xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision a47ef6e9)
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 
28 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
29 {
30 #ifdef CONFIG_USER_ONLY
31     return 0;
32 #else
33     return env->priv;
34 #endif
35 }
36 
37 #ifndef CONFIG_USER_ONLY
38 static int riscv_cpu_local_irq_pending(CPURISCVState *env)
39 {
40     target_ulong irqs;
41 
42     target_ulong mstatus_mie = get_field(env->mstatus, MSTATUS_MIE);
43     target_ulong mstatus_sie = get_field(env->mstatus, MSTATUS_SIE);
44     target_ulong hs_mstatus_sie = get_field(env->mstatus_hs, MSTATUS_SIE);
45 
46     target_ulong pending = env->mip & env->mie &
47                                ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
48     target_ulong vspending = (env->mip & env->mie &
49                               (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP));
50 
51     target_ulong mie    = env->priv < PRV_M ||
52                           (env->priv == PRV_M && mstatus_mie);
53     target_ulong sie    = env->priv < PRV_S ||
54                           (env->priv == PRV_S && mstatus_sie);
55     target_ulong hs_sie = env->priv < PRV_S ||
56                           (env->priv == PRV_S && hs_mstatus_sie);
57 
58     if (riscv_cpu_virt_enabled(env)) {
59         target_ulong pending_hs_irq = pending & -hs_sie;
60 
61         if (pending_hs_irq) {
62             riscv_cpu_set_force_hs_excep(env, FORCE_HS_EXCEP);
63             return ctz64(pending_hs_irq);
64         }
65 
66         pending = vspending;
67     }
68 
69     irqs = (pending & ~env->mideleg & -mie) | (pending &  env->mideleg & -sie);
70 
71     if (irqs) {
72         return ctz64(irqs); /* since non-zero */
73     } else {
74         return EXCP_NONE; /* indicates no pending interrupt */
75     }
76 }
77 #endif
78 
79 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
80 {
81 #if !defined(CONFIG_USER_ONLY)
82     if (interrupt_request & CPU_INTERRUPT_HARD) {
83         RISCVCPU *cpu = RISCV_CPU(cs);
84         CPURISCVState *env = &cpu->env;
85         int interruptno = riscv_cpu_local_irq_pending(env);
86         if (interruptno >= 0) {
87             cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno;
88             riscv_cpu_do_interrupt(cs);
89             return true;
90         }
91     }
92 #endif
93     return false;
94 }
95 
96 #if !defined(CONFIG_USER_ONLY)
97 
98 /* Return true is floating point support is currently enabled */
99 bool riscv_cpu_fp_enabled(CPURISCVState *env)
100 {
101     if (env->mstatus & MSTATUS_FS) {
102         if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) {
103             return false;
104         }
105         return true;
106     }
107 
108     return false;
109 }
110 
111 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
112 {
113     target_ulong mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS |
114                                 MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE;
115     bool current_virt = riscv_cpu_virt_enabled(env);
116 
117     g_assert(riscv_has_ext(env, RVH));
118 
119 #if defined(TARGET_RISCV64)
120     mstatus_mask |= MSTATUS64_UXL;
121 #endif
122 
123     if (current_virt) {
124         /* Current V=1 and we are about to change to V=0 */
125         env->vsstatus = env->mstatus & mstatus_mask;
126         env->mstatus &= ~mstatus_mask;
127         env->mstatus |= env->mstatus_hs;
128 
129 #if defined(TARGET_RISCV32)
130         env->vsstatush = env->mstatush;
131         env->mstatush |= env->mstatush_hs;
132 #endif
133 
134         env->vstvec = env->stvec;
135         env->stvec = env->stvec_hs;
136 
137         env->vsscratch = env->sscratch;
138         env->sscratch = env->sscratch_hs;
139 
140         env->vsepc = env->sepc;
141         env->sepc = env->sepc_hs;
142 
143         env->vscause = env->scause;
144         env->scause = env->scause_hs;
145 
146         env->vstval = env->sbadaddr;
147         env->sbadaddr = env->stval_hs;
148 
149         env->vsatp = env->satp;
150         env->satp = env->satp_hs;
151     } else {
152         /* Current V=0 and we are about to change to V=1 */
