1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 /* 29 * PIC driver for the 8259A Master and Slave PICs in PC/AT machines. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_auto_eoi.h" 36 #include "opt_isa.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bus.h> 41 #include <sys/interrupt.h> 42 #include <sys/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/module.h> 45 46 #include <machine/cpufunc.h> 47 #include <machine/frame.h> 48 #include <machine/intr_machdep.h> 49 #include <machine/md_var.h> 50 #include <machine/resource.h> 51 #include <machine/segments.h> 52 53 #include <dev/ic/i8259.h> 54 #include <x86/isa/icu.h> 55 #include <isa/isareg.h> 56 #include <isa/isavar.h> 57 58 #ifdef __amd64__ 59 #define SDT_ATPIC SDT_SYSIGT 60 #define GSEL_ATPIC 0 61 #else 62 #define SDT_ATPIC SDT_SYS386IGT 63 #define GSEL_ATPIC GSEL(GCODE_SEL, SEL_KPL) 64 #endif 65 66 #define MASTER 0 67 #define SLAVE 1 68 69 #define IMEN_MASK(ai) (IRQ_MASK((ai)->at_irq)) 70 71 #define NUM_ISA_IRQS 16 72 73 static void atpic_init(void *dummy); 74 75 inthand_t 76 IDTVEC(atpic_intr0), IDTVEC(atpic_intr1), IDTVEC(atpic_intr2), 77 IDTVEC(atpic_intr3), IDTVEC(atpic_intr4), IDTVEC(atpic_intr5), 78 IDTVEC(atpic_intr6), IDTVEC(atpic_intr7), IDTVEC(atpic_intr8), 79 IDTVEC(atpic_intr9), IDTVEC(atpic_intr10), IDTVEC(atpic_intr11), 80 IDTVEC(atpic_intr12), IDTVEC(atpic_intr13), IDTVEC(atpic_intr14), 81 IDTVEC(atpic_intr15); 82 /* XXXKIB i386 uses stubs until pti comes */ 83 inthand_t 84 IDTVEC(atpic_intr0_pti), IDTVEC(atpic_intr1_pti), 85 IDTVEC(atpic_intr2_pti), IDTVEC(atpic_intr3_pti), 86 IDTVEC(atpic_intr4_pti), IDTVEC(atpic_intr5_pti), 87 IDTVEC(atpic_intr6_pti), IDTVEC(atpic_intr7_pti), 88 IDTVEC(atpic_intr8_pti), IDTVEC(atpic_intr9_pti), 89 IDTVEC(atpic_intr10_pti), IDTVEC(atpic_intr11_pti), 90 IDTVEC(atpic_intr12_pti), IDTVEC(atpic_intr13_pti), 91 IDTVEC(atpic_intr14_pti), IDTVEC(atpic_intr15_pti); 92 93 #define IRQ(ap, ai) ((ap)->at_irqbase + (ai)->at_irq) 94 95 #define ATPIC(io, base, eoi) { \ 96 .at_pic = { \ 97 .pic_register_sources = atpic_register_sources, \ 98 .pic_enable_source = atpic_enable_source, \ 99 .pic_disable_source = atpic_disable_source, \ 100 .pic_eoi_source = (eoi), \ 101 .pic_enable_intr = atpic_enable_intr, \ 102 .pic_disable_intr = atpic_disable_intr, \ 103 .pic_vector = atpic_vector, \ 104 .pic_source_pending = atpic_source_pending, \ 105 .pic_resume = atpic_resume, \ 106 .pic_config_intr = atpic_config_intr, \ 107 .pic_assign_cpu = atpic_assign_cpu \ 108 }, \ 109 .at_ioaddr = (io), \ 110 .at_irqbase = (base), \ 111 .at_intbase = IDT_IO_INTS + (base), \ 112 .at_imen = 0xff, \ 113 } 114 115 #define INTSRC(irq) \ 116 { { &atpics[(irq) / 8].at_pic }, IDTVEC(atpic_intr ## irq ), \ 117 IDTVEC(atpic_intr ## irq ## _pti), (irq) % 8 } 118 119 struct atpic { 120 struct pic at_pic; 121 int at_ioaddr; 122 int at_irqbase; 123 uint8_t at_intbase; 124 uint8_t at_imen; 125 }; 126 127 struct atpic_intsrc { 128 struct intsrc at_intsrc; 129 inthand_t *at_intr, *at_intr_pti; 130 int at_irq; /* Relative to PIC base. */ 131 enum intr_trigger at_trigger; 132 u_long at_count; 133 u_long at_straycount; 134 }; 135 136 static void atpic_register_sources(struct pic *pic); 137 static void atpic_enable_source(struct intsrc *isrc); 138 static void atpic_disable_source(struct intsrc *isrc, int eoi); 139 static void atpic_eoi_master(struct intsrc *isrc); 140 static void atpic_eoi_slave(struct