xref: /openbmc/linux/drivers/net/can/kvaser_pciefd.c (revision 54a611b6)
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/ethtool.h>
13 #include <linux/pci.h>
14 #include <linux/can/dev.h>
15 #include <linux/timer.h>
16 #include <linux/netdevice.h>
17 #include <linux/crc32.h>
18 #include <linux/iopoll.h>
19 
20 MODULE_LICENSE("Dual BSD/GPL");
21 MODULE_AUTHOR("Kvaser AB <support@kvaser.com>");
22 MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
23 
24 #define KVASER_PCIEFD_DRV_NAME "kvaser_pciefd"
25 
26 #define KVASER_PCIEFD_WAIT_TIMEOUT msecs_to_jiffies(1000)
27 #define KVASER_PCIEFD_BEC_POLL_FREQ (jiffies + msecs_to_jiffies(200))
28 #define KVASER_PCIEFD_MAX_ERR_REP 256
29 #define KVASER_PCIEFD_CAN_TX_MAX_COUNT 17
30 #define KVASER_PCIEFD_MAX_CAN_CHANNELS 4
31 #define KVASER_PCIEFD_DMA_COUNT 2
32 
33 #define KVASER_PCIEFD_DMA_SIZE (4 * 1024)
34 #define KVASER_PCIEFD_64BIT_DMA_BIT BIT(0)
35 
36 #define KVASER_PCIEFD_VENDOR 0x1a07
37 #define KVASER_PCIEFD_4HS_ID 0x0d
38 #define KVASER_PCIEFD_2HS_ID 0x0e
39 #define KVASER_PCIEFD_HS_ID 0x0f
40 #define KVASER_PCIEFD_MINIPCIE_HS_ID 0x10
41 #define KVASER_PCIEFD_MINIPCIE_2HS_ID 0x11
42 
43 /* PCIe IRQ registers */
44 #define KVASER_PCIEFD_IRQ_REG 0x40
45 #define KVASER_PCIEFD_IEN_REG 0x50
46 /* DMA map */
47 #define KVASER_PCIEFD_DMA_MAP_BASE 0x1000
48 /* Kvaser KCAN CAN controller registers */
49 #define KVASER_PCIEFD_KCAN0_BASE 0x10000
50 #define KVASER_PCIEFD_KCAN_BASE_OFFSET 0x1000
51 #define KVASER_PCIEFD_KCAN_FIFO_REG 0x100
52 #define KVASER_PCIEFD_KCAN_FIFO_LAST_REG 0x180
53 #define KVASER_PCIEFD_KCAN_CTRL_REG 0x2c0
54 #define KVASER_PCIEFD_KCAN_CMD_REG 0x400
55 #define KVASER_PCIEFD_KCAN_IEN_REG 0x408
56 #define KVASER_PCIEFD_KCAN_IRQ_REG 0x410
57 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_REG 0x414
58 #define KVASER_PCIEFD_KCAN_STAT_REG 0x418
59 #define KVASER_PCIEFD_KCAN_MODE_REG 0x41c
60 #define KVASER_PCIEFD_KCAN_BTRN_REG 0x420
61 #define KVASER_PCIEFD_KCAN_BUS_LOAD_REG 0x424
62 #define KVASER_PCIEFD_KCAN_BTRD_REG 0x428
63 #define KVASER_PCIEFD_KCAN_PWM_REG 0x430
64 /* Loopback control register */
65 #define KVASER_PCIEFD_LOOP_REG 0x1f000
66 /* System identification and information registers */
67 #define KVASER_PCIEFD_SYSID_BASE 0x1f020
68 #define KVASER_PCIEFD_SYSID_VERSION_REG (KVASER_PCIEFD_SYSID_BASE + 0x8)
69 #define KVASER_PCIEFD_SYSID_CANFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0xc)
70 #define KVASER_PCIEFD_SYSID_BUSFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0x10)
71 #define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
72 /* Shared receive buffer registers */
73 #define KVASER_PCIEFD_SRB_BASE 0x1f200
74 #define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
75 #define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
76 #define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
77 #define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
78 #define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
79 /* EPCS flash controller registers */
80 #define KVASER_PCIEFD_SPI_BASE 0x1fc00
81 #define KVASER_PCIEFD_SPI_RX_REG KVASER_PCIEFD_SPI_BASE
82 #define KVASER_PCIEFD_SPI_TX_REG (KVASER_PCIEFD_SPI_BASE + 0x4)
83 #define KVASER_PCIEFD_SPI_STATUS_REG (KVASER_PCIEFD_SPI_BASE + 0x8)
84 #define KVASER_PCIEFD_SPI_CTRL_REG (KVASER_PCIEFD_SPI_BASE + 0xc)
85 #define KVASER_PCIEFD_SPI_SSEL_REG (KVASER_PCIEFD_SPI_BASE + 0x14)
86 
87 #define KVASER_PCIEFD_IRQ_ALL_MSK 0x1f
88 #define KVASER_PCIEFD_IRQ_SRB BIT(4)
89 
90 #define KVASER_PCIEFD_SYSID_NRCHAN_SHIFT 24
91 #define KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT 16
92 #define KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT 1
93 
94 /* Reset DMA buffer 0, 1 and FIFO offset */
95 #define KVASER_PCIEFD_SRB_CMD_RDB0 BIT(4)
96 #define KVASER_PCIEFD_SRB_CMD_RDB1 BIT(5)
97 #define KVASER_PCIEFD_SRB_CMD_FOR BIT(0)
98 
99 /* DMA packet done, buffer 0 and 1 */
100 #define KVASER_PCIEFD_SRB_IRQ_DPD0 BIT(8)
101 #define KVASER_PCIEFD_SRB_IRQ_DPD1 BIT(9)
102 /* DMA overflow, buffer 0 and 1 */
103 #define KVASER_PCIEFD_SRB_IRQ_DOF0 BIT(10)
104 #define KVASER_PCIEFD_SRB_IRQ_DOF1 BIT(11)
105 /* DMA underflow, buffer 0 and 1 */
106 #define KVASER_PCIEFD_SRB_IRQ_DUF0 BIT(12)
107 #define KVASER_PCIEFD_SRB_IRQ_DUF1 BIT(13)
108 
109 /* DMA idle */
110 #define KVASER_PCIEFD_SRB_STAT_DI BIT(15)
111 /* DMA support */
112 #define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
113 
114 /* DMA Enable */
115 #define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
116 
117 /* EPCS flash controller definitions */
118 #define KVASER_PCIEFD_CFG_IMG_SZ (64 * 1024)
119 #define KVASER_PCIEFD_CFG_IMG_OFFSET (31 * 65536L)
120 #define KVASER_PCIEFD_CFG_MAX_PARAMS 256
121 #define KVASER_PCIEFD_CFG_MAGIC 0xcafef00d
122 #define KVASER_PCIEFD_CFG_PARAM_MAX_SZ 24
123 #define KVASER_PCIEFD_CFG_SYS_VER 1
124 #define KVASER_PCIEFD_CFG_PARAM_NR_CHAN 130
125 #define KVASER_PCIEFD_SPI_TMT BIT(5)
126 #define KVASER_PCIEFD_SPI_TRDY BIT(6)
127 #define KVASER_PCIEFD_SPI_RRDY BIT(7)
128 #define KVASER_PCIEFD_FLASH_ID_EPCS16 0x14
129 /* Commands for controlling the onboard flash */
130 #define KVASER_PCIEFD_FLASH_RES_CMD 0xab
131 #define KVASER_PCIEFD_FLASH_READ_CMD 0x3
132 #define KVASER_PCIEFD_FLASH_STATUS_CMD 0x5
133 
134 /* Kvaser KCAN definitions */
135 #define KVASER_PCIEFD_KCAN_CTRL_EFLUSH (4 << 29)
136 #define KVASER_PCIEFD_KCAN_CTRL_EFRAME (5 << 29)
137 
138 #define KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT 16
139 /* Request status packet */
140 #define KVASER_PCIEFD_KCAN_CMD_SRQ BIT(0)
141 /* Abort, flush and reset */
142 #define KVASER_PCIEFD_KCAN_CMD_AT BIT(1)
143 
144 /* Tx FIFO unaligned read */
145 #define KVASER_PCIEFD_KCAN_IRQ_TAR BIT(0)
146 /* Tx FIFO unaligned end */
147 #define KVASER_PCIEFD_KCAN_IRQ_TAE BIT(1)
148 /* Bus parameter protection error */
149 #define KVASER_PCIEFD_KCAN_IRQ_BPP BIT(2)
150 /* FDF bit when controller is in classic mode */
151 #define KVASER_PCIEFD_KCAN_IRQ_FDIC BIT(3)
152 /* Rx FIFO overflow */
153 #define KVASER_PCIEFD_KCAN_IRQ_ROF BIT(5)
154 /* Abort done */
155 #define KVASER_PCIEFD_KCAN_IRQ_ABD BIT(13)
156 /* Tx buffer flush done */
157 #define KVASER_PCIEFD_KCAN_IRQ_TFD BIT(14)
158 /* Tx FIFO overflow */
159 #define KVASER_PCIEFD_KCAN_IRQ_TOF BIT(15)
160 /* Tx FIFO empty */
161 #define KVASER_PCIEFD_KCAN_IRQ_TE BIT(16)
162 /* Transmitter unaligned */
163 #define KVASER_PCIEFD_KCAN_IRQ_TAL BIT(17)
164 
165 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT 16
166 
167 #define KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT 24
168 /* Abort request */
169 #define KVASER_PCIEFD_KCAN_STAT_AR BIT(7)
170 /* Idle state. Controller in reset mode and no abort or flush pending */
171 #define KVASER_PCIEFD_KCAN_STAT_IDLE BIT(10)
172 /* Bus off */
173 #define KVASER_PCIEFD_KCAN_STAT_BOFF BIT(11)
174 /* Reset mode request */
175 #define KVASER_PCIEFD_KCAN_STAT_RMR BIT(14)
176 /* Controller in reset mode */
177 #define KVASER_PCIEFD_KCAN_STAT_IRM BIT(15)
178 /* Controller got one-shot capability */
179 #define KVASER_PCIEFD_KCAN_STAT_CAP BIT(16)
180 /* Controller got CAN FD capability */
181 #define KVASER_PCIEFD_KCAN_STAT_FD BIT(19)
182 #define KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK (KVASER_PCIEFD_KCAN_STAT_AR | \
183 	KVASER_PCIEFD_KCAN_STAT_BOFF | KVASER_PCIEFD_KCAN_STAT_RMR | \
184 	KVASER_PCIEFD_KCAN_STAT_IRM)
185 
186 /* Reset mode */
187 #define KVASER_PCIEFD_KCAN_MODE_RM BIT(8)
188 /* Listen only mode */
189 #define KVASER_PCIEFD_KCAN_MODE_LOM BIT(9)
190 /* Error packet enable */
191 #define KVASER_PCIEFD_KCAN_MODE_EPEN BIT(12)
192 /* CAN FD non-ISO */
193 #define KVASER_PCIEFD_KCAN_MODE_NIFDEN BIT(15)
194 /* Acknowledgment packet type */
195 #define KVASER_PCIEFD_KCAN_MODE_APT BIT(20)
