1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Microsemi Switchtec(tm) PCIe Management Driver
4 * Copyright (c) 2017, Microsemi Corporation
5 */
6
7#include <linux/interrupt.h>
8#include <linux/io-64-nonatomic-lo-hi.h>
9#include <linux/delay.h>
10#include <linux/kthread.h>
11#include <linux/module.h>
12#include <linux/ntb.h>
13#include <linux/pci.h>
14#include <linux/switchtec.h>
15
16MODULE_DESCRIPTION("Microsemi Switchtec(tm) NTB Driver");
17MODULE_VERSION("0.1");
18MODULE_LICENSE("GPL");
19MODULE_AUTHOR("Microsemi Corporation");
20
21static ulong max_mw_size = SZ_2M;
22module_param(max_mw_size, ulong, 0644);
23MODULE_PARM_DESC(max_mw_size,
24	"Max memory window size reported to the upper layer");
25
26static bool use_lut_mws;
27module_param(use_lut_mws, bool, 0644);
28MODULE_PARM_DESC(use_lut_mws,
29		 "Enable the use of the LUT based memory windows");
30
31#define SWITCHTEC_NTB_MAGIC 0x45CC0001
32#define MAX_MWS     128
33
34struct shared_mw {
35	u32 magic;
36	u32 link_sta;
37	u32 partition_id;
38	u64 mw_sizes[MAX_MWS];
39	u32 spad[128];
40};
41
42#define MAX_DIRECT_MW ARRAY_SIZE(((struct ntb_ctrl_regs *)(0))->bar_entry)
43#define LUT_SIZE SZ_64K
44
45struct switchtec_ntb {
46	struct ntb_dev ntb;
47	struct switchtec_dev *stdev;
48
49	int self_partition;
50	int peer_partition;
51
52	int doorbell_irq;
53	int message_irq;
54
55	struct ntb_info_regs __iomem *mmio_ntb;
56	struct ntb_ctrl_regs __iomem *mmio_ctrl;
57	struct ntb_dbmsg_regs __iomem *mmio_dbmsg;
58	struct ntb_ctrl_regs __iomem *mmio_self_ctrl;
59	struct ntb_ctrl_regs __iomem *mmio_peer_ctrl;
60	struct ntb_dbmsg_regs __iomem *mmio_self_dbmsg;
61	struct ntb_dbmsg_regs __iomem *mmio_peer_dbmsg;
62
63	void __iomem *mmio_xlink_win;
64
65	struct shared_mw *self_shared;
66	struct shared_mw __iomem *peer_shared;
67	dma_addr_t self_shared_dma;
68
69	u64 db_mask;
70	u64 db_valid_mask;
71	int db_shift;
72	int db_peer_shift;
73
74	/* synchronize rmw access of db_mask and hw reg */
75	spinlock_t db_mask_lock;
76
77	int nr_direct_mw;
78	int nr_lut_mw;
79	int nr_rsvd_luts;
80	int direct_mw_to_bar[MAX_DIRECT_MW];
81
82	int peer_nr_direct_mw;
83	int peer_nr_lut_mw;
84	int peer_direct_mw_to_bar[MAX_DIRECT_MW];
85
86	bool link_is_up;
87	enum ntb_speed link_speed;
88	enum ntb_width link_width;
89	struct work_struct check_link_status_work;
90	bool link_force_down;
91};
92
93static struct switchtec_ntb *ntb_sndev(struct ntb_dev *ntb)
94{
95	return container_of(ntb, struct switchtec_ntb, ntb);
96}
97
98static int switchtec_ntb_part_op(struct switchtec_ntb *sndev,
99				 struct ntb_ctrl_regs __iomem *ctl,
100				 u32 op, int wait_status)
101{
102	static const char * const op_text[] = {
103		[NTB_CTRL_PART_OP_LOCK] = "lock",
104		[NTB_CTRL_PART_OP_CFG] = "configure",
105		[NTB_CTRL_PART_OP_RESET] = "reset",
106	};
107
108	int i;
109	u32 ps;
110	int status;
111
112	switch (op) {
113	case NTB_CTRL_PART_OP_LOCK:
114		status = NTB_CTRL_PART_STATUS_LOCKING;
115		break;
116	case NTB_CTRL_PART_OP_CFG:
117		status = NTB_CTRL_PART_STATUS_CONFIGURING;
118		break;
119	case NTB_CTRL_PART_OP_RESET:
120		status = NTB_CTRL_PART_STATUS_RESETTING;
121		break;
122	default:
123		return -EINVAL;
124	}
125
126	iowrite32(op, &ctl->partition_op);
127
128	for (i = 0; i < 1000; i++) {
129		if (msleep_interruptible(50) != 0) {
130			iowrite32(NTB_CTRL_PART_OP_RESET, &ctl->partition_op);
131			return -EINTR;
132		}
133
134		ps = ioread32(&ctl->partition_status) & 0xFFFF;
135
136		if (ps != status)
137			break;
138	}
139
140	if (ps == wait_status)
141		return 0;
142
143	if (ps == status) {
144		dev_err(&sndev->stdev->dev,
145			"Timed out while performing %s (%d). (%08x)\n",
146			op_text[op], op,
147			ioread32(&ctl->partition_status));
148
149		return -ETIMEDOUT;
150	}
151
152	return -EIO;
153}
154
155static int switchtec_ntb_send_msg(struct switchtec_ntb *sndev, int idx,
156				  u32 val)
157{
158	if (idx < 0 || idx >= ARRAY_SIZE(sndev->mmio_peer_dbmsg->omsg))
159		return -EINVAL;
160
161	iowrite32(val, &sndev->mmio_peer_dbmsg->omsg[idx].msg);
162
163	return 0;
164}
165
166static int switchtec_ntb_mw_count(struct ntb_dev *ntb, int pidx)
167{
168	struct switchtec_ntb *sndev = ntb_sndev(ntb);
169	int nr_direct_mw = sndev->peer_nr_direct_mw;
170	int nr_lut_mw = sndev->peer_nr_lut_mw - sndev->nr_rsvd_luts;
171
172	if (pidx != NTB_DEF_PEER_IDX)
173		return -EINVAL;
174
175	if (!use_lut_mws)
176		nr_lut_mw = 0;
177
178	return nr_direct_mw + nr_lut_mw;
179}
180
181static int lut_index(struct switchtec_ntb *sndev, int mw_idx)
182{
183	return mw_idx - sndev->nr_direct_mw + sndev->nr_rsvd_luts;
184}
185
186static int peer_lut_index(struct switchtec_ntb *sndev, int mw_idx)
187{
188	return mw_idx - sndev->peer_nr_direct_mw + sndev->nr_rsvd_luts;
189}
190
191static int switchtec_ntb_mw_get_align(struct ntb_dev *ntb, int pidx,
192				      int widx, resource_size_t *addr_align,
193				      resource_size_t *size_align,
194				      resource_size_t *size_max)
195{
196	struct switchtec_ntb *sndev = ntb_sndev(ntb);
