xref: /openbmc/linux/drivers/scsi/libsas/sas_init.c (revision 63dc02bd)
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 = to_sas_ha_event(work);
98 	struct sas_ha_struct *ha = ev->ha;
99 
100 	clear_bit(HAE_RESET, &ha->pending);
101 }
102 
103 int sas_register_ha(struct sas_ha_struct *sas_ha)
104 {
105 	int error = 0;
106 
107 	mutex_init(&sas_ha->disco_mutex);
108 	spin_lock_init(&sas_ha->phy_port_lock);
109 	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
110 
111 	if (sas_ha->lldd_queue_size == 0)
112 		sas_ha->lldd_queue_size = 1;
113 	else if (sas_ha->lldd_queue_size == -1)
114 		sas_ha->lldd_queue_size = 128; /* Sanity */
115 
116 	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
117 	spin_lock_init(&sas_ha->state_lock);
118 	mutex_init(&sas_ha->drain_mutex);
119 	INIT_LIST_HEAD(&sas_ha->defer_q);
120 
121 	error = sas_register_phys(sas_ha);
122 	if (error) {
123 		printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
124 		return error;
125 	}
126 
127 	error = sas_register_ports(sas_ha);
128 	if (error) {
129 		printk(KERN_NOTICE "couldn't register sas ports:%d\n", error);
130 		goto Undo_phys;
131 	}
132 
133 	error = sas_init_events(sas_ha);
134 	if (error) {
135 		printk(KERN_NOTICE "couldn't start event thread:%d\n", error);
136 		goto Undo_ports;
137 	}
138 
139 	if (sas_ha->lldd_max_execute_num > 1) {
140 		error = sas_init_queue(sas_ha);
141 		if (error) {
142 			printk(KERN_NOTICE "couldn't start queue thread:%d, "
143 			       "running in direct mode\n", error);
144 			sas_ha->lldd_max_execute_num = 1;
145 		}
146 	}
147 
148 	INIT_LIST_HEAD(&sas_ha->eh_done_q);
149 	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
150 
151 	return 0;
152 
153 Undo_ports:
154 	sas_unregister_ports(sas_ha);
155 Undo_phys:
156 
157 	return error;
158 }
159 
160 int sas_unregister_ha(struct sas_ha_struct *sas_ha)
161 {
162 	/* Set the state to unregistered to avoid further unchained
163 	 * events to be queued, and flush any in-progress drainers
164 	 */
165 	mutex_lock(&sas_ha->drain_mutex);
166 	spin_lock_irq(&sas_ha->state_lock);
167 	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
168 	spin_unlock_irq(&sas_ha->state_lock);
169 	__sas_drain_work(sas_ha);
170 	mutex_unlock(&sas_ha->drain_mutex);
171 
172 	sas_unregister_ports(sas_ha);
173 
174 	/* flush unregistration work */
175 	mutex_lock(&sas_ha->drain_mutex);
176 	__sas_drain_work(sas_ha);
177 	mutex_unlock(&sas_ha->drain_mutex);
178 
179 	if (sas_ha->lldd_max_execute_num > 1) {
180 		sas_shutdown_queue(sas_ha);
181 		sas_ha->lldd_max_execute_num = 1;
182 	}
183 
184 	return 0;
185 }
186 
187 static int sas_get_linkerrors(struct sas_phy *phy)
188 {
189 	if (scsi_is_sas_phy_local(phy)) {
190 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
191 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
192 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
193 		struct sas_internal *i =
194 			to_sas_internal(sas_ha->core.shost->transportt);
195 
196 		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
197 	}
198 
199 	return sas_smp_get_phy_events(phy);
200 }
201 
202 int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
203 {
204 	struct domain_device *dev = NULL;
205 
206 	/* try to route user requested link resets through libata */
207 	if (asd_phy->port)
208 		dev = asd_phy->port->port_dev;
209 
210 	/* validate that dev has been probed */
211 	if (dev)
212 		dev = sas_find_dev_by_rphy(dev->rphy);
213 
214 	if (dev && dev_is_sata(dev)) {
215 		sas_ata_schedule_reset(dev);
216 		sas_ata_wait_eh(dev);
217 		return 0;
218 	}
219 
220 	return -ENODEV;
221 }
222 
223 /**
224  * transport_sas_phy_reset - reset a phy and permit libata to manage the link
225  *
226  * phy reset request via sysfs in host workqueue context so we know we
227  * can block on eh and safely traverse the domain_device topology
228  */
229 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
230 {
231 	enum phy_func reset_type;
232 
233 	if (hard_reset)
234 		reset_type = PHY_FUNC_HARD_RESET;
235 	else