196 /* Active error flag enable. Clear to force error passive */
197 #define KVASER_PCIEFD_KCAN_MODE_EEN BIT(23)
198 /* Classic CAN mode */
199 #define KVASER_PCIEFD_KCAN_MODE_CCM BIT(31)
200 
201 #define KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT 13
202 #define KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT 17
203 #define KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT 26
204 
205 #define KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT 16
206 
207 /* Kvaser KCAN packet types */
208 #define KVASER_PCIEFD_PACK_TYPE_DATA 0
209 #define KVASER_PCIEFD_PACK_TYPE_ACK 1
210 #define KVASER_PCIEFD_PACK_TYPE_TXRQ 2
211 #define KVASER_PCIEFD_PACK_TYPE_ERROR 3
212 #define KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK 4
213 #define KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK 5
214 #define KVASER_PCIEFD_PACK_TYPE_ACK_DATA 6
215 #define KVASER_PCIEFD_PACK_TYPE_STATUS 8
216 #define KVASER_PCIEFD_PACK_TYPE_BUS_LOAD 9
217 
218 /* Kvaser KCAN packet common definitions */
219 #define KVASER_PCIEFD_PACKET_SEQ_MSK 0xff
220 #define KVASER_PCIEFD_PACKET_CHID_SHIFT 25
221 #define KVASER_PCIEFD_PACKET_TYPE_SHIFT 28
222 
223 /* Kvaser KCAN TDATA and RDATA first word */
224 #define KVASER_PCIEFD_RPACKET_IDE BIT(30)
225 #define KVASER_PCIEFD_RPACKET_RTR BIT(29)
226 /* Kvaser KCAN TDATA and RDATA second word */
227 #define KVASER_PCIEFD_RPACKET_ESI BIT(13)
228 #define KVASER_PCIEFD_RPACKET_BRS BIT(14)
229 #define KVASER_PCIEFD_RPACKET_FDF BIT(15)
230 #define KVASER_PCIEFD_RPACKET_DLC_SHIFT 8
231 /* Kvaser KCAN TDATA second word */
232 #define KVASER_PCIEFD_TPACKET_SMS BIT(16)
233 #define KVASER_PCIEFD_TPACKET_AREQ BIT(31)
234 
235 /* Kvaser KCAN APACKET */
236 #define KVASER_PCIEFD_APACKET_FLU BIT(8)
237 #define KVASER_PCIEFD_APACKET_CT BIT(9)
238 #define KVASER_PCIEFD_APACKET_ABL BIT(10)
239 #define KVASER_PCIEFD_APACKET_NACK BIT(11)
240 
241 /* Kvaser KCAN SPACK first word */
242 #define KVASER_PCIEFD_SPACK_RXERR_SHIFT 8
243 #define KVASER_PCIEFD_SPACK_BOFF BIT(16)
244 #define KVASER_PCIEFD_SPACK_IDET BIT(20)
245 #define KVASER_PCIEFD_SPACK_IRM BIT(21)
246 #define KVASER_PCIEFD_SPACK_RMCD BIT(22)
247 /* Kvaser KCAN SPACK second word */
248 #define KVASER_PCIEFD_SPACK_AUTO BIT(21)
249 #define KVASER_PCIEFD_SPACK_EWLR BIT(23)
250 #define KVASER_PCIEFD_SPACK_EPLR BIT(24)
251 
252 /* Kvaser KCAN_EPACK second word */
253 #define KVASER_PCIEFD_EPACK_DIR_TX BIT(0)
254 
255 struct kvaser_pciefd;
256 
257 struct kvaser_pciefd_can {
258 	struct can_priv can;
259 	struct kvaser_pciefd *kv_pcie;
260 	void __iomem *reg_base;
261 	struct can_berr_counter bec;
262 	u8 cmd_seq;
263 	int err_rep_cnt;
264 	int echo_idx;
265 	spinlock_t lock; /* Locks sensitive registers (e.g. MODE) */
266 	spinlock_t echo_lock; /* Locks the message echo buffer */
267 	struct timer_list bec_poll_timer;
268 	struct completion start_comp, flush_comp;
269 };
270 
271 struct kvaser_pciefd {
272 	struct pci_dev *pci;
273 	void __iomem *reg_base;
274 	struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
275 	void *dma_data[KVASER_PCIEFD_DMA_COUNT];
276 	u8 nr_channels;
277 	u32 bus_freq;
278 	u32 freq;
279 	u32 freq_to_ticks_div;
280 };
281 
282 struct kvaser_pciefd_rx_packet {
283 	u32 header[2];
284 	u64 timestamp;
285 };
286 
287 struct kvaser_pciefd_tx_packet {
288 	u32 header[2];
289 	u8 data[64];
290 };
291 
292 static const struct can_bittiming_const kvaser_pciefd_bittiming_const = {
293 	.name = KVASER_PCIEFD_DRV_NAME,
294 	.tseg1_min = 1,
295 	.tseg1_max = 512,
296 	.tseg2_min = 1,
297 	.tseg2_max = 32,
298 	.sjw_max = 16,
299 	.brp_min = 1,
300 	.brp_max = 8192,
301 	.brp_inc = 1,
302 };
303 
304 struct kvaser_pciefd_cfg_param {
305 	__le32 magic;
306 	__le32 nr;
307 	__le32 len;
308 	u8 data[KVASER_PCIEFD_CFG_PARAM_MAX_SZ];
309 };
310 
311 struct kvaser_pciefd_cfg_img {
312 	__le32 version;
313 	__le32 magic;
314 	__le32 crc;
315 	struct kvaser_pciefd_cfg_param params[KVASER_PCIEFD_CFG_MAX_PARAMS];
316 };
317 
318 static struct pci_device_id kvaser_pciefd_id_table[] = {
319 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_4HS_ID), },
320 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_2HS_ID), },
321 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_HS_ID), },
322 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_HS_ID), },
323 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_2HS_ID), },
324 	{ 0,},
325 };
326 MODULE_DEVICE_TABLE(pci, kvaser_pciefd_id_table);
327 
328 /* Onboard flash memory functions */
329 static int kvaser_pciefd_spi_wait_loop(struct kvaser_pciefd *pcie, int msk)
330 {
331 	u32 res;
332 	int ret;
333 
334 	ret = readl_poll_timeout(pcie->reg_base + KVASER_PCIEFD_SPI_STATUS_REG,
335 				 res, res & msk, 0, 10);
336 
337 	return ret;
338 }
339 
340 static int kvaser_pciefd_spi_cmd(struct kvaser_pciefd *pcie, const u8 *tx,
341 				 u32 tx_len, u8 *rx, u32 rx_len)
342 {
343 	int c;
344 
345 	iowrite32(BIT(0), pcie->reg_base + KVASER_PCIEFD_SPI_SSEL_REG);
346 	iowrite32(BIT(10), pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
347 	ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
348 
349 	c = tx_len;
350 	while (c--) {
351 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
352 			return -EIO;
353 
354 		iowrite32(*tx++, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
355 
356 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
357 			return -EIO;
358 
359 		ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
360 	}
361 
362 	c = rx_len;
363 	while (c-- > 0) {
364 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
365 			return -EIO;
366 
367 		iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
368 
369 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
370 			return -EIO;
371 
372 		*rx++ = ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
373 	}
374 
375 	if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TMT))
376 		return -EIO;
377 
378 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
379 
380 	if (c != -1) {
381 		dev_err(&pcie->pci->dev, "Flash SPI transfer failed\n");
382 		return -EIO;
383 	}
384 
385 	return 0;
386 }
387 
388 static int kvaser_pciefd_cfg_read_and_verify(struct kvaser_pciefd *pcie,
389 					     struct kvaser_pciefd_cfg_img *img)
390 {
391 	int offset = KVASER_PCIEFD_CFG_IMG_OFFSET;
392 	int res, crc;
393 	u8 *crc_buff;
394 
395 	u8 cmd[] = {
396 		KVASER_PCIEFD_FLASH_READ_CMD,
397 		(u8)((offset >> 16) & 0xff),
398 		(u8)((offset >> 8) & 0xff),
399 		(u8)(offset & 0xff)
400 	};
401 
402 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), (u8 *)img,
403 				    KVASER_PCIEFD_CFG_IMG_SZ);
404 	if (res)
405 		return res;
406 
407 	crc_buff = (u8 *)img->params;
408 
409 	if (le32_to_cpu(img->version) != KVASER_PCIEFD_CFG_SYS_VER) {
410 		dev_err(&pcie->pci->dev,
411 			"Config flash corrupted, version number is wrong\n");
412 		return -ENODEV;
413 	}
414 
415 	if (le32_to_cpu(img->magic) != KVASER_PCIEFD_CFG_MAGIC) {
416 		dev_err(&pcie->pci->dev,
417 			"Config flash corrupted, magic number is wrong\n");
418 		return -ENODEV;
419 	}
420 
421 	crc = ~crc32_be(0xffffffff, crc_buff, sizeof(img->params));
422 	if (le32_to_cpu(img->crc) != crc) {
423 		dev_err(&pcie->pci->dev,
424 			"Stored CRC does not match flash image contents\n");
425 		return -EIO;
426 	}
427 
428 	return 0;
429 }
430 
431 static void kvaser_pciefd_cfg_read_params(struct kvaser_pciefd *pcie,
432 					  struct kvaser_pciefd_cfg_img *img)
433 {
434 	struct kvaser_pciefd_cfg_param *param;
435 
436 	param = &img->params[KVASER_PCIEFD_CFG_PARAM_NR_CHAN];
437 	memcpy(&pcie->nr_channels, param->data, le32_to_cpu(param->len));
438 }
439 
440 static int kvaser_pciefd_read_cfg(struct kvaser_pciefd *pcie)
441 {
442 	int res;
443 	struct kvaser_pciefd_cfg_img *img;
444 
445 	/* Read electronic signature */
