blob: 6f274f4f92ebea21cc6003796f12bfdcb6606bfd [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * drivers/s390/cio/cio.c
3 * S/390 common I/O routines -- low level i/o calls
Cornelia Huckfb6958a2006-01-06 00:19:25 -08004 * $Revision: 1.138 $
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
6 * Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
7 * IBM Corporation
8 * Author(s): Ingo Adlung (adlung@de.ibm.com)
9 * Cornelia Huck (cohuck@de.ibm.com)
10 * Arnd Bergmann (arndb@de.ibm.com)
11 * Martin Schwidefsky (schwidefsky@de.ibm.com)
12 */
13
14#include <linux/module.h>
15#include <linux/config.h>
16#include <linux/init.h>
17#include <linux/slab.h>
18#include <linux/device.h>
19#include <linux/kernel_stat.h>
20#include <linux/interrupt.h>
21
22#include <asm/cio.h>
23#include <asm/delay.h>
24#include <asm/irq.h>
25
26#include "airq.h"
27#include "cio.h"
28#include "css.h"
29#include "chsc.h"
30#include "ioasm.h"
31#include "blacklist.h"
32#include "cio_debug.h"
33
34debug_info_t *cio_debug_msg_id;
35debug_info_t *cio_debug_trace_id;
36debug_info_t *cio_debug_crw_id;
37
38int cio_show_msg;
39
40static int __init
41cio_setup (char *parm)
42{
43 if (!strcmp (parm, "yes"))
44 cio_show_msg = 1;
45 else if (!strcmp (parm, "no"))
46 cio_show_msg = 0;
47 else
48 printk (KERN_ERR "cio_setup : invalid cio_msg parameter '%s'",
49 parm);
50 return 1;
51}
52
53__setup ("cio_msg=", cio_setup);
54
55/*
56 * Function: cio_debug_init
57 * Initializes three debug logs (under /proc/s390dbf) for common I/O:
58 * - cio_msg logs the messages which are printk'ed when CONFIG_DEBUG_IO is on
59 * - cio_trace logs the calling of different functions
60 * - cio_crw logs the messages which are printk'ed when CONFIG_DEBUG_CRW is on
61 * debug levels depend on CONFIG_DEBUG_IO resp. CONFIG_DEBUG_CRW
62 */
63static int __init
64cio_debug_init (void)
65{
Michael Holzheu66a464d2005-06-25 14:55:33 -070066 cio_debug_msg_id = debug_register ("cio_msg", 16, 4, 16*sizeof (long));
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 if (!cio_debug_msg_id)
68 goto out_unregister;
69 debug_register_view (cio_debug_msg_id, &debug_sprintf_view);
70 debug_set_level (cio_debug_msg_id, 2);
Michael Holzheu66a464d2005-06-25 14:55:33 -070071 cio_debug_trace_id = debug_register ("cio_trace", 16, 4, 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 if (!cio_debug_trace_id)
73 goto out_unregister;
74 debug_register_view (cio_debug_trace_id, &debug_hex_ascii_view);
75 debug_set_level (cio_debug_trace_id, 2);
Michael Holzheu66a464d2005-06-25 14:55:33 -070076 cio_debug_crw_id = debug_register ("cio_crw", 4, 4, 16*sizeof (long));
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 if (!cio_debug_crw_id)
78 goto out_unregister;
79 debug_register_view (cio_debug_crw_id, &debug_sprintf_view);
80 debug_set_level (cio_debug_crw_id, 2);
81 pr_debug("debugging initialized\n");
82 return 0;
83
84out_unregister:
85 if (cio_debug_msg_id)
86 debug_unregister (cio_debug_msg_id);
87 if (cio_debug_trace_id)
88 debug_unregister (cio_debug_trace_id);
89 if (cio_debug_crw_id)
90 debug_unregister (cio_debug_crw_id);
91 pr_debug("could not initialize debugging\n");
92 return -1;
93}
94
95arch_initcall (cio_debug_init);
96
97int
98cio_set_options (struct subchannel *sch, int flags)
99{
100 sch->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
101 sch->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
102 sch->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
103 return 0;
104}
105
106/* FIXME: who wants to use this? */
107int
108cio_get_options (struct subchannel *sch)
109{
110 int flags;
111
112 flags = 0;
113 if (sch->options.suspend)
114 flags |= DOIO_ALLOW_SUSPEND;
115 if (sch->options.prefetch)
116 flags |= DOIO_DENY_PREFETCH;
117 if (sch->options.inter)
118 flags |= DOIO_SUPPRESS_INTER;
119 return flags;
120}
121
122/*
123 * Use tpi to get a pending interrupt, call the interrupt handler and
124 * return a pointer to the subchannel structure.
