xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision b3eb5b86)
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 "pmu.h"
25 #include "exec/exec-all.h"
26 #include "instmap.h"
27 #include "tcg/tcg-op.h"
28 #include "trace.h"
29 #include "semihosting/common-semi.h"
30 #include "cpu_bits.h"
31 
32 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
33 {
34 #ifdef CONFIG_USER_ONLY
35     return 0;
36 #else
37     return env->priv;
38 #endif
39 }
40 
41 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
42                           target_ulong *cs_base, uint32_t *pflags)
43 {
44     CPUState *cs = env_cpu(env);
45     RISCVCPU *cpu = RISCV_CPU(cs);
46 
47     uint32_t flags = 0;
48 
49     *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc;
50     *cs_base = 0;
51 
52     if (riscv_has_ext(env, RVV) || cpu->cfg.ext_zve32f || cpu->cfg.ext_zve64f) {
53         /*
54          * If env->vl equals to VLMAX, we can use generic vector operation
55          * expanders (GVEC) to accerlate the vector operations.
56          * However, as LMUL could be a fractional number. The maximum
57          * vector size can be operated might be less than 8 bytes,
58          * which is not supported by GVEC. So we set vl_eq_vlmax flag to true
59          * only when maxsz >= 8 bytes.
60          */
61         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
62         uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW);
63         uint32_t maxsz = vlmax << sew;
64         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) &&
65                            (maxsz >= 8);
66         flags = FIELD_DP32(flags, TB_FLAGS, VILL, env->vill);
67         flags = FIELD_DP32(flags, TB_FLAGS, SEW, sew);
68         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
69                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
70         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
71         flags = FIELD_DP32(flags, TB_FLAGS, VTA,
72                     FIELD_EX64(env->vtype, VTYPE, VTA));
73         flags = FIELD_DP32(flags, TB_FLAGS, VMA,
74                     FIELD_EX64(env->vtype, VTYPE, VMA));
75     } else {
76         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
77     }
78 
79 #ifdef CONFIG_USER_ONLY
80     flags |= TB_FLAGS_MSTATUS_FS;
81     flags |= TB_FLAGS_MSTATUS_VS;
82 #else
83     flags |= cpu_mmu_index(env, 0);
84     if (riscv_cpu_fp_enabled(env)) {
85         flags |= env->mstatus & MSTATUS_FS;
86     }
87 
88     if (riscv_cpu_vector_enabled(env)) {
89         flags |= env->mstatus & MSTATUS_VS;
90     }
91 
92     if (riscv_has_ext(env, RVH)) {
93         if (env->priv == PRV_M ||
94             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
95             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
96                 get_field(env->hstatus, HSTATUS_HU))) {
97             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
98         }
99 
100         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS,
101                            get_field(env->mstatus_hs, MSTATUS_FS));
102 
103         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS,
104                            get_field(env->mstatus_hs, MSTATUS_VS));
105     }
106 #endif
107 
108     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
109     if (env->cur_pmmask < (env->xl == MXL_RV32 ? UINT32_MAX : UINT64_MAX)) {
110         flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
111     }
112     if (env->cur_pmbase != 0) {
113         flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1);
114     }
115 
116     *pflags = flags;
117 }
118 
119 void riscv_cpu_update_mask(CPURISCVState *env)
120 {
121     target_ulong mask = -1, base = 0;
122     /*
123      * TODO: Current RVJ spec does not specify
124      * how the extension interacts with XLEN.
125      */
126 #ifndef CONFIG_USER_ONLY
127     if (riscv_has_ext(env, RVJ)) {
128         switch (env->priv) {
129         case PRV_M:
130             if (env->mmte & M_PM_ENABLE) {
131                 mask = env->mpmmask;
132                 base = env->mpmbase;
133             }
134             break;
135         case PRV_S:
136             if (env->mmte & S_PM_ENABLE) {
137                 mask = env->spmmask;
138                 base = env->spmbase;
139             }
140             break;
141         case PRV_U:
142             if (env->mmte & U_PM_ENABLE) {
143                 mask = env->upmmask;
144                 base = env->upmbase;
145             }
146             break;
147         default:
148             g_assert_not_reached();
149         }
150     }
151 #endif
152     if (env->xl == MXL_RV32) {
153         env->cur_pmmask = mask & UINT32_MAX;
154         env->cur_pmbase = base & UINT32_MAX;
155     } else {
156         env->cur_pmmask = mask;
157         env->cur_pmbase = base;
158     }
159 }
160 
161 #ifndef CONFIG_USER_ONLY
162 
163 /*
164  * The HS-mode is allowed to configure priority only for the
165  * following VS-mode local interrupts:
166  *
167  * 0  (Reserved interrupt, reads as zero)
168  * 1  Supervisor software interrupt
169  * 4  (Reserved interrupt, reads as zero)
170  * 5  Supervisor timer interrupt
171  * 8  (Reserved interrupt, reads as zero)
172  * 13 (Reserved interrupt)
173  * 14 "
174  * 15 "
175  * 16 "
176  * 17 "
177  * 18 "
178  * 19 "
179  * 20 "
180  * 21 "
181  * 22 "
182  * 23 "
183  */
184 
185 static const int hviprio_index2irq[] = {
186     0, 1, 4, 5, 8, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 };
187 static const int hviprio_index2rdzero[] = {
188     1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
189 
190 int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero)
191 {
192     if (index < 0 || ARRAY_SIZE(hviprio_index2irq) <= index) {
193         return -EINVAL;
194     }
195 
196     if (out_irq) {
197         *out_irq = hviprio_index2irq[index];
198     }
199 
200     if (out_rdzero) {
201         *out_rdzero = hviprio_index2rdzero[index];
202     }
203 
204     return 0;
205 }
206 
207 /*
208  * Default priorities of local interrupts are defined in the
209  * RISC-V Advanced Interrupt Architecture specification.
