xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision 02369f79)
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 "internals.h"
25 #include "pmu.h"
26 #include "exec/exec-all.h"
27 #include "instmap.h"
28 #include "tcg/tcg-op.h"
29 #include "trace.h"
30 #include "semihosting/common-semi.h"
31 #include "sysemu/cpu-timers.h"
32 #include "cpu_bits.h"
33 #include "debug.h"
34 
35 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
36 {
37 #ifdef CONFIG_USER_ONLY
38     return 0;
39 #else
40     if (ifetch) {
41         return env->priv;
42     }
43 
44     /* All priv -> mmu_idx mapping are here */
45     int mode = env->priv;
46     if (mode == PRV_M && get_field(env->mstatus, MSTATUS_MPRV)) {
47         mode = get_field(env->mstatus, MSTATUS_MPP);
48     }
49     if (mode == PRV_S && get_field(env->mstatus, MSTATUS_SUM)) {
50         return MMUIdx_S_SUM;
51     }
52     return mode;
53 #endif
54 }
55 
56 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
57                           target_ulong *cs_base, uint32_t *pflags)
58 {
59     CPUState *cs = env_cpu(env);
60     RISCVCPU *cpu = RISCV_CPU(cs);
61     RISCVExtStatus fs, vs;
62     uint32_t flags = 0;
63 
64     *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc;
65     *cs_base = 0;
66 
67     if (cpu->cfg.ext_zve32f) {
68         /*
69          * If env->vl equals to VLMAX, we can use generic vector operation
70          * expanders (GVEC) to accerlate the vector operations.
71          * However, as LMUL could be a fractional number. The maximum
72          * vector size can be operated might be less than 8 bytes,
73          * which is not supported by GVEC. So we set vl_eq_vlmax flag to true
74          * only when maxsz >= 8 bytes.
75          */
76         uint32_t vlmax = vext_get_vlmax(cpu, env->vtype);
77         uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW);
78         uint32_t maxsz = vlmax << sew;
79         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) &&
80                            (maxsz >= 8);
81         flags = FIELD_DP32(flags, TB_FLAGS, VILL, env->vill);
82         flags = FIELD_DP32(flags, TB_FLAGS, SEW, sew);
83         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
84                            FIELD_EX64(env->vtype, VTYPE, VLMUL));
85         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
86         flags = FIELD_DP32(flags, TB_FLAGS, VTA,
87                            FIELD_EX64(env->vtype, VTYPE, VTA));
88         flags = FIELD_DP32(flags, TB_FLAGS, VMA,
89                            FIELD_EX64(env->vtype, VTYPE, VMA));
90         flags = FIELD_DP32(flags, TB_FLAGS, VSTART_EQ_ZERO, env->vstart == 0);
91     } else {
92         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
93     }
94 
95 #ifdef CONFIG_USER_ONLY
96     fs = EXT_STATUS_DIRTY;
97     vs = EXT_STATUS_DIRTY;
98 #else
99     flags = FIELD_DP32(flags, TB_FLAGS, PRIV, env->priv);
100 
101     flags |= cpu_mmu_index(env, 0);
102     fs = get_field(env->mstatus, MSTATUS_FS);
103     vs = get_field(env->mstatus, MSTATUS_VS);
104 
105     if (env->virt_enabled) {
106         flags = FIELD_DP32(flags, TB_FLAGS, VIRT_ENABLED, 1);
107         /*
108          * Merge DISABLED and !DIRTY states using MIN.
109          * We will set both fields when dirtying.
110          */
111         fs = MIN(fs, get_field(env->mstatus_hs, MSTATUS_FS));
112         vs = MIN(vs, get_field(env->mstatus_hs, MSTATUS_VS));
113     }
114 
115     if (cpu->cfg.debug && !icount_enabled()) {
116         flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled);
117     }
118 #endif
119 
120     flags = FIELD_DP32(flags, TB_FLAGS, FS, fs);
121     flags = FIELD_DP32(flags, TB_FLAGS, VS, vs);
122     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
123     if (env->cur_pmmask < (env->xl == MXL_RV32 ? UINT32_MAX : UINT64_MAX)) {
124         flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
125     }
126     if (env->cur_pmbase != 0) {
127         flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1);
128     }
129 
130     *pflags = flags;
131 }
132 
133 void riscv_cpu_update_mask(CPURISCVState *env)
134 {
135     target_ulong mask = -1, base = 0;
136     /*
137      * TODO: Current RVJ spec does not specify
138      * how the extension interacts with XLEN.
139      */
140 #ifndef CONFIG_USER_ONLY
141     if (riscv_has_ext(env, RVJ)) {
142         switch (env->priv) {
143         case PRV_M:
144             if (env->mmte & M_PM_ENABLE) {
145                 mask = env->mpmmask;
146                 base = env->mpmbase;
147             }
148             break;
149         case PRV_S:
150             if (env->mmte & S_PM_ENABLE) {
151                 mask = env->spmmask;
152                 base = env->spmbase;
153             }
154             break;
155         case PRV_U:
156             if (env->mmte & U_PM_ENABLE) {
157                 mask = env->upmmask;
158                 base = env->upmbase;
159             }
160             break;
161         default:
162             g_assert_not_reached();
163         }
164     }
165 #endif
166     if (env->xl == MXL_RV32) {
167         env->cur_pmmask = mask & UINT32_MAX;
168         env->cur_pmbase = base & UINT32_MAX;
169     } else {
170         env->cur_pmmask = mask;
171         env->cur_pmbase = base;
172     }
173 }
174 
175 #ifndef CONFIG_USER_ONLY
176 
177 /*
178  * The HS-mode is allowed to configure priority only for the
179  * following VS-mode local interrupts:
180  *
181  * 0  (Reserved interrupt, reads as zero)
182  * 1  Supervisor software interrupt
183  * 4  (Reserved interrupt, reads as zero)
184  * 5  Supervisor timer interrupt
185  * 8  (Reserved interrupt, reads as zero)
186  * 13 (Reserved interrupt)
187  * 14 "
188  * 15 "
189  * 16 "
190  * 17 "
191  * 18 "
192  * 19 "
193  * 20 "
194  * 21 "
195  * 22 "
196  * 23 "
197  */
198 
199 static const int hviprio_index2irq[] = {
200     0, 1, 4, 5, 8, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 };
201 static const int hviprio_index2rdzero[] = {
202     1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
203 
204 int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero)
205 {
206     if (index < 0 || ARRAY_SIZE(hviprio_index2irq) <= index) {
207         return -EINVAL;
208     }
209 
210     if (out_irq) {
211         *out_irq = hviprio_index2irq[index];
212     }
213 
214     if (out_rdzero) {
215         *out_rdzero = hviprio_index2rdzero[index];
216     }
217 
218     return 0;
219 }
220 
221 /*
222  * Default priorities of local interrupts are defined in the
223  * RISC-V Advanced Interrupt Architecture specification.
