1 /*- 2 * Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.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 unmodified, this list of conditions, and the following 10 * 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 ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/dev/virtio/pci/virtio_pci.c,v 1.3 2012/04/14 05:48:04 grehan Exp $ 27 */ 28 29 /* Driver for the VirtIO PCI interface. */ 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/bus.h> 34 #include <sys/kernel.h> 35 #include <sys/module.h> 36 #include <sys/malloc.h> 37 #include <sys/serialize.h> 38 39 #include <bus/pci/pcivar.h> 40 #include <bus/pci/pcireg.h> 41 42 #include <sys/rman.h> 43 44 #include <dev/virtual/virtio/virtio/virtio.h> 45 #include <dev/virtual/virtio/virtio/virtqueue.h> 46 #include "virtio_pci.h" 47 #include "virtio_if.h" 48 #include "virtio_bus_if.h" 49 50 struct vtpci_softc { 51 device_t vtpci_dev; 52 struct resource *vtpci_res; 53 struct resource *vtpci_msix_res; 54 uint64_t vtpci_features; 55 uint32_t vtpci_flags; 56 int vtpci_irq_type; 57 int vtpci_irq_rid; 58 #define VIRTIO_PCI_FLAG_NO_MSI 0x0001 59 #define VIRTIO_PCI_FLAG_MSI 0x0002 60 #define VIRTIO_PCI_FLAG_NO_MSIX 0x0010 61 #define VIRTIO_PCI_FLAG_MSIX 0x0020 62 #define VIRTIO_PCI_FLAG_SHARED_MSIX 0x0040 63 64 device_t vtpci_child_dev; 65 struct virtio_feature_desc *vtpci_child_feat_desc; 66 67 /* 68 * Ideally, each virtqueue that the driver provides a callback for 69 * will receive its own MSIX vector. If there are not sufficient 70 * vectors available, we will then attempt to have all the VQs 71 * share one vector. Note that when using MSIX, the configuration 72 * changed notifications must be on their own vector. 73 * 74 * If MSIX is not available, we will attempt to have the whole 75 * device share one MSI vector, and then, finally, one legacy 76 * interrupt. 77 */ 78 int vtpci_nvqs; 79 struct vtpci_virtqueue { 80 struct virtqueue *vq; 81 82 /* Index into vtpci_intr_res[] below. Unused, then -1. */ 83 int ires_idx; 84 } vtpci_vqx[VIRTIO_MAX_VIRTQUEUES]; 85 86 /* 87 * When using MSIX interrupts, the first element of vtpci_intr_res[] 88 * is always the configuration changed notifications. The remaining 89 * element(s) are used for the virtqueues. 90 * 91 * With MSI and legacy interrupts, only the first element of 92 * vtpci_intr_res[] is used. 93 */ 94 int vtpci_nintr_res; 95 struct vtpci_intr_resource { 96 struct resource *irq; 97 int rid; 98 void *intrhand; 99 } vtpci_intr_res[1 + VIRTIO_MAX_VIRTQUEUES]; 100 }; 101 102 static int vtpci_probe(device_t); 103 static int vtpci_attach(device_t); 104 static int vtpci_detach(device_t); 105 static int vtpci_suspend(device_t); 106 static int vtpci_resume(device_t); 107 static int vtpci_shutdown(device_t); 108 static void vtpci_driver_added(device_t, driver_t *); 109 static void vtpci_child_detached(device_t, device_t); 110 static int vtpci_read_ivar(device_t, device_t, int, uintptr_t *); 111 static int vtpci_write_ivar(device_t, device_t, int, uintptr_t); 112 113 static uint64_t vtpci_negotiate_features(device_t, uint64_t); 114 static int vtpci_with_feature(device_t, uint64_t); 115 static int vtpci_alloc_virtqueues(device_t, int, int, 116 struct vq_alloc_info *); 117 static int vtpci_setup_intr(device_t, lwkt_serialize_t); 118 static void vtpci_stop(device_t); 119 static int vtpci_reinit(device_t, uint64_t); 120 static void vtpci_reinit_complete(device_t); 121 static void vtpci_notify_virtqueue(device_t, uint16_t); 122 static uint8_t