xref: /openbmc/linux/drivers/net/can/kvaser_pciefd.c (revision 7a2eb736)
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  *  - Altera Avalon EPCS flash controller driver
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/device.h>
12 #include <linux/pci.h>
13 #include <linux/can/dev.h>
14 #include <linux/timer.h>
15 #include <linux/netdevice.h>
16 #include <linux/crc32.h>
17 #include <linux/iopoll.h>
18 
19 MODULE_LICENSE("Dual BSD/GPL");
20 MODULE_AUTHOR("Kvaser AB <support@kvaser.com>");
21 MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
22 
23 #define KVASER_PCIEFD_DRV_NAME "kvaser_pciefd"
24 
25 #define KVASER_PCIEFD_WAIT_TIMEOUT msecs_to_jiffies(1000)
26 #define KVASER_PCIEFD_BEC_POLL_FREQ (jiffies + msecs_to_jiffies(200))
27 #define KVASER_PCIEFD_MAX_ERR_REP 256
28 #define KVASER_PCIEFD_CAN_TX_MAX_COUNT 17
29 #define KVASER_PCIEFD_MAX_CAN_CHANNELS 4
30 #define KVASER_PCIEFD_DMA_COUNT 2
31 
32 #define KVASER_PCIEFD_DMA_SIZE (4 * 1024)
33 #define KVASER_PCIEFD_64BIT_DMA_BIT BIT(0)
34 
35 #define KVASER_PCIEFD_VENDOR 0x1a07
36 #define KVASER_PCIEFD_4HS_ID 0x0d
37 #define KVASER_PCIEFD_2HS_ID 0x0e
38 #define KVASER_PCIEFD_HS_ID 0x0f
39 #define KVASER_PCIEFD_MINIPCIE_HS_ID 0x10
40 #define KVASER_PCIEFD_MINIPCIE_2HS_ID 0x11
41 
42 /* PCIe IRQ registers */
43 #define KVASER_PCIEFD_IRQ_REG 0x40
44 #define KVASER_PCIEFD_IEN_REG 0x50
45 /* DMA map */
46 #define KVASER_PCIEFD_DMA_MAP_BASE 0x1000
47 /* Kvaser KCAN CAN controller registers */
48 #define KVASER_PCIEFD_KCAN0_BASE 0x10000
49 #define KVASER_PCIEFD_KCAN_BASE_OFFSET 0x1000
50 #define KVASER_PCIEFD_KCAN_FIFO_REG 0x100
51 #define KVASER_PCIEFD_KCAN_FIFO_LAST_REG 0x180
52 #define KVASER_PCIEFD_KCAN_CTRL_REG 0x2c0
53 #define KVASER_PCIEFD_KCAN_CMD_REG 0x400
54 #define KVASER_PCIEFD_KCAN_IEN_REG 0x408
55 #define KVASER_PCIEFD_KCAN_IRQ_REG 0x410
56 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_REG 0x414
57 #define KVASER_PCIEFD_KCAN_STAT_REG 0x418
58 #define KVASER_PCIEFD_KCAN_MODE_REG 0x41c
59 #define KVASER_PCIEFD_KCAN_BTRN_REG 0x420
60 #define KVASER_PCIEFD_KCAN_BTRD_REG 0x428
61 #define KVASER_PCIEFD_KCAN_PWM_REG 0x430
62 /* Loopback control register */
63 #define KVASER_PCIEFD_LOOP_REG 0x1f000
64 /* System identification and information registers */
65 #define KVASER_PCIEFD_SYSID_BASE 0x1f020
66 #define KVASER_PCIEFD_SYSID_VERSION_REG (KVASER_PCIEFD_SYSID_BASE + 0x8)
67 #define KVASER_PCIEFD_SYSID_CANFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0xc)
68 #define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
69 /* Shared receive buffer registers */
70 #define KVASER_PCIEFD_SRB_BASE 0x1f200
71 #define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
72 #define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
73 #define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
74 #define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
75 #define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
76 /* EPCS flash controller registers */
77 #define KVASER_PCIEFD_SPI_BASE 0x1fc00
78 #define KVASER_PCIEFD_SPI_RX_REG KVASER_PCIEFD_SPI_BASE
79 #define KVASER_PCIEFD_SPI_TX_REG (KVASER_PCIEFD_SPI_BASE + 0x4)
80 #define KVASER_PCIEFD_SPI_STATUS_REG (KVASER_PCIEFD_SPI_BASE + 0x8)
81 #define KVASER_PCIEFD_SPI_CTRL_REG (KVASER_PCIEFD_SPI_BASE + 0xc)
82 #define KVASER_PCIEFD_SPI_SSEL_REG (KVASER_PCIEFD_SPI_BASE + 0x14)
83 
84 #define KVASER_PCIEFD_IRQ_ALL_MSK 0x1f
85 #define KVASER_PCIEFD_IRQ_SRB BIT(4)
86 
87 #define KVASER_PCIEFD_SYSID_NRCHAN_SHIFT 24
88 #define KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT 16
89 #define KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT 1
90 
91 /* Reset DMA buffer 0, 1 and FIFO offset */
92 #define KVASER_PCIEFD_SRB_CMD_RDB0 BIT(4)
93 #define KVASER_PCIEFD_SRB_CMD_RDB1 BIT(5)
94 #define KVASER_PCIEFD_SRB_CMD_FOR BIT(0)
95 
96 /* DMA packet done, buffer 0 and 1 */
97 #define KVASER_PCIEFD_SRB_IRQ_DPD0 BIT(8)
98 #define KVASER_PCIEFD_SRB_IRQ_DPD1 BIT(9)
99 /* DMA overflow, buffer 0 and 1 */
100 #define KVASER_PCIEFD_SRB_IRQ_DOF0 BIT(10)
101 #define KVASER_PCIEFD_SRB_IRQ_DOF1 BIT(11)
102 /* DMA underflow, buffer 0 and 1 */
103 #define KVASER_PCIEFD_SRB_IRQ_DUF0 BIT(12)
104 #define KVASER_PCIEFD_SRB_IRQ_DUF1 BIT(13)
105 
106 /* DMA idle */
107 #define KVASER_PCIEFD_SRB_STAT_DI BIT(15)
108 /* DMA support */
109 #define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
110 
111 /* DMA Enable */
112 #define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
113 
114 /* EPCS flash controller definitions */
115 #define KVASER_PCIEFD_CFG_IMG_SZ (64 * 1024)
116 #define KVASER_PCIEFD_CFG_IMG_OFFSET (31 * 65536L)
117 #define KVASER_PCIEFD_CFG_MAX_PARAMS 256
118 #define KVASER_PCIEFD_CFG_MAGIC 0xcafef00d
119 #define KVASER_PCIEFD_CFG_PARAM_MAX_SZ 24
120 #define KVASER_PCIEFD_CFG_SYS_VER 1
121 #define KVASER_PCIEFD_CFG_PARAM_NR_CHAN 130
122 #define KVASER_PCIEFD_SPI_TMT BIT(5)
123 #define KVASER_PCIEFD_SPI_TRDY BIT(6)
124 #define KVASER_PCIEFD_SPI_RRDY BIT(7)
125 #define KVASER_PCIEFD_FLASH_ID_EPCS16 0x14
126 /* Commands for controlling the onboard flash */
127 #define KVASER_PCIEFD_FLASH_RES_CMD 0xab
128 #define KVASER_PCIEFD_FLASH_READ_CMD 0x3
129 #define KVASER_PCIEFD_FLASH_STATUS_CMD 0x5
130 
131 /* Kvaser KCAN definitions */
132 #define KVASER_PCIEFD_KCAN_CTRL_EFLUSH (4 << 29)
133 #define KVASER_PCIEFD_KCAN_CTRL_EFRAME (5 << 29)
134 
135 #define KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT 16
136 /* Request status packet */
137 #define KVASER_PCIEFD_KCAN_CMD_SRQ BIT(0)
138 /* Abort, flush and reset */
139 #define KVASER_PCIEFD_KCAN_CMD_AT BIT(1)
140 
141 /* Tx FIFO unaligned read */
142 #define KVASER_PCIEFD_KCAN_IRQ_TAR BIT(0)
143 /* Tx FIFO unaligned end */
144 #define KVASER_PCIEFD_KCAN_IRQ_TAE BIT(1)
145 /* Bus parameter protection error */
146 #define KVASER_PCIEFD_KCAN_IRQ_BPP BIT(2)
147 /* FDF bit when controller is in classic mode */
148 #define KVASER_PCIEFD_KCAN_IRQ_FDIC BIT(3)
149 /* Rx FIFO overflow */
150 #define KVASER_PCIEFD_KCAN_IRQ_ROF BIT(5)
151 /* Abort done */
152 #define KVASER_PCIEFD_KCAN_IRQ_ABD BIT(13)
153 /* Tx buffer flush done */
154 #define KVASER_PCIEFD_KCAN_IRQ_TFD BIT(14)
155 /* Tx FIFO overflow */
156 #define KVASER_PCIEFD_KCAN_IRQ_TOF BIT(15)
157 /* Tx FIFO empty */
158 #define KVASER_PCIEFD_KCAN_IRQ_TE BIT(16)
159 /* Transmitter unaligned */
160 #define KVASER_PCIEFD_KCAN_IRQ_TAL BIT(17)
161 
162 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT 16
163 
164 #define KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT 24
165 /* Abort request */
166 #define KVASER_PCIEFD_KCAN_STAT_AR BIT(7)
167 /* Idle state. Controller in reset mode and no abort or flush pending */
168 #define KVASER_PCIEFD_KCAN_STAT_IDLE BIT(10)
169 /* Bus off */
170 #define KVASER_PCIEFD_KCAN_STAT_BOFF BIT(11)
171 /* Reset mode request */
172 #define KVASER_PCIEFD_KCAN_STAT_RMR BIT(14)
173 /* Controller in reset mode */
174 #define KVASER_PCIEFD_KCAN_STAT_IRM BIT(15)
175 /* Controller got one-shot capability */
176 #define KVASER_PCIEFD_KCAN_STAT_CAP BIT(16)
177 /* Controller got CAN FD capability */
178 #define KVASER_PCIEFD_KCAN_STAT_FD BIT(19)
179 #define KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK (KVASER_PCIEFD_KCAN_STAT_AR | \
180 	KVASER_PCIEFD_KCAN_STAT_BOFF | KVASER_PCIEFD_KCAN_STAT_RMR | \
181 	KVASER_PCIEFD_KCAN_STAT_IRM)
182 
183 /* Reset mode */
184 #define KVASER_PCIEFD_KCAN_MODE_RM BIT(8)
185 /* Listen only mode */
186 #define KVASER_PCIEFD_KCAN_MODE_LOM BIT(9)
187 /* Error packet enable */
188 #define KVASER_PCIEFD_KCAN_MODE_EPEN BIT(12)
189 /* CAN FD non-ISO */
190 #define KVASER_PCIEFD_KCAN_MODE_NIFDEN BIT(15)
191 /* Acknowledgment packet type */
192 #define KVASER_PCIEFD_KCAN_MODE_APT BIT(20)