224  *
225  * ----------------------------------------------------------------
226  *  Default  |
227  *  Priority | Major Interrupt Numbers
228  * ----------------------------------------------------------------
229  *  Highest  | 47, 23, 46, 45, 22, 44,
230  *           | 43, 21, 42, 41, 20, 40
231  *           |
232  *           | 11 (0b),  3 (03),  7 (07)
233  *           |  9 (09),  1 (01),  5 (05)
234  *           | 12 (0c)
235  *           | 10 (0a),  2 (02),  6 (06)
236  *           |
237  *           | 39, 19, 38, 37, 18, 36,
238  *  Lowest   | 35, 17, 34, 33, 16, 32
239  * ----------------------------------------------------------------
240  */
241 static const uint8_t default_iprio[64] = {
242     /* Custom interrupts 48 to 63 */
243     [63] = IPRIO_MMAXIPRIO,
244     [62] = IPRIO_MMAXIPRIO,
245     [61] = IPRIO_MMAXIPRIO,
246     [60] = IPRIO_MMAXIPRIO,
247     [59] = IPRIO_MMAXIPRIO,
248     [58] = IPRIO_MMAXIPRIO,
249     [57] = IPRIO_MMAXIPRIO,
250     [56] = IPRIO_MMAXIPRIO,
251     [55] = IPRIO_MMAXIPRIO,
252     [54] = IPRIO_MMAXIPRIO,
253     [53] = IPRIO_MMAXIPRIO,
254     [52] = IPRIO_MMAXIPRIO,
255     [51] = IPRIO_MMAXIPRIO,
256     [50] = IPRIO_MMAXIPRIO,
257     [49] = IPRIO_MMAXIPRIO,
258     [48] = IPRIO_MMAXIPRIO,
259 
260     /* Custom interrupts 24 to 31 */
261     [31] = IPRIO_MMAXIPRIO,
262     [30] = IPRIO_MMAXIPRIO,
263     [29] = IPRIO_MMAXIPRIO,
264     [28] = IPRIO_MMAXIPRIO,
265     [27] = IPRIO_MMAXIPRIO,
266     [26] = IPRIO_MMAXIPRIO,
267     [25] = IPRIO_MMAXIPRIO,
268     [24] = IPRIO_MMAXIPRIO,
269 
270     [47] = IPRIO_DEFAULT_UPPER,
271     [23] = IPRIO_DEFAULT_UPPER + 1,
272     [46] = IPRIO_DEFAULT_UPPER + 2,
273     [45] = IPRIO_DEFAULT_UPPER + 3,
274     [22] = IPRIO_DEFAULT_UPPER + 4,
275     [44] = IPRIO_DEFAULT_UPPER + 5,
276 
277     [43] = IPRIO_DEFAULT_UPPER + 6,
278     [21] = IPRIO_DEFAULT_UPPER + 7,
279     [42] = IPRIO_DEFAULT_UPPER + 8,
280     [41] = IPRIO_DEFAULT_UPPER + 9,
281     [20] = IPRIO_DEFAULT_UPPER + 10,
282     [40] = IPRIO_DEFAULT_UPPER + 11,
283 
284     [11] = IPRIO_DEFAULT_M,
285     [3]  = IPRIO_DEFAULT_M + 1,
286     [7]  = IPRIO_DEFAULT_M + 2,
287 
288     [9]  = IPRIO_DEFAULT_S,
289     [1]  = IPRIO_DEFAULT_S + 1,
290     [5]  = IPRIO_DEFAULT_S + 2,
291 
292     [12] = IPRIO_DEFAULT_SGEXT,
293 
294     [10] = IPRIO_DEFAULT_VS,
295     [2]  = IPRIO_DEFAULT_VS + 1,
296     [6]  = IPRIO_DEFAULT_VS + 2,
297 
298     [39] = IPRIO_DEFAULT_LOWER,
299     [19] = IPRIO_DEFAULT_LOWER + 1,
300     [38] = IPRIO_DEFAULT_LOWER + 2,
301     [37] = IPRIO_DEFAULT_LOWER + 3,
302     [18] = IPRIO_DEFAULT_LOWER + 4,
303     [36] = IPRIO_DEFAULT_LOWER + 5,
304 
305     [35] = IPRIO_DEFAULT_LOWER + 6,
306     [17] = IPRIO_DEFAULT_LOWER + 7,
307     [34] = IPRIO_DEFAULT_LOWER + 8,
308     [33] = IPRIO_DEFAULT_LOWER + 9,
309     [16] = IPRIO_DEFAULT_LOWER + 10,
310     [32] = IPRIO_DEFAULT_LOWER + 11,
311 };
312 
313 uint8_t riscv_cpu_default_priority(int irq)
314 {
315     if (irq < 0 || irq > 63) {
316         return IPRIO_MMAXIPRIO;
317     }
318 
319     return default_iprio[irq] ? default_iprio[irq] : IPRIO_MMAXIPRIO;
320 };
321 
322 static int riscv_cpu_pending_to_irq(CPURISCVState *env,
323                                     int extirq, unsigned int extirq_def_prio,
324                                     uint64_t pending, uint8_t *iprio)
325 {
326     int irq, best_irq = RISCV_EXCP_NONE;
327     unsigned int prio, best_prio = UINT_MAX;
328 
329     if (!pending) {
330         return RISCV_EXCP_NONE;
331     }
332 
333     irq = ctz64(pending);
334     if (!((extirq == IRQ_M_EXT) ? riscv_cpu_cfg(env)->ext_smaia :
335                                   riscv_cpu_cfg(env)->ext_ssaia)) {
336         return irq;
337     }
338 
339     pending = pending >> irq;
340     while (pending) {
341         prio = iprio[irq];
342         if (!prio) {
343             if (irq == extirq) {
344                 prio = extirq_def_prio;
345             } else {
346                 prio = (riscv_cpu_default_priority(irq) < extirq_def_prio) ?
347                        1 : IPRIO_MMAXIPRIO;
348             }
349         }
350         if ((pending & 0x1) && (prio <= best_prio)) {
351             best_irq = irq;
352             best_prio = prio;
353         }
354         irq++;
355         pending = pending >> 1;
356     }
357 
358     return best_irq;
359 }
360 
361 uint64_t riscv_cpu_all_pending(CPURISCVState *env)
362 {
363     uint32_t gein = get_field(env->hstatus, HSTATUS_VGEIN);
364     uint64_t vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
365     uint64_t vstip = (env->vstime_irq) ? MIP_VSTIP : 0;
366 
367     return (env->mip | vsgein | vstip) & env->mie;
368 }
369 
370 int riscv_cpu_mirq_pending(CPURISCVState *env)
371 {
372     uint64_t irqs = riscv_cpu_all_pending(env) & ~env->mideleg &
373                     ~(MIP_SGEIP | MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
374 
375     return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
376                                     irqs, env->miprio);
377 }
378 
379 int riscv_cpu_sirq_pending(CPURISCVState *env)
380 {
381     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
382                     ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
383 
384     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
385                                     irqs, env->siprio);
386 }
387 
388 int riscv_cpu_vsirq_pending(CPURISCVState *env)
389 {
390     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
391                     (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
392 
393     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
394                                     irqs >> 1, env->hviprio);
395 }
396 
397 static int riscv_cpu_local_irq_pending(CPURISCVState *env)
398 {
399     int virq;
400     uint64_t irqs, pending, mie, hsie, vsie;
401 
402     /* Determine interrupt enable state of all privilege modes */
403     if (env->virt_enabled) {
404         mie = 1;
405         hsie = 1;
406         vsie = (env->priv < PRV_S) ||
407                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
408     } else {
409         mie = (env->priv < PRV_M) ||
410               (env->priv == PRV_M && get_field(env->mstatus, MSTATUS_MIE));
411         hsie = (env->priv < PRV_S) ||
412                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
413         vsie = 0;
414     }
415 
416     /* Determine all pending interrupts */
417     pending = riscv_cpu_all_pending(env);
418 
419     /* Check M-mode interrupts */
420     irqs = pending & ~env->mideleg & -mie;
421     if (irqs) {
422         return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
423                                         irqs, env->miprio);
424     }
425 
426     /* Check HS-mode interrupts */
427     irqs = pending & env->mideleg & ~env->hideleg & -hsie;
428     if (irqs) {
429         return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
430                                         irqs, env->siprio);
431     }
432 
433     /* Check VS-mode interrupts */
434     irqs = pending & env->mideleg & env->hideleg & -vsie;
435     if (irqs) {
436         virq = riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
437                                         irqs >> 1, env->hviprio);
438         return (virq <= 0) ? virq : virq + 1;
439     }
440 
441     /* Indicate no pending interrupt */
442     return RISCV_EXCP_NONE;
443 }
444 
445 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
446 {
447     if (interrupt_request & CPU_INTERRUPT_HARD) {
448         RISCVCPU *cpu = RISCV_CPU(cs);
449         CPURISCVState *env = &cpu->env;
450         int interruptno = riscv_cpu_local_irq_pending(env);
