xref: /openbmc/qemu/target/riscv/cpu_helper.c (revision 426beec96a54f89fe4fcbf16adaac64810c32ffb)
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 "exec/page-protection.h"
28 #include "instmap.h"
29 #include "tcg/tcg-op.h"
30 #include "hw/core/tcg-cpu-ops.h"
31 #include "trace.h"
32 #include "semihosting/common-semi.h"
33 #include "sysemu/cpu-timers.h"
34 #include "cpu_bits.h"
35 #include "debug.h"
36 #include "tcg/oversized-guest.h"
37 #include "pmp.h"
38 
riscv_env_mmu_index(CPURISCVState * env,bool ifetch)39 int riscv_env_mmu_index(CPURISCVState *env, bool ifetch)
40 {
41 #ifdef CONFIG_USER_ONLY
42     return 0;
43 #else
44     bool virt = env->virt_enabled;
45     int mode = env->priv;
46 
47     /* All priv -> mmu_idx mapping are here */
48     if (!ifetch) {
49         uint64_t status = env->mstatus;
50 
51         if (mode == PRV_M && get_field(status, MSTATUS_MPRV)) {
52             mode = get_field(env->mstatus, MSTATUS_MPP);
53             virt = get_field(env->mstatus, MSTATUS_MPV) &&
54                    (mode != PRV_M);
55             if (virt) {
56                 status = env->vsstatus;
57             }
58         }
59         if (mode == PRV_S && get_field(status, MSTATUS_SUM)) {
60             mode = MMUIdx_S_SUM;
61         }
62     }
63 
64     return mode | (virt ? MMU_2STAGE_BIT : 0);
65 #endif
66 }
67 
cpu_get_fcfien(CPURISCVState * env)68 bool cpu_get_fcfien(CPURISCVState *env)
69 {
70     /* no cfi extension, return false */
71     if (!env_archcpu(env)->cfg.ext_zicfilp) {
72         return false;
73     }
74 
75     switch (env->priv) {
76     case PRV_U:
77         if (riscv_has_ext(env, RVS)) {
78             return env->senvcfg & SENVCFG_LPE;
79         }
80         return env->menvcfg & MENVCFG_LPE;
81 #ifndef CONFIG_USER_ONLY
82     case PRV_S:
83         if (env->virt_enabled) {
84             return env->henvcfg & HENVCFG_LPE;
85         }
86         return env->menvcfg & MENVCFG_LPE;
87     case PRV_M:
88         return env->mseccfg & MSECCFG_MLPE;
89 #endif
90     default:
91         g_assert_not_reached();
92     }
93 }
94 
cpu_get_bcfien(CPURISCVState * env)95 bool cpu_get_bcfien(CPURISCVState *env)
96 {
97     /* no cfi extension, return false */
98     if (!env_archcpu(env)->cfg.ext_zicfiss) {
99         return false;
100     }
101 
102     switch (env->priv) {
103     case PRV_U:
104         /*
105          * If S is not implemented then shadow stack for U can't be turned on
106          * It is checked in `riscv_cpu_validate_set_extensions`, so no need to
107          * check here or assert here
108          */
109         return env->senvcfg & SENVCFG_SSE;
110 #ifndef CONFIG_USER_ONLY
111     case PRV_S:
112         if (env->virt_enabled) {
113             return env->henvcfg & HENVCFG_SSE;
114         }
115         return env->menvcfg & MENVCFG_SSE;
116     case PRV_M: /* M-mode shadow stack is always off */
117         return false;
118 #endif
119     default:
120         g_assert_not_reached();
121     }
122 }
123 
cpu_get_tb_cpu_state(CPURISCVState * env,vaddr * pc,uint64_t * cs_base,uint32_t * pflags)124 void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc,
125                           uint64_t *cs_base, uint32_t *pflags)
126 {
127     RISCVCPU *cpu = env_archcpu(env);
128     RISCVExtStatus fs, vs;
129     uint32_t flags = 0;
130 
131     *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc;
132     *cs_base = 0;
133 
134     if (cpu->cfg.ext_zve32x) {
135         /*
136          * If env->vl equals to VLMAX, we can use generic vector operation
137          * expanders (GVEC) to accerlate the vector operations.
