i2c-eg20t: change timeout value 50msec to 1000msec
[zen-stable.git] / drivers / s390 / cio / cio.c
blobdc67c397449e529f7cb377f776df6784d72944c1
1 /*
2 * drivers/s390/cio/cio.c
3 * S/390 common I/O routines -- low level i/o calls
5 * Copyright IBM Corp. 1999,2008
6 * Author(s): Ingo Adlung (adlung@de.ibm.com)
7 * Cornelia Huck (cornelia.huck@de.ibm.com)
8 * Arnd Bergmann (arndb@de.ibm.com)
9 * Martin Schwidefsky (schwidefsky@de.ibm.com)
12 #define KMSG_COMPONENT "cio"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15 #include <linux/ftrace.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/device.h>
20 #include <linux/kernel_stat.h>
21 #include <linux/interrupt.h>
22 #include <asm/cio.h>
23 #include <asm/delay.h>
24 #include <asm/irq.h>
25 #include <asm/irq_regs.h>
26 #include <asm/setup.h>
27 #include <asm/reset.h>
28 #include <asm/ipl.h>
29 #include <asm/chpid.h>
30 #include <asm/airq.h>
31 #include <asm/isc.h>
32 #include <asm/cputime.h>
33 #include <asm/fcx.h>
34 #include <asm/nmi.h>
35 #include <asm/crw.h>
36 #include "cio.h"
37 #include "css.h"
38 #include "chsc.h"
39 #include "ioasm.h"
40 #include "io_sch.h"
41 #include "blacklist.h"
42 #include "cio_debug.h"
43 #include "chp.h"
45 debug_info_t *cio_debug_msg_id;
46 debug_info_t *cio_debug_trace_id;
47 debug_info_t *cio_debug_crw_id;
50 * Function: cio_debug_init
51 * Initializes three debug logs for common I/O:
52 * - cio_msg logs generic cio messages
53 * - cio_trace logs the calling of different functions
54 * - cio_crw logs machine check related cio messages
56 static int __init cio_debug_init(void)
58 cio_debug_msg_id = debug_register("cio_msg", 16, 1, 16 * sizeof(long));
59 if (!cio_debug_msg_id)
60 goto out_unregister;
61 debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
62 debug_set_level(cio_debug_msg_id, 2);
63 cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
64 if (!cio_debug_trace_id)
65 goto out_unregister;
66 debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
67 debug_set_level(cio_debug_trace_id, 2);
68 cio_debug_crw_id = debug_register("cio_crw", 16, 1, 16 * sizeof(long));
69 if (!cio_debug_crw_id)
70 goto out_unregister;
71 debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
72 debug_set_level(cio_debug_crw_id, 4);
73 return 0;
75 out_unregister:
76 if (cio_debug_msg_id)
77 debug_unregister(cio_debug_msg_id);
78 if (cio_debug_trace_id)
79 debug_unregister(cio_debug_trace_id);
80 if (cio_debug_crw_id)
81 debug_unregister(cio_debug_crw_id);
82 return -1;
85 arch_initcall (cio_debug_init);
87 int cio_set_options(struct subchannel *sch, int flags)
89 struct io_subchannel_private *priv = to_io_private(sch);
91 priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
92 priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
93 priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
94 return 0;
97 static int
98 cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
100 char dbf_text[15];
102 if (lpm != 0)
103 sch->lpm &= ~lpm;
104 else
105 sch->lpm = 0;
107 CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
108 "subchannel 0.%x.%04x!\n", sch->schid.ssid,
109 sch->schid.sch_no);
111 if (cio_update_schib(sch))
112 return -ENODEV;
114 sprintf(dbf_text, "no%s", dev_name(&sch->dev));
115 CIO_TRACE_EVENT(0, dbf_text);
116 CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
118 return (sch->lpm ? -EACCES : -ENODEV);
122 cio_start_key (struct subchannel *sch, /* subchannel structure */
