xref: /openbmc/linux/drivers/net/can/kvaser_pciefd.c (revision e2942062)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
2 /* Copyright (C) 2018 KVASER AB, Sweden. All rights reserved.
3  * Parts of this driver are based on the following:
4  *  - Kvaser linux pciefd driver (version 5.25)
5  *  - PEAK linux canfd driver
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/can/dev.h>
10 #include <linux/device.h>
11 #include <linux/ethtool.h>
12 #include <linux/iopoll.h>
13 #include <linux/kernel.h>
14 #include <linux/minmax.h>
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
17 #include <linux/pci.h>
18 #include <linux/timer.h>
19 
20 MODULE_LICENSE("Dual BSD/GPL");
21 MODULE_AUTHOR("Kvaser AB <support@kvaser.com>");
22 MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
23 
24 #define KVASER_PCIEFD_DRV_NAME "kvaser_pciefd"
25 
26 #define KVASER_PCIEFD_WAIT_TIMEOUT msecs_to_jiffies(1000)
27 #define KVASER_PCIEFD_BEC_POLL_FREQ (jiffies + msecs_to_jiffies(200))
28 #define KVASER_PCIEFD_MAX_ERR_REP 256U
29 #define KVASER_PCIEFD_CAN_TX_MAX_COUNT 17U
30 #define KVASER_PCIEFD_MAX_CAN_CHANNELS 4UL
31 #define KVASER_PCIEFD_DMA_COUNT 2U
32 
33 #define KVASER_PCIEFD_DMA_SIZE (4U * 1024U)
34 
35 #define KVASER_PCIEFD_VENDOR 0x1a07
36 #define KVASER_PCIEFD_4HS_DEVICE_ID 0x000d
37 #define KVASER_PCIEFD_2HS_V2_DEVICE_ID 0x000e
38 #define KVASER_PCIEFD_HS_V2_DEVICE_ID 0x000f
39 #define KVASER_PCIEFD_MINIPCIE_HS_V2_DEVICE_ID 0x0010
40 #define KVASER_PCIEFD_MINIPCIE_2HS_V2_DEVICE_ID 0x0011
41 
42 /* PCIe IRQ registers */
43 #define KVASER_PCIEFD_IRQ_REG 0x40
44 #define KVASER_PCIEFD_IEN_REG 0x50
45 /* DMA address translation map register base */
46 #define KVASER_PCIEFD_DMA_MAP_BASE 0x1000
47 /* Loopback control register */
48 #define KVASER_PCIEFD_LOOP_REG 0x1f000
49 /* System identification and information registers */
50 #define KVASER_PCIEFD_SYSID_BASE 0x1f020
51 #define KVASER_PCIEFD_SYSID_VERSION_REG (KVASER_PCIEFD_SYSID_BASE + 0x8)
52 #define KVASER_PCIEFD_SYSID_CANFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0xc)
53 #define KVASER_PCIEFD_SYSID_BUSFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0x10)
54 #define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
55 /* Shared receive buffer registers */
56 #define KVASER_PCIEFD_SRB_BASE 0x1f200
57 #define KVASER_PCIEFD_SRB_FIFO_LAST_REG (KVASER_PCIEFD_SRB_BASE + 0x1f4)
58 #define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
59 #define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
60 #define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
61 #define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
62 #define KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG (KVASER_PCIEFD_SRB_BASE + 0x214)
63 #define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
64 /* Kvaser KCAN CAN controller registers */
65 #define KVASER_PCIEFD_KCAN0_BASE 0x10000
66 #define KVASER_PCIEFD_KCAN_BASE_OFFSET 0x1000
67 #define KVASER_PCIEFD_KCAN_FIFO_REG 0x100
68 #define KVASER_PCIEFD_KCAN_FIFO_LAST_REG 0x180
69 #define KVASER_PCIEFD_KCAN_CTRL_REG 0x2c0
70 #define KVASER_PCIEFD_KCAN_CMD_REG 0x400
71 #define KVASER_PCIEFD_KCAN_IEN_REG 0x408
72 #define KVASER_PCIEFD_KCAN_IRQ_REG 0x410
73 #define KVASER_PCIEFD_KCAN_TX_NR_PACKETS_REG 0x414
74 #define KVASER_PCIEFD_KCAN_STAT_REG 0x418
75 #define KVASER_PCIEFD_KCAN_MODE_REG 0x41c
76 #define KVASER_PCIEFD_KCAN_BTRN_REG 0x420
77 #define KVASER_PCIEFD_KCAN_BUS_LOAD_REG 0x424
78 #define KVASER_PCIEFD_KCAN_BTRD_REG 0x428
79 #define KVASER_PCIEFD_KCAN_PWM_REG 0x430
80 
81 /* PCI interrupt fields */
82 #define KVASER_PCIEFD_IRQ_SRB BIT(4)
83 #define KVASER_PCIEFD_IRQ_ALL_MASK GENMASK(4, 0)
84 
85 /* Enable 64-bit DMA address translation */
86 #define KVASER_PCIEFD_64BIT_DMA_BIT BIT(0)
87 
88 /* System build information fields */
89 #define KVASER_PCIEFD_SYSID_VERSION_NR_CHAN_MASK GENMASK(31, 24)
90 #define KVASER_PCIEFD_SYSID_VERSION_MAJOR_MASK GENMASK(23, 16)
91 #define KVASER_PCIEFD_SYSID_VERSION_MINOR_MASK GENMASK(7, 0)
92 #define KVASER_PCIEFD_SYSID_BUILD_SEQ_MASK GENMASK(15, 1)
93 
94 /* Reset DMA buffer 0, 1 and FIFO offset */
95 #define KVASER_PCIEFD_SRB_CMD_RDB1 BIT(5)
96 #define KVASER_PCIEFD_SRB_CMD_RDB0 BIT(4)
97 #define KVASER_PCIEFD_SRB_CMD_FOR BIT(0)
98 
99 /* DMA underflow, buffer 0 and 1 */
100 #define KVASER_PCIEFD_SRB_IRQ_DUF1 BIT(13)
101 #define KVASER_PCIEFD_SRB_IRQ_DUF0 BIT(12)
102 /* DMA overflow, buffer 0 and 1 */
103 #define KVASER_PCIEFD_SRB_IRQ_DOF1 BIT(11)
104 #define KVASER_PCIEFD_SRB_IRQ_DOF0 BIT(10)
105 /* DMA packet done, buffer 0 and 1 */
106 #define KVASER_PCIEFD_SRB_IRQ_DPD1 BIT(9)
107 #define KVASER_PCIEFD_SRB_IRQ_DPD0 BIT(8)
108 
109 /* Got DMA support */
110 #define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
111 /* DMA idle */
112 #define KVASER_PCIEFD_SRB_STAT_DI BIT(15)
113 
114 /* SRB current packet level */
115 #define KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK GENMASK(7, 0)
116 
117 /* DMA Enable */
118 #define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
119 
120 /* KCAN CTRL packet types */
121 #define KVASER_PCIEFD_KCAN_CTRL_TYPE_MASK GENMASK(31, 29)
122 #define KVASER_PCIEFD_KCAN_CTRL_TYPE_EFLUSH 0x4
123 #define KVASER_PCIEFD_KCAN_CTRL_TYPE_EFRAME 0x5
124 
125 /* Command sequence number */
126 #define KVASER_PCIEFD_KCAN_CMD_SEQ_MASK GENMASK(23, 16)
127 /* Command bits */
128 #define KVASER_PCIEFD_KCAN_CMD_MASK GENMASK(5, 0)
129 /* Abort, flush and reset */
130 #define KVASER_PCIEFD_KCAN_CMD_AT BIT(1)
131 /* Request status packet */
132 #define KVASER_PCIEFD_KCAN_CMD_SRQ BIT(0)
133 
134 /* Transmitter unaligned */
135 #define KVASER_PCIEFD_KCAN_IRQ_TAL BIT(17)
136 /* Tx FIFO empty */
137 #define KVASER_PCIEFD_KCAN_IRQ_TE BIT(16)
138 /* Tx FIFO overflow */
139 #define KVASER_PCIEFD_KCAN_IRQ_TOF BIT(15)
140 /* Tx buffer flush done */
141 #define KVASER_PCIEFD_KCAN_IRQ_TFD BIT(14)
142 /* Abort done */
143 #define KVASER_PCIEFD_KCAN_IRQ_ABD BIT(13)
144 /* Rx FIFO overflow */
145 #define KVASER_PCIEFD_KCAN_IRQ_ROF BIT(5)
146 /* FDF bit when controller is in classic CAN mode */
147 #define KVASER_PCIEFD_KCAN_IRQ_FDIC BIT(3)
148 /* Bus parameter protection error */
149 #define KVASER_PCIEFD_KCAN_IRQ_BPP BIT(2)
150 /* Tx FIFO unaligned end */
151 #define KVASER_PCIEFD_KCAN_IRQ_TAE BIT(1)
152 /* Tx FIFO unaligned read */
153 #define KVASER_PCIEFD_KCAN_IRQ_TAR BIT(0)
154 
155 /* Tx FIFO size */
156 #define KVASER_PCIEFD_KCAN_TX_NR_PACKETS_MAX_MASK GENMASK(23, 16)
157 /* Tx FIFO current packet level */
158 #define KVASER_PCIEFD_KCAN_TX_NR_PACKETS_CURRENT_MASK GENMASK(7, 0)
159 
160 /* Current status packet sequence number */
161 #define KVASER_PCIEFD_KCAN_STAT_SEQNO_MASK GENMASK(31, 24)
162 /* Controller got CAN FD capability */
163 #define KVASER_PCIEFD_KCAN_STAT_FD BIT(19)
164 /* Controller got one-shot capability */
165 #define KVASER_PCIEFD_KCAN_STAT_CAP BIT(16)
166 /* Controller in reset mode */
167 #define KVASER_PCIEFD_KCAN_STAT_IRM BIT(15)
168 /* Reset mode request */
169 #define KVASER_PCIEFD_KCAN_STAT_RMR BIT(14)
170 /* Bus off */
171 #define KVASER_PCIEFD_KCAN_STAT_BOFF BIT(11)
