xref: /linux/drivers/net/can/kvaser_pciefd.c (revision 34f7c6e7d4396090692a09789db231e12cb4762b)
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_BUS_LOAD_REG 0x424
61 #define KVASER_PCIEFD_KCAN_BTRD_REG 0x428
62 #define KVASER_PCIEFD_KCAN_PWM_REG 0x430
63 /* Loopback control register */
64 #define KVASER_PCIEFD_LOOP_REG 0x1f000
65 /* System identification and information registers */
66 #define KVASER_PCIEFD_SYSID_BASE 0x1f020
67 #define KVASER_PCIEFD_SYSID_VERSION_REG (KVASER_PCIEFD_SYSID_BASE + 0x8)
68 #define KVASER_PCIEFD_SYSID_CANFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0xc)
69 #define KVASER_PCIEFD_SYSID_BUSFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0x10)
70 #define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
71 /* Shared receive buffer registers */
72 #define KVASER_PCIEFD_SRB_BASE 0x1f200
73 #define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
74 #define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
75 #define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
76 #define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
77 #define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
78 /* EPCS flash controller registers */
79 #define KVASER_PCIEFD_SPI_BASE 0x1fc00
80 #define KVASER_PCIEFD_SPI_RX_REG KVASER_PCIEFD_SPI_BASE
81 #define KVASER_PCIEFD_SPI_TX_REG (KVASER_PCIEFD_SPI_BASE + 0x4)
82 #define KVASER_PCIEFD_SPI_STATUS_REG (KVASER_PCIEFD_SPI_BASE + 0x8)
83 #define KVASER_PCIEFD_SPI_CTRL_REG (KVASER_PCIEFD_SPI_BASE + 0xc)
84 #define KVASER_PCIEFD_SPI_SSEL_REG (KVASER_PCIEFD_SPI_BASE + 0x14)
85 
86 #define KVASER_PCIEFD_IRQ_ALL_MSK 0x1f
87 #define KVASER_PCIEFD_IRQ_SRB BIT(4)
88 
89 #define KVASER_PCIEFD_SYSID_NRCHAN_SHIFT 24
90 #define KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT 16
91 #define KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT 1
92 
93 /* Reset DMA buffer 0, 1 and FIFO offset */
94 #define KVASER_PCIEFD_SRB_CMD_RDB0 BIT(4)
95 #define KVASER_PCIEFD_SRB_CMD_RDB1 BIT(5)
96 #define KVASER_PCIEFD_SRB_CMD_FOR BIT(0)
97 
98 /* DMA packet done, buffer 0 and 1 */
99 #define KVASER_PCIEFD_SRB_IRQ_DPD0 BIT(8)
100 #define KVASER_PCIEFD_SRB_IRQ_DPD1 BIT(9)
101 /* DMA overflow, buffer 0 and 1 */
102 #define KVASER_PCIEFD_SRB_IRQ_DOF0 BIT(10)
103 #define KVASER_PCIEFD_SRB_IRQ_DOF1 BIT(11)
104 /* DMA underflow, buffer 0 and 1 */
105 #define KVASER_PCIEFD_SRB_IRQ_DUF0 BIT(12)
106 #define KVASER_PCIEFD_SRB_IRQ_DUF1 BIT(13)
107 
108 /* DMA idle */
109 #define KVASER_PCIEFD_SRB_STAT_DI BIT(15)
110 /* DMA support */
111 #define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
112 
113 /* DMA Enable */
114 #define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
115 
116 /* EPCS flash controller definitions */
117 #define KVASER_PCIEFD_CFG_IMG_SZ (64 * 1024)
118 #define KVASER_PCIEFD_CFG_IMG_OFFSET (31 * 65536L)
119 #define KVASER_PCIEFD_CFG_MAX_PARAMS 256
120 #define KVASER_PCIEFD_CFG_MAGIC 0xcafef00d
121 #define KVASER_PCIEFD_CFG_PARAM_MAX_SZ 24
122 #define KVASER_PCIEFD_CFG_SYS_VER 1
123 #define KVASER_PCIEFD_CFG_PARAM_NR_CHAN 130
124 #define KVASER_PCIEFD_SPI_TMT BIT(5)
125 #define KVASER_PCIEFD_SPI_TRDY BIT(6)
126 #define KVASER_PCIEFD_SPI_RRDY BIT(7)
127 #define KVASER_PCIEFD_FLASH_ID_EPCS16 0x14
128 /* Commands for controlling the onboard flash */
129 #define KVASER_PCIEFD_FLASH_RES_CMD 0xab
130 #define KVASER_PCIEFD_FLASH_READ_CMD 0x3
131 #define KVASER_PCIEFD_FLASH_STATUS_CMD 0x5
132 
133 /* Kvaser KCAN definitions */
134 #define KVASER_PCIEFD_KCAN_CTRL_EFLUSH (4 << 29)
135 #define KVASER_PCIEFD_KCAN_CTRL_EFRAME (5 << 29)
136 
137 #define KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT 16
138 /* Request status packet */
139 #define KVASER_PCIEFD_KCAN_CMD_SRQ BIT(0)
140 /* Abort, flush and reset */
141 #define KVASER_PCIEFD_KCAN_CMD_AT BIT(1)
142 
143 /* Tx FIFO unaligned read */
144 #define KVASER_PCIEFD_KCAN_IRQ_TAR BIT(0)
145 /* Tx FIFO unaligned end */
146 #define KVASER_PCIEFD_KCAN_IRQ_TAE BIT(1)
147 /* Bus parameter protection error */
148 #define KVASER_PCIEFD_KCAN_IRQ_BPP BIT(2)
149 /* FDF bit when controller is in classic mode */
150 #define KVASER_PCIEFD_KCAN_IRQ_FDIC BIT(3)
151 /* Rx FIFO overflow */
152 #define KVASER_PCIEFD_KCAN_IRQ_ROF BIT(5)
153 /* Abort done */
154 #define KVASER_PCIEFD_KCAN_IRQ_ABD BIT(13)
155 /* Tx buffer flush done */
156 #define KVASER_PCIEFD_KCAN_IRQ_TFD BIT(14)
157 /* Tx FIFO overflow */
158 #define KVASER_PCIEFD_KCAN_IRQ_TOF BIT(15)
159 /* Tx FIFO empty */
160 #define KVASER_PCIEFD_KCAN_IRQ_TE BIT(16)
161 /* Transmitter unaligned */
162 #define KVASER_PCIEFD_KCAN_IRQ_TAL BIT(17)
163 
164 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT 16
165 
166 #define KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT 24
167 /* Abort request */
168 #define KVASER_PCIEFD_KCAN_STAT_AR BIT(7)
169 /* Idle state. Controller in reset mode and no abort or flush pending */
170 #define KVASER_PCIEFD_KCAN_STAT_IDLE BIT(10)
171 /* Bus off */
172 #define KVASER_PCIEFD_KCAN_STAT_BOFF BIT(11)
173 /* Reset mode request */
174 #define KVASER_PCIEFD_KCAN_STAT_RMR BIT(14)
175 /* Controller in reset mode */
176 #define KVASER_PCIEFD_KCAN_STAT_IRM BIT(15)
177 /* Controller got one-shot capability */
178 #define KVASER_PCIEFD_KCAN_STAT_CAP BIT(16)
179 /* Controller got CAN FD capability */
180 #define KVASER_PCIEFD_KCAN_STAT_FD BIT(19)
181 #define KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK (KVASER_PCIEFD_KCAN_STAT_AR | \
182 	KVASER_PCIEFD_KCAN_STAT_BOFF | KVASER_PCIEFD_KCAN_STAT_RMR | \
183 	KVASER_PCIEFD_KCAN_STAT_IRM)
184 
185 /* Reset mode */
186 #define KVASER_PCIEFD_KCAN_MODE_RM BIT(8)
187 /* Listen only mode */
188 #define KVASER_PCIEFD_KCAN_MODE_LOM BIT(9)
189 /* Error packet enable */
190 #define KVASER_PCIEFD_KCAN_MODE_EPEN BIT(12)
191 /* CAN FD non-ISO */
192 #define KVASER_PCIEFD_KCAN_MODE_NIFDEN BIT(15)
193 /* Acknowledgment packet type */
194 #define KVASER_PCIEFD_KCAN_MODE_APT BIT(20)
195 /* Active error flag enable. Clear to force error passive */
196 #define KVASER_PCIEFD_KCAN_MODE_EEN BIT(23)
197 /* Classic CAN mode */
198 #define KVASER_PCIEFD_KCAN_MODE_CCM BIT(31)
199 
200 #define KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT 13
201 #define KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT 17
202 #define KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT 26
203 
204 #define KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT 16
205 
206 /* Kvaser KCAN packet types */
207 #define KVASER_PCIEFD_PACK_TYPE_DATA 0
208 #define KVASER_PCIEFD_PACK_TYPE_ACK 1
209 #define KVASER_PCIEFD_PACK_TYPE_TXRQ 2
210 #define KVASER_PCIEFD_PACK_TYPE_ERROR 3
211 #define KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK 4
212 #define KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK 5
213 #define KVASER_PCIEFD_PACK_TYPE_ACK_DATA 6
214 #define KVASER_PCIEFD_PACK_TYPE_STATUS 8
215 #define KVASER_PCIEFD_PACK_TYPE_BUS_LOAD 9
216 
217 /* Kvaser KCAN packet common definitions */
218 #define KVASER_PCIEFD_PACKET_SEQ_MSK 0xff
219 #define KVASER_PCIEFD_PACKET_CHID_SHIFT 25
220 #define KVASER_PCIEFD_PACKET_TYPE_SHIFT 28
221 
222 /* Kvaser KCAN TDATA and RDATA first word */
223 #define KVASER_PCIEFD_RPACKET_IDE BIT(30)
224 #define KVASER_PCIEFD_RPACKET_RTR BIT(29)
225 /* Kvaser KCAN TDATA and RDATA second word */
226 #define KVASER_PCIEFD_RPACKET_ESI BIT(13)
227 #define KVASER_PCIEFD_RPACKET_BRS BIT(14)
228 #define KVASER_PCIEFD_RPACKET_FDF BIT(15)
229 #define KVASER_PCIEFD_RPACKET_DLC_SHIFT 8