123 struct ccw1 * cpa, /* logical channel prog addr */
124 __u8 lpm, /* logical path mask */
125 __u8 key) /* storage key */
127 struct io_subchannel_private *priv = to_io_private(sch);
128 union orb *orb = &priv->orb;
129 int ccode;
131 CIO_TRACE_EVENT(5, "stIO");
132 CIO_TRACE_EVENT(5, dev_name(&sch->dev));
134 memset(orb, 0, sizeof(union orb));
135 /* sch is always under 2G. */
136 orb->cmd.intparm = (u32)(addr_t)sch;
137 orb->cmd.fmt = 1;
139 orb->cmd.pfch = priv->options.prefetch == 0;
140 orb->cmd.spnd = priv->options.suspend;
141 orb->cmd.ssic = priv->options.suspend && priv->options.inter;
142 orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm;
143 #ifdef CONFIG_64BIT
145 * for 64 bit we always support 64 bit IDAWs with 4k page size only
147 orb->cmd.c64 = 1;
148 orb->cmd.i2k = 0;
149 #endif
150 orb->cmd.key = key >> 4;
151 /* issue "Start Subchannel" */
152 orb->cmd.cpa = (__u32) __pa(cpa);
153 ccode = ssch(sch->schid, orb);
155 /* process condition code */
156 CIO_HEX_EVENT(5, &ccode, sizeof(ccode));
158 switch (ccode) {
159 case 0:
161 * initialize device status information
163 sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND;
164 return 0;
165 case 1: /* status pending */
166 case 2: /* busy */
167 return -EBUSY;
168 case 3: /* device/path not operational */
169 return cio_start_handle_notoper(sch, lpm);
170 default:
171 return ccode;
176 cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
178 return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
182 * resume suspended I/O operation
185 cio_resume (struct subchannel *sch)
187 int ccode;
189 CIO_TRACE_EVENT(4, "resIO");
190 CIO_TRACE_EVENT(4, dev_name(&sch->dev));
192 ccode = rsch (sch->schid);
194 CIO_HEX_EVENT(4, &ccode, sizeof(ccode));
196 switch (ccode) {
197 case 0:
198 sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND;
199 return 0;
200 case 1:
201 return -EBUSY;
202 case 2:
203 return -EINVAL;
204 default:
206 * useless to wait for request completion
207 * as device is no longer operational !
209 return -ENODEV;
214 * halt I/O operation
217 cio_halt(struct subchannel *sch)
219 int ccode;
221 if (!sch)
222 return -ENODEV;
224 CIO_TRACE_EVENT(2, "haltIO");
225 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
228 * Issue "Halt subchannel" and process condition code
230 ccode = hsch (sch->schid);
232 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
234 switch (ccode) {
235 case 0:
236 sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND;
237 return 0;
238 case 1: /* status pending */
239 case 2: /* busy */
240 return -EBUSY;
241 default: /* device not operational */
242 return -ENODEV;
247 * Clear I/O operation
250 cio_clear(struct subchannel *sch)
252 int ccode;
254 if (!sch)
255 return -ENODEV;
257 CIO_TRACE_EVENT(2, "clearIO");
258 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
261 * Issue "Clear subchannel" and process condition code
263 ccode = csch (sch->schid);
265 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
267 switch (ccode) {
268 case 0:
269 sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND;
270 return 0;
271 default: /* device not operational */
272 return -ENODEV;
277 * Function: cio_cancel
278 * Issues a "Cancel Subchannel" on the specified subchannel
279 * Note: We don't need any fancy intparms and flags here
280 * since xsch is executed synchronously.
281 * Only for common I/O internal use as for now.
