1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2012 Michael Ellerman, IBM Corporation. 4 * Copyright 2012 Benjamin Herrenschmidt, IBM Corporation 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/kvm_host.h> 9 #include <linux/err.h> 10 #include <linux/kernel_stat.h> 11 #include <linux/pgtable.h> 12 13 #include <asm/kvm_book3s.h> 14 #include <asm/kvm_ppc.h> 15 #include <asm/hvcall.h> 16 #include <asm/xics.h> 17 #include <asm/synch.h> 18 #include <asm/cputhreads.h> 19 #include <asm/ppc-opcode.h> 20 #include <asm/pnv-pci.h> 21 #include <asm/opal.h> 22 #include <asm/smp.h> 23 24 #include "book3s_xics.h" 25 26 #define DEBUG_PASSUP 27 28 int h_ipi_redirect = 1; 29 EXPORT_SYMBOL(h_ipi_redirect); 30 int kvm_irq_bypass = 1; 31 EXPORT_SYMBOL(kvm_irq_bypass); 32 33 static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, 34 u32 new_irq, bool check_resend); 35 static int xics_opal_set_server(unsigned int hw_irq, int server_cpu); 36 37 /* -- ICS routines -- */ 38 static void ics_rm_check_resend(struct kvmppc_xics *xics, 39 struct kvmppc_ics *ics, struct kvmppc_icp *icp) 40 { 41 int i; 42 43 for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) { 44 struct ics_irq_state *state = &ics->irq_state[i]; 45 if (state->resend) 46 icp_rm_deliver_irq(xics, icp, state->number, true); 47 } 48 49 } 50 51 /* -- ICP routines -- */ 52 53 #ifdef CONFIG_SMP 54 static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu) 55 { 56 int hcpu; 57 58 hcpu = hcore << threads_shift; 59 kvmppc_host_rm_ops_hv->rm_core[hcore].rm_data = vcpu; 60 smp_muxed_ipi_set_message(hcpu, PPC_MSG_RM_HOST_ACTION); 61 kvmppc_set_host_ipi(hcpu); 62 smp_mb(); 63 kvmhv_rm_send_ipi(hcpu); 64 } 65 #else 66 static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu) { } 67 #endif 68 69 /* 70 * We start the search from our current CPU Id in the core map 71 * and go in a circle until we get back to our ID looking for a 72 * core that is running in host context and that hasn't already 73 * been targeted for another rm_host_ops. 74 * 75 * In the future, could consider using a fairer algorithm (one 76 * that distributes the IPIs better) 77 * 78 * Returns -1, if no CPU could be found in the host 79 * Else, returns a CPU Id which has been reserved for use 80 */ 81 static inline int grab_next_hostcore(int start, 82 struct kvmppc_host_rm_core *rm_core, int max, int action) 83 { 84 bool success; 85 int core; 86 union kvmppc_rm_state old, new; 87 88 for (core = start + 1; core < max; core++) { 89 old = new = READ_ONCE(rm_core[core].rm_state); 90 91 if (!old.in_host || old.rm_action) 92 continue; 93 94 /* Try to grab this host core if not taken already. */ 95 new.rm_action = action; 96 97 success = cmpxchg64(&rm_core[core].rm_state.raw, 98 old.raw, new.raw) == old.raw; 99 if (success) { 100 /* 101 * Make sure that the store to the rm_action is made 102 * visible before we return to caller (and the 103 * subsequent store to rm_data) to synchronize with 104 * the IPI handler. 