xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision c51a3f5d)
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)(void))
280 {
281     env->rdtime_fn = fn;
282 }
283 
284 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv)
285 {
286     if (newpriv > PRV_M) {
287         g_assert_not_reached();
288     }
289     if (newpriv == PRV_H) {
290         newpriv = PRV_U;
291     }
292     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
293     env->priv = newpriv;
294 
295     /*
296      * Clear the load reservation - otherwise a reservation placed in one
297      * context/process can be used by another, resulting in an SC succeeding
298      * incorrectly. Version 2.2 of the ISA specification explicitly requires
299      * this behaviour, while later revisions say that the kernel "should" use
300      * an SC instruction to force the yielding of a load reservation on a
301      * preemptive context switch. As a result, do both.
302      */
303     env->load_res = -1;
304 }
305 
306 /* get_physical_address - get the physical address for this virtual address
307  *
308  * Do a page table walk to obtain the physical address corresponding to a
309  * virtual address. Returns 0 if the translation was successful
310  *
311  * Adapted from Spike's mmu_t::translate and mmu_t::walk
312  *
313  * @env: CPURISCVState
314  * @physical: This will be set to the calculated physical address
315  * @prot: The returned protection attributes
316  * @addr: The virtual address to be translated
317  * @access_type: The type of MMU access
318  * @mmu_idx: Indicates current privilege level
319  * @first_stage: Are we in first stage translation?
320  *               Second stage is used for hypervisor guest translation
321  * @two_stage: Are we going to perform two stage translation
322  */
323 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
324                                 int *prot, target_ulong addr,
325                                 int access_type, int mmu_idx,
326                                 bool first_stage, bool two_stage)
327 {
328     /* NOTE: the env->pc value visible here will not be
329      * correct, but the value visible to the exception handler
330      * (riscv_cpu_do_interrupt) is correct */
331     MemTxResult res;
332     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
333     int mode = mmu_idx;
334     bool use_background = false;
335 
336     /*
337      * Check if we should use the background registers for the two
338      * stage translation. We don't need to check if we actually need
339      * two stage translation as that happened before this function
340      * was called. Background registers will be used if the guest has
341      * forced a two stage translation to be on (in HS or M mode).
342      */
343     if (riscv_cpu_two_stage_lookup(env) && access_type != MMU_INST_FETCH) {
344         use_background = true;
345     }
346 
347     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
348         if (get_field(env->mstatus, MSTATUS_MPRV)) {
349             mode = get_field(env->mstatus, MSTATUS_MPP);
350         }
351     }
352 
353     if (first_stage == false) {
354         /* We are in stage 2 translation, this is similar to stage 1. */
355         /* Stage 2 is always taken as U-mode */
356         mode = PRV_U;
357     }
358 
359     if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) {
360         *physical = addr;
361         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
362         return TRANSLATE_SUCCESS;
363     }
364 
365     *prot = 0;
366 
367     hwaddr base;
368     int levels, ptidxbits, ptesize, vm, sum, mxr, widened;
369 
370     if (first_stage == true) {
371         mxr = get_field(env->mstatus, MSTATUS_MXR);
372     } else {
373         mxr = get_field(env->vsstatus, MSTATUS_MXR);
374     }
375 
376     if (first_stage == true) {
377         if (use_background) {
378             base = (hwaddr)get_field(env->vsatp, SATP_PPN) << PGSHIFT;
379             vm = get_field(env->vsatp, SATP_MODE);
380         } else {
381             base = (hwaddr)get_field(env->satp, SATP_PPN) << PGSHIFT;
382             vm = get_field(env->satp, SATP_MODE);
383         }
384         widened = 0;
385     } else {
386         base = (hwaddr)get_field(env->hgatp, HGATP_PPN) << PGSHIFT;
387         vm = get_field(env->hgatp, HGATP_MODE);
388         widened = 2;
389     }
390     sum = get_field(env->mstatus, MSTATUS_SUM);
391     switch (vm) {
392     case VM_1_10_SV32:
393       levels = 2; ptidxbits = 10; ptesize = 4; break;
394     case VM_1_10_SV39:
395       levels = 3; ptidxbits = 9; ptesize = 8; break;
396     case VM_1_10_SV48:
397       levels = 4; ptidxbits = 9; ptesize = 8; break;
398     case VM_1_10_SV57:
399       levels = 5; ptidxbits = 9; ptesize = 8; break;
400     case VM_1_10_MBARE:
401         *physical = addr;
402         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
403         return TRANSLATE_SUCCESS;
