1 /* Xilinx CAN device driver
3 * Copyright (C) 2012 - 2014 Xilinx, Inc.
4 * Copyright (C) 2009 PetaLogix. All rights reserved.
7 * This driver is developed for Axi CAN IP and for Zynq CANPS Controller.
8 * This program is free software: you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation, either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
19 #include <linux/clk.h>
20 #include <linux/errno.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/netdevice.h>
28 #include <linux/platform_device.h>
29 #include <linux/skbuff.h>
30 #include <linux/string.h>
31 #include <linux/types.h>
32 #include <linux/can/dev.h>
33 #include <linux/can/error.h>
34 #include <linux/can/led.h>
35 #include <linux/pm_runtime.h>
36 #include <linux/of_device.h>
38 #define DRIVER_NAME "xilinx_can"
40 /* CAN registers set */
42 XCAN_SRR_OFFSET = 0x00, /* Software reset */
43 XCAN_MSR_OFFSET = 0x04, /* Mode select */
44 XCAN_BRPR_OFFSET = 0x08, /* Baud rate prescaler */
45 XCAN_BTR_OFFSET = 0x0C, /* Bit timing */
46 XCAN_ECR_OFFSET = 0x10, /* Error counter */
47 XCAN_ESR_OFFSET = 0x14, /* Error status */
48 XCAN_SR_OFFSET = 0x18, /* Status */
49 XCAN_ISR_OFFSET = 0x1C, /* Interrupt status */
50 XCAN_IER_OFFSET = 0x20, /* Interrupt enable */
51 XCAN_ICR_OFFSET = 0x24, /* Interrupt clear */
52 XCAN_TXFIFO_ID_OFFSET = 0x30,/* TX FIFO ID */
53 XCAN_TXFIFO_DLC_OFFSET = 0x34, /* TX FIFO DLC */
54 XCAN_TXFIFO_DW1_OFFSET = 0x38, /* TX FIFO Data Word 1 */
55 XCAN_TXFIFO_DW2_OFFSET = 0x3C, /* TX FIFO Data Word 2 */
56 XCAN_RXFIFO_ID_OFFSET = 0x50, /* RX FIFO ID */
57 XCAN_RXFIFO_DLC_OFFSET = 0x54, /* RX FIFO DLC */
58 XCAN_RXFIFO_DW1_OFFSET = 0x58, /* RX FIFO Data Word 1 */
59 XCAN_RXFIFO_DW2_OFFSET = 0x5C, /* RX FIFO Data Word 2 */
60 XCAN_F_BRPR_OFFSET = 0x088, /* Data Phase Buad Rate
63 XCAN_F_BTR_OFFSET = 0x08C, /* Data Phase Bit Timing */
64 XCAN_TRR_OFFSET = 0x090, /* Tx Buffer Ready Request */
65 XCAN_IETRS_OFFSET = 0x094, /* TRR Served Interrupt
68 XCANFD_TXFIFO_ID_OFFSET = 0x0100, /* Tx Message Buffer Element
71 XCANFD_TXFIFO_DLC_OFFSET = 0x0104, /* Tx Message Buffer Element
74 XCANFD_TXFIFO_DW_OFFSET = 0x0108, /* Tx Message Buffer Element
77 XCANFD_RXFIFO_ID_OFFSET = 0x1100, /* Rx Message Buffer Element
80 XCANFD_RXFIFO_DLC_OFFSET = 0x1104, /* Rx Message Buffer Element
83 XCANFD_RXFIFO_DW_OFFSET = 0x1108, /* Rx Message Buffer Element
86 XCAN_AFMR_BASE_OFFSET = 0x1A00, /* Acceptance Filter */
87 XCAN_AFIDR_BASE_OFFSET = 0x1A04, /* Acceptance Filter ID */
88 XCAN_AFR_OFFSET = 0x0E0, /* Acceptance Filter */
89 XCAN_FSR_OFFSET = 0x0E8, /* Receive FIFO Status */
90 XCAN_TIMESTAMPR_OFFSET = 0x0028, /* Time Stamp */
93 /* CAN register bit masks - XCAN_<REG>_<BIT>_MASK */
94 #define XCAN_SRR_CEN_MASK 0x00000002 /* CAN enable */
95 #define XCAN_SRR_RESET_MASK 0x00000001 /* Soft Reset the CAN core */
96 #define XCAN_MSR_LBACK_MASK 0x00000002 /* Loop back mode select */
97 #define XCAN_MSR_SLEEP_MASK 0x00000001 /* Sleep mode select */
98 #define XCAN_BRPR_BRP_MASK 0x000000FF /* Baud rate prescaler */
99 #define XCAN_BTR_SJW_MASK 0x00000180 /* Synchronous jump width */
100 #define XCAN_BTR_TS2_MASK 0x00000070 /* Time segment 2 */
101 #define XCAN_BTR_TS1_MASK 0x0000000F /* Time segment 1 */
102 #define XCANFD_BTR_SJW_MASK 0x000F0000 /* Sync Jump Width */
103 #define XCANFD_BTR_TS2_MASK 0x00000F00 /* Time Segment 2 */
104 #define XCANFD_BTR_TS1_MASK 0x0000003F /* Time Segment 1 */
105 #define XCAN_ECR_REC_MASK 0x0000FF00 /* Receive error counter */
106 #define XCAN_ECR_TEC_MASK 0x000000FF /* Transmit error counter */
107 #define XCAN_ESR_ACKER_MASK 0x00000010 /* ACK error */
108 #define XCAN_ESR_BERR_MASK 0x00000008 /* Bit error */
109 #define XCAN_ESR_STER_MASK 0x00000004 /* Stuff error */
110 #define XCAN_ESR_FMER_MASK 0x00000002 /* Form error */
111 #define XCAN_ESR_CRCER_MASK 0x00000001 /* CRC error */
112 #define XCAN_SR_TXFLL_MASK 0x00000400 /* TX FIFO is full */
113 #define XCAN_SR_ESTAT_MASK 0x00000180 /* Error status */
114 #define XCAN_SR_ERRWRN_MASK 0x00000040 /* Error warning */
115 #define XCAN_SR_NORMAL_MASK 0x00000008 /* Normal mode */
116 #define XCAN_SR_LBACK_MASK 0x00000002 /* Loop back mode */
117 #define XCAN_SR_CONFIG_MASK 0x00000001 /* Configuration mode */
118 #define XCAN_IXR_TXFEMP_MASK 0x00004000 /* TX FIFO Empty */
119 #define XCAN_IXR_WKUP_MASK 0x00000800 /* Wake up interrupt */
120 #define XCAN_IXR_SLP_MASK 0x00000400 /* Sleep interrupt */
121 #define XCAN_IXR_BSOFF_MASK 0x00000200 /* Bus off interrupt */
122 #define XCAN_IXR_ERROR_MASK 0x00000100 /* Error interrupt */
123 #define XCAN_IXR_RXNEMP_MASK 0x00000080 /* RX FIFO NotEmpty intr */
124 #define XCAN_IXR_RXOFLW_MASK 0x00000040 /* RX FIFO Overflow intr */
125 #define XCAN_IXR_RXOK_MASK 0x00000010 /* Message received intr */
126 #define XCAN_IXR_TXFLL_MASK 0x00000004 /* Tx FIFO Full intr */