197	int lut;
198	resource_size_t size;
199
200	if (pidx != NTB_DEF_PEER_IDX)
201		return -EINVAL;
202
203	lut = widx >= sndev->peer_nr_direct_mw;
204	size = ioread64(&sndev->peer_shared->mw_sizes[widx]);
205
206	if (size == 0)
207		return -EINVAL;
208
209	if (addr_align)
210		*addr_align = lut ? size : SZ_4K;
211
212	if (size_align)
213		*size_align = lut ? size : SZ_4K;
214
215	if (size_max)
216		*size_max = size;
217
218	return 0;
219}
220
221static void switchtec_ntb_mw_clr_direct(struct switchtec_ntb *sndev, int idx)
222{
223	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
224	int bar = sndev->peer_direct_mw_to_bar[idx];
225	u32 ctl_val;
226
227	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
228	ctl_val &= ~NTB_CTRL_BAR_DIR_WIN_EN;
229	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
230	iowrite32(0, &ctl->bar_entry[bar].win_size);
231	iowrite32(0, &ctl->bar_ext_entry[bar].win_size);
232	iowrite64(sndev->self_partition, &ctl->bar_entry[bar].xlate_addr);
233}
234
235static void switchtec_ntb_mw_clr_lut(struct switchtec_ntb *sndev, int idx)
236{
237	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
238
239	iowrite64(0, &ctl->lut_entry[peer_lut_index(sndev, idx)]);
240}
241
242static void switchtec_ntb_mw_set_direct(struct switchtec_ntb *sndev, int idx,
243					dma_addr_t addr, resource_size_t size)
244{
245	int xlate_pos = ilog2(size);
246	int bar = sndev->peer_direct_mw_to_bar[idx];
247	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
248	u32 ctl_val;
249
250	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
251	ctl_val |= NTB_CTRL_BAR_DIR_WIN_EN;
252
253	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
254	iowrite32(xlate_pos | (lower_32_bits(size) & 0xFFFFF000),
255		  &ctl->bar_entry[bar].win_size);
256	iowrite32(upper_32_bits(size), &ctl->bar_ext_entry[bar].win_size);
257	iowrite64(sndev->self_partition | addr,
258		  &ctl->bar_entry[bar].xlate_addr);
259}
260
261static void switchtec_ntb_mw_set_lut(struct switchtec_ntb *sndev, int idx,
262				     dma_addr_t addr, resource_size_t size)
263{
264	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
265
266	iowrite64((NTB_CTRL_LUT_EN | (sndev->self_partition << 1) | addr),
267		  &ctl->lut_entry[peer_lut_index(sndev, idx)]);
268}
269
270static int switchtec_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx,
271				      dma_addr_t addr, resource_size_t size)
272{
273	struct switchtec_ntb *sndev = ntb_sndev(ntb);
274	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
275	int xlate_pos = ilog2(size);
276	int nr_direct_mw = sndev->peer_nr_direct_mw;
277	int rc;
278
279	if (pidx != NTB_DEF_PEER_IDX)
280		return -EINVAL;
281
282	dev_dbg(&sndev->stdev->dev, "MW %d: part %d addr %pad size %pap\n",
283		widx, pidx, &addr, &size);
284
285	if (widx >= switchtec_ntb_mw_count(ntb, pidx))
286		return -EINVAL;
287
288	if (size != 0 && xlate_pos < 12)
289		return -EINVAL;
290
291	if (!IS_ALIGNED(addr, BIT_ULL(xlate_pos))) {
292		/*
293		 * In certain circumstances we can get a buffer that is
294		 * not aligned to its size. (Most of the time
295		 * dma_alloc_coherent ensures this). This can happen when
296		 * using large buffers allocated by the CMA
297		 * (see CMA_CONFIG_ALIGNMENT)
298		 */
299		dev_err(&sndev->stdev->dev,
300			"ERROR: Memory window address is not aligned to it's size!\n");
301		return -EINVAL;
302	}
303
304	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
305				   NTB_CTRL_PART_STATUS_LOCKED);
306	if (rc)
307		return rc;
308
309	if (size == 0) {
310		if (widx < nr_direct_mw)
311			switchtec_ntb_mw_clr_direct(sndev, widx);
312		else
313			switchtec_ntb_mw_clr_lut(sndev, widx);
314	} else {
315		if (widx < nr_direct_mw)
316			switchtec_ntb_mw_set_direct(sndev, widx, addr, size);
317		else
318			switchtec_ntb_mw_set_lut(sndev, widx, addr, size);
319	}
320
321	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
322				   NTB_CTRL_PART_STATUS_NORMAL);
323
324	if (rc == -EIO) {
325		dev_err(&sndev->stdev->dev,
326			"Hardware reported an error configuring mw %d: %08x\n",
327			widx, ioread32(&ctl->bar_error));
328
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
334		switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
335				      NTB_CTRL_PART_STATUS_NORMAL);
336	}
337
338	return rc;
339}
340
341static int switchtec_ntb_peer_mw_count(struct ntb_dev *ntb)
342{
343	struct switchtec_ntb *sndev = ntb_sndev(ntb);
344	int nr_lut_mw = sndev->nr_lut_mw - sndev->nr_rsvd_luts;
345
346	return sndev->nr_direct_mw + (use_lut_mws ? nr_lut_mw : 0);
347}
348
349static int switchtec_ntb_direct_get_addr(struct switchtec_ntb *sndev,
350					 int idx, phys_addr_t *base,
351					 resource_size_t *size)
352{
353	int bar = sndev->direct_mw_to_bar[idx];
354	size_t offset = 0;
355
356	if (bar < 0)
357		return -EINVAL;
358
359	if (idx == 0) {
360		/*
361		 * This is the direct BAR shared with the LUTs
362		 * which means the actual window will be offset
363		 * by the size of all the LUT entries.