230 /* Kvaser KCAN TDATA second word */
231 #define KVASER_PCIEFD_TPACKET_SMS BIT(16)
232 #define KVASER_PCIEFD_TPACKET_AREQ BIT(31)
233 
234 /* Kvaser KCAN APACKET */
235 #define KVASER_PCIEFD_APACKET_FLU BIT(8)
236 #define KVASER_PCIEFD_APACKET_CT BIT(9)
237 #define KVASER_PCIEFD_APACKET_ABL BIT(10)
238 #define KVASER_PCIEFD_APACKET_NACK BIT(11)
239 
240 /* Kvaser KCAN SPACK first word */
241 #define KVASER_PCIEFD_SPACK_RXERR_SHIFT 8
242 #define KVASER_PCIEFD_SPACK_BOFF BIT(16)
243 #define KVASER_PCIEFD_SPACK_IDET BIT(20)
244 #define KVASER_PCIEFD_SPACK_IRM BIT(21)
245 #define KVASER_PCIEFD_SPACK_RMCD BIT(22)
246 /* Kvaser KCAN SPACK second word */
247 #define KVASER_PCIEFD_SPACK_AUTO BIT(21)
248 #define KVASER_PCIEFD_SPACK_EWLR BIT(23)
249 #define KVASER_PCIEFD_SPACK_EPLR BIT(24)
250 
251 /* Kvaser KCAN_EPACK second word */
252 #define KVASER_PCIEFD_EPACK_DIR_TX BIT(0)
253 
254 struct kvaser_pciefd;
255 
256 struct kvaser_pciefd_can {
257 	struct can_priv can;
258 	struct kvaser_pciefd *kv_pcie;
259 	void __iomem *reg_base;
260 	struct can_berr_counter bec;
261 	u8 cmd_seq;
262 	int err_rep_cnt;
263 	int echo_idx;
264 	spinlock_t lock; /* Locks sensitive registers (e.g. MODE) */
265 	spinlock_t echo_lock; /* Locks the message echo buffer */
266 	struct timer_list bec_poll_timer;
267 	struct completion start_comp, flush_comp;
268 };
269 
270 struct kvaser_pciefd {
271 	struct pci_dev *pci;
272 	void __iomem *reg_base;
273 	struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
274 	void *dma_data[KVASER_PCIEFD_DMA_COUNT];
275 	u8 nr_channels;
276 	u32 bus_freq;
277 	u32 freq;
278 	u32 freq_to_ticks_div;
279 };
280 
281 struct kvaser_pciefd_rx_packet {
282 	u32 header[2];
283 	u64 timestamp;
284 };
285 
286 struct kvaser_pciefd_tx_packet {
287 	u32 header[2];
288 	u8 data[64];
289 };
290 
291 static const struct can_bittiming_const kvaser_pciefd_bittiming_const = {
292 	.name = KVASER_PCIEFD_DRV_NAME,
293 	.tseg1_min = 1,
294 	.tseg1_max = 512,
295 	.tseg2_min = 1,
296 	.tseg2_max = 32,
297 	.sjw_max = 16,
298 	.brp_min = 1,
299 	.brp_max = 8192,
300 	.brp_inc = 1,
301 };
302 
303 struct kvaser_pciefd_cfg_param {
304 	__le32 magic;
305 	__le32 nr;
306 	__le32 len;
307 	u8 data[KVASER_PCIEFD_CFG_PARAM_MAX_SZ];
308 };
309 
310 struct kvaser_pciefd_cfg_img {
311 	__le32 version;
312 	__le32 magic;
313 	__le32 crc;
314 	struct kvaser_pciefd_cfg_param params[KVASER_PCIEFD_CFG_MAX_PARAMS];
315 };
316 
317 static struct pci_device_id kvaser_pciefd_id_table[] = {
318 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_4HS_ID), },
319 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_2HS_ID), },
320 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_HS_ID), },
321 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_HS_ID), },
322 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_2HS_ID), },
323 	{ 0,},
324 };
325 MODULE_DEVICE_TABLE(pci, kvaser_pciefd_id_table);
326 
327 /* Onboard flash memory functions */
328 static int kvaser_pciefd_spi_wait_loop(struct kvaser_pciefd *pcie, int msk)
329 {
330 	u32 res;
331 	int ret;
332 
333 	ret = readl_poll_timeout(pcie->reg_base + KVASER_PCIEFD_SPI_STATUS_REG,
334 				 res, res & msk, 0, 10);
335 
336 	return ret;
337 }
338 
339 static int kvaser_pciefd_spi_cmd(struct kvaser_pciefd *pcie, const u8 *tx,
340 				 u32 tx_len, u8 *rx, u32 rx_len)
341 {
342 	int c;
343 
344 	iowrite32(BIT(0), pcie->reg_base + KVASER_PCIEFD_SPI_SSEL_REG);
345 	iowrite32(BIT(10), pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
346 	ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
347 
348 	c = tx_len;
349 	while (c--) {
350 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
351 			return -EIO;
352 
353 		iowrite32(*tx++, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
354 
355 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
356 			return -EIO;
357 
358 		ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
359 	}
360 
361 	c = rx_len;
362 	while (c-- > 0) {
363 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
364 			return -EIO;
365 
366 		iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
367 
368 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
369 			return -EIO;
370 
371 		*rx++ = ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
372 	}
373 
374 	if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TMT))
375 		return -EIO;
376 
377 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
378 
379 	if (c != -1) {
380 		dev_err(&pcie->pci->dev, "Flash SPI transfer failed\n");
381 		return -EIO;
382 	}
383 
384 	return 0;
385 }
386 
387 static int kvaser_pciefd_cfg_read_and_verify(struct kvaser_pciefd *pcie,
388 					     struct kvaser_pciefd_cfg_img *img)
389 {
390 	int offset = KVASER_PCIEFD_CFG_IMG_OFFSET;
391 	int res, crc;
392 	u8 *crc_buff;
393 
394 	u8 cmd[] = {
395 		KVASER_PCIEFD_FLASH_READ_CMD,
396 		(u8)((offset >> 16) & 0xff),
397 		(u8)((offset >> 8) & 0xff),
398 		(u8)(offset & 0xff)
399 	};
400 
401 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), (u8 *)img,
402 				    KVASER_PCIEFD_CFG_IMG_SZ);
403 	if (res)
404 		return res;
405 
406 	crc_buff = (u8 *)img->params;
407 
408 	if (le32_to_cpu(img->version) != KVASER_PCIEFD_CFG_SYS_VER) {
409 		dev_err(&pcie->pci->dev,
410 			"Config flash corrupted, version number is wrong\n");
411 		return -ENODEV;
412 	}
413 
414 	if (le32_to_cpu(img->magic) != KVASER_PCIEFD_CFG_MAGIC) {
415 		dev_err(&pcie->pci->dev,
416 			"Config flash corrupted, magic number is wrong\n");
417 		return -ENODEV;
418 	}
419 
420 	crc = ~crc32_be(0xffffffff, crc_buff, sizeof(img->params));
421 	if (le32_to_cpu(img->crc) != crc) {
422 		dev_err(&pcie->pci->dev,
423 			"Stored CRC does not match flash image contents\n");
424 		return -EIO;
425 	}
426 
427 	return 0;
428 }
429 
430 static void kvaser_pciefd_cfg_read_params(struct kvaser_pciefd *pcie,
431 					  struct kvaser_pciefd_cfg_img *img)
432 {
433 	struct kvaser_pciefd_cfg_param *param;
434 
435 	param = &img->params[KVASER_PCIEFD_CFG_PARAM_NR_CHAN];
436 	memcpy(&pcie->nr_channels, param->data, le32_to_cpu(param->len));
437 }
438 
439 static int kvaser_pciefd_read_cfg(struct kvaser_pciefd *pcie)
440 {
441 	int res;
442 	struct kvaser_pciefd_cfg_img *img;
443 
444 	/* Read electronic signature */
445 	u8 cmd[] = {KVASER_PCIEFD_FLASH_RES_CMD, 0, 0, 0};
446 
447 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), cmd, 1);
448 	if (res)
449 		return -EIO;
450 
451 	img = kmalloc(KVASER_PCIEFD_CFG_IMG_SZ, GFP_KERNEL);
452 	if (!img)
453 		return -ENOMEM;
454 
455 	if (cmd[0] != KVASER_PCIEFD_FLASH_ID_EPCS16) {
456 		dev_err(&pcie->pci->dev,
457 			"Flash id is 0x%x instead of expected EPCS16 (0x%x)\n",
458 			cmd[0], KVASER_PCIEFD_FLASH_ID_EPCS16);
459 
460 		res = -ENODEV;
461 		goto image_free;
462 	}
463 
464 	cmd[0] = KVASER_PCIEFD_FLASH_STATUS_CMD;
465 	res = kvaser_pciefd_spi_cmd(pcie, cmd, 1, cmd, 1);
466 	if (res) {
467 		goto image_free;
468 	} else if (cmd[0] & 1) {
469 		res = -EIO;
470 		/* No write is ever done, the WIP should never be set */
471 		dev_err(&pcie->pci->dev, "Unexpected WIP bit set in flash\n");
472 		goto image_free;
473 	}
474 
475 	res = kvaser_pciefd_cfg_read_and_verify(pcie, img);
476 	if (res) {
477 		res = -EIO;
478 		goto image_free;
479 	}
480 
481 	kvaser_pciefd_cfg_read_params(pcie, img);
482 
483 image_free:
484 	kfree(img);
485 	return res;
486 }
487 
488 static void kvaser_pciefd_request_status(struct kvaser_pciefd_can *can)
489 {
