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 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/device.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/interrupt.h>
19 #include <asm/delay.h>
21 #include <asm/irq_regs.h>
22 #include <asm/setup.h>
23 #include <asm/reset.h>
25 #include <asm/chpid.h>
33 #include "blacklist.h"
34 #include "cio_debug.h"
36 #include "../s390mach.h"
38 debug_info_t *cio_debug_msg_id;
39 debug_info_t *cio_debug_trace_id;
40 debug_info_t *cio_debug_crw_id;
43 * Function: cio_debug_init
44 * Initializes three debug logs for common I/O:
45 * - cio_msg logs generic cio messages
46 * - cio_trace logs the calling of different functions
47 * - cio_crw logs machine check related cio messages
49 static int __init cio_debug_init(void)
51 cio_debug_msg_id = debug_register("cio_msg", 16, 1, 16 * sizeof(long));
52 if (!cio_debug_msg_id)
54 debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
55 debug_set_level(cio_debug_msg_id, 2);
56 cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
57 if (!cio_debug_trace_id)
59 debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
60 debug_set_level(cio_debug_trace_id, 2);
61 cio_debug_crw_id = debug_register("cio_crw", 16, 1, 16 * sizeof(long));
62 if (!cio_debug_crw_id)
64 debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
65 debug_set_level(cio_debug_crw_id, 4);
70 debug_unregister(cio_debug_msg_id);
71 if (cio_debug_trace_id)
72 debug_unregister(cio_debug_trace_id);
74 debug_unregister(cio_debug_crw_id);
75 printk(KERN_WARNING"cio: could not initialize debugging\n");
79 arch_initcall (cio_debug_init);
82 cio_set_options (struct subchannel *sch, int flags)
84 sch->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
85 sch->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
86 sch->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
90 /* FIXME: who wants to use this? */
92 cio_get_options (struct subchannel *sch)
97 if (sch->options.suspend)
98 flags |= DOIO_ALLOW_SUSPEND;
99 if (sch->options.prefetch)
100 flags |= DOIO_DENY_PREFETCH;
101 if (sch->options.inter)
102 flags |= DOIO_SUPPRESS_INTER;
107 * Use tpi to get a pending interrupt, call the interrupt handler and
108 * return a pointer to the subchannel structure.
113 struct tpi_info *tpi_info;
114 struct subchannel *sch;
117 tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
120 irb = (struct irb *) __LC_IRB;
121 /* Store interrupt response block to lowcore. */
122 if (tsch (tpi_info->schid, irb) != 0)
123 /* Not status pending or not operational. */
125 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
130 spin_lock(sch->lock);
131 memcpy (&sch->schib.scsw, &irb->scsw, sizeof (struct scsw));
132 if (sch->driver && sch->driver->irq)
133 sch->driver->irq(sch);
134 spin_unlock(sch->lock);
141 cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
150 stsch (sch->schid, &sch->schib);
152 CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
153 "subchannel 0.%x.%04x!\n", sch->schid.ssid,
155 sprintf(dbf_text, "no%s", sch->dev.bus_id);
156 CIO_TRACE_EVENT(0, dbf_text);
157 CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
159 return (sch->lpm ? -EACCES : -ENODEV);
163 cio_start_key (struct subchannel *sch, /* subchannel structure */
164 struct ccw1 * cpa, /* logical channel prog addr */
165 __u8 lpm, /* logical path mask */
166 __u8 key) /* storage key */
172 CIO_TRACE_EVENT(4, "stIO");
173 CIO_TRACE_EVENT(4, sch->dev.bus_id);
175 orb = &to_io_private(sch)->orb;
176 /* sch is always under 2G. */
177 orb->intparm = (u32)(addr_t)sch;
180 orb->pfch = sch->options.prefetch == 0;
181 orb->spnd = sch->options.suspend;
182 orb->ssic = sch->options.suspend && sch->options.inter;
183 orb->lpm = (lpm != 0) ? lpm : sch->lpm;
186 * for 64 bit we always support 64 bit IDAWs with 4k page size only
192 /* issue "Start Subchannel" */
193 orb->cpa = (__u32) __pa(cpa);
194 ccode = ssch(sch->schid, orb);
196 /* process condition code */
197 sprintf(dbf_txt, "ccode:%d", ccode);
198 CIO_TRACE_EVENT(4, dbf_txt);
203 * initialize device status information
205 sch->schib.scsw.actl |= SCSW_ACTL_START_PEND;
207 case 1: /* status pending */
210 default: /* device/path not operational */
211 return cio_start_handle_notoper(sch, lpm);
216 cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
218 return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
222 * resume suspended I/O operation
225 cio_resume (struct subchannel *sch)
230 CIO_TRACE_EVENT (4, "resIO");
231 CIO_TRACE_EVENT (4, sch->dev.bus_id);
233 ccode = rsch (sch->schid);
235 sprintf (dbf_txt, "ccode:%d", ccode);
236 CIO_TRACE_EVENT (4, dbf_txt);
240 sch->schib.scsw.actl |= SCSW_ACTL_RESUME_PEND;
248 * useless to wait for request completion
249 * as device is no longer operational !