210  *
211  * ----------------------------------------------------------------
212  *  Default  |
213  *  Priority | Major Interrupt Numbers
214  * ----------------------------------------------------------------
215  *  Highest  | 47, 23, 46, 45, 22, 44,
216  *           | 43, 21, 42, 41, 20, 40
217  *           |
218  *           | 11 (0b),  3 (03),  7 (07)
219  *           |  9 (09),  1 (01),  5 (05)
220  *           | 12 (0c)
221  *           | 10 (0a),  2 (02),  6 (06)
222  *           |
223  *           | 39, 19, 38, 37, 18, 36,
224  *  Lowest   | 35, 17, 34, 33, 16, 32
225  * ----------------------------------------------------------------
226  */
227 static const uint8_t default_iprio[64] = {
228  /* Custom interrupts 48 to 63 */
229  [63] = IPRIO_MMAXIPRIO,
230  [62] = IPRIO_MMAXIPRIO,
231  [61] = IPRIO_MMAXIPRIO,
232  [60] = IPRIO_MMAXIPRIO,
233  [59] = IPRIO_MMAXIPRIO,
234  [58] = IPRIO_MMAXIPRIO,
235  [57] = IPRIO_MMAXIPRIO,
236  [56] = IPRIO_MMAXIPRIO,
237  [55] = IPRIO_MMAXIPRIO,
238  [54] = IPRIO_MMAXIPRIO,
239  [53] = IPRIO_MMAXIPRIO,
240  [52] = IPRIO_MMAXIPRIO,
241  [51] = IPRIO_MMAXIPRIO,
242  [50] = IPRIO_MMAXIPRIO,
243  [49] = IPRIO_MMAXIPRIO,
244  [48] = IPRIO_MMAXIPRIO,
245 
246  /* Custom interrupts 24 to 31 */
247  [31] = IPRIO_MMAXIPRIO,
248  [30] = IPRIO_MMAXIPRIO,
249  [29] = IPRIO_MMAXIPRIO,
250  [28] = IPRIO_MMAXIPRIO,
251  [27] = IPRIO_MMAXIPRIO,
252  [26] = IPRIO_MMAXIPRIO,
253  [25] = IPRIO_MMAXIPRIO,
254  [24] = IPRIO_MMAXIPRIO,
255 
256  [47] = IPRIO_DEFAULT_UPPER,
257  [23] = IPRIO_DEFAULT_UPPER + 1,
258  [46] = IPRIO_DEFAULT_UPPER + 2,
259  [45] = IPRIO_DEFAULT_UPPER + 3,
260  [22] = IPRIO_DEFAULT_UPPER + 4,
261  [44] = IPRIO_DEFAULT_UPPER + 5,
262 
263  [43] = IPRIO_DEFAULT_UPPER + 6,
264  [21] = IPRIO_DEFAULT_UPPER + 7,
265  [42] = IPRIO_DEFAULT_UPPER + 8,
266  [41] = IPRIO_DEFAULT_UPPER + 9,
267  [20] = IPRIO_DEFAULT_UPPER + 10,
268  [40] = IPRIO_DEFAULT_UPPER + 11,
269 
270  [11] = IPRIO_DEFAULT_M,
271  [3]  = IPRIO_DEFAULT_M + 1,
272  [7]  = IPRIO_DEFAULT_M + 2,
273 
274  [9]  = IPRIO_DEFAULT_S,
275  [1]  = IPRIO_DEFAULT_S + 1,
276  [5]  = IPRIO_DEFAULT_S + 2,
277 
278  [12] = IPRIO_DEFAULT_SGEXT,
279 
280  [10] = IPRIO_DEFAULT_VS,
281  [2]  = IPRIO_DEFAULT_VS + 1,
282  [6]  = IPRIO_DEFAULT_VS + 2,
283 
284  [39] = IPRIO_DEFAULT_LOWER,
285  [19] = IPRIO_DEFAULT_LOWER + 1,
286  [38] = IPRIO_DEFAULT_LOWER + 2,
287  [37] = IPRIO_DEFAULT_LOWER + 3,
288  [18] = IPRIO_DEFAULT_LOWER + 4,
289  [36] = IPRIO_DEFAULT_LOWER + 5,
290 
291  [35] = IPRIO_DEFAULT_LOWER + 6,
292  [17] = IPRIO_DEFAULT_LOWER + 7,
293  [34] = IPRIO_DEFAULT_LOWER + 8,
294  [33] = IPRIO_DEFAULT_LOWER + 9,
295  [16] = IPRIO_DEFAULT_LOWER + 10,
296  [32] = IPRIO_DEFAULT_LOWER + 11,
297 };
298 
299 uint8_t riscv_cpu_default_priority(int irq)
300 {
301     if (irq < 0 || irq > 63) {
302         return IPRIO_MMAXIPRIO;
303     }
304 
305     return default_iprio[irq] ? default_iprio[irq] : IPRIO_MMAXIPRIO;
306 };
307 
308 static int riscv_cpu_pending_to_irq(CPURISCVState *env,
309                                     int extirq, unsigned int extirq_def_prio,
310                                     uint64_t pending, uint8_t *iprio)
311 {
312     RISCVCPU *cpu = env_archcpu(env);
313     int irq, best_irq = RISCV_EXCP_NONE;
314     unsigned int prio, best_prio = UINT_MAX;
315 
316     if (!pending) {
317         return RISCV_EXCP_NONE;
318     }
319 
320     irq = ctz64(pending);
321     if (!((extirq == IRQ_M_EXT) ? cpu->cfg.ext_smaia : cpu->cfg.ext_ssaia)) {
322         return irq;
323     }
324 
325     pending = pending >> irq;
326     while (pending) {
327         prio = iprio[irq];
328         if (!prio) {
329             if (irq == extirq) {
330                 prio = extirq_def_prio;
331             } else {
332                 prio = (riscv_cpu_default_priority(irq) < extirq_def_prio) ?
