xref: /linux/drivers/ntb/hw/mscc/ntb_hw_switchtec.c (revision d04be142b8b61ffb3c9cc5c6d1abda8fc59a16c9)
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 ulong max_mw_size = SZ_2M;
29 module_param(max_mw_size, ulong, 0644);
30 MODULE_PARM_DESC(max_mw_size,
31 	"Max memory window size reported to the upper layer");
32 
33 static bool use_lut_mws;
34 module_param(use_lut_mws, bool, 0644);
35 MODULE_PARM_DESC(use_lut_mws,
36 		 "Enable the use of the LUT based memory windows");
37 
38 #ifndef ioread64
39 #ifdef readq
40 #define ioread64 readq
41 #else
42 #define ioread64 _ioread64
43 static inline u64 _ioread64(void __iomem *mmio)
44 {
45 	u64 low, high;
46 
47 	low = ioread32(mmio);
48 	high = ioread32(mmio + sizeof(u32));
49 	return low | (high << 32);
50 }
51 #endif
52 #endif
53 
54 #ifndef iowrite64
55 #ifdef writeq
56 #define iowrite64 writeq
57 #else
58 #define iowrite64 _iowrite64
59 static inline void _iowrite64(u64 val, void __iomem *mmio)
60 {
61 	iowrite32(val, mmio);
62 	iowrite32(val >> 32, mmio + sizeof(u32));
63 }
64 #endif
65 #endif
66 
67 #define SWITCHTEC_NTB_MAGIC 0x45CC0001
68 #define MAX_MWS     128
69 
70 struct shared_mw {
71 	u32 magic;
72 	u32 link_sta;
73 	u32 partition_id;
74 	u64 mw_sizes[MAX_MWS];
75 	u32 spad[128];
76 };
77 
78 #define MAX_DIRECT_MW ARRAY_SIZE(((struct ntb_ctrl_regs *)(0))->bar_entry)
79 #define LUT_SIZE SZ_64K
80 
81 struct switchtec_ntb {
82 	struct ntb_dev ntb;
83 	struct switchtec_dev *stdev;
84 
85 	int self_partition;
86 	int peer_partition;
87 
88 	int doorbell_irq;
89 	int message_irq;
90 
91 	struct ntb_info_regs __iomem *mmio_ntb;
92 	struct ntb_ctrl_regs __iomem *mmio_ctrl;
93 	struct ntb_dbmsg_regs __iomem *mmio_dbmsg;
94 	struct ntb_ctrl_regs __iomem *mmio_self_ctrl;
95 	struct ntb_ctrl_regs __iomem *mmio_peer_ctrl;
96 	struct ntb_dbmsg_regs __iomem *mmio_self_dbmsg;
97 	struct ntb_dbmsg_regs __iomem *mmio_peer_dbmsg;
98 
99 	void __iomem *mmio_xlink_win;
100 
101 	struct shared_mw *self_shared;
102 	struct shared_mw __iomem *peer_shared;
103 	dma_addr_t self_shared_dma;
104 
105 	u64 db_mask;
106 	u64 db_valid_mask;
107 	int db_shift;
108 	int db_peer_shift;
109 
110 	/* synchronize rmw access of db_mask and hw reg */
111 	spinlock_t db_mask_lock;
112 
113 	int nr_direct_mw;
114 	int nr_lut_mw;
115 	int nr_rsvd_luts;
116 	int direct_mw_to_bar[MAX_DIRECT_MW];
117 
118 	int peer_nr_direct_mw;
119 	int peer_nr_lut_mw;
120 	int peer_direct_mw_to_bar[MAX_DIRECT_MW];
121 
122 	bool link_is_up;
123 	enum ntb_speed link_speed;
124 	enum ntb_width link_width;
125 	struct work_struct link_reinit_work;
126 };
127 
128 static struct switchtec_ntb *ntb_sndev(struct ntb_dev *ntb)
129 {
130 	return container_of(ntb, struct switchtec_ntb, ntb);
131 }
132 
133 static int switchtec_ntb_part_op(struct switchtec_ntb *sndev,
134 				 struct ntb_ctrl_regs __iomem *ctl,
135 				 u32 op, int wait_status)
136 {
137 	static const char * const op_text[] = {
138 		[NTB_CTRL_PART_OP_LOCK] = "lock",
139 		[NTB_CTRL_PART_OP_CFG] = "configure",
140 		[NTB_CTRL_PART_OP_RESET] = "reset",
141 	};
142 
143 	int i;
144 	u32 ps;
145 	int status;
146 
147 	switch (op) {
148 	case NTB_CTRL_PART_OP_LOCK:
149 		status = NTB_CTRL_PART_STATUS_LOCKING;
150 		break;
151 	case NTB_CTRL_PART_OP_CFG:
152 		status = NTB_CTRL_PART_STATUS_CONFIGURING;
153 		break;
154 	case NTB_CTRL_PART_OP_RESET:
155 		status = NTB_CTRL_PART_STATUS_RESETTING;
156 		break;
157 	default:
158 		return -EINVAL;
159 	}
160 
161 	iowrite32(op, &ctl->partition_op);
162 
163 	for (i = 0; i < 1000; i++) {
164 		if (msleep_interruptible(50) != 0) {
165 			iowrite32(NTB_CTRL_PART_OP_RESET, &ctl->partition_op);
166 			return -EINTR;
167 		}
168 
169 		ps = ioread32(&ctl->partition_status) & 0xFFFF;
170 
171 		if (ps != status)
172 			break;
173 	}
174 
175 	if (ps == wait_status)
176 		return 0;
177 
178 	if (ps == status) {
179 		dev_err(&sndev->stdev->dev,
180 			"Timed out while performing %s (%d). (%08x)\n",
181 			op_text[op], op,
182 			ioread32(&ctl->partition_status));
183 
184 		return -ETIMEDOUT;
185 	}
186 
187 	return -EIO;
188 }
189 
190 static int switchtec_ntb_send_msg(struct switchtec_ntb *sndev, int idx,
191 				  u32 val)
192 {
193 	if (idx < 0 || idx >= ARRAY_SIZE(sndev->mmio_peer_dbmsg->omsg))
194 		return -EINVAL;
195 
196 	iowrite32(val, &sndev->mmio_peer_dbmsg->omsg[idx].msg);
197 
198 	return 0;
199 }
200 
201 static int switchtec_ntb_mw_count(struct ntb_dev *ntb, int pidx)
202 {
203 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
204 	int nr_direct_mw = sndev->peer_nr_direct_mw;
205 	int nr_lut_mw = sndev->peer_nr_lut_mw - sndev->nr_rsvd_luts;
206 
207 	if (pidx != NTB_DEF_PEER_IDX)
208 		return -EINVAL;
209 
210 	if (!use_lut_mws)
211 		nr_lut_mw = 0;
212 
213 	return nr_direct_mw + nr_lut_mw;
214 }
215 
216 static int lut_index(struct switchtec_ntb *sndev, int mw_idx)
217 {
218 	return mw_idx - sndev->nr_direct_mw + sndev->nr_rsvd_luts;
219 }
220 
221 static int peer_lut_index(struct switchtec_ntb *sndev, int mw_idx)
