xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision efe9f9c8)
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             get_physical_address(env, &vbase, &vbase_prot, base, MMU_DATA_LOAD,
439                                  mmu_idx, false, true);
440 
441             pte_addr = vbase + idx * ptesize;
442         } else {
443             pte_addr = base + idx * ptesize;
444         }
445 
446         if (riscv_feature(env, RISCV_FEATURE_PMP) &&
447             !pmp_hart_has_privs(env, pte_addr, sizeof(target_ulong),
448             1 << MMU_DATA_LOAD, PRV_S)) {
449             return TRANSLATE_PMP_FAIL;
450         }
451 
452 #if defined(TARGET_RISCV32)
453         target_ulong pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
454 #elif defined(TARGET_RISCV64)
455         target_ulong pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
456 #endif
457         if (res != MEMTX_OK) {
458             return TRANSLATE_FAIL;
459         }
460 
461         hwaddr ppn = pte >> PTE_PPN_SHIFT;
462 
463         if (!(pte & PTE_V)) {
464             /* Invalid PTE */
465             return TRANSLATE_FAIL;
466         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
467             /* Inner PTE, continue walking */
468             base = ppn << PGSHIFT;
469         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
470             /* Reserved leaf PTE flags: PTE_W */
471             return TRANSLATE_FAIL;
472         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
473             /* Reserved leaf PTE flags: PTE_W + PTE_X */
474             return TRANSLATE_FAIL;
475         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
476                    (!sum || access_type == MMU_INST_FETCH))) {
477             /* User PTE flags when not U mode and mstatus.SUM is not set,
478                or the access type is an instruction fetch */
479             return TRANSLATE_FAIL;
480         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
481             /* Supervisor PTE flags when not S mode */
482             return TRANSLATE_FAIL;
483         } else if (ppn & ((1ULL << ptshift) - 1)) {
484             /* Misaligned PPN */
485             return TRANSLATE_FAIL;
486         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
487                    ((pte & PTE_X) && mxr))) {
488             /* Read access check failed */
489             return TRANSLATE_FAIL;
490         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
491             /* Write access check failed */
492             return TRANSLATE_FAIL;
493         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
494             /* Fetch access check failed */
495             return TRANSLATE_FAIL;
496         } else {
497             /* if necessary, set accessed and dirty bits. */
498             target_ulong updated_pte = pte | PTE_A |
499                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
500 
501             /* Page table updates need to be atomic with MTTCG enabled */
502             if (updated_pte != pte) {
503                 /*
504                  * - if accessed or dirty bits need updating, and the PTE is
505                  *   in RAM, then we do so atomically with a compare and swap.
506                  * - if the PTE is in IO space or ROM, then it can't be updated
507                  *   and we return TRANSLATE_FAIL.
508                  * - if the PTE changed by the time we went to update it, then
509                  *   it is no longer valid and we must re-walk the page table.