451         if (interruptno >= 0) {
452             cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno;
453             riscv_cpu_do_interrupt(cs);
454             return true;
455         }
456     }
457     return false;
458 }
459 
460 /* Return true is floating point support is currently enabled */
461 bool riscv_cpu_fp_enabled(CPURISCVState *env)
462 {
463     if (env->mstatus & MSTATUS_FS) {
464         if (env->virt_enabled && !(env->mstatus_hs & MSTATUS_FS)) {
465             return false;
466         }
467         return true;
468     }
469 
470     return false;
471 }
472 
473 /* Return true is vector support is currently enabled */
474 bool riscv_cpu_vector_enabled(CPURISCVState *env)
475 {
476     if (env->mstatus & MSTATUS_VS) {
477         if (env->virt_enabled && !(env->mstatus_hs & MSTATUS_VS)) {
478             return false;
479         }
480         return true;
481     }
482 
483     return false;
484 }
485 
486 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
487 {
488     uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM |
489                             MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
490                             MSTATUS64_UXL | MSTATUS_VS;
491 
492     if (riscv_has_ext(env, RVF)) {
493         mstatus_mask |= MSTATUS_FS;
494     }
495     bool current_virt = env->virt_enabled;
496 
497     g_assert(riscv_has_ext(env, RVH));
498 
499     if (current_virt) {
500         /* Current V=1 and we are about to change to V=0 */
501         env->vsstatus = env->mstatus & mstatus_mask;
502         env->mstatus &= ~mstatus_mask;
503         env->mstatus |= env->mstatus_hs;
504 
505         env->vstvec = env->stvec;
506         env->stvec = env->stvec_hs;
507 
508         env->vsscratch = env->sscratch;
509         env->sscratch = env->sscratch_hs;
510 
511         env->vsepc = env->sepc;
512         env->sepc = env->sepc_hs;
513 
514         env->vscause = env->scause;
515         env->scause = env->scause_hs;
516 
517         env->vstval = env->stval;
518         env->stval = env->stval_hs;
519 
520         env->vsatp = env->satp;
521         env->satp = env->satp_hs;
522     } else {
523         /* Current V=0 and we are about to change to V=1 */
524         env->mstatus_hs = env->mstatus & mstatus_mask;
525         env->mstatus &= ~mstatus_mask;
526         env->mstatus |= env->vsstatus;
527 
528         env->stvec_hs = env->stvec;
529         env->stvec = env->vstvec;
530 
531         env->sscratch_hs = env->sscratch;
532         env->sscratch = env->vsscratch;
533 
534         env->sepc_hs = env->sepc;
535         env->sepc = env->vsepc;
536 
537         env->scause_hs = env->scause;
538         env->scause = env->vscause;
539 
540         env->stval_hs = env->stval;
541         env->stval = env->vstval;
542 
543         env->satp_hs = env->satp;
544         env->satp = env->vsatp;
545     }
546 }
547 
548 target_ulong riscv_cpu_get_geilen(CPURISCVState *env)
549 {
550     if (!riscv_has_ext(env, RVH)) {
551         return 0;
552     }
553 
554     return env->geilen;
555 }
556 
557 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen)
558 {
559     if (!riscv_has_ext(env, RVH)) {
560         return;
561     }
562 
563     if (geilen > (TARGET_LONG_BITS - 1)) {
564         return;
565     }
566 
567     env->geilen = geilen;
568 }
569 
570 /* This function can only be called to set virt when RVH is enabled */
571 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
572 {
573     /* Flush the TLB on all virt mode changes. */
574     if (env->virt_enabled != enable) {
575         tlb_flush(env_cpu(env));
576     }
577 
578     env->virt_enabled = enable;
579 
580     if (enable) {
581         /*
582          * The guest external interrupts from an interrupt controller are
583          * delivered only when the Guest/VM is running (i.e. V=1). This means
584          * any guest external interrupt which is triggered while the Guest/VM
585          * is not running (i.e. V=0) will be missed on QEMU resulting in guest
586          * with sluggish response to serial console input and other I/O events.
587          *
588          * To solve this, we check and inject interrupt after setting V=1.
589          */
590         riscv_cpu_update_mip(env, 0, 0);
591     }
592 }
593 
594 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts)
595 {
596     CPURISCVState *env = &cpu->env;
597     if (env->miclaim & interrupts) {
598         return -1;
599     } else {
600         env->miclaim |= interrupts;
601         return 0;
602     }
603 }
604 
605 uint64_t riscv_cpu_update_mip(CPURISCVState *env, uint64_t mask,
606                               uint64_t value)
607 {
608     CPUState *cs = env_cpu(env);
609     uint64_t gein, vsgein = 0, vstip = 0, old = env->mip;
610 
611     if (env->virt_enabled) {
612         gein = get_field(env->hstatus, HSTATUS_VGEIN);
613         vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
614     }
615 
616     vstip = env->vstime_irq ? MIP_VSTIP : 0;
617 
618     QEMU_IOTHREAD_LOCK_GUARD();
619 
620     env->mip = (env->mip & ~mask) | (value & mask);
621 
622     if (env->mip | vsgein | vstip) {
623         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
624     } else {
625         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
626     }
627 
628     return old;
629 }
630 
631 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void *),
632                              void *arg)
633 {
634     env->rdtime_fn = fn;
635     env->rdtime_fn_arg = arg;
636 }
637 
638 void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv,
639                                    int (*rmw_fn)(void *arg,
640                                                  target_ulong reg,
641                                                  target_ulong *val,
642                                                  target_ulong new_val,
643                                                  target_ulong write_mask),
644                                    void *rmw_fn_arg)
645 {
646     if (priv <= PRV_M) {
647         env->aia_ireg_rmw_fn[priv] = rmw_fn;
648         env->aia_ireg_rmw_fn_arg[priv] = rmw_fn_arg;
649     }
650 }
651 
652 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv)
653 {
654     g_assert(newpriv <= PRV_M && newpriv != PRV_RESERVED);
655 
656     if (icount_enabled() && newpriv != env->priv) {
657         riscv_itrigger_update_priv(env);
658     }
659     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
660     env->priv = newpriv;
661     env->xl = cpu_recompute_xl(env);
662     riscv_cpu_update_mask(env);
663 
664     /*
665      * Clear the load reservation - otherwise a reservation placed in one
666      * context/process can be used by another, resulting in an SC succeeding
667      * incorrectly. Version 2.2 of the ISA specification explicitly requires
668      * this behaviour, while later revisions say that the kernel "should" use
669      * an SC instruction to force the yielding of a load reservation on a
670      * preemptive context switch. As a result, do both.
671      */
672     env->load_res = -1;
673 }
674 
675 /*
676  * get_physical_address_pmp - check PMP permission for this physical address
677  *
678  * Match the PMP region and check permission for this physical address and it's
679  * TLB page. Returns 0 if the permission checking was successful
680  *
681  * @env: CPURISCVState
682  * @prot: The returned protection attributes
683  * @tlb_size: TLB page size containing addr. It could be modified after PMP
684  *            permission checking. NULL if not set TLB page for addr.
685  * @addr: The physical address to be checked permission
686  * @access_type: The type of MMU access
687  * @mode: Indicates current privilege level.
