xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision 9ef82119)
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 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts)
224 {
225     CPURISCVState *env = &cpu->env;
226     if (env->miclaim & interrupts) {
227         return -1;
228     } else {
229         env->miclaim |= interrupts;
230         return 0;
231     }
232 }
233 
234 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value)
235 {
236     CPURISCVState *env = &cpu->env;
237     CPUState *cs = CPU(cpu);
238     uint32_t old = env->mip;
239     bool locked = false;
240 
241     if (!qemu_mutex_iothread_locked()) {
242         locked = true;
243         qemu_mutex_lock_iothread();
244     }
245 
246     env->mip = (env->mip & ~mask) | (value & mask);
247 
248     if (env->mip) {
249         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
250     } else {
251         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
252     }
253 
254     if (locked) {
255         qemu_mutex_unlock_iothread();
256     }
257 
258     return old;
259 }
260 
261 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void))
262 {
263     env->rdtime_fn = fn;
264 }
265 
266 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv)
267 {
268     if (newpriv > PRV_M) {
269         g_assert_not_reached();
270     }
271     if (newpriv == PRV_H) {
272         newpriv = PRV_U;
273     }
274     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
275     env->priv = newpriv;
276 
277     /*
278      * Clear the load reservation - otherwise a reservation placed in one
279      * context/process can be used by another, resulting in an SC succeeding
280      * incorrectly. Version 2.2 of the ISA specification explicitly requires
281      * this behaviour, while later revisions say that the kernel "should" use
282      * an SC instruction to force the yielding of a load reservation on a
283      * preemptive context switch. As a result, do both.
284      */
285     env->load_res = -1;
286 }
287 
288 /* get_physical_address - get the physical address for this virtual address
289  *
290  * Do a page table walk to obtain the physical address corresponding to a
291  * virtual address. Returns 0 if the translation was successful
292  *
293  * Adapted from Spike's mmu_t::translate and mmu_t::walk
294  *
295  * @env: CPURISCVState
296  * @physical: This will be set to the calculated physical address
297  * @prot: The returned protection attributes
298  * @addr: The virtual address to be translated
299  * @access_type: The type of MMU access
300  * @mmu_idx: Indicates current privilege level
301  * @first_stage: Are we in first stage translation?
302  *               Second stage is used for hypervisor guest translation
303  * @two_stage: Are we going to perform two stage translation
304  */
305 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
306                                 int *prot, target_ulong addr,
307                                 int access_type, int mmu_idx,
308                                 bool first_stage, bool two_stage)
309 {
310     /* NOTE: the env->pc value visible here will not be
311      * correct, but the value visible to the exception handler
312      * (riscv_cpu_do_interrupt) is correct */
313     MemTxResult res;
314     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
315     int mode = mmu_idx;
316     bool use_background = false;
317 
318     /*
319      * Check if we should use the background registers for the two
320      * stage translation. We don't need to check if we actually need
321      * two stage translation as that happened before this function
322      * was called. Background registers will be used if the guest has
323      * forced a two stage translation to be on (in HS or M mode).
324      */
325     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
326         if (get_field(env->mstatus, MSTATUS_MPRV)) {
327             mode = get_field(env->mstatus, MSTATUS_MPP);
328 
329             if (riscv_has_ext(env, RVH) &&
330                 MSTATUS_MPV_ISSET(env)) {
331                 use_background = true;
332             }
333         }
334     }
335 
336     if (mode == PRV_S && access_type != MMU_INST_FETCH &&
337         riscv_has_ext(env, RVH) && !riscv_cpu_virt_enabled(env)) {
338         if (get_field(env->hstatus, HSTATUS_SPRV)) {
339             mode = get_field(env->mstatus, SSTATUS_SPP);
340             use_background = true;
341         }
342     }
343 
344     if (first_stage == false) {
345         /* We are in stage 2 translation, this is similar to stage 1. */
346         /* Stage 2 is always taken as U-mode */
347         mode = PRV_U;
348     }
349 
350     if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) {
351         *physical = addr;
352         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
353         return TRANSLATE_SUCCESS;
354     }
355 
356     *prot = 0;
357 
358     hwaddr base;
359     int levels, ptidxbits, ptesize, vm, sum, mxr, widened;
360 
361     if (first_stage == true) {
362         mxr = get_field(env->mstatus, MSTATUS_MXR);
363     } else {
364         mxr = get_field(env->vsstatus, MSTATUS_MXR);
365     }
366 
367     if (first_stage == true) {
368         if (use_background) {
369             base = (hwaddr)get_field(env->vsatp, SATP_PPN) << PGSHIFT;
370             vm = get_field(env->vsatp, SATP_MODE);
371         } else {
372             base = (hwaddr)get_field(env->satp, SATP_PPN) << PGSHIFT;