vtpci_get_status(device_t); 123 static void vtpci_set_status(device_t, uint8_t); 124 static void vtpci_read_dev_config(device_t, bus_size_t, void *, int); 125 static void vtpci_write_dev_config(device_t, bus_size_t, void *, int); 126 127 static void vtpci_describe_features(struct vtpci_softc *, const char *, 128 uint64_t); 129 static void vtpci_probe_and_attach_child(struct vtpci_softc *); 130 131 static int vtpci_alloc_interrupts(struct vtpci_softc *, int, int, 132 struct vq_alloc_info *); 133 static int vtpci_alloc_intr_resources(struct vtpci_softc *, int, 134 struct vq_alloc_info *); 135 static int vtpci_alloc_msi(struct vtpci_softc *); 136 static int vtpci_alloc_msix(struct vtpci_softc *, int); 137 static int vtpci_register_msix_vector(struct vtpci_softc *, int, int); 138 139 static void vtpci_free_interrupts(struct vtpci_softc *); 140 static void vtpci_free_virtqueues(struct vtpci_softc *); 141 static void vtpci_release_child_resources(struct vtpci_softc *); 142 static void vtpci_reset(struct vtpci_softc *); 143 144 static int vtpci_legacy_intr(void *); 145 static int vtpci_vq_shared_intr(void *); 146 static int vtpci_vq_intr(void *); 147 static int vtpci_config_intr(void *); 148 149 /* 150 * I/O port read/write wrappers. 151 */ 152 #define vtpci_read_config_1(sc, o) bus_read_1((sc)->vtpci_res, (o)) 153 #define vtpci_read_config_2(sc, o) bus_read_2((sc)->vtpci_res, (o)) 154 #define vtpci_read_config_4(sc, o) bus_read_4((sc)->vtpci_res, (o)) 155 #define vtpci_write_config_1(sc, o, v) bus_write_1((sc)->vtpci_res, (o), (v)) 156 #define vtpci_write_config_2(sc, o, v) bus_write_2((sc)->vtpci_res, (o), (v)) 157 #define vtpci_write_config_4(sc, o, v) bus_write_4((sc)->vtpci_res, (o), (v)) 158 159 /* Tunables. */ 160 static int vtpci_disable_msix = 0; 161 TUNABLE_INT("hw.virtio.pci.disable_msix", &vtpci_disable_msix); 162 163 static device_method_t vtpci_methods[] = { 164 /* Device interface. */ 165 DEVMETHOD(device_probe, vtpci_probe), 166 DEVMETHOD(device_attach, vtpci_attach), 167 DEVMETHOD(device_detach, vtpci_detach), 168 DEVMETHOD(device_suspend, vtpci_suspend), 169 DEVMETHOD(device_resume, vtpci_resume), 170 DEVMETHOD(device_shutdown, vtpci_shutdown), 171 172 /* Bus interface. */ 173 DEVMETHOD(bus_driver_added, vtpci_driver_added), 174 DEVMETHOD(bus_child_detached, vtpci_child_detached), 175 DEVMETHOD(bus_read_ivar, vtpci_read_ivar), 176 DEVMETHOD(bus_write_ivar, vtpci_write_ivar), 177 178 /* VirtIO bus interface. */ 179 DEVMETHOD(virtio_bus_negotiate_features, vtpci_negotiate_features), 180 DEVMETHOD(virtio_bus_with_feature, vtpci_with_feature), 181 DEVMETHOD(virtio_bus_alloc_virtqueues, vtpci_alloc_virtqueues), 182 DEVMETHOD(virtio_bus_setup_intr, vtpci_setup_intr), 183 DEVMETHOD(virtio_bus_stop, vtpci_stop), 184 DEVMETHOD(virtio_bus_reinit, vtpci_reinit), 185 DEVMETHOD(virtio_bus_reinit_complete, vtpci_reinit_complete), 186 DEVMETHOD(virtio_bus_notify_vq, vtpci_notify_virtqueue), 187 DEVMETHOD(virtio_bus_read_device_config, vtpci_read_dev_config), 188 DEVMETHOD(virtio_bus_write_device_config, vtpci_write_dev_config), 189 190 DEVMETHOD_END 191 }; 192 193 static driver_t vtpci_driver = { 194 "virtio_pci", 195 vtpci_methods, 196 sizeof(struct vtpci_softc) 197 }; 198 199 devclass_t vtpci_devclass; 200 201 DRIVER_MODULE(virtio_pci, pci, vtpci_driver, vtpci_devclass, NULL, NULL); 202 MODULE_VERSION(virtio_pci, 1); 203 MODULE_DEPEND(virtio_pci, pci, 1, 1, 1); 204 MODULE_DEPEND(virtio_pci, virtio, 1, 1, 1); 205 206 static int 207 