xref: /openbmc/linux/drivers/scsi/libsas/sas_init.c (revision e75d660672ddd11704b7f0fdb8ff21968587b266)
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 		init_timer(&task->timer);
52 		init_completion(&task->completion);
53 	}
54 
55 	return task;
56 }
57 EXPORT_SYMBOL_GPL(sas_alloc_task);
58 
59 void sas_free_task(struct sas_task *task)
60 {
61 	if (task) {
62 		BUG_ON(!list_empty(&task->list));
63 		kmem_cache_free(sas_task_cache, task);
64 	}
65 }
66 EXPORT_SYMBOL_GPL(sas_free_task);
67 
68 /*------------ SAS addr hash -----------*/
69 void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
70 {
71         const u32 poly = 0x00DB2777;
72         u32     r = 0;
73         int     i;
74 
75         for (i = 0; i < 8; i++) {
76                 int b;
77                 for (b = 7; b >= 0; b--) {
78                         r <<= 1;
79                         if ((1 << b) & sas_addr[i]) {
80                                 if (!(r & 0x01000000))
81                                         r ^= poly;
82                         } else if (r & 0x01000000)
83                                 r ^= poly;
84                 }
85         }
86 
87         hashed[0] = (r >> 16) & 0xFF;
88         hashed[1] = (r >> 8) & 0xFF ;
89         hashed[2] = r & 0xFF;
90 }
91 
92 
93 /* ---------- HA events ---------- */
94 
95 void sas_hae_reset(struct work_struct *work)
96 {
97 	struct sas_ha_event *ev =
98 		container_of(work, struct sas_ha_event, work);
99 	struct sas_ha_struct *ha = ev->ha;
100 
101 	clear_bit(HAE_RESET, &ha->pending);
102 }
103 
104 int sas_register_ha(struct sas_ha_struct *sas_ha)
105 {
106 	int error = 0;
107 
108 	mutex_init(&sas_ha->disco_mutex);
109 	spin_lock_init(&sas_ha->phy_port_lock);
110 	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
111 
112 	if (sas_ha->lldd_queue_size == 0)
113 		sas_ha->lldd_queue_size = 1;
114 	else if (sas_ha->lldd_queue_size == -1)
115 		sas_ha->lldd_queue_size = 128; /* Sanity */
116 
117 	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
118 	spin_lock_init(&sas_ha->state_lock);
119 	mutex_init(&sas_ha->drain_mutex);
120 	INIT_LIST_HEAD(&sas_ha->defer_q);
121 
122 	error = sas_register_phys(sas_ha);
123 	if (error) {
124 		printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
125 		return error;
126 	}
127 
128 	error = sas_register_ports(sas_ha);
129 	if (error) {
130 		printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
131 		goto Undo_phys;
132 	}
133 
134 	error = sas_init_events(sas_ha);
135 	if (error) {
136 		printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
137 		goto Undo_ports;
138 	}
139 
140 	if (sas_ha->lldd_max_execute_num > 1) {
141 		error = sas_init_queue(sas_ha);
142 		if (error) {
143 			printk(KERN_NOTICE "couldn't start queue thread:%d, "
144 			       "running in direct mode\n", error);
145 			sas_ha->lldd_max_execute_num = 1;
146 		}
147 	}
148 
149 	INIT_LIST_HEAD(&sas_ha->eh_done_q);
150 	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
151 
152 	return 0;
153 
154 Undo_ports:
155 	sas_unregister_ports(sas_ha);
156 Undo_phys:
157 
158 	return error;
159 }
160 
161 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
162 {
163 	/* Set the state to unregistered to avoid further unchained
164 	 * events to be queued, and flush any in-progress drainers
165 	 */
166 	mutex_lock(&sas_ha->drain_mutex);
167 	spin_lock_irq(&sas_ha->state_lock);
168 	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
169 	spin_unlock_irq(&sas_ha->state_lock);
170 	__sas_drain_work(sas_ha);
171 	mutex_unlock(&sas_ha->drain_mutex);
172 
173 	sas_unregister_ports(sas_ha);
174 
175 	/* flush unregistration work */
176 	mutex_lock(&sas_ha->drain_mutex);
177 	__sas_drain_work(sas_ha);
178 	mutex_unlock(&sas_ha->drain_mutex);
179 
180 	if (sas_ha->lldd_max_execute_num > 1) {
181 		sas_shutdown_queue(sas_ha);
182 		sas_ha->lldd_max_execute_num = 1;
183 	}
184 
185 	return 0;
186 }
187 
188 static int sas_get_linkerrors(struct sas_phy *phy)
189 {
190 	if (scsi_is_sas_phy_local(phy)) {
191 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
192 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
193 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
194 		struct sas_internal *i =
195 			to_sas_internal(sas_ha->core.shost->transportt);
196 
197 		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
198 	}
199 
200 	return sas_smp_get_phy_events(phy);
201 }
202 
203 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
