hw/ppc/spapr_irq.c

   1 /*
   2  * QEMU PowerPC sPAPR IRQ interface
   3  *
   4  * Copyright (c) 2018, IBM Corporation.
   5  *
   6  * This code is licensed under the GPL version 2 or later. See the
   7  * COPYING file in the top-level directory.
   8  */
   9
  10 #include "qemu/osdep.h"
  11 #include "qemu/log.h"
  12 #include "qemu/error-report.h"
  13 #include "qapi/error.h"
  14 #include "hw/irq.h"
  15 #include "hw/ppc/spapr.h"
  16 #include "hw/ppc/spapr_cpu_core.h"
  17 #include "hw/ppc/spapr_xive.h"
  18 #include "hw/ppc/xics.h"
  19 #include "hw/ppc/xics_spapr.h"
  20 #include "hw/qdev-properties.h"
  21 #include "cpu-models.h"
  22 #include "sysemu/kvm.h"
  23
  24 #include "trace.h"
  25
  26 static const TypeInfo spapr_intc_info = {
  27     .name = TYPE_SPAPR_INTC,
  28     .parent = TYPE_INTERFACE,
  29     .class_size = sizeof(SpaprInterruptControllerClass),
  30 };
  31
  32 static void spapr_irq_msi_init(SpaprMachineState *spapr)
  33 {
  34     if (SPAPR_MACHINE_GET_CLASS(spapr)->legacy_irq_allocation) {
  35         /* Legacy mode doesn't use this allocator */
  36         return;
  37     }
  38
  39     spapr->irq_map_nr = spapr_irq_nr_msis(spapr);
  40     spapr->irq_map = bitmap_new(spapr->irq_map_nr);
  41 }
  42
  43 int spapr_irq_msi_alloc(SpaprMachineState *spapr, uint32_t num, bool align,
  44                         Error **errp)
  45 {
  46     int irq;
  47
  48     /*
  49      * The 'align_mask' parameter of bitmap_find_next_zero_area()
  50      * should be one less than a power of 2; 0 means no
  51      * alignment. Adapt the 'align' value of the former allocator
  52      * to fit the requirements of bitmap_find_next_zero_area()
  53      */
  54     align -= 1;
  55
  56     irq = bitmap_find_next_zero_area(spapr->irq_map, spapr->irq_map_nr, 0, num,
  57                                      align);
  58     if (irq == spapr->irq_map_nr) {
  59         error_setg(errp, "can't find a free %d-IRQ block", num);
  60         return -1;
  61     }
  62
  63     bitmap_set(spapr->irq_map, irq, num);
  64
  65     return irq + SPAPR_IRQ_MSI;
  66 }
  67
  68 void spapr_irq_msi_free(SpaprMachineState *spapr, int irq, uint32_t num)
  69 {
  70     bitmap_clear(spapr->irq_map, irq - SPAPR_IRQ_MSI, num);
  71 }
  72
  73 int spapr_irq_init_kvm(SpaprInterruptControllerInitKvm fn,
  74                        SpaprInterruptController *intc,
  75                        uint32_t nr_servers,
  76                        Error **errp)
  77 {
  78     Error *local_err = NULL;
  79
  80     if (kvm_enabled() && kvm_kernel_irqchip_allowed()) {
  81         if (fn(intc, nr_servers, &local_err) < 0) {
  82             if (kvm_kernel_irqchip_required()) {
  83                 error_prepend(&local_err,
  84                               "kernel_irqchip requested but unavailable: ");
  85                 error_propagate(errp, local_err);
  86                 return -1;
  87             }
  88
  89             /*
  90              * We failed to initialize the KVM device, fallback to
  91              * emulated mode
  92              */
  93             error_prepend(&local_err,
  94                           "kernel_irqchip allowed but unavailable: ");
  95             error_append_hint(&local_err,
  96                               "Falling back to kernel-irqchip=off\n");
  97             warn_report_err(local_err);
  98         }
  99     }
 100
 101     return 0;
 102 }
 103
 104 /*
 105  * XICS IRQ backend.
 106  */
 107
 108 SpaprIrq spapr_irq_xics = {
 109     .xics        = true,
 110     .xive        = false,
 111 };
 112
 113 /*
 114  * XIVE IRQ backend.
 115  */
 116
 117 SpaprIrq spapr_irq_xive = {
 118     .xics        = false,
 119     .xive        = true,
 120 };
 121
 122 /*
 123  * Dual XIVE and XICS IRQ backend.