vtpci_probe(device_t dev) 208 { 209 char desc[36]; 210 const char *name; 211 212 if (pci_get_vendor(dev) != VIRTIO_PCI_VENDORID) 213 return (ENXIO); 214 215 if (pci_get_device(dev) < VIRTIO_PCI_DEVICEID_MIN || 216 pci_get_device(dev) > VIRTIO_PCI_DEVICEID_MAX) 217 return (ENXIO); 218 219 if (pci_get_revid(dev) != VIRTIO_PCI_ABI_VERSION) 220 return (ENXIO); 221 222 name = virtio_device_name(pci_get_subdevice(dev)); 223 if (name == NULL) 224 name = "Unknown"; 225 226 ksnprintf(desc, sizeof(desc), "VirtIO PCI %s adapter", name); 227 device_set_desc_copy(dev, desc); 228 229 return (BUS_PROBE_DEFAULT); 230 } 231 232 static int 233 vtpci_attach(device_t dev) 234 { 235 struct vtpci_softc *sc; 236 device_t child; 237 int rid; 238 239 sc = device_get_softc(dev); 240 sc->vtpci_dev = dev; 241 242 pci_enable_busmaster(dev); 243 244 rid = PCIR_BAR(0); 245 sc->vtpci_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid, 246 RF_ACTIVE); 247 if (sc->vtpci_res == NULL) { 248 device_printf(dev, "cannot map I/O space\n"); 249 return (ENXIO); 250 } 251 252 if (pci_find_extcap(dev, PCIY_MSI, NULL) != 0) 253 sc->vtpci_flags |= VIRTIO_PCI_FLAG_NO_MSI; 254 #if 0 /* XXX(vsrinivas): Check out how to get MSI-X */ 255 if (pci_find_extcap(dev, PCIY_MSIX, NULL) == 0) { 256 rid = PCIR_BAR(1); 257 sc->vtpci_msix_res = bus_alloc_resource_any(dev, 258 SYS_RES_MEMORY, &rid, RF_ACTIVE); 259 } 260 #endif 261 if (sc->vtpci_msix_res == NULL) 262 sc->vtpci_flags |= VIRTIO_PCI_FLAG_NO_MSIX; 263 264 vtpci_reset(sc); 265 266 /* Tell the host we've noticed this device. */ 267 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_ACK); 268 269 if ((child = device_add_child(dev, NULL, -1)) == NULL) { 270 device_printf(dev, "cannot create child device\n"); 271 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_FAILED); 272 vtpci_detach(dev); 273 return (ENOMEM); 274 } 275 276 sc->vtpci_child_dev = child; 277 vtpci_probe_and_attach_child(sc); 278 279 return (0); 280 } 281 282 static int 283 vtpci_detach(device_t dev) 284 { 285 struct vtpci_softc *sc; 286 device_t child; 287 int error; 288 289 sc = device_get_softc(dev); 290 291 if ((child = sc->vtpci_child_dev) != NULL) { 292 error = device_delete_child(dev, child); 293 if (error) 294 return (error); 295 sc->vtpci_child_dev = NULL; 296 } 297 298 vtpci_reset(sc); 299 300 if (sc->vtpci_msix_res != NULL) { 301 bus_release_resource(dev, SYS_RES_MEMORY, PCIR_BAR(1), 302 sc->vtpci_msix_res); 303 sc->vtpci_msix_res = NULL; 304 } 305 306 if (sc->vtpci_res != NULL) { 307 bus_release_resource(dev, SYS_RES_IOPORT, PCIR_BAR(0), 308 sc->vtpci_res); 309 sc->vtpci_res = NULL; 310 } 311 312 return (0); 313 } 314 315 static int 316 vtpci_suspend(device_t dev) 317 { 318 319 return (bus_generic_suspend(dev)); 320 } 321 322 static int 323 vtpci_resume(device_t dev) 324 { 325 326 return (bus_generic_resume(dev)); 327 } 328 329 static int 330 vtpci_shutdown(device_t dev) 331 { 332 333 (void) bus_generic_shutdown(dev); 334 /* Forcibly stop the host device. */ 335 vtpci_stop(dev); 336 337 return (0); 338 } 339 340 static void 341 vtpci_driver_added(device_t dev, driver_t *driver) 342 { 343 struct vtpci_softc *sc; 344 345 sc = device_get_softc(dev); 346 347 vtpci_probe_and_attach_child(sc); 348 } 349 350 static void 351 vtpci_child_detached(device_t dev, device_t child) 352 { 353 struct vtpci_softc *sc; 354 355 sc = device_get_softc(dev); 356 357 vtpci_reset(sc); 358 vtpci_release_child_resources(sc); 359 } 360 361 static int 362 vtpci_read_ivar(device_t