172 /* Idle state. Controller in reset mode and no abort or flush pending */
173 #define KVASER_PCIEFD_KCAN_STAT_IDLE BIT(10)
174 /* Abort request */
175 #define KVASER_PCIEFD_KCAN_STAT_AR BIT(7)
176 /* Controller is bus off */
177 #define KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MASK \
178 	(KVASER_PCIEFD_KCAN_STAT_AR | KVASER_PCIEFD_KCAN_STAT_BOFF | \
179 	 KVASER_PCIEFD_KCAN_STAT_RMR | KVASER_PCIEFD_KCAN_STAT_IRM)
180 
181 /* Classic CAN mode */
182 #define KVASER_PCIEFD_KCAN_MODE_CCM BIT(31)
183 /* Active error flag enable. Clear to force error passive */
184 #define KVASER_PCIEFD_KCAN_MODE_EEN BIT(23)
185 /* Acknowledgment packet type */
186 #define KVASER_PCIEFD_KCAN_MODE_APT BIT(20)
187 /* CAN FD non-ISO */
188 #define KVASER_PCIEFD_KCAN_MODE_NIFDEN BIT(15)
189 /* Error packet enable */
190 #define KVASER_PCIEFD_KCAN_MODE_EPEN BIT(12)
191 /* Listen only mode */
192 #define KVASER_PCIEFD_KCAN_MODE_LOM BIT(9)
193 /* Reset mode */
194 #define KVASER_PCIEFD_KCAN_MODE_RM BIT(8)
195 
196 /* BTRN and BTRD fields */
197 #define KVASER_PCIEFD_KCAN_BTRN_TSEG2_MASK GENMASK(30, 26)
198 #define KVASER_PCIEFD_KCAN_BTRN_TSEG1_MASK GENMASK(25, 17)
199 #define KVASER_PCIEFD_KCAN_BTRN_SJW_MASK GENMASK(16, 13)
200 #define KVASER_PCIEFD_KCAN_BTRN_BRP_MASK GENMASK(12, 0)
201 
202 /* PWM Control fields */
203 #define KVASER_PCIEFD_KCAN_PWM_TOP_MASK GENMASK(23, 16)
204 #define KVASER_PCIEFD_KCAN_PWM_TRIGGER_MASK GENMASK(7, 0)
205 
206 /* KCAN packet type IDs */
207 #define KVASER_PCIEFD_PACK_TYPE_DATA 0x0
208 #define KVASER_PCIEFD_PACK_TYPE_ACK 0x1
209 #define KVASER_PCIEFD_PACK_TYPE_TXRQ 0x2
210 #define KVASER_PCIEFD_PACK_TYPE_ERROR 0x3
211 #define KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK 0x4
212 #define KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK 0x5
213 #define KVASER_PCIEFD_PACK_TYPE_ACK_DATA 0x6
214 #define KVASER_PCIEFD_PACK_TYPE_STATUS 0x8
215 #define KVASER_PCIEFD_PACK_TYPE_BUS_LOAD 0x9
216 
217 /* Common KCAN packet definitions, second word */
218 #define KVASER_PCIEFD_PACKET_TYPE_MASK GENMASK(31, 28)
219 #define KVASER_PCIEFD_PACKET_CHID_MASK GENMASK(27, 25)
220 #define KVASER_PCIEFD_PACKET_SEQ_MASK GENMASK(7, 0)
221 
222 /* KCAN Transmit/Receive data packet, first word */
223 #define KVASER_PCIEFD_RPACKET_IDE BIT(30)
224 #define KVASER_PCIEFD_RPACKET_RTR BIT(29)
225 #define KVASER_PCIEFD_RPACKET_ID_MASK GENMASK(28, 0)
226 /* KCAN Transmit data packet, second word */
227 #define KVASER_PCIEFD_TPACKET_AREQ BIT(31)
228 #define KVASER_PCIEFD_TPACKET_SMS BIT(16)
229 /* KCAN Transmit/Receive data packet, second word */
230 #define KVASER_PCIEFD_RPACKET_FDF BIT(15)
231 #define KVASER_PCIEFD_RPACKET_BRS BIT(14)
232 #define KVASER_PCIEFD_RPACKET_ESI BIT(13)
233 #define KVASER_PCIEFD_RPACKET_DLC_MASK GENMASK(11, 8)
234 
235 /* KCAN Transmit acknowledge packet, first word */
236 #define KVASER_PCIEFD_APACKET_NACK BIT(11)
237 #define KVASER_PCIEFD_APACKET_ABL BIT(10)
238 #define KVASER_PCIEFD_APACKET_CT BIT(9)
239 #define KVASER_PCIEFD_APACKET_FLU BIT(8)
240 
241 /* KCAN Status packet, first word */
242 #define KVASER_PCIEFD_SPACK_RMCD BIT(22)
243 #define KVASER_PCIEFD_SPACK_IRM BIT(21)
244 #define KVASER_PCIEFD_SPACK_IDET BIT(20)
245 #define KVASER_PCIEFD_SPACK_BOFF BIT(16)
246 #define KVASER_PCIEFD_SPACK_RXERR_MASK GENMASK(15, 8)
247 #define KVASER_PCIEFD_SPACK_TXERR_MASK GENMASK(7, 0)
248 /* KCAN Status packet, second word */
249 #define KVASER_PCIEFD_SPACK_EPLR BIT(24)
250 #define KVASER_PCIEFD_SPACK_EWLR BIT(23)
251 #define KVASER_PCIEFD_SPACK_AUTO BIT(21)
252 
253 /* KCAN Error detected packet, second word */
254 #define KVASER_PCIEFD_EPACK_DIR_TX BIT(0)
255 
256 struct kvaser_pciefd;
257 
258 struct kvaser_pciefd_can {
259 	struct can_priv can;
260 	struct kvaser_pciefd *kv_pcie;
261 	void __iomem *reg_base;
262 	struct can_berr_counter bec;
263 	u8 cmd_seq;
264 	int err_rep_cnt;
265 	int echo_idx;
266 	spinlock_t lock; /* Locks sensitive registers (e.g. MODE) */
267 	spinlock_t echo_lock; /* Locks the message echo buffer */
268 	struct timer_list bec_poll_timer;
269 	struct completion start_comp, flush_comp;
270 };
271 
272 struct kvaser_pciefd {
273 	struct pci_dev *pci;
274 	void __iomem *reg_base;
275 	struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
276 	void *dma_data[KVASER_PCIEFD_DMA_COUNT];
277 	u8 nr_channels;
278 	u32 bus_freq;
279 	u32 freq;
280 	u32 freq_to_ticks_div;
281 };
282 
283 struct kvaser_pciefd_rx_packet {
284 	u32 header[2];
285 	u64 timestamp;
286 };
287 
288 struct kvaser_pciefd_tx_packet {
289 	u32 header[2];
290 	u8 data[64];
291 };
292 
293 static const struct can_bittiming_const kvaser_pciefd_bittiming_const = {
294 	.name = KVASER_PCIEFD_DRV_NAME,
295 	.tseg1_min = 1,
296 	.tseg1_max = 512,
297 	.tseg2_min = 1,
298 	.tseg2_max = 32,
299 	.sjw_max = 16,
300 	.brp_min = 1,
301 	.brp_max = 8192,
302 	.brp_inc = 1,
303 };
304 
305 static struct pci_device_id kvaser_pciefd_id_table[] = {
306 	{
307 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_4HS_DEVICE_ID),
308 	},
309 	{
310 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_2HS_V2_DEVICE_ID),
311 	},
312 	{
313 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_HS_V2_DEVICE_ID),
314 	},
315 	{
316 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_HS_V2_DEVICE_ID),
317 	},
318 	{
319 		PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_2HS_V2_DEVICE_ID),
320 	},
321 	{
322 		0,
323 	},
324 };
325 MODULE_DEVICE_TABLE(pci, kvaser_pciefd_id_table);
326 
327 static inline void kvaser_pciefd_send_kcan_cmd(struct kvaser_pciefd_can *can, u32 cmd)
328 {
329 	iowrite32(FIELD_PREP(KVASER_PCIEFD_KCAN_CMD_MASK, cmd) |
330 		  FIELD_PREP(KVASER_PCIEFD_KCAN_CMD_SEQ_MASK, ++can->cmd_seq),
331 		  can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
332 }
333 
334 static inline void kvaser_pciefd_request_status(struct kvaser_pciefd_can *can)
335 {
336 	kvaser_pciefd_send_kcan_cmd(can, KVASER_PCIEFD_KCAN_CMD_SRQ);
337 }
338 
339 static inline void kvaser_pciefd_abort_flush_reset(struct kvaser_pciefd_can *can)
340 {
341 	kvaser_pciefd_send_kcan_cmd(can, KVASER_PCIEFD_KCAN_CMD_AT);
342 }
343 
344 static void kvaser_pciefd_enable_err_gen(struct kvaser_pciefd_can *can)
345 {
346 	u32 mode;
347 	unsigned long irq;
348 
349 	spin_lock_irqsave(&can->lock, irq);
350 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
351 	if (!(mode & KVASER_PCIEFD_KCAN_MODE_EPEN)) {
352 		mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
353 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
354 	}
355 	spin_unlock_irqrestore(&can->lock, irq);
356 }
357 
358 static void kvaser_pciefd_disable_err_gen(struct kvaser_pciefd_can *can)
359 {
360 	u32 mode;
361 	unsigned long irq;
362 
363 	spin_lock_irqsave(&can->lock, irq);
364 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
365 	mode &= ~KVASER_PCIEFD_KCAN_MODE_EPEN;
366 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
367 	spin_unlock_irqrestore(&can->lock, irq);
368 }
369 
370 static void kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
371 {
372 	u32 msk;
