1 /* 2 * RISC-V CPU helpers for qemu. 3 * 4 * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu 5 * Copyright (c) 2017-2018 SiFive, Inc. 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms and conditions of the GNU General Public License, 9 * version 2 or later, as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "qemu/log.h" 22 #include "qemu/main-loop.h" 23 #include "cpu.h" 24 #include "exec/exec-all.h" 25 #include "tcg/tcg-op.h" 26 #include "trace.h" 27 #include "semihosting/common-semi.h" 28 29 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch) 30 { 31 #ifdef CONFIG_USER_ONLY 32 return 0; 33 #else 34 return env->priv; 35 #endif 36 } 37 38 static RISCVMXL cpu_get_xl(CPURISCVState *env) 39 { 40 #if defined(TARGET_RISCV32) 41 return MXL_RV32; 42 #elif defined(CONFIG_USER_ONLY) 43 return MXL_RV64; 44 #else 45 RISCVMXL xl = riscv_cpu_mxl(env); 46 47 /* 48 * When emulating a 32-bit-only cpu, use RV32. 49 * When emulating a 64-bit cpu, and MXL has been reduced to RV32, 50 * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened 51 * back to RV64 for lower privs. 52 */ 53 if (xl != MXL_RV32) { 54 switch (env->priv) { 55 case PRV_M: 56 break; 57 case PRV_U: 58 xl = get_field(env->mstatus, MSTATUS64_UXL); 59 break; 60 default: /* PRV_S | PRV_H */ 61 xl = get_field(env->mstatus, MSTATUS64_SXL); 62 break; 63 } 64 } 65 return xl; 66 #endif 67 } 68 69 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc, 70 target_ulong *cs_base, uint32_t *pflags) 71 { 72 CPUState *cs = env_cpu(env); 73 RISCVCPU *cpu = RISCV_CPU(cs); 74 75 uint32_t flags = 0; 76 77 *pc = env->pc; 78 *cs_base = 0; 79 80 if (riscv_has_ext(env, RVV) || cpu->cfg.ext_zve64f) { 81 /* 82 * If env->vl equals to VLMAX, we can use generic vector operation 83 * expanders (GVEC) to accerlate the vector operations. 84 * However, as LMUL could be a fractional number. The maximum 85 * vector size can be operated might be less than 8 bytes, 86 * which is not supported by GVEC. So we set vl_eq_vlmax flag to true 87 * only when maxsz >= 8 bytes. 88 */ 89 uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype); 90 uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW); 91 uint32_t maxsz = vlmax << sew; 92 bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) && 93 (maxsz >= 8); 94 flags = FIELD_DP32(flags, TB_FLAGS, VILL, 95 FIELD_EX64(env->vtype, VTYPE, VILL)); 96 flags = FIELD_DP32(flags, TB_FLAGS, SEW, sew); 97 flags = FIELD_DP32(flags, TB_FLAGS, LMUL, 98 FIELD_EX64(env->vtype, VTYPE, VLMUL)); 99 flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax); 100 } else { 101 flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1); 102 } 103 104 #ifdef CONFIG_USER_ONLY 105 flags |= TB_FLAGS_MSTATUS_FS; 106 flags |= TB_FLAGS_MSTATUS_VS; 107 #else 108 flags |= cpu_mmu_index(env, 0); 109 if (riscv_cpu_fp_enabled(env)) { 110 flags |= env->mstatus & MSTATUS_FS; 111 } 112 113 if (riscv_cpu_vector_enabled(env)) { 114 flags |= env->mstatus & MSTATUS_VS; 115 } 116 117 if (riscv_has_ext(env, RVH)) { 118 if (env->priv == PRV_M || 119 (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) || 120 (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) && 121 get_field(env->hstatus, HSTATUS_HU))) { 122 flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1); 123 } 124 125 flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS, 126 get_field(env->mstatus_hs, MSTATUS_FS)); 127 128 flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS, 129 get_field(env->mstatus_hs, MSTATUS_VS)); 130 } 131 if (riscv_has_ext(env, RVJ)) { 132 int priv = flags & TB_FLAGS_PRIV_MMU_MASK; 133 bool pm_enabled = false; 134 switch (priv) { 135 case PRV_U: 136 pm_enabled = env->mmte & U_PM_ENABLE; 137 break; 138 case PRV_S: 139 pm_enabled = env->mmte & S_PM_ENABLE; 140 break; 141 case PRV_M: 142 pm_enabled = env->mmte & M_PM_ENABLE; 143 break; 144 default: 145 g_assert_not_reached(); 146 } 147 flags = FIELD_DP32(flags, TB_FLAGS, PM_ENABLED, pm_enabled); 148 } 149 #endif 150 151 flags = FIELD_DP32(flags, TB_FLAGS, XL, cpu_get_xl(env)); 152 153 *pflags = flags; 154 } 155 156 #ifndef CONFIG_USER_ONLY 157 static int riscv_cpu_local_irq_pending(CPURISCVState *env) 158 { 159 target_ulong virt_enabled = riscv_cpu_virt_enabled(env); 160 161 target_ulong mstatus_mie = get_field(env->mstatus, MSTATUS_MIE); 162 target_ulong mstatus_sie = get_field(env->mstatus, MSTATUS_SIE); 163 