138          * However, as LMUL could be a fractional number. The maximum
139          * vector size can be operated might be less than 8 bytes,
140          * which is not supported by GVEC. So we set vl_eq_vlmax flag to true
141          * only when maxsz >= 8 bytes.
142          */
143 
144         /* lmul encoded as in DisasContext::lmul */
145         int8_t lmul = sextract32(FIELD_EX64(env->vtype, VTYPE, VLMUL), 0, 3);
146         uint32_t vsew = FIELD_EX64(env->vtype, VTYPE, VSEW);
147         uint32_t vlmax = vext_get_vlmax(cpu->cfg.vlenb, vsew, lmul);
148         uint32_t maxsz = vlmax << vsew;
149         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) &&
150                            (maxsz >= 8);
151         flags = FIELD_DP32(flags, TB_FLAGS, VILL, env->vill);
152         flags = FIELD_DP32(flags, TB_FLAGS, SEW, vsew);
153         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
154                            FIELD_EX64(env->vtype, VTYPE, VLMUL));
155         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
156         flags = FIELD_DP32(flags, TB_FLAGS, VTA,
157                            FIELD_EX64(env->vtype, VTYPE, VTA));
158         flags = FIELD_DP32(flags, TB_FLAGS, VMA,
159                            FIELD_EX64(env->vtype, VTYPE, VMA));
160         flags = FIELD_DP32(flags, TB_FLAGS, VSTART_EQ_ZERO, env->vstart == 0);
161     } else {
162         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
163     }
164 
165     if (cpu_get_fcfien(env)) {
166         /*
167          * For Forward CFI, only the expectation of a lpad at
168          * the start of the block is tracked via env->elp. env->elp
169          * is turned on during jalr translation.
170          */
171         flags = FIELD_DP32(flags, TB_FLAGS, FCFI_LP_EXPECTED, env->elp);
172         flags = FIELD_DP32(flags, TB_FLAGS, FCFI_ENABLED, 1);
173     }
174 
175     if (cpu_get_bcfien(env)) {
176         flags = FIELD_DP32(flags, TB_FLAGS, BCFI_ENABLED, 1);
177     }
178 
179 #ifdef CONFIG_USER_ONLY
180     fs = EXT_STATUS_DIRTY;
181     vs = EXT_STATUS_DIRTY;
182 #else
183     flags = FIELD_DP32(flags, TB_FLAGS, PRIV, env->priv);
184 
185     flags |= riscv_env_mmu_index(env, 0);
186     fs = get_field(env->mstatus, MSTATUS_FS);
187     vs = get_field(env->mstatus, MSTATUS_VS);
188 
189     if (env->virt_enabled) {
190         flags = FIELD_DP32(flags, TB_FLAGS, VIRT_ENABLED, 1);
191         /*
192          * Merge DISABLED and !DIRTY states using MIN.
193          * We will set both fields when dirtying.
194          */
195         fs = MIN(fs, get_field(env->mstatus_hs, MSTATUS_FS));
196         vs = MIN(vs, get_field(env->mstatus_hs, MSTATUS_VS));
197     }
198 
199     /* With Zfinx, floating point is enabled/disabled by Smstateen. */
200     if (!riscv_has_ext(env, RVF)) {
201         fs = (smstateen_acc_ok(env, 0, SMSTATEEN0_FCSR) == RISCV_EXCP_NONE)
202              ? EXT_STATUS_DIRTY : EXT_STATUS_DISABLED;
203     }
204 
205     if (cpu->cfg.debug && !icount_enabled()) {
206         flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled);
207     }
208 #endif
209 
210     flags = FIELD_DP32(flags, TB_FLAGS, FS, fs);
211     flags = FIELD_DP32(flags, TB_FLAGS, VS, vs);
212     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
213     flags = FIELD_DP32(flags, TB_FLAGS, AXL, cpu_address_xl(env));
214     if (env->cur_pmmask != 0) {
215         flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
216     }
217     if (env->cur_pmbase != 0) {
218         flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1);
219     }
220 
221     *pflags = flags;
222 }
223 
riscv_cpu_update_mask(CPURISCVState * env)224 void riscv_cpu_update_mask(CPURISCVState *env)
225 {
226     target_ulong mask = 0, base = 0;
227     RISCVMXL xl = env->xl;
228     /*
229      * TODO: Current RVJ spec does not specify
230      * how the extension interacts with XLEN.