127 #define XCAN_IXR_TXOK_MASK 0x00000002 /* TX successful intr */
128 #define XCAN_IXR_ARBLST_MASK 0x00000001 /* Arbitration lost intr */
129 #define XCAN_IDR_ID1_MASK 0xFFE00000 /* Standard msg identifier */
130 #define XCAN_IDR_SRR_MASK 0x00100000 /* Substitute remote TXreq */
131 #define XCAN_IDR_IDE_MASK 0x00080000 /* Identifier extension */
132 #define XCAN_IDR_ID2_MASK 0x0007FFFE /* Extended message ident */
133 #define XCAN_IDR_RTR_MASK 0x00000001 /* Remote TX request */
134 #define XCAN_DLCR_DLC_MASK 0xF0000000 /* Data length code */
135 #define XCAN_MSR_BRSD_MASK 0x00000008 /* Bit Rate Switch Select */
136 #define XCAN_MSR_SNOOP_MASK 0x00000004 /* Snoop Mode Select */
137 #define XCAN_MSR_DPEE_MASK 0x00000020 /* Protocol Exception
140 #define XCAN_MSR_SBR_MASK 0x00000040 /* Start Bus-Off Recovery */
141 #define XCAN_MSR_ABR_MASK 0x00000080 /* Auto Bus-Off Recovery */
142 #define XCAN_MSR_CONFIG_MASK 0x000000F8 /* Configuration Mode */
143 #define XCAN_F_BRPR_TDCMASK 0x00001F00 /* TDC Value */
144 #define XCAN_F_BTR_SJW_MASK 0x00070000 /* Sync Jump Width */
145 #define XCAN_F_BTR_TS2_MASK 0x00000700 /* Time Segment 2 */
146 #define XCAN_F_BTR_TS1_MASK 0x0000000F /* Time Segment 1 */
147 #define XCAN_ESR_F_BERR_MASK 0x00000800 /* F_Bit Error */
148 #define XCAN_ESR_F_STER_MASK 0x00000400 /* F_Stuff Error */
149 #define XCAN_ESR_F_FMER_MASK 0x00000200 /* F_Form Error */
150 #define XCAN_ESR_F_CRCER_MASK 0x00000100 /* F_CRC Error */
151 #define XCAN_SR_SNOOP_MASK 0x00001000 /* Snoop Mode */
152 #define XCAN_SR_BBSY_MASK 0x00000020 /* Bus Busy */
153 #define XCAN_SR_BIDLE_MASK 0x00000010 /* Bus Idle */
154 #define XCAN_SR_SLEEP_MASK 0x00000004 /* Sleep Mode */
155 #define XCAN_SR_PEE_CONFIG_MASK 0x00000200 /* Protocol Exception
158 #define XCAN_SR_BSFR_CONFIG_MASK 0x00000400 /* Bus-Off recovery
161 #define XCAN_SR_NISO_MASK 0x00000800 /* Non-ISO Core */
162 #define XCAN_FSR_FL_MASK 0x00003F00 /* Fill Level */
163 #define XCAN_FSR_RI_MASK 0x0000001F /* Read Index */
164 #define XCAN_FSR_IRI_MASK 0x00000080 /* Increment Read Index */
165 #define XCAN_IXR_RXMNF_MASK 0x00020000 /* Rx Match Not Finished Intr */
166 #define XCAN_IXR_TXRRS_MASK 0x00002000 /* Tx Buffer Ready Request Served
169 #define XCAN_IXR_PEE_MASK 0x00000004 /* Protocol Exception Intr */
170 #define XCAN_IXR_BSRD_MASK 0x00000008 /* Bus-Off recovery done Intr */
171 #define XCAN_AFR_ENABLE_ALL 0xFFFFFFFF /* All filter Enable */
172 #define XCAN_DLCR_EDL_MASK 0x08000000 /* EDL Mask in DLC */
173 #define XCAN_DLCR_BRS_MASK 0x04000000 /* BRS Mask in DLC */
174 #define XCAN_DLCR_DLC_SHIFT 28 /* BRS Mask in DLC */
175 #define XCAN_DLCR_EDL_SHIFT 27 /* EDL Mask in DLC */
176 #define XCAN_DLCR_BRS_SHIFT 26
178 #define XCAN_INTR_ALL (XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
179 XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
180 XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | \
181 XCAN_IXR_ARBLST_MASK)
183 /* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
184 #define XCAN_BTR_SJW_SHIFT 7 /* Synchronous jump width */
185 #define XCAN_BTR_TS2_SHIFT 4 /* Time segment 2 */
186 #define XCANFD_BTR_SJW_SHIFT 16 /* Sync Jump Width Shift */
187 #define XCANFD_BTR_TS2_SHIFT 8 /* Time Segment 2 Shift */
188 #define XCAN_SR_ESTAT_SHIFT 7 /* Error Status Shift */
189 #define XCAN_RXLRM_BI_SHIFT 18 /* Rx Buffer Index Shift Value */
190 #define XCAN_CSB_SHIFT 16 /* Core Status Bit Shift Value */
191 #define XCAN_IDR_SRR_SHIFT 20 /* Soft Reset Shift */
192 #define XCAN_IDR_IDE_SHIFT 19 /* Identifier Extension Shift */
193 #define XCAN_IDR_ID1_SHIFT 21 /* Standard Messg Identifier */
194 #define XCAN_IDR_ID2_SHIFT 1 /* Extended Message Identifier */
195 #define XCAN_DLCR_DLC_SHIFT 28 /* Data length code */
196 #define XCAN_ESR_REC_SHIFT 8 /* Rx Error Count */
198 /* CAN frame length constants */
199 #define XCAN_FRAME_MAX_DATA_LEN 8
200 #define XCAN_TIMEOUT (1 * HZ)
201 #define XCANFD_MAX_FRAME_LEN 72
202 #define XCANFD_FRAME_MAX_DATA_LEN 64
203 #define XCANFD_DW_BYTES 4
204 #define XCANFD_CTRLREG_WIDTH 4
207 #define CANFD_SUPPORT BIT(0)
209 /* CANFD Tx and Rx Ram offsets */
210 #define XCANFD_TXDW_OFFSET(n) (XCANFD_TXFIFO_DW_OFFSET + ((n) * \
211 XCANFD_MAX_FRAME_LEN))
212 #define XCANFD_TXID_OFFSET(n) (XCANFD_TXFIFO_ID_OFFSET + ((n) * \
213 XCANFD_MAX_FRAME_LEN))
214 #define XCANFD_TXDLC_OFFSET(n) (XCANFD_TXFIFO_DLC_OFFSET + ((n) *\
215 XCANFD_MAX_FRAME_LEN))
216 #define XCANFD_RXDLC_OFFSET(readindex) (XCANFD_RXFIFO_DLC_OFFSET + \
217 ((readindex) * XCANFD_MAX_FRAME_LEN))
218 #define XCANFD_RXID_OFFSET(readindex) (XCANFD_RXFIFO_ID_OFFSET + \
219 ((readindex) * XCANFD_MAX_FRAME_LEN))
220 #define XCANFD_RXDW_OFFSET(readindex) (XCANFD_RXFIFO_DW_OFFSET + \
221 ((readindex) * XCANFD_MAX_FRAME_LEN))
224 * struct xcan_priv - This definition define CAN driver instance
225 * @can: CAN private data structure.
