xref: /openbmc/qemu/target/riscv/csr.c (revision b492a4b8)
1 /*
2  * RISC-V Control and Status Registers.
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 "cpu.h"
23 #include "qemu/main-loop.h"
24 #include "exec/exec-all.h"
25 
26 /* CSR function table */
27 static riscv_csr_operations csr_ops[];
28 
29 /* CSR function table constants */
30 enum {
31     CSR_TABLE_SIZE = 0x1000
32 };
33 
34 /* CSR function table public API */
35 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops)
36 {
37     *ops = csr_ops[csrno & (CSR_TABLE_SIZE - 1)];
38 }
39 
40 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
41 {
42     csr_ops[csrno & (CSR_TABLE_SIZE - 1)] = *ops;
43 }
44 
45 /* Predicates */
46 static int fs(CPURISCVState *env, int csrno)
47 {
48 #if !defined(CONFIG_USER_ONLY)
49     /* loose check condition for fcsr in vector extension */
50     if ((csrno == CSR_FCSR) && (env->misa & RVV)) {
51         return 0;
52     }
53     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
54         return -RISCV_EXCP_ILLEGAL_INST;
55     }
56 #endif
57     return 0;
58 }
59 
60 static int vs(CPURISCVState *env, int csrno)
61 {
62     if (env->misa & RVV) {
63         return 0;
64     }
65     return -1;
66 }
67 
68 static int ctr(CPURISCVState *env, int csrno)
69 {
70 #if !defined(CONFIG_USER_ONLY)
71     CPUState *cs = env_cpu(env);
72     RISCVCPU *cpu = RISCV_CPU(cs);
73 
74     if (!cpu->cfg.ext_counters) {
75         /* The Counters extensions is not enabled */
76         return -RISCV_EXCP_ILLEGAL_INST;
77     }
78 
79     if (riscv_cpu_virt_enabled(env)) {
80         switch (csrno) {
81         case CSR_CYCLE:
82             if (!get_field(env->hcounteren, HCOUNTEREN_CY) &&
83                 get_field(env->mcounteren, HCOUNTEREN_CY)) {
84                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
85             }
86             break;
87         case CSR_TIME:
88             if (!get_field(env->hcounteren, HCOUNTEREN_TM) &&
89                 get_field(env->mcounteren, HCOUNTEREN_TM)) {
90                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
91             }
92             break;
93         case CSR_INSTRET:
94             if (!get_field(env->hcounteren, HCOUNTEREN_IR) &&
95                 get_field(env->mcounteren, HCOUNTEREN_IR)) {
96                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
97             }
98             break;
99         case CSR_HPMCOUNTER3...CSR_HPMCOUNTER31:
100             if (!get_field(env->hcounteren, 1 << (csrno - CSR_HPMCOUNTER3)) &&
101                 get_field(env->mcounteren, 1 << (csrno - CSR_HPMCOUNTER3))) {
102                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
103             }
104             break;
105 #if defined(TARGET_RISCV32)
106         case CSR_CYCLEH:
107             if (!get_field(env->hcounteren, HCOUNTEREN_CY) &&
108                 get_field(env->mcounteren, HCOUNTEREN_CY)) {
109                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
110             }
111             break;
112         case CSR_TIMEH:
113             if (!get_field(env->hcounteren, HCOUNTEREN_TM) &&
114                 get_field(env->mcounteren, HCOUNTEREN_TM)) {
115                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
116             }
117             break;
118         case CSR_INSTRETH:
119             if (!get_field(env->hcounteren, HCOUNTEREN_IR) &&
120                 get_field(env->mcounteren, HCOUNTEREN_IR)) {
121                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
122             }
123             break;
124         case CSR_HPMCOUNTER3H...CSR_HPMCOUNTER31H:
125             if (!get_field(env->hcounteren, 1 << (csrno - CSR_HPMCOUNTER3H)) &&
126                 get_field(env->mcounteren, 1 << (csrno - CSR_HPMCOUNTER3H))) {
127                 return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
128             }
129             break;
130 #endif
131         }
132     }
133 #endif
134     return 0;
135 }
136 
137 #if !defined(CONFIG_USER_ONLY)
138 static int any(CPURISCVState *env, int csrno)
139 {
140     return 0;
141 }
142 
143 static int smode(CPURISCVState *env, int csrno)
144 {
145     return -!riscv_has_ext(env, RVS);
146 }
147 
148 static int hmode(CPURISCVState *env, int csrno)
149 {
150     if (riscv_has_ext(env, RVS) &&
151         riscv_has_ext(env, RVH)) {
152         /* Hypervisor extension is supported */
153         if ((env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
154             env->priv == PRV_M) {
155             return 0;
156         } else {
157             return -RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
158         }
159     }
160 
161     return -RISCV_EXCP_ILLEGAL_INST;
162 }
163 
164 static int pmp(CPURISCVState *env, int csrno)
165 {
166     return -!riscv_feature(env, RISCV_FEATURE_PMP);
167 }
168 #endif
169 
170 /* User Floating-Point CSRs */
171 static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val)
172 {
173 #if !defined(CONFIG_USER_ONLY)
174     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
175         return -RISCV_EXCP_ILLEGAL_INST;
176     }
177 #endif
178     *val = riscv_cpu_get_fflags(env);
179     return 0;
180 }
181 
182 static int write_fflags(CPURISCVState *env, int csrno, target_ulong val)
183 {
184 #if !defined(CONFIG_USER_ONLY)
185     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
186         return -RISCV_EXCP_ILLEGAL_INST;
187     }
188     env->mstatus |= MSTATUS_FS;
189 #endif
190     riscv_cpu_set_fflags(env, val & (FSR_AEXC >> FSR_AEXC_SHIFT));
191     return 0;
192 }
193 
194 static int read_frm(CPURISCVState *env, int csrno, target_ulong *val)
195 {
196 #if !defined(CONFIG_USER_ONLY)
197     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
198         return -RISCV_EXCP_ILLEGAL_INST;
199     }
200 #endif
201     *val = env->frm;
202     return 0;
203 }
204 