105 */ 106 smp_wmb(); 107 return core; 108 } 109 } 110 111 return -1; 112 } 113 114 static inline int find_available_hostcore(int action) 115 { 116 int core; 117 int my_core = smp_processor_id() >> threads_shift; 118 struct kvmppc_host_rm_core *rm_core = kvmppc_host_rm_ops_hv->rm_core; 119 120 core = grab_next_hostcore(my_core, rm_core, cpu_nr_cores(), action); 121 if (core == -1) 122 core = grab_next_hostcore(core, rm_core, my_core, action); 123 124 return core; 125 } 126 127 static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu, 128 struct kvm_vcpu *this_vcpu) 129 { 130 struct kvmppc_icp *this_icp = this_vcpu->arch.icp; 131 int cpu; 132 int hcore; 133 134 /* Mark the target VCPU as having an interrupt pending */ 135 vcpu->stat.queue_intr++; 136 set_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions); 137 138 /* Kick self ? Just set MER and return */ 139 if (vcpu == this_vcpu) { 140 mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_MER); 141 return; 142 } 143 144 if (xive_enabled() && kvmhv_on_pseries()) { 145 /* No XICS access or hypercalls available, too hard */ 146 this_icp->rm_action |= XICS_RM_KICK_VCPU; 147 this_icp->rm_kick_target = vcpu; 148 return; 149 } 150 151 /* 152 * Check if the core is loaded, 153 * if not, find an available host core to post to wake the VCPU, 154 * if we can't find one, set up state to eventually return too hard. 155 */ 156 cpu = vcpu->arch.thread_cpu; 157 if (cpu < 0 || cpu >= nr_cpu_ids) { 158 hcore = -1; 159 if (kvmppc_host_rm_ops_hv && h_ipi_redirect) 160 hcore = find_available_hostcore(XICS_RM_KICK_VCPU); 161 if (hcore != -1) { 162 icp_send_hcore_msg(hcore, vcpu); 163 } else { 164 this_icp->rm_action |= XICS_RM_KICK_VCPU; 165 this_icp->rm_kick_target = vcpu; 166 } 167 return; 168 } 169 170 smp_mb(); 171 kvmhv_rm_send_ipi(cpu); 172 } 173 174 static void icp_rm_clr_vcpu_irq(struct kvm_vcpu *vcpu) 175 { 176 /* Note: Only called on self ! */ 177 clear_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions); 178 mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~LPCR_MER); 179 } 180 181 static inline bool icp_rm_try_update(struct kvmppc_icp *icp, 182 union kvmppc_icp_state old, 183 union kvmppc_icp_state new) 184 { 185 struct kvm_vcpu *this_vcpu = local_paca->kvm_hstate.kvm_vcpu; 186 bool success; 187 188 /* Calculate new output value */ 189 new.out_ee = (new.xisr && (new.pending_pri < new.cppr)); 190 191 /* Attempt atomic update */ 192 success = cmpxchg64(&icp->state.raw, old.raw, new.raw) == old.raw; 193 if (!success) 194 goto bail; 195 196 /* 197 * Check for output state update 198 * 199 * Note that this is racy since another processor could be updating 200 * the state already. This is why we never clear the interrupt output 201 * here, we only ever set it. The clear only happens prior to doing 202 * an update and only by the processor itself. Currently we do it 203 * in Accept (H_XIRR) and Up_Cppr (H_XPPR). 204 * 205 * We also do not try to figure out whether the EE state has changed, 206 * we unconditionally set it if the new state calls for it. The reason 207 * for that is that we opportunistically remove the pending interrupt 208 * flag when raising CPPR, so we need to set it back here if an 209 * interrupt is still pending. 