xref: /openbmc/linux/drivers/s390/cio/device_ops.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  *  drivers/s390/cio/device_ops.c
3  *
4  *   $Revision: 1.55 $
5  *
6  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
7  *			 IBM Corporation
8  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
9  *               Cornelia Huck (cohuck@de.ibm.com)
10  */
11 #include <linux/config.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/list.h>
17 #include <linux/device.h>
18 #include <linux/delay.h>
19 
20 #include <asm/ccwdev.h>
21 #include <asm/idals.h>
22 #include <asm/qdio.h>
23 
24 #include "cio.h"
25 #include "cio_debug.h"
26 #include "css.h"
27 #include "chsc.h"
28 #include "device.h"
29 #include "qdio.h"
30 
31 int
32 ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
33 {
34        /*
35 	* The flag usage is mutal exclusive ...
36 	*/
37 	if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
38 	    (flags & CCWDEV_REPORT_ALL))
39 		return -EINVAL;
40 	cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
41 	cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
42 	cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
43 	cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
44 	return 0;
45 }
46 
47 int
48 ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
49 {
50 	struct subchannel *sch;
51 	int ret;
52 
53 	if (!cdev)
54 		return -ENODEV;
55 	if (cdev->private->state == DEV_STATE_NOT_OPER)
56 		return -ENODEV;
57 	if (cdev->private->state != DEV_STATE_ONLINE &&
58 	    cdev->private->state != DEV_STATE_WAIT4IO &&
59 	    cdev->private->state != DEV_STATE_W4SENSE)
60 		return -EINVAL;
61 	sch = to_subchannel(cdev->dev.parent);
62 	if (!sch)
63 		return -ENODEV;
64 	ret = cio_clear(sch);
65 	if (ret == 0)
66 		cdev->private->intparm = intparm;
67 	return ret;
68 }
69 
70 int
71 ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
72 		     unsigned long intparm, __u8 lpm, __u8 key,
73 		     unsigned long flags)
74 {
75 	struct subchannel *sch;
76 	int ret;
77 
78 	if (!cdev)
79 		return -ENODEV;
80 	sch = to_subchannel(cdev->dev.parent);
81 	if (!sch)
82 		return -ENODEV;
83 	if (cdev->private->state == DEV_STATE_NOT_OPER)
84 		return -ENODEV;
85 	if (cdev->private->state == DEV_STATE_VERIFY) {
86 		/* Remember to fake irb when finished. */
87 		if (!cdev->private->flags.fake_irb) {
88 			cdev->private->flags.fake_irb = 1;
89 			cdev->private->intparm = intparm;
90 			return 0;
91 		} else
92 			/* There's already a fake I/O around. */
93 			return -EBUSY;
94 	}
95 	if (cdev->private->state != DEV_STATE_ONLINE ||
96 	    ((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
97 	     !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
98 	    cdev->private->flags.doverify)
99 		return -EBUSY;
100 	ret = cio_set_options (sch, flags);
101 	if (ret)
102 		return ret;
103 	ret = cio_start_key (sch, cpa, lpm, key);
104 	if (ret == 0)
105 		cdev->private->intparm = intparm;
106 	return ret;
107 }
108 
109 
110 int
111 ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
112 			     unsigned long intparm, __u8 lpm, __u8 key,
113 			     unsigned long flags, int expires)
114 {
115 	int ret;
116 
117 	if (!cdev)
118 		return -ENODEV;
119 	ccw_device_set_timeout(cdev, expires);
120 	ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
121 	if (ret != 0)
122 		ccw_device_set_timeout(cdev, 0);
123 	return ret;
124 }
125 
126 int
127 ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
128 		 unsigned long intparm, __u8 lpm, unsigned long flags)
129 {
130 	return ccw_device_start_key(cdev, cpa, intparm, lpm,
131 				    default_storage_key, flags);
132 }
133 
134 int
135 ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
136 			 unsigned long intparm, __u8 lpm, unsigned long flags,
137 			 int expires)
138 {