490 	u32 cmd;
491 
492 	cmd = KVASER_PCIEFD_KCAN_CMD_SRQ;
493 	cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
494 	iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
495 }
496 
497 static void kvaser_pciefd_enable_err_gen(struct kvaser_pciefd_can *can)
498 {
499 	u32 mode;
500 	unsigned long irq;
501 
502 	spin_lock_irqsave(&can->lock, irq);
503 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
504 	if (!(mode & KVASER_PCIEFD_KCAN_MODE_EPEN)) {
505 		mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
506 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
507 	}
508 	spin_unlock_irqrestore(&can->lock, irq);
509 }
510 
511 static void kvaser_pciefd_disable_err_gen(struct kvaser_pciefd_can *can)
512 {
513 	u32 mode;
514 	unsigned long irq;
515 
516 	spin_lock_irqsave(&can->lock, irq);
517 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
518 	mode &= ~KVASER_PCIEFD_KCAN_MODE_EPEN;
519 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
520 	spin_unlock_irqrestore(&can->lock, irq);
521 }
522 
523 static int kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
524 {
525 	u32 msk;
526 
527 	msk = KVASER_PCIEFD_KCAN_IRQ_TE | KVASER_PCIEFD_KCAN_IRQ_ROF |
528 	      KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD |
529 	      KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL |
530 	      KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP |
531 	      KVASER_PCIEFD_KCAN_IRQ_TAR | KVASER_PCIEFD_KCAN_IRQ_TFD;
532 
533 	iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
534 
535 	return 0;
536 }
537 
538 static void kvaser_pciefd_setup_controller(struct kvaser_pciefd_can *can)
539 {
540 	u32 mode;
541 	unsigned long irq;
542 
543 	spin_lock_irqsave(&can->lock, irq);
544 
545 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
546 	if (can->can.ctrlmode & CAN_CTRLMODE_FD) {
547 		mode &= ~KVASER_PCIEFD_KCAN_MODE_CCM;
548 		if (can->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
549 			mode |= KVASER_PCIEFD_KCAN_MODE_NIFDEN;
550 		else
551 			mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
552 	} else {
553 		mode |= KVASER_PCIEFD_KCAN_MODE_CCM;
554 		mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
555 	}
556 
557 	if (can->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
558 		mode |= KVASER_PCIEFD_KCAN_MODE_LOM;
559 
560 	mode |= KVASER_PCIEFD_KCAN_MODE_EEN;
561 	mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
562 	/* Use ACK packet type */
563 	mode &= ~KVASER_PCIEFD_KCAN_MODE_APT;
564 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
565 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
566 
567 	spin_unlock_irqrestore(&can->lock, irq);
568 }
569 
570 static void kvaser_pciefd_start_controller_flush(struct kvaser_pciefd_can *can)
571 {
572 	u32 status;
573 	unsigned long irq;
574 
575 	spin_lock_irqsave(&can->lock, irq);
576 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
577 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
578 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
579 
580 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
581 	if (status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
582 		u32 cmd;
583 
584 		/* If controller is already idle, run abort, flush and reset */
585 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
586 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
587 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
588 	} else if (!(status & KVASER_PCIEFD_KCAN_STAT_RMR)) {
589 		u32 mode;
590 
591 		/* Put controller in reset mode */
592 		mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
593 		mode |= KVASER_PCIEFD_KCAN_MODE_RM;
594 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
595 	}
596 
597 	spin_unlock_irqrestore(&can->lock, irq);
598 }
599 
600 static int kvaser_pciefd_bus_on(struct kvaser_pciefd_can *can)
601 {
602 	u32 mode;
603 	unsigned long irq;
604 
605 	del_timer(&can->bec_poll_timer);
606 
607 	if (!completion_done(&can->flush_comp))
608 		kvaser_pciefd_start_controller_flush(can);
609 
610 	if (!wait_for_completion_timeout(&can->flush_comp,
611 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
612 		netdev_err(can->can.dev, "Timeout during bus on flush\n");
613 		return -ETIMEDOUT;
614 	}
615 
616 	spin_lock_irqsave(&can->lock, irq);
617 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
618 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
619 
620 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
621 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
622 
623 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
624 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
625 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
626 	spin_unlock_irqrestore(&can->lock, irq);
627 
628 	if (!wait_for_completion_timeout(&can->start_comp,
629 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
630 		netdev_err(can->can.dev, "Timeout during bus on reset\n");
631 		return -ETIMEDOUT;
632 	}
633 	/* Reset interrupt handling */
634 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
635 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
636 
637 	kvaser_pciefd_set_tx_irq(can);
638 	kvaser_pciefd_setup_controller(can);
639 
640 	can->can.state = CAN_STATE_ERROR_ACTIVE;
641 	netif_wake_queue(can->can.dev);
642 	can->bec.txerr = 0;
643 	can->bec.rxerr = 0;
644 	can->err_rep_cnt = 0;
645 
646 	return 0;
647 }
648 
649 static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
650 {
651 	u8 top;
652 	u32 pwm_ctrl;
653 	unsigned long irq;
654 
655 	spin_lock_irqsave(&can->lock, irq);
656 	pwm_ctrl = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
657 	top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;
658 
659 	/* Set duty cycle to zero */
660 	pwm_ctrl |= top;
661 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
662 	spin_unlock_irqrestore(&can->lock, irq);
663 }
664 
665 static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
666 {
667 	int top, trigger;
668 	u32 pwm_ctrl;
669 	unsigned long irq;
670 
671 	kvaser_pciefd_pwm_stop(can);
672 	spin_lock_irqsave(&can->lock, irq);
673 
674 	/* Set frequency to 500 KHz*/
675 	top = can->kv_pcie->bus_freq / (2 * 500000) - 1;
676 
677 	pwm_ctrl = top & 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 
681 	/* Set duty cycle to 95 */
682 	trigger = (100 * top - 95 * (top + 1) + 50) / 100;
683 	pwm_ctrl = trigger & 0xff;
684 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
685 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
686 	spin_unlock_irqrestore(&can->lock, irq);
687 }
688 
689 static int kvaser_pciefd_open(struct net_device *netdev)
690 {
691 	int err;
692 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
693 
694 	err = open_candev(netdev);
695 	if (err)
696 		return err;
697 
698 	err = kvaser_pciefd_bus_on(can);
699 	if (err) {
700 		close_candev(netdev);
701 		return err;
702 	}
703 
704 	return 0;
705 }
706 
707 static int kvaser_pciefd_stop(struct net_device *netdev)
708 {
709 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
710 	int ret = 0;
711 
712 	/* Don't interrupt ongoing flush */
713 	if (!completion_done(&can->flush_comp))
714 		kvaser_pciefd_start_controller_flush(can);
715 
716 	if (!wait_for_completion_timeout(&can->flush_comp,
717 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
718 		netdev_err(can->can.dev, "Timeout during stop\n");
719 		ret = -ETIMEDOUT;
720 	} else {
721 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
722 		del_timer(&can->bec_poll_timer);