231      */
232 #ifndef CONFIG_USER_ONLY
233     int mode = cpu_address_mode(env);
234     xl = cpu_get_xl(env, mode);
235     if (riscv_has_ext(env, RVJ)) {
236         switch (mode) {
237         case PRV_M:
238             if (env->mmte & M_PM_ENABLE) {
239                 mask = env->mpmmask;
240                 base = env->mpmbase;
241             }
242             break;
243         case PRV_S:
244             if (env->mmte & S_PM_ENABLE) {
245                 mask = env->spmmask;
246                 base = env->spmbase;
247             }
248             break;
249         case PRV_U:
250             if (env->mmte & U_PM_ENABLE) {
251                 mask = env->upmmask;
252                 base = env->upmbase;
253             }
254             break;
255         default:
256             g_assert_not_reached();
257         }
258     }
259 #endif
260     if (xl == MXL_RV32) {
261         env->cur_pmmask = mask & UINT32_MAX;
262         env->cur_pmbase = base & UINT32_MAX;
263     } else {
264         env->cur_pmmask = mask;
265         env->cur_pmbase = base;
266     }
267 }
268 
269 #ifndef CONFIG_USER_ONLY
270 
271 /*
272  * The HS-mode is allowed to configure priority only for the
273  * following VS-mode local interrupts:
274  *
275  * 0  (Reserved interrupt, reads as zero)
276  * 1  Supervisor software interrupt
277  * 4  (Reserved interrupt, reads as zero)
278  * 5  Supervisor timer interrupt
279  * 8  (Reserved interrupt, reads as zero)
280  * 13 (Reserved interrupt)
281  * 14 "
282  * 15 "
283  * 16 "
284  * 17 "
285  * 18 "
286  * 19 "
287  * 20 "
288  * 21 "
289  * 22 "
290  * 23 "
291  */
292 
293 static const int hviprio_index2irq[] = {
294     0, 1, 4, 5, 8, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 };
295 static const int hviprio_index2rdzero[] = {
296     1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
297 
riscv_cpu_hviprio_index2irq(int index,int * out_irq,int * out_rdzero)298 int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero)
299 {
300     if (index < 0 || ARRAY_SIZE(hviprio_index2irq) <= index) {
301         return -EINVAL;
302     }
303 
304     if (out_irq) {
305         *out_irq = hviprio_index2irq[index];
306     }
307 
308     if (out_rdzero) {
309         *out_rdzero = hviprio_index2rdzero[index];
310     }
311 
312     return 0;
313 }
314 
315 /*
316  * Default priorities of local interrupts are defined in the
317  * RISC-V Advanced Interrupt Architecture specification.
318  *
319  * ----------------------------------------------------------------
320  *  Default  |
321  *  Priority | Major Interrupt Numbers
322  * ----------------------------------------------------------------
323  *  Highest  | 47, 23, 46, 45, 22, 44,
324  *           | 43, 21, 42, 41, 20, 40
325  *           |
326  *           | 11 (0b),  3 (03),  7 (07)
327  *           |  9 (09),  1 (01),  5 (05)
328  *           | 12 (0c)
329  *           | 10 (0a),  2 (02),  6 (06)
330  *           |
331  *           | 39, 19, 38, 37, 18, 36,
332  *  Lowest   | 35, 17, 34, 33, 16, 32
333  * ----------------------------------------------------------------
334  */
335 static const uint8_t default_iprio[64] = {
336     /* Custom interrupts 48 to 63 */
337     [63] = IPRIO_MMAXIPRIO,
338     [62] = IPRIO_MMAXIPRIO,
339     [61] = IPRIO_MMAXIPRIO,
340     [60] = IPRIO_MMAXIPRIO,