222 {
223 	return mw_idx - sndev->peer_nr_direct_mw + sndev->nr_rsvd_luts;
224 }
225 
226 static int switchtec_ntb_mw_get_align(struct ntb_dev *ntb, int pidx,
227 				      int widx, resource_size_t *addr_align,
228 				      resource_size_t *size_align,
229 				      resource_size_t *size_max)
230 {
231 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
232 	int lut;
233 	resource_size_t size;
234 
235 	if (pidx != NTB_DEF_PEER_IDX)
236 		return -EINVAL;
237 
238 	lut = widx >= sndev->peer_nr_direct_mw;
239 	size = ioread64(&sndev->peer_shared->mw_sizes[widx]);
240 
241 	if (size == 0)
242 		return -EINVAL;
243 
244 	if (addr_align)
245 		*addr_align = lut ? size : SZ_4K;
246 
247 	if (size_align)
248 		*size_align = lut ? size : SZ_4K;
249 
250 	if (size_max)
251 		*size_max = size;
252 
253 	return 0;
254 }
255 
256 static void switchtec_ntb_mw_clr_direct(struct switchtec_ntb *sndev, int idx)
257 {
258 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
259 	int bar = sndev->peer_direct_mw_to_bar[idx];
260 	u32 ctl_val;
261 
262 	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
263 	ctl_val &= ~NTB_CTRL_BAR_DIR_WIN_EN;
264 	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
265 	iowrite32(0, &ctl->bar_entry[bar].win_size);
266 	iowrite64(sndev->self_partition, &ctl->bar_entry[bar].xlate_addr);
267 }
268 
269 static void switchtec_ntb_mw_clr_lut(struct switchtec_ntb *sndev, int idx)
270 {
271 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
272 
273 	iowrite64(0, &ctl->lut_entry[peer_lut_index(sndev, idx)]);
274 }
275 
276 static void switchtec_ntb_mw_set_direct(struct switchtec_ntb *sndev, int idx,
277 					dma_addr_t addr, resource_size_t size)
278 {
279 	int xlate_pos = ilog2(size);
280 	int bar = sndev->peer_direct_mw_to_bar[idx];
281 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
282 	u32 ctl_val;
283 
284 	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
285 	ctl_val |= NTB_CTRL_BAR_DIR_WIN_EN;
286 
287 	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
288 	iowrite32(xlate_pos | size, &ctl->bar_entry[bar].win_size);
289 	iowrite64(sndev->self_partition | addr,
290 		  &ctl->bar_entry[bar].xlate_addr);
291 }
292 
293 static void switchtec_ntb_mw_set_lut(struct switchtec_ntb *sndev, int idx,
294 				     dma_addr_t addr, resource_size_t size)
295 {
296 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
297 
298 	iowrite64((NTB_CTRL_LUT_EN | (sndev->self_partition << 1) | addr),
299 		  &ctl->lut_entry[peer_lut_index(sndev, idx)]);
300 }
301 
302 static int switchtec_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx,
303 				      dma_addr_t addr, resource_size_t size)
304 {
305 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
306 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
307 	int xlate_pos = ilog2(size);
308 	int nr_direct_mw = sndev->peer_nr_direct_mw;
309 	int rc;
310 
311 	if (pidx != NTB_DEF_PEER_IDX)
312 		return -EINVAL;
313 
314 	dev_dbg(&sndev->stdev->dev, "MW %d: part %d addr %pad size %pap\n",
315 		widx, pidx, &addr, &size);
316 
317 	if (widx >= switchtec_ntb_mw_count(ntb, pidx))
318 		return -EINVAL;
319 
320 	if (xlate_pos < 12)
321 		return -EINVAL;
322 
323 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
324 				   NTB_CTRL_PART_STATUS_LOCKED);
325 	if (rc)
326 		return rc;
327 
328 	if (addr == 0 || size == 0) {
329 		if (widx < nr_direct_mw)
330 			switchtec_ntb_mw_clr_direct(sndev, widx);
331 		else
332 			switchtec_ntb_mw_clr_lut(sndev, widx);
333 	} else {
334 		if (widx < nr_direct_mw)
335 			switchtec_ntb_mw_set_direct(sndev, widx, addr, size);
336 		else
337 			switchtec_ntb_mw_set_lut(sndev, widx, addr, size);
338 	}
339 
340 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
341 				   NTB_CTRL_PART_STATUS_NORMAL);
342 
343 	if (rc == -EIO) {
344 		dev_err(&sndev->stdev->dev,
345 			"Hardware reported an error configuring mw %d: %08x\n",
346 			widx, ioread32(&ctl->bar_error));
347 
348 		if (widx < nr_direct_mw)
349 			switchtec_ntb_mw_clr_direct(sndev, widx);
350 		else
351 			switchtec_ntb_mw_clr_lut(sndev, widx);
352 
353 		switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
354 				      NTB_CTRL_PART_STATUS_NORMAL);
355 	}
356 
357 	return rc;
358 }
359 
360 static int switchtec_ntb_peer_mw_count(struct ntb_dev *ntb)
361 {
362 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
363 	int nr_lut_mw = sndev->nr_lut_mw - sndev->nr_rsvd_luts;
364 
365 	return sndev->nr_direct_mw + (use_lut_mws ? nr_lut_mw : 0);
366 }
367 
368 static int switchtec_ntb_direct_get_addr(struct switchtec_ntb *sndev,
369 					 int idx, phys_addr_t *base,
370 					 resource_size_t *size)
371 {
372 	int bar = sndev->direct_mw_to_bar[idx];
373 	size_t offset = 0;
374 
375 	if (bar < 0)
376 		return -EINVAL;
377 
378 	if (idx == 0) {
379 		/*
380 		 * This is the direct BAR shared with the LUTs
381 		 * which means the actual window will be offset
382 		 * by the size of all the LUT entries.