446 	u8 cmd[] = {KVASER_PCIEFD_FLASH_RES_CMD, 0, 0, 0};
447 
448 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), cmd, 1);
449 	if (res)
450 		return -EIO;
451 
452 	img = kmalloc(KVASER_PCIEFD_CFG_IMG_SZ, GFP_KERNEL);
453 	if (!img)
454 		return -ENOMEM;
455 
456 	if (cmd[0] != KVASER_PCIEFD_FLASH_ID_EPCS16) {
457 		dev_err(&pcie->pci->dev,
458 			"Flash id is 0x%x instead of expected EPCS16 (0x%x)\n",
459 			cmd[0], KVASER_PCIEFD_FLASH_ID_EPCS16);
460 
461 		res = -ENODEV;
462 		goto image_free;
463 	}
464 
465 	cmd[0] = KVASER_PCIEFD_FLASH_STATUS_CMD;
466 	res = kvaser_pciefd_spi_cmd(pcie, cmd, 1, cmd, 1);
467 	if (res) {
468 		goto image_free;
469 	} else if (cmd[0] & 1) {
470 		res = -EIO;
471 		/* No write is ever done, the WIP should never be set */
472 		dev_err(&pcie->pci->dev, "Unexpected WIP bit set in flash\n");
473 		goto image_free;
474 	}
475 
476 	res = kvaser_pciefd_cfg_read_and_verify(pcie, img);
477 	if (res) {
478 		res = -EIO;
479 		goto image_free;
480 	}
481 
482 	kvaser_pciefd_cfg_read_params(pcie, img);
483 
484 image_free:
485 	kfree(img);
486 	return res;
487 }
488 
489 static void kvaser_pciefd_request_status(struct kvaser_pciefd_can *can)
490 {
491 	u32 cmd;
492 
493 	cmd = KVASER_PCIEFD_KCAN_CMD_SRQ;
494 	cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
495 	iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
496 }
497 
498 static void kvaser_pciefd_enable_err_gen(struct kvaser_pciefd_can *can)
499 {
500 	u32 mode;
501 	unsigned long irq;
502 
503 	spin_lock_irqsave(&can->lock, irq);
504 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
505 	if (!(mode & KVASER_PCIEFD_KCAN_MODE_EPEN)) {
506 		mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
507 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
508 	}
509 	spin_unlock_irqrestore(&can->lock, irq);
510 }
511 
512 static void kvaser_pciefd_disable_err_gen(struct kvaser_pciefd_can *can)
513 {
514 	u32 mode;
515 	unsigned long irq;
516 
517 	spin_lock_irqsave(&can->lock, irq);
518 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
519 	mode &= ~KVASER_PCIEFD_KCAN_MODE_EPEN;
520 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
521 	spin_unlock_irqrestore(&can->lock, irq);
522 }
523 
524 static int kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
525 {
526 	u32 msk;
527 
528 	msk = KVASER_PCIEFD_KCAN_IRQ_TE | KVASER_PCIEFD_KCAN_IRQ_ROF |
529 	      KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD |
530 	      KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL |
531 	      KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP |
532 	      KVASER_PCIEFD_KCAN_IRQ_TAR | KVASER_PCIEFD_KCAN_IRQ_TFD;
533 
534 	iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
535 
536 	return 0;
537 }
538 
539 static void kvaser_pciefd_setup_controller(struct kvaser_pciefd_can *can)
540 {
541 	u32 mode;
542 	unsigned long irq;
543 
544 	spin_lock_irqsave(&can->lock, irq);
545 
546 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
547 	if (can->can.ctrlmode & CAN_CTRLMODE_FD) {
548 		mode &= ~KVASER_PCIEFD_KCAN_MODE_CCM;
549 		if (can->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
550 			mode |= KVASER_PCIEFD_KCAN_MODE_NIFDEN;
551 		else
552 			mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
553 	} else {
554 		mode |= KVASER_PCIEFD_KCAN_MODE_CCM;
555 		mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
556 	}
557 
558 	if (can->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
559 		mode |= KVASER_PCIEFD_KCAN_MODE_LOM;
560 
561 	mode |= KVASER_PCIEFD_KCAN_MODE_EEN;
562 	mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
563 	/* Use ACK packet type */
564 	mode &= ~KVASER_PCIEFD_KCAN_MODE_APT;
565 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
566 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
567 
568 	spin_unlock_irqrestore(&can->lock, irq);
569 }
570 
571 static void kvaser_pciefd_start_controller_flush(struct kvaser_pciefd_can *can)
572 {
573 	u32 status;
574 	unsigned long irq;
575 
576 	spin_lock_irqsave(&can->lock, irq);
577 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
578 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
579 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
580 
581 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
582 	if (status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
583 		u32 cmd;
584 
585 		/* If controller is already idle, run abort, flush and reset */
586 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
587 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
588 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
589 	} else if (!(status & KVASER_PCIEFD_KCAN_STAT_RMR)) {
590 		u32 mode;
591 
592 		/* Put controller in reset mode */
593 		mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
594 		mode |= KVASER_PCIEFD_KCAN_MODE_RM;
595 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
596 	}
597 
598 	spin_unlock_irqrestore(&can->lock, irq);
599 }
600 
601 static int kvaser_pciefd_bus_on(struct kvaser_pciefd_can *can)
602 {
603 	u32 mode;
604 	unsigned long irq;
605 
606 	del_timer(&can->bec_poll_timer);
607 
608 	if (!completion_done(&can->flush_comp))
609 		kvaser_pciefd_start_controller_flush(can);
610 
611 	if (!wait_for_completion_timeout(&can->flush_comp,
612 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
613 		netdev_err(can->can.dev, "Timeout during bus on flush\n");
614 		return -ETIMEDOUT;
615 	}
616 
617 	spin_lock_irqsave(&can->lock, irq);
618 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
619 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
620 
621 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD,
622 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
623 
624 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
625 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
626 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
627 	spin_unlock_irqrestore(&can->lock, irq);
628 
629 	if (!wait_for_completion_timeout(&can->start_comp,
630 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
631 		netdev_err(can->can.dev, "Timeout during bus on reset\n");
632 		return -ETIMEDOUT;
633 	}
634 	/* Reset interrupt handling */
635 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
636 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
637 
638 	kvaser_pciefd_set_tx_irq(can);
639 	kvaser_pciefd_setup_controller(can);
640 
641 	can->can.state = CAN_STATE_ERROR_ACTIVE;
642 	netif_wake_queue(can->can.dev);
643 	can->bec.txerr = 0;
644 	can->bec.rxerr = 0;
645 	can->err_rep_cnt = 0;
646 
647 	return 0;
648 }
649 
650 static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
651 {
652 	u8 top;
653 	u32 pwm_ctrl;
654 	unsigned long irq;
655 
656 	spin_lock_irqsave(&can->lock, irq);
657 	pwm_ctrl = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
658 	top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;
659 
660 	/* Set duty cycle to zero */
661 	pwm_ctrl |= top;
662 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
663 	spin_unlock_irqrestore(&can->lock, irq);
664 }
665 
666 static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
667 {
668 	int top, trigger;
669 	u32 pwm_ctrl;
670 	unsigned long irq;
671 
672 	kvaser_pciefd_pwm_stop(can);
673 	spin_lock_irqsave(&can->lock, irq);
674 
675 	/* Set frequency to 500 KHz*/
676 	top = can->kv_pcie->bus_freq / (2 * 500000) - 1;
677 
678 	pwm_ctrl = top & 0xff;
679 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
680 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
681 
682 	/* Set duty cycle to 95 */
683 	trigger = (100 * top - 95 * (top + 1) + 50) / 100;
684 	pwm_ctrl = trigger & 0xff;
685 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
686 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