125 */
126static inline int
127cio_tpi(void)
128{
129 struct tpi_info *tpi_info;
130 struct subchannel *sch;
131 struct irb *irb;
132
133 tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
134 if (tpi (NULL) != 1)
135 return 0;
136 irb = (struct irb *) __LC_IRB;
137 /* Store interrupt response block to lowcore. */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800138 if (tsch (tpi_info->schid, irb) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 /* Not status pending or not operational. */
140 return 1;
141 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
142 if (!sch)
143 return 1;
144 local_bh_disable();
145 irq_enter ();
146 spin_lock(&sch->lock);
147 memcpy (&sch->schib.scsw, &irb->scsw, sizeof (struct scsw));
148 if (sch->driver && sch->driver->irq)
149 sch->driver->irq(&sch->dev);
150 spin_unlock(&sch->lock);
151 irq_exit ();
152 __local_bh_enable();
153 return 1;
154}
155
156static inline int
157cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
158{
159 char dbf_text[15];
160
161 if (lpm != 0)
162 sch->lpm &= ~lpm;
163 else
164 sch->lpm = 0;
165
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800166 stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
168 CIO_MSG_EVENT(0, "cio_start: 'not oper' status for "
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800169 "subchannel 0.%x.%04x!\n", sch->schid.ssid,
170 sch->schid.sch_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 sprintf(dbf_text, "no%s", sch->dev.bus_id);
172 CIO_TRACE_EVENT(0, dbf_text);
173 CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
174
175 return (sch->lpm ? -EACCES : -ENODEV);
176}
177
178int
179cio_start_key (struct subchannel *sch, /* subchannel structure */
180 struct ccw1 * cpa, /* logical channel prog addr */
181 __u8 lpm, /* logical path mask */
182 __u8 key) /* storage key */
183{
184 char dbf_txt[15];
185 int ccode;
186
187 CIO_TRACE_EVENT (4, "stIO");
188 CIO_TRACE_EVENT (4, sch->dev.bus_id);
189
190 /* sch is always under 2G. */
191 sch->orb.intparm = (__u32)(unsigned long)sch;
192 sch->orb.fmt = 1;
193
194 sch->orb.pfch = sch->options.prefetch == 0;
195 sch->orb.spnd = sch->options.suspend;
196 sch->orb.ssic = sch->options.suspend && sch->options.inter;
197 sch->orb.lpm = (lpm != 0) ? (lpm & sch->opm) : sch->lpm;
198#ifdef CONFIG_ARCH_S390X
199 /*
200 * for 64 bit we always support 64 bit IDAWs with 4k page size only
201 */
202 sch->orb.c64 = 1;
203 sch->orb.i2k = 0;
204#endif
205 sch->orb.key = key >> 4;
206 /* issue "Start Subchannel" */
207 sch->orb.cpa = (__u32) __pa (cpa);
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800208 ccode = ssch (sch->schid, &sch->orb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210 /* process condition code */
211 sprintf (dbf_txt, "ccode:%d", ccode);
212 CIO_TRACE_EVENT (4, dbf_txt);
213
214 switch (ccode) {
215 case 0:
216 /*
217 * initialize device status information
218 */
219 sch->schib.scsw.actl |= SCSW_ACTL_START_PEND;
220 return 0;
221 case 1: /* status pending */
222 case 2: /* busy */
223 return -EBUSY;
224 default: /* device/path not operational */
225 return cio_start_handle_notoper(sch, lpm);
226 }
227}
228
229int
230cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
231{
Peter Oberparleiter0b642ed2005-05-01 08:58:58 -0700232 return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233}
234
235/*
236 * resume suspended I/O operation
237 */
238int
239cio_resume (struct subchannel *sch)
240{
241 char dbf_txt[15];
242 int ccode;
243
244 CIO_TRACE_EVENT (4, "resIO");
245 CIO_TRACE_EVENT (4, sch->dev.bus_id);
246
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800247 ccode = rsch (sch->schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
249 sprintf (dbf_txt, "ccode:%d", ccode);
250 CIO_TRACE_EVENT (4, dbf_txt);
251
252 switch (ccode) {
253 case 0:
254 sch->schib.scsw.actl |= SCSW_ACTL_RESUME_PEND;
255 return 0;
256 case 1:
257 return -EBUSY;
258 case 2:
259 return -EINVAL;
260 default:
261 /*
262 * useless to wait for request completion
263 * as device is no longer operational !