164 target_ulong pending = env->mip & env->mie; 165 166 target_ulong mie = env->priv < PRV_M || 167 (env->priv == PRV_M && mstatus_mie); 168 target_ulong sie = env->priv < PRV_S || 169 (env->priv == PRV_S && mstatus_sie); 170 target_ulong hsie = virt_enabled || sie; 171 target_ulong vsie = virt_enabled && sie; 172 173 target_ulong irqs = 174 (pending & ~env->mideleg & -mie) | 175 (pending & env->mideleg & ~env->hideleg & -hsie) | 176 (pending & env->mideleg & env->hideleg & -vsie); 177 178 if (irqs) { 179 return ctz64(irqs); /* since non-zero */ 180 } else { 181 return RISCV_EXCP_NONE; /* indicates no pending interrupt */ 182 } 183 } 184 185 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request) 186 { 187 if (interrupt_request & CPU_INTERRUPT_HARD) { 188 RISCVCPU *cpu = RISCV_CPU(cs); 189 CPURISCVState *env = &cpu->env; 190 int interruptno = riscv_cpu_local_irq_pending(env); 191 if (interruptno >= 0) { 192 cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno; 193 riscv_cpu_do_interrupt(cs); 194 return true; 195 } 196 } 197 return false; 198 } 199 200 /* Return true is floating point support is currently enabled */ 201 bool riscv_cpu_fp_enabled(CPURISCVState *env) 202 { 203 if (env->mstatus & MSTATUS_FS) { 204 if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) { 205 return false; 206 } 207 return true; 208 } 209 210 return false; 211 } 212 213 /* Return true is vector support is currently enabled */ 214 bool riscv_cpu_vector_enabled(CPURISCVState *env) 215 { 216 if (env->mstatus & MSTATUS_VS) { 217 if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) { 218 return false; 219 } 220 return true; 221 } 222 223 return false; 224 } 225 226 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env) 227 { 228 uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS | 229 MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE | 230 MSTATUS64_UXL | MSTATUS_VS; 231 bool current_virt = riscv_cpu_virt_enabled(env); 232 233 g_assert(riscv_has_ext(env, RVH)); 234 235 if (current_virt) { 236 /* Current V=1 and we are about to change to V=0 */ 237 env->vsstatus = env->mstatus & mstatus_mask; 238 env->mstatus &= ~mstatus_mask; 239 env->mstatus |= env->mstatus_hs; 240 241 env->vstvec = env->stvec; 242 env->stvec = env->stvec_hs; 243 244 env->vsscratch = env->sscratch; 245 env->sscratch = env->sscratch_hs; 246 247 env->vsepc = env->sepc; 248 env->sepc = env->sepc_hs; 249 250 env->vscause = env->scause; 251 env->scause = env->scause_hs; 252 253 env->vstval = env->stval; 254 env->stval = env->stval_hs; 255 256 env->vsatp = env->satp; 257 env->satp = env->satp_hs; 258 } else { 259 /* Current V=0 and we are about to change to V=1 */ 260 env->mstatus_hs = env->mstatus & mstatus_mask; 261 env->mstatus &= ~mstatus_mask; 262 env->mstatus |= env->vsstatus; 263 264 env->stvec_hs = env->stvec; 265 env->stvec = env->vstvec; 266 267 env->sscratch_hs = env->sscratch; 268 env->sscratch = env->vsscratch; 269 270 env->sepc_hs = env->sepc; 271 env->sepc = env->vsepc; 272 273 env->scause_hs = env->scause; 274 env->scause = env->vscause; 275 276 env->stval_hs = env->stval; 277 env->stval = env->vstval; 278 279 env->satp_hs = env->satp; 280 env->satp = env->vsatp; 281 } 282 } 283 284 bool riscv_cpu_virt_enabled(CPURISCVState *env) 285 { 286 if (!riscv_has_ext(env, RVH)) { 287 return false; 288 } 289 290 return get_field(env->virt, VIRT_ONOFF); 291 } 292 293 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable) 294 { 295 if (!riscv_has_ext(env, RVH)) { 296 return; 297 } 298 299 /* Flush the TLB on all virt mode changes. */ 300 if (get_field(env->virt, VIRT_ONOFF) != enable) { 301 tlb_flush(env_cpu(env)); 302 } 303 304 env->virt = set_field(env->virt, VIRT_ONOFF, enable); 305 } 306 307 bool riscv_cpu_two_stage_lookup(int mmu_idx) 308 { 309 return mmu_idx & TB_FLAGS_PRIV_HYP_ACCESS_MASK; 310 } 311 312 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts) 313 { 314 CPURISCVState *env = &cpu->env; 315 if (env->miclaim & interrupts) { 316 return -1; 317 } else { 318 env->miclaim |= interrupts; 319 return 0; 320 } 321 } 322 323 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value) 324 { 325 CPURISCVState *env = &cpu->env; 326 CPUState *cs = CPU(cpu); 327 uint32_t old = env->mip; 328 bool locked = false; 329 330 if (!qemu_mutex_iothread_locked()) { 331 locked = true; 332 qemu_mutex_lock_iothread(); 333 } 334 335 