687 	spin_unlock_irqrestore(&can->lock, irq);
688 }
689 
690 static int kvaser_pciefd_open(struct net_device *netdev)
691 {
692 	int err;
693 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
694 
695 	err = open_candev(netdev);
696 	if (err)
697 		return err;
698 
699 	err = kvaser_pciefd_bus_on(can);
700 	if (err) {
701 		close_candev(netdev);
702 		return err;
703 	}
704 
705 	return 0;
706 }
707 
708 static int kvaser_pciefd_stop(struct net_device *netdev)
709 {
710 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
711 	int ret = 0;
712 
713 	/* Don't interrupt ongoing flush */
714 	if (!completion_done(&can->flush_comp))
715 		kvaser_pciefd_start_controller_flush(can);
716 
717 	if (!wait_for_completion_timeout(&can->flush_comp,
718 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
719 		netdev_err(can->can.dev, "Timeout during stop\n");
720 		ret = -ETIMEDOUT;
721 	} else {
722 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
723 		del_timer(&can->bec_poll_timer);
724 	}
725 	close_candev(netdev);
726 
727 	return ret;
728 }
729 
730 static int kvaser_pciefd_prepare_tx_packet(struct kvaser_pciefd_tx_packet *p,
731 					   struct kvaser_pciefd_can *can,
732 					   struct sk_buff *skb)
733 {
734 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
735 	int packet_size;
736 	int seq = can->echo_idx;
737 
738 	memset(p, 0, sizeof(*p));
739 
740 	if (can->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
741 		p->header[1] |= KVASER_PCIEFD_TPACKET_SMS;
742 
743 	if (cf->can_id & CAN_RTR_FLAG)
744 		p->header[0] |= KVASER_PCIEFD_RPACKET_RTR;
745 
746 	if (cf->can_id & CAN_EFF_FLAG)
747 		p->header[0] |= KVASER_PCIEFD_RPACKET_IDE;
748 
749 	p->header[0] |= cf->can_id & CAN_EFF_MASK;
750 	p->header[1] |= can_fd_len2dlc(cf->len) << KVASER_PCIEFD_RPACKET_DLC_SHIFT;
751 	p->header[1] |= KVASER_PCIEFD_TPACKET_AREQ;
752 
753 	if (can_is_canfd_skb(skb)) {
754 		p->header[1] |= KVASER_PCIEFD_RPACKET_FDF;
755 		if (cf->flags & CANFD_BRS)
756 			p->header[1] |= KVASER_PCIEFD_RPACKET_BRS;
757 		if (cf->flags & CANFD_ESI)
758 			p->header[1] |= KVASER_PCIEFD_RPACKET_ESI;
759 	}
760 
761 	p->header[1] |= seq & KVASER_PCIEFD_PACKET_SEQ_MSK;
762 
763 	packet_size = cf->len;
764 	memcpy(p->data, cf->data, packet_size);
765 
766 	return DIV_ROUND_UP(packet_size, 4);
767 }
768 
769 static netdev_tx_t kvaser_pciefd_start_xmit(struct sk_buff *skb,
770 					    struct net_device *netdev)
771 {
772 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
773 	unsigned long irq_flags;
774 	struct kvaser_pciefd_tx_packet packet;
775 	int nwords;
776 	u8 count;
777 
778 	if (can_dropped_invalid_skb(netdev, skb))
779 		return NETDEV_TX_OK;
780 
781 	nwords = kvaser_pciefd_prepare_tx_packet(&packet, can, skb);
782 
783 	spin_lock_irqsave(&can->echo_lock, irq_flags);
784 
785 	/* Prepare and save echo skb in internal slot */
786 	can_put_echo_skb(skb, netdev, can->echo_idx, 0);
787 
788 	/* Move echo index to the next slot */
789 	can->echo_idx = (can->echo_idx + 1) % can->can.echo_skb_max;
790 
791 	/* Write header to fifo */
792 	iowrite32(packet.header[0],
793 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
794 	iowrite32(packet.header[1],
795 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
796 
797 	if (nwords) {
798 		u32 data_last = ((u32 *)packet.data)[nwords - 1];
799 
800 		/* Write data to fifo, except last word */
801 		iowrite32_rep(can->reg_base +
802 			      KVASER_PCIEFD_KCAN_FIFO_REG, packet.data,
803 			      nwords - 1);
804 		/* Write last word to end of fifo */
805 		__raw_writel(data_last, can->reg_base +
806 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
807 	} else {
808 		/* Complete write to fifo */
809 		__raw_writel(0, can->reg_base +
810 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
811 	}
812 
813 	count = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
814 	/* No room for a new message, stop the queue until at least one
815 	 * successful transmit
816 	 */
817 	if (count >= KVASER_PCIEFD_CAN_TX_MAX_COUNT ||
818 	    can->can.echo_skb[can->echo_idx])
819 		netif_stop_queue(netdev);
820 
821 	spin_unlock_irqrestore(&can->echo_lock, irq_flags);
822 
823 	return NETDEV_TX_OK;
824 }
825 
826 static int kvaser_pciefd_set_bittiming(struct kvaser_pciefd_can *can, bool data)
827 {
828 	u32 mode, test, btrn;
829 	unsigned long irq_flags;
830 	int ret;
831 	struct can_bittiming *bt;
832 
833 	if (data)
834 		bt = &can->can.data_bittiming;
835 	else
836 		bt = &can->can.bittiming;
837 
838 	btrn = ((bt->phase_seg2 - 1) & 0x1f) <<
839 	       KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT |
840 	       (((bt->prop_seg + bt->phase_seg1) - 1) & 0x1ff) <<
841 	       KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT |
842 	       ((bt->sjw - 1) & 0xf) << KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT |
843 	       ((bt->brp - 1) & 0x1fff);
844 
845 	spin_lock_irqsave(&can->lock, irq_flags);
846 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
847 
848 	/* Put the circuit in reset mode */
849 	iowrite32(mode | KVASER_PCIEFD_KCAN_MODE_RM,
850 		  can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
851 
852 	/* Can only set bittiming if in reset mode */
853 	ret = readl_poll_timeout(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG,
854 				 test, test & KVASER_PCIEFD_KCAN_MODE_RM,
855 				 0, 10);
856 
857 	if (ret) {
858 		spin_unlock_irqrestore(&can->lock, irq_flags);
859 		return -EBUSY;
860 	}
861 
862 	if (data)
863 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRD_REG);
864 	else
865 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRN_REG);
866 
867 	/* Restore previous reset mode status */
868 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
869 
870 	spin_unlock_irqrestore(&can->lock, irq_flags);
871 	return 0;
872 }
873 
874 static int kvaser_pciefd_set_nominal_bittiming(struct net_device *ndev)
875 {
876 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), false);
877 }
878 
879 static int kvaser_pciefd_set_data_bittiming(struct net_device *ndev)
880 {
881 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), true);
882 }
883 
884 static int kvaser_pciefd_set_mode(struct net_device *ndev, enum can_mode mode)
885 {
886 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
887 	int ret = 0;
888 
889 	switch (mode) {
890 	case CAN_MODE_START:
891 		if (!can->can.restart_ms)
892 			ret = kvaser_pciefd_bus_on(can);
893 		break;
894 	default:
895 		return -EOPNOTSUPP;
896 	}
897 
898 	return ret;
899 }
900 
901 static int kvaser_pciefd_get_berr_counter(const struct net_device *ndev,
902 					  struct can_berr_counter *bec)
903 {
904 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
905 
906 	bec->rxerr = can->bec.rxerr;
907 	bec->txerr = can->bec.txerr;
908 	return 0;
909 }
910 
911 static void kvaser_pciefd_bec_poll_timer(struct timer_list *data)
912 {
913 	struct kvaser_pciefd_can *can = from_timer(can, data, bec_poll_timer);
914 
915 	kvaser_pciefd_enable_err_gen(can);
916 	kvaser_pciefd_request_status(can);
917 	can->err_rep_cnt = 0;
918 }
919 
920 static const struct net_device_ops kvaser_pciefd_netdev_ops = {
921 	.ndo_open = kvaser_pciefd_open,
922 	.ndo_stop = kvaser_pciefd_stop,
923 	.ndo_eth_ioctl = can_eth_ioctl_hwts,
924 	.ndo_start_xmit = kvaser_pciefd_start_xmit,
925 	.ndo_change_mtu = can_change_mtu,
926 };
927 
928 static const struct ethtool_ops kvaser_pciefd_ethtool_ops = {
929 	.get_ts_info = can_ethtool_op_get_ts_info_hwts,
930 };
931 
932 static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
933 {
934 	int i;
935 
936 	for (i = 0; i < pcie->nr_channels; i++) {
937 		struct net_device *netdev;
938 		struct kvaser_pciefd_can *can;
939 		u32 status, tx_npackets;
940 
941 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