510                  */
511                 MemoryRegion *mr;
512                 hwaddr l = sizeof(target_ulong), addr1;
513                 mr = address_space_translate(cs->as, pte_addr,
514                     &addr1, &l, false, MEMTXATTRS_UNSPECIFIED);
515                 if (memory_region_is_ram(mr)) {
516                     target_ulong *pte_pa =
517                         qemu_map_ram_ptr(mr->ram_block, addr1);
518 #if TCG_OVERSIZED_GUEST
519                     /* MTTCG is not enabled on oversized TCG guests so
520                      * page table updates do not need to be atomic */
521                     *pte_pa = pte = updated_pte;
522 #else
523                     target_ulong old_pte =
524                         atomic_cmpxchg(pte_pa, pte, updated_pte);
525                     if (old_pte != pte) {
526                         goto restart;
527                     } else {
528                         pte = updated_pte;
529                     }
530 #endif
531                 } else {
532                     /* misconfigured PTE in ROM (AD bits are not preset) or
533                      * PTE is in IO space and can't be updated atomically */
534                     return TRANSLATE_FAIL;
535                 }
536             }
537 
538             /* for superpage mappings, make a fake leaf PTE for the TLB's
539                benefit. */
540             target_ulong vpn = addr >> PGSHIFT;
541             *physical = (ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT;
542 
543             /* set permissions on the TLB entry */
544             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
545                 *prot |= PAGE_READ;
546             }
547             if ((pte & PTE_X)) {
548                 *prot |= PAGE_EXEC;
549             }
550             /* add write permission on stores or if the page is already dirty,
551                so that we TLB miss on later writes to update the dirty bit */
552             if ((pte & PTE_W) &&
553                     (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
554                 *prot |= PAGE_WRITE;
555             }
556             return TRANSLATE_SUCCESS;
557         }
558     }
559     return TRANSLATE_FAIL;
560 }
561 
562 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
563                                 MMUAccessType access_type, bool pmp_violation,
564                                 bool first_stage)
565 {
566     CPUState *cs = env_cpu(env);
567     int page_fault_exceptions;
568     if (first_stage) {
569         page_fault_exceptions =
570             get_field(env->satp, SATP_MODE) != VM_1_10_MBARE &&
571             !pmp_violation;
572     } else {
573         page_fault_exceptions =
574             get_field(env->hgatp, HGATP_MODE) != VM_1_10_MBARE &&
575             !pmp_violation;
576     }
577     switch (access_type) {
578     case MMU_INST_FETCH:
579         if (riscv_cpu_virt_enabled(env) && !first_stage) {
580             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
581         } else {
582             cs->exception_index = page_fault_exceptions ?
583                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
584         }
585         break;
586     case MMU_DATA_LOAD:
587         if (riscv_cpu_virt_enabled(env) && !first_stage) {
588             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
589         } else {
590             cs->exception_index = page_fault_exceptions ?
591                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
592         }
593         break;
594     case MMU_DATA_STORE:
595         if (riscv_cpu_virt_enabled(env) && !first_stage) {
596             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
597         } else {
598             cs->exception_index = page_fault_exceptions ?
599                 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
600         }
601         break;
602     default:
603         g_assert_not_reached();
604     }
605     env->badaddr = address;
606 }
607 
608 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
609 {
610     RISCVCPU *cpu = RISCV_CPU(cs);
611     CPURISCVState *env = &cpu->env;
612     hwaddr phys_addr;
613     int prot;
614     int mmu_idx = cpu_mmu_index(&cpu->env, false);
615 
616     if (get_physical_address(env, &phys_addr, &prot, addr, 0, mmu_idx,
617                              true, riscv_cpu_virt_enabled(env))) {
618         return -1;
619     }
620 
621     if (riscv_cpu_virt_enabled(env)) {
622         if (get_physical_address(env, &phys_addr, &prot, phys_addr,
623                                  0, mmu_idx, false, true)) {
624             return -1;
625         }
626     }
627 