 124  *
 125  * Both interrupt mode, XIVE and XICS, objects are created but the
 126  * machine starts in legacy interrupt mode (XICS). It can be changed
 127  * by the CAS negotiation process and, in that case, the new mode is
 128  * activated after an extra machine reset.
 129  */
 130
 131 /*
 132  * Define values in sync with the XIVE and XICS backend
 133  */
 134 SpaprIrq spapr_irq_dual = {
 135     .xics        = true,
 136     .xive        = true,
 137 };
 138
 139
 140 static int spapr_irq_check(SpaprMachineState *spapr, Error **errp)
 141 {
 142     MachineState *machine = MACHINE(spapr);
 143
 144     /*
 145      * Sanity checks on non-P9 machines. On these, XIVE is not
 146      * advertised, see spapr_dt_ov5_platform_support()
 147      */
 148     if (!ppc_type_check_compat(machine->cpu_type, CPU_POWERPC_LOGICAL_3_00,
 149                                0, spapr->max_compat_pvr)) {
 150         /*
 151          * If the 'dual' interrupt mode is selected, force XICS as CAS
 152          * negotiation is useless.
 153          */
 154         if (spapr->irq == &spapr_irq_dual) {
 155             spapr->irq = &spapr_irq_xics;
 156             return 0;
 157         }
 158
 159         /*
 160          * Non-P9 machines using only XIVE is a bogus setup. We have two
 161          * scenarios to take into account because of the compat mode:
 162          *
 163          * 1. POWER7/8 machines should fail to init later on when creating
 164          *    the XIVE interrupt presenters because a POWER9 exception
 165          *    model is required.
 166
 167          * 2. POWER9 machines using the POWER8 compat mode won't fail and
 168          *    will let the OS boot with a partial XIVE setup : DT
 169          *    properties but no hcalls.
 170          *
 171          * To cover both and not confuse the OS, add an early failure in
 172          * QEMU.
 173          */
 174         if (spapr->irq == &spapr_irq_xive) {
 175             error_setg(errp, "XIVE-only machines require a POWER9 CPU");
 176             return -1;
 177         }
 178     }
 179
 180     /*
 181      * On a POWER9 host, some older KVM XICS devices cannot be destroyed and
 182      * re-created. Detect that early to avoid QEMU to exit later when the
 183      * guest reboots.
 184      */
 185     if (kvm_enabled() &&
 186         spapr->irq == &spapr_irq_dual &&
 187         kvm_kernel_irqchip_required() &&
 188         xics_kvm_has_broken_disconnect(spapr)) {
 189         error_setg(errp, "KVM is too old to support ic-mode=dual,kernel-irqchip=on");
 190         return -1;
 191     }
 192
 193     return 0;
 194 }
 195
 196 /*
 197  * sPAPR IRQ frontend routines for devices
 198  */
 199 #define ALL_INTCS(spapr_) \
 200     { SPAPR_INTC((spapr_)->ics), SPAPR_INTC((spapr_)->xive), }
 201
 202 int spapr_irq_cpu_intc_create(SpaprMachineState *spapr,
 203                               PowerPCCPU *cpu, Error **errp)
 204 {
 205     SpaprInterruptController *intcs[] = ALL_INTCS(spapr);
 206     int i;
 207     int rc;
 208
 209     for (i = 0; i < ARRAY_SIZE(intcs); i++) {
 210         SpaprInterruptController *intc = intcs[i];
 211         if (intc) {
 212             SpaprInterruptControllerClass *sicc = SPAPR_INTC_GET_CLASS(intc);
 213             rc = sicc->cpu_intc_create(intc, cpu, errp);
 214             if (rc < 0) {
 215                 return rc;
 216             }
 217         }
 218     }
 219
 220     return 0;
 221 }
 222
 223 void spapr_irq_cpu_intc_reset(SpaprMachineState *spapr, PowerPCCPU *cpu)
 224 {
 225     SpaprInterruptController *intcs[] = ALL_INTCS(spapr);
 226     int i;
 227
 228     for (i = 0; i < ARRAY_SIZE(intcs); i++) {
 229         SpaprInterruptController *intc = intcs[i];
 230         if (intc) {
 231             SpaprInterruptControllerClass *sicc = SPAPR_INTC_GET_CLASS(intc);
 232             sicc->cpu_intc_reset(intc, cpu);
 233         }
 234     }
 235 }
 236
 237 void spapr_irq_cpu_intc_destroy(SpaprMachineState *spapr, PowerPCCPU *cpu)
 238 {
 239     SpaprInterruptController *intcs[] = ALL_INTCS(spapr);
 240     int i;
 241
