1 /* 2 * S/390 common I/O routines -- low level i/o calls 3 * 4 * Copyright IBM Corp. 1999, 2008 5 * Author(s): Ingo Adlung (adlung@de.ibm.com) 6 * Cornelia Huck (cornelia.huck@de.ibm.com) 7 * Arnd Bergmann (arndb@de.ibm.com) 8 * Martin Schwidefsky (schwidefsky@de.ibm.com) 9 */ 10 11 #define KMSG_COMPONENT "cio" 12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 13 14 #include <linux/ftrace.h> 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/cputime.h> 32 #include <asm/fcx.h> 33 #include <asm/nmi.h> 34 #include <asm/crw.h> 35 #include "cio.h" 36 #include "css.h" 37 #include "chsc.h" 38 #include "ioasm.h" 39 #include "io_sch.h" 40 #include "blacklist.h" 41 #include "cio_debug.h" 42 #include "chp.h" 43 44 debug_info_t *cio_debug_msg_id; 45 debug_info_t *cio_debug_trace_id; 46 debug_info_t *cio_debug_crw_id; 47 48 /* 49 * Function: cio_debug_init 50 * Initializes three debug logs for common I/O: 51 * - cio_msg logs generic cio messages 52 * - cio_trace logs the calling of different functions 53 * - cio_crw logs machine check related cio messages 54 */ 55 static int __init cio_debug_init(void) 56 { 57 cio_debug_msg_id = debug_register("cio_msg", 16, 1, 16 * sizeof(long)); 58 if (!cio_debug_msg_id) 59 goto out_unregister; 60 debug_register_view(cio_debug_msg_id, &debug_sprintf_view); 61 debug_set_level(cio_debug_msg_id, 2); 62 cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16); 63 if (!cio_debug_trace_id) 64 goto out_unregister; 65 debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view); 66 debug_set_level(cio_debug_trace_id, 2); 67 cio_debug_crw_id = debug_register("cio_crw", 16, 1, 16 * sizeof(long)); 68 if (!cio_debug_crw_id) 69 goto out_unregister; 70 debug_register_view(cio_debug_crw_id, &debug_sprintf_view); 71 debug_set_level(cio_debug_crw_id, 4); 72 return 0; 73 74 out_unregister: 75 if (cio_debug_msg_id) 76 debug_unregister(cio_debug_msg_id); 77 if (cio_debug_trace_id) 78 debug_unregister(cio_debug_trace_id); 79 if (cio_debug_crw_id) 80 debug_unregister(cio_debug_crw_id); 81 return -1; 82 } 83 84 arch_initcall (cio_debug_init); 85 86 int cio_set_options(struct subchannel *sch, int flags) 87 { 88 struct io_subchannel_private *priv = to_io_private(sch); 89 90 priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0; 91 priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0; 92 priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0; 93 return 0; 94 } 95 96 static int 97 cio_start_handle_notoper(struct subchannel *sch, __u8 lpm) 98 { 99 char dbf_text[15]; 100 101 if (lpm != 0) 102 sch->lpm &= ~lpm; 103 else 104 sch->lpm = 0; 105 106 CIO_MSG_EVENT(2, "cio_start: 'not oper' status for " 107 "subchannel 0.%x.%04x!\n", sch->schid.ssid, 108 sch->schid.sch_no); 109 110 if (cio_update_schib(sch)) 111 return -ENODEV; 112 113 sprintf(dbf_text, "no%s", dev_name(&sch->dev)); 114 CIO_TRACE_EVENT(0, dbf_text); 115 CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib)); 116 117 return (sch->lpm ? -EACCES : -ENODEV); 118 } 119 120 int 121 cio_start_key (struct subchannel *sch, /* subchannel structure */ 122 struct ccw1 * cpa, /* logical channel prog addr */ 123 __u8 lpm, /* logical path mask */ 124 __u8 key) /* storage key */ 125 { 126 struct io_subchannel_private *priv = to_io_private(sch); 127 union orb *orb = &priv->orb; 128 int ccode; 129 130 CIO_TRACE_EVENT(5, "stIO"); 131 CIO_TRACE_EVENT(5, dev_name(&sch->dev)); 132 133 memset(orb, 0, sizeof(union orb)); 134 /* sch is always under 2G. */ 135 orb->cmd.intparm = (u32)(addr_t)sch; 136 orb->cmd.fmt = 1; 137 138 orb->cmd.pfch = priv->options.prefetch == 0; 139 orb->cmd.spnd = priv->options.suspend; 140 orb->cmd.ssic = priv->options.suspend && priv->options.inter; 141 orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm; 142 #ifdef CONFIG_64BIT 143 /* 144 * for 64 bit we always support 64 bit IDAWs with 4k page size only 145 */ 146 orb->cmd.c64 = 1; 147 orb->cmd.i2k = 0; 148 #endif 149 orb->cmd.key = key >> 4; 150 /* issue "Start Subchannel" */ 151 orb->cmd.cpa = (__u32) __pa(cpa); 152 ccode = ssch(sch->schid, orb); 153 154 /* process condition code */ 155 CIO_HEX_EVENT(5, &ccode, sizeof(ccode)); 156 157 switch (ccode) { 158 case 0: 159 /* 160 * initialize device status information 161 */ 162 sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND; 163 return 0; 164 case 1: /* status pending */ 165 case 2: /* busy */ 166 return -EBUSY; 167 case 3: /* device/path not operational */ 168 return cio_start_handle_notoper(sch, lpm); 169 default: 170 return ccode; 171 } 172 } 173 174 int 175 cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm) 176 { 177 return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY); 178 } 179 180 /* 181 * resume suspended I/O operation 182 */ 183 int 184 cio_resume (struct subchannel *sch) 185 { 186 int ccode; 187 188 CIO_TRACE_EVENT(4, "resIO"); 189 CIO_TRACE_EVENT(4, dev_name(&sch->dev)); 190 191 ccode = rsch (sch->schid); 192 193 CIO_HEX_EVENT(4, &ccode, sizeof(ccode)); 194 195 switch (ccode) { 196 case 0: 197 sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND; 198 return 0; 199 case 1: 200 return -EBUSY; 201 case 2: 202 return -EINVAL; 203 default: 204 /* 205 * useless to wait for request completion 206 * as device is no longer operational ! 207 */ 208 return -ENODEV; 209 } 210 } 211 212 /* 213 * halt I/O operation 214 */ 215 int 216 cio_halt(struct subchannel *sch) 217 { 218 int ccode; 219 220 if (!sch) 221 return -ENODEV; 222 223 CIO_TRACE_EVENT(2, "haltIO"); 224 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 225 226 /* 227 * Issue "Halt subchannel" and process condition code 228 */ 229 ccode = hsch (sch->schid); 230 231 CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); 232 233 switch (ccode) { 234 case 0: 235 sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND; 236 return 0; 237 case 1: /* status pending */ 238 case 2: /* busy */ 239 return -EBUSY; 240 default: /* device not operational */ 241 return -ENODEV; 242 } 243 } 244 245 /* 246 * Clear I/O operation 247 */ 248 int 249 cio_clear(struct subchannel *sch) 250 { 251 int ccode; 252 253 if (!sch) 254 return -ENODEV; 255 256 CIO_TRACE_EVENT(2, "clearIO"); 257 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 258 259 /* 260 * Issue "Clear subchannel" and process condition code 261 */ 262 ccode = csch (sch->schid); 263 264 CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); 265 266 switch (ccode) { 267 case 0: 268 sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND; 269 return 0; 270 default: /* device not operational */ 271 return -ENODEV; 272 } 273 } 274 275 /* 276 * Function: cio_cancel 277 * Issues a "Cancel Subchannel" on the specified subchannel 278 * Note: We don't need any fancy intparms and flags here 279 * since xsch is executed synchronously. 