210 */ 211 if (new.out_ee) 212 icp_rm_set_vcpu_irq(icp->vcpu, this_vcpu); 213 214 /* Expose the state change for debug purposes */ 215 this_vcpu->arch.icp->rm_dbgstate = new; 216 this_vcpu->arch.icp->rm_dbgtgt = icp->vcpu; 217 218 bail: 219 return success; 220 } 221 222 static inline int check_too_hard(struct kvmppc_xics *xics, 223 struct kvmppc_icp *icp) 224 { 225 return (xics->real_mode_dbg || icp->rm_action) ? H_TOO_HARD : H_SUCCESS; 226 } 227 228 static void icp_rm_check_resend(struct kvmppc_xics *xics, 229 struct kvmppc_icp *icp) 230 { 231 u32 icsid; 232 233 /* Order this load with the test for need_resend in the caller */ 234 smp_rmb(); 235 for_each_set_bit(icsid, icp->resend_map, xics->max_icsid + 1) { 236 struct kvmppc_ics *ics = xics->ics[icsid]; 237 238 if (!test_and_clear_bit(icsid, icp->resend_map)) 239 continue; 240 if (!ics) 241 continue; 242 ics_rm_check_resend(xics, ics, icp); 243 } 244 } 245 246 static bool icp_rm_try_to_deliver(struct kvmppc_icp *icp, u32 irq, u8 priority, 247 u32 *reject) 248 { 249 union kvmppc_icp_state old_state, new_state; 250 bool success; 251 252 do { 253 old_state = new_state = READ_ONCE(icp->state); 254 255 *reject = 0; 256 257 /* See if we can deliver */ 258 success = new_state.cppr > priority && 259 new_state.mfrr > priority && 260 new_state.pending_pri > priority; 261 262 /* 263 * If we can, check for a rejection and perform the 264 * delivery 265 */ 266 if (success) { 267 *reject = new_state.xisr; 268 new_state.xisr = irq; 269 new_state.pending_pri = priority; 270 } else { 271 /* 272 * If we failed to deliver we set need_resend 273 * so a subsequent CPPR state change causes us 274 * to try a new delivery. 275 */ 276 new_state.need_resend = true; 277 } 278 279 } while (!icp_rm_try_update(icp, old_state, new_state)); 280 281 return success; 282 } 283 284 static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp, 285 u32 new_irq, bool check_resend) 286 { 287 struct ics_irq_state *state; 288 struct kvmppc_ics *ics; 289 u32 reject; 290 u16 src; 291 292 /* 293 * This is used both for initial delivery of an interrupt and 294 * for subsequent rejection. 295 * 296 * Rejection can be racy vs. resends. We have evaluated the 297 * rejection in an atomic ICP transaction which is now complete, 298 * so potentially the ICP can already accept the interrupt again. 299 * 300 * So we need to retry the delivery. Essentially the reject path 301 * boils down to a failed delivery. Always. 302 * 303 * Now the interrupt could also have moved to a different target, 304 * thus we may need to re-do the ICP lookup as well 305 */ 306 307 again: 308 /* Get the ICS state and lock it */ 309 ics = kvmppc_xics_find_ics(xics, new_irq, &src); 310 if (!ics) { 311 /* Unsafe increment, but this does not need to be accurate */ 312 xics->err_noics++; 313 return; 314 } 315 state = &ics->irq_state[src]; 316 317 /* Get a lock on the ICS */ 318 arch_spin_lock(&ics->lock); 319 320 /* Get our server */ 321 if (!icp || state->server != icp->server_num) { 322 icp = kvmppc_xics_find_server(xics->kvm, state->server); 323 if (!icp) { 324 /* Unsafe increment again*/ 325 xics->err_noicp++; 326 goto out; 327 } 328 } 329 330 if (check_resend) 331 if (!state->resend) 332 goto out; 333 334 /* Clear the resend bit of that interrupt */ 335 state->resend = 0; 336 337 /* 338 * If masked, bail out 339 * 340 * Note: PAPR doesn't mention anything about masked pending 341 * when doing a resend, only when doing a delivery. 342 * 343 * However that would have the effect of losing a masked 344 * interrupt that was rejected and isn't consistent with 345 * the whole masked_pending business which is about not 346 * losing interrupts that occur while masked. 