236 		reset_type = PHY_FUNC_LINK_RESET;
237 
238 	if (scsi_is_sas_phy_local(phy)) {
239 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
240 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
241 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
242 		struct sas_internal *i =
243 			to_sas_internal(sas_ha->core.shost->transportt);
244 
245 		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
246 			return 0;
247 		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
248 	} else {
249 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
250 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
251 		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
252 
253 		if (ata_dev && !hard_reset) {
254 			sas_ata_schedule_reset(ata_dev);
255 			sas_ata_wait_eh(ata_dev);
256 			return 0;
257 		} else
258 			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
259 	}
260 }
261 
262 static int sas_phy_enable(struct sas_phy *phy, int enable)
263 {
264 	int ret;
265 	enum phy_func cmd;
266 
267 	if (enable)
268 		cmd = PHY_FUNC_LINK_RESET;
269 	else
270 		cmd = PHY_FUNC_DISABLE;
271 
272 	if (scsi_is_sas_phy_local(phy)) {
273 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
274 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
275 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
276 		struct sas_internal *i =
277 			to_sas_internal(sas_ha->core.shost->transportt);
278 
279 		if (enable)
280 			ret = transport_sas_phy_reset(phy, 0);
281 		else
282 			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
283 	} else {
284 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
285 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
286 
287 		if (enable)
288 			ret = transport_sas_phy_reset(phy, 0);
289 		else
290 			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
291 	}
292 	return ret;
293 }
294 
295 int sas_phy_reset(struct sas_phy *phy, int hard_reset)
296 {
297 	int ret;
298 	enum phy_func reset_type;
299 
300 	if (!phy->enabled)
301 		return -ENODEV;
302 
303 	if (hard_reset)
304 		reset_type = PHY_FUNC_HARD_RESET;
305 	else
306 		reset_type = PHY_FUNC_LINK_RESET;
307 
308 	if (scsi_is_sas_phy_local(phy)) {
309 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
310 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
311 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
312 		struct sas_internal *i =
313 			to_sas_internal(sas_ha->core.shost->transportt);
314 
315 		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
316 	} else {
317 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
318 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
319 		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
320 	}
321 	return ret;
322 }
323 
324 int sas_set_phy_speed(struct sas_phy *phy,
325 		      struct sas_phy_linkrates *rates)
326 {
327 	int ret;
328 
329 	if ((rates->minimum_linkrate &&
330 	     rates->minimum_linkrate > phy->maximum_linkrate) ||
331 	    (rates->maximum_linkrate &&
332 	     rates->maximum_linkrate < phy->minimum_linkrate))
333 		return -EINVAL;
334 
335 	if (rates->minimum_linkrate &&
336 	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
337 		rates->minimum_linkrate = phy->minimum_linkrate_hw;
338 
339 	if (rates->maximum_linkrate &&
340 	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
341 		rates->maximum_linkrate = phy->maximum_linkrate_hw;
342 
343 	if (scsi_is_sas_phy_local(phy)) {
344 		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
345 		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
346 		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
347 		struct sas_internal *i =
348 			to_sas_internal(sas_ha->core.shost->transportt);
349 
350 		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
351 					       rates);
352 	} else {
353 		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
354 		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
355 		ret = sas_smp_phy_control(ddev, phy->number,
356 					  PHY_FUNC_LINK_RESET, rates);
357 
358 	}
359 
360 	return ret;