341     [59] = IPRIO_MMAXIPRIO,
342     [58] = IPRIO_MMAXIPRIO,
343     [57] = IPRIO_MMAXIPRIO,
344     [56] = IPRIO_MMAXIPRIO,
345     [55] = IPRIO_MMAXIPRIO,
346     [54] = IPRIO_MMAXIPRIO,
347     [53] = IPRIO_MMAXIPRIO,
348     [52] = IPRIO_MMAXIPRIO,
349     [51] = IPRIO_MMAXIPRIO,
350     [50] = IPRIO_MMAXIPRIO,
351     [49] = IPRIO_MMAXIPRIO,
352     [48] = IPRIO_MMAXIPRIO,
353 
354     /* Custom interrupts 24 to 31 */
355     [31] = IPRIO_MMAXIPRIO,
356     [30] = IPRIO_MMAXIPRIO,
357     [29] = IPRIO_MMAXIPRIO,
358     [28] = IPRIO_MMAXIPRIO,
359     [27] = IPRIO_MMAXIPRIO,
360     [26] = IPRIO_MMAXIPRIO,
361     [25] = IPRIO_MMAXIPRIO,
362     [24] = IPRIO_MMAXIPRIO,
363 
364     [47] = IPRIO_DEFAULT_UPPER,
365     [23] = IPRIO_DEFAULT_UPPER + 1,
366     [46] = IPRIO_DEFAULT_UPPER + 2,
367     [45] = IPRIO_DEFAULT_UPPER + 3,
368     [22] = IPRIO_DEFAULT_UPPER + 4,
369     [44] = IPRIO_DEFAULT_UPPER + 5,
370 
371     [43] = IPRIO_DEFAULT_UPPER + 6,
372     [21] = IPRIO_DEFAULT_UPPER + 7,
373     [42] = IPRIO_DEFAULT_UPPER + 8,
374     [41] = IPRIO_DEFAULT_UPPER + 9,
375     [20] = IPRIO_DEFAULT_UPPER + 10,
376     [40] = IPRIO_DEFAULT_UPPER + 11,
377 
378     [11] = IPRIO_DEFAULT_M,
379     [3]  = IPRIO_DEFAULT_M + 1,
380     [7]  = IPRIO_DEFAULT_M + 2,
381 
382     [9]  = IPRIO_DEFAULT_S,
383     [1]  = IPRIO_DEFAULT_S + 1,
384     [5]  = IPRIO_DEFAULT_S + 2,
385 
386     [12] = IPRIO_DEFAULT_SGEXT,
387 
388     [10] = IPRIO_DEFAULT_VS,
389     [2]  = IPRIO_DEFAULT_VS + 1,
390     [6]  = IPRIO_DEFAULT_VS + 2,
391 
392     [39] = IPRIO_DEFAULT_LOWER,
393     [19] = IPRIO_DEFAULT_LOWER + 1,
394     [38] = IPRIO_DEFAULT_LOWER + 2,
395     [37] = IPRIO_DEFAULT_LOWER + 3,
396     [18] = IPRIO_DEFAULT_LOWER + 4,
397     [36] = IPRIO_DEFAULT_LOWER + 5,
398 
399     [35] = IPRIO_DEFAULT_LOWER + 6,
400     [17] = IPRIO_DEFAULT_LOWER + 7,
401     [34] = IPRIO_DEFAULT_LOWER + 8,
402     [33] = IPRIO_DEFAULT_LOWER + 9,
403     [16] = IPRIO_DEFAULT_LOWER + 10,
404     [32] = IPRIO_DEFAULT_LOWER + 11,
405 };
406 
riscv_cpu_default_priority(int irq)407 uint8_t riscv_cpu_default_priority(int irq)
408 {
409     if (irq < 0 || irq > 63) {
410         return IPRIO_MMAXIPRIO;
411     }
412 
413     return default_iprio[irq] ? default_iprio[irq] : IPRIO_MMAXIPRIO;
414 };
415 
riscv_cpu_pending_to_irq(CPURISCVState * env,int extirq,unsigned int extirq_def_prio,uint64_t pending,uint8_t * iprio)416 static int riscv_cpu_pending_to_irq(CPURISCVState *env,
417                                     int extirq, unsigned int extirq_def_prio,
418                                     uint64_t pending, uint8_t *iprio)
419 {
420     int irq, best_irq = RISCV_EXCP_NONE;
421     unsigned int prio, best_prio = UINT_MAX;
422 
423     if (!pending) {
424         return RISCV_EXCP_NONE;
425     }
426 
427     irq = ctz64(pending);
428     if (!((extirq == IRQ_M_EXT) ? riscv_cpu_cfg(env)->ext_smaia :
429                                   riscv_cpu_cfg(env)->ext_ssaia)) {
430         return irq;
431     }
432 
433     pending = pending >> irq;
434     while (pending) {
435         prio = iprio[irq];
436         if (!prio) {
437             if (irq == extirq) {
438                 prio = extirq_def_prio;
439             } else {
440                 prio = (riscv_cpu_default_priority(irq) < extirq_def_prio) ?