205 static int write_frm(CPURISCVState *env, int csrno, target_ulong val)
206 {
207 #if !defined(CONFIG_USER_ONLY)
208     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
209         return -RISCV_EXCP_ILLEGAL_INST;
210     }
211     env->mstatus |= MSTATUS_FS;
212 #endif
213     env->frm = val & (FSR_RD >> FSR_RD_SHIFT);
214     return 0;
215 }
216 
217 static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val)
218 {
219 #if !defined(CONFIG_USER_ONLY)
220     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
221         return -RISCV_EXCP_ILLEGAL_INST;
222     }
223 #endif
224     *val = (riscv_cpu_get_fflags(env) << FSR_AEXC_SHIFT)
225         | (env->frm << FSR_RD_SHIFT);
226     if (vs(env, csrno) >= 0) {
227         *val |= (env->vxrm << FSR_VXRM_SHIFT)
228                 | (env->vxsat << FSR_VXSAT_SHIFT);
229     }
230     return 0;
231 }
232 
233 static int write_fcsr(CPURISCVState *env, int csrno, target_ulong val)
234 {
235 #if !defined(CONFIG_USER_ONLY)
236     if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
237         return -RISCV_EXCP_ILLEGAL_INST;
238     }
239     env->mstatus |= MSTATUS_FS;
240 #endif
241     env->frm = (val & FSR_RD) >> FSR_RD_SHIFT;
242     if (vs(env, csrno) >= 0) {
243         env->vxrm = (val & FSR_VXRM) >> FSR_VXRM_SHIFT;
244         env->vxsat = (val & FSR_VXSAT) >> FSR_VXSAT_SHIFT;
245     }
246     riscv_cpu_set_fflags(env, (val & FSR_AEXC) >> FSR_AEXC_SHIFT);
247     return 0;
248 }
249 
250 static int read_vtype(CPURISCVState *env, int csrno, target_ulong *val)
251 {
252     *val = env->vtype;
253     return 0;
254 }
255 
256 static int read_vl(CPURISCVState *env, int csrno, target_ulong *val)
257 {
258     *val = env->vl;
259     return 0;
260 }
261 
262 static int read_vxrm(CPURISCVState *env, int csrno, target_ulong *val)
263 {
264     *val = env->vxrm;
265     return 0;
266 }
267 
268 static int write_vxrm(CPURISCVState *env, int csrno, target_ulong val)
269 {
270     env->vxrm = val;
271     return 0;
272 }
273 
274 static int read_vxsat(CPURISCVState *env, int csrno, target_ulong *val)
275 {
276     *val = env->vxsat;
277     return 0;
278 }
279 
280 static int write_vxsat(CPURISCVState *env, int csrno, target_ulong val)
281 {
282     env->vxsat = val;
283     return 0;
284 }
285 
286 static int read_vstart(CPURISCVState *env, int csrno, target_ulong *val)
287 {
288     *val = env->vstart;
289     return 0;
290 }
291 
292 static int write_vstart(CPURISCVState *env, int csrno, target_ulong val)
293 {
294     env->vstart = val;
295     return 0;
296 }
297 
298 /* User Timers and Counters */
299 static int read_instret(CPURISCVState *env, int csrno, target_ulong *val)
300 {
301 #if !defined(CONFIG_USER_ONLY)
302     if (icount_enabled()) {
303         *val = icount_get();
304     } else {
305         *val = cpu_get_host_ticks();
306     }
307 #else
308     *val = cpu_get_host_ticks();
309 #endif
310     return 0;
311 }
312 
313 #if defined(TARGET_RISCV32)
314 static int read_instreth(CPURISCVState *env, int csrno, target_ulong *val)
315 {
316 #if !defined(CONFIG_USER_ONLY)
317     if (icount_enabled()) {
318         *val = icount_get() >> 32;
319     } else {
320         *val = cpu_get_host_ticks() >> 32;
321     }
322 #else
323     *val = cpu_get_host_ticks() >> 32;
324 #endif
325     return 0;
326 }
327 #endif /* TARGET_RISCV32 */
328 
329 #if defined(CONFIG_USER_ONLY)
330 static int read_time(CPURISCVState *env, int csrno, target_ulong *val)
331 {
332     *val = cpu_get_host_ticks();
333     return 0;
334 }
335 
336 #if defined(TARGET_RISCV32)
337 static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
338 {
339     *val = cpu_get_host_ticks() >> 32;
340     return 0;
341 }
342 #endif
343 
344 #else /* CONFIG_USER_ONLY */
345 
346 static int read_time(CPURISCVState *env, int csrno, target_ulong *val)
347 {
348     uint64_t delta = riscv_cpu_virt_enabled(env) ? env->htimedelta : 0;
349 
350     if (!env->rdtime_fn) {
351         return -RISCV_EXCP_ILLEGAL_INST;
352     }
353 
354     *val = env->rdtime_fn(env->rdtime_fn_arg) + delta;
355     return 0;
356 }
357 
358 #if defined(TARGET_RISCV32)
359 static int read_timeh(CPURISCVState *env, int csrno, target_ulong *val)
360 {
361     uint64_t delta = riscv_cpu_virt_enabled(env) ? env->htimedelta : 0;
362 
363     if (!env->rdtime_fn) {
364         return -RISCV_EXCP_ILLEGAL_INST;
365     }
366 
367     *val = (env->rdtime_fn(env->rdtime_fn_arg) + delta) >> 32;
368     return 0;
369 }
370 #endif
371 
372 /* Machine constants */
373 
374 #define M_MODE_INTERRUPTS  (MIP_MSIP | MIP_MTIP | MIP_MEIP)
375 #define S_MODE_INTERRUPTS  (MIP_SSIP | MIP_STIP | MIP_SEIP)
376 #define VS_MODE_INTERRUPTS (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP)
377 
378 static const target_ulong delegable_ints = S_MODE_INTERRUPTS |
379                                            VS_MODE_INTERRUPTS;
380 static const target_ulong all_ints = M_MODE_INTERRUPTS | S_MODE_INTERRUPTS |
381                                      VS_MODE_INTERRUPTS;
382 static const target_ulong delegable_excps =
383     (1ULL << (RISCV_EXCP_INST_ADDR_MIS)) |
384     (1ULL << (RISCV_EXCP_INST_ACCESS_FAULT)) |
385     (1ULL << (RISCV_EXCP_ILLEGAL_INST)) |
386     (1ULL << (RISCV_EXCP_BREAKPOINT)) |
387     (1ULL << (RISCV_EXCP_LOAD_ADDR_MIS)) |
388     (1ULL << (RISCV_EXCP_LOAD_ACCESS_FAULT)) |
389     (1ULL << (RISCV_EXCP_STORE_AMO_ADDR_MIS)) |
390     (1ULL << (RISCV_EXCP_STORE_AMO_ACCESS_FAULT)) |
391     (1ULL << (RISCV_EXCP_U_ECALL)) |
392     (1ULL << (RISCV_EXCP_S_ECALL)) |
393     (1ULL << (RISCV_EXCP_VS_ECALL)) |
394     (1ULL << (RISCV_EXCP_M_ECALL)) |
395     (1ULL << (RISCV_EXCP_INST_PAGE_FAULT)) |
396     (1ULL << (RISCV_EXCP_LOAD_PAGE_FAULT)) |
397     (1ULL << (RISCV_EXCP_STORE_PAGE_FAULT)) |
398     (1ULL << (RISCV_EXCP_INST_GUEST_PAGE_FAULT)) |
399     (1ULL << (RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT)) |
400     (1ULL << (RISCV_EXCP_VIRT_INSTRUCTION_FAULT)) |
