Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/x86/isa/atpic.c
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1 /*- 2 * Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 /* 28 * PIC driver for the 8259A Master and Slave PICs in PC/AT machines. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD: releng/10.4/sys/x86/isa/atpic.c 262192 2014-02-18 20:27:17Z jhb $"); 33 34 #include "opt_auto_eoi.h" 35 #include "opt_isa.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/bus.h> 40 #include <sys/interrupt.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/module.h> 44 45 #include <machine/cpufunc.h> 46 #include <machine/frame.h> 47 #include <machine/intr_machdep.h> 48 #include <machine/md_var.h> 49 #include <machine/resource.h> 50 #include <machine/segments.h> 51 52 #include <dev/ic/i8259.h> 53 #include <x86/isa/icu.h> 54 #ifdef PC98 55 #include <pc98/cbus/cbus.h> 56 #else 57 #include <x86/isa/isa.h> 58 #endif 59 #include <isa/isavar.h> 60 61 #ifdef __amd64__ 62 #define SDT_ATPIC SDT_SYSIGT 63 #define GSEL_ATPIC 0 64 #else 65 #define SDT_ATPIC SDT_SYS386IGT 66 #define GSEL_ATPIC GSEL(GCODE_SEL, SEL_KPL) 67 #endif 68 69 #define MASTER 0 70 #define SLAVE 1 71 72 #define NUM_ISA_IRQS 16 73 74 static void atpic_init(void *dummy); 75 76 unsigned int imen; /* XXX */ 77 78 inthand_t 79 IDTVEC(atpic_intr0), IDTVEC(atpic_intr1), IDTVEC(atpic_intr2), 80 IDTVEC(atpic_intr3), IDTVEC(atpic_intr4), IDTVEC(atpic_intr5), 81 IDTVEC(atpic_intr6), IDTVEC(atpic_intr7), IDTVEC(atpic_intr8), 82 IDTVEC(atpic_intr9), IDTVEC(atpic_intr10), IDTVEC(atpic_intr11), 83 IDTVEC(atpic_intr12), IDTVEC(atpic_intr13), IDTVEC(atpic_intr14), 84 IDTVEC(atpic_intr15); 85 86 #define IRQ(ap, ai) ((ap)->at_irqbase + (ai)->at_irq) 87 88 #define ATPIC(io, base, eoi, imenptr) \ 89 { { atpic_enable_source, atpic_disable_source, (eoi), \ 90 atpic_enable_intr, atpic_disable_intr, atpic_vector, \ 91 atpic_source_pending, NULL, atpic_resume, atpic_config_intr,\ 92 atpic_assign_cpu }, (io), (base), IDT_IO_INTS + (base), \ 93 (imenptr) } 94 95 #define INTSRC(irq) \ 96 { { &atpics[(irq) / 8].at_pic }, IDTVEC(atpic_intr ## irq ), \ 97 (irq) % 8 } 98 99 struct atpic { 100 struct pic at_pic; 101 int at_ioaddr; 102 int at_irqbase; 103 uint8_t at_intbase; 104 uint8_t *at_imen; 105 }; 106 107 struct atpic_intsrc { 108 struct intsrc at_intsrc; 109 inthand_t *at_intr; 110 int at_irq; /* Relative to PIC base. */ 111 enum intr_trigger at_trigger; 112 u_long at_count; 113 u_long at_straycount; 114 }; 115 116 static void atpic_enable_source(struct intsrc *isrc); 117 static void atpic_disable_source(struct intsrc *isrc, int eoi); 118 static void atpic_eoi_master(struct intsrc *isrc); 119 static void atpic_eoi_slave(struct intsrc *isrc); 120 static void atpic_enable_intr(struct intsrc *isrc); 121 static void atpic_disable_intr(struct intsrc *isrc); 122 static int atpic_vector(struct intsrc *isrc); 123 static void atpic_resume(struct pic *pic, bool suspend_cancelled); 124 static int atpic_source_pending(struct intsrc *isrc); 125 static int atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig, 126 enum intr_polarity pol); 127 static int atpic_assign_cpu(struct intsrc *isrc, u_int apic_id); 128 static void i8259_init(struct atpic *pic, int slave); 129 130 static struct atpic atpics[] = { 131 ATPIC(IO_ICU1, 0, atpic_eoi_master, (uint8_t *)&imen), 132 ATPIC(IO_ICU2, 8, atpic_eoi_slave, ((uint8_t *)&imen) + 1) 133 }; 134 135 