284 cio_cancel (struct subchannel *sch)
286 int ccode;
288 if (!sch)
289 return -ENODEV;
291 CIO_TRACE_EVENT(2, "cancelIO");
292 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
294 ccode = xsch (sch->schid);
296 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
298 switch (ccode) {
299 case 0: /* success */
300 /* Update information in scsw. */
301 if (cio_update_schib(sch))
302 return -ENODEV;
303 return 0;
304 case 1: /* status pending */
305 return -EBUSY;
306 case 2: /* not applicable */
307 return -EINVAL;
308 default: /* not oper */
309 return -ENODEV;
314 static void cio_apply_config(struct subchannel *sch, struct schib *schib)
316 schib->pmcw.intparm = sch->config.intparm;
317 schib->pmcw.mbi = sch->config.mbi;
318 schib->pmcw.isc = sch->config.isc;
319 schib->pmcw.ena = sch->config.ena;
320 schib->pmcw.mme = sch->config.mme;
321 schib->pmcw.mp = sch->config.mp;
322 schib->pmcw.csense = sch->config.csense;
323 schib->pmcw.mbfc = sch->config.mbfc;
324 if (sch->config.mbfc)
325 schib->mba = sch->config.mba;
328 static int cio_check_config(struct subchannel *sch, struct schib *schib)
330 return (schib->pmcw.intparm == sch->config.intparm) &&
331 (schib->pmcw.mbi == sch->config.mbi) &&
332 (schib->pmcw.isc == sch->config.isc) &&
333 (schib->pmcw.ena == sch->config.ena) &&
334 (schib->pmcw.mme == sch->config.mme) &&
335 (schib->pmcw.mp == sch->config.mp) &&
336 (schib->pmcw.csense == sch->config.csense) &&
337 (schib->pmcw.mbfc == sch->config.mbfc) &&
338 (!sch->config.mbfc || (schib->mba == sch->config.mba));
342 * cio_commit_config - apply configuration to the subchannel
344 int cio_commit_config(struct subchannel *sch)
346 struct schib schib;
347 int ccode, retry, ret = 0;
349 if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib))
350 return -ENODEV;
352 for (retry = 0; retry < 5; retry++) {
353 /* copy desired changes to local schib */
354 cio_apply_config(sch, &schib);
355 ccode = msch_err(sch->schid, &schib);
356 if (ccode < 0) /* -EIO if msch gets a program check. */
357 return ccode;
358 switch (ccode) {
359 case 0: /* successful */
360 if (stsch_err(sch->schid, &schib) ||
361 !css_sch_is_valid(&schib))
362 return -ENODEV;
363 if (cio_check_config(sch, &schib)) {
364 /* commit changes from local schib */
365 memcpy(&sch->schib, &schib, sizeof(schib));
366 return 0;
368 ret = -EAGAIN;
369 break;
370 case 1: /* status pending */
371 return -EBUSY;
372 case 2: /* busy */
373 udelay(100); /* allow for recovery */
374 ret = -EBUSY;
375 break;
376 case 3: /* not operational */
377 return -ENODEV;
380 return ret;
384 * cio_update_schib - Perform stsch and update schib if subchannel is valid.
385 * @sch: subchannel on which to perform stsch
386 * Return zero on success, -ENODEV otherwise.
388 int cio_update_schib(struct subchannel *sch)
390 struct schib schib;
392 if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib))
393 return -ENODEV;
395 memcpy(&sch->schib, &schib, sizeof(schib));
396 return 0;
398 EXPORT_SYMBOL_GPL(cio_update_schib);
401 * cio_enable_subchannel - enable a subchannel.
402 * @sch: subchannel to be enabled
403 * @intparm: interruption parameter to set
405 int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
407 int retry;
408 int ret;
410 CIO_TRACE_EVENT(2, "ensch");
411 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
413 if (sch_is_pseudo_sch(sch))
414 return -EINVAL;
415 if (cio_update_schib(sch))
416 return -ENODEV;
418 sch->config.ena = 1;
419 sch->config.isc = sch->isc;
420 sch->config.intparm = intparm;
422 for (retry = 0; retry < 3; retry++) {
423 ret = cio_commit_config(sch);
424 if (ret == -EIO) {
426 * Got a program check in msch. Try without
427 * the concurrent sense bit the next time.
429 sch->config.csense = 0;
430 } else if (ret == -EBUSY) {
431 struct irb irb;
432 if (tsch(sch->schid, &irb) != 0)
433 break;
434 } else
435 break;
437 CIO_HEX_EVENT(2, &ret, sizeof(ret));
438 return ret;
440 EXPORT_SYMBOL_GPL(cio_enable_subchannel);
443 * cio_disable_subchannel - disable a subchannel.