193 /* Active error flag enable. Clear to force error passive */
194 #define KVASER_PCIEFD_KCAN_MODE_EEN BIT(23)
195 /* Classic CAN mode */
196 #define KVASER_PCIEFD_KCAN_MODE_CCM BIT(31)
197 
198 #define KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT 13
199 #define KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT 17
200 #define KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT 26
201 
202 #define KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT 16
203 
204 /* Kvaser KCAN packet types */
205 #define KVASER_PCIEFD_PACK_TYPE_DATA 0
206 #define KVASER_PCIEFD_PACK_TYPE_ACK 1
207 #define KVASER_PCIEFD_PACK_TYPE_TXRQ 2
208 #define KVASER_PCIEFD_PACK_TYPE_ERROR 3
209 #define KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK 4
210 #define KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK 5
211 #define KVASER_PCIEFD_PACK_TYPE_ACK_DATA 6
212 #define KVASER_PCIEFD_PACK_TYPE_STATUS 8
213 #define KVASER_PCIEFD_PACK_TYPE_BUS_LOAD 9
214 
215 /* Kvaser KCAN packet common definitions */
216 #define KVASER_PCIEFD_PACKET_SEQ_MSK 0xff
217 #define KVASER_PCIEFD_PACKET_CHID_SHIFT 25
218 #define KVASER_PCIEFD_PACKET_TYPE_SHIFT 28
219 
220 /* Kvaser KCAN TDATA and RDATA first word */
221 #define KVASER_PCIEFD_RPACKET_IDE BIT(30)
222 #define KVASER_PCIEFD_RPACKET_RTR BIT(29)
223 /* Kvaser KCAN TDATA and RDATA second word */
224 #define KVASER_PCIEFD_RPACKET_ESI BIT(13)
225 #define KVASER_PCIEFD_RPACKET_BRS BIT(14)
226 #define KVASER_PCIEFD_RPACKET_FDF BIT(15)
227 #define KVASER_PCIEFD_RPACKET_DLC_SHIFT 8
228 /* Kvaser KCAN TDATA second word */
229 #define KVASER_PCIEFD_TPACKET_SMS BIT(16)
230 #define KVASER_PCIEFD_TPACKET_AREQ BIT(31)
231 
232 /* Kvaser KCAN APACKET */
233 #define KVASER_PCIEFD_APACKET_FLU BIT(8)
234 #define KVASER_PCIEFD_APACKET_CT BIT(9)
235 #define KVASER_PCIEFD_APACKET_ABL BIT(10)
236 #define KVASER_PCIEFD_APACKET_NACK BIT(11)
237 
238 /* Kvaser KCAN SPACK first word */
239 #define KVASER_PCIEFD_SPACK_RXERR_SHIFT 8
240 #define KVASER_PCIEFD_SPACK_BOFF BIT(16)
241 #define KVASER_PCIEFD_SPACK_IDET BIT(20)
242 #define KVASER_PCIEFD_SPACK_IRM BIT(21)
243 #define KVASER_PCIEFD_SPACK_RMCD BIT(22)
244 /* Kvaser KCAN SPACK second word */
245 #define KVASER_PCIEFD_SPACK_AUTO BIT(21)
246 #define KVASER_PCIEFD_SPACK_EWLR BIT(23)
247 #define KVASER_PCIEFD_SPACK_EPLR BIT(24)
248 
249 struct kvaser_pciefd;
250 
251 struct kvaser_pciefd_can {
252 	struct can_priv can;
253 	struct kvaser_pciefd *kv_pcie;
254 	void __iomem *reg_base;
255 	struct can_berr_counter bec;
256 	u8 cmd_seq;
257 	int err_rep_cnt;
258 	int echo_idx;
259 	spinlock_t lock; /* Locks sensitive registers (e.g. MODE) */
260 	spinlock_t echo_lock; /* Locks the message echo buffer */
261 	struct timer_list bec_poll_timer;
262 	struct completion start_comp, flush_comp;
263 };
264 
265 struct kvaser_pciefd {
266 	struct pci_dev *pci;
267 	void __iomem *reg_base;
268 	struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
269 	void *dma_data[KVASER_PCIEFD_DMA_COUNT];
270 	u8 nr_channels;
271 	u32 freq;
272 	u32 freq_to_ticks_div;
273 };
274 
275 struct kvaser_pciefd_rx_packet {
276 	u32 header[2];
277 	u64 timestamp;
278 };
279 
280 struct kvaser_pciefd_tx_packet {
281 	u32 header[2];
282 	u8 data[64];
283 };
284 
285 static const struct can_bittiming_const kvaser_pciefd_bittiming_const = {
286 	.name = KVASER_PCIEFD_DRV_NAME,
287 	.tseg1_min = 1,
288 	.tseg1_max = 255,
289 	.tseg2_min = 1,
290 	.tseg2_max = 32,
291 	.sjw_max = 16,
292 	.brp_min = 1,
293 	.brp_max = 4096,
294 	.brp_inc = 1,
295 };
296 
297 struct kvaser_pciefd_cfg_param {
298 	__le32 magic;
299 	__le32 nr;
300 	__le32 len;
301 	u8 data[KVASER_PCIEFD_CFG_PARAM_MAX_SZ];
302 };
303 
304 struct kvaser_pciefd_cfg_img {
305 	__le32 version;
306 	__le32 magic;
307 	__le32 crc;
308 	struct kvaser_pciefd_cfg_param params[KVASER_PCIEFD_CFG_MAX_PARAMS];
309 };
310 
311 static struct pci_device_id kvaser_pciefd_id_table[] = {
312 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_4HS_ID), },
313 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_2HS_ID), },
314 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_HS_ID), },
315 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_HS_ID), },
316 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_2HS_ID), },
317 	{ 0,},
318 };
319 MODULE_DEVICE_TABLE(pci, kvaser_pciefd_id_table);
320 
321 /* Onboard flash memory functions */
322 static int kvaser_pciefd_spi_wait_loop(struct kvaser_pciefd *pcie, int msk)
323 {
324 	u32 res;
325 	int ret;
326 
327 	ret = readl_poll_timeout(pcie->reg_base + KVASER_PCIEFD_SPI_STATUS_REG,
328 				 res, res & msk, 0, 10);
329 
330 	return ret;
331 }
332 
333 static int kvaser_pciefd_spi_cmd(struct kvaser_pciefd *pcie, const u8 *tx,
334 				 u32 tx_len, u8 *rx, u32 rx_len)
335 {
336 	int c;
337 
338 	iowrite32(BIT(0), pcie->reg_base + KVASER_PCIEFD_SPI_SSEL_REG);
339 	iowrite32(BIT(10), pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
340 	ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
341 
342 	c = tx_len;
343 	while (c--) {
344 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
345 			return -EIO;
346 
347 		iowrite32(*tx++, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
348 
349 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
350 			return -EIO;
351 
352 		ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
353 	}
354 
355 	c = rx_len;
356 	while (c-- > 0) {
357 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
358 			return -EIO;
359 
360 		iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
361 
362 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
363 			return -EIO;
364 
365 		*rx++ = ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
366 	}
367 
368 	if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TMT))
369 		return -EIO;
370 
371 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
372 
373 	if (c != -1) {
374 		dev_err(&pcie->pci->dev, "Flash SPI transfer failed\n");
375 		return -EIO;
376 	}
377 
378 	return 0;
379 }
380 
381 static int kvaser_pciefd_cfg_read_and_verify(struct kvaser_pciefd *pcie,
382 					     struct kvaser_pciefd_cfg_img *img)
383 {
384 	int offset = KVASER_PCIEFD_CFG_IMG_OFFSET;
385 	int res, crc;
386 	u8 *crc_buff;
387 
388 	u8 cmd[] = {
389 		KVASER_PCIEFD_FLASH_READ_CMD,
390 		(u8)((offset >> 16) & 0xff),
391 		(u8)((offset >> 8) & 0xff),
392 		(u8)(offset & 0xff)
393 	};
394 
395 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), (u8 *)img,
396 				    KVASER_PCIEFD_CFG_IMG_SZ);
397 	if (res)
398 		return res;
399 
400 	crc_buff = (u8 *)img->params;
401 
402 	if (le32_to_cpu(img->version) != KVASER_PCIEFD_CFG_SYS_VER) {
403 		dev_err(&pcie->pci->dev,
404 			"Config flash corrupted, version number is wrong\n");
405 		return -ENODEV;
406 	}
407 
408 	if (le32_to_cpu(img->magic) != KVASER_PCIEFD_CFG_MAGIC) {
409 		dev_err(&pcie->pci->dev,
410 			"Config flash corrupted, magic number is wrong\n");
411 		return -ENODEV;
412 	}
413 
414 	crc = ~crc32_be(0xffffffff, crc_buff, sizeof(img->params));
415 	if (le32_to_cpu(img->crc) != crc) {
416 		dev_err(&pcie->pci->dev,
417 			"Stored CRC does not match flash image contents\n");
418 		return -EIO;
419 	}
420 
421 	return 0;
422 }
423 
424 static void kvaser_pciefd_cfg_read_params(struct kvaser_pciefd *pcie,
425 					  struct kvaser_pciefd_cfg_img *img)
426 {
427 	struct kvaser_pciefd_cfg_param *param;
428 
429 	param = &img->params[KVASER_PCIEFD_CFG_PARAM_NR_CHAN];
430 	memcpy(&pcie->nr_channels, param->data, le32_to_cpu(param->len));
431 }
432 
433 static int kvaser_pciefd_read_cfg(struct kvaser_pciefd *pcie)
434 {
435 	int res;
436 	struct kvaser_pciefd_cfg_img *img;
437 