383 		 */
384 
385 		offset = LUT_SIZE * sndev->nr_lut_mw;
386 	}
387 
388 	if (base)
389 		*base = pci_resource_start(sndev->ntb.pdev, bar) + offset;
390 
391 	if (size) {
392 		*size = pci_resource_len(sndev->ntb.pdev, bar) - offset;
393 		if (offset && *size > offset)
394 			*size = offset;
395 
396 		if (*size > max_mw_size)
397 			*size = max_mw_size;
398 	}
399 
400 	return 0;
401 }
402 
403 static int switchtec_ntb_lut_get_addr(struct switchtec_ntb *sndev,
404 				      int idx, phys_addr_t *base,
405 				      resource_size_t *size)
406 {
407 	int bar = sndev->direct_mw_to_bar[0];
408 	int offset;
409 
410 	offset = LUT_SIZE * lut_index(sndev, idx);
411 
412 	if (base)
413 		*base = pci_resource_start(sndev->ntb.pdev, bar) + offset;
414 
415 	if (size)
416 		*size = LUT_SIZE;
417 
418 	return 0;
419 }
420 
421 static int switchtec_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
422 					  phys_addr_t *base,
423 					  resource_size_t *size)
424 {
425 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
426 
427 	if (idx < sndev->nr_direct_mw)
428 		return switchtec_ntb_direct_get_addr(sndev, idx, base, size);
429 	else if (idx < switchtec_ntb_peer_mw_count(ntb))
430 		return switchtec_ntb_lut_get_addr(sndev, idx, base, size);
431 	else
432 		return -EINVAL;
433 }
434 
435 static void switchtec_ntb_part_link_speed(struct switchtec_ntb *sndev,
436 					  int partition,
437 					  enum ntb_speed *speed,
438 					  enum ntb_width *width)
439 {
440 	struct switchtec_dev *stdev = sndev->stdev;
441 
442 	u32 pff = ioread32(&stdev->mmio_part_cfg[partition].vep_pff_inst_id);
443 	u32 linksta = ioread32(&stdev->mmio_pff_csr[pff].pci_cap_region[13]);
444 
445 	if (speed)
446 		*speed = (linksta >> 16) & 0xF;
447 
448 	if (width)
449 		*width = (linksta >> 20) & 0x3F;
450 }
451 
452 static void switchtec_ntb_set_link_speed(struct switchtec_ntb *sndev)
453 {
454 	enum ntb_speed self_speed, peer_speed;
455 	enum ntb_width self_width, peer_width;
456 
457 	if (!sndev->link_is_up) {
458 		sndev->link_speed = NTB_SPEED_NONE;
459 		sndev->link_width = NTB_WIDTH_NONE;
460 		return;
461 	}
462 
463 	switchtec_ntb_part_link_speed(sndev, sndev->self_partition,
464 				      &self_speed, &self_width);
465 	switchtec_ntb_part_link_speed(sndev, sndev->peer_partition,
466 				      &peer_speed, &peer_width);
467 
468 	sndev->link_speed = min(self_speed, peer_speed);
469 	sndev->link_width = min(self_width, peer_width);
470 }
471 
472 static int crosslink_is_enabled(struct switchtec_ntb *sndev)
473 {
474 	struct ntb_info_regs __iomem *inf = sndev->mmio_ntb;
475 
476 	return ioread8(&inf->ntp_info[sndev->peer_partition].xlink_enabled);
477 }
478 
479 static void crosslink_init_dbmsgs(struct switchtec_ntb *sndev)
480 {
481 	int i;
482 	u32 msg_map = 0;
483 
484 	if (!crosslink_is_enabled(sndev))
485 		return;
486 
487 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_peer_dbmsg->imsg); i++) {
488 		int m = i | sndev->self_partition << 2;
489 
490 		msg_map |= m << i * 8;
491 	}
492 
493 	iowrite32(msg_map, &sndev->mmio_peer_dbmsg->msg_map);
494 	iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
495 		  &sndev->mmio_peer_dbmsg->odb_mask);
496 }
497 
498 enum switchtec_msg {
499 	LINK_MESSAGE = 0,
500 	MSG_LINK_UP = 1,
501 	MSG_LINK_DOWN = 2,
502 	MSG_CHECK_LINK = 3,
503 	MSG_LINK_FORCE_DOWN = 4,
504 };
505 
506 static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev);
507 
508 static void link_reinit_work(struct work_struct *work)
509 {
510 	struct switchtec_ntb *sndev;
511 
512 	sndev = container_of(work, struct switchtec_ntb, link_reinit_work);
513 
514 	switchtec_ntb_reinit_peer(sndev);
515 }
516 
517 static void switchtec_ntb_check_link(struct switchtec_ntb *sndev,
518 				     enum switchtec_msg msg)
519 {
520 	int link_sta;
521 	int old = sndev->link_is_up;
522 
523 	if (msg == MSG_LINK_FORCE_DOWN) {
524 		schedule_work(&sndev->link_reinit_work);
525 
526 		if (sndev->link_is_up) {
527 			sndev->link_is_up = 0;
528 			ntb_link_event(&sndev->ntb);
529 			dev_info(&sndev->stdev->dev, "ntb link forced down\n");
530 		}
531 
532 		return;
533 	}
534 
535 	link_sta = sndev->self_shared->link_sta;
536 	if (link_sta) {
537 		u64 peer = ioread64(&sndev->peer_shared->magic);
538 
539 		if ((peer & 0xFFFFFFFF) == SWITCHTEC_NTB_MAGIC)
540 			link_sta = peer >> 32;
541 		else
542 			link_sta = 0;
543 	}
544 
545 	sndev->link_is_up = link_sta;
546 	switchtec_ntb_set_link_speed(sndev);
547 
548 	if (link_sta != old) {
549 		switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_CHECK_LINK);
550 		ntb_link_event(&sndev->ntb);
551 		dev_info(&sndev->stdev->dev, "ntb link %s\n",
552 			 link_sta ? "up" : "down");
553 
554 		if (link_sta)
555 			crosslink_init_dbmsgs(sndev);
556 	}
557 }
558 
559 static void switchtec_ntb_link_notification(struct switchtec_dev *stdev)
560 {
561 	struct switchtec_ntb *sndev = stdev->sndev;
562 
563 	switchtec_ntb_check_link(sndev, MSG_CHECK_LINK);
564 }
565 
566 static u64 switchtec_ntb_link_is_up(struct ntb_dev *ntb,
567 				    enum ntb_speed *speed,
568 				    enum ntb_width *width)
569 {
570 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
571 
572 	if (speed)
573 		*speed = sndev->link_speed;
574 	if (width)
575 		*width = sndev->link_width;
576 
577 	return sndev->link_is_up;
578 }
579 
580 static int switchtec_ntb_link_enable(struct ntb_dev *ntb,
581 				     enum ntb_speed max_speed,
582 				     enum ntb_width max_width)
583 {
584 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
585 
586 	dev_dbg(&sndev->stdev->dev, "enabling link\n");
587 
588 	sndev->self_shared->link_sta = 1;
589 	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_UP);
590 
591 	switchtec_ntb_check_link(sndev, MSG_CHECK_LINK);
592 
593 	return 0;
594 }
595 
596 static int switchtec_ntb_link_disable(struct ntb_dev *ntb)
597 {
598 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
599 
600 	dev_dbg(&sndev->stdev->dev, "disabling link\n");
601 
602 	sndev->self_shared->link_sta = 0;
603 	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_DOWN);
604 
605 	switchtec_ntb_check_link(sndev, MSG_CHECK_LINK);
606 
607 	return 0;
608 }
609 
610 static u64 switchtec_ntb_db_valid_mask(struct ntb_dev *ntb)
611 {
612 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
613 
614 	return sndev->db_valid_mask;
615 }
616 
617 static int switchtec_ntb_db_vector_count(struct ntb_dev *ntb)
618 {
619 	return 1;
620 }
621 
622 static u64 switchtec_ntb_db_vector_mask(struct ntb_dev *ntb, int db_vector)
623 {
624 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
625 
626 	if (db_vector < 0 || db_vector > 1)
627 		return 0;
628 
629 	return sndev->db_valid_mask;
630 }
631 
632 static u64 switchtec_ntb_db_read(struct ntb_dev *ntb)