373 
374 	msk = KVASER_PCIEFD_KCAN_IRQ_TE | KVASER_PCIEFD_KCAN_IRQ_ROF |
375 	      KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD |
376 	      KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL |
377 	      KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP |
378 	      KVASER_PCIEFD_KCAN_IRQ_TAR;
379 
380 	iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
381 }
382 
383 static inline void kvaser_pciefd_set_skb_timestamp(const struct kvaser_pciefd *pcie,
384 						   struct sk_buff *skb, u64 timestamp)
385 {
386 	skb_hwtstamps(skb)->hwtstamp =
387 		ns_to_ktime(div_u64(timestamp * 1000, pcie->freq_to_ticks_div));
388 }
389 
390 static void kvaser_pciefd_setup_controller(struct kvaser_pciefd_can *can)
391 {
392 	u32 mode;
393 	unsigned long irq;
394 
395 	spin_lock_irqsave(&can->lock, irq);
396 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
397 	if (can->can.ctrlmode & CAN_CTRLMODE_FD) {
398 		mode &= ~KVASER_PCIEFD_KCAN_MODE_CCM;
399 		if (can->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
400 			mode |= KVASER_PCIEFD_KCAN_MODE_NIFDEN;
401 		else
402 			mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
403 	} else {
404 		mode |= KVASER_PCIEFD_KCAN_MODE_CCM;
405 		mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
406 	}
407 
408 	if (can->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
409 		mode |= KVASER_PCIEFD_KCAN_MODE_LOM;
410 	else
411 		mode &= ~KVASER_PCIEFD_KCAN_MODE_LOM;
412 	mode |= KVASER_PCIEFD_KCAN_MODE_EEN;
413 	mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
414 	/* Use ACK packet type */
415 	mode &= ~KVASER_PCIEFD_KCAN_MODE_APT;
416 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
417 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
418 
419 	spin_unlock_irqrestore(&can->lock, irq);
420 }
421 
422 static void kvaser_pciefd_start_controller_flush(struct kvaser_pciefd_can *can)
423 {
424 	u32 status;
425 	unsigned long irq;
426 
427 	spin_lock_irqsave(&can->lock, irq);
428 	iowrite32(GENMASK(31, 0), can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
429 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
430 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
431 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
432 	if (status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
433 		/* If controller is already idle, run abort, flush and reset */
434 		kvaser_pciefd_abort_flush_reset(can);
435 	} else if (!(status & KVASER_PCIEFD_KCAN_STAT_RMR)) {
436 		u32 mode;
437 
438 		/* Put controller in reset mode */
439 		mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
440 		mode |= KVASER_PCIEFD_KCAN_MODE_RM;
441 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
442 	}
443 	spin_unlock_irqrestore(&can->lock, irq);
444 }
445 
446 static int kvaser_pciefd_bus_on(struct kvaser_pciefd_can *can)
447 {
448 	u32 mode;
449 	unsigned long irq;
450 
451 	del_timer(&can->bec_poll_timer);
452 	if (!completion_done(&can->flush_comp))
453 		kvaser_pciefd_start_controller_flush(can);
454 
455 	if (!wait_for_completion_timeout(&can->flush_comp,
456 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
457 		netdev_err(can->can.dev, "Timeout during bus on flush\n");
458 		return -ETIMEDOUT;
459 	}
460 
461 	spin_lock_irqsave(&can->lock, irq);
462 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
463 	iowrite32(GENMASK(31, 0), can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
464 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
465 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
466 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
467 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
468 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
469 	spin_unlock_irqrestore(&can->lock, irq);
470 
471 	if (!wait_for_completion_timeout(&can->start_comp,
472 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
473 		netdev_err(can->can.dev, "Timeout during bus on reset\n");
474 		return -ETIMEDOUT;
475 	}
476 	/* Reset interrupt handling */
477 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
478 	iowrite32(GENMASK(31, 0), can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
479 
480 	kvaser_pciefd_set_tx_irq(can);
481 	kvaser_pciefd_setup_controller(can);
482 	can->can.state = CAN_STATE_ERROR_ACTIVE;
483 	netif_wake_queue(can->can.dev);
484 	can->bec.txerr = 0;
485 	can->bec.rxerr = 0;
486 	can->err_rep_cnt = 0;
487 
488 	return 0;
489 }
490 
491 static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
492 {
493 	u8 top;
494 	u32 pwm_ctrl;
495 	unsigned long irq;
496 
497 	spin_lock_irqsave(&can->lock, irq);
498 	pwm_ctrl = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
499 	top = FIELD_GET(KVASER_PCIEFD_KCAN_PWM_TOP_MASK, pwm_ctrl);
500 	/* Set duty cycle to zero */
501 	pwm_ctrl |= FIELD_PREP(KVASER_PCIEFD_KCAN_PWM_TRIGGER_MASK, top);
502 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
503 	spin_unlock_irqrestore(&can->lock, irq);
504 }
505 
506 static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
507 {
508 	int top, trigger;
509 	u32 pwm_ctrl;
510 	unsigned long irq;
511 
512 	kvaser_pciefd_pwm_stop(can);
513 	spin_lock_irqsave(&can->lock, irq);
514 	/* Set frequency to 500 KHz */
515 	top = can->kv_pcie->bus_freq / (2 * 500000) - 1;
516 
517 	pwm_ctrl = FIELD_PREP(KVASER_PCIEFD_KCAN_PWM_TRIGGER_MASK, top);
518 	pwm_ctrl |= FIELD_PREP(KVASER_PCIEFD_KCAN_PWM_TOP_MASK, top);
519 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
520 
521 	/* Set duty cycle to 95 */
522 	trigger = (100 * top - 95 * (top + 1) + 50) / 100;
523 	pwm_ctrl = FIELD_PREP(KVASER_PCIEFD_KCAN_PWM_TRIGGER_MASK, trigger);
524 	pwm_ctrl |= FIELD_PREP(KVASER_PCIEFD_KCAN_PWM_TOP_MASK, top);
525 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
526 	spin_unlock_irqrestore(&can->lock, irq);
527 }
528 
529 static int kvaser_pciefd_open(struct net_device *netdev)
530 {
531 	int err;
532 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
533 
534 	err = open_candev(netdev);
535 	if (err)
536 		return err;
537 
538 	err = kvaser_pciefd_bus_on(can);
539 	if (err) {
540 		close_candev(netdev);
541 		return err;
542 	}
543 
544 	return 0;
545 }
546 
547 static int kvaser_pciefd_stop(struct net_device *netdev)
548 {
549 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
550 	int ret = 0;
551 
552 	/* Don't interrupt ongoing flush */
553 	if (!completion_done(&can->flush_comp))
554 		kvaser_pciefd_start_controller_flush(can);
555 
556 	if (!wait_for_completion_timeout(&can->flush_comp,
557 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
558 		netdev_err(can->can.dev, "Timeout during stop\n");
559 		ret = -ETIMEDOUT;
560 	} else {
561 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
562 		del_timer(&can->bec_poll_timer);
563 	}
564 	can->can.state = CAN_STATE_STOPPED;
565 	close_candev(netdev);
566 
567 	return ret;
568 }
569 
570 static int kvaser_pciefd_prepare_tx_packet(struct kvaser_pciefd_tx_packet *p,
571 					   struct kvaser_pciefd_can *can,
572 					   struct sk_buff *skb)
573 {