204 {
205 	struct domain_device *dev = NULL;
206 
207 	/* try to route user requested link resets through libata */
208 	if (asd_phy->port)
209 		dev = asd_phy->port->port_dev;
210 
211 	/* validate that dev has been probed */
212 	if (dev)
213 		dev = sas_find_dev_by_rphy(dev->rphy);
214 
215 	if (dev && dev_is_sata(dev)) {
216 		sas_ata_schedule_reset(dev);
217 		sas_ata_wait_eh(dev);
218 		return 0;
219 	}
220 
221 	return -ENODEV;
222 }
223 
224 /**
225  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
226  *
227  * phy reset request via sysfs in host workqueue context so we know we
228  * can block on eh and safely traverse the domain_device topology
229  */
230 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
231 {
232 	enum phy_func reset_type;
233 
234 	if (hard_reset)
235 		reset_type = PHY_FUNC_HARD_RESET;
236 	else
237 		reset_type = PHY_FUNC_LINK_RESET;
238 
239 	if (scsi_is_sas_phy_local(phy)) {
240 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
241 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
242 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
243 		struct sas_internal *i =
244 			to_sas_internal(sas_ha->core.shost->transportt);
245 
246 		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
247 			return 0;
248 		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
249 	} else {
250 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
251 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
252 		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
253 
254 		if (ata_dev && !hard_reset) {
255 			sas_ata_schedule_reset(ata_dev);
256 			sas_ata_wait_eh(ata_dev);
257 			return 0;
258 		} else
259 			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
260 	}
261 }
262 
263 static int sas_phy_enable(struct sas_phy *phy, int enable)
264 {
265 	int ret;
266 	enum phy_func cmd;
267 
268 	if (enable)
269 		cmd = PHY_FUNC_LINK_RESET;
270 	else
271 		cmd = PHY_FUNC_DISABLE;
272 
273 	if (scsi_is_sas_phy_local(phy)) {
274 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
275 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
276 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
277 		struct sas_internal *i =
278 			to_sas_internal(sas_ha->core.shost->transportt);
279 
280 		if (enable)
281 			ret = transport_sas_phy_reset(phy, 0);
282 		else
283 			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
284 	} else {
285 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
286 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
287 
288 		if (enable)
289 			ret = transport_sas_phy_reset(phy, 0);
290 		else
291 			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
292 	}
293 	return ret;
294 }
295 
296 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
297 {
298 	int ret;
299 	enum phy_func reset_type;
300 
301 	if (!phy->enabled)
302 		return -ENODEV;
303 
304 	if (hard_reset)
305 		reset_type = PHY_FUNC_HARD_RESET;
306 	else
307 		reset_type = PHY_FUNC_LINK_RESET;
308 
309 	if (scsi_is_sas_phy_local(phy)) {
310 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
311 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
312 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
313 		struct sas_internal *i =
314 			to_sas_internal(sas_ha->core.shost->transportt);
315 
316 		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
317 	} else {
318 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
319 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
320 		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
321 	}
322 	return ret;
323 }
324 
325 int sas_set_phy_speed(struct sas_phy *phy,
326 		      struct sas_phy_linkrates *rates)
327 {
328 	int ret;
329 
330 	if ((rates->minimum_linkrate &&
331 	     rates->minimum_linkrate > phy->maximum_linkrate) ||
332 	    (rates->maximum_linkrate &&
333 	     rates->maximum_linkrate < phy->minimum_linkrate))
334 		return -EINVAL;
335 
336 	if (rates->minimum_linkrate &&
337 	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
338 		rates->minimum_linkrate = phy->minimum_linkrate_hw;
339 
340 	if (rates->maximum_linkrate &&
341 	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
342 		rates->maximum_linkrate = phy->maximum_linkrate_hw;
343 
344 	if (scsi_is_sas_phy_local(phy)) {
345 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
346 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
347 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