intsrc *isrc); 141 static void atpic_enable_intr(struct intsrc *isrc); 142 static void atpic_disable_intr(struct intsrc *isrc); 143 static int atpic_vector(struct intsrc *isrc); 144 static void atpic_resume(struct pic *pic, bool suspend_cancelled); 145 static int atpic_source_pending(struct intsrc *isrc); 146 static int atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig, 147 enum intr_polarity pol); 148 static int atpic_assign_cpu(struct intsrc *isrc, u_int apic_id); 149 static void i8259_init(struct atpic *pic, int slave); 150 151 static struct atpic atpics[] = { 152 ATPIC(IO_ICU1, 0, atpic_eoi_master), 153 ATPIC(IO_ICU2, 8, atpic_eoi_slave) 154 }; 155 156 static struct atpic_intsrc atintrs[] = { 157 INTSRC(0), 158 INTSRC(1), 159 INTSRC(2), 160 INTSRC(3), 161 INTSRC(4), 162 INTSRC(5), 163 INTSRC(6), 164 INTSRC(7), 165 INTSRC(8), 166 INTSRC(9), 167 INTSRC(10), 168 INTSRC(11), 169 INTSRC(12), 170 INTSRC(13), 171 INTSRC(14), 172 INTSRC(15), 173 }; 174 175 CTASSERT(nitems(atintrs) == NUM_ISA_IRQS); 176 177 static __inline void 178 _atpic_eoi_master(struct intsrc *isrc) 179 { 180 181 KASSERT(isrc->is_pic == &atpics[MASTER].at_pic, 182 ("%s: mismatched pic", __func__)); 183 #ifndef AUTO_EOI_1 184 outb(atpics[MASTER].at_ioaddr, OCW2_EOI); 185 #endif 186 } 187 188 /* 189 * The data sheet says no auto-EOI on slave, but it sometimes works. 190 * So, if AUTO_EOI_2 is enabled, we use it. 191 */ 192 static __inline void 193 _atpic_eoi_slave(struct intsrc *isrc) 194 { 195 196 KASSERT(isrc->is_pic == &atpics[SLAVE].at_pic, 197 ("%s: mismatched pic", __func__)); 198 #ifndef AUTO_EOI_2 199 outb(atpics[SLAVE].at_ioaddr, OCW2_EOI); 200 #ifndef AUTO_EOI_1 201 outb(atpics[MASTER].at_ioaddr, OCW2_EOI); 202 #endif 203 #endif 204 } 205 206 static void 207 atpic_register_sources(struct pic *pic) 208 { 209 struct atpic *ap = (struct atpic *)pic; 210 struct atpic_intsrc *ai; 211 int i; 212 213 /* 214 * If any of the ISA IRQs have an interrupt source already, then 215 * assume that the I/O APICs are being used and don't register any 216 * of our interrupt sources. This makes sure we don't accidentally 217 * use mixed mode. The "accidental" use could otherwise occur on 218 * machines that route the ACPI SCI interrupt to a different ISA 219 * IRQ (at least one machine routes it to IRQ 13) thus disabling 220 * that APIC ISA routing and allowing the ATPIC source for that IRQ 221 * to leak through. We used to depend on this feature for routing 222 * IRQ0 via mixed mode, but now we don't use mixed mode at all. 223 * 224 * To avoid the slave not register sources after the master 225 * registers its sources, register all IRQs when this function is 226 * called on the master. 227 */ 228 if (ap != &atpics[MASTER]) 229 return; 230 for (i = 0; i < NUM_ISA_IRQS; i++) 231 if (intr_lookup_source(i) != NULL) 232 return; 233 234 /* Loop through all interrupt sources and add them. */ 235 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) { 236 if (i == ICU_SLAVEID) 237 continue; 238 intr_register_source(&ai->at_intsrc); 239 } 240 } 241 242 static void 243 atpic_enable_source(struct intsrc *isrc) 244 { 245 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 246 struct atpic *ap = (struct atpic *)isrc->is_pic; 247 248 spinlock_enter(); 249 if (ap->at_imen & IMEN_MASK(ai)) { 250 ap->at_imen &= ~IMEN_MASK(ai); 251 outb(ap->at_ioaddr + ICU_IMR_OFFSET, ap->at_imen); 252 } 253 spinlock_exit(); 