dev, device_t child, int index, uintptr_t *result) 363 { 364 struct vtpci_softc *sc; 365 366 sc = device_get_softc(dev); 367 368 if (sc->vtpci_child_dev != child) 369 return (ENOENT); 370 371 switch (index) { 372 case VIRTIO_IVAR_DEVTYPE: 373 *result = pci_get_subdevice(dev); 374 break; 375 default: 376 return (ENOENT); 377 } 378 379 return (0); 380 } 381 382 static int 383 vtpci_write_ivar(device_t dev, device_t child, int index, uintptr_t value) 384 { 385 struct vtpci_softc *sc; 386 387 sc = device_get_softc(dev); 388 389 if (sc->vtpci_child_dev != child) 390 return (ENOENT); 391 392 switch (index) { 393 case VIRTIO_IVAR_FEATURE_DESC: 394 sc->vtpci_child_feat_desc = (void *) value; 395 break; 396 default: 397 return (ENOENT); 398 } 399 400 return (0); 401 } 402 403 static uint64_t 404 vtpci_negotiate_features(device_t dev, uint64_t child_features) 405 { 406 struct vtpci_softc *sc; 407 uint64_t host_features, features; 408 409 sc = device_get_softc(dev); 410 411 host_features = vtpci_read_config_4(sc, VIRTIO_PCI_HOST_FEATURES); 412 vtpci_describe_features(sc, "host", host_features); 413 414 /* 415 * Limit negotiated features to what the driver, virtqueue, and 416 * host all support. 417 */ 418 features = host_features & child_features; 419 features = virtqueue_filter_features(features); 420 sc->vtpci_features = features; 421 422 vtpci_describe_features(sc, "negotiated", features); 423 vtpci_write_config_4(sc, VIRTIO_PCI_GUEST_FEATURES, features); 424 425 return (features); 426 } 427 428 static int 429 vtpci_with_feature(device_t dev, uint64_t feature) 430 { 431 struct vtpci_softc *sc; 432 433 sc = device_get_softc(dev); 434 435 return ((sc->vtpci_features & feature) != 0); 436 } 437 438 static int 439 vtpci_alloc_virtqueues(device_t dev, int flags, int nvqs, 440 struct vq_alloc_info *vq_info) 441 { 442 struct vtpci_softc *sc; 443 struct vtpci_virtqueue *vqx; 444 struct vq_alloc_info *info; 445 int queue, error; 446 uint16_t vq_size; 447 448 sc = device_get_softc(dev); 449 450 if (sc->vtpci_nvqs != 0 || nvqs <= 0 || 451 nvqs > VIRTIO_MAX_VIRTQUEUES) 452 return (EINVAL); 453 454 error = vtpci_alloc_interrupts(sc, flags, nvqs, vq_info); 455 if (error) { 456 device_printf(dev, "cannot allocate interrupts\n"); 457 return (error); 458 } 459 460 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) { 461 error = vtpci_register_msix_vector(sc, 462 VIRTIO_MSI_CONFIG_VECTOR, 0); 463 if (error) 464 return (error); 465 } 466 467 for (queue = 0; queue < nvqs; queue++) { 468 vqx = &sc->vtpci_vqx[queue]; 469 info = &vq_info[queue]; 470 471 vtpci_write_config_2(sc, VIRTIO_PCI_QUEUE_SEL, queue); 472 473 vq_size = vtpci_read_config_2(sc, VIRTIO_PCI_QUEUE_NUM); 474 error = virtqueue_alloc(dev, queue, vq_size, 475 VIRTIO_PCI_VRING_ALIGN, 0xFFFFFFFFUL, info, &vqx->vq); 476 if (error) 477 return (error); 478 479 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) { 480 error = vtpci_register_msix_vector(sc, 481 VIRTIO_MSI_QUEUE_VECTOR, vqx->ires_idx); 482 if (error) 483 return (error); 484 } 485 486 vtpci_write_config_4(sc, VIRTIO_PCI_QUEUE_PFN, 487 virtqueue_paddr(vqx->vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT); 488 489 *info->vqai_vq = vqx->vq; 490 sc->vtpci_nvqs++; 491 } 492 493 return (0); 494 } 495 496 static int 497 vtpci_setup_intr(device_t dev, lwkt_serialize_t slz) 498 { 499 struct vtpci_softc *sc; 500 struct vtpci_intr_resource *ires; 501 struct vtpci_virtqueue *vqx; 502 int i, flags, error; 503 504 sc = device_get_softc(dev); 505 