688  */
689 static int get_physical_address_pmp(CPURISCVState *env, int *prot,
690                                     target_ulong *tlb_size, hwaddr addr,
691                                     int size, MMUAccessType access_type,
692                                     int mode)
693 {
694     pmp_priv_t pmp_priv;
695     int pmp_index = -1;
696 
697     if (!riscv_cpu_cfg(env)->pmp) {
698         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
699         return TRANSLATE_SUCCESS;
700     }
701 
702     pmp_index = pmp_hart_has_privs(env, addr, size, 1 << access_type,
703                                    &pmp_priv, mode);
704     if (pmp_index < 0) {
705         *prot = 0;
706         return TRANSLATE_PMP_FAIL;
707     }
708 
709     *prot = pmp_priv_to_page_prot(pmp_priv);
710     if ((tlb_size != NULL) && pmp_index != MAX_RISCV_PMPS) {
711         target_ulong tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1);
712         target_ulong tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1;
713 
714         *tlb_size = pmp_get_tlb_size(env, pmp_index, tlb_sa, tlb_ea);
715     }
716 
717     return TRANSLATE_SUCCESS;
718 }
719 
720 /*
721  * get_physical_address - get the physical address for this virtual address
722  *
723  * Do a page table walk to obtain the physical address corresponding to a
724  * virtual address. Returns 0 if the translation was successful
725  *
726  * Adapted from Spike's mmu_t::translate and mmu_t::walk
727  *
728  * @env: CPURISCVState
729  * @physical: This will be set to the calculated physical address
730  * @prot: The returned protection attributes
731  * @addr: The virtual address or guest physical address to be translated
732  * @fault_pte_addr: If not NULL, this will be set to fault pte address
733  *                  when a error occurs on pte address translation.
734  *                  This will already be shifted to match htval.
735  * @access_type: The type of MMU access
736  * @mmu_idx: Indicates current privilege level
737  * @first_stage: Are we in first stage translation?
738  *               Second stage is used for hypervisor guest translation
739  * @two_stage: Are we going to perform two stage translation
740  * @is_debug: Is this access from a debugger or the monitor?
741  */
742 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
743                                 int *prot, vaddr addr,
744                                 target_ulong *fault_pte_addr,
745                                 int access_type, int mmu_idx,
746                                 bool first_stage, bool two_stage,
747                                 bool is_debug)
748 {
749     /*
750      * NOTE: the env->pc value visible here will not be
751      * correct, but the value visible to the exception handler
752      * (riscv_cpu_do_interrupt) is correct
753      */
754     MemTxResult res;
755     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
756     int mode = mmuidx_priv(mmu_idx);
757     bool use_background = false;
758     hwaddr ppn;
759     int napot_bits = 0;
760     target_ulong napot_mask;
761 
762     /*
763      * Check if we should use the background registers for the two
764      * stage translation. We don't need to check if we actually need
765      * two stage translation as that happened before this function
766      * was called. Background registers will be used if the guest has
767      * forced a two stage translation to be on (in HS or M mode).
768      */
769     if (!env->virt_enabled && two_stage) {
770         use_background = true;
771     }
772 
773     /*
774      * MPRV does not affect the virtual-machine load/store
775      * instructions, HLV, HLVX, and HSV.
776      */
777     if (mmuidx_2stage(mmu_idx)) {
778         mode = get_field(env->hstatus, HSTATUS_SPVP);
779     }
780 
781     if (first_stage == false) {
782         /*
783          * We are in stage 2 translation, this is similar to stage 1.
784          * Stage 2 is always taken as U-mode
785          */
786         mode = PRV_U;
787     }
788 
789     if (mode == PRV_M || !riscv_cpu_cfg(env)->mmu) {
790         *physical = addr;
791         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
792         return TRANSLATE_SUCCESS;
793     }
794 
795     *prot = 0;
796 
797     hwaddr base;
798     int levels, ptidxbits, ptesize, vm, sum, mxr, widened;
799 
800     if (first_stage == true) {
801         mxr = get_field(env->mstatus, MSTATUS_MXR);
802     } else {
803         mxr = get_field(env->vsstatus, MSTATUS_MXR);
804     }
805 
806     if (first_stage == true) {
807         if (use_background) {
808             if (riscv_cpu_mxl(env) == MXL_RV32) {
809                 base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT;
810                 vm = get_field(env->vsatp, SATP32_MODE);
811             } else {
812                 base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT;
813                 vm = get_field(env->vsatp, SATP64_MODE);
814             }
815         } else {
816             if (riscv_cpu_mxl(env) == MXL_RV32) {
817                 base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT;
818                 vm = get_field(env->satp, SATP32_MODE);
819             } else {
820                 base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT;
821                 vm = get_field(env->satp, SATP64_MODE);
822             }
823         }
824         widened = 0;
825     } else {
826         if (riscv_cpu_mxl(env) == MXL_RV32) {
827             base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT;
828             vm = get_field(env->hgatp, SATP32_MODE);
829         } else {
830             base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT;
831             vm = get_field(env->hgatp, SATP64_MODE);
832         }
833         widened = 2;
834     }
835     /* status.SUM will be ignored if execute on background */
836     sum = mmuidx_sum(mmu_idx) || use_background || is_debug;
837     switch (vm) {
838     case VM_1_10_SV32:
839       levels = 2; ptidxbits = 10; ptesize = 4; break;
840     case VM_1_10_SV39:
841       levels = 3; ptidxbits = 9; ptesize = 8; break;
842     case VM_1_10_SV48:
843       levels = 4; ptidxbits = 9; ptesize = 8; break;
844     case VM_1_10_SV57:
845       levels = 5; ptidxbits = 9; ptesize = 8; break;
846     case VM_1_10_MBARE:
847         *physical = addr;
848         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
849         return TRANSLATE_SUCCESS;
850     default:
851       g_assert_not_reached();
852     }
853 
854     CPUState *cs = env_cpu(env);
855     int va_bits = PGSHIFT + levels * ptidxbits + widened;
856     target_ulong mask, masked_msbs;
857 
858     if (TARGET_LONG_BITS > (va_bits - 1)) {
859         mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1;
860     } else {
861         mask = 0;
862     }
863     masked_msbs = (addr >> (va_bits - 1)) & mask;
864 
865     if (masked_msbs != 0 && masked_msbs != mask) {
866         return TRANSLATE_FAIL;
867     }
868 
869     int ptshift = (levels - 1) * ptidxbits;
870     int i;
871 
872 #if !TCG_OVERSIZED_GUEST
873 restart:
874 #endif
875     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
876         target_ulong idx;
877         if (i == 0) {
878             idx = (addr >> (PGSHIFT + ptshift)) &
879                            ((1 << (ptidxbits + widened)) - 1);
880         } else {
881             idx = (addr >> (PGSHIFT + ptshift)) &
882                            ((1 << ptidxbits) - 1);
883         }
884 
885         /* check that physical address of PTE is legal */
886         hwaddr pte_addr;
887 
888         if (two_stage && first_stage) {
889             int vbase_prot;
890             hwaddr vbase;
891 
892             /* Do the second stage translation on the base PTE address. */
893             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
894                                                  base, NULL, MMU_DATA_LOAD,
895                                                  mmu_idx, false, true,
896                                                  is_debug);
897 
898             if (vbase_ret != TRANSLATE_SUCCESS) {
899                 if (fault_pte_addr) {
900                     *fault_pte_addr = (base + idx * ptesize) >> 2;
901                 }
902                 return TRANSLATE_G_STAGE_FAIL;
903             }
904 
905             pte_addr = vbase + idx * ptesize;
906         } else {
907             pte_addr = base + idx * ptesize;
908         }
909 
910         int pmp_prot;
911         int pmp_ret = get_physical_address_pmp(env, &pmp_prot, NULL, pte_addr,
912                                                sizeof(target_ulong),
913                                                MMU_DATA_LOAD, PRV_S);
914         if (pmp_ret != TRANSLATE_SUCCESS) {