404     default:
405       g_assert_not_reached();
406     }
407 
408     CPUState *cs = env_cpu(env);
409     int va_bits = PGSHIFT + levels * ptidxbits + widened;
410     target_ulong mask, masked_msbs;
411 
412     if (TARGET_LONG_BITS > (va_bits - 1)) {
413         mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1;
414     } else {
415         mask = 0;
416     }
417     masked_msbs = (addr >> (va_bits - 1)) & mask;
418 
419     if (masked_msbs != 0 && masked_msbs != mask) {
420         return TRANSLATE_FAIL;
421     }
422 
423     int ptshift = (levels - 1) * ptidxbits;
424     int i;
425 
426 #if !TCG_OVERSIZED_GUEST
427 restart:
428 #endif
429     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
430         target_ulong idx;
431         if (i == 0) {
432             idx = (addr >> (PGSHIFT + ptshift)) &
433                            ((1 << (ptidxbits + widened)) - 1);
434         } else {
435             idx = (addr >> (PGSHIFT + ptshift)) &
436                            ((1 << ptidxbits) - 1);
437         }
438 
439         /* check that physical address of PTE is legal */
440         hwaddr pte_addr;
441 
442         if (two_stage && first_stage) {
443             int vbase_prot;
444             hwaddr vbase;
445 
446             /* Do the second stage translation on the base PTE address. */
447             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
448                                                  base, MMU_DATA_LOAD,
449                                                  mmu_idx, false, true);
450 
451             if (vbase_ret != TRANSLATE_SUCCESS) {
452                 return vbase_ret;
453             }
454 
455             pte_addr = vbase + idx * ptesize;
456         } else {
457             pte_addr = base + idx * ptesize;
458         }
459 
460         if (riscv_feature(env, RISCV_FEATURE_PMP) &&
461             !pmp_hart_has_privs(env, pte_addr, sizeof(target_ulong),
462             1 << MMU_DATA_LOAD, PRV_S)) {
463             return TRANSLATE_PMP_FAIL;
464         }
465 
466 #if defined(TARGET_RISCV32)
467         target_ulong pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
468 #elif defined(TARGET_RISCV64)
469         target_ulong pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
470 #endif
471         if (res != MEMTX_OK) {
472             return TRANSLATE_FAIL;
473         }
474 
475         hwaddr ppn = pte >> PTE_PPN_SHIFT;
476 
477         if (!(pte & PTE_V)) {
478             /* Invalid PTE */
479             return TRANSLATE_FAIL;
480         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
481             /* Inner PTE, continue walking */
482             base = ppn << PGSHIFT;
483         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
484             /* Reserved leaf PTE flags: PTE_W */
485             return TRANSLATE_FAIL;
486         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
487             /* Reserved leaf PTE flags: PTE_W + PTE_X */
488             return TRANSLATE_FAIL;
489         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
490                    (!sum || access_type == MMU_INST_FETCH))) {
491             /* User PTE flags when not U mode and mstatus.SUM is not set,
492                or the access type is an instruction fetch */
493             return TRANSLATE_FAIL;
494         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
495             /* Supervisor PTE flags when not S mode */
496             return TRANSLATE_FAIL;
497         } else if (ppn & ((1ULL << ptshift) - 1)) {
498             /* Misaligned PPN */
499             return TRANSLATE_FAIL;
500         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
501                    ((pte & PTE_X) && mxr))) {
502             /* Read access check failed */
503             return TRANSLATE_FAIL;
504         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
505             /* Write access check failed */
506             return TRANSLATE_FAIL;
507         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
508             /* Fetch access check failed */
509             return TRANSLATE_FAIL;
510         } else {
511             /* if necessary, set accessed and dirty bits. */
512             target_ulong updated_pte = pte | PTE_A |
513                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
514 
515             /* Page table updates need to be atomic with MTTCG enabled */
516             if (updated_pte != pte) {
517                 /*
518                  * - if accessed or dirty bits need updating, and the PTE is
519                  *   in RAM, then we do so atomically with a compare and swap.
520                  * - if the PTE is in IO space or ROM, then it can't be updated
521                  *   and we return TRANSLATE_FAIL.
522                  * - if the PTE changed by the time we went to update it, then
523                  *   it is no longer valid and we must re-walk the page table.