flags = INTR_MPSAFE; 506 ires = &sc->vtpci_intr_res[0]; 507 508 if ((sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) == 0) { 509 error = bus_setup_intr(dev, ires->irq, flags, 510 (driver_intr_t *) vtpci_legacy_intr, 511 sc, &ires->intrhand, slz); 512 return (error); 513 } 514 515 error = bus_setup_intr(dev, ires->irq, flags, 516 (driver_intr_t *) vtpci_config_intr, 517 sc, &ires->intrhand, slz); 518 if (error) 519 return (error); 520 521 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_SHARED_MSIX) { 522 ires = &sc->vtpci_intr_res[1]; 523 error = bus_setup_intr(dev, ires->irq, flags, 524 (driver_intr_t *) vtpci_vq_shared_intr, 525 sc, &ires->intrhand, slz); 526 527 return (error); 528 } 529 530 /* Setup an interrupt handler for each virtqueue. */ 531 for (i = 0; i < sc->vtpci_nvqs; i++) { 532 vqx = &sc->vtpci_vqx[i]; 533 if (vqx->ires_idx < 1) 534 continue; 535 536 ires = &sc->vtpci_intr_res[vqx->ires_idx]; 537 error = bus_setup_intr(dev, ires->irq, flags, 538 (driver_intr_t *) vtpci_vq_intr, 539 vqx->vq, &ires->intrhand, slz); 540 if (error) 541 return (error); 542 } 543 544 return (0); 545 } 546 547 static void 548 vtpci_stop(device_t dev) 549 { 550 vtpci_reset(device_get_softc(dev)); 551 } 552 553 static int 554 vtpci_reinit(device_t dev, uint64_t features) 555 { 556 struct vtpci_softc *sc; 557 struct vtpci_virtqueue *vqx; 558 struct virtqueue *vq; 559 int queue, error; 560 uint16_t vq_size; 561 562 sc = device_get_softc(dev); 563 564 /* 565 * Redrive the device initialization. This is a bit of an abuse 566 * of the specification, but both VirtualBox and QEMU/KVM seem 567 * to play nice. We do not allow the host device to change from 568 * what was originally negotiated beyond what the guest driver 569 * changed (MSIX state should not change, number of virtqueues 570 * and their size remain the same, etc). 571 */ 572 573 if (vtpci_get_status(dev) != VIRTIO_CONFIG_STATUS_RESET) 574 vtpci_stop(dev); 575 576 /* 577 * Quickly drive the status through ACK and DRIVER. The device 578 * does not become usable again until vtpci_reinit_complete(). 579 */ 580 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_ACK); 581 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER); 582 583 vtpci_negotiate_features(dev, features); 584 585 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) { 586 error = vtpci_register_msix_vector(sc, 587 VIRTIO_MSI_CONFIG_VECTOR, 0); 588 if (error) 589 return (error); 590 } 591 592 for (queue = 0; queue < sc->vtpci_nvqs; queue++) { 593 vqx = &sc->vtpci_vqx[queue]; 594 vq = vqx->vq; 595 596 KASSERT(vq != NULL, ("vq %d not allocated", queue)); 597 vtpci_write_config_2(sc, VIRTIO_PCI_QUEUE_SEL, queue); 598 599 vq_size = vtpci_read_config_2(sc, VIRTIO_PCI_QUEUE_NUM); 600 error = virtqueue_reinit(vq, vq_size); 601 if (error) 602 return (error); 603 604 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) { 605 error = vtpci_register_msix_vector(sc, 606 VIRTIO_MSI_QUEUE_VECTOR, vqx->ires_idx); 607 if (error) 608 return (error); 609 } 610 611 vtpci_write_config_4(sc, VIRTIO_PCI_QUEUE_PFN, 612 virtqueue_paddr(vqx->vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT); 613 } 614 615 return (0); 616 } 617 618 static void 619 vtpci_reinit_complete(device_t dev) 620 { 621 622 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER_OK); 623 } 624 625 static void 626 vtpci_notify_virtqueue(device_t dev, uint16_t queue) 627 { 628 struct vtpci_softc *sc; 629 630 sc = device_get_softc(dev); 631 632 