153         env->mstatus_hs = env->mstatus & mstatus_mask;
154         env->mstatus &= ~mstatus_mask;
155         env->mstatus |= env->vsstatus;
156 
157 #if defined(TARGET_RISCV32)
158         env->mstatush_hs = env->mstatush;
159         env->mstatush |= env->vsstatush;
160 #endif
161 
162         env->stvec_hs = env->stvec;
163         env->stvec = env->vstvec;
164 
165         env->sscratch_hs = env->sscratch;
166         env->sscratch = env->vsscratch;
167 
168         env->sepc_hs = env->sepc;
169         env->sepc = env->vsepc;
170 
171         env->scause_hs = env->scause;
172         env->scause = env->vscause;
173 
174         env->stval_hs = env->sbadaddr;
175         env->sbadaddr = env->vstval;
176 
177         env->satp_hs = env->satp;
178         env->satp = env->vsatp;
179     }
180 }
181 
182 bool riscv_cpu_virt_enabled(CPURISCVState *env)
183 {
184     if (!riscv_has_ext(env, RVH)) {
185         return false;
186     }
187 
188     return get_field(env->virt, VIRT_ONOFF);
189 }
190 
191 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
192 {
193     if (!riscv_has_ext(env, RVH)) {
194         return;
195     }
196 
197     /* Flush the TLB on all virt mode changes. */
198     if (get_field(env->virt, VIRT_ONOFF) != enable) {
199         tlb_flush(env_cpu(env));
200     }
201 
202     env->virt = set_field(env->virt, VIRT_ONOFF, enable);
203 }
204 
205 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env)
206 {
207     if (!riscv_has_ext(env, RVH)) {
208         return false;
209     }
210 
211     return get_field(env->virt, FORCE_HS_EXCEP);
212 }
213 
214 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable)
215 {
216     if (!riscv_has_ext(env, RVH)) {
217         return;
218     }
219 
220     env->virt = set_field(env->virt, FORCE_HS_EXCEP, enable);
221 }
222 
223 bool riscv_cpu_two_stage_lookup(CPURISCVState *env)
224 {
225     if (!riscv_has_ext(env, RVH)) {
226         return false;
227     }
228 
229     return get_field(env->virt, HS_TWO_STAGE);
230 }
231 
232 void riscv_cpu_set_two_stage_lookup(CPURISCVState *env, bool enable)
233 {
234     if (!riscv_has_ext(env, RVH)) {
235         return;
236     }
237 
238     env->virt = set_field(env->virt, HS_TWO_STAGE, enable);
239 }
240 
241 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts)
242 {
243     CPURISCVState *env = &cpu->env;
244     if (env->miclaim & interrupts) {
245         return -1;
246     } else {
247         env->miclaim |= interrupts;
248         return 0;
249     }
250 }
251 
252 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value)
253 {
254     CPURISCVState *env = &cpu->env;
255     CPUState *cs = CPU(cpu);
256     uint32_t old = env->mip;
257     bool locked = false;
258 
259     if (!qemu_mutex_iothread_locked()) {
260         locked = true;
261         qemu_mutex_lock_iothread();
262     }
263 
264     env->mip = (env->mip & ~mask) | (value & mask);
265 
266     if (env->mip) {
267         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
268     } else {
269         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
270     }
271 
272     if (locked) {
273         qemu_mutex_unlock_iothread();
274     }
275 
276     return old;
277 }
278 
279 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
280                              uint32_t arg)
281 {
282     env->rdtime_fn = fn;
283     env->rdtime_fn_arg = arg;
284 }
285 
286 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv)
287 {
288     if (newpriv > PRV_M) {
289         g_assert_not_reached();
290     }
291     if (newpriv == PRV_H) {
292         newpriv = PRV_U;
293     }
294     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
295     env->priv = newpriv;
296 
297     /*
298      * Clear the load reservation - otherwise a reservation placed in one
299      * context/process can be used by another, resulting in an SC succeeding
300      * incorrectly. Version 2.2 of the ISA specification explicitly requires
301      * this behaviour, while later revisions say that the kernel "should" use
302      * an SC instruction to force the yielding of a load reservation on a
303      * preemptive context switch. As a result, do both.