280 * Only for common I/O internal use as for now. 281 */ 282 int 283 cio_cancel (struct subchannel *sch) 284 { 285 int ccode; 286 287 if (!sch) 288 return -ENODEV; 289 290 CIO_TRACE_EVENT(2, "cancelIO"); 291 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 292 293 ccode = xsch (sch->schid); 294 295 CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); 296 297 switch (ccode) { 298 case 0: /* success */ 299 /* Update information in scsw. */ 300 if (cio_update_schib(sch)) 301 return -ENODEV; 302 return 0; 303 case 1: /* status pending */ 304 return -EBUSY; 305 case 2: /* not applicable */ 306 return -EINVAL; 307 default: /* not oper */ 308 return -ENODEV; 309 } 310 } 311 312 313 static void cio_apply_config(struct subchannel *sch, struct schib *schib) 314 { 315 schib->pmcw.intparm = sch->config.intparm; 316 schib->pmcw.mbi = sch->config.mbi; 317 schib->pmcw.isc = sch->config.isc; 318 schib->pmcw.ena = sch->config.ena; 319 schib->pmcw.mme = sch->config.mme; 320 schib->pmcw.mp = sch->config.mp; 321 schib->pmcw.csense = sch->config.csense; 322 schib->pmcw.mbfc = sch->config.mbfc; 323 if (sch->config.mbfc) 324 schib->mba = sch->config.mba; 325 } 326 327 static int cio_check_config(struct subchannel *sch, struct schib *schib) 328 { 329 return (schib->pmcw.intparm == sch->config.intparm) && 330 (schib->pmcw.mbi == sch->config.mbi) && 331 (schib->pmcw.isc == sch->config.isc) && 332 (schib->pmcw.ena == sch->config.ena) && 333 (schib->pmcw.mme == sch->config.mme) && 334 (schib->pmcw.mp == sch->config.mp) && 335 (schib->pmcw.csense == sch->config.csense) && 336 (schib->pmcw.mbfc == sch->config.mbfc) && 337 (!sch->config.mbfc || (schib->mba == sch->config.mba)); 338 } 339 340 /* 341 * cio_commit_config - apply configuration to the subchannel 342 */ 343 int cio_commit_config(struct subchannel *sch) 344 { 345 int ccode, retry, ret = 0; 346 struct schib schib; 347 struct irb irb; 348 349 if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib)) 350 return -ENODEV; 351 352 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; 367 } 368 ret = -EAGAIN; 369 break; 370 case 1: /* status pending */ 371 ret = -EBUSY; 372 if (tsch(sch->schid, &irb)) 373 return ret; 374 break; 375 case 2: /* busy */ 376 udelay(100); /* allow for recovery */ 377 ret = -EBUSY; 378 break; 379 case 3: /* not operational */ 380 return -ENODEV; 381 } 382 } 383 return ret; 384 } 385 386 /** 387 * cio_update_schib - Perform stsch and update schib if subchannel is valid. 388 * @sch: subchannel on which to perform stsch 389 * Return zero on success, -ENODEV otherwise. 390 */ 391 int cio_update_schib(struct subchannel *sch) 392 { 393 struct schib schib; 394 395 if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib)) 396 return -ENODEV; 397 398 memcpy(&sch->schib, &schib, sizeof(schib)); 399 return 0; 400 } 401 EXPORT_SYMBOL_GPL(cio_update_schib); 402 403 /** 404 * cio_enable_subchannel - enable a subchannel. 