xref: /linux/drivers/net/can/kvaser_pciefd.c (revision 97d5f2e9ee12cdc7214d5835d35c59404cfafee6)
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_FIFO_LAST_REG (KVASER_PCIEFD_SRB_BASE + 0x1f4)
75 #define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
76 #define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
77 #define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
78 #define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
79 #define KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG (KVASER_PCIEFD_SRB_BASE + 0x214)
80 #define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
81 /* EPCS flash controller registers */
82 #define KVASER_PCIEFD_SPI_BASE 0x1fc00
83 #define KVASER_PCIEFD_SPI_RX_REG KVASER_PCIEFD_SPI_BASE
84 #define KVASER_PCIEFD_SPI_TX_REG (KVASER_PCIEFD_SPI_BASE + 0x4)
85 #define KVASER_PCIEFD_SPI_STATUS_REG (KVASER_PCIEFD_SPI_BASE + 0x8)
86 #define KVASER_PCIEFD_SPI_CTRL_REG (KVASER_PCIEFD_SPI_BASE + 0xc)
87 #define KVASER_PCIEFD_SPI_SSEL_REG (KVASER_PCIEFD_SPI_BASE + 0x14)
88 
89 #define KVASER_PCIEFD_IRQ_ALL_MSK 0x1f
90 #define KVASER_PCIEFD_IRQ_SRB BIT(4)
91 
92 #define KVASER_PCIEFD_SYSID_NRCHAN_SHIFT 24
93 #define KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT 16
94 #define KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT 1
95 
96 /* Reset DMA buffer 0, 1 and FIFO offset */
97 #define KVASER_PCIEFD_SRB_CMD_RDB0 BIT(4)
98 #define KVASER_PCIEFD_SRB_CMD_RDB1 BIT(5)
99 #define KVASER_PCIEFD_SRB_CMD_FOR BIT(0)
100 
101 /* DMA packet done, buffer 0 and 1 */
102 #define KVASER_PCIEFD_SRB_IRQ_DPD0 BIT(8)
103 #define KVASER_PCIEFD_SRB_IRQ_DPD1 BIT(9)
104 /* DMA overflow, buffer 0 and 1 */
105 #define KVASER_PCIEFD_SRB_IRQ_DOF0 BIT(10)
106 #define KVASER_PCIEFD_SRB_IRQ_DOF1 BIT(11)
107 /* DMA underflow, buffer 0 and 1 */
108 #define KVASER_PCIEFD_SRB_IRQ_DUF0 BIT(12)
109 #define KVASER_PCIEFD_SRB_IRQ_DUF1 BIT(13)
110 
111 /* DMA idle */
112 #define KVASER_PCIEFD_SRB_STAT_DI BIT(15)
113 /* DMA support */
114 #define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
115 
116 /* SRB current packet level */
117 #define KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK 0xff
118 
119 /* DMA Enable */
120 #define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
121 
122 /* EPCS flash controller definitions */
123 #define KVASER_PCIEFD_CFG_IMG_SZ (64 * 1024)
124 #define KVASER_PCIEFD_CFG_IMG_OFFSET (31 * 65536L)
125 #define KVASER_PCIEFD_CFG_MAX_PARAMS 256
126 #define KVASER_PCIEFD_CFG_MAGIC 0xcafef00d
127 #define KVASER_PCIEFD_CFG_PARAM_MAX_SZ 24
128 #define KVASER_PCIEFD_CFG_SYS_VER 1
129 #define KVASER_PCIEFD_CFG_PARAM_NR_CHAN 130
130 #define KVASER_PCIEFD_SPI_TMT BIT(5)
131 #define KVASER_PCIEFD_SPI_TRDY BIT(6)
132 #define KVASER_PCIEFD_SPI_RRDY BIT(7)
133 #define KVASER_PCIEFD_FLASH_ID_EPCS16 0x14
134 /* Commands for controlling the onboard flash */
135 #define KVASER_PCIEFD_FLASH_RES_CMD 0xab
136 #define KVASER_PCIEFD_FLASH_READ_CMD 0x3
137 #define KVASER_PCIEFD_FLASH_STATUS_CMD 0x5
138 
139 /* Kvaser KCAN definitions */
140 #define KVASER_PCIEFD_KCAN_CTRL_EFLUSH (4 << 29)
141 #define KVASER_PCIEFD_KCAN_CTRL_EFRAME (5 << 29)
142 
143 #define KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT 16
144 /* Request status packet */
145 #define KVASER_PCIEFD_KCAN_CMD_SRQ BIT(0)
146 /* Abort, flush and reset */
147 #define KVASER_PCIEFD_KCAN_CMD_AT BIT(1)
148 
149 /* Tx FIFO unaligned read */
150 #define KVASER_PCIEFD_KCAN_IRQ_TAR BIT(0)
151 /* Tx FIFO unaligned end */
152 #define KVASER_PCIEFD_KCAN_IRQ_TAE BIT(1)
153 /* Bus parameter protection error */
154 #define KVASER_PCIEFD_KCAN_IRQ_BPP BIT(2)
155 /* FDF bit when controller is in classic mode */
156 #define KVASER_PCIEFD_KCAN_IRQ_FDIC BIT(3)
157 /* Rx FIFO overflow */
158 #define KVASER_PCIEFD_KCAN_IRQ_ROF BIT(5)
159 /* Abort done */
160 #define KVASER_PCIEFD_KCAN_IRQ_ABD BIT(13)
161 /* Tx buffer flush done */
162 #define KVASER_PCIEFD_KCAN_IRQ_TFD BIT(14)
163 /* Tx FIFO overflow */
164 #define KVASER_PCIEFD_KCAN_IRQ_TOF BIT(15)
165 /* Tx FIFO empty */
166 #define KVASER_PCIEFD_KCAN_IRQ_TE BIT(16)
167 /* Transmitter unaligned */
168 #define KVASER_PCIEFD_KCAN_IRQ_TAL BIT(17)
169 
170 #define KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT 16
171 
172 #define KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT 24
173 /* Abort request */
174 #define KVASER_PCIEFD_KCAN_STAT_AR BIT(7)
175 /* Idle state. Controller in reset mode and no abort or flush pending */
176 #define KVASER_PCIEFD_KCAN_STAT_IDLE BIT(10)
177 /* Bus off */
178 #define KVASER_PCIEFD_KCAN_STAT_BOFF BIT(11)
179 /* Reset mode request */
180 #define KVASER_PCIEFD_KCAN_STAT_RMR BIT(14)
181 /* Controller in reset mode */
182 #define KVASER_PCIEFD_KCAN_STAT_IRM BIT(15)
183 /* Controller got one-shot capability */
184 #define KVASER_PCIEFD_KCAN_STAT_CAP BIT(16)
185 /* Controller got CAN FD capability */
186 #define KVASER_PCIEFD_KCAN_STAT_FD BIT(19)
187 #define KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK (KVASER_PCIEFD_KCAN_STAT_AR | \
188 	KVASER_PCIEFD_KCAN_STAT_BOFF | KVASER_PCIEFD_KCAN_STAT_RMR | \
189 	KVASER_PCIEFD_KCAN_STAT_IRM)
190 
191 /* Reset mode */
192 #define KVASER_PCIEFD_KCAN_MODE_RM BIT(8)
193 /* Listen only mode */
194 #define KVASER_PCIEFD_KCAN_MODE_LOM BIT(9)
195 /* Error packet enable */
196 #define KVASER_PCIEFD_KCAN_MODE_EPEN BIT(12)
197 /* CAN FD non-ISO */
198 #define KVASER_PCIEFD_KCAN_MODE_NIFDEN BIT(15)
199 /* Acknowledgment packet type */
200 #define KVASER_PCIEFD_KCAN_MODE_APT BIT(20)
201 /* Active error flag enable. Clear to force error passive */
202 #define KVASER_PCIEFD_KCAN_MODE_EEN BIT(23)
203 /* Classic CAN mode */
204 #define KVASER_PCIEFD_KCAN_MODE_CCM BIT(31)
205 
206 #define KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT 13
207 #define KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT 17
208 #define KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT 26
209 
210 #define KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT 16
211 
212 /* Kvaser KCAN packet types */
213 #define KVASER_PCIEFD_PACK_TYPE_DATA 0
214 #define KVASER_PCIEFD_PACK_TYPE_ACK 1
215 #define KVASER_PCIEFD_PACK_TYPE_TXRQ 2
216 #define KVASER_PCIEFD_PACK_TYPE_ERROR 3
217 #define KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK 4
218 #define KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK 5
219 #define KVASER_PCIEFD_PACK_TYPE_ACK_DATA 6
220 #define KVASER_PCIEFD_PACK_TYPE_STATUS 8
221 #define KVASER_PCIEFD_PACK_TYPE_BUS_LOAD 9
222 
223 /* Kvaser KCAN packet common definitions */
224 #define KVASER_PCIEFD_PACKET_SEQ_MSK 0xff
225 #define KVASER_PCIEFD_PACKET_CHID_SHIFT 25
226 #define KVASER_PCIEFD_PACKET_TYPE_SHIFT 28
227 
228 /* Kvaser KCAN TDATA and RDATA first word */
229 #define KVASER_PCIEFD_RPACKET_IDE BIT(30)
230 #define KVASER_PCIEFD_RPACKET_RTR BIT(29)
231 /* Kvaser KCAN TDATA and RDATA second word */
232 #define KVASER_PCIEFD_RPACKET_ESI BIT(13)
233 #define KVASER_PCIEFD_RPACKET_BRS BIT(14)
234 #define KVASER_PCIEFD_RPACKET_FDF BIT(15)
235 #define KVASER_PCIEFD_RPACKET_DLC_SHIFT 8
236 /* Kvaser KCAN TDATA second word */
237 #define KVASER_PCIEFD_TPACKET_SMS BIT(16)
238 #define KVASER_PCIEFD_TPACKET_AREQ BIT(31)
239 
240 /* Kvaser KCAN APACKET */
241 #define KVASER_PCIEFD_APACKET_FLU BIT(8)
242 #define KVASER_PCIEFD_APACKET_CT BIT(9)
243 #define KVASER_PCIEFD_APACKET_ABL BIT(10)
244 #define KVASER_PCIEFD_APACKET_NACK BIT(11)
245 
246 /* Kvaser KCAN SPACK first word */
247 #define KVASER_PCIEFD_SPACK_RXERR_SHIFT 8