723 	}
724 	close_candev(netdev);
725 
726 	return ret;
727 }
728 
729 static int kvaser_pciefd_prepare_tx_packet(struct kvaser_pciefd_tx_packet *p,
730 					   struct kvaser_pciefd_can *can,
731 					   struct sk_buff *skb)
732 {
733 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
734 	int packet_size;
735 	int seq = can->echo_idx;
736 
737 	memset(p, 0, sizeof(*p));
738 
739 	if (can->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
740 		p->header[1] |= KVASER_PCIEFD_TPACKET_SMS;
741 
742 	if (cf->can_id & CAN_RTR_FLAG)
743 		p->header[0] |= KVASER_PCIEFD_RPACKET_RTR;
744 
745 	if (cf->can_id & CAN_EFF_FLAG)
746 		p->header[0] |= KVASER_PCIEFD_RPACKET_IDE;
747 
748 	p->header[0] |= cf->can_id & CAN_EFF_MASK;
749 	p->header[1] |= can_fd_len2dlc(cf->len) << KVASER_PCIEFD_RPACKET_DLC_SHIFT;
750 	p->header[1] |= KVASER_PCIEFD_TPACKET_AREQ;
751 
752 	if (can_is_canfd_skb(skb)) {
753 		p->header[1] |= KVASER_PCIEFD_RPACKET_FDF;
754 		if (cf->flags & CANFD_BRS)
755 			p->header[1] |= KVASER_PCIEFD_RPACKET_BRS;
756 		if (cf->flags & CANFD_ESI)
757 			p->header[1] |= KVASER_PCIEFD_RPACKET_ESI;
758 	}
759 
760 	p->header[1] |= seq & KVASER_PCIEFD_PACKET_SEQ_MSK;
761 
762 	packet_size = cf->len;
763 	memcpy(p->data, cf->data, packet_size);
764 
765 	return DIV_ROUND_UP(packet_size, 4);
766 }
767 
768 static netdev_tx_t kvaser_pciefd_start_xmit(struct sk_buff *skb,
769 					    struct net_device *netdev)
770 {
771 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
772 	unsigned long irq_flags;
773 	struct kvaser_pciefd_tx_packet packet;
774 	int nwords;
775 	u8 count;
776 
777 	if (can_dropped_invalid_skb(netdev, skb))
778 		return NETDEV_TX_OK;
779 
780 	nwords = kvaser_pciefd_prepare_tx_packet(&packet, can, skb);
781 
782 	spin_lock_irqsave(&can->echo_lock, irq_flags);
783 
784 	/* Prepare and save echo skb in internal slot */
785 	can_put_echo_skb(skb, netdev, can->echo_idx, 0);
786 
787 	/* Move echo index to the next slot */
788 	can->echo_idx = (can->echo_idx + 1) % can->can.echo_skb_max;
789 
790 	/* Write header to fifo */
791 	iowrite32(packet.header[0],
792 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
793 	iowrite32(packet.header[1],
794 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
795 
796 	if (nwords) {
797 		u32 data_last = ((u32 *)packet.data)[nwords - 1];
798 
799 		/* Write data to fifo, except last word */
800 		iowrite32_rep(can->reg_base +
801 			      KVASER_PCIEFD_KCAN_FIFO_REG, packet.data,
802 			      nwords - 1);
803 		/* Write last word to end of fifo */
804 		__raw_writel(data_last, can->reg_base +
805 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
806 	} else {
807 		/* Complete write to fifo */
808 		__raw_writel(0, can->reg_base +
809 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
810 	}
811 
812 	count = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
813 	/* No room for a new message, stop the queue until at least one
814 	 * successful transmit
815 	 */
816 	if (count >= KVASER_PCIEFD_CAN_TX_MAX_COUNT ||
817 	    can->can.echo_skb[can->echo_idx])
818 		netif_stop_queue(netdev);
819 
820 	spin_unlock_irqrestore(&can->echo_lock, irq_flags);
821 
822 	return NETDEV_TX_OK;
823 }
824 
825 static int kvaser_pciefd_set_bittiming(struct kvaser_pciefd_can *can, bool data)
826 {
827 	u32 mode, test, btrn;
828 	unsigned long irq_flags;
829 	int ret;
830 	struct can_bittiming *bt;
831 
832 	if (data)
833 		bt = &can->can.data_bittiming;
834 	else
835 		bt = &can->can.bittiming;
836 
837 	btrn = ((bt->phase_seg2 - 1) & 0x1f) <<
838 	       KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT |
839 	       (((bt->prop_seg + bt->phase_seg1) - 1) & 0x1ff) <<
840 	       KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT |
841 	       ((bt->sjw - 1) & 0xf) << KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT |
842 	       ((bt->brp - 1) & 0x1fff);
843 
844 	spin_lock_irqsave(&can->lock, irq_flags);
845 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
846 
847 	/* Put the circuit in reset mode */
848 	iowrite32(mode | KVASER_PCIEFD_KCAN_MODE_RM,
849 		  can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
850 
851 	/* Can only set bittiming if in reset mode */
852 	ret = readl_poll_timeout(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG,
853 				 test, test & KVASER_PCIEFD_KCAN_MODE_RM,
854 				 0, 10);
855 
856 	if (ret) {
857 		spin_unlock_irqrestore(&can->lock, irq_flags);
858 		return -EBUSY;
859 	}
860 
861 	if (data)
862 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRD_REG);
863 	else
864 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRN_REG);
865 
866 	/* Restore previous reset mode status */
867 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
868 
869 	spin_unlock_irqrestore(&can->lock, irq_flags);
870 	return 0;
871 }
872 
873 static int kvaser_pciefd_set_nominal_bittiming(struct net_device *ndev)
874 {
875 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), false);
876 }
877 
878 static int kvaser_pciefd_set_data_bittiming(struct net_device *ndev)
879 {
880 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), true);
881 }
882 
883 static int kvaser_pciefd_set_mode(struct net_device *ndev, enum can_mode mode)
884 {
885 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
886 	int ret = 0;
887 
888 	switch (mode) {
889 	case CAN_MODE_START:
890 		if (!can->can.restart_ms)
891 			ret = kvaser_pciefd_bus_on(can);
892 		break;
893 	default:
894 		return -EOPNOTSUPP;
895 	}
896 
897 	return ret;
898 }
899 
900 static int kvaser_pciefd_get_berr_counter(const struct net_device *ndev,
901 					  struct can_berr_counter *bec)
902 {
903 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
904 
905 	bec->rxerr = can->bec.rxerr;
906 	bec->txerr = can->bec.txerr;
907 	return 0;
908 }
909 
910 static void kvaser_pciefd_bec_poll_timer(struct timer_list *data)
911 {
912 	struct kvaser_pciefd_can *can = from_timer(can, data, bec_poll_timer);
913 
914 	kvaser_pciefd_enable_err_gen(can);
915 	kvaser_pciefd_request_status(can);
916 	can->err_rep_cnt = 0;
917 }
918 
919 static const struct net_device_ops kvaser_pciefd_netdev_ops = {
920 	.ndo_open = kvaser_pciefd_open,
921 	.ndo_stop = kvaser_pciefd_stop,
922 	.ndo_start_xmit = kvaser_pciefd_start_xmit,
923 	.ndo_change_mtu = can_change_mtu,
924 };
925 
926 static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
927 {
928 	int i;
929 
930 	for (i = 0; i < pcie->nr_channels; i++) {
931 		struct net_device *netdev;
932 		struct kvaser_pciefd_can *can;
933 		u32 status, tx_npackets;
934 
935 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
936 				      KVASER_PCIEFD_CAN_TX_MAX_COUNT);
937 		if (!netdev)
938 			return -ENOMEM;
939 
940 		can = netdev_priv(netdev);
941 		netdev->netdev_ops = &kvaser_pciefd_netdev_ops;
942 		can->reg_base = pcie->reg_base + KVASER_PCIEFD_KCAN0_BASE +
943 				i * KVASER_PCIEFD_KCAN_BASE_OFFSET;
944 
945 		can->kv_pcie = pcie;
946 		can->cmd_seq = 0;
947 		can->err_rep_cnt = 0;
948 		can->bec.txerr = 0;
949 		can->bec.rxerr = 0;
950 
951 		init_completion(&can->start_comp);
952 		init_completion(&can->flush_comp);
953 		timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer,
954 			    0);
955 
956 		/* Disable Bus load reporting */
957 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_BUS_LOAD_REG);
958 
959 		tx_npackets = ioread32(can->reg_base +
960 				       KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