304      */
305     env->load_res = -1;
306 }
307 
308 /* get_physical_address - get the physical address for this virtual address
309  *
310  * Do a page table walk to obtain the physical address corresponding to a
311  * virtual address. Returns 0 if the translation was successful
312  *
313  * Adapted from Spike's mmu_t::translate and mmu_t::walk
314  *
315  * @env: CPURISCVState
316  * @physical: This will be set to the calculated physical address
317  * @prot: The returned protection attributes
318  * @addr: The virtual address to be translated
319  * @access_type: The type of MMU access
320  * @mmu_idx: Indicates current privilege level
321  * @first_stage: Are we in first stage translation?
322  *               Second stage is used for hypervisor guest translation
323  * @two_stage: Are we going to perform two stage translation
324  */
325 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
326                                 int *prot, target_ulong addr,
327                                 int access_type, int mmu_idx,
328                                 bool first_stage, bool two_stage)
329 {
330     /* NOTE: the env->pc value visible here will not be
331      * correct, but the value visible to the exception handler
332      * (riscv_cpu_do_interrupt) is correct */
333     MemTxResult res;
334     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
335     int mode = mmu_idx;
336     bool use_background = false;
337 
338     /*
339      * Check if we should use the background registers for the two
340      * stage translation. We don't need to check if we actually need
341      * two stage translation as that happened before this function
342      * was called. Background registers will be used if the guest has
343      * forced a two stage translation to be on (in HS or M mode).
344      */
345     if (riscv_cpu_two_stage_lookup(env) && access_type != MMU_INST_FETCH) {
346         use_background = true;
347     }
348 
349     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
350         if (get_field(env->mstatus, MSTATUS_MPRV)) {
351             mode = get_field(env->mstatus, MSTATUS_MPP);
352         }
353     }
354 
355     if (first_stage == false) {
356         /* We are in stage 2 translation, this is similar to stage 1. */
357         /* Stage 2 is always taken as U-mode */
358         mode = PRV_U;
359     }
360 
361     if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) {
362         *physical = addr;
363         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
364         return TRANSLATE_SUCCESS;
365     }
366 
367     *prot = 0;
368 
369     hwaddr base;
370     int levels, ptidxbits, ptesize, vm, sum, mxr, widened;
371 
372     if (first_stage == true) {
373         mxr = get_field(env->mstatus, MSTATUS_MXR);
374     } else {
375         mxr = get_field(env->vsstatus, MSTATUS_MXR);
376     }
377 
378     if (first_stage == true) {
379         if (use_background) {
380             base = (hwaddr)get_field(env->vsatp, SATP_PPN) << PGSHIFT;
381             vm = get_field(env->vsatp, SATP_MODE);
382         } else {
383             base = (hwaddr)get_field(env->satp, SATP_PPN) << PGSHIFT;
384             vm = get_field(env->satp, SATP_MODE);
385         }
386         widened = 0;
387     } else {
388         base = (hwaddr)get_field(env->hgatp, HGATP_PPN) << PGSHIFT;
389         vm = get_field(env->hgatp, HGATP_MODE);
390         widened = 2;
391     }
392     sum = get_field(env->mstatus, MSTATUS_SUM);
393     switch (vm) {
394     case VM_1_10_SV32:
395       levels = 2; ptidxbits = 10; ptesize = 4; break;
396     case VM_1_10_SV39:
397       levels = 3; ptidxbits = 9; ptesize = 8; break;
398     case VM_1_10_SV48:
399       levels = 4; ptidxbits = 9; ptesize = 8; break;
400     case VM_1_10_SV57:
401       levels = 5; ptidxbits = 9; ptesize = 8; break;
402     case VM_1_10_MBARE:
403         *physical = addr;
404         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
405         return TRANSLATE_SUCCESS;
406     default:
407       g_assert_not_reached();
408     }
409 
410     CPUState *cs = env_cpu(env);
411     int va_bits = PGSHIFT + levels * ptidxbits + widened;
412     target_ulong mask, masked_msbs;
413 
414     if (TARGET_LONG_BITS > (va_bits - 1)) {
415         mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1;
416     } else {
417         mask = 0;
418     }
419     masked_msbs = (addr >> (va_bits - 1)) & mask;
420 
421     if (masked_msbs != 0 && masked_msbs != mask) {