248 #define KVASER_PCIEFD_SPACK_BOFF BIT(16)
249 #define KVASER_PCIEFD_SPACK_IDET BIT(20)
250 #define KVASER_PCIEFD_SPACK_IRM BIT(21)
251 #define KVASER_PCIEFD_SPACK_RMCD BIT(22)
252 /* Kvaser KCAN SPACK second word */
253 #define KVASER_PCIEFD_SPACK_AUTO BIT(21)
254 #define KVASER_PCIEFD_SPACK_EWLR BIT(23)
255 #define KVASER_PCIEFD_SPACK_EPLR BIT(24)
256 
257 /* Kvaser KCAN_EPACK second word */
258 #define KVASER_PCIEFD_EPACK_DIR_TX BIT(0)
259 
260 struct kvaser_pciefd;
261 
262 struct kvaser_pciefd_can {
263 	struct can_priv can;
264 	struct kvaser_pciefd *kv_pcie;
265 	void __iomem *reg_base;
266 	struct can_berr_counter bec;
267 	u8 cmd_seq;
268 	int err_rep_cnt;
269 	int echo_idx;
270 	spinlock_t lock; /* Locks sensitive registers (e.g. MODE) */
271 	spinlock_t echo_lock; /* Locks the message echo buffer */
272 	struct timer_list bec_poll_timer;
273 	struct completion start_comp, flush_comp;
274 };
275 
276 struct kvaser_pciefd {
277 	struct pci_dev *pci;
278 	void __iomem *reg_base;
279 	struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
280 	void *dma_data[KVASER_PCIEFD_DMA_COUNT];
281 	u8 nr_channels;
282 	u32 bus_freq;
283 	u32 freq;
284 	u32 freq_to_ticks_div;
285 };
286 
287 struct kvaser_pciefd_rx_packet {
288 	u32 header[2];
289 	u64 timestamp;
290 };
291 
292 struct kvaser_pciefd_tx_packet {
293 	u32 header[2];
294 	u8 data[64];
295 };
296 
297 static const struct can_bittiming_const kvaser_pciefd_bittiming_const = {
298 	.name = KVASER_PCIEFD_DRV_NAME,
299 	.tseg1_min = 1,
300 	.tseg1_max = 512,
301 	.tseg2_min = 1,
302 	.tseg2_max = 32,
303 	.sjw_max = 16,
304 	.brp_min = 1,
305 	.brp_max = 8192,
306 	.brp_inc = 1,
307 };
308 
309 struct kvaser_pciefd_cfg_param {
310 	__le32 magic;
311 	__le32 nr;
312 	__le32 len;
313 	u8 data[KVASER_PCIEFD_CFG_PARAM_MAX_SZ];
314 };
315 
316 struct kvaser_pciefd_cfg_img {
317 	__le32 version;
318 	__le32 magic;
319 	__le32 crc;
320 	struct kvaser_pciefd_cfg_param params[KVASER_PCIEFD_CFG_MAX_PARAMS];
321 };
322 
323 static struct pci_device_id kvaser_pciefd_id_table[] = {
324 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_4HS_ID), },
325 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_2HS_ID), },
326 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_HS_ID), },
327 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_HS_ID), },
328 	{ PCI_DEVICE(KVASER_PCIEFD_VENDOR, KVASER_PCIEFD_MINIPCIE_2HS_ID), },
329 	{ 0,},
330 };
331 MODULE_DEVICE_TABLE(pci, kvaser_pciefd_id_table);
332 
333 /* Onboard flash memory functions */
334 static int kvaser_pciefd_spi_wait_loop(struct kvaser_pciefd *pcie, int msk)
335 {
336 	u32 res;
337 
338 	return readl_poll_timeout(pcie->reg_base + KVASER_PCIEFD_SPI_STATUS_REG,
339 			res, res & msk, 0, 10);
340 }
341 
342 static int kvaser_pciefd_spi_cmd(struct kvaser_pciefd *pcie, const u8 *tx,
343 				 u32 tx_len, u8 *rx, u32 rx_len)
344 {
345 	int c;
346 
347 	iowrite32(BIT(0), pcie->reg_base + KVASER_PCIEFD_SPI_SSEL_REG);
348 	iowrite32(BIT(10), pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
349 	ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
350 
351 	c = tx_len;
352 	while (c--) {
353 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
354 			return -EIO;
355 
356 		iowrite32(*tx++, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
357 
358 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
359 			return -EIO;
360 
361 		ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
362 	}
363 
364 	c = rx_len;
365 	while (c-- > 0) {
366 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TRDY))
367 			return -EIO;
368 
369 		iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_TX_REG);
370 
371 		if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_RRDY))
372 			return -EIO;
373 
374 		*rx++ = ioread32(pcie->reg_base + KVASER_PCIEFD_SPI_RX_REG);
375 	}
376 
377 	if (kvaser_pciefd_spi_wait_loop(pcie, KVASER_PCIEFD_SPI_TMT))
378 		return -EIO;
379 
380 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SPI_CTRL_REG);
381 
382 	if (c != -1) {
383 		dev_err(&pcie->pci->dev, "Flash SPI transfer failed\n");
384 		return -EIO;
385 	}
386 
387 	return 0;
388 }
389 
390 static int kvaser_pciefd_cfg_read_and_verify(struct kvaser_pciefd *pcie,
391 					     struct kvaser_pciefd_cfg_img *img)
392 {
393 	int offset = KVASER_PCIEFD_CFG_IMG_OFFSET;
394 	int res, crc;
395 	u8 *crc_buff;
396 
397 	u8 cmd[] = {
398 		KVASER_PCIEFD_FLASH_READ_CMD,
399 		(u8)((offset >> 16) & 0xff),
400 		(u8)((offset >> 8) & 0xff),
401 		(u8)(offset & 0xff)
402 	};
403 
404 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), (u8 *)img,
405 				    KVASER_PCIEFD_CFG_IMG_SZ);
406 	if (res)
407 		return res;
408 
409 	crc_buff = (u8 *)img->params;
410 
411 	if (le32_to_cpu(img->version) != KVASER_PCIEFD_CFG_SYS_VER) {
412 		dev_err(&pcie->pci->dev,
413 			"Config flash corrupted, version number is wrong\n");
414 		return -ENODEV;
415 	}
416 
417 	if (le32_to_cpu(img->magic) != KVASER_PCIEFD_CFG_MAGIC) {
418 		dev_err(&pcie->pci->dev,
419 			"Config flash corrupted, magic number is wrong\n");
420 		return -ENODEV;
421 	}
422 
423 	crc = ~crc32_be(0xffffffff, crc_buff, sizeof(img->params));
424 	if (le32_to_cpu(img->crc) != crc) {
425 		dev_err(&pcie->pci->dev,
426 			"Stored CRC does not match flash image contents\n");
427 		return -EIO;
428 	}
429 
430 	return 0;
431 }
432 
433 static void kvaser_pciefd_cfg_read_params(struct kvaser_pciefd *pcie,
434 					  struct kvaser_pciefd_cfg_img *img)
435 {
436 	struct kvaser_pciefd_cfg_param *param;
437 
438 	param = &img->params[KVASER_PCIEFD_CFG_PARAM_NR_CHAN];
439 	memcpy(&pcie->nr_channels, param->data, le32_to_cpu(param->len));
440 }
441 
442 static int kvaser_pciefd_read_cfg(struct kvaser_pciefd *pcie)
443 {
444 	int res;
445 	struct kvaser_pciefd_cfg_img *img;
446 
447 	/* Read electronic signature */
448 	u8 cmd[] = {KVASER_PCIEFD_FLASH_RES_CMD, 0, 0, 0};
449 
450 	res = kvaser_pciefd_spi_cmd(pcie, cmd, ARRAY_SIZE(cmd), cmd, 1);
451 	if (res)
452 		return -EIO;
453 
454 	img = kmalloc(KVASER_PCIEFD_CFG_IMG_SZ, GFP_KERNEL);
455 	if (!img)
456 		return -ENOMEM;
457 
458 	if (cmd[0] != KVASER_PCIEFD_FLASH_ID_EPCS16) {
459 		dev_err(&pcie->pci->dev,
460 			"Flash id is 0x%x instead of expected EPCS16 (0x%x)\n",
461 			cmd[0], KVASER_PCIEFD_FLASH_ID_EPCS16);
462 
463 		res = -ENODEV;
464 		goto image_free;
465 	}
466 
467 	cmd[0] = KVASER_PCIEFD_FLASH_STATUS_CMD;
468 	res = kvaser_pciefd_spi_cmd(pcie, cmd, 1, cmd, 1);
469 	if (res) {
470 		goto image_free;
471 	} else if (cmd[0] & 1) {
472 		res = -EIO;
473 		/* No write is ever done, the WIP should never be set */
474 		dev_err(&pcie->pci->dev, "Unexpected WIP bit set in flash\n");
475 		goto image_free;
476 	}
477 
478 	res = kvaser_pciefd_cfg_read_and_verify(pcie, img);
479 	if (res) {
480 		res = -EIO;
481 		goto image_free;
482 	}
483 
484 	kvaser_pciefd_cfg_read_params(pcie, img);
485 
486 image_free:
487 	kfree(img);
488 	return res;
489 }
490 
491 static void kvaser_pciefd_request_status(struct kvaser_pciefd_can *can)
492 {
493 	u32 cmd;
494 
495 	cmd = KVASER_PCIEFD_KCAN_CMD_SRQ;
496 	cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
497 	iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
498 }
499 
500 static void kvaser_pciefd_enable_err_gen(struct kvaser_pciefd_can *can)
501 {
502 	u32 mode;
503 	unsigned long irq;
504 
505 	spin_lock_irqsave(&can->lock, irq);
506 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
507 	if (!(mode & KVASER_PCIEFD_KCAN_MODE_EPEN)) {