139 	return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm,
140 					    default_storage_key, flags,
141 					    expires);
142 }
143 
144 
145 int
146 ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
147 {
148 	struct subchannel *sch;
149 	int ret;
150 
151 	if (!cdev)
152 		return -ENODEV;
153 	if (cdev->private->state == DEV_STATE_NOT_OPER)
154 		return -ENODEV;
155 	if (cdev->private->state != DEV_STATE_ONLINE &&
156 	    cdev->private->state != DEV_STATE_WAIT4IO &&
157 	    cdev->private->state != DEV_STATE_W4SENSE)
158 		return -EINVAL;
159 	sch = to_subchannel(cdev->dev.parent);
160 	if (!sch)
161 		return -ENODEV;
162 	ret = cio_halt(sch);
163 	if (ret == 0)
164 		cdev->private->intparm = intparm;
165 	return ret;
166 }
167 
168 int
169 ccw_device_resume(struct ccw_device *cdev)
170 {
171 	struct subchannel *sch;
172 
173 	if (!cdev)
174 		return -ENODEV;
175 	sch = to_subchannel(cdev->dev.parent);
176 	if (!sch)
177 		return -ENODEV;
178 	if (cdev->private->state == DEV_STATE_NOT_OPER)
179 		return -ENODEV;
180 	if (cdev->private->state != DEV_STATE_ONLINE ||
181 	    !(sch->schib.scsw.actl & SCSW_ACTL_SUSPENDED))
182 		return -EINVAL;
183 	return cio_resume(sch);
184 }
185 
186 /*
187  * Pass interrupt to device driver.
188  */
189 int
190 ccw_device_call_handler(struct ccw_device *cdev)
191 {
192 	struct subchannel *sch;
193 	unsigned int stctl;
194 	int ending_status;
195 
196 	sch = to_subchannel(cdev->dev.parent);
197 
198 	/*
199 	 * we allow for the device action handler if .
200 	 *  - we received ending status
201 	 *  - the action handler requested to see all interrupts
202 	 *  - we received an intermediate status
203 	 *  - fast notification was requested (primary status)
204 	 *  - unsolicited interrupts
205 	 */
206 	stctl = cdev->private->irb.scsw.stctl;
207 	ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
208 		(stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
209 		(stctl == SCSW_STCTL_STATUS_PEND);
210 	if (!ending_status &&
211 	    !cdev->private->options.repall &&
212 	    !(stctl & SCSW_STCTL_INTER_STATUS) &&
213 	    !(cdev->private->options.fast &&
214 	      (stctl & SCSW_STCTL_PRIM_STATUS)))
215 		return 0;
216 
217 	/*
218 	 * Now we are ready to call the device driver interrupt handler.
219 	 */
220 	if (cdev->handler)
221 		cdev->handler(cdev, cdev->private->intparm,
222 			      &cdev->private->irb);
223 
224 	/*
225 	 * Clear the old and now useless interrupt response block.
226 	 */
227 	memset(&cdev->private->irb, 0, sizeof(struct irb));
228 
229 	return 1;
230 }
231 
232 /*
233  * Search for CIW command in extended sense data.
234  */
235 struct ciw *
236 ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
237 {
238 	int ciw_cnt;
239 
240 	if (cdev->private->flags.esid == 0)
241 		return NULL;
242 	for (ciw_cnt = 0; ciw_cnt < MAX_CIWS; ciw_cnt++)
243 		if (cdev->private->senseid.ciw[ciw_cnt].ct == ct)
244 			return cdev->private->senseid.ciw + ciw_cnt;
245 	return NULL;
246 }
247 
248 __u8
249 ccw_device_get_path_mask(struct ccw_device *cdev)
250 {
251 	struct subchannel *sch;
252 
253 	sch = to_subchannel(cdev->dev.parent);
254 	if (!sch)
255 		return 0;
256 	else
257 		return sch->vpm;
258 }
259 
260 static void
261 ccw_device_wake_up(struct ccw_device *cdev, unsigned long ip, struct irb *irb)
262 {
263 	if (!ip)
264 		/* unsolicited interrupt */
265 		return;
266 
267 	/* Abuse intparm for error reporting. */
268 	if (IS_ERR(irb))
269 		cdev->private->intparm = -EIO;
270 	else if ((irb->scsw.dstat !=
271 		  (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
272 		 (irb->scsw.cstat != 0)) {
273 		/*
274 		 * We didn't get channel end / device end. Check if path
275 		 * verification has been started; we can retry after it has
276 		 * finished. We also retry unit checks except for command reject
277 		 * or intervention required.