422         return TRANSLATE_FAIL;
423     }
424 
425     int ptshift = (levels - 1) * ptidxbits;
426     int i;
427 
428 #if !TCG_OVERSIZED_GUEST
429 restart:
430 #endif
431     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
432         target_ulong idx;
433         if (i == 0) {
434             idx = (addr >> (PGSHIFT + ptshift)) &
435                            ((1 << (ptidxbits + widened)) - 1);
436         } else {
437             idx = (addr >> (PGSHIFT + ptshift)) &
438                            ((1 << ptidxbits) - 1);
439         }
440 
441         /* check that physical address of PTE is legal */
442         hwaddr pte_addr;
443 
444         if (two_stage && first_stage) {
445             int vbase_prot;
446             hwaddr vbase;
447 
448             /* Do the second stage translation on the base PTE address. */
449             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
450                                                  base, MMU_DATA_LOAD,
451                                                  mmu_idx, false, true);
452 
453             if (vbase_ret != TRANSLATE_SUCCESS) {
454                 return vbase_ret;
455             }
456 
457             pte_addr = vbase + idx * ptesize;
458         } else {
459             pte_addr = base + idx * ptesize;
460         }
461 
462         if (riscv_feature(env, RISCV_FEATURE_PMP) &&
463             !pmp_hart_has_privs(env, pte_addr, sizeof(target_ulong),
464             1 << MMU_DATA_LOAD, PRV_S)) {
465             return TRANSLATE_PMP_FAIL;
466         }
467 
468 #if defined(TARGET_RISCV32)
469         target_ulong pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
470 #elif defined(TARGET_RISCV64)
471         target_ulong pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
472 #endif
473         if (res != MEMTX_OK) {
474             return TRANSLATE_FAIL;
475         }
476 
477         hwaddr ppn = pte >> PTE_PPN_SHIFT;
478 
479         if (!(pte & PTE_V)) {
480             /* Invalid PTE */
481             return TRANSLATE_FAIL;
482         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
483             /* Inner PTE, continue walking */
484             base = ppn << PGSHIFT;
485         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
486             /* Reserved leaf PTE flags: PTE_W */
487             return TRANSLATE_FAIL;
488         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
489             /* Reserved leaf PTE flags: PTE_W + PTE_X */
490             return TRANSLATE_FAIL;
491         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
492                    (!sum || access_type == MMU_INST_FETCH))) {
493             /* User PTE flags when not U mode and mstatus.SUM is not set,
494                or the access type is an instruction fetch */
495             return TRANSLATE_FAIL;
496         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
497             /* Supervisor PTE flags when not S mode */
498             return TRANSLATE_FAIL;
499         } else if (ppn & ((1ULL << ptshift) - 1)) {
500             /* Misaligned PPN */
501             return TRANSLATE_FAIL;
502         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
503                    ((pte & PTE_X) && mxr))) {
504             /* Read access check failed */
505             return TRANSLATE_FAIL;
506         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
507             /* Write access check failed */
508             return TRANSLATE_FAIL;
509         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
510             /* Fetch access check failed */
511             return TRANSLATE_FAIL;
512         } else {
513             /* if necessary, set accessed and dirty bits. */
514             target_ulong updated_pte = pte | PTE_A |
515                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
516 
517             /* Page table updates need to be atomic with MTTCG enabled */
518             if (updated_pte != pte) {
519                 /*
520                  * - if accessed or dirty bits need updating, and the PTE is
521                  *   in RAM, then we do so atomically with a compare and swap.
522                  * - if the PTE is in IO space or ROM, then it can't be updated
523                  *   and we return TRANSLATE_FAIL.
524                  * - if the PTE changed by the time we went to update it, then
525                  *   it is no longer valid and we must re-walk the page table.