961 		if (((tx_npackets >> KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT) &
962 		      0xff) < KVASER_PCIEFD_CAN_TX_MAX_COUNT) {
963 			dev_err(&pcie->pci->dev,
964 				"Max Tx count is smaller than expected\n");
965 
966 			free_candev(netdev);
967 			return -ENODEV;
968 		}
969 
970 		can->can.clock.freq = pcie->freq;
971 		can->can.echo_skb_max = KVASER_PCIEFD_CAN_TX_MAX_COUNT;
972 		can->echo_idx = 0;
973 		spin_lock_init(&can->echo_lock);
974 		spin_lock_init(&can->lock);
975 		can->can.bittiming_const = &kvaser_pciefd_bittiming_const;
976 		can->can.data_bittiming_const = &kvaser_pciefd_bittiming_const;
977 
978 		can->can.do_set_bittiming = kvaser_pciefd_set_nominal_bittiming;
979 		can->can.do_set_data_bittiming =
980 			kvaser_pciefd_set_data_bittiming;
981 
982 		can->can.do_set_mode = kvaser_pciefd_set_mode;
983 		can->can.do_get_berr_counter = kvaser_pciefd_get_berr_counter;
984 
985 		can->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
986 					      CAN_CTRLMODE_FD |
987 					      CAN_CTRLMODE_FD_NON_ISO;
988 
989 		status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
990 		if (!(status & KVASER_PCIEFD_KCAN_STAT_FD)) {
991 			dev_err(&pcie->pci->dev,
992 				"CAN FD not supported as expected %d\n", i);
993 
994 			free_candev(netdev);
995 			return -ENODEV;
996 		}
997 
998 		if (status & KVASER_PCIEFD_KCAN_STAT_CAP)
999 			can->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1000 
1001 		netdev->flags |= IFF_ECHO;
1002 
1003 		SET_NETDEV_DEV(netdev, &pcie->pci->dev);
1004 
1005 		iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1006 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD |
1007 			  KVASER_PCIEFD_KCAN_IRQ_TFD,
1008 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1009 
1010 		pcie->can[i] = can;
1011 		kvaser_pciefd_pwm_start(can);
1012 	}
1013 
1014 	return 0;
1015 }
1016 
1017 static int kvaser_pciefd_reg_candev(struct kvaser_pciefd *pcie)
1018 {
1019 	int i;
1020 
1021 	for (i = 0; i < pcie->nr_channels; i++) {
1022 		int err = register_candev(pcie->can[i]->can.dev);
1023 
1024 		if (err) {
1025 			int j;
1026 
1027 			/* Unregister all successfully registered devices. */
1028 			for (j = 0; j < i; j++)
1029 				unregister_candev(pcie->can[j]->can.dev);
1030 			return err;
1031 		}
1032 	}
1033 
1034 	return 0;
1035 }
1036 
1037 static void kvaser_pciefd_write_dma_map(struct kvaser_pciefd *pcie,
1038 					dma_addr_t addr, int offset)
1039 {
1040 	u32 word1, word2;
1041 
1042 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
1043 	word1 = addr | KVASER_PCIEFD_64BIT_DMA_BIT;
1044 	word2 = addr >> 32;
1045 #else
1046 	word1 = addr;
1047 	word2 = 0;
1048 #endif
1049 	iowrite32(word1, pcie->reg_base + offset);
1050 	iowrite32(word2, pcie->reg_base + offset + 4);
1051 }
1052 
1053 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
1054 {
1055 	int i;
1056 	u32 srb_status;
1057 	dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
1058 
1059 	/* Disable the DMA */
1060 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1061 	for (i = 0; i < KVASER_PCIEFD_DMA_COUNT; i++) {
1062 		unsigned int offset = KVASER_PCIEFD_DMA_MAP_BASE + 8 * i;
1063 
1064 		pcie->dma_data[i] =
1065 			dmam_alloc_coherent(&pcie->pci->dev,
1066 					    KVASER_PCIEFD_DMA_SIZE,
1067 					    &dma_addr[i],
1068 					    GFP_KERNEL);
1069 
1070 		if (!pcie->dma_data[i] || !dma_addr[i]) {
1071 			dev_err(&pcie->pci->dev, "Rx dma_alloc(%u) failure\n",
1072 				KVASER_PCIEFD_DMA_SIZE);
1073 			return -ENOMEM;
1074 		}
1075 
1076 		kvaser_pciefd_write_dma_map(pcie, dma_addr[i], offset);
1077 	}
1078 
1079 	/* Reset Rx FIFO, and both DMA buffers */
1080 	iowrite32(KVASER_PCIEFD_SRB_CMD_FOR | KVASER_PCIEFD_SRB_CMD_RDB0 |
1081 		  KVASER_PCIEFD_SRB_CMD_RDB1,
1082 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1083 
1084 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1085 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
1086 		dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
1087 		return -EIO;
1088 	}
1089 
1090 	/* Enable the DMA */
1091 	iowrite32(KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE,
1092 		  pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1093 
1094 	return 0;
1095 }
1096 
1097 static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
1098 {
1099 	u32 sysid, srb_status, build;
1100 	u8 sysid_nr_chan;
1101 	int ret;
1102 
1103 	ret = kvaser_pciefd_read_cfg(pcie);
1104 	if (ret)
1105 		return ret;
1106 
1107 	sysid = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_VERSION_REG);
1108 	sysid_nr_chan = (sysid >> KVASER_PCIEFD_SYSID_NRCHAN_SHIFT) & 0xff;
1109 	if (pcie->nr_channels != sysid_nr_chan) {
1110 		dev_err(&pcie->pci->dev,
1111 			"Number of channels does not match: %u vs %u\n",
1112 			pcie->nr_channels,
1113 			sysid_nr_chan);
1114 		return -ENODEV;
1115 	}
1116 
1117 	if (pcie->nr_channels > KVASER_PCIEFD_MAX_CAN_CHANNELS)
1118 		pcie->nr_channels = KVASER_PCIEFD_MAX_CAN_CHANNELS;
1119 
1120 	build = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_BUILD_REG);
1121 	dev_dbg(&pcie->pci->dev, "Version %u.%u.%u\n",
1122 		(sysid >> KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT) & 0xff,
1123 		sysid & 0xff,
1124 		(build >> KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT) & 0x7fff);
1125 
1126 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1127 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DMA)) {
1128 		dev_err(&pcie->pci->dev,
1129 			"Hardware without DMA is not supported\n");
1130 		return -ENODEV;
1131 	}
1132 
1133 	pcie->bus_freq = ioread32(pcie->reg_base +
1134 				  KVASER_PCIEFD_SYSID_BUSFREQ_REG);
1135 	pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
1136 	pcie->freq_to_ticks_div = pcie->freq / 1000000;
1137 	if (pcie->freq_to_ticks_div == 0)
1138 		pcie->freq_to_ticks_div = 1;
1139 
1140 	/* Turn off all loopback functionality */
1141 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_LOOP_REG);
1142 	return ret;
1143 }
1144 
1145 static int kvaser_pciefd_handle_data_packet(struct kvaser_pciefd *pcie,
1146 					    struct kvaser_pciefd_rx_packet *p,
1147 					    __le32 *data)
1148 {
1149 	struct sk_buff *skb;
1150 	struct canfd_frame *cf;
1151 	struct can_priv *priv;
1152 	struct net_device_stats *stats;
1153 	struct skb_shared_hwtstamps *shhwtstamps;
1154 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1155 
1156 	if (ch_id >= pcie->nr_channels)
1157 		return -EIO;
1158 
1159 	priv = &pcie->can[ch_id]->can;
1160 	stats = &priv->dev->stats;
1161 
1162 	if (p->header[1] & KVASER_PCIEFD_RPACKET_FDF) {
1163 		skb = alloc_canfd_skb(priv->dev, &cf);
1164 		if (!skb) {
1165 			stats->rx_dropped++;
1166 			return -ENOMEM;
1167 		}
1168 
1169 		if (p->header[1] & KVASER_PCIEFD_RPACKET_BRS)
1170 			cf->flags |= CANFD_BRS;
1171 
1172 		if (p->header[1] & KVASER_PCIEFD_RPACKET_ESI)
1173 			cf->flags |= CANFD_ESI;
1174 	} else {
1175 		skb = alloc_can_skb(priv->dev, (struct can_frame **)&cf);
1176 		if (!skb) {
1177 			stats->rx_dropped++;
1178 			return -ENOMEM;
1179 		}
1180 	}
1181 
1182 	cf->can_id = p->header[0] & CAN_EFF_MASK;
1183 	if (p->header[0] & KVASER_PCIEFD_RPACKET_IDE)
1184 		cf->can_id |= CAN_EFF_FLAG;
1185 
1186 	cf->len = can_fd_dlc2len(p->header[1] >> KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1187 
1188 	if (p->header[0] & KVASER_PCIEFD_RPACKET_RTR) {
1189 		cf->can_id |= CAN_RTR_FLAG;
1190 	} else {
1191 		memcpy(cf->data, data, cf->len);
1192 
1193 		stats->rx_bytes += cf->len;