438 	/* Read electronic signature */
439 	u8 cmd[] = {KVASER_PCIEFD_FLASH_RES_CMD, 0, 0, 0};
440 
441 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), cmd, 1);
442 	if (res)
443 		return -EIO;
444 
445 	img = kmalloc(KVASER_PCIEFD_CFG_IMG_SZ, GFP_KERNEL);
446 	if (!img)
447 		return -ENOMEM;
448 
449 	if (cmd[0] != KVASER_PCIEFD_FLASH_ID_EPCS16) {
450 		dev_err(&pcie->pci->dev,
451 			"Flash id is 0x%x instead of expected EPCS16 (0x%x)\n",
452 			cmd[0], KVASER_PCIEFD_FLASH_ID_EPCS16);
453 
454 		res = -ENODEV;
455 		goto image_free;
456 	}
457 
458 	cmd[0] = KVASER_PCIEFD_FLASH_STATUS_CMD;
459 	res = kvaser_pciefd_spi_cmd(pcie, cmd, 1, cmd, 1);
460 	if (res) {
461 		goto image_free;
462 	} else if (cmd[0] & 1) {
463 		res = -EIO;
464 		/* No write is ever done, the WIP should never be set */
465 		dev_err(&pcie->pci->dev, "Unexpected WIP bit set in flash\n");
466 		goto image_free;
467 	}
468 
469 	res = kvaser_pciefd_cfg_read_and_verify(pcie, img);
470 	if (res) {
471 		res = -EIO;
472 		goto image_free;
473 	}
474 
475 	kvaser_pciefd_cfg_read_params(pcie, img);
476 
477 image_free:
478 	kfree(img);
479 	return res;
480 }
481 
482 static void kvaser_pciefd_request_status(struct kvaser_pciefd_can *can)
483 {
484 	u32 cmd;
485 
486 	cmd = KVASER_PCIEFD_KCAN_CMD_SRQ;
487 	cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
488 	iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
489 }
490 
491 static void kvaser_pciefd_enable_err_gen(struct kvaser_pciefd_can *can)
492 {
493 	u32 mode;
494 	unsigned long irq;
495 
496 	spin_lock_irqsave(&can->lock, irq);
497 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
498 	if (!(mode & KVASER_PCIEFD_KCAN_MODE_EPEN)) {
499 		mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
500 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
501 	}
502 	spin_unlock_irqrestore(&can->lock, irq);
503 }
504 
505 static void kvaser_pciefd_disable_err_gen(struct kvaser_pciefd_can *can)
506 {
507 	u32 mode;
508 	unsigned long irq;
509 
510 	spin_lock_irqsave(&can->lock, irq);
511 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
512 	mode &= ~KVASER_PCIEFD_KCAN_MODE_EPEN;
513 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
514 	spin_unlock_irqrestore(&can->lock, irq);
515 }
516 
517 static int kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
518 {
519 	u32 msk;
520 
521 	msk = KVASER_PCIEFD_KCAN_IRQ_TE | KVASER_PCIEFD_KCAN_IRQ_ROF |
522 	      KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD |
523 	      KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL |
524 	      KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP |
525 	      KVASER_PCIEFD_KCAN_IRQ_TAR | KVASER_PCIEFD_KCAN_IRQ_TFD;
526 
527 	iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
528 
529 	return 0;
530 }
531 
532 static void kvaser_pciefd_setup_controller(struct kvaser_pciefd_can *can)
533 {
534 	u32 mode;
535 	unsigned long irq;
536 
537 	spin_lock_irqsave(&can->lock, irq);
538 
539 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
540 	if (can->can.ctrlmode & CAN_CTRLMODE_FD) {
541 		mode &= ~KVASER_PCIEFD_KCAN_MODE_CCM;
542 		if (can->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
543 			mode |= KVASER_PCIEFD_KCAN_MODE_NIFDEN;
544 		else
545 			mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
546 	} else {
547 		mode |= KVASER_PCIEFD_KCAN_MODE_CCM;
548 		mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
549 	}
550 
551 	if (can->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
552 		mode |= KVASER_PCIEFD_KCAN_MODE_LOM;
553 
554 	mode |= KVASER_PCIEFD_KCAN_MODE_EEN;
555 	mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
556 	/* Use ACK packet type */
557 	mode &= ~KVASER_PCIEFD_KCAN_MODE_APT;
558 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
559 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
560 
561 	spin_unlock_irqrestore(&can->lock, irq);
562 }
563 
564 static void kvaser_pciefd_start_controller_flush(struct kvaser_pciefd_can *can)
565 {
566 	u32 status;
567 	unsigned long irq;
568 
569 	spin_lock_irqsave(&can->lock, irq);
570 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
571 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
572 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
573 
574 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
575 	if (status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
576 		u32 cmd;
577 
578 		/* If controller is already idle, run abort, flush and reset */
579 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
580 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
581 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
582 	} else if (!(status & KVASER_PCIEFD_KCAN_STAT_RMR)) {
583 		u32 mode;
584 
585 		/* Put controller in reset mode */
586 		mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
587 		mode |= KVASER_PCIEFD_KCAN_MODE_RM;
588 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
589 	}
590 
591 	spin_unlock_irqrestore(&can->lock, irq);
592 }
593 
594 static int kvaser_pciefd_bus_on(struct kvaser_pciefd_can *can)
595 {
596 	u32 mode;
597 	unsigned long irq;
598 
599 	del_timer(&can->bec_poll_timer);
600 
601 	if (!completion_done(&can->flush_comp))
602 		kvaser_pciefd_start_controller_flush(can);
603 
604 	if (!wait_for_completion_timeout(&can->flush_comp,
605 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
606 		netdev_err(can->can.dev, "Timeout during bus on flush\n");
607 		return -ETIMEDOUT;
608 	}
609 
610 	spin_lock_irqsave(&can->lock, irq);
611 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
612 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
613 
614 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
615 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
616 
617 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
618 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
619 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
620 	spin_unlock_irqrestore(&can->lock, irq);
621 
622 	if (!wait_for_completion_timeout(&can->start_comp,
623 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
624 		netdev_err(can->can.dev, "Timeout during bus on reset\n");
625 		return -ETIMEDOUT;
626 	}
627 	/* Reset interrupt handling */
628 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
629 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
630 
631 	kvaser_pciefd_set_tx_irq(can);
632 	kvaser_pciefd_setup_controller(can);
633 
634 	can->can.state = CAN_STATE_ERROR_ACTIVE;
635 	netif_wake_queue(can->can.dev);
636 	can->bec.txerr = 0;
637 	can->bec.rxerr = 0;
638 	can->err_rep_cnt = 0;
639 
640 	return 0;
641 }
642 
643 static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
644 {
645 	u8 top;
646 	u32 pwm_ctrl;
647 	unsigned long irq;
648 
649 	spin_lock_irqsave(&can->lock, irq);
650 	pwm_ctrl = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
651 	top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;
652 
653 	/* Set duty cycle to zero */
654 	pwm_ctrl |= top;
655 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
656 	spin_unlock_irqrestore(&can->lock, irq);
657 }
658 
659 static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
660 {
661 	int top, trigger;
662 	u32 pwm_ctrl;
663 	unsigned long irq;
664 
665 	kvaser_pciefd_pwm_stop(can);
666 	spin_lock_irqsave(&can->lock, irq);
667 
668 	/* Set frequency to 500 KHz*/
669 	top = can->can.clock.freq / (2 * 500000) - 1;
670 
671 	pwm_ctrl = top & 0xff;
672 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
673 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
674 
675 	/* Set duty cycle to 95 */
676 	trigger = (100 * top - 95 * (top + 1) + 50) / 100;
677 	pwm_ctrl = trigger & 0xff;