526                  */
527                 MemoryRegion *mr;
528                 hwaddr l = sizeof(target_ulong), addr1;
529                 mr = address_space_translate(cs->as, pte_addr,
530                     &addr1, &l, false, MEMTXATTRS_UNSPECIFIED);
531                 if (memory_region_is_ram(mr)) {
532                     target_ulong *pte_pa =
533                         qemu_map_ram_ptr(mr->ram_block, addr1);
534 #if TCG_OVERSIZED_GUEST
535                     /* MTTCG is not enabled on oversized TCG guests so
536                      * page table updates do not need to be atomic */
537                     *pte_pa = pte = updated_pte;
538 #else
539                     target_ulong old_pte =
540                         atomic_cmpxchg(pte_pa, pte, updated_pte);
541                     if (old_pte != pte) {
542                         goto restart;
543                     } else {
544                         pte = updated_pte;
545                     }
546 #endif
547                 } else {
548                     /* misconfigured PTE in ROM (AD bits are not preset) or
549                      * PTE is in IO space and can't be updated atomically */
550                     return TRANSLATE_FAIL;
551                 }
552             }
553 
554             /* for superpage mappings, make a fake leaf PTE for the TLB's
555                benefit. */
556             target_ulong vpn = addr >> PGSHIFT;
557             *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) |
558                         (addr & ~TARGET_PAGE_MASK);
559 
560             /* set permissions on the TLB entry */
561             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
562                 *prot |= PAGE_READ;
563             }
564             if ((pte & PTE_X)) {
565                 *prot |= PAGE_EXEC;
566             }
567             /* add write permission on stores or if the page is already dirty,
568                so that we TLB miss on later writes to update the dirty bit */
569             if ((pte & PTE_W) &&
570                     (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
571                 *prot |= PAGE_WRITE;
572             }
573             return TRANSLATE_SUCCESS;
574         }
575     }
576     return TRANSLATE_FAIL;
577 }
578 
579 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
580                                 MMUAccessType access_type, bool pmp_violation,
581                                 bool first_stage)
582 {
583     CPUState *cs = env_cpu(env);
584     int page_fault_exceptions;
585     if (first_stage) {
586         page_fault_exceptions =
587             get_field(env->satp, SATP_MODE) != VM_1_10_MBARE &&
588             !pmp_violation;
589     } else {
590         page_fault_exceptions =
591             get_field(env->hgatp, HGATP_MODE) != VM_1_10_MBARE &&
592             !pmp_violation;
593     }
594     switch (access_type) {
595     case MMU_INST_FETCH:
596         if (riscv_cpu_virt_enabled(env) && !first_stage) {
597             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
598         } else {
599             cs->exception_index = page_fault_exceptions ?
600                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
601         }
602         break;
603     case MMU_DATA_LOAD:
604         if ((riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(env)) &&
605             !first_stage) {
606             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
607         } else {
608             cs->exception_index = page_fault_exceptions ?
609                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
610         }
611         break;
612     case MMU_DATA_STORE:
613         if ((riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(env)) &&
614             !first_stage) {
615             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
616         } else {
617             cs->exception_index = page_fault_exceptions ?
618                 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
619         }
620         break;
621     default:
622         g_assert_not_reached();
623     }
624     env->badaddr = address;
625 }
626 
627 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
628 {
629     RISCVCPU *cpu = RISCV_CPU(cs);
630     CPURISCVState *env = &cpu->env;
631     hwaddr phys_addr;
632     int prot;
633     int mmu_idx = cpu_mmu_index(&cpu->env, false);
634 
635     if (get_physical_address(env, &phys_addr, &prot, addr, 0, mmu_idx,
636                              true, riscv_cpu_virt_enabled(env))) {
637         return -1;
638     }
639 
640     if (riscv_cpu_virt_enabled(env)) {
641         if (get_physical_address(env, &phys_addr, &prot, phys_addr,
642                                  0, mmu_idx, false, true)) {
643             return -1;
644         }
645     }
646 
647     return phys_addr & TARGET_PAGE_MASK;
648 }
649 
650 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
