xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision 355d5584)
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 "instmap.h"
26 #include "tcg/tcg-op.h"
27 #include "trace.h"
28 #include "semihosting/common-semi.h"
29 
30 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
31 {
32 #ifdef CONFIG_USER_ONLY
33     return 0;
34 #else
35     return env->priv;
36 #endif
37 }
38 
39 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
40                           target_ulong *cs_base, uint32_t *pflags)
41 {
42     CPUState *cs = env_cpu(env);
43     RISCVCPU *cpu = RISCV_CPU(cs);
44 
45     uint32_t flags = 0;
46 
47     *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc;
48     *cs_base = 0;
49 
50     if (riscv_has_ext(env, RVV) || cpu->cfg.ext_zve32f || cpu->cfg.ext_zve64f) {
51         /*
52          * If env->vl equals to VLMAX, we can use generic vector operation
53          * expanders (GVEC) to accerlate the vector operations.
54          * However, as LMUL could be a fractional number. The maximum
55          * vector size can be operated might be less than 8 bytes,
56          * which is not supported by GVEC. So we set vl_eq_vlmax flag to true
57          * only when maxsz >= 8 bytes.
58          */
59         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
60         uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW);
61         uint32_t maxsz = vlmax << sew;
62         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) &&
63                            (maxsz >= 8);
64         flags = FIELD_DP32(flags, TB_FLAGS, VILL, env->vill);
65         flags = FIELD_DP32(flags, TB_FLAGS, SEW, sew);
66         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
67                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
68         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
69         flags = FIELD_DP32(flags, TB_FLAGS, VTA,
70                     FIELD_EX64(env->vtype, VTYPE, VTA));
71         flags = FIELD_DP32(flags, TB_FLAGS, VMA,
72                     FIELD_EX64(env->vtype, VTYPE, VMA));
73     } else {
74         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
75     }
76 
77 #ifdef CONFIG_USER_ONLY
78     flags |= TB_FLAGS_MSTATUS_FS;
79     flags |= TB_FLAGS_MSTATUS_VS;
80 #else
81     flags |= cpu_mmu_index(env, 0);
82     if (riscv_cpu_fp_enabled(env)) {
83         flags |= env->mstatus & MSTATUS_FS;
84     }
85 
86     if (riscv_cpu_vector_enabled(env)) {
87         flags |= env->mstatus & MSTATUS_VS;
88     }
89 
90     if (riscv_has_ext(env, RVH)) {
91         if (env->priv == PRV_M ||
92             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
93             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
94                 get_field(env->hstatus, HSTATUS_HU))) {
95             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
96         }
97 
98         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS,
99                            get_field(env->mstatus_hs, MSTATUS_FS));
100 
101         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS,
102                            get_field(env->mstatus_hs, MSTATUS_VS));
103     }
104 #endif
105 
106     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
107     if (env->cur_pmmask < (env->xl == MXL_RV32 ? UINT32_MAX : UINT64_MAX)) {
108         flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
109     }
110     if (env->cur_pmbase != 0) {
111         flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1);
112     }
113 
114     *pflags = flags;
115 }
116 
117 void riscv_cpu_update_mask(CPURISCVState *env)
118 {
119     target_ulong mask = -1, base = 0;
120     /*
121      * TODO: Current RVJ spec does not specify
122      * how the extension interacts with XLEN.
123      */
124 #ifndef CONFIG_USER_ONLY
125     if (riscv_has_ext(env, RVJ)) {
126         switch (env->priv) {
127         case PRV_M:
128             if (env->mmte & M_PM_ENABLE) {
129                 mask = env->mpmmask;
130                 base = env->mpmbase;
131             }
132             break;
133         case PRV_S:
134             if (env->mmte & S_PM_ENABLE) {
135                 mask = env->spmmask;
136                 base = env->spmbase;
137             }
138             break;
139         case PRV_U:
140             if (env->mmte & U_PM_ENABLE) {
141                 mask = env->upmmask;
142                 base = env->upmbase;
143             }
144             break;
145         default:
146             g_assert_not_reached();
147         }
148     }
149 #endif
150     if (env->xl == MXL_RV32) {
151         env->cur_pmmask = mask & UINT32_MAX;
152         env->cur_pmbase = base & UINT32_MAX;
153     } else {
154         env->cur_pmmask = mask;
155         env->cur_pmbase = base;
156     }
157 }
158 
159 #ifndef CONFIG_USER_ONLY
160 
161 /*
162  * The HS-mode is allowed to configure priority only for the
163  * following VS-mode local interrupts:
164  *
165  * 0  (Reserved interrupt, reads as zero)
166  * 1  Supervisor software interrupt
167  * 4  (Reserved interrupt, reads as zero)
168  * 5  Supervisor timer interrupt
169  * 8  (Reserved interrupt, reads as zero)
170  * 13 (Reserved interrupt)
171  * 14 "
172  * 15 "
173  * 16 "
174  * 17 "
175  * 18 "
176  * 19 "
177  * 20 "
178  * 21 "
179  * 22 "
180  * 23 "
181  */
182 
183 static const int hviprio_index2irq[] = {
184     0, 1, 4, 5, 8, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 };
185 static const int hviprio_index2rdzero[] = {
186     1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
187 
188 int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero)
189 {
190     if (index < 0 || ARRAY_SIZE(hviprio_index2irq) <= index) {
191         return -EINVAL;
192     }
193 
194     if (out_irq) {
195         *out_irq = hviprio_index2irq[index];
196     }
197 
198     if (out_rdzero) {
199         *out_rdzero = hviprio_index2rdzero[index];
200     }
201 
202     return 0;
203 }
204 
205 /*
206  * Default priorities of local interrupts are defined in the
207  * RISC-V Advanced Interrupt Architecture specification.
