xref: /linux/drivers/ntb/hw/mscc/ntb_hw_switchtec.c (revision 6619bf954984e625f5ba46e810ed08054309efab)
1 /*
2  * Microsemi Switchtec(tm) PCIe Management Driver
3  * Copyright (c) 2017, Microsemi Corporation
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  */
15 
16 #include <linux/switchtec.h>
17 #include <linux/module.h>
18 #include <linux/delay.h>
19 #include <linux/kthread.h>
20 #include <linux/interrupt.h>
21 #include <linux/ntb.h>
22 
23 MODULE_DESCRIPTION("Microsemi Switchtec(tm) NTB Driver");
24 MODULE_VERSION("0.1");
25 MODULE_LICENSE("GPL");
26 MODULE_AUTHOR("Microsemi Corporation");
27 
28 static bool use_lut_mws;
29 module_param(use_lut_mws, bool, 0644);
30 MODULE_PARM_DESC(use_lut_mws,
31 		 "Enable the use of the LUT based memory windows");
32 
33 #ifndef ioread64
34 #ifdef readq
35 #define ioread64 readq
36 #else
37 #define ioread64 _ioread64
38 static inline u64 _ioread64(void __iomem *mmio)
39 {
40 	u64 low, high;
41 
42 	low = ioread32(mmio);
43 	high = ioread32(mmio + sizeof(u32));
44 	return low | (high << 32);
45 }
46 #endif
47 #endif
48 
49 #ifndef iowrite64
50 #ifdef writeq
51 #define iowrite64 writeq
52 #else
53 #define iowrite64 _iowrite64
54 static inline void _iowrite64(u64 val, void __iomem *mmio)
55 {
56 	iowrite32(val, mmio);
57 	iowrite32(val >> 32, mmio + sizeof(u32));
58 }
59 #endif
60 #endif
61 
62 #define SWITCHTEC_NTB_MAGIC 0x45CC0001
63 #define MAX_MWS     128
64 
65 struct shared_mw {
66 	u32 magic;
67 	u32 link_sta;
68 	u32 partition_id;
69 	u64 mw_sizes[MAX_MWS];
70 };
71 
72 #define MAX_DIRECT_MW ARRAY_SIZE(((struct ntb_ctrl_regs *)(0))->bar_entry)
73 #define LUT_SIZE SZ_64K
74 
75 struct switchtec_ntb {
76 	struct ntb_dev ntb;
77 	struct switchtec_dev *stdev;
78 
79 	int self_partition;
80 	int peer_partition;
81 
82 	int doorbell_irq;
83 	int message_irq;
84 
85 	struct ntb_info_regs __iomem *mmio_ntb;
86 	struct ntb_ctrl_regs __iomem *mmio_ctrl;
87 	struct ntb_dbmsg_regs __iomem *mmio_dbmsg;
88 	struct ntb_ctrl_regs __iomem *mmio_self_ctrl;
89 	struct ntb_ctrl_regs __iomem *mmio_peer_ctrl;
90 	struct ntb_dbmsg_regs __iomem *mmio_self_dbmsg;
91 
92 	struct shared_mw *self_shared;
93 	struct shared_mw __iomem *peer_shared;
94 	dma_addr_t self_shared_dma;
95 
96 	u64 db_mask;
97 	u64 db_valid_mask;
98 	int db_shift;
99 	int db_peer_shift;
100 
101 	/* synchronize rmw access of db_mask and hw reg */
102 	spinlock_t db_mask_lock;
103 
104 	int nr_direct_mw;
105 	int nr_lut_mw;
106 	int direct_mw_to_bar[MAX_DIRECT_MW];
107 
108 	int peer_nr_direct_mw;
109 	int peer_nr_lut_mw;
110 	int peer_direct_mw_to_bar[MAX_DIRECT_MW];
111 
112 	bool link_is_up;
113 	enum ntb_speed link_speed;
114 	enum ntb_width link_width;
115 };
116 
117 static struct switchtec_ntb *ntb_sndev(struct ntb_dev *ntb)
118 {
119 	return container_of(ntb, struct switchtec_ntb, ntb);
120 }
121 
122 static int switchtec_ntb_part_op(struct switchtec_ntb *sndev,
123 				 struct ntb_ctrl_regs __iomem *ctl,
124 				 u32 op, int wait_status)
125 {
126 	static const char * const op_text[] = {
127 		[NTB_CTRL_PART_OP_LOCK] = "lock",
128 		[NTB_CTRL_PART_OP_CFG] = "configure",
129 		[NTB_CTRL_PART_OP_RESET] = "reset",
130 	};
131 
132 	int i;
133 	u32 ps;
134 	int status;
135 
136 	switch (op) {
137 	case NTB_CTRL_PART_OP_LOCK:
138 		status = NTB_CTRL_PART_STATUS_LOCKING;
139 		break;
140 	case NTB_CTRL_PART_OP_CFG:
141 		status = NTB_CTRL_PART_STATUS_CONFIGURING;
142 		break;
143 	case NTB_CTRL_PART_OP_RESET:
144 		status = NTB_CTRL_PART_STATUS_RESETTING;
145 		break;
146 	default:
147 		return -EINVAL;
148 	}
149 
150 	iowrite32(op, &ctl->partition_op);
151 
152 	for (i = 0; i < 1000; i++) {
153 		if (msleep_interruptible(50) != 0) {
154 			iowrite32(NTB_CTRL_PART_OP_RESET, &ctl->partition_op);
155 			return -EINTR;
156 		}
157 
158 		ps = ioread32(&ctl->partition_status) & 0xFFFF;
159 
160 		if (ps != status)
161 			break;
162 	}
163 
164 	if (ps == wait_status)
165 		return 0;
166 
167 	if (ps == status) {
168 		dev_err(&sndev->stdev->dev,
169 			"Timed out while peforming %s (%d). (%08x)",
170 			op_text[op], op,
171 			ioread32(&ctl->partition_status));
172 
173 		return -ETIMEDOUT;
174 	}
175 
176 	return -EIO;
177 }
178 
179 static int switchtec_ntb_send_msg(struct switchtec_ntb *sndev, int idx,
180 				  u32 val)
181 {
182 	if (idx < 0 || idx >= ARRAY_SIZE(sndev->mmio_self_dbmsg->omsg))
183 		return -EINVAL;
184 
185 	iowrite32(val, &sndev->mmio_self_dbmsg->omsg[idx].msg);
186 
187 	return 0;
188 }
189 
190 static int switchtec_ntb_mw_count(struct ntb_dev *ntb, int pidx)
191 {
192 	return 0;
193 }
194 
195 static int switchtec_ntb_mw_get_align(struct ntb_dev *ntb, int pidx,
196 				      int widx, resource_size_t *addr_align,
197 				      resource_size_t *size_align,
198 				      resource_size_t *size_max)
199 {
200 	return 0;
201 }
202 
203 static int switchtec_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx,
204 				      dma_addr_t addr, resource_size_t size)
205 {
206 	return 0;
207 }
208 
209 static int switchtec_ntb_peer_mw_count(struct ntb_dev *ntb)
210 {
211 	return 0;
212 }
213 
214 static int switchtec_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
215 					  phys_addr_t *base,
216 					  resource_size_t *size)
217 {
218 	return 0;
219 }
220 
221 static void switchtec_ntb_part_link_speed(struct switchtec_ntb *sndev,
222 					  int partition,
223 					  enum ntb_speed *speed,
224 					  enum ntb_width *width)
225 {
226 	struct switchtec_dev *stdev = sndev->stdev;
227 
228 	u32 pff = ioread32(&stdev->mmio_part_cfg[partition].vep_pff_inst_id);
229 	u32 linksta = ioread32(&stdev->mmio_pff_csr[pff].pci_cap_region[13]);
230 
231 	if (speed)
232 		*speed = (linksta >> 16) & 0xF;
233 
234 	if (width)
235 		*width = (linksta >> 20) & 0x3F;
236 }
237 
238 static void switchtec_ntb_set_link_speed(struct switchtec_ntb *sndev)
239 {
240 	enum ntb_speed self_speed, peer_speed;
241 	enum ntb_width self_width, peer_width;
242 
243 	if (!sndev->link_is_up) {
244 		sndev->link_speed = NTB_SPEED_NONE;
245 		sndev->link_width = NTB_WIDTH_NONE;
246 		return;
247 	}
248 
249 	switchtec_ntb_part_link_speed(sndev, sndev->self_partition,
250 				      &self_speed, &self_width);
251 	switchtec_ntb_part_link_speed(sndev, sndev->peer_partition,
252 				      &peer_speed, &peer_width);
253 
254 	sndev->link_speed = min(self_speed, peer_speed);
255 	sndev->link_width = min(self_width, peer_width);
256 }
257 
258 enum {
259 	LINK_MESSAGE = 0,
260 	MSG_LINK_UP = 1,
261 	MSG_LINK_DOWN = 2,
262 	MSG_CHECK_LINK = 3,
263 };
264 