373             vm = get_field(env->satp, SATP_MODE);
374         }
375         widened = 0;
376     } else {
377         base = (hwaddr)get_field(env->hgatp, HGATP_PPN) << PGSHIFT;
378         vm = get_field(env->hgatp, HGATP_MODE);
379         widened = 2;
380     }
381     sum = get_field(env->mstatus, MSTATUS_SUM);
382     switch (vm) {
383     case VM_1_10_SV32:
384       levels = 2; ptidxbits = 10; ptesize = 4; break;
385     case VM_1_10_SV39:
386       levels = 3; ptidxbits = 9; ptesize = 8; break;
387     case VM_1_10_SV48:
388       levels = 4; ptidxbits = 9; ptesize = 8; break;
389     case VM_1_10_SV57:
390       levels = 5; ptidxbits = 9; ptesize = 8; break;
391     case VM_1_10_MBARE:
392         *physical = addr;
393         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
394         return TRANSLATE_SUCCESS;
395     default:
396       g_assert_not_reached();
397     }
398 
399     CPUState *cs = env_cpu(env);
400     int va_bits = PGSHIFT + levels * ptidxbits + widened;
401     target_ulong mask, masked_msbs;
402 
403     if (TARGET_LONG_BITS > (va_bits - 1)) {
404         mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1;
405     } else {
406         mask = 0;
407     }
408     masked_msbs = (addr >> (va_bits - 1)) & mask;
409 
410     if (masked_msbs != 0 && masked_msbs != mask) {
411         return TRANSLATE_FAIL;
412     }
413 
414     int ptshift = (levels - 1) * ptidxbits;
415     int i;
416 
417 #if !TCG_OVERSIZED_GUEST
418 restart:
419 #endif
420     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
421         target_ulong idx;
422         if (i == 0) {
423             idx = (addr >> (PGSHIFT + ptshift)) &
424                            ((1 << (ptidxbits + widened)) - 1);
425         } else {
426             idx = (addr >> (PGSHIFT + ptshift)) &
427                            ((1 << ptidxbits) - 1);
428         }
429 
430         /* check that physical address of PTE is legal */
431         hwaddr pte_addr;
432 
433         if (two_stage && first_stage) {
434             int vbase_prot;
435             hwaddr vbase;
436 
437             /* Do the second stage translation on the base PTE address. */
438             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
439                                                  base, MMU_DATA_LOAD,
440                                                  mmu_idx, false, true);
441 
442             if (vbase_ret != TRANSLATE_SUCCESS) {
443                 return vbase_ret;
444             }
445 
446             pte_addr = vbase + idx * ptesize;
447         } else {
448             pte_addr = base + idx * ptesize;
449         }
450 
451         if (riscv_feature(env, RISCV_FEATURE_PMP) &&
452             !pmp_hart_has_privs(env, pte_addr, sizeof(target_ulong),
453             1 << MMU_DATA_LOAD, PRV_S)) {
454             return TRANSLATE_PMP_FAIL;
455         }
456 
457 #if defined(TARGET_RISCV32)
458         target_ulong pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
459 #elif defined(TARGET_RISCV64)
460         target_ulong pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
461 #endif
462         if (res != MEMTX_OK) {
463             return TRANSLATE_FAIL;
464         }
465 
466         hwaddr ppn = pte >> PTE_PPN_SHIFT;
467 
468         if (!(pte & PTE_V)) {
469             /* Invalid PTE */
470             return TRANSLATE_FAIL;
471         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
472             /* Inner PTE, continue walking */
473             base = ppn << PGSHIFT;
474         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
475             /* Reserved leaf PTE flags: PTE_W */
476             return TRANSLATE_FAIL;
477         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
478             /* Reserved leaf PTE flags: PTE_W + PTE_X */
479             return TRANSLATE_FAIL;
480         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
481                    (!sum || access_type == MMU_INST_FETCH))) {
482             /* User PTE flags when not U mode and mstatus.SUM is not set,
483                or the access type is an instruction fetch */
484             return TRANSLATE_FAIL;
485         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
486             /* Supervisor PTE flags when not S mode */
487             return TRANSLATE_FAIL;
488         } else if (ppn & ((1ULL << ptshift) - 1)) {
489             /* Misaligned PPN */
490             return TRANSLATE_FAIL;
491         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
492                    ((pte & PTE_X) && mxr))) {
493             /* Read access check failed */
494             return TRANSLATE_FAIL;
495         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
496             /* Write access check failed */
497             return TRANSLATE_FAIL;
498         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
499             /* Fetch access check failed */
500             return TRANSLATE_FAIL;
501         } else {
502             /* if necessary, set accessed and dirty bits. */
503             target_ulong updated_pte = pte | PTE_A |
504                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
505 
506             /* Page table updates need to be atomic with MTTCG enabled */
507             if (updated_pte != pte) {
508                 /*
509                  * - if accessed or dirty bits need updating, and the PTE is
510                  *   in RAM, then we do so atomically with a compare and swap.