347 * 348 * I don't differentiate normal deliveries and resends, this 349 * implementation will differ from PAPR and not lose such 350 * interrupts. 351 */ 352 if (state->priority == MASKED) { 353 state->masked_pending = 1; 354 goto out; 355 } 356 357 /* 358 * Try the delivery, this will set the need_resend flag 359 * in the ICP as part of the atomic transaction if the 360 * delivery is not possible. 361 * 362 * Note that if successful, the new delivery might have itself 363 * rejected an interrupt that was "delivered" before we took the 364 * ics spin lock. 365 * 366 * In this case we do the whole sequence all over again for the 367 * new guy. We cannot assume that the rejected interrupt is less 368 * favored than the new one, and thus doesn't need to be delivered, 369 * because by the time we exit icp_rm_try_to_deliver() the target 370 * processor may well have already consumed & completed it, and thus 371 * the rejected interrupt might actually be already acceptable. 372 */ 373 if (icp_rm_try_to_deliver(icp, new_irq, state->priority, &reject)) { 374 /* 375 * Delivery was successful, did we reject somebody else ? 376 */ 377 if (reject && reject != XICS_IPI) { 378 arch_spin_unlock(&ics->lock); 379 icp->n_reject++; 380 new_irq = reject; 381 check_resend = 0; 382 goto again; 383 } 384 } else { 385 /* 386 * We failed to deliver the interrupt we need to set the 387 * resend map bit and mark the ICS state as needing a resend 388 */ 389 state->resend = 1; 390 391 /* 392 * Make sure when checking resend, we don't miss the resend 393 * if resend_map bit is seen and cleared. 394 */ 395 smp_wmb(); 396 set_bit(ics->icsid, icp->resend_map); 397 398 /* 399 * If the need_resend flag got cleared in the ICP some time 400 * between icp_rm_try_to_deliver() atomic update and now, then 401 * we know it might have missed the resend_map bit. So we 402 * retry 403 */ 404 smp_mb(); 405 if (!icp->state.need_resend) { 406 state->resend = 0; 407 arch_spin_unlock(&ics->lock); 408 check_resend = 0; 409 goto again; 410 } 411 } 412 out: 413 arch_spin_unlock(&ics->lock); 414 } 415 416 static void icp_rm_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp, 417 u8 new_cppr) 418 { 419 union kvmppc_icp_state old_state, new_state; 420 bool resend; 421 422 /* 423 * This handles several related states in one operation: 424 * 425 * ICP State: Down_CPPR 426 * 427 * Load CPPR with new value and if the XISR is 0 428 * then check for resends: 429 * 430 * ICP State: Resend 431 * 432 * If MFRR is more favored than CPPR, check for IPIs 433 * and notify ICS of a potential resend. This is done 434 * asynchronously (when used in real mode, we will have 435 * to exit here). 436 * 437 * We do not handle the complete Check_IPI as documented 438 * here. In the PAPR, this state will be used for both 439 * Set_MFRR and Down_CPPR. However, we know that we aren't 440 * changing the MFRR state here so we don't need to handle 441 * the case of an MFRR causing a reject of a pending irq, 442 * this will have been handled when the MFRR was set in the 443 * first place. 444 * 445 * Thus we don't have to handle rejects, only resends. 