444 * @sch: subchannel to disable
446 int cio_disable_subchannel(struct subchannel *sch)
448 int retry;
449 int ret;
451 CIO_TRACE_EVENT(2, "dissch");
452 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
454 if (sch_is_pseudo_sch(sch))
455 return 0;
456 if (cio_update_schib(sch))
457 return -ENODEV;
459 sch->config.ena = 0;
461 for (retry = 0; retry < 3; retry++) {
462 ret = cio_commit_config(sch);
463 if (ret == -EBUSY) {
464 struct irb irb;
465 if (tsch(sch->schid, &irb) != 0)
466 break;
467 } else
468 break;
470 CIO_HEX_EVENT(2, &ret, sizeof(ret));
471 return ret;
473 EXPORT_SYMBOL_GPL(cio_disable_subchannel);
475 int cio_create_sch_lock(struct subchannel *sch)
477 sch->lock = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
478 if (!sch->lock)
479 return -ENOMEM;
480 spin_lock_init(sch->lock);
481 return 0;
484 static int cio_check_devno_blacklisted(struct subchannel *sch)
486 if (is_blacklisted(sch->schid.ssid, sch->schib.pmcw.dev)) {
488 * This device must not be known to Linux. So we simply
489 * say that there is no device and return ENODEV.
491 CIO_MSG_EVENT(6, "Blacklisted device detected "
492 "at devno %04X, subchannel set %x\n",
493 sch->schib.pmcw.dev, sch->schid.ssid);
494 return -ENODEV;
496 return 0;
499 static int cio_validate_io_subchannel(struct subchannel *sch)
501 /* Initialization for io subchannels. */
502 if (!css_sch_is_valid(&sch->schib))
503 return -ENODEV;
505 /* Devno is valid. */
506 return cio_check_devno_blacklisted(sch);
509 static int cio_validate_msg_subchannel(struct subchannel *sch)
511 /* Initialization for message subchannels. */
512 if (!css_sch_is_valid(&sch->schib))
513 return -ENODEV;
515 /* Devno is valid. */
516 return cio_check_devno_blacklisted(sch);
520 * cio_validate_subchannel - basic validation of subchannel
521 * @sch: subchannel structure to be filled out
522 * @schid: subchannel id
524 * Find out subchannel type and initialize struct subchannel.
525 * Return codes:
526 * 0 on success
527 * -ENXIO for non-defined subchannels
528 * -ENODEV for invalid subchannels or blacklisted devices
529 * -EIO for subchannels in an invalid subchannel set
531 int cio_validate_subchannel(struct subchannel *sch, struct subchannel_id schid)
533 char dbf_txt[15];
534 int ccode;
535 int err;
537 sprintf(dbf_txt, "valsch%x", schid.sch_no);
538 CIO_TRACE_EVENT(4, dbf_txt);
540 /* Nuke all fields. */
541 memset(sch, 0, sizeof(struct subchannel));
543 sch->schid = schid;
544 if (cio_is_console(schid)) {
545 sch->lock = cio_get_console_lock();
546 } else {
547 err = cio_create_sch_lock(sch);
548 if (err)
549 goto out;
551 mutex_init(&sch->reg_mutex);
554 * The first subchannel that is not-operational (ccode==3)
555 * indicates that there aren't any more devices available.
556 * If stsch gets an exception, it means the current subchannel set
557 * is not valid.
559 ccode = stsch_err (schid, &sch->schib);
560 if (ccode) {
561 err = (ccode == 3) ? -ENXIO : ccode;
562 goto out;
564 /* Copy subchannel type from path management control word. */
565 sch->st = sch->schib.pmcw.st;
567 switch (sch->st) {
568 case SUBCHANNEL_TYPE_IO:
569 err = cio_validate_io_subchannel(sch);
570 break;
571 case SUBCHANNEL_TYPE_MSG:
572 err = cio_validate_msg_subchannel(sch);
573 break;
574 default:
575 err = 0;
577 if (err)
578 goto out;
580 CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n",
581 sch->schid.ssid, sch->schid.sch_no, sch->st);
582 return 0;
583 out:
584 if (!cio_is_console(schid))
585 kfree(sch->lock);
586 sch->lock = NULL;
587 return err;
591 * do_IRQ() handles all normal I/O device IRQ's (the special
592 * SMP cross-CPU interrupts have their own specific
593 * handlers).
