).
972 if (work_done >= 0 && work_done < quota) {
973 napi_complete_done(napi, work_done);
974 m_can_enable_all_interrupts(cdev);
980 /* Echo tx skb and update net stats. Peripherals use rx-offload for
981 * echo. timestamp is used for peripherals to ensure correct ordering
982 * by rx-offload, and is ignored for non-peripherals.
984 static void m_can_tx_update_stats(struct m_can_classdev *cdev,
985 unsigned int msg_mark,
988 struct net_device *dev = cdev->net;
989 struct net_device_stats *stats = &dev->stats;
991 if (cdev->is_peripheral)
993 can_rx_offload_get_echo_skb(&cdev->offload,
998 stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL);
1000 stats->tx_packets++;
1003 static int m_can_echo_tx_event(struct net_device *dev)
1009 unsigned int msg_mark;
1011 struct m_can_classdev *cdev = netdev_priv(dev);
1013 /* read tx event fifo status */
1014 m_can_txefs = m_can_read(cdev, M_CAN_TXEFS);
1016 /* Get Tx Event fifo element count */
1017 txe_count = FIELD_GET(TXEFS_EFFL_MASK, m_can_txefs);
1019 /* Get and process all sent elements */
1020 for (i = 0; i < txe_count; i++) {
1021 u32 txe, timestamp = 0;
1024 /* retrieve get index */
1025 fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_read(cdev, M_CAN_TXEFS));
1027 /* get message marker, timestamp */
1028 err = m_can_txe_fifo_read(cdev, fgi, 4, &txe);
1030 netdev_err(dev, "TXE FIFO read returned %d\n", err);
1034 msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe);
1035 timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe) << 16;
1037 /* ack txe element */
1038 m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK,
1042 m_can_tx_update_stats(cdev, msg_mark, timestamp);
1048 static irqreturn_t m_can_isr(int irq, void *dev_id)
1050 struct net_device *dev = (struct net_device *)dev_id;
1051 struct m_can_classdev *cdev = netdev_priv(dev);
1054 if (pm_runtime_suspended(cdev->dev))
1056 ir = m_can_read(cdev, M_CAN_IR);
1061 if (ir & IR_ALL_INT)
1062 m_can_write(cdev, M_CAN_IR, ir);
1064 if (cdev->ops->clear_interrupts)
1065 cdev->ops->clear_interrupts(cdev);
1067 /* schedule NAPI in case of
1069 * - state change IRQ
1070 * - bus error IRQ and bus error reporting
1072 if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) {
1073 cdev->irqstatus = ir;
1074 m_can_disable_all_interrupts(cdev);
1075 if (!cdev->is_peripheral)
1076 napi_schedule(&cdev->napi);
1077 else if (m_can_rx_peripheral(dev) < 0)
1081 if (cdev->version == 30) {
1083 /* Transmission Complete Interrupt*/
1086 if (cdev->is_peripheral)
1087 timestamp = m_can_get_timestamp(cdev);
1088 m_can_tx_update_stats(cdev, 0, timestamp);
1089 netif_wake_queue(dev);
1093 /* New TX FIFO Element arrived */
1094 if (m_can_echo_tx_event(dev) != 0)
1097 if (netif_queue_stopped(dev) &&
1098 !m_can_tx_fifo_full(cdev))
1099 netif_wake_queue(dev);
1103 if (cdev->is_peripheral)
1104 can_rx_offload_threaded_irq_finish(&cdev->offload);
1109 m_can_disable_all_interrupts(cdev);
1113 static const struct can_bittiming_const m_can_bittiming_const_30X = {
1114 .name = KBUILD_MODNAME,
1115 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1117 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1125 static const struct can_bittiming_const m_can_data_bittiming_const_30X = {
1126 .name = KBUILD_MODNAME,
1127 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1129 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1137 static const struct can_bittiming_const m_can_bittiming_const_31X = {
1138 .name = KBUILD_MODNAME,
1139 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
1141 .tseg2_min = 2, /* Time segment 2 = phase_seg2 */
1149 static const struct can_bittiming_const m_can_data_bittiming_const_31X = {
1150 .name = KBUILD_MODNAME,
1151 .tseg1_min = 1, /* Time segment 1 = prop_seg + phase_seg1 */
1153 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
1161 static int m_can_set_bittiming(struct net_device *dev)
1163 struct m_can_classdev *cdev = netdev_priv(dev);
1164 const struct can_bittiming *bt = &cdev->can.bittiming;
1165 const struct can_bittiming *dbt = &cdev->can.data_bittiming;
1166 u16 brp, sjw, tseg1, tseg2;
1171 tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
1172 tseg2 = bt->phase_seg2 - 1;
1173 reg_btp = FIELD_PREP(NBTP_NBRP_MASK, brp) |
1174 FIELD_PREP(NBTP_NSJW_MASK, sjw) |
1175 FIELD_PREP(NBTP_NTSEG1_MASK, tseg1) |
1176 FIELD_PREP(NBTP_NTSEG2_MASK, tseg2);
1177 m_can_write(cdev, M_CAN_NBTP, reg_btp);
1179 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1183 tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
1184 tseg2 = dbt->phase_seg2 - 1;
1186 /* TDC is only needed for bitrates beyond 2.5 MBit/s.