508 		mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
509 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
510 	}
511 	spin_unlock_irqrestore(&can->lock, irq);
512 }
513 
514 static void kvaser_pciefd_disable_err_gen(struct kvaser_pciefd_can *can)
515 {
516 	u32 mode;
517 	unsigned long irq;
518 
519 	spin_lock_irqsave(&can->lock, irq);
520 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
521 	mode &= ~KVASER_PCIEFD_KCAN_MODE_EPEN;
522 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
523 	spin_unlock_irqrestore(&can->lock, irq);
524 }
525 
526 static int kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
527 {
528 	u32 msk;
529 
530 	msk = KVASER_PCIEFD_KCAN_IRQ_TE | KVASER_PCIEFD_KCAN_IRQ_ROF |
531 	      KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD |
532 	      KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL |
533 	      KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP |
534 	      KVASER_PCIEFD_KCAN_IRQ_TAR;
535 
536 	iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
537 
538 	return 0;
539 }
540 
541 static void kvaser_pciefd_setup_controller(struct kvaser_pciefd_can *can)
542 {
543 	u32 mode;
544 	unsigned long irq;
545 
546 	spin_lock_irqsave(&can->lock, irq);
547 
548 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
549 	if (can->can.ctrlmode & CAN_CTRLMODE_FD) {
550 		mode &= ~KVASER_PCIEFD_KCAN_MODE_CCM;
551 		if (can->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
552 			mode |= KVASER_PCIEFD_KCAN_MODE_NIFDEN;
553 		else
554 			mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
555 	} else {
556 		mode |= KVASER_PCIEFD_KCAN_MODE_CCM;
557 		mode &= ~KVASER_PCIEFD_KCAN_MODE_NIFDEN;
558 	}
559 
560 	if (can->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
561 		mode |= KVASER_PCIEFD_KCAN_MODE_LOM;
562 	else
563 		mode &= ~KVASER_PCIEFD_KCAN_MODE_LOM;
564 
565 	mode |= KVASER_PCIEFD_KCAN_MODE_EEN;
566 	mode |= KVASER_PCIEFD_KCAN_MODE_EPEN;
567 	/* Use ACK packet type */
568 	mode &= ~KVASER_PCIEFD_KCAN_MODE_APT;
569 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
570 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
571 
572 	spin_unlock_irqrestore(&can->lock, irq);
573 }
574 
575 static void kvaser_pciefd_start_controller_flush(struct kvaser_pciefd_can *can)
576 {
577 	u32 status;
578 	unsigned long irq;
579 
580 	spin_lock_irqsave(&can->lock, irq);
581 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
582 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
583 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
584 
585 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
586 	if (status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
587 		u32 cmd;
588 
589 		/* If controller is already idle, run abort, flush and reset */
590 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
591 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
592 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
593 	} else if (!(status & KVASER_PCIEFD_KCAN_STAT_RMR)) {
594 		u32 mode;
595 
596 		/* Put controller in reset mode */
597 		mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
598 		mode |= KVASER_PCIEFD_KCAN_MODE_RM;
599 		iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
600 	}
601 
602 	spin_unlock_irqrestore(&can->lock, irq);
603 }
604 
605 static int kvaser_pciefd_bus_on(struct kvaser_pciefd_can *can)
606 {
607 	u32 mode;
608 	unsigned long irq;
609 
610 	del_timer(&can->bec_poll_timer);
611 
612 	if (!completion_done(&can->flush_comp))
613 		kvaser_pciefd_start_controller_flush(can);
614 
615 	if (!wait_for_completion_timeout(&can->flush_comp,
616 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
617 		netdev_err(can->can.dev, "Timeout during bus on flush\n");
618 		return -ETIMEDOUT;
619 	}
620 
621 	spin_lock_irqsave(&can->lock, irq);
622 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
623 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
624 
625 	iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
626 		  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
627 
628 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
629 	mode &= ~KVASER_PCIEFD_KCAN_MODE_RM;
630 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
631 	spin_unlock_irqrestore(&can->lock, irq);
632 
633 	if (!wait_for_completion_timeout(&can->start_comp,
634 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
635 		netdev_err(can->can.dev, "Timeout during bus on reset\n");
636 		return -ETIMEDOUT;
637 	}
638 	/* Reset interrupt handling */
639 	iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
640 	iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
641 
642 	kvaser_pciefd_set_tx_irq(can);
643 	kvaser_pciefd_setup_controller(can);
644 
645 	can->can.state = CAN_STATE_ERROR_ACTIVE;
646 	netif_wake_queue(can->can.dev);
647 	can->bec.txerr = 0;
648 	can->bec.rxerr = 0;
649 	can->err_rep_cnt = 0;
650 
651 	return 0;
652 }
653 
654 static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
655 {
656 	u8 top;
657 	u32 pwm_ctrl;
658 	unsigned long irq;
659 
660 	spin_lock_irqsave(&can->lock, irq);
661 	pwm_ctrl = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
662 	top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;
663 
664 	/* Set duty cycle to zero */
665 	pwm_ctrl |= top;
666 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
667 	spin_unlock_irqrestore(&can->lock, irq);
668 }
669 
670 static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
671 {
672 	int top, trigger;
673 	u32 pwm_ctrl;
674 	unsigned long irq;
675 
676 	kvaser_pciefd_pwm_stop(can);
677 	spin_lock_irqsave(&can->lock, irq);
678 
679 	/* Set frequency to 500 KHz*/
680 	top = can->kv_pcie->bus_freq / (2 * 500000) - 1;
681 
682 	pwm_ctrl = top & 0xff;
683 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
684 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
685 
686 	/* Set duty cycle to 95 */
687 	trigger = (100 * top - 95 * (top + 1) + 50) / 100;
688 	pwm_ctrl = trigger & 0xff;
689 	pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
690 	iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
691 	spin_unlock_irqrestore(&can->lock, irq);
692 }
693 
694 static int kvaser_pciefd_open(struct net_device *netdev)
695 {
696 	int err;
697 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
698 
699 	err = open_candev(netdev);
700 	if (err)
701 		return err;
702 
703 	err = kvaser_pciefd_bus_on(can);
704 	if (err) {
705 		close_candev(netdev);
706 		return err;
707 	}
708 
709 	return 0;
710 }
711 
712 static int kvaser_pciefd_stop(struct net_device *netdev)
713 {
714 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
715 	int ret = 0;
716 
717 	/* Don't interrupt ongoing flush */
718 	if (!completion_done(&can->flush_comp))
719 		kvaser_pciefd_start_controller_flush(can);
720 
721 	if (!wait_for_completion_timeout(&can->flush_comp,
722 					 KVASER_PCIEFD_WAIT_TIMEOUT)) {
723 		netdev_err(can->can.dev, "Timeout during stop\n");
724 		ret = -ETIMEDOUT;
725 	} else {
726 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
727 		del_timer(&can->bec_poll_timer);
728 	}
729 	can->can.state = CAN_STATE_STOPPED;
730 	close_candev(netdev);
731 
732 	return ret;
733 }
734 
735 static int kvaser_pciefd_prepare_tx_packet(struct kvaser_pciefd_tx_packet *p,
736 					   struct kvaser_pciefd_can *can,
737 					   struct sk_buff *skb)
738 {
739 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
740 	int packet_size;
741 	int seq = can->echo_idx;