265 static void switchtec_ntb_check_link(struct switchtec_ntb *sndev)
266 {
267 	int link_sta;
268 	int old = sndev->link_is_up;
269 
270 	link_sta = sndev->self_shared->link_sta;
271 	if (link_sta) {
272 		u64 peer = ioread64(&sndev->peer_shared->magic);
273 
274 		if ((peer & 0xFFFFFFFF) == SWITCHTEC_NTB_MAGIC)
275 			link_sta = peer >> 32;
276 		else
277 			link_sta = 0;
278 	}
279 
280 	sndev->link_is_up = link_sta;
281 	switchtec_ntb_set_link_speed(sndev);
282 
283 	if (link_sta != old) {
284 		switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_CHECK_LINK);
285 		ntb_link_event(&sndev->ntb);
286 		dev_info(&sndev->stdev->dev, "ntb link %s",
287 			 link_sta ? "up" : "down");
288 	}
289 }
290 
291 static void switchtec_ntb_link_notification(struct switchtec_dev *stdev)
292 {
293 	struct switchtec_ntb *sndev = stdev->sndev;
294 
295 	switchtec_ntb_check_link(sndev);
296 }
297 
298 static u64 switchtec_ntb_link_is_up(struct ntb_dev *ntb,
299 				    enum ntb_speed *speed,
300 				    enum ntb_width *width)
301 {
302 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
303 
304 	if (speed)
305 		*speed = sndev->link_speed;
306 	if (width)
307 		*width = sndev->link_width;
308 
309 	return sndev->link_is_up;
310 }
311 
312 static int switchtec_ntb_link_enable(struct ntb_dev *ntb,
313 				     enum ntb_speed max_speed,
314 				     enum ntb_width max_width)
315 {
316 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
317 
318 	dev_dbg(&sndev->stdev->dev, "enabling link");
319 
320 	sndev->self_shared->link_sta = 1;
321 	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_UP);
322 
323 	switchtec_ntb_check_link(sndev);
324 
325 	return 0;
326 }
327 
328 static int switchtec_ntb_link_disable(struct ntb_dev *ntb)
329 {
330 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
331 
332 	dev_dbg(&sndev->stdev->dev, "disabling link");
333 
334 	sndev->self_shared->link_sta = 0;
335 	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_UP);
336 
337 	switchtec_ntb_check_link(sndev);
338 
339 	return 0;
340 }
341 
342 static u64 switchtec_ntb_db_valid_mask(struct ntb_dev *ntb)
343 {
344 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
345 
346 	return sndev->db_valid_mask;
347 }
348 
349 static int switchtec_ntb_db_vector_count(struct ntb_dev *ntb)
350 {
351 	return 1;
352 }
353 
354 static u64 switchtec_ntb_db_vector_mask(struct ntb_dev *ntb, int db_vector)
355 {
356 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
357 
358 	if (db_vector < 0 || db_vector > 1)
359 		return 0;
360 
361 	return sndev->db_valid_mask;
362 }
363 
364 static u64 switchtec_ntb_db_read(struct ntb_dev *ntb)
365 {
366 	u64 ret;
367 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
368 
369 	ret = ioread64(&sndev->mmio_self_dbmsg->idb) >> sndev->db_shift;
370 
371 	return ret & sndev->db_valid_mask;
372 }
373 
374 static int switchtec_ntb_db_clear(struct ntb_dev *ntb, u64 db_bits)
375 {
376 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
377 
378 	iowrite64(db_bits << sndev->db_shift, &sndev->mmio_self_dbmsg->idb);
379 
380 	return 0;
381 }
382 
383 static int switchtec_ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
384 {
385 	unsigned long irqflags;
386 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