278 		 */
279 		 if (cdev->private->flags.doverify ||
280 			 cdev->private->state == DEV_STATE_VERIFY)
281 			 cdev->private->intparm = -EAGAIN;
282 		 if ((irb->scsw.dstat & DEV_STAT_UNIT_CHECK) &&
283 		     !(irb->ecw[0] &
284 		       (SNS0_CMD_REJECT | SNS0_INTERVENTION_REQ)))
285 			 cdev->private->intparm = -EAGAIN;
286 		 else
287 			 cdev->private->intparm = -EIO;
288 
289 	} else
290 		cdev->private->intparm = 0;
291 	wake_up(&cdev->private->wait_q);
292 }
293 
294 static inline int
295 __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, __u8 lpm)
296 {
297 	int ret;
298 	struct subchannel *sch;
299 
300 	sch = to_subchannel(cdev->dev.parent);
301 	do {
302 		ret = cio_start (sch, ccw, lpm);
303 		if ((ret == -EBUSY) || (ret == -EACCES)) {
304 			/* Try again later. */
305 			spin_unlock_irq(&sch->lock);
306 			msleep(10);
307 			spin_lock_irq(&sch->lock);
308 			continue;
309 		}
310 		if (ret != 0)
311 			/* Non-retryable error. */
312 			break;
313 		/* Wait for end of request. */
314 		cdev->private->intparm = magic;
315 		spin_unlock_irq(&sch->lock);
316 		wait_event(cdev->private->wait_q,
317 			   (cdev->private->intparm == -EIO) ||
318 			   (cdev->private->intparm == -EAGAIN) ||
319 			   (cdev->private->intparm == 0));
320 		spin_lock_irq(&sch->lock);
321 		/* Check at least for channel end / device end */
322 		if (cdev->private->intparm == -EIO) {
323 			/* Non-retryable error. */
324 			ret = -EIO;
325 			break;
326 		}
327 		if (cdev->private->intparm == 0)
328 			/* Success. */
329 			break;
330 		/* Try again later. */
331 		spin_unlock_irq(&sch->lock);
332 		msleep(10);
333 		spin_lock_irq(&sch->lock);
334 	} while (1);
335 
336 	return ret;
337 }
338 
339 /**
340  * read_dev_chars() - read device characteristics
341  * @param cdev   target ccw device
342  * @param buffer pointer to buffer for rdc data
343  * @param length size of rdc data
344  * @returns 0 for success, negative error value on failure
345  *
346  * Context:
347  *   called for online device, lock not held
348  **/
349 int
350 read_dev_chars (struct ccw_device *cdev, void **buffer, int length)
351 {
352 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
353 	struct subchannel *sch;
354 	int ret;
355 	struct ccw1 *rdc_ccw;
356 
357 	if (!cdev)
358 		return -ENODEV;
359 	if (!buffer || !length)
360 		return -EINVAL;
361 	sch = to_subchannel(cdev->dev.parent);
362 
363 	CIO_TRACE_EVENT (4, "rddevch");
364 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
365 
366 	rdc_ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
367 	if (!rdc_ccw)
368 		return -ENOMEM;
369 	memset(rdc_ccw, 0, sizeof(struct ccw1));
370 	rdc_ccw->cmd_code = CCW_CMD_RDC;
371 	rdc_ccw->count = length;
372 	rdc_ccw->flags = CCW_FLAG_SLI;
373 	ret = set_normalized_cda (rdc_ccw, (*buffer));
374 	if (ret != 0) {
375 		kfree(rdc_ccw);
376 		return ret;
377 	}
378 
379 	spin_lock_irq(&sch->lock);
380 	/* Save interrupt handler. */
381 	handler = cdev->handler;
382 	/* Temporarily install own handler. */