364		 */
365
366		offset = LUT_SIZE * sndev->nr_lut_mw;
367	}
368
369	if (base)
370		*base = pci_resource_start(sndev->ntb.pdev, bar) + offset;
371
372	if (size) {
373		*size = pci_resource_len(sndev->ntb.pdev, bar) - offset;
374		if (offset && *size > offset)
375			*size = offset;
376
377		if (*size > max_mw_size)
378			*size = max_mw_size;
379	}
380
381	return 0;
382}
383
384static int switchtec_ntb_lut_get_addr(struct switchtec_ntb *sndev,
385				      int idx, phys_addr_t *base,
386				      resource_size_t *size)
387{
388	int bar = sndev->direct_mw_to_bar[0];
389	int offset;
390
391	offset = LUT_SIZE * lut_index(sndev, idx);
392
393	if (base)
394		*base = pci_resource_start(sndev->ntb.pdev, bar) + offset;
395
396	if (size)
397		*size = LUT_SIZE;
398
399	return 0;
400}
401
402static int switchtec_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
403					  phys_addr_t *base,
404					  resource_size_t *size)
405{
406	struct switchtec_ntb *sndev = ntb_sndev(ntb);
407
408	if (idx < sndev->nr_direct_mw)
409		return switchtec_ntb_direct_get_addr(sndev, idx, base, size);
410	else if (idx < switchtec_ntb_peer_mw_count(ntb))
411		return switchtec_ntb_lut_get_addr(sndev, idx, base, size);
412	else
413		return -EINVAL;
414}
415
416static void switchtec_ntb_part_link_speed(struct switchtec_ntb *sndev,
417					  int partition,
418					  enum ntb_speed *speed,
419					  enum ntb_width *width)
420{
421	struct switchtec_dev *stdev = sndev->stdev;
422
423	u32 pff = ioread32(&stdev->mmio_part_cfg[partition].vep_pff_inst_id);
424	u32 linksta = ioread32(&stdev->mmio_pff_csr[pff].pci_cap_region[13]);
425
426	if (speed)
427		*speed = (linksta >> 16) & 0xF;
428
429	if (width)
430		*width = (linksta >> 20) & 0x3F;
431}
432
433static void switchtec_ntb_set_link_speed(struct switchtec_ntb *sndev)
434{
435	enum ntb_speed self_speed, peer_speed;
436	enum ntb_width self_width, peer_width;
437
438	if (!sndev->link_is_up) {
439		sndev->link_speed = NTB_SPEED_NONE;
440		sndev->link_width = NTB_WIDTH_NONE;
441		return;
442	}
443
444	switchtec_ntb_part_link_speed(sndev, sndev->self_partition,
445				      &self_speed, &self_width);
446	switchtec_ntb_part_link_speed(sndev, sndev->peer_partition,
447				      &peer_speed, &peer_width);
448
449	sndev->link_speed = min(self_speed, peer_speed);
450	sndev->link_width = min(self_width, peer_width);
451}
452
453static int crosslink_is_enabled(struct switchtec_ntb *sndev)
454{
455	struct ntb_info_regs __iomem *inf = sndev->mmio_ntb;
456
457	return ioread8(&inf->ntp_info[sndev->peer_partition].xlink_enabled);
458}
459
460static void crosslink_init_dbmsgs(struct switchtec_ntb *sndev)
461{
462	int i;
463	u32 msg_map = 0;
464
465	if (!crosslink_is_enabled(sndev))
466		return;
467
468	for (i = 0; i < ARRAY_SIZE(sndev->mmio_peer_dbmsg->imsg); i++) {
469		int m = i | sndev->self_partition << 2;
470
471		msg_map |= m << i * 8;
472	}
473
474	iowrite32(msg_map, &sndev->mmio_peer_dbmsg->msg_map);
475	iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
476		  &sndev->mmio_peer_dbmsg->odb_mask);
477}
478
479enum switchtec_msg {
480	LINK_MESSAGE = 0,
481	MSG_LINK_UP = 1,
482	MSG_LINK_DOWN = 2,
483	MSG_CHECK_LINK = 3,
484	MSG_LINK_FORCE_DOWN = 4,
485};
486
487static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev);
488
489static void switchtec_ntb_link_status_update(struct switchtec_ntb *sndev)
490{
491	int link_sta;
492	int old = sndev->link_is_up;
493
494	link_sta = sndev->self_shared->link_sta;
495	if (link_sta) {
496		u64 peer = ioread64(&sndev->peer_shared->magic);
497
498		if ((peer & 0xFFFFFFFF) == SWITCHTEC_NTB_MAGIC)
499			link_sta = peer >> 32;
500		else
501			link_sta = 0;
502	}
503
504	sndev->link_is_up = link_sta;
505	switchtec_ntb_set_link_speed(sndev);
506
507	if (link_sta != old) {
508		switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_CHECK_LINK);
509		ntb_link_event(&sndev->ntb);
510		dev_info(&sndev->stdev->dev, "ntb link %s\n",
511			 link_sta ? "up" : "down");
512
513		if (link_sta)
514			crosslink_init_dbmsgs(sndev);
515	}
516}
517
518static void check_link_status_work(struct work_struct *work)
519{
520	struct switchtec_ntb *sndev;
521
522	sndev = container_of(work, struct switchtec_ntb,
523			     check_link_status_work);
524
525	if (sndev->link_force_down) {
526		sndev->link_force_down = false;
527		switchtec_ntb_reinit_peer(sndev);
528
529		if (sndev->link_is_up) {
530			sndev->link_is_up = 0;
531			ntb_link_event(&sndev->ntb);
532			dev_info(&sndev->stdev->dev, "ntb link forced down\n");
533		}
534
535		return;
536	}
537
538	switchtec_ntb_link_status_update(sndev);
539}
540
541static void switchtec_ntb_check_link(struct switchtec_ntb *sndev,
542				      enum switchtec_msg msg)
543{
544	if (msg == MSG_LINK_FORCE_DOWN)
545		sndev->link_force_down = true;
546
547	schedule_work(&sndev->check_link_status_work);
548}
549
550static void switchtec_ntb_link_notification(struct switchtec_dev *stdev)
551{
552	struct switchtec_ntb *sndev = stdev->sndev;
553
554	switchtec_ntb_check_link(sndev, MSG_CHECK_LINK);
555}
556
557static u64 switchtec_ntb_link_is_up(struct ntb_dev *ntb,
558				    enum ntb_speed *speed,
559				    enum ntb_width *width)
560{
561	struct switchtec_ntb *sndev = ntb_sndev(ntb);
562
563	if (speed)
564		*speed = sndev->link_speed;
565	if (width)
566		*width = sndev->link_width;
567
568	return sndev->link_is_up;
569}
570
571static int switchtec_ntb_link_enable(struct ntb_dev *ntb,
572				     enum ntb_speed max_speed,
573				     enum ntb_width max_width)
574{
575	struct switchtec_ntb *sndev = ntb_sndev(ntb);
576
577	dev_dbg(&sndev->stdev->dev, "enabling link\n");
578
579	sndev->self_shared->link_sta = 1;
580	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_UP);
581
582	switchtec_ntb_link_status_update(sndev);
583
584	return 0;
585}
586
587static int switchtec_ntb_link_disable(struct ntb_dev *ntb)
588{
589	struct switchtec_ntb *sndev = ntb_sndev(ntb);
590
591	dev_dbg(&sndev->stdev->dev, "disabling link\n");
592
593	sndev->self_shared->link_sta = 0;
594	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_DOWN);
595
596	switchtec_ntb_link_status_update(sndev);
597
598	return 0;
599}
600
601static u64 switchtec_ntb_db_valid_mask(struct ntb_dev *ntb)
602{
603	struct switchtec_ntb *sndev = ntb_sndev(ntb);
604
605	return sndev->db_valid_mask;
606}
607
608static int switchtec_ntb_db_vector_count(struct ntb_dev *ntb)
609{
610	return 1;
611}
612
613static u64 switchtec_ntb_db_vector_mask(struct ntb_dev *ntb, int db_vector)
614{
615	struct switchtec_ntb *sndev = ntb_sndev(ntb);
616
617	if (db_vector < 0 || db_vector > 1)
618		return 0;
619
620	return sndev->db_valid_mask;
621}
622
623static u64 switchtec_ntb_db_read(struct ntb_dev *ntb)