static struct atpic_intsrc atintrs[] = { 136 INTSRC(0), 137 INTSRC(1), 138 INTSRC(2), 139 INTSRC(3), 140 INTSRC(4), 141 INTSRC(5), 142 INTSRC(6), 143 INTSRC(7), 144 INTSRC(8), 145 INTSRC(9), 146 INTSRC(10), 147 INTSRC(11), 148 INTSRC(12), 149 INTSRC(13), 150 INTSRC(14), 151 INTSRC(15), 152 }; 153 154 CTASSERT(sizeof(atintrs) / sizeof(atintrs[0]) == NUM_ISA_IRQS); 155 156 static __inline void 157 _atpic_eoi_master(struct intsrc *isrc) 158 { 159 160 KASSERT(isrc->is_pic == &atpics[MASTER].at_pic, 161 ("%s: mismatched pic", __func__)); 162 #ifndef AUTO_EOI_1 163 outb(atpics[MASTER].at_ioaddr, OCW2_EOI); 164 #endif 165 } 166 167 /* 168 * The data sheet says no auto-EOI on slave, but it sometimes works. 169 * So, if AUTO_EOI_2 is enabled, we use it. 170 */ 171 static __inline void 172 _atpic_eoi_slave(struct intsrc *isrc) 173 { 174 175 KASSERT(isrc->is_pic == &atpics[SLAVE].at_pic, 176 ("%s: mismatched pic", __func__)); 177 #ifndef AUTO_EOI_2 178 outb(atpics[SLAVE].at_ioaddr, OCW2_EOI); 179 #ifndef AUTO_EOI_1 180 outb(atpics[MASTER].at_ioaddr, OCW2_EOI); 181 #endif 182 #endif 183 } 184 185 static void 186 atpic_enable_source(struct intsrc *isrc) 187 { 188 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 189 struct atpic *ap = (struct atpic *)isrc->is_pic; 190 191 spinlock_enter(); 192 if (*ap->at_imen & IMEN_MASK(ai)) { 193 *ap->at_imen &= ~IMEN_MASK(ai); 194 outb(ap->at_ioaddr + ICU_IMR_OFFSET, *ap->at_imen); 195 } 196 spinlock_exit(); 197 } 198 199 static void 200 atpic_disable_source(struct intsrc *isrc, int eoi) 201 { 202 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 203 struct atpic *ap = (struct atpic *)isrc->is_pic; 204 205 spinlock_enter(); 206 if (ai->at_trigger != INTR_TRIGGER_EDGE) { 207 *ap->at_imen |= IMEN_MASK(ai); 208 outb(ap->at_ioaddr + ICU_IMR_OFFSET, *ap->at_imen); 209 } 210 211 /* 212 * Take care to call these functions directly instead of through 213 * a function pointer. All of the referenced variables should 214 * still be hot in the cache. 215 */ 216 if (eoi == PIC_EOI) { 217 if (isrc->is_pic == &atpics[MASTER].at_pic) 218 _atpic_eoi_master(isrc); 219 else 220 _atpic_eoi_slave(isrc); 221 } 222 223 spinlock_exit(); 224 } 225 226 static void 227 atpic_eoi_master(struct intsrc *isrc) 228 { 229 #ifndef AUTO_EOI_1 230 spinlock_enter(); 231 _atpic_eoi_master(isrc); 232 spinlock_exit(); 233 #endif 234 } 235 236 static void 237 atpic_eoi_slave(struct intsrc *isrc) 238 { 239 #ifndef AUTO_EOI_2 240 spinlock_enter(); 241 _atpic_eoi_slave(isrc); 242 spinlock_exit(); 243 #endif 244 } 245 246 static void 247 atpic_enable_intr(struct intsrc *isrc) 248 { 249 } 250 251 static void 252 atpic_disable_intr(struct intsrc *isrc) 253 { 254 } 255 256 257 static int 258 atpic_vector(struct intsrc *isrc) 259 { 260 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 261 struct atpic *ap = (struct atpic *)isrc->is_pic; 262 263 return (IRQ(ap, ai)); 264 } 265 266 static int 267 atpic_source_pending(struct intsrc *isrc) 268 { 269 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 270 struct atpic *ap = (struct atpic *)isrc->is_pic; 271 272 return (inb(ap->at_ioaddr) & IMEN_MASK(ai)); 273 } 274 275 static void 276 atpic_resume(struct pic *pic, bool suspend_cancelled) 277 { 278 struct atpic *ap = (struct atpic *)pic; 279 280 i8259_init(ap, ap == &atpics[SLAVE]); 281 #ifndef PC98 282 if (ap == &atpics[SLAVE] && elcr_found) 283 elcr_resume(); 284 #endif 285 } 286 287 static