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 uint32_t flags = 0; 73 74 *pc = env->pc; 75 *cs_base = 0; 76 77 if (riscv_has_ext(env, RVV)) { 78 /* 79 * If env->vl equals to VLMAX, we can use generic vector operation 80 * expanders (GVEC) to accerlate the vector operations. 81 * However, as LMUL could be a fractional number. The maximum 82 * vector size can be operated might be less than 8 bytes, 83 * which is not supported by GVEC. So we set vl_eq_vlmax flag to true 84 * only when maxsz >= 8 bytes. 85 */ 86 uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype); 87 uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW); 88 uint32_t maxsz = vlmax << sew; 89 bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) && 90 (maxsz >= 8); 91 flags = FIELD_DP32(flags, TB_FLAGS, VILL, 92 FIELD_EX64(env->vtype, VTYPE, VILL)); 93 flags = FIELD_DP32(flags, TB_FLAGS, SEW, sew); 94 flags = FIELD_DP32(flags, TB_FLAGS, LMUL, 95 FIELD_EX64(env->vtype, VTYPE, VLMUL)); 96 flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax); 97 } else { 98 flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1); 99 } 100 101 #ifdef CONFIG_USER_ONLY 102 flags |= TB_FLAGS_MSTATUS_FS; 103 flags |= TB_FLAGS_MSTATUS_VS; 104 #else 105 flags |= cpu_mmu_index(env, 0); 106 if (riscv_cpu_fp_enabled(env)) { 107 flags |= env->mstatus & MSTATUS_FS; 108 } 109 110 if (riscv_cpu_vector_enabled(env)) { 111 flags |= env->mstatus & MSTATUS_VS; 112 } 113 114 if (riscv_has_ext(env, RVH)) { 115 if (env->priv == PRV_M || 116 (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) || 117 (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) && 118 get_field(env->hstatus, HSTATUS_HU))) { 119 flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1); 120 } 121 122 flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS, 123 get_field(env->mstatus_hs, MSTATUS_FS)); 124 125 flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS, 126 get_field(env->mstatus_hs, MSTATUS_VS)); 127 } 128 if (riscv_has_ext(env, RVJ)) { 129 int priv = flags & TB_FLAGS_PRIV_MMU_MASK; 130 bool pm_enabled = false; 131 switch (priv) { 132 case PRV_U: 133 pm_enabled = env->mmte & U_PM_ENABLE; 134 break; 135 case PRV_S: 136 pm_enabled = env->mmte & S_PM_ENABLE; 137 break; 138 case PRV_M: 139 pm_enabled = env->mmte & M_PM_ENABLE; 140 break; 141 default: 142 g_assert_not_reached(); 143 } 144 flags = FIELD_DP32(flags, TB_FLAGS, PM_ENABLED, pm_enabled); 145 } 146 #endif 147 148 flags = FIELD_DP32(flags, TB_FLAGS, XL, cpu_get_xl(env)); 149 150 *pflags = flags; 151 } 152 153 #ifndef CONFIG_USER_ONLY 154 static int riscv_cpu_local_irq_pending(CPURISCVState *env) 155 { 156 target_ulong virt_enabled = riscv_cpu_virt_enabled(env); 157 158 target_ulong mstatus_mie = get_field(env->mstatus, MSTATUS_MIE); 159 target_ulong mstatus_sie = get_field(env->mstatus, MSTATUS_SIE); 160 161 target_ulong pending = env->mip & env->mie; 162 163 target_ulong mie = env->priv < PRV_M || 164 (env->priv == PRV_M && mstatus_mie); 165 target_ulong sie = env->priv < PRV_S || 166 (env->priv == PRV_S && mstatus_sie); 167 target_ulong hsie = virt_enabled || sie; 168 target_ulong vsie = virt_enabled && sie; 169 170 target_ulong irqs = 171 (pending & ~env->mideleg & -mie) | 172 (pending & env->mideleg & ~env->hideleg & -hsie) | 173 (pending & env->mideleg & env->hideleg & -vsie); 174 175 if (irqs) { 176 return ctz64(irqs); /* since non-zero */ 177 } else { 178 return RISCV_EXCP_NONE; /* indicates no pending interrupt */ 179 } 180 } 181 182 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request) 183 { 184 if (interrupt_request & CPU_INTERRUPT_HARD) { 185 RISCVCPU *cpu = RISCV_CPU(cs); 186 CPURISCVState *env = &cpu->env; 187 int interruptno = riscv_cpu_local_irq_pending(env); 188 if (interruptno >= 0) { 189 cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno; 190 riscv_cpu_do_interrupt(cs); 191 return true; 192 } 193 } 194 return false; 195 } 196 197 /* Return true is floating point support is currently enabled */ 198 bool riscv_cpu_fp_enabled(CPURISCVState *env) 199 { 200 if (env->mstatus & MSTATUS_FS) { 201 if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) { 202 return false; 203 } 204 return true; 205 } 206 207 return false; 208 } 