383 	cdev->handler = ccw_device_wake_up;
384 	if (cdev->private->state != DEV_STATE_ONLINE)
385 		ret = -ENODEV;
386 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
387 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
388 		 cdev->private->flags.doverify)
389 		ret = -EBUSY;
390 	else
391 		/* 0x00D9C4C3 == ebcdic "RDC" */
392 		ret = __ccw_device_retry_loop(cdev, rdc_ccw, 0x00D9C4C3, 0);
393 
394 	/* Restore interrupt handler. */
395 	cdev->handler = handler;
396 	spin_unlock_irq(&sch->lock);
397 
398 	clear_normalized_cda (rdc_ccw);
399 	kfree(rdc_ccw);
400 
401 	return ret;
402 }
403 
404 /*
405  *  Read Configuration data using path mask
406  */
407 int
408 read_conf_data_lpm (struct ccw_device *cdev, void **buffer, int *length, __u8 lpm)
409 {
410 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
411 	struct subchannel *sch;
412 	struct ciw *ciw;
413 	char *rcd_buf;
414 	int ret;
415 	struct ccw1 *rcd_ccw;
416 
417 	if (!cdev)
418 		return -ENODEV;
419 	if (!buffer || !length)
420 		return -EINVAL;
421 	sch = to_subchannel(cdev->dev.parent);
422 
423 	CIO_TRACE_EVENT (4, "rdconf");
424 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
425 
426 	/*
427 	 * scan for RCD command in extended SenseID data
428 	 */
429 	ciw = ccw_device_get_ciw(cdev, CIW_TYPE_RCD);
430 	if (!ciw || ciw->cmd == 0)
431 		return -EOPNOTSUPP;
432 
433 	rcd_ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
434 	if (!rcd_ccw)
435 		return -ENOMEM;
436 	memset(rcd_ccw, 0, sizeof(struct ccw1));
437 	rcd_buf = kmalloc(ciw->count, GFP_KERNEL | GFP_DMA);
438  	if (!rcd_buf) {
439 		kfree(rcd_ccw);
440 		return -ENOMEM;
441 	}
442  	memset (rcd_buf, 0, ciw->count);
443 	rcd_ccw->cmd_code = ciw->cmd;
444 	rcd_ccw->cda = (__u32) __pa (rcd_buf);
445 	rcd_ccw->count = ciw->count;
446 	rcd_ccw->flags = CCW_FLAG_SLI;
447 
448 	spin_lock_irq(&sch->lock);
449 	/* Save interrupt handler. */
450 	handler = cdev->handler;
451 	/* Temporarily install own handler. */
452 	cdev->handler = ccw_device_wake_up;
453 	if (cdev->private->state != DEV_STATE_ONLINE)
454 		ret = -ENODEV;
455 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
456 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
457 		 cdev->private->flags.doverify)
458 		ret = -EBUSY;
459 	else
460 		/* 0x00D9C3C4 == ebcdic "RCD" */
461 		ret = __ccw_device_retry_loop(cdev, rcd_ccw, 0x00D9C3C4, lpm);
462 
463 	/* Restore interrupt handler. */
464 	cdev->handler = handler;
465 	spin_unlock_irq(&sch->lock);
466 
467  	/*
468  	 * on success we update the user input parms
469  	 */
470  	if (ret) {
471  		kfree (rcd_buf);
472  		*buffer = NULL;
473  		*length = 0;
474  	} else {
475 		*length = ciw->count;
476 		*buffer = rcd_buf;
477 	}
478 	kfree(rcd_ccw);
479 
480 	return ret;
481 }
482 
483 /*
484  *  Read Configuration data
485  */
486 int
487 read_conf_data (struct ccw_device *cdev, void **buffer, int *length)
488 {
489 	return read_conf_data_lpm (cdev, buffer, length, 0);
490 }
491 
492 /*
493  * Try to break the lock on a boxed device.