259 cio_halt(struct subchannel *sch)
267 CIO_TRACE_EVENT (2, "haltIO");
268 CIO_TRACE_EVENT (2, sch->dev.bus_id);
271 * Issue "Halt subchannel" and process condition code
273 ccode = hsch (sch->schid);
275 sprintf (dbf_txt, "ccode:%d", ccode);
276 CIO_TRACE_EVENT (2, dbf_txt);
280 sch->schib.scsw.actl |= SCSW_ACTL_HALT_PEND;
282 case 1: /* status pending */
285 default: /* device not operational */
291 * Clear I/O operation
294 cio_clear(struct subchannel *sch)
302 CIO_TRACE_EVENT (2, "clearIO");
303 CIO_TRACE_EVENT (2, sch->dev.bus_id);
306 * Issue "Clear subchannel" and process condition code
308 ccode = csch (sch->schid);
310 sprintf (dbf_txt, "ccode:%d", ccode);
311 CIO_TRACE_EVENT (2, dbf_txt);
315 sch->schib.scsw.actl |= SCSW_ACTL_CLEAR_PEND;
317 default: /* device not operational */
323 * Function: cio_cancel
324 * Issues a "Cancel Subchannel" on the specified subchannel
325 * Note: We don't need any fancy intparms and flags here
326 * since xsch is executed synchronously.
327 * Only for common I/O internal use as for now.
330 cio_cancel (struct subchannel *sch)
338 CIO_TRACE_EVENT (2, "cancelIO");
339 CIO_TRACE_EVENT (2, sch->dev.bus_id);
341 ccode = xsch (sch->schid);
343 sprintf (dbf_txt, "ccode:%d", ccode);
344 CIO_TRACE_EVENT (2, dbf_txt);
347 case 0: /* success */
348 /* Update information in scsw. */
349 stsch (sch->schid, &sch->schib);
351 case 1: /* status pending */
353 case 2: /* not applicable */
355 default: /* not oper */
361 * Function: cio_modify
362 * Issues a "Modify Subchannel" on the specified subchannel
365 cio_modify (struct subchannel *sch)
367 int ccode, retry, ret;
370 for (retry = 0; retry < 5; retry++) {
371 ccode = msch_err (sch->schid, &sch->schib);
372 if (ccode < 0) /* -EIO if msch gets a program check. */
375 case 0: /* successfull */
377 case 1: /* status pending */
380 udelay (100); /* allow for recovery */
383 case 3: /* not operational */
393 int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
400 CIO_TRACE_EVENT (2, "ensch");
401 CIO_TRACE_EVENT (2, sch->dev.bus_id);
403 if (sch_is_pseudo_sch(sch))
405 ccode = stsch (sch->schid, &sch->schib);
409 for (retry = 5, ret = 0; retry > 0; retry--) {
410 sch->schib.pmcw.ena = 1;
411 sch->schib.pmcw.isc = sch->isc;
412 sch->schib.pmcw.intparm = intparm;
413 ret = cio_modify(sch);
418 * Got a program check in cio_modify. Try without
419 * the concurrent sense bit the next time.
421 sch->schib.pmcw.csense = 0;
423 stsch (sch->schid, &sch->schib);
424 if (sch->schib.pmcw.ena)
429 if (tsch(sch->schid, &irb) != 0)
433 sprintf (dbf_txt, "ret:%d", ret);
434 CIO_TRACE_EVENT (2, dbf_txt);
439 * Disable subchannel.
442 cio_disable_subchannel (struct subchannel *sch)
449 CIO_TRACE_EVENT (2, "dissch");
450 CIO_TRACE_EVENT (2, sch->dev.bus_id);
452 if (sch_is_pseudo_sch(sch))
454 ccode = stsch (sch->schid, &sch->schib);
455 if (ccode == 3) /* Not operational. */
458 if (sch->schib.scsw.actl != 0)
460 * the disable function must not be called while there are
461 * requests pending for completion !
465 for (retry = 5, ret = 0; retry > 0; retry--) {
466 sch->schib.pmcw.ena = 0;
467 ret = cio_modify(sch);
472 * The subchannel is busy or status pending.