1187 * This is mentioned in the "Bit Time Requirements for CAN FD"
1188 * paper presented at the International CAN Conference 2013
1190 if (dbt->bitrate > 2500000) {
1193 /* Use the same value of secondary sampling point
1194 * as the data sampling point
1196 ssp = dbt->sample_point;
1198 /* Equation based on Bosch's M_CAN User Manual's
1199 * Transmitter Delay Compensation Section
1201 tdco = (cdev->can.clock.freq / 1000) *
1204 /* Max valid TDCO value is 127 */
1206 netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n",
1211 reg_btp |= DBTP_TDC;
1212 m_can_write(cdev, M_CAN_TDCR,
1213 FIELD_PREP(TDCR_TDCO_MASK, tdco));
1216 reg_btp |= FIELD_PREP(DBTP_DBRP_MASK, brp) |
1217 FIELD_PREP(DBTP_DSJW_MASK, sjw) |
1218 FIELD_PREP(DBTP_DTSEG1_MASK, tseg1) |
1219 FIELD_PREP(DBTP_DTSEG2_MASK, tseg2);
1221 m_can_write(cdev, M_CAN_DBTP, reg_btp);
1227 /* Configure M_CAN chip:
1228 * - set rx buffer/fifo element size
1229 * - configure rx fifo
1230 * - accept non-matching frame into fifo 0
1231 * - configure tx buffer
1232 * - >= v3.1.x: TX FIFO is used
1235 * - configure timestamp generation
1237 static void m_can_chip_config(struct net_device *dev)
1239 struct m_can_classdev *cdev = netdev_priv(dev);
1242 m_can_config_endisable(cdev, true);
1244 /* RX Buffer/FIFO Element Size 64 bytes data field */
1245 m_can_write(cdev, M_CAN_RXESC,
1246 FIELD_PREP(RXESC_RBDS_MASK, RXESC_64B) |
1247 FIELD_PREP(RXESC_F1DS_MASK, RXESC_64B) |
1248 FIELD_PREP(RXESC_F0DS_MASK, RXESC_64B));
1250 /* Accept Non-matching Frames Into FIFO 0 */
1251 m_can_write(cdev, M_CAN_GFC, 0x0);
1253 if (cdev->version == 30) {
1254 /* only support one Tx Buffer currently */
1255 m_can_write(cdev, M_CAN_TXBC, FIELD_PREP(TXBC_NDTB_MASK, 1) |
1256 cdev->mcfg[MRAM_TXB].off);
1258 /* TX FIFO is used for newer IP Core versions */
1259 m_can_write(cdev, M_CAN_TXBC,
1260 FIELD_PREP(TXBC_TFQS_MASK,
1261 cdev->mcfg[MRAM_TXB].num) |
1262 cdev->mcfg[MRAM_TXB].off);
1265 /* support 64 bytes payload */
1266 m_can_write(cdev, M_CAN_TXESC,
1267 FIELD_PREP(TXESC_TBDS_MASK, TXESC_TBDS_64B));
1270 if (cdev->version == 30) {
1271 m_can_write(cdev, M_CAN_TXEFC,
1272 FIELD_PREP(TXEFC_EFS_MASK, 1) |
1273 cdev->mcfg[MRAM_TXE].off);
1275 /* Full TX Event FIFO is used */
1276 m_can_write(cdev, M_CAN_TXEFC,
1277 FIELD_PREP(TXEFC_EFS_MASK,
1278 cdev->mcfg[MRAM_TXE].num) |
1279 cdev->mcfg[MRAM_TXE].off);
1282 /* rx fifo configuration, blocking mode, fifo size 1 */
1283 m_can_write(cdev, M_CAN_RXF0C,
1284 FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF0].num) |
1285 cdev->mcfg[MRAM_RXF0].off);
1287 m_can_write(cdev, M_CAN_RXF1C,
1288 FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF1].num) |
1289 cdev->mcfg[MRAM_RXF1].off);
1291 cccr = m_can_read(cdev, M_CAN_CCCR);
1292 test = m_can_read(cdev, M_CAN_TEST);
1294 if (cdev->version == 30) {
1297 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_DAR |