333                        1 : IPRIO_MMAXIPRIO;
334             }
335         }
336         if ((pending & 0x1) && (prio <= best_prio)) {
337             best_irq = irq;
338             best_prio = prio;
339         }
340         irq++;
341         pending = pending >> 1;
342     }
343 
344     return best_irq;
345 }
346 
347 uint64_t riscv_cpu_all_pending(CPURISCVState *env)
348 {
349     uint32_t gein = get_field(env->hstatus, HSTATUS_VGEIN);
350     uint64_t vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
351     uint64_t vstip = (env->vstime_irq) ? MIP_VSTIP : 0;
352 
353     return (env->mip | vsgein | vstip) & env->mie;
354 }
355 
356 int riscv_cpu_mirq_pending(CPURISCVState *env)
357 {
358     uint64_t irqs = riscv_cpu_all_pending(env) & ~env->mideleg &
359                     ~(MIP_SGEIP | MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
360 
361     return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
362                                     irqs, env->miprio);
363 }
364 
365 int riscv_cpu_sirq_pending(CPURISCVState *env)
366 {
367     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
368                     ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
369 
370     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
371                                     irqs, env->siprio);
372 }
373 
374 int riscv_cpu_vsirq_pending(CPURISCVState *env)
375 {
376     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
377                     (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
378 
379     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
380                                     irqs >> 1, env->hviprio);
381 }
382 
383 static int riscv_cpu_local_irq_pending(CPURISCVState *env)
384 {
385     int virq;
386     uint64_t irqs, pending, mie, hsie, vsie;
387 
388     /* Determine interrupt enable state of all privilege modes */
389     if (riscv_cpu_virt_enabled(env)) {
390         mie = 1;
391         hsie = 1;
392         vsie = (env->priv < PRV_S) ||
393                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
394     } else {
395         mie = (env->priv < PRV_M) ||
396               (env->priv == PRV_M && get_field(env->mstatus, MSTATUS_MIE));
397         hsie = (env->priv < PRV_S) ||
398                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
399         vsie = 0;
400     }
401 
402     /* Determine all pending interrupts */
403     pending = riscv_cpu_all_pending(env);
404 
405     /* Check M-mode interrupts */
406     irqs = pending & ~env->mideleg & -mie;
407     if (irqs) {
408         return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
409                                         irqs, env->miprio);
410     }
411 
412     /* Check HS-mode interrupts */
413     irqs = pending & env->mideleg & ~env->hideleg & -hsie;
414     if (irqs) {
415         return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
416                                         irqs, env->siprio);
417     }
418 
419     /* Check VS-mode interrupts */
420     irqs = pending & env->mideleg & env->hideleg & -vsie;
421     if (irqs) {
422         virq = riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
423                                         irqs >> 1, env->hviprio);
424         return (virq <= 0) ? virq : virq + 1;
425     }
426 
427     /* Indicate no pending interrupt */
428     return RISCV_EXCP_NONE;
429 }
430 
431 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
432 {
433     if (interrupt_request & CPU_INTERRUPT_HARD) {
434         RISCVCPU *cpu = RISCV_CPU(cs);
435         CPURISCVState *env = &cpu->env;
436         int interruptno = riscv_cpu_local_irq_pending(env);
437         if (interruptno >= 0) {
438             cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno;
439             riscv_cpu_do_interrupt(cs);
440             return true;
441         }
442     }
443     return false;
444 }
445 
446 /* Return true is floating point support is currently enabled */
447 bool riscv_cpu_fp_enabled(CPURISCVState *env)
448 {
449     if (env->mstatus & MSTATUS_FS) {
450         if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) {
451             return false;
452         }
453         return true;
454     }
455 
456     return false;
457 }
458 
459 /* Return true is vector support is currently enabled */
460 bool riscv_cpu_vector_enabled(CPURISCVState *env)
461 {
462     if (env->mstatus & MSTATUS_VS) {
463         if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) {
464             return false;
465         }
466         return true;
467     }
468 
469     return false;
470 }
471 
472 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
473 {
474     uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM |
475                             MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
476                             MSTATUS64_UXL | MSTATUS_VS;
477 
478     if (riscv_has_ext(env, RVF)) {
479         mstatus_mask |= MSTATUS_FS;
480     }
481     bool current_virt = riscv_cpu_virt_enabled(env);
482 
483     g_assert(riscv_has_ext(env, RVH));
484 
485     if (current_virt) {
486         /* Current V=1 and we are about to change to V=0 */
487         env->vsstatus = env->mstatus & mstatus_mask;
488         env->mstatus &= ~mstatus_mask;
489         env->mstatus |= env->mstatus_hs;
490 
491         env->vstvec = env->stvec;
492         env->stvec = env->stvec_hs;
493 