208  *
209  * ----------------------------------------------------------------
210  *  Default  |
211  *  Priority | Major Interrupt Numbers
212  * ----------------------------------------------------------------
213  *  Highest  | 47, 23, 46, 45, 22, 44,
214  *           | 43, 21, 42, 41, 20, 40
215  *           |
216  *           | 11 (0b),  3 (03),  7 (07)
217  *           |  9 (09),  1 (01),  5 (05)
218  *           | 12 (0c)
219  *           | 10 (0a),  2 (02),  6 (06)
220  *           |
221  *           | 39, 19, 38, 37, 18, 36,
222  *  Lowest   | 35, 17, 34, 33, 16, 32
223  * ----------------------------------------------------------------
224  */
225 static const uint8_t default_iprio[64] = {
226  /* Custom interrupts 48 to 63 */
227  [63] = IPRIO_MMAXIPRIO,
228  [62] = IPRIO_MMAXIPRIO,
229  [61] = IPRIO_MMAXIPRIO,
230  [60] = IPRIO_MMAXIPRIO,
231  [59] = IPRIO_MMAXIPRIO,
232  [58] = IPRIO_MMAXIPRIO,
233  [57] = IPRIO_MMAXIPRIO,
234  [56] = IPRIO_MMAXIPRIO,
235  [55] = IPRIO_MMAXIPRIO,
236  [54] = IPRIO_MMAXIPRIO,
237  [53] = IPRIO_MMAXIPRIO,
238  [52] = IPRIO_MMAXIPRIO,
239  [51] = IPRIO_MMAXIPRIO,
240  [50] = IPRIO_MMAXIPRIO,
241  [49] = IPRIO_MMAXIPRIO,
242  [48] = IPRIO_MMAXIPRIO,
243 
244  /* Custom interrupts 24 to 31 */
245  [31] = IPRIO_MMAXIPRIO,
246  [30] = IPRIO_MMAXIPRIO,
247  [29] = IPRIO_MMAXIPRIO,
248  [28] = IPRIO_MMAXIPRIO,
249  [27] = IPRIO_MMAXIPRIO,
250  [26] = IPRIO_MMAXIPRIO,
251  [25] = IPRIO_MMAXIPRIO,
252  [24] = IPRIO_MMAXIPRIO,
253 
254  [47] = IPRIO_DEFAULT_UPPER,
255  [23] = IPRIO_DEFAULT_UPPER + 1,
256  [46] = IPRIO_DEFAULT_UPPER + 2,
257  [45] = IPRIO_DEFAULT_UPPER + 3,
258  [22] = IPRIO_DEFAULT_UPPER + 4,
259  [44] = IPRIO_DEFAULT_UPPER + 5,
260 
261  [43] = IPRIO_DEFAULT_UPPER + 6,
262  [21] = IPRIO_DEFAULT_UPPER + 7,
263  [42] = IPRIO_DEFAULT_UPPER + 8,
264  [41] = IPRIO_DEFAULT_UPPER + 9,
265  [20] = IPRIO_DEFAULT_UPPER + 10,
266  [40] = IPRIO_DEFAULT_UPPER + 11,
267 
268  [11] = IPRIO_DEFAULT_M,
269  [3]  = IPRIO_DEFAULT_M + 1,
270  [7]  = IPRIO_DEFAULT_M + 2,
271 
272  [9]  = IPRIO_DEFAULT_S,
273  [1]  = IPRIO_DEFAULT_S + 1,
274  [5]  = IPRIO_DEFAULT_S + 2,
275 
276  [12] = IPRIO_DEFAULT_SGEXT,
277 
278  [10] = IPRIO_DEFAULT_VS,
279  [2]  = IPRIO_DEFAULT_VS + 1,
280  [6]  = IPRIO_DEFAULT_VS + 2,
281 
282  [39] = IPRIO_DEFAULT_LOWER,
283  [19] = IPRIO_DEFAULT_LOWER + 1,
284  [38] = IPRIO_DEFAULT_LOWER + 2,
285  [37] = IPRIO_DEFAULT_LOWER + 3,
286  [18] = IPRIO_DEFAULT_LOWER + 4,
287  [36] = IPRIO_DEFAULT_LOWER + 5,
288 
289  [35] = IPRIO_DEFAULT_LOWER + 6,
290  [17] = IPRIO_DEFAULT_LOWER + 7,
291  [34] = IPRIO_DEFAULT_LOWER + 8,
292  [33] = IPRIO_DEFAULT_LOWER + 9,
293  [16] = IPRIO_DEFAULT_LOWER + 10,
294  [32] = IPRIO_DEFAULT_LOWER + 11,
295 };
296 
297 uint8_t riscv_cpu_default_priority(int irq)
298 {
299     if (irq < 0 || irq > 63) {
300         return IPRIO_MMAXIPRIO;
301     }
302 
303     return default_iprio[irq] ? default_iprio[irq] : IPRIO_MMAXIPRIO;
304 };
305 
306 static int riscv_cpu_pending_to_irq(CPURISCVState *env,
307                                     int extirq, unsigned int extirq_def_prio,
308                                     uint64_t pending, uint8_t *iprio)
309 {
310     int irq, best_irq = RISCV_EXCP_NONE;
311     unsigned int prio, best_prio = UINT_MAX;
312 
313     if (!pending) {
314         return RISCV_EXCP_NONE;
315     }
316 
317     irq = ctz64(pending);
318     if (!riscv_feature(env, RISCV_FEATURE_AIA)) {
319         return irq;
320     }
321 
322     pending = pending >> irq;
323     while (pending) {
324         prio = iprio[irq];
325         if (!prio) {
326             if (irq == extirq) {
327                 prio = extirq_def_prio;
328             } else {
329                 prio = (riscv_cpu_default_priority(irq) < extirq_def_prio) ?
330                        1 : IPRIO_MMAXIPRIO;
331             }
332         }
333         if ((pending & 0x1) && (prio <= best_prio)) {
334             best_irq = irq;
335             best_prio = prio;
336         }
337         irq++;
338         pending = pending >> 1;
339     }
340 
341     return best_irq;
342 }
343 
344 uint64_t riscv_cpu_all_pending(CPURISCVState *env)
345 {
346     uint32_t gein = get_field(env->hstatus, HSTATUS_VGEIN);
347     uint64_t vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
348 
349     return (env->mip | vsgein) & env->mie;
350 }
351 
352 int riscv_cpu_mirq_pending(CPURISCVState *env)
353 {
354     uint64_t irqs = riscv_cpu_all_pending(env) & ~env->mideleg &
355                     ~(MIP_SGEIP | MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
356 
357     return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
358                                     irqs, env->miprio);
359 }
360 
361 int riscv_cpu_sirq_pending(CPURISCVState *env)
362 {
363     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
364                     ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
365 
366     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
367                                     irqs, env->siprio);
368 }
369 
370 int riscv_cpu_vsirq_pending(CPURISCVState *env)
371 {
372     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
373                     (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
374 
375     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
376                                     irqs >> 1, env->hviprio);
377 }
378 
379 static int riscv_cpu_local_irq_pending(CPURISCVState *env)
380 {
381     int virq;
382     uint64_t irqs, pending, mie, hsie, vsie;
383 
384     /* Determine interrupt enable state of all privilege modes */
385     if (riscv_cpu_virt_enabled(env)) {
386         mie = 1;
387         hsie = 1;
388         vsie = (env->priv < PRV_S) ||
389                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
390     } else {
391         mie = (env->priv < PRV_M) ||
392               (env->priv == PRV_M && get_field(env->mstatus, MSTATUS_MIE));
393         hsie = (env->priv < PRV_S) ||
394                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
395         vsie = 0;
396     }
397 
398     /* Determine all pending interrupts */
399     pending = riscv_cpu_all_pending(env);
400 
401     /* Check M-mode interrupts */
402     irqs = pending & ~env->mideleg & -mie;
403     if (irqs) {
404         return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
405                                         irqs, env->miprio);
406     }
407 
408     /* Check HS-mode interrupts */
409     irqs = pending & env->mideleg & ~env->hideleg & -hsie;
410     if (irqs) {
411         return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
412                                         irqs, env->siprio);
413     }
414 
415     /* Check VS-mode interrupts */
416     irqs = pending & env->mideleg & env->hideleg & -vsie;
417     if (irqs) {
418         virq = riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
419                                         irqs >> 1, env->hviprio);
420         return (virq <= 0) ? virq : virq + 1;
421     }
422 
423     /* Indicate no pending interrupt */
424     return RISCV_EXCP_NONE;
425 }
426 
427 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
428 {
429     if (interrupt_request & CPU_INTERRUPT_HARD) {
430         RISCVCPU *cpu = RISCV_CPU(cs);
431         CPURISCVState *env = &cpu->env;
432         int interruptno = riscv_cpu_local_irq_pending(env);
433         if (interruptno >= 0) {
434             cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno;
435             riscv_cpu_do_interrupt(cs);
436             return true;
437         }
438     }
439     return false;
440 }
441 
442 /* Return true is floating point support is currently enabled */
443 bool riscv_cpu_fp_enabled(CPURISCVState *env)
444 {
445     if (env->mstatus & MSTATUS_FS) {