387 
388 	if (db_bits & ~sndev->db_valid_mask)
389 		return -EINVAL;
390 
391 	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
392 
393 	sndev->db_mask |= db_bits << sndev->db_shift;
394 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
395 
396 	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
397 
398 	return 0;
399 }
400 
401 static int switchtec_ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
402 {
403 	unsigned long irqflags;
404 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
405 
406 	if (db_bits & ~sndev->db_valid_mask)
407 		return -EINVAL;
408 
409 	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
410 
411 	sndev->db_mask &= ~(db_bits << sndev->db_shift);
412 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
413 
414 	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
415 
416 	return 0;
417 }
418 
419 static u64 switchtec_ntb_db_read_mask(struct ntb_dev *ntb)
420 {
421 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
422 
423 	return (sndev->db_mask >> sndev->db_shift) & sndev->db_valid_mask;
424 }
425 
426 static int switchtec_ntb_peer_db_addr(struct ntb_dev *ntb,
427 				      phys_addr_t *db_addr,
428 				      resource_size_t *db_size)
429 {
430 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
431 	unsigned long offset;
432 
433 	offset = (unsigned long)sndev->mmio_self_dbmsg->odb -
434 		(unsigned long)sndev->stdev->mmio;
435 
436 	offset += sndev->db_shift / 8;
437 
438 	if (db_addr)
439 		*db_addr = pci_resource_start(ntb->pdev, 0) + offset;
440 	if (db_size)
441 		*db_size = sizeof(u32);
442 
443 	return 0;
444 }
445 
446 static int switchtec_ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
447 {
448 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
449 
450 	iowrite64(db_bits << sndev->db_peer_shift,
451 		  &sndev->mmio_self_dbmsg->odb);
452 
453 	return 0;
454 }
455 
456 static int switchtec_ntb_spad_count(struct ntb_dev *ntb)
457 {
458 	return 0;
459 }
460 
461 static u32 switchtec_ntb_spad_read(struct ntb_dev *ntb, int idx)
462 {
463 	return 0;
464 }
465 
466 static int switchtec_ntb_spad_write(struct ntb_dev *ntb, int idx, u32 val)
467 {
468 	return 0;
469 }
470 
471 static int switchtec_ntb_peer_spad_write(struct ntb_dev *ntb, int pidx,
472 					 int sidx, u32 val)
473 {
474 	return 0;
475 }
476 
477 static const struct ntb_dev_ops switchtec_ntb_ops = {
478 	.mw_count		= switchtec_ntb_mw_count,
479 	.mw_get_align		= switchtec_ntb_mw_get_align,
480 	.mw_set_trans		= switchtec_ntb_mw_set_trans,
481 	.peer_mw_count		= switchtec_ntb_peer_mw_count,
482 	.peer_mw_get_addr	= switchtec_ntb_peer_mw_get_addr,
483 	.link_is_up		= switchtec_ntb_link_is_up,
484 	.link_enable		= switchtec_ntb_link_enable,
485 	.link_disable		= switchtec_ntb_link_disable,
486 	.db_valid_mask		= switchtec_ntb_db_valid_mask,
487 	.db_vector_count	= switchtec_ntb_db_vector_count,
488 	.db_vector_mask		= switchtec_ntb_db_vector_mask,
489 	.db_read		= switchtec_ntb_db_read,
490 	.db_clear		= switchtec_ntb_db_clear,
491 	.db_set_mask		= switchtec_ntb_db_set_mask,
492 	.db_clear_mask		= switchtec_ntb_db_clear_mask,
493 	.db_read_mask		= switchtec_ntb_db_read_mask,
494 	.peer_db_addr		= switchtec_ntb_peer_db_addr,
495 	.peer_db_set		= switchtec_ntb_peer_db_set,