494         env->vsscratch = env->sscratch;
495         env->sscratch = env->sscratch_hs;
496 
497         env->vsepc = env->sepc;
498         env->sepc = env->sepc_hs;
499 
500         env->vscause = env->scause;
501         env->scause = env->scause_hs;
502 
503         env->vstval = env->stval;
504         env->stval = env->stval_hs;
505 
506         env->vsatp = env->satp;
507         env->satp = env->satp_hs;
508     } else {
509         /* Current V=0 and we are about to change to V=1 */
510         env->mstatus_hs = env->mstatus & mstatus_mask;
511         env->mstatus &= ~mstatus_mask;
512         env->mstatus |= env->vsstatus;
513 
514         env->stvec_hs = env->stvec;
515         env->stvec = env->vstvec;
516 
517         env->sscratch_hs = env->sscratch;
518         env->sscratch = env->vsscratch;
519 
520         env->sepc_hs = env->sepc;
521         env->sepc = env->vsepc;
522 
523         env->scause_hs = env->scause;
524         env->scause = env->vscause;
525 
526         env->stval_hs = env->stval;
527         env->stval = env->vstval;
528 
529         env->satp_hs = env->satp;
530         env->satp = env->vsatp;
531     }
532 }
533 
534 target_ulong riscv_cpu_get_geilen(CPURISCVState *env)
535 {
536     if (!riscv_has_ext(env, RVH)) {
537         return 0;
538     }
539 
540     return env->geilen;
541 }
542 
543 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen)
544 {
545     if (!riscv_has_ext(env, RVH)) {
546         return;
547     }
548 
549     if (geilen > (TARGET_LONG_BITS - 1)) {
550         return;
551     }
552 
553     env->geilen = geilen;
554 }
555 
556 bool riscv_cpu_virt_enabled(CPURISCVState *env)
557 {
558     if (!riscv_has_ext(env, RVH)) {
559         return false;
560     }
561 
562     return get_field(env->virt, VIRT_ONOFF);
563 }
564 
565 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
566 {
567     if (!riscv_has_ext(env, RVH)) {
568         return;
569     }
570 
571     /* Flush the TLB on all virt mode changes. */
572     if (get_field(env->virt, VIRT_ONOFF) != enable) {
573         tlb_flush(env_cpu(env));
574     }
575 
576     env->virt = set_field(env->virt, VIRT_ONOFF, enable);
577 
578     if (enable) {
579         /*
580          * The guest external interrupts from an interrupt controller are
581          * delivered only when the Guest/VM is running (i.e. V=1). This means
582          * any guest external interrupt which is triggered while the Guest/VM
583          * is not running (i.e. V=0) will be missed on QEMU resulting in guest
584          * with sluggish response to serial console input and other I/O events.
585          *
586          * To solve this, we check and inject interrupt after setting V=1.
587          */
588         riscv_cpu_update_mip(env_archcpu(env), 0, 0);
589     }
590 }
591 
592 bool riscv_cpu_two_stage_lookup(int mmu_idx)
593 {
594     return mmu_idx & TB_FLAGS_PRIV_HYP_ACCESS_MASK;
595 }
596 
597 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts)
598 {
599     CPURISCVState *env = &cpu->env;
600     if (env->miclaim & interrupts) {
601         return -1;
602     } else {
603         env->miclaim |= interrupts;
604         return 0;
605     }
606 }
607 
608 uint64_t riscv_cpu_update_mip(RISCVCPU *cpu, uint64_t mask, uint64_t value)
609 {
610     CPURISCVState *env = &cpu->env;
611     CPUState *cs = CPU(cpu);
612     uint64_t gein, vsgein = 0, vstip = 0, old = env->mip;
613 
614     if (riscv_cpu_virt_enabled(env)) {
615         gein = get_field(env->hstatus, HSTATUS_VGEIN);
616         vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
617     }
618 
619     /* No need to update mip for VSTIP */
620     mask = ((mask == MIP_VSTIP) && env->vstime_irq) ? 0 : mask;
621     vstip = env->vstime_irq ? MIP_VSTIP : 0;
622 
623     QEMU_IOTHREAD_LOCK_GUARD();
624 
625     env->mip = (env->mip & ~mask) | (value & mask);
626 
627     if (env->mip | vsgein | vstip) {
628         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
629     } else {
630         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
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 
1187 static void pmu_tlb_fill_incr_ctr(RISCVCPU *cpu, MMUAccessType access_type)
1188 {
1189     enum riscv_pmu_event_idx pmu_event_type;
1190 
1191     switch (access_type) {
1192     case MMU_INST_FETCH:
1193         pmu_event_type = RISCV_PMU_EVENT_CACHE_ITLB_PREFETCH_MISS;
1194         break;
1195     case MMU_DATA_LOAD:
1196         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_READ_MISS;
1197         break;
1198     case MMU_DATA_STORE:
1199         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_WRITE_MISS;
1200         break;
1201     default:
1202         return;
1203     }
1204 
1205     riscv_pmu_incr_ctr(cpu, pmu_event_type);
1206 }
1207 
1208 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
1209                         MMUAccessType access_type, int mmu_idx,
1210                         bool probe, uintptr_t retaddr)
1211 {
1212     RISCVCPU *cpu = RISCV_CPU(cs);
1213     CPURISCVState *env = &cpu->env;
1214     vaddr im_address;
1215     hwaddr pa = 0;
1216     int prot, prot2, prot_pmp;
1217     bool pmp_violation = false;
1218     bool first_stage_error = true;
1219     bool two_stage_lookup = false;
1220     bool two_stage_indirect_error = false;
1221     int ret = TRANSLATE_FAIL;
1222     int mode = mmu_idx;
1223     /* default TLB page size */
1224     target_ulong tlb_size = TARGET_PAGE_SIZE;