209 210 /* Return true is vector support is currently enabled */ 211 bool riscv_cpu_vector_enabled(CPURISCVState *env) 212 { 213 if (env->mstatus & MSTATUS_VS) { 214 if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) { 215 return false; 216 } 217 return true; 218 } 219 220 return false; 221 } 222 223 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env) 224 { 225 uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS | 226 MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE | 227 MSTATUS64_UXL | MSTATUS_VS; 228 bool current_virt = riscv_cpu_virt_enabled(env); 229 230 g_assert(riscv_has_ext(env, RVH)); 231 232 if (current_virt) { 233 /* Current V=1 and we are about to change to V=0 */ 234 env->vsstatus = env->mstatus & mstatus_mask; 235 env->mstatus &= ~mstatus_mask; 236 env->mstatus |= env->mstatus_hs; 237 238 env->vstvec = env->stvec; 239 env->stvec = env->stvec_hs; 240 241 env->vsscratch = env->sscratch; 242 env->sscratch = env->sscratch_hs; 243 244 env->vsepc = env->sepc; 245 env->sepc = env->sepc_hs; 246 247 env->vscause = env->scause; 248 env->scause = env->scause_hs; 249 250 env->vstval = env->stval; 251 env->stval = env->stval_hs; 252 253 env->vsatp = env->satp; 254 env->satp = env->satp_hs; 255 } else { 256 /* Current V=0 and we are about to change to V=1 */ 257 env->mstatus_hs = env->mstatus & mstatus_mask; 258 env->mstatus &= ~mstatus_mask; 259 env->mstatus |= env->vsstatus; 260 261 env->stvec_hs = env->stvec; 262 env->stvec = env->vstvec; 263 264 env->sscratch_hs = env->sscratch; 265 env->sscratch = env->vsscratch; 266 267 env->sepc_hs = env->sepc; 268 env->sepc = env->vsepc; 269 270 env->scause_hs = env->scause; 271 env->scause = env->vscause; 272 273 env->stval_hs = env->stval; 274 env->stval = env->vstval; 275 276 env->satp_hs = env->satp; 277 env->satp = env->vsatp; 278 } 279 } 280 281 bool riscv_cpu_virt_enabled(CPURISCVState *env) 282 { 283 if (!riscv_has_ext(env, RVH)) { 284 return false; 285 } 286 287 return get_field(env->virt, VIRT_ONOFF); 288 } 289 290 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable) 291 { 292 if (!riscv_has_ext(env, RVH)) { 293 return; 294 } 295 296 /* Flush the TLB on all virt mode changes. */ 297 if (get_field(env->virt, VIRT_ONOFF) != enable) { 298 tlb_flush(env_cpu(env)); 299 } 300 301 env->virt = set_field(env->virt, VIRT_ONOFF, enable); 302 } 303 304 bool riscv_cpu_two_stage_lookup(int mmu_idx) 305 { 306 return mmu_idx & TB_FLAGS_PRIV_HYP_ACCESS_MASK; 307 } 308 309 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts) 310 { 311 CPURISCVState *env = &cpu->env; 312 if (env->miclaim & interrupts) { 313 return -1; 314 } else { 315 env->miclaim |= interrupts; 316 return 0; 317 } 318 } 319 320 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value) 321 { 322 CPURISCVState *env = &cpu->env; 323 CPUState *cs = CPU(cpu); 324 uint32_t old = env->mip; 325 bool locked = false; 326 327 if (!qemu_mutex_iothread_locked()) { 328 locked = true; 329 qemu_mutex_lock_iothread(); 330 } 331 332 env->mip = (env->mip & ~mask) | (value & mask); 333 334 if (env->mip) { 335 cpu_interrupt(cs, CPU_INTERRUPT_HARD); 336 } else { 337 cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD); 338 } 339 340 if (locked) { 341 qemu_mutex_unlock_iothread(); 342 } 343 344 return old; 345 } 346 347 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t), 348 uint32_t arg) 349 { 350 env->rdtime_fn = fn; 351 env->rdtime_fn_arg = arg; 352 } 353 354 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv) 355 { 356 if (newpriv > PRV_M) { 357 g_assert_not_reached(); 358 } 359 if (newpriv == PRV_H) { 360 newpriv = PRV_U; 361 } 362 /* tlb_flush is unnecessary as mode is contained in mmu_idx */ 363 env->priv = newpriv; 364 365 /* 366 * Clear the load reservation - otherwise a reservation placed in one 367 * context/process can be used by another, resulting in an SC succeeding 368 * incorrectly. Version 2.2 of the ISA specification explicitly requires 369 * this behaviour, while later revisions say that the kernel "should" use 370 * an SC instruction to force the yielding of a load reservation on a 371 * preemptive context switch. As a result, do both. 372 */ 373 env->load_res = -1; 374 } 375 376 /* 377 * get_physical_address_pmp - check PMP permission for this physical address 378 * 379 * Match the PMP region and check permission for this physical address and it's 380 * TLB page. Returns 0 if the permission checking was successful 381 * 382 * @env: CPURISCVState 383 * @prot: The returned protection attributes 384 * @tlb_size: TLB page size containing addr. It could be modified after PMP 385 * permission checking. NULL if not set TLB page for addr. 386 * @addr: The physical address to be checked permission 387 * @access_type: The type of MMU access 388 * @mode: Indicates current privilege level. 