446 * 447 * When implementing real mode for HV KVM, resend will lead to 448 * a H_TOO_HARD return and the whole transaction will be handled 449 * in virtual mode. 450 */ 451 do { 452 old_state = new_state = READ_ONCE(icp->state); 453 454 /* Down_CPPR */ 455 new_state.cppr = new_cppr; 456 457 /* 458 * Cut down Resend / Check_IPI / IPI 459 * 460 * The logic is that we cannot have a pending interrupt 461 * trumped by an IPI at this point (see above), so we 462 * know that either the pending interrupt is already an 463 * IPI (in which case we don't care to override it) or 464 * it's either more favored than us or non existent 465 */ 466 if (new_state.mfrr < new_cppr && 467 new_state.mfrr <= new_state.pending_pri) { 468 new_state.pending_pri = new_state.mfrr; 469 new_state.xisr = XICS_IPI; 470 } 471 472 /* Latch/clear resend bit */ 473 resend = new_state.need_resend; 474 new_state.need_resend = 0; 475 476 } while (!icp_rm_try_update(icp, old_state, new_state)); 477 478 /* 479 * Now handle resend checks. Those are asynchronous to the ICP 480 * state update in HW (ie bus transactions) so we can handle them 481 * separately here as well. 482 */ 483 if (resend) { 484 icp->n_check_resend++; 485 icp_rm_check_resend(xics, icp); 486 } 487 } 488 489 490 unsigned long xics_rm_h_xirr(struct kvm_vcpu *vcpu) 491 { 492 union kvmppc_icp_state old_state, new_state; 493 struct kvmppc_xics *xics = vcpu->kvm->arch.xics; 494 struct kvmppc_icp *icp = vcpu->arch.icp; 495 u32 xirr; 496 497 if (!xics || !xics->real_mode) 498 return H_TOO_HARD; 499 500 /* First clear the interrupt */ 501 icp_rm_clr_vcpu_irq(icp->vcpu); 502 503 /* 504 * ICP State: Accept_Interrupt 505 * 506 * Return the pending interrupt (if any) along with the 507 * current CPPR, then clear the XISR & set CPPR to the 508 * pending priority 509 */ 510 do { 511 old_state = new_state = READ_ONCE(icp->state); 512 513 xirr = old_state.xisr | (((u32)old_state.cppr) << 24); 514 if (!old_state.xisr) 515 break; 516 new_state.cppr = new_state.pending_pri; 517 new_state.pending_pri = 0xff; 518 new_state.xisr = 0; 519 520 } while (!icp_rm_try_update(icp, old_state, new_state)); 521 522 /* Return the result in GPR4 */ 523 vcpu->arch.regs.gpr[4] = xirr; 524 525 return check_too_hard(xics, icp); 526 } 527 528 int xics_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, 529 unsigned long mfrr) 530 { 531 union kvmppc_icp_state old_state, new_state; 532 struct kvmppc_xics *xics = vcpu->kvm->arch.xics; 533 struct kvmppc_icp *icp, *this_icp = vcpu->arch.icp; 534 u32 reject; 535 bool resend; 536 bool local; 537 538 if (!xics || !xics->real_mode) 539 return H_TOO_HARD; 540 541 local = this_icp->server_num == server; 542 if (local) 543 icp = this_icp; 544 else 545 icp = kvmppc_xics_find_server(vcpu->kvm, server); 546 if (!icp) 547 return H_PARAMETER; 548 549 /* 550 * ICP state: Set_MFRR 551 * 552 * If the CPPR is more favored than the new MFRR, then 553 * nothing needs to be done as there can be no XISR to 554 * reject. 555 * 556 * ICP state: Check_IPI 557 * 558 * If the CPPR is less favored, then we might be replacing 559 * an interrupt, and thus need to possibly reject it. 560 * 561 * ICP State: IPI 562 * 563 * Besides rejecting any pending interrupts, we also 564 * update XISR and pending_pri to mark IPI as pending. 565 * 566 * PAPR does not describe this state, but if the MFRR is being 567 * made less favored than its earlier value, there might be 568 * a previously-rejected interrupt needing to be resent. 