264 */
265 return -ENODEV;
266 }
267}
268
269/*
270 * halt I/O operation
271 */
272int
273cio_halt(struct subchannel *sch)
274{
275 char dbf_txt[15];
276 int ccode;
277
278 if (!sch)
279 return -ENODEV;
280
281 CIO_TRACE_EVENT (2, "haltIO");
282 CIO_TRACE_EVENT (2, sch->dev.bus_id);
283
284 /*
285 * Issue "Halt subchannel" and process condition code
286 */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800287 ccode = hsch (sch->schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
289 sprintf (dbf_txt, "ccode:%d", ccode);
290 CIO_TRACE_EVENT (2, dbf_txt);
291
292 switch (ccode) {
293 case 0:
294 sch->schib.scsw.actl |= SCSW_ACTL_HALT_PEND;
295 return 0;
296 case 1: /* status pending */
297 case 2: /* busy */
298 return -EBUSY;
299 default: /* device not operational */
300 return -ENODEV;
301 }
302}
303
304/*
305 * Clear I/O operation
306 */
307int
308cio_clear(struct subchannel *sch)
309{
310 char dbf_txt[15];
311 int ccode;
312
313 if (!sch)
314 return -ENODEV;
315
316 CIO_TRACE_EVENT (2, "clearIO");
317 CIO_TRACE_EVENT (2, sch->dev.bus_id);
318
319 /*
320 * Issue "Clear subchannel" and process condition code
321 */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800322 ccode = csch (sch->schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
324 sprintf (dbf_txt, "ccode:%d", ccode);
325 CIO_TRACE_EVENT (2, dbf_txt);
326
327 switch (ccode) {
328 case 0:
329 sch->schib.scsw.actl |= SCSW_ACTL_CLEAR_PEND;
330 return 0;
331 default: /* device not operational */
332 return -ENODEV;
333 }
334}
335
336/*
337 * Function: cio_cancel
338 * Issues a "Cancel Subchannel" on the specified subchannel
339 * Note: We don't need any fancy intparms and flags here
340 * since xsch is executed synchronously.
341 * Only for common I/O internal use as for now.
342 */
343int
344cio_cancel (struct subchannel *sch)
345{
346 char dbf_txt[15];
347 int ccode;
348
349 if (!sch)
350 return -ENODEV;
351
352 CIO_TRACE_EVENT (2, "cancelIO");
353 CIO_TRACE_EVENT (2, sch->dev.bus_id);
354
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800355 ccode = xsch (sch->schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
357 sprintf (dbf_txt, "ccode:%d", ccode);
358 CIO_TRACE_EVENT (2, dbf_txt);
359
360 switch (ccode) {
361 case 0: /* success */
362 /* Update information in scsw. */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800363 stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 return 0;
365 case 1: /* status pending */
366 return -EBUSY;
367 case 2: /* not applicable */
368 return -EINVAL;
369 default: /* not oper */
370 return -ENODEV;
371 }
372}
373
374/*
375 * Function: cio_modify
376 * Issues a "Modify Subchannel" on the specified subchannel
377 */
378int
379cio_modify (struct subchannel *sch)
380{
381 int ccode, retry, ret;
382
383 ret = 0;
384 for (retry = 0; retry < 5; retry++) {
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800385 ccode = msch_err (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 if (ccode < 0) /* -EIO if msch gets a program check. */
387 return ccode;
388 switch (ccode) {
389 case 0: /* successfull */
390 return 0;
391 case 1: /* status pending */
392 return -EBUSY;
393 case 2: /* busy */
394 udelay (100); /* allow for recovery */
395 ret = -EBUSY;
396 break;
397 case 3: /* not operational */
398 return -ENODEV;
399 }
400 }
401 return ret;
402}
403
404/*
405 * Enable subchannel.