473 * We'll disable when the next interrupt was delivered
474 * via the state machine.
478 stsch (sch->schid, &sch->schib);
479 if (!sch->schib.pmcw.ena)
483 sprintf (dbf_txt, "ret:%d", ret);
484 CIO_TRACE_EVENT (2, dbf_txt);
488 int cio_create_sch_lock(struct subchannel *sch)
490 sch->lock = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
493 spin_lock_init(sch->lock);
497 static int cio_validate_io_subchannel(struct subchannel *sch)
499 /* Initialization for io subchannels. */
500 if (!css_sch_is_valid(&sch->schib))
503 /* Devno is valid. */
504 if (is_blacklisted(sch->schid.ssid, sch->schib.pmcw.dev)) {
506 * This device must not be known to Linux. So we simply
507 * say that there is no device and return ENODEV.
509 CIO_MSG_EVENT(6, "Blacklisted device detected "
510 "at devno %04X, subchannel set %x\n",
511 sch->schib.pmcw.dev, sch->schid.ssid);
518 * cio_validate_subchannel - basic validation of subchannel
519 * @sch: subchannel structure to be filled out
520 * @schid: subchannel id
522 * Find out subchannel type and initialize struct subchannel.
525 * -ENXIO for non-defined subchannels
526 * -ENODEV for invalid subchannels or blacklisted devices
527 * -EIO for subchannels in an invalid subchannel set
529 int cio_validate_subchannel(struct subchannel *sch, struct subchannel_id schid)
535 sprintf(dbf_txt, "valsch%x", schid.sch_no);
536 CIO_TRACE_EVENT(4, dbf_txt);
538 /* Nuke all fields. */
539 memset(sch, 0, sizeof(struct subchannel));
542 if (cio_is_console(schid)) {
543 sch->lock = cio_get_console_lock();
545 err = cio_create_sch_lock(sch);
549 mutex_init(&sch->reg_mutex);
550 /* Set a name for the subchannel */
551 snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x", schid.ssid,
555 * The first subchannel that is not-operational (ccode==3)
556 * indicates that there aren't any more devices available.
557 * If stsch gets an exception, it means the current subchannel set
560 ccode = stsch_err (schid, &sch->schib);
562 err = (ccode == 3) ? -ENXIO : ccode;
565 /* Copy subchannel type from path management control word. */
566 sch->st = sch->schib.pmcw.st;
568 case SUBCHANNEL_TYPE_IO:
569 err = cio_validate_io_subchannel(sch);
577 CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n",
578 sch->schid.ssid, sch->schid.sch_no, sch->st);
581 if (!cio_is_console(schid))
588 * do_IRQ() handles all normal I/O device IRQ's (the special
589 * SMP cross-CPU interrupts have their own specific
594 do_IRQ (struct pt_regs *regs)
596 struct tpi_info *tpi_info;
597 struct subchannel *sch;
599 struct pt_regs *old_regs;
601 old_regs = set_irq_regs(regs);
604 if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
605 /* Serve timer interrupts first. */
606 clock_comparator_work();
608 * Get interrupt information from lowcore
610 tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
611 irb = (struct irb *) __LC_IRB;
613 kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
615 * Non I/O-subchannel thin interrupts are processed differently
617 if (tpi_info->adapter_IO == 1 &&
618 tpi_info->int_type == IO_INTERRUPT_TYPE) {
622 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
624 /* Clear pending interrupt condition. */
625 tsch(tpi_info->schid, irb);
628 spin_lock(sch->lock);
629 /* Store interrupt response block to lowcore. */
630 if (tsch(tpi_info->schid, irb) == 0) {
631 /* Keep subchannel information word up to date. */
632 memcpy (&sch->schib.scsw, &irb->scsw,
634 /* Call interrupt handler if there is one. */
635 if (sch->driver && sch->driver->irq)
636 sch->driver->irq(sch);
638 spin_unlock(sch->lock);
640 * Are more interrupts pending?
641 * If so, the tpi instruction will update the lowcore
642 * to hold the info for the next interrupt.
643 * We don't do this for VM because a tpi drops the cpu
644 * out of the sie which costs more cycles than it saves.
646 } while (!MACHINE_IS_VM && tpi (NULL) != 0);
648 set_irq_regs(old_regs);
651 #ifdef CONFIG_CCW_CONSOLE
652 static struct subchannel console_subchannel;
653 static struct io_subchannel_private console_priv;
654 static int console_subchannel_in_use;
656 void *cio_get_console_priv(void)
658 return &console_priv;
662 * busy wait for the next interrupt on the console
664 void wait_cons_dev(void)
665 __releases(console_subchannel.lock)
666 __acquires(console_subchannel.lock)
668 unsigned long cr6 __attribute__ ((aligned (8)));
669 unsigned long save_cr6 __attribute__ ((aligned (8)));
672 * before entering the spinlock we may already have
673 * processed the interrupt on a different CPU...