 242     for (i = 0; i < ARRAY_SIZE(intcs); i++) {
 243         SpaprInterruptController *intc = intcs[i];
 244         if (intc) {
 245             SpaprInterruptControllerClass *sicc = SPAPR_INTC_GET_CLASS(intc);
 246             sicc->cpu_intc_destroy(intc, cpu);
 247         }
 248     }
 249 }
 250
 251 static void spapr_set_irq(void *opaque, int irq, int level)
 252 {
 253     SpaprMachineState *spapr = SPAPR_MACHINE(opaque);
 254     SpaprInterruptControllerClass *sicc
 255         = SPAPR_INTC_GET_CLASS(spapr->active_intc);
 256
 257     sicc->set_irq(spapr->active_intc, irq, level);
 258 }
 259
 260 void spapr_irq_print_info(SpaprMachineState *spapr, Monitor *mon)
 261 {
 262     SpaprInterruptControllerClass *sicc
 263         = SPAPR_INTC_GET_CLASS(spapr->active_intc);
 264
 265     sicc->print_info(spapr->active_intc, mon);
 266 }
 267
 268 void spapr_irq_dt(SpaprMachineState *spapr, uint32_t nr_servers,
 269                   void *fdt, uint32_t phandle)
 270 {
 271     SpaprInterruptControllerClass *sicc
 272         = SPAPR_INTC_GET_CLASS(spapr->active_intc);
 273
 274     sicc->dt(spapr->active_intc, nr_servers, fdt, phandle);
 275 }
 276
 277 uint32_t spapr_irq_nr_msis(SpaprMachineState *spapr)
 278 {
 279     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
 280
 281     if (smc->legacy_irq_allocation) {
 282         return smc->nr_xirqs;
 283     } else {
 284         return SPAPR_XIRQ_BASE + smc->nr_xirqs - SPAPR_IRQ_MSI;
 285     }
 286 }
 287
 288 void spapr_irq_init(SpaprMachineState *spapr, Error **errp)
 289 {
 290     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
 291
 292     if (kvm_enabled() && kvm_kernel_irqchip_split()) {
 293         error_setg(errp, "kernel_irqchip split mode not supported on pseries");
 294         return;
 295     }
 296
 297     if (spapr_irq_check(spapr, errp) < 0) {
 298         return;
 299     }
 300
 301     /* Initialize the MSI IRQ allocator. */
 302     spapr_irq_msi_init(spapr);
 303
 304     if (spapr->irq->xics) {
 305         Object *obj;
 306
 307         obj = object_new(TYPE_ICS_SPAPR);
 308
 309         object_property_add_child(OBJECT(spapr), "ics", obj);
 310         object_property_set_link(obj, ICS_PROP_XICS, OBJECT(spapr),
 311                                  &error_abort);
 312         object_property_set_int(obj, "nr-irqs", smc->nr_xirqs, &error_abort);
 313         if (!qdev_realize(DEVICE(obj), NULL, errp)) {
 314             return;
 315         }
 316
 317         spapr->ics = ICS_SPAPR(obj);
 318     }
 319
 320     if (spapr->irq->xive) {
 321         uint32_t nr_servers = spapr_max_server_number(spapr);
 322         DeviceState *dev;
 323         int i;
 324
 325         dev = qdev_new(TYPE_SPAPR_XIVE);
 326         qdev_prop_set_uint32(dev, "nr-irqs", smc->nr_xirqs + SPAPR_XIRQ_BASE);
 327         /*
 328          * 8 XIVE END structures per CPU. One for each available
 329          * priority
 330          */
 331         qdev_prop_set_uint32(dev, "nr-ends", nr_servers << 3);
 332         object_property_set_link(OBJECT(dev), "xive-fabric", OBJECT(spapr),
 333                                  &error_abort);
 334         sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
 335
 336         spapr->xive = SPAPR_XIVE(dev);
 337
 338         /* Enable the CPU IPIs */
 339         for (i = 0; i < nr_servers; ++i) {
 340             SpaprInterruptControllerClass *sicc
 341                 = SPAPR_INTC_GET_CLASS(spapr->xive);
 342
 343             if (sicc->claim_irq(SPAPR_INTC(spapr->xive), SPAPR_IRQ_IPI + i,
 344                                 false, errp) < 0) {
 345                 return;
 346             }
 347         }
 348
 349         spapr_xive_hcall_init(spapr);
 350     }
 351
 352     spapr->qirqs = qemu_allocate_irqs(spapr_set_irq, spapr,
 353                                       smc->nr_xirqs + SPAPR_XIRQ_BASE);
 354
 355     /*
 356      * Mostly we don't actually need this until reset, except that not
 357      * having this set up can cause VFIO devices to issue a
 358      * false-positive warning during realize(), because they don't yet
 359      * have an in-kernel irq chip.