569 * Ideally, we would want to resend only if 570 * prio(pending_interrupt) < mfrr && 571 * prio(pending_interrupt) < cppr 572 * where pending interrupt is the one that was rejected. But 573 * we don't have that state, so we simply trigger a resend 574 * whenever the MFRR is made less favored. 575 */ 576 do { 577 old_state = new_state = READ_ONCE(icp->state); 578 579 /* Set_MFRR */ 580 new_state.mfrr = mfrr; 581 582 /* Check_IPI */ 583 reject = 0; 584 resend = false; 585 if (mfrr < new_state.cppr) { 586 /* Reject a pending interrupt if not an IPI */ 587 if (mfrr <= new_state.pending_pri) { 588 reject = new_state.xisr; 589 new_state.pending_pri = mfrr; 590 new_state.xisr = XICS_IPI; 591 } 592 } 593 594 if (mfrr > old_state.mfrr) { 595 resend = new_state.need_resend; 596 new_state.need_resend = 0; 597 } 598 } while (!icp_rm_try_update(icp, old_state, new_state)); 599 600 /* Handle reject in real mode */ 601 if (reject && reject != XICS_IPI) { 602 this_icp->n_reject++; 603 icp_rm_deliver_irq(xics, icp, reject, false); 604 } 605 606 /* Handle resends in real mode */ 607 if (resend) { 608 this_icp->n_check_resend++; 609 icp_rm_check_resend(xics, icp); 610 } 611 612 return check_too_hard(xics, this_icp); 613 } 614 615 int xics_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) 616 { 617 union kvmppc_icp_state old_state, new_state; 618 struct kvmppc_xics *xics = vcpu->kvm->arch.xics; 619 struct kvmppc_icp *icp = vcpu->arch.icp; 620 u32 reject; 621 622 if (!xics || !xics->real_mode) 623 return H_TOO_HARD; 624 625 /* 626 * ICP State: Set_CPPR 627 * 628 * We can safely compare the new value with the current 629 * value outside of the transaction as the CPPR is only 630 * ever changed by the processor on itself 631 */ 632 if (cppr > icp->state.cppr) { 633 icp_rm_down_cppr(xics, icp, cppr); 634 goto bail; 635 } else if (cppr == icp->state.cppr) 636 return H_SUCCESS; 637 638 /* 639 * ICP State: Up_CPPR 640 * 641 * The processor is raising its priority, this can result 642 * in a rejection of a pending interrupt: 643 * 644 * ICP State: Reject_Current 645 * 646 * We can remove EE from the current processor, the update 647 * transaction will set it again if needed 648 */ 649 icp_rm_clr_vcpu_irq(icp->vcpu); 650 651 do { 652 old_state = new_state = READ_ONCE(icp->state); 653 654 reject = 0; 655 new_state.cppr = cppr; 656 657 if (cppr <= new_state.pending_pri) { 658 reject = new_state.xisr; 659 new_state.xisr = 0; 660 new_state.pending_pri = 0xff; 661 } 662 663 } while (!icp_rm_try_update(icp, old_state, new_state)); 664 665 /* 666 * Check for rejects. They are handled by doing a new delivery 667 * attempt (see comments in icp_rm_deliver_irq). 668 */ 669 if (reject && reject != XICS_IPI) { 670 icp->n_reject++; 671 icp_rm_deliver_irq(xics, icp, reject, false); 672 } 673 bail: 674 return check_too_hard(xics, icp); 675 } 676 677 static int ics_rm_eoi(struct kvm_vcpu *vcpu, u32 irq) 678 { 679 struct kvmppc_xics *xics = vcpu->kvm->arch.xics; 680 struct kvmppc_icp *icp = vcpu->arch.icp; 681 struct kvmppc_ics *ics; 682 struct ics_irq_state *state; 683 u16 src; 684 u32 pq_old, pq_new; 685 686 /* 687 * ICS EOI handling: For LSI, if P bit is still set, we need to 688 * resend it. 689 * 690 * For MSI, we move Q bit into P (and clear Q). If it is