628     return phys_addr;
629 }
630 
631 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
632                                      vaddr addr, unsigned size,
633                                      MMUAccessType access_type,
634                                      int mmu_idx, MemTxAttrs attrs,
635                                      MemTxResult response, uintptr_t retaddr)
636 {
637     RISCVCPU *cpu = RISCV_CPU(cs);
638     CPURISCVState *env = &cpu->env;
639 
640     if (access_type == MMU_DATA_STORE) {
641         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
642     } else {
643         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
644     }
645 
646     env->badaddr = addr;
647     riscv_raise_exception(&cpu->env, cs->exception_index, retaddr);
648 }
649 
650 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
651                                    MMUAccessType access_type, int mmu_idx,
652                                    uintptr_t retaddr)
653 {
654     RISCVCPU *cpu = RISCV_CPU(cs);
655     CPURISCVState *env = &cpu->env;
656     switch (access_type) {
657     case MMU_INST_FETCH:
658         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
659         break;
660     case MMU_DATA_LOAD:
661         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
662         break;
663     case MMU_DATA_STORE:
664         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
665         break;
666     default:
667         g_assert_not_reached();
668     }
669     env->badaddr = addr;
670     riscv_raise_exception(env, cs->exception_index, retaddr);
671 }
672 #endif
673 
674 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
675                         MMUAccessType access_type, int mmu_idx,
676                         bool probe, uintptr_t retaddr)
677 {
678     RISCVCPU *cpu = RISCV_CPU(cs);
679     CPURISCVState *env = &cpu->env;
680 #ifndef CONFIG_USER_ONLY
681     vaddr im_address;
682     hwaddr pa = 0;
683     int prot, prot2;
684     bool pmp_violation = false;
685     bool m_mode_two_stage = false;
686     bool hs_mode_two_stage = false;
687     bool first_stage_error = true;
688     int ret = TRANSLATE_FAIL;
689     int mode = mmu_idx;
690 
691     env->guest_phys_fault_addr = 0;
692 
693     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
694                   __func__, address, access_type, mmu_idx);
695 
696     /*
697      * Determine if we are in M mode and MPRV is set or in HS mode and SPRV is
698      * set and we want to access a virtulisation address.
699      */
700     if (riscv_has_ext(env, RVH)) {
701         m_mode_two_stage = env->priv == PRV_M &&
702                            access_type != MMU_INST_FETCH &&
703                            get_field(env->mstatus, MSTATUS_MPRV) &&
704                            MSTATUS_MPV_ISSET(env);
705 
706         hs_mode_two_stage = env->priv == PRV_S &&
707                             !riscv_cpu_virt_enabled(env) &&
708                             access_type != MMU_INST_FETCH &&
709                             get_field(env->hstatus, HSTATUS_SPRV) &&
710                             get_field(env->hstatus, HSTATUS_SPV);
711     }
712 
713     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
714         if (get_field(env->mstatus, MSTATUS_MPRV)) {
715             mode = get_field(env->mstatus, MSTATUS_MPP);
716         }
717     }
718 
719     if (riscv_cpu_virt_enabled(env) || m_mode_two_stage || hs_mode_two_stage) {
720         /* Two stage lookup */
721         ret = get_physical_address(env, &pa, &prot, address, access_type,
722                                    mmu_idx, true, true);
723 
724         qemu_log_mask(CPU_LOG_MMU,
725                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
726                       TARGET_FMT_plx " prot %d\n",
727                       __func__, address, ret, pa, prot);
728 
729         if (ret != TRANSLATE_FAIL) {
730             /* Second stage lookup */
731             im_address = pa;
732 
733             ret = get_physical_address(env, &pa, &prot2, im_address,
734                                        access_type, mmu_idx, false, true);
735 
736             qemu_log_mask(CPU_LOG_MMU,
737                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
738                     TARGET_FMT_plx " prot %d\n",
739                     __func__, im_address, ret, pa, prot2);
740 
741             prot &= prot2;
742 
743             if (riscv_feature(env, RISCV_FEATURE_PMP) &&
744                 (ret == TRANSLATE_SUCCESS) &&
745                 !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
746                 ret = TRANSLATE_PMP_FAIL;
747             }
748 