496 	.spad_count		= switchtec_ntb_spad_count,
497 	.spad_read		= switchtec_ntb_spad_read,
498 	.spad_write		= switchtec_ntb_spad_write,
499 	.peer_spad_write	= switchtec_ntb_peer_spad_write,
500 };
501 
502 static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
503 {
504 	u64 part_map;
505 
506 	sndev->ntb.pdev = sndev->stdev->pdev;
507 	sndev->ntb.topo = NTB_TOPO_SWITCH;
508 	sndev->ntb.ops = &switchtec_ntb_ops;
509 
510 	sndev->self_partition = sndev->stdev->partition;
511 
512 	sndev->mmio_ntb = sndev->stdev->mmio_ntb;
513 	part_map = ioread64(&sndev->mmio_ntb->ep_map);
514 	part_map &= ~(1 << sndev->self_partition);
515 	sndev->peer_partition = ffs(part_map) - 1;
516 
517 	dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d (%llx)",
518 		sndev->self_partition, sndev->stdev->partition_count,
519 		part_map);
520 
521 	sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb +
522 		SWITCHTEC_NTB_REG_CTRL_OFFSET;
523 	sndev->mmio_dbmsg = (void * __iomem)sndev->mmio_ntb +
524 		SWITCHTEC_NTB_REG_DBMSG_OFFSET;
525 
526 	sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition];
527 	sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition];
528 	sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition];
529 }
530 
531 static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
532 {
533 	int i;
534 	int cnt = 0;
535 
536 	for (i = 0; i < ARRAY_SIZE(ctrl->bar_entry); i++) {
537 		u32 r = ioread32(&ctrl->bar_entry[i].ctl);
538 
539 		if (r & NTB_CTRL_BAR_VALID)
540 			map[cnt++] = i;
541 	}
542 
543 	return cnt;
544 }
545 
546 static void switchtec_ntb_init_mw(struct switchtec_ntb *sndev)
547 {
548 	sndev->nr_direct_mw = map_bars(sndev->direct_mw_to_bar,
549 				       sndev->mmio_self_ctrl);
550 
551 	sndev->nr_lut_mw = ioread16(&sndev->mmio_self_ctrl->lut_table_entries);
552 	sndev->nr_lut_mw = rounddown_pow_of_two(sndev->nr_lut_mw);
553 
554 	dev_dbg(&sndev->stdev->dev, "MWs: %d direct, %d lut",
555 		sndev->nr_direct_mw, sndev->nr_lut_mw);
556 
557 	sndev->peer_nr_direct_mw = map_bars(sndev->peer_direct_mw_to_bar,
558 					    sndev->mmio_peer_ctrl);
559 
560 	sndev->peer_nr_lut_mw =
561 		ioread16(&sndev->mmio_peer_ctrl->lut_table_entries);
562 	sndev->peer_nr_lut_mw = rounddown_pow_of_two(sndev->peer_nr_lut_mw);
563 
564 	dev_dbg(&sndev->stdev->dev, "Peer MWs: %d direct, %d lut",
565 		sndev->peer_nr_direct_mw, sndev->peer_nr_lut_mw);
566 
567 }
568 
569 /*
570  * There are 64 doorbells in the switch hardware but this is
571  * shared among all partitions. So we must split them in half
572  * (32 for each partition). However, the message interrupts are
573  * also shared with the top 4 doorbells so we just limit this to
574  * 28 doorbells per partition
575  */
576 static void switchtec_ntb_init_db(struct switchtec_ntb *sndev)
577 {
578 	sndev->db_valid_mask = 0x0FFFFFFF;
579 
580 	if (sndev->self_partition < sndev->peer_partition) {
581 		sndev->db_shift = 0;
582 		sndev->db_peer_shift = 32;
583 	} else {
584 		sndev->db_shift = 32;
585 		sndev->db_peer_shift = 0;
586 	}
587 
588 	sndev->db_mask = 0x0FFFFFFFFFFFFFFFULL;
589 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
590 	iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
591 		  &sndev->mmio_self_dbmsg->odb_mask);
592 }
593 