1298 FIELD_PREP(CCCR_CMR_MASK, FIELD_MAX(CCCR_CMR_MASK)) |
1299 FIELD_PREP(CCCR_CME_MASK, FIELD_MAX(CCCR_CME_MASK)));
1301 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1302 cccr |= FIELD_PREP(CCCR_CME_MASK, CCCR_CME_CANFD_BRS);
1305 /* Version 3.1.x or 3.2.x */
1306 cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE |
1307 CCCR_NISO | CCCR_DAR);
1309 /* Only 3.2.x has NISO Bit implemented */
1310 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
1313 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD)
1314 cccr |= (CCCR_BRSE | CCCR_FDOE);
1318 if (cdev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1319 cccr |= CCCR_TEST | CCCR_MON;
1323 /* Enable Monitoring (all versions) */
1324 if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1327 /* Disable Auto Retransmission (all versions) */
1328 if (cdev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
1332 m_can_write(cdev, M_CAN_CCCR, cccr);
1333 m_can_write(cdev, M_CAN_TEST, test);
1335 /* Enable interrupts */
1336 m_can_write(cdev, M_CAN_IR, IR_ALL_INT);
1337 if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1338 if (cdev->version == 30)
1339 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1342 m_can_write(cdev, M_CAN_IE, IR_ALL_INT &
1345 m_can_write(cdev, M_CAN_IE, IR_ALL_INT);
1347 /* route all interrupts to INT0 */
1348 m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0);
1350 /* set bittiming params */
1351 m_can_set_bittiming(dev);
1353 /* enable internal timestamp generation, with a prescaler of 16. The
1354 * prescaler is applied to the nominal bit timing
1356 m_can_write(cdev, M_CAN_TSCC,
1357 FIELD_PREP(TSCC_TCP_MASK, 0xf) |
1358 FIELD_PREP(TSCC_TSS_MASK, TSCC_TSS_INTERNAL));
1360 m_can_config_endisable(cdev, false);
1362 if (cdev->ops->init)
1363 cdev->ops->init(cdev);
1366 static void m_can_start(struct net_device *dev)
1368 struct m_can_classdev *cdev = netdev_priv(dev);
1370 /* basic m_can configuration */
1371 m_can_chip_config(dev);
1373 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
1375 m_can_enable_all_interrupts(cdev);
1378 static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
1381 case CAN_MODE_START:
1384 netif_wake_queue(dev);
1393 /* Checks core release number of M_CAN
1394 * returns 0 if an unsupported device is detected
1395 * else it returns the release and step coded as:
1396 * return value = 10 * <release> + 1 * <step>
1398 static int m_can_check_core_release(struct m_can_classdev *cdev)
1405 /* Read Core Release Version and split into version number
1406 * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1;
1408 crel_reg = m_can_read(cdev, M_CAN_CREL);
1409 rel = (u8)FIELD_GET(CREL_REL_MASK, crel_reg);
1410 step = (u8)FIELD_GET(CREL_STEP_MASK, crel_reg);
1413 /* M_CAN v3.x.y: create return value */
1416 /* Unsupported M_CAN version */
1423 /* Selectable Non ISO support only in version 3.2.x
1424 * This function checks if the bit is writable.