678 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
679 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
680 	spin_unlock_irqrestore(&can->lock, irq);
681 }
682 
683 static int kvaser_pciefd_open(struct net_device *netdev)
684 {
685 	int err;
686 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
687 
688 	err = open_candev(netdev);
689 	if (err)
690 		return err;
691 
692 	err = kvaser_pciefd_bus_on(can);
693 	if (err)
694 		return err;
695 
696 	return 0;
697 }
698 
699 static int kvaser_pciefd_stop(struct net_device *netdev)
700 {
701 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
702 	int ret = 0;
703 
704 	/* Don't interrupt ongoing flush */
705 	if (!completion_done(&can->flush_comp))
706 		kvaser_pciefd_start_controller_flush(can);
707 
708 	if (!wait_for_completion_timeout(&can->flush_comp,
709 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
710 		netdev_err(can->can.dev, "Timeout during stop\n");
711 		ret = -ETIMEDOUT;
712 	} else {
713 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
714 		del_timer(&can->bec_poll_timer);
715 	}
716 	close_candev(netdev);
717 
718 	return ret;
719 }
720 
721 static int kvaser_pciefd_prepare_tx_packet(struct kvaser_pciefd_tx_packet *p,
722 					   struct kvaser_pciefd_can *can,
723 					   struct sk_buff *skb)
724 {
725 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
726 	int packet_size;
727 	int seq = can->echo_idx;
728 
729 	memset(p, 0, sizeof(*p));
730 
731 	if (can->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
732 		p->header[1] |= KVASER_PCIEFD_TPACKET_SMS;
733 
734 	if (cf->can_id & CAN_RTR_FLAG)
735 		p->header[0] |= KVASER_PCIEFD_RPACKET_RTR;
736 
737 	if (cf->can_id & CAN_EFF_FLAG)
738 		p->header[0] |= KVASER_PCIEFD_RPACKET_IDE;
739 
740 	p->header[0] |= cf->can_id & CAN_EFF_MASK;
741 	p->header[1] |= can_len2dlc(cf->len) << KVASER_PCIEFD_RPACKET_DLC_SHIFT;
742 	p->header[1] |= KVASER_PCIEFD_TPACKET_AREQ;
743 
744 	if (can_is_canfd_skb(skb)) {
745 		p->header[1] |= KVASER_PCIEFD_RPACKET_FDF;
746 		if (cf->flags & CANFD_BRS)
747 			p->header[1] |= KVASER_PCIEFD_RPACKET_BRS;
748 		if (cf->flags & CANFD_ESI)
749 			p->header[1] |= KVASER_PCIEFD_RPACKET_ESI;
750 	}
751 
752 	p->header[1] |= seq & KVASER_PCIEFD_PACKET_SEQ_MSK;
753 
754 	packet_size = cf->len;
755 	memcpy(p->data, cf->data, packet_size);
756 
757 	return DIV_ROUND_UP(packet_size, 4);
758 }
759 
760 static netdev_tx_t kvaser_pciefd_start_xmit(struct sk_buff *skb,
761 					    struct net_device *netdev)
762 {
763 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
764 	unsigned long irq_flags;
765 	struct kvaser_pciefd_tx_packet packet;
766 	int nwords;
767 	u8 count;
768 
769 	if (can_dropped_invalid_skb(netdev, skb))
770 		return NETDEV_TX_OK;
771 
772 	nwords = kvaser_pciefd_prepare_tx_packet(&packet, can, skb);
773 
774 	spin_lock_irqsave(&can->echo_lock, irq_flags);
775 
776 	/* Prepare and save echo skb in internal slot */
777 	can_put_echo_skb(skb, netdev, can->echo_idx);
778 
779 	/* Move echo index to the next slot */
780 	can->echo_idx = (can->echo_idx + 1) % can->can.echo_skb_max;
781 
782 	/* Write header to fifo */
783 	iowrite32(packet.header[0],
784 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
785 	iowrite32(packet.header[1],
786 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
787 
788 	if (nwords) {
789 		u32 data_last = ((u32 *)packet.data)[nwords - 1];
790 
791 		/* Write data to fifo, except last word */
792 		iowrite32_rep(can->reg_base +
793 			      KVASER_PCIEFD_KCAN_FIFO_REG, packet.data,
794 			      nwords - 1);
795 		/* Write last word to end of fifo */
796 		__raw_writel(data_last, can->reg_base +
797 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
798 	} else {
799 		/* Complete write to fifo */
800 		__raw_writel(0, can->reg_base +
801 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
802 	}
803 
804 	count = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
805 	/* No room for a new message, stop the queue until at least one
806 	 * successful transmit
807 	 */
808 	if (count >= KVASER_PCIEFD_CAN_TX_MAX_COUNT ||
809 	    can->can.echo_skb[can->echo_idx])
810 		netif_stop_queue(netdev);
811 
812 	spin_unlock_irqrestore(&can->echo_lock, irq_flags);
813 
814 	return NETDEV_TX_OK;
815 }
816 
817 static int kvaser_pciefd_set_bittiming(struct kvaser_pciefd_can *can, bool data)
818 {
819 	u32 mode, test, btrn;
820 	unsigned long irq_flags;
821 	int ret;
822 	struct can_bittiming *bt;
823 
824 	if (data)
825 		bt = &can->can.data_bittiming;
826 	else
827 		bt = &can->can.bittiming;
828 
829 	btrn = ((bt->phase_seg2 - 1) & 0x1f) <<
830 	       KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT |
831 	       (((bt->prop_seg + bt->phase_seg1) - 1) & 0x1ff) <<
832 	       KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT |
833 	       ((bt->sjw - 1) & 0xf) << KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT |
834 	       ((bt->brp - 1) & 0x1fff);
835 
836 	spin_lock_irqsave(&can->lock, irq_flags);
837 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
838 
839 	/* Put the circuit in reset mode */
840 	iowrite32(mode | KVASER_PCIEFD_KCAN_MODE_RM,
841 		  can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
842 
843 	/* Can only set bittiming if in reset mode */
844 	ret = readl_poll_timeout(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG,
845 				 test, test & KVASER_PCIEFD_KCAN_MODE_RM,
846 				 0, 10);
847 
848 	if (ret) {
849 		spin_unlock_irqrestore(&can->lock, irq_flags);
850 		return -EBUSY;
851 	}
852 
853 	if (data)
854 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRD_REG);
855 	else
856 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRN_REG);
857 
858 	/* Restore previous reset mode status */
859 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
860 
861 	spin_unlock_irqrestore(&can->lock, irq_flags);
862 	return 0;
863 }
864 
865 static int kvaser_pciefd_set_nominal_bittiming(struct net_device *ndev)
866 {
867 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), false);
868 }
869 
870 static int kvaser_pciefd_set_data_bittiming(struct net_device *ndev)
871 {
872 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), true);
873 }
874 
875 static int kvaser_pciefd_set_mode(struct net_device *ndev, enum can_mode mode)
876 {
877 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
878 	int ret = 0;
879 
880 	switch (mode) {
881 	case CAN_MODE_START:
882 		if (!can->can.restart_ms)
883 			ret = kvaser_pciefd_bus_on(can);
884 		break;
885 	default:
886 		return -EOPNOTSUPP;
887 	}
888 
889 	return ret;
890 }
891 
892 static int kvaser_pciefd_get_berr_counter(const struct net_device *ndev,
893 					  struct can_berr_counter *bec)
894 {
895 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
896 
897 	bec->rxerr = can->bec.rxerr;
898 	bec->txerr = can->bec.txerr;
899 	return 0;
900 }
901 
902 static void kvaser_pciefd_bec_poll_timer(struct timer_list *data)
903 {
904 	struct kvaser_pciefd_can *can = from_timer(can, data, bec_poll_timer);
905 
906 	kvaser_pciefd_enable_err_gen(can);
907 	kvaser_pciefd_request_status(can);
908 	can->err_rep_cnt = 0;
909 }
910 
911 static const struct net_device_ops kvaser_pciefd_netdev_ops = {
912 	.ndo_open = kvaser_pciefd_open,
913 	.ndo_stop = kvaser_pciefd_stop,
914 	.ndo_start_xmit = kvaser_pciefd_start_xmit,
915 	.ndo_change_mtu = can_change_mtu,
916 };
917 
918 static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
919 {
920 	int i;
921 
922 	for (i = 0; i < pcie->nr_channels; i++) {
923 		struct net_device *netdev;
924 		struct kvaser_pciefd_can *can;
925 		u32 status, tx_npackets;
926 
927 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