915             return TRANSLATE_PMP_FAIL;
916         }
917 
918         target_ulong pte;
919         if (riscv_cpu_mxl(env) == MXL_RV32) {
920             pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
921         } else {
922             pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
923         }
924 
925         if (res != MEMTX_OK) {
926             return TRANSLATE_FAIL;
927         }
928 
929         bool pbmte = env->menvcfg & MENVCFG_PBMTE;
930         bool hade = env->menvcfg & MENVCFG_HADE;
931 
932         if (first_stage && two_stage && env->virt_enabled) {
933             pbmte = pbmte && (env->henvcfg & HENVCFG_PBMTE);
934             hade = hade && (env->henvcfg & HENVCFG_HADE);
935         }
936 
937         if (riscv_cpu_sxl(env) == MXL_RV32) {
938             ppn = pte >> PTE_PPN_SHIFT;
939         } else if (pbmte || riscv_cpu_cfg(env)->ext_svnapot) {
940             ppn = (pte & (target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT;
941         } else {
942             ppn = pte >> PTE_PPN_SHIFT;
943             if ((pte & ~(target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT) {
944                 return TRANSLATE_FAIL;
945             }
946         }
947 
948         if (!(pte & PTE_V)) {
949             /* Invalid PTE */
950             return TRANSLATE_FAIL;
951         } else if (!pbmte && (pte & PTE_PBMT)) {
952             return TRANSLATE_FAIL;
953         } else if (!(pte & (PTE_R | PTE_W | PTE_X))) {
954             /* Inner PTE, continue walking */
955             if (pte & (PTE_D | PTE_A | PTE_U | PTE_ATTR)) {
956                 return TRANSLATE_FAIL;
957             }
958             base = ppn << PGSHIFT;
959         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) {
960             /* Reserved leaf PTE flags: PTE_W */
961             return TRANSLATE_FAIL;
962         } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) {
963             /* Reserved leaf PTE flags: PTE_W + PTE_X */
964             return TRANSLATE_FAIL;
965         } else if ((pte & PTE_U) && ((mode != PRV_U) &&
966                    (!sum || access_type == MMU_INST_FETCH))) {
967             /* User PTE flags when not U mode and mstatus.SUM is not set,
968                or the access type is an instruction fetch */
969             return TRANSLATE_FAIL;
970         } else if (!(pte & PTE_U) && (mode != PRV_S)) {
971             /* Supervisor PTE flags when not S mode */
972             return TRANSLATE_FAIL;
973         } else if (ppn & ((1ULL << ptshift) - 1)) {
974             /* Misaligned PPN */
975             return TRANSLATE_FAIL;
976         } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) ||
977                    ((pte & PTE_X) && mxr))) {
978             /* Read access check failed */
979             return TRANSLATE_FAIL;
980         } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) {
981             /* Write access check failed */
982             return TRANSLATE_FAIL;
983         } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) {
984             /* Fetch access check failed */
985             return TRANSLATE_FAIL;
986         } else {
987             /* if necessary, set accessed and dirty bits. */
988             target_ulong updated_pte = pte | PTE_A |
989                 (access_type == MMU_DATA_STORE ? PTE_D : 0);
990 
991             /* Page table updates need to be atomic with MTTCG enabled */
992             if (updated_pte != pte) {
993                 if (!hade) {
994                     return TRANSLATE_FAIL;
995                 }
996 
997                 /*
998                  * - if accessed or dirty bits need updating, and the PTE is
999                  *   in RAM, then we do so atomically with a compare and swap.
1000                  * - if the PTE is in IO space or ROM, then it can't be updated
1001                  *   and we return TRANSLATE_FAIL.
1002                  * - if the PTE changed by the time we went to update it, then
1003                  *   it is no longer valid and we must re-walk the page table.
1004                  */
1005                 MemoryRegion *mr;
1006                 hwaddr l = sizeof(target_ulong), addr1;
1007                 mr = address_space_translate(cs->as, pte_addr, &addr1, &l,
1008                                              false, MEMTXATTRS_UNSPECIFIED);
1009                 if (memory_region_is_ram(mr)) {
1010                     target_ulong *pte_pa =
1011                         qemu_map_ram_ptr(mr->ram_block, addr1);
1012 #if TCG_OVERSIZED_GUEST
1013                     /*
1014                      * MTTCG is not enabled on oversized TCG guests so
1015                      * page table updates do not need to be atomic
1016                      */
1017                     *pte_pa = pte = updated_pte;
1018 #else
1019                     target_ulong old_pte =
1020                         qatomic_cmpxchg(pte_pa, pte, updated_pte);
1021                     if (old_pte != pte) {
1022                         goto restart;
1023                     } else {
1024                         pte = updated_pte;
1025                     }
1026 #endif
1027                 } else {
1028                     /*
1029                      * misconfigured PTE in ROM (AD bits are not preset) or
1030                      * PTE is in IO space and can't be updated atomically
1031                      */
1032                     return TRANSLATE_FAIL;
1033                 }
1034             }
1035 
1036             /*
1037              * for superpage mappings, make a fake leaf PTE for the TLB's
1038              * benefit.
1039              */
1040             target_ulong vpn = addr >> PGSHIFT;
1041 
1042             if (riscv_cpu_cfg(env)->ext_svnapot && (pte & PTE_N)) {
1043                 napot_bits = ctzl(ppn) + 1;
1044                 if ((i != (levels - 1)) || (napot_bits != 4)) {
1045                     return TRANSLATE_FAIL;
1046                 }
1047             }
1048 
1049             napot_mask = (1 << napot_bits) - 1;
1050             *physical = (((ppn & ~napot_mask) | (vpn & napot_mask) |
1051                           (vpn & (((target_ulong)1 << ptshift) - 1))
1052                          ) << PGSHIFT) | (addr & ~TARGET_PAGE_MASK);
1053 
1054             /* set permissions on the TLB entry */
1055             if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) {
1056                 *prot |= PAGE_READ;
1057             }
1058             if (pte & PTE_X) {
1059                 *prot |= PAGE_EXEC;
1060             }
1061             /*
1062              * add write permission on stores or if the page is already dirty,
1063              * so that we TLB miss on later writes to update the dirty bit
1064              */
1065             if ((pte & PTE_W) &&
1066                 (access_type == MMU_DATA_STORE || (pte & PTE_D))) {
1067                 *prot |= PAGE_WRITE;
1068             }
1069             return TRANSLATE_SUCCESS;
1070         }
1071     }
1072     return TRANSLATE_FAIL;
1073 }
1074 
1075 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
1076                                 MMUAccessType access_type, bool pmp_violation,
1077                                 bool first_stage, bool two_stage,
1078                                 bool two_stage_indirect)
1079 {
1080     CPUState *cs = env_cpu(env);
1081     int page_fault_exceptions, vm;
1082     uint64_t stap_mode;
1083 
1084     if (riscv_cpu_mxl(env) == MXL_RV32) {
1085         stap_mode = SATP32_MODE;
1086     } else {
1087         stap_mode = SATP64_MODE;
1088     }
1089 
1090     if (first_stage) {
1091         vm = get_field(env->satp, stap_mode);
1092     } else {
1093         vm = get_field(env->hgatp, stap_mode);
1094     }
1095 
1096     page_fault_exceptions = vm != VM_1_10_MBARE && !pmp_violation;
1097 
1098     switch (access_type) {
1099     case MMU_INST_FETCH:
1100         if (env->virt_enabled && !first_stage) {
1101             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
1102         } else {
1103             cs->exception_index = page_fault_exceptions ?
1104                 RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT;
1105         }
1106         break;
1107     case MMU_DATA_LOAD:
1108         if (two_stage && !first_stage) {
1109             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
1110         } else {
1111             cs->exception_index = page_fault_exceptions ?
1112                 RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT;
1113         }
1114         break;
1115     case MMU_DATA_STORE:
1116         if (two_stage && !first_stage) {
1117             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
1118         } else {
1119             cs->exception_index = page_fault_exceptions ?