env->mip = (env->mip & ~mask) | (value & mask); 336 337 if (env->mip) { 338 cpu_interrupt(cs, CPU_INTERRUPT_HARD); 339 } else { 340 cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD); 341 } 342 343 if (locked) { 344 qemu_mutex_unlock_iothread(); 345 } 346 347 return old; 348 } 349 350 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t), 351 uint32_t arg) 352 { 353 env->rdtime_fn = fn; 354 env->rdtime_fn_arg = arg; 355 } 356 357 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv) 358 { 359 if (newpriv > PRV_M) { 360 g_assert_not_reached(); 361 } 362 if (newpriv == PRV_H) { 363 newpriv = PRV_U; 364 } 365 /* tlb_flush is unnecessary as mode is contained in mmu_idx */ 366 env->priv = newpriv; 367 368 /* 369 * Clear the load reservation - otherwise a reservation placed in one 370 * context/process can be used by another, resulting in an SC succeeding 371 * incorrectly. Version 2.2 of the ISA specification explicitly requires 372 * this behaviour, while later revisions say that the kernel "should" use 373 * an SC instruction to force the yielding of a load reservation on a 374 * preemptive context switch. As a result, do both. 375 */ 376 env->load_res = -1; 377 } 378 379 /* 380 * get_physical_address_pmp - check PMP permission for this physical address 381 * 382 * Match the PMP region and check permission for this physical address and it's 383 * TLB page. Returns 0 if the permission checking was successful 384 * 385 * @env: CPURISCVState 386 * @prot: The returned protection attributes 387 * @tlb_size: TLB page size containing addr. It could be modified after PMP 388 * permission checking. NULL if not set TLB page for addr. 389 * @addr: The physical address to be checked permission 390 * @access_type: The type of MMU access 391 * @mode: Indicates current privilege level. 392 */ 393 static int get_physical_address_pmp(CPURISCVState *env, int *prot, 394 target_ulong *tlb_size, hwaddr addr, 395 int size, MMUAccessType access_type, 396 int mode) 397 { 398 pmp_priv_t pmp_priv; 399 target_ulong tlb_size_pmp = 0; 400 401 if (!riscv_feature(env, RISCV_FEATURE_PMP)) { 402 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 403 return TRANSLATE_SUCCESS; 404 } 405 406 if (!pmp_hart_has_privs(env, addr, size, 1 << access_type, &pmp_priv, 407 mode)) { 408 *prot = 0; 409 return TRANSLATE_PMP_FAIL; 410 } 411 412 *prot = pmp_priv_to_page_prot(pmp_priv); 413 if (tlb_size != NULL) { 414 if (pmp_is_range_in_tlb(env, addr & ~(*tlb_size - 1), &tlb_size_pmp)) { 415 *tlb_size = tlb_size_pmp; 416 } 417 } 418 419 return TRANSLATE_SUCCESS; 420 } 421 422 /* get_physical_address - get the physical address for this virtual address 423 * 424 * Do a page table walk to obtain the physical address corresponding to a 425 * virtual address. Returns 0 if the translation was successful 426 * 427 * Adapted from Spike's mmu_t::translate and mmu_t::walk 428 * 429 * @env: CPURISCVState 430 * @physical: This will be set to the calculated physical address 431 * @prot: The returned protection attributes 432 * @addr: The virtual address to be translated 433 * @fault_pte_addr: If not NULL, this will be set to fault pte address 434 * when a error occurs on pte address translation. 435 * This will already be shifted to match htval. 436 * @access_type: The type of MMU access 437 * @mmu_idx: Indicates current privilege level 438 * @first_stage: Are we in first stage translation? 439 * Second stage is used for hypervisor guest translation 440 * @two_stage: Are we going to perform two stage translation 441 * @is_debug: Is this access from a debugger or the monitor? 442 */ 443 static int get_physical_address(CPURISCVState *env, hwaddr *physical, 444 int *prot, target_ulong addr, 445 target_ulong *fault_pte_addr, 446 int access_type, int mmu_idx, 447 bool first_stage, bool two_stage, 448 bool is_debug) 449 { 450 /* NOTE: the env->pc value visible here will not be 451 * correct, but the value visible to the exception handler 452 * (riscv_cpu_do_interrupt) is correct */ 453 MemTxResult res; 454 MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED; 455 int mode = mmu_idx & TB_FLAGS_PRIV_MMU_MASK; 456 bool use_background = false; 457 458 /* 459 * Check if we should use the background registers for the two 460 * stage translation. We don't need to check if we actually need 461 * two stage translation as that happened before this function 462 * was called. Background registers will be used if the guest has 463 * forced a two stage translation to be on (in HS or M mode). 