389 */ 390 static int get_physical_address_pmp(CPURISCVState *env, int *prot, 391 target_ulong *tlb_size, hwaddr addr, 392 int size, MMUAccessType access_type, 393 int mode) 394 { 395 pmp_priv_t pmp_priv; 396 target_ulong tlb_size_pmp = 0; 397 398 if (!riscv_feature(env, RISCV_FEATURE_PMP)) { 399 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 400 return TRANSLATE_SUCCESS; 401 } 402 403 if (!pmp_hart_has_privs(env, addr, size, 1 << access_type, &pmp_priv, 404 mode)) { 405 *prot = 0; 406 return TRANSLATE_PMP_FAIL; 407 } 408 409 *prot = pmp_priv_to_page_prot(pmp_priv); 410 if (tlb_size != NULL) { 411 if (pmp_is_range_in_tlb(env, addr & ~(*tlb_size - 1), &tlb_size_pmp)) { 412 *tlb_size = tlb_size_pmp; 413 } 414 } 415 416 return TRANSLATE_SUCCESS; 417 } 418 419 /* get_physical_address - get the physical address for this virtual address 420 * 421 * Do a page table walk to obtain the physical address corresponding to a 422 * virtual address. Returns 0 if the translation was successful 423 * 424 * Adapted from Spike's mmu_t::translate and mmu_t::walk 425 * 426 * @env: CPURISCVState 427 * @physical: This will be set to the calculated physical address 428 * @prot: The returned protection attributes 429 * @addr: The virtual address to be translated 430 * @fault_pte_addr: If not NULL, this will be set to fault pte address 431 * when a error occurs on pte address translation. 432 * This will already be shifted to match htval. 433 * @access_type: The type of MMU access 434 * @mmu_idx: Indicates current privilege level 435 * @first_stage: Are we in first stage translation? 436 * Second stage is used for hypervisor guest translation 437 * @two_stage: Are we going to perform two stage translation 438 * @is_debug: Is this access from a debugger or the monitor? 439 */ 440 static int get_physical_address(CPURISCVState *env, hwaddr *physical, 441 int *prot, target_ulong addr, 442 target_ulong *fault_pte_addr, 443 int access_type, int mmu_idx, 444 bool first_stage, bool two_stage, 445 bool is_debug) 446 { 447 /* NOTE: the env->pc value visible here will not be 448 * correct, but the value visible to the exception handler 449 * (riscv_cpu_do_interrupt) is correct */ 450 MemTxResult res; 451 MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED; 452 int mode = mmu_idx & TB_FLAGS_PRIV_MMU_MASK; 453 bool use_background = false; 454 455 /* 456 * Check if we should use the background registers for the two 457 * stage translation. We don't need to check if we actually need 458 * two stage translation as that happened before this function 459 * was called. Background registers will be used if the guest has 460 * forced a two stage translation to be on (in HS or M mode). 461 */ 462 if (!riscv_cpu_virt_enabled(env) && two_stage) { 463 use_background = true; 464 } 465 466 /* MPRV does not affect the virtual-machine load/store 467 instructions, HLV, HLVX, and HSV. */ 468 if (riscv_cpu_two_stage_lookup(mmu_idx)) { 469 mode = get_field(env->hstatus, HSTATUS_SPVP); 470 } else if (mode == PRV_M && access_type != MMU_INST_FETCH) { 471 if (get_field(env->mstatus, MSTATUS_MPRV)) { 472 mode = get_field(env->mstatus, MSTATUS_MPP); 473 } 474 } 475 476 if (first_stage == false) { 477 /* We are in stage 2 translation, this is similar to stage 1. */ 478 /* Stage 2 is always taken as U-mode */ 479 mode = PRV_U; 480 } 481 482 if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) { 483 *physical = addr; 484 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 485 return TRANSLATE_SUCCESS; 486 } 487 488 *prot = 0; 489 490 hwaddr base; 491 int levels, ptidxbits, ptesize, vm, sum, mxr, widened; 492 493 if (first_stage == true) { 494 mxr = get_field(env->mstatus, MSTATUS_MXR); 495 } else { 496 mxr = get_field(env->vsstatus, MSTATUS_MXR); 497 } 498 499 if (first_stage == true) { 500 if (use_background) { 501 if (riscv_cpu_mxl(env) == MXL_RV32) { 502 base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT; 503 vm = get_field(env->vsatp, SATP32_MODE); 504 } else { 505 base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT; 506 vm = get_field(env->vsatp, SATP64_MODE); 507 } 508 } else { 509 if (riscv_cpu_mxl(env) == MXL_RV32) { 510 base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT; 511 vm = get_field(env->satp, SATP32_MODE); 512 } else { 513 base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT; 514 vm = get_field(env->satp, SATP64_MODE); 515 } 516 } 517 widened = 0; 518 } else { 519 if (riscv_cpu_mxl(env) == MXL_RV32) { 520 base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT; 521 vm = get_field(env->hgatp, SATP32_MODE); 522 } else { 523 base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT; 524 vm = get_field(env->hgatp, SATP64_MODE); 525 } 526 widened = 2; 527 } 528 /* status.SUM will be ignored if execute on background */ 529 sum = get_field(env->mstatus, MSTATUS_SUM) || use_background || is_debug; 530 switch (vm) { 531 case VM_1_10_SV32: 532 levels = 2; ptidxbits = 10; ptesize = 4; break; 533 case VM_1_10_SV39: 534 levels = 3; ptidxbits = 9; ptesize = 8; break; 535 case VM_1_10_SV48: 536 levels = 4; ptidxbits = 9; ptesize = 8; break; 537 case VM_1_10_SV57: 538 levels = 5; ptidxbits = 9; ptesize = 8; break; 539 case VM_1_10_MBARE: 540 *physical = addr; 541 *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; 542 return TRANSLATE_SUCCESS; 543 default: 544 g_assert_not_reached(); 545 } 546 547 CPUState *cs = env_cpu(env); 548 int va_bits = PGSHIFT + levels * ptidxbits + widened; 549 target_ulong mask, masked_msbs; 550 551 if (TARGET_LONG_BITS > (va_bits - 1)) { 552 mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1; 553 } else { 554 mask = 0; 555 } 556 masked_msbs = (addr >> (va_bits - 1)) & mask; 557 558 if (masked_msbs != 0 && masked_msbs != mask) { 559 return TRANSLATE_FAIL; 560 } 561 562 int ptshift = (levels - 1) * ptidxbits; 563 int i; 564 565 #if !TCG_OVERSIZED_GUEST 566 restart: 567 #endif 568 for (i = 0; i < levels; i++, ptshift -= ptidxbits) { 569 target_ulong idx; 570 if (i == 0) { 571 idx = (addr >> (PGSHIFT + ptshift)) & 572 ((1 << (ptidxbits + widened)) - 1); 573 } else { 574 idx = (addr >> (PGSHIFT + ptshift)) & 575 ((1 << ptidxbits) - 1); 576 } 577 578 /* check that physical address of PTE is legal */ 579 hwaddr pte_addr; 580 581 if (two_stage && first_stage) { 582 int vbase_prot; 583 hwaddr vbase; 584 585 /* Do the second stage translation on the base PTE address. */ 586 int vbase_ret = get_physical_address(env, &vbase, &vbase_prot, 587 base, NULL, MMU_DATA_LOAD, 588 mmu_idx, false, true, 589 is_debug); 590 591 if (vbase_ret != TRANSLATE_SUCCESS) { 592 if (fault_pte_addr) { 593 *fault_pte_addr = (base + idx * ptesize) >> 2; 594 } 595 return TRANSLATE_G_STAGE_FAIL; 596 } 597 598 pte_addr = vbase + idx * ptesize; 599 } else { 600 pte_addr = base + idx * ptesize; 601 } 602 603 int pmp_prot; 604 int pmp_ret = get_physical_address_pmp(env, &pmp_prot, NULL, pte_addr, 605 sizeof(target_ulong), 606 MMU_DATA_LOAD, PRV_S); 607 if (pmp_ret != TRANSLATE_SUCCESS) { 608 return TRANSLATE_PMP_FAIL; 609 } 610 611 target_ulong pte; 612 if (riscv_cpu_mxl(env) == MXL_RV32) { 613 pte = address_space_ldl(cs->as, pte_addr, attrs, &res); 614 } else { 615 pte = address_space_ldq(cs->as, pte_addr, attrs, &res); 616 } 617 618 if (res != MEMTX_OK) { 619 return TRANSLATE_FAIL; 620 } 621 622 hwaddr ppn = pte >> PTE_PPN_SHIFT; 623 624 if (!(pte & PTE_V)) { 625 /* Invalid PTE */ 626 return TRANSLATE_FAIL; 627 } else if (!(pte & (PTE_R | PTE_W | PTE_X))) { 628 /* Inner PTE, continue walking */ 629 base = ppn << PGSHIFT; 630 } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) { 631 /* Reserved leaf PTE flags: PTE_W */ 632 return TRANSLATE_FAIL; 633 } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) { 634 /* Reserved leaf PTE flags: PTE_W + PTE_X */ 635 return TRANSLATE_FAIL; 636 } else if ((pte & PTE_U) && ((mode != PRV_U) && 637 (!sum || access_type == MMU_INST_FETCH))) { 638 /* User PTE flags when not U mode and mstatus.SUM is not set, 639 or the access type is an instruction fetch */ 640 return TRANSLATE_FAIL; 641 } else if (!