1120                 RISCV_EXCP_STORE_PAGE_FAULT :
1121                 RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1122         }
1123         break;
1124     default:
1125         g_assert_not_reached();
1126     }
1127     env->badaddr = address;
1128     env->two_stage_lookup = two_stage;
1129     env->two_stage_indirect_lookup = two_stage_indirect;
1130 }
1131 
1132 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
1133 {
1134     RISCVCPU *cpu = RISCV_CPU(cs);
1135     CPURISCVState *env = &cpu->env;
1136     hwaddr phys_addr;
1137     int prot;
1138     int mmu_idx = cpu_mmu_index(&cpu->env, false);
1139 
1140     if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx,
1141                              true, env->virt_enabled, true)) {
1142         return -1;
1143     }
1144 
1145     if (env->virt_enabled) {
1146         if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL,
1147                                  0, mmu_idx, false, true, true)) {
1148             return -1;
1149         }
1150     }
1151 
1152     return phys_addr & TARGET_PAGE_MASK;
1153 }
1154 
1155 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
1156                                      vaddr addr, unsigned size,
1157                                      MMUAccessType access_type,
1158                                      int mmu_idx, MemTxAttrs attrs,
1159                                      MemTxResult response, uintptr_t retaddr)
1160 {
1161     RISCVCPU *cpu = RISCV_CPU(cs);
1162     CPURISCVState *env = &cpu->env;
1163 
1164     if (access_type == MMU_DATA_STORE) {
1165         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1166     } else if (access_type == MMU_DATA_LOAD) {
1167         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
1168     } else {
1169         cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT;
1170     }
1171 
1172     env->badaddr = addr;
1173     env->two_stage_lookup = env->virt_enabled || mmuidx_2stage(mmu_idx);
1174     env->two_stage_indirect_lookup = false;
1175     cpu_loop_exit_restore(cs, retaddr);
1176 }
1177 
1178 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
1179                                    MMUAccessType access_type, int mmu_idx,
1180                                    uintptr_t retaddr)
1181 {
1182     RISCVCPU *cpu = RISCV_CPU(cs);
1183     CPURISCVState *env = &cpu->env;
1184     switch (access_type) {
1185     case MMU_INST_FETCH:
1186         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
1187         break;
1188     case MMU_DATA_LOAD:
1189         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
1190         break;
1191     case MMU_DATA_STORE:
1192         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
1193         break;
1194     default:
1195         g_assert_not_reached();
1196     }
1197     env->badaddr = addr;
1198     env->two_stage_lookup = env->virt_enabled || mmuidx_2stage(mmu_idx);
1199     env->two_stage_indirect_lookup = false;
1200     cpu_loop_exit_restore(cs, retaddr);
1201 }
1202 
1203 
1204 static void pmu_tlb_fill_incr_ctr(RISCVCPU *cpu, MMUAccessType access_type)
1205 {
1206     enum riscv_pmu_event_idx pmu_event_type;
1207 
1208     switch (access_type) {
1209     case MMU_INST_FETCH:
1210         pmu_event_type = RISCV_PMU_EVENT_CACHE_ITLB_PREFETCH_MISS;
1211         break;
1212     case MMU_DATA_LOAD:
1213         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_READ_MISS;
1214         break;
1215     case MMU_DATA_STORE:
1216         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_WRITE_MISS;
1217         break;
1218     default:
1219         return;
1220     }
1221 
1222     riscv_pmu_incr_ctr(cpu, pmu_event_type);
1223 }
1224 
1225 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
1226                         MMUAccessType access_type, int mmu_idx,
1227                         bool probe, uintptr_t retaddr)
1228 {
1229     RISCVCPU *cpu = RISCV_CPU(cs);
1230     CPURISCVState *env = &cpu->env;
1231     vaddr im_address;
1232     hwaddr pa = 0;
1233     int prot, prot2, prot_pmp;
1234     bool pmp_violation = false;
1235     bool first_stage_error = true;
1236     bool two_stage_lookup = false;
1237     bool two_stage_indirect_error = false;
1238     int ret = TRANSLATE_FAIL;
1239     int mode = mmu_idx;
1240     /* default TLB page size */
1241     target_ulong tlb_size = TARGET_PAGE_SIZE;
1242 
1243     env->guest_phys_fault_addr = 0;
1244 
1245     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
1246                   __func__, address, access_type, mmu_idx);
1247 
1248     /*
1249      * MPRV does not affect the virtual-machine load/store
1250      * instructions, HLV, HLVX, and HSV.
1251      */
1252     if (mmuidx_2stage(mmu_idx)) {
1253         mode = get_field(env->hstatus, HSTATUS_SPVP);
1254     } else if (mode == PRV_M && access_type != MMU_INST_FETCH &&
1255                get_field(env->mstatus, MSTATUS_MPRV)) {
1256         mode = get_field(env->mstatus, MSTATUS_MPP);
1257         if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) {
1258             two_stage_lookup = true;
1259         }
1260     }
1261 
1262     pmu_tlb_fill_incr_ctr(cpu, access_type);
1263     if (env->virt_enabled ||
1264         ((mmuidx_2stage(mmu_idx) || two_stage_lookup) &&
1265          access_type != MMU_INST_FETCH)) {
1266         /* Two stage lookup */
1267         ret = get_physical_address(env, &pa, &prot, address,
1268                                    &env->guest_phys_fault_addr, access_type,
1269                                    mmu_idx, true, true, false);
1270 
1271         /*
1272          * A G-stage exception may be triggered during two state lookup.
1273          * And the env->guest_phys_fault_addr has already been set in
1274          * get_physical_address().
1275          */
1276         if (ret == TRANSLATE_G_STAGE_FAIL) {
1277             first_stage_error = false;
1278             two_stage_indirect_error = true;
1279             access_type = MMU_DATA_LOAD;
1280         }
1281 
1282         qemu_log_mask(CPU_LOG_MMU,
1283                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
1284                       HWADDR_FMT_plx " prot %d\n",
1285                       __func__, address, ret, pa, prot);
1286 
1287         if (ret == TRANSLATE_SUCCESS) {
1288             /* Second stage lookup */
1289             im_address = pa;
1290 
1291             ret = get_physical_address(env, &pa, &prot2, im_address, NULL,
1292                                        access_type, mmu_idx, false, true,
1293                                        false);
1294 
1295             qemu_log_mask(CPU_LOG_MMU,
1296                           "%s 2nd-stage address=%" VADDR_PRIx
1297                           " ret %d physical "
1298                           HWADDR_FMT_plx " prot %d\n",
1299                           __func__, im_address, ret, pa, prot2);
1300 
1301             prot &= prot2;
1302 
1303             if (ret == TRANSLATE_SUCCESS) {
1304                 ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1305                                                size, access_type, mode);
1306 
1307                 qemu_log_mask(CPU_LOG_MMU,
1308                               "%s PMP address=" HWADDR_FMT_plx " ret %d prot"
1309                               " %d tlb_size " TARGET_FMT_lu "\n",
1310                               __func__, pa, ret, prot_pmp, tlb_size);
1311 
1312                 prot &= prot_pmp;
1313             }
1314 
1315             if (ret != TRANSLATE_SUCCESS) {
1316                 /*
1317                  * Guest physical address translation failed, this is a HS
1318                  * level exception
1319                  */
1320                 first_stage_error = false;
1321                 env->guest_phys_fault_addr = (im_address |
1322                                               (address &
1323                                                (TARGET_PAGE_SIZE - 1))) >> 2;
1324             }
1325         }
1326     } else {
1327         /* Single stage lookup */
1328         ret = get_physical_address(env, &pa, &prot, address, NULL,
1329                                    access_type, mmu_idx, true, false, false);
1330 
1331         qemu_log_mask(CPU_LOG_MMU,
1332                       "%s address=%" VADDR_PRIx " ret %d physical "
1333                       HWADDR_FMT_plx " prot %d\n",
1334                       __func__, address, ret, pa, prot);
1335 
1336         if (ret == TRANSLATE_SUCCESS) {
1337             ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa,
1338                                            size, access_type, mode);
1339 
1340             qemu_log_mask(CPU_LOG_MMU,
1341                           "%s PMP address=" HWADDR_FMT_plx " ret %d prot"
1342                           " %d tlb_size " TARGET_FMT_lu "\n",
1343                           __func__, pa, ret, prot_pmp, tlb_size);
1344 
1345             prot &= prot_pmp;
1346         }
1347     }
1348 
1349     if (ret == TRANSLATE_PMP_FAIL) {
1350         pmp_violation = true;
1351     }
1352 
1353     if (ret == TRANSLATE_SUCCESS) {
1354         tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
1355                      prot, mmu_idx, tlb_size);
1356         return true;
1357     } else if (probe) {
1358         return false;
1359     } else {
1360         raise_mmu_exception(env, address, access_type, pmp_violation,
1361                             first_stage_error,
1362                             env->virt_enabled || mmuidx_2stage(mmu_idx),
1363                             two_stage_indirect_error);
1364         cpu_loop_exit_restore(cs, retaddr);
1365     }
1366 
1367     return true;
1368 }
1369 
1370 static target_ulong riscv_transformed_insn(CPURISCVState *env,
1371                                            target_ulong insn,
1372                                            target_ulong taddr)
1373 {
1374     target_ulong xinsn = 0;
1375     target_ulong access_rs1 = 0, access_imm = 0, access_size = 0;
1376 
1377     /*
1378      * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
1379      * be uncompressed. The Quadrant 1 of RVC instruction space need
1380      * not be transformed because these instructions won't generate
1381      * any load/store trap.