254 } 255 256 static void 257 atpic_disable_source(struct intsrc *isrc, int eoi) 258 { 259 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 260 struct atpic *ap = (struct atpic *)isrc->is_pic; 261 262 spinlock_enter(); 263 if (ai->at_trigger != INTR_TRIGGER_EDGE) { 264 ap->at_imen |= IMEN_MASK(ai); 265 outb(ap->at_ioaddr + ICU_IMR_OFFSET, ap->at_imen); 266 } 267 268 /* 269 * Take care to call these functions directly instead of through 270 * a function pointer. All of the referenced variables should 271 * still be hot in the cache. 272 */ 273 if (eoi == PIC_EOI) { 274 if (isrc->is_pic == &atpics[MASTER].at_pic) 275 _atpic_eoi_master(isrc); 276 else 277 _atpic_eoi_slave(isrc); 278 } 279 280 spinlock_exit(); 281 } 282 283 static void 284 atpic_eoi_master(struct intsrc *isrc) 285 { 286 #ifndef AUTO_EOI_1 287 spinlock_enter(); 288 _atpic_eoi_master(isrc); 289 spinlock_exit(); 290 #endif 291 } 292 293 static void 294 atpic_eoi_slave(struct intsrc *isrc) 295 { 296 #ifndef AUTO_EOI_2 297 spinlock_enter(); 298 _atpic_eoi_slave(isrc); 299 spinlock_exit(); 300 #endif 301 } 302 303 static void 304 atpic_enable_intr(struct intsrc *isrc) 305 { 306 } 307 308 static void 309 atpic_disable_intr(struct intsrc *isrc) 310 { 311 } 312 313 static int 314 atpic_vector(struct intsrc *isrc) 315 { 316 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 317 struct atpic *ap = (struct atpic *)isrc->is_pic; 318 319 return (IRQ(ap, ai)); 320 } 321 322 static int 323 atpic_source_pending(struct intsrc *isrc) 324 { 325 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 326 struct atpic *ap = (struct atpic *)isrc->is_pic; 327 328 return (inb(ap->at_ioaddr) & IMEN_MASK(ai)); 329 } 330 331 static void 332 atpic_resume(struct pic *pic, bool suspend_cancelled) 333 { 334 struct atpic *ap = (struct atpic *)pic; 335 336 i8259_init(ap, ap == &atpics[SLAVE]); 337 if (ap == &atpics[SLAVE] && elcr_found) 338 elcr_resume(); 339 } 340 341 static int 342 atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig, 343 enum intr_polarity pol) 344 { 345 struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc; 346 u_int vector; 347 348 /* Map conforming values to edge/hi and sanity check the values. */ 349 if (trig == INTR_TRIGGER_CONFORM) 350 trig = INTR_TRIGGER_EDGE; 351 if (pol == INTR_POLARITY_CONFORM) 352 pol = INTR_POLARITY_HIGH; 353 vector = atpic_vector(isrc); 354 if ((trig == INTR_TRIGGER_EDGE && pol == INTR_POLARITY_LOW) || 355 (trig == INTR_TRIGGER_LEVEL && pol == INTR_POLARITY_HIGH)) { 356 printf( 357 "atpic: Mismatched config for IRQ%u: trigger %s, polarity %s\n", 358 vector, trig == INTR_TRIGGER_EDGE ? "edge" : "level", 359 pol == INTR_POLARITY_HIGH ? "high" : "low"); 360 return (EINVAL); 361 } 362 363 /* If there is no change, just return. */ 364 if (ai->at_trigger == trig) 365 return (0); 366 367 /* 368 * Certain IRQs can never be level/lo, so don't try to set them 369 * that way if asked. At least some ELCR registers ignore setting 370 * these bits as well. 371 */ 372 if ((vector == 0 || vector == 1 || vector == 2 || vector == 13) && 373 trig == INTR_TRIGGER_LEVEL) { 374 if (bootverbose) 375 printf( 376 "atpic: Ignoring invalid level/low configuration for IRQ%u\n", 377 vector); 378 return (EINVAL); 379 } 380 if (!elcr_found) { 381 if (bootverbose) 382 printf("atpic: No ELCR to configure IRQ%u as %s\n", 383 vector, trig == INTR_TRIGGER_EDGE ? "edge/high" : 384 "level/low"); 385 