464 */ 465 if (!riscv_cpu_virt_enabled(env) && two_stage) { 466 use_background = true; 467 } 468 469 /* MPRV does not affect the virtual-machine load/store 470 instructions, HLV, HLVX, and HSV. */ 471 if (riscv_cpu_two_stage_lookup(mmu_idx)) { 472 mode = get_field(env->hstatus, HSTATUS_SPVP); 473 } else if (mode == PRV_M && access_type != MMU_INST_FETCH) { 474 if (get_field(env->mstatus, MSTATUS_MPRV)) { 475 mode = get_field(env->mstatus, MSTATUS_MPP); 476 } 477 } 478 479 if (first_stage == false) { 480 /* We are in stage 2 translation, this is similar to stage 1. */ 481 /* Stage 2 is always taken as U-mode */ 482 mode = PRV_U; 483 } 484 485 if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) { 486 *physical = addr; 487 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 488 return TRANSLATE_SUCCESS; 489 } 490 491 *prot = 0; 492 493 hwaddr base; 494 int levels, ptidxbits, ptesize, vm, sum, mxr, widened; 495 496 if (first_stage == true) { 497 mxr = get_field(env->mstatus, MSTATUS_MXR); 498 } else { 499 mxr = get_field(env->vsstatus, MSTATUS_MXR); 500 } 501 502 if (first_stage == true) { 503 if (use_background) { 504 if (riscv_cpu_mxl(env) == MXL_RV32) { 505 base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT; 506 vm = get_field(env->vsatp, SATP32_MODE); 507 } else { 508 base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT; 509 vm = get_field(env->vsatp, SATP64_MODE); 510 } 511 } else { 512 if (riscv_cpu_mxl(env) == MXL_RV32) { 513 base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT; 514 vm = get_field(env->satp, SATP32_MODE); 515 } else { 516 base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT; 517 vm = get_field(env->satp, SATP64_MODE); 518 } 519 } 520 widened = 0; 521 } else { 522 if (riscv_cpu_mxl(env) == MXL_RV32) { 523 base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT; 524 vm = get_field(env->hgatp, SATP32_MODE); 525 } else { 526 base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT; 527 vm = get_field(env->hgatp, SATP64_MODE); 528 } 529 widened = 2; 530 } 531 /* status.SUM will be ignored if execute on background */ 532 sum = get_field(env->mstatus, MSTATUS_SUM) || use_background || is_debug; 533 switch (vm) { 534 case VM_1_10_SV32: 535 levels = 2; ptidxbits = 10; ptesize = 4; break; 536 case VM_1_10_SV39: 537 levels = 3; ptidxbits = 9; ptesize = 8; break; 538 case VM_1_10_SV48: 539 levels = 4; ptidxbits = 9; ptesize = 8; break; 540 case VM_1_10_SV57: 541 levels = 5; ptidxbits = 9; ptesize = 8; break; 542 case VM_1_10_MBARE: 543 *physical = addr; 544 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 545 return TRANSLATE_SUCCESS; 546 default: 547 g_assert_not_reached(); 548 } 549 550 CPUState *cs = env_cpu(env); 551 int va_bits = PGSHIFT + levels * ptidxbits + widened; 552 target_ulong mask, masked_msbs; 553 554 if (TARGET_LONG_BITS > (va_bits - 1)) { 555 mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1; 556 } else { 557 mask = 0; 558 } 559 masked_msbs = (addr >> (va_bits - 1)) & mask; 560 561 if (masked_msbs != 0 && masked_msbs != mask) { 562 return TRANSLATE_FAIL; 563 } 564 565 int ptshift = (levels - 1) * ptidxbits; 566 int i; 567 568 #if !TCG_OVERSIZED_GUEST 569 restart: 570 #endif 571 for (i = 0; i < levels; i++, ptshift -= ptidxbits) { 572 target_ulong idx; 573 if (i == 0) { 574 idx = (addr >> (PGSHIFT + ptshift)) & 575 ((1 << (ptidxbits + widened)) - 1); 576 } else { 577 idx = (addr >> (PGSHIFT + ptshift)) & 578 ((1 << ptidxbits) - 1); 579 } 580 581 /* check that physical address of PTE is legal */ 582 hwaddr pte_addr; 583 584 if (two_stage && first_stage) { 585 int vbase_prot; 586 hwaddr vbase; 587 588 /* Do the second stage translation on the base PTE address. */ 589 int vbase_ret = get_physical_address(env, &vbase, &vbase_prot, 590 base, NULL, MMU_DATA_LOAD, 591 mmu_idx, false, true, 592 is_debug); 593 594 if (vbase_ret != TRANSLATE_SUCCESS) { 595 if (fault_pte_addr) { 596 *fault_pte_addr = (base + idx * ptesize) >> 2; 597 } 598 return TRANSLATE_G_STAGE_FAIL; 599 } 600 601 pte_addr = vbase + idx * ptesize; 602 } else { 603 pte_addr = base + idx * ptesize; 604 } 605 606 int pmp_prot; 607 int pmp_ret = get_physical_address_pmp(env, &pmp_prot, NULL, pte_addr, 608 sizeof(target_ulong), 609 MMU_DATA_LOAD, PRV_S); 610 if (pmp_ret != TRANSLATE_SUCCESS) { 611 return TRANSLATE_PMP_FAIL; 612 } 613 614 target_ulong pte; 615 if (riscv_cpu_mxl(env) == MXL_RV32) { 616 pte = address_space_ldl(cs->as, pte_addr, attrs, &res); 617 } else { 618 pte = address_space_ldq(cs->as, pte_addr, attrs, &res); 619 } 620 621 if (res != MEMTX_OK) { 622 return TRANSLATE_FAIL; 623 } 624 625 hwaddr ppn = pte >> PTE_PPN_SHIFT; 626 627 if (!