574 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
575 	int packet_size;
576 	int seq = can->echo_idx;
577 
578 	memset(p, 0, sizeof(*p));
579 	if (can->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
580 		p->header[1] |= KVASER_PCIEFD_TPACKET_SMS;
581 
582 	if (cf->can_id & CAN_RTR_FLAG)
583 		p->header[0] |= KVASER_PCIEFD_RPACKET_RTR;
584 
585 	if (cf->can_id & CAN_EFF_FLAG)
586 		p->header[0] |= KVASER_PCIEFD_RPACKET_IDE;
587 
588 	p->header[0] |= FIELD_PREP(KVASER_PCIEFD_RPACKET_ID_MASK, cf->can_id);
589 	p->header[1] |= KVASER_PCIEFD_TPACKET_AREQ;
590 
591 	if (can_is_canfd_skb(skb)) {
592 		p->header[1] |= FIELD_PREP(KVASER_PCIEFD_RPACKET_DLC_MASK,
593 					   can_fd_len2dlc(cf->len));
594 		p->header[1] |= KVASER_PCIEFD_RPACKET_FDF;
595 		if (cf->flags & CANFD_BRS)
596 			p->header[1] |= KVASER_PCIEFD_RPACKET_BRS;
597 		if (cf->flags & CANFD_ESI)
598 			p->header[1] |= KVASER_PCIEFD_RPACKET_ESI;
599 	} else {
600 		p->header[1] |=
601 			FIELD_PREP(KVASER_PCIEFD_RPACKET_DLC_MASK,
602 				   can_get_cc_dlc((struct can_frame *)cf, can->can.ctrlmode));
603 	}
604 
605 	p->header[1] |= FIELD_PREP(KVASER_PCIEFD_PACKET_SEQ_MASK, seq);
606 
607 	packet_size = cf->len;
608 	memcpy(p->data, cf->data, packet_size);
609 
610 	return DIV_ROUND_UP(packet_size, 4);
611 }
612 
613 static netdev_tx_t kvaser_pciefd_start_xmit(struct sk_buff *skb,
614 					    struct net_device *netdev)
615 {
616 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
617 	unsigned long irq_flags;
618 	struct kvaser_pciefd_tx_packet packet;
619 	int nr_words;
620 	u8 count;
621 
622 	if (can_dev_dropped_skb(netdev, skb))
623 		return NETDEV_TX_OK;
624 
625 	nr_words = kvaser_pciefd_prepare_tx_packet(&packet, can, skb);
626 
627 	spin_lock_irqsave(&can->echo_lock, irq_flags);
628 	/* Prepare and save echo skb in internal slot */
629 	can_put_echo_skb(skb, netdev, can->echo_idx, 0);
630 
631 	/* Move echo index to the next slot */
632 	can->echo_idx = (can->echo_idx + 1) % can->can.echo_skb_max;
633 
634 	/* Write header to fifo */
635 	iowrite32(packet.header[0],
636 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
637 	iowrite32(packet.header[1],
638 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
639 
640 	if (nr_words) {
641 		u32 data_last = ((u32 *)packet.data)[nr_words - 1];
642 
643 		/* Write data to fifo, except last word */
644 		iowrite32_rep(can->reg_base +
645 			      KVASER_PCIEFD_KCAN_FIFO_REG, packet.data,
646 			      nr_words - 1);
647 		/* Write last word to end of fifo */
648 		__raw_writel(data_last, can->reg_base +
649 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
650 	} else {
651 		/* Complete write to fifo */
652 		__raw_writel(0, can->reg_base +
653 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
654 	}
655 
656 	count = FIELD_GET(KVASER_PCIEFD_KCAN_TX_NR_PACKETS_CURRENT_MASK,
657 			  ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NR_PACKETS_REG));
658 	/* No room for a new message, stop the queue until at least one
659 	 * successful transmit
660 	 */
661 	if (count >= can->can.echo_skb_max || can->can.echo_skb[can->echo_idx])
662 		netif_stop_queue(netdev);
663 	spin_unlock_irqrestore(&can->echo_lock, irq_flags);
664 
665 	return NETDEV_TX_OK;
666 }
667 
668 static int kvaser_pciefd_set_bittiming(struct kvaser_pciefd_can *can, bool data)
669 {
670 	u32 mode, test, btrn;
671 	unsigned long irq_flags;
672 	int ret;
673 	struct can_bittiming *bt;
674 
675 	if (data)
676 		bt = &can->can.data_bittiming;
677 	else
678 		bt = &can->can.bittiming;
679 
680 	btrn = FIELD_PREP(KVASER_PCIEFD_KCAN_BTRN_TSEG2_MASK, bt->phase_seg2 - 1) |
681 	       FIELD_PREP(KVASER_PCIEFD_KCAN_BTRN_TSEG1_MASK, bt->prop_seg + bt->phase_seg1 - 1) |
682 	       FIELD_PREP(KVASER_PCIEFD_KCAN_BTRN_SJW_MASK, bt->sjw - 1) |
683 	       FIELD_PREP(KVASER_PCIEFD_KCAN_BTRN_BRP_MASK, bt->brp - 1);
684 
685 	spin_lock_irqsave(&can->lock, irq_flags);
686 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
687 	/* Put the circuit in reset mode */
688 	iowrite32(mode | KVASER_PCIEFD_KCAN_MODE_RM,
689 		  can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
690 
691 	/* Can only set bittiming if in reset mode */
692 	ret = readl_poll_timeout(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG,
693 				 test, test & KVASER_PCIEFD_KCAN_MODE_RM, 0, 10);
694 	if (ret) {
695 		spin_unlock_irqrestore(&can->lock, irq_flags);
696 		return -EBUSY;
697 	}
698 
699 	if (data)
700 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRD_REG);
701 	else
702 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRN_REG);
703 	/* Restore previous reset mode status */
704 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
705 	spin_unlock_irqrestore(&can->lock, irq_flags);
706 
707 	return 0;
708 }
709 
710 static int kvaser_pciefd_set_nominal_bittiming(struct net_device *ndev)
711 {
712 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), false);
713 }
714 
715 static int kvaser_pciefd_set_data_bittiming(struct net_device *ndev)
716 {
717 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), true);
718 }
719 
720 static int kvaser_pciefd_set_mode(struct net_device *ndev, enum can_mode mode)
721 {
722 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
723 	int ret = 0;
724 
725 	switch (mode) {
726 	case CAN_MODE_START:
727 		if (!can->can.restart_ms)
728 			ret = kvaser_pciefd_bus_on(can);
729 		break;
730 	default:
731 		return -EOPNOTSUPP;
732 	}
733 
734 	return ret;
735 }
736 
737 static int kvaser_pciefd_get_berr_counter(const struct net_device *ndev,
738 					  struct can_berr_counter *bec)
739 {
740 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
741 
742 	bec->rxerr = can->bec.rxerr;
743 	bec->txerr = can->bec.txerr;
744 
745 	return 0;
746 }
747 
748 static void kvaser_pciefd_bec_poll_timer(struct timer_list *data)
749 {
750 	struct kvaser_pciefd_can *can = from_timer(can, data, bec_poll_timer);
751 
752 	kvaser_pciefd_enable_err_gen(can);
753 	kvaser_pciefd_request_status(can);
754 	can->err_rep_cnt = 0;
755 }
756 
757 static const struct net_device_ops kvaser_pciefd_netdev_ops = {
758 	.ndo_open = kvaser_pciefd_open,
759 	.ndo_stop = kvaser_pciefd_stop,
760 	.ndo_eth_ioctl = can_eth_ioctl_hwts,
761 	.ndo_start_xmit = kvaser_pciefd_start_xmit,
762 	.ndo_change_mtu = can_change_mtu,
763 };
764 
765 static const struct ethtool_ops kvaser_pciefd_ethtool_ops = {
766 	.get_ts_info = can_ethtool_op_get_ts_info_hwts,
767 };
768 
769 static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
770 {
771 	int i;
772 
773 	for (i = 0; i < pcie->nr_channels; i++) {
774 		struct net_device *netdev;
775 		struct kvaser_pciefd_can *can;
776 		u32 status, tx_nr_packets_max;
777 
778 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
779 				      KVASER_PCIEFD_CAN_TX_MAX_COUNT);
780 		if (!netdev)
781 			return -ENOMEM;
782 
783 		can = netdev_priv(netdev);
784 		netdev->netdev_ops = &kvaser_pciefd_netdev_ops;
785 		netdev->ethtool_ops = &kvaser_pciefd_ethtool_ops;
786 		can->reg_base = pcie->reg_base + KVASER_PCIEFD_KCAN0_BASE +
787 				i * KVASER_PCIEFD_KCAN_BASE_OFFSET;