int 288 atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig, 289 enum intr_polarity pol) 290 { 291 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 292 u_int vector; 293 294 /* Map conforming values to edge/hi and sanity check the values. */ 295 if (trig == INTR_TRIGGER_CONFORM) 296 trig = INTR_TRIGGER_EDGE; 297 if (pol == INTR_POLARITY_CONFORM) 298 pol = INTR_POLARITY_HIGH; 299 vector = atpic_vector(isrc); 300 if ((trig == INTR_TRIGGER_EDGE && pol == INTR_POLARITY_LOW) || 301 (trig == INTR_TRIGGER_LEVEL && pol == INTR_POLARITY_HIGH)) { 302 printf( 303 "atpic: Mismatched config for IRQ%u: trigger %s, polarity %s\n", 304 vector, trig == INTR_TRIGGER_EDGE ? "edge" : "level", 305 pol == INTR_POLARITY_HIGH ? "high" : "low"); 306 return (EINVAL); 307 } 308 309 /* If there is no change, just return. */ 310 if (ai->at_trigger == trig) 311 return (0); 312 313 #ifdef PC98 314 if ((vector == 0 || vector == 1 || vector == 7 || vector == 8) && 315 trig == INTR_TRIGGER_LEVEL) { 316 if (bootverbose) 317 printf( 318 "atpic: Ignoring invalid level/low configuration for IRQ%u\n", 319 vector); 320 return (EINVAL); 321 } 322 return (ENXIO); 323 #else 324 /* 325 * Certain IRQs can never be level/lo, so don't try to set them 326 * that way if asked. At least some ELCR registers ignore setting 327 * these bits as well. 328 */ 329 if ((vector == 0 || vector == 1 || vector == 2 || vector == 13) && 330 trig == INTR_TRIGGER_LEVEL) { 331 if (bootverbose) 332 printf( 333 "atpic: Ignoring invalid level/low configuration for IRQ%u\n", 334 vector); 335 return (EINVAL); 336 } 337 if (!elcr_found) { 338 if (bootverbose) 339 printf("atpic: No ELCR to configure IRQ%u as %s\n", 340 vector, trig == INTR_TRIGGER_EDGE ? "edge/high" : 341 "level/low"); 342 return (ENXIO); 343 } 344 if (bootverbose) 345 printf("atpic: Programming IRQ%u as %s\n", vector, 346 trig == INTR_TRIGGER_EDGE ? "edge/high" : "level/low"); 347 spinlock_enter(); 348 elcr_write_trigger(atpic_vector(isrc), trig); 349 ai->at_trigger = trig; 350 spinlock_exit(); 351 return (0); 352 #endif /* PC98 */ 353 } 354 355 static int 356 atpic_assign_cpu(struct intsrc *isrc, u_int apic_id) 357 { 358 359 /* 360 * 8259A's are only used in UP in which case all interrupts always 361 * go to the sole CPU and this function shouldn't even be called. 362 */ 363 panic("%s: bad cookie", __func__); 364 } 365 366 static void 367 i8259_init(struct atpic *pic, int slave) 368 { 369 int imr_addr; 370 371 /* Reset the PIC and program with next four bytes. */ 372 spinlock_enter(); 373 #ifdef DEV_MCA 374 /* MCA uses level triggered interrupts. */ 375 if (MCA_system) 376 outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4 | ICW1_LTIM); 377 else 378 #endif 379 outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4); 380 imr_addr = pic->at_ioaddr + ICU_IMR_OFFSET; 381 382 /* Start vector. */ 383 outb(imr_addr, pic->at_intbase); 384 385 /* 386 * Setup slave links. For the master pic, indicate what line 387 * the slave is configured on. For the slave indicate 388 * which line on the master we are connected to. 389 */ 390 if (slave) 391 outb(imr_addr, ICU_SLAVEID); 392 else 393 outb(imr_addr, IRQ_MASK(ICU_SLAVEID)); 394 395 /* Set mode. */ 396 if (slave) 397 outb(imr_addr, SLAVE_MODE); 398 else 399 outb(imr_addr, MASTER_MODE); 400 401 /* Set interrupt enable mask. */ 402 outb(imr_addr, *pic->at_imen); 403 404 /* Reset is finished, default to IRR on read. */ 405 