(pte & PTE_V)) { 628 /* Invalid PTE */ 629 return TRANSLATE_FAIL; 630 } else if (!(pte & (PTE_R | PTE_W | PTE_X))) { 631 /* Inner PTE, continue walking */ 632 base = ppn << PGSHIFT; 633 } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) { 634 /* Reserved leaf PTE flags: PTE_W */ 635 return TRANSLATE_FAIL; 636 } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) { 637 /* Reserved leaf PTE flags: PTE_W + PTE_X */ 638 return TRANSLATE_FAIL; 639 } else if ((pte & PTE_U) && ((mode != PRV_U) && 640 (!sum || access_type == MMU_INST_FETCH))) { 641 /* User PTE flags when not U mode and mstatus.SUM is not set, 642 or the access type is an instruction fetch */ 643 return TRANSLATE_FAIL; 644 } else if (!(pte & PTE_U) && (mode != PRV_S)) { 645 /* Supervisor PTE flags when not S mode */ 646 return TRANSLATE_FAIL; 647 } else if (ppn & ((1ULL << ptshift) - 1)) { 648 /* Misaligned PPN */ 649 return TRANSLATE_FAIL; 650 } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) || 651 ((pte & PTE_X) && mxr))) { 652 /* Read access check failed */ 653 return TRANSLATE_FAIL; 654 } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) { 655 /* Write access check failed */ 656 return TRANSLATE_FAIL; 657 } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) { 658 /* Fetch access check failed */ 659 return TRANSLATE_FAIL; 660 } else { 661 /* if necessary, set accessed and dirty bits. */ 662 target_ulong updated_pte = pte | PTE_A | 663 (access_type == MMU_DATA_STORE ? PTE_D : 0); 664 665 /* Page table updates need to be atomic with MTTCG enabled */ 666 if (updated_pte != pte) { 667 /* 668 * - if accessed or dirty bits need updating, and the PTE is 669 * in RAM, then we do so atomically with a compare and swap. 670 * - if the PTE is in IO space or ROM, then it can't be updated 671 * and we return TRANSLATE_FAIL. 672 * - if the PTE changed by the time we went to update it, then 673 * it is no longer valid and we must re-walk the page table. 674 */ 675 MemoryRegion *mr; 676 hwaddr l = sizeof(target_ulong), addr1; 677 mr = address_space_translate(cs->as, pte_addr, 678 &addr1, &l, false, MEMTXATTRS_UNSPECIFIED); 679 if (memory_region_is_ram(mr)) { 680 target_ulong *pte_pa = 681 qemu_map_ram_ptr(mr->ram_block, addr1); 682 #if TCG_OVERSIZED_GUEST 683 /* MTTCG is not enabled on oversized TCG guests so 684 * page table updates do not need to be atomic */ 685 *pte_pa = pte = updated_pte; 686 #else 687 target_ulong old_pte = 688 qatomic_cmpxchg(pte_pa, pte, updated_pte); 689 if (old_pte != pte) { 690 goto restart; 691 } else { 692 pte = updated_pte; 693 } 694 #endif 695 } else { 696 /* misconfigured PTE in ROM (AD bits are not preset) or 697 * PTE is in IO space and can't be updated atomically */ 698 return TRANSLATE_FAIL; 699 } 700 } 701 702 /* for superpage mappings, make a fake leaf PTE for the TLB's 703 benefit. */ 704 target_ulong vpn = addr >> PGSHIFT; 705 *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) | 706 (addr & ~TARGET_PAGE_MASK); 707 708 /* set permissions on the TLB entry */ 709 if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) { 710 *prot |= PAGE_READ; 711 } 712 if ((pte & PTE_X)) { 713 *prot |= PAGE_EXEC; 714 } 715 /* add write permission on stores or if the page is already dirty, 716 so that we TLB miss on later writes to update the dirty bit */ 717 if ((pte & PTE_W) && 718 (access_type == MMU_DATA_STORE || (pte & PTE_D))) { 719 *prot |= PAGE_WRITE; 720 } 721 return TRANSLATE_SUCCESS; 722 } 723 } 724 return TRANSLATE_FAIL; 725 } 726 727 static void raise_mmu_exception(CPURISCVState *env, target_ulong address, 728 MMUAccessType access_type, bool pmp_violation, 729 bool first_stage, bool two_stage) 730 { 731 CPUState *cs = env_cpu(env); 732 int page_fault_exceptions, vm; 733 uint64_t stap_mode; 734 735 if (riscv_cpu_mxl(env) == MXL_RV32) { 736 stap_mode = SATP32_MODE; 737 } else { 738 stap_mode = SATP64_MODE; 739 } 740 741 if (first_stage) { 742 vm = get_field(env->satp, stap_mode); 743 } else { 744 vm = get_field(env->hgatp, stap_mode); 745 } 746 747 page_fault_exceptions = vm != VM_1_10_MBARE && !pmp_violation; 748 749 switch (access_type) { 750 case MMU_INST_FETCH: 751 if (riscv_cpu_virt_enabled(env) && !first_stage) { 752 cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT; 753 } else { 754 cs->exception_index = page_fault_exceptions ? 