(pte & PTE_U) && (mode != PRV_S)) { 642 /* Supervisor PTE flags when not S mode */ 643 return TRANSLATE_FAIL; 644 } else if (ppn & ((1ULL << ptshift) - 1)) { 645 /* Misaligned PPN */ 646 return TRANSLATE_FAIL; 647 } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) || 648 ((pte & PTE_X) && mxr))) { 649 /* Read access check failed */ 650 return TRANSLATE_FAIL; 651 } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) { 652 /* Write access check failed */ 653 return TRANSLATE_FAIL; 654 } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) { 655 /* Fetch access check failed */ 656 return TRANSLATE_FAIL; 657 } else { 658 /* if necessary, set accessed and dirty bits. */ 659 target_ulong updated_pte = pte | PTE_A | 660 (access_type == MMU_DATA_STORE ? PTE_D : 0); 661 662 /* Page table updates need to be atomic with MTTCG enabled */ 663 if (updated_pte != pte) { 664 /* 665 * - if accessed or dirty bits need updating, and the PTE is 666 * in RAM, then we do so atomically with a compare and swap. 667 * - if the PTE is in IO space or ROM, then it can't be updated 668 * and we return TRANSLATE_FAIL. 669 * - if the PTE changed by the time we went to update it, then 670 * it is no longer valid and we must re-walk the page table. 671 */ 672 MemoryRegion *mr; 673 hwaddr l = sizeof(target_ulong), addr1; 674 mr = address_space_translate(cs->as, pte_addr, 675 &addr1, &l, false, MEMTXATTRS_UNSPECIFIED); 676 if (memory_region_is_ram(mr)) { 677 target_ulong *pte_pa = 678 qemu_map_ram_ptr(mr->ram_block, addr1); 679 #if TCG_OVERSIZED_GUEST 680 /* MTTCG is not enabled on oversized TCG guests so 681 * page table updates do not need to be atomic */ 682 *pte_pa = pte = updated_pte; 683 #else 684 target_ulong old_pte = 685 qatomic_cmpxchg(pte_pa, pte, updated_pte); 686 if (old_pte != pte) { 687 goto restart; 688 } else { 689 pte = updated_pte; 690 } 691 #endif 692 } else { 693 /* misconfigured PTE in ROM (AD bits are not preset) or 694 * PTE is in IO space and can't be updated atomically */ 695 return TRANSLATE_FAIL; 696 } 697 } 698 699 /* for superpage mappings, make a fake leaf PTE for the TLB's 700 benefit. */ 701 target_ulong vpn = addr >> PGSHIFT; 702 *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) | 703 (addr & ~TARGET_PAGE_MASK); 704 705 /* set permissions on the TLB entry */ 706 if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) { 707 *prot |= PAGE_READ; 708 } 709 if ((pte & PTE_X)) { 710 *prot |= PAGE_EXEC; 711 } 712 /* add write permission on stores or if the page is already dirty, 713 so that we TLB miss on later writes to update the dirty bit */ 714 if ((pte & PTE_W) && 715 (access_type == MMU_DATA_STORE || (pte & PTE_D))) { 716 *prot |= PAGE_WRITE; 717 } 718 return TRANSLATE_SUCCESS; 719 } 720 } 721 return TRANSLATE_FAIL; 722 } 723 724 static void raise_mmu_exception(CPURISCVState *env, target_ulong address, 725 MMUAccessType access_type, bool pmp_violation, 726 bool first_stage, bool two_stage) 727 { 728 CPUState *cs = env_cpu(env); 729 int page_fault_exceptions, vm; 730 uint64_t stap_mode; 731 732 if (riscv_cpu_mxl(env) == MXL_RV32) { 733 stap_mode = SATP32_MODE; 734 } else { 735 stap_mode = SATP64_MODE; 736 } 737 738 if (first_stage) { 739 vm = get_field(env->satp, stap_mode); 740 } else { 741 vm = get_field(env->hgatp, stap_mode); 742 } 743 744 page_fault_exceptions = vm != VM_1_10_MBARE && !pmp_violation; 745 746 switch (access_type) { 747 case MMU_INST_FETCH: 748 if (riscv_cpu_virt_enabled(env) && !first_stage) { 749 cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT; 750 } else { 751 cs->exception_index = page_fault_exceptions ? 752 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT; 753 } 754 break; 755 case MMU_DATA_LOAD: 756 if (two_stage && !first_stage) { 757 cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT; 758 } else { 759 cs->exception_index = page_fault_exceptions ? 760 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT; 761 } 762 break; 763 case MMU_DATA_STORE: 764 if (two_stage && !first_stage) { 765 cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT; 766 } else { 767 cs->exception_index = page_fault_exceptions ? 