401     (1ULL << (RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT));
402 static const target_ulong sstatus_v1_10_mask = SSTATUS_SIE | SSTATUS_SPIE |
403     SSTATUS_UIE | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS |
404     SSTATUS_SUM | SSTATUS_MXR | SSTATUS_SD;
405 static const target_ulong sip_writable_mask = SIP_SSIP | MIP_USIP | MIP_UEIP;
406 static const target_ulong hip_writable_mask = MIP_VSSIP | MIP_VSTIP | MIP_VSEIP;
407 static const target_ulong vsip_writable_mask = MIP_VSSIP;
408 
409 #if defined(TARGET_RISCV32)
410 static const char valid_vm_1_10[16] = {
411     [VM_1_10_MBARE] = 1,
412     [VM_1_10_SV32] = 1
413 };
414 #elif defined(TARGET_RISCV64)
415 static const char valid_vm_1_10[16] = {
416     [VM_1_10_MBARE] = 1,
417     [VM_1_10_SV39] = 1,
418     [VM_1_10_SV48] = 1,
419     [VM_1_10_SV57] = 1
420 };
421 #endif /* CONFIG_USER_ONLY */
422 
423 /* Machine Information Registers */
424 static int read_zero(CPURISCVState *env, int csrno, target_ulong *val)
425 {
426     return *val = 0;
427 }
428 
429 static int read_mhartid(CPURISCVState *env, int csrno, target_ulong *val)
430 {
431     *val = env->mhartid;
432     return 0;
433 }
434 
435 /* Machine Trap Setup */
436 static int read_mstatus(CPURISCVState *env, int csrno, target_ulong *val)
437 {
438     *val = env->mstatus;
439     return 0;
440 }
441 
442 static int validate_vm(CPURISCVState *env, target_ulong vm)
443 {
444     return valid_vm_1_10[vm & 0xf];
445 }
446 
447 static int write_mstatus(CPURISCVState *env, int csrno, target_ulong val)
448 {
449     uint64_t mstatus = env->mstatus;
450     uint64_t mask = 0;
451     int dirty;
452 
453     /* flush tlb on mstatus fields that affect VM */
454     if ((val ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP | MSTATUS_MPV |
455             MSTATUS_MPRV | MSTATUS_SUM)) {
456         tlb_flush(env_cpu(env));
457     }
458     mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
459         MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
460         MSTATUS_MPP | MSTATUS_MXR | MSTATUS_TVM | MSTATUS_TSR |
461         MSTATUS_TW;
462 #if defined(TARGET_RISCV64)
463     /*
464      * RV32: MPV and GVA are not in mstatus. The current plan is to
465      * add them to mstatush. For now, we just don't support it.
466      */
467     mask |= MSTATUS_MPV | MSTATUS_GVA;
468 #endif
469 
470     mstatus = (mstatus & ~mask) | (val & mask);
471 
472     dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) |
473             ((mstatus & MSTATUS_XS) == MSTATUS_XS);
474     mstatus = set_field(mstatus, MSTATUS_SD, dirty);
475     env->mstatus = mstatus;
476 
477     return 0;
478 }
479 
480 #ifdef TARGET_RISCV32
481 static int read_mstatush(CPURISCVState *env, int csrno, target_ulong *val)
482 {
483     *val = env->mstatus >> 32;
484     return 0;
485 }
486 
487 static int write_mstatush(CPURISCVState *env, int csrno, target_ulong val)
488 {
489     uint64_t valh = (uint64_t)val << 32;
490     uint64_t mask = MSTATUS_MPV | MSTATUS_GVA;
491 
492     if ((valh ^ env->mstatus) & (MSTATUS_MPV)) {
493         tlb_flush(env_cpu(env));
494     }
495 
496     env->mstatus = (env->mstatus & ~mask) | (valh & mask);
497 
498     return 0;
499 }
500 #endif
501 
502 static int read_misa(CPURISCVState *env, int csrno, target_ulong *val)
503 {
504     *val = env->misa;
505     return 0;
506 }
507 
508 static int write_misa(CPURISCVState *env, int csrno, target_ulong val)
509 {
510     if (!riscv_feature(env, RISCV_FEATURE_MISA)) {
511         /* drop write to misa */
512         return 0;
513     }
514 
515     /* 'I' or 'E' must be present */
516     if (!(val & (RVI | RVE))) {
517         /* It is not, drop write to misa */
518         return 0;
519     }
520 
521     /* 'E' excludes all other extensions */
522     if (val & RVE) {
523         /* when we support 'E' we can do "val = RVE;" however
524          * for now we just drop writes if 'E' is present.
525          */
526         return 0;
527     }
528 
529     /* Mask extensions that are not supported by this hart */
530     val &= env->misa_mask;
531 
532     /* Mask extensions that are not supported by QEMU */
533     val &= (RVI | RVE | RVM | RVA | RVF | RVD | RVC | RVS | RVU);
534 
535     /* 'D' depends on 'F', so clear 'D' if 'F' is not present */
536     if ((val & RVD) && !(val & RVF)) {
537         val &= ~RVD;
538     }
539 
540     /* Suppress 'C' if next instruction is not aligned
541      * TODO: this should check next_pc
542      */
543     if ((val & RVC) && (GETPC() & ~3) != 0) {
544         val &= ~RVC;
545     }
546 
547     /* misa.MXL writes are not supported by QEMU */
548     val = (env->misa & MISA_MXL) | (val & ~MISA_MXL);
549 
550     /* flush translation cache */
551     if (val != env->misa) {
552         tb_flush(env_cpu(env));
553     }
554 
555     env->misa = val;
556 
557     return 0;
558 }
559 
560 static int read_medeleg(CPURISCVState *env, int csrno, target_ulong *val)
561 {
562     *val = env->medeleg;
563     return 0;
564 }
565 
566 static int write_medeleg(CPURISCVState *env, int csrno, target_ulong val)
567 {
568     env->medeleg = (env->medeleg & ~delegable_excps) | (val & delegable_excps);
569     return 0;
570 }
571 
572 static int read_mideleg(CPURISCVState *env, int csrno, target_ulong *val)
573 {
574     *val = env->mideleg;
575     return 0;
576 }
577 
578 static int write_mideleg(CPURISCVState *env, int csrno, target_ulong val)
579 {
580     env->mideleg = (env->mideleg & ~delegable_ints) | (val & delegable_ints);
581     if (riscv_has_ext(env, RVH)) {
582         env->mideleg |= VS_MODE_INTERRUPTS;
583     }
584     return 0;
585 }
586 
587 static int read_mie(CPURISCVState *env, int csrno, target_ulong *val)
588 {
589     *val = env->mie;
590     return 0;
591 }
592 
593 static int write_mie(CPURISCVState *env, int csrno, target_ulong val)
594 {