1225 
1226     env->guest_phys_fault_addr = 0;
1227 
1228     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
1229                   __func__, address, access_type, mmu_idx);
1230 
1231     /* MPRV does not affect the virtual-machine load/store
1232        instructions, HLV, HLVX, and HSV. */
1233     if (riscv_cpu_two_stage_lookup(mmu_idx)) {
1234         mode = get_field(env->hstatus, HSTATUS_SPVP);
1235     } else if (mode == PRV_M && access_type != MMU_INST_FETCH &&
1236                get_field(env->mstatus, MSTATUS_MPRV)) {
1237         mode = get_field(env->mstatus, MSTATUS_MPP);
1238         if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) {
1239             two_stage_lookup = true;
1240         }
1241     }
1242 
1243     if (riscv_cpu_virt_enabled(env) ||
1244         ((riscv_cpu_two_stage_lookup(mmu_idx) || two_stage_lookup) &&
1245          access_type != MMU_INST_FETCH)) {
1246         /* Two stage lookup */
1247         ret = get_physical_address(env, &pa, &prot, address,
1248                                    &env->guest_phys_fault_addr, access_type,
1249                                    mmu_idx, true, true, false);
1250 
1251         /*
1252          * A G-stage exception may be triggered during two state lookup.
1253          * And the env->guest_phys_fault_addr has already been set in
1254          * get_physical_address().
1255          */
1256         if (ret == TRANSLATE_G_STAGE_FAIL) {
1257             first_stage_error = false;
1258             two_stage_indirect_error = true;
1259             access_type = MMU_DATA_LOAD;
1260         }
1261 
1262         qemu_log_mask(CPU_LOG_MMU,
1263                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
1264                       TARGET_FMT_plx " prot %d\n",
1265                       __func__, address, ret, pa, prot);
1266 
1267         if (ret == TRANSLATE_SUCCESS) {
1268             /* Second stage lookup */
1269             im_address = pa;
1270 
1271             ret = get_physical_address(env, &pa, &prot2, im_address, NULL,
1272                                        access_type, mmu_idx, false, true,
1273                                        false);
1274 
1275             qemu_log_mask(CPU_LOG_MMU,
1276                     "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
1277                     TARGET_FMT_plx " prot %d\n",
1278                     __func__, im_address, ret, pa, prot2);
1279 
1280             prot &= prot2;
1281 
1282             if (ret == TRANSLATE_SUCCESS) {
1283                 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1284                                                size, access_type, mode);
1285 
1286                 qemu_log_mask(CPU_LOG_MMU,
1287                               "%s PMP address=" TARGET_FMT_plx " ret %d prot"
1288                               " %d tlb_size " TARGET_FMT_lu "\n",
1289                               __func__, pa, ret, prot_pmp, tlb_size);
1290 
1291                 prot &= prot_pmp;
1292             }
1293 
1294             if (ret != TRANSLATE_SUCCESS) {
1295                 /*
1296                  * Guest physical address translation failed, this is a HS
1297                  * level exception
1298                  */
1299                 first_stage_error = false;
1300                 env->guest_phys_fault_addr = (im_address |
1301                                               (address &
1302                                                (TARGET_PAGE_SIZE - 1))) >> 2;
1303             }
1304         }
1305     } else {
1306         pmu_tlb_fill_incr_ctr(cpu, access_type);
1307         /* Single stage lookup */
1308         ret = get_physical_address(env, &pa, &prot, address, NULL,
1309                                    access_type, mmu_idx, true, false, false);
1310 
1311         qemu_log_mask(CPU_LOG_MMU,
1312                       "%s address=%" VADDR_PRIx " ret %d physical "
1313                       TARGET_FMT_plx " prot %d\n",
1314                       __func__, address, ret, pa, prot);
1315 
1316         if (ret == TRANSLATE_SUCCESS) {
1317             ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1318                                            size, access_type, mode);
1319 
1320             qemu_log_mask(CPU_LOG_MMU,
1321                           "%s PMP address=" TARGET_FMT_plx " ret %d prot"
1322                           " %d tlb_size " TARGET_FMT_lu "\n",
1323                           __func__, pa, ret, prot_pmp, tlb_size);
1324 
1325             prot &= prot_pmp;
1326         }
1327     }
1328 
1329     if (ret == TRANSLATE_PMP_FAIL) {
1330         pmp_violation = true;
1331     }
1332 
1333     if (ret == TRANSLATE_SUCCESS) {
1334         tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
1335                      prot, mmu_idx, tlb_size);
1336         return true;
1337     } else if (probe) {
1338         return false;
1339     } else {
1340         raise_mmu_exception(env, address, access_type, pmp_violation,
1341                             first_stage_error,
1342                             riscv_cpu_virt_enabled(env) ||
1343                                 riscv_cpu_two_stage_lookup(mmu_idx),
1344                             two_stage_indirect_error);
1345         cpu_loop_exit_restore(cs, retaddr);
1346     }
1347 
1348     return true;
1349 }
1350 
1351 static target_ulong riscv_transformed_insn(CPURISCVState *env,