226 * @tx_head: Tx CAN packets ready to send on the queue
227 * @tx_tail: Tx CAN packets successfully sended on the queue
228 * @tx_max: Maximum number packets the driver can send
229 * @napi: NAPI structure
230 * @read_reg: For reading data from CAN registers
231 * @write_reg: For writing data to CAN registers
232 * @dev: Network device data structure
233 * @reg_base: Ioremapped address to registers
234 * @irq_flags: For request_irq()
235 * @bus_clk: Pointer to struct clk
236 * @can_clk: Pointer to struct clk
237 * @quirks: Needed for different IP cores
241 unsigned int tx_head;
242 unsigned int tx_tail;
244 struct napi_struct napi;
245 u32 (*read_reg)(const struct xcan_priv *priv, enum xcan_reg reg);
246 void (*write_reg)(const struct xcan_priv *priv, enum xcan_reg reg,
249 void __iomem *reg_base;
250 unsigned long irq_flags;
256 struct xcan_platform_data {
260 /* CAN Bittiming constants as per Xilinx CAN specs */
261 static struct can_bittiming_const xcan_bittiming_const = {
273 /* CAN Data Bittiming constants as per Xilinx CAN specs */
274 static struct can_bittiming_const xcan_data_bittiming_const = {
287 * xcan_write_reg_le - Write a value to the device register little endian
288 * @priv: Driver private data structure
289 * @reg: Register offset
290 * @val: Value to write at the Register offset
292 * Write data to the paricular CAN register
294 static void xcan_write_reg_le(const struct xcan_priv *priv, enum xcan_reg reg,
297 iowrite32(val, priv->reg_base + reg);
301 * xcan_read_reg_le - Read a value from the device register little endian
302 * @priv: Driver private data structure
303 * @reg: Register offset
305 * Read data from the particular CAN register
306 * Return: value read from the CAN register
308 static u32 xcan_read_reg_le(const struct xcan_priv *priv, enum xcan_reg reg)
310 return ioread32(priv->reg_base + reg);
314 * xcan_write_reg_be - Write a value to the device register big endian
315 * @priv: Driver private data structure
316 * @reg: Register offset
317 * @val: Value to write at the Register offset
319 * Write data to the paricular CAN register
321 static void xcan_write_reg_be(const struct xcan_priv *priv, enum xcan_reg reg,
324 iowrite32be(val, priv->reg_base + reg);
328 * xcan_read_reg_be - Read a value from the device register big endian
329 * @priv: Driver private data structure
330 * @reg: Register offset
332 * Read data from the particular CAN register
333 * Return: value read from the CAN register
335 static u32 xcan_read_reg_be(const struct xcan_priv *priv, enum xcan_reg reg)
337 return ioread32be(priv->reg_base + reg);
341 * set_reset_mode - Resets the CAN device mode
342 * @ndev: Pointer to net_device structure
344 * This is the driver reset mode routine.The driver
345 * enters into configuration mode.
347 * Return: 0 on success and failure value on error
349 static int set_reset_mode(struct net_device *ndev)
351 struct xcan_priv *priv = netdev_priv(ndev);
352 unsigned long timeout;
354 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
356 timeout = jiffies + XCAN_TIMEOUT;
357 while (!(priv->read_reg(priv, XCAN_SR_OFFSET) & XCAN_SR_CONFIG_MASK)) {
358 if (time_after(jiffies, timeout)) {
359 netdev_warn(ndev, "timed out for config mode\n");
362 usleep_range(500, 10000);
369 * xcan_set_bittiming - CAN set bit timing routine
370 * @ndev: Pointer to net_device structure
372 * This is the driver set bittiming routine.
373 * Return: 0 on success and failure value on error
375 static int xcan_set_bittiming(struct net_device *ndev)
377 struct xcan_priv *priv = netdev_priv(ndev);
378 struct can_bittiming *bt = &priv->can.bittiming;
379 struct can_bittiming *dbt = &priv->can.data_bittiming;
383 /* Check whether Xilinx CAN is in configuration mode.
384 * It cannot set bit timing if Xilinx CAN is not in configuration mode.
386 is_config_mode = priv->read_reg(priv, XCAN_SR_OFFSET) &
388 if (!is_config_mode) {
390 "BUG! Cannot set bittiming - CAN is not in config mode\n");
394 /* Setting Baud Rate prescalar value in BRPR Register */
395 btr0 = (bt->brp - 1);
397 /* Setting Time Segment 1 in BTR Register */
398 btr1 = (bt->prop_seg + bt->phase_seg1 - 1);
400 /* Setting Time Segment 2 in BTR Register */
401 btr1 |= (bt->phase_seg2 - 1) << ((priv->quirks & CANFD_SUPPORT) ?
402 XCANFD_BTR_TS2_SHIFT : XCAN_BTR_TS2_SHIFT);
404 /* Setting Synchronous jump width in BTR Register */
405 btr1 |= (bt->sjw - 1) << ((priv->quirks & CANFD_SUPPORT) ?
406 XCANFD_BTR_SJW_SHIFT : XCAN_BTR_SJW_SHIFT);
408 priv->write_reg(priv, XCAN_BRPR_OFFSET, btr0);
409 priv->write_reg(priv, XCAN_BTR_OFFSET, btr1);
411 netdev_dbg(ndev, "BRPR=0x%08x, BTR=0x%08x\n",
412 priv->read_reg(priv, XCAN_BRPR_OFFSET),
413 priv->read_reg(priv, XCAN_BTR_OFFSET));
415 if (priv->quirks & CANFD_SUPPORT) {
416 /* Setting Baud Rate prescalar value in F_BRPR Register */
419 /* Setting Time Segment 1 in BTR Register */
420 btr1 = dbt->prop_seg + bt->phase_seg1 - 1;
422 /* Setting Time Segment 2 in BTR Register */
423 btr1 |= (dbt->phase_seg2 - 1) << XCAN_BTR_TS2_SHIFT;
425 /* Setting Synchronous jump width in BTR Register */
426 btr1 |= (dbt->sjw - 1) << XCAN_BTR_SJW_SHIFT;
428 priv->write_reg(priv, XCAN_F_BRPR_OFFSET, btr0);
429 priv->write_reg(priv, XCAN_F_BTR_OFFSET, btr1);
431 netdev_dbg(ndev, "F_BRPR=0x%08x, F_BTR=0x%08x\n",
432 priv->read_reg(priv, XCAN_F_BRPR_OFFSET),
433 priv->read_reg(priv, XCAN_F_BTR_OFFSET));
439 * xcan_chip_start - This the drivers start routine
440 * @ndev: Pointer to net_device structure
442 * This is the drivers start routine.
443 * Based on the State of the CAN device it puts
444 * the CAN device into a proper mode.