511                  * - if the PTE is in IO space or ROM, then it can't be updated
512                  *   and we return TRANSLATE_FAIL.
513                  * - if the PTE changed by the time we went to update it, then
514                  *   it is no longer valid and we must re-walk the page table.
515                  */
516                 MemoryRegion *mr;
517                 hwaddr l = sizeof(target_ulong), addr1;
518                 mr = address_space_translate(cs->as, pte_addr,
519                     &addr1, &l, false, MEMTXATTRS_UNSPECIFIED);
520                 if (memory_region_is_ram(mr)) {
521                     target_ulong *pte_pa =
522                         qemu_map_ram_ptr(mr->ram_block, addr1);
523 #if TCG_OVERSIZED_GUEST
524                     /* MTTCG is not enabled on oversized TCG guests so
525                      * page table updates do not need to be atomic */
526                     *pte_pa = pte = updated_pte;
527 #else
528                     target_ulong old_pte =
529                         atomic_cmpxchg(pte_pa, pte, updated_pte);
530                     if (old_pte != pte) {
531                         goto restart;
532                     } else {
533                         pte = updated_pte;
534                     }
535 #endif
536                 } else {
537                     /* misconfigured PTE in ROM (AD bits are not preset) or
538                      * PTE is in IO space and can't be updated atomically */
539                     return TRANSLATE_FAIL;
540                 }
541             }
542 
543             /* for superpage mappings, make a fake leaf PTE for the TLB's
544                benefit. */
545             target_ulong vpn = addr >> PGSHIFT;
546             *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) |
547                         (addr & ~TARGET_PAGE_MASK);
548 
549             /* set permissions on the TLB entry */
550             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
551                 *prot |= PAGE_READ;
552             }
553             if ((pte & PTE_X)) {
554                 *prot |= PAGE_EXEC;
555             }
556             /* add write permission on stores or if the page is already dirty,
557                so that we TLB miss on later writes to update the dirty bit */
558             if ((pte & PTE_W) &&
559                     (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
560                 *prot |= PAGE_WRITE;
561             }
562             return TRANSLATE_SUCCESS;
563         }
564     }
565     return TRANSLATE_FAIL;
566 }
567 
568 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
569                                 MMUAccessType access_type, bool pmp_violation,
570                                 bool first_stage)
571 {
572     CPUState *cs = env_cpu(env);
573     int page_fault_exceptions;
574     if (first_stage) {
575         page_fault_exceptions =
576             get_field(env->satp, SATP_MODE) != VM_1_10_MBARE &&
577             !pmp_violation;
578     } else {
579         page_fault_exceptions =
580             get_field(env->hgatp, HGATP_MODE) != VM_1_10_MBARE &&
581             !pmp_violation;
582     }
583     switch (access_type) {
584     case MMU_INST_FETCH:
585         if (riscv_cpu_virt_enabled(env) && !first_stage) {
586             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
587         } else {
588             cs->exception_index = page_fault_exceptions ?
589                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
590         }
591         break;
592     case MMU_DATA_LOAD:
593         if (riscv_cpu_virt_enabled(env) && !first_stage) {
594             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
595         } else {
596             cs->exception_index = page_fault_exceptions ?
597                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
598         }
599         break;
600     case MMU_DATA_STORE:
601         if (riscv_cpu_virt_enabled(env) && !first_stage) {
602             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
603         } else {
604             cs->exception_index = page_fault_exceptions ?