1352                                            target_ulong insn,
1353                                            target_ulong taddr)
1354 {
1355     target_ulong xinsn = 0;
1356     target_ulong access_rs1 = 0, access_imm = 0, access_size = 0;
1357 
1358     /*
1359      * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
1360      * be uncompressed. The Quadrant 1 of RVC instruction space need
1361      * not be transformed because these instructions won't generate
1362      * any load/store trap.
1363      */
1364 
1365     if ((insn & 0x3) != 0x3) {
1366         /* Transform 16bit instruction into 32bit instruction */
1367         switch (GET_C_OP(insn)) {
1368         case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
1369             switch (GET_C_FUNC(insn)) {
1370             case OPC_RISC_C_FUNC_FLD_LQ:
1371                 if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
1372                     xinsn = OPC_RISC_FLD;
1373                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1374                     access_rs1 = GET_C_RS1S(insn);
1375                     access_imm = GET_C_LD_IMM(insn);
1376                     access_size = 8;
1377                 }
1378                 break;
1379             case OPC_RISC_C_FUNC_LW: /* C.LW */
1380                 xinsn = OPC_RISC_LW;
1381                 xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1382                 access_rs1 = GET_C_RS1S(insn);
1383                 access_imm = GET_C_LW_IMM(insn);
1384                 access_size = 4;
1385                 break;
1386             case OPC_RISC_C_FUNC_FLW_LD:
1387                 if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
1388                     xinsn = OPC_RISC_FLW;
1389                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1390                     access_rs1 = GET_C_RS1S(insn);
1391                     access_imm = GET_C_LW_IMM(insn);
1392                     access_size = 4;
1393                 } else { /* C.LD (RV64/RV128) */
1394                     xinsn = OPC_RISC_LD;
1395                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1396                     access_rs1 = GET_C_RS1S(insn);
1397                     access_imm = GET_C_LD_IMM(insn);
1398                     access_size = 8;
1399                 }
1400                 break;
1401             case OPC_RISC_C_FUNC_FSD_SQ:
1402                 if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
1403                     xinsn = OPC_RISC_FSD;
1404                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1405                     access_rs1 = GET_C_RS1S(insn);
1406                     access_imm = GET_C_SD_IMM(insn);
1407                     access_size = 8;
1408                 }
1409                 break;
1410             case OPC_RISC_C_FUNC_SW: /* C.SW */
1411                 xinsn = OPC_RISC_SW;
1412                 xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1413                 access_rs1 = GET_C_RS1S(insn);
1414                 access_imm = GET_C_SW_IMM(insn);
1415                 access_size = 4;
1416                 break;
1417             case OPC_RISC_C_FUNC_FSW_SD:
1418                 if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
1419                     xinsn = OPC_RISC_FSW;
1420                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1421                     access_rs1 = GET_C_RS1S(insn);
1422                     access_imm = GET_C_SW_IMM(insn);
1423                     access_size = 4;
1424                 } else { /* C.SD (RV64/RV128) */
1425                     xinsn = OPC_RISC_SD;
1426                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1427                     access_rs1 = GET_C_RS1S(insn);
1428                     access_imm = GET_C_SD_IMM(insn);
1429                     access_size = 8;
1430                 }
1431                 break;
1432             default:
1433                 break;
1434             }
1435             break;
1436         case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
1437             switch (GET_C_FUNC(insn)) {
1438             case OPC_RISC_C_FUNC_FLDSP_LQSP:
1439                 if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
1440                     xinsn = OPC_RISC_FLD;
1441                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1442                     access_rs1 = 2;
1443                     access_imm = GET_C_LDSP_IMM(insn);
1444                     access_size = 8;
1445                 }
1446                 break;
1447             case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
1448                 xinsn = OPC_RISC_LW;
1449                 xinsn = SET_RD(xinsn, GET_C_RD(insn));
1450                 access_rs1 = 2;
1451                 access_imm = GET_C_LWSP_IMM(insn);
1452                 access_size = 4;
1453                 break;
1454             case OPC_RISC_C_FUNC_FLWSP_LDSP:
1455                 if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
1456                     xinsn = OPC_RISC_FLW;
1457                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1458                     access_rs1 = 2;
1459                     access_imm = GET_C_LWSP_IMM(insn);
1460                     access_size = 4;
1461                 } else { /* C.LDSP (RV64/RV128) */
1462                     xinsn = OPC_RISC_LD;
1463                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1464                     access_rs1 = 2;