755 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT; 756 } 757 break; 758 case MMU_DATA_LOAD: 759 if (two_stage && !first_stage) { 760 cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT; 761 } else { 762 cs->exception_index = page_fault_exceptions ? 763 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT; 764 } 765 break; 766 case MMU_DATA_STORE: 767 if (two_stage && !first_stage) { 768 cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT; 769 } else { 770 cs->exception_index = page_fault_exceptions ? 771 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT; 772 } 773 break; 774 default: 775 g_assert_not_reached(); 776 } 777 env->badaddr = address; 778 env->two_stage_lookup = two_stage; 779 } 780 781 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) 782 { 783 RISCVCPU *cpu = RISCV_CPU(cs); 784 CPURISCVState *env = &cpu->env; 785 hwaddr phys_addr; 786 int prot; 787 int mmu_idx = cpu_mmu_index(&cpu->env, false); 788 789 if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx, 790 true, riscv_cpu_virt_enabled(env), true)) { 791 return -1; 792 } 793 794 if (riscv_cpu_virt_enabled(env)) { 795 if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL, 796 0, mmu_idx, false, true, true)) { 797 return -1; 798 } 799 } 800 801 return phys_addr & TARGET_PAGE_MASK; 802 } 803 804 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, 805 vaddr addr, unsigned size, 806 MMUAccessType access_type, 807 int mmu_idx, MemTxAttrs attrs, 808 MemTxResult response, uintptr_t retaddr) 809 { 810 RISCVCPU *cpu = RISCV_CPU(cs); 811 CPURISCVState *env = &cpu->env; 812 813 if (access_type == MMU_DATA_STORE) { 814 cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT; 815 } else if (access_type == MMU_DATA_LOAD) { 816 cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT; 817 } else { 818 cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT; 819 } 820 821 env->badaddr = addr; 822 env->two_stage_lookup = riscv_cpu_virt_enabled(env) || 823 riscv_cpu_two_stage_lookup(mmu_idx); 824 riscv_raise_exception(&cpu->env, cs->exception_index, retaddr); 825 } 826 827 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, 828 MMUAccessType access_type, int mmu_idx, 829 uintptr_t retaddr) 830 { 831 RISCVCPU *cpu = RISCV_CPU(cs); 832 CPURISCVState *env = &cpu->env; 833 switch (access_type) { 834 case MMU_INST_FETCH: 835 cs->exception_index = RISCV_EXCP_INST_ADDR_MIS; 836 break; 837 case MMU_DATA_LOAD: 838 cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS; 839 break; 840 case MMU_DATA_STORE: 841 cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS; 842 break; 843 default: 844 g_assert_not_reached(); 845 } 846 env->badaddr = addr; 847 env->two_stage_lookup = riscv_cpu_virt_enabled(env) || 848 riscv_cpu_two_stage_lookup(mmu_idx); 849 riscv_raise_exception(env, cs->exception_index, retaddr); 850 } 851 852 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, 853 MMUAccessType access_type, int mmu_idx, 854 bool probe, uintptr_t retaddr) 855 { 856 RISCVCPU *cpu = RISCV_CPU(cs); 857 CPURISCVState *env = &cpu->env; 858 vaddr im_address; 859 hwaddr pa = 0; 860 int prot, prot2, prot_pmp; 861 bool pmp_violation = false; 862 bool first_stage_error = true; 863 bool two_stage_lookup = false; 864 int ret = TRANSLATE_FAIL; 865 int mode = mmu_idx; 866 /* default TLB page size */ 867 target_ulong tlb_size = TARGET_PAGE_SIZE; 868 869 env->guest_phys_fault_addr = 0; 870 871 qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n", 872 __func__, address, access_type, mmu_idx); 873 874 /* MPRV does not affect the virtual-machine load/store 875 instructions, HLV, HLVX, and HSV. */ 876 if (riscv_cpu_two_stage_lookup(mmu_idx)) { 877 mode = get_field(env->hstatus, HSTATUS_SPVP); 878 } else if (mode == PRV_M && access_type != MMU_INST_FETCH && 879 get_field(env->mstatus, MSTATUS_MPRV)) { 880 mode = get_field(env->mstatus, MSTATUS_MPP); 881 if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) { 882 two_stage_lookup = true; 883 } 884 } 885 886 if (riscv_cpu_virt_enabled(env) || 887 ((riscv_cpu_two_stage_lookup(mmu_idx) || two_stage_lookup) && 888 access_type != MMU_INST_FETCH)) { 889 /* Two stage lookup */ 890 ret = get_physical_address(env, &pa, &prot, address, 891 &env->guest_phys_fault_addr, access_type, 892 mmu_idx, true, true, false); 893 894 /* 895 * A G-stage exception may be triggered during two state lookup. 