633 {
634 	u64 ret;
635 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
636 
637 	ret = ioread64(&sndev->mmio_self_dbmsg->idb) >> sndev->db_shift;
638 
639 	return ret & sndev->db_valid_mask;
640 }
641 
642 static int switchtec_ntb_db_clear(struct ntb_dev *ntb, u64 db_bits)
643 {
644 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
645 
646 	iowrite64(db_bits << sndev->db_shift, &sndev->mmio_self_dbmsg->idb);
647 
648 	return 0;
649 }
650 
651 static int switchtec_ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
652 {
653 	unsigned long irqflags;
654 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
655 
656 	if (db_bits & ~sndev->db_valid_mask)
657 		return -EINVAL;
658 
659 	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
660 
661 	sndev->db_mask |= db_bits << sndev->db_shift;
662 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
663 
664 	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
665 
666 	return 0;
667 }
668 
669 static int switchtec_ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
670 {
671 	unsigned long irqflags;
672 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
673 
674 	if (db_bits & ~sndev->db_valid_mask)
675 		return -EINVAL;
676 
677 	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
678 
679 	sndev->db_mask &= ~(db_bits << sndev->db_shift);
680 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
681 
682 	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
683 
684 	return 0;
685 }
686 
687 static u64 switchtec_ntb_db_read_mask(struct ntb_dev *ntb)
688 {
689 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
690 
691 	return (sndev->db_mask >> sndev->db_shift) & sndev->db_valid_mask;
692 }
693 
694 static int switchtec_ntb_peer_db_addr(struct ntb_dev *ntb,
695 				      phys_addr_t *db_addr,
696 				      resource_size_t *db_size)
697 {
698 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
699 	unsigned long offset;
700 
701 	offset = (unsigned long)sndev->mmio_peer_dbmsg->odb -
702 		(unsigned long)sndev->stdev->mmio;
703 
704 	offset += sndev->db_shift / 8;
705 
706 	if (db_addr)
707 		*db_addr = pci_resource_start(ntb->pdev, 0) + offset;
708 	if (db_size)
709 		*db_size = sizeof(u32);
710 
711 	return 0;
712 }
713 
714 static int switchtec_ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
715 {
716 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
717 
718 	iowrite64(db_bits << sndev->db_peer_shift,
719 		  &sndev->mmio_peer_dbmsg->odb);
720 
721 	return 0;
722 }
723 
724 static int switchtec_ntb_spad_count(struct ntb_dev *ntb)
725 {
726 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
727 
728 	return ARRAY_SIZE(sndev->self_shared->spad);
729 }
730 
731 static u32 switchtec_ntb_spad_read(struct ntb_dev *ntb, int idx)
732 {
733 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
734 
735 	if (idx < 0 || idx >= ARRAY_SIZE(sndev->self_shared->spad))
736 		return 0;
737 
738 	if (!sndev->self_shared)
739 		return 0;
740 
741 	return sndev->self_shared->spad[idx];
742 }
743 
744 static int switchtec_ntb_spad_write(struct ntb_dev *ntb, int idx, u32 val)
745 {
746 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
747 
748 	if (idx < 0 || idx >= ARRAY_SIZE(sndev->self_shared->spad))
749 		return -EINVAL;
750 
751 	if (!sndev->self_shared)
752 		return -EIO;
753 
754 	sndev->self_shared->spad[idx] = val;
755 
756 	return 0;
757 }
758 
759 static u32 switchtec_ntb_peer_spad_read(struct ntb_dev *ntb, int pidx,
760 					int sidx)
761 {
762 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
763 
764 	if (pidx != NTB_DEF_PEER_IDX)
765 		return -EINVAL;
766 
767 	if (sidx < 0 || sidx >= ARRAY_SIZE(sndev->peer_shared->spad))
768 		return 0;
769 
770 	if (!sndev->peer_shared)
771 		return 0;
772 
773 	return ioread32(&sndev->peer_shared->spad[sidx]);
774 }
775 
776 static int switchtec_ntb_peer_spad_write(struct ntb_dev *ntb, int pidx,
777 					 int sidx, u32 val)
778 {
779 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
780 
781 	if (pidx != NTB_DEF_PEER_IDX)
782 		return -EINVAL;
783 
784 	if (sidx < 0 || sidx >= ARRAY_SIZE(sndev->peer_shared->spad))
785 		return -EINVAL;
786 
787 	if (!sndev->peer_shared)
788 		return -EIO;
789 
790 	iowrite32(val, &sndev->peer_shared->spad[sidx]);
791 
792 	return 0;
793 }
794 
795 static int switchtec_ntb_peer_spad_addr(struct ntb_dev *ntb, int pidx,
796 					int sidx, phys_addr_t *spad_addr)
797 {
798 	struct switchtec_ntb *sndev = ntb_sndev(ntb);
799 	unsigned long offset;
800 
801 	if (pidx != NTB_DEF_PEER_IDX)
802 		return -EINVAL;
803 
804 	offset = (unsigned long)&sndev->peer_shared->spad[sidx] -
805 		(unsigned long)sndev->stdev->mmio;
806 
807 	if (spad_addr)
808 		*spad_addr = pci_resource_start(ntb->pdev, 0) + offset;
809 
810 	return 0;
811 }
812 
813 static const struct ntb_dev_ops switchtec_ntb_ops = {
814 	.mw_count		= switchtec_ntb_mw_count,
815 	.mw_get_align		= switchtec_ntb_mw_get_align,
816 	.mw_set_trans		= switchtec_ntb_mw_set_trans,
817 	.peer_mw_count		= switchtec_ntb_peer_mw_count,
818 	.peer_mw_get_addr	= switchtec_ntb_peer_mw_get_addr,
819 	.link_is_up		= switchtec_ntb_link_is_up,
820 	.link_enable		= switchtec_ntb_link_enable,
821 	.link_disable		= switchtec_ntb_link_disable,
822 	.db_valid_mask		= switchtec_ntb_db_valid_mask,
823 	.db_vector_count	= switchtec_ntb_db_vector_count,
824 	.db_vector_mask		= switchtec_ntb_db_vector_mask,
825 	.db_read		= switchtec_ntb_db_read,
826 	.db_clear		= switchtec_ntb_db_clear,
827 	.db_set_mask		= switchtec_ntb_db_set_mask,
828 	.db_clear_mask		= switchtec_ntb_db_clear_mask,
829 	.db_read_mask		= switchtec_ntb_db_read_mask,
830 	.peer_db_addr		= switchtec_ntb_peer_db_addr,
831 	.peer_db_set		= switchtec_ntb_peer_db_set,
832 	.spad_count		= switchtec_ntb_spad_count,
833 	.spad_read		= switchtec_ntb_spad_read,
834 	.spad_write		= switchtec_ntb_spad_write,
835 	.peer_spad_read		= switchtec_ntb_peer_spad_read,
836 	.peer_spad_write	= switchtec_ntb_peer_spad_write,
837 	.peer_spad_addr		= switchtec_ntb_peer_spad_addr,
838 };
839 
840 static int switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
841 {
842 	u64 tpart_vec;
843 	int self;
844 	u64 part_map;
845 	int bit;
846 
847 	sndev->ntb.pdev = sndev->stdev->pdev;
848 	sndev->ntb.topo = NTB_TOPO_SWITCH;
849 	sndev->ntb.ops = &switchtec_ntb_ops;
850 
851 	INIT_WORK(&sndev->link_reinit_work, link_reinit_work);
852 
853 	sndev->self_partition = sndev->stdev->partition;
854 
855 	sndev->mmio_ntb = sndev->stdev->mmio_ntb;
856 
857 	self = sndev->self_partition;
858 	tpart_vec = ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_high);
859 	tpart_vec <<= 32;
860 	tpart_vec |= ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_low);
861 
862 	part_map = ioread64(&sndev->mmio_ntb->ep_map);