651                                      vaddr addr, unsigned size,
652                                      MMUAccessType access_type,
653                                      int mmu_idx, MemTxAttrs attrs,
654                                      MemTxResult response, uintptr_t retaddr)
655 {
656     RISCVCPU *cpu = RISCV_CPU(cs);
657     CPURISCVState *env = &cpu->env;
658 
659     if (access_type == MMU_DATA_STORE) {
660         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
661     } else {
662         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
663     }
664 
665     env->badaddr = addr;
666     riscv_raise_exception(&cpu->env, cs->exception_index, retaddr);
667 }
668 
669 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
670                                    MMUAccessType access_type, int mmu_idx,
671                                    uintptr_t retaddr)
672 {
673     RISCVCPU *cpu = RISCV_CPU(cs);
674     CPURISCVState *env = &cpu->env;
675     switch (access_type) {
676     case MMU_INST_FETCH:
677         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
678         break;
679     case MMU_DATA_LOAD:
680         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
681         break;
682     case MMU_DATA_STORE:
683         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
684         break;
685     default:
686         g_assert_not_reached();
687     }
688     env->badaddr = addr;
689     riscv_raise_exception(env, cs->exception_index, retaddr);
690 }
691 #endif
692 
693 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
694                         MMUAccessType access_type, int mmu_idx,
695                         bool probe, uintptr_t retaddr)
696 {
697     RISCVCPU *cpu = RISCV_CPU(cs);
698     CPURISCVState *env = &cpu->env;
699 #ifndef CONFIG_USER_ONLY
700     vaddr im_address;
701     hwaddr pa = 0;
702     int prot, prot2;
703     bool pmp_violation = false;
704     bool first_stage_error = true;
705     int ret = TRANSLATE_FAIL;
706     int mode = mmu_idx;
707     target_ulong tlb_size = 0;
708 
709     env->guest_phys_fault_addr = 0;
710 
711     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
712                   __func__, address, access_type, mmu_idx);
713 
714     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
715         if (get_field(env->mstatus, MSTATUS_MPRV)) {
716             mode = get_field(env->mstatus, MSTATUS_MPP);
717         }
718     }
719 
720     if (riscv_has_ext(env, RVH) && env->priv == PRV_M &&
721         access_type != MMU_INST_FETCH &&
722         get_field(env->mstatus, MSTATUS_MPRV) &&
723         MSTATUS_MPV_ISSET(env)) {
724         riscv_cpu_set_two_stage_lookup(env, true);
725     }
726 
727     if (riscv_cpu_virt_enabled(env) ||
728         (riscv_cpu_two_stage_lookup(env) && access_type != MMU_INST_FETCH)) {
729         /* Two stage lookup */
730         ret = get_physical_address(env, &pa, &prot, address, access_type,
731                                    mmu_idx, true, true);
732 
733         qemu_log_mask(CPU_LOG_MMU,
734                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
735                       TARGET_FMT_plx " prot %d\n",
736                       __func__, address, ret, pa, prot);
737 
738         if (ret != TRANSLATE_FAIL) {
739             /* Second stage lookup */
740             im_address = pa;
741 
742             ret = get_physical_address(env, &pa, &prot2, im_address,
743                                        access_type, mmu_idx, false, true);
744 
745             qemu_log_mask(CPU_LOG_MMU,
746                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
747                     TARGET_FMT_plx " prot %d\n",
748                     __func__, im_address, ret, pa, prot2);
749 
750             prot &= prot2;
751 
752             if (riscv_feature(env, RISCV_FEATURE_PMP) &&
753                 (ret == TRANSLATE_SUCCESS) &&
754                 !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
755                 ret = TRANSLATE_PMP_FAIL;
756             }
757 
758             if (ret != TRANSLATE_SUCCESS) {
759                 /*
760                  * Guest physical address translation failed, this is a HS
761                  * level exception
762                  */
763                 first_stage_error = false;
764                 env->guest_phys_fault_addr = (im_address |
765                                               (address &
766                                                (TARGET_PAGE_SIZE - 1))) >> 2;
767             }
768         }
769     } else {
770         /* Single stage lookup */
771         ret = get_physical_address(env, &pa, &prot, address, access_type,
772                                    mmu_idx, true, false);
773 
774         qemu_log_mask(CPU_LOG_MMU,
775                       "%s address=%" VADDR_PRIx " ret %d physical "
776                       TARGET_FMT_plx " prot %d\n",
777                       __func__, address, ret, pa, prot);
778     }
779 
