drivers/s390/cio/cio.c

   1 /*
   2  *  drivers/s390/cio/cio.c
   3  *   S/390 common I/O routines -- low level i/o calls
   4  *
   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)
  10  */
  11
  12 #define KMSG_COMPONENT "cio"
  13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  14
  15 #include <linux/module.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 #include <asm/cio.h>
  22 #include <asm/delay.h>
  23 #include <asm/irq.h>
  24 #include <asm/irq_regs.h>
  25 #include <asm/setup.h>
  26 #include <asm/reset.h>
  27 #include <asm/ipl.h>
  28 #include <asm/chpid.h>
  29 #include <asm/airq.h>
  30 #include <asm/isc.h>
  31 #include <asm/cpu.h>
  32 #include <asm/fcx.h>
  33 #include "cio.h"
  34 #include "css.h"
  35 #include "chsc.h"
  36 #include "ioasm.h"
  37 #include "io_sch.h"
  38 #include "blacklist.h"
  39 #include "cio_debug.h"
  40 #include "chp.h"
  41 #include "../s390mach.h"
  42
  43 debug_info_t *cio_debug_msg_id;
  44 debug_info_t *cio_debug_trace_id;
  45 debug_info_t *cio_debug_crw_id;
  46
  47 /*
  48  * Function: cio_debug_init
  49  * Initializes three debug logs for common I/O:
  50  * - cio_msg logs generic cio messages
  51  * - cio_trace logs the calling of different functions
  52  * - cio_crw logs machine check related cio messages
  53  */
  54 static int __init cio_debug_init(void)
  55 {
  56         cio_debug_msg_id = debug_register("cio_msg", 16, 1, 16 * sizeof(long));
  57         if (!cio_debug_msg_id)
  58                 goto out_unregister;
  59         debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
  60         debug_set_level(cio_debug_msg_id, 2);
  61         cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
  62         if (!cio_debug_trace_id)
  63                 goto out_unregister;
  64         debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
  65         debug_set_level(cio_debug_trace_id, 2);
  66         cio_debug_crw_id = debug_register("cio_crw", 16, 1, 16 * sizeof(long));
  67         if (!cio_debug_crw_id)
  68                 goto out_unregister;
  69         debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
  70         debug_set_level(cio_debug_crw_id, 4);
  71         return 0;
  72
  73 out_unregister:
  74         if (cio_debug_msg_id)
  75                 debug_unregister(cio_debug_msg_id);
  76         if (cio_debug_trace_id)
  77                 debug_unregister(cio_debug_trace_id);
  78         if (cio_debug_crw_id)
  79                 debug_unregister(cio_debug_crw_id);
  80         return -1;
  81 }
  82
  83 arch_initcall (cio_debug_init);
  84
  85 int
  86 cio_set_options (struct subchannel *sch, int flags)
  87 {
  88        sch->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
  89        sch->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
  90        sch->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
  91        return 0;
  92 }
  93
  94 /* FIXME: who wants to use this? */
  95 int
  96 cio_get_options (struct subchannel *sch)
  97 {
  98        int flags;
  99
 100        flags = 0;
 101        if (sch->options.suspend)
 102                 flags |= DOIO_ALLOW_SUSPEND;
 103        if (sch->options.prefetch)
 104                 flags |= DOIO_DENY_PREFETCH;
 105        if (sch->options.inter)
 106                 flags |= DOIO_SUPPRESS_INTER;
 107        return flags;
 108 }
 109
 110 static int
 111 cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
 112 {
 113         char dbf_text[15];
 114
 115         if (lpm != 0)
 116                 sch->lpm &= ~lpm;
 117         else
 118                 sch->lpm = 0;
 119
 120         CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
 121                       "subchannel 0.%x.%04x!\n", sch->schid.ssid,
 122                       sch->schid.sch_no);
 123
 124         if (cio_update_schib(sch))
 125                 return -ENODEV;
 126
 127         sprintf(dbf_text, "no%s", dev_name(&sch->dev));
 128         CIO_TRACE_EVENT(0, dbf_text);
 129         CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
 130
 131         return (sch->lpm ? -EACCES : -ENODEV);
 132 }
 133
 134 int
 135 cio_start_key (struct subchannel *sch,  /* subchannel structure */
 136                struct ccw1 * cpa,       /* logical channel prog addr */
 137                __u8 lpm,                /* logical path mask */
 138                __u8 key)                /* storage key */
 139 {
 140         char dbf_txt[15];
 141         int ccode;
 142         union orb *orb;
 143
 144         CIO_TRACE_EVENT(4, "stIO");
 145         CIO_TRACE_EVENT(4, dev_name(&sch->dev));
 146
 147         orb = &to_io_private(sch)->orb;
 148         memset(orb, 0, sizeof(union orb));
 149         /* sch is always under 2G. */
