hw/xics.c

   1 /*
   2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
   3  *
   4  * PAPR Virtualized Interrupt System, aka ICS/ICP aka xics
   5  *
   6  * Copyright (c) 2010,2011 David Gibson, IBM Corporation.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24  * THE SOFTWARE.
  25  *
  26  */
  27
  28 #include "hw.h"
  29 #include "trace.h"
  30 #include "hw/spapr.h"
  31 #include "hw/xics.h"
  32
  33 /*
  34  * ICP: Presentation layer
  35  */
  36
  37 struct icp_server_state {
  38     uint32_t xirr;
  39     uint8_t pending_priority;
  40     uint8_t mfrr;
  41     qemu_irq output;
  42 };
  43
  44 #define XISR_MASK  0x00ffffff
  45 #define CPPR_MASK  0xff000000
  46
  47 #define XISR(ss)   (((ss)->xirr) & XISR_MASK)
  48 #define CPPR(ss)   (((ss)->xirr) >> 24)
  49
  50 struct ics_state;
  51
  52 struct icp_state {
  53     long nr_servers;
  54     struct icp_server_state *ss;
  55     struct ics_state *ics;
  56 };
  57
  58 static void ics_reject(struct ics_state *ics, int nr);
  59 static void ics_resend(struct ics_state *ics);
  60 static void ics_eoi(struct ics_state *ics, int nr);
  61
  62 static void icp_check_ipi(struct icp_state *icp, int server)
  63 {
  64     struct icp_server_state *ss = icp->ss + server;
  65
  66     if (XISR(ss) && (ss->pending_priority <= ss->mfrr)) {
  67         return;
  68     }
  69
  70     trace_xics_icp_check_ipi(server, ss->mfrr);
  71
  72     if (XISR(ss)) {
  73         ics_reject(icp->ics, XISR(ss));
  74     }
  75
  76     ss->xirr = (ss->xirr & ~XISR_MASK) | XICS_IPI;
  77     ss->pending_priority = ss->mfrr;
  78     qemu_irq_raise(ss->output);
  79 }
  80
  81 static void icp_resend(struct icp_state *icp, int server)
  82 {
  83     struct icp_server_state *ss = icp->ss + server;
  84
  85     if (ss->mfrr < CPPR(ss)) {
  86         icp_check_ipi(icp, server);
  87     }
  88     ics_resend(icp->ics);
  89 }
  90
  91 static void icp_set_cppr(struct icp_state *icp, int server, uint8_t cppr)
  92 {
  93     struct icp_server_state *ss = icp->ss + server;
  94     uint8_t old_cppr;
  95     uint32_t old_xisr;
  96
  97     old_cppr = CPPR(ss);
  98     ss->xirr = (ss->xirr & ~CPPR_MASK) | (cppr << 24);
  99
 100     if (cppr < old_cppr) {
 101         if (XISR(ss) && (cppr <= ss->pending_priority)) {
 102             old_xisr = XISR(ss);
 103             ss->xirr &= ~XISR_MASK; /* Clear XISR */
 104             qemu_irq_lower(ss->output);
 105             ics_reject(icp->ics, old_xisr);
 106         }
 107     } else {
 108         if (!XISR(ss)) {
 109             icp_resend(icp, server);
 110         }
 111     }
 112 }
 113
 114 static void icp_set_mfrr(struct icp_state *icp, int server, uint8_t mfrr)
 115 {
 116     struct icp_server_state *ss = icp->ss + server;
 117
 118     ss->mfrr = mfrr;
 119     if (mfrr < CPPR(ss)) {
 120         icp_check_ipi(icp, server);
 121     }
 122 }
 123
 124 static uint32_t icp_accept(struct icp_server_state *ss)
 125 {
 126     uint32_t xirr = ss->xirr;
 127
 128     qemu_irq_lower(ss->output);
 129     ss->xirr = ss->pending_priority << 24;
 130
 131     trace_xics_icp_accept(xirr, ss->xirr);
 132
 133     return xirr;
 134 }
 135
 136 static void icp_eoi(struct icp_state *icp, int server, uint32_t xirr)
 137 {
 138     struct icp_server_state *ss = icp->ss + server;
 139
 140     /* Send EOI -> ICS */
 141     ss->xirr = (ss->xirr & ~CPPR_MASK) | (xirr & CPPR_MASK);