605                 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
606         }
607         break;
608     default:
609         g_assert_not_reached();
610     }
611     env->badaddr = address;
612 }
613 
614 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
615 {
616     RISCVCPU *cpu = RISCV_CPU(cs);
617     CPURISCVState *env = &cpu->env;
618     hwaddr phys_addr;
619     int prot;
620     int mmu_idx = cpu_mmu_index(&cpu->env, false);
621 
622     if (get_physical_address(env, &phys_addr, &prot, addr, 0, mmu_idx,
623                              true, riscv_cpu_virt_enabled(env))) {
624         return -1;
625     }
626 
627     if (riscv_cpu_virt_enabled(env)) {
628         if (get_physical_address(env, &phys_addr, &prot, phys_addr,
629                                  0, mmu_idx, false, true)) {
630             return -1;
631         }
632     }
633 
634     return phys_addr & TARGET_PAGE_MASK;
635 }
636 
637 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
638                                      vaddr addr, unsigned size,
639                                      MMUAccessType access_type,
640                                      int mmu_idx, MemTxAttrs attrs,
641                                      MemTxResult response, uintptr_t retaddr)
642 {
643     RISCVCPU *cpu = RISCV_CPU(cs);
644     CPURISCVState *env = &cpu->env;
645 
646     if (access_type == MMU_DATA_STORE) {
647         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
648     } else {
649         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
650     }
651 
652     env->badaddr = addr;
653     riscv_raise_exception(&cpu->env, cs->exception_index, retaddr);
654 }
655 
656 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
657                                    MMUAccessType access_type, int mmu_idx,
658                                    uintptr_t retaddr)
659 {
660     RISCVCPU *cpu = RISCV_CPU(cs);
661     CPURISCVState *env = &cpu->env;
662     switch (access_type) {
663     case MMU_INST_FETCH:
664         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
665         break;
666     case MMU_DATA_LOAD:
667         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
668         break;
669     case MMU_DATA_STORE:
670         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
671         break;
672     default:
673         g_assert_not_reached();
674     }
675     env->badaddr = addr;
676     riscv_raise_exception(env, cs->exception_index, retaddr);
677 }
678 #endif
679 
680 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
681                         MMUAccessType access_type, int mmu_idx,
682                         bool probe, uintptr_t retaddr)
683 {
684     RISCVCPU *cpu = RISCV_CPU(cs);
685     CPURISCVState *env = &cpu->env;
686 #ifndef CONFIG_USER_ONLY
687     vaddr im_address;
688     hwaddr pa = 0;
689     int prot, prot2;
690     bool pmp_violation = false;
691     bool m_mode_two_stage = false;
692     bool hs_mode_two_stage = false;
693     bool first_stage_error = true;
694     int ret = TRANSLATE_FAIL;
695     int mode = mmu_idx;
696 
697     env->guest_phys_fault_addr = 0;
698 
699     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
700                   __func__, address, access_type, mmu_idx);
701 
702     /*
703      * Determine if we are in M mode and MPRV is set or in HS mode and SPRV is
704      * set and we want to access a virtulisation address.
705      */
706     if (riscv_has_ext(env, RVH)) {
707         m_mode_two_stage = env->priv == PRV_M &&
708                            access_type != MMU_INST_FETCH &&
709                            get_field(env->mstatus, MSTATUS_MPRV) &&
710                            MSTATUS_MPV_ISSET(env);
711 
712         hs_mode_two_stage = env->priv == PRV_S &&
713                             !riscv_cpu_virt_enabled(env) &&
714                             access_type != MMU_INST_FETCH &&
715                             get_field(env->hstatus, HSTATUS_SPRV) &&
716                             get_field(env->hstatus, HSTATUS_SPV);
717     }
718 
719     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
720         if (get_field(env->mstatus, MSTATUS_MPRV)) {
721             mode = get_field(env->mstatus, MSTATUS_MPP);
722         }
723     }
724 
725     if (riscv_cpu_virt_enabled(env) || m_mode_two_stage || hs_mode_two_stage) {
726         /* Two stage lookup */
727         ret = get_physical_address(env, &pa, &prot, address, access_type,
728                                    mmu_idx, true, true);
729 
730         qemu_log_mask(CPU_LOG_MMU,
731                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
732                       TARGET_FMT_plx " prot %d\n",
733                       __func__, address, ret, pa, prot);
734 
735         if (ret != TRANSLATE_FAIL) {
736             /* Second stage lookup */
737             im_address = pa;
738 
739             ret = get_physical_address(env, &pa, &prot2, im_address,
740                                        access_type, mmu_idx, false, true);
741 
742             qemu_log_mask(CPU_LOG_MMU,
743                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