928 				      KVASER_PCIEFD_CAN_TX_MAX_COUNT);
929 		if (!netdev)
930 			return -ENOMEM;
931 
932 		can = netdev_priv(netdev);
933 		netdev->netdev_ops = &kvaser_pciefd_netdev_ops;
934 		can->reg_base = pcie->reg_base + KVASER_PCIEFD_KCAN0_BASE +
935 				i * KVASER_PCIEFD_KCAN_BASE_OFFSET;
936 
937 		can->kv_pcie = pcie;
938 		can->cmd_seq = 0;
939 		can->err_rep_cnt = 0;
940 		can->bec.txerr = 0;
941 		can->bec.rxerr = 0;
942 
943 		init_completion(&can->start_comp);
944 		init_completion(&can->flush_comp);
945 		timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer,
946 			    0);
947 
948 		tx_npackets = ioread32(can->reg_base +
949 				       KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
950 		if (((tx_npackets >> KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT) &
951 		      0xff) < KVASER_PCIEFD_CAN_TX_MAX_COUNT) {
952 			dev_err(&pcie->pci->dev,
953 				"Max Tx count is smaller than expected\n");
954 
955 			free_candev(netdev);
956 			return -ENODEV;
957 		}
958 
959 		can->can.clock.freq = pcie->freq;
960 		can->can.echo_skb_max = KVASER_PCIEFD_CAN_TX_MAX_COUNT;
961 		can->echo_idx = 0;
962 		spin_lock_init(&can->echo_lock);
963 		spin_lock_init(&can->lock);
964 		can->can.bittiming_const = &kvaser_pciefd_bittiming_const;
965 		can->can.data_bittiming_const = &kvaser_pciefd_bittiming_const;
966 
967 		can->can.do_set_bittiming = kvaser_pciefd_set_nominal_bittiming;
968 		can->can.do_set_data_bittiming =
969 			kvaser_pciefd_set_data_bittiming;
970 
971 		can->can.do_set_mode = kvaser_pciefd_set_mode;
972 		can->can.do_get_berr_counter = kvaser_pciefd_get_berr_counter;
973 
974 		can->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
975 					      CAN_CTRLMODE_FD |
976 					      CAN_CTRLMODE_FD_NON_ISO;
977 
978 		status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
979 		if (!(status & KVASER_PCIEFD_KCAN_STAT_FD)) {
980 			dev_err(&pcie->pci->dev,
981 				"CAN FD not supported as expected %d\n", i);
982 
983 			free_candev(netdev);
984 			return -ENODEV;
985 		}
986 
987 		if (status & KVASER_PCIEFD_KCAN_STAT_CAP)
988 			can->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
989 
990 		netdev->flags |= IFF_ECHO;
991 
992 		SET_NETDEV_DEV(netdev, &pcie->pci->dev);
993 
994 		iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
995 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD |
996 			  KVASER_PCIEFD_KCAN_IRQ_TFD,
997 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
998 
999 		pcie->can[i] = can;
1000 		kvaser_pciefd_pwm_start(can);
1001 	}
1002 
1003 	return 0;
1004 }
1005 
1006 static int kvaser_pciefd_reg_candev(struct kvaser_pciefd *pcie)
1007 {
1008 	int i;
1009 
1010 	for (i = 0; i < pcie->nr_channels; i++) {
1011 		int err = register_candev(pcie->can[i]->can.dev);
1012 
1013 		if (err) {
1014 			int j;
1015 
1016 			/* Unregister all successfully registered devices. */
1017 			for (j = 0; j < i; j++)
1018 				unregister_candev(pcie->can[j]->can.dev);
1019 			return err;
1020 		}
1021 	}
1022 
1023 	return 0;
1024 }
1025 
1026 static void kvaser_pciefd_write_dma_map(struct kvaser_pciefd *pcie,
1027 					dma_addr_t addr, int offset)
1028 {
1029 	u32 word1, word2;
1030 
1031 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
1032 	word1 = addr | KVASER_PCIEFD_64BIT_DMA_BIT;
1033 	word2 = addr >> 32;
1034 #else
1035 	word1 = addr;
1036 	word2 = 0;
1037 #endif
1038 	iowrite32(word1, pcie->reg_base + offset);
1039 	iowrite32(word2, pcie->reg_base + offset + 4);
1040 }
1041 
1042 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
1043 {
1044 	int i;
1045 	u32 srb_status;
1046 	dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
1047 
1048 	/* Disable the DMA */
1049 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1050 	for (i = 0; i < KVASER_PCIEFD_DMA_COUNT; i++) {
1051 		unsigned int offset = KVASER_PCIEFD_DMA_MAP_BASE + 8 * i;
1052 
1053 		pcie->dma_data[i] =
1054 			dmam_alloc_coherent(&pcie->pci->dev,
1055 					    KVASER_PCIEFD_DMA_SIZE,
1056 					    &dma_addr[i],
1057 					    GFP_KERNEL);
1058 
1059 		if (!pcie->dma_data[i] || !dma_addr[i]) {
1060 			dev_err(&pcie->pci->dev, "Rx dma_alloc(%u) failure\n",
1061 				KVASER_PCIEFD_DMA_SIZE);
1062 			return -ENOMEM;
1063 		}
1064 
1065 		kvaser_pciefd_write_dma_map(pcie, dma_addr[i], offset);
1066 	}
1067 
1068 	/* Reset Rx FIFO, and both DMA buffers */
1069 	iowrite32(KVASER_PCIEFD_SRB_CMD_FOR | KVASER_PCIEFD_SRB_CMD_RDB0 |
1070 		  KVASER_PCIEFD_SRB_CMD_RDB1,
1071 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1072 
1073 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1074 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
1075 		dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
1076 		return -EIO;
1077 	}
1078 
1079 	/* Enable the DMA */
1080 	iowrite32(KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE,
1081 		  pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1082 
1083 	return 0;
1084 }
1085 
1086 static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
1087 {
1088 	u32 sysid, srb_status, build;
1089 	u8 sysid_nr_chan;
1090 	int ret;
1091 
1092 	ret = kvaser_pciefd_read_cfg(pcie);
1093 	if (ret)
1094 		return ret;
1095 
1096 	sysid = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_VERSION_REG);
1097 	sysid_nr_chan = (sysid >> KVASER_PCIEFD_SYSID_NRCHAN_SHIFT) & 0xff;
1098 	if (pcie->nr_channels != sysid_nr_chan) {
1099 		dev_err(&pcie->pci->dev,
1100 			"Number of channels does not match: %u vs %u\n",
1101 			pcie->nr_channels,
1102 			sysid_nr_chan);
1103 		return -ENODEV;
1104 	}
1105 
1106 	if (pcie->nr_channels > KVASER_PCIEFD_MAX_CAN_CHANNELS)
1107 		pcie->nr_channels = KVASER_PCIEFD_MAX_CAN_CHANNELS;
1108 
1109 	build = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_BUILD_REG);
1110 	dev_dbg(&pcie->pci->dev, "Version %u.%u.%u\n",
1111 		(sysid >> KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT) & 0xff,
1112 		sysid & 0xff,
1113 		(build >> KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT) & 0x7fff);
1114 
1115 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1116 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DMA)) {
1117 		dev_err(&pcie->pci->dev,
1118 			"Hardware without DMA is not supported\n");
1119 		return -ENODEV;
1120 	}
1121 
1122 	pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
1123 	pcie->freq_to_ticks_div = pcie->freq / 1000000;
1124 	if (pcie->freq_to_ticks_div == 0)
1125 		pcie->freq_to_ticks_div = 1;
1126 
1127 	/* Turn off all loopback functionality */
1128 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_LOOP_REG);
1129 	return ret;
1130 }
1131 
1132 static int kvaser_pciefd_handle_data_packet(struct kvaser_pciefd *pcie,
1133 					    struct kvaser_pciefd_rx_packet *p,
1134 					    __le32 *data)
1135 {
1136 	struct sk_buff *skb;
1137 	struct canfd_frame *cf;
1138 	struct can_priv *priv;
1139 	struct net_device_stats *stats;
1140 	struct skb_shared_hwtstamps *shhwtstamps;
1141 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1142 
1143 	if (ch_id >= pcie->nr_channels)
1144 		return -EIO;
1145 
1146 	priv = &pcie->can[ch_id]->can;
1147 	stats = &priv->dev->stats;
1148 
1149 	if (p->header[1] & KVASER_PCIEFD_RPACKET_FDF) {
1150 		skb = alloc_canfd_skb(priv->dev, &cf);
1151 		if (!skb) {
1152 			stats->rx_dropped++;
1153 			return -ENOMEM;
1154 		}
1155 
1156 		if (p->header[1] & KVASER_PCIEFD_RPACKET_BRS)
1157 			cf->flags |= CANFD_BRS;
1158 
1159 		if (p->header[1] & KVASER_PCIEFD_RPACKET_ESI)
1160 			cf->flags |= CANFD_ESI;
1161 	} else {
1162 		skb = alloc_can_skb(priv->dev, (struct can_frame **)&cf);
1163 		if (!skb) {
1164 			stats->rx_dropped++;
1165 			return -ENOMEM;
1166 		}
1167 	}
1168 
1169 	cf->can_id = p->header[0] & CAN_EFF_MASK;