 142     trace_xics_icp_eoi(server, xirr, ss->xirr);
 143     ics_eoi(icp->ics, xirr & XISR_MASK);
 144     if (!XISR(ss)) {
 145         icp_resend(icp, server);
 146     }
 147 }
 148
 149 static void icp_irq(struct icp_state *icp, int server, int nr, uint8_t priority)
 150 {
 151     struct icp_server_state *ss = icp->ss + server;
 152
 153     trace_xics_icp_irq(server, nr, priority);
 154
 155     if ((priority >= CPPR(ss))
 156         || (XISR(ss) && (ss->pending_priority <= priority))) {
 157         ics_reject(icp->ics, nr);
 158     } else {
 159         if (XISR(ss)) {
 160             ics_reject(icp->ics, XISR(ss));
 161         }
 162         ss->xirr = (ss->xirr & ~XISR_MASK) | (nr & XISR_MASK);
 163         ss->pending_priority = priority;
 164         trace_xics_icp_raise(ss->xirr, ss->pending_priority);
 165         qemu_irq_raise(ss->output);
 166     }
 167 }
 168
 169 /*
 170  * ICS: Source layer
 171  */
 172
 173 struct ics_irq_state {
 174     int server;
 175     uint8_t priority;
 176     uint8_t saved_priority;
 177 #define XICS_STATUS_ASSERTED           0x1
 178 #define XICS_STATUS_SENT               0x2
 179 #define XICS_STATUS_REJECTED           0x4
 180 #define XICS_STATUS_MASKED_PENDING     0x8
 181     uint8_t status;
 182 };
 183
 184 struct ics_state {
 185     int nr_irqs;
 186     int offset;
 187     qemu_irq *qirqs;
 188     bool *islsi;
 189     struct ics_irq_state *irqs;
 190     struct icp_state *icp;
 191 };
 192
 193 static int ics_valid_irq(struct ics_state *ics, uint32_t nr)
 194 {
 195     return (nr >= ics->offset)
 196         && (nr < (ics->offset + ics->nr_irqs));
 197 }
 198
 199 static void resend_msi(struct ics_state *ics, int srcno)
 200 {
 201     struct ics_irq_state *irq = ics->irqs + srcno;
 202
 203     /* FIXME: filter by server#? */
 204     if (irq->status & XICS_STATUS_REJECTED) {
 205         irq->status &= ~XICS_STATUS_REJECTED;
 206         if (irq->priority != 0xff) {
 207             icp_irq(ics->icp, irq->server, srcno + ics->offset,
 208                     irq->priority);
 209         }
 210     }
 211 }
 212
 213 static void resend_lsi(struct ics_state *ics, int srcno)
 214 {
 215     struct ics_irq_state *irq = ics->irqs + srcno;
 216
 217     if ((irq->priority != 0xff)
 218         && (irq->status & XICS_STATUS_ASSERTED)
 219         && !(irq->status & XICS_STATUS_SENT)) {
 220         irq->status |= XICS_STATUS_SENT;
 221         icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
 222     }
 223 }
 224
 225 static void set_irq_msi(struct ics_state *ics, int srcno, int val)
 226 {
 227     struct ics_irq_state *irq = ics->irqs + srcno;
 228
 229     trace_xics_set_irq_msi(srcno, srcno + ics->offset);
 230
 231     if (val) {
 232         if (irq->priority == 0xff) {
 233             irq->status |= XICS_STATUS_MASKED_PENDING;
 234             trace_xics_masked_pending();
 235         } else  {
 236             icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
 237         }
 238     }
 239 }
 240
 241 static void set_irq_lsi(struct ics_state *ics, int srcno, int val)
 242 {
 243     struct ics_irq_state *irq = ics->irqs + srcno;
 244
 245     trace_xics_set_irq_lsi(srcno, srcno + ics->offset);
 246     if (val) {
 247         irq->status |= XICS_STATUS_ASSERTED;
 248     } else {
 249         irq->status &= ~XICS_STATUS_ASSERTED;
 250     }
 251     resend_lsi(ics, srcno);
 252 }
 253
