summaryrefslogtreecommitdiff
path: root/arch/s390/pci/pci.c
blob: 70f6c56c8d0f30b8b635980b6624d42a06b65233 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
/*
 * Copyright IBM Corp. 2012
 *
 * Author(s):
 *   Jan Glauber <jang@linux.vnet.ibm.com>
 *
 * The System z PCI code is a rewrite from a prototype by
 * the following people (Kudoz!):
 *   Alexander Schmidt <alexschm@de.ibm.com>
 *   Christoph Raisch <raisch@de.ibm.com>
 *   Hannes Hering <hering2@de.ibm.com>
 *   Hoang-Nam Nguyen <hnguyen@de.ibm.com>
 *   Jan-Bernd Themann <themann@de.ibm.com>
 *   Stefan Roscher <stefan.roscher@de.ibm.com>
 *   Thomas Klein <tklein@de.ibm.com>
 */

#define COMPONENT "zPCI"
#define pr_fmt(fmt) COMPONENT ": " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/pci.h>
#include <linux/msi.h>

#include <asm/facility.h>
#include <asm/pci_insn.h>
#include <asm/pci_clp.h>

#define DEBUG				/* enable pr_debug */

#define ZPCI_NR_DMA_SPACES		1
#define ZPCI_NR_DEVICES			CONFIG_PCI_NR_FUNCTIONS

/* list of all detected zpci devices */
LIST_HEAD(zpci_list);
DEFINE_MUTEX(zpci_list_lock);

static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);
static DEFINE_SPINLOCK(zpci_domain_lock);

/* I/O Map */
static DEFINE_SPINLOCK(zpci_iomap_lock);
static DECLARE_BITMAP(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
struct zpci_iomap_entry *zpci_iomap_start;
EXPORT_SYMBOL_GPL(zpci_iomap_start);

struct zpci_dev *get_zdev(struct pci_dev *pdev)
{
	return (struct zpci_dev *) pdev->sysdata;
}

struct zpci_dev *get_zdev_by_fid(u32 fid)
{
	struct zpci_dev *tmp, *zdev = NULL;

	mutex_lock(&zpci_list_lock);
	list_for_each_entry(tmp, &zpci_list, entry) {
		if (tmp->fid == fid) {
			zdev = tmp;
			break;
		}
	}
	mutex_unlock(&zpci_list_lock);
	return zdev;
}

bool zpci_fid_present(u32 fid)
{
	return (get_zdev_by_fid(fid) != NULL) ? true : false;
}

static struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus)
{
	return (bus && bus->sysdata) ? (struct zpci_dev *) bus->sysdata : NULL;
}

int pci_domain_nr(struct pci_bus *bus)
{
	return ((struct zpci_dev *) bus->sysdata)->domain;
}
EXPORT_SYMBOL_GPL(pci_domain_nr);

int pci_proc_domain(struct pci_bus *bus)
{
	return pci_domain_nr(bus);
}
EXPORT_SYMBOL_GPL(pci_proc_domain);

/* Store PCI function information block */
static int zpci_store_fib(struct zpci_dev *zdev, u8 *fc)
{
	struct zpci_fib *fib;
	u8 status, cc;

	fib = (void *) get_zeroed_page(GFP_KERNEL);
	if (!fib)
		return -ENOMEM;

	do {
		cc = __stpcifc(zdev->fh, 0, fib, &status);
		if (cc == 2) {
			msleep(ZPCI_INSN_BUSY_DELAY);
			memset(fib, 0, PAGE_SIZE);
		}
	} while (cc == 2);

	if (cc)
		pr_err_once("%s: cc: %u  status: %u\n",
			    __func__, cc, status);

	/* Return PCI function controls */
	*fc = fib->fc;

	free_page((unsigned long) fib);
	return (cc) ? -EIO : 0;
}

#define ZPCI_PCIAS_CFGSPC	15

static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
{
	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
	u64 data;
	int rc;

	rc = pcilg_instr(&data, req, offset);
	data = data << ((8 - len) * 8);
	data = le64_to_cpu(data);
	if (!rc)
		*val = (u32) data;
	else
		*val = 0xffffffff;
	return rc;
}

static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
{
	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
	u64 data = val;
	int rc;

	data = cpu_to_le64(data);
	data = data >> ((8 - len) * 8);
	rc = pcistg_instr(data, req, offset);
	return rc;
}

void __devinit pcibios_fixup_bus(struct pci_bus *bus)
{
}

resource_size_t pcibios_align_resource(void *data, const struct resource *res,
				       resource_size_t size,
				       resource_size_t align)
{
	return 0;
}