596 void __irq_entry do_IRQ(struct pt_regs *regs)
598 struct tpi_info *tpi_info;
599 struct subchannel *sch;
600 struct irb *irb;
601 struct pt_regs *old_regs;
603 old_regs = set_irq_regs(regs);
604 s390_idle_check(regs, S390_lowcore.int_clock,
605 S390_lowcore.async_enter_timer);
606 irq_enter();
607 __this_cpu_write(s390_idle.nohz_delay, 1);
608 if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
609 /* Serve timer interrupts first. */
610 clock_comparator_work();
612 * Get interrupt information from lowcore
614 tpi_info = (struct tpi_info *)&S390_lowcore.subchannel_id;
615 irb = (struct irb *)&S390_lowcore.irb;
616 do {
617 kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
618 if (tpi_info->adapter_IO) {
619 do_adapter_IO(tpi_info->isc);
620 continue;
622 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
623 if (!sch) {
624 /* Clear pending interrupt condition. */
625 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
626 tsch(tpi_info->schid, irb);
627 continue;
629 spin_lock(sch->lock);
630 /* Store interrupt response block to lowcore. */
631 if (tsch(tpi_info->schid, irb) == 0) {
632 /* Keep subchannel information word up to date. */
633 memcpy (&sch->schib.scsw, &irb->scsw,
634 sizeof (irb->scsw));
635 /* Call interrupt handler if there is one. */
636 if (sch->driver && sch->driver->irq)
637 sch->driver->irq(sch);
638 else
639 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
640 } else
641 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
642 spin_unlock(sch->lock);
644 * Are more interrupts pending?
645 * If so, the tpi instruction will update the lowcore
646 * to hold the info for the next interrupt.
647 * We don't do this for VM because a tpi drops the cpu
648 * out of the sie which costs more cycles than it saves.
650 } while (MACHINE_IS_LPAR && tpi(NULL) != 0);
651 irq_exit();
652 set_irq_regs(old_regs);
655 #ifdef CONFIG_CCW_CONSOLE
656 static struct subchannel console_subchannel;
657 static struct io_subchannel_private console_priv;
658 static int console_subchannel_in_use;
661 * Use cio_tpi to get a pending interrupt and call the interrupt handler.
662 * Return non-zero if an interrupt was processed, zero otherwise.
664 static int cio_tpi(void)
666 struct tpi_info *tpi_info;
667 struct subchannel *sch;
668 struct irb *irb;
669 int irq_context;
671 tpi_info = (struct tpi_info *)&S390_lowcore.subchannel_id;
672 if (tpi(NULL) != 1)
673 return 0;
674 kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
675 if (tpi_info->adapter_IO) {
676 do_adapter_IO(tpi_info->isc);
677 return 1;
679 irb = (struct irb *)&S390_lowcore.irb;
680 /* Store interrupt response block to lowcore. */
681 if (tsch(tpi_info->schid, irb) != 0) {
682 /* Not status pending or not operational. */
683 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
684 return 1;
686 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
687 if (!sch) {
688 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
689 return 1;
691 irq_context = in_interrupt();
692 if (!irq_context)
693 local_bh_disable();
694 irq_enter();
695 spin_lock(sch->lock);
696 memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
697 if (sch->driver && sch->driver->irq)
698 sch->driver->irq(sch);
699 else
700 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
701 spin_unlock(sch->lock);
702 irq_exit();
703 if (!irq_context)
704 _local_bh_enable();
705 return 1;
708 void *cio_get_console_priv(void)
710 return &console_priv;
714 * busy wait for the next interrupt on the console
716 void wait_cons_dev(void)
717 __releases(console_subchannel.lock)
718 __acquires(console_subchannel.lock)
720 unsigned long cr6 __attribute__ ((aligned (8)));
721 unsigned long save_cr6 __attribute__ ((aligned (8)));
724 * before entering the spinlock we may already have
725 * processed the interrupt on a different CPU...