1170 	if (p->header[0] & KVASER_PCIEFD_RPACKET_IDE)
1171 		cf->can_id |= CAN_EFF_FLAG;
1172 
1173 	cf->len = can_dlc2len(p->header[1] >> KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1174 
1175 	if (p->header[0] & KVASER_PCIEFD_RPACKET_RTR)
1176 		cf->can_id |= CAN_RTR_FLAG;
1177 	else
1178 		memcpy(cf->data, data, cf->len);
1179 
1180 	shhwtstamps = skb_hwtstamps(skb);
1181 
1182 	shhwtstamps->hwtstamp =
1183 		ns_to_ktime(div_u64(p->timestamp * 1000,
1184 				    pcie->freq_to_ticks_div));
1185 
1186 	stats->rx_bytes += cf->len;
1187 	stats->rx_packets++;
1188 
1189 	return netif_rx(skb);
1190 }
1191 
1192 static void kvaser_pciefd_change_state(struct kvaser_pciefd_can *can,
1193 				       struct can_frame *cf,
1194 				       enum can_state new_state,
1195 				       enum can_state tx_state,
1196 				       enum can_state rx_state)
1197 {
1198 	can_change_state(can->can.dev, cf, tx_state, rx_state);
1199 
1200 	if (new_state == CAN_STATE_BUS_OFF) {
1201 		struct net_device *ndev = can->can.dev;
1202 		unsigned long irq_flags;
1203 
1204 		spin_lock_irqsave(&can->lock, irq_flags);
1205 		netif_stop_queue(can->can.dev);
1206 		spin_unlock_irqrestore(&can->lock, irq_flags);
1207 
1208 		/* Prevent CAN controller from auto recover from bus off */
1209 		if (!can->can.restart_ms) {
1210 			kvaser_pciefd_start_controller_flush(can);
1211 			can_bus_off(ndev);
1212 		}
1213 	}
1214 }
1215 
1216 static void kvaser_pciefd_packet_to_state(struct kvaser_pciefd_rx_packet *p,
1217 					  struct can_berr_counter *bec,
1218 					  enum can_state *new_state,
1219 					  enum can_state *tx_state,
1220 					  enum can_state *rx_state)
1221 {
1222 	if (p->header[0] & KVASER_PCIEFD_SPACK_BOFF ||
1223 	    p->header[0] & KVASER_PCIEFD_SPACK_IRM)
1224 		*new_state = CAN_STATE_BUS_OFF;
1225 	else if (bec->txerr >= 255 ||  bec->rxerr >= 255)
1226 		*new_state = CAN_STATE_BUS_OFF;
1227 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EPLR)
1228 		*new_state = CAN_STATE_ERROR_PASSIVE;
1229 	else if (bec->txerr >= 128 || bec->rxerr >= 128)
1230 		*new_state = CAN_STATE_ERROR_PASSIVE;
1231 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EWLR)
1232 		*new_state = CAN_STATE_ERROR_WARNING;
1233 	else if (bec->txerr >= 96 || bec->rxerr >= 96)
1234 		*new_state = CAN_STATE_ERROR_WARNING;
1235 	else
1236 		*new_state = CAN_STATE_ERROR_ACTIVE;
1237 
1238 	*tx_state = bec->txerr >= bec->rxerr ? *new_state : 0;
1239 	*rx_state = bec->txerr <= bec->rxerr ? *new_state : 0;
1240 }
1241 
1242 static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
1243 					struct kvaser_pciefd_rx_packet *p)
1244 {
1245 	struct can_berr_counter bec;
1246 	enum can_state old_state, new_state, tx_state, rx_state;
1247 	struct net_device *ndev = can->can.dev;
1248 	struct sk_buff *skb;
1249 	struct can_frame *cf = NULL;
1250 	struct skb_shared_hwtstamps *shhwtstamps;
1251 	struct net_device_stats *stats = &ndev->stats;
1252 
1253 	old_state = can->can.state;
1254 
1255 	bec.txerr = p->header[0] & 0xff;
1256 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1257 
1258 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1259 				      &rx_state);
1260 
1261 	skb = alloc_can_err_skb(ndev, &cf);
1262 
1263 	if (new_state != old_state) {
1264 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1265 					   rx_state);
1266 
1267 		if (old_state == CAN_STATE_BUS_OFF &&
1268 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1269 		    can->can.restart_ms) {
1270 			can->can.can_stats.restarts++;
1271 			if (skb)
1272 				cf->can_id |= CAN_ERR_RESTARTED;
1273 		}
1274 	}
1275 
1276 	can->err_rep_cnt++;
1277 	can->can.can_stats.bus_error++;
1278 	stats->rx_errors++;
1279 
1280 	can->bec.txerr = bec.txerr;
1281 	can->bec.rxerr = bec.rxerr;
1282 
1283 	if (!skb) {
1284 		stats->rx_dropped++;
1285 		return -ENOMEM;
1286 	}
1287 
1288 	shhwtstamps = skb_hwtstamps(skb);
1289 	shhwtstamps->hwtstamp =
1290 		ns_to_ktime(div_u64(p->timestamp * 1000,
1291 				    can->kv_pcie->freq_to_ticks_div));
1292 	cf->can_id |= CAN_ERR_BUSERROR;
1293 
1294 	cf->data[6] = bec.txerr;
1295 	cf->data[7] = bec.rxerr;
1296 
1297 	stats->rx_packets++;
1298 	stats->rx_bytes += cf->can_dlc;
1299 
1300 	netif_rx(skb);
1301 	return 0;
1302 }
1303 
1304 static int kvaser_pciefd_handle_error_packet(struct kvaser_pciefd *pcie,
1305 					     struct kvaser_pciefd_rx_packet *p)
1306 {
1307 	struct kvaser_pciefd_can *can;
1308 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1309 
1310 	if (ch_id >= pcie->nr_channels)
1311 		return -EIO;
1312 
1313 	can = pcie->can[ch_id];
1314 
1315 	kvaser_pciefd_rx_error_frame(can, p);
1316 	if (can->err_rep_cnt >= KVASER_PCIEFD_MAX_ERR_REP)
1317 		/* Do not report more errors, until bec_poll_timer expires */
1318 		kvaser_pciefd_disable_err_gen(can);
1319 	/* Start polling the error counters */
1320 	mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1321 	return 0;
1322 }
1323 
1324 static int kvaser_pciefd_handle_status_resp(struct kvaser_pciefd_can *can,
1325 					    struct kvaser_pciefd_rx_packet *p)
1326 {
1327 	struct can_berr_counter bec;
1328 	enum can_state old_state, new_state, tx_state, rx_state;
1329 
1330 	old_state = can->can.state;
1331 
1332 	bec.txerr = p->header[0] & 0xff;
1333 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1334 
1335 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1336 				      &rx_state);
1337 
1338 	if (new_state != old_state) {
1339 		struct net_device *ndev = can->can.dev;
1340 		struct sk_buff *skb;
1341 		struct can_frame *cf;
1342 		struct skb_shared_hwtstamps *shhwtstamps;
1343 
1344 		skb = alloc_can_err_skb(ndev, &cf);
1345 		if (!skb) {
1346 			struct net_device_stats *stats = &ndev->stats;
1347 
1348 			stats->rx_dropped++;
1349 			return -ENOMEM;
1350 		}
1351 
1352 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1353 					   rx_state);
1354 
1355 		if (old_state == CAN_STATE_BUS_OFF &&
1356 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1357 		    can->can.restart_ms) {
1358 			can->can.can_stats.restarts++;
1359 			cf->can_id |= CAN_ERR_RESTARTED;
1360 		}
1361 
1362 		shhwtstamps = skb_hwtstamps(skb);
1363 		shhwtstamps->hwtstamp =
1364 			ns_to_ktime(div_u64(p->timestamp * 1000,
1365 					    can->kv_pcie->freq_to_ticks_div));
1366 
1367 		cf->data[6] = bec.txerr;
1368 		cf->data[7] = bec.rxerr;
1369 
1370 		netif_rx(skb);
1371 	}
1372 	can->bec.txerr = bec.txerr;
1373 	can->bec.rxerr = bec.rxerr;
1374 	/* Check if we need to poll the error counters */
1375 	if (bec.txerr || bec.rxerr)
1376 		mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1377 
1378 	return 0;
1379 }
1380 
1381 static int kvaser_pciefd_handle_status_packet(struct kvaser_pciefd *pcie,
1382 					      struct kvaser_pciefd_rx_packet *p)
1383 {
1384 	struct kvaser_pciefd_can *can;
1385 	u8 cmdseq;
1386 	u32 status;
1387 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1388 
1389 	if (ch_id >= pcie->nr_channels)
1390 		return -EIO;
1391 
1392 	can = pcie->can[ch_id];
1393 
1394 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1395 	cmdseq = (status >> KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT) & 0xff;
1396 
1397 	/* Reset done, start abort and flush */
1398 	if (p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1399 	    p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1400 	    p->header[1] & KVASER_PCIEFD_SPACK_AUTO &&
1401 	    cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1402 	    status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1403 		u32 cmd;
1404 
1405 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1406 			  can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1407 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