942 				      KVASER_PCIEFD_CAN_TX_MAX_COUNT);
943 		if (!netdev)
944 			return -ENOMEM;
945 
946 		can = netdev_priv(netdev);
947 		netdev->netdev_ops = &kvaser_pciefd_netdev_ops;
948 		netdev->ethtool_ops = &kvaser_pciefd_ethtool_ops;
949 		can->reg_base = pcie->reg_base + KVASER_PCIEFD_KCAN0_BASE +
950 				i * KVASER_PCIEFD_KCAN_BASE_OFFSET;
951 
952 		can->kv_pcie = pcie;
953 		can->cmd_seq = 0;
954 		can->err_rep_cnt = 0;
955 		can->bec.txerr = 0;
956 		can->bec.rxerr = 0;
957 
958 		init_completion(&can->start_comp);
959 		init_completion(&can->flush_comp);
960 		timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer,
961 			    0);
962 
963 		/* Disable Bus load reporting */
964 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_BUS_LOAD_REG);
965 
966 		tx_npackets = ioread32(can->reg_base +
967 				       KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
968 		if (((tx_npackets >> KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT) &
969 		      0xff) < KVASER_PCIEFD_CAN_TX_MAX_COUNT) {
970 			dev_err(&pcie->pci->dev,
971 				"Max Tx count is smaller than expected\n");
972 
973 			free_candev(netdev);
974 			return -ENODEV;
975 		}
976 
977 		can->can.clock.freq = pcie->freq;
978 		can->can.echo_skb_max = KVASER_PCIEFD_CAN_TX_MAX_COUNT;
979 		can->echo_idx = 0;
980 		spin_lock_init(&can->echo_lock);
981 		spin_lock_init(&can->lock);
982 		can->can.bittiming_const = &kvaser_pciefd_bittiming_const;
983 		can->can.data_bittiming_const = &kvaser_pciefd_bittiming_const;
984 
985 		can->can.do_set_bittiming = kvaser_pciefd_set_nominal_bittiming;
986 		can->can.do_set_data_bittiming =
987 			kvaser_pciefd_set_data_bittiming;
988 
989 		can->can.do_set_mode = kvaser_pciefd_set_mode;
990 		can->can.do_get_berr_counter = kvaser_pciefd_get_berr_counter;
991 
992 		can->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
993 					      CAN_CTRLMODE_FD |
994 					      CAN_CTRLMODE_FD_NON_ISO;
995 
996 		status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
997 		if (!(status & KVASER_PCIEFD_KCAN_STAT_FD)) {
998 			dev_err(&pcie->pci->dev,
999 				"CAN FD not supported as expected %d\n", i);
1000 
1001 			free_candev(netdev);
1002 			return -ENODEV;
1003 		}
1004 
1005 		if (status & KVASER_PCIEFD_KCAN_STAT_CAP)
1006 			can->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1007 
1008 		netdev->flags |= IFF_ECHO;
1009 
1010 		SET_NETDEV_DEV(netdev, &pcie->pci->dev);
1011 
1012 		iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1013 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD |
1014 			  KVASER_PCIEFD_KCAN_IRQ_TFD,
1015 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1016 
1017 		pcie->can[i] = can;
1018 		kvaser_pciefd_pwm_start(can);
1019 	}
1020 
1021 	return 0;
1022 }
1023 
1024 static int kvaser_pciefd_reg_candev(struct kvaser_pciefd *pcie)
1025 {
1026 	int i;
1027 
1028 	for (i = 0; i < pcie->nr_channels; i++) {
1029 		int err = register_candev(pcie->can[i]->can.dev);
1030 
1031 		if (err) {
1032 			int j;
1033 
1034 			/* Unregister all successfully registered devices. */
1035 			for (j = 0; j < i; j++)
1036 				unregister_candev(pcie->can[j]->can.dev);
1037 			return err;
1038 		}
1039 	}
1040 
1041 	return 0;
1042 }
1043 
1044 static void kvaser_pciefd_write_dma_map(struct kvaser_pciefd *pcie,
1045 					dma_addr_t addr, int offset)
1046 {
1047 	u32 word1, word2;
1048 
1049 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
1050 	word1 = addr | KVASER_PCIEFD_64BIT_DMA_BIT;
1051 	word2 = addr >> 32;
1052 #else
1053 	word1 = addr;
1054 	word2 = 0;
1055 #endif
1056 	iowrite32(word1, pcie->reg_base + offset);
1057 	iowrite32(word2, pcie->reg_base + offset + 4);
1058 }
1059 
1060 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
1061 {
1062 	int i;
1063 	u32 srb_status;
1064 	dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
1065 
1066 	/* Disable the DMA */
1067 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1068 	for (i = 0; i < KVASER_PCIEFD_DMA_COUNT; i++) {
1069 		unsigned int offset = KVASER_PCIEFD_DMA_MAP_BASE + 8 * i;
1070 
1071 		pcie->dma_data[i] =
1072 			dmam_alloc_coherent(&pcie->pci->dev,
1073 					    KVASER_PCIEFD_DMA_SIZE,
1074 					    &dma_addr[i],
1075 					    GFP_KERNEL);
1076 
1077 		if (!pcie->dma_data[i] || !dma_addr[i]) {
1078 			dev_err(&pcie->pci->dev, "Rx dma_alloc(%u) failure\n",
1079 				KVASER_PCIEFD_DMA_SIZE);
1080 			return -ENOMEM;
1081 		}
1082 
1083 		kvaser_pciefd_write_dma_map(pcie, dma_addr[i], offset);
1084 	}
1085 
1086 	/* Reset Rx FIFO, and both DMA buffers */
1087 	iowrite32(KVASER_PCIEFD_SRB_CMD_FOR | KVASER_PCIEFD_SRB_CMD_RDB0 |
1088 		  KVASER_PCIEFD_SRB_CMD_RDB1,
1089 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1090 
1091 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1092 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
1093 		dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
1094 		return -EIO;
1095 	}
1096 
1097 	/* Enable the DMA */
1098 	iowrite32(KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE,
1099 		  pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1100 
1101 	return 0;
1102 }
1103 
1104 static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
1105 {
1106 	u32 sysid, srb_status, build;
1107 	u8 sysid_nr_chan;
1108 	int ret;
1109 
1110 	ret = kvaser_pciefd_read_cfg(pcie);
1111 	if (ret)
1112 		return ret;
1113 
1114 	sysid = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_VERSION_REG);
1115 	sysid_nr_chan = (sysid >> KVASER_PCIEFD_SYSID_NRCHAN_SHIFT) & 0xff;
1116 	if (pcie->nr_channels != sysid_nr_chan) {
1117 		dev_err(&pcie->pci->dev,
1118 			"Number of channels does not match: %u vs %u\n",
1119 			pcie->nr_channels,
1120 			sysid_nr_chan);
1121 		return -ENODEV;
1122 	}
1123 
1124 	if (pcie->nr_channels > KVASER_PCIEFD_MAX_CAN_CHANNELS)
1125 		pcie->nr_channels = KVASER_PCIEFD_MAX_CAN_CHANNELS;
1126 
1127 	build = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_BUILD_REG);
1128 	dev_dbg(&pcie->pci->dev, "Version %u.%u.%u\n",
1129 		(sysid >> KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT) & 0xff,
1130 		sysid & 0xff,
1131 		(build >> KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT) & 0x7fff);
1132 
1133 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1134 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DMA)) {
1135 		dev_err(&pcie->pci->dev,
1136 			"Hardware without DMA is not supported\n");
1137 		return -ENODEV;
1138 	}
1139 
1140 	pcie->bus_freq = ioread32(pcie->reg_base +
1141 				  KVASER_PCIEFD_SYSID_BUSFREQ_REG);
1142 	pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
1143 	pcie->freq_to_ticks_div = pcie->freq / 1000000;
1144 	if (pcie->freq_to_ticks_div == 0)
1145 		pcie->freq_to_ticks_div = 1;
1146 
1147 	/* Turn off all loopback functionality */
1148 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_LOOP_REG);
1149 	return ret;
1150 }
1151 
1152 static int kvaser_pciefd_handle_data_packet(struct kvaser_pciefd *pcie,
1153 					    struct kvaser_pciefd_rx_packet *p,
1154 					    __le32 *data)
1155 {
1156 	struct sk_buff *skb;
1157 	struct canfd_frame *cf;
1158 	struct can_priv *priv;
1159 	struct net_device_stats *stats;
1160 	struct skb_shared_hwtstamps *shhwtstamps;
1161 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1162 
1163 	if (ch_id >= pcie->nr_channels)
1164 		return -EIO;
1165 
1166 	priv = &pcie->can[ch_id]->can;
1167 	stats = &priv->dev->stats;
1168 
1169 	if (p->header[1] & KVASER_PCIEFD_RPACKET_FDF) {
1170 		skb = alloc_canfd_skb(priv->dev, &cf);
1171 		if (!skb) {
1172 			stats->rx_dropped++;
1173 			return -ENOMEM;
1174 		}
1175 
1176 		if (p->header[1] & KVASER_PCIEFD_RPACKET_BRS)
1177 			cf->flags |= CANFD_BRS;
1178 
1179 		if (p->header[1] & KVASER_PCIEFD_RPACKET_ESI)
1180 			cf->flags |= CANFD_ESI;
1181 	} else {