788 		can->kv_pcie = pcie;
789 		can->cmd_seq = 0;
790 		can->err_rep_cnt = 0;
791 		can->bec.txerr = 0;
792 		can->bec.rxerr = 0;
793 
794 		init_completion(&can->start_comp);
795 		init_completion(&can->flush_comp);
796 		timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer, 0);
797 
798 		/* Disable Bus load reporting */
799 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_BUS_LOAD_REG);
800 
801 		tx_nr_packets_max =
802 			FIELD_GET(KVASER_PCIEFD_KCAN_TX_NR_PACKETS_MAX_MASK,
803 				  ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NR_PACKETS_REG));
804 
805 		can->can.clock.freq = pcie->freq;
806 		can->can.echo_skb_max = min(KVASER_PCIEFD_CAN_TX_MAX_COUNT, tx_nr_packets_max - 1);
807 		can->echo_idx = 0;
808 		spin_lock_init(&can->echo_lock);
809 		spin_lock_init(&can->lock);
810 
811 		can->can.bittiming_const = &kvaser_pciefd_bittiming_const;
812 		can->can.data_bittiming_const = &kvaser_pciefd_bittiming_const;
813 		can->can.do_set_bittiming = kvaser_pciefd_set_nominal_bittiming;
814 		can->can.do_set_data_bittiming = kvaser_pciefd_set_data_bittiming;
815 		can->can.do_set_mode = kvaser_pciefd_set_mode;
816 		can->can.do_get_berr_counter = kvaser_pciefd_get_berr_counter;
817 		can->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
818 					      CAN_CTRLMODE_FD |
819 					      CAN_CTRLMODE_FD_NON_ISO |
820 					      CAN_CTRLMODE_CC_LEN8_DLC;
821 
822 		status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
823 		if (!(status & KVASER_PCIEFD_KCAN_STAT_FD)) {
824 			dev_err(&pcie->pci->dev,
825 				"CAN FD not supported as expected %d\n", i);
826 
827 			free_candev(netdev);
828 			return -ENODEV;
829 		}
830 
831 		if (status & KVASER_PCIEFD_KCAN_STAT_CAP)
832 			can->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
833 
834 		netdev->flags |= IFF_ECHO;
835 		SET_NETDEV_DEV(netdev, &pcie->pci->dev);
836 
837 		iowrite32(GENMASK(31, 0), can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
838 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
839 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
840 
841 		pcie->can[i] = can;
842 		kvaser_pciefd_pwm_start(can);
843 	}
844 
845 	return 0;
846 }
847 
848 static int kvaser_pciefd_reg_candev(struct kvaser_pciefd *pcie)
849 {
850 	int i;
851 
852 	for (i = 0; i < pcie->nr_channels; i++) {
853 		int err = register_candev(pcie->can[i]->can.dev);
854 
855 		if (err) {
856 			int j;
857 
858 			/* Unregister all successfully registered devices. */
859 			for (j = 0; j < i; j++)
860 				unregister_candev(pcie->can[j]->can.dev);
861 			return err;
862 		}
863 	}
864 
865 	return 0;
866 }
867 
868 static void kvaser_pciefd_write_dma_map(struct kvaser_pciefd *pcie,
869 					dma_addr_t addr, int offset)
870 {
871 	u32 word1, word2;
872 
873 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
874 	word1 = addr | KVASER_PCIEFD_64BIT_DMA_BIT;
875 	word2 = addr >> 32;
876 #else
877 	word1 = addr;
878 	word2 = 0;
879 #endif
880 	iowrite32(word1, pcie->reg_base + offset);
881 	iowrite32(word2, pcie->reg_base + offset + 4);
882 }
883 
884 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
885 {
886 	int i;
887 	u32 srb_status;
888 	u32 srb_packet_count;
889 	dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
890 
891 	/* Disable the DMA */
892 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
893 	for (i = 0; i < KVASER_PCIEFD_DMA_COUNT; i++) {
894 		unsigned int offset = KVASER_PCIEFD_DMA_MAP_BASE + 8 * i;
895 
896 		pcie->dma_data[i] = dmam_alloc_coherent(&pcie->pci->dev,
897 							KVASER_PCIEFD_DMA_SIZE,
898 							&dma_addr[i],
899 							GFP_KERNEL);
900 
901 		if (!pcie->dma_data[i] || !dma_addr[i]) {
902 			dev_err(&pcie->pci->dev, "Rx dma_alloc(%u) failure\n",
903 				KVASER_PCIEFD_DMA_SIZE);
904 			return -ENOMEM;
905 		}
906 		kvaser_pciefd_write_dma_map(pcie, dma_addr[i], offset);
907 	}
908 
909 	/* Reset Rx FIFO, and both DMA buffers */
910 	iowrite32(KVASER_PCIEFD_SRB_CMD_FOR | KVASER_PCIEFD_SRB_CMD_RDB0 |
911 		  KVASER_PCIEFD_SRB_CMD_RDB1,
912 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
913 	/* Empty Rx FIFO */
914 	srb_packet_count =
915 		FIELD_GET(KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK,
916 			  ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG));
917 	while (srb_packet_count) {
918 		/* Drop current packet in FIFO */
919 		ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_FIFO_LAST_REG);
920 		srb_packet_count--;
921 	}
922 
923 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
924 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
925 		dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
926 		return -EIO;
927 	}
928 
929 	/* Enable the DMA */
930 	iowrite32(KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE,
931 		  pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
932 
933 	return 0;
934 }
935 
936 static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
937 {
938 	u32 version, srb_status, build;
939 
940 	version = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_VERSION_REG);
941 	pcie->nr_channels = min(KVASER_PCIEFD_MAX_CAN_CHANNELS,
942 				FIELD_GET(KVASER_PCIEFD_SYSID_VERSION_NR_CHAN_MASK, version));
943 
944 	build = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_BUILD_REG);
945 	dev_dbg(&pcie->pci->dev, "Version %lu.%lu.%lu\n",
946 		FIELD_GET(KVASER_PCIEFD_SYSID_VERSION_MAJOR_MASK, version),
947 		FIELD_GET(KVASER_PCIEFD_SYSID_VERSION_MINOR_MASK, version),
948 		FIELD_GET(KVASER_PCIEFD_SYSID_BUILD_SEQ_MASK, build));
949 
950 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
951 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DMA)) {
952 		dev_err(&pcie->pci->dev, "Hardware without DMA is not supported\n");
953 		return -ENODEV;
954 	}
955 
956 	pcie->bus_freq = ioread32(pcie->reg_base +
957 				  KVASER_PCIEFD_SYSID_BUSFREQ_REG);
958 	pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
959 	pcie->freq_to_ticks_div = pcie->freq / 1000000;
960 	if (pcie->freq_to_ticks_div == 0)
961 		pcie->freq_to_ticks_div = 1;
962 	/* Turn off all loopback functionality */
963 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_LOOP_REG);
964 
965 	return 0;
966 }
967 
968 static int kvaser_pciefd_handle_data_packet(struct kvaser_pciefd *pcie,
969 					    struct kvaser_pciefd_rx_packet *p,
970 					    __le32 *data)
971 {
972 	struct sk_buff *skb;
973 	struct canfd_frame *cf;
974 	struct can_priv *priv;
975 	u8 ch_id = FIELD_GET(KVASER_PCIEFD_PACKET_CHID_MASK, p->header[1]);
976 	u8 dlc;
977 
978 	if (ch_id >= pcie->nr_channels)
979 		return -EIO;
980 
981 	priv = &pcie->can[ch_id]->can;
982 	dlc = FIELD_GET(KVASER_PCIEFD_RPACKET_DLC_MASK, p->header[1]);
983 
984 	if (p->header[1] & KVASER_PCIEFD_RPACKET_FDF) {
985 		skb = alloc_canfd_skb(priv->dev, &cf);
986 		if (!skb) {
987 			priv->dev->stats.rx_dropped++;
988 			return -ENOMEM;
989 		}
990 
991 		cf->len = can_fd_dlc2len(dlc);
992 		if (p->header[1] & KVASER_PCIEFD_RPACKET_BRS)
993 			cf->flags |= CANFD_BRS;
994 		if (p->header[1] & KVASER_PCIEFD_RPACKET_ESI)
995 			cf->flags |= CANFD_ESI;