524                  */
525                 MemoryRegion *mr;
526                 hwaddr l = sizeof(target_ulong), addr1;
527                 mr = address_space_translate(cs->as, pte_addr,
528                     &addr1, &l, false, MEMTXATTRS_UNSPECIFIED);
529                 if (memory_region_is_ram(mr)) {
530                     target_ulong *pte_pa =
531                         qemu_map_ram_ptr(mr->ram_block, addr1);
532 #if TCG_OVERSIZED_GUEST
533                     /* MTTCG is not enabled on oversized TCG guests so
534                      * page table updates do not need to be atomic */
535                     *pte_pa = pte = updated_pte;
536 #else
537                     target_ulong old_pte =
538                         atomic_cmpxchg(pte_pa, pte, updated_pte);
539                     if (old_pte != pte) {
540                         goto restart;
541                     } else {
542                         pte = updated_pte;
543                     }
544 #endif
545                 } else {
546                     /* misconfigured PTE in ROM (AD bits are not preset) or
547                      * PTE is in IO space and can't be updated atomically */
548                     return TRANSLATE_FAIL;
549                 }
550             }
551 
552             /* for superpage mappings, make a fake leaf PTE for the TLB's
553                benefit. */
554             target_ulong vpn = addr >> PGSHIFT;
555             *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) |
556                         (addr & ~TARGET_PAGE_MASK);
557 
558             /* set permissions on the TLB entry */
559             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
560                 *prot |= PAGE_READ;
561             }
562             if ((pte & PTE_X)) {
563                 *prot |= PAGE_EXEC;
564             }
565             /* add write permission on stores or if the page is already dirty,
566                so that we TLB miss on later writes to update the dirty bit */
567             if ((pte & PTE_W) &&
568                     (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
569                 *prot |= PAGE_WRITE;
570             }
571             return TRANSLATE_SUCCESS;
572         }
573     }
574     return TRANSLATE_FAIL;
575 }
576 
577 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
578                                 MMUAccessType access_type, bool pmp_violation,
579                                 bool first_stage)
580 {
581     CPUState *cs = env_cpu(env);
582     int page_fault_exceptions;
583     if (first_stage) {
584         page_fault_exceptions =
585             get_field(env->satp, SATP_MODE) != VM_1_10_MBARE &&
586             !pmp_violation;
587     } else {
588         page_fault_exceptions =
589             get_field(env->hgatp, HGATP_MODE) != VM_1_10_MBARE &&
590             !pmp_violation;
591     }
592     switch (access_type) {
593     case MMU_INST_FETCH:
594         if (riscv_cpu_virt_enabled(env) && !first_stage) {
595             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
596         } else {
597             cs->exception_index = page_fault_exceptions ?
598                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
599         }
600         break;
601     case MMU_DATA_LOAD:
602         if ((riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(env)) &&
603             !first_stage) {
604             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
605         } else {
606             cs->exception_index = page_fault_exceptions ?
607                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
608         }
609         break;
610     case MMU_DATA_STORE:
611         if ((riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(env)) &&
612             !first_stage) {
613             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
614         } else {
615             cs->exception_index = page_fault_exceptions ?