405 * @sch: subchannel to be enabled 406 * @intparm: interruption parameter to set 407 */ 408 int cio_enable_subchannel(struct subchannel *sch, u32 intparm) 409 { 410 int ret; 411 412 CIO_TRACE_EVENT(2, "ensch"); 413 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 414 415 if (sch_is_pseudo_sch(sch)) 416 return -EINVAL; 417 if (cio_update_schib(sch)) 418 return -ENODEV; 419 420 sch->config.ena = 1; 421 sch->config.isc = sch->isc; 422 sch->config.intparm = intparm; 423 424 ret = cio_commit_config(sch); 425 if (ret == -EIO) { 426 /* 427 * Got a program check in msch. Try without 428 * the concurrent sense bit the next time. 429 */ 430 sch->config.csense = 0; 431 ret = cio_commit_config(sch); 432 } 433 CIO_HEX_EVENT(2, &ret, sizeof(ret)); 434 return ret; 435 } 436 EXPORT_SYMBOL_GPL(cio_enable_subchannel); 437 438 /** 439 * cio_disable_subchannel - disable a subchannel. 440 * @sch: subchannel to disable 441 */ 442 int cio_disable_subchannel(struct subchannel *sch) 443 { 444 int ret; 445 446 CIO_TRACE_EVENT(2, "dissch"); 447 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 448 449 if (sch_is_pseudo_sch(sch)) 450 return 0; 451 if (cio_update_schib(sch)) 452 return -ENODEV; 453 454 sch->config.ena = 0; 455 ret = cio_commit_config(sch); 456 457 CIO_HEX_EVENT(2, &ret, sizeof(ret)); 458 return ret; 459 } 460 EXPORT_SYMBOL_GPL(cio_disable_subchannel); 461 462 static int cio_check_devno_blacklisted(struct subchannel *sch) 463 { 464 if (is_blacklisted(sch->schid.ssid, sch->schib.pmcw.dev)) { 465 /* 466 * This device must not be known to Linux. So we simply 467 * say that there is no device and return ENODEV. 468 */ 469 CIO_MSG_EVENT(6, "Blacklisted device detected " 470 "at devno %04X, subchannel set %x\n", 471 sch->schib.pmcw.dev, sch->schid.ssid); 472 return -ENODEV; 473 } 474 return 0; 475 } 476 477 static int cio_validate_io_subchannel(struct subchannel *sch) 478 { 479 /* Initialization for io subchannels. */ 480 if (!css_sch_is_valid(&sch->schib)) 481 return -ENODEV; 482 483 /* Devno is valid. */ 484 return cio_check_devno_blacklisted(sch); 485 } 486 487 static int cio_validate_msg_subchannel(struct subchannel *sch) 488 { 489 /* Initialization for message subchannels. */ 490 if (!css_sch_is_valid(&sch->schib)) 491 return -ENODEV; 492 493 /* Devno is valid. */ 494 return cio_check_devno_blacklisted(sch); 495 } 496 497 /** 498 * cio_validate_subchannel - basic validation of subchannel 499 * @sch: subchannel structure to be filled out 500 * @schid: subchannel id 501 * 502 * Find out subchannel type and initialize struct subchannel. 503 * Return codes: 504 * 0 on success 505 * -ENXIO for non-defined subchannels 506 * -ENODEV for invalid subchannels or blacklisted devices 507 * -EIO for subchannels in an invalid subchannel set 508 */ 509 int cio_validate_subchannel(struct subchannel *sch, struct subchannel_id schid) 510 { 511 char dbf_txt[15]; 512 int ccode; 513 int err; 514 515 sprintf(dbf_txt, "valsch%x", schid.sch_no); 516 CIO_TRACE_EVENT(4, dbf_txt); 517 518 /* 519 * The first subchannel that is not-operational (ccode==3) 520 * indicates that there aren't any more devices available. 