xref: /openbmc/linux/drivers/scsi/libsas/sas_init.c (revision 863e99a8c1ea2b0391491904297f57a0f6a1fdd6)
1 /*
2  * Serial Attached SCSI (SAS) Transport Layer initialization
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
22  * USA
23  *
24  */
25 
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/device.h>
30 #include <linux/spinlock.h>
31 #include <scsi/sas_ata.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_device.h>
34 #include <scsi/scsi_transport.h>
35 #include <scsi/scsi_transport_sas.h>
36 
37 #include "sas_internal.h"
38 
39 #include "../scsi_sas_internal.h"
40 
41 static struct kmem_cache *sas_task_cache;
42 
43 struct sas_task *sas_alloc_task(gfp_t flags)
44 {
45 	struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
46 
47 	if (task) {
48 		INIT_LIST_HEAD(&task->list);
49 		spin_lock_init(&task->task_state_lock);
50 		task->task_state_flags = SAS_TASK_STATE_PENDING;
51 	}
52 
53 	return task;
54 }
55 EXPORT_SYMBOL_GPL(sas_alloc_task);
56 
57 struct sas_task *sas_alloc_slow_task(gfp_t flags)
58 {
59 	struct sas_task *task = sas_alloc_task(flags);
60 	struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
61 
62 	if (!task || !slow) {
63 		if (task)
64 			kmem_cache_free(sas_task_cache, task);
65 		kfree(slow);
66 		return NULL;
67 	}
68 
69 	task->slow_task = slow;
70 	init_timer(&slow->timer);
71 	init_completion(&slow->completion);
72 
73 	return task;
74 }
75 EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
76 
77 void sas_free_task(struct sas_task *task)
78 {
79 	if (task) {
80 		BUG_ON(!list_empty(&task->list));
81 		kfree(task->slow_task);
82 		kmem_cache_free(sas_task_cache, task);
83 	}
84 }
85 EXPORT_SYMBOL_GPL(sas_free_task);
86 
87 /*------------ SAS addr hash -----------*/
88 void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
89 {
90         const u32 poly = 0x00DB2777;
91         u32     r = 0;
92         int     i;
93 
94         for (i = 0; i < 8; i++) {
95                 int b;
96                 for (b = 7; b >= 0; b--) {
97                         r <<= 1;
98                         if ((1 << b) & sas_addr[i]) {
99                                 if (!(r & 0x01000000))
100                                         r ^= poly;
101                         } else if (r & 0x01000000)
102                                 r ^= poly;
103                 }
104         }
105 
106         hashed[0] = (r >> 16) & 0xFF;
107         hashed[1] = (r >> 8) & 0xFF ;
108         hashed[2] = r & 0xFF;
109 }
110 
111 
112 /* ---------- HA events ---------- */
113 
114 void sas_hae_reset(struct work_struct *work)
115 {
116 	struct sas_ha_event *ev = to_sas_ha_event(work);
117 	struct sas_ha_struct *ha = ev->ha;
118 
119 	clear_bit(HAE_RESET, &ha->pending);
120 }
121 
122 int sas_register_ha(struct sas_ha_struct *sas_ha)
123 {
124 	int error = 0;
125 
126 	mutex_init(&sas_ha->disco_mutex);
127 	spin_lock_init(&sas_ha->phy_port_lock);
128 	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
129 
130 	if (sas_ha->lldd_queue_size == 0)
131 		sas_ha->lldd_queue_size = 1;
132 	else if (sas_ha->lldd_queue_size == -1)
133 		sas_ha->lldd_queue_size = 128; /* Sanity */
134 
135 	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
136 	spin_lock_init(&sas_ha->lock);
137 	mutex_init(&sas_ha->drain_mutex);
138 	init_waitqueue_head(&sas_ha->eh_wait_q);
139 	INIT_LIST_HEAD(&sas_ha->defer_q);
140 	INIT_LIST_HEAD(&sas_ha->eh_dev_q);
141 
142 	error = sas_register_phys(sas_ha);
143 	if (error) {
144 		printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
145 		return error;
146 	}
147 
148 	error = sas_register_ports(sas_ha);
149 	if (error) {
150 		printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
151 		goto Undo_phys;
152 	}
153 
154 	error = sas_init_events(sas_ha);
155 	if (error) {
156 		printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
157 		goto Undo_ports;
158 	}
159 
160 	if (sas_ha->lldd_max_execute_num > 1) {
161 		error = sas_init_queue(sas_ha);
162 		if (error) {
163 			printk(KERN_NOTICE "couldn't start queue thread:%d, "
164 			       "running in direct mode\n", error);
165 			sas_ha->lldd_max_execute_num = 1;
166 		}
167 	}
168 
169 	INIT_LIST_HEAD(&sas_ha->eh_done_q);
170 	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
171 
172 	return 0;
173 
174 Undo_ports:
175 	sas_unregister_ports(sas_ha);
176 Undo_phys:
177 
178 	return error;
179 }
180 
181 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
182 {
183 	/* Set the state to unregistered to avoid further unchained
184 	 * events to be queued, and flush any in-progress drainers
185 	 */
186 	mutex_lock(&sas_ha->drain_mutex);
187 	spin_lock_irq(&sas_ha->lock);
188 	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
189 	spin_unlock_irq(&sas_ha->lock);
190 	__sas_drain_work(sas_ha);
191 	mutex_unlock(&sas_ha->drain_mutex);
192 
193 	sas_unregister_ports(sas_ha);