1408 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
1409 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
1410 
1411 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_TFD,
1412 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1413 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET &&
1414 		   p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1415 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1416 		   status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1417 		/* Reset detected, send end of flush if no packet are in FIFO */
1418 		u8 count = ioread32(can->reg_base +
1419 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1420 
1421 		if (!count)
1422 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1423 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1424 	} else if (!(p->header[1] & KVASER_PCIEFD_SPACK_AUTO) &&
1425 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK)) {
1426 		/* Response to status request received */
1427 		kvaser_pciefd_handle_status_resp(can, p);
1428 		if (can->can.state != CAN_STATE_BUS_OFF &&
1429 		    can->can.state != CAN_STATE_ERROR_ACTIVE) {
1430 			mod_timer(&can->bec_poll_timer,
1431 				  KVASER_PCIEFD_BEC_POLL_FREQ);
1432 		}
1433 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1434 		   !(status & KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK)) {
1435 		/* Reset to bus on detected */
1436 		if (!completion_done(&can->start_comp))
1437 			complete(&can->start_comp);
1438 	}
1439 
1440 	return 0;
1441 }
1442 
1443 static int kvaser_pciefd_handle_eack_packet(struct kvaser_pciefd *pcie,
1444 					    struct kvaser_pciefd_rx_packet *p)
1445 {
1446 	struct kvaser_pciefd_can *can;
1447 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1448 
1449 	if (ch_id >= pcie->nr_channels)
1450 		return -EIO;
1451 
1452 	can = pcie->can[ch_id];
1453 
1454 	/* If this is the last flushed packet, send end of flush */
1455 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1456 		u8 count = ioread32(can->reg_base +
1457 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1458 
1459 		if (count == 0)
1460 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1461 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1462 	} else {
1463 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1464 		int dlc = can_get_echo_skb(can->can.dev, echo_idx);
1465 		struct net_device_stats *stats = &can->can.dev->stats;
1466 
1467 		stats->tx_bytes += dlc;
1468 		stats->tx_packets++;
1469 
1470 		if (netif_queue_stopped(can->can.dev))
1471 			netif_wake_queue(can->can.dev);
1472 	}
1473 
1474 	return 0;
1475 }
1476 
1477 static void kvaser_pciefd_handle_nack_packet(struct kvaser_pciefd_can *can,
1478 					     struct kvaser_pciefd_rx_packet *p)
1479 {
1480 	struct sk_buff *skb;
1481 	struct net_device_stats *stats = &can->can.dev->stats;
1482 	struct can_frame *cf;
1483 
1484 	skb = alloc_can_err_skb(can->can.dev, &cf);
1485 
1486 	stats->tx_errors++;
1487 	if (p->header[0] & KVASER_PCIEFD_APACKET_ABL) {
1488 		if (skb)
1489 			cf->can_id |= CAN_ERR_LOSTARB;
1490 		can->can.can_stats.arbitration_lost++;
1491 	} else if (skb) {
1492 		cf->can_id |= CAN_ERR_ACK;
1493 	}
1494 
1495 	if (skb) {
1496 		cf->can_id |= CAN_ERR_BUSERROR;
1497 		stats->rx_bytes += cf->can_dlc;
1498 		stats->rx_packets++;
1499 		netif_rx(skb);
1500 	} else {
1501 		stats->rx_dropped++;
1502 		netdev_warn(can->can.dev, "No memory left for err_skb\n");
1503 	}
1504 }
1505 
1506 static int kvaser_pciefd_handle_ack_packet(struct kvaser_pciefd *pcie,
1507 					   struct kvaser_pciefd_rx_packet *p)
1508 {
1509 	struct kvaser_pciefd_can *can;
1510 	bool one_shot_fail = false;
1511 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1512 
1513 	if (ch_id >= pcie->nr_channels)
1514 		return -EIO;
1515 
1516 	can = pcie->can[ch_id];
1517 	/* Ignore control packet ACK */
1518 	if (p->header[0] & KVASER_PCIEFD_APACKET_CT)
1519 		return 0;
1520 
1521 	if (p->header[0] & KVASER_PCIEFD_APACKET_NACK) {
1522 		kvaser_pciefd_handle_nack_packet(can, p);
1523 		one_shot_fail = true;
1524 	}
1525 
1526 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1527 		netdev_dbg(can->can.dev, "Packet was flushed\n");
1528 	} else {
1529 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1530 		int dlc = can_get_echo_skb(can->can.dev, echo_idx);
1531 		u8 count = ioread32(can->reg_base +
1532 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1533 
1534 		if (count < KVASER_PCIEFD_CAN_TX_MAX_COUNT &&
1535 		    netif_queue_stopped(can->can.dev))
1536 			netif_wake_queue(can->can.dev);
1537 
1538 		if (!one_shot_fail) {
1539 			struct net_device_stats *stats = &can->can.dev->stats;
1540 
1541 			stats->tx_bytes += dlc;
1542 			stats->tx_packets++;
1543 		}
1544 	}
1545 
1546 	return 0;
1547 }
1548 
1549 static int kvaser_pciefd_handle_eflush_packet(struct kvaser_pciefd *pcie,
1550 					      struct kvaser_pciefd_rx_packet *p)
1551 {
1552 	struct kvaser_pciefd_can *can;
1553 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1554 
1555 	if (ch_id >= pcie->nr_channels)
1556 		return -EIO;
1557 
1558 	can = pcie->can[ch_id];
1559 
1560 	if (!completion_done(&can->flush_comp))
1561 		complete(&can->flush_comp);
1562 
1563 	return 0;
1564 }
1565 
1566 static int kvaser_pciefd_read_packet(struct kvaser_pciefd *pcie, int *start_pos,
1567 				     int dma_buf)
1568 {
1569 	__le32 *buffer = pcie->dma_data[dma_buf];
1570 	__le64 timestamp;
1571 	struct kvaser_pciefd_rx_packet packet;
1572 	struct kvaser_pciefd_rx_packet *p = &packet;
1573 	u8 type;
1574 	int pos = *start_pos;
1575 	int size;
1576 	int ret = 0;
1577 
1578 	size = le32_to_cpu(buffer[pos++]);
1579 	if (!size) {
1580 		*start_pos = 0;
1581 		return 0;
1582 	}
1583 
1584 	p->header[0] = le32_to_cpu(buffer[pos++]);
1585 	p->header[1] = le32_to_cpu(buffer[pos++]);
1586 
1587 	/* Read 64-bit timestamp */
1588 	memcpy(&timestamp, &buffer[pos], sizeof(__le64));
1589 	pos += 2;
1590 	p->timestamp = le64_to_cpu(timestamp);
1591 
1592 	type = (p->header[1] >> KVASER_PCIEFD_PACKET_TYPE_SHIFT) & 0xf;
1593 	switch (type) {
1594 	case KVASER_PCIEFD_PACK_TYPE_DATA:
1595 		ret = kvaser_pciefd_handle_data_packet(pcie, p, &buffer[pos]);
1596 		if (!(p->header[0] & KVASER_PCIEFD_RPACKET_RTR)) {
1597 			u8 data_len;
1598 
1599 			data_len = can_dlc2len(p->header[1] >>
1600 					       KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1601 			pos += DIV_ROUND_UP(data_len, 4);
1602 		}
1603 		break;
1604 
1605 	case KVASER_PCIEFD_PACK_TYPE_ACK:
1606 		ret = kvaser_pciefd_handle_ack_packet(pcie, p);
1607 		break;
1608 
1609 	case KVASER_PCIEFD_PACK_TYPE_STATUS:
1610 		ret = kvaser_pciefd_handle_status_packet(pcie, p);
1611 		break;
1612 
1613 	case KVASER_PCIEFD_PACK_TYPE_ERROR:
1614 		ret = kvaser_pciefd_handle_error_packet(pcie, p);
1615 		break;
1616 
1617 	case KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK:
1618 		ret = kvaser_pciefd_handle_eack_packet(pcie, p);
1619 		break;
1620 
1621 	case KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK:
1622 		ret = kvaser_pciefd_handle_eflush_packet(pcie, p);
1623 		break;
1624 
1625 	case KVASER_PCIEFD_PACK_TYPE_ACK_DATA:
1626 	case KVASER_PCIEFD_PACK_TYPE_BUS_LOAD:
1627 	case KVASER_PCIEFD_PACK_TYPE_TXRQ:
1628 		dev_info(&pcie->pci->dev,
1629 			 "Received unexpected packet type 0x%08X\n", type);
1630 		break;
1631 
1632 	default:
1633 		dev_err(&pcie->pci->dev, "Unknown packet type 0x%08X\n", type);
1634 		ret = -EIO;
1635 		break;
1636 	}
1637 
1638 	if (ret)
1639 		return ret;
1640 
1641 	/* Position does not point to the end of the package,
1642 	 * corrupted packet size?