595     env->mie = (env->mie & ~all_ints) | (val & all_ints);
596     return 0;
597 }
598 
599 static int read_mtvec(CPURISCVState *env, int csrno, target_ulong *val)
600 {
601     *val = env->mtvec;
602     return 0;
603 }
604 
605 static int write_mtvec(CPURISCVState *env, int csrno, target_ulong val)
606 {
607     /* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
608     if ((val & 3) < 2) {
609         env->mtvec = val;
610     } else {
611         qemu_log_mask(LOG_UNIMP, "CSR_MTVEC: reserved mode not supported\n");
612     }
613     return 0;
614 }
615 
616 static int read_mcounteren(CPURISCVState *env, int csrno, target_ulong *val)
617 {
618     *val = env->mcounteren;
619     return 0;
620 }
621 
622 static int write_mcounteren(CPURISCVState *env, int csrno, target_ulong val)
623 {
624     env->mcounteren = val;
625     return 0;
626 }
627 
628 /* This regiser is replaced with CSR_MCOUNTINHIBIT in 1.11.0 */
629 static int read_mscounteren(CPURISCVState *env, int csrno, target_ulong *val)
630 {
631     if (env->priv_ver < PRIV_VERSION_1_11_0) {
632         return -RISCV_EXCP_ILLEGAL_INST;
633     }
634     *val = env->mcounteren;
635     return 0;
636 }
637 
638 /* This regiser is replaced with CSR_MCOUNTINHIBIT in 1.11.0 */
639 static int write_mscounteren(CPURISCVState *env, int csrno, target_ulong val)
640 {
641     if (env->priv_ver < PRIV_VERSION_1_11_0) {
642         return -RISCV_EXCP_ILLEGAL_INST;
643     }
644     env->mcounteren = val;
645     return 0;
646 }
647 
648 /* Machine Trap Handling */
649 static int read_mscratch(CPURISCVState *env, int csrno, target_ulong *val)
650 {
651     *val = env->mscratch;
652     return 0;
653 }
654 
655 static int write_mscratch(CPURISCVState *env, int csrno, target_ulong val)
656 {
657     env->mscratch = val;
658     return 0;
659 }
660 
661 static int read_mepc(CPURISCVState *env, int csrno, target_ulong *val)
662 {
663     *val = env->mepc;
664     return 0;
665 }
666 
667 static int write_mepc(CPURISCVState *env, int csrno, target_ulong val)
668 {
669     env->mepc = val;
670     return 0;
671 }
672 
673 static int read_mcause(CPURISCVState *env, int csrno, target_ulong *val)
674 {
675     *val = env->mcause;
676     return 0;
677 }
678 
679 static int write_mcause(CPURISCVState *env, int csrno, target_ulong val)
680 {
681     env->mcause = val;
682     return 0;
683 }
684 
685 static int read_mbadaddr(CPURISCVState *env, int csrno, target_ulong *val)
686 {
687     *val = env->mbadaddr;
688     return 0;
689 }
690 
691 static int write_mbadaddr(CPURISCVState *env, int csrno, target_ulong val)
692 {
693     env->mbadaddr = val;
694     return 0;
695 }
696 
697 static int rmw_mip(CPURISCVState *env, int csrno, target_ulong *ret_value,
698                    target_ulong new_value, target_ulong write_mask)
699 {
700     RISCVCPU *cpu = env_archcpu(env);
701     /* Allow software control of delegable interrupts not claimed by hardware */
702     target_ulong mask = write_mask & delegable_ints & ~env->miclaim;
703     uint32_t old_mip;
704 
705     if (mask) {
706         old_mip = riscv_cpu_update_mip(cpu, mask, (new_value & mask));
707     } else {
708         old_mip = env->mip;
709     }
710 
711     if (ret_value) {
712         *ret_value = old_mip;
713     }
714 
715     return 0;
716 }
717 
718 /* Supervisor Trap Setup */
719 static int read_sstatus(CPURISCVState *env, int csrno, target_ulong *val)
720 {
721     target_ulong mask = (sstatus_v1_10_mask);
722     *val = env->mstatus & mask;
723     return 0;
724 }
725 
726 static int write_sstatus(CPURISCVState *env, int csrno, target_ulong val)
727 {
728     target_ulong mask = (sstatus_v1_10_mask);
729     target_ulong newval = (env->mstatus & ~mask) | (val & mask);
730     return write_mstatus(env, CSR_MSTATUS, newval);
731 }
732 
733 static int read_sie(CPURISCVState *env, int csrno, target_ulong *val)
734 {
735     if (riscv_cpu_virt_enabled(env)) {
736         /* Tell the guest the VS bits, shifted to the S bit locations */
737         *val = (env->mie & env->mideleg & VS_MODE_INTERRUPTS) >> 1;
738     } else {
739         *val = env->mie & env->mideleg;
740     }
741     return 0;
742 }
743 
744 static int write_sie(CPURISCVState *env, int csrno, target_ulong val)
745 {
746     target_ulong newval;
747 
748     if (riscv_cpu_virt_enabled(env)) {
749         /* Shift the guests S bits to VS */
750         newval = (env->mie & ~VS_MODE_INTERRUPTS) |
751                  ((val << 1) & VS_MODE_INTERRUPTS);
752     } else {
753         newval = (env->mie & ~S_MODE_INTERRUPTS) | (val & S_MODE_INTERRUPTS);
754     }
755 
756     return write_mie(env, CSR_MIE, newval);
757 }
758 
759 static int read_stvec(CPURISCVState *env, int csrno, target_ulong *val)
760 {
761     *val = env->stvec;
762     return 0;
763 }
764 
765 static int write_stvec(CPURISCVState *env, int csrno, target_ulong val)
766 {
767     /* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
768     if ((val & 3) < 2) {
769         env->stvec = val;
770     } else {
771         qemu_log_mask(LOG_UNIMP, "CSR_STVEC: reserved mode not supported\n");
772     }
773     return 0;
774 }
775 
776 static int read_scounteren(CPURISCVState *env, int csrno, target_ulong *val)
777 {
778     *val = env->scounteren;
779     return 0;
780 }
781 
782 static int write_scounteren(CPURISCVState *env, int csrno, target_ulong val)
783 {
784     env->scounteren = val;
785     return 0;
786 }
787 
788 /* Supervisor Trap Handling */
789 static int read_sscratch(CPURISCVState *env, int csrno, target_ulong *val)
790 {
791     *val = env->sscratch;
792     return 0;
793 }
794 
795 static int write_sscratch(CPURISCVState *env, int csrno, target_ulong val)
796 {
797     env->sscratch = val;
798     return 0;
799 }
800 
801 static int read_sepc(CPURISCVState *env, int csrno, target_ulong *val)
802 {
803     *val = env->sepc;
804     return 0;
805 }
806 
807 static int write_sepc(CPURISCVState *env, int csrno, target_ulong val)