vtpci_write_config_2(sc, VIRTIO_PCI_QUEUE_NOTIFY, queue); 633 } 634 635 static uint8_t 636 vtpci_get_status(device_t dev) 637 { 638 struct vtpci_softc *sc; 639 640 sc = device_get_softc(dev); 641 642 return (vtpci_read_config_1(sc, VIRTIO_PCI_STATUS)); 643 } 644 645 static void 646 vtpci_set_status(device_t dev, uint8_t status) 647 { 648 struct vtpci_softc *sc; 649 650 sc = device_get_softc(dev); 651 652 if (status != VIRTIO_CONFIG_STATUS_RESET) 653 status |= vtpci_get_status(dev); 654 655 vtpci_write_config_1(sc, VIRTIO_PCI_STATUS, status); 656 } 657 658 static void 659 vtpci_read_dev_config(device_t dev, bus_size_t offset, 660 void *dst, int length) 661 { 662 struct vtpci_softc *sc; 663 bus_size_t off; 664 uint8_t *d; 665 int size; 666 667 sc = device_get_softc(dev); 668 off = VIRTIO_PCI_CONFIG(sc) + offset; 669 670 for (d = dst; length > 0; d += size, off += size, length -= size) { 671 if (length >= 4) { 672 size = 4; 673 *(uint32_t *)d = vtpci_read_config_4(sc, off); 674 } else if (length >= 2) { 675 size = 2; 676 *(uint16_t *)d = vtpci_read_config_2(sc, off); 677 } else { 678 size = 1; 679 *d = vtpci_read_config_1(sc, off); 680 } 681 } 682 } 683 684 static void 685 vtpci_write_dev_config(device_t dev, bus_size_t offset, 686 void *src, int length) 687 { 688 struct vtpci_softc *sc; 689 bus_size_t off; 690 uint8_t *s; 691 int size; 692 693 sc = device_get_softc(dev); 694 off = VIRTIO_PCI_CONFIG(sc) + offset; 695 696 for (s = src; length > 0; s += size, off += size, length -= size) { 697 if (length >= 4) { 698 size = 4; 699 vtpci_write_config_4(sc, off, *(uint32_t *)s); 700 } else if (length >= 2) { 701 size = 2; 702 vtpci_write_config_2(sc, off, *(uint16_t *)s); 703 } else { 704 size = 1; 705 vtpci_write_config_1(sc, off, *s); 706 } 707 } 708 } 709 710 static void 711 vtpci_describe_features(struct vtpci_softc *sc, const char *msg, 712 uint64_t features) 713 { 714 device_t dev, child; 715 716 dev = sc->vtpci_dev; 717 child = sc->vtpci_child_dev; 718 719 if (device_is_attached(child) && bootverbose == 0) 720 return; 721 722 virtio_describe(dev, msg, features, sc->vtpci_child_feat_desc); 723 } 724 725 static void 726 vtpci_probe_and_attach_child(struct vtpci_softc *sc) 727 { 728 device_t dev, child; 729 int error; 730 731 dev = sc->vtpci_dev; 732 child = sc->vtpci_child_dev; 733 734 if (child == NULL) 735 return; 736 737 if (device_get_state(child) != DS_NOTPRESENT) 738 return; 739 740 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER); 741 error = device_probe_and_attach(child); 742 if (error != 0 || device_get_state(child) == DS_NOTPRESENT) { 743 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_FAILED); 744 vtpci_reset(sc); 745 vtpci_release_child_resources(sc); 746 747 /* Reset status for future attempt. */ 748 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_ACK); 749 } else 750 vtpci_set_status(dev, VIRTIO_CONFIG_STATUS_DRIVER_OK); 751 } 752 753 static int 754 vtpci_alloc_interrupts(struct vtpci_softc *sc, int flags, int nvqs, 755 struct vq_alloc_info *vq_info) 756 { 757 int i, nvectors, error; 758 759 /* 760 * Only allocate a vector for virtqueues that are actually 761 * expecting an interrupt. 762 */ 763 for (nvectors = 0, i = 0; i < nvqs; i++) 764 if (vq_info[i].vqai_intr != NULL) 765 nvectors++; 766 767 if (vtpci_disable_msix != 0 || 768 sc->vtpci_flags & VIRTIO_PCI_FLAG_NO_MSIX || 769 flags & VIRTIO_ALLOC_VQS_DISABLE_MSIX || 770 vtpci_alloc_msix(sc, nvectors) != 0) { 771 /* 772 * Use MSI interrupts if available. Otherwise, we fallback 773 * to legacy interrupts. 