768 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT; 769 } 770 break; 771 default: 772 g_assert_not_reached(); 773 } 774 env->badaddr = address; 775 env->two_stage_lookup = two_stage; 776 } 777 778 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) 779 { 780 RISCVCPU *cpu = RISCV_CPU(cs); 781 CPURISCVState *env = &cpu->env; 782 hwaddr phys_addr; 783 int prot; 784 int mmu_idx = cpu_mmu_index(&cpu->env, false); 785 786 if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx, 787 true, riscv_cpu_virt_enabled(env), true)) { 788 return -1; 789 } 790 791 if (riscv_cpu_virt_enabled(env)) { 792 if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL, 793 0, mmu_idx, false, true, true)) { 794 return -1; 795 } 796 } 797 798 return phys_addr & TARGET_PAGE_MASK; 799 } 800 801 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, 802 vaddr addr, unsigned size, 803 MMUAccessType access_type, 804 int mmu_idx, MemTxAttrs attrs, 805 MemTxResult response, uintptr_t retaddr) 806 { 807 RISCVCPU *cpu = RISCV_CPU(cs); 808 CPURISCVState *env = &cpu->env; 809 810 if (access_type == MMU_DATA_STORE) { 811 cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT; 812 } else if (access_type == MMU_DATA_LOAD) { 813 cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT; 814 } else { 815 cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT; 816 } 817 818 env->badaddr = addr; 819 env->two_stage_lookup = riscv_cpu_virt_enabled(env) || 820 riscv_cpu_two_stage_lookup(mmu_idx); 821 riscv_raise_exception(&cpu->env, cs->exception_index, retaddr); 822 } 823 824 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, 825 MMUAccessType access_type, int mmu_idx, 826 uintptr_t retaddr) 827 { 828 RISCVCPU *cpu = RISCV_CPU(cs); 829 CPURISCVState *env = &cpu->env; 830 switch (access_type) { 831 case MMU_INST_FETCH: 832 cs->exception_index = RISCV_EXCP_INST_ADDR_MIS; 833 break; 834 case MMU_DATA_LOAD: 835 cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS; 836 break; 837 case MMU_DATA_STORE: 838 cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS; 839 break; 840 default: 841 g_assert_not_reached(); 842 } 843 env->badaddr = addr; 844 env->two_stage_lookup = riscv_cpu_virt_enabled(env) || 845 riscv_cpu_two_stage_lookup(mmu_idx); 846 riscv_raise_exception(env, cs->exception_index, retaddr); 847 } 848 849 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, 850 MMUAccessType access_type, int mmu_idx, 851 bool probe, uintptr_t retaddr) 852 { 853 RISCVCPU *cpu = RISCV_CPU(cs); 854 CPURISCVState *env = &cpu->env; 855 vaddr im_address; 856 hwaddr pa = 0; 857 int prot, prot2, prot_pmp; 858 bool pmp_violation = false; 859 bool first_stage_error = true; 860 bool two_stage_lookup = false; 861 int ret = TRANSLATE_FAIL; 862 int mode = mmu_idx; 863 /* default TLB page size */ 864 target_ulong tlb_size = TARGET_PAGE_SIZE; 865 866 env->guest_phys_fault_addr = 0; 867 868 qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n", 869 __func__, address, access_type, mmu_idx); 870 871 /* MPRV does not affect the virtual-machine load/store 872 instructions, HLV, HLVX, and HSV. */ 873 if (riscv_cpu_two_stage_lookup(mmu_idx)) { 874 mode = get_field(env->hstatus, HSTATUS_SPVP); 875 } else if (mode == PRV_M && access_type != MMU_INST_FETCH && 876 get_field(env->mstatus, MSTATUS_MPRV)) { 877 mode = get_field(env->mstatus, MSTATUS_MPP); 878 if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) { 879 two_stage_lookup = true; 880 } 881 } 882 883 if (riscv_cpu_virt_enabled(env) || 884 ((riscv_cpu_two_stage_lookup(mmu_idx) || two_stage_lookup) && 885 access_type != MMU_INST_FETCH)) { 886 /* Two stage lookup */ 887 ret = get_physical_address(env, &pa, &prot, address, 888 &env->guest_phys_fault_addr, access_type, 889 mmu_idx, true, true, false); 890 891 /* 892 * A G-stage exception may be triggered during two state lookup. 893 * And the env->guest_phys_fault_addr has already been set in 894 * get_physical_address(). 