441                        1 : IPRIO_MMAXIPRIO;
442             }
443         }
444         if ((pending & 0x1) && (prio <= best_prio)) {
445             best_irq = irq;
446             best_prio = prio;
447         }
448         irq++;
449         pending = pending >> 1;
450     }
451 
452     return best_irq;
453 }
454 
455 /*
456  * Doesn't report interrupts inserted using mvip from M-mode firmware or
457  * using hvip bits 13:63 from HS-mode. Those are returned in
458  * riscv_cpu_sirq_pending() and riscv_cpu_vsirq_pending().
459  */
riscv_cpu_all_pending(CPURISCVState * env)460 uint64_t riscv_cpu_all_pending(CPURISCVState *env)
461 {
462     uint32_t gein = get_field(env->hstatus, HSTATUS_VGEIN);
463     uint64_t vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
464     uint64_t vstip = (env->vstime_irq) ? MIP_VSTIP : 0;
465 
466     return (env->mip | vsgein | vstip) & env->mie;
467 }
468 
riscv_cpu_mirq_pending(CPURISCVState * env)469 int riscv_cpu_mirq_pending(CPURISCVState *env)
470 {
471     uint64_t irqs = riscv_cpu_all_pending(env) & ~env->mideleg &
472                     ~(MIP_SGEIP | MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
473 
474     return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
475                                     irqs, env->miprio);
476 }
477 
riscv_cpu_sirq_pending(CPURISCVState * env)478 int riscv_cpu_sirq_pending(CPURISCVState *env)
479 {
480     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg &
481                     ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP);
482     uint64_t irqs_f = env->mvip & env->mvien & ~env->mideleg & env->sie;
483 
484     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
485                                     irqs | irqs_f, env->siprio);
486 }
487 
riscv_cpu_vsirq_pending(CPURISCVState * env)488 int riscv_cpu_vsirq_pending(CPURISCVState *env)
489 {
490     uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg & env->hideleg;
491     uint64_t irqs_f_vs = env->hvip & env->hvien & ~env->hideleg & env->vsie;
492     uint64_t vsbits;
493 
494     /* Bring VS-level bits to correct position */
495     vsbits = irqs & VS_MODE_INTERRUPTS;
496     irqs &= ~VS_MODE_INTERRUPTS;
497     irqs |= vsbits >> 1;
498 
499     return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
500                                     (irqs | irqs_f_vs), env->hviprio);
501 }
502 
riscv_cpu_local_irq_pending(CPURISCVState * env)503 static int riscv_cpu_local_irq_pending(CPURISCVState *env)
504 {
505     uint64_t irqs, pending, mie, hsie, vsie, irqs_f, irqs_f_vs;
506     uint64_t vsbits, irq_delegated;
507     int virq;
508 
509     /* Determine interrupt enable state of all privilege modes */
510     if (env->virt_enabled) {
511         mie = 1;
512         hsie = 1;
513         vsie = (env->priv < PRV_S) ||
514                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
515     } else {
516         mie = (env->priv < PRV_M) ||
517               (env->priv == PRV_M && get_field(env->mstatus, MSTATUS_MIE));
518         hsie = (env->priv < PRV_S) ||
519                (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE));
520         vsie = 0;
521     }
522 
523     /* Determine all pending interrupts */
524     pending = riscv_cpu_all_pending(env);
525 
526     /* Check M-mode interrupts */
527     irqs = pending & ~env->mideleg & -mie;
528     if (irqs) {
529         return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M,
530                                         irqs, env->miprio);
531     }
532 
533     /* Check for virtual S-mode interrupts. */
534     irqs_f = env->mvip & (env->mvien & ~env->mideleg) & env->sie;
535 
536     /* Check HS-mode interrupts */
537     irqs =  ((pending & env->mideleg & ~env->hideleg) | irqs_f) & -hsie;
538     if (irqs) {
539         return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
540                                         irqs, env->siprio);
541     }
542 
543     /* Check for virtual VS-mode interrupts. */
544     irqs_f_vs = env->hvip & env->hvien & ~env->hideleg & env->vsie;
545 
546     /* Check VS-mode interrupts */
547     irq_delegated = pending & env->mideleg & env->hideleg;
548 
549     /* Bring VS-level bits to correct position */
550     vsbits = irq_delegated & VS_MODE_INTERRUPTS;