616                 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
617         }
618         break;
619     default:
620         g_assert_not_reached();
621     }
622     env->badaddr = address;
623 }
624 
625 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
626 {
627     RISCVCPU *cpu = RISCV_CPU(cs);
628     CPURISCVState *env = &cpu->env;
629     hwaddr phys_addr;
630     int prot;
631     int mmu_idx = cpu_mmu_index(&cpu->env, false);
632 
633     if (get_physical_address(env, &phys_addr, &prot, addr, 0, mmu_idx,
634                              true, riscv_cpu_virt_enabled(env))) {
635         return -1;
636     }
637 
638     if (riscv_cpu_virt_enabled(env)) {
639         if (get_physical_address(env, &phys_addr, &prot, phys_addr,
640                                  0, mmu_idx, false, true)) {
641             return -1;
642         }
643     }
644 
645     return phys_addr & TARGET_PAGE_MASK;
646 }
647 
648 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
649                                      vaddr addr, unsigned size,
650                                      MMUAccessType access_type,
651                                      int mmu_idx, MemTxAttrs attrs,
652                                      MemTxResult response, uintptr_t retaddr)
653 {
654     RISCVCPU *cpu = RISCV_CPU(cs);
655     CPURISCVState *env = &cpu->env;
656 
657     if (access_type == MMU_DATA_STORE) {
658         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
659     } else {
660         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
661     }
662 
663     env->badaddr = addr;
664     riscv_raise_exception(&cpu->env, cs->exception_index, retaddr);
665 }
666 
667 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
668                                    MMUAccessType access_type, int mmu_idx,
669                                    uintptr_t retaddr)
670 {
671     RISCVCPU *cpu = RISCV_CPU(cs);
672     CPURISCVState *env = &cpu->env;
673     switch (access_type) {
674     case MMU_INST_FETCH:
675         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
676         break;
677     case MMU_DATA_LOAD:
678         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
679         break;
680     case MMU_DATA_STORE:
681         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
682         break;
683     default:
684         g_assert_not_reached();
685     }
686     env->badaddr = addr;
687     riscv_raise_exception(env, cs->exception_index, retaddr);
688 }
689 #endif
690 
691 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
692                         MMUAccessType access_type, int mmu_idx,
693                         bool probe, uintptr_t retaddr)
694 {
695     RISCVCPU *cpu = RISCV_CPU(cs);
696     CPURISCVState *env = &cpu->env;
697 #ifndef CONFIG_USER_ONLY
698     vaddr im_address;
699     hwaddr pa = 0;
700     int prot, prot2;
701     bool pmp_violation = false;
702     bool first_stage_error = true;
703     int ret = TRANSLATE_FAIL;
704     int mode = mmu_idx;
705     target_ulong tlb_size = 0;
706 
707     env->guest_phys_fault_addr = 0;
708 
709     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
710                   __func__, address, access_type, mmu_idx);
711 
712     if (mode == PRV_M && access_type != MMU_INST_FETCH) {
713         if (get_field(env->mstatus, MSTATUS_MPRV)) {
714             mode = get_field(env->mstatus, MSTATUS_MPP);
715         }
716     }
717 
718     if (riscv_has_ext(env, RVH) && env->priv == PRV_M &&
719         access_type != MMU_INST_FETCH &&
720         get_field(env->mstatus, MSTATUS_MPRV) &&
721         MSTATUS_MPV_ISSET(env)) {
722         riscv_cpu_set_two_stage_lookup(env, true);
723     }
724 
725     if (riscv_cpu_virt_enabled(env) ||
726         (riscv_cpu_two_stage_lookup(env) && access_type != MMU_INST_FETCH)) {
727         /* Two stage lookup */
728         ret = get_physical_address(env, &pa, &prot, address, access_type,
729                                    mmu_idx, true, true);
730 
731         qemu_log_mask(CPU_LOG_MMU,
732                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
733                       TARGET_FMT_plx " prot %d\n",
734                       __func__, address, ret, pa, prot);
735 
736         if (ret != TRANSLATE_FAIL) {
737             /* Second stage lookup */
738             im_address = pa;
739 
740             ret = get_physical_address(env, &pa, &prot2, im_address,
741                                        access_type, mmu_idx, false, true);
742 
743             qemu_log_mask(CPU_LOG_MMU,
744                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
745                     TARGET_FMT_plx " prot %d\n",
746                     __func__, im_address, ret, pa, prot2);
747 
748             prot &= prot2;
749 
750             if (riscv_feature(env, RISCV_FEATURE_PMP) &&
751                 (ret == TRANSLATE_SUCCESS) &&
752                 !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
753                 ret = TRANSLATE_PMP_FAIL;
754             }
755 
756             if (ret != TRANSLATE_SUCCESS) {
757                 /*
758                  * Guest physical address translation failed, this is a HS
759                  * level exception
760                  */
761                 first_stage_error = false;
762                 env->guest_phys_fault_addr = (im_address |
763                                               (address &
764                                                (TARGET_PAGE_SIZE - 1))) >> 2;