446         if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) {
447             return false;
448         }
449         return true;
450     }
451 
452     return false;
453 }
454 
455 /* Return true is vector support is currently enabled */
456 bool riscv_cpu_vector_enabled(CPURISCVState *env)
457 {
458     if (env->mstatus & MSTATUS_VS) {
459         if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) {
460             return false;
461         }
462         return true;
463     }
464 
465     return false;
466 }
467 
468 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
469 {
470     uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM |
471                             MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
472                             MSTATUS64_UXL | MSTATUS_VS;
473 
474     if (riscv_has_ext(env, RVF)) {
475         mstatus_mask |= MSTATUS_FS;
476     }
477     bool current_virt = riscv_cpu_virt_enabled(env);
478 
479     g_assert(riscv_has_ext(env, RVH));
480 
481     if (current_virt) {
482         /* Current V=1 and we are about to change to V=0 */
483         env->vsstatus = env->mstatus & mstatus_mask;
484         env->mstatus &= ~mstatus_mask;
485         env->mstatus |= env->mstatus_hs;
486 
487         env->vstvec = env->stvec;
488         env->stvec = env->stvec_hs;
489 
490         env->vsscratch = env->sscratch;
491         env->sscratch = env->sscratch_hs;
492 
493         env->vsepc = env->sepc;
494         env->sepc = env->sepc_hs;
495 
496         env->vscause = env->scause;
497         env->scause = env->scause_hs;
498 
499         env->vstval = env->stval;
500         env->stval = env->stval_hs;
501 
502         env->vsatp = env->satp;
503         env->satp = env->satp_hs;
504     } else {
505         /* Current V=0 and we are about to change to V=1 */
506         env->mstatus_hs = env->mstatus & mstatus_mask;
507         env->mstatus &= ~mstatus_mask;
508         env->mstatus |= env->vsstatus;
509 
510         env->stvec_hs = env->stvec;
511         env->stvec = env->vstvec;
512 
513         env->sscratch_hs = env->sscratch;
514         env->sscratch = env->vsscratch;
515 
516         env->sepc_hs = env->sepc;
517         env->sepc = env->vsepc;
518 
519         env->scause_hs = env->scause;
520         env->scause = env->vscause;
521 
522         env->stval_hs = env->stval;
523         env->stval = env->vstval;
524 
525         env->satp_hs = env->satp;
526         env->satp = env->vsatp;
527     }
528 }
529 
530 target_ulong riscv_cpu_get_geilen(CPURISCVState *env)
531 {
532     if (!riscv_has_ext(env, RVH)) {
533         return 0;
534     }
535 
536     return env->geilen;
537 }
538 
539 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen)
540 {
541     if (!riscv_has_ext(env, RVH)) {
542         return;
543     }
544 
545     if (geilen > (TARGET_LONG_BITS - 1)) {
546         return;
547     }
548 
549     env->geilen = geilen;
550 }
551 
552 bool riscv_cpu_virt_enabled(CPURISCVState *env)
553 {
554     if (!riscv_has_ext(env, RVH)) {
555         return false;
556     }
557 
558     return get_field(env->virt, VIRT_ONOFF);
559 }
560 
561 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
562 {
563     if (!riscv_has_ext(env, RVH)) {
564         return;
565     }
566 
567     /* Flush the TLB on all virt mode changes. */
568     if (get_field(env->virt, VIRT_ONOFF) != enable) {
569         tlb_flush(env_cpu(env));
570     }
571 
572     env->virt = set_field(env->virt, VIRT_ONOFF, enable);
573 
574     if (enable) {
575         /*
576          * The guest external interrupts from an interrupt controller are
577          * delivered only when the Guest/VM is running (i.e. V=1). This means
578          * any guest external interrupt which is triggered while the Guest/VM
579          * is not running (i.e. V=0) will be missed on QEMU resulting in guest
580          * with sluggish response to serial console input and other I/O events.
581          *
582          * To solve this, we check and inject interrupt after setting V=1.
583          */
584         riscv_cpu_update_mip(env_archcpu(env), 0, 0);
585     }
586 }
587 
588 bool riscv_cpu_two_stage_lookup(int mmu_idx)
589 {
590     return mmu_idx & TB_FLAGS_PRIV_HYP_ACCESS_MASK;
591 }
592 
593 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts)
594 {
595     CPURISCVState *env = &cpu->env;
596     if (env->miclaim & interrupts) {
597         return -1;
598     } else {
599         env->miclaim |= interrupts;
600         return 0;
601     }
602 }
603 
604 uint64_t riscv_cpu_update_mip(RISCVCPU *cpu, uint64_t mask, uint64_t value)
605 {
606     CPURISCVState *env = &cpu->env;
607     CPUState *cs = CPU(cpu);
608     uint64_t gein, vsgein = 0, old = env->mip;
609     bool locked = false;
610 
611     if (riscv_cpu_virt_enabled(env)) {
612         gein = get_field(env->hstatus, HSTATUS_VGEIN);
613         vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
614     }
615 
616     if (!qemu_mutex_iothread_locked()) {
617         locked = true;
618         qemu_mutex_lock_iothread();
619     }
620 
621     env->mip = (env->mip & ~mask) | (value & mask);
622 
623     if (env->mip | vsgein) {
624         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
625     } else {
626         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
627     }
628 
629     if (locked) {
630         qemu_mutex_unlock_iothread();
631     }
632 
633     return old;
634 }
635 
636 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void *),
637                              void *arg)
638 {
639     env->rdtime_fn = fn;
640     env->rdtime_fn_arg = arg;
641 }
642 
643 void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv,
644                                    int (*rmw_fn)(void *arg,
645                                                  target_ulong reg,
646                                                  target_ulong *val,
647                                                  target_ulong new_val,
648                                                  target_ulong write_mask),
649                                    void *rmw_fn_arg)
650 {
651     if (priv <= PRV_M) {
652         env->aia_ireg_rmw_fn[priv] = rmw_fn;
653         env->aia_ireg_rmw_fn_arg[priv] = rmw_fn_arg;
654     }
655 }
656 
657 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv)
658 {
659     if (newpriv > PRV_M) {
660         g_assert_not_reached();
661     }
662     if (newpriv == PRV_H) {
663         newpriv = PRV_U;
664     }
665     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
666     env->priv = newpriv;
667     env->xl = cpu_recompute_xl(env);
668     riscv_cpu_update_mask(env);
669 
670     /*
671      * Clear the load reservation - otherwise a reservation placed in one
672      * context/process can be used by another, resulting in an SC succeeding
673      * incorrectly. Version 2.2 of the ISA specification explicitly requires
674      * this behaviour, while later revisions say that the kernel "should" use
675      * an SC instruction to force the yielding of a load reservation on a
676      * preemptive context switch. As a result, do both.
677      */
678     env->load_res = -1;
679 }
680 
681 /*
682  * get_physical_address_pmp - check PMP permission for this physical address
683  *
684  * Match the PMP region and check permission for this physical address and it's
685  * TLB page. Returns 0 if the permission checking was successful
686  *
687  * @env: CPURISCVState
688  * @prot: The returned protection attributes
689  * @tlb_size: TLB page size containing addr. It could be modified after PMP
690  *            permission checking. NULL if not set TLB page for addr.
691  * @addr: The physical address to be checked permission
692  * @access_type: The type of MMU access
693  * @mode: Indicates current privilege level.