 150         orb->cmd.intparm = (u32)(addr_t)sch;
 151         orb->cmd.fmt = 1;
 152
 153         orb->cmd.pfch = sch->options.prefetch == 0;
 154         orb->cmd.spnd = sch->options.suspend;
 155         orb->cmd.ssic = sch->options.suspend && sch->options.inter;
 156         orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm;
 157 #ifdef CONFIG_64BIT
 158         /*
 159          * for 64 bit we always support 64 bit IDAWs with 4k page size only
 160          */
 161         orb->cmd.c64 = 1;
 162         orb->cmd.i2k = 0;
 163 #endif
 164         orb->cmd.key = key >> 4;
 165         /* issue "Start Subchannel" */
 166         orb->cmd.cpa = (__u32) __pa(cpa);
 167         ccode = ssch(sch->schid, orb);
 168
 169         /* process condition code */
 170         sprintf(dbf_txt, "ccode:%d", ccode);
 171         CIO_TRACE_EVENT(4, dbf_txt);
 172
 173         switch (ccode) {
 174         case 0:
 175                 /*
 176                  * initialize device status information
 177                  */
 178                 sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND;
 179                 return 0;
 180         case 1:         /* status pending */
 181         case 2:         /* busy */
 182                 return -EBUSY;
 183         case 3:         /* device/path not operational */
 184                 return cio_start_handle_notoper(sch, lpm);
 185         default:
 186                 return ccode;
 187         }
 188 }
 189
 190 int
 191 cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
 192 {
 193         return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
 194 }
 195
 196 /*
 197  * resume suspended I/O operation
 198  */
 199 int
 200 cio_resume (struct subchannel *sch)
 201 {
 202         char dbf_txt[15];
 203         int ccode;
 204
 205         CIO_TRACE_EVENT (4, "resIO");
 206         CIO_TRACE_EVENT(4, dev_name(&sch->dev));
 207
 208         ccode = rsch (sch->schid);
 209
 210         sprintf (dbf_txt, "ccode:%d", ccode);
 211         CIO_TRACE_EVENT (4, dbf_txt);
 212
 213         switch (ccode) {
 214         case 0:
 215                 sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND;
 216                 return 0;
 217         case 1:
 218                 return -EBUSY;
 219         case 2:
 220                 return -EINVAL;
 221         default:
 222                 /*
 223                  * useless to wait for request completion
 224                  *  as device is no longer operational !
 225                  */
 226                 return -ENODEV;
 227         }
 228 }
 229
 230 /*
 231  * halt I/O operation
 232  */
 233 int
 234 cio_halt(struct subchannel *sch)
 235 {
 236         char dbf_txt[15];
 237         int ccode;
 238
 239         if (!sch)
 240                 return -ENODEV;
 241
 242         CIO_TRACE_EVENT (2, "haltIO");
 243         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
 244
 245         /*
 246          * Issue "Halt subchannel" and process condition code
 247          */
 248         ccode = hsch (sch->schid);
 249
 250         sprintf (dbf_txt, "ccode:%d", ccode);
 251         CIO_TRACE_EVENT (2, dbf_txt);
 252
 253         switch (ccode) {
 254         case 0:
 255                 sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND;
 256                 return 0;
 257         case 1:         /* status pending */
 258         case 2:         /* busy */
 259                 return -EBUSY;
 260         default:                /* device not operational */
 261                 return -ENODEV;
 262         }
 263 }
 264
 265 /*
 266  * Clear I/O operation
 267  */
 268 int
 269 cio_clear(struct subchannel *sch)
 270 {
 271         char dbf_txt[15];
 272         int ccode;
 273
 274         if (!sch)
 275                 return -ENODEV;
 276
 277         CIO_TRACE_EVENT (2, "clearIO");
 278         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
 279
 280         /*
 281          * Issue "Clear subchannel" and process condition code
 282          */
 283         ccode = csch (sch->schid);
 284
 285         sprintf (dbf_txt, "ccode:%d", ccode);
 286         CIO_TRACE_EVENT (2, dbf_txt);
 287
 288         switch (ccode) {
 289         case 0:
 290                 sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND;
 291                 return 0;
 292         default:                /* device not operational */
 293                 return -ENODEV;
 294         }
 295 }
 296
 297 /*
 298  * Function: cio_cancel
 299  * Issues a "Cancel Subchannel" on the specified subchannel
 300  * Note: We don't need any fancy intparms and flags here
 301  *       since xsch is executed synchronously.
 302  * Only for common I/O internal use as for now.