194 
195 	/* flush unregistration work */
196 	mutex_lock(&sas_ha->drain_mutex);
197 	__sas_drain_work(sas_ha);
198 	mutex_unlock(&sas_ha->drain_mutex);
199 
200 	if (sas_ha->lldd_max_execute_num > 1) {
201 		sas_shutdown_queue(sas_ha);
202 		sas_ha->lldd_max_execute_num = 1;
203 	}
204 
205 	return 0;
206 }
207 
208 static int sas_get_linkerrors(struct sas_phy *phy)
209 {
210 	if (scsi_is_sas_phy_local(phy)) {
211 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
212 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
213 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
214 		struct sas_internal *i =
215 			to_sas_internal(sas_ha->core.shost->transportt);
216 
217 		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
218 	}
219 
220 	return sas_smp_get_phy_events(phy);
221 }
222 
223 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
224 {
225 	struct domain_device *dev = NULL;
226 
227 	/* try to route user requested link resets through libata */
228 	if (asd_phy->port)
229 		dev = asd_phy->port->port_dev;
230 
231 	/* validate that dev has been probed */
232 	if (dev)
233 		dev = sas_find_dev_by_rphy(dev->rphy);
234 
235 	if (dev && dev_is_sata(dev)) {
236 		sas_ata_schedule_reset(dev);
237 		sas_ata_wait_eh(dev);
238 		return 0;
239 	}
240 
241 	return -ENODEV;
242 }
243 
244 /**
245  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
246  *
247  * phy reset request via sysfs in host workqueue context so we know we
248  * can block on eh and safely traverse the domain_device topology
249  */
250 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
251 {
252 	enum phy_func reset_type;
253 
254 	if (hard_reset)
255 		reset_type = PHY_FUNC_HARD_RESET;
256 	else
257 		reset_type = PHY_FUNC_LINK_RESET;
258 
259 	if (scsi_is_sas_phy_local(phy)) {
260 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
261 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
262 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
263 		struct sas_internal *i =
264 			to_sas_internal(sas_ha->core.shost->transportt);
265 
266 		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
267 			return 0;
268 		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
269 	} else {
270 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
271 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
272 		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
273 
274 		if (ata_dev && !hard_reset) {
275 			sas_ata_schedule_reset(ata_dev);
276 			sas_ata_wait_eh(ata_dev);
277 			return 0;
278 		} else
279 			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
280 	}
281 }
282 
283 static int sas_phy_enable(struct sas_phy *phy, int enable)
284 {
285 	int ret;
286 	enum phy_func cmd;
287 
288 	if (enable)
289 		cmd = PHY_FUNC_LINK_RESET;
290 	else
291 		cmd = PHY_FUNC_DISABLE;
292 
293 	if (scsi_is_sas_phy_local(phy)) {
294 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
295 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
296 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
297 		struct sas_internal *i =
298 			to_sas_internal(sas_ha->core.shost->transportt);
299 
300 		if (enable)
301 			ret = transport_sas_phy_reset(phy, 0);
302 		else
303 			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
304 	} else {
305 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
306 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
307 
308 		if (enable)
309 			ret = transport_sas_phy_reset(phy, 0);
310 		else
311 			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
312 	}
313 	return ret;
314 }
315 
316 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
317 {
318 	int ret;
319 	enum phy_func reset_type;
320 
321 	if (!phy->enabled)
322 		return -ENODEV;
323 
324 	if (hard_reset)
325 		reset_type = PHY_FUNC_HARD_RESET;
326 	else
327 		reset_type = PHY_FUNC_LINK_RESET;
328 
329 	if (scsi_is_sas_phy_local(phy)) {
330 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
331 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
332 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
333 		struct sas_internal *i =
334 			to_sas_internal(sas_ha->core.shost->transportt);
335 
336 		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
337 	} else {
338 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
339 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
340 		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
341 	}
342 	return ret;
343 }
344 
345 int sas_set_phy_speed(struct sas_phy *phy,
346 		      struct sas_phy_linkrates *rates)
347 {
348 	int ret;
349 
350 	if ((rates->minimum_linkrate &&
351 	     rates->minimum_linkrate > phy->maximum_linkrate) ||
352 	    (rates->maximum_linkrate &&
353 	     rates->maximum_linkrate < phy->minimum_linkrate))
354 		return -EINVAL;
355 
356 	if (rates->minimum_linkrate &&
357 	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