780     /* We did the two stage lookup based on MPRV, unset the lookup */
781     if (riscv_has_ext(env, RVH) && env->priv == PRV_M &&
782         access_type != MMU_INST_FETCH &&
783         get_field(env->mstatus, MSTATUS_MPRV) &&
784         MSTATUS_MPV_ISSET(env)) {
785         riscv_cpu_set_two_stage_lookup(env, false);
786     }
787 
788     if (riscv_feature(env, RISCV_FEATURE_PMP) &&
789         (ret == TRANSLATE_SUCCESS) &&
790         !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
791         ret = TRANSLATE_PMP_FAIL;
792     }
793     if (ret == TRANSLATE_PMP_FAIL) {
794         pmp_violation = true;
795     }
796 
797     if (ret == TRANSLATE_SUCCESS) {
798         if (pmp_is_range_in_tlb(env, pa & TARGET_PAGE_MASK, &tlb_size)) {
799             tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
800                          prot, mmu_idx, tlb_size);
801         } else {
802             tlb_set_page(cs, address & TARGET_PAGE_MASK, pa & TARGET_PAGE_MASK,
803                          prot, mmu_idx, TARGET_PAGE_SIZE);
804         }
805         return true;
806     } else if (probe) {
807         return false;
808     } else {
809         raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error);
810         riscv_raise_exception(env, cs->exception_index, retaddr);
811     }
812 
813     return true;
814 
815 #else
816     switch (access_type) {
817     case MMU_INST_FETCH:
818         cs->exception_index = RISCV_EXCP_INST_PAGE_FAULT;
819         break;
820     case MMU_DATA_LOAD:
821         cs->exception_index = RISCV_EXCP_LOAD_PAGE_FAULT;
822         break;
823     case MMU_DATA_STORE:
824         cs->exception_index = RISCV_EXCP_STORE_PAGE_FAULT;
825         break;
826     default:
827         g_assert_not_reached();
828     }
829     env->badaddr = address;
830     cpu_loop_exit_restore(cs, retaddr);
831 #endif
832 }
833 
834 /*
835  * Handle Traps
836  *
837  * Adapted from Spike's processor_t::take_trap.
838  *
839  */
840 void riscv_cpu_do_interrupt(CPUState *cs)
841 {
842 #if !defined(CONFIG_USER_ONLY)
843 
844     RISCVCPU *cpu = RISCV_CPU(cs);
845     CPURISCVState *env = &cpu->env;
846     bool force_hs_execp = riscv_cpu_force_hs_excep_enabled(env);
847     target_ulong s;
848 
849     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
850      * so we mask off the MSB and separate into trap type and cause.
851      */
852     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
853     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
854     target_ulong deleg = async ? env->mideleg : env->medeleg;
855     target_ulong tval = 0;
856     target_ulong htval = 0;
857     target_ulong mtval2 = 0;
858 
859     if (!async) {
860         /* set tval to badaddr for traps with address information */
861         switch (cause) {
862         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
863         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
864         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
865             force_hs_execp = true;
866             /* fallthrough */
867         case RISCV_EXCP_INST_ADDR_MIS:
868         case RISCV_EXCP_INST_ACCESS_FAULT:
869         case RISCV_EXCP_LOAD_ADDR_MIS:
870         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
871         case RISCV_EXCP_LOAD_ACCESS_FAULT:
872         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
873         case RISCV_EXCP_INST_PAGE_FAULT:
874         case RISCV_EXCP_LOAD_PAGE_FAULT:
875         case RISCV_EXCP_STORE_PAGE_FAULT:
876             tval = env->badaddr;
877             break;
878         default:
879             break;
880         }
881         /* ecall is dispatched as one cause so translate based on mode */
882         if (cause == RISCV_EXCP_U_ECALL) {
883             assert(env->priv <= 3);
884 
885             if (env->priv == PRV_M) {
886                 cause = RISCV_EXCP_M_ECALL;
887             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
888                 cause = RISCV_EXCP_VS_ECALL;
889             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
890                 cause = RISCV_EXCP_S_ECALL;
891             } else if (env->priv == PRV_U) {
892                 cause = RISCV_EXCP_U_ECALL;
893             }
894         }
895     }
896 
897     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
898         riscv_cpu_get_trap_name(cause, async));
899 
900     if (env->priv <= PRV_S &&
901             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
902         /* handle the trap in S-mode */
903         if (riscv_has_ext(env, RVH)) {
904             target_ulong hdeleg = async ? env->hideleg : env->hedeleg;
905 
906             if ((riscv_cpu_virt_enabled(env) ||
907                  riscv_cpu_two_stage_lookup(env)) && tval) {
908                 /*
909                  * If we are writing a guest virtual address to stval, set
910                  * this to 1. If we are trapping to VS we will set this to 0
911                  * later.