675 if (!console_subchannel_in_use)
678 /* disable all but isc 1 (console device) */
679 __ctl_store (save_cr6, 6, 6);
681 __ctl_load (cr6, 6, 6);
684 spin_unlock(console_subchannel.lock);
687 spin_lock(console_subchannel.lock);
688 } while (console_subchannel.schib.scsw.actl != 0);
690 * restore previous isc value
692 __ctl_load (save_cr6, 6, 6);
696 cio_test_for_console(struct subchannel_id schid, void *data)
698 if (stsch_err(schid, &console_subchannel.schib) != 0)
700 if ((console_subchannel.schib.pmcw.st == SUBCHANNEL_TYPE_IO) &&
701 console_subchannel.schib.pmcw.dnv &&
702 (console_subchannel.schib.pmcw.dev == console_devno)) {
703 console_irq = schid.sch_no;
704 return 1; /* found */
711 cio_get_console_sch_no(void)
713 struct subchannel_id schid;
715 init_subchannel_id(&schid);
716 if (console_irq != -1) {
717 /* VM provided us with the irq number of the console. */
718 schid.sch_no = console_irq;
719 if (stsch(schid, &console_subchannel.schib) != 0 ||
720 (console_subchannel.schib.pmcw.st != SUBCHANNEL_TYPE_IO) ||
721 !console_subchannel.schib.pmcw.dnv)
723 console_devno = console_subchannel.schib.pmcw.dev;
724 } else if (console_devno != -1) {
725 /* At least the console device number is known. */
726 for_each_subchannel(cio_test_for_console, NULL);
727 if (console_irq == -1)
730 /* unlike in 2.4, we cannot autoprobe here, since
731 * the channel subsystem is not fully initialized.
732 * With some luck, the HWC console can take over */
733 printk(KERN_WARNING "cio: No ccw console found!\n");
740 cio_probe_console(void)
743 struct subchannel_id schid;
745 if (xchg(&console_subchannel_in_use, 1) != 0)
746 return ERR_PTR(-EBUSY);
747 sch_no = cio_get_console_sch_no();
749 console_subchannel_in_use = 0;
750 return ERR_PTR(-ENODEV);
752 memset(&console_subchannel, 0, sizeof(struct subchannel));
753 init_subchannel_id(&schid);
754 schid.sch_no = sch_no;
755 ret = cio_validate_subchannel(&console_subchannel, schid);
757 console_subchannel_in_use = 0;
758 return ERR_PTR(-ENODEV);
762 * enable console I/O-interrupt subclass 1
765 console_subchannel.schib.pmcw.isc = 1;
766 console_subchannel.schib.pmcw.intparm =
767 (u32)(addr_t)&console_subchannel;
768 ret = cio_modify(&console_subchannel);
770 console_subchannel_in_use = 0;
773 return &console_subchannel;
777 cio_release_console(void)
779 console_subchannel.schib.pmcw.intparm = 0;
780 cio_modify(&console_subchannel);
781 ctl_clear_bit(6, 30);
782 console_subchannel_in_use = 0;
785 /* Bah... hack to catch console special sausages. */
787 cio_is_console(struct subchannel_id schid)
789 if (!console_subchannel_in_use)
791 return schid_equal(&schid, &console_subchannel.schid);
795 cio_get_console_subchannel(void)
797 if (!console_subchannel_in_use)
799 return &console_subchannel;
804 __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
809 for (retry=0;retry<3;retry++) {
811 cc = msch(schid, schib);
813 return (cc==3?-ENODEV:-EBUSY);
815 if (!schib->pmcw.ena)
818 return -EBUSY; /* uhm... */
821 /* we can't use the normal udelay here, since it enables external interrupts */
823 static void udelay_reset(unsigned long usecs)
825 uint64_t start_cc, end_cc;
827 asm volatile ("STCK %0" : "=m" (start_cc));
830 asm volatile ("STCK %0" : "=m" (end_cc));
831 } while (((end_cc - start_cc)/4096) < usecs);
835 __clear_io_subchannel_easy(struct subchannel_id schid)
841 for (retry=0;retry<20;retry++) {
845 tsch(ti.schid, (struct irb *)__LC_IRB);
846 if (schid_equal(&ti.schid, &schid))
854 static int pgm_check_occured;
856 static void cio_reset_pgm_check_handler(void)
858 pgm_check_occured = 1;
861 static int stsch_reset(struct subchannel_id schid, volatile struct schib *addr)
865 pgm_check_occured = 0;