 303  */
 304 int
 305 cio_cancel (struct subchannel *sch)
 306 {
 307         char dbf_txt[15];
 308         int ccode;
 309
 310         if (!sch)
 311                 return -ENODEV;
 312
 313         CIO_TRACE_EVENT (2, "cancelIO");
 314         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
 315
 316         ccode = xsch (sch->schid);
 317
 318         sprintf (dbf_txt, "ccode:%d", ccode);
 319         CIO_TRACE_EVENT (2, dbf_txt);
 320
 321         switch (ccode) {
 322         case 0:         /* success */
 323                 /* Update information in scsw. */
 324                 if (cio_update_schib(sch))
 325                         return -ENODEV;
 326                 return 0;
 327         case 1:         /* status pending */
 328                 return -EBUSY;
 329         case 2:         /* not applicable */
 330                 return -EINVAL;
 331         default:        /* not oper */
 332                 return -ENODEV;
 333         }
 334 }
 335
 336
 337 static void cio_apply_config(struct subchannel *sch, struct schib *schib)
 338 {
 339         schib->pmcw.intparm = sch->config.intparm;
 340         schib->pmcw.mbi = sch->config.mbi;
 341         schib->pmcw.isc = sch->config.isc;
 342         schib->pmcw.ena = sch->config.ena;
 343         schib->pmcw.mme = sch->config.mme;
 344         schib->pmcw.mp = sch->config.mp;
 345         schib->pmcw.csense = sch->config.csense;
 346         schib->pmcw.mbfc = sch->config.mbfc;
 347         if (sch->config.mbfc)
 348                 schib->mba = sch->config.mba;
 349 }
 350
 351 static int cio_check_config(struct subchannel *sch, struct schib *schib)
 352 {
 353         return (schib->pmcw.intparm == sch->config.intparm) &&
 354                 (schib->pmcw.mbi == sch->config.mbi) &&
 355                 (schib->pmcw.isc == sch->config.isc) &&
 356                 (schib->pmcw.ena == sch->config.ena) &&
 357                 (schib->pmcw.mme == sch->config.mme) &&
 358                 (schib->pmcw.mp == sch->config.mp) &&
 359                 (schib->pmcw.csense == sch->config.csense) &&
 360                 (schib->pmcw.mbfc == sch->config.mbfc) &&
 361                 (!sch->config.mbfc || (schib->mba == sch->config.mba));
 362 }
 363
 364 /*
 365  * cio_commit_config - apply configuration to the subchannel
 366  */
 367 int cio_commit_config(struct subchannel *sch)
 368 {
 369         struct schib schib;
 370         int ccode, retry, ret = 0;
 371
 372         if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
 373                 return -ENODEV;
 374
 375         for (retry = 0; retry < 5; retry++) {
 376                 /* copy desired changes to local schib */
 377                 cio_apply_config(sch, &schib);
 378                 ccode = msch_err(sch->schid, &schib);
 379                 if (ccode < 0) /* -EIO if msch gets a program check. */
 380                         return ccode;
 381                 switch (ccode) {
 382                 case 0: /* successfull */
 383                         if (stsch(sch->schid, &schib) ||
 384                             !css_sch_is_valid(&schib))
 385                                 return -ENODEV;
 386                         if (cio_check_config(sch, &schib)) {
 387                                 /* commit changes from local schib */
 388                                 memcpy(&sch->schib, &schib, sizeof(schib));
 389                                 return 0;
 390                         }
 391                         ret = -EAGAIN;
 392                         break;
 393                 case 1: /* status pending */
 394                         return -EBUSY;
 395                 case 2: /* busy */
 396                         udelay(100); /* allow for recovery */
 397                         ret = -EBUSY;
 398                         break;
 399                 case 3: /* not operational */
 400                         return -ENODEV;
 401                 }
 402         }
 403         return ret;
 404 }
 405
 406 /**
 407  * cio_update_schib - Perform stsch and update schib if subchannel is valid.
 408  * @sch: subchannel on which to perform stsch
 409  * Return zero on success, -ENODEV otherwise.
 410  */
 411 int cio_update_schib(struct subchannel *sch)
 412 {
 413         struct schib schib;
 414
 415         if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
 416                 return -ENODEV;
 417
 418         memcpy(&sch->schib, &schib, sizeof(schib));
 419         return 0;
 420 }
 421 EXPORT_SYMBOL_GPL(cio_update_schib);
 422
 423 /**
 424  * cio_enable_subchannel - enable a subchannel.
 425  * @sch: subchannel to be enabled
 426  * @intparm: interruption parameter to set
 427  */
 428 int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
 429 {
 430         char dbf_txt[15];
 431         int retry;
 432         int ret;
 433
 434         CIO_TRACE_EVENT (2, "ensch");
 435         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
 436
 437         if (sch_is_pseudo_sch(sch))
 438                 return -EINVAL;
 439         if (cio_update_schib(sch))
 440                 return -ENODEV;
 441
 442         sch->config.ena = 1;
 443         sch->config.isc = sch->isc;
 444         sch->config.intparm = intparm;
 445
 446         for (retry = 0; retry < 3; retry++) {
 447                 ret = cio_commit_config(sch);
 448                 if (ret == -EIO) {
 449                         /*
 450                          * Got a program check in msch. Try without
 451                          * the concurrent sense bit the next time.
 452                          */
 453                         sch->config.csense = 0;
 454                 } else if (ret == -EBUSY) {
 455                         struct irb irb;
 456                         if (tsch(sch->schid, &irb) != 0)
 457                                 break;
 458                 } else
 459                         break;
 460         }
 461         sprintf (dbf_txt, "ret:%d", ret);
 462         CIO_TRACE_EVENT (2, dbf_txt);
 463         return ret;
 464 }
 465 EXPORT_SYMBOL_GPL(cio_enable_subchannel);
 466
 467 /**
 468  * cio_disable_subchannel - disable a subchannel.