551     irq_delegated &= ~VS_MODE_INTERRUPTS;
552     irq_delegated |= vsbits >> 1;
553 
554     irqs = (irq_delegated | irqs_f_vs) & -vsie;
555     if (irqs) {
556         virq = riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S,
557                                         irqs, env->hviprio);
558         if (virq <= 0 || (virq > 12 && virq <= 63)) {
559             return virq;
560         } else {
561             return virq + 1;
562         }
563     }
564 
565     /* Indicate no pending interrupt */
566     return RISCV_EXCP_NONE;
567 }
568 
riscv_cpu_exec_interrupt(CPUState * cs,int interrupt_request)569 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
570 {
571     if (interrupt_request & CPU_INTERRUPT_HARD) {
572         RISCVCPU *cpu = RISCV_CPU(cs);
573         CPURISCVState *env = &cpu->env;
574         int interruptno = riscv_cpu_local_irq_pending(env);
575         if (interruptno >= 0) {
576             cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno;
577             riscv_cpu_do_interrupt(cs);
578             return true;
579         }
580     }
581     return false;
582 }
583 
584 /* Return true is floating point support is currently enabled */
riscv_cpu_fp_enabled(CPURISCVState * env)585 bool riscv_cpu_fp_enabled(CPURISCVState *env)
586 {
587     if (env->mstatus & MSTATUS_FS) {
588         if (env->virt_enabled && !(env->mstatus_hs & MSTATUS_FS)) {
589             return false;
590         }
591         return true;
592     }
593 
594     return false;
595 }
596 
597 /* Return true is vector support is currently enabled */
riscv_cpu_vector_enabled(CPURISCVState * env)598 bool riscv_cpu_vector_enabled(CPURISCVState *env)
599 {
600     if (env->mstatus & MSTATUS_VS) {
601         if (env->virt_enabled && !(env->mstatus_hs & MSTATUS_VS)) {
602             return false;
603         }
604         return true;
605     }
606 
607     return false;
608 }
609 
riscv_cpu_swap_hypervisor_regs(CPURISCVState * env)610 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env)
611 {
612     uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM |
613                             MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
614                             MSTATUS64_UXL | MSTATUS_VS;
615 
616     if (riscv_has_ext(env, RVF)) {
617         mstatus_mask |= MSTATUS_FS;
618     }
619     bool current_virt = env->virt_enabled;
620 
621     /*
622      * If zicfilp extension available and henvcfg.LPE = 1,
623      * then apply SPELP mask on mstatus
624      */
625     if (env_archcpu(env)->cfg.ext_zicfilp &&
626         get_field(env->henvcfg, HENVCFG_LPE)) {
627         mstatus_mask |= SSTATUS_SPELP;
628     }
629 
630     g_assert(riscv_has_ext(env, RVH));
631 
632     if (current_virt) {
633         /* Current V=1 and we are about to change to V=0 */
634         env->vsstatus = env->mstatus & mstatus_mask;
635         env->mstatus &= ~mstatus_mask;
636         env->mstatus |= env->mstatus_hs;
637 
638         env->vstvec = env->stvec;
639         env->stvec = env->stvec_hs;
640 
641         env->vsscratch = env->sscratch;
642         env->sscratch = env->sscratch_hs;
643 
644         env->vsepc = env->sepc;
645         env->sepc = env->sepc_hs;
646 
647         env->vscause = env->scause;
648         env->scause = env->scause_hs;
649 
650         env->vstval = env->stval;
651         env->stval = env->stval_hs;
652 
653         env->vsatp = env->satp;
654         env->satp = env->satp_hs;
655     } else {
656         /* Current V=0 and we are about to change to V=1 */
657         env->mstatus_hs = env->mstatus & mstatus_mask;
658         env->mstatus &= ~mstatus_mask;
659         env->mstatus |= env->vsstatus;
660 
661         env->stvec_hs = env->stvec;
662         env->stvec = env->vstvec;
663 
664         env->sscratch_hs = env->sscratch;
665         env->sscratch = env->vsscratch;
666 
667         env->sepc_hs = env->sepc;
668         env->sepc = env->vsepc;
669 
670         env->scause_hs = env->scause;
671         env->scause = env->vscause;
672 
673         env->stval_hs = env->stval;
674         env->stval = env->vstval;
675 
676         env->satp_hs = env->satp;
677         env->satp = env->vsatp;
678     }
679 }
680 
riscv_cpu_get_geilen(CPURISCVState * env)681 target_ulong riscv_cpu_get_geilen(CPURISCVState *env)