996 	} else {
997 		skb = alloc_can_skb(priv->dev, (struct can_frame **)&cf);
998 		if (!skb) {
999 			priv->dev->stats.rx_dropped++;
1000 			return -ENOMEM;
1001 		}
1002 		can_frame_set_cc_len((struct can_frame *)cf, dlc, priv->ctrlmode);
1003 	}
1004 
1005 	cf->can_id = FIELD_GET(KVASER_PCIEFD_RPACKET_ID_MASK, p->header[0]);
1006 	if (p->header[0] & KVASER_PCIEFD_RPACKET_IDE)
1007 		cf->can_id |= CAN_EFF_FLAG;
1008 
1009 	if (p->header[0] & KVASER_PCIEFD_RPACKET_RTR) {
1010 		cf->can_id |= CAN_RTR_FLAG;
1011 	} else {
1012 		memcpy(cf->data, data, cf->len);
1013 		priv->dev->stats.rx_bytes += cf->len;
1014 	}
1015 	priv->dev->stats.rx_packets++;
1016 	kvaser_pciefd_set_skb_timestamp(pcie, skb, p->timestamp);
1017 
1018 	return netif_rx(skb);
1019 }
1020 
1021 static void kvaser_pciefd_change_state(struct kvaser_pciefd_can *can,
1022 				       struct can_frame *cf,
1023 				       enum can_state new_state,
1024 				       enum can_state tx_state,
1025 				       enum can_state rx_state)
1026 {
1027 	can_change_state(can->can.dev, cf, tx_state, rx_state);
1028 
1029 	if (new_state == CAN_STATE_BUS_OFF) {
1030 		struct net_device *ndev = can->can.dev;
1031 		unsigned long irq_flags;
1032 
1033 		spin_lock_irqsave(&can->lock, irq_flags);
1034 		netif_stop_queue(can->can.dev);
1035 		spin_unlock_irqrestore(&can->lock, irq_flags);
1036 		/* Prevent CAN controller from auto recover from bus off */
1037 		if (!can->can.restart_ms) {
1038 			kvaser_pciefd_start_controller_flush(can);
1039 			can_bus_off(ndev);
1040 		}
1041 	}
1042 }
1043 
1044 static void kvaser_pciefd_packet_to_state(struct kvaser_pciefd_rx_packet *p,
1045 					  struct can_berr_counter *bec,
1046 					  enum can_state *new_state,
1047 					  enum can_state *tx_state,
1048 					  enum can_state *rx_state)
1049 {
1050 	if (p->header[0] & KVASER_PCIEFD_SPACK_BOFF ||
1051 	    p->header[0] & KVASER_PCIEFD_SPACK_IRM)
1052 		*new_state = CAN_STATE_BUS_OFF;
1053 	else if (bec->txerr >= 255 || bec->rxerr >= 255)
1054 		*new_state = CAN_STATE_BUS_OFF;
1055 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EPLR)
1056 		*new_state = CAN_STATE_ERROR_PASSIVE;
1057 	else if (bec->txerr >= 128 || bec->rxerr >= 128)
1058 		*new_state = CAN_STATE_ERROR_PASSIVE;
1059 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EWLR)
1060 		*new_state = CAN_STATE_ERROR_WARNING;
1061 	else if (bec->txerr >= 96 || bec->rxerr >= 96)
1062 		*new_state = CAN_STATE_ERROR_WARNING;
1063 	else
1064 		*new_state = CAN_STATE_ERROR_ACTIVE;
1065 
1066 	*tx_state = bec->txerr >= bec->rxerr ? *new_state : 0;
1067 	*rx_state = bec->txerr <= bec->rxerr ? *new_state : 0;
1068 }
1069 
1070 static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
1071 					struct kvaser_pciefd_rx_packet *p)
1072 {
1073 	struct can_berr_counter bec;
1074 	enum can_state old_state, new_state, tx_state, rx_state;
1075 	struct net_device *ndev = can->can.dev;
1076 	struct sk_buff *skb;
1077 	struct can_frame *cf = NULL;
1078 
1079 	old_state = can->can.state;
1080 
1081 	bec.txerr = FIELD_GET(KVASER_PCIEFD_SPACK_TXERR_MASK, p->header[0]);
1082 	bec.rxerr = FIELD_GET(KVASER_PCIEFD_SPACK_RXERR_MASK, p->header[0]);
1083 
1084 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state, &rx_state);
1085 	skb = alloc_can_err_skb(ndev, &cf);
1086 	if (new_state != old_state) {
1087 		kvaser_pciefd_change_state(can, cf, new_state, tx_state, rx_state);
1088 		if (old_state == CAN_STATE_BUS_OFF &&
1089 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1090 		    can->can.restart_ms) {
1091 			can->can.can_stats.restarts++;
1092 			if (skb)
1093 				cf->can_id |= CAN_ERR_RESTARTED;
1094 		}
1095 	}
1096 
1097 	can->err_rep_cnt++;
1098 	can->can.can_stats.bus_error++;
1099 	if (p->header[1] & KVASER_PCIEFD_EPACK_DIR_TX)
1100 		ndev->stats.tx_errors++;
1101 	else
1102 		ndev->stats.rx_errors++;
1103 
1104 	can->bec.txerr = bec.txerr;
1105 	can->bec.rxerr = bec.rxerr;
1106 
1107 	if (!skb) {
1108 		ndev->stats.rx_dropped++;
1109 		return -ENOMEM;
1110 	}
1111 
1112 	kvaser_pciefd_set_skb_timestamp(can->kv_pcie, skb, p->timestamp);
1113 	cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT;
1114 	cf->data[6] = bec.txerr;
1115 	cf->data[7] = bec.rxerr;
1116 
1117 	netif_rx(skb);
1118 
1119 	return 0;
1120 }
1121 
1122 static int kvaser_pciefd_handle_error_packet(struct kvaser_pciefd *pcie,
1123 					     struct kvaser_pciefd_rx_packet *p)
1124 {
1125 	struct kvaser_pciefd_can *can;
1126 	u8 ch_id = FIELD_GET(KVASER_PCIEFD_PACKET_CHID_MASK, p->header[1]);
1127 
1128 	if (ch_id >= pcie->nr_channels)
1129 		return -EIO;
1130 
1131 	can = pcie->can[ch_id];
1132 	kvaser_pciefd_rx_error_frame(can, p);
1133 	if (can->err_rep_cnt >= KVASER_PCIEFD_MAX_ERR_REP)
1134 		/* Do not report more errors, until bec_poll_timer expires */
1135 		kvaser_pciefd_disable_err_gen(can);
1136 	/* Start polling the error counters */
1137 	mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1138 
1139 	return 0;
1140 }
1141 
1142 static int kvaser_pciefd_handle_status_resp(struct kvaser_pciefd_can *can,
1143 					    struct kvaser_pciefd_rx_packet *p)
1144 {
1145 	struct can_berr_counter bec;
1146 	enum can_state old_state, new_state, tx_state, rx_state;
1147 
1148 	old_state = can->can.state;
1149 
1150 	bec.txerr = FIELD_GET(KVASER_PCIEFD_SPACK_TXERR_MASK, p->header[0]);
1151 	bec.rxerr = FIELD_GET(KVASER_PCIEFD_SPACK_RXERR_MASK, p->header[0]);
1152 
1153 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state, &rx_state);
1154 	if (new_state != old_state) {
1155 		struct net_device *ndev = can->can.dev;
1156 		struct sk_buff *skb;
1157 		struct can_frame *cf;
1158 
1159 		skb = alloc_can_err_skb(ndev, &cf);
1160 		if (!skb) {
1161 			ndev->stats.rx_dropped++;
1162 			return -ENOMEM;
1163 		}
1164 
1165 		kvaser_pciefd_change_state(can, cf, new_state, tx_state, rx_state);
1166 		if (old_state == CAN_STATE_BUS_OFF &&
1167 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1168 		    can->can.restart_ms) {
1169 			can->can.can_stats.restarts++;
1170 			cf->can_id |= CAN_ERR_RESTARTED;
1171 		}
1172 
1173 		kvaser_pciefd_set_skb_timestamp(can->kv_pcie, skb, p->timestamp);
1174 
1175 		cf->data[6] = bec.txerr;
1176 		cf->data[7] = bec.rxerr;
1177 
1178 		netif_rx(skb);
1179 	}
1180 	can->bec.txerr = bec.txerr;
1181 	can->bec.rxerr = bec.rxerr;
1182 	/* Check if we need to poll the error counters */
1183 	if (bec.txerr || bec.rxerr)
1184 		mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1185 
1186 	return 0;
1187 }
1188 
1189 static int kvaser_pciefd_handle_status_packet(struct kvaser_pciefd *pcie,
1190 					      struct kvaser_pciefd_rx_packet *p)
1191 {
1192 	struct kvaser_pciefd_can *can;
1193 	u8 cmdseq;
1194 	u32 status;
1195 	u8 ch_id = FIELD_GET(KVASER_PCIEFD_PACKET_CHID_MASK, p->header[1]);
1196 
1197 	if (ch_id >= pcie->nr_channels)
1198 		return -EIO;
1199 
1200 	can = pcie->can[ch_id];
1201 
1202 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1203 	cmdseq = FIELD_GET(KVASER_PCIEFD_KCAN_STAT_SEQNO_MASK, status);
1204 
1205 	/* Reset done, start abort and flush */