 469  * @sch: subchannel to disable
 470  */
 471 int cio_disable_subchannel(struct subchannel *sch)
 472 {
 473         char dbf_txt[15];
 474         int ret;
 475
 476         CIO_TRACE_EVENT (2, "dissch");
 477         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
 478
 479         if (sch_is_pseudo_sch(sch))
 480                 return 0;
 481         if (cio_update_schib(sch))
 482                 return -ENODEV;
 483
 484         if (scsw_actl(&sch->schib.scsw) != 0)
 485                 /*
 486                  * the disable function must not be called while there are
 487                  *  requests pending for completion !
 488                  */
 489                 return -EBUSY;
 490
 491         sch->config.ena = 0;
 492         ret = cio_commit_config(sch);
 493
 494         sprintf (dbf_txt, "ret:%d", ret);
 495         CIO_TRACE_EVENT (2, dbf_txt);
 496         return ret;
 497 }
 498 EXPORT_SYMBOL_GPL(cio_disable_subchannel);
 499
 500 int cio_create_sch_lock(struct subchannel *sch)
 501 {
 502         sch->lock = kmalloc(sizeof(spinlock_t), GFP_KERNEL);
 503         if (!sch->lock)
 504                 return -ENOMEM;
 505         spin_lock_init(sch->lock);
 506         return 0;
 507 }
 508
 509 static int cio_check_devno_blacklisted(struct subchannel *sch)
 510 {
 511         if (is_blacklisted(sch->schid.ssid, sch->schib.pmcw.dev)) {
 512                 /*
 513                  * This device must not be known to Linux. So we simply
 514                  * say that there is no device and return ENODEV.
 515                  */
 516                 CIO_MSG_EVENT(6, "Blacklisted device detected "
 517                               "at devno %04X, subchannel set %x\n",
 518                               sch->schib.pmcw.dev, sch->schid.ssid);
 519                 return -ENODEV;
 520         }
 521         return 0;
 522 }
 523
 524 static int cio_validate_io_subchannel(struct subchannel *sch)
 525 {
 526         /* Initialization for io subchannels. */
 527         if (!css_sch_is_valid(&sch->schib))
 528                 return -ENODEV;
 529
 530         /* Devno is valid. */
 531         return cio_check_devno_blacklisted(sch);
 532 }
 533
 534 static int cio_validate_msg_subchannel(struct subchannel *sch)
 535 {
 536         /* Initialization for message subchannels. */
 537         if (!css_sch_is_valid(&sch->schib))
 538                 return -ENODEV;
 539
 540         /* Devno is valid. */
 541         return cio_check_devno_blacklisted(sch);
 542 }
 543
 544 /**
 545  * cio_validate_subchannel - basic validation of subchannel
 546  * @sch: subchannel structure to be filled out
 547  * @schid: subchannel id
 548  *
 549  * Find out subchannel type and initialize struct subchannel.
 550  * Return codes:
 551  *   0 on success
 552  *   -ENXIO for non-defined subchannels
 553  *   -ENODEV for invalid subchannels or blacklisted devices
 554  *   -EIO for subchannels in an invalid subchannel set
 555  */
 556 int cio_validate_subchannel(struct subchannel *sch, struct subchannel_id schid)
 557 {
 558         char dbf_txt[15];
 559         int ccode;
 560         int err;
 561
 562         sprintf(dbf_txt, "valsch%x", schid.sch_no);
 563         CIO_TRACE_EVENT(4, dbf_txt);
 564
 565         /* Nuke all fields. */
 566         memset(sch, 0, sizeof(struct subchannel));
 567
 568         sch->schid = schid;
 569         if (cio_is_console(schid)) {
 570                 sch->lock = cio_get_console_lock();
 571         } else {
 572                 err = cio_create_sch_lock(sch);
 573                 if (err)
 574                         goto out;
 575         }
 576         mutex_init(&sch->reg_mutex);
 577         /* Set a name for the subchannel */
 578         if (cio_is_console(schid))
 579                 sch->dev.init_name = cio_get_console_sch_name(schid);
 580         else
 581                 dev_set_name(&sch->dev, "0.%x.%04x", schid.ssid, schid.sch_no);
 582
 583         /*
 584          * The first subchannel that is not-operational (ccode==3)
 585          *  indicates that there aren't any more devices available.
 586          * If stsch gets an exception, it means the current subchannel set
 587          *  is not valid.