446 * Return: 0 on success and failure value on error
448 static int xcan_chip_start(struct net_device *ndev)
450 struct xcan_priv *priv = netdev_priv(ndev);
451 u32 reg_msr, reg_sr_mask, intr_all = 0;
453 unsigned long timeout;
455 /* Check if it is in reset mode */
456 err = set_reset_mode(ndev);
460 err = xcan_set_bittiming(ndev);
464 /* Enable interrupts */
465 if (priv->quirks & CANFD_SUPPORT) {
466 intr_all = XCAN_INTR_ALL | XCAN_IXR_PEE_MASK |
467 XCAN_IXR_BSRD_MASK | XCAN_IXR_RXMNF_MASK |
468 XCAN_IXR_TXRRS_MASK | XCAN_IXR_RXOK_MASK;
470 intr_all = XCAN_INTR_ALL | XCAN_IXR_RXNEMP_MASK;
473 priv->write_reg(priv, XCAN_IER_OFFSET, intr_all);
475 /* Check whether it is loopback mode or normal mode */
476 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
477 reg_msr = XCAN_MSR_LBACK_MASK;
478 reg_sr_mask = XCAN_SR_LBACK_MASK;
481 reg_sr_mask = XCAN_SR_NORMAL_MASK;
484 if (priv->quirks & CANFD_SUPPORT) {
485 /* As per Xilinx canfd spec, default filter enabling is
488 priv->write_reg(priv, XCAN_AFR_OFFSET, XCAN_AFR_ENABLE_ALL);
490 priv->write_reg(priv, XCAN_MSR_OFFSET, reg_msr);
491 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK);
493 timeout = jiffies + XCAN_TIMEOUT;
494 while (!(priv->read_reg(priv, XCAN_SR_OFFSET) & reg_sr_mask)) {
495 if (time_after(jiffies, timeout)) {
497 "timed out for correct mode\n");
501 netdev_dbg(ndev, "status:#x%08x\n",
502 priv->read_reg(priv, XCAN_SR_OFFSET));
504 priv->can.state = CAN_STATE_ERROR_ACTIVE;
512 * xcan_do_set_mode - This sets the mode of the driver
513 * @ndev: Pointer to net_device structure
514 * @mode: Tells the mode of the driver
516 * This check the drivers state and calls the
517 * the corresponding modes to set.
519 * Return: 0 on success and failure value on error
521 static int xcan_do_set_mode(struct net_device *ndev, enum can_mode mode)
527 ret = xcan_chip_start(ndev);
529 netdev_err(ndev, "xcan_chip_start failed!\n");
532 netif_wake_queue(ndev);
543 * xcan_get_freebuffer - Checks free buffer in the configured buffers
544 * @priv: Driver private data structure
546 * While sending data, need to find free buffer from the tx
547 * buffers avialable and then write data to that buffer.
549 * Return: Free Buffer on success and -1 if no buffer available
551 static int xcan_get_freebuffer(struct xcan_priv *priv)
553 u32 bufindex = 0, trrregval = 0;
555 trrregval = priv->read_reg(priv, XCAN_TRR_OFFSET);
556 for (bufindex = 0; bufindex < priv->tx_max; bufindex++) {
557 if (trrregval & (1 << bufindex))
565 * xcan_start_xmit - Starts the transmission
566 * @skb: sk_buff pointer that contains data to be Txed
567 * @ndev: Pointer to net_device structure
569 * This function is invoked from upper layers to initiate transmission. This
570 * function uses the next available free txbuff and populates their fields to
571 * start the transmission.
573 * Return: 0 on success and failure value on error
575 static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
577 struct xcan_priv *priv = netdev_priv(ndev);
578 struct net_device_stats *stats = &ndev->stats;
579 struct canfd_frame *cf = (struct canfd_frame *)skb->data;
580 u32 id, dlc, data[2] = {0, 0};
581 u32 buffnr, ramoff, dwindex = 0, i, trrval;
583 if (can_dropped_invalid_skb(ndev, skb))
586 if (!(priv->quirks & CANFD_SUPPORT)) {
587 /* Check if the TX buffer is full */
588 if (unlikely(priv->read_reg(priv, XCAN_SR_OFFSET) &
589 XCAN_SR_TXFLL_MASK)) {
590 netif_stop_queue(ndev);
591 netdev_err(ndev, "BUG!, TX FIFO full when queue awake!\n");
592 return NETDEV_TX_BUSY;
596 /* Watch carefully on the bit sequence */
597 if (cf->can_id & CAN_EFF_FLAG) {
598 /* Extended CAN ID format */
599 id = ((cf->can_id & CAN_EFF_MASK) << XCAN_IDR_ID2_SHIFT) &
601 id |= (((cf->can_id & CAN_EFF_MASK) >>
602 (CAN_EFF_ID_BITS - CAN_SFF_ID_BITS)) <<
603 XCAN_IDR_ID1_SHIFT) & XCAN_IDR_ID1_MASK;
605 /* The substibute remote TX request bit should be "1"
606 * for extended frames as in the Xilinx CAN datasheet
608 id |= XCAN_IDR_IDE_MASK | XCAN_IDR_SRR_MASK;
610 if (cf->can_id & CAN_RTR_FLAG)
611 /* Extended frames remote TX request */
612 id |= XCAN_IDR_RTR_MASK;
614 /* Standard CAN ID format */
615 id = ((cf->can_id & CAN_SFF_MASK) << XCAN_IDR_ID1_SHIFT) &
618 if (cf->can_id & CAN_RTR_FLAG)
619 /* Standard frames remote TX request */
620 id |= XCAN_IDR_SRR_MASK;
623 dlc = can_len2dlc(cf->len) << XCAN_DLCR_DLC_SHIFT;
624 if (priv->quirks & CANFD_SUPPORT) {
625 if (can_is_canfd_skb(skb)) {
626 if (cf->flags & CANFD_BRS)
627 dlc |= XCAN_DLCR_BRS_MASK;
628 dlc |= XCAN_DLCR_EDL_MASK;
631 can_put_echo_skb(skb, ndev, priv->tx_head % priv->tx_max);
633 buffnr = xcan_get_freebuffer(priv);
635 netif_stop_queue(ndev);
637 priv->write_reg(priv, XCANFD_TXID_OFFSET(buffnr), id);
638 priv->write_reg(priv, XCANFD_TXDLC_OFFSET(buffnr), dlc);
640 for (i = 0; i < cf->len; i += 4) {
641 ramoff = XCANFD_TXDW_OFFSET(buffnr) + (dwindex *
643 priv->write_reg(priv, ramoff,
644 be32_to_cpup((__be32 *)(cf->data + i)));
648 trrval = priv->read_reg(priv, XCAN_TRR_OFFSET);
649 trrval |= 1 << buffnr;
650 priv->write_reg(priv, XCAN_TRR_OFFSET, trrval);
651 stats->tx_bytes += cf->len;
653 netif_stop_queue(ndev);
656 data[0] = be32_to_cpup((__be32 *)(cf->data + 0));
658 data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
660 can_put_echo_skb(skb, ndev, priv->tx_head % priv->tx_max);
663 /* Write the Frame to Xilinx CAN TX FIFO */
664 priv->write_reg(priv, XCAN_TXFIFO_ID_OFFSET, id);
665 /* If the CAN frame is RTR frame this write triggers
668 priv->write_reg(priv, XCAN_TXFIFO_DLC_OFFSET, dlc);
669 if (!(cf->can_id & CAN_RTR_FLAG)) {
670 priv->write_reg(priv, XCAN_TXFIFO_DW1_OFFSET, data[0]);
671 /* If the CAN frame is Standard/Extended frame this
672 * write triggers tranmission
674 priv->write_reg(priv, XCAN_TXFIFO_DW2_OFFSET, data[1]);
675 stats->tx_bytes += cf->len;
678 /* Check if the TX buffer is full */
679 if ((priv->tx_head - priv->tx_tail) == priv->tx_max)
680 netif_stop_queue(ndev);
686 * xcan_rx - Is called from CAN isr to complete the received
688 * @ndev: Pointer to net_device structure
690 * This function is invoked from the CAN isr(poll) to process the Rx frames. It
691 * does minimal processing and invokes "netif_receive_skb" to complete further
693 * Return: 1 on success and 0 on failure.