 254 static void ics_set_irq(void *opaque, int srcno, int val)
 255 {
 256     struct ics_state *ics = (struct ics_state *)opaque;
 257
 258     if (ics->islsi[srcno]) {
 259         set_irq_lsi(ics, srcno, val);
 260     } else {
 261         set_irq_msi(ics, srcno, val);
 262     }
 263 }
 264
 265 static void write_xive_msi(struct ics_state *ics, int srcno)
 266 {
 267     struct ics_irq_state *irq = ics->irqs + srcno;
 268
 269     if (!(irq->status & XICS_STATUS_MASKED_PENDING)
 270         || (irq->priority == 0xff)) {
 271         return;
 272     }
 273
 274     irq->status &= ~XICS_STATUS_MASKED_PENDING;
 275     icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
 276 }
 277
 278 static void write_xive_lsi(struct ics_state *ics, int srcno)
 279 {
 280     resend_lsi(ics, srcno);
 281 }
 282
 283 static void ics_write_xive(struct ics_state *ics, int nr, int server,
 284                            uint8_t priority, uint8_t saved_priority)
 285 {
 286     int srcno = nr - ics->offset;
 287     struct ics_irq_state *irq = ics->irqs + srcno;
 288
 289     irq->server = server;
 290     irq->priority = priority;
 291     irq->saved_priority = saved_priority;
 292
 293     trace_xics_ics_write_xive(nr, srcno, server, priority);
 294
 295     if (ics->islsi[srcno]) {
 296         write_xive_lsi(ics, srcno);
 297     } else {
 298         write_xive_msi(ics, srcno);
 299     }
 300 }
 301
 302 static void ics_reject(struct ics_state *ics, int nr)
 303 {
 304     struct ics_irq_state *irq = ics->irqs + nr - ics->offset;
 305
 306     trace_xics_ics_reject(nr, nr - ics->offset);
 307     irq->status |= XICS_STATUS_REJECTED; /* Irrelevant but harmless for LSI */
 308     irq->status &= ~XICS_STATUS_SENT; /* Irrelevant but harmless for MSI */
 309 }
 310
 311 static void ics_resend(struct ics_state *ics)
 312 {
 313     int i;
 314
 315     for (i = 0; i < ics->nr_irqs; i++) {
 316         /* FIXME: filter by server#? */
 317         if (ics->islsi[i]) {
 318             resend_lsi(ics, i);
 319         } else {
 320             resend_msi(ics, i);
 321         }
 322     }
 323 }
 324
 325 static void ics_eoi(struct ics_state *ics, int nr)
 326 {
 327     int srcno = nr - ics->offset;
 328     struct ics_irq_state *irq = ics->irqs + srcno;
 329
 330     trace_xics_ics_eoi(nr);
 331
 332     if (ics->islsi[srcno]) {
 333         irq->status &= ~XICS_STATUS_SENT;
 334     }
 335 }
 336
 337 /*
 338  * Exported functions
 339  */
 340
 341 qemu_irq xics_get_qirq(struct icp_state *icp, int irq)
 342 {
 343     if (!ics_valid_irq(icp->ics, irq)) {
 344         return NULL;
 345     }
 346
 347     return icp->ics->qirqs[irq - icp->ics->offset];
 348 }
 349
 350 void xics_set_irq_type(struct icp_state *icp, int irq, bool lsi)
 351 {
 352     assert(ics_valid_irq(icp->ics, irq));
 353
 354     icp->ics->islsi[irq - icp->ics->offset] = lsi;
 355 }
 356
 357 static target_ulong h_cppr(PowerPCCPU *cpu, sPAPREnvironment *spapr,
 358                            target_ulong opcode, target_ulong *args)
 359 {
 360     CPUState *cs = CPU(cpu);
 361     target_ulong cppr = args[0];
 362
 363     icp_set_cppr(spapr->icp, cs->cpu_index, cppr);
 364     return H_SUCCESS;
 365 }
 366
 367 static target_ulong h_ipi(PowerPCCPU *cpu, sPAPREnvironment *spapr,
 368                           target_ulong opcode, target_ulong *args)
 369 {
 370     target_ulong server = args[0];
 371     target_ulong mfrr = args[1];
 372