594 static void switchtec_ntb_init_msgs(struct switchtec_ntb *sndev)
595 {
596 	int i;
597 	u32 msg_map = 0;
598 
599 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
600 		int m = i | sndev->peer_partition << 2;
601 
602 		msg_map |= m << i * 8;
603 	}
604 
605 	iowrite32(msg_map, &sndev->mmio_self_dbmsg->msg_map);
606 
607 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++)
608 		iowrite64(NTB_DBMSG_IMSG_STATUS | NTB_DBMSG_IMSG_MASK,
609 			  &sndev->mmio_self_dbmsg->imsg[i]);
610 }
611 
612 static int switchtec_ntb_init_req_id_table(struct switchtec_ntb *sndev)
613 {
614 	int rc = 0;
615 	u16 req_id;
616 	u32 error;
617 
618 	req_id = ioread16(&sndev->mmio_ntb->requester_id);
619 
620 	if (ioread32(&sndev->mmio_self_ctrl->req_id_table_size) < 2) {
621 		dev_err(&sndev->stdev->dev,
622 			"Not enough requester IDs available.");
623 		return -EFAULT;
624 	}
625 
626 	rc = switchtec_ntb_part_op(sndev, sndev->mmio_self_ctrl,
627 				   NTB_CTRL_PART_OP_LOCK,
628 				   NTB_CTRL_PART_STATUS_LOCKED);
629 	if (rc)
630 		return rc;
631 
632 	iowrite32(NTB_PART_CTRL_ID_PROT_DIS,
633 		  &sndev->mmio_self_ctrl->partition_ctrl);
634 
635 	/*
636 	 * Root Complex Requester ID (which is 0:00.0)
637 	 */
638 	iowrite32(0 << 16 | NTB_CTRL_REQ_ID_EN,
639 		  &sndev->mmio_self_ctrl->req_id_table[0]);
640 
641 	/*
642 	 * Host Bridge Requester ID (as read from the mmap address)
643 	 */
644 	iowrite32(req_id << 16 | NTB_CTRL_REQ_ID_EN,
645 		  &sndev->mmio_self_ctrl->req_id_table[1]);
646 
647 	rc = switchtec_ntb_part_op(sndev, sndev->mmio_self_ctrl,
648 				   NTB_CTRL_PART_OP_CFG,
649 				   NTB_CTRL_PART_STATUS_NORMAL);
650 	if (rc == -EIO) {
651 		error = ioread32(&sndev->mmio_self_ctrl->req_id_error);
652 		dev_err(&sndev->stdev->dev,
653 			"Error setting up the requester ID table: %08x",
654 			error);
655 	}
656 
657 	return rc;
658 }
659 
660 static void switchtec_ntb_init_shared(struct switchtec_ntb *sndev)
661 {
662 	int i;
663 
664 	memset(sndev->self_shared, 0, LUT_SIZE);
665 	sndev->self_shared->magic = SWITCHTEC_NTB_MAGIC;
666 	sndev->self_shared->partition_id = sndev->stdev->partition;
667 
668 	for (i = 0; i < sndev->nr_direct_mw; i++) {
669 		int bar = sndev->direct_mw_to_bar[i];
670 		resource_size_t sz = pci_resource_len(sndev->stdev->pdev, bar);
671 
672 		if (i == 0)
673 			sz = min_t(resource_size_t, sz,
674 				   LUT_SIZE * sndev->nr_lut_mw);
675 
676 		sndev->self_shared->mw_sizes[i] = sz;
677 	}
678 
679 	for (i = 0; i < sndev->nr_lut_mw; i++) {
680 		int idx = sndev->nr_direct_mw + i;
681 
682 		sndev->self_shared->mw_sizes[idx] = LUT_SIZE;
683 	}
684 }
685 
686 static int switchtec_ntb_init_shared_mw(struct switchtec_ntb *sndev)
687 {
688 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
689 	int bar = sndev->direct_mw_to_bar[0];
690 	u32 ctl_val;
691 	int rc;
692 
693 	sndev->self_shared = dma_zalloc_coherent(&sndev->stdev->pdev->dev,
694 						 LUT_SIZE,
695 						 &sndev->self_shared_dma,
696 						 GFP_KERNEL);
697 	if (!sndev->self_shared) {
698 		dev_err(&sndev->stdev->dev,
699 			"unable to allocate memory for shared mw");
700 		return -ENOMEM;
701 	}
702 
703 	switchtec_ntb_init_shared(sndev);
704 
705 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
706 				   NTB_CTRL_PART_STATUS_LOCKED);