358 		rates->minimum_linkrate = phy->minimum_linkrate_hw;
359 
360 	if (rates->maximum_linkrate &&
361 	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
362 		rates->maximum_linkrate = phy->maximum_linkrate_hw;
363 
364 	if (scsi_is_sas_phy_local(phy)) {
365 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
366 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
367 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
368 		struct sas_internal *i =
369 			to_sas_internal(sas_ha->core.shost->transportt);
370 
371 		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
372 					       rates);
373 	} else {
374 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
375 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
376 		ret = sas_smp_phy_control(ddev, phy->number,
377 					  PHY_FUNC_LINK_RESET, rates);
378 
379 	}
380 
381 	return ret;
382 }
383 
384 static void sas_phy_release(struct sas_phy *phy)
385 {
386 	kfree(phy->hostdata);
387 	phy->hostdata = NULL;
388 }
389 
390 static void phy_reset_work(struct work_struct *work)
391 {
392 	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
393 
394 	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
395 }
396 
397 static void phy_enable_work(struct work_struct *work)
398 {
399 	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
400 
401 	d->enable_result = sas_phy_enable(d->phy, d->enable);
402 }
403 
404 static int sas_phy_setup(struct sas_phy *phy)
405 {
406 	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
407 
408 	if (!d)
409 		return -ENOMEM;
410 
411 	mutex_init(&d->event_lock);
412 	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
413 	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
414 	d->phy = phy;
415 	phy->hostdata = d;
416 
417 	return 0;
418 }
419 
420 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
421 {
422 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
423 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
424 	struct sas_phy_data *d = phy->hostdata;
425 	int rc;
426 
427 	if (!d)
428 		return -ENOMEM;
429 
430 	/* libsas workqueue coordinates ata-eh reset with discovery */
431 	mutex_lock(&d->event_lock);
432 	d->reset_result = 0;
433 	d->hard_reset = hard_reset;
434 
435 	spin_lock_irq(&ha->lock);
436 	sas_queue_work(ha, &d->reset_work);
437 	spin_unlock_irq(&ha->lock);
438 
439 	rc = sas_drain_work(ha);
440 	if (rc == 0)
441 		rc = d->reset_result;
442 	mutex_unlock(&d->event_lock);
443 
444 	return rc;
445 }
446 
447 static int queue_phy_enable(struct sas_phy *phy, int enable)
448 {
449 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
450 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
451 	struct sas_phy_data *d = phy->hostdata;
452 	int rc;
453 
454 	if (!d)
455 		return -ENOMEM;
456 
457 	/* libsas workqueue coordinates ata-eh reset with discovery */
458 	mutex_lock(&d->event_lock);
459 	d->enable_result = 0;
460 	d->enable = enable;
461 
462 	spin_lock_irq(&ha->lock);
463 	sas_queue_work(ha, &d->enable_work);
464 	spin_unlock_irq(&ha->lock);
465 
466 	rc = sas_drain_work(ha);
467 	if (rc == 0)
468 		rc = d->enable_result;
469 	mutex_unlock(&d->event_lock);
470 
471 	return rc;
472 }
473 
474 static struct sas_function_template sft = {
475 	.phy_enable = queue_phy_enable,
476 	.phy_reset = queue_phy_reset,
477 	.phy_setup = sas_phy_setup,
478 	.phy_release = sas_phy_release,
479 	.set_phy_speed = sas_set_phy_speed,
480 	.get_linkerrors = sas_get_linkerrors,
481 	.smp_handler = sas_smp_handler,
482 };
483 
484 struct scsi_transport_template *
485 sas_domain_attach_transport(struct sas_domain_function_template *dft)
486 {
487 	struct scsi_transport_template *stt = sas_attach_transport(&sft);
488 	struct sas_internal *i;
489 
490 	if (!stt)
491 		return stt;
492 
493 	i = to_sas_internal(stt);
494 	i->dft = dft;
495 	stt->create_work_queue = 1;
496 	stt->eh_timed_out = sas_scsi_timed_out;
497 	stt->eh_strategy_handler = sas_scsi_recover_host;
498 
499 	return stt;
500 }
501 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
502 
503 
504 void sas_domain_release_transport(struct scsi_transport_template *stt)
505 {
506 	sas_release_transport(stt);
507 }
508 EXPORT_SYMBOL_GPL(sas_domain_release_transport);
509 
510 /* ---------- SAS Class register/unregister ---------- */
511 
512 static int __init sas_class_init(void)
513 {
514 	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
515 	if (!sas_task_cache)
516 		return -ENOMEM;
517 
518 	return 0;
519 }
520 
521 static void __exit sas_class_exit(void)
522 {
523 	kmem_cache_destroy(sas_task_cache);
524 }
525 
526 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
527 MODULE_DESCRIPTION("SAS Transport Layer");
528 MODULE_LICENSE("GPL v2");
529 
530 module_init(sas_class_init);
531 module_exit(sas_class_exit);
532 
533 EXPORT_SYMBOL_GPL(sas_register_ha);
534 EXPORT_SYMBOL_GPL(sas_unregister_ha);
535