695 static int xcan_rx(struct net_device *ndev)
697 struct xcan_priv *priv = netdev_priv(ndev);
698 struct net_device_stats *stats = &ndev->stats;
699 struct can_frame *cf;
701 u32 id_xcan, dlc, data[2] = {0, 0};
703 /* Read a frame from Xilinx zynq CANPS */
704 id_xcan = priv->read_reg(priv, XCAN_RXFIFO_ID_OFFSET);
705 dlc = priv->read_reg(priv, XCAN_RXFIFO_DLC_OFFSET) >>
707 skb = alloc_can_skb(ndev, &cf);
708 if (unlikely(!skb)) {
713 /* Change Xilinx CAN data length format to socketCAN data format */
714 cf->can_dlc = get_can_dlc(dlc);
716 /* Change Xilinx CAN ID format to socketCAN ID format */
717 if (id_xcan & XCAN_IDR_IDE_MASK) {
718 /* The received frame is an Extended format frame */
719 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >> 3;
720 cf->can_id |= (id_xcan & XCAN_IDR_ID2_MASK) >>
722 cf->can_id |= CAN_EFF_FLAG;
723 if (id_xcan & XCAN_IDR_RTR_MASK)
724 cf->can_id |= CAN_RTR_FLAG;
726 /* The received frame is a standard format frame */
727 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >>
729 if (id_xcan & XCAN_IDR_SRR_MASK)
730 cf->can_id |= CAN_RTR_FLAG;
733 /* DW1/DW2 must always be read to remove message from RXFIFO */
734 data[0] = priv->read_reg(priv, XCAN_RXFIFO_DW1_OFFSET);
735 data[1] = priv->read_reg(priv, XCAN_RXFIFO_DW2_OFFSET);
737 if (!(cf->can_id & CAN_RTR_FLAG)) {
738 /* Change Xilinx CAN data format to socketCAN data format */
740 *(__be32 *)(cf->data) = cpu_to_be32(data[0]);
742 *(__be32 *)(cf->data + 4) = cpu_to_be32(data[1]);
745 stats->rx_bytes += cf->can_dlc;
747 netif_receive_skb(skb);
753 * xcanfd_rx - Is called from CAN isr to complete the received
755 * @ndev: Pointer to net_device structure
757 * This function is invoked from the CAN isr(poll) to process the Rx frames. It
758 * does minimal processing and invokes "netif_receive_skb" to complete further
760 * Return: 1 on success and 0 on failure.
762 static int xcanfd_rx(struct net_device *ndev)
764 struct xcan_priv *priv = netdev_priv(ndev);
765 struct net_device_stats *stats = &ndev->stats;
766 struct canfd_frame *cf;
768 u32 id_xcan, dlc, data[2] = {0, 0}, dwindex = 0, i, fsr, readindex;
770 fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
771 if (fsr & XCAN_FSR_FL_MASK) {
772 readindex = fsr & XCAN_FSR_RI_MASK;
773 id_xcan = priv->read_reg(priv, XCANFD_RXID_OFFSET(readindex));
774 dlc = priv->read_reg(priv, XCANFD_RXDLC_OFFSET(readindex));
775 if (dlc & XCAN_DLCR_EDL_MASK)
776 skb = alloc_canfd_skb(ndev, &cf);
778 skb = alloc_can_skb(ndev, (struct can_frame **)&cf);
780 if (unlikely(!skb)) {
785 /* Change Xilinx CANFD data length format to socketCAN data
788 if (dlc & XCAN_DLCR_EDL_MASK)
789 cf->len = can_dlc2len((dlc & XCAN_DLCR_DLC_MASK) >>
790 XCAN_DLCR_DLC_SHIFT);
792 cf->len = get_can_dlc((dlc & XCAN_DLCR_DLC_MASK) >>
793 XCAN_DLCR_DLC_SHIFT);
795 /* Change Xilinx CAN ID format to socketCAN ID format */
796 if (id_xcan & XCAN_IDR_IDE_MASK) {
797 /* The received frame is an Extended format frame */
798 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >> 3;
799 cf->can_id |= (id_xcan & XCAN_IDR_ID2_MASK) >>
801 cf->can_id |= CAN_EFF_FLAG;
802 if (id_xcan & XCAN_IDR_RTR_MASK)
803 cf->can_id |= CAN_RTR_FLAG;
805 /* The received frame is a standard format frame */
806 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >>
808 if (!(dlc & XCAN_DLCR_EDL_MASK) && (id_xcan &
810 cf->can_id |= CAN_RTR_FLAG;
813 /* Check the frame received is FD or not*/
814 if (dlc & XCAN_DLCR_EDL_MASK) {
815 for (i = 0; i < cf->len; i += 4) {
816 data[0] = priv->read_reg(priv,
817 (XCANFD_RXDW_OFFSET(readindex) +
818 (dwindex * XCANFD_DW_BYTES)));
819 *(__be32 *)(cf->data + i) = cpu_to_be32(
824 for (i = 0; i < cf->len; i += 4) {
825 data[0] = priv->read_reg(priv,
826 XCANFD_RXDW_OFFSET(readindex) + i);
827 *(__be32 *)(cf->data + i) = cpu_to_be32(
831 /* Update FSR Register so that next packet will save to
834 fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
835 fsr |= XCAN_FSR_IRI_MASK;
836 priv->write_reg(priv, XCAN_FSR_OFFSET, fsr);
837 fsr = priv->read_reg(priv, XCAN_FSR_OFFSET);
838 stats->rx_bytes += cf->len;
840 netif_receive_skb(skb);
844 /* If FSR Register is not updated with fill level */
848 static void xcan_chip_stop(struct net_device *ndev);
850 * xcan_err_interrupt - error frame Isr
851 * @ndev: net_device pointer
852 * @isr: interrupt status register value
854 * This is the CAN error interrupt and it will
855 * check the the type of error and forward the error
856 * frame to upper layers.
858 static void xcan_err_interrupt(struct net_device *ndev, u32 isr)
860 struct xcan_priv *priv = netdev_priv(ndev);
861 struct net_device_stats *stats = &ndev->stats;
862 struct can_frame *cf;
864 u32 err_status, status, txerr = 0, rxerr = 0;
866 skb = alloc_can_err_skb(ndev, &cf);
868 err_status = priv->read_reg(priv, XCAN_ESR_OFFSET);
869 priv->write_reg(priv, XCAN_ESR_OFFSET, err_status);
870 txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
871 rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
872 XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);
873 status = priv->read_reg(priv, XCAN_SR_OFFSET);
875 if (isr & XCAN_IXR_BSOFF_MASK) {
876 priv->can.state = CAN_STATE_BUS_OFF;
877 priv->can.can_stats.bus_off++;
878 /* Leave device in Config Mode in bus-off state */
879 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
882 cf->can_id |= CAN_ERR_BUSOFF;
883 } else if ((status & XCAN_SR_ESTAT_MASK) == XCAN_SR_ESTAT_MASK) {
884 priv->can.state = CAN_STATE_ERROR_PASSIVE;
885 priv->can.can_stats.error_passive++;
887 cf->can_id |= CAN_ERR_CRTL;
888 cf->data[1] = (rxerr > 127) ?