624{
625	u64 ret;
626	struct switchtec_ntb *sndev = ntb_sndev(ntb);
627
628	ret = ioread64(&sndev->mmio_self_dbmsg->idb) >> sndev->db_shift;
629
630	return ret & sndev->db_valid_mask;
631}
632
633static int switchtec_ntb_db_clear(struct ntb_dev *ntb, u64 db_bits)
634{
635	struct switchtec_ntb *sndev = ntb_sndev(ntb);
636
637	iowrite64(db_bits << sndev->db_shift, &sndev->mmio_self_dbmsg->idb);
638
639	return 0;
640}
641
642static int switchtec_ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
643{
644	unsigned long irqflags;
645	struct switchtec_ntb *sndev = ntb_sndev(ntb);
646
647	if (db_bits & ~sndev->db_valid_mask)
648		return -EINVAL;
649
650	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
651
652	sndev->db_mask |= db_bits << sndev->db_shift;
653	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
654
655	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
656
657	return 0;
658}
659
660static int switchtec_ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
661{
662	unsigned long irqflags;
663	struct switchtec_ntb *sndev = ntb_sndev(ntb);
664
665	if (db_bits & ~sndev->db_valid_mask)
666		return -EINVAL;
667
668	spin_lock_irqsave(&sndev->db_mask_lock, irqflags);
669
670	sndev->db_mask &= ~(db_bits << sndev->db_shift);
671	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
672
673	spin_unlock_irqrestore(&sndev->db_mask_lock, irqflags);
674
675	return 0;
676}
677
678static u64 switchtec_ntb_db_read_mask(struct ntb_dev *ntb)
679{
680	struct switchtec_ntb *sndev = ntb_sndev(ntb);
681
682	return (sndev->db_mask >> sndev->db_shift) & sndev->db_valid_mask;
683}
684
685static int switchtec_ntb_peer_db_addr(struct ntb_dev *ntb,
686				      phys_addr_t *db_addr,
687				      resource_size_t *db_size,
688				      u64 *db_data,
689				      int db_bit)
690{
691	struct switchtec_ntb *sndev = ntb_sndev(ntb);
692	unsigned long offset;
693
694	if (unlikely(db_bit >= BITS_PER_LONG_LONG))
695		return -EINVAL;
696
697	offset = (unsigned long)sndev->mmio_peer_dbmsg->odb -
698		(unsigned long)sndev->stdev->mmio;
699
700	offset += sndev->db_shift / 8;
701
702	if (db_addr)
703		*db_addr = pci_resource_start(ntb->pdev, 0) + offset;
704	if (db_size)
705		*db_size = sizeof(u32);
706	if (db_data)
707		*db_data = BIT_ULL(db_bit) << sndev->db_peer_shift;
708
709	return 0;
710}
711
712static int switchtec_ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
713{
714	struct switchtec_ntb *sndev = ntb_sndev(ntb);
715
716	iowrite64(db_bits << sndev->db_peer_shift,
717		  &sndev->mmio_peer_dbmsg->odb);
718
719	return 0;
720}
721
722static int switchtec_ntb_spad_count(struct ntb_dev *ntb)
723{
724	struct switchtec_ntb *sndev = ntb_sndev(ntb);
725
726	return ARRAY_SIZE(sndev->self_shared->spad);
727}
728
729static u32 switchtec_ntb_spad_read(struct ntb_dev *ntb, int idx)
730{
731	struct switchtec_ntb *sndev = ntb_sndev(ntb);
732
733	if (idx < 0 || idx >= ARRAY_SIZE(sndev->self_shared->spad))
734		return 0;
735
736	if (!sndev->self_shared)
737		return 0;
738
739	return sndev->self_shared->spad[idx];
740}
741
742static int switchtec_ntb_spad_write(struct ntb_dev *ntb, int idx, u32 val)
743{
744	struct switchtec_ntb *sndev = ntb_sndev(ntb);
745
746	if (idx < 0 || idx >= ARRAY_SIZE(sndev->self_shared->spad))
747		return -EINVAL;
748
749	if (!sndev->self_shared)
750		return -EIO;
751
752	sndev->self_shared->spad[idx] = val;
753
754	return 0;
755}
756
757static u32 switchtec_ntb_peer_spad_read(struct ntb_dev *ntb, int pidx,
758					int sidx)
759{
760	struct switchtec_ntb *sndev = ntb_sndev(ntb);
761
762	if (pidx != NTB_DEF_PEER_IDX)
763		return -EINVAL;
764
765	if (sidx < 0 || sidx >= ARRAY_SIZE(sndev->peer_shared->spad))
766		return 0;
767
768	if (!sndev->peer_shared)
769		return 0;
770
771	return ioread32(&sndev->peer_shared->spad[sidx]);
772}
773
774static int switchtec_ntb_peer_spad_write(struct ntb_dev *ntb, int pidx,
775					 int sidx, u32 val)
776{
777	struct switchtec_ntb *sndev = ntb_sndev(ntb);
778
779	if (pidx != NTB_DEF_PEER_IDX)
780		return -EINVAL;
781
782	if (sidx < 0 || sidx >= ARRAY_SIZE(sndev->peer_shared->spad))
783		return -EINVAL;
784
785	if (!sndev->peer_shared)
786		return -EIO;
787
788	iowrite32(val, &sndev->peer_shared->spad[sidx]);
789
790	return 0;
791}
792
793static int switchtec_ntb_peer_spad_addr(struct ntb_dev *ntb, int pidx,
794					int sidx, phys_addr_t *spad_addr)
795{
796	struct switchtec_ntb *sndev = ntb_sndev(ntb);
797	unsigned long offset;
798
799	if (pidx != NTB_DEF_PEER_IDX)
800		return -EINVAL;
801
802	offset = (unsigned long)&sndev->peer_shared->spad[sidx] -
803		(unsigned long)sndev->stdev->mmio;
804
805	if (spad_addr)
806		*spad_addr = pci_resource_start(ntb->pdev, 0) + offset;
807
808	return 0;
809}
810
811static const struct ntb_dev_ops switchtec_ntb_ops = {
812	.mw_count		= switchtec_ntb_mw_count,
813	.mw_get_align		= switchtec_ntb_mw_get_align,
814	.mw_set_trans		= switchtec_ntb_mw_set_trans,
815	.peer_mw_count		= switchtec_ntb_peer_mw_count,
816	.peer_mw_get_addr	= switchtec_ntb_peer_mw_get_addr,
817	.link_is_up		= switchtec_ntb_link_is_up,
818	.link_enable		= switchtec_ntb_link_enable,
819	.link_disable		= switchtec_ntb_link_disable,
820	.db_valid_mask		= switchtec_ntb_db_valid_mask,
821	.db_vector_count	= switchtec_ntb_db_vector_count,
822	.db_vector_mask		= switchtec_ntb_db_vector_mask,
823	.db_read		= switchtec_ntb_db_read,
824	.db_clear		= switchtec_ntb_db_clear,
825	.db_set_mask		= switchtec_ntb_db_set_mask,
826	.db_clear_mask		= switchtec_ntb_db_clear_mask,
827	.db_read_mask		= switchtec_ntb_db_read_mask,
828	.peer_db_addr		= switchtec_ntb_peer_db_addr,
829	.peer_db_set		= switchtec_ntb_peer_db_set,
830	.spad_count		= switchtec_ntb_spad_count,
831	.spad_read		= switchtec_ntb_spad_read,
832	.spad_write		= switchtec_ntb_spad_write,
833	.peer_spad_read		= switchtec_ntb_peer_spad_read,
834	.peer_spad_write	= switchtec_ntb_peer_spad_write,
835	.peer_spad_addr		= switchtec_ntb_peer_spad_addr,
836};
837
838static int switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
839{
840	u64 tpart_vec;
841	int self;
842	u64 part_map;
843	int bit;
844
845	sndev->ntb.pdev = sndev->stdev->pdev;
846	sndev->ntb.topo = NTB_TOPO_SWITCH;
847	sndev->ntb.ops = &switchtec_ntb_ops;
848
849	INIT_WORK(&sndev->check_link_status_work, check_link_status_work);
850	sndev->link_force_down = false;
851
852	sndev->self_partition = sndev->stdev->partition;
853
854	sndev->mmio_ntb = sndev->stdev->mmio_ntb;
855
856	self = sndev->self_partition;
857	tpart_vec = ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_high);
858	tpart_vec <<= 32;
859	tpart_vec |= ioread32(&sndev->mmio_ntb->ntp_info[self].target_part_low);
860