406 */
407int
408cio_enable_subchannel (struct subchannel *sch, unsigned int isc)
409{
410 char dbf_txt[15];
411 int ccode;
412 int retry;
413 int ret;
414
415 CIO_TRACE_EVENT (2, "ensch");
416 CIO_TRACE_EVENT (2, sch->dev.bus_id);
417
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800418 ccode = stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 if (ccode)
420 return -ENODEV;
421
422 for (retry = 5, ret = 0; retry > 0; retry--) {
423 sch->schib.pmcw.ena = 1;
424 sch->schib.pmcw.isc = isc;
425 sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
426 ret = cio_modify(sch);
427 if (ret == -ENODEV)
428 break;
429 if (ret == -EIO)
430 /*
431 * Got a program check in cio_modify. Try without
432 * the concurrent sense bit the next time.
433 */
434 sch->schib.pmcw.csense = 0;
435 if (ret == 0) {
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800436 stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 if (sch->schib.pmcw.ena)
438 break;
439 }
440 if (ret == -EBUSY) {
441 struct irb irb;
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800442 if (tsch(sch->schid, &irb) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 break;
444 }
445 }
446 sprintf (dbf_txt, "ret:%d", ret);
447 CIO_TRACE_EVENT (2, dbf_txt);
448 return ret;
449}
450
451/*
452 * Disable subchannel.
453 */
454int
455cio_disable_subchannel (struct subchannel *sch)
456{
457 char dbf_txt[15];
458 int ccode;
459 int retry;
460 int ret;
461
462 CIO_TRACE_EVENT (2, "dissch");
463 CIO_TRACE_EVENT (2, sch->dev.bus_id);
464
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800465 ccode = stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 if (ccode == 3) /* Not operational. */
467 return -ENODEV;
468
469 if (sch->schib.scsw.actl != 0)
470 /*
471 * the disable function must not be called while there are
472 * requests pending for completion !
473 */
474 return -EBUSY;
475
476 for (retry = 5, ret = 0; retry > 0; retry--) {
477 sch->schib.pmcw.ena = 0;
478 ret = cio_modify(sch);
479 if (ret == -ENODEV)
480 break;
481 if (ret == -EBUSY)
482 /*
483 * The subchannel is busy or status pending.
484 * We'll disable when the next interrupt was delivered
485 * via the state machine.
486 */
487 break;
488 if (ret == 0) {
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800489 stsch (sch->schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 if (!sch->schib.pmcw.ena)
491 break;
492 }
493 }
494 sprintf (dbf_txt, "ret:%d", ret);
495 CIO_TRACE_EVENT (2, dbf_txt);
496 return ret;
497}
498
499/*
500 * cio_validate_subchannel()
501 *
502 * Find out subchannel type and initialize struct subchannel.