742 
743 	memset(p, 0, sizeof(*p));
744 
745 	if (can->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
746 		p->header[1] |= KVASER_PCIEFD_TPACKET_SMS;
747 
748 	if (cf->can_id & CAN_RTR_FLAG)
749 		p->header[0] |= KVASER_PCIEFD_RPACKET_RTR;
750 
751 	if (cf->can_id & CAN_EFF_FLAG)
752 		p->header[0] |= KVASER_PCIEFD_RPACKET_IDE;
753 
754 	p->header[0] |= cf->can_id & CAN_EFF_MASK;
755 	p->header[1] |= can_fd_len2dlc(cf->len) << KVASER_PCIEFD_RPACKET_DLC_SHIFT;
756 	p->header[1] |= KVASER_PCIEFD_TPACKET_AREQ;
757 
758 	if (can_is_canfd_skb(skb)) {
759 		p->header[1] |= KVASER_PCIEFD_RPACKET_FDF;
760 		if (cf->flags & CANFD_BRS)
761 			p->header[1] |= KVASER_PCIEFD_RPACKET_BRS;
762 		if (cf->flags & CANFD_ESI)
763 			p->header[1] |= KVASER_PCIEFD_RPACKET_ESI;
764 	}
765 
766 	p->header[1] |= seq & KVASER_PCIEFD_PACKET_SEQ_MSK;
767 
768 	packet_size = cf->len;
769 	memcpy(p->data, cf->data, packet_size);
770 
771 	return DIV_ROUND_UP(packet_size, 4);
772 }
773 
774 static netdev_tx_t kvaser_pciefd_start_xmit(struct sk_buff *skb,
775 					    struct net_device *netdev)
776 {
777 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
778 	unsigned long irq_flags;
779 	struct kvaser_pciefd_tx_packet packet;
780 	int nwords;
781 	u8 count;
782 
783 	if (can_dev_dropped_skb(netdev, skb))
784 		return NETDEV_TX_OK;
785 
786 	nwords = kvaser_pciefd_prepare_tx_packet(&packet, can, skb);
787 
788 	spin_lock_irqsave(&can->echo_lock, irq_flags);
789 
790 	/* Prepare and save echo skb in internal slot */
791 	can_put_echo_skb(skb, netdev, can->echo_idx, 0);
792 
793 	/* Move echo index to the next slot */
794 	can->echo_idx = (can->echo_idx + 1) % can->can.echo_skb_max;
795 
796 	/* Write header to fifo */
797 	iowrite32(packet.header[0],
798 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
799 	iowrite32(packet.header[1],
800 		  can->reg_base + KVASER_PCIEFD_KCAN_FIFO_REG);
801 
802 	if (nwords) {
803 		u32 data_last = ((u32 *)packet.data)[nwords - 1];
804 
805 		/* Write data to fifo, except last word */
806 		iowrite32_rep(can->reg_base +
807 			      KVASER_PCIEFD_KCAN_FIFO_REG, packet.data,
808 			      nwords - 1);
809 		/* Write last word to end of fifo */
810 		__raw_writel(data_last, can->reg_base +
811 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
812 	} else {
813 		/* Complete write to fifo */
814 		__raw_writel(0, can->reg_base +
815 			     KVASER_PCIEFD_KCAN_FIFO_LAST_REG);
816 	}
817 
818 	count = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
819 	/* No room for a new message, stop the queue until at least one
820 	 * successful transmit
821 	 */
822 	if (count >= KVASER_PCIEFD_CAN_TX_MAX_COUNT ||
823 	    can->can.echo_skb[can->echo_idx])
824 		netif_stop_queue(netdev);
825 
826 	spin_unlock_irqrestore(&can->echo_lock, irq_flags);
827 
828 	return NETDEV_TX_OK;
829 }
830 
831 static int kvaser_pciefd_set_bittiming(struct kvaser_pciefd_can *can, bool data)
832 {
833 	u32 mode, test, btrn;
834 	unsigned long irq_flags;
835 	int ret;
836 	struct can_bittiming *bt;
837 
838 	if (data)
839 		bt = &can->can.data_bittiming;
840 	else
841 		bt = &can->can.bittiming;
842 
843 	btrn = ((bt->phase_seg2 - 1) & 0x1f) <<
844 	       KVASER_PCIEFD_KCAN_BTRN_TSEG2_SHIFT |
845 	       (((bt->prop_seg + bt->phase_seg1) - 1) & 0x1ff) <<
846 	       KVASER_PCIEFD_KCAN_BTRN_TSEG1_SHIFT |
847 	       ((bt->sjw - 1) & 0xf) << KVASER_PCIEFD_KCAN_BTRN_SJW_SHIFT |
848 	       ((bt->brp - 1) & 0x1fff);
849 
850 	spin_lock_irqsave(&can->lock, irq_flags);
851 	mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
852 
853 	/* Put the circuit in reset mode */
854 	iowrite32(mode | KVASER_PCIEFD_KCAN_MODE_RM,
855 		  can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
856 
857 	/* Can only set bittiming if in reset mode */
858 	ret = readl_poll_timeout(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG,
859 				 test, test & KVASER_PCIEFD_KCAN_MODE_RM,
860 				 0, 10);
861 
862 	if (ret) {
863 		spin_unlock_irqrestore(&can->lock, irq_flags);
864 		return -EBUSY;
865 	}
866 
867 	if (data)
868 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRD_REG);
869 	else
870 		iowrite32(btrn, can->reg_base + KVASER_PCIEFD_KCAN_BTRN_REG);
871 
872 	/* Restore previous reset mode status */
873 	iowrite32(mode, can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG);
874 
875 	spin_unlock_irqrestore(&can->lock, irq_flags);
876 	return 0;
877 }
878 
879 static int kvaser_pciefd_set_nominal_bittiming(struct net_device *ndev)
880 {
881 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), false);
882 }
883 
884 static int kvaser_pciefd_set_data_bittiming(struct net_device *ndev)
885 {
886 	return kvaser_pciefd_set_bittiming(netdev_priv(ndev), true);
887 }
888 
889 static int kvaser_pciefd_set_mode(struct net_device *ndev, enum can_mode mode)
890 {
891 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
892 	int ret = 0;
893 
894 	switch (mode) {
895 	case CAN_MODE_START:
896 		if (!can->can.restart_ms)
897 			ret = kvaser_pciefd_bus_on(can);
898 		break;
899 	default:
900 		return -EOPNOTSUPP;
901 	}
902 
903 	return ret;
904 }
905 
906 static int kvaser_pciefd_get_berr_counter(const struct net_device *ndev,
907 					  struct can_berr_counter *bec)
908 {
909 	struct kvaser_pciefd_can *can = netdev_priv(ndev);
910 
911 	bec->rxerr = can->bec.rxerr;
912 	bec->txerr = can->bec.txerr;
913 	return 0;
914 }
915 
916 static void kvaser_pciefd_bec_poll_timer(struct timer_list *data)
917 {
918 	struct kvaser_pciefd_can *can = from_timer(can, data, bec_poll_timer);
919 
920 	kvaser_pciefd_enable_err_gen(can);
921 	kvaser_pciefd_request_status(can);
922 	can->err_rep_cnt = 0;
923 }
924 
925 static const struct net_device_ops kvaser_pciefd_netdev_ops = {
926 	.ndo_open = kvaser_pciefd_open,
927 	.ndo_stop = kvaser_pciefd_stop,
928 	.ndo_eth_ioctl = can_eth_ioctl_hwts,
929 	.ndo_start_xmit = kvaser_pciefd_start_xmit,
930 	.ndo_change_mtu = can_change_mtu,
931 };
932 
933 static const struct ethtool_ops kvaser_pciefd_ethtool_ops = {
934 	.get_ts_info = can_ethtool_op_get_ts_info_hwts,
935 };
936 
937 static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
938 {
939 	int i;
940 
941 	for (i = 0; i < pcie->nr_channels; i++) {
942 		struct net_device *netdev;
943 		struct kvaser_pciefd_can *can;
944 		u32 status, tx_npackets;
945 
946 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
947 				      KVASER_PCIEFD_CAN_TX_MAX_COUNT);
948 		if (!netdev)
949 			return -ENOMEM;
950 
951 		can = netdev_priv(netdev);
952 		netdev->netdev_ops = &kvaser_pciefd_netdev_ops;
953 		netdev->ethtool_ops = &kvaser_pciefd_ethtool_ops;
954 		can->reg_base = pcie->reg_base + KVASER_PCIEFD_KCAN0_BASE +
955 				i * KVASER_PCIEFD_KCAN_BASE_OFFSET;
956 
957 		can->kv_pcie = pcie;
958 		can->cmd_seq = 0;
959 		can->err_rep_cnt = 0;
960 		can->bec.txerr = 0;
961 		can->bec.rxerr = 0;
962 
963 		init_completion(&can->start_comp);
964 		init_completion(&can->flush_comp);
965 		timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer,
966 			    0);
967 
968 		/* Disable Bus load reporting */
969 		iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_BUS_LOAD_REG);
970 
971 		tx_npackets = ioread32(can->reg_base +
972 				       KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
973 		if (((tx_npackets >> KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT) &
974 		      0xff) < KVASER_PCIEFD_CAN_TX_MAX_COUNT) {
975 			dev_err(&pcie->pci->dev,
976 				"Max Tx count is smaller than expected\n");