1465                     access_imm = GET_C_LDSP_IMM(insn);
1466                     access_size = 8;
1467                 }
1468                 break;
1469             case OPC_RISC_C_FUNC_FSDSP_SQSP:
1470                 if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
1471                     xinsn = OPC_RISC_FSD;
1472                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1473                     access_rs1 = 2;
1474                     access_imm = GET_C_SDSP_IMM(insn);
1475                     access_size = 8;
1476                 }
1477                 break;
1478             case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
1479                 xinsn = OPC_RISC_SW;
1480                 xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1481                 access_rs1 = 2;
1482                 access_imm = GET_C_SWSP_IMM(insn);
1483                 access_size = 4;
1484                 break;
1485             case 7:
1486                 if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
1487                     xinsn = OPC_RISC_FSW;
1488                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1489                     access_rs1 = 2;
1490                     access_imm = GET_C_SWSP_IMM(insn);
1491                     access_size = 4;
1492                 } else { /* C.SDSP (RV64/RV128) */
1493                     xinsn = OPC_RISC_SD;
1494                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1495                     access_rs1 = 2;
1496                     access_imm = GET_C_SDSP_IMM(insn);
1497                     access_size = 8;
1498                 }
1499                 break;
1500             default:
1501                 break;
1502             }
1503             break;
1504         default:
1505             break;
1506         }
1507 
1508         /*
1509          * Clear Bit1 of transformed instruction to indicate that
1510          * original insruction was a 16bit instruction
1511          */
1512         xinsn &= ~((target_ulong)0x2);
1513     } else {
1514         /* Transform 32bit (or wider) instructions */
1515         switch (MASK_OP_MAJOR(insn)) {
1516         case OPC_RISC_ATOMIC:
1517             xinsn = insn;
1518             access_rs1 = GET_RS1(insn);
1519             access_size = 1 << GET_FUNCT3(insn);
1520             break;
1521         case OPC_RISC_LOAD:
1522         case OPC_RISC_FP_LOAD:
1523             xinsn = SET_I_IMM(insn, 0);
1524             access_rs1 = GET_RS1(insn);
1525             access_imm = GET_IMM(insn);
1526             access_size = 1 << GET_FUNCT3(insn);
1527             break;
1528         case OPC_RISC_STORE:
1529         case OPC_RISC_FP_STORE:
1530             xinsn = SET_S_IMM(insn, 0);
1531             access_rs1 = GET_RS1(insn);
1532             access_imm = GET_STORE_IMM(insn);
1533             access_size = 1 << GET_FUNCT3(insn);
1534             break;
1535         case OPC_RISC_SYSTEM:
1536             if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
1537                 xinsn = insn;
1538                 access_rs1 = GET_RS1(insn);
1539                 access_size = 1 << ((GET_FUNCT7(insn) >> 1) & 0x3);
1540                 access_size = 1 << access_size;
1541             }
1542             break;
1543         default:
1544             break;
1545         }
1546     }
1547 
1548     if (access_size) {
1549         xinsn = SET_RS1(xinsn, (taddr - (env->gpr[access_rs1] + access_imm)) &
1550                                (access_size - 1));
1551     }
1552 
1553     return xinsn;
1554 }
1555 #endif /* !CONFIG_USER_ONLY */
1556 
1557 /*
1558  * Handle Traps
1559  *
1560  * Adapted from Spike's processor_t::take_trap.
1561  *
1562  */
1563 void riscv_cpu_do_interrupt(CPUState *cs)
1564 {
1565 #if !defined(CONFIG_USER_ONLY)
1566 
1567     RISCVCPU *cpu = RISCV_CPU(cs);
1568     CPURISCVState *env = &cpu->env;
1569     bool write_gva = false;
1570     uint64_t s;
1571 
1572     /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
1573      * so we mask off the MSB and separate into trap type and cause.
1574      */
1575     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
1576     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
1577     uint64_t deleg = async ? env->mideleg : env->medeleg;
1578     target_ulong tval = 0;
1579     target_ulong tinst = 0;
1580     target_ulong htval = 0;
1581     target_ulong mtval2 = 0;
1582 
1583     if  (cause == RISCV_EXCP_SEMIHOST) {
1584         do_common_semihosting(cs);
1585         env->pc += 4;
1586         return;
1587     }
1588 
1589     if (!async) {
1590         /* set tval to badaddr for traps with address information */
1591         switch (cause) {
1592         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
1593         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
1594         case RISCV_EXCP_LOAD_ADDR_MIS:
1595         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
1596         case RISCV_EXCP_LOAD_ACCESS_FAULT:
1597         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
1598         case RISCV_EXCP_LOAD_PAGE_FAULT:
1599         case RISCV_EXCP_STORE_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             } else {
1609                 /*
1610                  * The "Addr. Offset" field in transformed instruction is
1611                  * non-zero only for misaligned access.