 588          */
 589         ccode = stsch_err (schid, &sch->schib);
 590         if (ccode) {
 591                 err = (ccode == 3) ? -ENXIO : ccode;
 592                 goto out;
 593         }
 594         /* Copy subchannel type from path management control word. */
 595         sch->st = sch->schib.pmcw.st;
 596
 597         switch (sch->st) {
 598         case SUBCHANNEL_TYPE_IO:
 599                 err = cio_validate_io_subchannel(sch);
 600                 break;
 601         case SUBCHANNEL_TYPE_MSG:
 602                 err = cio_validate_msg_subchannel(sch);
 603                 break;
 604         default:
 605                 err = 0;
 606         }
 607         if (err)
 608                 goto out;
 609
 610         CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n",
 611                       sch->schid.ssid, sch->schid.sch_no, sch->st);
 612         return 0;
 613 out:
 614         if (!cio_is_console(schid))
 615                 kfree(sch->lock);
 616         sch->lock = NULL;
 617         return err;
 618 }
 619
 620 /*
 621  * do_IRQ() handles all normal I/O device IRQ's (the special
 622  *          SMP cross-CPU interrupts have their own specific
 623  *          handlers).
 624  *
 625  */
 626 void
 627 do_IRQ (struct pt_regs *regs)
 628 {
 629         struct tpi_info *tpi_info;
 630         struct subchannel *sch;
 631         struct irb *irb;
 632         struct pt_regs *old_regs;
 633
 634         old_regs = set_irq_regs(regs);
 635         s390_idle_check();
 636         irq_enter();
 637         if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
 638                 /* Serve timer interrupts first. */
 639                 clock_comparator_work();
 640         /*
 641          * Get interrupt information from lowcore
 642          */
 643         tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
 644         irb = (struct irb *) __LC_IRB;
 645         do {
 646                 kstat_cpu(smp_processor_id()).irqs[IO_INTERRUPT]++;
 647                 /*
 648                  * Non I/O-subchannel thin interrupts are processed differently
 649                  */
 650                 if (tpi_info->adapter_IO == 1 &&
 651                     tpi_info->int_type == IO_INTERRUPT_TYPE) {
 652                         do_adapter_IO(tpi_info->isc);
 653                         continue;
 654                 }
 655                 sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
 656                 if (!sch) {
 657                         /* Clear pending interrupt condition. */
 658                         tsch(tpi_info->schid, irb);
 659                         continue;
 660                 }
 661                 spin_lock(sch->lock);
 662                 /* Store interrupt response block to lowcore. */
 663                 if (tsch(tpi_info->schid, irb) == 0) {
 664                         /* Keep subchannel information word up to date. */
 665                         memcpy (&sch->schib.scsw, &irb->scsw,
 666                                 sizeof (irb->scsw));
 667                         /* Call interrupt handler if there is one. */
 668                         if (sch->driver && sch->driver->irq)
 669                                 sch->driver->irq(sch);
 670                 }
 671                 spin_unlock(sch->lock);
 672                 /*
 673                  * Are more interrupts pending?
 674                  * If so, the tpi instruction will update the lowcore
 675                  * to hold the info for the next interrupt.
 676                  * We don't do this for VM because a tpi drops the cpu
 677                  * out of the sie which costs more cycles than it saves.
 678                  */
 679         } while (!MACHINE_IS_VM && tpi (NULL) != 0);
 680         irq_exit();
 681         set_irq_regs(old_regs);
 682 }
 683
 684 #ifdef CONFIG_CCW_CONSOLE
 685 static struct subchannel console_subchannel;
 686 static char console_sch_name[10] = "0.x.xxxx";
 687 static struct io_subchannel_private console_priv;
 688 static int console_subchannel_in_use;
 689
 690 /*
 691  * Use tpi to get a pending interrupt, call the interrupt handler and
 692  * return a pointer to the subchannel structure.
 693  */
 694 static int cio_tpi(void)
 695 {
 696         struct tpi_info *tpi_info;
 697         struct subchannel *sch;
 698         struct irb *irb;
 699         int irq_context;
 700
 701         tpi_info = (struct tpi_info *) __LC_SUBCHANNEL_ID;
 702         if (tpi(NULL) != 1)
 703                 return 0;
 704         irb = (struct irb *) __LC_IRB;
 705         /* Store interrupt response block to lowcore. */
 706         if (tsch(tpi_info->schid, irb) != 0)
 707                 /* Not status pending or not operational. */
 708                 return 1;
 709         sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
 710         if (!sch)
 711                 return 1;
 712         irq_context = in_interrupt();
 713         if (!irq_context)
 714                 local_bh_disable();
 715         irq_enter();
 716         spin_lock(sch->lock);
 717         memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
 718         if (sch->driver && sch->driver->irq)
 719                 sch->driver->irq(sch);
 720         spin_unlock(sch->lock);
 721         irq_exit();
 722         if (!irq_context)
 723                 _local_bh_enable();
 724         return 1;
 725 }
 726
 727 void *cio_get_console_priv(void)
 728 {
 729         return &console_priv;
 730 }
 731
 732 /*
 733  * busy wait for the next interrupt on the console
 734  */
 735 void wait_cons_dev(void)
 736         __releases(console_subchannel.lock)
 737         __acquires(console_subchannel.lock)
 738 {
 739         unsigned long cr6      __attribute__ ((aligned (8)));
 740         unsigned long save_cr6 __attribute__ ((aligned (8)));
 741
 742         /*
 743          * before entering the spinlock we may already have
 744          * processed the interrupt on a different CPU...