765             }
766         }
767     } else {
768         /* Single stage lookup */
769         ret = get_physical_address(env, &pa, &prot, address, access_type,
770                                    mmu_idx, true, false);
771 
772         qemu_log_mask(CPU_LOG_MMU,
773                       "%s address=%" VADDR_PRIx " ret %d physical "
774                       TARGET_FMT_plx " prot %d\n",
775                       __func__, address, ret, pa, prot);
776     }
777 
778     /* We did the two stage lookup based on MPRV, unset the lookup */
779     if (riscv_has_ext(env, RVH) && env->priv == PRV_M &&
780         access_type != MMU_INST_FETCH &&
781         get_field(env->mstatus, MSTATUS_MPRV) &&
782         MSTATUS_MPV_ISSET(env)) {
783         riscv_cpu_set_two_stage_lookup(env, false);
784     }
785 
786     if (riscv_feature(env, RISCV_FEATURE_PMP) &&
787         (ret == TRANSLATE_SUCCESS) &&
788         !pmp_hart_has_privs(env, pa, size, 1 << access_type, mode)) {
789         ret = TRANSLATE_PMP_FAIL;
790     }
791     if (ret == TRANSLATE_PMP_FAIL) {
792         pmp_violation = true;
793     }
794 
795     if (ret == TRANSLATE_SUCCESS) {
796         if (pmp_is_range_in_tlb(env, pa & TARGET_PAGE_MASK, &tlb_size)) {
797             tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
798                          prot, mmu_idx, tlb_size);
799         } else {
800             tlb_set_page(cs, address & TARGET_PAGE_MASK, pa & TARGET_PAGE_MASK,
801                          prot, mmu_idx, TARGET_PAGE_SIZE);
802         }
803         return true;
804     } else if (probe) {
805         return false;
806     } else {
807         raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error);
808         riscv_raise_exception(env, cs->exception_index, retaddr);
809     }
810 
811     return true;
812 
813 #else
814     switch (access_type) {
815     case MMU_INST_FETCH:
816         cs->exception_index = RISCV_EXCP_INST_PAGE_FAULT;
817         break;
818     case MMU_DATA_LOAD:
819         cs->exception_index = RISCV_EXCP_LOAD_PAGE_FAULT;
820         break;
821     case MMU_DATA_STORE:
822         cs->exception_index = RISCV_EXCP_STORE_PAGE_FAULT;
823         break;
824     default:
825         g_assert_not_reached();
826     }
827     env->badaddr = address;
828     cpu_loop_exit_restore(cs, retaddr);
829 #endif
830 }
831 
832 /*
833  * Handle Traps
834  *
835  * Adapted from Spike's processor_t::take_trap.
836  *
837  */
838 void riscv_cpu_do_interrupt(CPUState *cs)
839 {
840 #if !defined(CONFIG_USER_ONLY)
841 
842     RISCVCPU *cpu = RISCV_CPU(cs);
843     CPURISCVState *env = &cpu->env;
844     bool force_hs_execp = riscv_cpu_force_hs_excep_enabled(env);
845     target_ulong s;
846 
847     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
848      * so we mask off the MSB and separate into trap type and cause.
849      */
850     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
851     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
852     target_ulong deleg = async ? env->mideleg : env->medeleg;
853     target_ulong tval = 0;
854     target_ulong htval = 0;
855     target_ulong mtval2 = 0;
856 
857     if (!async) {
858         /* set tval to badaddr for traps with address information */
859         switch (cause) {
860         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
861         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
862         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
863             force_hs_execp = true;
864             /* fallthrough */
865         case RISCV_EXCP_INST_ADDR_MIS:
866         case RISCV_EXCP_INST_ACCESS_FAULT:
867         case RISCV_EXCP_LOAD_ADDR_MIS:
868         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
869         case RISCV_EXCP_LOAD_ACCESS_FAULT:
870         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
871         case RISCV_EXCP_INST_PAGE_FAULT:
872         case RISCV_EXCP_LOAD_PAGE_FAULT:
873         case RISCV_EXCP_STORE_PAGE_FAULT:
874             tval = env->badaddr;
875             break;
876         default:
877             break;
878         }
879         /* ecall is dispatched as one cause so translate based on mode */
880         if (cause == RISCV_EXCP_U_ECALL) {
881             assert(env->priv <= 3);
882 
883             if (env->priv == PRV_M) {
884                 cause = RISCV_EXCP_M_ECALL;
885             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
886                 cause = RISCV_EXCP_VS_ECALL;
887             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
888                 cause = RISCV_EXCP_S_ECALL;
889             } else if (env->priv == PRV_U) {
890                 cause = RISCV_EXCP_U_ECALL;
891             }
892         }
893     }
894 
895     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
896         riscv_cpu_get_trap_name(cause, async));
897 
898     if (env->priv <= PRV_S &&
899             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
900         /* handle the trap in S-mode */
901         if (riscv_has_ext(env, RVH)) {
902             target_ulong hdeleg = async ? env->hideleg : env->hedeleg;
903 
904             if ((riscv_cpu_virt_enabled(env) ||
905                  riscv_cpu_two_stage_lookup(env)) && tval) {
906                 /*
907                  * If we are writing a guest virtual address to stval, set
908                  * this to 1. If we are trapping to VS we will set this to 0
909                  * later.