744                     TARGET_FMT_plx " prot %d\n",
745                     __func__, im_address, ret, pa, prot2);
746 
747             prot &= prot2;
748 
749             if (riscv_feature(env, RISCV_FEATURE_PMP) &&
750                 (ret == TRANSLATE_SUCCESS) &&
751                 !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
752                 ret = TRANSLATE_PMP_FAIL;
753             }
754 
755             if (ret != TRANSLATE_SUCCESS) {
756                 /*
757                  * Guest physical address translation failed, this is a HS
758                  * level exception
759                  */
760                 first_stage_error = false;
761                 env->guest_phys_fault_addr = (im_address |
762                                               (address &
763                                                (TARGET_PAGE_SIZE - 1))) >> 2;
764             }
765         }
766     } else {
767         /* Single stage lookup */
768         ret = get_physical_address(env, &pa, &prot, address, access_type,
769                                    mmu_idx, true, false);
770 
771         qemu_log_mask(CPU_LOG_MMU,
772                       "%s address=%" VADDR_PRIx " ret %d physical "
773                       TARGET_FMT_plx " prot %d\n",
774                       __func__, address, ret, pa, prot);
775     }
776 
777     if (riscv_feature(env, RISCV_FEATURE_PMP) &&
778         (ret == TRANSLATE_SUCCESS) &&
779         !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
780         ret = TRANSLATE_PMP_FAIL;
781     }
782     if (ret == TRANSLATE_PMP_FAIL) {
783         pmp_violation = true;
784     }
785 
786     if (ret == TRANSLATE_SUCCESS) {
787         tlb_set_page(cs, address & TARGET_PAGE_MASK, pa & TARGET_PAGE_MASK,
788                      prot, mmu_idx, TARGET_PAGE_SIZE);
789         return true;
790     } else if (probe) {
791         return false;
792     } else {
793         raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error);
794         riscv_raise_exception(env, cs->exception_index, retaddr);
795     }
796 
797     return true;
798 
799 #else
800     switch (access_type) {
801     case MMU_INST_FETCH:
802         cs->exception_index = RISCV_EXCP_INST_PAGE_FAULT;
803         break;
804     case MMU_DATA_LOAD:
805         cs->exception_index = RISCV_EXCP_LOAD_PAGE_FAULT;
806         break;
807     case MMU_DATA_STORE:
808         cs->exception_index = RISCV_EXCP_STORE_PAGE_FAULT;
809         break;
810     default:
811         g_assert_not_reached();
812     }
813     env->badaddr = address;
814     cpu_loop_exit_restore(cs, retaddr);
815 #endif
816 }
817 
818 /*
819  * Handle Traps
820  *
821  * Adapted from Spike's processor_t::take_trap.
822  *
823  */
824 void riscv_cpu_do_interrupt(CPUState *cs)
825 {
826 #if !defined(CONFIG_USER_ONLY)
827 
828     RISCVCPU *cpu = RISCV_CPU(cs);
829     CPURISCVState *env = &cpu->env;
830     bool force_hs_execp = riscv_cpu_force_hs_excep_enabled(env);
831     target_ulong s;
832 
833     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
834      * so we mask off the MSB and separate into trap type and cause.
835      */
836     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
837     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
838     target_ulong deleg = async ? env->mideleg : env->medeleg;
839     target_ulong tval = 0;
840     target_ulong htval = 0;
841     target_ulong mtval2 = 0;
842 
843     if (!async) {
844         /* set tval to badaddr for traps with address information */
845         switch (cause) {
846         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
847         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
848         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
849             force_hs_execp = true;
850             /* fallthrough */
851         case RISCV_EXCP_INST_ADDR_MIS:
852         case RISCV_EXCP_INST_ACCESS_FAULT:
853         case RISCV_EXCP_LOAD_ADDR_MIS:
854         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
855         case RISCV_EXCP_LOAD_ACCESS_FAULT:
856         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
857         case RISCV_EXCP_INST_PAGE_FAULT:
858         case RISCV_EXCP_LOAD_PAGE_FAULT:
859         case RISCV_EXCP_STORE_PAGE_FAULT:
860             tval = env->badaddr;
861             break;
862         default:
863             break;
864         }
865         /* ecall is dispatched as one cause so translate based on mode */
866         if (cause == RISCV_EXCP_U_ECALL) {
867             assert(env->priv <= 3);
868 
869             if (env->priv == PRV_M) {
870                 cause = RISCV_EXCP_M_ECALL;
871             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
872                 cause = RISCV_EXCP_VS_ECALL;
873             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
874                 cause = RISCV_EXCP_S_ECALL;
875             } else if (env->priv == PRV_U) {
876                 cause = RISCV_EXCP_U_ECALL;
877             }
878         }
879     }
880 
881     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval, cause < 23 ?