861	part_map = ioread64(&sndev->mmio_ntb->ep_map);
862	part_map &= ~(1 << sndev->self_partition);
863
864	if (!ffs(tpart_vec)) {
865		if (sndev->stdev->partition_count != 2) {
866			dev_err(&sndev->stdev->dev,
867				"ntb target partition not defined\n");
868			return -ENODEV;
869		}
870
871		bit = ffs(part_map);
872		if (!bit) {
873			dev_err(&sndev->stdev->dev,
874				"peer partition is not NT partition\n");
875			return -ENODEV;
876		}
877
878		sndev->peer_partition = bit - 1;
879	} else {
880		if (ffs(tpart_vec) != fls(tpart_vec)) {
881			dev_err(&sndev->stdev->dev,
882				"ntb driver only supports 1 pair of 1-1 ntb mapping\n");
883			return -ENODEV;
884		}
885
886		sndev->peer_partition = ffs(tpart_vec) - 1;
887		if (!(part_map & (1ULL << sndev->peer_partition))) {
888			dev_err(&sndev->stdev->dev,
889				"ntb target partition is not NT partition\n");
890			return -ENODEV;
891		}
892	}
893
894	dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d\n",
895		sndev->self_partition, sndev->stdev->partition_count);
896
897	sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb +
898		SWITCHTEC_NTB_REG_CTRL_OFFSET;
899	sndev->mmio_dbmsg = (void * __iomem)sndev->mmio_ntb +
900		SWITCHTEC_NTB_REG_DBMSG_OFFSET;
901
902	sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition];
903	sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition];
904	sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition];
905	sndev->mmio_peer_dbmsg = sndev->mmio_self_dbmsg;
906
907	return 0;
908}
909
910static int config_rsvd_lut_win(struct switchtec_ntb *sndev,
911			       struct ntb_ctrl_regs __iomem *ctl,
912			       int lut_idx, int partition, u64 addr)
913{
914	int peer_bar = sndev->peer_direct_mw_to_bar[0];
915	u32 ctl_val;
916	int rc;
917
918	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
919				   NTB_CTRL_PART_STATUS_LOCKED);
920	if (rc)
921		return rc;
922
923	ctl_val = ioread32(&ctl->bar_entry[peer_bar].ctl);
924	ctl_val &= 0xFF;
925	ctl_val |= NTB_CTRL_BAR_LUT_WIN_EN;
926	ctl_val |= ilog2(LUT_SIZE) << 8;
927	ctl_val |= (sndev->nr_lut_mw - 1) << 14;
928	iowrite32(ctl_val, &ctl->bar_entry[peer_bar].ctl);
929
930	iowrite64((NTB_CTRL_LUT_EN | (partition << 1) | addr),
931		  &ctl->lut_entry[lut_idx]);
932
933	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
934				   NTB_CTRL_PART_STATUS_NORMAL);
935	if (rc) {
936		u32 bar_error, lut_error;
937
938		bar_error = ioread32(&ctl->bar_error);
939		lut_error = ioread32(&ctl->lut_error);
940		dev_err(&sndev->stdev->dev,
941			"Error setting up reserved lut window: %08x / %08x\n",
942			bar_error, lut_error);
943		return rc;
944	}
945
946	return 0;
947}
948
949static int config_req_id_table(struct switchtec_ntb *sndev,
950			       struct ntb_ctrl_regs __iomem *mmio_ctrl,
951			       int *req_ids, int count)
952{
953	int i, rc = 0;
954	u32 error;
955	u32 proxy_id;
956
957	if (ioread32(&mmio_ctrl->req_id_table_size) < count) {
958		dev_err(&sndev->stdev->dev,
959			"Not enough requester IDs available.\n");
960		return -EFAULT;
961	}
962
963	rc = switchtec_ntb_part_op(sndev, mmio_ctrl,
964				   NTB_CTRL_PART_OP_LOCK,
965				   NTB_CTRL_PART_STATUS_LOCKED);
966	if (rc)
967		return rc;
968
969	iowrite32(NTB_PART_CTRL_ID_PROT_DIS,
970		  &mmio_ctrl->partition_ctrl);
971
972	for (i = 0; i < count; i++) {
973		iowrite32(req_ids[i] << 16 | NTB_CTRL_REQ_ID_EN,
974			  &mmio_ctrl->req_id_table[i]);
975
976		proxy_id = ioread32(&mmio_ctrl->req_id_table[i]);
977		dev_dbg(&sndev->stdev->dev,
978			"Requester ID %02X:%02X.%X -> BB:%02X.%X\n",
979			req_ids[i] >> 8, (req_ids[i] >> 3) & 0x1F,
980			req_ids[i] & 0x7, (proxy_id >> 4) & 0x1F,
981			(proxy_id >> 1) & 0x7);
982	}
983
984	rc = switchtec_ntb_part_op(sndev, mmio_ctrl,
985				   NTB_CTRL_PART_OP_CFG,
986				   NTB_CTRL_PART_STATUS_NORMAL);
987
988	if (rc == -EIO) {
989		error = ioread32(&mmio_ctrl->req_id_error);
990		dev_err(&sndev->stdev->dev,
991			"Error setting up the requester ID table: %08x\n",
992			error);
993	}
994
995	return 0;
996}
997
998static int crosslink_setup_mws(struct switchtec_ntb *sndev, int ntb_lut_idx,
999			       u64 *mw_addrs, int mw_count)
1000{
1001	int rc, i;
1002	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_self_ctrl;
1003	u64 addr;
1004	size_t size, offset;
1005	int bar;
1006	int xlate_pos;
1007	u32 ctl_val;
1008
1009	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
1010				   NTB_CTRL_PART_STATUS_LOCKED);
1011	if (rc)
1012		return rc;
1013
1014	for (i = 0; i < sndev->nr_lut_mw; i++) {
1015		if (i == ntb_lut_idx)
1016			continue;
1017
1018		addr = mw_addrs[0] + LUT_SIZE * i;
1019
1020		iowrite64((NTB_CTRL_LUT_EN | (sndev->peer_partition << 1) |
1021			   addr),
1022			  &ctl->lut_entry[i]);
1023	}
1024
1025	sndev->nr_direct_mw = min_t(int, sndev->nr_direct_mw, mw_count);
1026
1027	for (i = 0; i < sndev->nr_direct_mw; i++) {
1028		bar = sndev->direct_mw_to_bar[i];
1029		offset = (i == 0) ? LUT_SIZE * sndev->nr_lut_mw : 0;
1030		addr = mw_addrs[i] + offset;
1031		size = pci_resource_len(sndev->ntb.pdev, bar) - offset;
1032		xlate_pos = ilog2(size);
1033
1034		if (offset && size > offset)
1035			size = offset;
1036
1037		ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
1038		ctl_val |= NTB_CTRL_BAR_DIR_WIN_EN;
1039
1040		iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
1041		iowrite32(xlate_pos | (lower_32_bits(size) & 0xFFFFF000),
1042			  &ctl->bar_entry[bar].win_size);
1043		iowrite32(upper_32_bits(size), &ctl->bar_ext_entry[bar].win_size);
1044		iowrite64(sndev->peer_partition | addr,
1045			  &ctl->bar_entry[bar].xlate_addr);
1046	}
1047
1048	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
1049				   NTB_CTRL_PART_STATUS_NORMAL);
1050	if (rc) {
1051		u32 bar_error, lut_error;
1052
1053		bar_error = ioread32(&ctl->bar_error);
1054		lut_error = ioread32(&ctl->lut_error);
1055		dev_err(&sndev->stdev->dev,
1056			"Error setting up cross link windows: %08x / %08x\n",
1057			bar_error, lut_error);
1058		return rc;
1059	}
1060
1061	return 0;
1062}
1063
1064static int crosslink_setup_req_ids(struct switchtec_ntb *sndev,
1065	struct ntb_ctrl_regs __iomem *mmio_ctrl)
1066{
1067	int req_ids[16];
1068	int i;
1069	u32 proxy_id;
1070
1071	for (i = 0; i < ARRAY_SIZE(req_ids); i++) {
1072		proxy_id = ioread32(&sndev->mmio_self_ctrl->req_id_table[i]);
1073
1074		if (!(proxy_id & NTB_CTRL_REQ_ID_EN))
1075			break;
1076
1077		req_ids[i] = ((proxy_id >> 1) & 0xFF);
1078	}
1079
1080	return config_req_id_table(sndev, mmio_ctrl, req_ids, i);
1081}
1082
1083/*
1084 * In crosslink configuration there is a virtual partition in the
1085 * middle of the two switches. The BARs in this partition have to be
1086 * enumerated and assigned addresses.