977 
978 			free_candev(netdev);
979 			return -ENODEV;
980 		}
981 
982 		can->can.clock.freq = pcie->freq;
983 		can->can.echo_skb_max = KVASER_PCIEFD_CAN_TX_MAX_COUNT;
984 		can->echo_idx = 0;
985 		spin_lock_init(&can->echo_lock);
986 		spin_lock_init(&can->lock);
987 		can->can.bittiming_const = &kvaser_pciefd_bittiming_const;
988 		can->can.data_bittiming_const = &kvaser_pciefd_bittiming_const;
989 
990 		can->can.do_set_bittiming = kvaser_pciefd_set_nominal_bittiming;
991 		can->can.do_set_data_bittiming =
992 			kvaser_pciefd_set_data_bittiming;
993 
994 		can->can.do_set_mode = kvaser_pciefd_set_mode;
995 		can->can.do_get_berr_counter = kvaser_pciefd_get_berr_counter;
996 
997 		can->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
998 					      CAN_CTRLMODE_FD |
999 					      CAN_CTRLMODE_FD_NON_ISO;
1000 
1001 		status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1002 		if (!(status & KVASER_PCIEFD_KCAN_STAT_FD)) {
1003 			dev_err(&pcie->pci->dev,
1004 				"CAN FD not supported as expected %d\n", i);
1005 
1006 			free_candev(netdev);
1007 			return -ENODEV;
1008 		}
1009 
1010 		if (status & KVASER_PCIEFD_KCAN_STAT_CAP)
1011 			can->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1012 
1013 		netdev->flags |= IFF_ECHO;
1014 
1015 		SET_NETDEV_DEV(netdev, &pcie->pci->dev);
1016 
1017 		iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1018 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1019 			  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1020 
1021 		pcie->can[i] = can;
1022 		kvaser_pciefd_pwm_start(can);
1023 	}
1024 
1025 	return 0;
1026 }
1027 
1028 static int kvaser_pciefd_reg_candev(struct kvaser_pciefd *pcie)
1029 {
1030 	int i;
1031 
1032 	for (i = 0; i < pcie->nr_channels; i++) {
1033 		int err = register_candev(pcie->can[i]->can.dev);
1034 
1035 		if (err) {
1036 			int j;
1037 
1038 			/* Unregister all successfully registered devices. */
1039 			for (j = 0; j < i; j++)
1040 				unregister_candev(pcie->can[j]->can.dev);
1041 			return err;
1042 		}
1043 	}
1044 
1045 	return 0;
1046 }
1047 
1048 static void kvaser_pciefd_write_dma_map(struct kvaser_pciefd *pcie,
1049 					dma_addr_t addr, int offset)
1050 {
1051 	u32 word1, word2;
1052 
1053 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
1054 	word1 = addr | KVASER_PCIEFD_64BIT_DMA_BIT;
1055 	word2 = addr >> 32;
1056 #else
1057 	word1 = addr;
1058 	word2 = 0;
1059 #endif
1060 	iowrite32(word1, pcie->reg_base + offset);
1061 	iowrite32(word2, pcie->reg_base + offset + 4);
1062 }
1063 
1064 static int kvaser_pciefd_setup_dma(struct kvaser_pciefd *pcie)
1065 {
1066 	int i;
1067 	u32 srb_status;
1068 	u32 srb_packet_count;
1069 	dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
1070 
1071 	/* Disable the DMA */
1072 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1073 	for (i = 0; i < KVASER_PCIEFD_DMA_COUNT; i++) {
1074 		unsigned int offset = KVASER_PCIEFD_DMA_MAP_BASE + 8 * i;
1075 
1076 		pcie->dma_data[i] =
1077 			dmam_alloc_coherent(&pcie->pci->dev,
1078 					    KVASER_PCIEFD_DMA_SIZE,
1079 					    &dma_addr[i],
1080 					    GFP_KERNEL);
1081 
1082 		if (!pcie->dma_data[i] || !dma_addr[i]) {
1083 			dev_err(&pcie->pci->dev, "Rx dma_alloc(%u) failure\n",
1084 				KVASER_PCIEFD_DMA_SIZE);
1085 			return -ENOMEM;
1086 		}
1087 
1088 		kvaser_pciefd_write_dma_map(pcie, dma_addr[i], offset);
1089 	}
1090 
1091 	/* Reset Rx FIFO, and both DMA buffers */
1092 	iowrite32(KVASER_PCIEFD_SRB_CMD_FOR | KVASER_PCIEFD_SRB_CMD_RDB0 |
1093 		  KVASER_PCIEFD_SRB_CMD_RDB1,
1094 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1095 
1096 	/* Empty Rx FIFO */
1097 	srb_packet_count = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG) &
1098 			   KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK;
1099 	while (srb_packet_count) {
1100 		/* Drop current packet in FIFO */
1101 		ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_FIFO_LAST_REG);
1102 		srb_packet_count--;
1103 	}
1104 
1105 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1106 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
1107 		dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
1108 		return -EIO;
1109 	}
1110 
1111 	/* Enable the DMA */
1112 	iowrite32(KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE,
1113 		  pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1114 
1115 	return 0;
1116 }
1117 
1118 static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
1119 {
1120 	u32 sysid, srb_status, build;
1121 	u8 sysid_nr_chan;
1122 	int ret;
1123 
1124 	ret = kvaser_pciefd_read_cfg(pcie);
1125 	if (ret)
1126 		return ret;
1127 
1128 	sysid = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_VERSION_REG);
1129 	sysid_nr_chan = (sysid >> KVASER_PCIEFD_SYSID_NRCHAN_SHIFT) & 0xff;
1130 	if (pcie->nr_channels != sysid_nr_chan) {
1131 		dev_err(&pcie->pci->dev,
1132 			"Number of channels does not match: %u vs %u\n",
1133 			pcie->nr_channels,
1134 			sysid_nr_chan);
1135 		return -ENODEV;
1136 	}
1137 
1138 	if (pcie->nr_channels > KVASER_PCIEFD_MAX_CAN_CHANNELS)
1139 		pcie->nr_channels = KVASER_PCIEFD_MAX_CAN_CHANNELS;
1140 
1141 	build = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_BUILD_REG);
1142 	dev_dbg(&pcie->pci->dev, "Version %u.%u.%u\n",
1143 		(sysid >> KVASER_PCIEFD_SYSID_MAJOR_VER_SHIFT) & 0xff,
1144 		sysid & 0xff,
1145 		(build >> KVASER_PCIEFD_SYSID_BUILD_VER_SHIFT) & 0x7fff);
1146 
1147 	srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
1148 	if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DMA)) {
1149 		dev_err(&pcie->pci->dev,
1150 			"Hardware without DMA is not supported\n");
1151 		return -ENODEV;
1152 	}
1153 
1154 	pcie->bus_freq = ioread32(pcie->reg_base +
1155 				  KVASER_PCIEFD_SYSID_BUSFREQ_REG);
1156 	pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
1157 	pcie->freq_to_ticks_div = pcie->freq / 1000000;
1158 	if (pcie->freq_to_ticks_div == 0)
1159 		pcie->freq_to_ticks_div = 1;
1160 
1161 	/* Turn off all loopback functionality */
1162 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_LOOP_REG);
1163 	return ret;
1164 }
1165 
1166 static int kvaser_pciefd_handle_data_packet(struct kvaser_pciefd *pcie,
1167 					    struct kvaser_pciefd_rx_packet *p,
1168 					    __le32 *data)
1169 {
1170 	struct sk_buff *skb;
1171 	struct canfd_frame *cf;
1172 	struct can_priv *priv;
1173 	struct net_device_stats *stats;
1174 	struct skb_shared_hwtstamps *shhwtstamps;
1175 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1176 
1177 	if (ch_id >= pcie->nr_channels)
1178 		return -EIO;
1179 
1180 	priv = &pcie->can[ch_id]->can;
1181 	stats = &priv->dev->stats;
1182 
1183 	if (p->header[1] & KVASER_PCIEFD_RPACKET_FDF) {
1184 		skb = alloc_canfd_skb(priv->dev, &cf);
1185 		if (!skb) {
1186 			stats->rx_dropped++;
1187 			return -ENOMEM;
1188 		}
1189 
1190 		if (p->header[1] & KVASER_PCIEFD_RPACKET_BRS)
1191 			cf->flags |= CANFD_BRS;
1192 
1193 		if (p->header[1] & KVASER_PCIEFD_RPACKET_ESI)
1194 			cf->flags |= CANFD_ESI;
1195 	} else {
1196 		skb = alloc_can_skb(priv->dev, (struct can_frame **)&cf);
1197 		if (!skb) {
1198 			stats->rx_dropped++;
1199 			return -ENOMEM;
1200 		}
1201 	}
1202 
1203 	cf->can_id = p->header[0] & CAN_EFF_MASK;
1204 	if (p->header[0] & KVASER_PCIEFD_RPACKET_IDE)
1205 		cf->can_id |= CAN_EFF_FLAG;
1206 
1207 	cf->len = can_fd_dlc2len(p->header[1] >> KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1208 
1209 	if (p->header[0] & KVASER_PCIEFD_RPACKET_RTR) {