set, 691 * resend it. 692 */ 693 694 ics = kvmppc_xics_find_ics(xics, irq, &src); 695 if (!ics) 696 goto bail; 697 698 state = &ics->irq_state[src]; 699 700 if (state->lsi) 701 pq_new = state->pq_state; 702 else 703 do { 704 pq_old = state->pq_state; 705 pq_new = pq_old >> 1; 706 } while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old); 707 708 if (pq_new & PQ_PRESENTED) 709 icp_rm_deliver_irq(xics, NULL, irq, false); 710 711 if (!hlist_empty(&vcpu->kvm->irq_ack_notifier_list)) { 712 icp->rm_action |= XICS_RM_NOTIFY_EOI; 713 icp->rm_eoied_irq = irq; 714 } 715 716 if (state->host_irq) { 717 ++vcpu->stat.pthru_all; 718 if (state->intr_cpu != -1) { 719 int pcpu = raw_smp_processor_id(); 720 721 pcpu = cpu_first_thread_sibling(pcpu); 722 ++vcpu->stat.pthru_host; 723 if (state->intr_cpu != pcpu) { 724 ++vcpu->stat.pthru_bad_aff; 725 xics_opal_set_server(state->host_irq, pcpu); 726 } 727 state->intr_cpu = -1; 728 } 729 } 730 731 bail: 732 return check_too_hard(xics, icp); 733 } 734 735 int xics_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) 736 { 737 struct kvmppc_xics *xics = vcpu->kvm->arch.xics; 738 struct kvmppc_icp *icp = vcpu->arch.icp; 739 u32 irq = xirr & 0x00ffffff; 740 741 if (!xics || !xics->real_mode) 742 return H_TOO_HARD; 743 744 /* 745 * ICP State: EOI 746 * 747 * Note: If EOI is incorrectly used by SW to lower the CPPR 748 * value (ie more favored), we do not check for rejection of 749 * a pending interrupt, this is a SW error and PAPR specifies 750 * that we don't have to deal with it. 751 * 752 * The sending of an EOI to the ICS is handled after the 753 * CPPR update 754 * 755 * ICP State: Down_CPPR which we handle 756 * in a separate function as it's shared with H_CPPR. 757 */ 758 icp_rm_down_cppr(xics, icp, xirr >> 24); 759 760 /* IPIs have no EOI */ 761 if (irq == XICS_IPI) 762 return check_too_hard(xics, icp); 763 764 return ics_rm_eoi(vcpu, irq); 765 } 766 767 static unsigned long eoi_rc; 768 769 static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again) 770 { 771 void __iomem *xics_phys; 772 int64_t rc; 773 774 if (kvmhv_on_pseries()) { 775 unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; 776 777 iosync(); 778 plpar_hcall_raw(H_EOI, retbuf, hwirq); 779 return; 780 } 781 782 rc = pnv_opal_pci_msi_eoi(c, hwirq); 783 784 if (rc) 785 eoi_rc = rc; 786 787 iosync(); 788 789 /* EOI it */ 790 xics_phys = local_paca->kvm_hstate.xics_phys; 791 if (xics_phys) { 792 __raw_rm_writel(xirr, xics_phys + XICS_XIRR); 793 } else { 794 rc = opal_int_eoi(be32_to_cpu(xirr)); 795 *again = rc > 0; 796 } 797 } 798 799 static int xics_opal_set_server(unsigned int hw_irq, int server_cpu) 800 { 801 unsigned int mangle_cpu = get_hard_smp_processor_id(server_cpu) << 2; 802 803 return opal_set_xive(hw_irq, mangle_cpu, DEFAULT_PRIORITY); 804 } 805 806 /* 807 * Increment a per-CPU 32-bit unsigned integer variable. 