694  */
695 static int get_physical_address_pmp(CPURISCVState *env, int *prot,
696                                     target_ulong *tlb_size, hwaddr addr,
697                                     int size, MMUAccessType access_type,
698                                     int mode)
699 {
700     pmp_priv_t pmp_priv;
701     target_ulong tlb_size_pmp = 0;
702 
703     if (!riscv_feature(env, RISCV_FEATURE_PMP)) {
704         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
705         return TRANSLATE_SUCCESS;
706     }
707 
708     if (!pmp_hart_has_privs(env, addr, size, 1 << access_type, &pmp_priv,
709                             mode)) {
710         *prot = 0;
711         return TRANSLATE_PMP_FAIL;
712     }
713 
714     *prot = pmp_priv_to_page_prot(pmp_priv);
715     if (tlb_size != NULL) {
716         if (pmp_is_range_in_tlb(env, addr & ~(*tlb_size - 1), &tlb_size_pmp)) {
717             *tlb_size = tlb_size_pmp;
718         }
719     }
720 
721     return TRANSLATE_SUCCESS;
722 }
723 
724 /* get_physical_address - get the physical address for this virtual address
725  *
726  * Do a page table walk to obtain the physical address corresponding to a
727  * virtual address. Returns 0 if the translation was successful
728  *
729  * Adapted from Spike's mmu_t::translate and mmu_t::walk
730  *
731  * @env: CPURISCVState
732  * @physical: This will be set to the calculated physical address
733  * @prot: The returned protection attributes
734  * @addr: The virtual address to be translated
735  * @fault_pte_addr: If not NULL, this will be set to fault pte address
736  *                  when a error occurs on pte address translation.
737  *                  This will already be shifted to match htval.
738  * @access_type: The type of MMU access
739  * @mmu_idx: Indicates current privilege level
740  * @first_stage: Are we in first stage translation?
741  *               Second stage is used for hypervisor guest translation
742  * @two_stage: Are we going to perform two stage translation
743  * @is_debug: Is this access from a debugger or the monitor?
744  */
745 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
746                                 int *prot, target_ulong addr,
747                                 target_ulong *fault_pte_addr,
748                                 int access_type, int mmu_idx,
749                                 bool first_stage, bool two_stage,
750                                 bool is_debug)
751 {
752     /* NOTE: the env->pc value visible here will not be
753      * correct, but the value visible to the exception handler
754      * (riscv_cpu_do_interrupt) is correct */
755     MemTxResult res;
756     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
757     int mode = mmu_idx & TB_FLAGS_PRIV_MMU_MASK;
758     bool use_background = false;
759     hwaddr ppn;
760     RISCVCPU *cpu = env_archcpu(env);
761     int napot_bits = 0;
762     target_ulong napot_mask;
763 
764     /*
765      * Check if we should use the background registers for the two
766      * stage translation. We don't need to check if we actually need
767      * two stage translation as that happened before this function
768      * was called. Background registers will be used if the guest has
769      * forced a two stage translation to be on (in HS or M mode).
770      */
771     if (!riscv_cpu_virt_enabled(env) && two_stage) {
772         use_background = true;
773     }
774 
775     /* MPRV does not affect the virtual-machine load/store
776        instructions, HLV, HLVX, and HSV. */
777     if (riscv_cpu_two_stage_lookup(mmu_idx)) {
778         mode = get_field(env->hstatus, HSTATUS_SPVP);
779     } else if (mode == PRV_M && access_type != MMU_INST_FETCH) {
780         if (get_field(env->mstatus, MSTATUS_MPRV)) {
781             mode = get_field(env->mstatus, MSTATUS_MPP);
782         }
783     }
784 
785     if (first_stage == false) {
786         /* We are in stage 2 translation, this is similar to stage 1. */
787         /* Stage 2 is always taken as U-mode */
788         mode = PRV_U;
789     }
790 
791     if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) {
792         *physical = addr;
793         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
794         return TRANSLATE_SUCCESS;
795     }
796 
797     *prot = 0;
798 
799     hwaddr base;
800     int levels, ptidxbits, ptesize, vm, sum, mxr, widened;
801 
802     if (first_stage == true) {
803         mxr = get_field(env->mstatus, MSTATUS_MXR);
804     } else {
805         mxr = get_field(env->vsstatus, MSTATUS_MXR);
806     }
807 
808     if (first_stage == true) {
809         if (use_background) {
810             if (riscv_cpu_mxl(env) == MXL_RV32) {
811                 base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT;
812                 vm = get_field(env->vsatp, SATP32_MODE);
813             } else {
814                 base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT;
815                 vm = get_field(env->vsatp, SATP64_MODE);
816             }
817         } else {
818             if (riscv_cpu_mxl(env) == MXL_RV32) {
819                 base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT;
820                 vm = get_field(env->satp, SATP32_MODE);
821             } else {
822                 base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT;
823                 vm = get_field(env->satp, SATP64_MODE);
824             }
825         }
826         widened = 0;
827     } else {
828         if (riscv_cpu_mxl(env) == MXL_RV32) {
829             base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT;
830             vm = get_field(env->hgatp, SATP32_MODE);
831         } else {
832             base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT;
833             vm = get_field(env->hgatp, SATP64_MODE);
834         }
835         widened = 2;
836     }
837     /* status.SUM will be ignored if execute on background */
838     sum = get_field(env->mstatus, MSTATUS_SUM) || use_background || is_debug;
839     switch (vm) {
840     case VM_1_10_SV32:
841       levels = 2; ptidxbits = 10; ptesize = 4; break;
842     case VM_1_10_SV39:
843       levels = 3; ptidxbits = 9; ptesize = 8; break;
844     case VM_1_10_SV48:
845       levels = 4; ptidxbits = 9; ptesize = 8; break;
846     case VM_1_10_SV57:
847       levels = 5; ptidxbits = 9; ptesize = 8; break;
848     case VM_1_10_MBARE:
849         *physical = addr;
850         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
851         return TRANSLATE_SUCCESS;
852     default:
853       g_assert_not_reached();
854     }
855 
856     CPUState *cs = env_cpu(env);
857     int va_bits = PGSHIFT + levels * ptidxbits + widened;
858     target_ulong mask, masked_msbs;
859 
860     if (TARGET_LONG_BITS > (va_bits - 1)) {
861         mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1;
862     } else {
863         mask = 0;
864     }
865     masked_msbs = (addr >> (va_bits - 1)) & mask;
866 
867     if (masked_msbs != 0 && masked_msbs != mask) {
868         return TRANSLATE_FAIL;
869     }
870 
871     int ptshift = (levels - 1) * ptidxbits;
872     int i;
873 
874 #if !TCG_OVERSIZED_GUEST
875 restart:
876 #endif
877     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
878         target_ulong idx;
879         if (i == 0) {
880             idx = (addr >> (PGSHIFT + ptshift)) &
881                            ((1 << (ptidxbits + widened)) - 1);
882         } else {
883             idx = (addr >> (PGSHIFT + ptshift)) &
884                            ((1 << ptidxbits) - 1);
885         }
886 
887         /* check that physical address of PTE is legal */
888         hwaddr pte_addr;
889 
890         if (two_stage && first_stage) {
891             int vbase_prot;
892             hwaddr vbase;
893 
894             /* Do the second stage translation on the base PTE address. */
895             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
896                                                  base, NULL, MMU_DATA_LOAD,
897                                                  mmu_idx, false, true,
898                                                  is_debug);
899 
900             if (vbase_ret != TRANSLATE_SUCCESS) {
901                 if (fault_pte_addr) {
902                     *fault_pte_addr = (base + idx * ptesize) >> 2;
903                 }
904                 return TRANSLATE_G_STAGE_FAIL;
905             }
906 
907             pte_addr = vbase + idx * ptesize;
908         } else {
909             pte_addr = base + idx * ptesize;
