1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2006 Yahoo!, Inc. 5 * All rights reserved. 6 * Written by: John Baldwin <jhb@FreeBSD.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Support for PCI Message Signalled Interrupts (MSI). MSI interrupts on 35 * x86 are basically APIC messages that the northbridge delivers directly 36 * to the local APICs as if they had come from an I/O APIC. 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "opt_acpi.h" 43 #include "opt_iommu.h" 44 45 #include <sys/param.h> 46 #include <sys/bus.h> 47 #include <sys/kernel.h> 48 #include <sys/limits.h> 49 #include <sys/lock.h> 50 #include <sys/malloc.h> 51 #include <sys/mutex.h> 52 #include <sys/sx.h> 53 #include <sys/sysctl.h> 54 #include <sys/systm.h> 55 #include <x86/apicreg.h> 56 #include <machine/cputypes.h> 57 #include <machine/md_var.h> 58 #include <machine/frame.h> 59 #include <machine/intr_machdep.h> 60 #include <x86/apicvar.h> 61 #include <x86/iommu/iommu_intrmap.h> 62 #include <machine/specialreg.h> 63 #include <dev/pci/pcivar.h> 64 65 /* Fields in address for Intel MSI messages. */ 66 #define MSI_INTEL_ADDR_DEST 0x000ff000 67 #define MSI_INTEL_ADDR_RH 0x00000008 68 # define MSI_INTEL_ADDR_RH_ON 0x00000008 69 # define MSI_INTEL_ADDR_RH_OFF 0x00000000 70 #define MSI_INTEL_ADDR_DM 0x00000004 71 # define MSI_INTEL_ADDR_DM_PHYSICAL 0x00000000 72 # define MSI_INTEL_ADDR_DM_LOGICAL 0x00000004 73 74 /* Fields in data for Intel MSI messages. */ 75 #define MSI_INTEL_DATA_TRGRMOD IOART_TRGRMOD /* Trigger mode. */ 76 # define MSI_INTEL_DATA_TRGREDG IOART_TRGREDG 77 # define MSI_INTEL_DATA_TRGRLVL IOART_TRGRLVL 78 #define MSI_INTEL_DATA_LEVEL 0x00004000 /* Polarity. */ 79 # define MSI_INTEL_DATA_DEASSERT 0x00000000 80 # define MSI_INTEL_DATA_ASSERT 0x00004000 81 #define MSI_INTEL_DATA_DELMOD IOART_DELMOD /* Delivery mode. */ 82 # define MSI_INTEL_DATA_DELFIXED IOART_DELFIXED 83 # define MSI_INTEL_DATA_DELLOPRI IOART_DELLOPRI 84 # define MSI_INTEL_DATA_DELSMI IOART_DELSMI 85 # define MSI_INTEL_DATA_DELNMI IOART_DELNMI 86 # define MSI_INTEL_DATA_DELINIT IOART_DELINIT 87 # define MSI_INTEL_DATA_DELEXINT IOART_DELEXINT 88 #define MSI_INTEL_DATA_INTVEC IOART_INTVEC /* Interrupt vector. */ 89 90 /* 91 * Build Intel MSI message and data values from a source. AMD64 systems 92 * seem to be compatible, so we use the same function for both. 93 */ 94 #define INTEL_ADDR(msi) \ 95 (MSI_INTEL_ADDR_BASE | (msi)->msi_cpu << 12 | \ 96 MSI_INTEL_ADDR_RH_OFF | MSI_INTEL_ADDR_DM_PHYSICAL) 97 #define INTEL_DATA(msi) \ 98 (MSI_INTEL_DATA_TRGREDG | MSI_INTEL_DATA_DELFIXED | (msi)->msi_vector) 99 100 static MALLOC_DEFINE(M_MSI, "msi", "PCI MSI"); 101 102 /* 103 * MSI sources are bunched into groups. This is because MSI forces 104 * all of the messages to share the address and data registers and 105 * thus certain properties (such as the local APIC ID target on x86). 106 * Each group has a 'first' source that contains information global to 107 * the group. These fields are marked with (g) below. 108 * 109 * Note that local APIC ID is kind of special. Each message will be 110 * assigned an ID by the system; however, a group will use the ID from 111 * the first message. 112 * 113 * For MSI-X, each message is isolated. 