1643 	 */
1644 	if ((*start_pos + size) != pos)
1645 		return -EIO;
1646 
1647 	/* Point to the next packet header, if any */
1648 	*start_pos = pos;
1649 
1650 	return ret;
1651 }
1652 
1653 static int kvaser_pciefd_read_buffer(struct kvaser_pciefd *pcie, int dma_buf)
1654 {
1655 	int pos = 0;
1656 	int res = 0;
1657 
1658 	do {
1659 		res = kvaser_pciefd_read_packet(pcie, &pos, dma_buf);
1660 	} while (!res && pos > 0 && pos < KVASER_PCIEFD_DMA_SIZE);
1661 
1662 	return res;
1663 }
1664 
1665 static int kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
1666 {
1667 	u32 irq;
1668 
1669 	irq = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1670 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
1671 		kvaser_pciefd_read_buffer(pcie, 0);
1672 		/* Reset DMA buffer 0 */
1673 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1674 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1675 	}
1676 
1677 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
1678 		kvaser_pciefd_read_buffer(pcie, 1);
1679 		/* Reset DMA buffer 1 */
1680 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1681 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1682 	}
1683 
1684 	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
1685 	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
1686 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
1687 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
1688 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
1689 
1690 	iowrite32(irq, pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1691 	return 0;
1692 }
1693 
1694 static int kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
1695 {
1696 	u32 irq = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1697 
1698 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF)
1699 		netdev_err(can->can.dev, "Tx FIFO overflow\n");
1700 
1701 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TFD) {
1702 		u8 count = ioread32(can->reg_base +
1703 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1704 
1705 		if (count == 0)
1706 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1707 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1708 	}
1709 
1710 	if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP)
1711 		netdev_err(can->can.dev,
1712 			   "Fail to change bittiming, when not in reset mode\n");
1713 
1714 	if (irq & KVASER_PCIEFD_KCAN_IRQ_FDIC)
1715 		netdev_err(can->can.dev, "CAN FD frame in CAN mode\n");
1716 
1717 	if (irq & KVASER_PCIEFD_KCAN_IRQ_ROF)
1718 		netdev_err(can->can.dev, "Rx FIFO overflow\n");
1719 
1720 	iowrite32(irq, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1721 	return 0;
1722 }
1723 
1724 static irqreturn_t kvaser_pciefd_irq_handler(int irq, void *dev)
1725 {
1726 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
1727 	u32 board_irq;
1728 	int i;
1729 
1730 	board_irq = ioread32(pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1731 
1732 	if (!(board_irq & KVASER_PCIEFD_IRQ_ALL_MSK))
1733 		return IRQ_NONE;
1734 
1735 	if (board_irq & KVASER_PCIEFD_IRQ_SRB)
1736 		kvaser_pciefd_receive_irq(pcie);
1737 
1738 	for (i = 0; i < pcie->nr_channels; i++) {
1739 		if (!pcie->can[i]) {
1740 			dev_err(&pcie->pci->dev,
1741 				"IRQ mask points to unallocated controller\n");
1742 			break;
1743 		}
1744 
1745 		/* Check that mask matches channel (i) IRQ mask */
1746 		if (board_irq & (1 << i))
1747 			kvaser_pciefd_transmit_irq(pcie->can[i]);
1748 	}
1749 
1750 	iowrite32(board_irq, pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1751 	return IRQ_HANDLED;
1752 }
1753 
1754 static void kvaser_pciefd_teardown_can_ctrls(struct kvaser_pciefd *pcie)
1755 {
1756 	int i;
1757 	struct kvaser_pciefd_can *can;
1758 
1759 	for (i = 0; i < pcie->nr_channels; i++) {
1760 		can = pcie->can[i];
1761 		if (can) {
1762 			iowrite32(0,
1763 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1764 			kvaser_pciefd_pwm_stop(can);
1765 			free_candev(can->can.dev);
1766 		}
1767 	}
1768 }
1769 
1770 static int kvaser_pciefd_probe(struct pci_dev *pdev,
1771 			       const struct pci_device_id *id)
1772 {
1773 	int err;
1774 	struct kvaser_pciefd *pcie;
1775 
1776 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
1777 	if (!pcie)
1778 		return -ENOMEM;
1779 
1780 	pci_set_drvdata(pdev, pcie);
1781 	pcie->pci = pdev;
1782 
1783 	err = pci_enable_device(pdev);
1784 	if (err)
1785 		return err;
1786 
1787 	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
1788 	if (err)
1789 		goto err_disable_pci;
1790 
1791 	pcie->reg_base = pci_iomap(pdev, 0, 0);
1792 	if (!pcie->reg_base) {
1793 		err = -ENOMEM;
1794 		goto err_release_regions;
1795 	}
1796 
1797 	err = kvaser_pciefd_setup_board(pcie);
1798 	if (err)
1799 		goto err_pci_iounmap;
1800 
1801 	err = kvaser_pciefd_setup_dma(pcie);
1802 	if (err)
1803 		goto err_pci_iounmap;
1804 
1805 	pci_set_master(pdev);
1806 
1807 	err = kvaser_pciefd_setup_can_ctrls(pcie);
1808 	if (err)
1809 		goto err_teardown_can_ctrls;
1810 
1811 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
1812 		  pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1813 
1814 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1 |
1815 		  KVASER_PCIEFD_SRB_IRQ_DOF0 | KVASER_PCIEFD_SRB_IRQ_DOF1 |
1816 		  KVASER_PCIEFD_SRB_IRQ_DUF0 | KVASER_PCIEFD_SRB_IRQ_DUF1,
1817 		  pcie->reg_base + KVASER_PCIEFD_SRB_IEN_REG);
1818 
1819 	/* Reset IRQ handling, expected to be off before */
1820 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1821 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1822 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1823 		  pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1824 
1825 	/* Ready the DMA buffers */
1826 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1827 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1828 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1829 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1830 
1831 	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
1832 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
1833 	if (err)
1834 		goto err_teardown_can_ctrls;
1835 
1836 	err = kvaser_pciefd_reg_candev(pcie);
1837 	if (err)
1838 		goto err_free_irq;
1839 
1840 	return 0;
1841 
1842 err_free_irq:
1843 	free_irq(pcie->pci->irq, pcie);
1844 
1845 err_teardown_can_ctrls:
1846 	kvaser_pciefd_teardown_can_ctrls(pcie);
1847 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1848 	pci_clear_master(pdev);
1849 
1850 err_pci_iounmap:
1851 	pci_iounmap(pdev, pcie->reg_base);
1852 
1853 err_release_regions:
1854 	pci_release_regions(pdev);
1855 
1856 err_disable_pci:
1857 	pci_disable_device(pdev);
1858 
1859 	return err;
1860 }
1861 
1862 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
1863 {
1864 	struct kvaser_pciefd_can *can;
1865 	int i;
1866 
1867 	for (i = 0; i < pcie->nr_channels; i++) {
1868 		can = pcie->can[i];
1869 		if (can) {
1870 			iowrite32(0,
1871 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1872 			unregister_candev(can->can.dev);
1873 			del_timer(&can->bec_poll_timer);
1874 			kvaser_pciefd_pwm_stop(can);
1875 			free_candev(can->can.dev);
1876 		}
1877 	}
1878 }
1879 
1880 static void kvaser_pciefd_remove(struct pci_dev *pdev)
1881 {
1882 	struct kvaser_pciefd *pcie = pci_get_drvdata(pdev);
1883 
1884 	kvaser_pciefd_remove_all_ctrls(pcie);
1885 
1886 	/* Turn off IRQ generation */
1887 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1888 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1889 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1890 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1891 
1892 	free_irq(pcie->pci->irq, pcie);
1893 
1894 	pci_clear_master(pdev);
1895 	pci_iounmap(pdev, pcie->reg_base);
1896 	pci_release_regions(pdev);
1897 	pci_disable_device(pdev);
1898 }
1899 
1900 static struct pci_driver kvaser_pciefd = {
1901 	.name = KVASER_PCIEFD_DRV_NAME,
1902 	.id_table = kvaser_pciefd_id_table,
1903 	.probe = kvaser_pciefd_probe,
1904 	.remove = kvaser_pciefd_remove,
1905 };
1906 
1907 module_pci_driver(kvaser_pciefd)
1908