707 	if (rc)
708 		goto unalloc_and_exit;
709 
710 	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
711 	ctl_val &= 0xFF;
712 	ctl_val |= NTB_CTRL_BAR_LUT_WIN_EN;
713 	ctl_val |= ilog2(LUT_SIZE) << 8;
714 	ctl_val |= (sndev->nr_lut_mw - 1) << 14;
715 	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
716 
717 	iowrite64((NTB_CTRL_LUT_EN | (sndev->self_partition << 1) |
718 		   sndev->self_shared_dma),
719 		  &ctl->lut_entry[0]);
720 
721 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
722 				   NTB_CTRL_PART_STATUS_NORMAL);
723 	if (rc) {
724 		u32 bar_error, lut_error;
725 
726 		bar_error = ioread32(&ctl->bar_error);
727 		lut_error = ioread32(&ctl->lut_error);
728 		dev_err(&sndev->stdev->dev,
729 			"Error setting up shared MW: %08x / %08x",
730 			bar_error, lut_error);
731 		goto unalloc_and_exit;
732 	}
733 
734 	sndev->peer_shared = pci_iomap(sndev->stdev->pdev, bar, LUT_SIZE);
735 	if (!sndev->peer_shared) {
736 		rc = -ENOMEM;
737 		goto unalloc_and_exit;
738 	}
739 
740 	dev_dbg(&sndev->stdev->dev, "Shared MW Ready");
741 	return 0;
742 
743 unalloc_and_exit:
744 	dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
745 			  sndev->self_shared, sndev->self_shared_dma);
746 
747 	return rc;
748 }
749 
750 static void switchtec_ntb_deinit_shared_mw(struct switchtec_ntb *sndev)
751 {
752 	if (sndev->peer_shared)
753 		pci_iounmap(sndev->stdev->pdev, sndev->peer_shared);
754 
755 	if (sndev->self_shared)
756 		dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
757 				  sndev->self_shared,
758 				  sndev->self_shared_dma);
759 }
760 
761 static irqreturn_t switchtec_ntb_doorbell_isr(int irq, void *dev)
762 {
763 	struct switchtec_ntb *sndev = dev;
764 
765 	dev_dbg(&sndev->stdev->dev, "doorbell\n");
766 
767 	ntb_db_event(&sndev->ntb, 0);
768 
769 	return IRQ_HANDLED;
770 }
771 
772 static irqreturn_t switchtec_ntb_message_isr(int irq, void *dev)
773 {
774 	int i;
775 	struct switchtec_ntb *sndev = dev;
776 
777 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
778 		u64 msg = ioread64(&sndev->mmio_self_dbmsg->imsg[i]);
779 
780 		if (msg & NTB_DBMSG_IMSG_STATUS) {
781 			dev_dbg(&sndev->stdev->dev, "message: %d %08x\n", i,
782 				(u32)msg);
783 			iowrite8(1, &sndev->mmio_self_dbmsg->imsg[i].status);
784 
785 			if (i == LINK_MESSAGE)
786 				switchtec_ntb_check_link(sndev);
787 		}
788 	}
789 
790 	return IRQ_HANDLED;
791 }
792 
793 static int switchtec_ntb_init_db_msg_irq(struct switchtec_ntb *sndev)
794 {
795 	int i;
796 	int rc;
797 	int doorbell_irq = 0;
798 	int message_irq = 0;
799 	int event_irq;
800 	int idb_vecs = sizeof(sndev->mmio_self_dbmsg->idb_vec_map);
801 
802 	event_irq = ioread32(&sndev->stdev->mmio_part_cfg->vep_vector_number);
803 
804 	while (doorbell_irq == event_irq)
805 		doorbell_irq++;
806 	while (message_irq == doorbell_irq ||
807 	       message_irq == event_irq)
808 		message_irq++;
809 
810 	dev_dbg(&sndev->stdev->dev, "irqs - event: %d, db: %d, msgs: %d",
811 		event_irq, doorbell_irq, message_irq);
812 
813 	for (i = 0; i < idb_vecs - 4; i++)
814 		iowrite8(doorbell_irq,
815 			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
816 
817 	for (; i < idb_vecs; i++)
818 		iowrite8(message_irq,
819 			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