889 CAN_ERR_CRTL_RX_PASSIVE :
890 CAN_ERR_CRTL_TX_PASSIVE;
894 } else if (status & XCAN_SR_ERRWRN_MASK) {
895 priv->can.state = CAN_STATE_ERROR_WARNING;
896 priv->can.can_stats.error_warning++;
898 cf->can_id |= CAN_ERR_CRTL;
899 cf->data[1] |= (txerr > rxerr) ?
900 CAN_ERR_CRTL_TX_WARNING :
901 CAN_ERR_CRTL_RX_WARNING;
907 /* Check for Arbitration lost interrupt */
908 if (isr & XCAN_IXR_ARBLST_MASK) {
909 priv->can.can_stats.arbitration_lost++;
911 cf->can_id |= CAN_ERR_LOSTARB;
912 cf->data[0] = CAN_ERR_LOSTARB_UNSPEC;
916 /* Check for RX FIFO Overflow interrupt */
917 if (isr & XCAN_IXR_RXOFLW_MASK) {
918 stats->rx_over_errors++;
920 xcan_chip_stop(ndev);
921 xcan_chip_start(ndev);
923 cf->can_id |= CAN_ERR_CRTL;
924 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
928 /* Check for error interrupt */
929 if (isr & XCAN_IXR_ERROR_MASK) {
931 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
933 /* Check for Ack error interrupt */
934 if (err_status & XCAN_ESR_ACKER_MASK) {
937 cf->can_id |= CAN_ERR_ACK;
938 cf->data[3] = CAN_ERR_PROT_LOC_ACK;
942 /* Check for Bit error interrupt */
943 if (err_status & XCAN_ESR_BERR_MASK) {
946 cf->can_id |= CAN_ERR_PROT;
947 cf->data[2] = CAN_ERR_PROT_BIT;
951 /* Check for Stuff error interrupt */
952 if (err_status & XCAN_ESR_STER_MASK) {
955 cf->can_id |= CAN_ERR_PROT;
956 cf->data[2] = CAN_ERR_PROT_STUFF;
960 /* Check for Form error interrupt */
961 if (err_status & XCAN_ESR_FMER_MASK) {
964 cf->can_id |= CAN_ERR_PROT;
965 cf->data[2] = CAN_ERR_PROT_FORM;
969 /* Check for CRC error interrupt */
970 if (err_status & XCAN_ESR_CRCER_MASK) {
973 cf->can_id |= CAN_ERR_PROT;
974 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
977 if (priv->quirks & CANFD_SUPPORT) {
978 /* Check for Fast Bit error interrupt */
979 if (err_status & XCAN_ESR_F_BERR_MASK) {
982 cf->can_id |= CAN_ERR_PROT;
983 cf->data[2] = CAN_ERR_PROT_BIT;
986 /* Check for Stuff error interrupt */
987 if (err_status & XCAN_ESR_F_STER_MASK) {
990 cf->can_id |= CAN_ERR_PROT;
991 cf->data[2] = CAN_ERR_PROT_STUFF;
994 /* Check for Fast Form error interrupt */
995 if (err_status & XCAN_ESR_F_FMER_MASK) {
998 cf->can_id |= CAN_ERR_PROT;
999 cf->data[2] = CAN_ERR_PROT_FORM;
1002 if (err_status & XCAN_ESR_F_CRCER_MASK) {
1005 cf->can_id |= CAN_ERR_PROT;
1006 priv->can.can_stats.bus_error++;
1010 priv->can.can_stats.bus_error++;
1014 stats->rx_packets++;
1015 stats->rx_bytes += cf->can_dlc;
1019 netdev_dbg(ndev, "%s: error status register:0x%x\n",
1020 __func__, priv->read_reg(priv, XCAN_ESR_OFFSET));
1024 * xcan_state_interrupt - It will check the state of the CAN device
1025 * @ndev: net_device pointer
1026 * @isr: interrupt status register value
1028 * This will checks the state of the CAN device
1029 * and puts the device into appropriate state.
1031 static void xcan_state_interrupt(struct net_device *ndev, u32 isr)
1033 struct xcan_priv *priv = netdev_priv(ndev);
1035 /* Check for Sleep interrupt if set put CAN device in sleep state */
1036 if (isr & XCAN_IXR_SLP_MASK)
1037 priv->can.state = CAN_STATE_SLEEPING;
1039 /* Check for Wake up interrupt if set put CAN device in Active state */
1040 if (isr & XCAN_IXR_WKUP_MASK)
1041 priv->can.state = CAN_STATE_ERROR_ACTIVE;
1045 * xcan_rx_poll - Poll routine for rx packets (NAPI)
1046 * @napi: napi structure pointer
1047 * @quota: Max number of rx packets to be processed.
1049 * This is the poll routine for rx part.
1050 * It will process the packets maximux quota value.
1052 * Return: number of packets received
1054 static int xcan_rx_poll(struct napi_struct *napi, int quota)
1056 struct net_device *ndev = napi->dev;
1057 struct xcan_priv *priv = netdev_priv(ndev);
1059 int work_done = 0, rx_bit_mask;
1061 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1062 rx_bit_mask = ((priv->quirks & CANFD_SUPPORT) ?
1063 XCAN_IXR_RXOK_MASK : XCAN_IXR_RXNEMP_MASK);
1064 while ((isr & rx_bit_mask) && (work_done < quota)) {
1065 if (rx_bit_mask & XCAN_IXR_RXOK_MASK)
1066 work_done += xcanfd_rx(ndev);
1068 work_done += xcan_rx(ndev);
1069 priv->write_reg(priv, XCAN_ICR_OFFSET, rx_bit_mask);
1070 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1074 can_led_event(ndev, CAN_LED_EVENT_RX);
1076 if (work_done < quota) {
1077 napi_complete(napi);
1078 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
1080 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
1086 * xcan_tx_interrupt - Tx Done Isr
1087 * @ndev: net_device pointer
1088 * @isr: Interrupt status register value
1090 static void xcan_tx_interrupt(struct net_device *ndev, u32 isr)
1092 struct xcan_priv *priv = netdev_priv(ndev);
1093 struct net_device_stats *stats = &ndev->stats;
1095 while ((priv->tx_head - priv->tx_tail > 0) &&
1096 (isr & XCAN_IXR_TXOK_MASK)) {
1097 priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXOK_MASK);
1098 can_get_echo_skb(ndev, priv->tx_tail %
1101 stats->tx_packets++;
1102 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1104 can_led_event(ndev, CAN_LED_EVENT_TX);
1105 netif_wake_queue(ndev);
1109 * xcan_interrupt - CAN Isr
1111 * @dev_id: device id poniter
1113 * This is the xilinx CAN Isr. It checks for the type of interrupt
1114 * and invokes the corresponding ISR.