521 * If stsch gets an exception, it means the current subchannel set 522 * is not valid. 523 */ 524 ccode = stsch_err(schid, &sch->schib); 525 if (ccode) { 526 err = (ccode == 3) ? -ENXIO : ccode; 527 goto out; 528 } 529 sch->st = sch->schib.pmcw.st; 530 sch->schid = schid; 531 532 switch (sch->st) { 533 case SUBCHANNEL_TYPE_IO: 534 err = cio_validate_io_subchannel(sch); 535 break; 536 case SUBCHANNEL_TYPE_MSG: 537 err = cio_validate_msg_subchannel(sch); 538 break; 539 default: 540 err = 0; 541 } 542 if (err) 543 goto out; 544 545 CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n", 546 sch->schid.ssid, sch->schid.sch_no, sch->st); 547 out: 548 return err; 549 } 550 551 /* 552 * do_cio_interrupt() handles all normal I/O device IRQ's 553 */ 554 static irqreturn_t do_cio_interrupt(int irq, void *dummy) 555 { 556 struct tpi_info *tpi_info; 557 struct subchannel *sch; 558 struct irb *irb; 559 560 __this_cpu_write(s390_idle.nohz_delay, 1); 561 tpi_info = (struct tpi_info *) &get_irq_regs()->int_code; 562 irb = (struct irb *) &S390_lowcore.irb; 563 sch = (struct subchannel *)(unsigned long) tpi_info->intparm; 564 if (!sch) { 565 /* Clear pending interrupt condition. */ 566 inc_irq_stat(IRQIO_CIO); 567 tsch(tpi_info->schid, irb); 568 return IRQ_HANDLED; 569 } 570 spin_lock(sch->lock); 571 /* Store interrupt response block to lowcore. */ 572 if (tsch(tpi_info->schid, irb) == 0) { 573 /* Keep subchannel information word up to date. */ 574 memcpy (&sch->schib.scsw, &irb->scsw, sizeof (irb->scsw)); 575 /* Call interrupt handler if there is one. */ 576 if (sch->driver && sch->driver->irq) 577 sch->driver->irq(sch); 578 else 579 inc_irq_stat(IRQIO_CIO); 580 } else 581 inc_irq_stat(IRQIO_CIO); 582 spin_unlock(sch->lock); 583 584 return IRQ_HANDLED; 585 } 586 587 static struct irq_desc *irq_desc_io; 588 589 static struct irqaction io_interrupt = { 590 .name = "IO", 591 .handler = do_cio_interrupt, 592 }; 593 594 void __init init_cio_interrupts(void) 595 { 596 irq_set_chip_and_handler(IO_INTERRUPT, 597 &dummy_irq_chip, handle_percpu_irq); 598 setup_irq(IO_INTERRUPT, &io_interrupt); 599 irq_desc_io = irq_to_desc(IO_INTERRUPT); 600 } 601 602 #ifdef CONFIG_CCW_CONSOLE 603 static struct subchannel *console_sch; 604 605 /* 606 * Use cio_tsch to update the subchannel status and call the interrupt handler 607 * if status had been pending. Called with the subchannel's lock held. 608 */ 609 void cio_tsch(struct subchannel *sch) 610 { 611 struct irb *irb; 612 int irq_context; 613 614 irb = (struct irb *)&S390_lowcore.irb; 615 /* Store interrupt response block to lowcore. */ 616 if (tsch(sch->schid, irb) != 0) 617 /* Not status pending or not operational. */ 618 return; 619 memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw)); 620 /* Call interrupt handler with updated status. */ 621 irq_context = in_interrupt(); 622 if (!irq_context) { 623 local_bh_disable(); 624 irq_enter(); 625 } 626 kstat_incr_irqs_this_cpu(IO_INTERRUPT, irq_desc_io); 627 if (sch->driver && sch->driver->irq) 628 sch->driver->irq(sch); 629 else 630 inc_irq_stat(IRQIO_CIO); 631 if (!irq_context) { 632 irq_exit(); 633 _local_bh_enable(); 634 } 635 } 636 637 static int