808 {
809     env->sepc = val;
810     return 0;
811 }
812 
813 static int read_scause(CPURISCVState *env, int csrno, target_ulong *val)
814 {
815     *val = env->scause;
816     return 0;
817 }
818 
819 static int write_scause(CPURISCVState *env, int csrno, target_ulong val)
820 {
821     env->scause = val;
822     return 0;
823 }
824 
825 static int read_sbadaddr(CPURISCVState *env, int csrno, target_ulong *val)
826 {
827     *val = env->sbadaddr;
828     return 0;
829 }
830 
831 static int write_sbadaddr(CPURISCVState *env, int csrno, target_ulong val)
832 {
833     env->sbadaddr = val;
834     return 0;
835 }
836 
837 static int rmw_sip(CPURISCVState *env, int csrno, target_ulong *ret_value,
838                    target_ulong new_value, target_ulong write_mask)
839 {
840     int ret;
841 
842     if (riscv_cpu_virt_enabled(env)) {
843         /* Shift the new values to line up with the VS bits */
844         ret = rmw_mip(env, CSR_MSTATUS, ret_value, new_value << 1,
845                       (write_mask & sip_writable_mask) << 1 & env->mideleg);
846         ret &= vsip_writable_mask;
847         ret >>= 1;
848     } else {
849         ret = rmw_mip(env, CSR_MSTATUS, ret_value, new_value,
850                       write_mask & env->mideleg & sip_writable_mask);
851     }
852 
853     *ret_value &= env->mideleg;
854     return ret;
855 }
856 
857 /* Supervisor Protection and Translation */
858 static int read_satp(CPURISCVState *env, int csrno, target_ulong *val)
859 {
860     if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
861         *val = 0;
862         return 0;
863     }
864 
865     if (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_TVM)) {
866         return -RISCV_EXCP_ILLEGAL_INST;
867     } else {
868         *val = env->satp;
869     }
870 
871     return 0;
872 }
873 
874 static int write_satp(CPURISCVState *env, int csrno, target_ulong val)
875 {
876     if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
877         return 0;
878     }
879     if (validate_vm(env, get_field(val, SATP_MODE)) &&
880         ((val ^ env->satp) & (SATP_MODE | SATP_ASID | SATP_PPN)))
881     {
882         if (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_TVM)) {
883             return -RISCV_EXCP_ILLEGAL_INST;
884         } else {
885             if ((val ^ env->satp) & SATP_ASID) {
886                 tlb_flush(env_cpu(env));
887             }
888             env->satp = val;
889         }
890     }
891     return 0;
892 }
893 
894 /* Hypervisor Extensions */
895 static int read_hstatus(CPURISCVState *env, int csrno, target_ulong *val)
896 {
897     *val = env->hstatus;
898 #ifdef TARGET_RISCV64
899     /* We only support 64-bit VSXL */
900     *val = set_field(*val, HSTATUS_VSXL, 2);
901 #endif
902     /* We only support little endian */
903     *val = set_field(*val, HSTATUS_VSBE, 0);
904     return 0;
905 }
906 
907 static int write_hstatus(CPURISCVState *env, int csrno, target_ulong val)
908 {
909     env->hstatus = val;
910 #ifdef TARGET_RISCV64
911     if (get_field(val, HSTATUS_VSXL) != 2) {
912         qemu_log_mask(LOG_UNIMP, "QEMU does not support mixed HSXLEN options.");
913     }
914 #endif
915     if (get_field(val, HSTATUS_VSBE) != 0) {
916         qemu_log_mask(LOG_UNIMP, "QEMU does not support big endian guests.");
917     }
918     return 0;
919 }
920 
921 static int read_hedeleg(CPURISCVState *env, int csrno, target_ulong *val)
922 {
923     *val = env->hedeleg;
924     return 0;
925 }
926 
927 static int write_hedeleg(CPURISCVState *env, int csrno, target_ulong val)
928 {
929     env->hedeleg = val;
930     return 0;
931 }
932 
933 static int read_hideleg(CPURISCVState *env, int csrno, target_ulong *val)
934 {
935     *val = env->hideleg;
936     return 0;
937 }
938 
939 static int write_hideleg(CPURISCVState *env, int csrno, target_ulong val)
940 {
941     env->hideleg = val;
942     return 0;
943 }
944 
945 static int rmw_hvip(CPURISCVState *env, int csrno, target_ulong *ret_value,
946                    target_ulong new_value, target_ulong write_mask)
947 {
948     int ret = rmw_mip(env, 0, ret_value, new_value,
949                       write_mask & hip_writable_mask);
950 
951     *ret_value &= hip_writable_mask;
952 
953     return ret;
954 }
955 
956 static int rmw_hip(CPURISCVState *env, int csrno, target_ulong *ret_value,
957                    target_ulong new_value, target_ulong write_mask)
958 {
959     int ret = rmw_mip(env, 0, ret_value, new_value,
960                       write_mask & hip_writable_mask);
961 
962     *ret_value &= hip_writable_mask;
963 
964     return ret;
965 }
966 
967 static int read_hie(CPURISCVState *env, int csrno, target_ulong *val)
968 {
969     *val = env->mie & VS_MODE_INTERRUPTS;
970     return 0;
971 }
972 
973 static int write_hie(CPURISCVState *env, int csrno, target_ulong val)
974 {
975     target_ulong newval = (env->mie & ~VS_MODE_INTERRUPTS) | (val & VS_MODE_INTERRUPTS);
976     return write_mie(env, CSR_MIE, newval);
977 }
978 
979 static int read_hcounteren(CPURISCVState *env, int csrno, target_ulong *val)
980 {
981     *val = env->hcounteren;
982     return 0;
983 }
984 
985 static int write_hcounteren(CPURISCVState *env, int csrno, target_ulong val)
986 {
987     env->hcounteren = val;
988     return 0;
989 }
990 
991 static int read_hgeie(CPURISCVState *env, int csrno, target_ulong *val)
992 {
993     qemu_log_mask(LOG_UNIMP, "No support for a non-zero GEILEN.");
994     return 0;
995 }
996 
997 static int write_hgeie(CPURISCVState *env, int csrno, target_ulong val)
998 {
999     qemu_log_mask(LOG_UNIMP, "No support for a non-zero GEILEN.");
1000     return 0;
1001 }
1002 
1003 static int read_htval(CPURISCVState *env, int csrno, target_ulong *val)
1004 {
1005     *val = env->htval;
1006     return 0;
1007 }
1008 
1009 static int write_htval(CPURISCVState *env, int csrno, target_ulong val)
1010 {