774 */ 775 if ((sc->vtpci_flags & VIRTIO_PCI_FLAG_NO_MSI) == 0 && 776 vtpci_alloc_msi(sc) == 0) 777 sc->vtpci_flags |= VIRTIO_PCI_FLAG_MSI; 778 779 sc->vtpci_nintr_res = 1; 780 } 781 782 error = vtpci_alloc_intr_resources(sc, nvqs, vq_info); 783 784 return (error); 785 } 786 787 static int 788 vtpci_alloc_intr_resources(struct vtpci_softc *sc, int nvqs, 789 struct vq_alloc_info *vq_info) 790 { 791 device_t dev; 792 struct resource *irq; 793 struct vtpci_virtqueue *vqx; 794 int i, rid, flags, res_idx; 795 796 dev = sc->vtpci_dev; 797 flags = RF_ACTIVE; 798 799 if ((sc->vtpci_flags & 800 (VIRTIO_PCI_FLAG_MSI | VIRTIO_PCI_FLAG_MSIX)) == 0) { 801 rid = 0; 802 flags |= RF_SHAREABLE; 803 } else 804 rid = 1; 805 806 for (i = 0; i < sc->vtpci_nintr_res; i++) { 807 irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, flags); 808 if (irq == NULL) 809 return (ENXIO); 810 811 sc->vtpci_intr_res[i].irq = irq; 812 sc->vtpci_intr_res[i].rid = rid++; 813 } 814 815 /* 816 * Map the virtqueue into the correct index in vq_intr_res[]. Note the 817 * first index is reserved for configuration changes notifications. 818 */ 819 for (i = 0, res_idx = 1; i < nvqs; i++) { 820 vqx = &sc->vtpci_vqx[i]; 821 822 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_MSIX) { 823 if (vq_info[i].vqai_intr == NULL) 824 vqx->ires_idx = -1; 825 else if (sc->vtpci_flags & VIRTIO_PCI_FLAG_SHARED_MSIX) 826 vqx->ires_idx = res_idx; 827 else 828 vqx->ires_idx = res_idx++; 829 } else 830 vqx->ires_idx = -1; 831 } 832 833 return (0); 834 } 835 836 static int 837 vtpci_alloc_msi(struct vtpci_softc *sc) 838 { 839 device_t dev; 840 int nmsi; 841 u_int irq_flags; 842 843 dev = sc->vtpci_dev; 844 nmsi = pci_msi_count(dev); 845 846 if (nmsi < 1) 847 return (1); 848 849 sc->vtpci_irq_rid = 0; 850 sc->vtpci_irq_type = pci_alloc_1intr(dev, 1, 851 &sc->vtpci_irq_rid, &irq_flags); 852 853 854 return (0); 855 } 856 857 static int 858 vtpci_alloc_msix(struct vtpci_softc *sc, int nvectors) 859 { 860 /* XXX(vsrinivas): Huh? Is this how MSI-X works?*/ 861 /* XXX(vsrinivas): All of this was disabled... */ 862 #if 0 863 device_t dev; 864 int nmsix, cnt, required; 865 866 dev = sc->vtpci_dev; 867 868 nmsix = pci_msix_count(dev); 869 if (nmsix < 1) 870 return (1); 871 872 /* An additional vector is needed for the config changes. */ 873 required = nvectors + 1; 874 if (nmsix >= required) { 875 cnt = required; 876 if (pci_alloc_msix(dev, &cnt) == 0 && cnt >= required) 877 goto out; 878 879 pci_release_msi(dev); 880 } 881 882 /* Attempt shared MSIX configuration. */ 883 required = 2; 884 if (nmsix >= required) { 885 cnt = required; 886 if (pci_alloc_msix(dev, &cnt) == 0 && cnt >= required) { 887 sc->vtpci_flags |= VIRTIO_PCI_FLAG_SHARED_MSIX; 888 goto out; 889 } 890 891 pci_release_msi(dev); 892 } 893 894 return (1); 895 896 out: 897 sc->vtpci_nintr_res = required; 898 sc->vtpci_flags |= VIRTIO_PCI_FLAG_MSIX; 899 900 if (bootverbose) { 901 if (sc->vtpci_flags & VIRTIO_PCI_FLAG_SHARED_MSIX) 902 device_printf(dev, "using shared virtqueue MSIX\n"); 903 else 904 device_printf(dev, "using per virtqueue MSIX\n"); 905 } 906 #endif 907 return (0); 908 } 909 910 static int 911 vtpci_register_msix_vector(struct vtpci_softc *sc, int offset, int res_idx) 912 { 913 device_t dev; 914 uint16_t vector; 915 916 dev = sc->vtpci_dev; 917 918 if (offset != VIRTIO_MSI_CONFIG_VECTOR && 919 offset != VIRTIO_MSI_QUEUE_VECTOR) 920 return (EINVAL); 921 922 if (res_idx != -1) { 