cio_test_for_console(struct subchannel_id schid, void *data) 638 { 639 struct schib schib; 640 641 if (stsch_err(schid, &schib) != 0) 642 return -ENXIO; 643 if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv && 644 (schib.pmcw.dev == console_devno)) { 645 console_irq = schid.sch_no; 646 return 1; /* found */ 647 } 648 return 0; 649 } 650 651 static int cio_get_console_sch_no(void) 652 { 653 struct subchannel_id schid; 654 struct schib schib; 655 656 init_subchannel_id(&schid); 657 if (console_irq != -1) { 658 /* VM provided us with the irq number of the console. */ 659 schid.sch_no = console_irq; 660 if (stsch_err(schid, &schib) != 0 || 661 (schib.pmcw.st != SUBCHANNEL_TYPE_IO) || !schib.pmcw.dnv) 662 return -1; 663 console_devno = schib.pmcw.dev; 664 } else if (console_devno != -1) { 665 /* At least the console device number is known. */ 666 for_each_subchannel(cio_test_for_console, NULL); 667 } 668 return console_irq; 669 } 670 671 struct subchannel *cio_probe_console(void) 672 { 673 struct subchannel_id schid; 674 struct subchannel *sch; 675 int sch_no, ret; 676 677 sch_no = cio_get_console_sch_no(); 678 if (sch_no == -1) { 679 pr_warning("No CCW console was found\n"); 680 return ERR_PTR(-ENODEV); 681 } 682 init_subchannel_id(&schid); 683 schid.sch_no = sch_no; 684 sch = css_alloc_subchannel(schid); 685 if (IS_ERR(sch)) 686 return sch; 687 688 isc_register(CONSOLE_ISC); 689 sch->config.isc = CONSOLE_ISC; 690 sch->config.intparm = (u32)(addr_t)sch; 691 ret = cio_commit_config(sch); 692 if (ret) { 693 isc_unregister(CONSOLE_ISC); 694 put_device(&sch->dev); 695 return ERR_PTR(ret); 696 } 697 console_sch = sch; 698 return sch; 699 } 700 701 int cio_is_console(struct subchannel_id schid) 702 { 703 if (!console_sch) 704 return 0; 705 return schid_equal(&schid, &console_sch->schid); 706 } 707 708 void cio_register_early_subchannels(void) 709 { 710 int ret; 711 712 if (!console_sch) 713 return; 714 715 ret = css_register_subchannel(console_sch); 716 if (ret) 717 put_device(&console_sch->dev); 718 } 719 #endif /* CONFIG_CCW_CONSOLE */ 720 721 static int 722 __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib) 723 { 724 int retry, cc; 725 726 cc = 0; 727 for (retry=0;retry<3;retry++) { 728 schib->pmcw.ena = 0; 729 cc = msch_err(schid, schib); 730 if (cc) 731 return (cc==3?-ENODEV:-EBUSY); 732 if (stsch_err(schid, schib) || !css_sch_is_valid(schib)) 733 return -ENODEV; 734 if (!schib->pmcw.ena) 735 return 0; 736 } 737 return -EBUSY; /* uhm... */ 738 } 739 740 static int 741 __clear_io_subchannel_easy(struct subchannel_id schid) 742 { 743 int retry; 744 745 if (csch(schid)) 746 return -ENODEV; 747 for (retry=0;retry<20;retry++) { 748 struct tpi_info ti; 749 750 if (tpi(&ti)) { 751 tsch(ti.schid, (struct irb *)&S390_lowcore.irb); 752 if (schid_equal(&ti.schid, &schid)) 753 return 0; 754 } 755 udelay_simple(100); 756 } 757 return -EBUSY; 758 } 759 760 static void __clear_chsc_subchannel_easy(void) 761 { 762 /* It seems we can only wait for a bit here :/ */ 763 udelay_simple(100); 764 } 765 766 static int pgm_check_occured; 767 768 static void cio_reset_pgm_check_handler(void) 769 { 770 pgm_check_occured = 1; 771 } 772 773 static int stsch_reset(struct