1087 */
1088static int crosslink_enum_partition(struct switchtec_ntb *sndev,
1089				    u64 *bar_addrs)
1090{
1091	struct part_cfg_regs __iomem *part_cfg =
1092		&sndev->stdev->mmio_part_cfg_all[sndev->peer_partition];
1093	u32 pff = ioread32(&part_cfg->vep_pff_inst_id);
1094	struct pff_csr_regs __iomem *mmio_pff =
1095		&sndev->stdev->mmio_pff_csr[pff];
1096	const u64 bar_space = 0x1000000000LL;
1097	u64 bar_addr;
1098	int bar_cnt = 0;
1099	int i;
1100
1101	iowrite16(0x6, &mmio_pff->pcicmd);
1102
1103	for (i = 0; i < ARRAY_SIZE(mmio_pff->pci_bar64); i++) {
1104		iowrite64(bar_space * i, &mmio_pff->pci_bar64[i]);
1105		bar_addr = ioread64(&mmio_pff->pci_bar64[i]);
1106		bar_addr &= ~0xf;
1107
1108		dev_dbg(&sndev->stdev->dev,
1109			"Crosslink BAR%d addr: %llx\n",
1110			i*2, bar_addr);
1111
1112		if (bar_addr != bar_space * i)
1113			continue;
1114
1115		bar_addrs[bar_cnt++] = bar_addr;
1116	}
1117
1118	return bar_cnt;
1119}
1120
1121static int switchtec_ntb_init_crosslink(struct switchtec_ntb *sndev)
1122{
1123	int rc;
1124	int bar = sndev->direct_mw_to_bar[0];
1125	const int ntb_lut_idx = 1;
1126	u64 bar_addrs[6];
1127	u64 addr;
1128	int offset;
1129	int bar_cnt;
1130
1131	if (!crosslink_is_enabled(sndev))
1132		return 0;
1133
1134	dev_info(&sndev->stdev->dev, "Using crosslink configuration\n");
1135	sndev->ntb.topo = NTB_TOPO_CROSSLINK;
1136
1137	bar_cnt = crosslink_enum_partition(sndev, bar_addrs);
1138	if (bar_cnt < sndev->nr_direct_mw + 1) {
1139		dev_err(&sndev->stdev->dev,
1140			"Error enumerating crosslink partition\n");
1141		return -EINVAL;
1142	}
1143
1144	addr = (bar_addrs[0] + SWITCHTEC_GAS_NTB_OFFSET +
1145		SWITCHTEC_NTB_REG_DBMSG_OFFSET +
1146		sizeof(struct ntb_dbmsg_regs) * sndev->peer_partition);
1147
1148	offset = addr & (LUT_SIZE - 1);
1149	addr -= offset;
1150
1151	rc = config_rsvd_lut_win(sndev, sndev->mmio_self_ctrl, ntb_lut_idx,
1152				 sndev->peer_partition, addr);
1153	if (rc)
1154		return rc;
1155
1156	rc = crosslink_setup_mws(sndev, ntb_lut_idx, &bar_addrs[1],
1157				 bar_cnt - 1);
1158	if (rc)
1159		return rc;
1160
1161	rc = crosslink_setup_req_ids(sndev, sndev->mmio_peer_ctrl);
1162	if (rc)
1163		return rc;
1164
1165	sndev->mmio_xlink_win = pci_iomap_range(sndev->stdev->pdev, bar,
1166						LUT_SIZE, LUT_SIZE);
1167	if (!sndev->mmio_xlink_win) {
1168		rc = -ENOMEM;
1169		return rc;
1170	}
1171
1172	sndev->mmio_peer_dbmsg = sndev->mmio_xlink_win + offset;
1173	sndev->nr_rsvd_luts++;
1174
1175	crosslink_init_dbmsgs(sndev);
1176
1177	return 0;
1178}
1179
1180static void switchtec_ntb_deinit_crosslink(struct switchtec_ntb *sndev)
1181{
1182	if (sndev->mmio_xlink_win)
1183		pci_iounmap(sndev->stdev->pdev, sndev->mmio_xlink_win);
1184}
1185
1186static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
1187{
1188	int i;
1189	int cnt = 0;
1190
1191	for (i = 0; i < ARRAY_SIZE(ctrl->bar_entry); i++) {
1192		u32 r = ioread32(&ctrl->bar_entry[i].ctl);
1193
1194		if (r & NTB_CTRL_BAR_VALID)
1195			map[cnt++] = i;
1196	}
1197
1198	return cnt;
1199}
1200
1201static void switchtec_ntb_init_mw(struct switchtec_ntb *sndev)
1202{
1203	sndev->nr_direct_mw = map_bars(sndev->direct_mw_to_bar,
1204				       sndev->mmio_self_ctrl);
1205
1206	sndev->nr_lut_mw = ioread16(&sndev->mmio_self_ctrl->lut_table_entries);
1207	sndev->nr_lut_mw = rounddown_pow_of_two(sndev->nr_lut_mw);
1208
1209	dev_dbg(&sndev->stdev->dev, "MWs: %d direct, %d lut\n",
1210		sndev->nr_direct_mw, sndev->nr_lut_mw);
1211
1212	sndev->peer_nr_direct_mw = map_bars(sndev->peer_direct_mw_to_bar,
1213					    sndev->mmio_peer_ctrl);
1214
1215	sndev->peer_nr_lut_mw =
1216		ioread16(&sndev->mmio_peer_ctrl->lut_table_entries);
1217	sndev->peer_nr_lut_mw = rounddown_pow_of_two(sndev->peer_nr_lut_mw);
1218
1219	dev_dbg(&sndev->stdev->dev, "Peer MWs: %d direct, %d lut\n",
1220		sndev->peer_nr_direct_mw, sndev->peer_nr_lut_mw);
1221
1222}
1223
1224/*
1225 * There are 64 doorbells in the switch hardware but this is
1226 * shared among all partitions. So we must split them in half
1227 * (32 for each partition). However, the message interrupts are
1228 * also shared with the top 4 doorbells so we just limit this to
1229 * 28 doorbells per partition.