1426 static bool m_can_niso_supported(struct m_can_classdev *cdev)
1428 u32 cccr_reg, cccr_poll = 0;
1429 int niso_timeout = -ETIMEDOUT;
1432 m_can_config_endisable(cdev, true);
1433 cccr_reg = m_can_read(cdev, M_CAN_CCCR);
1434 cccr_reg |= CCCR_NISO;
1435 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1437 for (i = 0; i <= 10; i++) {
1438 cccr_poll = m_can_read(cdev, M_CAN_CCCR);
1439 if (cccr_poll == cccr_reg) {
1448 cccr_reg &= ~(CCCR_NISO);
1449 m_can_write(cdev, M_CAN_CCCR, cccr_reg);
1451 m_can_config_endisable(cdev, false);
1453 /* return false if time out (-ETIMEDOUT), else return true */
1454 return !niso_timeout;
1457 static int m_can_dev_setup(struct m_can_classdev *cdev)
1459 struct net_device *dev = cdev->net;
1460 int m_can_version, err;
1462 m_can_version = m_can_check_core_release(cdev);
1463 /* return if unsupported version */
1464 if (!m_can_version) {
1465 dev_err(cdev->dev, "Unsupported version number: %2d",
1470 if (!cdev->is_peripheral)
1471 netif_napi_add(dev, &cdev->napi, m_can_poll);
1473 /* Shared properties of all M_CAN versions */
1474 cdev->version = m_can_version;
1475 cdev->can.do_set_mode = m_can_set_mode;
1476 cdev->can.do_get_berr_counter = m_can_get_berr_counter;
1478 /* Set M_CAN supported operations */
1479 cdev->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1480 CAN_CTRLMODE_LISTENONLY |
1481 CAN_CTRLMODE_BERR_REPORTING |
1483 CAN_CTRLMODE_ONE_SHOT;
1485 /* Set properties depending on M_CAN version */
1486 switch (cdev->version) {
1488 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */
1489 err = can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1492 cdev->can.bittiming_const = &m_can_bittiming_const_30X;
1493 cdev->can.data_bittiming_const = &m_can_data_bittiming_const_30X;
1496 /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */
1497 err = can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
1500 cdev->can.bittiming_const = &m_can_bittiming_const_31X;
1501 cdev->can.data_bittiming_const = &m_can_data_bittiming_const_31X;
1505 /* Support both MCAN version v3.2.x and v3.3.0 */
1506 cdev->can.bittiming_const = &m_can_bittiming_const_31X;
1507 cdev->can.data_bittiming_const = &m_can_data_bittiming_const_31X;
1509 cdev->can.ctrlmode_supported |=
1510 (m_can_niso_supported(cdev) ?
1511 CAN_CTRLMODE_FD_NON_ISO : 0);
1514 dev_err(cdev->dev, "Unsupported version number: %2d",
1519 if (cdev->ops->init)
1520 cdev->ops->init(cdev);
1525 static void m_can_stop(struct net_device *dev)
1527 struct m_can_classdev *cdev = netdev_priv(dev);
1529 /* disable all interrupts */
1530 m_can_disable_all_interrupts(cdev);
1532 /* Set init mode to disengage from the network */
1533 m_can_config_endisable(cdev, true);
1535 /* set the state as STOPPED */
1536 cdev->can.state = CAN_STATE_STOPPED;
1539 static int m_can_close(struct net_device *dev)
1541 struct m_can_classdev *cdev = netdev_priv(dev);
1543 netif_stop_queue(dev);
1545 if (!cdev->is_peripheral)
1546 napi_disable(&cdev->napi);
1549 m_can_clk_stop(cdev);
1550 free_irq(dev->irq, dev);
1552 if (cdev->is_peripheral) {
1553 cdev->tx_skb = NULL;
1554 destroy_workqueue(cdev->tx_wq);
1558 if (cdev->is_peripheral)
1559 can_rx_offload_disable(&cdev->offload);
1563 phy_power_off(cdev->transceiver);
1568 static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx)
1570 struct m_can_classdev *cdev = netdev_priv(dev);
1571 /*get wrap around for loopback skb index */
1572 unsigned int wrap = cdev->can.echo_skb_max;
1575 /* calculate next index */
1576 next_idx = (++putidx >= wrap ? 0 : putidx);
1578 /* check if occupied */
1579 return !!cdev->can.echo_skb[next_idx];
1582 static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev)
1584 struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data;
1585 struct net_device *dev = cdev->net;
1586 struct sk_buff *skb = cdev->tx_skb;