1182 		skb = alloc_can_skb(priv->dev, (struct can_frame **)&cf);
1183 		if (!skb) {
1184 			stats->rx_dropped++;
1185 			return -ENOMEM;
1186 		}
1187 	}
1188 
1189 	cf->can_id = p->header[0] & CAN_EFF_MASK;
1190 	if (p->header[0] & KVASER_PCIEFD_RPACKET_IDE)
1191 		cf->can_id |= CAN_EFF_FLAG;
1192 
1193 	cf->len = can_fd_dlc2len(p->header[1] >> KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1194 
1195 	if (p->header[0] & KVASER_PCIEFD_RPACKET_RTR) {
1196 		cf->can_id |= CAN_RTR_FLAG;
1197 	} else {
1198 		memcpy(cf->data, data, cf->len);
1199 
1200 		stats->rx_bytes += cf->len;
1201 	}
1202 	stats->rx_packets++;
1203 
1204 	shhwtstamps = skb_hwtstamps(skb);
1205 
1206 	shhwtstamps->hwtstamp =
1207 		ns_to_ktime(div_u64(p->timestamp * 1000,
1208 				    pcie->freq_to_ticks_div));
1209 
1210 	return netif_rx(skb);
1211 }
1212 
1213 static void kvaser_pciefd_change_state(struct kvaser_pciefd_can *can,
1214 				       struct can_frame *cf,
1215 				       enum can_state new_state,
1216 				       enum can_state tx_state,
1217 				       enum can_state rx_state)
1218 {
1219 	can_change_state(can->can.dev, cf, tx_state, rx_state);
1220 
1221 	if (new_state == CAN_STATE_BUS_OFF) {
1222 		struct net_device *ndev = can->can.dev;
1223 		unsigned long irq_flags;
1224 
1225 		spin_lock_irqsave(&can->lock, irq_flags);
1226 		netif_stop_queue(can->can.dev);
1227 		spin_unlock_irqrestore(&can->lock, irq_flags);
1228 
1229 		/* Prevent CAN controller from auto recover from bus off */
1230 		if (!can->can.restart_ms) {
1231 			kvaser_pciefd_start_controller_flush(can);
1232 			can_bus_off(ndev);
1233 		}
1234 	}
1235 }
1236 
1237 static void kvaser_pciefd_packet_to_state(struct kvaser_pciefd_rx_packet *p,
1238 					  struct can_berr_counter *bec,
1239 					  enum can_state *new_state,
1240 					  enum can_state *tx_state,
1241 					  enum can_state *rx_state)
1242 {
1243 	if (p->header[0] & KVASER_PCIEFD_SPACK_BOFF ||
1244 	    p->header[0] & KVASER_PCIEFD_SPACK_IRM)
1245 		*new_state = CAN_STATE_BUS_OFF;
1246 	else if (bec->txerr >= 255 ||  bec->rxerr >= 255)
1247 		*new_state = CAN_STATE_BUS_OFF;
1248 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EPLR)
1249 		*new_state = CAN_STATE_ERROR_PASSIVE;
1250 	else if (bec->txerr >= 128 || bec->rxerr >= 128)
1251 		*new_state = CAN_STATE_ERROR_PASSIVE;
1252 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EWLR)
1253 		*new_state = CAN_STATE_ERROR_WARNING;
1254 	else if (bec->txerr >= 96 || bec->rxerr >= 96)
1255 		*new_state = CAN_STATE_ERROR_WARNING;
1256 	else
1257 		*new_state = CAN_STATE_ERROR_ACTIVE;
1258 
1259 	*tx_state = bec->txerr >= bec->rxerr ? *new_state : 0;
1260 	*rx_state = bec->txerr <= bec->rxerr ? *new_state : 0;
1261 }
1262 
1263 static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
1264 					struct kvaser_pciefd_rx_packet *p)
1265 {
1266 	struct can_berr_counter bec;
1267 	enum can_state old_state, new_state, tx_state, rx_state;
1268 	struct net_device *ndev = can->can.dev;
1269 	struct sk_buff *skb;
1270 	struct can_frame *cf = NULL;
1271 	struct skb_shared_hwtstamps *shhwtstamps;
1272 	struct net_device_stats *stats = &ndev->stats;
1273 
1274 	old_state = can->can.state;
1275 
1276 	bec.txerr = p->header[0] & 0xff;
1277 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1278 
1279 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1280 				      &rx_state);
1281 
1282 	skb = alloc_can_err_skb(ndev, &cf);
1283 
1284 	if (new_state != old_state) {
1285 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1286 					   rx_state);
1287 
1288 		if (old_state == CAN_STATE_BUS_OFF &&
1289 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1290 		    can->can.restart_ms) {
1291 			can->can.can_stats.restarts++;
1292 			if (skb)
1293 				cf->can_id |= CAN_ERR_RESTARTED;
1294 		}
1295 	}
1296 
1297 	can->err_rep_cnt++;
1298 	can->can.can_stats.bus_error++;
1299 	if (p->header[1] & KVASER_PCIEFD_EPACK_DIR_TX)
1300 		stats->tx_errors++;
1301 	else
1302 		stats->rx_errors++;
1303 
1304 	can->bec.txerr = bec.txerr;
1305 	can->bec.rxerr = bec.rxerr;
1306 
1307 	if (!skb) {
1308 		stats->rx_dropped++;
1309 		return -ENOMEM;
1310 	}
1311 
1312 	shhwtstamps = skb_hwtstamps(skb);
1313 	shhwtstamps->hwtstamp =
1314 		ns_to_ktime(div_u64(p->timestamp * 1000,
1315 				    can->kv_pcie->freq_to_ticks_div));
1316 	cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT;
1317 
1318 	cf->data[6] = bec.txerr;
1319 	cf->data[7] = bec.rxerr;
1320 
1321 	netif_rx(skb);
1322 	return 0;
1323 }
1324 
1325 static int kvaser_pciefd_handle_error_packet(struct kvaser_pciefd *pcie,
1326 					     struct kvaser_pciefd_rx_packet *p)
1327 {
1328 	struct kvaser_pciefd_can *can;
1329 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1330 
1331 	if (ch_id >= pcie->nr_channels)
1332 		return -EIO;
1333 
1334 	can = pcie->can[ch_id];
1335 
1336 	kvaser_pciefd_rx_error_frame(can, p);
1337 	if (can->err_rep_cnt >= KVASER_PCIEFD_MAX_ERR_REP)
1338 		/* Do not report more errors, until bec_poll_timer expires */
1339 		kvaser_pciefd_disable_err_gen(can);
1340 	/* Start polling the error counters */
1341 	mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1342 	return 0;
1343 }
1344 
1345 static int kvaser_pciefd_handle_status_resp(struct kvaser_pciefd_can *can,
1346 					    struct kvaser_pciefd_rx_packet *p)
1347 {
1348 	struct can_berr_counter bec;
1349 	enum can_state old_state, new_state, tx_state, rx_state;
1350 
1351 	old_state = can->can.state;
1352 
1353 	bec.txerr = p->header[0] & 0xff;
1354 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1355 
1356 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1357 				      &rx_state);
1358 
1359 	if (new_state != old_state) {
1360 		struct net_device *ndev = can->can.dev;
1361 		struct sk_buff *skb;
1362 		struct can_frame *cf;
1363 		struct skb_shared_hwtstamps *shhwtstamps;
1364 
1365 		skb = alloc_can_err_skb(ndev, &cf);
1366 		if (!skb) {
1367 			struct net_device_stats *stats = &ndev->stats;
1368 
1369 			stats->rx_dropped++;
1370 			return -ENOMEM;
1371 		}
1372 
1373 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1374 					   rx_state);
1375 
1376 		if (old_state == CAN_STATE_BUS_OFF &&
1377 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1378 		    can->can.restart_ms) {
1379 			can->can.can_stats.restarts++;
1380 			cf->can_id |= CAN_ERR_RESTARTED;
1381 		}
1382 
1383 		shhwtstamps = skb_hwtstamps(skb);
1384 		shhwtstamps->hwtstamp =
1385 			ns_to_ktime(div_u64(p->timestamp * 1000,
1386 					    can->kv_pcie->freq_to_ticks_div));
1387 
1388 		cf->data[6] = bec.txerr;
1389 		cf->data[7] = bec.rxerr;
1390 
1391 		netif_rx(skb);
1392 	}
1393 	can->bec.txerr = bec.txerr;
1394 	can->bec.rxerr = bec.rxerr;
1395 	/* Check if we need to poll the error counters */
1396 	if (bec.txerr || bec.rxerr)
1397 		mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1398 
1399 	return 0;
1400 }
1401 
1402 static int kvaser_pciefd_handle_status_packet(struct kvaser_pciefd *pcie,
1403 					      struct kvaser_pciefd_rx_packet *p)
1404 {
1405 	struct kvaser_pciefd_can *can;
1406 	u8 cmdseq;
1407 	u32 status;
1408 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1409 
1410 	if (ch_id >= pcie->nr_channels)
1411 		return -EIO;
1412 
1413 	can = pcie->can[ch_id];
1414 
1415 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1416 	cmdseq = (status >> KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT) & 0xff;
1417 
1418 	/* Reset done, start abort and flush */
1419 	if (p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1420 	    p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1421 	    p->header[1] & KVASER_PCIEFD_SPACK_AUTO &&
1422 	    cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1423 	    status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1424 		u32 cmd;