subchannel_id schid, struct schib *addr) 774 { 775 int rc; 776 777 pgm_check_occured = 0; 778 s390_base_pgm_handler_fn = cio_reset_pgm_check_handler; 779 rc = stsch_err(schid, addr); 780 s390_base_pgm_handler_fn = NULL; 781 782 /* The program check handler could have changed pgm_check_occured. */ 783 barrier(); 784 785 if (pgm_check_occured) 786 return -EIO; 787 else 788 return rc; 789 } 790 791 static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data) 792 { 793 struct schib schib; 794 795 if (stsch_reset(schid, &schib)) 796 return -ENXIO; 797 if (!schib.pmcw.ena) 798 return 0; 799 switch(__disable_subchannel_easy(schid, &schib)) { 800 case 0: 801 case -ENODEV: 802 break; 803 default: /* -EBUSY */ 804 switch (schib.pmcw.st) { 805 case SUBCHANNEL_TYPE_IO: 806 if (__clear_io_subchannel_easy(schid)) 807 goto out; /* give up... */ 808 break; 809 case SUBCHANNEL_TYPE_CHSC: 810 __clear_chsc_subchannel_easy(); 811 break; 812 default: 813 /* No default clear strategy */ 814 break; 815 } 816 stsch_err(schid, &schib); 817 __disable_subchannel_easy(schid, &schib); 818 } 819 out: 820 return 0; 821 } 822 823 static atomic_t chpid_reset_count; 824 825 static void s390_reset_chpids_mcck_handler(void) 826 { 827 struct crw crw; 828 struct mci *mci; 829 830 /* Check for pending channel report word. */ 831 mci = (struct mci *)&S390_lowcore.mcck_interruption_code; 832 if (!mci->cp) 833 return; 834 /* Process channel report words. */ 835 while (stcrw(&crw) == 0) { 836 /* Check for responses to RCHP. */ 837 if (crw.slct && crw.rsc == CRW_RSC_CPATH) 838 atomic_dec(&chpid_reset_count); 839 } 840 } 841 842 #define RCHP_TIMEOUT (30 * USEC_PER_SEC) 843 static void css_reset(void) 844 { 845 int i, ret; 846 unsigned long long timeout; 847 struct chp_id chpid; 848 849 /* Reset subchannels. */ 850 for_each_subchannel(__shutdown_subchannel_easy, NULL); 851 /* Reset channel paths. */ 852 s390_base_mcck_handler_fn = s390_reset_chpids_mcck_handler; 853 /* Enable channel report machine checks. */ 854 __ctl_set_bit(14, 28); 855 /* Temporarily reenable machine checks. */ 856 local_mcck_enable(); 857 chp_id_init(&chpid); 858 for (i = 0; i <= __MAX_CHPID; i++) { 859 chpid.id = i; 860 ret = rchp(chpid); 861 if ((ret == 0) || (ret == 2)) 862 /* 863 * rchp either succeeded, or another rchp is already 864 * in progress. In either case, we'll get a crw. 865 */ 866 atomic_inc(&chpid_reset_count); 867 } 868 /* Wait for machine check for all channel paths. */ 869 timeout = get_tod_clock_fast() + (RCHP_TIMEOUT << 12); 870 while (atomic_read(&chpid_reset_count) != 0) { 871 if (get_tod_clock_fast() > timeout) 872 break; 873 cpu_relax(); 874 } 875 /* Disable machine checks again. */ 876 local_mcck_disable(); 877 /* Disable channel report machine checks. */ 878 __ctl_clear_bit(14, 28); 879 s390_base_mcck_handler_fn = NULL; 880 } 881 882 static struct reset_call css_reset_call = { 883 .fn = css_reset, 884 }; 885 886 static int __init init_css_reset_call(void) 887 { 888 atomic_set(&chpid_reset_count, 0); 889 register_reset_call(&css_reset_call); 890 return 0; 891 } 892 893 arch_initcall(init_css_reset_call); 894 895 struct sch_match_id { 896 struct subchannel_id schid; 897 struct ccw_dev_id devid; 898 