910         }
911 
912         int pmp_prot;
913         int pmp_ret = get_physical_address_pmp(env, &pmp_prot, NULL, pte_addr,
914                                                sizeof(target_ulong),
915                                                MMU_DATA_LOAD, PRV_S);
916         if (pmp_ret != TRANSLATE_SUCCESS) {
917             return TRANSLATE_PMP_FAIL;
918         }
919 
920         target_ulong pte;
921         if (riscv_cpu_mxl(env) == MXL_RV32) {
922             pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
923         } else {
924             pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
925         }
926 
927         if (res != MEMTX_OK) {
928             return TRANSLATE_FAIL;
929         }
930 
931         if (riscv_cpu_sxl(env) == MXL_RV32) {
932             ppn = pte >> PTE_PPN_SHIFT;
933         } else if (cpu->cfg.ext_svpbmt || cpu->cfg.ext_svnapot) {
934             ppn = (pte & (target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT;
935         } else {
936             ppn = pte >> PTE_PPN_SHIFT;
937             if ((pte & ~(target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT) {
938                 return TRANSLATE_FAIL;
939             }
940         }
941 
942         if (!(pte & PTE_V)) {
943             /* Invalid PTE */
944             return TRANSLATE_FAIL;
945         } else if (!cpu->cfg.ext_svpbmt && (pte & PTE_PBMT)) {
946             return TRANSLATE_FAIL;
947         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
948             /* Inner PTE, continue walking */
949             if (pte & (PTE_D | PTE_A | PTE_U | PTE_ATTR)) {
950                 return TRANSLATE_FAIL;
951             }
952             base = ppn << PGSHIFT;
953         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
954             /* Reserved leaf PTE flags: PTE_W */
955             return TRANSLATE_FAIL;
956         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
957             /* Reserved leaf PTE flags: PTE_W + PTE_X */
958             return TRANSLATE_FAIL;
959         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
960                    (!sum || access_type == MMU_INST_FETCH))) {
961             /* User PTE flags when not U mode and mstatus.SUM is not set,
962                or the access type is an instruction fetch */
963             return TRANSLATE_FAIL;
964         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
965             /* Supervisor PTE flags when not S mode */
966             return TRANSLATE_FAIL;
967         } else if (ppn & ((1ULL << ptshift) - 1)) {
968             /* Misaligned PPN */
969             return TRANSLATE_FAIL;
970         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
971                    ((pte & PTE_X) && mxr))) {
972             /* Read access check failed */
973             return TRANSLATE_FAIL;
974         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
975             /* Write access check failed */
976             return TRANSLATE_FAIL;
977         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
978             /* Fetch access check failed */
979             return TRANSLATE_FAIL;
980         } else {
981             /* if necessary, set accessed and dirty bits. */
982             target_ulong updated_pte = pte | PTE_A |
983                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
984 
985             /* Page table updates need to be atomic with MTTCG enabled */
986             if (updated_pte != pte) {
987                 /*
988                  * - if accessed or dirty bits need updating, and the PTE is
989                  *   in RAM, then we do so atomically with a compare and swap.
990                  * - if the PTE is in IO space or ROM, then it can't be updated
991                  *   and we return TRANSLATE_FAIL.
992                  * - if the PTE changed by the time we went to update it, then
993                  *   it is no longer valid and we must re-walk the page table.
994                  */
995                 MemoryRegion *mr;
996                 hwaddr l = sizeof(target_ulong), addr1;
997                 mr = address_space_translate(cs->as, pte_addr,
998                     &addr1, &l, false, MEMTXATTRS_UNSPECIFIED);
999                 if (memory_region_is_ram(mr)) {
1000                     target_ulong *pte_pa =
1001                         qemu_map_ram_ptr(mr->ram_block, addr1);
1002 #if TCG_OVERSIZED_GUEST
1003                     /* MTTCG is not enabled on oversized TCG guests so
1004                      * page table updates do not need to be atomic */
1005                     *pte_pa = pte = updated_pte;
1006 #else
1007                     target_ulong old_pte =
1008                         qatomic_cmpxchg(pte_pa, pte, updated_pte);
1009                     if (old_pte != pte) {
1010                         goto restart;
1011                     } else {
1012                         pte = updated_pte;
1013                     }
1014 #endif
1015                 } else {
1016                     /* misconfigured PTE in ROM (AD bits are not preset) or
1017                      * PTE is in IO space and can't be updated atomically */
1018                     return TRANSLATE_FAIL;
1019                 }
1020             }
1021 
1022             /* for superpage mappings, make a fake leaf PTE for the TLB's
1023                benefit. */
1024             target_ulong vpn = addr >> PGSHIFT;
1025 
1026             if (cpu->cfg.ext_svnapot && (pte & PTE_N)) {
1027                 napot_bits = ctzl(ppn) + 1;
1028                 if ((i != (levels - 1)) || (napot_bits != 4)) {
1029                     return TRANSLATE_FAIL;
1030                 }
1031             }
1032 
1033             napot_mask = (1 << napot_bits) - 1;
1034             *physical = (((ppn & ~napot_mask) | (vpn & napot_mask) |
1035                           (vpn & (((target_ulong)1 << ptshift) - 1))
1036                          ) << PGSHIFT) | (addr & ~TARGET_PAGE_MASK);
1037 
1038             /* set permissions on the TLB entry */
1039             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
1040                 *prot |= PAGE_READ;
1041             }
1042             if ((pte & PTE_X)) {
1043                 *prot |= PAGE_EXEC;
1044             }
1045             /* add write permission on stores or if the page is already dirty,
1046                so that we TLB miss on later writes to update the dirty bit */
1047             if ((pte & PTE_W) &&
1048                     (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
1049                 *prot |= PAGE_WRITE;
1050             }
1051             return TRANSLATE_SUCCESS;
1052         }
1053     }
1054     return TRANSLATE_FAIL;
1055 }
1056 
1057 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
1058                                 MMUAccessType access_type, bool pmp_violation,
1059                                 bool first_stage, bool two_stage,
1060                                 bool two_stage_indirect)
1061 {
1062     CPUState *cs = env_cpu(env);
1063     int page_fault_exceptions, vm;
1064     uint64_t stap_mode;
1065 
1066     if (riscv_cpu_mxl(env) == MXL_RV32) {
1067         stap_mode = SATP32_MODE;
1068     } else {
1069         stap_mode = SATP64_MODE;
1070     }
1071 
1072     if (first_stage) {
1073         vm = get_field(env->satp, stap_mode);
1074     } else {
1075         vm = get_field(env->hgatp, stap_mode);
1076     }
1077 
1078     page_fault_exceptions = vm != VM_1_10_MBARE && !pmp_violation;
1079 
1080     switch (access_type) {
1081     case MMU_INST_FETCH:
1082         if (riscv_cpu_virt_enabled(env) && !first_stage) {
1083             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
1084         } else {
1085             cs->exception_index = page_fault_exceptions ?
1086                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
1087         }
1088         break;
1089     case MMU_DATA_LOAD:
1090         if (two_stage && !first_stage) {
1091             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
1092         } else {
1093             cs->exception_index = page_fault_exceptions ?
1094                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
1095         }
1096         break;
1097     case MMU_DATA_STORE:
1098         if (two_stage && !first_stage) {
1099             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
1100         } else {
1101             cs->exception_index = page_fault_exceptions ?