 360      */
 361     spapr_irq_update_active_intc(spapr);
 362 }
 363
 364 int spapr_irq_claim(SpaprMachineState *spapr, int irq, bool lsi, Error **errp)
 365 {
 366     SpaprInterruptController *intcs[] = ALL_INTCS(spapr);
 367     int i;
 368     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
 369     int rc;
 370
 371     assert(irq >= SPAPR_XIRQ_BASE);
 372     assert(irq < (smc->nr_xirqs + SPAPR_XIRQ_BASE));
 373
 374     for (i = 0; i < ARRAY_SIZE(intcs); i++) {
 375         SpaprInterruptController *intc = intcs[i];
 376         if (intc) {
 377             SpaprInterruptControllerClass *sicc = SPAPR_INTC_GET_CLASS(intc);
 378             rc = sicc->claim_irq(intc, irq, lsi, errp);
 379             if (rc < 0) {
 380                 return rc;
 381             }
 382         }
 383     }
 384
 385     return 0;
 386 }
 387
 388 void spapr_irq_free(SpaprMachineState *spapr, int irq, int num)
 389 {
 390     SpaprInterruptController *intcs[] = ALL_INTCS(spapr);
 391     int i, j;
 392     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
 393
 394     assert(irq >= SPAPR_XIRQ_BASE);
 395     assert((irq + num) <= (smc->nr_xirqs + SPAPR_XIRQ_BASE));
 396
 397     for (i = irq; i < (irq + num); i++) {
 398         for (j = 0; j < ARRAY_SIZE(intcs); j++) {
 399             SpaprInterruptController *intc = intcs[j];
 400
 401             if (intc) {
 402                 SpaprInterruptControllerClass *sicc
 403                     = SPAPR_INTC_GET_CLASS(intc);
 404                 sicc->free_irq(intc, i);
 405             }
 406         }
 407     }
 408 }
 409
 410 qemu_irq spapr_qirq(SpaprMachineState *spapr, int irq)
 411 {
 412     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
 413
 414     /*
 415      * This interface is basically for VIO and PHB devices to find the
 416      * right qemu_irq to manipulate, so we only allow access to the
 417      * external irqs for now.  Currently anything which needs to
 418      * access the IPIs most naturally gets there via the guest side
 419      * interfaces, we can change this if we need to in future.
 420      */
 421     assert(irq >= SPAPR_XIRQ_BASE);
 422     assert(irq < (smc->nr_xirqs + SPAPR_XIRQ_BASE));
 423
 424     if (spapr->ics) {
 425         assert(ics_valid_irq(spapr->ics, irq));
 426     }
 427     if (spapr->xive) {
 428         assert(irq < spapr->xive->nr_irqs);
 429         assert(xive_eas_is_valid(&spapr->xive->eat[irq]));
 430     }
 431
 432     return spapr->qirqs[irq];
 433 }
 434
 435 int spapr_irq_post_load(SpaprMachineState *spapr, int version_id)
 436 {
 437     SpaprInterruptControllerClass *sicc;
 438
 439     spapr_irq_update_active_intc(spapr);
 440     sicc = SPAPR_INTC_GET_CLASS(spapr->active_intc);
 441     return sicc->post_load(spapr->active_intc, version_id);
 442 }
 443
 444 void spapr_irq_reset(SpaprMachineState *spapr, Error **errp)
 445 {
 446     assert(!spapr->irq_map || bitmap_empty(spapr->irq_map, spapr->irq_map_nr));
 447
 448     spapr_irq_update_active_intc(spapr);
 449 }
 450
 451 int spapr_irq_get_phandle(SpaprMachineState *spapr, void *fdt, Error **errp)
 452 {
 453     const char *nodename = "interrupt-controller";
 454     int offset, phandle;
 455
 456     offset = fdt_subnode_offset(fdt, 0, nodename);
 457     if (offset < 0) {
 458         error_setg(errp, "Can't find node \"%s\": %s",
 459                    nodename, fdt_strerror(offset));
 460         return -1;
 461     }
 462
 463     phandle = fdt_get_phandle(fdt, offset);
 464     if (!phandle) {
 465         error_setg(errp, "Can't get phandle of node \"%s\"", nodename);
 466         return -1;
 467     }
 468