503 * Return codes:
504 * SUBCHANNEL_TYPE_IO for a normal io subchannel
505 * SUBCHANNEL_TYPE_CHSC for a chsc subchannel
506 * SUBCHANNEL_TYPE_MESSAGE for a messaging subchannel
507 * SUBCHANNEL_TYPE_ADM for a adm(?) subchannel
508 * -ENXIO for non-defined subchannels
509 * -ENODEV for subchannels with invalid device number or blacklisted devices
510 */
511int
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800512cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513{
514 char dbf_txt[15];
515 int ccode;
516
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800517 sprintf (dbf_txt, "valsch%x", schid.sch_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 CIO_TRACE_EVENT (4, dbf_txt);
519
520 /* Nuke all fields. */
521 memset(sch, 0, sizeof(struct subchannel));
522
523 spin_lock_init(&sch->lock);
524
525 /* Set a name for the subchannel */
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800526 snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x", schid.ssid,
527 schid.sch_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528
529 /*
530 * The first subchannel that is not-operational (ccode==3)
531 * indicates that there aren't any more devices available.
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800532 * If stsch gets an exception, it means the current subchannel set
533 * is not valid.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 */
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800535 ccode = stsch_err (schid, &sch->schib);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 if (ccode)
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800537 return (ccode == 3) ? -ENXIO : ccode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800539 sch->schid = schid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 /* Copy subchannel type from path management control word. */
541 sch->st = sch->schib.pmcw.st;
542
543 /*
544 * ... just being curious we check for non I/O subchannels
545 */
546 if (sch->st != 0) {
547 CIO_DEBUG(KERN_INFO, 0,
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800548 "Subchannel 0.%x.%04x reports "
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 "non-I/O subchannel type %04X\n",
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800550 sch->schid.ssid, sch->schid.sch_no, sch->st);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 /* We stop here for non-io subchannels. */
552 return sch->st;
553 }
554
555 /* Initialization for io subchannels. */
556 if (!sch->schib.pmcw.dnv)
557 /* io subchannel but device number is invalid. */
558 return -ENODEV;
559
560 /* Devno is valid. */
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800561 if (is_blacklisted (sch->schid.ssid, sch->schib.pmcw.dev)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 /*
563 * This device must not be known to Linux. So we simply
564 * say that there is no device and return ENODEV.
565 */
566 CIO_MSG_EVENT(0, "Blacklisted device detected "
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800567 "at devno %04X, subchannel set %x\n",
568 sch->schib.pmcw.dev, sch->schid.ssid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 return -ENODEV;
570 }
571 sch->opm = 0xff;
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800572 if (!cio_is_console(sch->schid))
573 chsc_validate_chpids(sch);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 sch->lpm = sch->schib.pmcw.pim &
575 sch->schib.pmcw.pam &
576 sch->schib.pmcw.pom &
577 sch->opm;
578
579 CIO_DEBUG(KERN_INFO, 0,
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800580 "Detected device %04x on subchannel 0.%x.%04X"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 " - PIM = %02X, PAM = %02X, POM = %02X\n",
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800582 sch->schib.pmcw.dev, sch->schid.ssid,
583 sch->schid.sch_no, sch->schib.pmcw.pim,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 sch->schib.pmcw.pam, sch->schib.pmcw.pom);
585
586 /*
587 * We now have to initially ...
588 * ... set "interruption subclass"
589 * ... enable "concurrent sense"
590 * ... enable "multipath mode" if more than one
591 * CHPID is available. This is done regardless
592 * whether multiple paths are available for us.
593 */
594 sch->schib.pmcw.isc = 3; /* could be smth. else */
595 sch->schib.pmcw.csense = 1; /* concurrent sense */
596 sch->schib.pmcw.ena = 0;
597 if ((sch->lpm & (sch->lpm - 1)) != 0)
598 sch->schib.pmcw.mp = 1; /* multipath mode */
599 return 0;
600}
601
602/*
603 * do_IRQ() handles all normal I/O device IRQ's (the special
604 * SMP cross-CPU interrupts have their own specific
605 * handlers).
606 *
607 */
608void
609do_IRQ (struct pt_regs *regs)
610{
611 struct tpi_info *tpi_info;
612 struct subchannel *sch;
613 struct irb *irb;
614
615 irq_enter ();
616 asm volatile ("mc 0,0");
617 if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
618 /**
619 * Make sure that the i/o interrupt did not "overtake"
620 * the last HZ timer interrupt.