1206 	if (p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1207 	    p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1208 	    p->header[1] & KVASER_PCIEFD_SPACK_AUTO &&
1209 	    cmdseq == FIELD_GET(KVASER_PCIEFD_PACKET_SEQ_MASK, p->header[1]) &&
1210 	    status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1211 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1212 			  can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1213 		kvaser_pciefd_abort_flush_reset(can);
1214 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET &&
1215 		   p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1216 		   cmdseq == FIELD_GET(KVASER_PCIEFD_PACKET_SEQ_MASK, p->header[1]) &&
1217 		   status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1218 		/* Reset detected, send end of flush if no packet are in FIFO */
1219 		u8 count;
1220 
1221 		count = FIELD_GET(KVASER_PCIEFD_KCAN_TX_NR_PACKETS_CURRENT_MASK,
1222 				  ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NR_PACKETS_REG));
1223 		if (!count)
1224 			iowrite32(FIELD_PREP(KVASER_PCIEFD_KCAN_CTRL_TYPE_MASK,
1225 					     KVASER_PCIEFD_KCAN_CTRL_TYPE_EFLUSH),
1226 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1227 	} else if (!(p->header[1] & KVASER_PCIEFD_SPACK_AUTO) &&
1228 		   cmdseq == FIELD_GET(KVASER_PCIEFD_PACKET_SEQ_MASK, p->header[1])) {
1229 		/* Response to status request received */
1230 		kvaser_pciefd_handle_status_resp(can, p);
1231 		if (can->can.state != CAN_STATE_BUS_OFF &&
1232 		    can->can.state != CAN_STATE_ERROR_ACTIVE) {
1233 			mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1234 		}
1235 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1236 		   !(status & KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MASK)) {
1237 		/* Reset to bus on detected */
1238 		if (!completion_done(&can->start_comp))
1239 			complete(&can->start_comp);
1240 	}
1241 
1242 	return 0;
1243 }
1244 
1245 static void kvaser_pciefd_handle_nack_packet(struct kvaser_pciefd_can *can,
1246 					     struct kvaser_pciefd_rx_packet *p)
1247 {
1248 	struct sk_buff *skb;
1249 	struct can_frame *cf;
1250 
1251 	skb = alloc_can_err_skb(can->can.dev, &cf);
1252 	can->can.dev->stats.tx_errors++;
1253 	if (p->header[0] & KVASER_PCIEFD_APACKET_ABL) {
1254 		if (skb)
1255 			cf->can_id |= CAN_ERR_LOSTARB;
1256 		can->can.can_stats.arbitration_lost++;
1257 	} else if (skb) {
1258 		cf->can_id |= CAN_ERR_ACK;
1259 	}
1260 
1261 	if (skb) {
1262 		cf->can_id |= CAN_ERR_BUSERROR;
1263 		kvaser_pciefd_set_skb_timestamp(can->kv_pcie, skb, p->timestamp);
1264 		netif_rx(skb);
1265 	} else {
1266 		can->can.dev->stats.rx_dropped++;
1267 		netdev_warn(can->can.dev, "No memory left for err_skb\n");
1268 	}
1269 }
1270 
1271 static int kvaser_pciefd_handle_ack_packet(struct kvaser_pciefd *pcie,
1272 					   struct kvaser_pciefd_rx_packet *p)
1273 {
1274 	struct kvaser_pciefd_can *can;
1275 	bool one_shot_fail = false;
1276 	u8 ch_id = FIELD_GET(KVASER_PCIEFD_PACKET_CHID_MASK, p->header[1]);
1277 
1278 	if (ch_id >= pcie->nr_channels)
1279 		return -EIO;
1280 
1281 	can = pcie->can[ch_id];
1282 	/* Ignore control packet ACK */
1283 	if (p->header[0] & KVASER_PCIEFD_APACKET_CT)
1284 		return 0;
1285 
1286 	if (p->header[0] & KVASER_PCIEFD_APACKET_NACK) {
1287 		kvaser_pciefd_handle_nack_packet(can, p);
1288 		one_shot_fail = true;
1289 	}
1290 
1291 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1292 		netdev_dbg(can->can.dev, "Packet was flushed\n");
1293 	} else {
1294 		int echo_idx = FIELD_GET(KVASER_PCIEFD_PACKET_SEQ_MASK, p->header[0]);
1295 		int len;
1296 		u8 count;
1297 		struct sk_buff *skb;
1298 
1299 		skb = can->can.echo_skb[echo_idx];
1300 		if (skb)
1301 			kvaser_pciefd_set_skb_timestamp(pcie, skb, p->timestamp);
1302 		len = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1303 		count = FIELD_GET(KVASER_PCIEFD_KCAN_TX_NR_PACKETS_CURRENT_MASK,
1304 				  ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NR_PACKETS_REG));
1305 
1306 		if (count < can->can.echo_skb_max && netif_queue_stopped(can->can.dev))
1307 			netif_wake_queue(can->can.dev);
1308 
1309 		if (!one_shot_fail) {
1310 			can->can.dev->stats.tx_bytes += len;
1311 			can->can.dev->stats.tx_packets++;
1312 		}
1313 	}
1314 
1315 	return 0;
1316 }
1317 
1318 static int kvaser_pciefd_handle_eflush_packet(struct kvaser_pciefd *pcie,
1319 					      struct kvaser_pciefd_rx_packet *p)
1320 {
1321 	struct kvaser_pciefd_can *can;
1322 	u8 ch_id = FIELD_GET(KVASER_PCIEFD_PACKET_CHID_MASK, p->header[1]);
1323 
1324 	if (ch_id >= pcie->nr_channels)
1325 		return -EIO;
1326 
1327 	can = pcie->can[ch_id];
1328 
1329 	if (!completion_done(&can->flush_comp))
1330 		complete(&can->flush_comp);
1331 
1332 	return 0;
1333 }
1334 
1335 static int kvaser_pciefd_read_packet(struct kvaser_pciefd *pcie, int *start_pos,
1336 				     int dma_buf)
1337 {
1338 	__le32 *buffer = pcie->dma_data[dma_buf];
1339 	__le64 timestamp;
1340 	struct kvaser_pciefd_rx_packet packet;
1341 	struct kvaser_pciefd_rx_packet *p = &packet;
1342 	u8 type;
1343 	int pos = *start_pos;
1344 	int size;
1345 	int ret = 0;
1346 
1347 	size = le32_to_cpu(buffer[pos++]);
1348 	if (!size) {
1349 		*start_pos = 0;
1350 		return 0;
1351 	}
1352 
1353 	p->header[0] = le32_to_cpu(buffer[pos++]);
1354 	p->header[1] = le32_to_cpu(buffer[pos++]);
1355 
1356 	/* Read 64-bit timestamp */
1357 	memcpy(&timestamp, &buffer[pos], sizeof(__le64));
1358 	pos += 2;
1359 	p->timestamp = le64_to_cpu(timestamp);
1360 
1361 	type = FIELD_GET(KVASER_PCIEFD_PACKET_TYPE_MASK, p->header[1]);
1362 	switch (type) {
1363 	case KVASER_PCIEFD_PACK_TYPE_DATA:
1364 		ret = kvaser_pciefd_handle_data_packet(pcie, p, &buffer[pos]);
1365 		if (!(p->header[0] & KVASER_PCIEFD_RPACKET_RTR)) {
1366 			u8 data_len;
1367 
1368 			data_len = can_fd_dlc2len(FIELD_GET(KVASER_PCIEFD_RPACKET_DLC_MASK,
1369 							    p->header[1]));
1370 			pos += DIV_ROUND_UP(data_len, 4);
1371 		}
1372 		break;
1373 
1374 	case KVASER_PCIEFD_PACK_TYPE_ACK:
1375 		ret = kvaser_pciefd_handle_ack_packet(pcie, p);
1376 		break;
1377 
1378 	case KVASER_PCIEFD_PACK_TYPE_STATUS:
1379 		ret = kvaser_pciefd_handle_status_packet(pcie, p);
1380 		break;
1381 
1382 	case KVASER_PCIEFD_PACK_TYPE_ERROR:
1383 		ret = kvaser_pciefd_handle_error_packet(pcie, p);
1384 		break;
1385 
1386 	case KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK:
1387 		ret = kvaser_pciefd_handle_eflush_packet(pcie, p);
1388 		break;
1389 
1390 	case KVASER_PCIEFD_PACK_TYPE_ACK_DATA:
1391 	case KVASER_PCIEFD_PACK_TYPE_BUS_LOAD:
1392 	case KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK:
1393 	case KVASER_PCIEFD_PACK_TYPE_TXRQ:
1394 		dev_info(&pcie->pci->dev,
1395 			 "Received unexpected packet type 0x%08X\n", type);
1396 		break;
1397 
1398 	default:
1399 		dev_err(&pcie->pci->dev, "Unknown packet type 0x%08X\n", type);
1400 		ret = -EIO;
1401 		break;
1402 	}
1403 
1404 	if (ret)
1405 		return ret;
1406 
1407 	/* Position does not point to the end of the package,
1408 	 * corrupted packet size?