863 	part_map &= ~(1 << sndev->self_partition);
864 
865 	if (!ffs(tpart_vec)) {
866 		if (sndev->stdev->partition_count != 2) {
867 			dev_err(&sndev->stdev->dev,
868 				"ntb target partition not defined\n");
869 			return -ENODEV;
870 		}
871 
872 		bit = ffs(part_map);
873 		if (!bit) {
874 			dev_err(&sndev->stdev->dev,
875 				"peer partition is not NT partition\n");
876 			return -ENODEV;
877 		}
878 
879 		sndev->peer_partition = bit - 1;
880 	} else {
881 		if (ffs(tpart_vec) != fls(tpart_vec)) {
882 			dev_err(&sndev->stdev->dev,
883 				"ntb driver only supports 1 pair of 1-1 ntb mapping\n");
884 			return -ENODEV;
885 		}
886 
887 		sndev->peer_partition = ffs(tpart_vec) - 1;
888 		if (!(part_map && (1 << sndev->peer_partition))) {
889 			dev_err(&sndev->stdev->dev,
890 				"ntb target partition is not NT partition\n");
891 			return -ENODEV;
892 		}
893 	}
894 
895 	dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d\n",
896 		sndev->self_partition, sndev->stdev->partition_count);
897 
898 	sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb +
899 		SWITCHTEC_NTB_REG_CTRL_OFFSET;
900 	sndev->mmio_dbmsg = (void * __iomem)sndev->mmio_ntb +
901 		SWITCHTEC_NTB_REG_DBMSG_OFFSET;
902 
903 	sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition];
904 	sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition];
905 	sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition];
906 	sndev->mmio_peer_dbmsg = sndev->mmio_self_dbmsg;
907 
908 	return 0;
909 }
910 
911 static int config_rsvd_lut_win(struct switchtec_ntb *sndev,
912 			       struct ntb_ctrl_regs __iomem *ctl,
913 			       int lut_idx, int partition, u64 addr)
914 {
915 	int peer_bar = sndev->peer_direct_mw_to_bar[0];
916 	u32 ctl_val;
917 	int rc;
918 
919 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
920 				   NTB_CTRL_PART_STATUS_LOCKED);
921 	if (rc)
922 		return rc;
923 
924 	ctl_val = ioread32(&ctl->bar_entry[peer_bar].ctl);
925 	ctl_val &= 0xFF;
926 	ctl_val |= NTB_CTRL_BAR_LUT_WIN_EN;
927 	ctl_val |= ilog2(LUT_SIZE) << 8;
928 	ctl_val |= (sndev->nr_lut_mw - 1) << 14;
929 	iowrite32(ctl_val, &ctl->bar_entry[peer_bar].ctl);
930 
931 	iowrite64((NTB_CTRL_LUT_EN | (partition << 1) | addr),
932 		  &ctl->lut_entry[lut_idx]);
933 
934 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
935 				   NTB_CTRL_PART_STATUS_NORMAL);
936 	if (rc) {
937 		u32 bar_error, lut_error;
938 
939 		bar_error = ioread32(&ctl->bar_error);
940 		lut_error = ioread32(&ctl->lut_error);
941 		dev_err(&sndev->stdev->dev,
942 			"Error setting up reserved lut window: %08x / %08x\n",
943 			bar_error, lut_error);
944 		return rc;
945 	}
946 
947 	return 0;
948 }
949 
950 static int config_req_id_table(struct switchtec_ntb *sndev,
951 			       struct ntb_ctrl_regs __iomem *mmio_ctrl,
952 			       int *req_ids, int count)
953 {
954 	int i, rc = 0;
955 	u32 error;
956 	u32 proxy_id;
957 
958 	if (ioread32(&mmio_ctrl->req_id_table_size) < count) {
959 		dev_err(&sndev->stdev->dev,
960 			"Not enough requester IDs available.\n");
961 		return -EFAULT;
962 	}
963 
964 	rc = switchtec_ntb_part_op(sndev, mmio_ctrl,
965 				   NTB_CTRL_PART_OP_LOCK,
966 				   NTB_CTRL_PART_STATUS_LOCKED);
967 	if (rc)
968 		return rc;
969 
970 	iowrite32(NTB_PART_CTRL_ID_PROT_DIS,
971 		  &mmio_ctrl->partition_ctrl);
972 
973 	for (i = 0; i < count; i++) {
974 		iowrite32(req_ids[i] << 16 | NTB_CTRL_REQ_ID_EN,
975 			  &mmio_ctrl->req_id_table[i]);
976 
977 		proxy_id = ioread32(&mmio_ctrl->req_id_table[i]);
978 		dev_dbg(&sndev->stdev->dev,
979 			"Requester ID %02X:%02X.%X -> BB:%02X.%X\n",
980 			req_ids[i] >> 8, (req_ids[i] >> 3) & 0x1F,
981 			req_ids[i] & 0x7, (proxy_id >> 4) & 0x1F,
982 			(proxy_id >> 1) & 0x7);
983 	}
984 
985 	rc = switchtec_ntb_part_op(sndev, mmio_ctrl,
986 				   NTB_CTRL_PART_OP_CFG,
987 				   NTB_CTRL_PART_STATUS_NORMAL);
988 
989 	if (rc == -EIO) {
990 		error = ioread32(&mmio_ctrl->req_id_error);
991 		dev_err(&sndev->stdev->dev,
992 			"Error setting up the requester ID table: %08x\n",
993 			error);
994 	}
995 
996 	return 0;
997 }
998 
999 static int crosslink_setup_mws(struct switchtec_ntb *sndev, int ntb_lut_idx,
1000 			       u64 *mw_addrs, int mw_count)
1001 {
1002 	int rc, i;
1003 	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_self_ctrl;
1004 	u64 addr;
1005 	size_t size, offset;
1006 	int bar;
1007 	int xlate_pos;
1008 	u32 ctl_val;
1009 
1010 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
1011 				   NTB_CTRL_PART_STATUS_LOCKED);
1012 	if (rc)
1013 		return rc;
1014 
1015 	for (i = 0; i < sndev->nr_lut_mw; i++) {
1016 		if (i == ntb_lut_idx)
1017 			continue;
1018 
1019 		addr = mw_addrs[0] + LUT_SIZE * i;
1020 
1021 		iowrite64((NTB_CTRL_LUT_EN | (sndev->peer_partition << 1) |
1022 			   addr),
1023 			  &ctl->lut_entry[i]);
1024 	}
1025 
1026 	sndev->nr_direct_mw = min_t(int, sndev->nr_direct_mw, mw_count);
1027 
1028 	for (i = 0; i < sndev->nr_direct_mw; i++) {
1029 		bar = sndev->direct_mw_to_bar[i];
1030 		offset = (i == 0) ? LUT_SIZE * sndev->nr_lut_mw : 0;
1031 		addr = mw_addrs[i] + offset;
1032 		size = pci_resource_len(sndev->ntb.pdev, bar) - offset;
1033 		xlate_pos = ilog2(size);
1034 
1035 		if (offset && size > offset)
1036 			size = offset;
1037 
1038 		ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
1039 		ctl_val |= NTB_CTRL_BAR_DIR_WIN_EN;
1040 
1041 		iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
1042 		iowrite32(xlate_pos | size, &ctl->bar_entry[bar].win_size);
1043 		iowrite64(sndev->peer_partition | addr,
1044 			  &ctl->bar_entry[bar].xlate_addr);
1045 	}
1046 
1047 	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
1048 				   NTB_CTRL_PART_STATUS_NORMAL);
1049 	if (rc) {
1050 		u32 bar_error, lut_error;
1051 
1052 		bar_error = ioread32(&ctl->bar_error);
1053 		lut_error = ioread32(&ctl->lut_error);
1054 		dev_err(&sndev->stdev->dev,
1055 			"Error setting up cross link windows: %08x / %08x\n",
1056 			bar_error, lut_error);
1057 		return rc;
1058 	}
1059 
1060 	return 0;
1061 }
1062 
1063 static int crosslink_setup_req_ids(struct switchtec_ntb *sndev,
1064 	struct ntb_ctrl_regs __iomem *mmio_ctrl)
1065 {
1066 	int req_ids[16];
1067 	int i;
1068 	u32 proxy_id;
1069 
1070 	for (i = 0; i < ARRAY_SIZE(req_ids); i++) {
1071 		proxy_id = ioread32(&sndev->mmio_self_ctrl->req_id_table[i]);
1072 
1073 		if (!(proxy_id & NTB_CTRL_REQ_ID_EN))
1074 			break;
1075 
1076 		req_ids[i] = ((proxy_id >> 1) & 0xFF);
1077 	}
1078 
1079 	return config_req_id_table(sndev, mmio_ctrl, req_ids, i);
1080 }
1081 
1082 /*
1083  * In crosslink configuration there is a virtual partition in the
1084  * middle of the two switches. The BARs in this partition have to be
1085  * enumerated and assigned addresses.