682 {
683     if (!riscv_has_ext(env, RVH)) {
684         return 0;
685     }
686 
687     return env->geilen;
688 }
689 
riscv_cpu_set_geilen(CPURISCVState * env,target_ulong geilen)690 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen)
691 {
692     if (!riscv_has_ext(env, RVH)) {
693         return;
694     }
695 
696     if (geilen > (TARGET_LONG_BITS - 1)) {
697         return;
698     }
699 
700     env->geilen = geilen;
701 }
702 
riscv_cpu_claim_interrupts(RISCVCPU * cpu,uint64_t interrupts)703 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts)
704 {
705     CPURISCVState *env = &cpu->env;
706     if (env->miclaim & interrupts) {
707         return -1;
708     } else {
709         env->miclaim |= interrupts;
710         return 0;
711     }
712 }
713 
riscv_cpu_interrupt(CPURISCVState * env)714 void riscv_cpu_interrupt(CPURISCVState *env)
715 {
716     uint64_t gein, vsgein = 0, vstip = 0, irqf = 0;
717     CPUState *cs = env_cpu(env);
718 
719     BQL_LOCK_GUARD();
720 
721     if (env->virt_enabled) {
722         gein = get_field(env->hstatus, HSTATUS_VGEIN);
723         vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0;
724         irqf = env->hvien & env->hvip & env->vsie;
725     } else {
726         irqf = env->mvien & env->mvip & env->sie;
727     }
728 
729     vstip = env->vstime_irq ? MIP_VSTIP : 0;
730 
731     if (env->mip | vsgein | vstip | irqf) {
732         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
733     } else {
734         cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
735     }
736 }
737 
riscv_cpu_update_mip(CPURISCVState * env,uint64_t mask,uint64_t value)738 uint64_t riscv_cpu_update_mip(CPURISCVState *env, uint64_t mask, uint64_t value)
739 {
740     uint64_t old = env->mip;
741 
742     /* No need to update mip for VSTIP */
743     mask = ((mask == MIP_VSTIP) && env->vstime_irq) ? 0 : mask;
744 
745     BQL_LOCK_GUARD();
746 
747     env->mip = (env->mip & ~mask) | (value & mask);
748 
749     riscv_cpu_interrupt(env);
750 
751     return old;
752 }
753 
riscv_cpu_set_rdtime_fn(CPURISCVState * env,uint64_t (* fn)(void *),void * arg)754 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void *),
755                              void *arg)
756 {
757     env->rdtime_fn = fn;
758     env->rdtime_fn_arg = arg;
759 }
760 
riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState * env,uint32_t priv,int (* rmw_fn)(void * arg,target_ulong reg,target_ulong * val,target_ulong new_val,target_ulong write_mask),void * rmw_fn_arg)761 void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv,
762                                    int (*rmw_fn)(void *arg,
763                                                  target_ulong reg,
764                                                  target_ulong *val,
765                                                  target_ulong new_val,
766                                                  target_ulong write_mask),
767                                    void *rmw_fn_arg)
768 {
769     if (priv <= PRV_M) {
770         env->aia_ireg_rmw_fn[priv] = rmw_fn;
771         env->aia_ireg_rmw_fn_arg[priv] = rmw_fn_arg;
772     }
773 }
774 
riscv_cpu_set_mode(CPURISCVState * env,target_ulong newpriv,bool virt_en)775 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv, bool virt_en)
776 {
777     g_assert(newpriv <= PRV_M && newpriv != PRV_RESERVED);
778 
779     if (newpriv != env->priv || env->virt_enabled != virt_en) {
780         if (icount_enabled()) {
781             riscv_itrigger_update_priv(env);
782         }
783 
784         riscv_pmu_update_fixed_ctrs(env, newpriv, virt_en);
785     }
786 
787     /* tlb_flush is unnecessary as mode is contained in mmu_idx */
788     env->priv = newpriv;
789     env->xl = cpu_recompute_xl(env);
790     riscv_cpu_update_mask(env);
791 
792     /*
793      * Clear the load reservation - otherwise a reservation placed in one
794      * context/process can be used by another, resulting in an SC succeeding
795      * incorrectly. Version 2.2 of the ISA specification explicitly requires
796      * this behaviour, while later revisions say that the kernel "should" use
797      * an SC instruction to force the yielding of a load reservation on a
798      * preemptive context switch. As a result, do both.