1382      */
1383 
1384     if ((insn & 0x3) != 0x3) {
1385         /* Transform 16bit instruction into 32bit instruction */
1386         switch (GET_C_OP(insn)) {
1387         case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
1388             switch (GET_C_FUNC(insn)) {
1389             case OPC_RISC_C_FUNC_FLD_LQ:
1390                 if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
1391                     xinsn = OPC_RISC_FLD;
1392                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1393                     access_rs1 = GET_C_RS1S(insn);
1394                     access_imm = GET_C_LD_IMM(insn);
1395                     access_size = 8;
1396                 }
1397                 break;
1398             case OPC_RISC_C_FUNC_LW: /* C.LW */
1399                 xinsn = OPC_RISC_LW;
1400                 xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1401                 access_rs1 = GET_C_RS1S(insn);
1402                 access_imm = GET_C_LW_IMM(insn);
1403                 access_size = 4;
1404                 break;
1405             case OPC_RISC_C_FUNC_FLW_LD:
1406                 if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
1407                     xinsn = OPC_RISC_FLW;
1408                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1409                     access_rs1 = GET_C_RS1S(insn);
1410                     access_imm = GET_C_LW_IMM(insn);
1411                     access_size = 4;
1412                 } else { /* C.LD (RV64/RV128) */
1413                     xinsn = OPC_RISC_LD;
1414                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1415                     access_rs1 = GET_C_RS1S(insn);
1416                     access_imm = GET_C_LD_IMM(insn);
1417                     access_size = 8;
1418                 }
1419                 break;
1420             case OPC_RISC_C_FUNC_FSD_SQ:
1421                 if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
1422                     xinsn = OPC_RISC_FSD;
1423                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1424                     access_rs1 = GET_C_RS1S(insn);
1425                     access_imm = GET_C_SD_IMM(insn);
1426                     access_size = 8;
1427                 }
1428                 break;
1429             case OPC_RISC_C_FUNC_SW: /* C.SW */
1430                 xinsn = OPC_RISC_SW;
1431                 xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1432                 access_rs1 = GET_C_RS1S(insn);
1433                 access_imm = GET_C_SW_IMM(insn);
1434                 access_size = 4;
1435                 break;
1436             case OPC_RISC_C_FUNC_FSW_SD:
1437                 if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
1438                     xinsn = OPC_RISC_FSW;
1439                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1440                     access_rs1 = GET_C_RS1S(insn);
1441                     access_imm = GET_C_SW_IMM(insn);
1442                     access_size = 4;
1443                 } else { /* C.SD (RV64/RV128) */
1444                     xinsn = OPC_RISC_SD;
1445                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1446                     access_rs1 = GET_C_RS1S(insn);
1447                     access_imm = GET_C_SD_IMM(insn);
1448                     access_size = 8;
1449                 }
1450                 break;
1451             default:
1452                 break;
1453             }
1454             break;
1455         case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
1456             switch (GET_C_FUNC(insn)) {
1457             case OPC_RISC_C_FUNC_FLDSP_LQSP:
1458                 if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
1459                     xinsn = OPC_RISC_FLD;
1460                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1461                     access_rs1 = 2;
1462                     access_imm = GET_C_LDSP_IMM(insn);
1463                     access_size = 8;
1464                 }
1465                 break;
1466             case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
1467                 xinsn = OPC_RISC_LW;
1468                 xinsn = SET_RD(xinsn, GET_C_RD(insn));
1469                 access_rs1 = 2;
1470                 access_imm = GET_C_LWSP_IMM(insn);
1471                 access_size = 4;
1472                 break;
1473             case OPC_RISC_C_FUNC_FLWSP_LDSP:
1474                 if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
1475                     xinsn = OPC_RISC_FLW;
1476                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1477                     access_rs1 = 2;
1478                     access_imm = GET_C_LWSP_IMM(insn);
1479                     access_size = 4;
1480                 } else { /* C.LDSP (RV64/RV128) */
1481                     xinsn = OPC_RISC_LD;
1482                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1483                     access_rs1 = 2;
1484                     access_imm = GET_C_LDSP_IMM(insn);
1485                     access_size = 8;
1486                 }
1487                 break;
1488             case OPC_RISC_C_FUNC_FSDSP_SQSP:
1489                 if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
1490                     xinsn = OPC_RISC_FSD;
1491                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1492                     access_rs1 = 2;
1493                     access_imm = GET_C_SDSP_IMM(insn);
1494                     access_size = 8;
1495                 }
1496                 break;
1497             case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
1498                 xinsn = OPC_RISC_SW;
1499                 xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1500                 access_rs1 = 2;
1501                 access_imm = GET_C_SWSP_IMM(insn);
1502                 access_size = 4;
1503                 break;
1504             case 7:
1505                 if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
1506                     xinsn = OPC_RISC_FSW;
1507                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1508                     access_rs1 = 2;
1509                     access_imm = GET_C_SWSP_IMM(insn);
1510                     access_size = 4;
1511                 } else { /* C.SDSP (RV64/RV128) */
1512                     xinsn = OPC_RISC_SD;
1513                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1514                     access_rs1 = 2;
1515                     access_imm = GET_C_SDSP_IMM(insn);
1516                     access_size = 8;
1517                 }
1518                 break;
1519             default:
1520                 break;
1521             }
1522             break;
1523         default:
1524             break;
1525         }
1526 
1527         /*
1528          * Clear Bit1 of transformed instruction to indicate that
1529          * original insruction was a 16bit instruction
1530          */
1531         xinsn &= ~((target_ulong)0x2);
1532     } else {
1533         /* Transform 32bit (or wider) instructions */
1534         switch (MASK_OP_MAJOR(insn)) {
1535         case OPC_RISC_ATOMIC:
1536             xinsn = insn;
1537             access_rs1 = GET_RS1(insn);
1538             access_size = 1 << GET_FUNCT3(insn);
1539             break;
1540         case OPC_RISC_LOAD:
1541         case OPC_RISC_FP_LOAD:
1542             xinsn = SET_I_IMM(insn, 0);
1543             access_rs1 = GET_RS1(insn);
1544             access_imm = GET_IMM(insn);
1545             access_size = 1 << GET_FUNCT3(insn);
1546             break;
1547         case OPC_RISC_STORE:
1548         case OPC_RISC_FP_STORE:
1549             xinsn = SET_S_IMM(insn, 0);
1550             access_rs1 = GET_RS1(insn);
1551             access_imm = GET_STORE_IMM(insn);
1552             access_size = 1 << GET_FUNCT3(insn);
1553             break;
1554         case OPC_RISC_SYSTEM:
1555             if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
1556                 xinsn = insn;
1557                 access_rs1 = GET_RS1(insn);
1558                 access_size = 1 << ((GET_FUNCT7(insn) >> 1) & 0x3);
1559                 access_size = 1 << access_size;
1560             }
1561             break;
1562         default:
1563             break;
1564         }
1565     }
1566 
1567     if (access_size) {
1568         xinsn = SET_RS1(xinsn, (taddr - (env->gpr[access_rs1] + access_imm)) &
1569                                (access_size - 1));
1570     }
1571 
1572     return xinsn;
1573 }
1574 #endif /* !CONFIG_USER_ONLY */
1575 
1576 /*
1577  * Handle Traps
1578  *
1579  * Adapted from Spike's processor_t::take_trap.