895 */ 896 if (ret == TRANSLATE_G_STAGE_FAIL) { 897 first_stage_error = false; 898 access_type = MMU_DATA_LOAD; 899 } 900 901 qemu_log_mask(CPU_LOG_MMU, 902 "%s 1st-stage address=%" VADDR_PRIx " ret %d physical " 903 TARGET_FMT_plx " prot %d\n", 904 __func__, address, ret, pa, prot); 905 906 if (ret == TRANSLATE_SUCCESS) { 907 /* Second stage lookup */ 908 im_address = pa; 909 910 ret = get_physical_address(env, &pa, &prot2, im_address, NULL, 911 access_type, mmu_idx, false, true, 912 false); 913 914 qemu_log_mask(CPU_LOG_MMU, 915 "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical " 916 TARGET_FMT_plx " prot %d\n", 917 __func__, im_address, ret, pa, prot2); 918 919 prot &= prot2; 920 921 if (ret == TRANSLATE_SUCCESS) { 922 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, 923 size, access_type, mode); 924 925 qemu_log_mask(CPU_LOG_MMU, 926 "%s PMP address=" TARGET_FMT_plx " ret %d prot" 927 " %d tlb_size " TARGET_FMT_lu "\n", 928 __func__, pa, ret, prot_pmp, tlb_size); 929 930 prot &= prot_pmp; 931 } 932 933 if (ret != TRANSLATE_SUCCESS) { 934 /* 935 * Guest physical address translation failed, this is a HS 936 * level exception 937 */ 938 first_stage_error = false; 939 env->guest_phys_fault_addr = (im_address | 940 (address & 941 (TARGET_PAGE_SIZE - 1))) >> 2; 942 } 943 } 944 } else { 945 /* Single stage lookup */ 946 ret = get_physical_address(env, &pa, &prot, address, NULL, 947 access_type, mmu_idx, true, false, false); 948 949 qemu_log_mask(CPU_LOG_MMU, 950 "%s address=%" VADDR_PRIx " ret %d physical " 951 TARGET_FMT_plx " prot %d\n", 952 __func__, address, ret, pa, prot); 953 954 if (ret == TRANSLATE_SUCCESS) { 955 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, 956 size, access_type, mode); 957 958 qemu_log_mask(CPU_LOG_MMU, 959 "%s PMP address=" TARGET_FMT_plx " ret %d prot" 960 " %d tlb_size " TARGET_FMT_lu "\n", 961 __func__, pa, ret, prot_pmp, tlb_size); 962 963 prot &= prot_pmp; 964 } 965 } 966 967 if (ret == TRANSLATE_PMP_FAIL) { 968 pmp_violation = true; 969 } 970 971 if (ret == TRANSLATE_SUCCESS) { 972 tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1), 973 prot, mmu_idx, tlb_size); 974 return true; 975 } else if (probe) { 976 return false; 977 } else { 978 raise_mmu_exception(env, address, access_type, pmp_violation, 979 first_stage_error, 980 riscv_cpu_virt_enabled(env) || 981 riscv_cpu_two_stage_lookup(mmu_idx)); 982 riscv_raise_exception(env, cs->exception_index, retaddr); 983 } 984 985 return true; 986 } 987 #endif /* !CONFIG_USER_ONLY */ 988 989 /* 990 * Handle Traps 991 * 992 * Adapted from Spike's processor_t::take_trap. 993 * 994 */ 995 void riscv_cpu_do_interrupt(CPUState *cs) 996 { 997 #if !defined(CONFIG_USER_ONLY) 998 999 RISCVCPU *cpu = RISCV_CPU(cs); 1000 CPURISCVState *env = &cpu->env; 1001 uint64_t s; 1002 1003 /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide 1004 * so we mask off the MSB and separate into trap type and cause. 1005 */ 1006 bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG); 1007 target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK; 1008 target_ulong deleg = async ? env->mideleg : env->medeleg; 1009 bool write_tval = false; 1010 target_ulong tval = 0; 1011 target_ulong htval = 0; 1012 target_ulong mtval2 = 0; 1013 1014 if (cause == RISCV_EXCP_SEMIHOST) { 1015 if (env->priv >= PRV_S) { 1016 env->gpr[xA0] = do_common_semihosting(cs); 1017 env->pc += 4; 1018 return; 1019 } 1020 cause = RISCV_EXCP_BREAKPOINT; 1021 } 1022 1023 if (!async) { 1024 /* set tval to badaddr for traps with address information */ 1025 switch (cause) { 1026 case RISCV_EXCP_INST_GUEST_PAGE_FAULT: 1027 case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT: 1028 case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT: 1029 case RISCV_EXCP_INST_ADDR_MIS: 1030 case RISCV_EXCP_INST_ACCESS_FAULT: 1031 case RISCV_EXCP_LOAD_ADDR_MIS: 1032 case RISCV_EXCP_STORE_AMO_ADDR_MIS: 1033 case RISCV_EXCP_LOAD_ACCESS_FAULT: 1034 case RISCV_EXCP_STORE_AMO_ACCESS_FAULT: 1035 case RISCV_EXCP_INST_PAGE_FAULT: 1036 case RISCV_EXCP_LOAD_PAGE_FAULT: 1037 case RISCV_EXCP_STORE_PAGE_FAULT: 1038 write_tval = true; 1039 tval = env->badaddr; 1040 break; 1041 default: 1042 break; 1043 } 1044 /* ecall is dispatched as one cause so translate based on mode */ 1045 if (cause == RISCV_EXCP_U_ECALL) { 1046 assert(env->priv <= 3); 1047 1048 if (env->priv == PRV_M) { 1049 