1117 * IRQ_NONE - If CAN device is in sleep mode, IRQ_HANDLED otherwise
1119 static irqreturn_t xcan_interrupt(int irq, void *dev_id)
1121 struct net_device *ndev = (struct net_device *)dev_id;
1122 struct xcan_priv *priv = netdev_priv(ndev);
1123 u32 isr, ier, rx_bit_mask;
1125 /* Get the interrupt status from Xilinx CAN */
1126 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1130 /* Check for the type of interrupt and Processing it */
1131 if (isr & (XCAN_IXR_SLP_MASK | XCAN_IXR_WKUP_MASK)) {
1132 priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_SLP_MASK |
1133 XCAN_IXR_WKUP_MASK));
1134 xcan_state_interrupt(ndev, isr);
1137 /* Check for Tx interrupt and Processing it */
1138 if (isr & XCAN_IXR_TXOK_MASK)
1139 xcan_tx_interrupt(ndev, isr);
1141 /* Check for the type of error interrupt and Processing it */
1142 if (isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
1143 XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK)) {
1144 priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_ERROR_MASK |
1145 XCAN_IXR_RXOFLW_MASK | XCAN_IXR_BSOFF_MASK |
1146 XCAN_IXR_ARBLST_MASK));
1147 xcan_err_interrupt(ndev, isr);
1149 if (priv->quirks & CANFD_SUPPORT) {
1150 if (isr & (XCAN_IXR_RXMNF_MASK | XCAN_IXR_TXRRS_MASK |
1151 XCAN_IXR_PEE_MASK | XCAN_IXR_BSRD_MASK)) {
1152 priv->write_reg(priv, XCAN_ICR_OFFSET,
1153 (XCAN_IXR_RXMNF_MASK |
1154 XCAN_IXR_TXRRS_MASK |
1156 XCAN_IXR_BSRD_MASK));
1157 xcan_err_interrupt(ndev, isr);
1160 /* Check for the type of receive interrupt and Processing it */
1161 rx_bit_mask = ((priv->quirks & CANFD_SUPPORT) ?
1162 XCAN_IXR_RXOK_MASK : XCAN_IXR_RXNEMP_MASK);
1163 if (isr & rx_bit_mask) {
1164 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
1165 ier &= ~(rx_bit_mask);
1166 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
1167 napi_schedule(&priv->napi);
1173 * xcan_chip_stop - Driver stop routine
1174 * @ndev: Pointer to net_device structure
1176 * This is the drivers stop routine. It will disable the
1177 * interrupts and put the device into configuration mode.
1179 static void xcan_chip_stop(struct net_device *ndev)
1181 struct xcan_priv *priv = netdev_priv(ndev);
1182 u32 ier, intr_all = 0;
1184 /* Disable interrupts and leave the can in configuration mode */
1185 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
1186 if (priv->quirks & CANFD_SUPPORT) {
1187 intr_all = XCAN_INTR_ALL | XCAN_IXR_PEE_MASK |
1188 XCAN_IXR_BSRD_MASK | XCAN_IXR_RXMNF_MASK |
1189 XCAN_IXR_TXRRS_MASK | XCAN_IXR_RXOK_MASK;
1191 intr_all = XCAN_INTR_ALL | XCAN_IXR_RXNEMP_MASK;
1195 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
1196 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
1197 priv->can.state = CAN_STATE_STOPPED;
1201 * xcan_open - Driver open routine
1202 * @ndev: Pointer to net_device structure
1204 * This is the driver open routine.
1205 * Return: 0 on success and failure value on error
1207 static int xcan_open(struct net_device *ndev)
1209 struct xcan_priv *priv = netdev_priv(ndev);
1212 ret = pm_runtime_get_sync(priv->dev);
1214 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
1219 ret = request_irq(ndev->irq, xcan_interrupt, priv->irq_flags,
1222 netdev_err(ndev, "irq allocation for CAN failed\n");
1226 /* Set chip into reset mode */
1227 ret = set_reset_mode(ndev);
1229 netdev_err(ndev, "mode resetting failed!\n");
1234 ret = open_candev(ndev);
1238 ret = xcan_chip_start(ndev);
1240 netdev_err(ndev, "xcan_chip_start failed!\n");
1244 can_led_event(ndev, CAN_LED_EVENT_OPEN);
1245 napi_enable(&priv->napi);
1246 netif_start_queue(ndev);
1253 free_irq(ndev->irq, ndev);
1255 pm_runtime_put(priv->dev);
1261 * xcan_close - Driver close routine
1262 * @ndev: Pointer to net_device structure
1266 static int xcan_close(struct net_device *ndev)
1268 struct xcan_priv *priv = netdev_priv(ndev);
1270 netif_stop_queue(ndev);
1271 napi_disable(&priv->napi);
1272 xcan_chip_stop(ndev);
1273 free_irq(ndev->irq, ndev);
1276 can_led_event(ndev, CAN_LED_EVENT_STOP);
1277 pm_runtime_put(priv->dev);
1283 * xcan_get_berr_counter - error counter routine
1284 * @ndev: Pointer to net_device structure
1285 * @bec: Pointer to can_berr_counter structure
1287 * This is the driver error counter routine.
1288 * Return: 0 on success and failure value on error
1290 static int xcan_get_berr_counter(const struct net_device *ndev,
1291 struct can_berr_counter *bec)
1293 struct xcan_priv *priv = netdev_priv(ndev);
1296 ret = pm_runtime_get_sync(priv->dev);
1298 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
1303 bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
1304 bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
1305 XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);
1307 pm_runtime_put(priv->dev);
1312 static const struct net_device_ops xcan_netdev_ops = {
1313 .ndo_open = xcan_open,
1314 .ndo_stop = xcan_close,
1315 .ndo_start_xmit = xcan_start_xmit,
1316 .ndo_change_mtu = can_change_mtu,
1320 * xcan_suspend - Suspend method for the driver
1321 * @dev: Address of the device structure
1323 * Put the driver into low power mode.
1324 * Return: 0 on success and failure value on error
1326 static int __maybe_unused xcan_suspend(struct device *dev)
1328 struct net_device *netdev = dev_get_drvdata(dev);
1330 if (!device_may_wakeup(dev)) {
1331 if (netif_running(netdev))
1333 return pm_runtime_force_suspend(dev);
1340 * xcan_resume - Resume from suspend
1341 * @dev: Address of the device structure
1343 * Resume operation after suspend.
1344 * Return: 0 on success and failure value on error
1346 static int __maybe_unused xcan_resume(struct device *dev)
1349 struct net_device *netdev = dev_get_drvdata(dev);
1351 if (!device_may_wakeup(dev)) {
1352 ret = pm_runtime_force_resume(dev);
1353 if (netif_running(netdev))
1362 * xcan_runtime_suspend - Runtime suspend method for the driver
1363 * @dev: Address of the device structure
1365 * Put the driver into low power mode.
1368 static int __maybe_unused xcan_runtime_suspend(struct device *dev)
1370 struct net_device *ndev = dev_get_drvdata(dev);
1371 struct xcan_priv *priv = netdev_priv(ndev);
1373 if (netif_running(ndev)) {
1374 netif_stop_queue(ndev);
1375 netif_device_detach(ndev);
1378 priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK);
1379 priv->can.state = CAN_STATE_SLEEPING;
1381 clk_disable_unprepare(priv->bus_clk);
1382 clk_disable_unprepare(priv->can_clk);
1388 * xcan_runtime_resume - Runtime resume from suspend
1389 * @dev: Address of the device structure
1391 * Resume operation after suspend.