1194 	}
1195 	stats->rx_packets++;
1196 
1197 	shhwtstamps = skb_hwtstamps(skb);
1198 
1199 	shhwtstamps->hwtstamp =
1200 		ns_to_ktime(div_u64(p->timestamp * 1000,
1201 				    pcie->freq_to_ticks_div));
1202 
1203 	return netif_rx(skb);
1204 }
1205 
1206 static void kvaser_pciefd_change_state(struct kvaser_pciefd_can *can,
1207 				       struct can_frame *cf,
1208 				       enum can_state new_state,
1209 				       enum can_state tx_state,
1210 				       enum can_state rx_state)
1211 {
1212 	can_change_state(can->can.dev, cf, tx_state, rx_state);
1213 
1214 	if (new_state == CAN_STATE_BUS_OFF) {
1215 		struct net_device *ndev = can->can.dev;
1216 		unsigned long irq_flags;
1217 
1218 		spin_lock_irqsave(&can->lock, irq_flags);
1219 		netif_stop_queue(can->can.dev);
1220 		spin_unlock_irqrestore(&can->lock, irq_flags);
1221 
1222 		/* Prevent CAN controller from auto recover from bus off */
1223 		if (!can->can.restart_ms) {
1224 			kvaser_pciefd_start_controller_flush(can);
1225 			can_bus_off(ndev);
1226 		}
1227 	}
1228 }
1229 
1230 static void kvaser_pciefd_packet_to_state(struct kvaser_pciefd_rx_packet *p,
1231 					  struct can_berr_counter *bec,
1232 					  enum can_state *new_state,
1233 					  enum can_state *tx_state,
1234 					  enum can_state *rx_state)
1235 {
1236 	if (p->header[0] & KVASER_PCIEFD_SPACK_BOFF ||
1237 	    p->header[0] & KVASER_PCIEFD_SPACK_IRM)
1238 		*new_state = CAN_STATE_BUS_OFF;
1239 	else if (bec->txerr >= 255 ||  bec->rxerr >= 255)
1240 		*new_state = CAN_STATE_BUS_OFF;
1241 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EPLR)
1242 		*new_state = CAN_STATE_ERROR_PASSIVE;
1243 	else if (bec->txerr >= 128 || bec->rxerr >= 128)
1244 		*new_state = CAN_STATE_ERROR_PASSIVE;
1245 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EWLR)
1246 		*new_state = CAN_STATE_ERROR_WARNING;
1247 	else if (bec->txerr >= 96 || bec->rxerr >= 96)
1248 		*new_state = CAN_STATE_ERROR_WARNING;
1249 	else
1250 		*new_state = CAN_STATE_ERROR_ACTIVE;
1251 
1252 	*tx_state = bec->txerr >= bec->rxerr ? *new_state : 0;
1253 	*rx_state = bec->txerr <= bec->rxerr ? *new_state : 0;
1254 }
1255 
1256 static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
1257 					struct kvaser_pciefd_rx_packet *p)
1258 {
1259 	struct can_berr_counter bec;
1260 	enum can_state old_state, new_state, tx_state, rx_state;
1261 	struct net_device *ndev = can->can.dev;
1262 	struct sk_buff *skb;
1263 	struct can_frame *cf = NULL;
1264 	struct skb_shared_hwtstamps *shhwtstamps;
1265 	struct net_device_stats *stats = &ndev->stats;
1266 
1267 	old_state = can->can.state;
1268 
1269 	bec.txerr = p->header[0] & 0xff;
1270 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1271 
1272 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1273 				      &rx_state);
1274 
1275 	skb = alloc_can_err_skb(ndev, &cf);
1276 
1277 	if (new_state != old_state) {
1278 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1279 					   rx_state);
1280 
1281 		if (old_state == CAN_STATE_BUS_OFF &&
1282 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1283 		    can->can.restart_ms) {
1284 			can->can.can_stats.restarts++;
1285 			if (skb)
1286 				cf->can_id |= CAN_ERR_RESTARTED;
1287 		}
1288 	}
1289 
1290 	can->err_rep_cnt++;
1291 	can->can.can_stats.bus_error++;
1292 	if (p->header[1] & KVASER_PCIEFD_EPACK_DIR_TX)
1293 		stats->tx_errors++;
1294 	else
1295 		stats->rx_errors++;
1296 
1297 	can->bec.txerr = bec.txerr;
1298 	can->bec.rxerr = bec.rxerr;
1299 
1300 	if (!skb) {
1301 		stats->rx_dropped++;
1302 		return -ENOMEM;
1303 	}
1304 
1305 	shhwtstamps = skb_hwtstamps(skb);
1306 	shhwtstamps->hwtstamp =
1307 		ns_to_ktime(div_u64(p->timestamp * 1000,
1308 				    can->kv_pcie->freq_to_ticks_div));
1309 	cf->can_id |= CAN_ERR_BUSERROR;
1310 
1311 	cf->data[6] = bec.txerr;
1312 	cf->data[7] = bec.rxerr;
1313 
1314 	netif_rx(skb);
1315 	return 0;
1316 }
1317 
1318 static int kvaser_pciefd_handle_error_packet(struct kvaser_pciefd *pcie,
1319 					     struct kvaser_pciefd_rx_packet *p)
1320 {
1321 	struct kvaser_pciefd_can *can;
1322 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1323 
1324 	if (ch_id >= pcie->nr_channels)
1325 		return -EIO;
1326 
1327 	can = pcie->can[ch_id];
1328 
1329 	kvaser_pciefd_rx_error_frame(can, p);
1330 	if (can->err_rep_cnt >= KVASER_PCIEFD_MAX_ERR_REP)
1331 		/* Do not report more errors, until bec_poll_timer expires */
1332 		kvaser_pciefd_disable_err_gen(can);
1333 	/* Start polling the error counters */
1334 	mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1335 	return 0;
1336 }
1337 
1338 static int kvaser_pciefd_handle_status_resp(struct kvaser_pciefd_can *can,
1339 					    struct kvaser_pciefd_rx_packet *p)
1340 {
1341 	struct can_berr_counter bec;
1342 	enum can_state old_state, new_state, tx_state, rx_state;
1343 
1344 	old_state = can->can.state;
1345 
1346 	bec.txerr = p->header[0] & 0xff;
1347 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1348 
1349 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1350 				      &rx_state);
1351 
1352 	if (new_state != old_state) {
1353 		struct net_device *ndev = can->can.dev;
1354 		struct sk_buff *skb;
1355 		struct can_frame *cf;
1356 		struct skb_shared_hwtstamps *shhwtstamps;
1357 
1358 		skb = alloc_can_err_skb(ndev, &cf);
1359 		if (!skb) {
1360 			struct net_device_stats *stats = &ndev->stats;
1361 
1362 			stats->rx_dropped++;
1363 			return -ENOMEM;
1364 		}
1365 
1366 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1367 					   rx_state);
1368 
1369 		if (old_state == CAN_STATE_BUS_OFF &&
1370 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1371 		    can->can.restart_ms) {
1372 			can->can.can_stats.restarts++;
1373 			cf->can_id |= CAN_ERR_RESTARTED;
1374 		}
1375 
1376 		shhwtstamps = skb_hwtstamps(skb);
1377 		shhwtstamps->hwtstamp =
1378 			ns_to_ktime(div_u64(p->timestamp * 1000,
1379 					    can->kv_pcie->freq_to_ticks_div));
1380 
1381 		cf->data[6] = bec.txerr;
1382 		cf->data[7] = bec.rxerr;
1383 
1384 		netif_rx(skb);
1385 	}
1386 	can->bec.txerr = bec.txerr;
1387 	can->bec.rxerr = bec.rxerr;
1388 	/* Check if we need to poll the error counters */
1389 	if (bec.txerr || bec.rxerr)
1390 		mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1391 
1392 	return 0;
1393 }
1394 
1395 static int kvaser_pciefd_handle_status_packet(struct kvaser_pciefd *pcie,
1396 					      struct kvaser_pciefd_rx_packet *p)
1397 {
1398 	struct kvaser_pciefd_can *can;
1399 	u8 cmdseq;
1400 	u32 status;
1401 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1402 
1403 	if (ch_id >= pcie->nr_channels)
1404 		return -EIO;
1405 
1406 	can = pcie->can[ch_id];
1407 
1408 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1409 	cmdseq = (status >> KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT) & 0xff;
1410 
1411 	/* Reset done, start abort and flush */
1412 	if (p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1413 	    p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1414 	    p->header[1] & KVASER_PCIEFD_SPACK_AUTO &&
1415 	    cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1416 	    status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1417 		u32 cmd;
1418 
1419 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1420 			  can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1421 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
1422 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