912                  */
913                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 1);
914             } else {
915                 /* For other HS-mode traps, we set this to 0. */
916                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0);
917             }
918 
919             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1) &&
920                 !force_hs_execp) {
921                 /* Trap to VS mode */
922                 /*
923                  * See if we need to adjust cause. Yes if its VS mode interrupt
924                  * no if hypervisor has delegated one of hs mode's interrupt
925                  */
926                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
927                     cause == IRQ_VS_EXT) {
928                     cause = cause - 1;
929                 }
930                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0);
931             } else if (riscv_cpu_virt_enabled(env)) {
932                 /* Trap into HS mode, from virt */
933                 riscv_cpu_swap_hypervisor_regs(env);
934                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
935                                          get_field(env->mstatus, SSTATUS_SPP));
936                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
937                                          riscv_cpu_virt_enabled(env));
938 
939                 htval = env->guest_phys_fault_addr;
940 
941                 riscv_cpu_set_virt_enabled(env, 0);
942                 riscv_cpu_set_force_hs_excep(env, 0);
943             } else {
944                 /* Trap into HS mode */
945                 if (!riscv_cpu_two_stage_lookup(env)) {
946                     env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
947                                              riscv_cpu_virt_enabled(env));
948                 }
949                 riscv_cpu_set_two_stage_lookup(env, false);
950                 htval = env->guest_phys_fault_addr;
951             }
952         }
953 
954         s = env->mstatus;
955         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
956         s = set_field(s, MSTATUS_SPP, env->priv);
957         s = set_field(s, MSTATUS_SIE, 0);
958         env->mstatus = s;
959         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
960         env->sepc = env->pc;
961         env->sbadaddr = tval;
962         env->htval = htval;
963         env->pc = (env->stvec >> 2 << 2) +
964             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
965         riscv_cpu_set_mode(env, PRV_S);
966     } else {
967         /* handle the trap in M-mode */
968         if (riscv_has_ext(env, RVH)) {
969             if (riscv_cpu_virt_enabled(env)) {
970                 riscv_cpu_swap_hypervisor_regs(env);
971             }
972 #ifdef TARGET_RISCV32
973             env->mstatush = set_field(env->mstatush, MSTATUS_MPV,
974                                        riscv_cpu_virt_enabled(env));
975             if (riscv_cpu_virt_enabled(env) && tval) {
976                 env->mstatush = set_field(env->mstatush, MSTATUS_GVA, 1);
977             }
978 #else
979             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
980                                       riscv_cpu_virt_enabled(env));
981             if (riscv_cpu_virt_enabled(env) && tval) {
982                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
983             }
984 #endif
985 
986             mtval2 = env->guest_phys_fault_addr;
987 
988             /* Trapping to M mode, virt is disabled */
989             riscv_cpu_set_virt_enabled(env, 0);
990             riscv_cpu_set_force_hs_excep(env, 0);
991         }
992 
993         s = env->mstatus;
994         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
995         s = set_field(s, MSTATUS_MPP, env->priv);
996         s = set_field(s, MSTATUS_MIE, 0);
997         env->mstatus = s;
998         env->mcause = cause | ~(((target_ulong)-1) >> async);
999         env->mepc = env->pc;
1000         env->mbadaddr = tval;
1001         env->mtval2 = mtval2;
1002         env->pc = (env->mtvec >> 2 << 2) +
1003             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
1004         riscv_cpu_set_mode(env, PRV_M);
1005     }
1006 
1007     /* NOTE: it is not necessary to yield load reservations here. It is only
1008      * necessary for an SC from "another hart" to cause a load reservation
1009      * to be yielded. Refer to the memory consistency model section of the
1010      * RISC-V ISA Specification.
1011      */
1012 
1013 #endif
1014     cs->exception_index = EXCP_NONE; /* mark handled to qemu */
1015 }
1016