621 */
622 account_ticks(regs);
623 /*
624 * Get interrupt information from lowcore
625 */
626 tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
627 irb = (struct irb *) __LC_IRB;
628 do {
629 kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
630 /*
631 * Non I/O-subchannel thin interrupts are processed differently
632 */
633 if (tpi_info->adapter_IO == 1 &&
634 tpi_info->int_type == IO_INTERRUPT_TYPE) {
635 do_adapter_IO();
636 continue;
637 }
638 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
639 if (sch)
640 spin_lock(&sch->lock);
641 /* Store interrupt response block to lowcore. */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800642 if (tsch (tpi_info->schid, irb) == 0 && sch) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 /* Keep subchannel information word up to date. */
644 memcpy (&sch->schib.scsw, &irb->scsw,
645 sizeof (irb->scsw));
646 /* Call interrupt handler if there is one. */
647 if (sch->driver && sch->driver->irq)
648 sch->driver->irq(&sch->dev);
649 }
650 if (sch)
651 spin_unlock(&sch->lock);
652 /*
653 * Are more interrupts pending?
654 * If so, the tpi instruction will update the lowcore
655 * to hold the info for the next interrupt.
656 * We don't do this for VM because a tpi drops the cpu
657 * out of the sie which costs more cycles than it saves.
658 */
659 } while (!MACHINE_IS_VM && tpi (NULL) != 0);
660 irq_exit ();
661}
662
663#ifdef CONFIG_CCW_CONSOLE
664static struct subchannel console_subchannel;
665static int console_subchannel_in_use;
666
667/*
668 * busy wait for the next interrupt on the console
669 */
670void
671wait_cons_dev (void)
672{
673 unsigned long cr6 __attribute__ ((aligned (8)));
674 unsigned long save_cr6 __attribute__ ((aligned (8)));
675
676 /*
677 * before entering the spinlock we may already have
678 * processed the interrupt on a different CPU...
679 */
680 if (!console_subchannel_in_use)
681 return;
682
683 /* disable all but isc 7 (console device) */
684 __ctl_store (save_cr6, 6, 6);
685 cr6 = 0x01000000;
686 __ctl_load (cr6, 6, 6);
687
688 do {
689 spin_unlock(&console_subchannel.lock);
690 if (!cio_tpi())
691 cpu_relax();
692 spin_lock(&console_subchannel.lock);
693 } while (console_subchannel.schib.scsw.actl != 0);
694 /*
695 * restore previous isc value
696 */
697 __ctl_load (save_cr6, 6, 6);
698}
699
700static int
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800701cio_test_for_console(struct subchannel_id schid, void *data)
702{
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800703 if (stsch_err(schid, &console_subchannel.schib) != 0)
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800704 return -ENXIO;
705 if (console_subchannel.schib.pmcw.dnv &&
706 console_subchannel.schib.pmcw.dev ==
707 console_devno) {
708 console_irq = schid.sch_no;
709 return 1; /* found */
710 }
711 return 0;
712}
713
714
715static int
716cio_get_console_sch_no(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800718 struct subchannel_id schid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800720 init_subchannel_id(&schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 if (console_irq != -1) {
722 /* VM provided us with the irq number of the console. */
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800723 schid.sch_no = console_irq;
724 if (stsch(schid, &console_subchannel.schib) != 0 ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 !console_subchannel.schib.pmcw.dnv)
726 return -1;
727 console_devno = console_subchannel.schib.pmcw.dev;
728 } else if (console_devno != -1) {
729 /* At least the console device number is known. */
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800730 for_each_subchannel(cio_test_for_console, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 if (console_irq == -1)
732 return -1;
733 } else {
734 /* unlike in 2.4, we cannot autoprobe here, since
735 * the channel subsystem is not fully initialized.