 373     if (server >= spapr->icp->nr_servers) {
 374         return H_PARAMETER;
 375     }
 376
 377     icp_set_mfrr(spapr->icp, server, mfrr);
 378     return H_SUCCESS;
 379 }
 380
 381 static target_ulong h_xirr(PowerPCCPU *cpu, sPAPREnvironment *spapr,
 382                            target_ulong opcode, target_ulong *args)
 383 {
 384     CPUState *cs = CPU(cpu);
 385     uint32_t xirr = icp_accept(spapr->icp->ss + cs->cpu_index);
 386
 387     args[0] = xirr;
 388     return H_SUCCESS;
 389 }
 390
 391 static target_ulong h_eoi(PowerPCCPU *cpu, sPAPREnvironment *spapr,
 392                           target_ulong opcode, target_ulong *args)
 393 {
 394     CPUState *cs = CPU(cpu);
 395     target_ulong xirr = args[0];
 396
 397     icp_eoi(spapr->icp, cs->cpu_index, xirr);
 398     return H_SUCCESS;
 399 }
 400
 401 static void rtas_set_xive(sPAPREnvironment *spapr, uint32_t token,
 402                           uint32_t nargs, target_ulong args,
 403                           uint32_t nret, target_ulong rets)
 404 {
 405     struct ics_state *ics = spapr->icp->ics;
 406     uint32_t nr, server, priority;
 407
 408     if ((nargs != 3) || (nret != 1)) {
 409         rtas_st(rets, 0, -3);
 410         return;
 411     }
 412
 413     nr = rtas_ld(args, 0);
 414     server = rtas_ld(args, 1);
 415     priority = rtas_ld(args, 2);
 416
 417     if (!ics_valid_irq(ics, nr) || (server >= ics->icp->nr_servers)
 418         || (priority > 0xff)) {
 419         rtas_st(rets, 0, -3);
 420         return;
 421     }
 422
 423     ics_write_xive(ics, nr, server, priority, priority);
 424
 425     rtas_st(rets, 0, 0); /* Success */
 426 }
 427
 428 static void rtas_get_xive(sPAPREnvironment *spapr, uint32_t token,
 429                           uint32_t nargs, target_ulong args,
 430                           uint32_t nret, target_ulong rets)
 431 {
 432     struct ics_state *ics = spapr->icp->ics;
 433     uint32_t nr;
 434
 435     if ((nargs != 1) || (nret != 3)) {
 436         rtas_st(rets, 0, -3);
 437         return;
 438     }
 439
 440     nr = rtas_ld(args, 0);
 441
 442     if (!ics_valid_irq(ics, nr)) {
 443         rtas_st(rets, 0, -3);
 444         return;
 445     }
 446
 447     rtas_st(rets, 0, 0); /* Success */
 448     rtas_st(rets, 1, ics->irqs[nr - ics->offset].server);
 449     rtas_st(rets, 2, ics->irqs[nr - ics->offset].priority);
 450 }
 451
 452 static void rtas_int_off(sPAPREnvironment *spapr, uint32_t token,
 453                          uint32_t nargs, target_ulong args,
 454                          uint32_t nret, target_ulong rets)
 455 {
 456     struct ics_state *ics = spapr->icp->ics;
 457     uint32_t nr;
 458
 459     if ((nargs != 1) || (nret != 1)) {
 460         rtas_st(rets, 0, -3);
 461         return;
 462     }
 463
 464     nr = rtas_ld(args, 0);
 465
 466     if (!ics_valid_irq(ics, nr)) {
 467         rtas_st(rets, 0, -3);
 468         return;
 469     }
 470
 471     ics_write_xive(ics, nr, ics->irqs[nr - ics->offset].server, 0xff,
 472                    ics->irqs[nr - ics->offset].priority);
 473
 474     rtas_st(rets, 0, 0); /* Success */
 475 }
 476
 477 static void rtas_int_on(sPAPREnvironment *spapr, uint32_t token,
 478                         uint32_t nargs, target_ulong args,
 479                         uint32_t nret, target_ulong rets)
 480 {
 481     struct ics_state *ics = spapr->icp->ics;
 482     uint32_t nr;
 483