int rc; 899 }; 900 901 static int __reipl_subchannel_match(struct subchannel_id schid, void *data) 902 { 903 struct schib schib; 904 struct sch_match_id *match_id = data; 905 906 if (stsch_reset(schid, &schib)) 907 return -ENXIO; 908 if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv && 909 (schib.pmcw.dev == match_id->devid.devno) && 910 (schid.ssid == match_id->devid.ssid)) { 911 match_id->schid = schid; 912 match_id->rc = 0; 913 return 1; 914 } 915 return 0; 916 } 917 918 static int reipl_find_schid(struct ccw_dev_id *devid, 919 struct subchannel_id *schid) 920 { 921 struct sch_match_id match_id; 922 923 match_id.devid = *devid; 924 match_id.rc = -ENODEV; 925 for_each_subchannel(__reipl_subchannel_match, &match_id); 926 if (match_id.rc == 0) 927 *schid = match_id.schid; 928 return match_id.rc; 929 } 930 931 extern void do_reipl_asm(__u32 schid); 932 933 /* Make sure all subchannels are quiet before we re-ipl an lpar. */ 934 void reipl_ccw_dev(struct ccw_dev_id *devid) 935 { 936 struct subchannel_id uninitialized_var(schid); 937 938 s390_reset_system(NULL, NULL); 939 if (reipl_find_schid(devid, &schid) != 0) 940 panic("IPL Device not found\n"); 941 do_reipl_asm(*((__u32*)&schid)); 942 } 943 944 int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo) 945 { 946 struct subchannel_id schid; 947 struct schib schib; 948 949 schid = *(struct subchannel_id *)&S390_lowcore.subchannel_id; 950 if (!schid.one) 951 return -ENODEV; 952 if (stsch_err(schid, &schib)) 953 return -ENODEV; 954 if (schib.pmcw.st != SUBCHANNEL_TYPE_IO) 955 return -ENODEV; 956 if (!schib.pmcw.dnv) 957 return -ENODEV; 958 iplinfo->devno = schib.pmcw.dev; 959 iplinfo->is_qdio = schib.pmcw.qf; 960 return 0; 961 } 962 963 /** 964 * cio_tm_start_key - perform start function 965 * @sch: subchannel on which to perform the start function 966 * @tcw: transport-command word to be started 967 * @lpm: mask of paths to use 968 * @key: storage key to use for storage access 969 * 970 * Start the tcw on the given subchannel. Return zero on success, non-zero 971 * otherwise. 972 */ 973 int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key) 974 { 975 int cc; 976 union orb *orb = &to_io_private(sch)->orb; 977 978 memset(orb, 0, sizeof(union orb)); 979 orb->tm.intparm = (u32) (addr_t) sch; 980 orb->tm.key = key >> 4; 981 orb->tm.b = 1; 982 orb->tm.lpm = lpm ? lpm : sch->lpm; 983 orb->tm.tcw = (u32) (addr_t) tcw; 984 cc = ssch(sch->schid, orb); 985 switch (cc) { 986 case 0: 987 return 0; 988 case 1: 989 case 2: 990 return -EBUSY; 991 default: 992 return cio_start_handle_notoper(sch, lpm); 993 } 994 } 995 996 /** 997 * cio_tm_intrg - perform interrogate function 998 * @sch - subchannel on which to perform the interrogate function 999 * 1000 * If the specified subchannel is running in transport-mode, perform the 1001 * interrogate function. Return zero on success, non-zero otherwie. 1002 */ 1003 int cio_tm_intrg(struct subchannel *sch) 1004 { 1005 int cc; 1006 1007 if (!to_io_private(sch)->orb.tm.b) 1008 return -EINVAL; 1009 cc = xsch(sch->schid); 1010 switch (cc) { 1011 case 0: 1012 case 2: 1013 return 0; 1014 case 1: 1015 return -EBUSY; 1016 default: 1017 return -ENODEV; 1018 } 1019 } 1020