923 /* Map from rid to host vector. */ 924 vector = sc->vtpci_intr_res[res_idx].rid - 1; 925 } else 926 vector = VIRTIO_MSI_NO_VECTOR; 927 928 /* The first resource is special; make sure it is used correctly. */ 929 if (res_idx == 0) { 930 KASSERT(vector == 0, ("unexpected config vector")); 931 KASSERT(offset == VIRTIO_MSI_CONFIG_VECTOR, 932 ("unexpected config offset")); 933 } 934 935 vtpci_write_config_2(sc, offset, vector); 936 937 if (vtpci_read_config_2(sc, offset) != vector) { 938 device_printf(dev, "insufficient host resources for " 939 "MSIX interrupts\n"); 940 return (ENODEV); 941 } 942 943 return (0); 944 } 945 946 static void 947 vtpci_free_interrupts(struct vtpci_softc *sc) 948 { 949 device_t dev; 950 struct vtpci_intr_resource *ires; 951 int i; 952 953 dev = sc->vtpci_dev; 954 sc->vtpci_nintr_res = 0; 955 956 if (sc->vtpci_flags & (VIRTIO_PCI_FLAG_MSI | VIRTIO_PCI_FLAG_MSIX)) { 957 pci_release_msi(dev); 958 sc->vtpci_flags &= ~(VIRTIO_PCI_FLAG_MSI | 959 VIRTIO_PCI_FLAG_MSIX | VIRTIO_PCI_FLAG_SHARED_MSIX); 960 } 961 962 for (i = 0; i < 1 + VIRTIO_MAX_VIRTQUEUES; i++) { 963 ires = &sc->vtpci_intr_res[i]; 964 965 if (ires->intrhand != NULL) { 966 bus_teardown_intr(dev, ires->irq, ires->intrhand); 967 ires->intrhand = NULL; 968 } 969 970 if (ires->irq != NULL) { 971 bus_release_resource(dev, SYS_RES_IRQ, ires->rid, 972 ires->irq); 973 ires->irq = NULL; 974 } 975 976 ires->rid = -1; 977 } 978 } 979 980 static void 981 vtpci_free_virtqueues(struct vtpci_softc *sc) 982 { 983 struct vtpci_virtqueue *vqx; 984 int i; 985 986 sc->vtpci_nvqs = 0; 987 988 for (i = 0; i < VIRTIO_MAX_VIRTQUEUES; i++) { 989 vqx = &sc->vtpci_vqx[i]; 990 991 if (vqx->vq != NULL) { 992 virtqueue_free(vqx->vq); 993 vqx->vq = NULL; 994 } 995 } 996 } 997 998 static void 999 vtpci_release_child_resources(struct vtpci_softc *sc) 1000 { 1001 1002 vtpci_free_interrupts(sc); 1003 vtpci_free_virtqueues(sc); 1004 } 1005 1006 static void 1007 vtpci_reset(struct vtpci_softc *sc) 1008 { 1009 1010 /* 1011 * Setting the status to RESET sets the host device to 1012 * the original, uninitialized state. 1013 */ 1014 vtpci_set_status(sc->vtpci_dev, VIRTIO_CONFIG_STATUS_RESET); 1015 } 1016 1017 static int 1018 vtpci_legacy_intr(void *xsc) 1019 { 1020 struct vtpci_softc *sc; 1021 struct vtpci_virtqueue *vqx; 1022 int i; 1023 uint8_t isr; 1024 1025 sc = xsc; 1026 vqx = &sc->vtpci_vqx[0]; 1027 1028 /* Reading the ISR also clears it. */ 1029 isr = vtpci_read_config_1(sc, VIRTIO_PCI_ISR); 1030 1031 if (isr & VIRTIO_PCI_ISR_CONFIG) 1032 vtpci_config_intr(sc); 1033 1034 if (isr & VIRTIO_PCI_ISR_INTR) 1035 for (i = 0; i < sc->vtpci_nvqs; i++, vqx++) 1036 virtqueue_intr(vqx->vq); 1037 1038 return isr; 1039 } 1040 1041 static int 1042 vtpci_vq_shared_intr(void *xsc) 1043 { 1044 struct vtpci_softc *sc; 1045 struct vtpci_virtqueue *vqx; 1046 int i, rc; 1047 1048 rc = 0; 1049 sc = xsc; 1050 vqx = &sc->vtpci_vqx[0]; 1051 1052 for (i = 0; i < sc->vtpci_nvqs; i++, vqx++) 1053 rc |= virtqueue_intr(vqx->vq); 1054 1055 return rc; 1056 } 1057 1058 static int 1059 vtpci_vq_intr(void *xvq) 1060 { 1061 struct virtqueue *vq; 1062 int rc; 1063 1064 vq = xvq; 1065 rc = virtqueue_intr(vq); 1066 1067 return rc; 1068 } 1069 1070 static int 1071 vtpci_config_intr(void *xsc) 1072 { 1073 struct vtpci_softc *sc; 1074 device_t child; 1075 int rc; 1076 1077 rc = 0; 1078 sc = xsc; 1079 child = sc->vtpci_child_dev; 1080 1081 if (child != NULL) 1082 rc = VIRTIO_CONFIG_CHANGE(child); 1083 1084 return rc; 1085 } 1086