1392 * Return: 0 on success and failure value on error
1394 static int __maybe_unused xcan_runtime_resume(struct device *dev)
1396 struct net_device *ndev = dev_get_drvdata(dev);
1397 struct xcan_priv *priv = netdev_priv(ndev);
1401 ret = clk_prepare_enable(priv->bus_clk);
1403 dev_err(dev, "Cannot enable clock.\n");
1406 ret = clk_prepare_enable(priv->can_clk);
1408 dev_err(dev, "Cannot enable clock.\n");
1409 clk_disable_unprepare(priv->bus_clk);
1413 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
1414 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1415 status = priv->read_reg(priv, XCAN_SR_OFFSET);
1417 if (netif_running(ndev)) {
1418 if (isr & XCAN_IXR_BSOFF_MASK) {
1419 priv->can.state = CAN_STATE_BUS_OFF;
1420 priv->write_reg(priv, XCAN_SRR_OFFSET,
1421 XCAN_SRR_RESET_MASK);
1422 } else if ((status & XCAN_SR_ESTAT_MASK) ==
1423 XCAN_SR_ESTAT_MASK) {
1424 priv->can.state = CAN_STATE_ERROR_PASSIVE;
1425 } else if (status & XCAN_SR_ERRWRN_MASK) {
1426 priv->can.state = CAN_STATE_ERROR_WARNING;
1428 priv->can.state = CAN_STATE_ERROR_ACTIVE;
1430 netif_device_attach(ndev);
1431 netif_start_queue(ndev);
1437 static const struct dev_pm_ops xcan_dev_pm_ops = {
1438 SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume)
1439 SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL)
1442 static const struct xcan_platform_data xcan_def = {
1443 .quirks = CANFD_SUPPORT,
1446 /* Match table for OF platform binding */
1447 static const struct of_device_id xcan_of_match[] = {
1448 { .compatible = "xlnx,zynq-can-1.0", },
1449 { .compatible = "xlnx,axi-can-1.00.a", },
1450 { .compatible = "xlnx,canfd-1.0", .data = &xcan_def },
1451 { /* end of list */ },
1453 MODULE_DEVICE_TABLE(of, xcan_of_match);
1456 * xcan_probe - Platform registration call
1457 * @pdev: Handle to the platform device structure
1459 * This function does all the memory allocation and registration for the CAN
1462 * Return: 0 on success and failure value on error
1464 static int xcan_probe(struct platform_device *pdev)
1466 struct resource *res; /* IO mem resources */
1467 struct net_device *ndev;
1468 struct xcan_priv *priv;
1469 const struct of_device_id *match;
1471 int ret, rx_max, tx_max;
1473 /* Get the virtual base address for the device */
1474 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1475 addr = devm_ioremap_resource(&pdev->dev, res);
1477 ret = PTR_ERR(addr);
1481 ret = of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth", &tx_max);
1485 ret = of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth", &rx_max);
1489 /* Create a CAN device instance */
1490 ndev = alloc_candev(sizeof(struct xcan_priv), tx_max);
1494 priv = netdev_priv(ndev);
1496 match = of_match_node(xcan_of_match, pdev->dev.of_node);
1497 if (match && match->data) {
1498 const struct xcan_platform_data *data = match->data;
1500 priv->quirks = data->quirks;
1503 priv->dev = &pdev->dev;
1504 priv->can.bittiming_const = &xcan_bittiming_const;
1505 priv->can.do_set_mode = xcan_do_set_mode;
1506 priv->can.do_get_berr_counter = xcan_get_berr_counter;
1507 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1508 CAN_CTRLMODE_BERR_REPORTING;
1509 if (priv->quirks & CANFD_SUPPORT) {
1510 priv->can.data_bittiming_const = &xcan_data_bittiming_const;
1511 priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
1512 xcan_bittiming_const.tseg1_max = 64;
1513 xcan_bittiming_const.tseg2_max = 16;
1514 xcan_bittiming_const.sjw_max = 16;
1516 priv->reg_base = addr;
1517 priv->tx_max = tx_max;
1521 /* Get IRQ for the device */
1522 ndev->irq = platform_get_irq(pdev, 0);
1523 ndev->flags |= IFF_ECHO; /* We support local echo */
1525 platform_set_drvdata(pdev, ndev);
1526 SET_NETDEV_DEV(ndev, &pdev->dev);
1527 ndev->netdev_ops = &xcan_netdev_ops;
1529 /* Getting the CAN can_clk info */
1530 priv->can_clk = devm_clk_get(&pdev->dev, "can_clk");
1531 if (IS_ERR(priv->can_clk)) {
1532 dev_err(&pdev->dev, "Device clock not found.\n");
1533 ret = PTR_ERR(priv->can_clk);
1536 /* Check for type of CAN device */
1537 if (of_device_is_compatible(pdev->dev.of_node,
1538 "xlnx,zynq-can-1.0")) {
1539 priv->bus_clk = devm_clk_get(&pdev->dev, "pclk");
1540 if (IS_ERR(priv->bus_clk)) {
1541 dev_err(&pdev->dev, "bus clock not found\n");
1542 ret = PTR_ERR(priv->bus_clk);
1546 priv->bus_clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
1547 if (IS_ERR(priv->bus_clk)) {
1548 dev_err(&pdev->dev, "bus clock not found\n");
1549 ret = PTR_ERR(priv->bus_clk);
1554 priv->write_reg = xcan_write_reg_le;
1555 priv->read_reg = xcan_read_reg_le;
1557 ret = clk_prepare_enable(priv->bus_clk);
1559 dev_err(&pdev->dev, "Cannot enable clock.\n");
1563 ret = clk_prepare_enable(priv->can_clk);
1565 dev_err(&pdev->dev, "Cannot enable clock.\n");
1569 pm_runtime_set_active(&pdev->dev);
1570 pm_runtime_enable(&pdev->dev);
1571 pm_runtime_get_sync(&pdev->dev);
1573 if (priv->read_reg(priv, XCAN_SR_OFFSET) != XCAN_SR_CONFIG_MASK) {
1574 priv->write_reg = xcan_write_reg_be;
1575 priv->read_reg = xcan_read_reg_be;
1578 priv->can.clock.freq = clk_get_rate(priv->can_clk);
1580 netif_napi_add(ndev, &priv->napi, xcan_rx_poll, rx_max);
1582 ret = register_candev(ndev);
1584 dev_err(&pdev->dev, "fail to register failed (err=%d)\n", ret);
1585 goto err_disableclks;
1588 devm_can_led_init(ndev);
1590 pm_runtime_put(&pdev->dev);
1592 netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth:%d\n",
1593 priv->reg_base, ndev->irq, priv->can.clock.freq,
1599 pm_runtime_disable(&pdev->dev);
1600 pm_runtime_set_suspended(&pdev->dev);
1601 clk_disable_unprepare(priv->can_clk);
1603 clk_disable_unprepare(priv->bus_clk);
1611 * xcan_remove - Unregister the device after releasing the resources
1612 * @pdev: Handle to the platform device structure
1614 * This function frees all the resources allocated to the device.
1617 static int xcan_remove(struct platform_device *pdev)
1619 struct net_device *ndev = platform_get_drvdata(pdev);
1620 struct xcan_priv *priv = netdev_priv(ndev);
1622 unregister_candev(ndev);
1624 if (!pm_runtime_suspended(&pdev->dev)) {
1625 clk_disable_unprepare(priv->bus_clk);
1626 clk_disable_unprepare(priv->can_clk);
1629 pm_runtime_disable(&pdev->dev);
1630 netif_napi_del(&priv->napi);
1636 static struct platform_driver xcan_driver = {
1637 .probe = xcan_probe,
1638 .remove = xcan_remove,
1640 .name = DRIVER_NAME,
1641 .pm = &xcan_dev_pm_ops,
1642 .of_match_table = xcan_of_match,
1646 module_platform_driver(xcan_driver);
1648 MODULE_LICENSE("GPL");
1649 MODULE_AUTHOR("Xilinx Inc");
1650 MODULE_DESCRIPTION("Xilinx CAN interface");