summaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/sgi_hotplug.c
blob: a32ae82e59220b22a8cd305b69eed2971024a55e (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
586
587
588
589
590
591
592
593
594
595
596
597
598
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2005 Silicon Graphics, Inc. All rights reserved.
 *
 * This work was based on the 2.4/2.6 kernel development by Dick Reigner.
 * Work to add BIOS PROM support was completed by Mike Habeck.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <linux/types.h>

#include <asm/sn/addrs.h>
#include <asm/sn/l1.h>
#include <asm/sn/module.h>
#include <asm/sn/pcibr_provider.h>
#include <asm/sn/pcibus_provider_defs.h>
#include <asm/sn/pcidev.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/types.h>

#include "../pci.h"
#include "pci_hotplug.h"

MODULE_LICENSE("GPL");
MODULE_AUTHOR("SGI (prarit@sgi.com, dickie@sgi.com, habeck@sgi.com)");
MODULE_DESCRIPTION("SGI Altix Hot Plug PCI Controller Driver");

#define PCIIO_ASIC_TYPE_TIOCA		4
#define PCI_SLOT_ALREADY_UP		2	/* slot already up */
#define PCI_SLOT_ALREADY_DOWN		3	/* slot already down */
#define PCI_L1_ERR			7	/* L1 console command error */
#define PCI_EMPTY_33MHZ			15	/* empty 33 MHz bus */
#define PCI_L1_QSIZE			128	/* our L1 message buffer size */
#define SN_MAX_HP_SLOTS			32	/* max hotplug slots */
#define SGI_HOTPLUG_PROM_REV		0x0430	/* Min. required PROM version */
#define SN_SLOT_NAME_SIZE		33	/* size of name string */

/* internal list head */
static struct list_head sn_hp_list;

/* hotplug_slot struct's private pointer */
struct slot {
	int device_num;
	struct pci_bus *pci_bus;
	/* this struct for glue internal only */
	struct hotplug_slot *hotplug_slot;
	struct list_head hp_list;
	char physical_path[SN_SLOT_NAME_SIZE];
};

struct pcibr_slot_enable_resp {
	int resp_sub_errno;
	char resp_l1_msg[PCI_L1_QSIZE + 1];
};

struct pcibr_slot_disable_resp {
	int resp_sub_errno;
	char resp_l1_msg[PCI_L1_QSIZE + 1];
};

enum sn_pci_req_e {
	PCI_REQ_SLOT_ELIGIBLE,
	PCI_REQ_SLOT_DISABLE
};

static int enable_slot(struct hotplug_slot *slot);
static int disable_slot(struct hotplug_slot *slot);
static inline int get_power_status(struct hotplug_slot *slot, u8 *value);

static struct hotplug_slot_ops sn_hotplug_slot_ops = {
	.owner                  = THIS_MODULE,
	.enable_slot            = enable_slot,
	.disable_slot           = disable_slot,
	.get_power_status       = get_power_status,
};

static DECLARE_MUTEX(sn_hotplug_sem);

static ssize_t path_show (struct hotplug_slot *bss_hotplug_slot,
	       		  char *buf)
{
	int retval = -ENOENT;
	struct slot *slot = bss_hotplug_slot->private;

	if (!slot)
		return retval;

	retval = sprintf (buf, "%s\n", slot->physical_path);
	return retval;
}

static struct hotplug_slot_attribute sn_slot_path_attr = __ATTR_RO(path);

static int sn_pci_slot_valid(struct pci_bus *pci_bus, int device)
{
	struct pcibus_info *pcibus_info;
	int bricktype;
	int bus_num;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);

	/* Check to see if this is a valid slot on 'pci_bus' */
	if (!(pcibus_info->pbi_valid_devices & (1 << device)))
		return -EPERM;

	bricktype = MODULE_GET_BTYPE(pcibus_info->pbi_moduleid);
	bus_num = pcibus_info->pbi_buscommon.bs_persist_busnum & 0xf;

	/* Do not allow hotplug operations on base I/O cards */
	if ((bricktype == L1_BRICKTYPE_IX ||  bricktype == L1_BRICKTYPE_IA) &&
	    (bus_num == 1 && device != 1))
		return -EPERM;

	return 1;
}

static int sn_pci_bus_valid(struct pci_bus *pci_bus)
{
	struct pcibus_info *pcibus_info;
	int asic_type;
	int bricktype;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);

	/* Don't register slots hanging off the TIOCA bus */
	asic_type = pcibus_info->pbi_buscommon.bs_asic_type;
	if (asic_type == PCIIO_ASIC_TYPE_TIOCA)
		return -EPERM;