/* Create a virtual mapping cookie for a PCI BAR */
void __iomem *pci_iomap(struct pci_dev *pdev, int bar, unsigned long max)
{
	struct zpci_dev *zdev =	get_zdev(pdev);
	u64 addr;
	int idx;

	if ((bar & 7) != bar)
		return NULL;

	idx = zdev->bars[bar].map_idx;
	spin_lock(&zpci_iomap_lock);
	zpci_iomap_start[idx].fh = zdev->fh;
	zpci_iomap_start[idx].bar = bar;
	spin_unlock(&zpci_iomap_lock);

	addr = ZPCI_IOMAP_ADDR_BASE | ((u64) idx << 48);
	return (void __iomem *) addr;
}
EXPORT_SYMBOL_GPL(pci_iomap);

void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
{
	unsigned int idx;

	idx = (((__force u64) addr) & ~ZPCI_IOMAP_ADDR_BASE) >> 48;
	spin_lock(&zpci_iomap_lock);
	zpci_iomap_start[idx].fh = 0;
	zpci_iomap_start[idx].bar = 0;
	spin_unlock(&zpci_iomap_lock);
}
EXPORT_SYMBOL_GPL(pci_iounmap);

static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
		    int size, u32 *val)
{
	struct zpci_dev *zdev = get_zdev_by_bus(bus);

	if (!zdev || devfn != ZPCI_DEVFN)
		return 0;
	return zpci_cfg_load(zdev, where, val, size);
}

static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
		     int size, u32 val)
{
	struct zpci_dev *zdev = get_zdev_by_bus(bus);

	if (!zdev || devfn != ZPCI_DEVFN)
		return 0;
	return zpci_cfg_store(zdev, where, val, size);
}

static struct pci_ops pci_root_ops = {
	.read = pci_read,
	.write = pci_write,
};

static void zpci_map_resources(struct zpci_dev *zdev)
{
	struct pci_dev *pdev = zdev->pdev;
	resource_size_t len;
	int i;

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		len = pci_resource_len(pdev, i);
		if (!len)
			continue;
		pdev->resource[i].start = (resource_size_t) pci_iomap(pdev, i, 0);
		pdev->resource[i].end = pdev->resource[i].start + len - 1;
		pr_debug("BAR%i: -> start: %Lx  end: %Lx\n",
			i, pdev->resource[i].start, pdev->resource[i].end);
	}
};

static void zpci_unmap_resources(struct pci_dev *pdev)
{
	resource_size_t len;
	int i;

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		len = pci_resource_len(pdev, i);
		if (!len)
			continue;
		pci_iounmap(pdev, (void *) pdev->resource[i].start);
	}
};

struct zpci_dev *zpci_alloc_device(void)
{
	struct zpci_dev *zdev;

	/* Alloc memory for our private pci device data */
	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
	if (!zdev)
		return ERR_PTR(-ENOMEM);
	return zdev;
}

void zpci_free_device(struct zpci_dev *zdev)
{
	kfree(zdev);
}

/* Called on removal of pci_dev, leaves zpci and bus device */
static void zpci_remove_device(struct pci_dev *pdev)
{
	struct zpci_dev *zdev = get_zdev(pdev);

	dev_info(&pdev->dev, "Removing device %u\n", zdev->domain);
	zdev->state = ZPCI_FN_STATE_CONFIGURED;
	zpci_unmap_resources(pdev);
	list_del(&zdev->entry);		/* can be called from init */
	zdev->pdev = NULL;
}

static void zpci_scan_devices(void)
{
	struct zpci_dev *zdev;

	mutex_lock(&zpci_list_lock);
	list_for_each_entry(zdev, &zpci_list, entry)
		if (zdev->state == ZPCI_FN_STATE_CONFIGURED)
			zpci_scan_device(zdev);
	mutex_unlock(&zpci_list_lock);
}