return (ENXIO); 386 } 387 if (bootverbose) 388 printf("atpic: Programming IRQ%u as %s\n", vector, 389 trig == INTR_TRIGGER_EDGE ? "edge/high" : "level/low"); 390 spinlock_enter(); 391 elcr_write_trigger(atpic_vector(isrc), trig); 392 ai->at_trigger = trig; 393 spinlock_exit(); 394 return (0); 395 } 396 397 static int 398 atpic_assign_cpu(struct intsrc *isrc, u_int apic_id) 399 { 400 401 /* 402 * 8259A's are only used in UP in which case all interrupts always 403 * go to the sole CPU and this function shouldn't even be called. 404 */ 405 panic("%s: bad cookie", __func__); 406 } 407 408 static void 409 i8259_init(struct atpic *pic, int slave) 410 { 411 int imr_addr; 412 413 /* Reset the PIC and program with next four bytes. */ 414 spinlock_enter(); 415 outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4); 416 imr_addr = pic->at_ioaddr + ICU_IMR_OFFSET; 417 418 /* Start vector. */ 419 outb(imr_addr, pic->at_intbase); 420 421 /* 422 * Setup slave links. For the master pic, indicate what line 423 * the slave is configured on. For the slave indicate 424 * which line on the master we are connected to. 425 */ 426 if (slave) 427 outb(imr_addr, ICU_SLAVEID); 428 else 429 outb(imr_addr, IRQ_MASK(ICU_SLAVEID)); 430 431 /* Set mode. */ 432 if (slave) 433 outb(imr_addr, SLAVE_MODE); 434 else 435 outb(imr_addr, MASTER_MODE); 436 437 /* Set interrupt enable mask. */ 438 outb(imr_addr, pic->at_imen); 439 440 /* Reset is finished, default to IRR on read. */ 441 outb(pic->at_ioaddr, OCW3_SEL | OCW3_RR); 442 443 /* OCW2_L1 sets priority order to 3-7, 0-2 (com2 first). */ 444 if (!slave) 445 outb(pic->at_ioaddr, OCW2_R | OCW2_SL | OCW2_L1); 446 447 spinlock_exit(); 448 } 449 450 void 451 atpic_startup(void) 452 { 453 struct atpic_intsrc *ai; 454 int i; 455 456 /* Start off with all interrupts disabled. */ 457 i8259_init(&atpics[MASTER], 0); 458 i8259_init(&atpics[SLAVE], 1); 459 atpic_enable_source((struct intsrc *)&atintrs[ICU_SLAVEID]); 460 461 /* Install low-level interrupt handlers for all of our IRQs. */ 462 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) { 463 if (i == ICU_SLAVEID) 464 continue; 465 ai->at_intsrc.is_count = &ai->at_count; 466 ai->at_intsrc.is_straycount = &ai->at_straycount; 467 setidt(((struct atpic *)ai->at_intsrc.is_pic)->at_intbase + 468 ai->at_irq, pti ? ai->at_intr_pti : ai->at_intr, SDT_ATPIC, 469 SEL_KPL, GSEL_ATPIC); 470 } 471 472 /* 473 * Look for an ELCR. If we find one, update the trigger modes. 474 * If we don't find one, assume that IRQs 0, 1, 2, and 13 are 475 * edge triggered and that everything else is level triggered. 476 * We only use the trigger information to reprogram the ELCR if 477 * we have one and as an optimization to avoid masking edge 478 * triggered interrupts. For the case that we don't have an ELCR, 479 * it doesn't hurt to mask an edge triggered interrupt, so we 480 * assume level trigger for any interrupt that we aren't sure is 481 * edge triggered. 482 */ 483 if (elcr_found) { 484 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 485 ai->at_trigger = elcr_read_trigger(i); 486 } else { 487 for (i = 0, ai = atintrs; i < NUM_ISA_IRQS; i++, ai++) 488 switch (i) { 489 case 0: 490 case 1: 491 case 2: 492 case 8: 493 case 13: 494 ai->at_trigger = INTR_TRIGGER_EDGE; 495 break; 496 default: 497 ai->at_trigger = INTR_TRIGGER_LEVEL; 498 break; 499 } 500 } 501 } 502 503 static void 504 atpic_init(void *dummy __unused) 505 { 506 507 /* 508 * Register our PICs, even if we aren't going to use any of their 509 * pins so that they are suspended and resumed. 