866 s390_base_pgm_handler_fn = cio_reset_pgm_check_handler;
867 rc = stsch(schid, addr);
868 s390_base_pgm_handler_fn = NULL;
870 /* The program check handler could have changed pgm_check_occured. */
873 if (pgm_check_occured)
879 static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
883 if (stsch_reset(schid, &schib))
887 switch(__disable_subchannel_easy(schid, &schib)) {
891 default: /* -EBUSY */
892 switch (schib.pmcw.st) {
893 case SUBCHANNEL_TYPE_IO:
894 if (__clear_io_subchannel_easy(schid))
895 goto out; /* give up... */
898 /* No default clear strategy */
901 stsch(schid, &schib);
902 __disable_subchannel_easy(schid, &schib);
908 static atomic_t chpid_reset_count;
910 static void s390_reset_chpids_mcck_handler(void)
915 /* Check for pending channel report word. */
916 mci = (struct mci *)&S390_lowcore.mcck_interruption_code;
919 /* Process channel report words. */
920 while (stcrw(&crw) == 0) {
921 /* Check for responses to RCHP. */
922 if (crw.slct && crw.rsc == CRW_RSC_CPATH)
923 atomic_dec(&chpid_reset_count);
927 #define RCHP_TIMEOUT (30 * USEC_PER_SEC)
928 static void css_reset(void)
931 unsigned long long timeout;
934 /* Reset subchannels. */
935 for_each_subchannel(__shutdown_subchannel_easy, NULL);
936 /* Reset channel paths. */
937 s390_base_mcck_handler_fn = s390_reset_chpids_mcck_handler;
938 /* Enable channel report machine checks. */
939 __ctl_set_bit(14, 28);
940 /* Temporarily reenable machine checks. */
943 for (i = 0; i <= __MAX_CHPID; i++) {
946 if ((ret == 0) || (ret == 2))
948 * rchp either succeeded, or another rchp is already
949 * in progress. In either case, we'll get a crw.
951 atomic_inc(&chpid_reset_count);
953 /* Wait for machine check for all channel paths. */
954 timeout = get_clock() + (RCHP_TIMEOUT << 12);
955 while (atomic_read(&chpid_reset_count) != 0) {
956 if (get_clock() > timeout)
960 /* Disable machine checks again. */
961 local_mcck_disable();
962 /* Disable channel report machine checks. */
963 __ctl_clear_bit(14, 28);
964 s390_base_mcck_handler_fn = NULL;
967 static struct reset_call css_reset_call = {
971 static int __init init_css_reset_call(void)
973 atomic_set(&chpid_reset_count, 0);
974 register_reset_call(&css_reset_call);
978 arch_initcall(init_css_reset_call);
980 struct sch_match_id {
981 struct subchannel_id schid;
982 struct ccw_dev_id devid;
986 static int __reipl_subchannel_match(struct subchannel_id schid, void *data)
989 struct sch_match_id *match_id = data;
991 if (stsch_reset(schid, &schib))
993 if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv &&
994 (schib.pmcw.dev == match_id->devid.devno) &&
995 (schid.ssid == match_id->devid.ssid)) {
996 match_id->schid = schid;
1003 static int reipl_find_schid(struct ccw_dev_id *devid,
1004 struct subchannel_id *schid)
1006 struct sch_match_id match_id;
1008 match_id.devid = *devid;
1009 match_id.rc = -ENODEV;
1010 for_each_subchannel(__reipl_subchannel_match, &match_id);
1011 if (match_id.rc == 0)
1012 *schid = match_id.schid;
1016 extern void do_reipl_asm(__u32 schid);
1018 /* Make sure all subchannels are quiet before we re-ipl an lpar. */
1019 void reipl_ccw_dev(struct ccw_dev_id *devid)
1021 struct subchannel_id schid;
1023 s390_reset_system();
1024 if (reipl_find_schid(devid, &schid) != 0)
1025 panic("IPL Device not found\n");
1026 do_reipl_asm(*((__u32*)&schid));
1029 int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo)
1031 struct subchannel_id schid;
1034 schid = *(struct subchannel_id *)__LC_SUBCHANNEL_ID;
1037 if (stsch(schid, &schib))
1039 if (schib.pmcw.st != SUBCHANNEL_TYPE_IO)
1041 if (!schib.pmcw.dnv)
1043 iplinfo->devno = schib.pmcw.dev;
1044 iplinfo->is_qdio = schib.pmcw.qf;