1210 		cf->can_id |= CAN_RTR_FLAG;
1211 	} else {
1212 		memcpy(cf->data, data, cf->len);
1213 
1214 		stats->rx_bytes += cf->len;
1215 	}
1216 	stats->rx_packets++;
1217 
1218 	shhwtstamps = skb_hwtstamps(skb);
1219 
1220 	shhwtstamps->hwtstamp =
1221 		ns_to_ktime(div_u64(p->timestamp * 1000,
1222 				    pcie->freq_to_ticks_div));
1223 
1224 	return netif_rx(skb);
1225 }
1226 
1227 static void kvaser_pciefd_change_state(struct kvaser_pciefd_can *can,
1228 				       struct can_frame *cf,
1229 				       enum can_state new_state,
1230 				       enum can_state tx_state,
1231 				       enum can_state rx_state)
1232 {
1233 	can_change_state(can->can.dev, cf, tx_state, rx_state);
1234 
1235 	if (new_state == CAN_STATE_BUS_OFF) {
1236 		struct net_device *ndev = can->can.dev;
1237 		unsigned long irq_flags;
1238 
1239 		spin_lock_irqsave(&can->lock, irq_flags);
1240 		netif_stop_queue(can->can.dev);
1241 		spin_unlock_irqrestore(&can->lock, irq_flags);
1242 
1243 		/* Prevent CAN controller from auto recover from bus off */
1244 		if (!can->can.restart_ms) {
1245 			kvaser_pciefd_start_controller_flush(can);
1246 			can_bus_off(ndev);
1247 		}
1248 	}
1249 }
1250 
1251 static void kvaser_pciefd_packet_to_state(struct kvaser_pciefd_rx_packet *p,
1252 					  struct can_berr_counter *bec,
1253 					  enum can_state *new_state,
1254 					  enum can_state *tx_state,
1255 					  enum can_state *rx_state)
1256 {
1257 	if (p->header[0] & KVASER_PCIEFD_SPACK_BOFF ||
1258 	    p->header[0] & KVASER_PCIEFD_SPACK_IRM)
1259 		*new_state = CAN_STATE_BUS_OFF;
1260 	else if (bec->txerr >= 255 ||  bec->rxerr >= 255)
1261 		*new_state = CAN_STATE_BUS_OFF;
1262 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EPLR)
1263 		*new_state = CAN_STATE_ERROR_PASSIVE;
1264 	else if (bec->txerr >= 128 || bec->rxerr >= 128)
1265 		*new_state = CAN_STATE_ERROR_PASSIVE;
1266 	else if (p->header[1] & KVASER_PCIEFD_SPACK_EWLR)
1267 		*new_state = CAN_STATE_ERROR_WARNING;
1268 	else if (bec->txerr >= 96 || bec->rxerr >= 96)
1269 		*new_state = CAN_STATE_ERROR_WARNING;
1270 	else
1271 		*new_state = CAN_STATE_ERROR_ACTIVE;
1272 
1273 	*tx_state = bec->txerr >= bec->rxerr ? *new_state : 0;
1274 	*rx_state = bec->txerr <= bec->rxerr ? *new_state : 0;
1275 }
1276 
1277 static int kvaser_pciefd_rx_error_frame(struct kvaser_pciefd_can *can,
1278 					struct kvaser_pciefd_rx_packet *p)
1279 {
1280 	struct can_berr_counter bec;
1281 	enum can_state old_state, new_state, tx_state, rx_state;
1282 	struct net_device *ndev = can->can.dev;
1283 	struct sk_buff *skb;
1284 	struct can_frame *cf = NULL;
1285 	struct skb_shared_hwtstamps *shhwtstamps;
1286 	struct net_device_stats *stats = &ndev->stats;
1287 
1288 	old_state = can->can.state;
1289 
1290 	bec.txerr = p->header[0] & 0xff;
1291 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1292 
1293 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1294 				      &rx_state);
1295 
1296 	skb = alloc_can_err_skb(ndev, &cf);
1297 
1298 	if (new_state != old_state) {
1299 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1300 					   rx_state);
1301 
1302 		if (old_state == CAN_STATE_BUS_OFF &&
1303 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1304 		    can->can.restart_ms) {
1305 			can->can.can_stats.restarts++;
1306 			if (skb)
1307 				cf->can_id |= CAN_ERR_RESTARTED;
1308 		}
1309 	}
1310 
1311 	can->err_rep_cnt++;
1312 	can->can.can_stats.bus_error++;
1313 	if (p->header[1] & KVASER_PCIEFD_EPACK_DIR_TX)
1314 		stats->tx_errors++;
1315 	else
1316 		stats->rx_errors++;
1317 
1318 	can->bec.txerr = bec.txerr;
1319 	can->bec.rxerr = bec.rxerr;
1320 
1321 	if (!skb) {
1322 		stats->rx_dropped++;
1323 		return -ENOMEM;
1324 	}
1325 
1326 	shhwtstamps = skb_hwtstamps(skb);
1327 	shhwtstamps->hwtstamp =
1328 		ns_to_ktime(div_u64(p->timestamp * 1000,
1329 				    can->kv_pcie->freq_to_ticks_div));
1330 	cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT;
1331 
1332 	cf->data[6] = bec.txerr;
1333 	cf->data[7] = bec.rxerr;
1334 
1335 	netif_rx(skb);
1336 	return 0;
1337 }
1338 
1339 static int kvaser_pciefd_handle_error_packet(struct kvaser_pciefd *pcie,
1340 					     struct kvaser_pciefd_rx_packet *p)
1341 {
1342 	struct kvaser_pciefd_can *can;
1343 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1344 
1345 	if (ch_id >= pcie->nr_channels)
1346 		return -EIO;
1347 
1348 	can = pcie->can[ch_id];
1349 
1350 	kvaser_pciefd_rx_error_frame(can, p);
1351 	if (can->err_rep_cnt >= KVASER_PCIEFD_MAX_ERR_REP)
1352 		/* Do not report more errors, until bec_poll_timer expires */
1353 		kvaser_pciefd_disable_err_gen(can);
1354 	/* Start polling the error counters */
1355 	mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1356 	return 0;
1357 }
1358 
1359 static int kvaser_pciefd_handle_status_resp(struct kvaser_pciefd_can *can,
1360 					    struct kvaser_pciefd_rx_packet *p)
1361 {
1362 	struct can_berr_counter bec;
1363 	enum can_state old_state, new_state, tx_state, rx_state;
1364 
1365 	old_state = can->can.state;
1366 
1367 	bec.txerr = p->header[0] & 0xff;
1368 	bec.rxerr = (p->header[0] >> KVASER_PCIEFD_SPACK_RXERR_SHIFT) & 0xff;
1369 
1370 	kvaser_pciefd_packet_to_state(p, &bec, &new_state, &tx_state,
1371 				      &rx_state);
1372 
1373 	if (new_state != old_state) {
1374 		struct net_device *ndev = can->can.dev;
1375 		struct sk_buff *skb;
1376 		struct can_frame *cf;
1377 		struct skb_shared_hwtstamps *shhwtstamps;
1378 
1379 		skb = alloc_can_err_skb(ndev, &cf);
1380 		if (!skb) {
1381 			struct net_device_stats *stats = &ndev->stats;
1382 
1383 			stats->rx_dropped++;
1384 			return -ENOMEM;
1385 		}
1386 
1387 		kvaser_pciefd_change_state(can, cf, new_state, tx_state,
1388 					   rx_state);
1389 
1390 		if (old_state == CAN_STATE_BUS_OFF &&
1391 		    new_state == CAN_STATE_ERROR_ACTIVE &&
1392 		    can->can.restart_ms) {
1393 			can->can.can_stats.restarts++;
1394 			cf->can_id |= CAN_ERR_RESTARTED;
1395 		}
1396 
1397 		shhwtstamps = skb_hwtstamps(skb);
1398 		shhwtstamps->hwtstamp =
1399 			ns_to_ktime(div_u64(p->timestamp * 1000,
1400 					    can->kv_pcie->freq_to_ticks_div));
1401 
1402 		cf->data[6] = bec.txerr;
1403 		cf->data[7] = bec.rxerr;
1404 
1405 		netif_rx(skb);
1406 	}
1407 	can->bec.txerr = bec.txerr;
1408 	can->bec.rxerr = bec.rxerr;
1409 	/* Check if we need to poll the error counters */
1410 	if (bec.txerr || bec.rxerr)
1411 		mod_timer(&can->bec_poll_timer, KVASER_PCIEFD_BEC_POLL_FREQ);
1412 
1413 	return 0;
1414 }
1415 
1416 static int kvaser_pciefd_handle_status_packet(struct kvaser_pciefd *pcie,
1417 					      struct kvaser_pciefd_rx_packet *p)
1418 {
1419 	struct kvaser_pciefd_can *can;
1420 	u8 cmdseq;
1421 	u32 status;
1422 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1423 
1424 	if (ch_id >= pcie->nr_channels)
1425 		return -EIO;
1426 
1427 	can = pcie->can[ch_id];
1428 
1429 	status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG);
1430 	cmdseq = (status >> KVASER_PCIEFD_KCAN_STAT_SEQNO_SHIFT) & 0xff;
1431 
1432 	/* Reset done, start abort and flush */
1433 	if (p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1434 	    p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1435 	    p->header[1] & KVASER_PCIEFD_SPACK_AUTO &&
1436 	    cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1437 	    status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1438 		u32 cmd;
1439 
1440 		iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD,