114 */ 115 struct msi_intsrc { 116 struct intsrc msi_intsrc; 117 device_t msi_dev; /* Owning device. (g) */ 118 struct msi_intsrc *msi_first; /* First source in group. */ 119 u_int msi_irq; /* IRQ cookie. */ 120 u_int msi_msix; /* MSI-X message. */ 121 u_int msi_vector:8; /* IDT vector. */ 122 u_int msi_cpu; /* Local APIC ID. (g) */ 123 u_int msi_count:8; /* Messages in this group. (g) */ 124 u_int msi_maxcount:8; /* Alignment for this group. (g) */ 125 u_int *msi_irqs; /* Group's IRQ list. (g) */ 126 u_int msi_remap_cookie; 127 }; 128 129 static void msi_create_source(void); 130 static void msi_enable_source(struct intsrc *isrc); 131 static void msi_disable_source(struct intsrc *isrc, int eoi); 132 static void msi_eoi_source(struct intsrc *isrc); 133 static void msi_enable_intr(struct intsrc *isrc); 134 static void msi_disable_intr(struct intsrc *isrc); 135 static int msi_vector(struct intsrc *isrc); 136 static int msi_source_pending(struct intsrc *isrc); 137 static int msi_config_intr(struct intsrc *isrc, enum intr_trigger trig, 138 enum intr_polarity pol); 139 static int msi_assign_cpu(struct intsrc *isrc, u_int apic_id); 140 141 struct pic msi_pic = { 142 .pic_enable_source = msi_enable_source, 143 .pic_disable_source = msi_disable_source, 144 .pic_eoi_source = msi_eoi_source, 145 .pic_enable_intr = msi_enable_intr, 146 .pic_disable_intr = msi_disable_intr, 147 .pic_vector = msi_vector, 148 .pic_source_pending = msi_source_pending, 149 .pic_suspend = NULL, 150 .pic_resume = NULL, 151 .pic_config_intr = msi_config_intr, 152 .pic_assign_cpu = msi_assign_cpu, 153 .pic_reprogram_pin = NULL, 154 }; 155 156 u_int first_msi_irq; 157 SYSCTL_UINT(_machdep, OID_AUTO, first_msi_irq, CTLFLAG_RD, &first_msi_irq, 0, 158 "Number of first IRQ reserved for MSI and MSI-X interrupts"); 159 160 u_int num_msi_irqs = 2048; 161 SYSCTL_UINT(_machdep, OID_AUTO, num_msi_irqs, CTLFLAG_RDTUN, &num_msi_irqs, 0, 162 "Number of IRQs reserved for MSI and MSI-X interrupts"); 163 164 #ifdef SMP 165 /** 166 * Xen hypervisors prior to 4.6.0 do not properly handle updates to 167 * enabled MSI-X table entries. Allow migration of MSI-X interrupts 168 * to be disabled via a tunable. Values have the following meaning: 169 * 170 * -1: automatic detection by FreeBSD 171 * 0: enable migration 172 * 1: disable migration 173 */ 174 int msix_disable_migration = -1; 175 SYSCTL_INT(_machdep, OID_AUTO, disable_msix_migration, CTLFLAG_RDTUN, 176 &msix_disable_migration, 0, 177 "Disable migration of MSI-X interrupts between CPUs"); 178 #endif 179 180 static int msi_enabled; 181 static u_int msi_last_irq; 182 static struct mtx msi_lock; 183 184 static void 185 msi_enable_source(struct intsrc *isrc) 186 { 187 } 188 189 static void 190 msi_disable_source(struct intsrc *isrc, int eoi) 191 { 192 193 if (eoi == PIC_EOI) 194 lapic_eoi(); 195 } 196 197 static void 198 msi_eoi_source(struct intsrc *isrc) 199 { 200 201 lapic_eoi(); 202 } 203 204 static void 205 msi_enable_intr(struct intsrc *isrc) 206 { 207 struct msi_intsrc *msi = (struct msi_intsrc *)isrc; 208 209 apic_enable_vector(msi->msi_cpu, msi->msi_vector); 210 } 211 212 static void 213 msi_disable_intr(struct intsrc *isrc) 214 { 215 struct msi_intsrc *msi = (struct msi_intsrc *)isrc; 216 217 apic_disable_vector(msi->msi_cpu, msi->msi_vector); 218 } 219 220 static int 221 msi_vector(struct intsrc *isrc) 222 { 223 struct msi_intsrc *msi = (struct msi_intsrc *)isrc; 224 225 return (msi->msi_irq); 226 } 227 228 static int 229 msi_source_pending(struct intsrc *isrc) 230 { 231 232 return (0); 233 } 234 235 static int 236 msi_config_intr(struct intsrc *isrc, enum intr_trigger trig, 237 enum intr_polarity pol) 238 { 239 240 return (ENODEV); 241 } 242 243 static int 244 msi_assign_cpu(struct intsrc *isrc, u_int apic_id) 245 { 246 struct msi_intsrc *sib, *msi = (struct msi_intsrc *)isrc; 247 int old_vector; 248 u_int old_id; 249 int i, vector; 250 251 /* 252 * Only allow CPUs to be assigned to the first message for an 253 * MSI group. 254 */ 255 if (msi->msi_first != msi) 256 return (EINVAL); 257 258 #ifdef SMP 259 if (msix_disable_migration && msi->msi_msix) 260 return (EINVAL); 261 #endif 262 263 /* Store information to free existing irq. */ 264 old_vector = msi->msi_vector; 265 old_id = msi->msi_cpu; 266 if (old_id == apic_id) 267 return (0); 268 269 /* Allocate IDT vectors on this cpu. */ 270 if (msi->msi_count > 1) { 271 KASSERT(msi->msi_msix == 0, ("MSI-X message group")); 272 vector = apic_alloc_vectors(apic_id, msi->msi_irqs, 273 msi->msi_count, msi->msi_maxcount); 274 } else 275 vector = apic_alloc_vector(apic_id, msi->msi_irq); 276 if (vector == 0) 277 return (ENOSPC); 278 279 msi->msi_cpu = apic_id; 280 msi->msi_vector = vector; 281 if (msi->msi_intsrc.is_handlers > 0) 282 apic_enable_vector(msi->msi_cpu, msi->msi_vector); 283 if (bootverbose) 284 printf("msi: Assigning %s IRQ %d to local APIC %u vector %u\n", 285 msi->msi_msix ? "MSI-X" : "MSI", msi->msi_irq, 286 msi->msi_cpu, msi->msi_vector); 287 for (i = 1; i < msi->msi_count; i++) { 288 sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]); 289 sib->msi_cpu = apic_id; 290 sib->msi_vector = vector + i; 291 if (sib->msi_intsrc.is_handlers > 0) 292 apic_enable_vector(sib->msi_cpu, sib->msi_vector); 293 if (bootverbose) 294 printf( 295 "msi: Assigning MSI IRQ %d to local APIC %u vector %u\n", 296 sib->msi_irq, sib->msi_cpu, sib->msi_vector); 297 } 298 BUS_REMAP_INTR(device_get_parent(msi->msi_dev), msi->msi_dev, 299 msi->msi_irq); 300 301 /* 302 * Free the old vector after the new one is established. This is done 303 * to prevent races where we could miss an interrupt. 304 */ 305 if (msi->msi_intsrc.is_handlers > 0) 306 apic_disable_vector(old_id, old_vector); 307 apic_free_vector(old_id, old_vector, msi->msi_irq); 308 for (i = 1; i < msi->msi_count; i++) { 309 sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]); 310 if (sib->msi_intsrc.is_handlers > 0) 311 apic_disable_vector(old_id, old_vector + i); 312 apic_free_vector(old_id, old_vector + i, msi->msi_irqs[i]); 313 } 314 return (0); 315 } 316 317 void 318 msi_init(void) 319 { 320 321 /* Check if we have a supported CPU. */ 322 switch (cpu_vendor_id) { 323 case CPU_VENDOR_INTEL: 324 case CPU_VENDOR_AMD: 325 case CPU_VENDOR_HYGON: 326 break; 327 case CPU_VENDOR_CENTAUR: 328 if (CPUID_TO_FAMILY(cpu_id) == 0x6 && 329 CPUID_TO_MODEL(cpu_id) >= 0xf) 330 break; 331 /* FALLTHROUGH */ 332 default: 333 return; 334 } 335 336 #ifdef SMP 337 if (msix_disable_migration == -1) { 338 /* The default is to allow migration of MSI-X interrupts. */ 339 msix_disable_migration = 0; 340 } 341 #endif 342 343 if (num_msi_irqs == 0) 344 return; 345 346 first_msi_irq = num_io_irqs; 347 if (num_msi_irqs > UINT_MAX - first_msi_irq) 348 panic("num_msi_irqs too high"); 349 num_io_irqs = first_msi_irq + num_msi_irqs; 350 351 msi_enabled = 1; 352 intr_register_pic(&msi_pic); 353 mtx_init(&msi_lock, "msi", NULL, MTX_DEF); 354 } 355 356 static void 357 msi_create_source(void) 358 { 359 struct msi_intsrc *msi; 360 u_int irq; 361 362 mtx_lock(&msi_lock); 363 if (msi_last_irq >= num_msi_irqs) { 364 mtx_unlock(&msi_lock); 365 return; 366 } 367 irq = msi_last_irq + first_msi_irq; 368 msi_last_irq++; 369 mtx_unlock(&msi_lock); 370 371 msi = malloc(sizeof(struct msi_intsrc), M_MSI, M_WAITOK | M_ZERO); 372 msi->msi_intsrc.is_pic = &msi_pic; 373 msi->msi_irq = irq; 374 intr_register_source(&msi->msi_intsrc); 375 nexus_add_irq(irq); 376 } 377 378 /* 379 * Try to allocate 'count' interrupt sources with contiguous IDT values. 380 */ 381 int 382 msi_alloc(device_t dev, int count, int maxcount, int *irqs) 383 { 384 struct msi_intsrc *msi, *fsrc; 385 u_int cpu, domain, *mirqs; 386 int cnt, i, vector; 387 #ifdef IOMMU 388 u_int cookies[count]; 389 int error; 390 #endif 391 392 if (!msi_enabled) 393 return (ENXIO); 394 395 if (bus_get_domain(dev, &domain) != 0) 396 domain = 0; 397 398 if (count > 1) 399 mirqs = malloc(count * sizeof(*mirqs), M_MSI, M_WAITOK); 400 else 401 mirqs = NULL; 402 again: 403 mtx_lock(&msi_lock); 404 405 /* Try to find 'count' free IRQs. */ 406 cnt = 0; 407 for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) { 408 msi = (struct msi_intsrc *)intr_lookup_source(i); 409 410 /* End of allocated sources, so break. */ 411 if (msi == NULL) 412 break; 413 414 /* If this is a free one, save its IRQ in the array. */ 415 if (msi->msi_dev == NULL) { 416 irqs[cnt] = i; 417 cnt++; 418 if (cnt == count) 419 break; 420 } 421 } 422 423 /* Do we need to create some new sources? */ 424 if (cnt < count) { 425 /* If we would exceed the max, give up. */ 426 if (i + (count - cnt) > first_msi_irq + num_msi_irqs) { 427 mtx_unlock(&msi_lock); 428 free(mirqs, M_MSI); 429 return (ENXIO); 430 } 431 mtx_unlock(&msi_lock); 432 433 /* We need count - cnt more sources. */ 434 while (cnt < count) { 435 msi_create_source(); 436 cnt++; 437 } 438 goto again; 439 } 440 441 /* Ok, we now have the IRQs allocated. */ 442 KASSERT(cnt == count, ("count mismatch")); 443 444 /* Allocate 'count' IDT vectors. */ 445 cpu = intr_next_cpu(domain); 446 vector = apic_alloc_vectors(cpu, irqs, count, maxcount); 447 if (vector == 0) { 448 mtx_unlock(&msi_lock); 449 free(mirqs, M_MSI); 450 return (ENOSPC); 451 } 452 453 #ifdef IOMMU 454 mtx_unlock(&msi_lock); 455 error = iommu_alloc_msi_intr(dev, cookies, count); 456 mtx_lock(&msi_lock); 457 if (error == EOPNOTSUPP) 458 error = 0; 459 if (error != 0) { 460 for (i = 0; i < count; i++) 461 apic_free_vector(cpu, vector + i, irqs[i]); 462 free(mirqs, M_MSI); 463 return (error); 464 } 465 for (i = 0; i < count; i++) { 466 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]); 467 msi->msi_remap_cookie = cookies[i]; 468 } 469 #endif 470 471 /* Assign IDT vectors and make these messages owned by 'dev'. */ 472 fsrc = (struct msi_intsrc *)intr_lookup_source(irqs[0]); 473 for (i = 0; i < count; i++) { 474 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]); 475 msi->msi_cpu = cpu; 476 msi->msi_dev = dev; 477 msi->msi_vector = vector + i; 478 if (bootverbose) 479 printf( 480 "msi: routing MSI IRQ %d to local APIC %u vector %u\n", 481 msi->msi_irq, msi->msi_cpu, msi->msi_vector); 482 