1587 struct id_and_dlc fifo_header;
1592 cdev->tx_skb = NULL;
1594 /* Generate ID field for TX buffer Element */
1595 /* Common to all supported M_CAN versions */
1596 if (cf->can_id & CAN_EFF_FLAG) {
1597 fifo_header.id = cf->can_id & CAN_EFF_MASK;
1598 fifo_header.id |= TX_BUF_XTD;
1600 fifo_header.id = ((cf->can_id & CAN_SFF_MASK) << 18);
1603 if (cf->can_id & CAN_RTR_FLAG)
1604 fifo_header.id |= TX_BUF_RTR;
1606 if (cdev->version == 30) {
1607 netif_stop_queue(dev);
1609 fifo_header.dlc = can_fd_len2dlc(cf->len) << 16;
1611 /* Write the frame ID, DLC, and payload to the FIFO element. */
1612 err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, &fifo_header, 2);
1616 err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_DATA,
1617 cf->data, DIV_ROUND_UP(cf->len, 4));
1621 if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) {
1622 cccr = m_can_read(cdev, M_CAN_CCCR);
1623 cccr &= ~CCCR_CMR_MASK;
1624 if (can_is_canfd_skb(skb)) {
1625 if (cf->flags & CANFD_BRS)
1626 cccr |= FIELD_PREP(CCCR_CMR_MASK,
1627 CCCR_CMR_CANFD_BRS);
1629 cccr |= FIELD_PREP(CCCR_CMR_MASK,
1632 cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CAN);
1634 m_can_write(cdev, M_CAN_CCCR, cccr);
1636 m_can_write(cdev, M_CAN_TXBTIE, 0x1);
1638 can_put_echo_skb(skb, dev, 0, 0);
1640 m_can_write(cdev, M_CAN_TXBAR, 0x1);
1641 /* End of xmit function for version 3.0.x */
1643 /* Transmit routine for version >= v3.1.x */
1645 /* Check if FIFO full */
1646 if (m_can_tx_fifo_full(cdev)) {
1647 /* This shouldn't happen */
1648 netif_stop_queue(dev);
1650 "TX queue active although FIFO is full.");
1652 if (cdev->is_peripheral) {
1654 dev->stats.tx_dropped++;
1655 return NETDEV_TX_OK;
1657 return NETDEV_TX_BUSY;
1661 /* get put index for frame */
1662 putidx = FIELD_GET(TXFQS_TFQPI_MASK,
1663 m_can_read(cdev, M_CAN_TXFQS));
1665 /* Construct DLC Field, with CAN-FD configuration.
1666 * Use the put index of the fifo as the message marker,
1667 * used in the TX interrupt for sending the correct echo frame.
1670 /* get CAN FD configuration of frame */
1672 if (can_is_canfd_skb(skb)) {
1673 fdflags |= TX_BUF_FDF;
1674 if (cf->flags & CANFD_BRS)
1675 fdflags |= TX_BUF_BRS;
1678 fifo_header.dlc = FIELD_PREP(TX_BUF_MM_MASK, putidx) |
1679 FIELD_PREP(TX_BUF_DLC_MASK, can_fd_len2dlc(cf->len)) |
1680 fdflags | TX_BUF_EFC;
1681 err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, &fifo_header, 2);
1685 err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA,
1686 cf->data, DIV_ROUND_UP(cf->len, 4));
1690 /* Push loopback echo.
1691 * Will be looped back on TX interrupt based on message marker
1693 can_put_echo_skb(skb, dev, putidx, 0);
1695 /* Enable TX FIFO element to start transfer */
1696 m_can_write(cdev, M_CAN_TXBAR, (1 << putidx));
1698 /* stop network queue if fifo full */
1699 if (m_can_tx_fifo_full(cdev) ||
1700 m_can_next_echo_skb_occupied(dev, putidx))
1701 netif_stop_queue(dev);
1704 return NETDEV_TX_OK;
1707 netdev_err(dev, "FIFO write returned %d\n", err);
1708 m_can_disable_all_interrupts(cdev);
1709 return NETDEV_TX_BUSY;
1712 static void m_can_tx_work_queue(struct work_struct *ws)
1714 struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev,
1717 m_can_tx_handler(cdev);
1720 static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
1721 struct net_device *dev)
1723 struct m_can_classdev *cdev = netdev_priv(dev);
1725 if (can_dropped_invalid_skb(dev, skb))
1726 return NETDEV_TX_OK;
1728 if (cdev->is_peripheral) {
1730 netdev_err(dev, "hard_xmit called while tx busy\n");
1731 return NETDEV_TX_BUSY;
1734 if (cdev->can.state == CAN_STATE_BUS_OFF) {
1737 /* Need to stop the queue to avoid numerous requests
1738 * from being sent. Suggested improvement is to create
1739 * a queueing mechanism that will queue the skbs and
1740 * process them in order.