882         (async ? riscv_intr_names : riscv_excp_names)[cause] : "(unknown)");
883 
884     if (env->priv <= PRV_S &&
885             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
886         /* handle the trap in S-mode */
887         if (riscv_has_ext(env, RVH)) {
888             target_ulong hdeleg = async ? env->hideleg : env->hedeleg;
889 
890             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1) &&
891                 !force_hs_execp) {
892                 /*
893                  * See if we need to adjust cause. Yes if its VS mode interrupt
894                  * no if hypervisor has delegated one of hs mode's interrupt
895                  */
896                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
897                     cause == IRQ_VS_EXT)
898                     cause = cause - 1;
899                 /* Trap to VS mode */
900             } else if (riscv_cpu_virt_enabled(env)) {
901                 /* Trap into HS mode, from virt */
902                 riscv_cpu_swap_hypervisor_regs(env);
903                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2V,
904                                          get_field(env->hstatus, HSTATUS_SPV));
905                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2P,
906                                          get_field(env->mstatus, SSTATUS_SPP));
907                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
908                                          riscv_cpu_virt_enabled(env));
909 
910                 htval = env->guest_phys_fault_addr;
911 
912                 riscv_cpu_set_virt_enabled(env, 0);
913                 riscv_cpu_set_force_hs_excep(env, 0);
914             } else {
915                 /* Trap into HS mode */
916                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2V,
917                                          get_field(env->hstatus, HSTATUS_SPV));
918                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2P,
919                                          get_field(env->mstatus, SSTATUS_SPP));
920                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
921                                          riscv_cpu_virt_enabled(env));
922 
923                 htval = env->guest_phys_fault_addr;
924             }
925         }
926 
927         s = env->mstatus;
928         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
929         s = set_field(s, MSTATUS_SPP, env->priv);
930         s = set_field(s, MSTATUS_SIE, 0);
931         env->mstatus = s;
932         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
933         env->sepc = env->pc;
934         env->sbadaddr = tval;
935         env->htval = htval;
936         env->pc = (env->stvec >> 2 << 2) +
937             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
938         riscv_cpu_set_mode(env, PRV_S);
939     } else {
940         /* handle the trap in M-mode */
941         if (riscv_has_ext(env, RVH)) {
942             if (riscv_cpu_virt_enabled(env)) {
943                 riscv_cpu_swap_hypervisor_regs(env);
944             }
945 #ifdef TARGET_RISCV32
946             env->mstatush = set_field(env->mstatush, MSTATUS_MPV,
947                                        riscv_cpu_virt_enabled(env));
948             env->mstatush = set_field(env->mstatush, MSTATUS_MTL,
949                                        riscv_cpu_force_hs_excep_enabled(env));
950 #else
951             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
952                                       riscv_cpu_virt_enabled(env));
953             env->mstatus = set_field(env->mstatus, MSTATUS_MTL,
954                                       riscv_cpu_force_hs_excep_enabled(env));
955 #endif
956 
957             mtval2 = env->guest_phys_fault_addr;
958 
959             /* Trapping to M mode, virt is disabled */
960             riscv_cpu_set_virt_enabled(env, 0);
961             riscv_cpu_set_force_hs_excep(env, 0);
962         }
963 
964         s = env->mstatus;
965         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
966         s = set_field(s, MSTATUS_MPP, env->priv);
967         s = set_field(s, MSTATUS_MIE, 0);
968         env->mstatus = s;
969         env->mcause = cause | ~(((target_ulong)-1) >> async);
970         env->mepc = env->pc;
971         env->mbadaddr = tval;
972         env->mtval2 = mtval2;
973         env->pc = (env->mtvec >> 2 << 2) +
974             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
975         riscv_cpu_set_mode(env, PRV_M);
976     }
977 
978     /* NOTE: it is not necessary to yield load reservations here. It is only
979      * necessary for an SC from "another hart" to cause a load reservation
980      * to be yielded. Refer to the memory consistency model section of the
981      * RISC-V ISA Specification.
982      */
983 
984 #endif
985     cs->exception_index = EXCP_NONE; /* mark handled to qemu */
986 }
987