727 if (!console_subchannel_in_use)
728 return;
730 /* disable all but the console isc */
731 __ctl_store (save_cr6, 6, 6);
732 cr6 = 1UL << (31 - CONSOLE_ISC);
733 __ctl_load (cr6, 6, 6);
735 do {
736 spin_unlock(console_subchannel.lock);
737 if (!cio_tpi())
738 cpu_relax();
739 spin_lock(console_subchannel.lock);
740 } while (console_subchannel.schib.scsw.cmd.actl != 0);
742 * restore previous isc value
744 __ctl_load (save_cr6, 6, 6);
747 static int
748 cio_test_for_console(struct subchannel_id schid, void *data)
750 if (stsch_err(schid, &console_subchannel.schib) != 0)
751 return -ENXIO;
752 if ((console_subchannel.schib.pmcw.st == SUBCHANNEL_TYPE_IO) &&
753 console_subchannel.schib.pmcw.dnv &&
754 (console_subchannel.schib.pmcw.dev == console_devno)) {
755 console_irq = schid.sch_no;
756 return 1; /* found */
758 return 0;
762 static int
763 cio_get_console_sch_no(void)
765 struct subchannel_id schid;
767 init_subchannel_id(&schid);
768 if (console_irq != -1) {
769 /* VM provided us with the irq number of the console. */
770 schid.sch_no = console_irq;
771 if (stsch_err(schid, &console_subchannel.schib) != 0 ||
772 (console_subchannel.schib.pmcw.st != SUBCHANNEL_TYPE_IO) ||
773 !console_subchannel.schib.pmcw.dnv)
774 return -1;
775 console_devno = console_subchannel.schib.pmcw.dev;
776 } else if (console_devno != -1) {
777 /* At least the console device number is known. */
778 for_each_subchannel(cio_test_for_console, NULL);
779 if (console_irq == -1)
780 return -1;
781 } else {
782 /* unlike in 2.4, we cannot autoprobe here, since
783 * the channel subsystem is not fully initialized.
784 * With some luck, the HWC console can take over */
785 return -1;
787 return console_irq;
790 struct subchannel *
791 cio_probe_console(void)
793 int sch_no, ret;
794 struct subchannel_id schid;
796 if (xchg(&console_subchannel_in_use, 1) != 0)
797 return ERR_PTR(-EBUSY);
798 sch_no = cio_get_console_sch_no();
799 if (sch_no == -1) {
800 console_subchannel_in_use = 0;
801 pr_warning("No CCW console was found\n");
802 return ERR_PTR(-ENODEV);
804 memset(&console_subchannel, 0, sizeof(struct subchannel));
805 init_subchannel_id(&schid);
806 schid.sch_no = sch_no;
807 ret = cio_validate_subchannel(&console_subchannel, schid);
808 if (ret) {
809 console_subchannel_in_use = 0;
810 return ERR_PTR(-ENODEV);
814 * enable console I/O-interrupt subclass
816 isc_register(CONSOLE_ISC);
817 console_subchannel.config.isc = CONSOLE_ISC;
818 console_subchannel.config.intparm = (u32)(addr_t)&console_subchannel;
819 ret = cio_commit_config(&console_subchannel);
820 if (ret) {
821 isc_unregister(CONSOLE_ISC);
822 console_subchannel_in_use = 0;
823 return ERR_PTR(ret);
825 return &console_subchannel;
828 void
829 cio_release_console(void)
831 console_subchannel.config.intparm = 0;
832 cio_commit_config(&console_subchannel);
833 isc_unregister(CONSOLE_ISC);
834 console_subchannel_in_use = 0;
837 /* Bah... hack to catch console special sausages. */
839 cio_is_console(struct subchannel_id schid)
841 if (!console_subchannel_in_use)
842 return 0;
843 return schid_equal(&schid, &console_subchannel.schid);
846 struct subchannel *
847 cio_get_console_subchannel(void)
849 if (!console_subchannel_in_use)
850 return NULL;
851 return &console_subchannel;
854 #endif