736 * With some luck, the HWC console can take over */
737 printk(KERN_WARNING "No ccw console found!\n");
738 return -1;
739 }
740 return console_irq;
741}
742
743struct subchannel *
744cio_probe_console(void)
745{
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800746 int sch_no, ret;
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800747 struct subchannel_id schid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748
749 if (xchg(&console_subchannel_in_use, 1) != 0)
750 return ERR_PTR(-EBUSY);
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800751 sch_no = cio_get_console_sch_no();
752 if (sch_no == -1) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 console_subchannel_in_use = 0;
754 return ERR_PTR(-ENODEV);
755 }
756 memset(&console_subchannel, 0, sizeof(struct subchannel));
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800757 init_subchannel_id(&schid);
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800758 schid.sch_no = sch_no;
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800759 ret = cio_validate_subchannel(&console_subchannel, schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760 if (ret) {
761 console_subchannel_in_use = 0;
762 return ERR_PTR(-ENODEV);
763 }
764
765 /*
766 * enable console I/O-interrupt subclass 7
767 */
768 ctl_set_bit(6, 24);
769 console_subchannel.schib.pmcw.isc = 7;
770 console_subchannel.schib.pmcw.intparm =
771 (__u32)(unsigned long)&console_subchannel;
772 ret = cio_modify(&console_subchannel);
773 if (ret) {
774 console_subchannel_in_use = 0;
775 return ERR_PTR(ret);
776 }
777 return &console_subchannel;
778}
779
780void
781cio_release_console(void)
782{
783 console_subchannel.schib.pmcw.intparm = 0;
784 cio_modify(&console_subchannel);
785 ctl_clear_bit(6, 24);
786 console_subchannel_in_use = 0;
787}
788
789/* Bah... hack to catch console special sausages. */
790int
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800791cio_is_console(struct subchannel_id schid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792{
793 if (!console_subchannel_in_use)
794 return 0;
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800795 return schid_equal(&schid, &console_subchannel.schid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796}
797
798struct subchannel *
799cio_get_console_subchannel(void)
800{
801 if (!console_subchannel_in_use)
802 return 0;
803 return &console_subchannel;
804}
805
806#endif
807static inline int
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800808__disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809{
810 int retry, cc;
811
812 cc = 0;
813 for (retry=0;retry<3;retry++) {
814 schib->pmcw.ena = 0;
815 cc = msch(schid, schib);
816 if (cc)
817 return (cc==3?-ENODEV:-EBUSY);
818 stsch(schid, schib);
819 if (!schib->pmcw.ena)
820 return 0;
821 }
822 return -EBUSY; /* uhm... */
823}
824
825static inline int
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800826__clear_subchannel_easy(struct subchannel_id schid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827{
828 int retry;
829
830 if (csch(schid))
831 return -ENODEV;
832 for (retry=0;retry<20;retry++) {
833 struct tpi_info ti;
834
835 if (tpi(&ti)) {
Cornelia Hucka8237fc2006-01-06 00:19:21 -0800836 tsch(ti.schid, (struct irb *)__LC_IRB);
837 if (schid_equal(&ti.schid, &schid))
Cornelia Huck4c24da72005-09-03 15:58:01 -0700838 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 }
840 udelay(100);
841 }
842 return -EBUSY;
843}
844
845extern void do_reipl(unsigned long devno);
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800846static int
847__shutdown_subchannel_easy(struct subchannel_id schid, void *data)
848{
849 struct schib schib;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850
Cornelia Huckfb6958a2006-01-06 00:19:25 -0800851 if (stsch_err(schid, &schib))
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800852 return -ENXIO;
853 if (!schib.pmcw.ena)
854 return 0;
855 switch(__disable_subchannel_easy(schid, &schib)) {
856 case 0:
857 case -ENODEV:
858 break;
859 default: /* -EBUSY */
860 if (__clear_subchannel_easy(schid))
861 break; /* give up... */
862 stsch(schid, &schib);
863 __disable_subchannel_easy(schid, &schib);
864 }
865 return 0;
866}
867
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868void
869clear_all_subchannels(void)
870{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 local_irq_disable();
Cornelia Huckf97a56f2006-01-06 00:19:22 -0800872 for_each_subchannel(__shutdown_subchannel_easy, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873}
874
875/* Make sure all subchannels are quiet before we re-ipl an lpar. */
876void
877reipl(unsigned long devno)
878{
879 clear_all_subchannels();
880 do_reipl(devno);
881}