1102                 RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1103         }
1104         break;
1105     default:
1106         g_assert_not_reached();
1107     }
1108     env->badaddr = address;
1109     env->two_stage_lookup = two_stage;
1110     env->two_stage_indirect_lookup = two_stage_indirect;
1111 }
1112 
1113 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
1114 {
1115     RISCVCPU *cpu = RISCV_CPU(cs);
1116     CPURISCVState *env = &cpu->env;
1117     hwaddr phys_addr;
1118     int prot;
1119     int mmu_idx = cpu_mmu_index(&cpu->env, false);
1120 
1121     if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx,
1122                              true, riscv_cpu_virt_enabled(env), true)) {
1123         return -1;
1124     }
1125 
1126     if (riscv_cpu_virt_enabled(env)) {
1127         if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL,
1128                                  0, mmu_idx, false, true, true)) {
1129             return -1;
1130         }
1131     }
1132 
1133     return phys_addr & TARGET_PAGE_MASK;
1134 }
1135 
1136 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
1137                                      vaddr addr, unsigned size,
1138                                      MMUAccessType access_type,
1139                                      int mmu_idx, MemTxAttrs attrs,
1140                                      MemTxResult response, uintptr_t retaddr)
1141 {
1142     RISCVCPU *cpu = RISCV_CPU(cs);
1143     CPURISCVState *env = &cpu->env;
1144 
1145     if (access_type == MMU_DATA_STORE) {
1146         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1147     } else if (access_type == MMU_DATA_LOAD) {
1148         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
1149     } else {
1150         cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT;
1151     }
1152 
1153     env->badaddr = addr;
1154     env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
1155                             riscv_cpu_two_stage_lookup(mmu_idx);
1156     env->two_stage_indirect_lookup = false;
1157     cpu_loop_exit_restore(cs, retaddr);
1158 }
1159 
1160 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
1161                                    MMUAccessType access_type, int mmu_idx,
1162                                    uintptr_t retaddr)
1163 {
1164     RISCVCPU *cpu = RISCV_CPU(cs);
1165     CPURISCVState *env = &cpu->env;
1166     switch (access_type) {
1167     case MMU_INST_FETCH:
1168         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
1169         break;
1170     case MMU_DATA_LOAD:
1171         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
1172         break;
1173     case MMU_DATA_STORE:
1174         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
1175         break;
1176     default:
1177         g_assert_not_reached();
1178     }
1179     env->badaddr = addr;
1180     env->two_stage_lookup = riscv_cpu_virt_enabled(env) ||
1181                             riscv_cpu_two_stage_lookup(mmu_idx);
1182     env->two_stage_indirect_lookup = false;
1183     cpu_loop_exit_restore(cs, retaddr);
1184 }
1185 
1186 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
1187                         MMUAccessType access_type, int mmu_idx,
1188                         bool probe, uintptr_t retaddr)
1189 {
1190     RISCVCPU *cpu = RISCV_CPU(cs);
1191     CPURISCVState *env = &cpu->env;
1192     vaddr im_address;
1193     hwaddr pa = 0;
1194     int prot, prot2, prot_pmp;
1195     bool pmp_violation = false;
1196     bool first_stage_error = true;
1197     bool two_stage_lookup = false;
1198     bool two_stage_indirect_error = false;
1199     int ret = TRANSLATE_FAIL;
1200     int mode = mmu_idx;
1201     /* default TLB page size */
1202     target_ulong tlb_size = TARGET_PAGE_SIZE;
1203 
1204     env->guest_phys_fault_addr = 0;
1205 
1206     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
1207                   __func__, address, access_type, mmu_idx);
1208 
1209     /* MPRV does not affect the virtual-machine load/store
1210        instructions, HLV, HLVX, and HSV. */
1211     if (riscv_cpu_two_stage_lookup(mmu_idx)) {
1212         mode = get_field(env->hstatus, HSTATUS_SPVP);
1213     } else if (mode == PRV_M && access_type != MMU_INST_FETCH &&
1214                get_field(env->mstatus, MSTATUS_MPRV)) {
1215         mode = get_field(env->mstatus, MSTATUS_MPP);
1216         if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) {
1217             two_stage_lookup = true;
1218         }
1219     }
1220 
1221     if (riscv_cpu_virt_enabled(env) ||
1222         ((riscv_cpu_two_stage_lookup(mmu_idx) || two_stage_lookup) &&
1223          access_type != MMU_INST_FETCH)) {
1224         /* Two stage lookup */
1225         ret = get_physical_address(env, &pa, &prot, address,
1226                                    &env->guest_phys_fault_addr, access_type,
1227                                    mmu_idx, true, true, false);
1228 
1229         /*
1230          * A G-stage exception may be triggered during two state lookup.
1231          * And the env->guest_phys_fault_addr has already been set in
1232          * get_physical_address().
1233          */
1234         if (ret == TRANSLATE_G_STAGE_FAIL) {
1235             first_stage_error = false;
1236             two_stage_indirect_error = true;
1237             access_type = MMU_DATA_LOAD;
1238         }
1239 
1240         qemu_log_mask(CPU_LOG_MMU,
1241                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
1242                       TARGET_FMT_plx " prot %d\n",
1243                       __func__, address, ret, pa, prot);
1244 
1245         if (ret == TRANSLATE_SUCCESS) {
1246             /* Second stage lookup */
1247             im_address = pa;
1248 
1249             ret = get_physical_address(env, &pa, &prot2, im_address, NULL,
1250                                        access_type, mmu_idx, false, true,
1251                                        false);
1252 
1253             qemu_log_mask(CPU_LOG_MMU,
1254                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
1255                     TARGET_FMT_plx " prot %d\n",
1256                     __func__, im_address, ret, pa, prot2);
1257 
1258             prot &= prot2;
1259 
1260             if (ret == TRANSLATE_SUCCESS) {
1261                 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1262                                                size, access_type, mode);
1263 
1264                 qemu_log_mask(CPU_LOG_MMU,
1265                               "%s PMP address=" TARGET_FMT_plx " ret %d prot"
1266                               " %d tlb_size " TARGET_FMT_lu "\n",
1267                               __func__, pa, ret, prot_pmp, tlb_size);
1268 
1269                 prot &= prot_pmp;
1270             }
1271 
1272             if (ret != TRANSLATE_SUCCESS) {
1273                 /*
1274                  * Guest physical address translation failed, this is a HS
1275                  * level exception
1276                  */
1277                 first_stage_error = false;
1278                 env->guest_phys_fault_addr = (im_address |
1279                                               (address &
1280                                                (TARGET_PAGE_SIZE - 1))) >> 2;
1281             }
1282         }
1283     } else {
1284         /* Single stage lookup */
1285         ret = get_physical_address(env, &pa, &prot, address, NULL,
1286                                    access_type, mmu_idx, true, false, false);
1287 
1288         qemu_log_mask(CPU_LOG_MMU,
1289                       "%s address=%" VADDR_PRIx " ret %d physical "
1290                       TARGET_FMT_plx " prot %d\n",
1291                       __func__, address, ret, pa, prot);
1292 
1293         if (ret == TRANSLATE_SUCCESS) {
1294             ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1295                                            size, access_type, mode);
1296 
1297             qemu_log_mask(CPU_LOG_MMU,
1298                           "%s PMP address=" TARGET_FMT_plx " ret %d prot"
1299                           " %d tlb_size " TARGET_FMT_lu "\n",
1300                           __func__, pa, ret, prot_pmp, tlb_size);
1301 
1302             prot &= prot_pmp;
1303         }
1304     }
1305 
1306     if (ret == TRANSLATE_PMP_FAIL) {
1307         pmp_violation = true;
1308     }
1309 
1310     if (ret == TRANSLATE_SUCCESS) {
1311         tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
1312                      prot, mmu_idx, tlb_size);
1313         return true;
1314     } else if (probe) {
1315         return false;
1316     } else {
1317         raise_mmu_exception(env, address, access_type, pmp_violation,
1318                             first_stage_error,
1319                             riscv_cpu_virt_enabled(env) ||
1320                                 riscv_cpu_two_stage_lookup(mmu_idx),
1321                             two_stage_indirect_error);
1322         cpu_loop_exit_restore(cs, retaddr);
1323     }
1324 
1325     return true;
1326 }
1327 
1328 static target_ulong riscv_transformed_insn(CPURISCVState *env,
1329                                            target_ulong insn,
1330                                            target_ulong taddr)
1331 {
1332     target_ulong xinsn = 0;
1333     target_ulong access_rs1 = 0, access_imm = 0, access_size = 0;
1334 
1335     /*
1336      * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
1337      * be uncompressed. The Quadrant 1 of RVC instruction space need
1338      * not be transformed because these instructions won't generate
1339      * any load/store trap.