1011     env->htval = val;
1012     return 0;
1013 }
1014 
1015 static int read_htinst(CPURISCVState *env, int csrno, target_ulong *val)
1016 {
1017     *val = env->htinst;
1018     return 0;
1019 }
1020 
1021 static int write_htinst(CPURISCVState *env, int csrno, target_ulong val)
1022 {
1023     return 0;
1024 }
1025 
1026 static int read_hgeip(CPURISCVState *env, int csrno, target_ulong *val)
1027 {
1028     qemu_log_mask(LOG_UNIMP, "No support for a non-zero GEILEN.");
1029     return 0;
1030 }
1031 
1032 static int write_hgeip(CPURISCVState *env, int csrno, target_ulong val)
1033 {
1034     qemu_log_mask(LOG_UNIMP, "No support for a non-zero GEILEN.");
1035     return 0;
1036 }
1037 
1038 static int read_hgatp(CPURISCVState *env, int csrno, target_ulong *val)
1039 {
1040     *val = env->hgatp;
1041     return 0;
1042 }
1043 
1044 static int write_hgatp(CPURISCVState *env, int csrno, target_ulong val)
1045 {
1046     env->hgatp = val;
1047     return 0;
1048 }
1049 
1050 static int read_htimedelta(CPURISCVState *env, int csrno, target_ulong *val)
1051 {
1052     if (!env->rdtime_fn) {
1053         return -RISCV_EXCP_ILLEGAL_INST;
1054     }
1055 
1056 #if defined(TARGET_RISCV32)
1057     *val = env->htimedelta & 0xffffffff;
1058 #else
1059     *val = env->htimedelta;
1060 #endif
1061     return 0;
1062 }
1063 
1064 static int write_htimedelta(CPURISCVState *env, int csrno, target_ulong val)
1065 {
1066     if (!env->rdtime_fn) {
1067         return -RISCV_EXCP_ILLEGAL_INST;
1068     }
1069 
1070 #if defined(TARGET_RISCV32)
1071     env->htimedelta = deposit64(env->htimedelta, 0, 32, (uint64_t)val);
1072 #else
1073     env->htimedelta = val;
1074 #endif
1075     return 0;
1076 }
1077 
1078 #if defined(TARGET_RISCV32)
1079 static int read_htimedeltah(CPURISCVState *env, int csrno, target_ulong *val)
1080 {
1081     if (!env->rdtime_fn) {
1082         return -RISCV_EXCP_ILLEGAL_INST;
1083     }
1084 
1085     *val = env->htimedelta >> 32;
1086     return 0;
1087 }
1088 
1089 static int write_htimedeltah(CPURISCVState *env, int csrno, target_ulong val)
1090 {
1091     if (!env->rdtime_fn) {
1092         return -RISCV_EXCP_ILLEGAL_INST;
1093     }
1094 
1095     env->htimedelta = deposit64(env->htimedelta, 32, 32, (uint64_t)val);
1096     return 0;
1097 }
1098 #endif
1099 
1100 /* Virtual CSR Registers */
1101 static int read_vsstatus(CPURISCVState *env, int csrno, target_ulong *val)
1102 {
1103     *val = env->vsstatus;
1104     return 0;
1105 }
1106 
1107 static int write_vsstatus(CPURISCVState *env, int csrno, target_ulong val)
1108 {
1109     uint64_t mask = (target_ulong)-1;
1110     env->vsstatus = (env->vsstatus & ~mask) | (uint64_t)val;
1111     return 0;
1112 }
1113 
1114 static int rmw_vsip(CPURISCVState *env, int csrno, target_ulong *ret_value,
1115                     target_ulong new_value, target_ulong write_mask)
1116 {
1117     int ret = rmw_mip(env, 0, ret_value, new_value,
1118                       write_mask & env->mideleg & vsip_writable_mask);
1119     return ret;
1120 }
1121 
1122 static int read_vsie(CPURISCVState *env, int csrno, target_ulong *val)
1123 {
1124     *val = env->mie & env->mideleg & VS_MODE_INTERRUPTS;
1125     return 0;
1126 }
1127 
1128 static int write_vsie(CPURISCVState *env, int csrno, target_ulong val)
1129 {
1130     target_ulong newval = (env->mie & ~env->mideleg) | (val & env->mideleg & MIP_VSSIP);
1131     return write_mie(env, CSR_MIE, newval);
1132 }
1133 
1134 static int read_vstvec(CPURISCVState *env, int csrno, target_ulong *val)
1135 {
1136     *val = env->vstvec;
1137     return 0;
1138 }
1139 
1140 static int write_vstvec(CPURISCVState *env, int csrno, target_ulong val)
1141 {
1142     env->vstvec = val;
1143     return 0;
1144 }
1145 
1146 static int read_vsscratch(CPURISCVState *env, int csrno, target_ulong *val)
1147 {
1148     *val = env->vsscratch;
1149     return 0;
1150 }
1151 
1152 static int write_vsscratch(CPURISCVState *env, int csrno, target_ulong val)
1153 {
1154     env->vsscratch = val;
1155     return 0;
1156 }
1157 
1158 static int read_vsepc(CPURISCVState *env, int csrno, target_ulong *val)
1159 {
1160     *val = env->vsepc;
1161     return 0;
1162 }
1163 
1164 static int write_vsepc(CPURISCVState *env, int csrno, target_ulong val)
1165 {
1166     env->vsepc = val;
1167     return 0;
1168 }
1169 
1170 static int read_vscause(CPURISCVState *env, int csrno, target_ulong *val)
1171 {
1172     *val = env->vscause;
1173     return 0;
1174 }
1175 
1176 static int write_vscause(CPURISCVState *env, int csrno, target_ulong val)
1177 {
1178     env->vscause = val;
1179     return 0;
1180 }
1181 
1182 static int read_vstval(CPURISCVState *env, int csrno, target_ulong *val)
1183 {
1184     *val = env->vstval;
1185     return 0;
1186 }
1187 
1188 static int write_vstval(CPURISCVState *env, int csrno, target_ulong val)
1189 {
1190     env->vstval = val;
1191     return 0;
1192 }
1193 
1194 static int read_vsatp(CPURISCVState *env, int csrno, target_ulong *val)
1195 {
1196     *val = env->vsatp;
1197     return 0;
1198 }
1199 
1200 static int write_vsatp(CPURISCVState *env, int csrno, target_ulong val)
1201 {
1202     env->vsatp = val;
1203     return 0;
1204 }
1205 
1206 static int read_mtval2(CPURISCVState *env, int csrno, target_ulong *val)
1207 {
1208     *val = env->mtval2;
1209     return 0;
1210 }
1211 
1212 static int write_mtval2(CPURISCVState *env, int csrno, target_ulong val)
1213 {
1214     env->mtval2 = val;
1215     return 0;
1216 }
1217 
1218 static int read_mtinst(CPURISCVState *env, int csrno, target_ulong *val)
1219 {
1220     *val = env->mtinst;
1221     return 0;
1222 }
1223 
1224 static int write_mtinst(CPURISCVState *env, int csrno, target_ulong val)
1225 {
1226     env->mtinst = val;
1227     return 0;
1228 }
1229 
1230 /* Physical Memory Protection */
1231 static int read_pmpcfg(CPURISCVState *env, int csrno, target_ulong *val)
1232 {