1425 
1426 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1427 			  can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1428 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
1429 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
1430 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
1431 
1432 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_TFD,
1433 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1434 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET &&
1435 		   p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1436 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1437 		   status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1438 		/* Reset detected, send end of flush if no packet are in FIFO */
1439 		u8 count = ioread32(can->reg_base +
1440 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1441 
1442 		if (!count)
1443 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1444 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1445 	} else if (!(p->header[1] & KVASER_PCIEFD_SPACK_AUTO) &&
1446 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK)) {
1447 		/* Response to status request received */
1448 		kvaser_pciefd_handle_status_resp(can, p);
1449 		if (can->can.state != CAN_STATE_BUS_OFF &&
1450 		    can->can.state != CAN_STATE_ERROR_ACTIVE) {
1451 			mod_timer(&can->bec_poll_timer,
1452 				  KVASER_PCIEFD_BEC_POLL_FREQ);
1453 		}
1454 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1455 		   !(status & KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK)) {
1456 		/* Reset to bus on detected */
1457 		if (!completion_done(&can->start_comp))
1458 			complete(&can->start_comp);
1459 	}
1460 
1461 	return 0;
1462 }
1463 
1464 static int kvaser_pciefd_handle_eack_packet(struct kvaser_pciefd *pcie,
1465 					    struct kvaser_pciefd_rx_packet *p)
1466 {
1467 	struct kvaser_pciefd_can *can;
1468 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1469 
1470 	if (ch_id >= pcie->nr_channels)
1471 		return -EIO;
1472 
1473 	can = pcie->can[ch_id];
1474 
1475 	/* If this is the last flushed packet, send end of flush */
1476 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1477 		u8 count = ioread32(can->reg_base +
1478 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1479 
1480 		if (count == 0)
1481 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1482 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1483 	} else {
1484 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1485 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1486 		struct net_device_stats *stats = &can->can.dev->stats;
1487 
1488 		stats->tx_bytes += dlc;
1489 		stats->tx_packets++;
1490 
1491 		if (netif_queue_stopped(can->can.dev))
1492 			netif_wake_queue(can->can.dev);
1493 	}
1494 
1495 	return 0;
1496 }
1497 
1498 static void kvaser_pciefd_handle_nack_packet(struct kvaser_pciefd_can *can,
1499 					     struct kvaser_pciefd_rx_packet *p)
1500 {
1501 	struct sk_buff *skb;
1502 	struct net_device_stats *stats = &can->can.dev->stats;
1503 	struct can_frame *cf;
1504 
1505 	skb = alloc_can_err_skb(can->can.dev, &cf);
1506 
1507 	stats->tx_errors++;
1508 	if (p->header[0] & KVASER_PCIEFD_APACKET_ABL) {
1509 		if (skb)
1510 			cf->can_id |= CAN_ERR_LOSTARB;
1511 		can->can.can_stats.arbitration_lost++;
1512 	} else if (skb) {
1513 		cf->can_id |= CAN_ERR_ACK;
1514 	}
1515 
1516 	if (skb) {
1517 		cf->can_id |= CAN_ERR_BUSERROR;
1518 		netif_rx(skb);
1519 	} else {
1520 		stats->rx_dropped++;
1521 		netdev_warn(can->can.dev, "No memory left for err_skb\n");
1522 	}
1523 }
1524 
1525 static int kvaser_pciefd_handle_ack_packet(struct kvaser_pciefd *pcie,
1526 					   struct kvaser_pciefd_rx_packet *p)
1527 {
1528 	struct kvaser_pciefd_can *can;
1529 	bool one_shot_fail = false;
1530 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1531 
1532 	if (ch_id >= pcie->nr_channels)
1533 		return -EIO;
1534 
1535 	can = pcie->can[ch_id];
1536 	/* Ignore control packet ACK */
1537 	if (p->header[0] & KVASER_PCIEFD_APACKET_CT)
1538 		return 0;
1539 
1540 	if (p->header[0] & KVASER_PCIEFD_APACKET_NACK) {
1541 		kvaser_pciefd_handle_nack_packet(can, p);
1542 		one_shot_fail = true;
1543 	}
1544 
1545 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1546 		netdev_dbg(can->can.dev, "Packet was flushed\n");
1547 	} else {
1548 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1549 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1550 		u8 count = ioread32(can->reg_base +
1551 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1552 
1553 		if (count < KVASER_PCIEFD_CAN_TX_MAX_COUNT &&
1554 		    netif_queue_stopped(can->can.dev))
1555 			netif_wake_queue(can->can.dev);
1556 
1557 		if (!one_shot_fail) {
1558 			struct net_device_stats *stats = &can->can.dev->stats;
1559 
1560 			stats->tx_bytes += dlc;
1561 			stats->tx_packets++;
1562 		}
1563 	}
1564 
1565 	return 0;
1566 }
1567 
1568 static int kvaser_pciefd_handle_eflush_packet(struct kvaser_pciefd *pcie,
1569 					      struct kvaser_pciefd_rx_packet *p)
1570 {
1571 	struct kvaser_pciefd_can *can;
1572 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1573 
1574 	if (ch_id >= pcie->nr_channels)
1575 		return -EIO;
1576 
1577 	can = pcie->can[ch_id];
1578 
1579 	if (!completion_done(&can->flush_comp))
1580 		complete(&can->flush_comp);
1581 
1582 	return 0;
1583 }
1584 
1585 static int kvaser_pciefd_read_packet(struct kvaser_pciefd *pcie, int *start_pos,
1586 				     int dma_buf)
1587 {
1588 	__le32 *buffer = pcie->dma_data[dma_buf];
1589 	__le64 timestamp;
1590 	struct kvaser_pciefd_rx_packet packet;
1591 	struct kvaser_pciefd_rx_packet *p = &packet;
1592 	u8 type;
1593 	int pos = *start_pos;
1594 	int size;
1595 	int ret = 0;
1596 
1597 	size = le32_to_cpu(buffer[pos++]);
1598 	if (!size) {
1599 		*start_pos = 0;
1600 		return 0;
1601 	}
1602 
1603 	p->header[0] = le32_to_cpu(buffer[pos++]);
1604 	p->header[1] = le32_to_cpu(buffer[pos++]);
1605 
1606 	/* Read 64-bit timestamp */
1607 	memcpy(&timestamp, &buffer[pos], sizeof(__le64));
1608 	pos += 2;
1609 	p->timestamp = le64_to_cpu(timestamp);
1610 
1611 	type = (p->header[1] >> KVASER_PCIEFD_PACKET_TYPE_SHIFT) & 0xf;
1612 	switch (type) {
1613 	case KVASER_PCIEFD_PACK_TYPE_DATA:
1614 		ret = kvaser_pciefd_handle_data_packet(pcie, p, &buffer[pos]);
1615 		if (!(p->header[0] & KVASER_PCIEFD_RPACKET_RTR)) {
1616 			u8 data_len;
1617 
1618 			data_len = can_fd_dlc2len(p->header[1] >>
1619 					       KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1620 			pos += DIV_ROUND_UP(data_len, 4);
1621 		}
1622 		break;
1623 
1624 	case KVASER_PCIEFD_PACK_TYPE_ACK:
1625 		ret = kvaser_pciefd_handle_ack_packet(pcie, p);
1626 		break;
1627 
1628 	case KVASER_PCIEFD_PACK_TYPE_STATUS:
1629 		ret = kvaser_pciefd_handle_status_packet(pcie, p);
1630 		break;
1631 
1632 	case KVASER_PCIEFD_PACK_TYPE_ERROR:
1633 		ret = kvaser_pciefd_handle_error_packet(pcie, p);
1634 		break;
1635 
1636 	case KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK:
1637 		ret = kvaser_pciefd_handle_eack_packet(pcie, p);
1638 		break;
1639 
1640 	case KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK:
1641 		ret = kvaser_pciefd_handle_eflush_packet(pcie, p);
1642 		break;
1643 
1644 	case KVASER_PCIEFD_PACK_TYPE_ACK_DATA:
1645 	case KVASER_PCIEFD_PACK_TYPE_BUS_LOAD:
1646 	case KVASER_PCIEFD_PACK_TYPE_TXRQ:
1647 		dev_info(&pcie->pci->dev,
1648 			 "Received unexpected packet type 0x%08X\n", type);
1649 		break;
1650 
1651 	default:
1652 		dev_err(&pcie->pci->dev, "Unknown packet type 0x%08X\n", type);
1653 		ret = -EIO;
1654 		break;
1655 	}
1656 
1657 	if (ret)
1658 		return ret;
1659 
1660 	/* Position does not point to the end of the package,
1661 	 * corrupted packet size?