1230 *
1231 * In crosslink mode, each side has it's own dbmsg register so
1232 * they can each use all 60 of the available doorbells.
1233 */
1234static void switchtec_ntb_init_db(struct switchtec_ntb *sndev)
1235{
1236	sndev->db_mask = 0x0FFFFFFFFFFFFFFFULL;
1237
1238	if (sndev->mmio_peer_dbmsg != sndev->mmio_self_dbmsg) {
1239		sndev->db_shift = 0;
1240		sndev->db_peer_shift = 0;
1241		sndev->db_valid_mask = sndev->db_mask;
1242	} else if (sndev->self_partition < sndev->peer_partition) {
1243		sndev->db_shift = 0;
1244		sndev->db_peer_shift = 32;
1245		sndev->db_valid_mask = 0x0FFFFFFF;
1246	} else {
1247		sndev->db_shift = 32;
1248		sndev->db_peer_shift = 0;
1249		sndev->db_valid_mask = 0x0FFFFFFF;
1250	}
1251
1252	iowrite64(~sndev->db_mask, &sndev->mmio_self_dbmsg->idb_mask);
1253	iowrite64(sndev->db_valid_mask << sndev->db_peer_shift,
1254		  &sndev->mmio_peer_dbmsg->odb_mask);
1255
1256	dev_dbg(&sndev->stdev->dev, "dbs: shift %d/%d, mask %016llx\n",
1257		sndev->db_shift, sndev->db_peer_shift, sndev->db_valid_mask);
1258}
1259
1260static void switchtec_ntb_init_msgs(struct switchtec_ntb *sndev)
1261{
1262	int i;
1263	u32 msg_map = 0;
1264
1265	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
1266		int m = i | sndev->peer_partition << 2;
1267
1268		msg_map |= m << i * 8;
1269	}
1270
1271	iowrite32(msg_map, &sndev->mmio_self_dbmsg->msg_map);
1272
1273	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++)
1274		iowrite64(NTB_DBMSG_IMSG_STATUS | NTB_DBMSG_IMSG_MASK,
1275			  &sndev->mmio_self_dbmsg->imsg[i]);
1276}
1277
1278static int
1279switchtec_ntb_init_req_id_table(struct switchtec_ntb *sndev)
1280{
1281	int req_ids[2];
1282
1283	/*
1284	 * Root Complex Requester ID (which is 0:00.0)
1285	 */
1286	req_ids[0] = 0;
1287
1288	/*
1289	 * Host Bridge Requester ID (as read from the mmap address)
1290	 */
1291	req_ids[1] = ioread16(&sndev->mmio_ntb->requester_id);
1292
1293	return config_req_id_table(sndev, sndev->mmio_self_ctrl, req_ids,
1294				   ARRAY_SIZE(req_ids));
1295}
1296
1297static void switchtec_ntb_init_shared(struct switchtec_ntb *sndev)
1298{
1299	int i;
1300
1301	memset(sndev->self_shared, 0, LUT_SIZE);
1302	sndev->self_shared->magic = SWITCHTEC_NTB_MAGIC;
1303	sndev->self_shared->partition_id = sndev->stdev->partition;
1304
1305	for (i = 0; i < sndev->nr_direct_mw; i++) {
1306		int bar = sndev->direct_mw_to_bar[i];
1307		resource_size_t sz = pci_resource_len(sndev->stdev->pdev, bar);
1308
1309		if (i == 0)
1310			sz = min_t(resource_size_t, sz,
1311				   LUT_SIZE * sndev->nr_lut_mw);
1312
1313		sndev->self_shared->mw_sizes[i] = sz;
1314	}
1315
1316	for (i = 0; i < sndev->nr_lut_mw; i++) {
1317		int idx = sndev->nr_direct_mw + i;
1318
1319		sndev->self_shared->mw_sizes[idx] = LUT_SIZE;
1320	}
1321}
1322
1323static int switchtec_ntb_init_shared_mw(struct switchtec_ntb *sndev)
1324{
1325	int self_bar = sndev->direct_mw_to_bar[0];
1326	int rc;
1327
1328	sndev->nr_rsvd_luts++;
1329	sndev->self_shared = dma_alloc_coherent(&sndev->stdev->pdev->dev,
1330						LUT_SIZE,
1331						&sndev->self_shared_dma,
1332						GFP_KERNEL);
1333	if (!sndev->self_shared) {
1334		dev_err(&sndev->stdev->dev,
1335			"unable to allocate memory for shared mw\n");
1336		return -ENOMEM;
1337	}
1338
1339	switchtec_ntb_init_shared(sndev);
1340
1341	rc = config_rsvd_lut_win(sndev, sndev->mmio_peer_ctrl, 0,
1342				 sndev->self_partition,
1343				 sndev->self_shared_dma);
1344	if (rc)
1345		goto unalloc_and_exit;
1346
1347	sndev->peer_shared = pci_iomap(sndev->stdev->pdev, self_bar, LUT_SIZE);
1348	if (!sndev->peer_shared) {
1349		rc = -ENOMEM;
1350		goto unalloc_and_exit;
1351	}
1352
1353	dev_dbg(&sndev->stdev->dev, "Shared MW Ready\n");
1354	return 0;
1355
1356unalloc_and_exit:
1357	dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
1358			  sndev->self_shared, sndev->self_shared_dma);
1359
1360	return rc;
1361}
1362
1363static void switchtec_ntb_deinit_shared_mw(struct switchtec_ntb *sndev)
1364{
1365	if (sndev->peer_shared)
1366		pci_iounmap(sndev->stdev->pdev, sndev->peer_shared);
1367
1368	if (sndev->self_shared)
1369		dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
1370				  sndev->self_shared,
1371				  sndev->self_shared_dma);
1372	sndev->nr_rsvd_luts--;
1373}
1374
1375static irqreturn_t switchtec_ntb_doorbell_isr(int irq, void *dev)
1376{
1377	struct switchtec_ntb *sndev = dev;
1378
1379	dev_dbg(&sndev->stdev->dev, "doorbell\n");
1380
1381	ntb_db_event(&sndev->ntb, 0);
1382
1383	return IRQ_HANDLED;
1384}
1385
1386static irqreturn_t switchtec_ntb_message_isr(int irq, void *dev)
1387{
1388	int i;
1389	struct switchtec_ntb *sndev = dev;
1390
1391	for (i = 0; i < ARRAY_SIZE(sndev->mmio_self_dbmsg->imsg); i++) {
1392		u64 msg = ioread64(&sndev->mmio_self_dbmsg->imsg[i]);
1393
1394		if (msg & NTB_DBMSG_IMSG_STATUS) {
1395			dev_dbg(&sndev->stdev->dev, "message: %d %08x\n",
1396				i, (u32)msg);
1397			iowrite8(1, &sndev->mmio_self_dbmsg->imsg[i].status);
1398
1399			if (i == LINK_MESSAGE)
1400				switchtec_ntb_check_link(sndev, msg);