msi->msi_first = fsrc; 483 KASSERT(msi->msi_intsrc.is_handlers == 0, 484 ("dead MSI has handlers")); 485 } 486 fsrc->msi_count = count; 487 fsrc->msi_maxcount = maxcount; 488 if (count > 1) 489 bcopy(irqs, mirqs, count * sizeof(*mirqs)); 490 fsrc->msi_irqs = mirqs; 491 mtx_unlock(&msi_lock); 492 return (0); 493 } 494 495 int 496 msi_release(int *irqs, int count) 497 { 498 struct msi_intsrc *msi, *first; 499 int i; 500 501 mtx_lock(&msi_lock); 502 first = (struct msi_intsrc *)intr_lookup_source(irqs[0]); 503 if (first == NULL) { 504 mtx_unlock(&msi_lock); 505 return (ENOENT); 506 } 507 508 /* Make sure this isn't an MSI-X message. */ 509 if (first->msi_msix) { 510 mtx_unlock(&msi_lock); 511 return (EINVAL); 512 } 513 514 /* Make sure this message is allocated to a group. */ 515 if (first->msi_first == NULL) { 516 mtx_unlock(&msi_lock); 517 return (ENXIO); 518 } 519 520 /* 521 * Make sure this is the start of a group and that we are releasing 522 * the entire group. 523 */ 524 if (first->msi_first != first || first->msi_count != count) { 525 mtx_unlock(&msi_lock); 526 return (EINVAL); 527 } 528 KASSERT(first->msi_dev != NULL, ("unowned group")); 529 530 /* Clear all the extra messages in the group. */ 531 for (i = 1; i < count; i++) { 532 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]); 533 KASSERT(msi->msi_first == first, ("message not in group")); 534 KASSERT(msi->msi_dev == first->msi_dev, ("owner mismatch")); 535 #ifdef IOMMU 536 iommu_unmap_msi_intr(first->msi_dev, msi->msi_remap_cookie); 537 #endif 538 msi->msi_first = NULL; 539 msi->msi_dev = NULL; 540 apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq); 541 msi->msi_vector = 0; 542 } 543 544 /* Clear out the first message. */ 545 #ifdef IOMMU 546 mtx_unlock(&msi_lock); 547 iommu_unmap_msi_intr(first->msi_dev, first->msi_remap_cookie); 548 mtx_lock(&msi_lock); 549 #endif 550 first->msi_first = NULL; 551 first->msi_dev = NULL; 552 apic_free_vector(first->msi_cpu, first->msi_vector, first->msi_irq); 553 first->msi_vector = 0; 554 first->msi_count = 0; 555 first->msi_maxcount = 0; 556 free(first->msi_irqs, M_MSI); 557 first->msi_irqs = NULL; 558 559 mtx_unlock(&msi_lock); 560 return (0); 561 } 562 563 int 564 msi_map(int irq, uint64_t *addr, uint32_t *data) 565 { 566 struct msi_intsrc *msi; 567 int error; 568 #ifdef IOMMU 569 struct msi_intsrc *msi1; 570 int i, k; 571 #endif 572 573 mtx_lock(&msi_lock); 574 msi = (struct msi_intsrc *)intr_lookup_source(irq); 575 if (msi == NULL) { 576 mtx_unlock(&msi_lock); 577 return (ENOENT); 578 } 579 580 /* Make sure this message is allocated to a device. */ 581 if (msi->msi_dev == NULL) { 582 mtx_unlock(&msi_lock); 583 return (ENXIO); 584 } 585 586 /* 587 * If this message isn't an MSI-X message, make sure it's part 588 * of a group, and switch to the first message in the 589 * group. 590 */ 591 if (!msi->msi_msix) { 592 if (msi->msi_first == NULL) { 593 mtx_unlock(&msi_lock); 594 return (ENXIO); 595 } 596 msi = msi->msi_first; 597 } 598 599 #ifdef IOMMU 600 if (!msi->msi_msix) { 601 for (k = msi->msi_count - 1, i = first_msi_irq; k > 0 && 602 i < first_msi_irq + num_msi_irqs; i++) { 603 if (i == msi->msi_irq) 604 continue; 605 msi1 = (struct msi_intsrc *)intr_lookup_source(i); 606 if (!msi1->msi_msix && msi1->msi_first == msi) { 607 mtx_unlock(&msi_lock); 608 iommu_map_msi_intr(msi1->msi_dev, 