1086  */
1087 static int crosslink_enum_partition(struct switchtec_ntb *sndev,
1088 				    u64 *bar_addrs)
1089 {
1090 	struct part_cfg_regs __iomem *part_cfg =
1091 		&sndev->stdev->mmio_part_cfg_all[sndev->peer_partition];
1092 	u32 pff = ioread32(&part_cfg->vep_pff_inst_id);
1093 	struct pff_csr_regs __iomem *mmio_pff =
1094 		&sndev->stdev->mmio_pff_csr[pff];
1095 	const u64 bar_space = 0x1000000000LL;
1096 	u64 bar_addr;
1097 	int bar_cnt = 0;
1098 	int i;
1099 
1100 	iowrite16(0x6, &mmio_pff->pcicmd);
1101 
1102 	for (i = 0; i < ARRAY_SIZE(mmio_pff->pci_bar64); i++) {
1103 		iowrite64(bar_space * i, &mmio_pff->pci_bar64[i]);
1104 		bar_addr = ioread64(&mmio_pff->pci_bar64[i]);
1105 		bar_addr &= ~0xf;
1106 
1107 		dev_dbg(&sndev->stdev->dev,
1108 			"Crosslink BAR%d addr: %llx\n",
1109 			i, bar_addr);
1110 
1111 		if (bar_addr != bar_space * i)
1112 			continue;
1113 
1114 		bar_addrs[bar_cnt++] = bar_addr;
1115 	}
1116 
1117 	return bar_cnt;
1118 }
1119 
1120 static int switchtec_ntb_init_crosslink(struct switchtec_ntb *sndev)
1121 {
1122 	int rc;
1123 	int bar = sndev->direct_mw_to_bar[0];
1124 	const int ntb_lut_idx = 1;
1125 	u64 bar_addrs[6];
1126 	u64 addr;
1127 	int offset;
1128 	int bar_cnt;
1129 
1130 	if (!crosslink_is_enabled(sndev))
1131 		return 0;
1132 
1133 	dev_info(&sndev->stdev->dev, "Using crosslink configuration\n");
1134 	sndev->ntb.topo = NTB_TOPO_CROSSLINK;
1135 
1136 	bar_cnt = crosslink_enum_partition(sndev, bar_addrs);
1137 	if (bar_cnt < sndev->nr_direct_mw + 1) {
1138 		dev_err(&sndev->stdev->dev,
1139 			"Error enumerating crosslink partition\n");
1140 		return -EINVAL;
1141 	}
1142 
1143 	addr = (bar_addrs[0] + SWITCHTEC_GAS_NTB_OFFSET +
1144 		SWITCHTEC_NTB_REG_DBMSG_OFFSET +
1145 		sizeof(struct ntb_dbmsg_regs) * sndev->peer_partition);
1146 
1147 	offset = addr & (LUT_SIZE - 1);
1148 	addr -= offset;
1149 
1150 	rc = config_rsvd_lut_win(sndev, sndev->mmio_self_ctrl, ntb_lut_idx,
1151 				 sndev->peer_partition, addr);
1152 	if (rc)
1153 		return rc;
1154 
1155 	rc = crosslink_setup_mws(sndev, ntb_lut_idx, &bar_addrs[1],
1156 				 bar_cnt - 1);
1157 	if (rc)
1158 		return rc;
1159 
1160 	rc = crosslink_setup_req_ids(sndev, sndev->mmio_peer_ctrl);
1161 	if (rc)
1162 		return rc;
1163 
1164 	sndev->mmio_xlink_win = pci_iomap_range(sndev->stdev->pdev, bar,
1165 						LUT_SIZE, LUT_SIZE);
1166 	if (!sndev->mmio_xlink_win) {
1167 		rc = -ENOMEM;
1168 		return rc;
1169 	}
1170 
1171 	sndev->mmio_peer_dbmsg = sndev->mmio_xlink_win + offset;
1172 	sndev->nr_rsvd_luts++;
1173 
1174 	crosslink_init_dbmsgs(sndev);
1175 
1176 	return 0;
1177 }
1178 
1179 static void switchtec_ntb_deinit_crosslink(struct switchtec_ntb *sndev)
1180 {
1181 	if (sndev->mmio_xlink_win)
1182 		pci_iounmap(sndev->stdev->pdev, sndev->mmio_xlink_win);
1183 }
1184 
1185 static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
1186 {
1187 	int i;
1188 	int cnt = 0;
1189 
1190 	for (i = 0; i < ARRAY_SIZE(ctrl->bar_entry); i++) {
1191 		u32 r = ioread32(&ctrl->bar_entry[i].ctl);
1192 
1193 		if (r & NTB_CTRL_BAR_VALID)
1194 			map[cnt++] = i;
1195 	}
1196 
1197 	return cnt;
1198 }
1199 
1200 static void switchtec_ntb_init_mw(struct switchtec_ntb *sndev)
1201 {
1202 	sndev->nr_direct_mw = map_bars(sndev->direct_mw_to_bar,
1203 				       sndev->mmio_self_ctrl);
1204 
1205 	sndev->nr_lut_mw = ioread16(&sndev->mmio_self_ctrl->lut_table_entries);
1206 	sndev->nr_lut_mw = rounddown_pow_of_two(sndev->nr_lut_mw);
1207 
1208 	dev_dbg(&sndev->stdev->dev, "MWs: %d direct, %d lut\n",
1209 		sndev->nr_direct_mw, sndev->nr_lut_mw);
1210 
1211 	sndev->peer_nr_direct_mw = map_bars(sndev->peer_direct_mw_to_bar,
1212 					    sndev->mmio_peer_ctrl);
1213 
1214 	sndev->peer_nr_lut_mw =
1215 		ioread16(&sndev->mmio_peer_ctrl->lut_table_entries);
1216 	sndev->peer_nr_lut_mw = rounddown_pow_of_two(sndev->peer_nr_lut_mw);
1217 
1218 	dev_dbg(&sndev->stdev->dev, "Peer MWs: %d direct, %d lut\n",
1219 		sndev->peer_nr_direct_mw, sndev->peer_nr_lut_mw);
1220 
1221 }
1222 
1223 /*
1224  * There are 64 doorbells in the switch hardware but this is
1225  * shared among all partitions. So we must split them in half
1226  * (32 for each partition). However, the message interrupts are
1227  * also shared with the top 4 doorbells so we just limit this to
1228  * 28 doorbells per partition.