	/* Only register slots in I/O Bricks that support hotplug */
	bricktype = MODULE_GET_BTYPE(pcibus_info->pbi_moduleid);
	switch (bricktype) {
		case L1_BRICKTYPE_IX:
		case L1_BRICKTYPE_PX:
		case L1_BRICKTYPE_IA:
		case L1_BRICKTYPE_PA:
			return 1;
			break;
		default:
			return -EPERM;
			break;
	}

	return -EIO;
}

static int sn_hp_slot_private_alloc(struct hotplug_slot *bss_hotplug_slot,
				    struct pci_bus *pci_bus, int device)
{
	struct pcibus_info *pcibus_info;
	struct slot *slot;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);

	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	if (!slot)
		return -ENOMEM;
	bss_hotplug_slot->private = slot;

	bss_hotplug_slot->name = kmalloc(SN_SLOT_NAME_SIZE, GFP_KERNEL);
	if (!bss_hotplug_slot->name) {
		kfree(bss_hotplug_slot->private);
		return -ENOMEM;
	}

	slot->device_num = device;
	slot->pci_bus = pci_bus;
	sprintf(bss_hotplug_slot->name, "%04x:%02x:%02x",
		pci_domain_nr(pci_bus),
		((int)pcibus_info->pbi_buscommon.bs_persist_busnum) & 0xf,
		device + 1);
	sprintf(slot->physical_path, "module_%c%c%c%c%.2d",
		'0'+RACK_GET_CLASS(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
		'0'+RACK_GET_GROUP(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
		'0'+RACK_GET_NUM(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
		MODULE_GET_BTCHAR(pcibus_info->pbi_moduleid),
		MODULE_GET_BPOS(pcibus_info->pbi_moduleid));
	slot->hotplug_slot = bss_hotplug_slot;
	list_add(&slot->hp_list, &sn_hp_list);

	return 0;
}

static struct hotplug_slot * sn_hp_destroy(void)
{
	struct slot *slot;
	struct hotplug_slot *bss_hotplug_slot = NULL;

	list_for_each_entry(slot, &sn_hp_list, hp_list) {
		bss_hotplug_slot = slot->hotplug_slot;
		list_del(&((struct slot *)bss_hotplug_slot->private)->
			 hp_list);
		sysfs_remove_file(&bss_hotplug_slot->kobj,
				  &sn_slot_path_attr.attr);
		break;
	}
	return bss_hotplug_slot;
}

static void sn_bus_alloc_data(struct pci_dev *dev)
{
	struct pci_bus *subordinate_bus;
	struct pci_dev *child;

	sn_pci_fixup_slot(dev);

	/* Recursively sets up the sn_irq_info structs */
	if (dev->subordinate) {
		subordinate_bus = dev->subordinate;
		list_for_each_entry(child, &subordinate_bus->devices, bus_list)
			sn_bus_alloc_data(child);
	}
}

static void sn_bus_free_data(struct pci_dev *dev)
{
	struct pci_bus *subordinate_bus;
	struct pci_dev *child;

	/* Recursively clean up sn_irq_info structs */
	if (dev->subordinate) {
		subordinate_bus = dev->subordinate;
		list_for_each_entry(child, &subordinate_bus->devices, bus_list)
			sn_bus_free_data(child);
	}
	sn_pci_unfixup_slot(dev);
}

static int sn_slot_enable(struct hotplug_slot *bss_hotplug_slot,
			  int device_num)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pcibus_info *pcibus_info;
	struct pcibr_slot_enable_resp resp;
	int rc;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);

	/*
	 * Power-on and initialize the slot in the SN
	 * PCI infrastructure.
	 */
	rc = sal_pcibr_slot_enable(pcibus_info, device_num, &resp);

	if (rc == PCI_SLOT_ALREADY_UP) {
		dev_dbg(slot->pci_bus->self, "is already active\n");
		return 1; /* return 1 to user */
	}

	if (rc == PCI_L1_ERR) {
		dev_dbg(slot->pci_bus->self,
			"L1 failure %d with message: %s",
			resp.resp_sub_errno, resp.resp_l1_msg);
		return -EPERM;
	}

	if (rc) {
		dev_dbg(slot->pci_bus->self,
			"insert failed with error %d sub-error %d\n",
			rc, resp.resp_sub_errno);
		return -EIO;
	}