/*
 * Too late for any s390 specific setup, since interrupts must be set up
 * already which requires DMA setup too and the pci scan will access the
 * config space, which only works if the function handle is enabled.
 */
int pcibios_enable_device(struct pci_dev *pdev, int mask)
{
	struct resource *res;
	u16 cmd;
	int i;

	pci_read_config_word(pdev, PCI_COMMAND, &cmd);

	for (i = 0; i < PCI_BAR_COUNT; i++) {
		res = &pdev->resource[i];

		if (res->flags & IORESOURCE_IO)
			return -EINVAL;

		if (res->flags & IORESOURCE_MEM)
			cmd |= PCI_COMMAND_MEMORY;
	}
	pci_write_config_word(pdev, PCI_COMMAND, cmd);
	return 0;
}

void pcibios_disable_device(struct pci_dev *pdev)
{
	zpci_remove_device(pdev);
	pdev->sysdata = NULL;
}

static struct resource *zpci_alloc_bus_resource(unsigned long start, unsigned long size,
						unsigned long flags, int domain)
{
	struct resource *r;
	char *name;
	int rc;

	r = kzalloc(sizeof(*r), GFP_KERNEL);
	if (!r)
		return ERR_PTR(-ENOMEM);
	r->start = start;
	r->end = r->start + size - 1;
	r->flags = flags;
	r->parent = &iomem_resource;
	name = kmalloc(18, GFP_KERNEL);
	if (!name) {
		kfree(r);
		return ERR_PTR(-ENOMEM);
	}
	sprintf(name, "PCI Bus: %04x:%02x", domain, ZPCI_BUS_NR);
	r->name = name;

	rc = request_resource(&iomem_resource, r);
	if (rc)
		pr_debug("request resource %pR failed\n", r);
	return r;
}

static int zpci_alloc_iomap(struct zpci_dev *zdev)
{
	int entry;

	spin_lock(&zpci_iomap_lock);
	entry = find_first_zero_bit(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
	if (entry == ZPCI_IOMAP_MAX_ENTRIES) {
		spin_unlock(&zpci_iomap_lock);
		return -ENOSPC;
	}
	set_bit(entry, zpci_iomap);
	spin_unlock(&zpci_iomap_lock);
	return entry;
}

static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
{
	spin_lock(&zpci_iomap_lock);
	memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
	clear_bit(entry, zpci_iomap);
	spin_unlock(&zpci_iomap_lock);
}

static int zpci_create_device_bus(struct zpci_dev *zdev)
{
	struct resource *res;
	LIST_HEAD(resources);
	int i;

	/* allocate mapping entry for each used bar */
	for (i = 0; i < PCI_BAR_COUNT; i++) {
		unsigned long addr, size, flags;
		int entry;

		if (!zdev->bars[i].size)
			continue;
		entry = zpci_alloc_iomap(zdev);
		if (entry < 0)
			return entry;
		zdev->bars[i].map_idx = entry;

		/* only MMIO is supported */
		flags = IORESOURCE_MEM;
		if (zdev->bars[i].val & 8)
			flags |= IORESOURCE_PREFETCH;
		if (zdev->bars[i].val & 4)
			flags |= IORESOURCE_MEM_64;

		addr = ZPCI_IOMAP_ADDR_BASE + ((u64) entry << 48);

		size = 1UL << zdev->bars[i].size;

		res = zpci_alloc_bus_resource(addr, size, flags, zdev->domain);
		if (IS_ERR(res)) {
			zpci_free_iomap(zdev, entry);
			return PTR_ERR(res);
		}
		pci_add_resource(&resources, res);
	}

	zdev->bus = pci_create_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops,
					zdev, &resources);
	if (!zdev->bus)
		return -EIO;