cause = RISCV_EXCP_M_ECALL; 1050 } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) { 1051 cause = RISCV_EXCP_VS_ECALL; 1052 } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) { 1053 cause = RISCV_EXCP_S_ECALL; 1054 } else if (env->priv == PRV_U) { 1055 cause = RISCV_EXCP_U_ECALL; 1056 } 1057 } 1058 } 1059 1060 trace_riscv_trap(env->mhartid, async, cause, env->pc, tval, 1061 riscv_cpu_get_trap_name(cause, async)); 1062 1063 qemu_log_mask(CPU_LOG_INT, 1064 "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", " 1065 "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n", 1066 __func__, env->mhartid, async, cause, env->pc, tval, 1067 riscv_cpu_get_trap_name(cause, async)); 1068 1069 if (env->priv <= PRV_S && 1070 cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) { 1071 /* handle the trap in S-mode */ 1072 if (riscv_has_ext(env, RVH)) { 1073 target_ulong hdeleg = async ? env->hideleg : env->hedeleg; 1074 1075 if (env->two_stage_lookup && write_tval) { 1076 /* 1077 * If we are writing a guest virtual address to stval, set 1078 * this to 1. If we are trapping to VS we will set this to 0 1079 * later. 1080 */ 1081 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 1); 1082 } else { 1083 /* For other HS-mode traps, we set this to 0. */ 1084 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0); 1085 } 1086 1087 if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1)) { 1088 /* Trap to VS mode */ 1089 /* 1090 * See if we need to adjust cause. Yes if its VS mode interrupt 1091 * no if hypervisor has delegated one of hs mode's interrupt 1092 */ 1093 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT || 1094 cause == IRQ_VS_EXT) { 1095 cause = cause - 1; 1096 } 1097 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0); 1098 } else if (riscv_cpu_virt_enabled(env)) { 1099 /* Trap into HS mode, from virt */ 1100 riscv_cpu_swap_hypervisor_regs(env); 1101 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP, 1102 env->priv); 1103 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, 1104 riscv_cpu_virt_enabled(env)); 1105 1106 htval = env->guest_phys_fault_addr; 1107 1108 riscv_cpu_set_virt_enabled(env, 0); 1109 } else { 1110 /* Trap into HS mode */ 1111 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false); 1112 htval = env->guest_phys_fault_addr; 1113 } 1114 } 1115 1116 s = env->mstatus; 1117 s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE)); 1118 s = set_field(s, MSTATUS_SPP, env->priv); 1119 s = set_field(s, MSTATUS_SIE, 0); 1120 env->mstatus = s; 1121 env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1)); 1122 env->sepc = env->pc; 1123 env->stval = tval; 1124 env->htval = htval; 1125 env->pc = (env->stvec >> 2 << 2) + 1126 ((async && (env->stvec & 3) == 1) ? cause * 4 : 0); 1127 riscv_cpu_set_mode(env, PRV_S); 1128 } else { 1129 /* handle the trap in M-mode */ 1130 if (riscv_has_ext(env, RVH)) { 1131 if (riscv_cpu_virt_enabled(env)) { 1132 riscv_cpu_swap_hypervisor_regs(env); 1133 } 1134 env->mstatus = set_field(env->mstatus, MSTATUS_MPV, 1135 riscv_cpu_virt_enabled(env)); 1136 if (riscv_cpu_virt_enabled(env) && tval) { 1137 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1); 1138 } 1139 1140 mtval2 = env->guest_phys_fault_addr; 1141 1142 /* Trapping to M mode, virt is disabled */ 1143 riscv_cpu_set_virt_enabled(env, 0); 1144 } 1145 1146 s = env->mstatus; 1147 s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE)); 1148 s = set_field(s, MSTATUS_MPP, env->priv); 1149 s = set_field(s, MSTATUS_MIE, 0); 1150 env->mstatus = s; 1151 env->mcause = cause | ~(((target_ulong)-1) >> async); 1152 env->mepc = env->pc; 1153 env->mtval = tval; 1154 env->mtval2 = mtval2; 1155 env->pc = (env->mtvec >> 2 << 2) + 1156 ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); 1157 riscv_cpu_set_mode(env, PRV_M); 1158 } 1159 1160 /* NOTE: it is not necessary to yield load reservations here. It is only 1161 * necessary for an SC from "another hart" to cause a load reservation 1162 * to be yielded. Refer to the memory consistency model section of the 1163 * RISC-V ISA Specification. 1164 */ 1165 1166 env->two_stage_lookup = false; 1167 #endif 1168 cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */ 1169 } 1170