896 * And the env->guest_phys_fault_addr has already been set in 897 * get_physical_address(). 898 */ 899 if (ret == TRANSLATE_G_STAGE_FAIL) { 900 first_stage_error = false; 901 access_type = MMU_DATA_LOAD; 902 } 903 904 qemu_log_mask(CPU_LOG_MMU, 905 "%s 1st-stage address=%" VADDR_PRIx " ret %d physical " 906 TARGET_FMT_plx " prot %d\n", 907 __func__, address, ret, pa, prot); 908 909 if (ret == TRANSLATE_SUCCESS) { 910 /* Second stage lookup */ 911 im_address = pa; 912 913 ret = get_physical_address(env, &pa, &prot2, im_address, NULL, 914 access_type, mmu_idx, false, true, 915 false); 916 917 qemu_log_mask(CPU_LOG_MMU, 918 "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical " 919 TARGET_FMT_plx " prot %d\n", 920 __func__, im_address, ret, pa, prot2); 921 922 prot &= prot2; 923 924 if (ret == TRANSLATE_SUCCESS) { 925 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, 926 size, access_type, mode); 927 928 qemu_log_mask(CPU_LOG_MMU, 929 "%s PMP address=" TARGET_FMT_plx " ret %d prot" 930 " %d tlb_size " TARGET_FMT_lu "\n", 931 __func__, pa, ret, prot_pmp, tlb_size); 932 933 prot &= prot_pmp; 934 } 935 936 if (ret != TRANSLATE_SUCCESS) { 937 /* 938 * Guest physical address translation failed, this is a HS 939 * level exception 940 */ 941 first_stage_error = false; 942 env->guest_phys_fault_addr = (im_address | 943 (address & 944 (TARGET_PAGE_SIZE - 1))) >> 2; 945 } 946 } 947 } else { 948 /* Single stage lookup */ 949 ret = get_physical_address(env, &pa, &prot, address, NULL, 950 access_type, mmu_idx, true, false, false); 951 952 qemu_log_mask(CPU_LOG_MMU, 953 "%s address=%" VADDR_PRIx " ret %d physical " 954 TARGET_FMT_plx " prot %d\n", 955 __func__, address, ret, pa, prot); 956 957 if (ret == TRANSLATE_SUCCESS) { 958 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, 959 size, access_type, mode); 960 961 qemu_log_mask(CPU_LOG_MMU, 962 "%s PMP address=" TARGET_FMT_plx " ret %d prot" 963 " %d tlb_size " TARGET_FMT_lu "\n", 964 __func__, pa, ret, prot_pmp, tlb_size); 965 966 prot &= prot_pmp; 967 } 968 } 969 970 if (ret == TRANSLATE_PMP_FAIL) { 971 pmp_violation = true; 972 } 973 974 if (ret == TRANSLATE_SUCCESS) { 975 tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1), 976 prot, mmu_idx, tlb_size); 977 return true; 978 } else if (probe) { 979 return false; 980 } else { 981 raise_mmu_exception(env, address, access_type, pmp_violation, 982 first_stage_error, 983 riscv_cpu_virt_enabled(env) || 984 riscv_cpu_two_stage_lookup(mmu_idx)); 985 riscv_raise_exception(env, cs->exception_index, retaddr); 986 } 987 988 return true; 989 } 990 #endif /* !CONFIG_USER_ONLY */ 991 992 /* 993 * Handle Traps 994 * 995 * Adapted from Spike's processor_t::take_trap. 996 * 997 */ 998 void riscv_cpu_do_interrupt(CPUState *cs) 999 { 1000 #if !defined(CONFIG_USER_ONLY) 1001 1002 RISCVCPU *cpu = RISCV_CPU(cs); 1003 CPURISCVState *env = &cpu->env; 1004 bool write_gva = false; 1005 uint64_t s; 1006 1007 /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide 1008 * so we mask off the MSB and separate into trap type and cause. 1009 */ 1010 bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG); 1011 target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK; 1012 target_ulong deleg = async ? env->mideleg : env->medeleg; 1013 target_ulong tval = 0; 1014 target_ulong htval = 0; 1015 target_ulong mtval2 = 0; 1016 1017 if (cause == RISCV_EXCP_SEMIHOST) { 1018 if (env->priv >= PRV_S) { 1019 env->gpr[xA0] = do_common_semihosting(cs); 1020 env->pc += 4; 1021 return; 1022 } 1023 cause = RISCV_EXCP_BREAKPOINT; 1024 } 1025 1026 if (!async) { 1027 /* set tval to badaddr for traps with address information */ 1028 switch (cause) { 1029 case RISCV_EXCP_INST_GUEST_PAGE_FAULT: 1030 case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT: 1031 case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT: 1032 case RISCV_EXCP_INST_ADDR_MIS: 1033 case RISCV_EXCP_INST_ACCESS_FAULT: 1034 case RISCV_EXCP_LOAD_ADDR_MIS: 1035 case RISCV_EXCP_STORE_AMO_ADDR_MIS: 1036 case RISCV_EXCP_LOAD_ACCESS_FAULT: 