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
	pcibus_info->pbi_enabled_devices |= (1 << device_num);

	return 0;
}

static int sn_slot_disable(struct hotplug_slot *bss_hotplug_slot,
			   int device_num, int action)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pcibus_info *pcibus_info;
	struct pcibr_slot_disable_resp resp;
	int rc;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);

	rc = sal_pcibr_slot_disable(pcibus_info, device_num, action, &resp);

	if ((action == PCI_REQ_SLOT_ELIGIBLE) &&
	    (rc == PCI_SLOT_ALREADY_DOWN)) {
		dev_dbg(slot->pci_bus->self, "Slot %s already inactive\n");
		return 1; /* return 1 to user */
	}

	if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_EMPTY_33MHZ)) {
		dev_dbg(slot->pci_bus->self,
			"Cannot remove last 33MHz card\n");
		return -EPERM;
	}

	if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_L1_ERR)) {
		dev_dbg(slot->pci_bus->self,
			"L1 failure %d with message \n%s\n",
			resp.resp_sub_errno, resp.resp_l1_msg);
		return -EPERM;
	}

	if ((action == PCI_REQ_SLOT_ELIGIBLE) && rc) {
		dev_dbg(slot->pci_bus->self,
			"remove failed with error %d sub-error %d\n",
			rc, resp.resp_sub_errno);
		return -EIO;
	}

	if ((action == PCI_REQ_SLOT_ELIGIBLE) && !rc)
		return 0;

	if ((action == PCI_REQ_SLOT_DISABLE) && !rc) {
		pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
		pcibus_info->pbi_enabled_devices &= ~(1 << device_num);
		dev_dbg(slot->pci_bus->self, "remove successful\n");
		return 0;
	}

	if ((action == PCI_REQ_SLOT_DISABLE) && rc) {
		dev_dbg(slot->pci_bus->self,"remove failed rc = %d\n", rc);
	}

	return rc;
}

static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pci_bus *new_bus = NULL;
	struct pci_dev *dev;
	int func, num_funcs;
	int new_ppb = 0;
	int rc;

	/* Serialize the Linux PCI infrastructure */
	down(&sn_hotplug_sem);

	/*
	 * Power-on and initialize the slot in the SN
	 * PCI infrastructure.
	 */
	rc = sn_slot_enable(bss_hotplug_slot, slot->device_num);
	if (rc) {
		up(&sn_hotplug_sem);
		return rc;
	}

	num_funcs = pci_scan_slot(slot->pci_bus,
				  PCI_DEVFN(slot->device_num + 1, 0));
	if (!num_funcs) {
		dev_dbg(slot->pci_bus->self, "no device in slot\n");
		up(&sn_hotplug_sem);
		return -ENODEV;
	}

	sn_pci_controller_fixup(pci_domain_nr(slot->pci_bus),
				slot->pci_bus->number,
				slot->pci_bus);
	/*
	 * Map SN resources for all functions on the card
	 * to the Linux PCI interface and tell the drivers
	 * about them.
	 */
	for (func = 0; func < num_funcs;  func++) {
		dev = pci_get_slot(slot->pci_bus,
				   PCI_DEVFN(slot->device_num + 1,
					     PCI_FUNC(func)));
		if (dev) {
			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
				unsigned char sec_bus;
				pci_read_config_byte(dev, PCI_SECONDARY_BUS,
						     &sec_bus);
				new_bus = pci_add_new_bus(dev->bus, dev,
							  sec_bus);
				pci_scan_child_bus(new_bus);
				sn_pci_controller_fixup(pci_domain_nr(new_bus),
							new_bus->number,
							new_bus);
				new_ppb = 1;
			}
			sn_bus_alloc_data(dev);
			pci_dev_put(dev);
		}
	}

	/* Call the driver for the new device */
	pci_bus_add_devices(slot->pci_bus);
	/* Call the drivers for the new devices subordinate to PPB */
	if (new_ppb)
		pci_bus_add_devices(new_bus);

	up(&sn_hotplug_sem);

	if (rc == 0)
		dev_dbg(slot->pci_bus->self,
			"insert operation successful\n");
	else
		dev_dbg(slot->pci_bus->self,
			"insert operation failed rc = %d\n", rc);

	return rc;
}

static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pci_dev *dev;
	int func;
	int rc;

	/* Acquire update access to the bus */
	down(&sn_hotplug_sem);

	/* is it okay to bring this slot down? */
	rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
			     PCI_REQ_SLOT_ELIGIBLE);
	if (rc)
		goto leaving;

	/* Free the SN resources assigned to the Linux device.*/
	for (func = 0; func < 8;  func++) {
		dev = pci_get_slot(slot->pci_bus,
				   PCI_DEVFN(slot->device_num + 1,
				   	     PCI_FUNC(func)));
		if (dev) {
			/*
			 * Some drivers may use dma accesses during the
			 * driver remove function. We release the sysdata
			 * areas after the driver remove functions have
			 * been called.
			 */
			sn_bus_store_sysdata(dev);
			sn_bus_free_data(dev);
			pci_remove_bus_device(dev);
			pci_dev_put(dev);
		}
	}