1233     *val = pmpcfg_csr_read(env, csrno - CSR_PMPCFG0);
1234     return 0;
1235 }
1236 
1237 static int write_pmpcfg(CPURISCVState *env, int csrno, target_ulong val)
1238 {
1239     pmpcfg_csr_write(env, csrno - CSR_PMPCFG0, val);
1240     return 0;
1241 }
1242 
1243 static int read_pmpaddr(CPURISCVState *env, int csrno, target_ulong *val)
1244 {
1245     *val = pmpaddr_csr_read(env, csrno - CSR_PMPADDR0);
1246     return 0;
1247 }
1248 
1249 static int write_pmpaddr(CPURISCVState *env, int csrno, target_ulong val)
1250 {
1251     pmpaddr_csr_write(env, csrno - CSR_PMPADDR0, val);
1252     return 0;
1253 }
1254 
1255 #endif
1256 
1257 /*
1258  * riscv_csrrw - read and/or update control and status register
1259  *
1260  * csrr   <->  riscv_csrrw(env, csrno, ret_value, 0, 0);
1261  * csrrw  <->  riscv_csrrw(env, csrno, ret_value, value, -1);
1262  * csrrs  <->  riscv_csrrw(env, csrno, ret_value, -1, value);
1263  * csrrc  <->  riscv_csrrw(env, csrno, ret_value, 0, value);
1264  */
1265 
1266 int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
1267                 target_ulong new_value, target_ulong write_mask)
1268 {
1269     int ret;
1270     target_ulong old_value;
1271     RISCVCPU *cpu = env_archcpu(env);
1272 
1273     /* check privileges and return -1 if check fails */
1274 #if !defined(CONFIG_USER_ONLY)
1275     int effective_priv = env->priv;
1276     int read_only = get_field(csrno, 0xC00) == 3;
1277 
1278     if (riscv_has_ext(env, RVH) &&
1279         env->priv == PRV_S &&
1280         !riscv_cpu_virt_enabled(env)) {
1281         /*
1282          * We are in S mode without virtualisation, therefore we are in HS Mode.
1283          * Add 1 to the effective privledge level to allow us to access the
1284          * Hypervisor CSRs.
1285          */
1286         effective_priv++;
1287     }
1288 
1289     if ((write_mask && read_only) ||
1290         (!env->debugger && (effective_priv < get_field(csrno, 0x300)))) {
1291         return -RISCV_EXCP_ILLEGAL_INST;
1292     }
1293 #endif
1294 
1295     /* ensure the CSR extension is enabled. */
1296     if (!cpu->cfg.ext_icsr) {
1297         return -RISCV_EXCP_ILLEGAL_INST;
1298     }
1299 
1300     /* check predicate */
1301     if (!csr_ops[csrno].predicate) {
1302         return -RISCV_EXCP_ILLEGAL_INST;
1303     }
1304     ret = csr_ops[csrno].predicate(env, csrno);
1305     if (ret < 0) {
1306         return ret;
1307     }
1308 
1309     /* execute combined read/write operation if it exists */
1310     if (csr_ops[csrno].op) {
1311         return csr_ops[csrno].op(env, csrno, ret_value, new_value, write_mask);
1312     }
1313 
1314     /* if no accessor exists then return failure */
1315     if (!csr_ops[csrno].read) {
1316         return -RISCV_EXCP_ILLEGAL_INST;
1317     }
1318 
1319     /* read old value */
1320     ret = csr_ops[csrno].read(env, csrno, &old_value);
1321     if (ret < 0) {
1322         return ret;
1323     }
1324 
1325     /* write value if writable and write mask set, otherwise drop writes */
1326     if (write_mask) {
1327         new_value = (old_value & ~write_mask) | (new_value & write_mask);
1328         if (csr_ops[csrno].write) {
1329             ret = csr_ops[csrno].write(env, csrno, new_value);
1330             if (ret < 0) {
1331                 return ret;
1332             }
1333         }
1334     }
1335 
1336     /* return old value */
1337     if (ret_value) {
1338         *ret_value = old_value;
1339     }
1340 
1341     return 0;
1342 }
1343 
1344 /*
1345  * Debugger support.  If not in user mode, set env->debugger before the
1346  * riscv_csrrw call and clear it after the call.
1347  */
1348 int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
1349                 target_ulong new_value, target_ulong write_mask)
1350 {
1351     int ret;
1352 #if !defined(CONFIG_USER_ONLY)
1353     env->debugger = true;
1354 #endif
1355     ret = riscv_csrrw(env, csrno, ret_value, new_value, write_mask);
1356 #if !defined(CONFIG_USER_ONLY)
1357     env->debugger = false;
1358 #endif
1359     return ret;
1360 }
1361 
1362 /* Control and Status Register function table */
1363 static riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
1364     /* User Floating-Point CSRs */
1365     [CSR_FFLAGS] =              { fs,   read_fflags,      write_fflags      },
1366     [CSR_FRM] =                 { fs,   read_frm,         write_frm         },
1367     [CSR_FCSR] =                { fs,   read_fcsr,        write_fcsr        },
1368     /* Vector CSRs */
1369     [CSR_VSTART] =              { vs,   read_vstart,      write_vstart      },
1370     [CSR_VXSAT] =               { vs,   read_vxsat,       write_vxsat       },
1371     [CSR_VXRM] =                { vs,   read_vxrm,        write_vxrm        },
1372     [CSR_VL] =                  { vs,   read_vl                             },
1373     [CSR_VTYPE] =               { vs,   read_vtype                          },
1374     /* User Timers and Counters */
1375     [CSR_CYCLE] =               { ctr,  read_instret                        },
1376     [CSR_INSTRET] =             { ctr,  read_instret                        },
1377 #if defined(TARGET_RISCV32)
1378     [CSR_CYCLEH] =              { ctr,  read_instreth                       },
1379     [CSR_INSTRETH] =            { ctr,  read_instreth                       },
1380 #endif
1381 
1382     /* In privileged mode, the monitor will have to emulate TIME CSRs only if
1383      * rdtime callback is not provided by machine/platform emulation */
1384     [CSR_TIME] =                { ctr,  read_time                           },
1385 #if defined(TARGET_RISCV32)
1386     [CSR_TIMEH] =               { ctr,  read_timeh                          },
1387 #endif
1388 
1389 #if !defined(CONFIG_USER_ONLY)
1390     /* Machine Timers and Counters */
1391     [CSR_MCYCLE] =              { any,  read_instret                        },
1392     [CSR_MINSTRET] =            { any,  read_instret                        },