609 msi1->msi_cpu, msi1->msi_vector, 610 msi1->msi_remap_cookie, NULL, NULL); 611 k--; 612 mtx_lock(&msi_lock); 613 } 614 } 615 } 616 mtx_unlock(&msi_lock); 617 error = iommu_map_msi_intr(msi->msi_dev, msi->msi_cpu, 618 msi->msi_vector, msi->msi_remap_cookie, addr, data); 619 #else 620 mtx_unlock(&msi_lock); 621 error = EOPNOTSUPP; 622 #endif 623 if (error == EOPNOTSUPP) { 624 *addr = INTEL_ADDR(msi); 625 *data = INTEL_DATA(msi); 626 error = 0; 627 } 628 return (error); 629 } 630 631 int 632 msix_alloc(device_t dev, int *irq) 633 { 634 struct msi_intsrc *msi; 635 u_int cpu, domain; 636 int i, vector; 637 #ifdef IOMMU 638 u_int cookie; 639 int error; 640 #endif 641 642 if (!msi_enabled) 643 return (ENXIO); 644 645 if (bus_get_domain(dev, &domain) != 0) 646 domain = 0; 647 648 again: 649 mtx_lock(&msi_lock); 650 651 /* Find a free IRQ. */ 652 for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) { 653 msi = (struct msi_intsrc *)intr_lookup_source(i); 654 655 /* End of allocated sources, so break. */ 656 if (msi == NULL) 657 break; 658 659 /* Stop at the first free source. */ 660 if (msi->msi_dev == NULL) 661 break; 662 } 663 664 /* Are all IRQs in use? */ 665 if (i == first_msi_irq + num_msi_irqs) { 666 mtx_unlock(&msi_lock); 667 return (ENXIO); 668 } 669 670 /* Do we need to create a new source? */ 671 if (msi == NULL) { 672 mtx_unlock(&msi_lock); 673 674 /* Create a new source. */ 675 msi_create_source(); 676 goto again; 677 } 678 679 /* Allocate an IDT vector. */ 680 cpu = intr_next_cpu(domain); 681 vector = apic_alloc_vector(cpu, i); 682 if (vector == 0) { 683 mtx_unlock(&msi_lock); 684 return (ENOSPC); 685 } 686 687 msi->msi_dev = dev; 688 #ifdef IOMMU 689 mtx_unlock(&msi_lock); 690 error = iommu_alloc_msi_intr(dev, &cookie, 1); 691 mtx_lock(&msi_lock); 692 if (error == EOPNOTSUPP) 693 error = 0; 694 if (error != 0) { 695 msi->msi_dev = NULL; 696 apic_free_vector(cpu, vector, i); 697 return (error); 698 } 699 msi->msi_remap_cookie = cookie; 700 #endif 701 702 if (bootverbose) 703 printf("msi: routing MSI-X IRQ %d to local APIC %u vector %u\n", 704 msi->msi_irq, cpu, vector); 705 706 /* Setup source. */ 707 msi->msi_cpu = cpu; 708 msi->msi_first = msi; 709 msi->msi_vector = vector; 710 msi->msi_msix = 1; 711 msi->msi_count = 1; 712 msi->msi_maxcount = 1; 713 msi->msi_irqs = NULL; 714 715 KASSERT(msi->msi_intsrc.is_handlers == 0, ("dead MSI-X has handlers")); 716 mtx_unlock(&msi_lock); 717 718 *irq = i; 719 return (0); 720 } 721 722 int 723 msix_release(int irq) 724 { 725 struct msi_intsrc *msi; 726 727 mtx_lock(&msi_lock); 728 msi = (struct msi_intsrc *)intr_lookup_source(irq); 729 if (msi == NULL) { 730 mtx_unlock(&msi_lock); 731 return (ENOENT); 732 } 733 734 /* Make sure this is an MSI-X message. */ 735 if (!msi->msi_msix) { 736 mtx_unlock(&msi_lock); 737 return (EINVAL); 738 } 739 740 KASSERT(msi->msi_dev != NULL, ("unowned message")); 741 742 /* Clear out the message. */ 743 #ifdef IOMMU 744 mtx_unlock(&msi_lock); 745 iommu_unmap_msi_intr(msi->msi_dev, msi->msi_remap_cookie); 746 mtx_lock(&msi_lock); 747 #endif 748 msi->msi_first = NULL; 749 msi->msi_dev = NULL; 750 apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq); 751 msi->msi_vector = 0; 752 msi->msi_msix = 0; 753 msi->msi_count = 0; 754 msi->msi_maxcount = 0; 755 756 mtx_unlock(&msi_lock); 757 return (0); 758 } 759