494  */
495 int
496 ccw_device_stlck(struct ccw_device *cdev)
497 {
498 	void *buf, *buf2;
499 	unsigned long flags;
500 	struct subchannel *sch;
501 	int ret;
502 
503 	if (!cdev)
504 		return -ENODEV;
505 
506 	if (cdev->drv && !cdev->private->options.force)
507 		return -EINVAL;
508 
509 	sch = to_subchannel(cdev->dev.parent);
510 
511 	CIO_TRACE_EVENT(2, "stl lock");
512 	CIO_TRACE_EVENT(2, cdev->dev.bus_id);
513 
514 	buf = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
515 	if (!buf)
516 		return -ENOMEM;
517 	buf2 = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
518 	if (!buf2) {
519 		kfree(buf);
520 		return -ENOMEM;
521 	}
522 	spin_lock_irqsave(&sch->lock, flags);
523 	ret = cio_enable_subchannel(sch, 3);
524 	if (ret)
525 		goto out_unlock;
526 	/*
527 	 * Setup ccw. We chain an unconditional reserve and a release so we
528 	 * only break the lock.
529 	 */
530 	cdev->private->iccws[0].cmd_code = CCW_CMD_STLCK;
531 	cdev->private->iccws[0].cda = (__u32) __pa(buf);
532 	cdev->private->iccws[0].count = 32;
533 	cdev->private->iccws[0].flags = CCW_FLAG_CC;
534 	cdev->private->iccws[1].cmd_code = CCW_CMD_RELEASE;
535 	cdev->private->iccws[1].cda = (__u32) __pa(buf2);
536 	cdev->private->iccws[1].count = 32;
537 	cdev->private->iccws[1].flags = 0;
538 	ret = cio_start(sch, cdev->private->iccws, 0);
539 	if (ret) {
540 		cio_disable_subchannel(sch); //FIXME: return code?
541 		goto out_unlock;
542 	}
543 	cdev->private->irb.scsw.actl |= SCSW_ACTL_START_PEND;
544 	spin_unlock_irqrestore(&sch->lock, flags);
545 	wait_event(cdev->private->wait_q, cdev->private->irb.scsw.actl == 0);
546 	spin_lock_irqsave(&sch->lock, flags);
547 	cio_disable_subchannel(sch); //FIXME: return code?
548 	if ((cdev->private->irb.scsw.dstat !=
549 	     (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
550 	    (cdev->private->irb.scsw.cstat != 0))
551 		ret = -EIO;
552 	/* Clear irb. */
553 	memset(&cdev->private->irb, 0, sizeof(struct irb));
554 out_unlock:
555 	if (buf)
556 		kfree(buf);
557 	if (buf2)
558 		kfree(buf2);
559 	spin_unlock_irqrestore(&sch->lock, flags);
560 	return ret;
561 }
562 
563 void *
564 ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no)
565 {
566 	struct subchannel *sch;
567 
568 	sch = to_subchannel(cdev->dev.parent);
569 	return chsc_get_chp_desc(sch, chp_no);
570 }
571 
572 // FIXME: these have to go:
573 
574 int
575 _ccw_device_get_subchannel_number(struct ccw_device *cdev)
576 {
577 	return cdev->private->irq;
578 }
579 
580 int
581 _ccw_device_get_device_number(struct ccw_device *cdev)
582 {
583 	return cdev->private->devno;
584 }
585 
586 
587 MODULE_LICENSE("GPL");
588 EXPORT_SYMBOL(ccw_device_set_options);
589 EXPORT_SYMBOL(ccw_device_clear);
590 EXPORT_SYMBOL(ccw_device_halt);
591 EXPORT_SYMBOL(ccw_device_resume);
592 EXPORT_SYMBOL(ccw_device_start_timeout);
593 EXPORT_SYMBOL(ccw_device_start);
594 EXPORT_SYMBOL(ccw_device_start_timeout_key);
595 EXPORT_SYMBOL(ccw_device_start_key);
596 EXPORT_SYMBOL(ccw_device_get_ciw);
597 EXPORT_SYMBOL(ccw_device_get_path_mask);
598 EXPORT_SYMBOL(read_conf_data);
599 EXPORT_SYMBOL(read_dev_chars);
600 EXPORT_SYMBOL(_ccw_device_get_subchannel_number);
601 EXPORT_SYMBOL(_ccw_device_get_device_number);
602 EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);
603 EXPORT_SYMBOL_GPL(read_conf_data_lpm);
604