1340      */
1341 
1342     if ((insn & 0x3) != 0x3) {
1343         /* Transform 16bit instruction into 32bit instruction */
1344         switch (GET_C_OP(insn)) {
1345         case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
1346             switch (GET_C_FUNC(insn)) {
1347             case OPC_RISC_C_FUNC_FLD_LQ:
1348                 if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
1349                     xinsn = OPC_RISC_FLD;
1350                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1351                     access_rs1 = GET_C_RS1S(insn);
1352                     access_imm = GET_C_LD_IMM(insn);
1353                     access_size = 8;
1354                 }
1355                 break;
1356             case OPC_RISC_C_FUNC_LW: /* C.LW */
1357                 xinsn = OPC_RISC_LW;
1358                 xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1359                 access_rs1 = GET_C_RS1S(insn);
1360                 access_imm = GET_C_LW_IMM(insn);
1361                 access_size = 4;
1362                 break;
1363             case OPC_RISC_C_FUNC_FLW_LD:
1364                 if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
1365                     xinsn = OPC_RISC_FLW;
1366                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1367                     access_rs1 = GET_C_RS1S(insn);
1368                     access_imm = GET_C_LW_IMM(insn);
1369                     access_size = 4;
1370                 } else { /* C.LD (RV64/RV128) */
1371                     xinsn = OPC_RISC_LD;
1372                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1373                     access_rs1 = GET_C_RS1S(insn);
1374                     access_imm = GET_C_LD_IMM(insn);
1375                     access_size = 8;
1376                 }
1377                 break;
1378             case OPC_RISC_C_FUNC_FSD_SQ:
1379                 if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
1380                     xinsn = OPC_RISC_FSD;
1381                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1382                     access_rs1 = GET_C_RS1S(insn);
1383                     access_imm = GET_C_SD_IMM(insn);
1384                     access_size = 8;
1385                 }
1386                 break;
1387             case OPC_RISC_C_FUNC_SW: /* C.SW */
1388                 xinsn = OPC_RISC_SW;
1389                 xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1390                 access_rs1 = GET_C_RS1S(insn);
1391                 access_imm = GET_C_SW_IMM(insn);
1392                 access_size = 4;
1393                 break;
1394             case OPC_RISC_C_FUNC_FSW_SD:
1395                 if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
1396                     xinsn = OPC_RISC_FSW;
1397                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1398                     access_rs1 = GET_C_RS1S(insn);
1399                     access_imm = GET_C_SW_IMM(insn);
1400                     access_size = 4;
1401                 } else { /* C.SD (RV64/RV128) */
1402                     xinsn = OPC_RISC_SD;
1403                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1404                     access_rs1 = GET_C_RS1S(insn);
1405                     access_imm = GET_C_SD_IMM(insn);
1406                     access_size = 8;
1407                 }
1408                 break;
1409             default:
1410                 break;
1411             }
1412             break;
1413         case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
1414             switch (GET_C_FUNC(insn)) {
1415             case OPC_RISC_C_FUNC_FLDSP_LQSP:
1416                 if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
1417                     xinsn = OPC_RISC_FLD;
1418                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1419                     access_rs1 = 2;
1420                     access_imm = GET_C_LDSP_IMM(insn);
1421                     access_size = 8;
1422                 }
1423                 break;
1424             case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
1425                 xinsn = OPC_RISC_LW;
1426                 xinsn = SET_RD(xinsn, GET_C_RD(insn));
1427                 access_rs1 = 2;
1428                 access_imm = GET_C_LWSP_IMM(insn);
1429                 access_size = 4;
1430                 break;
1431             case OPC_RISC_C_FUNC_FLWSP_LDSP:
1432                 if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
1433                     xinsn = OPC_RISC_FLW;
1434                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1435                     access_rs1 = 2;
1436                     access_imm = GET_C_LWSP_IMM(insn);
1437                     access_size = 4;
1438                 } else { /* C.LDSP (RV64/RV128) */
1439                     xinsn = OPC_RISC_LD;
1440                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1441                     access_rs1 = 2;
1442                     access_imm = GET_C_LDSP_IMM(insn);
1443                     access_size = 8;
1444                 }
1445                 break;
1446             case OPC_RISC_C_FUNC_FSDSP_SQSP:
1447                 if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
1448                     xinsn = OPC_RISC_FSD;
1449                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1450                     access_rs1 = 2;
1451                     access_imm = GET_C_SDSP_IMM(insn);
1452                     access_size = 8;
1453                 }
1454                 break;
1455             case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
1456                 xinsn = OPC_RISC_SW;
1457                 xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1458                 access_rs1 = 2;
1459                 access_imm = GET_C_SWSP_IMM(insn);
1460                 access_size = 4;
1461                 break;
1462             case 7:
1463                 if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
1464                     xinsn = OPC_RISC_FSW;
1465                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1466                     access_rs1 = 2;
1467                     access_imm = GET_C_SWSP_IMM(insn);
1468                     access_size = 4;
1469                 } else { /* C.SDSP (RV64/RV128) */
1470                     xinsn = OPC_RISC_SD;
1471                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1472                     access_rs1 = 2;
1473                     access_imm = GET_C_SDSP_IMM(insn);
1474                     access_size = 8;
1475                 }
1476                 break;
1477             default:
1478                 break;
1479             }
1480             break;
1481         default:
1482             break;
1483         }
1484 
1485         /*
1486          * Clear Bit1 of transformed instruction to indicate that
1487          * original insruction was a 16bit instruction
1488          */
1489         xinsn &= ~((target_ulong)0x2);
1490     } else {
1491         /* Transform 32bit (or wider) instructions */
1492         switch (MASK_OP_MAJOR(insn)) {
1493         case OPC_RISC_ATOMIC:
1494             xinsn = insn;
1495             access_rs1 = GET_RS1(insn);
1496             access_size = 1 << GET_FUNCT3(insn);
1497             break;
1498         case OPC_RISC_LOAD:
1499         case OPC_RISC_FP_LOAD:
1500             xinsn = SET_I_IMM(insn, 0);
1501             access_rs1 = GET_RS1(insn);
1502             access_imm = GET_IMM(insn);
1503             access_size = 1 << GET_FUNCT3(insn);
1504             break;
1505         case OPC_RISC_STORE:
1506         case OPC_RISC_FP_STORE:
1507             xinsn = SET_S_IMM(insn, 0);
1508             access_rs1 = GET_RS1(insn);
1509             access_imm = GET_STORE_IMM(insn);
1510             access_size = 1 << GET_FUNCT3(insn);
1511             break;
1512         case OPC_RISC_SYSTEM:
1513             if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
1514                 xinsn = insn;
1515                 access_rs1 = GET_RS1(insn);
1516                 access_size = 1 << ((GET_FUNCT7(insn) >> 1) & 0x3);
1517                 access_size = 1 << access_size;
1518             }
1519             break;
1520         default:
1521             break;
1522         }
1523     }
1524 
1525     if (access_size) {
1526         xinsn = SET_RS1(xinsn, (taddr - (env->gpr[access_rs1] + access_imm)) &
1527                                (access_size - 1));
1528     }
1529 
1530     return xinsn;
1531 }
1532 #endif /* !CONFIG_USER_ONLY */
1533 
1534 /*
1535  * Handle Traps
1536  *
1537  * Adapted from Spike's processor_t::take_trap.