	/* free the collected sysdata pointers */
	sn_bus_free_sysdata();

	/* Deactivate slot */
	rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
			     PCI_REQ_SLOT_DISABLE);
 leaving:
	/* Release the bus lock */
	up(&sn_hotplug_sem);

	return rc;
}

static inline int get_power_status(struct hotplug_slot *bss_hotplug_slot,
				   u8 *value)
{
	struct slot *slot = bss_hotplug_slot->private;
	struct pcibus_info *pcibus_info;

	pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
	down(&sn_hotplug_sem);
	*value = pcibus_info->pbi_enabled_devices & (1 << slot->device_num);
	up(&sn_hotplug_sem);
	return 0;
}

static void sn_release_slot(struct hotplug_slot *bss_hotplug_slot)
{
	kfree(bss_hotplug_slot->info);
	kfree(bss_hotplug_slot->name);
	kfree(bss_hotplug_slot->private);
	kfree(bss_hotplug_slot);
}

static int sn_hotplug_slot_register(struct pci_bus *pci_bus)
{
	int device;
	struct hotplug_slot *bss_hotplug_slot;
	int rc = 0;

	/*
	 * Currently only four devices are supported,
	 * in the future there maybe more -- up to 32.
	 */

	for (device = 0; device < SN_MAX_HP_SLOTS ; device++) {
		if (sn_pci_slot_valid(pci_bus, device) != 1)
			continue;

		bss_hotplug_slot = kzalloc(sizeof(*bss_hotplug_slot),
					   GFP_KERNEL);
		if (!bss_hotplug_slot) {
			rc = -ENOMEM;
			goto alloc_err;
		}

		bss_hotplug_slot->info =
			kzalloc(sizeof(struct hotplug_slot_info),
				GFP_KERNEL);
		if (!bss_hotplug_slot->info) {
			rc = -ENOMEM;
			goto alloc_err;
		}

		if (sn_hp_slot_private_alloc(bss_hotplug_slot,
					     pci_bus, device)) {
			rc = -ENOMEM;
			goto alloc_err;
		}

		bss_hotplug_slot->ops = &sn_hotplug_slot_ops;
		bss_hotplug_slot->release = &sn_release_slot;

		rc = pci_hp_register(bss_hotplug_slot);
		if (rc)
			goto register_err;

		rc = sysfs_create_file(&bss_hotplug_slot->kobj,
				       &sn_slot_path_attr.attr);
		if (rc)
			goto register_err;
	}
	dev_dbg(pci_bus->self, "Registered bus with hotplug\n");
	return rc;

register_err:
	dev_dbg(pci_bus->self, "bus failed to register with err = %d\n",
	        rc);

alloc_err:
	if (rc == -ENOMEM)
		dev_dbg(pci_bus->self, "Memory allocation error\n");

	/* destroy THIS element */
	if (bss_hotplug_slot)
		sn_release_slot(bss_hotplug_slot);

	/* destroy anything else on the list */
	while ((bss_hotplug_slot = sn_hp_destroy()))
		pci_hp_deregister(bss_hotplug_slot);

	return rc;
}

static int sn_pci_hotplug_init(void)
{
	struct pci_bus *pci_bus = NULL;
	int rc;
	int registered = 0;

	if (sn_sal_rev() < SGI_HOTPLUG_PROM_REV) {
		printk(KERN_ERR "%s: PROM version must be greater than 4.30\n",
		       __FUNCTION__);
		return -EPERM;
	}

	INIT_LIST_HEAD(&sn_hp_list);

	while ((pci_bus = pci_find_next_bus(pci_bus))) {
		if (!pci_bus->sysdata)
			continue;

		rc = sn_pci_bus_valid(pci_bus);
		if (rc != 1) {
			dev_dbg(pci_bus->self, "not a valid hotplug bus\n");
			continue;
		}
		dev_dbg(pci_bus->self, "valid hotplug bus\n");

		rc = sn_hotplug_slot_register(pci_bus);
		if (!rc) {
			registered = 1;
		} else {
			registered = 0;
			break;
		}
	}

	return registered == 1 ? 0 : -ENODEV;
}

static void sn_pci_hotplug_exit(void)
{
	struct hotplug_slot *bss_hotplug_slot;

	while ((bss_hotplug_slot = sn_hp_destroy()))
		pci_hp_deregister(bss_hotplug_slot);

	if (!list_empty(&sn_hp_list))
		printk(KERN_ERR "%s: internal list is not empty\n", __FILE__);
}

module_init(sn_pci_hotplug_init);
module_exit(sn_pci_hotplug_exit);
OpenPOWER on IntegriCloud