1743 netif_stop_queue(cdev->net);
1744 queue_work(cdev->tx_wq, &cdev->tx_work);
1748 return m_can_tx_handler(cdev);
1751 return NETDEV_TX_OK;
1754 static int m_can_open(struct net_device *dev)
1756 struct m_can_classdev *cdev = netdev_priv(dev);
1759 err = phy_power_on(cdev->transceiver);
1763 err = m_can_clk_start(cdev);
1765 goto out_phy_power_off;
1767 /* open the can device */
1768 err = open_candev(dev);
1770 netdev_err(dev, "failed to open can device\n");
1771 goto exit_disable_clks;
1774 if (cdev->is_peripheral)
1775 can_rx_offload_enable(&cdev->offload);
1777 /* register interrupt handler */
1778 if (cdev->is_peripheral) {
1779 cdev->tx_skb = NULL;
1780 cdev->tx_wq = alloc_workqueue("mcan_wq",
1781 WQ_FREEZABLE | WQ_MEM_RECLAIM, 0);
1787 INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);
1789 err = request_threaded_irq(dev->irq, NULL, m_can_isr,
1793 err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
1798 netdev_err(dev, "failed to request interrupt\n");
1802 /* start the m_can controller */
1805 if (!cdev->is_peripheral)
1806 napi_enable(&cdev->napi);
1808 netif_start_queue(dev);
1813 if (cdev->is_peripheral)
1814 destroy_workqueue(cdev->tx_wq);
1816 if (cdev->is_peripheral)
1817 can_rx_offload_disable(&cdev->offload);
1820 m_can_clk_stop(cdev);
1822 phy_power_off(cdev->transceiver);
1826 static const struct net_device_ops m_can_netdev_ops = {
1827 .ndo_open = m_can_open,
1828 .ndo_stop = m_can_close,
1829 .ndo_start_xmit = m_can_start_xmit,
1830 .ndo_change_mtu = can_change_mtu,
1833 static const struct ethtool_ops m_can_ethtool_ops = {
1834 .get_ts_info = ethtool_op_get_ts_info,
1837 static int register_m_can_dev(struct net_device *dev)
1839 dev->flags |= IFF_ECHO; /* we support local echo */
1840 dev->netdev_ops = &m_can_netdev_ops;
1841 dev->ethtool_ops = &m_can_ethtool_ops;
1843 return register_candev(dev);
1846 static void m_can_of_parse_mram(struct m_can_classdev *cdev,
1847 const u32 *mram_config_vals)
1849 cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0];
1850 cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1];
1851 cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off +
1852 cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
1853 cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2];
1854 cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off +
1855 cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
1856 cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] &
1857 FIELD_MAX(RXFC_FS_MASK);
1858 cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off +
1859 cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
1860 cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] &
1861 FIELD_MAX(RXFC_FS_MASK);
1862 cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off +
1863 cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
1864 cdev->mcfg[MRAM_RXB].num = mram_config_vals[5];
1865 cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off +
1866 cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
1867 cdev->mcfg[MRAM_TXE].num = mram_config_vals[6];
1868 cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off +
1869 cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
1870 cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] &
1871 FIELD_MAX(TXBC_NDTB_MASK);
1874 "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",
1875 cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num,
1876 cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num,
1877 cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num,
1878 cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num,
1879 cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num,
1880 cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num,
1881 cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num);