1538  *
1539  */
1540 void riscv_cpu_do_interrupt(CPUState *cs)
1541 {
1542 #if !defined(CONFIG_USER_ONLY)
1543 
1544     RISCVCPU *cpu = RISCV_CPU(cs);
1545     CPURISCVState *env = &cpu->env;
1546     bool write_gva = false;
1547     uint64_t s;
1548 
1549     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
1550      * so we mask off the MSB and separate into trap type and cause.
1551      */
1552     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
1553     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
1554     uint64_t deleg = async ? env->mideleg : env->medeleg;
1555     target_ulong tval = 0;
1556     target_ulong tinst = 0;
1557     target_ulong htval = 0;
1558     target_ulong mtval2 = 0;
1559 
1560     if  (cause == RISCV_EXCP_SEMIHOST) {
1561         if (env->priv >= PRV_S) {
1562             do_common_semihosting(cs);
1563             env->pc += 4;
1564             return;
1565         }
1566         cause = RISCV_EXCP_BREAKPOINT;
1567     }
1568 
1569     if (!async) {
1570         /* set tval to badaddr for traps with address information */
1571         switch (cause) {
1572         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
1573         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
1574         case RISCV_EXCP_LOAD_ADDR_MIS:
1575         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
1576         case RISCV_EXCP_LOAD_ACCESS_FAULT:
1577         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
1578         case RISCV_EXCP_LOAD_PAGE_FAULT:
1579         case RISCV_EXCP_STORE_PAGE_FAULT:
1580             write_gva = env->two_stage_lookup;
1581             tval = env->badaddr;
1582             if (env->two_stage_indirect_lookup) {
1583                 /*
1584                  * special pseudoinstruction for G-stage fault taken while
1585                  * doing VS-stage page table walk.
1586                  */
1587                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1588             } else {
1589                 /*
1590                  * The "Addr. Offset" field in transformed instruction is
1591                  * non-zero only for misaligned access.
1592                  */
1593                 tinst = riscv_transformed_insn(env, env->bins, tval);
1594             }
1595             break;
1596         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
1597         case RISCV_EXCP_INST_ADDR_MIS:
1598         case RISCV_EXCP_INST_ACCESS_FAULT:
1599         case RISCV_EXCP_INST_PAGE_FAULT:
1600             write_gva = env->two_stage_lookup;
1601             tval = env->badaddr;
1602             if (env->two_stage_indirect_lookup) {
1603                 /*
1604                  * special pseudoinstruction for G-stage fault taken while
1605                  * doing VS-stage page table walk.
1606                  */
1607                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1608             }
1609             break;
1610         case RISCV_EXCP_ILLEGAL_INST:
1611         case RISCV_EXCP_VIRT_INSTRUCTION_FAULT:
1612             tval = env->bins;
1613             break;
1614         default:
1615             break;
1616         }
1617         /* ecall is dispatched as one cause so translate based on mode */
1618         if (cause == RISCV_EXCP_U_ECALL) {
1619             assert(env->priv <= 3);
1620 
1621             if (env->priv == PRV_M) {
1622                 cause = RISCV_EXCP_M_ECALL;
1623             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
1624                 cause = RISCV_EXCP_VS_ECALL;
1625             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
1626                 cause = RISCV_EXCP_S_ECALL;
1627             } else if (env->priv == PRV_U) {
1628                 cause = RISCV_EXCP_U_ECALL;
1629             }
1630         }
1631     }
1632 
1633     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
1634                      riscv_cpu_get_trap_name(cause, async));
1635 
1636     qemu_log_mask(CPU_LOG_INT,
1637                   "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", "
1638                   "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n",
1639                   __func__, env->mhartid, async, cause, env->pc, tval,
1640                   riscv_cpu_get_trap_name(cause, async));
1641 
1642     if (env->priv <= PRV_S &&
1643             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
1644         /* handle the trap in S-mode */
1645         if (riscv_has_ext(env, RVH)) {
1646             uint64_t hdeleg = async ? env->hideleg : env->hedeleg;
1647 
1648             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1)) {
1649                 /* Trap to VS mode */
1650                 /*
1651                  * See if we need to adjust cause. Yes if its VS mode interrupt
1652                  * no if hypervisor has delegated one of hs mode's interrupt
1653                  */
1654                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
1655                     cause == IRQ_VS_EXT) {
1656                     cause = cause - 1;
1657                 }
1658                 write_gva = false;
1659             } else if (riscv_cpu_virt_enabled(env)) {
1660                 /* Trap into HS mode, from virt */
1661                 riscv_cpu_swap_hypervisor_regs(env);
1662                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
1663                                          env->priv);
1664                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
1665                                          riscv_cpu_virt_enabled(env));
1666 
1667 
1668                 htval = env->guest_phys_fault_addr;
1669 
1670                 riscv_cpu_set_virt_enabled(env, 0);
1671             } else {
1672                 /* Trap into HS mode */
1673                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false);
1674                 htval = env->guest_phys_fault_addr;
1675             }
1676             env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva);
1677         }
1678 
1679         s = env->mstatus;
1680         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
1681         s = set_field(s, MSTATUS_SPP, env->priv);
1682         s = set_field(s, MSTATUS_SIE, 0);
1683         env->mstatus = s;
1684         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
1685         env->sepc = env->pc;
1686         env->stval = tval;
1687         env->htval = htval;
1688         env->htinst = tinst;
1689         env->pc = (env->stvec >> 2 << 2) +
1690             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
1691         riscv_cpu_set_mode(env, PRV_S);
1692     } else {
1693         /* handle the trap in M-mode */
1694         if (riscv_has_ext(env, RVH)) {
1695             if (riscv_cpu_virt_enabled(env)) {
1696                 riscv_cpu_swap_hypervisor_regs(env);
1697             }
1698             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
1699                                      riscv_cpu_virt_enabled(env));
1700             if (riscv_cpu_virt_enabled(env) && tval) {
1701                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
1702             }
1703 
1704             mtval2 = env->guest_phys_fault_addr;
1705 
1706             /* Trapping to M mode, virt is disabled */
1707             riscv_cpu_set_virt_enabled(env, 0);
1708         }
1709 
1710         s = env->mstatus;
1711         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
1712         s = set_field(s, MSTATUS_MPP, env->priv);
1713         s = set_field(s, MSTATUS_MIE, 0);
1714         env->mstatus = s;
1715         env->mcause = cause | ~(((target_ulong)-1) >> async);
1716         env->mepc = env->pc;
1717         env->mtval = tval;
1718         env->mtval2 = mtval2;
1719         env->mtinst = tinst;
1720         env->pc = (env->mtvec >> 2 << 2) +
1721             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
1722         riscv_cpu_set_mode(env, PRV_M);
1723     }
1724 
1725     /* NOTE: it is not necessary to yield load reservations here. It is only
1726      * necessary for an SC from "another hart" to cause a load reservation
1727      * to be yielded. Refer to the memory consistency model section of the
1728      * RISC-V ISA Specification.
1729      */
1730 
1731     env->two_stage_lookup = false;
1732     env->two_stage_indirect_lookup = false;
1733 #endif
1734     cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
1735 }
1736