1409 	 */
1410 	if ((*start_pos + size) != pos)
1411 		return -EIO;
1412 
1413 	/* Point to the next packet header, if any */
1414 	*start_pos = pos;
1415 
1416 	return ret;
1417 }
1418 
1419 static int kvaser_pciefd_read_buffer(struct kvaser_pciefd *pcie, int dma_buf)
1420 {
1421 	int pos = 0;
1422 	int res = 0;
1423 
1424 	do {
1425 		res = kvaser_pciefd_read_packet(pcie, &pos, dma_buf);
1426 	} while (!res && pos > 0 && pos < KVASER_PCIEFD_DMA_SIZE);
1427 
1428 	return res;
1429 }
1430 
1431 static void kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
1432 {
1433 	u32 irq;
1434 
1435 	irq = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1436 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
1437 		kvaser_pciefd_read_buffer(pcie, 0);
1438 		/* Reset DMA buffer 0 */
1439 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1440 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1441 	}
1442 
1443 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
1444 		kvaser_pciefd_read_buffer(pcie, 1);
1445 		/* Reset DMA buffer 1 */
1446 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1447 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1448 	}
1449 
1450 	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
1451 	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
1452 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
1453 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
1454 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
1455 
1456 	iowrite32(irq, pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1457 }
1458 
1459 static void kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
1460 {
1461 	u32 irq = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1462 
1463 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF)
1464 		netdev_err(can->can.dev, "Tx FIFO overflow\n");
1465 
1466 	if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP)
1467 		netdev_err(can->can.dev,
1468 			   "Fail to change bittiming, when not in reset mode\n");
1469 
1470 	if (irq & KVASER_PCIEFD_KCAN_IRQ_FDIC)
1471 		netdev_err(can->can.dev, "CAN FD frame in CAN mode\n");
1472 
1473 	if (irq & KVASER_PCIEFD_KCAN_IRQ_ROF)
1474 		netdev_err(can->can.dev, "Rx FIFO overflow\n");
1475 
1476 	iowrite32(irq, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1477 }
1478 
1479 static irqreturn_t kvaser_pciefd_irq_handler(int irq, void *dev)
1480 {
1481 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
1482 	u32 board_irq;
1483 	int i;
1484 
1485 	board_irq = ioread32(pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1486 
1487 	if (!(board_irq & KVASER_PCIEFD_IRQ_ALL_MASK))
1488 		return IRQ_NONE;
1489 
1490 	if (board_irq & KVASER_PCIEFD_IRQ_SRB)
1491 		kvaser_pciefd_receive_irq(pcie);
1492 
1493 	for (i = 0; i < pcie->nr_channels; i++) {
1494 		if (!pcie->can[i]) {
1495 			dev_err(&pcie->pci->dev,
1496 				"IRQ mask points to unallocated controller\n");
1497 			break;
1498 		}
1499 
1500 		/* Check that mask matches channel (i) IRQ mask */
1501 		if (board_irq & (1 << i))
1502 			kvaser_pciefd_transmit_irq(pcie->can[i]);
1503 	}
1504 
1505 	return IRQ_HANDLED;
1506 }
1507 
1508 static void kvaser_pciefd_teardown_can_ctrls(struct kvaser_pciefd *pcie)
1509 {
1510 	int i;
1511 
1512 	for (i = 0; i < pcie->nr_channels; i++) {
1513 		struct kvaser_pciefd_can *can = pcie->can[i];
1514 
1515 		if (can) {
1516 			iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1517 			kvaser_pciefd_pwm_stop(can);
1518 			free_candev(can->can.dev);
1519 		}
1520 	}
1521 }
1522 
1523 static int kvaser_pciefd_probe(struct pci_dev *pdev,
1524 			       const struct pci_device_id *id)
1525 {
1526 	int err;
1527 	struct kvaser_pciefd *pcie;
1528 
1529 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
1530 	if (!pcie)
1531 		return -ENOMEM;
1532 
1533 	pci_set_drvdata(pdev, pcie);
1534 	pcie->pci = pdev;
1535 
1536 	err = pci_enable_device(pdev);
1537 	if (err)
1538 		return err;
1539 
1540 	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
1541 	if (err)
1542 		goto err_disable_pci;
1543 
1544 	pcie->reg_base = pci_iomap(pdev, 0, 0);
1545 	if (!pcie->reg_base) {
1546 		err = -ENOMEM;
1547 		goto err_release_regions;
1548 	}
1549 
1550 	err = kvaser_pciefd_setup_board(pcie);
1551 	if (err)
1552 		goto err_pci_iounmap;
1553 
1554 	err = kvaser_pciefd_setup_dma(pcie);
1555 	if (err)
1556 		goto err_pci_iounmap;
1557 
1558 	pci_set_master(pdev);
1559 
1560 	err = kvaser_pciefd_setup_can_ctrls(pcie);
1561 	if (err)
1562 		goto err_teardown_can_ctrls;
1563 
1564 	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
1565 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
1566 	if (err)
1567 		goto err_teardown_can_ctrls;
1568 
1569 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
1570 		  pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1571 
1572 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1 |
1573 		  KVASER_PCIEFD_SRB_IRQ_DOF0 | KVASER_PCIEFD_SRB_IRQ_DOF1 |
1574 		  KVASER_PCIEFD_SRB_IRQ_DUF0 | KVASER_PCIEFD_SRB_IRQ_DUF1,
1575 		  pcie->reg_base + KVASER_PCIEFD_SRB_IEN_REG);
1576 
1577 	/* Enable PCI interrupts */
1578 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MASK,
1579 		  pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1580 
1581 	/* Ready the DMA buffers */
1582 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1583 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1584 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1585 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1586 
1587 	err = kvaser_pciefd_reg_candev(pcie);
1588 	if (err)
1589 		goto err_free_irq;
1590 
1591 	return 0;
1592 
1593 err_free_irq:
1594 	/* Disable PCI interrupts */
1595 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1596 	free_irq(pcie->pci->irq, pcie);
1597 
1598 err_teardown_can_ctrls:
1599 	kvaser_pciefd_teardown_can_ctrls(pcie);
1600 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1601 	pci_clear_master(pdev);
1602 
1603 err_pci_iounmap:
1604 	pci_iounmap(pdev, pcie->reg_base);
1605 
1606 err_release_regions:
1607 	pci_release_regions(pdev);
1608 
1609 err_disable_pci:
1610 	pci_disable_device(pdev);
1611 
1612 	return err;
1613 }
1614 
1615 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
1616 {
1617 	int i;
1618 
1619 	for (i = 0; i < pcie->nr_channels; i++) {
1620 		struct kvaser_pciefd_can *can = pcie->can[i];
1621 
1622 		if (can) {
1623 			iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1624 			unregister_candev(can->can.dev);
1625 			del_timer(&can->bec_poll_timer);
1626 			kvaser_pciefd_pwm_stop(can);
1627 			free_candev(can->can.dev);
1628 		}
1629 	}
1630 }
1631 
1632 static void kvaser_pciefd_remove(struct pci_dev *pdev)
1633 {
1634 	struct kvaser_pciefd *pcie = pci_get_drvdata(pdev);
1635 
1636 	kvaser_pciefd_remove_all_ctrls(pcie);
1637 
1638 	/* Disable interrupts */
1639 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1640 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1641 
1642 	free_irq(pcie->pci->irq, pcie);
1643 
1644 	pci_iounmap(pdev, pcie->reg_base);
1645 	pci_release_regions(pdev);
1646 	pci_disable_device(pdev);
1647 }
1648 
1649 static struct pci_driver kvaser_pciefd = {
1650 	.name = KVASER_PCIEFD_DRV_NAME,
1651 	.id_table = kvaser_pciefd_id_table,
1652 	.probe = kvaser_pciefd_probe,
1653 	.remove = kvaser_pciefd_remove,
1654 };
1655 
1656 module_pci_driver(kvaser_pciefd)
1657