749             if (ret != TRANSLATE_SUCCESS) {
750                 /*
751                  * Guest physical address translation failed, this is a HS
752                  * level exception
753                  */
754                 first_stage_error = false;
755                 env->guest_phys_fault_addr = (im_address |
756                                               (address &
757                                                (TARGET_PAGE_SIZE - 1))) >> 2;
758             }
759         }
760     } else {
761         /* Single stage lookup */
762         ret = get_physical_address(env, &pa, &prot, address, access_type,
763                                    mmu_idx, true, false);
764 
765         qemu_log_mask(CPU_LOG_MMU,
766                       "%s address=%" VADDR_PRIx " ret %d physical "
767                       TARGET_FMT_plx " prot %d\n",
768                       __func__, address, ret, pa, prot);
769     }
770 
771     if (riscv_feature(env, RISCV_FEATURE_PMP) &&
772         (ret == TRANSLATE_SUCCESS) &&
773         !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
774         ret = TRANSLATE_PMP_FAIL;
775     }
776     if (ret == TRANSLATE_PMP_FAIL) {
777         pmp_violation = true;
778     }
779 
780     if (ret == TRANSLATE_SUCCESS) {
781         tlb_set_page(cs, address & TARGET_PAGE_MASK, pa & TARGET_PAGE_MASK,
782                      prot, mmu_idx, TARGET_PAGE_SIZE);
783         return true;
784     } else if (probe) {
785         return false;
786     } else {
787         raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error);
788         riscv_raise_exception(env, cs->exception_index, retaddr);
789     }
790 
791     return true;
792 
793 #else
794     switch (access_type) {
795     case MMU_INST_FETCH:
796         cs->exception_index = RISCV_EXCP_INST_PAGE_FAULT;
797         break;
798     case MMU_DATA_LOAD:
799         cs->exception_index = RISCV_EXCP_LOAD_PAGE_FAULT;
800         break;
801     case MMU_DATA_STORE:
802         cs->exception_index = RISCV_EXCP_STORE_PAGE_FAULT;
803         break;
804     default:
805         g_assert_not_reached();
806     }
807     env->badaddr = address;
808     cpu_loop_exit_restore(cs, retaddr);
809 #endif
810 }
811 
812 /*
813  * Handle Traps
814  *
815  * Adapted from Spike's processor_t::take_trap.
816  *
817  */
818 void riscv_cpu_do_interrupt(CPUState *cs)
819 {
820 #if !defined(CONFIG_USER_ONLY)
821 
822     RISCVCPU *cpu = RISCV_CPU(cs);
823     CPURISCVState *env = &cpu->env;
824     bool force_hs_execp = riscv_cpu_force_hs_excep_enabled(env);
825     target_ulong s;
826 
827     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
828      * so we mask off the MSB and separate into trap type and cause.
829      */
830     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
831     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
832     target_ulong deleg = async ? env->mideleg : env->medeleg;
833     target_ulong tval = 0;
834     target_ulong htval = 0;
835     target_ulong mtval2 = 0;
836 
837     if (!async) {
838         /* set tval to badaddr for traps with address information */
839         switch (cause) {
840         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
841         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
842         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
843             force_hs_execp = true;
844             /* fallthrough */
845         case RISCV_EXCP_INST_ADDR_MIS:
846         case RISCV_EXCP_INST_ACCESS_FAULT:
847         case RISCV_EXCP_LOAD_ADDR_MIS:
848         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
849         case RISCV_EXCP_LOAD_ACCESS_FAULT:
850         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
851         case RISCV_EXCP_INST_PAGE_FAULT:
852         case RISCV_EXCP_LOAD_PAGE_FAULT:
853         case RISCV_EXCP_STORE_PAGE_FAULT:
854             tval = env->badaddr;
855             break;
856         default:
857             break;
858         }
859         /* ecall is dispatched as one cause so translate based on mode */
860         if (cause == RISCV_EXCP_U_ECALL) {
861             assert(env->priv <= 3);
862 
863             if (env->priv == PRV_M) {
864                 cause = RISCV_EXCP_M_ECALL;
865             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
866                 cause = RISCV_EXCP_VS_ECALL;
867             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
868                 cause = RISCV_EXCP_S_ECALL;
869             } else if (env->priv == PRV_U) {
870                 cause = RISCV_EXCP_U_ECALL;
871             }
872         }
873     }
874 
875     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval, cause < 23 ?