1401		}
1402	}
1403
1404	return IRQ_HANDLED;
1405}
1406
1407static int switchtec_ntb_init_db_msg_irq(struct switchtec_ntb *sndev)
1408{
1409	int i;
1410	int rc;
1411	int doorbell_irq = 0;
1412	int message_irq = 0;
1413	int event_irq;
1414	int idb_vecs = sizeof(sndev->mmio_self_dbmsg->idb_vec_map);
1415
1416	event_irq = ioread32(&sndev->stdev->mmio_part_cfg->vep_vector_number);
1417
1418	while (doorbell_irq == event_irq)
1419		doorbell_irq++;
1420	while (message_irq == doorbell_irq ||
1421	       message_irq == event_irq)
1422		message_irq++;
1423
1424	dev_dbg(&sndev->stdev->dev, "irqs - event: %d, db: %d, msgs: %d\n",
1425		event_irq, doorbell_irq, message_irq);
1426
1427	for (i = 0; i < idb_vecs - 4; i++)
1428		iowrite8(doorbell_irq,
1429			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
1430
1431	for (; i < idb_vecs; i++)
1432		iowrite8(message_irq,
1433			 &sndev->mmio_self_dbmsg->idb_vec_map[i]);
1434
1435	sndev->doorbell_irq = pci_irq_vector(sndev->stdev->pdev, doorbell_irq);
1436	sndev->message_irq = pci_irq_vector(sndev->stdev->pdev, message_irq);
1437
1438	rc = request_irq(sndev->doorbell_irq,
1439			 switchtec_ntb_doorbell_isr, 0,
1440			 "switchtec_ntb_doorbell", sndev);
1441	if (rc)
1442		return rc;
1443
1444	rc = request_irq(sndev->message_irq,
1445			 switchtec_ntb_message_isr, 0,
1446			 "switchtec_ntb_message", sndev);
1447	if (rc) {
1448		free_irq(sndev->doorbell_irq, sndev);
1449		return rc;
1450	}
1451
1452	return 0;
1453}
1454
1455static void switchtec_ntb_deinit_db_msg_irq(struct switchtec_ntb *sndev)
1456{
1457	free_irq(sndev->doorbell_irq, sndev);
1458	free_irq(sndev->message_irq, sndev);
1459}
1460
1461static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev)
1462{
1463	int rc;
1464
1465	if (crosslink_is_enabled(sndev))
1466		return 0;
1467
1468	dev_info(&sndev->stdev->dev, "reinitialize shared memory window\n");
1469	rc = config_rsvd_lut_win(sndev, sndev->mmio_peer_ctrl, 0,
1470				 sndev->self_partition,
1471				 sndev->self_shared_dma);
1472	return rc;
1473}
1474
1475static int switchtec_ntb_add(struct device *dev,
1476			     struct class_interface *class_intf)
1477{
1478	struct switchtec_dev *stdev = to_stdev(dev);
1479	struct switchtec_ntb *sndev;
1480	int rc;
1481
1482	stdev->sndev = NULL;
1483
1484	if (stdev->pdev->class != (PCI_CLASS_BRIDGE_OTHER << 8))
1485		return -ENODEV;
1486
1487	sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev));
1488	if (!sndev)
1489		return -ENOMEM;
1490
1491	sndev->stdev = stdev;
1492	rc = switchtec_ntb_init_sndev(sndev);
1493	if (rc)
1494		goto free_and_exit;
1495
1496	switchtec_ntb_init_mw(sndev);
1497
1498	rc = switchtec_ntb_init_req_id_table(sndev);
1499	if (rc)
1500		goto free_and_exit;
1501
1502	rc = switchtec_ntb_init_crosslink(sndev);
1503	if (rc)
1504		goto free_and_exit;
1505
1506	switchtec_ntb_init_db(sndev);
1507	switchtec_ntb_init_msgs(sndev);
1508
1509	rc = switchtec_ntb_init_shared_mw(sndev);
1510	if (rc)
1511		goto deinit_crosslink;
1512
1513	rc = switchtec_ntb_init_db_msg_irq(sndev);
1514	if (rc)
1515		goto deinit_shared_and_exit;
1516
1517	/*
1518	 * If this host crashed, the other host may think the link is
1519	 * still up. Tell them to force it down (it will go back up
1520	 * once we register the ntb device).
1521	 */
1522	switchtec_ntb_send_msg(sndev, LINK_MESSAGE, MSG_LINK_FORCE_DOWN);
1523
1524	rc = ntb_register_device(&sndev->ntb);
1525	if (rc)
1526		goto deinit_and_exit;
1527
1528	stdev->sndev = sndev;
1529	stdev->link_notifier = switchtec_ntb_link_notification;
1530	dev_info(dev, "NTB device registered\n");
1531
1532	return 0;
1533
1534deinit_and_exit:
1535	switchtec_ntb_deinit_db_msg_irq(sndev);
1536deinit_shared_and_exit:
1537	switchtec_ntb_deinit_shared_mw(sndev);
1538deinit_crosslink:
1539	switchtec_ntb_deinit_crosslink(sndev);
1540free_and_exit:
1541	kfree(sndev);
1542	dev_err(dev, "failed to register ntb device: %d\n", rc);
1543	return rc;
1544}
1545
1546static void switchtec_ntb_remove(struct device *dev,
1547				 struct class_interface *class_intf)
1548{
1549	struct switchtec_dev *stdev = to_stdev(dev);
1550	struct switchtec_ntb *sndev = stdev->sndev;
1551
1552	if (!sndev)
1553		return;
1554
1555	stdev->link_notifier = NULL;
1556	stdev->sndev = NULL;
1557	ntb_unregister_device(&sndev->ntb);
1558	switchtec_ntb_deinit_db_msg_irq(sndev);
1559	switchtec_ntb_deinit_shared_mw(sndev);
1560	switchtec_ntb_deinit_crosslink(sndev);
1561	kfree(sndev);
1562	dev_info(dev, "ntb device unregistered\n");
1563}
1564
1565static struct class_interface switchtec_interface  = {
1566	.add_dev = switchtec_ntb_add,
1567	.remove_dev = switchtec_ntb_remove,
1568};
1569
1570static int __init switchtec_ntb_init(void)
1571{
1572	switchtec_interface.class = switchtec_class;
1573	return class_interface_register(&switchtec_interface);
1574}
1575module_init(switchtec_ntb_init);
1576
1577static void __exit switchtec_ntb_exit(void)
1578{
1579	class_interface_unregister(&switchtec_interface);
1580}
1581module_exit(switchtec_ntb_exit);
1582