510 */ 511 if (intr_register_pic(&atpics[0].at_pic) != 0 || 512 intr_register_pic(&atpics[1].at_pic) != 0) 513 panic("Unable to register ATPICs"); 514 515 if (num_io_irqs == 0) 516 num_io_irqs = NUM_ISA_IRQS; 517 } 518 SYSINIT(atpic_init, SI_SUB_INTR, SI_ORDER_FOURTH, atpic_init, NULL); 519 520 void 521 atpic_handle_intr(u_int vector, struct trapframe *frame) 522 { 523 struct intsrc *isrc; 524 525 KASSERT(vector < NUM_ISA_IRQS, ("unknown int %u\n", vector)); 526 isrc = &atintrs[vector].at_intsrc; 527 528 /* 529 * If we don't have an event, see if this is a spurious 530 * interrupt. 531 */ 532 if (isrc->is_event == NULL && (vector == 7 || vector == 15)) { 533 int port, isr; 534 535 /* 536 * Read the ISR register to see if IRQ 7/15 is really 537 * pending. Reset read register back to IRR when done. 538 */ 539 port = ((struct atpic *)isrc->is_pic)->at_ioaddr; 540 spinlock_enter(); 541 outb(port, OCW3_SEL | OCW3_RR | OCW3_RIS); 542 isr = inb(port); 543 outb(port, OCW3_SEL | OCW3_RR); 544 spinlock_exit(); 545 if ((isr & IRQ_MASK(7)) == 0) 546 return; 547 } 548 intr_execute_handlers(isrc, frame); 549 } 550 551 #ifdef DEV_ISA 552 /* 553 * Bus attachment for the ISA PIC. 554 */ 555 static struct isa_pnp_id atpic_ids[] = { 556 { 0x0000d041 /* PNP0000 */, "AT interrupt controller" }, 557 { 0 } 558 }; 559 560 static int 561 atpic_probe(device_t dev) 562 { 563 int result; 564 565 result = ISA_PNP_PROBE(device_get_parent(dev), dev, atpic_ids); 566 if (result <= 0) 567 device_quiet(dev); 568 return (result); 569 } 570 571 /* 572 * We might be granted IRQ 2, as this is typically consumed by chaining 573 * between the two PIC components. If we're using the APIC, however, 574 * this may not be the case, and as such we should free the resource. 575 * (XXX untested) 576 * 577 * The generic ISA attachment code will handle allocating any other resources 578 * that we don't explicitly claim here. 579 */ 580 static int 581 atpic_attach(device_t dev) 582 { 583 struct resource *res; 584 int rid; 585 586 /* Try to allocate our IRQ and then free it. */ 587 rid = 0; 588 res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, 0); 589 if (res != NULL) 590 bus_release_resource(dev, SYS_RES_IRQ, rid, res); 591 return (0); 592 } 593 594 /* 595 * Return a bitmap of the current interrupt requests. This is 8259-specific 596 * and is only suitable for use at probe time. 597 */ 598 intrmask_t 599 isa_irq_pending(void) 600 { 601 u_char irr1; 602 u_char irr2; 603 604 irr1 = inb(IO_ICU1); 605 irr2 = inb(IO_ICU2); 606 return ((irr2 << 8) | irr1); 607 } 608 609 static device_method_t atpic_methods[] = { 610 /* Device interface */ 611 DEVMETHOD(device_probe, atpic_probe), 612 DEVMETHOD(device_attach, atpic_attach), 613 DEVMETHOD(device_detach, bus_generic_detach), 614 DEVMETHOD(device_shutdown, bus_generic_shutdown), 615 DEVMETHOD(device_suspend, bus_generic_suspend), 616 DEVMETHOD(device_resume, bus_generic_resume), 617 { 0, 0 } 618 }; 619 620 static driver_t atpic_driver = { 621 "atpic", 622 atpic_methods, 623 1, /* no softc */ 624 }; 625 626 static devclass_t atpic_devclass; 627 628 DRIVER_MODULE(atpic, isa, atpic_driver, atpic_devclass, 0, 0); 629 DRIVER_MODULE(atpic, acpi, atpic_driver, atpic_devclass, 0, 0); 630 ISA_PNP_INFO(atpic_ids); 631 #endif /* DEV_ISA */ 632