1229  *
1230  * In crosslink mode, each side has it's own dbmsg register so
1231  * they can each use all 60 of the available doorbells.
1232  */
1233 static void switchtec_ntb_init_db(struct switchtec_ntb *sndev)
1234 {
1235 	sndev->db_mask = 0x0FFFFFFFFFFFFFFFULL;
1236 
1237 	if (sndev->mmio_peer_dbmsg != sndev->mmio_self_dbmsg) {
1238 		sndev->db_shift = 0;
1239 		sndev->db_peer_shift = 0;
1240 		sndev->db_valid_mask = sndev->db_mask;
1241 	} else if (sndev->self_partition < sndev->peer_partition) {
1242 		sndev->db_shift = 0;
1243 		sndev->db_peer_shift = 32;
1244 		sndev->db_valid_mask = 0x0FFFFFFF;
1245 	} else {
1246 		sndev->db_shift = 32;
1247 		sndev->db_peer_shift = 0;
1248 		sndev->db_valid_mask = 0x0FFFFFFF;
1249 	}
1250 
1251 	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
1252 	iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
1253 		  &sndev->mmio_peer_dbmsg->odb_mask);
1254 
1255 	dev_dbg(&sndev->stdev->dev, "dbs: shift %d/%d, mask %016llx\n",
1256 		sndev->db_shift, sndev->db_peer_shift, sndev->db_valid_mask);
1257 }
1258 
1259 static void switchtec_ntb_init_msgs(struct switchtec_ntb *sndev)
1260 {
1261 	int i;
1262 	u32 msg_map = 0;
1263 
1264 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
1265 		int m = i | sndev->peer_partition << 2;
1266 
1267 		msg_map |= m << i * 8;
1268 	}
1269 
1270 	iowrite32(msg_map, &sndev->mmio_self_dbmsg->msg_map);
1271 
1272 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++)
1273 		iowrite64(NTB_DBMSG_IMSG_STATUS | NTB_DBMSG_IMSG_MASK,
1274 			  &sndev->mmio_self_dbmsg->imsg[i]);
1275 }
1276 
1277 static int
1278 switchtec_ntb_init_req_id_table(struct switchtec_ntb *sndev)
1279 {
1280 	int req_ids[2];
1281 
1282 	/*
1283 	 * Root Complex Requester ID (which is 0:00.0)
1284 	 */
1285 	req_ids[0] = 0;
1286 
1287 	/*
1288 	 * Host Bridge Requester ID (as read from the mmap address)
1289 	 */
1290 	req_ids[1] = ioread16(&sndev->mmio_ntb->requester_id);
1291 
1292 	return config_req_id_table(sndev, sndev->mmio_self_ctrl, req_ids,
1293 				   ARRAY_SIZE(req_ids));
1294 }
1295 
1296 static void switchtec_ntb_init_shared(struct switchtec_ntb *sndev)
1297 {
1298 	int i;
1299 
1300 	memset(sndev->self_shared, 0, LUT_SIZE);
1301 	sndev->self_shared->magic = SWITCHTEC_NTB_MAGIC;
1302 	sndev->self_shared->partition_id = sndev->stdev->partition;
1303 
1304 	for (i = 0; i < sndev->nr_direct_mw; i++) {
1305 		int bar = sndev->direct_mw_to_bar[i];
1306 		resource_size_t sz = pci_resource_len(sndev->stdev->pdev, bar);
1307 
1308 		if (i == 0)
1309 			sz = min_t(resource_size_t, sz,
1310 				   LUT_SIZE * sndev->nr_lut_mw);
1311 
1312 		sndev->self_shared->mw_sizes[i] = sz;
1313 	}
1314 
1315 	for (i = 0; i < sndev->nr_lut_mw; i++) {
1316 		int idx = sndev->nr_direct_mw + i;
1317 
1318 		sndev->self_shared->mw_sizes[idx] = LUT_SIZE;
1319 	}
1320 }
1321 
1322 static int switchtec_ntb_init_shared_mw(struct switchtec_ntb *sndev)
1323 {
1324 	int self_bar = sndev->direct_mw_to_bar[0];
1325 	int rc;
1326 
1327 	sndev->nr_rsvd_luts++;
1328 	sndev->self_shared = dma_zalloc_coherent(&sndev->stdev->pdev->dev,
1329 						 LUT_SIZE,
1330 						 &sndev->self_shared_dma,
1331 						 GFP_KERNEL);
1332 	if (!sndev->self_shared) {
1333 		dev_err(&sndev->stdev->dev,
1334 			"unable to allocate memory for shared mw\n");
1335 		return -ENOMEM;
1336 	}
1337 
1338 	switchtec_ntb_init_shared(sndev);
1339 
1340 	rc = config_rsvd_lut_win(sndev, sndev->mmio_peer_ctrl, 0,
1341 				 sndev->self_partition,
1342 				 sndev->self_shared_dma);
1343 	if (rc)
1344 		goto unalloc_and_exit;
1345 
1346 	sndev->peer_shared = pci_iomap(sndev->stdev->pdev, self_bar, LUT_SIZE);
1347 	if (!sndev->peer_shared) {
1348 		rc = -ENOMEM;
1349 		goto unalloc_and_exit;
1350 	}
1351 
1352 	dev_dbg(&sndev->stdev->dev, "Shared MW Ready\n");
1353 	return 0;
1354 
1355 unalloc_and_exit:
1356 	dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
1357 			  sndev->self_shared, sndev->self_shared_dma);
1358 
1359 	return rc;
1360 }
1361 
1362 static void switchtec_ntb_deinit_shared_mw(struct switchtec_ntb *sndev)
1363 {
1364 	if (sndev->peer_shared)
1365 		pci_iounmap(sndev->stdev->pdev, sndev->peer_shared);
1366 
1367 	if (sndev->self_shared)
1368 		dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
1369 				  sndev->self_shared,
1370 				  sndev->self_shared_dma);
1371 	sndev->nr_rsvd_luts--;
1372 }
1373 
1374 static irqreturn_t switchtec_ntb_doorbell_isr(int irq, void *dev)
1375 {
1376 	struct switchtec_ntb *sndev = dev;
1377 
1378 	dev_dbg(&sndev->stdev->dev, "doorbell\n");
1379 
1380 	ntb_db_event(&sndev->ntb, 0);
1381 
1382 	return IRQ_HANDLED;
1383 }
1384 
1385 static irqreturn_t switchtec_ntb_message_isr(int irq, void *dev)
1386 {
1387 	int i;
1388 	struct switchtec_ntb *sndev = dev;
1389 
1390 	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
1391 		u64 msg = ioread64(&sndev->mmio_self_dbmsg->imsg[i]);
1392 
1393 		if (msg & NTB_DBMSG_IMSG_STATUS) {
1394 			dev_dbg(&sndev->stdev->dev, "message: %d %08x\n",
1395 				i, (u32)msg);
1396 			iowrite8(1, &sndev->mmio_self_dbmsg->imsg[i].status);
1397 
1398 			if (i == LINK_MESSAGE)