1423 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
1424 
1425 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_TFD,
1426 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1427 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET &&
1428 		   p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1429 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1430 		   status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1431 		/* Reset detected, send end of flush if no packet are in FIFO */
1432 		u8 count = ioread32(can->reg_base +
1433 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1434 
1435 		if (!count)
1436 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1437 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1438 	} else if (!(p->header[1] & KVASER_PCIEFD_SPACK_AUTO) &&
1439 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK)) {
1440 		/* Response to status request received */
1441 		kvaser_pciefd_handle_status_resp(can, p);
1442 		if (can->can.state != CAN_STATE_BUS_OFF &&
1443 		    can->can.state != CAN_STATE_ERROR_ACTIVE) {
1444 			mod_timer(&can->bec_poll_timer,
1445 				  KVASER_PCIEFD_BEC_POLL_FREQ);
1446 		}
1447 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1448 		   !(status & KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK)) {
1449 		/* Reset to bus on detected */
1450 		if (!completion_done(&can->start_comp))
1451 			complete(&can->start_comp);
1452 	}
1453 
1454 	return 0;
1455 }
1456 
1457 static int kvaser_pciefd_handle_eack_packet(struct kvaser_pciefd *pcie,
1458 					    struct kvaser_pciefd_rx_packet *p)
1459 {
1460 	struct kvaser_pciefd_can *can;
1461 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1462 
1463 	if (ch_id >= pcie->nr_channels)
1464 		return -EIO;
1465 
1466 	can = pcie->can[ch_id];
1467 
1468 	/* If this is the last flushed packet, send end of flush */
1469 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1470 		u8 count = ioread32(can->reg_base +
1471 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1472 
1473 		if (count == 0)
1474 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1475 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1476 	} else {
1477 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1478 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1479 		struct net_device_stats *stats = &can->can.dev->stats;
1480 
1481 		stats->tx_bytes += dlc;
1482 		stats->tx_packets++;
1483 
1484 		if (netif_queue_stopped(can->can.dev))
1485 			netif_wake_queue(can->can.dev);
1486 	}
1487 
1488 	return 0;
1489 }
1490 
1491 static void kvaser_pciefd_handle_nack_packet(struct kvaser_pciefd_can *can,
1492 					     struct kvaser_pciefd_rx_packet *p)
1493 {
1494 	struct sk_buff *skb;
1495 	struct net_device_stats *stats = &can->can.dev->stats;
1496 	struct can_frame *cf;
1497 
1498 	skb = alloc_can_err_skb(can->can.dev, &cf);
1499 
1500 	stats->tx_errors++;
1501 	if (p->header[0] & KVASER_PCIEFD_APACKET_ABL) {
1502 		if (skb)
1503 			cf->can_id |= CAN_ERR_LOSTARB;
1504 		can->can.can_stats.arbitration_lost++;
1505 	} else if (skb) {
1506 		cf->can_id |= CAN_ERR_ACK;
1507 	}
1508 
1509 	if (skb) {
1510 		cf->can_id |= CAN_ERR_BUSERROR;
1511 		netif_rx(skb);
1512 	} else {
1513 		stats->rx_dropped++;
1514 		netdev_warn(can->can.dev, "No memory left for err_skb\n");
1515 	}
1516 }
1517 
1518 static int kvaser_pciefd_handle_ack_packet(struct kvaser_pciefd *pcie,
1519 					   struct kvaser_pciefd_rx_packet *p)
1520 {
1521 	struct kvaser_pciefd_can *can;
1522 	bool one_shot_fail = false;
1523 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1524 
1525 	if (ch_id >= pcie->nr_channels)
1526 		return -EIO;
1527 
1528 	can = pcie->can[ch_id];
1529 	/* Ignore control packet ACK */
1530 	if (p->header[0] & KVASER_PCIEFD_APACKET_CT)
1531 		return 0;
1532 
1533 	if (p->header[0] & KVASER_PCIEFD_APACKET_NACK) {
1534 		kvaser_pciefd_handle_nack_packet(can, p);
1535 		one_shot_fail = true;
1536 	}
1537 
1538 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1539 		netdev_dbg(can->can.dev, "Packet was flushed\n");
1540 	} else {
1541 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1542 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1543 		u8 count = ioread32(can->reg_base +
1544 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1545 
1546 		if (count < KVASER_PCIEFD_CAN_TX_MAX_COUNT &&
1547 		    netif_queue_stopped(can->can.dev))
1548 			netif_wake_queue(can->can.dev);
1549 
1550 		if (!one_shot_fail) {
1551 			struct net_device_stats *stats = &can->can.dev->stats;
1552 
1553 			stats->tx_bytes += dlc;
1554 			stats->tx_packets++;
1555 		}
1556 	}
1557 
1558 	return 0;
1559 }
1560 
1561 static int kvaser_pciefd_handle_eflush_packet(struct kvaser_pciefd *pcie,
1562 					      struct kvaser_pciefd_rx_packet *p)
1563 {
1564 	struct kvaser_pciefd_can *can;
1565 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1566 
1567 	if (ch_id >= pcie->nr_channels)
1568 		return -EIO;
1569 
1570 	can = pcie->can[ch_id];
1571 
1572 	if (!completion_done(&can->flush_comp))
1573 		complete(&can->flush_comp);
1574 
1575 	return 0;
1576 }
1577 
1578 static int kvaser_pciefd_read_packet(struct kvaser_pciefd *pcie, int *start_pos,
1579 				     int dma_buf)
1580 {
1581 	__le32 *buffer = pcie->dma_data[dma_buf];
1582 	__le64 timestamp;
1583 	struct kvaser_pciefd_rx_packet packet;
1584 	struct kvaser_pciefd_rx_packet *p = &packet;
1585 	u8 type;
1586 	int pos = *start_pos;
1587 	int size;
1588 	int ret = 0;
1589 
1590 	size = le32_to_cpu(buffer[pos++]);
1591 	if (!size) {
1592 		*start_pos = 0;
1593 		return 0;
1594 	}
1595 
1596 	p->header[0] = le32_to_cpu(buffer[pos++]);
1597 	p->header[1] = le32_to_cpu(buffer[pos++]);
1598 
1599 	/* Read 64-bit timestamp */
1600 	memcpy(&timestamp, &buffer[pos], sizeof(__le64));
1601 	pos += 2;
1602 	p->timestamp = le64_to_cpu(timestamp);
1603 
1604 	type = (p->header[1] >> KVASER_PCIEFD_PACKET_TYPE_SHIFT) & 0xf;
1605 	switch (type) {
1606 	case KVASER_PCIEFD_PACK_TYPE_DATA:
1607 		ret = kvaser_pciefd_handle_data_packet(pcie, p, &buffer[pos]);
1608 		if (!(p->header[0] & KVASER_PCIEFD_RPACKET_RTR)) {
1609 			u8 data_len;
1610 
1611 			data_len = can_fd_dlc2len(p->header[1] >>
1612 					       KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1613 			pos += DIV_ROUND_UP(data_len, 4);
1614 		}
1615 		break;
1616 
1617 	case KVASER_PCIEFD_PACK_TYPE_ACK:
1618 		ret = kvaser_pciefd_handle_ack_packet(pcie, p);
1619 		break;
1620 
1621 	case KVASER_PCIEFD_PACK_TYPE_STATUS:
1622 		ret = kvaser_pciefd_handle_status_packet(pcie, p);
1623 		break;
1624 
1625 	case KVASER_PCIEFD_PACK_TYPE_ERROR:
1626 		ret = kvaser_pciefd_handle_error_packet(pcie, p);
1627 		break;
1628 
1629 	case KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK:
1630 		ret = kvaser_pciefd_handle_eack_packet(pcie, p);
1631 		break;
1632 
1633 	case KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK:
1634 		ret = kvaser_pciefd_handle_eflush_packet(pcie, p);
1635 		break;
1636 
1637 	case KVASER_PCIEFD_PACK_TYPE_ACK_DATA:
1638 	case KVASER_PCIEFD_PACK_TYPE_BUS_LOAD:
1639 	case KVASER_PCIEFD_PACK_TYPE_TXRQ:
1640 		dev_info(&pcie->pci->dev,
1641 			 "Received unexpected packet type 0x%08X\n", type);
1642 		break;
1643 
1644 	default:
1645 		dev_err(&pcie->pci->dev, "Unknown packet type 0x%08X\n", type);
1646 		ret = -EIO;
1647 		break;
1648 	}
1649 
1650 	if (ret)
1651 		return ret;
1652 
1653 	/* Position does not point to the end of the package,
1654 	 * corrupted packet size?