1441 			  can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1442 		cmd = KVASER_PCIEFD_KCAN_CMD_AT;
1443 		cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT;
1444 		iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG);
1445 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET &&
1446 		   p->header[0] & KVASER_PCIEFD_SPACK_IRM &&
1447 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) &&
1448 		   status & KVASER_PCIEFD_KCAN_STAT_IDLE) {
1449 		/* Reset detected, send end of flush if no packet are in FIFO */
1450 		u8 count = ioread32(can->reg_base +
1451 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1452 
1453 		if (!count)
1454 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1455 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1456 	} else if (!(p->header[1] & KVASER_PCIEFD_SPACK_AUTO) &&
1457 		   cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK)) {
1458 		/* Response to status request received */
1459 		kvaser_pciefd_handle_status_resp(can, p);
1460 		if (can->can.state != CAN_STATE_BUS_OFF &&
1461 		    can->can.state != CAN_STATE_ERROR_ACTIVE) {
1462 			mod_timer(&can->bec_poll_timer,
1463 				  KVASER_PCIEFD_BEC_POLL_FREQ);
1464 		}
1465 	} else if (p->header[0] & KVASER_PCIEFD_SPACK_RMCD &&
1466 		   !(status & KVASER_PCIEFD_KCAN_STAT_BUS_OFF_MSK)) {
1467 		/* Reset to bus on detected */
1468 		if (!completion_done(&can->start_comp))
1469 			complete(&can->start_comp);
1470 	}
1471 
1472 	return 0;
1473 }
1474 
1475 static int kvaser_pciefd_handle_eack_packet(struct kvaser_pciefd *pcie,
1476 					    struct kvaser_pciefd_rx_packet *p)
1477 {
1478 	struct kvaser_pciefd_can *can;
1479 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1480 
1481 	if (ch_id >= pcie->nr_channels)
1482 		return -EIO;
1483 
1484 	can = pcie->can[ch_id];
1485 
1486 	/* If this is the last flushed packet, send end of flush */
1487 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1488 		u8 count = ioread32(can->reg_base +
1489 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1490 
1491 		if (count == 0)
1492 			iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH,
1493 				  can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG);
1494 	} else {
1495 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1496 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1497 		struct net_device_stats *stats = &can->can.dev->stats;
1498 
1499 		stats->tx_bytes += dlc;
1500 		stats->tx_packets++;
1501 
1502 		if (netif_queue_stopped(can->can.dev))
1503 			netif_wake_queue(can->can.dev);
1504 	}
1505 
1506 	return 0;
1507 }
1508 
1509 static void kvaser_pciefd_handle_nack_packet(struct kvaser_pciefd_can *can,
1510 					     struct kvaser_pciefd_rx_packet *p)
1511 {
1512 	struct sk_buff *skb;
1513 	struct net_device_stats *stats = &can->can.dev->stats;
1514 	struct can_frame *cf;
1515 
1516 	skb = alloc_can_err_skb(can->can.dev, &cf);
1517 
1518 	stats->tx_errors++;
1519 	if (p->header[0] & KVASER_PCIEFD_APACKET_ABL) {
1520 		if (skb)
1521 			cf->can_id |= CAN_ERR_LOSTARB;
1522 		can->can.can_stats.arbitration_lost++;
1523 	} else if (skb) {
1524 		cf->can_id |= CAN_ERR_ACK;
1525 	}
1526 
1527 	if (skb) {
1528 		cf->can_id |= CAN_ERR_BUSERROR;
1529 		netif_rx(skb);
1530 	} else {
1531 		stats->rx_dropped++;
1532 		netdev_warn(can->can.dev, "No memory left for err_skb\n");
1533 	}
1534 }
1535 
1536 static int kvaser_pciefd_handle_ack_packet(struct kvaser_pciefd *pcie,
1537 					   struct kvaser_pciefd_rx_packet *p)
1538 {
1539 	struct kvaser_pciefd_can *can;
1540 	bool one_shot_fail = false;
1541 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1542 
1543 	if (ch_id >= pcie->nr_channels)
1544 		return -EIO;
1545 
1546 	can = pcie->can[ch_id];
1547 	/* Ignore control packet ACK */
1548 	if (p->header[0] & KVASER_PCIEFD_APACKET_CT)
1549 		return 0;
1550 
1551 	if (p->header[0] & KVASER_PCIEFD_APACKET_NACK) {
1552 		kvaser_pciefd_handle_nack_packet(can, p);
1553 		one_shot_fail = true;
1554 	}
1555 
1556 	if (p->header[0] & KVASER_PCIEFD_APACKET_FLU) {
1557 		netdev_dbg(can->can.dev, "Packet was flushed\n");
1558 	} else {
1559 		int echo_idx = p->header[0] & KVASER_PCIEFD_PACKET_SEQ_MSK;
1560 		int dlc = can_get_echo_skb(can->can.dev, echo_idx, NULL);
1561 		u8 count = ioread32(can->reg_base +
1562 				    KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff;
1563 
1564 		if (count < KVASER_PCIEFD_CAN_TX_MAX_COUNT &&
1565 		    netif_queue_stopped(can->can.dev))
1566 			netif_wake_queue(can->can.dev);
1567 
1568 		if (!one_shot_fail) {
1569 			struct net_device_stats *stats = &can->can.dev->stats;
1570 
1571 			stats->tx_bytes += dlc;
1572 			stats->tx_packets++;
1573 		}
1574 	}
1575 
1576 	return 0;
1577 }
1578 
1579 static int kvaser_pciefd_handle_eflush_packet(struct kvaser_pciefd *pcie,
1580 					      struct kvaser_pciefd_rx_packet *p)
1581 {
1582 	struct kvaser_pciefd_can *can;
1583 	u8 ch_id = (p->header[1] >> KVASER_PCIEFD_PACKET_CHID_SHIFT) & 0x7;
1584 
1585 	if (ch_id >= pcie->nr_channels)
1586 		return -EIO;
1587 
1588 	can = pcie->can[ch_id];
1589 
1590 	if (!completion_done(&can->flush_comp))
1591 		complete(&can->flush_comp);
1592 
1593 	return 0;
1594 }
1595 
1596 static int kvaser_pciefd_read_packet(struct kvaser_pciefd *pcie, int *start_pos,
1597 				     int dma_buf)
1598 {
1599 	__le32 *buffer = pcie->dma_data[dma_buf];
1600 	__le64 timestamp;
1601 	struct kvaser_pciefd_rx_packet packet;
1602 	struct kvaser_pciefd_rx_packet *p = &packet;
1603 	u8 type;
1604 	int pos = *start_pos;
1605 	int size;
1606 	int ret = 0;
1607 
1608 	size = le32_to_cpu(buffer[pos++]);
1609 	if (!size) {
1610 		*start_pos = 0;
1611 		return 0;
1612 	}
1613 
1614 	p->header[0] = le32_to_cpu(buffer[pos++]);
1615 	p->header[1] = le32_to_cpu(buffer[pos++]);
1616 
1617 	/* Read 64-bit timestamp */
1618 	memcpy(&timestamp, &buffer[pos], sizeof(__le64));
1619 	pos += 2;
1620 	p->timestamp = le64_to_cpu(timestamp);
1621 
1622 	type = (p->header[1] >> KVASER_PCIEFD_PACKET_TYPE_SHIFT) & 0xf;
1623 	switch (type) {
1624 	case KVASER_PCIEFD_PACK_TYPE_DATA:
1625 		ret = kvaser_pciefd_handle_data_packet(pcie, p, &buffer[pos]);
1626 		if (!(p->header[0] & KVASER_PCIEFD_RPACKET_RTR)) {
1627 			u8 data_len;
1628 
1629 			data_len = can_fd_dlc2len(p->header[1] >>
1630 					       KVASER_PCIEFD_RPACKET_DLC_SHIFT);
1631 			pos += DIV_ROUND_UP(data_len, 4);
1632 		}
1633 		break;
1634 
1635 	case KVASER_PCIEFD_PACK_TYPE_ACK:
1636 		ret = kvaser_pciefd_handle_ack_packet(pcie, p);
1637 		break;
1638 
1639 	case KVASER_PCIEFD_PACK_TYPE_STATUS:
1640 		ret = kvaser_pciefd_handle_status_packet(pcie, p);
1641 		break;
1642 
1643 	case KVASER_PCIEFD_PACK_TYPE_ERROR:
1644 		ret = kvaser_pciefd_handle_error_packet(pcie, p);
1645 		break;
1646 
1647 	case KVASER_PCIEFD_PACK_TYPE_EFRAME_ACK:
1648 		ret = kvaser_pciefd_handle_eack_packet(pcie, p);
1649 		break;
1650 
1651 	case KVASER_PCIEFD_PACK_TYPE_EFLUSH_ACK:
1652 		ret = kvaser_pciefd_handle_eflush_packet(pcie, p);
1653 		break;
1654 
1655 	case KVASER_PCIEFD_PACK_TYPE_ACK_DATA:
1656 	case KVASER_PCIEFD_PACK_TYPE_BUS_LOAD:
1657 	case KVASER_PCIEFD_PACK_TYPE_TXRQ:
1658 		dev_info(&pcie->pci->dev,
1659 			 "Received unexpected packet type 0x%08X\n", type);
1660 		break;
1661 
1662 	default:
1663 		dev_err(&pcie->pci->dev, "Unknown packet type 0x%08X\n", type);
1664 		ret = -EIO;
1665 		break;
1666 	}
1667 
1668 	if (ret)
1669 		return ret;
1670 
1671 	/* Position does not point to the end of the package,
1672 	 * corrupted packet size?