348 		struct sas_internal *i =
349 			to_sas_internal(sas_ha->core.shost->transportt);
350 
351 		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
352 					       rates);
353 	} else {
354 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
355 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
356 		ret = sas_smp_phy_control(ddev, phy->number,
357 					  PHY_FUNC_LINK_RESET, rates);
358 
359 	}
360 
361 	return ret;
362 }
363 
364 static void sas_phy_release(struct sas_phy *phy)
365 {
366 	kfree(phy->hostdata);
367 	phy->hostdata = NULL;
368 }
369 
370 static void phy_reset_work(struct work_struct *work)
371 {
372 	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work);
373 
374 	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
375 }
376 
377 static void phy_enable_work(struct work_struct *work)
378 {
379 	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work);
380 
381 	d->enable_result = sas_phy_enable(d->phy, d->enable);
382 }
383 
384 static int sas_phy_setup(struct sas_phy *phy)
385 {
386 	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
387 
388 	if (!d)
389 		return -ENOMEM;
390 
391 	mutex_init(&d->event_lock);
392 	INIT_WORK(&d->reset_work, phy_reset_work);
393 	INIT_WORK(&d->enable_work, phy_enable_work);
394 	d->phy = phy;
395 	phy->hostdata = d;
396 
397 	return 0;
398 }
399 
400 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
401 {
402 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
403 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
404 	struct sas_phy_data *d = phy->hostdata;
405 	int rc;
406 
407 	if (!d)
408 		return -ENOMEM;
409 
410 	/* libsas workqueue coordinates ata-eh reset with discovery */
411 	mutex_lock(&d->event_lock);
412 	d->reset_result = 0;
413 	d->hard_reset = hard_reset;
414 
415 	spin_lock_irq(&ha->state_lock);
416 	sas_queue_work(ha, &d->reset_work);
417 	spin_unlock_irq(&ha->state_lock);
418 
419 	rc = sas_drain_work(ha);
420 	if (rc == 0)
421 		rc = d->reset_result;
422 	mutex_unlock(&d->event_lock);
423 
424 	return rc;
425 }
426 
427 static int queue_phy_enable(struct sas_phy *phy, int enable)
428 {
429 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
430 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
431 	struct sas_phy_data *d = phy->hostdata;
432 	int rc;
433 
434 	if (!d)
435 		return -ENOMEM;
436 
437 	/* libsas workqueue coordinates ata-eh reset with discovery */
438 	mutex_lock(&d->event_lock);
439 	d->enable_result = 0;
440 	d->enable = enable;
441 
442 	spin_lock_irq(&ha->state_lock);
443 	sas_queue_work(ha, &d->enable_work);
444 	spin_unlock_irq(&ha->state_lock);
445 
446 	rc = sas_drain_work(ha);
447 	if (rc == 0)
448 		rc = d->enable_result;
449 	mutex_unlock(&d->event_lock);
450 
451 	return rc;
452 }
453 
454 static struct sas_function_template sft = {
455 	.phy_enable = queue_phy_enable,
456 	.phy_reset = queue_phy_reset,
457 	.phy_setup = sas_phy_setup,
458 	.phy_release = sas_phy_release,
459 	.set_phy_speed = sas_set_phy_speed,
460 	.get_linkerrors = sas_get_linkerrors,
461 	.smp_handler = sas_smp_handler,
462 };
463 
464 struct scsi_transport_template *
465 sas_domain_attach_transport(struct sas_domain_function_template *dft)
466 {
467 	struct scsi_transport_template *stt = sas_attach_transport(&sft);
468 	struct sas_internal *i;
469 
470 	if (!stt)
471 		return stt;
472 
473 	i = to_sas_internal(stt);
474 	i->dft = dft;
475 	stt->create_work_queue = 1;
476 	stt->eh_timed_out = sas_scsi_timed_out;
477 	stt->eh_strategy_handler = sas_scsi_recover_host;
478 
479 	return stt;
480 }
481 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
482 
483 
484 void sas_domain_release_transport(struct scsi_transport_template *stt)
485 {
486 	sas_release_transport(stt);
487 }
488 EXPORT_SYMBOL_GPL(sas_domain_release_transport);
489 
490 /* ---------- SAS Class register/unregister ---------- */
491 
492 static int __init sas_class_init(void)
493 {
494 	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
495 	if (!sas_task_cache)
496 		return -ENOMEM;
497 
498 	return 0;
499 }
500 
501 static void __exit sas_class_exit(void)
502 {
503 	kmem_cache_destroy(sas_task_cache);
504 }
505 
506 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
507 MODULE_DESCRIPTION("SAS Transport Layer");
508 MODULE_LICENSE("GPL v2");
509 
510 module_init(sas_class_init);
511 module_exit(sas_class_exit);
512 
513 EXPORT_SYMBOL_GPL(sas_register_ha);
514 EXPORT_SYMBOL_GPL(sas_unregister_ha);
515