1037 case RISCV_EXCP_STORE_AMO_ACCESS_FAULT: 1038 case RISCV_EXCP_INST_PAGE_FAULT: 1039 case RISCV_EXCP_LOAD_PAGE_FAULT: 1040 case RISCV_EXCP_STORE_PAGE_FAULT: 1041 write_gva = true; 1042 tval = env->badaddr; 1043 break; 1044 case RISCV_EXCP_ILLEGAL_INST: 1045 tval = env->bins; 1046 break; 1047 default: 1048 break; 1049 } 1050 /* ecall is dispatched as one cause so translate based on mode */ 1051 if (cause == RISCV_EXCP_U_ECALL) { 1052 assert(env->priv <= 3); 1053 1054 if (env->priv == PRV_M) { 1055 cause = RISCV_EXCP_M_ECALL; 1056 } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) { 1057 cause = RISCV_EXCP_VS_ECALL; 1058 } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) { 1059 cause = RISCV_EXCP_S_ECALL; 1060 } else if (env->priv == PRV_U) { 1061 cause = RISCV_EXCP_U_ECALL; 1062 } 1063 } 1064 } 1065 1066 trace_riscv_trap(env->mhartid, async, cause, env->pc, tval, 1067 riscv_cpu_get_trap_name(cause, async)); 1068 1069 qemu_log_mask(CPU_LOG_INT, 1070 "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", " 1071 "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n", 1072 __func__, env->mhartid, async, cause, env->pc, tval, 1073 riscv_cpu_get_trap_name(cause, async)); 1074 1075 if (env->priv <= PRV_S && 1076 cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) { 1077 /* handle the trap in S-mode */ 1078 if (riscv_has_ext(env, RVH)) { 1079 target_ulong hdeleg = async ? env->hideleg : env->hedeleg; 1080 1081 if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1)) { 1082 /* Trap to VS mode */ 1083 /* 1084 * See if we need to adjust cause. Yes if its VS mode interrupt 1085 * no if hypervisor has delegated one of hs mode's interrupt 1086 */ 1087 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT || 1088 cause == IRQ_VS_EXT) { 1089 cause = cause - 1; 1090 } 1091 write_gva = false; 1092 } else if (riscv_cpu_virt_enabled(env)) { 1093 /* Trap into HS mode, from virt */ 1094 riscv_cpu_swap_hypervisor_regs(env); 1095 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP, 1096 env->priv); 1097 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, 1098 riscv_cpu_virt_enabled(env)); 1099 1100 1101 htval = env->guest_phys_fault_addr; 1102 1103 riscv_cpu_set_virt_enabled(env, 0); 1104 } else { 1105 /* Trap into HS mode */ 1106 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false); 1107 htval = env->guest_phys_fault_addr; 1108 write_gva = false; 1109 } 1110 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva); 1111 } 1112 1113 s = env->mstatus; 1114 s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE)); 1115 s = set_field(s, MSTATUS_SPP, env->priv); 1116 s = set_field(s, MSTATUS_SIE, 0); 1117 env->mstatus = s; 1118 env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1)); 1119 env->sepc = env->pc; 1120 env->stval = tval; 1121 env->htval = htval; 1122 env->pc = (env->stvec >> 2 << 2) + 1123 ((async && (env->stvec & 3) == 1) ? cause * 4 : 0); 1124 riscv_cpu_set_mode(env, PRV_S); 1125 } else { 1126 /* handle the trap in M-mode */ 1127 if (riscv_has_ext(env, RVH)) { 1128 if (riscv_cpu_virt_enabled(env)) { 1129 riscv_cpu_swap_hypervisor_regs(env); 1130 } 1131 env->mstatus = set_field(env->mstatus, MSTATUS_MPV, 1132 riscv_cpu_virt_enabled(env)); 1133 if (riscv_cpu_virt_enabled(env) && tval) { 1134 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1); 1135 } 1136 1137 mtval2 = env->guest_phys_fault_addr; 1138 1139 /* Trapping to M mode, virt is disabled */ 1140 riscv_cpu_set_virt_enabled(env, 0); 1141 } 1142 1143 s = env->mstatus; 1144 s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE)); 1145 s = set_field(s, MSTATUS_MPP, env->priv); 1146 s = set_field(s, MSTATUS_MIE, 0); 1147 env->mstatus = s; 1148 env->mcause = cause | ~(((target_ulong)-1) >> async); 1149 env->mepc = env->pc; 1150 env->mtval = tval; 1151 env->mtval2 = mtval2; 1152 env->pc = (env->mtvec >> 2 << 2) + 1153 ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); 1154 riscv_cpu_set_mode(env, PRV_M); 1155 } 1156 1157 /* NOTE: it is not necessary to yield load reservations here. It is only 1158 * necessary for an SC from "another hart" to cause a load reservation 1159 * to be yielded. Refer to the memory consistency model section of the 1160 * RISC-V ISA Specification. 1161 */ 1162 1163 env->two_stage_lookup = false; 1164 #endif 1165 cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */ 1166 } 1167