1580  *
1581  */
1582 void riscv_cpu_do_interrupt(CPUState *cs)
1583 {
1584 #if !defined(CONFIG_USER_ONLY)
1585 
1586     RISCVCPU *cpu = RISCV_CPU(cs);
1587     CPURISCVState *env = &cpu->env;
1588     bool write_gva = false;
1589     uint64_t s;
1590 
1591     /*
1592      * cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
1593      * so we mask off the MSB and separate into trap type and cause.
1594      */
1595     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
1596     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
1597     uint64_t deleg = async ? env->mideleg : env->medeleg;
1598     target_ulong tval = 0;
1599     target_ulong tinst = 0;
1600     target_ulong htval = 0;
1601     target_ulong mtval2 = 0;
1602 
1603     if  (cause == RISCV_EXCP_SEMIHOST) {
1604         do_common_semihosting(cs);
1605         env->pc += 4;
1606         return;
1607     }
1608 
1609     if (!async) {
1610         /* set tval to badaddr for traps with address information */
1611         switch (cause) {
1612         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
1613         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
1614         case RISCV_EXCP_LOAD_ADDR_MIS:
1615         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
1616         case RISCV_EXCP_LOAD_ACCESS_FAULT:
1617         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
1618         case RISCV_EXCP_LOAD_PAGE_FAULT:
1619         case RISCV_EXCP_STORE_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             } else {
1629                 /*
1630                  * The "Addr. Offset" field in transformed instruction is
1631                  * non-zero only for misaligned access.
1632                  */
1633                 tinst = riscv_transformed_insn(env, env->bins, tval);
1634             }
1635             break;
1636         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
1637         case RISCV_EXCP_INST_ADDR_MIS:
1638         case RISCV_EXCP_INST_ACCESS_FAULT:
1639         case RISCV_EXCP_INST_PAGE_FAULT:
1640             write_gva = env->two_stage_lookup;
1641             tval = env->badaddr;
1642             if (env->two_stage_indirect_lookup) {
1643                 /*
1644                  * special pseudoinstruction for G-stage fault taken while
1645                  * doing VS-stage page table walk.
1646                  */
1647                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1648             }
1649             break;
1650         case RISCV_EXCP_ILLEGAL_INST:
1651         case RISCV_EXCP_VIRT_INSTRUCTION_FAULT:
1652             tval = env->bins;
1653             break;
1654         case RISCV_EXCP_BREAKPOINT:
1655             if (cs->watchpoint_hit) {
1656                 tval = cs->watchpoint_hit->hitaddr;
1657                 cs->watchpoint_hit = NULL;
1658             }
1659             break;
1660         default:
1661             break;
1662         }
1663         /* ecall is dispatched as one cause so translate based on mode */
1664         if (cause == RISCV_EXCP_U_ECALL) {
1665             assert(env->priv <= 3);
1666 
1667             if (env->priv == PRV_M) {
1668                 cause = RISCV_EXCP_M_ECALL;
1669             } else if (env->priv == PRV_S && env->virt_enabled) {
1670                 cause = RISCV_EXCP_VS_ECALL;
1671             } else if (env->priv == PRV_S && !env->virt_enabled) {
1672                 cause = RISCV_EXCP_S_ECALL;
1673             } else if (env->priv == PRV_U) {
1674                 cause = RISCV_EXCP_U_ECALL;
1675             }
1676         }
1677     }
1678 
1679     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
1680                      riscv_cpu_get_trap_name(cause, async));
1681 
1682     qemu_log_mask(CPU_LOG_INT,
1683                   "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", "
1684                   "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n",
1685                   __func__, env->mhartid, async, cause, env->pc, tval,
1686                   riscv_cpu_get_trap_name(cause, async));
1687 
1688     if (env->priv <= PRV_S &&
1689             cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) {
1690         /* handle the trap in S-mode */
1691         if (riscv_has_ext(env, RVH)) {
1692             uint64_t hdeleg = async ? env->hideleg : env->hedeleg;
1693 
1694             if (env->virt_enabled && ((hdeleg >> cause) & 1)) {
1695                 /* Trap to VS mode */
1696                 /*
1697                  * See if we need to adjust cause. Yes if its VS mode interrupt
1698                  * no if hypervisor has delegated one of hs mode's interrupt
1699                  */
1700                 if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
1701                     cause == IRQ_VS_EXT) {
1702                     cause = cause - 1;
1703                 }
1704                 write_gva = false;
1705             } else if (env->virt_enabled) {
1706                 /* Trap into HS mode, from virt */
1707                 riscv_cpu_swap_hypervisor_regs(env);
1708                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
1709                                          env->priv);
1710                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, true);
1711 
1712                 htval = env->guest_phys_fault_addr;
1713 
1714                 riscv_cpu_set_virt_enabled(env, 0);
1715             } else {
1716                 /* Trap into HS mode */
1717                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false);
1718                 htval = env->guest_phys_fault_addr;
1719             }
1720             env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva);
1721         }
1722 
1723         s = env->mstatus;
1724         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
1725         s = set_field(s, MSTATUS_SPP, env->priv);
1726         s = set_field(s, MSTATUS_SIE, 0);
1727         env->mstatus = s;
1728         env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
1729         env->sepc = env->pc;
1730         env->stval = tval;
1731         env->htval = htval;
1732         env->htinst = tinst;
1733         env->pc = (env->stvec >> 2 << 2) +
1734                   ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
1735         riscv_cpu_set_mode(env, PRV_S);
1736     } else {
1737         /* handle the trap in M-mode */
1738         if (riscv_has_ext(env, RVH)) {
1739             if (env->virt_enabled) {
1740                 riscv_cpu_swap_hypervisor_regs(env);
1741             }
1742             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
1743                                      env->virt_enabled);
1744             if (env->virt_enabled && tval) {
1745                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
1746             }
1747 
1748             mtval2 = env->guest_phys_fault_addr;
1749 
1750             /* Trapping to M mode, virt is disabled */
1751             riscv_cpu_set_virt_enabled(env, 0);
1752         }
1753 
1754         s = env->mstatus;
1755         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
1756         s = set_field(s, MSTATUS_MPP, env->priv);
1757         s = set_field(s, MSTATUS_MIE, 0);
1758         env->mstatus = s;
1759         env->mcause = cause | ~(((target_ulong)-1) >> async);
1760         env->mepc = env->pc;
1761         env->mtval = tval;
1762         env->mtval2 = mtval2;
1763         env->mtinst = tinst;
1764         env->pc = (env->mtvec >> 2 << 2) +
1765                   ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
1766         riscv_cpu_set_mode(env, PRV_M);
1767     }
1768 
1769     /*
1770      * NOTE: it is not necessary to yield load reservations here. It is only
1771      * necessary for an SC from "another hart" to cause a load reservation
1772      * to be yielded. Refer to the memory consistency model section of the
1773      * RISC-V ISA Specification.
1774      */
1775 
1776     env->two_stage_lookup = false;
1777     env->two_stage_indirect_lookup = false;
1778 #endif
1779     cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */
1780 }
1781