808 * Safe to call in real-mode. Handles vmalloc'ed addresses 809 * 810 * ToDo: Make this work for any integral type 811 */ 812 813 static inline void this_cpu_inc_rm(unsigned int __percpu *addr) 814 { 815 unsigned long l; 816 unsigned int *raddr; 817 int cpu = smp_processor_id(); 818 819 raddr = per_cpu_ptr(addr, cpu); 820 l = (unsigned long)raddr; 821 822 if (get_region_id(l) == VMALLOC_REGION_ID) { 823 l = vmalloc_to_phys(raddr); 824 raddr = (unsigned int *)l; 825 } 826 ++*raddr; 827 } 828 829 /* 830 * We don't try to update the flags in the irq_desc 'istate' field in 831 * here as would happen in the normal IRQ handling path for several reasons: 832 * - state flags represent internal IRQ state and are not expected to be 833 * updated outside the IRQ subsystem 834 * - more importantly, these are useful for edge triggered interrupts, 835 * IRQ probing, etc., but we are only handling MSI/MSIx interrupts here 836 * and these states shouldn't apply to us. 837 * 838 * However, we do update irq_stats - we somewhat duplicate the code in 839 * kstat_incr_irqs_this_cpu() for this since this function is defined 840 * in irq/internal.h which we don't want to include here. 841 * The only difference is that desc->kstat_irqs is an allocated per CPU 842 * variable and could have been vmalloc'ed, so we can't directly 843 * call __this_cpu_inc() on it. The kstat structure is a static 844 * per CPU variable and it should be accessible by real-mode KVM. 845 * 846 */ 847 static void kvmppc_rm_handle_irq_desc(struct irq_desc *desc) 848 { 849 this_cpu_inc_rm(desc->kstat_irqs); 850 __this_cpu_inc(kstat.irqs_sum); 851 } 852 853 long kvmppc_deliver_irq_passthru(struct kvm_vcpu *vcpu, 854 __be32 xirr, 855 struct kvmppc_irq_map *irq_map, 856 struct kvmppc_passthru_irqmap *pimap, 857 bool *again) 858 { 859 struct kvmppc_xics *xics; 860 struct kvmppc_icp *icp; 861 struct kvmppc_ics *ics; 862 struct ics_irq_state *state; 863 u32 irq; 864 u16 src; 865 u32 pq_old, pq_new; 866 867 irq = irq_map->v_hwirq; 868 xics = vcpu->kvm->arch.xics; 869 icp = vcpu->arch.icp; 870 871 kvmppc_rm_handle_irq_desc(irq_map->desc); 872 873 ics = kvmppc_xics_find_ics(xics, irq, &src); 874 if (!ics) 875 return 2; 876 877 state = &ics->irq_state[src]; 878 879 /* only MSIs register bypass producers, so it must be MSI here */ 880 do { 881 pq_old = state->pq_state; 882 pq_new = ((pq_old << 1) & 3) | PQ_PRESENTED; 883 } while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old); 884 885 /* Test P=1, Q=0, this is the only case where we present */ 886 if (pq_new == PQ_PRESENTED) 887 icp_rm_deliver_irq(xics, icp, irq, false); 888 889 /* EOI the interrupt */ 890 icp_eoi(irq_desc_get_chip(irq_map->desc), irq_map->r_hwirq, xirr, 891 again); 892 893 if (check_too_hard(xics, icp) == H_TOO_HARD) 894 return 2; 895 else 896 return -2; 897 } 898 899 /* --- Non-real mode XICS-related built-in routines --- */ 900 901 /** 902 * Host Operations poked by RM KVM 903 */ 904 static void rm_host_ipi_action(int action, void *data) 905 { 906 switch (action) { 907 case XICS_RM_KICK_VCPU: 908 kvmppc_host_rm_ops_hv->vcpu_kick(data); 909 break; 910 default: 911 WARN(1, "Unexpected rm_action=%d data=%p\n", action, data); 912 break; 913 } 914 915 } 916 917 void kvmppc_xics_ipi_action(void) 918 { 919 int core; 920 unsigned int cpu = smp_processor_id(); 921 struct kvmppc_host_rm_core *rm_corep; 922 923 core = cpu >> threads_shift; 924 rm_corep = &kvmppc_host_rm_ops_hv->rm_core[core]; 925 926 if (rm_corep->rm_data) { 927 rm_host_ipi_action(rm_corep->rm_state.rm_action, 928 rm_corep->rm_data); 929 /* Order these stores against the real mode KVM */ 930 rm_corep->rm_data = NULL; 931 smp_wmb(); 932 rm_corep->rm_state.rm_action = 0; 933 } 934 } 935