1662 	 */
1663 	if ((*start_pos + size) != pos)
1664 		return -EIO;
1665 
1666 	/* Point to the next packet header, if any */
1667 	*start_pos = pos;
1668 
1669 	return ret;
1670 }
1671 
1672 static int kvaser_pciefd_read_buffer(struct kvaser_pciefd *pcie, int dma_buf)
1673 {
1674 	int pos = 0;
1675 	int res = 0;
1676 
1677 	do {
1678 		res = kvaser_pciefd_read_packet(pcie, &pos, dma_buf);
1679 	} while (!res && pos > 0 && pos < KVASER_PCIEFD_DMA_SIZE);
1680 
1681 	return res;
1682 }
1683 
1684 static int kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
1685 {
1686 	u32 irq;
1687 
1688 	irq = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1689 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
1690 		kvaser_pciefd_read_buffer(pcie, 0);
1691 		/* Reset DMA buffer 0 */
1692 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1693 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1694 	}
1695 
1696 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
1697 		kvaser_pciefd_read_buffer(pcie, 1);
1698 		/* Reset DMA buffer 1 */
1699 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1700 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1701 	}
1702 
1703 	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
1704 	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
1705 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
1706 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
1707 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
1708 
1709 	iowrite32(irq, pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1710 	return 0;
1711 }
1712 
1713 static int kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
1714 {
1715 	u32 irq = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1716 
1717 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF)
1718 		netdev_err(can->can.dev, "Tx FIFO overflow\n");
1719 
1720 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TFD) {
1721 		u8 count = ioread32(can->reg_base +
1722 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1723 
1724 		if (count == 0)
1725 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1726 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1727 	}
1728 
1729 	if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP)
1730 		netdev_err(can->can.dev,
1731 			   "Fail to change bittiming, when not in reset mode\n");
1732 
1733 	if (irq & KVASER_PCIEFD_KCAN_IRQ_FDIC)
1734 		netdev_err(can->can.dev, "CAN FD frame in CAN mode\n");
1735 
1736 	if (irq & KVASER_PCIEFD_KCAN_IRQ_ROF)
1737 		netdev_err(can->can.dev, "Rx FIFO overflow\n");
1738 
1739 	iowrite32(irq, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1740 	return 0;
1741 }
1742 
1743 static irqreturn_t kvaser_pciefd_irq_handler(int irq, void *dev)
1744 {
1745 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
1746 	u32 board_irq;
1747 	int i;
1748 
1749 	board_irq = ioread32(pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1750 
1751 	if (!(board_irq & KVASER_PCIEFD_IRQ_ALL_MSK))
1752 		return IRQ_NONE;
1753 
1754 	if (board_irq & KVASER_PCIEFD_IRQ_SRB)
1755 		kvaser_pciefd_receive_irq(pcie);
1756 
1757 	for (i = 0; i < pcie->nr_channels; i++) {
1758 		if (!pcie->can[i]) {
1759 			dev_err(&pcie->pci->dev,
1760 				"IRQ mask points to unallocated controller\n");
1761 			break;
1762 		}
1763 
1764 		/* Check that mask matches channel (i) IRQ mask */
1765 		if (board_irq & (1 << i))
1766 			kvaser_pciefd_transmit_irq(pcie->can[i]);
1767 	}
1768 
1769 	iowrite32(board_irq, pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1770 	return IRQ_HANDLED;
1771 }
1772 
1773 static void kvaser_pciefd_teardown_can_ctrls(struct kvaser_pciefd *pcie)
1774 {
1775 	int i;
1776 	struct kvaser_pciefd_can *can;
1777 
1778 	for (i = 0; i < pcie->nr_channels; i++) {
1779 		can = pcie->can[i];
1780 		if (can) {
1781 			iowrite32(0,
1782 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1783 			kvaser_pciefd_pwm_stop(can);
1784 			free_candev(can->can.dev);
1785 		}
1786 	}
1787 }
1788 
1789 static int kvaser_pciefd_probe(struct pci_dev *pdev,
1790 			       const struct pci_device_id *id)
1791 {
1792 	int err;
1793 	struct kvaser_pciefd *pcie;
1794 
1795 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
1796 	if (!pcie)
1797 		return -ENOMEM;
1798 
1799 	pci_set_drvdata(pdev, pcie);
1800 	pcie->pci = pdev;
1801 
1802 	err = pci_enable_device(pdev);
1803 	if (err)
1804 		return err;
1805 
1806 	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
1807 	if (err)
1808 		goto err_disable_pci;
1809 
1810 	pcie->reg_base = pci_iomap(pdev, 0, 0);
1811 	if (!pcie->reg_base) {
1812 		err = -ENOMEM;
1813 		goto err_release_regions;
1814 	}
1815 
1816 	err = kvaser_pciefd_setup_board(pcie);
1817 	if (err)
1818 		goto err_pci_iounmap;
1819 
1820 	err = kvaser_pciefd_setup_dma(pcie);
1821 	if (err)
1822 		goto err_pci_iounmap;
1823 
1824 	pci_set_master(pdev);
1825 
1826 	err = kvaser_pciefd_setup_can_ctrls(pcie);
1827 	if (err)
1828 		goto err_teardown_can_ctrls;
1829 
1830 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
1831 		  pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1832 
1833 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1 |
1834 		  KVASER_PCIEFD_SRB_IRQ_DOF0 | KVASER_PCIEFD_SRB_IRQ_DOF1 |
1835 		  KVASER_PCIEFD_SRB_IRQ_DUF0 | KVASER_PCIEFD_SRB_IRQ_DUF1,
1836 		  pcie->reg_base + KVASER_PCIEFD_SRB_IEN_REG);
1837 
1838 	/* Reset IRQ handling, expected to be off before */
1839 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1840 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1841 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1842 		  pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1843 
1844 	/* Ready the DMA buffers */
1845 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1846 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1847 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1848 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1849 
1850 	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
1851 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
1852 	if (err)
1853 		goto err_teardown_can_ctrls;
1854 
1855 	err = kvaser_pciefd_reg_candev(pcie);
1856 	if (err)
1857 		goto err_free_irq;
1858 
1859 	return 0;
1860 
1861 err_free_irq:
1862 	free_irq(pcie->pci->irq, pcie);
1863 
1864 err_teardown_can_ctrls:
1865 	kvaser_pciefd_teardown_can_ctrls(pcie);
1866 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1867 	pci_clear_master(pdev);
1868 
1869 err_pci_iounmap:
1870 	pci_iounmap(pdev, pcie->reg_base);
1871 
1872 err_release_regions:
1873 	pci_release_regions(pdev);
1874 
1875 err_disable_pci:
1876 	pci_disable_device(pdev);
1877 
1878 	return err;
1879 }
1880 
1881 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
1882 {
1883 	struct kvaser_pciefd_can *can;
1884 	int i;
1885 
1886 	for (i = 0; i < pcie->nr_channels; i++) {
1887 		can = pcie->can[i];
1888 		if (can) {
1889 			iowrite32(0,
1890 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1891 			unregister_candev(can->can.dev);
1892 			del_timer(&can->bec_poll_timer);
1893 			kvaser_pciefd_pwm_stop(can);
1894 			free_candev(can->can.dev);
1895 		}
1896 	}
1897 }
1898 
1899 static void kvaser_pciefd_remove(struct pci_dev *pdev)
1900 {
1901 	struct kvaser_pciefd *pcie = pci_get_drvdata(pdev);
1902 
1903 	kvaser_pciefd_remove_all_ctrls(pcie);
1904 
1905 	/* Turn off IRQ generation */
1906 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1907 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1908 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1909 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1910 
1911 	free_irq(pcie->pci->irq, pcie);
1912 
1913 	pci_clear_master(pdev);
1914 	pci_iounmap(pdev, pcie->reg_base);
1915 	pci_release_regions(pdev);
1916 	pci_disable_device(pdev);
1917 }
1918 
1919 static struct pci_driver kvaser_pciefd = {
1920 	.name = KVASER_PCIEFD_DRV_NAME,
1921 	.id_table = kvaser_pciefd_id_table,
1922 	.probe = kvaser_pciefd_probe,
1923 	.remove = kvaser_pciefd_remove,
1924 };
1925 
1926 module_pci_driver(kvaser_pciefd)
1927