 484     if ((nargs != 1) || (nret != 1)) {
 485         rtas_st(rets, 0, -3);
 486         return;
 487     }
 488
 489     nr = rtas_ld(args, 0);
 490
 491     if (!ics_valid_irq(ics, nr)) {
 492         rtas_st(rets, 0, -3);
 493         return;
 494     }
 495
 496     ics_write_xive(ics, nr, ics->irqs[nr - ics->offset].server,
 497                    ics->irqs[nr - ics->offset].saved_priority,
 498                    ics->irqs[nr - ics->offset].saved_priority);
 499
 500     rtas_st(rets, 0, 0); /* Success */
 501 }
 502
 503 static void xics_reset(void *opaque)
 504 {
 505     struct icp_state *icp = (struct icp_state *)opaque;
 506     struct ics_state *ics = icp->ics;
 507     int i;
 508
 509     for (i = 0; i < icp->nr_servers; i++) {
 510         icp->ss[i].xirr = 0;
 511         icp->ss[i].pending_priority = 0xff;
 512         icp->ss[i].mfrr = 0xff;
 513         /* Make all outputs are deasserted */
 514         qemu_set_irq(icp->ss[i].output, 0);
 515     }
 516
 517     memset(ics->irqs, 0, sizeof(struct ics_irq_state) * ics->nr_irqs);
 518     for (i = 0; i < ics->nr_irqs; i++) {
 519         ics->irqs[i].priority = 0xff;
 520         ics->irqs[i].saved_priority = 0xff;
 521     }
 522 }
 523
 524 struct icp_state *xics_system_init(int nr_irqs)
 525 {
 526     CPUPPCState *env;
 527     CPUState *cpu;
 528     int max_server_num;
 529     struct icp_state *icp;
 530     struct ics_state *ics;
 531
 532     max_server_num = -1;
 533     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 534         cpu = CPU(ppc_env_get_cpu(env));
 535         if (cpu->cpu_index > max_server_num) {
 536             max_server_num = cpu->cpu_index;
 537         }
 538     }
 539
 540     icp = g_malloc0(sizeof(*icp));
 541     icp->nr_servers = max_server_num + 1;
 542     icp->ss = g_malloc0(icp->nr_servers*sizeof(struct icp_server_state));
 543
 544     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 545         cpu = CPU(ppc_env_get_cpu(env));
 546         struct icp_server_state *ss = &icp->ss[cpu->cpu_index];
 547
 548         switch (PPC_INPUT(env)) {
 549         case PPC_FLAGS_INPUT_POWER7:
 550             ss->output = env->irq_inputs[POWER7_INPUT_INT];
 551             break;
 552
 553         case PPC_FLAGS_INPUT_970:
 554             ss->output = env->irq_inputs[PPC970_INPUT_INT];
 555             break;
 556
 557         default:
 558             hw_error("XICS interrupt model does not support this CPU bus "
 559                      "model\n");
 560             exit(1);
 561         }
 562     }
 563
 564     ics = g_malloc0(sizeof(*ics));
 565     ics->nr_irqs = nr_irqs;
 566     ics->offset = XICS_IRQ_BASE;
 567     ics->irqs = g_malloc0(nr_irqs * sizeof(struct ics_irq_state));
 568     ics->islsi = g_malloc0(nr_irqs * sizeof(bool));
 569
 570     icp->ics = ics;
 571     ics->icp = icp;
 572
 573     ics->qirqs = qemu_allocate_irqs(ics_set_irq, ics, nr_irqs);
 574
 575     spapr_register_hypercall(H_CPPR, h_cppr);
 576     spapr_register_hypercall(H_IPI, h_ipi);
 577     spapr_register_hypercall(H_XIRR, h_xirr);
 578     spapr_register_hypercall(H_EOI, h_eoi);
 579
 580     spapr_rtas_register("ibm,set-xive", rtas_set_xive);
 581     spapr_rtas_register("ibm,get-xive", rtas_get_xive);
 582     spapr_rtas_register("ibm,int-off", rtas_int_off);
 583     spapr_rtas_register("ibm,int-on", rtas_int_on);
 584
 585     qemu_register_reset(xics_reset, icp);
 586
 587     return icp;
 588 }