1655 	 */
1656 	if ((*start_pos + size) != pos)
1657 		return -EIO;
1658 
1659 	/* Point to the next packet header, if any */
1660 	*start_pos = pos;
1661 
1662 	return ret;
1663 }
1664 
1665 static int kvaser_pciefd_read_buffer(struct kvaser_pciefd *pcie, int dma_buf)
1666 {
1667 	int pos = 0;
1668 	int res = 0;
1669 
1670 	do {
1671 		res = kvaser_pciefd_read_packet(pcie, &pos, dma_buf);
1672 	} while (!res && pos > 0 && pos < KVASER_PCIEFD_DMA_SIZE);
1673 
1674 	return res;
1675 }
1676 
1677 static int kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
1678 {
1679 	u32 irq;
1680 
1681 	irq = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1682 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
1683 		kvaser_pciefd_read_buffer(pcie, 0);
1684 		/* Reset DMA buffer 0 */
1685 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1686 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1687 	}
1688 
1689 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
1690 		kvaser_pciefd_read_buffer(pcie, 1);
1691 		/* Reset DMA buffer 1 */
1692 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1693 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1694 	}
1695 
1696 	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
1697 	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
1698 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
1699 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
1700 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
1701 
1702 	iowrite32(irq, pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1703 	return 0;
1704 }
1705 
1706 static int kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
1707 {
1708 	u32 irq = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1709 
1710 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF)
1711 		netdev_err(can->can.dev, "Tx FIFO overflow\n");
1712 
1713 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TFD) {
1714 		u8 count = ioread32(can->reg_base +
1715 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1716 
1717 		if (count == 0)
1718 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1719 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1720 	}
1721 
1722 	if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP)
1723 		netdev_err(can->can.dev,
1724 			   "Fail to change bittiming, when not in reset mode\n");
1725 
1726 	if (irq & KVASER_PCIEFD_KCAN_IRQ_FDIC)
1727 		netdev_err(can->can.dev, "CAN FD frame in CAN mode\n");
1728 
1729 	if (irq & KVASER_PCIEFD_KCAN_IRQ_ROF)
1730 		netdev_err(can->can.dev, "Rx FIFO overflow\n");
1731 
1732 	iowrite32(irq, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1733 	return 0;
1734 }
1735 
1736 static irqreturn_t kvaser_pciefd_irq_handler(int irq, void *dev)
1737 {
1738 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
1739 	u32 board_irq;
1740 	int i;
1741 
1742 	board_irq = ioread32(pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1743 
1744 	if (!(board_irq & KVASER_PCIEFD_IRQ_ALL_MSK))
1745 		return IRQ_NONE;
1746 
1747 	if (board_irq & KVASER_PCIEFD_IRQ_SRB)
1748 		kvaser_pciefd_receive_irq(pcie);
1749 
1750 	for (i = 0; i < pcie->nr_channels; i++) {
1751 		if (!pcie->can[i]) {
1752 			dev_err(&pcie->pci->dev,
1753 				"IRQ mask points to unallocated controller\n");
1754 			break;
1755 		}
1756 
1757 		/* Check that mask matches channel (i) IRQ mask */
1758 		if (board_irq & (1 << i))
1759 			kvaser_pciefd_transmit_irq(pcie->can[i]);
1760 	}
1761 
1762 	iowrite32(board_irq, pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1763 	return IRQ_HANDLED;
1764 }
1765 
1766 static void kvaser_pciefd_teardown_can_ctrls(struct kvaser_pciefd *pcie)
1767 {
1768 	int i;
1769 	struct kvaser_pciefd_can *can;
1770 
1771 	for (i = 0; i < pcie->nr_channels; i++) {
1772 		can = pcie->can[i];
1773 		if (can) {
1774 			iowrite32(0,
1775 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1776 			kvaser_pciefd_pwm_stop(can);
1777 			free_candev(can->can.dev);
1778 		}
1779 	}
1780 }
1781 
1782 static int kvaser_pciefd_probe(struct pci_dev *pdev,
1783 			       const struct pci_device_id *id)
1784 {
1785 	int err;
1786 	struct kvaser_pciefd *pcie;
1787 
1788 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
1789 	if (!pcie)
1790 		return -ENOMEM;
1791 
1792 	pci_set_drvdata(pdev, pcie);
1793 	pcie->pci = pdev;
1794 
1795 	err = pci_enable_device(pdev);
1796 	if (err)
1797 		return err;
1798 
1799 	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
1800 	if (err)
1801 		goto err_disable_pci;
1802 
1803 	pcie->reg_base = pci_iomap(pdev, 0, 0);
1804 	if (!pcie->reg_base) {
1805 		err = -ENOMEM;
1806 		goto err_release_regions;
1807 	}
1808 
1809 	err = kvaser_pciefd_setup_board(pcie);
1810 	if (err)
1811 		goto err_pci_iounmap;
1812 
1813 	err = kvaser_pciefd_setup_dma(pcie);
1814 	if (err)
1815 		goto err_pci_iounmap;
1816 
1817 	pci_set_master(pdev);
1818 
1819 	err = kvaser_pciefd_setup_can_ctrls(pcie);
1820 	if (err)
1821 		goto err_teardown_can_ctrls;
1822 
1823 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
1824 		  pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1825 
1826 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1 |
1827 		  KVASER_PCIEFD_SRB_IRQ_DOF0 | KVASER_PCIEFD_SRB_IRQ_DOF1 |
1828 		  KVASER_PCIEFD_SRB_IRQ_DUF0 | KVASER_PCIEFD_SRB_IRQ_DUF1,
1829 		  pcie->reg_base + KVASER_PCIEFD_SRB_IEN_REG);
1830 
1831 	/* Reset IRQ handling, expected to be off before */
1832 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1833 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1834 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1835 		  pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1836 
1837 	/* Ready the DMA buffers */
1838 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1839 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1840 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1841 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1842 
1843 	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
1844 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
1845 	if (err)
1846 		goto err_teardown_can_ctrls;
1847 
1848 	err = kvaser_pciefd_reg_candev(pcie);
1849 	if (err)
1850 		goto err_free_irq;
1851 
1852 	return 0;
1853 
1854 err_free_irq:
1855 	free_irq(pcie->pci->irq, pcie);
1856 
1857 err_teardown_can_ctrls:
1858 	kvaser_pciefd_teardown_can_ctrls(pcie);
1859 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1860 	pci_clear_master(pdev);
1861 
1862 err_pci_iounmap:
1863 	pci_iounmap(pdev, pcie->reg_base);
1864 
1865 err_release_regions:
1866 	pci_release_regions(pdev);
1867 
1868 err_disable_pci:
1869 	pci_disable_device(pdev);
1870 
1871 	return err;
1872 }
1873 
1874 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
1875 {
1876 	struct kvaser_pciefd_can *can;
1877 	int i;
1878 
1879 	for (i = 0; i < pcie->nr_channels; i++) {
1880 		can = pcie->can[i];
1881 		if (can) {
1882 			iowrite32(0,
1883 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1884 			unregister_candev(can->can.dev);
1885 			del_timer(&can->bec_poll_timer);
1886 			kvaser_pciefd_pwm_stop(can);
1887 			free_candev(can->can.dev);
1888 		}
1889 	}
1890 }
1891 
1892 static void kvaser_pciefd_remove(struct pci_dev *pdev)
1893 {
1894 	struct kvaser_pciefd *pcie = pci_get_drvdata(pdev);
1895 
1896 	kvaser_pciefd_remove_all_ctrls(pcie);
1897 
1898 	/* Turn off IRQ generation */
1899 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1900 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1901 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1902 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1903 
1904 	free_irq(pcie->pci->irq, pcie);
1905 
1906 	pci_clear_master(pdev);
1907 	pci_iounmap(pdev, pcie->reg_base);
1908 	pci_release_regions(pdev);
1909 	pci_disable_device(pdev);
1910 }
1911 
1912 static struct pci_driver kvaser_pciefd = {
1913 	.name = KVASER_PCIEFD_DRV_NAME,
1914 	.id_table = kvaser_pciefd_id_table,
1915 	.probe = kvaser_pciefd_probe,
1916 	.remove = kvaser_pciefd_remove,
1917 };
1918 
1919 module_pci_driver(kvaser_pciefd)
1920