1399 				switchtec_ntb_check_link(sndev, msg);
1400 		}
1401 	}
1402 
1403 	return IRQ_HANDLED;
1404 }
1405 
1406 static int switchtec_ntb_init_db_msg_irq(struct switchtec_ntb *sndev)
1407 {
1408 	int i;
1409 	int rc;
1410 	int doorbell_irq = 0;
1411 	int message_irq = 0;
1412 	int event_irq;
1413 	int idb_vecs = sizeof(sndev->mmio_self_dbmsg->idb_vec_map);
1414 
1415 	event_irq = ioread32(&sndev->stdev->mmio_part_cfg->vep_vector_number);
1416 
1417 	while (doorbell_irq == event_irq)
1418 		doorbell_irq++;
1419 	while (message_irq == doorbell_irq ||
1420 	       message_irq == event_irq)
1421 		message_irq++;
1422 
1423 	dev_dbg(&sndev->stdev->dev, "irqs - event: %d, db: %d, msgs: %d\n",
1424 		event_irq, doorbell_irq, message_irq);
1425 
1426 	for (i = 0; i < idb_vecs - 4; i++)
1427 		iowrite8(doorbell_irq,
1428 			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
1429 
1430 	for (; i < idb_vecs; i++)
1431 		iowrite8(message_irq,
1432 			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
1433 
1434 	sndev->doorbell_irq = pci_irq_vector(sndev->stdev->pdev, doorbell_irq);
1435 	sndev->message_irq = pci_irq_vector(sndev->stdev->pdev, message_irq);
1436 
1437 	rc = request_irq(sndev->doorbell_irq,
1438 			 switchtec_ntb_doorbell_isr, 0,
1439 			 "switchtec_ntb_doorbell", sndev);
1440 	if (rc)
1441 		return rc;
1442 
1443 	rc = request_irq(sndev->message_irq,
1444 			 switchtec_ntb_message_isr, 0,
1445 			 "switchtec_ntb_message", sndev);
1446 	if (rc) {
1447 		free_irq(sndev->doorbell_irq, sndev);
1448 		return rc;
1449 	}
1450 
1451 	return 0;
1452 }
1453 
1454 static void switchtec_ntb_deinit_db_msg_irq(struct switchtec_ntb *sndev)
1455 {
1456 	free_irq(sndev->doorbell_irq, sndev);
1457 	free_irq(sndev->message_irq, sndev);
1458 }
1459 
1460 static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev)
1461 {
1462 	dev_info(&sndev->stdev->dev, "peer reinitialized\n");
1463 	switchtec_ntb_deinit_shared_mw(sndev);
1464 	switchtec_ntb_init_mw(sndev);
1465 	return switchtec_ntb_init_shared_mw(sndev);
1466 }
1467 
1468 static int switchtec_ntb_add(struct device *dev,
1469 			     struct class_interface *class_intf)
1470 {
1471 	struct switchtec_dev *stdev = to_stdev(dev);
1472 	struct switchtec_ntb *sndev;
1473 	int rc;
1474 
1475 	stdev->sndev = NULL;
1476 
1477 	if (stdev->pdev->class != MICROSEMI_NTB_CLASSCODE)
1478 		return -ENODEV;
1479 
1480 	sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev));
1481 	if (!sndev)
1482 		return -ENOMEM;
1483 
1484 	sndev->stdev = stdev;
1485 	rc = switchtec_ntb_init_sndev(sndev);
1486 	if (rc)
1487 		goto free_and_exit;
1488 
1489 	switchtec_ntb_init_mw(sndev);
1490 
1491 	rc = switchtec_ntb_init_req_id_table(sndev);
1492 	if (rc)
1493 		goto free_and_exit;
1494 
1495 	rc = switchtec_ntb_init_crosslink(sndev);
1496 	if (rc)
1497 		goto free_and_exit;
1498 
1499 	switchtec_ntb_init_db(sndev);
1500 	switchtec_ntb_init_msgs(sndev);
1501 
1502 	rc = switchtec_ntb_init_shared_mw(sndev);
1503 	if (rc)
1504 		goto deinit_crosslink;
1505 
1506 	rc = switchtec_ntb_init_db_msg_irq(sndev);
1507 	if (rc)
1508 		goto deinit_shared_and_exit;
1509 
1510 	/*
1511 	 * If this host crashed, the other host may think the link is
1512 	 * still up. Tell them to force it down (it will go back up
1513 	 * once we register the ntb device).
1514 	 */
1515 	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_FORCE_DOWN);
1516 
1517 	rc = ntb_register_device(&sndev->ntb);
1518 	if (rc)
1519 		goto deinit_and_exit;
1520 
1521 	stdev->sndev = sndev;
1522 	stdev->link_notifier = switchtec_ntb_link_notification;
1523 	dev_info(dev, "NTB device registered\n");
1524 
1525 	return 0;
1526 
1527 deinit_and_exit:
1528 	switchtec_ntb_deinit_db_msg_irq(sndev);
1529 deinit_shared_and_exit:
1530 	switchtec_ntb_deinit_shared_mw(sndev);
1531 deinit_crosslink:
1532 	switchtec_ntb_deinit_crosslink(sndev);
1533 free_and_exit:
1534 	kfree(sndev);
1535 	dev_err(dev, "failed to register ntb device: %d\n", rc);
1536 	return rc;
1537 }
1538 
1539 void switchtec_ntb_remove(struct device *dev,
1540 			  struct class_interface *class_intf)
1541 {
1542 	struct switchtec_dev *stdev = to_stdev(dev);
1543 	struct switchtec_ntb *sndev = stdev->sndev;
1544 
1545 	if (!sndev)
1546 		return;
1547 
1548 	stdev->link_notifier = NULL;
1549 	stdev->sndev = NULL;
1550 	ntb_unregister_device(&sndev->ntb);
1551 	switchtec_ntb_deinit_db_msg_irq(sndev);
1552 	switchtec_ntb_deinit_shared_mw(sndev);
1553 	switchtec_ntb_deinit_crosslink(sndev);
1554 	kfree(sndev);
1555 	dev_info(dev, "ntb device unregistered\n");
1556 }
1557 
1558 static struct class_interface switchtec_interface  = {
1559 	.add_dev = switchtec_ntb_add,
1560 	.remove_dev = switchtec_ntb_remove,
1561 };
1562 
1563 static int __init switchtec_ntb_init(void)
1564 {
1565 	switchtec_interface.class = switchtec_class;
1566 	return class_interface_register(&switchtec_interface);
1567 }
1568 module_init(switchtec_ntb_init);
1569 
1570 static void __exit switchtec_ntb_exit(void)
1571 {
1572 	class_interface_unregister(&switchtec_interface);
1573 }
1574 module_exit(switchtec_ntb_exit);
1575