 745          */
 746         if (!console_subchannel_in_use)
 747                 return;
 748
 749         /* disable all but the console isc */
 750         __ctl_store (save_cr6, 6, 6);
 751         cr6 = 1UL << (31 - CONSOLE_ISC);
 752         __ctl_load (cr6, 6, 6);
 753
 754         do {
 755                 spin_unlock(console_subchannel.lock);
 756                 if (!cio_tpi())
 757                         cpu_relax();
 758                 spin_lock(console_subchannel.lock);
 759         } while (console_subchannel.schib.scsw.cmd.actl != 0);
 760         /*
 761          * restore previous isc value
 762          */
 763         __ctl_load (save_cr6, 6, 6);
 764 }
 765
 766 static int
 767 cio_test_for_console(struct subchannel_id schid, void *data)
 768 {
 769         if (stsch_err(schid, &console_subchannel.schib) != 0)
 770                 return -ENXIO;
 771         if ((console_subchannel.schib.pmcw.st == SUBCHANNEL_TYPE_IO) &&
 772             console_subchannel.schib.pmcw.dnv &&
 773             (console_subchannel.schib.pmcw.dev == console_devno)) {
 774                 console_irq = schid.sch_no;
 775                 return 1; /* found */
 776         }
 777         return 0;
 778 }
 779
 780
 781 static int
 782 cio_get_console_sch_no(void)
 783 {
 784         struct subchannel_id schid;
 785
 786         init_subchannel_id(&schid);
 787         if (console_irq != -1) {
 788                 /* VM provided us with the irq number of the console. */
 789                 schid.sch_no = console_irq;
 790                 if (stsch(schid, &console_subchannel.schib) != 0 ||
 791                     (console_subchannel.schib.pmcw.st != SUBCHANNEL_TYPE_IO) ||
 792                     !console_subchannel.schib.pmcw.dnv)
 793                         return -1;
 794                 console_devno = console_subchannel.schib.pmcw.dev;
 795         } else if (console_devno != -1) {
 796                 /* At least the console device number is known. */
 797                 for_each_subchannel(cio_test_for_console, NULL);
 798                 if (console_irq == -1)
 799                         return -1;
 800         } else {
 801                 /* unlike in 2.4, we cannot autoprobe here, since
 802                  * the channel subsystem is not fully initialized.
 803                  * With some luck, the HWC console can take over */
 804                 return -1;
 805         }
 806         return console_irq;
 807 }
 808
 809 struct subchannel *
 810 cio_probe_console(void)
 811 {
 812         int sch_no, ret;
 813         struct subchannel_id schid;
 814
 815         if (xchg(&console_subchannel_in_use, 1) != 0)
 816                 return ERR_PTR(-EBUSY);
 817         sch_no = cio_get_console_sch_no();
 818         if (sch_no == -1) {
 819                 console_subchannel_in_use = 0;
 820                 pr_warning("No CCW console was found\n");
 821                 return ERR_PTR(-ENODEV);
 822         }
 823         memset(&console_subchannel, 0, sizeof(struct subchannel));
 824         init_subchannel_id(&schid);
 825         schid.sch_no = sch_no;
 826         ret = cio_validate_subchannel(&console_subchannel, schid);
 827         if (ret) {
 828                 console_subchannel_in_use = 0;
 829                 return ERR_PTR(-ENODEV);
 830         }
 831
 832         /*
 833          * enable console I/O-interrupt subclass
 834          */
 835         isc_register(CONSOLE_ISC);
 836         console_subchannel.config.isc = CONSOLE_ISC;
 837         console_subchannel.config.intparm = (u32)(addr_t)&console_subchannel;
 838         ret = cio_commit_config(&console_subchannel);
 839         if (ret) {
 840                 isc_unregister(CONSOLE_ISC);
 841                 console_subchannel_in_use = 0;
 842                 return ERR_PTR(ret);
 843         }
 844         return &console_subchannel;
 845 }
 846
 847 void
 848 cio_release_console(void)
 849 {
 850         console_subchannel.config.intparm = 0;
 851         cio_commit_config(&console_subchannel);
 852         isc_unregister(CONSOLE_ISC);
 853         console_subchannel_in_use = 0;
 854 }
 855
 856 /* Bah... hack to catch console special sausages. */
 857 int
 858 cio_is_console(struct subchannel_id schid)
 859 {
 860         if (!console_subchannel_in_use)
 861                 return 0;
 862         return schid_equal(&schid, &console_subchannel.schid);
 863 }
 864
 865 struct subchannel *
 866 cio_get_console_subchannel(void)
 867 {
 868         if (!console_subchannel_in_use)
 869                 return NULL;
 870         return &console_subchannel;
 871 }
 872
 873 const char *cio_get_console_sch_name(struct subchannel_id schid)
 874 {
 875         snprintf(console_sch_name, 10, "0.%x.%04x", schid.ssid, schid.sch_no);
 876         return (const char *)console_sch_name;
 877 }
 878
 879 #endif
 880 static int