910                  */
911                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 1);
912             } else {
913                 /* For other HS-mode traps, we set this to 0. */
914                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0);
915             }
916 
917             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1) &&
918                 !force_hs_execp) {
919                 /* Trap to VS mode */
920                 /*
921                  * See if we need to adjust cause. Yes if its VS mode interrupt
922                  * no if hypervisor has delegated one of hs mode's interrupt
923                  */
924                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
925                     cause == IRQ_VS_EXT) {
926                     cause = cause - 1;
927                 }
928                 env->hstatus = set_field(env->hstatus, HSTATUS_GVA, 0);
929             } else if (riscv_cpu_virt_enabled(env)) {
930                 /* Trap into HS mode, from virt */
931                 riscv_cpu_swap_hypervisor_regs(env);
932                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
933                                          get_field(env->mstatus, SSTATUS_SPP));
934                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
935                                          riscv_cpu_virt_enabled(env));
936 
937                 htval = env->guest_phys_fault_addr;
938 
939                 riscv_cpu_set_virt_enabled(env, 0);
940                 riscv_cpu_set_force_hs_excep(env, 0);
941             } else {
942                 /* Trap into HS mode */
943                 if (!riscv_cpu_two_stage_lookup(env)) {
944                     env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
945                                              riscv_cpu_virt_enabled(env));
946                 }
947                 riscv_cpu_set_two_stage_lookup(env, false);
948                 htval = env->guest_phys_fault_addr;
949             }
950         }
951 
952         s = env->mstatus;
953         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
954         s = set_field(s, MSTATUS_SPP, env->priv);
955         s = set_field(s, MSTATUS_SIE, 0);
956         env->mstatus = s;
957         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
958         env->sepc = env->pc;
959         env->sbadaddr = tval;
960         env->htval = htval;
961         env->pc = (env->stvec >> 2 << 2) +
962             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
963         riscv_cpu_set_mode(env, PRV_S);
964     } else {
965         /* handle the trap in M-mode */
966         if (riscv_has_ext(env, RVH)) {
967             if (riscv_cpu_virt_enabled(env)) {
968                 riscv_cpu_swap_hypervisor_regs(env);
969             }
970 #ifdef TARGET_RISCV32
971             env->mstatush = set_field(env->mstatush, MSTATUS_MPV,
972                                        riscv_cpu_virt_enabled(env));
973             if (riscv_cpu_virt_enabled(env) && tval) {
974                 env->mstatush = set_field(env->mstatush, MSTATUS_GVA, 1);
975             }
976 #else
977             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
978                                       riscv_cpu_virt_enabled(env));
979             if (riscv_cpu_virt_enabled(env) && tval) {
980                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
981             }
982 #endif
983 
984             mtval2 = env->guest_phys_fault_addr;
985 
986             /* Trapping to M mode, virt is disabled */
987             riscv_cpu_set_virt_enabled(env, 0);
988             riscv_cpu_set_force_hs_excep(env, 0);
989         }
990 
991         s = env->mstatus;
992         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
993         s = set_field(s, MSTATUS_MPP, env->priv);
994         s = set_field(s, MSTATUS_MIE, 0);
995         env->mstatus = s;
996         env->mcause = cause | ~(((target_ulong)-1) >> async);
997         env->mepc = env->pc;
998         env->mbadaddr = tval;
999         env->mtval2 = mtval2;
1000         env->pc = (env->mtvec >> 2 << 2) +
1001             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
1002         riscv_cpu_set_mode(env, PRV_M);
1003     }
1004 
1005     /* NOTE: it is not necessary to yield load reservations here. It is only
1006      * necessary for an SC from "another hart" to cause a load reservation
1007      * to be yielded. Refer to the memory consistency model section of the
1008      * RISC-V ISA Specification.
1009      */
1010 
1011 #endif
1012     cs->exception_index = EXCP_NONE; /* mark handled to qemu */
1013 }
1014