outb(pic->at_ioaddr, OCW3_SEL | OCW3_RR); 406 407 #ifndef PC98 408 /* OCW2_L1 sets priority order to 3-7, 0-2 (com2 first). */ 409 if (!slave) 410 outb(pic->at_ioaddr, OCW2_R | OCW2_SL | OCW2_L1); 411 #endif 412 spinlock_exit(); 413 } 414 415 void 416 atpic_startup(void) 417 { 418 struct atpic_intsrc *ai; 419 int i; 420 421 /* Start off with all interrupts disabled. */ 422 imen = 0xffff; 423 i8259_init(&atpics[MASTER], 0); 424 i8259_init(&atpics[SLAVE], 1); 425 atpic_enable_source((struct intsrc *)&atintrs[ICU_SLAVEID]); 426 427 /* Install low-level interrupt handlers for all of our IRQs. */ 428 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) { 429 if (i == ICU_SLAVEID) 430 continue; 431 ai->at_intsrc.is_count = &ai->at_count; 432 ai->at_intsrc.is_straycount = &ai->at_straycount; 433 setidt(((struct atpic *)ai->at_intsrc.is_pic)->at_intbase + 434 ai->at_irq, ai->at_intr, SDT_ATPIC, SEL_KPL, GSEL_ATPIC); 435 } 436 437 #ifdef DEV_MCA 438 /* For MCA systems, all interrupts are level triggered. */ 439 if (MCA_system) 440 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 441 ai->at_trigger = INTR_TRIGGER_LEVEL; 442 else 443 #endif 444 445 #ifdef PC98 446 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 447 switch (i) { 448 case 0: 449 case 1: 450 case 7: 451 case 8: 452 ai->at_trigger = INTR_TRIGGER_EDGE; 453 break; 454 default: 455 ai->at_trigger = INTR_TRIGGER_LEVEL; 456 break; 457 } 458 #else 459 /* 460 * Look for an ELCR. If we find one, update the trigger modes. 461 * If we don't find one, assume that IRQs 0, 1, 2, and 13 are 462 * edge triggered and that everything else is level triggered. 463 * We only use the trigger information to reprogram the ELCR if 464 * we have one and as an optimization to avoid masking edge 465 * triggered interrupts. For the case that we don't have an ELCR, 466 * it doesn't hurt to mask an edge triggered interrupt, so we 467 * assume level trigger for any interrupt that we aren't sure is 468 * edge triggered. 469 */ 470 if (elcr_found) { 471 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 472 ai->at_trigger = elcr_read_trigger(i); 473 } else { 474 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 475 switch (i) { 476 case 0: 477 case 1: 478 case 2: 479 case 8: 480 case 13: 481 ai->at_trigger = INTR_TRIGGER_EDGE; 482 break; 483 default: 484 ai->at_trigger = INTR_TRIGGER_LEVEL; 485 break; 486 } 487 } 488 #endif /* PC98 */ 489 } 490 491 static void 492 atpic_init(void *dummy __unused) 493 { 494 struct atpic_intsrc *ai; 495 int i; 496 497 /* 498 * Register our PICs, even if we aren't going to use any of their 499 * pins so that they are suspended and resumed. 500 */ 501 if (intr_register_pic(&atpics[0].at_pic) != 0 || 502 intr_register_pic(&atpics[1].at_pic) != 0) 503 panic("Unable to register ATPICs"); 504 505 /* 506 * If any of the ISA IRQs have an interrupt source already, then 507 * assume that the APICs are being used and don't register any 508 * of our interrupt sources. This makes sure we don't accidentally 509 * use mixed mode. The "accidental" use could otherwise occur on 510 * machines that route the ACPI SCI interrupt to a different ISA 511 * IRQ (at least one machines routes it to IRQ 13) thus disabling 512 * that APIC ISA routing and allowing the ATPIC source for that IRQ 513 * to leak through. We used to depend on this feature for routing 514 * IRQ0 via mixed mode, but now we don't use mixed mode at all. 515 */ 516 for (i = 0; i < NUM_ISA_IRQS; i++) 517 if (intr_lookup_source(i) != NULL) 518 return; 519 520 /* Loop through all interrupt sources and add them. */ 521 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) { 522 if (i == ICU_SLAVEID) 523 continue; 524 intr_register_source(&ai->at_intsrc); 525 } 526 } 527 SYSINIT(atpic_init, SI_SUB_INTR, SI_ORDER_SECOND + 1, atpic_init, NULL); 528 529 void 530 atpic_handle_intr(u_int vector, struct trapframe *frame) 531 { 532 struct intsrc *isrc; 533 534 KASSERT(vector < NUM_ISA_IRQS, ("unknown int %u\n", vector)); 535 isrc = &atintrs[vector].at_intsrc; 536 537 /* 538 * If we don't have an event, see if this is a spurious 539 * interrupt. 540 */ 541 if (isrc->is_event == NULL && (vector == 7 || vector == 15)) { 542 int port, isr; 543 544 /* 545 * Read the ISR register to see if IRQ 7/15 is really 546 * pending. Reset read register back to IRR when done. 547 */ 548 port = ((struct atpic *)isrc->is_pic)->at_ioaddr; 549 spinlock_enter(); 550 outb(port, OCW3_SEL | OCW3_RR | OCW3_RIS); 551 isr = inb(port); 552 outb(port, OCW3_SEL | OCW3_RR); 553 spinlock_exit(); 554 if ((isr & IRQ_MASK(7)) == 0) 555 return; 556 } 557 intr_execute_handlers(isrc, frame); 558 } 559 560 #ifdef DEV_ISA 561 /* 562 * Bus attachment for the ISA PIC. 563 */ 564 static struct isa_pnp_id atpic_ids[] = { 565 { 0x0000d041 /* PNP0000 */, "AT interrupt controller" }, 566 { 0 } 567 }; 568 569 static int 570 atpic_probe(device_t dev) 571 { 572 int result; 573 574 result = ISA_PNP_PROBE(device_get_parent(dev), dev, atpic_ids); 575 if (result <= 0) 576 device_quiet(dev); 577 return (result); 578 } 579 580 /* 581 * We might be granted IRQ 2, as this is typically consumed by chaining 582 * between the two PIC components. If we're using the APIC, however, 583 * this may not be the case, and as such we should free the resource. 584 * (XXX untested) 585 * 586 * The generic ISA attachment code will handle allocating any other resources 587 * that we don't explicitly claim here. 588 */ 589 static int 590 atpic_attach(device_t dev) 591 { 592 struct resource *res; 593 int rid; 594 595 /* Try to allocate our IRQ and then free it. */ 596 rid = 0; 597 res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, 0); 598 if (res != NULL) 599 bus_release_resource(dev, SYS_RES_IRQ, rid, res); 600 return (0); 601 } 602 603 static device_method_t atpic_methods[] = { 604 /* Device interface */ 605 DEVMETHOD(device_probe, atpic_probe), 606 DEVMETHOD(device_attach, atpic_attach), 607 DEVMETHOD(device_detach, bus_generic_detach), 608 DEVMETHOD(device_shutdown, bus_generic_shutdown), 609 DEVMETHOD(device_suspend, bus_generic_suspend), 610 DEVMETHOD(device_resume, bus_generic_resume), 611 { 0, 0 } 612 }; 613 614 static driver_t atpic_driver = { 615 "atpic", 616 atpic_methods, 617 1, /* no softc */ 618 }; 619 620 static devclass_t atpic_devclass; 621 622 DRIVER_MODULE(atpic, isa, atpic_driver, atpic_devclass, 0, 0); 623 #ifndef PC98 624 DRIVER_MODULE(atpic, acpi, atpic_driver, atpic_devclass, 0, 0); 625 #endif 626 627 /* 628 * Return a bitmap of the current interrupt requests. This is 8259-specific 629 * and is only suitable for use at probe time. 630 */ 631 intrmask_t 632 isa_irq_pending(void) 633 { 634 u_char irr1; 635 u_char irr2; 636 637 irr1 = inb(IO_ICU1); 638 irr2 = inb(IO_ICU2); 639 return ((irr2 << 8) | irr1); 640 } 641 #endif /* DEV_ISA */
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