 881 __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
 882 {
 883         int retry, cc;
 884
 885         cc = 0;
 886         for (retry=0;retry<3;retry++) {
 887                 schib->pmcw.ena = 0;
 888                 cc = msch(schid, schib);
 889                 if (cc)
 890                         return (cc==3?-ENODEV:-EBUSY);
 891                 if (stsch(schid, schib) || !css_sch_is_valid(schib))
 892                         return -ENODEV;
 893                 if (!schib->pmcw.ena)
 894                         return 0;
 895         }
 896         return -EBUSY; /* uhm... */
 897 }
 898
 899 static int
 900 __clear_io_subchannel_easy(struct subchannel_id schid)
 901 {
 902         int retry;
 903
 904         if (csch(schid))
 905                 return -ENODEV;
 906         for (retry=0;retry<20;retry++) {
 907                 struct tpi_info ti;
 908
 909                 if (tpi(&ti)) {
 910                         tsch(ti.schid, (struct irb *)__LC_IRB);
 911                         if (schid_equal(&ti.schid, &schid))
 912                                 return 0;
 913                 }
 914                 udelay_simple(100);
 915         }
 916         return -EBUSY;
 917 }
 918
 919 static void __clear_chsc_subchannel_easy(void)
 920 {
 921         /* It seems we can only wait for a bit here :/ */
 922         udelay_simple(100);
 923 }
 924
 925 static int pgm_check_occured;
 926
 927 static void cio_reset_pgm_check_handler(void)
 928 {
 929         pgm_check_occured = 1;
 930 }
 931
 932 static int stsch_reset(struct subchannel_id schid, struct schib *addr)
 933 {
 934         int rc;
 935
 936         pgm_check_occured = 0;
 937         s390_base_pgm_handler_fn = cio_reset_pgm_check_handler;
 938         rc = stsch(schid, addr);
 939         s390_base_pgm_handler_fn = NULL;
 940
 941         /* The program check handler could have changed pgm_check_occured. */
 942         barrier();
 943
 944         if (pgm_check_occured)
 945                 return -EIO;
 946         else
 947                 return rc;
 948 }
 949
 950 static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
 951 {
 952         struct schib schib;
 953
 954         if (stsch_reset(schid, &schib))
 955                 return -ENXIO;
 956         if (!schib.pmcw.ena)
 957                 return 0;
 958         switch(__disable_subchannel_easy(schid, &schib)) {
 959         case 0:
 960         case -ENODEV:
 961                 break;
 962         default: /* -EBUSY */
 963                 switch (schib.pmcw.st) {
 964                 case SUBCHANNEL_TYPE_IO:
 965                         if (__clear_io_subchannel_easy(schid))
 966                                 goto out; /* give up... */
 967                         break;
 968                 case SUBCHANNEL_TYPE_CHSC:
 969                         __clear_chsc_subchannel_easy();
 970                         break;
 971                 default:
 972                         /* No default clear strategy */
 973                         break;
 974                 }
 975                 stsch(schid, &schib);
 976                 __disable_subchannel_easy(schid, &schib);
 977         }
 978 out:
 979         return 0;
 980 }
 981
 982 static atomic_t chpid_reset_count;
 983
 984 static void s390_reset_chpids_mcck_handler(void)
 985 {
 986         struct crw crw;
 987         struct mci *mci;
 988
 989         /* Check for pending channel report word. */
 990         mci = (struct mci *)&S390_lowcore.mcck_interruption_code;
 991         if (!mci->cp)
 992                 return;
 993         /* Process channel report words. */
 994         while (stcrw(&crw) == 0) {
 995                 /* Check for responses to RCHP. */
 996                 if (crw.slct && crw.rsc == CRW_RSC_CPATH)
 997                         atomic_dec(&chpid_reset_count);
 998         }
 999 }
1000
1001 #define RCHP_TIMEOUT (30 * USEC_PER_SEC)
1002 static void css_reset(void)
1003 {
1004         int i, ret;
1005         unsigned long long timeout;
1006         struct chp_id chpid;
1007
1008         /* Reset subchannels. */
1009         for_each_subchannel(__shutdown_subchannel_easy,  NULL);
1010         /* Reset channel paths. */
1011         s390_base_mcck_handler_fn = s390_reset_chpids_mcck_handler;
1012         /* Enable channel report machine checks. */
1013         __ctl_set_bit(14, 28);
1014         /* Temporarily reenable machine checks. */
1015         local_mcck_enable();
1016         chp_id_init(&chpid);
1017         for (i = 0; i <= __MAX_CHPID; i++) {
1018                 chpid.id = i;
1019                 ret = rchp(chpid);
1020                 if ((ret == 0) || (ret == 2))
1021                         /*
1022                          * rchp either succeeded, or another rchp is already
1023                          * in progress. In either case, we'll get a crw.