1884 int m_can_init_ram(struct m_can_classdev *cdev)
1889 /* initialize the entire Message RAM in use to avoid possible
1890 * ECC/parity checksum errors when reading an uninitialized buffer
1892 start = cdev->mcfg[MRAM_SIDF].off;
1893 end = cdev->mcfg[MRAM_TXB].off +
1894 cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;
1896 for (i = start; i < end; i += 4) {
1897 err = m_can_fifo_write_no_off(cdev, i, 0x0);
1904 EXPORT_SYMBOL_GPL(m_can_init_ram);
1906 int m_can_class_get_clocks(struct m_can_classdev *cdev)
1910 cdev->hclk = devm_clk_get(cdev->dev, "hclk");
1911 cdev->cclk = devm_clk_get(cdev->dev, "cclk");
1913 if (IS_ERR(cdev->cclk)) {
1914 dev_err(cdev->dev, "no clock found\n");
1920 EXPORT_SYMBOL_GPL(m_can_class_get_clocks);
1922 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
1925 struct m_can_classdev *class_dev = NULL;
1926 u32 mram_config_vals[MRAM_CFG_LEN];
1927 struct net_device *net_dev;
1931 ret = fwnode_property_read_u32_array(dev_fwnode(dev),
1934 sizeof(mram_config_vals) / 4);
1936 dev_err(dev, "Could not get Message RAM configuration.");
1941 * Defines the total amount of echo buffers for loopback
1943 tx_fifo_size = mram_config_vals[7];
1945 /* allocate the m_can device */
1946 net_dev = alloc_candev(sizeof_priv, tx_fifo_size);
1948 dev_err(dev, "Failed to allocate CAN device");
1952 class_dev = netdev_priv(net_dev);
1953 class_dev->net = net_dev;
1954 class_dev->dev = dev;
1955 SET_NETDEV_DEV(net_dev, dev);
1957 m_can_of_parse_mram(class_dev, mram_config_vals);
1961 EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);
1963 void m_can_class_free_dev(struct net_device *net)
1967 EXPORT_SYMBOL_GPL(m_can_class_free_dev);
1969 int m_can_class_register(struct m_can_classdev *cdev)
1973 if (cdev->pm_clock_support) {
1974 ret = m_can_clk_start(cdev);
1979 if (cdev->is_peripheral) {
1980 ret = can_rx_offload_add_manual(cdev->net, &cdev->offload,
1986 ret = m_can_dev_setup(cdev);
1988 goto rx_offload_del;
1990 ret = register_m_can_dev(cdev->net);
1992 dev_err(cdev->dev, "registering %s failed (err=%d)\n",
1993 cdev->net->name, ret);
1994 goto rx_offload_del;
1997 of_can_transceiver(cdev->net);
1999 dev_info(cdev->dev, "%s device registered (irq=%d, version=%d)\n",
2000 KBUILD_MODNAME, cdev->net->irq, cdev->version);
2003 * Stop clocks. They will be reactivated once the M_CAN device is opened
2005 m_can_clk_stop(cdev);
2010 if (cdev->is_peripheral)
2011 can_rx_offload_del(&cdev->offload);
2013 m_can_clk_stop(cdev);
2017 EXPORT_SYMBOL_GPL(m_can_class_register);
2019 void m_can_class_unregister(struct m_can_classdev *cdev)
2021 if (cdev->is_peripheral)
2022 can_rx_offload_del(&cdev->offload);
2023 unregister_candev(cdev->net);
2025 EXPORT_SYMBOL_GPL(m_can_class_unregister);
2027 int m_can_class_suspend(struct device *dev)
2029 struct m_can_classdev *cdev = dev_get_drvdata(dev);
2030 struct net_device *ndev = cdev->net;
2032 if (netif_running(ndev)) {
2033 netif_stop_queue(ndev);
2034 netif_device_detach(ndev);
2036 m_can_clk_stop(cdev);
2039 pinctrl_pm_select_sleep_state(dev);
2041 cdev->can.state = CAN_STATE_SLEEPING;
2045 EXPORT_SYMBOL_GPL(m_can_class_suspend);
2047 int m_can_class_resume(struct device *dev)
2049 struct m_can_classdev *cdev = dev_get_drvdata(dev);
2050 struct net_device *ndev = cdev->net;
2052 pinctrl_pm_select_default_state(dev);
2054 cdev->can.state = CAN_STATE_ERROR_ACTIVE;
2056 if (netif_running(ndev)) {
2059 ret = m_can_clk_start(cdev);
2063 m_can_init_ram(cdev);
2065 netif_device_attach(ndev);
2066 netif_start_queue(ndev);
2071 EXPORT_SYMBOL_GPL(m_can_class_resume);
2073 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
2074 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
2075 MODULE_LICENSE("GPL v2");
2076 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");