876         (async ? riscv_intr_names : riscv_excp_names)[cause] : "(unknown)");
877 
878     if (env->priv <= PRV_S &&
879             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
880         /* handle the trap in S-mode */
881         if (riscv_has_ext(env, RVH)) {
882             target_ulong hdeleg = async ? env->hideleg : env->hedeleg;
883 
884             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1) &&
885                 !force_hs_execp) {
886                 /*
887                  * See if we need to adjust cause. Yes if its VS mode interrupt
888                  * no if hypervisor has delegated one of hs mode's interrupt
889                  */
890                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
891                     cause == IRQ_VS_EXT)
892                     cause = cause - 1;
893                 /* Trap to VS mode */
894             } else if (riscv_cpu_virt_enabled(env)) {
895                 /* Trap into HS mode, from virt */
896                 riscv_cpu_swap_hypervisor_regs(env);
897                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2V,
898                                          get_field(env->hstatus, HSTATUS_SPV));
899                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2P,
900                                          get_field(env->mstatus, SSTATUS_SPP));
901                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
902                                          riscv_cpu_virt_enabled(env));
903 
904                 htval = env->guest_phys_fault_addr;
905 
906                 riscv_cpu_set_virt_enabled(env, 0);
907                 riscv_cpu_set_force_hs_excep(env, 0);
908             } else {
909                 /* Trap into HS mode */
910                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2V,
911                                          get_field(env->hstatus, HSTATUS_SPV));
912                 env->hstatus = set_field(env->hstatus, HSTATUS_SP2P,
913                                          get_field(env->mstatus, SSTATUS_SPP));
914                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
915                                          riscv_cpu_virt_enabled(env));
916 
917                 htval = env->guest_phys_fault_addr;
918             }
919         }
920 
921         s = env->mstatus;
922         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
923         s = set_field(s, MSTATUS_SPP, env->priv);
924         s = set_field(s, MSTATUS_SIE, 0);
925         env->mstatus = s;
926         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
927         env->sepc = env->pc;
928         env->sbadaddr = tval;
929         env->htval = htval;
930         env->pc = (env->stvec >> 2 << 2) +
931             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
932         riscv_cpu_set_mode(env, PRV_S);
933     } else {
934         /* handle the trap in M-mode */
935         if (riscv_has_ext(env, RVH)) {
936             if (riscv_cpu_virt_enabled(env)) {
937                 riscv_cpu_swap_hypervisor_regs(env);
938             }
939 #ifdef TARGET_RISCV32
940             env->mstatush = set_field(env->mstatush, MSTATUS_MPV,
941                                        riscv_cpu_virt_enabled(env));
942             env->mstatush = set_field(env->mstatush, MSTATUS_MTL,
943                                        riscv_cpu_force_hs_excep_enabled(env));
944 #else
945             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
946                                       riscv_cpu_virt_enabled(env));
947             env->mstatus = set_field(env->mstatus, MSTATUS_MTL,
948                                       riscv_cpu_force_hs_excep_enabled(env));
949 #endif
950 
951             mtval2 = env->guest_phys_fault_addr;
952 
953             /* Trapping to M mode, virt is disabled */
954             riscv_cpu_set_virt_enabled(env, 0);
955             riscv_cpu_set_force_hs_excep(env, 0);
956         }
957 
958         s = env->mstatus;
959         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
960         s = set_field(s, MSTATUS_MPP, env->priv);
961         s = set_field(s, MSTATUS_MIE, 0);
962         env->mstatus = s;
963         env->mcause = cause | ~(((target_ulong)-1) >> async);
964         env->mepc = env->pc;
965         env->mbadaddr = tval;
966         env->mtval2 = mtval2;
967         env->pc = (env->mtvec >> 2 << 2) +
968             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
969         riscv_cpu_set_mode(env, PRV_M);
970     }
971 
972     /* NOTE: it is not necessary to yield load reservations here. It is only
973      * necessary for an SC from "another hart" to cause a load reservation
974      * to be yielded. Refer to the memory consistency model section of the
975      * RISC-V ISA Specification.
976      */
977 
978 #endif
979     cs->exception_index = EXCP_NONE; /* mark handled to qemu */
980 }
981