1024                          */
1025                         atomic_inc(&chpid_reset_count);
1026         }
1027         /* Wait for machine check for all channel paths. */
1028         timeout = get_clock() + (RCHP_TIMEOUT << 12);
1029         while (atomic_read(&chpid_reset_count) != 0) {
1030                 if (get_clock() > timeout)
1031                         break;
1032                 cpu_relax();
1033         }
1034         /* Disable machine checks again. */
1035         local_mcck_disable();
1036         /* Disable channel report machine checks. */
1037         __ctl_clear_bit(14, 28);
1038         s390_base_mcck_handler_fn = NULL;
1039 }
1040
1041 static struct reset_call css_reset_call = {
1042         .fn = css_reset,
1043 };
1044
1045 static int __init init_css_reset_call(void)
1046 {
1047         atomic_set(&chpid_reset_count, 0);
1048         register_reset_call(&css_reset_call);
1049         return 0;
1050 }
1051
1052 arch_initcall(init_css_reset_call);
1053
1054 struct sch_match_id {
1055         struct subchannel_id schid;
1056         struct ccw_dev_id devid;
1057         int rc;
1058 };
1059
1060 static int __reipl_subchannel_match(struct subchannel_id schid, void *data)
1061 {
1062         struct schib schib;
1063         struct sch_match_id *match_id = data;
1064
1065         if (stsch_reset(schid, &schib))
1066                 return -ENXIO;
1067         if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv &&
1068             (schib.pmcw.dev == match_id->devid.devno) &&
1069             (schid.ssid == match_id->devid.ssid)) {
1070                 match_id->schid = schid;
1071                 match_id->rc = 0;
1072                 return 1;
1073         }
1074         return 0;
1075 }
1076
1077 static int reipl_find_schid(struct ccw_dev_id *devid,
1078                             struct subchannel_id *schid)
1079 {
1080         struct sch_match_id match_id;
1081
1082         match_id.devid = *devid;
1083         match_id.rc = -ENODEV;
1084         for_each_subchannel(__reipl_subchannel_match, &match_id);
1085         if (match_id.rc == 0)
1086                 *schid = match_id.schid;
1087         return match_id.rc;
1088 }
1089
1090 extern void do_reipl_asm(__u32 schid);
1091
1092 /* Make sure all subchannels are quiet before we re-ipl an lpar. */
1093 void reipl_ccw_dev(struct ccw_dev_id *devid)
1094 {
1095         struct subchannel_id schid;
1096
1097         s390_reset_system();
1098         if (reipl_find_schid(devid, &schid) != 0)
1099                 panic("IPL Device not found\n");
1100         do_reipl_asm(*((__u32*)&schid));
1101 }
1102
1103 int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo)
1104 {
1105         struct subchannel_id schid;
1106         struct schib schib;
1107
1108         schid = *(struct subchannel_id *)__LC_SUBCHANNEL_ID;
1109         if (!schid.one)
1110                 return -ENODEV;
1111         if (stsch(schid, &schib))
1112                 return -ENODEV;
1113         if (schib.pmcw.st != SUBCHANNEL_TYPE_IO)
1114                 return -ENODEV;
1115         if (!schib.pmcw.dnv)
1116                 return -ENODEV;
1117         iplinfo->devno = schib.pmcw.dev;
1118         iplinfo->is_qdio = schib.pmcw.qf;
1119         return 0;
1120 }
1121
1122 /**
1123  * cio_tm_start_key - perform start function
1124  * @sch: subchannel on which to perform the start function
1125  * @tcw: transport-command word to be started
1126  * @lpm: mask of paths to use
1127  * @key: storage key to use for storage access
1128  *
1129  * Start the tcw on the given subchannel. Return zero on success, non-zero
1130  * otherwise.
1131  */
1132 int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key)
1133 {
1134         int cc;
1135         union orb *orb = &to_io_private(sch)->orb;
1136
1137         memset(orb, 0, sizeof(union orb));
1138         orb->tm.intparm = (u32) (addr_t) sch;
1139         orb->tm.key = key >> 4;
1140         orb->tm.b = 1;
1141         orb->tm.lpm = lpm ? lpm : sch->lpm;
1142         orb->tm.tcw = (u32) (addr_t) tcw;
1143         cc = ssch(sch->schid, orb);
1144         switch (cc) {
1145         case 0:
1146                 return 0;
1147         case 1:
1148         case 2:
1149                 return -EBUSY;
1150         default:
1151                 return cio_start_handle_notoper(sch, lpm);
1152         }
1153 }
1154
1155 /**
1156  * cio_tm_intrg - perform interrogate function
1157  * @sch - subchannel on which to perform the interrogate function
1158  *
1159  * If the specified subchannel is running in transport-mode, perform the
1160  * interrogate function. Return zero on success, non-zero otherwie.
1161  */
1162 int cio_tm_intrg(struct subchannel *sch)
1163 {
1164         int cc;
1165
1166         if (!to_io_private(sch)->orb.tm.b)
1167                 return -EINVAL;
1168         cc = xsch(sch->schid);
1169         switch (cc) {
1170         case 0:
1171         case 2:
1172                 return 0;
1173         case 1:
1174                 return -EBUSY;
1175         default:
1176                 return -ENODEV;
1177         }
1178 }