855 static int
856 __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
858 int retry, cc;
860 cc = 0;
861 for (retry=0;retry<3;retry++) {
862 schib->pmcw.ena = 0;
863 cc = msch_err(schid, schib);
864 if (cc)
865 return (cc==3?-ENODEV:-EBUSY);
866 if (stsch_err(schid, schib) || !css_sch_is_valid(schib))
867 return -ENODEV;
868 if (!schib->pmcw.ena)
869 return 0;
871 return -EBUSY; /* uhm... */
874 static int
875 __clear_io_subchannel_easy(struct subchannel_id schid)
877 int retry;
879 if (csch(schid))
880 return -ENODEV;
881 for (retry=0;retry<20;retry++) {
882 struct tpi_info ti;
884 if (tpi(&ti)) {
885 tsch(ti.schid, (struct irb *)&S390_lowcore.irb);
886 if (schid_equal(&ti.schid, &schid))
887 return 0;
889 udelay_simple(100);
891 return -EBUSY;
894 static void __clear_chsc_subchannel_easy(void)
896 /* It seems we can only wait for a bit here :/ */
897 udelay_simple(100);
900 static int pgm_check_occured;
902 static void cio_reset_pgm_check_handler(void)
904 pgm_check_occured = 1;
907 static int stsch_reset(struct subchannel_id schid, struct schib *addr)
909 int rc;
911 pgm_check_occured = 0;
912 s390_base_pgm_handler_fn = cio_reset_pgm_check_handler;
913 rc = stsch_err(schid, addr);
914 s390_base_pgm_handler_fn = NULL;
916 /* The program check handler could have changed pgm_check_occured. */
917 barrier();
919 if (pgm_check_occured)
920 return -EIO;
921 else
922 return rc;
925 static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
927 struct schib schib;
929 if (stsch_reset(schid, &schib))
930 return -ENXIO;
931 if (!schib.pmcw.ena)
932 return 0;
933 switch(__disable_subchannel_easy(schid, &schib)) {
934 case 0:
935 case -ENODEV:
936 break;
937 default: /* -EBUSY */
938 switch (schib.pmcw.st) {
939 case SUBCHANNEL_TYPE_IO:
940 if (__clear_io_subchannel_easy(schid))
941 goto out; /* give up... */
942 break;
943 case SUBCHANNEL_TYPE_CHSC:
944 __clear_chsc_subchannel_easy();
945 break;
946 default:
947 /* No default clear strategy */
948 break;
950 stsch_err(schid, &schib);
951 __disable_subchannel_easy(schid, &schib);
953 out:
954 return 0;
957 static atomic_t chpid_reset_count;
959 static void s390_reset_chpids_mcck_handler(void)
961 struct crw crw;
962 struct mci *mci;
964 /* Check for pending channel report word. */
965 mci = (struct mci *)&S390_lowcore.mcck_interruption_code;
966 if (!mci->cp)
967 return;
968 /* Process channel report words. */
969 while (stcrw(&crw) == 0) {
970 /* Check for responses to RCHP. */
971 if (crw.slct && crw.rsc == CRW_RSC_CPATH)
972 atomic_dec(&chpid_reset_count);
976 #define RCHP_TIMEOUT (30 * USEC_PER_SEC)
977 static void css_reset(void)
979 int i, ret;
980 unsigned long long timeout;
981 struct chp_id chpid;
983 /* Reset subchannels. */
984 for_each_subchannel(__shutdown_subchannel_easy, NULL);
985 /* Reset channel paths. */
986 s390_base_mcck_handler_fn = s390_reset_chpids_mcck_handler;
987 /* Enable channel report machine checks. */
988 __ctl_set_bit(14, 28);
989 /* Temporarily reenable machine checks. */
990 local_mcck_enable();
991 chp_id_init(&chpid);
992 for (i = 0; i <= __MAX_CHPID; i++) {
993 chpid.id = i;
994 ret = rchp(chpid);
995 if ((ret == 0) || (ret == 2))
997 * rchp either succeeded, or another rchp is already
998 * in progress. In either case, we'll get a crw.