820 
821 	sndev->doorbell_irq = pci_irq_vector(sndev->stdev->pdev, doorbell_irq);
822 	sndev->message_irq = pci_irq_vector(sndev->stdev->pdev, message_irq);
823 
824 	rc = request_irq(sndev->doorbell_irq,
825 			 switchtec_ntb_doorbell_isr, 0,
826 			 "switchtec_ntb_doorbell", sndev);
827 	if (rc)
828 		return rc;
829 
830 	rc = request_irq(sndev->message_irq,
831 			 switchtec_ntb_message_isr, 0,
832 			 "switchtec_ntb_message", sndev);
833 	if (rc) {
834 		free_irq(sndev->doorbell_irq, sndev);
835 		return rc;
836 	}
837 
838 	return 0;
839 }
840 
841 static void switchtec_ntb_deinit_db_msg_irq(struct switchtec_ntb *sndev)
842 {
843 	free_irq(sndev->doorbell_irq, sndev);
844 	free_irq(sndev->message_irq, sndev);
845 }
846 
847 static int switchtec_ntb_add(struct device *dev,
848 			     struct class_interface *class_intf)
849 {
850 	struct switchtec_dev *stdev = to_stdev(dev);
851 	struct switchtec_ntb *sndev;
852 	int rc;
853 
854 	stdev->sndev = NULL;
855 
856 	if (stdev->pdev->class != MICROSEMI_NTB_CLASSCODE)
857 		return -ENODEV;
858 
859 	if (stdev->partition_count != 2)
860 		dev_warn(dev, "ntb driver only supports 2 partitions");
861 
862 	sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev));
863 	if (!sndev)
864 		return -ENOMEM;
865 
866 	sndev->stdev = stdev;
867 	switchtec_ntb_init_sndev(sndev);
868 	switchtec_ntb_init_mw(sndev);
869 	switchtec_ntb_init_db(sndev);
870 	switchtec_ntb_init_msgs(sndev);
871 
872 	rc = switchtec_ntb_init_req_id_table(sndev);
873 	if (rc)
874 		goto free_and_exit;
875 
876 	rc = switchtec_ntb_init_shared_mw(sndev);
877 	if (rc)
878 		goto free_and_exit;
879 
880 	rc = switchtec_ntb_init_db_msg_irq(sndev);
881 	if (rc)
882 		goto deinit_shared_and_exit;
883 
884 	rc = ntb_register_device(&sndev->ntb);
885 	if (rc)
886 		goto deinit_and_exit;
887 
888 	stdev->sndev = sndev;
889 	stdev->link_notifier = switchtec_ntb_link_notification;
890 	dev_info(dev, "NTB device registered");
891 
892 	return 0;
893 
894 deinit_and_exit:
895 	switchtec_ntb_deinit_db_msg_irq(sndev);
896 deinit_shared_and_exit:
897 	switchtec_ntb_deinit_shared_mw(sndev);
898 free_and_exit:
899 	kfree(sndev);
900 	dev_err(dev, "failed to register ntb device: %d", rc);
901 	return rc;
902 }
903 
904 void switchtec_ntb_remove(struct device *dev,
905 			  struct class_interface *class_intf)
906 {
907 	struct switchtec_dev *stdev = to_stdev(dev);
908 	struct switchtec_ntb *sndev = stdev->sndev;
909 
910 	if (!sndev)
911 		return;
912 
913 	stdev->link_notifier = NULL;
914 	stdev->sndev = NULL;
915 	ntb_unregister_device(&sndev->ntb);
916 	switchtec_ntb_deinit_db_msg_irq(sndev);
917 	switchtec_ntb_deinit_shared_mw(sndev);
918 	kfree(sndev);
919 	dev_info(dev, "ntb device unregistered");
920 }
921 
922 static struct class_interface switchtec_interface  = {
923 	.add_dev = switchtec_ntb_add,
924 	.remove_dev = switchtec_ntb_remove,
925 };
926 
927 static int __init switchtec_ntb_init(void)
928 {
929 	switchtec_interface.class = switchtec_class;
930 	return class_interface_register(&switchtec_interface);
931 }
932 module_init(switchtec_ntb_init);
933 
934 static void __exit switchtec_ntb_exit(void)
935 {
936 	class_interface_unregister(&switchtec_interface);
937 }
938 module_exit(switchtec_ntb_exit);
939