1393 #if defined(TARGET_RISCV32)
1394     [CSR_MCYCLEH] =             { any,  read_instreth                       },
1395     [CSR_MINSTRETH] =           { any,  read_instreth                       },
1396 #endif
1397 
1398     /* Machine Information Registers */
1399     [CSR_MVENDORID] =           { any,  read_zero                           },
1400     [CSR_MARCHID] =             { any,  read_zero                           },
1401     [CSR_MIMPID] =              { any,  read_zero                           },
1402     [CSR_MHARTID] =             { any,  read_mhartid                        },
1403 
1404     /* Machine Trap Setup */
1405     [CSR_MSTATUS] =             { any,  read_mstatus,     write_mstatus     },
1406     [CSR_MISA] =                { any,  read_misa,        write_misa        },
1407     [CSR_MIDELEG] =             { any,  read_mideleg,     write_mideleg     },
1408     [CSR_MEDELEG] =             { any,  read_medeleg,     write_medeleg     },
1409     [CSR_MIE] =                 { any,  read_mie,         write_mie         },
1410     [CSR_MTVEC] =               { any,  read_mtvec,       write_mtvec       },
1411     [CSR_MCOUNTEREN] =          { any,  read_mcounteren,  write_mcounteren  },
1412 
1413 #if defined(TARGET_RISCV32)
1414     [CSR_MSTATUSH] =            { any,  read_mstatush,    write_mstatush    },
1415 #endif
1416 
1417     [CSR_MSCOUNTEREN] =         { any,  read_mscounteren, write_mscounteren },
1418 
1419     /* Machine Trap Handling */
1420     [CSR_MSCRATCH] =            { any,  read_mscratch,    write_mscratch    },
1421     [CSR_MEPC] =                { any,  read_mepc,        write_mepc        },
1422     [CSR_MCAUSE] =              { any,  read_mcause,      write_mcause      },
1423     [CSR_MBADADDR] =            { any,  read_mbadaddr,    write_mbadaddr    },
1424     [CSR_MIP] =                 { any,  NULL,     NULL,     rmw_mip         },
1425 
1426     /* Supervisor Trap Setup */
1427     [CSR_SSTATUS] =             { smode, read_sstatus,     write_sstatus     },
1428     [CSR_SIE] =                 { smode, read_sie,         write_sie         },
1429     [CSR_STVEC] =               { smode, read_stvec,       write_stvec       },
1430     [CSR_SCOUNTEREN] =          { smode, read_scounteren,  write_scounteren  },
1431 
1432     /* Supervisor Trap Handling */
1433     [CSR_SSCRATCH] =            { smode, read_sscratch,    write_sscratch    },
1434     [CSR_SEPC] =                { smode, read_sepc,        write_sepc        },
1435     [CSR_SCAUSE] =              { smode, read_scause,      write_scause      },
1436     [CSR_SBADADDR] =            { smode, read_sbadaddr,    write_sbadaddr    },
1437     [CSR_SIP] =                 { smode, NULL,     NULL,     rmw_sip         },
1438 
1439     /* Supervisor Protection and Translation */
1440     [CSR_SATP] =                { smode, read_satp,        write_satp        },
1441 
1442     [CSR_HSTATUS] =             { hmode,   read_hstatus,     write_hstatus    },
1443     [CSR_HEDELEG] =             { hmode,   read_hedeleg,     write_hedeleg    },
1444     [CSR_HIDELEG] =             { hmode,   read_hideleg,     write_hideleg    },
1445     [CSR_HVIP] =                { hmode,   NULL,     NULL,     rmw_hvip       },
1446     [CSR_HIP] =                 { hmode,   NULL,     NULL,     rmw_hip        },
1447     [CSR_HIE] =                 { hmode,   read_hie,         write_hie        },
1448     [CSR_HCOUNTEREN] =          { hmode,   read_hcounteren,  write_hcounteren },
1449     [CSR_HGEIE] =               { hmode,   read_hgeie,       write_hgeie      },
1450     [CSR_HTVAL] =               { hmode,   read_htval,       write_htval      },
1451     [CSR_HTINST] =              { hmode,   read_htinst,      write_htinst     },
1452     [CSR_HGEIP] =               { hmode,   read_hgeip,       write_hgeip      },
1453     [CSR_HGATP] =               { hmode,   read_hgatp,       write_hgatp      },
1454     [CSR_HTIMEDELTA] =          { hmode,   read_htimedelta,  write_htimedelta },
1455 #if defined(TARGET_RISCV32)
1456     [CSR_HTIMEDELTAH] =         { hmode,   read_htimedeltah, write_htimedeltah},
1457 #endif
1458 
1459     [CSR_VSSTATUS] =            { hmode,   read_vsstatus,    write_vsstatus   },
1460     [CSR_VSIP] =                { hmode,   NULL,     NULL,     rmw_vsip       },
1461     [CSR_VSIE] =                { hmode,   read_vsie,        write_vsie       },
1462     [CSR_VSTVEC] =              { hmode,   read_vstvec,      write_vstvec     },
1463     [CSR_VSSCRATCH] =           { hmode,   read_vsscratch,   write_vsscratch  },
1464     [CSR_VSEPC] =               { hmode,   read_vsepc,       write_vsepc      },
1465     [CSR_VSCAUSE] =             { hmode,   read_vscause,     write_vscause    },
1466     [CSR_VSTVAL] =              { hmode,   read_vstval,      write_vstval     },
1467     [CSR_VSATP] =               { hmode,   read_vsatp,       write_vsatp      },
1468 
1469     [CSR_MTVAL2] =              { hmode,   read_mtval2,      write_mtval2     },
1470     [CSR_MTINST] =              { hmode,   read_mtinst,      write_mtinst     },
1471 
1472     /* Physical Memory Protection */
1473     [CSR_PMPCFG0  ... CSR_PMPCFG3]   = { pmp,   read_pmpcfg,  write_pmpcfg   },
1474     [CSR_PMPADDR0 ... CSR_PMPADDR15] = { pmp,   read_pmpaddr, write_pmpaddr  },
1475 
1476     /* Performance Counters */
1477     [CSR_HPMCOUNTER3   ... CSR_HPMCOUNTER31] =    { ctr,  read_zero          },
1478     [CSR_MHPMCOUNTER3  ... CSR_MHPMCOUNTER31] =   { any,  read_zero          },
1479     [CSR_MHPMEVENT3    ... CSR_MHPMEVENT31] =     { any,  read_zero          },
1480 #if defined(TARGET_RISCV32)
1481     [CSR_HPMCOUNTER3H  ... CSR_HPMCOUNTER31H] =   { ctr,  read_zero          },
1482     [CSR_MHPMCOUNTER3H ... CSR_MHPMCOUNTER31H] =  { any,  read_zero          },
1483 #endif
1484 #endif /* !CONFIG_USER_ONLY */
1485 };
1486