1612                  */
1613                 tinst = riscv_transformed_insn(env, env->bins, tval);
1614             }
1615             break;
1616         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
1617         case RISCV_EXCP_INST_ADDR_MIS:
1618         case RISCV_EXCP_INST_ACCESS_FAULT:
1619         case RISCV_EXCP_INST_PAGE_FAULT:
1620             write_gva = env->two_stage_lookup;
1621             tval = env->badaddr;
1622             if (env->two_stage_indirect_lookup) {
1623                 /*
1624                  * special pseudoinstruction for G-stage fault taken while
1625                  * doing VS-stage page table walk.
1626                  */
1627                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1628             }
1629             break;
1630         case RISCV_EXCP_ILLEGAL_INST:
1631         case RISCV_EXCP_VIRT_INSTRUCTION_FAULT:
1632             tval = env->bins;
1633             break;
1634         default:
1635             break;
1636         }
1637         /* ecall is dispatched as one cause so translate based on mode */
1638         if (cause == RISCV_EXCP_U_ECALL) {
1639             assert(env->priv <= 3);
1640 
1641             if (env->priv == PRV_M) {
1642                 cause = RISCV_EXCP_M_ECALL;
1643             } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) {
1644                 cause = RISCV_EXCP_VS_ECALL;
1645             } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) {
1646                 cause = RISCV_EXCP_S_ECALL;
1647             } else if (env->priv == PRV_U) {
1648                 cause = RISCV_EXCP_U_ECALL;
1649             }
1650         }
1651     }
1652 
1653     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
1654                      riscv_cpu_get_trap_name(cause, async));
1655 
1656     qemu_log_mask(CPU_LOG_INT,
1657                   "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", "
1658                   "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n",
1659                   __func__, env->mhartid, async, cause, env->pc, tval,
1660                   riscv_cpu_get_trap_name(cause, async));
1661 
1662     if (env->priv <= PRV_S &&
1663             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
1664         /* handle the trap in S-mode */
1665         if (riscv_has_ext(env, RVH)) {
1666             uint64_t hdeleg = async ? env->hideleg : env->hedeleg;
1667 
1668             if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1)) {
1669                 /* Trap to VS mode */
1670                 /*
1671                  * See if we need to adjust cause. Yes if its VS mode interrupt
1672                  * no if hypervisor has delegated one of hs mode's interrupt
1673                  */
1674                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
1675                     cause == IRQ_VS_EXT) {
1676                     cause = cause - 1;
1677                 }
1678                 write_gva = false;
1679             } else if (riscv_cpu_virt_enabled(env)) {
1680                 /* Trap into HS mode, from virt */
1681                 riscv_cpu_swap_hypervisor_regs(env);
1682                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
1683                                          env->priv);
1684                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV,
1685                                          riscv_cpu_virt_enabled(env));
1686 
1687 
1688                 htval = env->guest_phys_fault_addr;
1689 
1690                 riscv_cpu_set_virt_enabled(env, 0);
1691             } else {
1692                 /* Trap into HS mode */
1693                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false);
1694                 htval = env->guest_phys_fault_addr;
1695             }
1696             env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva);
1697         }
1698 
1699         s = env->mstatus;
1700         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
1701         s = set_field(s, MSTATUS_SPP, env->priv);
1702         s = set_field(s, MSTATUS_SIE, 0);
1703         env->mstatus = s;
1704         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
1705         env->sepc = env->pc;
1706         env->stval = tval;
1707         env->htval = htval;
1708         env->htinst = tinst;
1709         env->pc = (env->stvec >> 2 << 2) +
1710             ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
1711         riscv_cpu_set_mode(env, PRV_S);
1712     } else {
1713         /* handle the trap in M-mode */
1714         if (riscv_has_ext(env, RVH)) {
1715             if (riscv_cpu_virt_enabled(env)) {
1716                 riscv_cpu_swap_hypervisor_regs(env);
1717             }
1718             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
1719                                      riscv_cpu_virt_enabled(env));
1720             if (riscv_cpu_virt_enabled(env) && tval) {
1721                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
1722             }
1723 
1724             mtval2 = env->guest_phys_fault_addr;
1725 
1726             /* Trapping to M mode, virt is disabled */
1727             riscv_cpu_set_virt_enabled(env, 0);
1728         }
1729 
1730         s = env->mstatus;
1731         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
1732         s = set_field(s, MSTATUS_MPP, env->priv);
1733         s = set_field(s, MSTATUS_MIE, 0);
1734         env->mstatus = s;
1735         env->mcause = cause | ~(((target_ulong)-1) >> async);
1736         env->mepc = env->pc;
1737         env->mtval = tval;
1738         env->mtval2 = mtval2;
1739         env->mtinst = tinst;
1740         env->pc = (env->mtvec >> 2 << 2) +
1741             ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
1742         riscv_cpu_set_mode(env, PRV_M);
1743     }
1744 
1745     /* NOTE: it is not necessary to yield load reservations here. It is only
1746      * necessary for an SC from "another hart" to cause a load reservation
1747      * to be yielded. Refer to the memory consistency model section of the
1748      * RISC-V ISA Specification.
1749      */
1750 
1751     env->two_stage_lookup = false;
1752     env->two_stage_indirect_lookup = false;
1753 #endif
1754     cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
1755 }
1756