	zdev->bus->max_bus_speed = zdev->max_bus_speed;
	return 0;
}

static int zpci_alloc_domain(struct zpci_dev *zdev)
{
	spin_lock(&zpci_domain_lock);
	zdev->domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
	if (zdev->domain == ZPCI_NR_DEVICES) {
		spin_unlock(&zpci_domain_lock);
		return -ENOSPC;
	}
	set_bit(zdev->domain, zpci_domain);
	spin_unlock(&zpci_domain_lock);
	return 0;
}

static void zpci_free_domain(struct zpci_dev *zdev)
{
	spin_lock(&zpci_domain_lock);
	clear_bit(zdev->domain, zpci_domain);
	spin_unlock(&zpci_domain_lock);
}

int zpci_enable_device(struct zpci_dev *zdev)
{
	int rc;

	rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
	if (rc)
		goto out;
	pr_info("Enabled fh: 0x%x fid: 0x%x\n", zdev->fh, zdev->fid);
	return 0;
out:
	return rc;
}
EXPORT_SYMBOL_GPL(zpci_enable_device);

int zpci_create_device(struct zpci_dev *zdev)
{
	int rc;

	rc = zpci_alloc_domain(zdev);
	if (rc)
		goto out;

	rc = zpci_create_device_bus(zdev);
	if (rc)
		goto out_bus;

	mutex_lock(&zpci_list_lock);
	list_add_tail(&zdev->entry, &zpci_list);
	mutex_unlock(&zpci_list_lock);

	if (zdev->state == ZPCI_FN_STATE_STANDBY)
		return 0;

	rc = zpci_enable_device(zdev);
	if (rc)
		goto out_start;
	return 0;

out_start:
	mutex_lock(&zpci_list_lock);
	list_del(&zdev->entry);
	mutex_unlock(&zpci_list_lock);
out_bus:
	zpci_free_domain(zdev);
out:
	return rc;
}

void zpci_stop_device(struct zpci_dev *zdev)
{
	/*
	 * Note: SCLP disables fh via set-pci-fn so don't
	 * do that here.
	 */
}
EXPORT_SYMBOL_GPL(zpci_stop_device);

int zpci_scan_device(struct zpci_dev *zdev)
{
	zdev->pdev = pci_scan_single_device(zdev->bus, ZPCI_DEVFN);
	if (!zdev->pdev) {
		pr_err("pci_scan_single_device failed for fid: 0x%x\n",
			zdev->fid);
		goto out;
	}

	zpci_map_resources(zdev);
	pci_bus_add_devices(zdev->bus);

	/* now that pdev was added to the bus mark it as used */
	zdev->state = ZPCI_FN_STATE_ONLINE;
	return 0;

out:
	clp_disable_fh(zdev);
	return -EIO;
}
EXPORT_SYMBOL_GPL(zpci_scan_device);

static inline int barsize(u8 size)
{
	return (size) ? (1 << size) >> 10 : 0;
}

static int zpci_mem_init(void)
{
	/* TODO: use realloc */
	zpci_iomap_start = kzalloc(ZPCI_IOMAP_MAX_ENTRIES * sizeof(*zpci_iomap_start),
				   GFP_KERNEL);
	if (!zpci_iomap_start)
		goto error_zdev;
	return 0;

error_zdev:
	return -ENOMEM;
}

static void zpci_mem_exit(void)
{
	kfree(zpci_iomap_start);
}

unsigned int pci_probe = 1;
EXPORT_SYMBOL_GPL(pci_probe);

char * __init pcibios_setup(char *str)
{
	if (!strcmp(str, "off")) {
		pci_probe = 0;
		return NULL;
	}
	return str;
}

static int __init pci_base_init(void)
{
	int rc;

	if (!pci_probe)
		return 0;

	if (!test_facility(2) || !test_facility(69)
	    || !test_facility(71) || !test_facility(72))
		return 0;

	pr_info("Probing PCI hardware: PCI:%d  SID:%d  AEN:%d\n",
		test_facility(69), test_facility(70),
		test_facility(71));

	rc = zpci_mem_init();
	if (rc)
		goto out_mem;

	rc = clp_find_pci_devices();
	if (rc)
		goto out_find;

	zpci_scan_devices();
	return 0;

out_find:
	zpci_mem_exit();
out_mem:
	return rc;
}
subsys_initcall(pci_base_init);