 469     return phandle;
 470 }
 471
 472 static void set_active_intc(SpaprMachineState *spapr,
 473                             SpaprInterruptController *new_intc)
 474 {
 475     SpaprInterruptControllerClass *sicc;
 476     uint32_t nr_servers = spapr_max_server_number(spapr);
 477
 478     assert(new_intc);
 479
 480     if (new_intc == spapr->active_intc) {
 481         /* Nothing to do */
 482         return;
 483     }
 484
 485     if (spapr->active_intc) {
 486         sicc = SPAPR_INTC_GET_CLASS(spapr->active_intc);
 487         if (sicc->deactivate) {
 488             sicc->deactivate(spapr->active_intc);
 489         }
 490     }
 491
 492     sicc = SPAPR_INTC_GET_CLASS(new_intc);
 493     if (sicc->activate) {
 494         sicc->activate(new_intc, nr_servers, &error_fatal);
 495     }
 496
 497     spapr->active_intc = new_intc;
 498
 499     /*
 500      * We've changed the kernel irqchip, let VFIO devices know they
 501      * need to readjust.
 502      */
 503     kvm_irqchip_change_notify();
 504 }
 505
 506 void spapr_irq_update_active_intc(SpaprMachineState *spapr)
 507 {
 508     SpaprInterruptController *new_intc;
 509
 510     if (!spapr->ics) {
 511         /*
 512          * XXX before we run CAS, ov5_cas is initialized empty, which
 513          * indicates XICS, even if we have ic-mode=xive.  TODO: clean
 514          * up the CAS path so that we have a clearer way of handling
 515          * this.
 516          */
 517         new_intc = SPAPR_INTC(spapr->xive);
 518     } else if (spapr->ov5_cas
 519                && spapr_ovec_test(spapr->ov5_cas, OV5_XIVE_EXPLOIT)) {
 520         new_intc = SPAPR_INTC(spapr->xive);
 521     } else {
 522         new_intc = SPAPR_INTC(spapr->ics);
 523     }
 524
 525     set_active_intc(spapr, new_intc);
 526 }
 527
 528 /*
 529  * XICS legacy routines - to deprecate one day
 530  */
 531
 532 static int ics_find_free_block(ICSState *ics, int num, int alignnum)
 533 {
 534     int first, i;
 535
 536     for (first = 0; first < ics->nr_irqs; first += alignnum) {
 537         if (num > (ics->nr_irqs - first)) {
 538             return -1;
 539         }
 540         for (i = first; i < first + num; ++i) {
 541             if (!ics_irq_free(ics, i)) {
 542                 break;
 543             }
 544         }
 545         if (i == (first + num)) {
 546             return first;
 547         }
 548     }
 549
 550     return -1;
 551 }
 552
 553 int spapr_irq_find(SpaprMachineState *spapr, int num, bool align, Error **errp)
 554 {
 555     ICSState *ics = spapr->ics;
 556     int first = -1;
 557
 558     assert(ics);
 559
 560     /*
 561      * MSIMesage::data is used for storing VIRQ so
 562      * it has to be aligned to num to support multiple
 563      * MSI vectors. MSI-X is not affected by this.
 564      * The hint is used for the first IRQ, the rest should
 565      * be allocated continuously.
 566      */
 567     if (align) {
 568         assert((num == 1) || (num == 2) || (num == 4) ||
 569                (num == 8) || (num == 16) || (num == 32));
 570         first = ics_find_free_block(ics, num, num);
 571     } else {
 572         first = ics_find_free_block(ics, num, 1);
 573     }
 574
 575     if (first < 0) {
 576         error_setg(errp, "can't find a free %d-IRQ block", num);
 577         return -1;
 578     }
 579
 580     return first + ics->offset;
 581 }
 582
 583 SpaprIrq spapr_irq_xics_legacy = {
 584     .xics        = true,
 585     .xive        = false,
 586 };
 587
 588 static void spapr_irq_register_types(void)
 589 {
 590     type_register_static(&spapr_intc_info);
 591 }
 592
 593 type_init(spapr_irq_register_types)