361 }
362 
363 static void sas_phy_release(struct sas_phy *phy)
364 {
365 	kfree(phy->hostdata);
366 	phy->hostdata = NULL;
367 }
368 
369 static void phy_reset_work(struct work_struct *work)
370 {
371 	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
372 
373 	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
374 }
375 
376 static void phy_enable_work(struct work_struct *work)
377 {
378 	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
379 
380 	d->enable_result = sas_phy_enable(d->phy, d->enable);
381 }
382 
383 static int sas_phy_setup(struct sas_phy *phy)
384 {
385 	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
386 
387 	if (!d)
388 		return -ENOMEM;
389 
390 	mutex_init(&d->event_lock);
391 	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
392 	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
393 	d->phy = phy;
394 	phy->hostdata = d;
395 
396 	return 0;
397 }
398 
399 static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
400 {
401 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
402 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
403 	struct sas_phy_data *d = phy->hostdata;
404 	int rc;
405 
406 	if (!d)
407 		return -ENOMEM;
408 
409 	/* libsas workqueue coordinates ata-eh reset with discovery */
410 	mutex_lock(&d->event_lock);
411 	d->reset_result = 0;
412 	d->hard_reset = hard_reset;
413 
414 	spin_lock_irq(&ha->state_lock);
415 	sas_queue_work(ha, &d->reset_work);
416 	spin_unlock_irq(&ha->state_lock);
417 
418 	rc = sas_drain_work(ha);
419 	if (rc == 0)
420 		rc = d->reset_result;
421 	mutex_unlock(&d->event_lock);
422 
423 	return rc;
424 }
425 
426 static int queue_phy_enable(struct sas_phy *phy, int enable)
427 {
428 	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
429 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
430 	struct sas_phy_data *d = phy->hostdata;
431 	int rc;
432 
433 	if (!d)
434 		return -ENOMEM;
435 
436 	/* libsas workqueue coordinates ata-eh reset with discovery */
437 	mutex_lock(&d->event_lock);
438 	d->enable_result = 0;
439 	d->enable = enable;
440 
441 	spin_lock_irq(&ha->state_lock);
442 	sas_queue_work(ha, &d->enable_work);
443 	spin_unlock_irq(&ha->state_lock);
444 
445 	rc = sas_drain_work(ha);
446 	if (rc == 0)
447 		rc = d->enable_result;
448 	mutex_unlock(&d->event_lock);
449 
450 	return rc;
451 }
452 
453 static struct sas_function_template sft = {
454 	.phy_enable = queue_phy_enable,
455 	.phy_reset = queue_phy_reset,
456 	.phy_setup = sas_phy_setup,
457 	.phy_release = sas_phy_release,
458 	.set_phy_speed = sas_set_phy_speed,
459 	.get_linkerrors = sas_get_linkerrors,
460 	.smp_handler = sas_smp_handler,
461 };
462 
463 struct scsi_transport_template *
464 sas_domain_attach_transport(struct sas_domain_function_template *dft)
465 {
466 	struct scsi_transport_template *stt = sas_attach_transport(&sft);
467 	struct sas_internal *i;
468 
469 	if (!stt)
470 		return stt;
471 
472 	i = to_sas_internal(stt);
473 	i->dft = dft;
474 	stt->create_work_queue = 1;
475 	stt->eh_timed_out = sas_scsi_timed_out;
476 	stt->eh_strategy_handler = sas_scsi_recover_host;
477 
478 	return stt;
479 }
480 EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
481 
482 
483 void sas_domain_release_transport(struct scsi_transport_template *stt)
484 {
485 	sas_release_transport(stt);
486 }
487 EXPORT_SYMBOL_GPL(sas_domain_release_transport);
488 
489 /* ---------- SAS Class register/unregister ---------- */
490 
491 static int __init sas_class_init(void)
492 {
493 	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
494 	if (!sas_task_cache)
495 		return -ENOMEM;
496 
497 	return 0;
498 }
499 
500 static void __exit sas_class_exit(void)
501 {
502 	kmem_cache_destroy(sas_task_cache);
503 }
504 
505 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
506 MODULE_DESCRIPTION("SAS Transport Layer");
507 MODULE_LICENSE("GPL v2");
508 
509 module_init(sas_class_init);
510 module_exit(sas_class_exit);
511 
512 EXPORT_SYMBOL_GPL(sas_register_ha);
513 EXPORT_SYMBOL_GPL(sas_unregister_ha);
514