1673 	 */
1674 	if ((*start_pos + size) != pos)
1675 		return -EIO;
1676 
1677 	/* Point to the next packet header, if any */
1678 	*start_pos = pos;
1679 
1680 	return ret;
1681 }
1682 
1683 static int kvaser_pciefd_read_buffer(struct kvaser_pciefd *pcie, int dma_buf)
1684 {
1685 	int pos = 0;
1686 	int res = 0;
1687 
1688 	do {
1689 		res = kvaser_pciefd_read_packet(pcie, &pos, dma_buf);
1690 	} while (!res && pos > 0 && pos < KVASER_PCIEFD_DMA_SIZE);
1691 
1692 	return res;
1693 }
1694 
1695 static int kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
1696 {
1697 	u32 irq;
1698 
1699 	irq = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1700 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
1701 		kvaser_pciefd_read_buffer(pcie, 0);
1702 		/* Reset DMA buffer 0 */
1703 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1704 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1705 	}
1706 
1707 	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
1708 		kvaser_pciefd_read_buffer(pcie, 1);
1709 		/* Reset DMA buffer 1 */
1710 		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1711 			  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1712 	}
1713 
1714 	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
1715 	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
1716 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
1717 	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
1718 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
1719 
1720 	iowrite32(irq, pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1721 	return 0;
1722 }
1723 
1724 static int kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
1725 {
1726 	u32 irq = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1727 
1728 	if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF)
1729 		netdev_err(can->can.dev, "Tx FIFO overflow\n");
1730 
1731 	if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP)
1732 		netdev_err(can->can.dev,
1733 			   "Fail to change bittiming, when not in reset mode\n");
1734 
1735 	if (irq & KVASER_PCIEFD_KCAN_IRQ_FDIC)
1736 		netdev_err(can->can.dev, "CAN FD frame in CAN mode\n");
1737 
1738 	if (irq & KVASER_PCIEFD_KCAN_IRQ_ROF)
1739 		netdev_err(can->can.dev, "Rx FIFO overflow\n");
1740 
1741 	iowrite32(irq, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG);
1742 	return 0;
1743 }
1744 
1745 static irqreturn_t kvaser_pciefd_irq_handler(int irq, void *dev)
1746 {
1747 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
1748 	u32 board_irq;
1749 	int i;
1750 
1751 	board_irq = ioread32(pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1752 
1753 	if (!(board_irq & KVASER_PCIEFD_IRQ_ALL_MSK))
1754 		return IRQ_NONE;
1755 
1756 	if (board_irq & KVASER_PCIEFD_IRQ_SRB)
1757 		kvaser_pciefd_receive_irq(pcie);
1758 
1759 	for (i = 0; i < pcie->nr_channels; i++) {
1760 		if (!pcie->can[i]) {
1761 			dev_err(&pcie->pci->dev,
1762 				"IRQ mask points to unallocated controller\n");
1763 			break;
1764 		}
1765 
1766 		/* Check that mask matches channel (i) IRQ mask */
1767 		if (board_irq & (1 << i))
1768 			kvaser_pciefd_transmit_irq(pcie->can[i]);
1769 	}
1770 
1771 	iowrite32(board_irq, pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1772 	return IRQ_HANDLED;
1773 }
1774 
1775 static void kvaser_pciefd_teardown_can_ctrls(struct kvaser_pciefd *pcie)
1776 {
1777 	int i;
1778 	struct kvaser_pciefd_can *can;
1779 
1780 	for (i = 0; i < pcie->nr_channels; i++) {
1781 		can = pcie->can[i];
1782 		if (can) {
1783 			iowrite32(0,
1784 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1785 			kvaser_pciefd_pwm_stop(can);
1786 			free_candev(can->can.dev);
1787 		}
1788 	}
1789 }
1790 
1791 static int kvaser_pciefd_probe(struct pci_dev *pdev,
1792 			       const struct pci_device_id *id)
1793 {
1794 	int err;
1795 	struct kvaser_pciefd *pcie;
1796 
1797 	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
1798 	if (!pcie)
1799 		return -ENOMEM;
1800 
1801 	pci_set_drvdata(pdev, pcie);
1802 	pcie->pci = pdev;
1803 
1804 	err = pci_enable_device(pdev);
1805 	if (err)
1806 		return err;
1807 
1808 	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
1809 	if (err)
1810 		goto err_disable_pci;
1811 
1812 	pcie->reg_base = pci_iomap(pdev, 0, 0);
1813 	if (!pcie->reg_base) {
1814 		err = -ENOMEM;
1815 		goto err_release_regions;
1816 	}
1817 
1818 	err = kvaser_pciefd_setup_board(pcie);
1819 	if (err)
1820 		goto err_pci_iounmap;
1821 
1822 	err = kvaser_pciefd_setup_dma(pcie);
1823 	if (err)
1824 		goto err_pci_iounmap;
1825 
1826 	pci_set_master(pdev);
1827 
1828 	err = kvaser_pciefd_setup_can_ctrls(pcie);
1829 	if (err)
1830 		goto err_teardown_can_ctrls;
1831 
1832 	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
1833 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
1834 	if (err)
1835 		goto err_teardown_can_ctrls;
1836 
1837 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
1838 		  pcie->reg_base + KVASER_PCIEFD_SRB_IRQ_REG);
1839 
1840 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1 |
1841 		  KVASER_PCIEFD_SRB_IRQ_DOF0 | KVASER_PCIEFD_SRB_IRQ_DOF1 |
1842 		  KVASER_PCIEFD_SRB_IRQ_DUF0 | KVASER_PCIEFD_SRB_IRQ_DUF1,
1843 		  pcie->reg_base + KVASER_PCIEFD_SRB_IEN_REG);
1844 
1845 	/* Reset IRQ handling, expected to be off before */
1846 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1847 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1848 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1849 		  pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1850 
1851 	/* Ready the DMA buffers */
1852 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
1853 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1854 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
1855 		  pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
1856 
1857 	err = kvaser_pciefd_reg_candev(pcie);
1858 	if (err)
1859 		goto err_free_irq;
1860 
1861 	return 0;
1862 
1863 err_free_irq:
1864 	/* Disable PCI interrupts */
1865 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1866 	free_irq(pcie->pci->irq, pcie);
1867 
1868 err_teardown_can_ctrls:
1869 	kvaser_pciefd_teardown_can_ctrls(pcie);
1870 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1871 	pci_clear_master(pdev);
1872 
1873 err_pci_iounmap:
1874 	pci_iounmap(pdev, pcie->reg_base);
1875 
1876 err_release_regions:
1877 	pci_release_regions(pdev);
1878 
1879 err_disable_pci:
1880 	pci_disable_device(pdev);
1881 
1882 	return err;
1883 }
1884 
1885 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
1886 {
1887 	struct kvaser_pciefd_can *can;
1888 	int i;
1889 
1890 	for (i = 0; i < pcie->nr_channels; i++) {
1891 		can = pcie->can[i];
1892 		if (can) {
1893 			iowrite32(0,
1894 				  can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
1895 			unregister_candev(can->can.dev);
1896 			del_timer(&can->bec_poll_timer);
1897 			kvaser_pciefd_pwm_stop(can);
1898 			free_candev(can->can.dev);
1899 		}
1900 	}
1901 }
1902 
1903 static void kvaser_pciefd_remove(struct pci_dev *pdev)
1904 {
1905 	struct kvaser_pciefd *pcie = pci_get_drvdata(pdev);
1906 
1907 	kvaser_pciefd_remove_all_ctrls(pcie);
1908 
1909 	/* Turn off IRQ generation */
1910 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_SRB_CTRL_REG);
1911 	iowrite32(KVASER_PCIEFD_IRQ_ALL_MSK,
1912 		  pcie->reg_base + KVASER_PCIEFD_IRQ_REG);
1913 	iowrite32(0, pcie->reg_base + KVASER_PCIEFD_IEN_REG);
1914 
1915 	free_irq(pcie->pci->irq, pcie);
1916 
1917 	pci_iounmap(pdev, pcie->reg_base);
1918 	pci_release_regions(pdev);
1919 	pci_disable_device(pdev);
1920 }
1921 
1922 static struct pci_driver kvaser_pciefd = {
1923 	.name = KVASER_PCIEFD_DRV_NAME,
1924 	.id_table = kvaser_pciefd_id_table,
1925 	.probe = kvaser_pciefd_probe,
1926 	.remove = kvaser_pciefd_remove,
1927 };
1928 
1929 module_pci_driver(kvaser_pciefd)
1930