1000 atomic_inc(&chpid_reset_count);
1002 /* Wait for machine check for all channel paths. */
1003 timeout = get_clock() + (RCHP_TIMEOUT << 12);
1004 while (atomic_read(&chpid_reset_count) != 0) {
1005 if (get_clock() > timeout)
1006 break;
1007 cpu_relax();
1009 /* Disable machine checks again. */
1010 local_mcck_disable();
1011 /* Disable channel report machine checks. */
1012 __ctl_clear_bit(14, 28);
1013 s390_base_mcck_handler_fn = NULL;
1016 static struct reset_call css_reset_call = {
1017 .fn = css_reset,
1020 static int __init init_css_reset_call(void)
1022 atomic_set(&chpid_reset_count, 0);
1023 register_reset_call(&css_reset_call);
1024 return 0;
1027 arch_initcall(init_css_reset_call);
1029 struct sch_match_id {
1030 struct subchannel_id schid;
1031 struct ccw_dev_id devid;
1032 int rc;
1035 static int __reipl_subchannel_match(struct subchannel_id schid, void *data)
1037 struct schib schib;
1038 struct sch_match_id *match_id = data;
1040 if (stsch_reset(schid, &schib))
1041 return -ENXIO;
1042 if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv &&
1043 (schib.pmcw.dev == match_id->devid.devno) &&
1044 (schid.ssid == match_id->devid.ssid)) {
1045 match_id->schid = schid;
1046 match_id->rc = 0;
1047 return 1;
1049 return 0;
1052 static int reipl_find_schid(struct ccw_dev_id *devid,
1053 struct subchannel_id *schid)
1055 struct sch_match_id match_id;
1057 match_id.devid = *devid;
1058 match_id.rc = -ENODEV;
1059 for_each_subchannel(__reipl_subchannel_match, &match_id);
1060 if (match_id.rc == 0)
1061 *schid = match_id.schid;
1062 return match_id.rc;
1065 extern void do_reipl_asm(__u32 schid);
1067 /* Make sure all subchannels are quiet before we re-ipl an lpar. */
1068 void reipl_ccw_dev(struct ccw_dev_id *devid)
1070 struct subchannel_id schid;
1072 s390_reset_system(NULL, NULL);
1073 if (reipl_find_schid(devid, &schid) != 0)
1074 panic("IPL Device not found\n");
1075 do_reipl_asm(*((__u32*)&schid));
1078 int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo)
1080 struct subchannel_id schid;
1081 struct schib schib;
1083 schid = *(struct subchannel_id *)&S390_lowcore.subchannel_id;
1084 if (!schid.one)
1085 return -ENODEV;
1086 if (stsch_err(schid, &schib))
1087 return -ENODEV;
1088 if (schib.pmcw.st != SUBCHANNEL_TYPE_IO)
1089 return -ENODEV;
1090 if (!schib.pmcw.dnv)
1091 return -ENODEV;
1092 iplinfo->devno = schib.pmcw.dev;
1093 iplinfo->is_qdio = schib.pmcw.qf;
1094 return 0;
1098 * cio_tm_start_key - perform start function
1099 * @sch: subchannel on which to perform the start function
1100 * @tcw: transport-command word to be started
1101 * @lpm: mask of paths to use
1102 * @key: storage key to use for storage access
1104 * Start the tcw on the given subchannel. Return zero on success, non-zero
1105 * otherwise.
1107 int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key)
1109 int cc;
1110 union orb *orb = &to_io_private(sch)->orb;
1112 memset(orb, 0, sizeof(union orb));
1113 orb->tm.intparm = (u32) (addr_t) sch;
1114 orb->tm.key = key >> 4;
1115 orb->tm.b = 1;
1116 orb->tm.lpm = lpm ? lpm : sch->lpm;
1117 orb->tm.tcw = (u32) (addr_t) tcw;
1118 cc = ssch(sch->schid, orb);
1119 switch (cc) {
1120 case 0:
1121 return 0;
1122 case 1:
1123 case 2:
1124 return -EBUSY;
1125 default:
1126 return cio_start_handle_notoper(sch, lpm);
1131 * cio_tm_intrg - perform interrogate function
1132 * @sch - subchannel on which to perform the interrogate function
1134 * If the specified subchannel is running in transport-mode, perform the
1135 * interrogate function. Return zero on success, non-zero otherwie.
1137 int cio_tm_intrg(struct subchannel *sch)
1139 int cc;
1141 if (!to_io_private(sch)->orb.tm.b)
1142 return -EINVAL;
1143 cc = xsch(sch->schid);
1144 switch (cc) {
1145 case 0:
1146 case 2:
1147 return 0;
1148 case 1:
1149 return -EBUSY;
1150 default:
1151 return -ENODEV;