799      */
800     env->load_res = -1;
801 
802     if (riscv_has_ext(env, RVH)) {
803         /* Flush the TLB on all virt mode changes. */
804         if (env->virt_enabled != virt_en) {
805             tlb_flush(env_cpu(env));
806         }
807 
808         env->virt_enabled = virt_en;
809         if (virt_en) {
810             /*
811              * The guest external interrupts from an interrupt controller are
812              * delivered only when the Guest/VM is running (i.e. V=1). This
813              * means any guest external interrupt which is triggered while the
814              * Guest/VM is not running (i.e. V=0) will be missed on QEMU
815              * resulting in guest with sluggish response to serial console
816              * input and other I/O events.
817              *
818              * To solve this, we check and inject interrupt after setting V=1.
819              */
820             riscv_cpu_update_mip(env, 0, 0);
821         }
822     }
823 }
824 
825 /*
826  * get_physical_address_pmp - check PMP permission for this physical address
827  *
828  * Match the PMP region and check permission for this physical address and it's
829  * TLB page. Returns 0 if the permission checking was successful
830  *
831  * @env: CPURISCVState
832  * @prot: The returned protection attributes
833  * @addr: The physical address to be checked permission
834  * @access_type: The type of MMU access
835  * @mode: Indicates current privilege level.
836  */
get_physical_address_pmp(CPURISCVState * env,int * prot,hwaddr addr,int size,MMUAccessType access_type,int mode)837 static int get_physical_address_pmp(CPURISCVState *env, int *prot, hwaddr addr,
838                                     int size, MMUAccessType access_type,
839                                     int mode)
840 {
841     pmp_priv_t pmp_priv;
842     bool pmp_has_privs;
843 
844     if (!riscv_cpu_cfg(env)->pmp) {
845         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
846         return TRANSLATE_SUCCESS;
847     }
848 
849     pmp_has_privs = pmp_hart_has_privs(env, addr, size, 1 << access_type,
850                                        &pmp_priv, mode);
851     if (!pmp_has_privs) {
852         *prot = 0;
853         return TRANSLATE_PMP_FAIL;
854     }
855 
856     *prot = pmp_priv_to_page_prot(pmp_priv);
857 
858     return TRANSLATE_SUCCESS;
859 }
860 
861 /*
862  * get_physical_address - get the physical address for this virtual address
863  *
864  * Do a page table walk to obtain the physical address corresponding to a
865  * virtual address. Returns 0 if the translation was successful
866  *
867  * Adapted from Spike's mmu_t::translate and mmu_t::walk
868  *
869  * @env: CPURISCVState
870  * @physical: This will be set to the calculated physical address
871  * @prot: The returned protection attributes
872  * @addr: The virtual address or guest physical address to be translated
873  * @fault_pte_addr: If not NULL, this will be set to fault pte address
874  *                  when a error occurs on pte address translation.
875  *                  This will already be shifted to match htval.
876  * @access_type: The type of MMU access
877  * @mmu_idx: Indicates current privilege level
878  * @first_stage: Are we in first stage translation?
879  *               Second stage is used for hypervisor guest translation
880  * @two_stage: Are we going to perform two stage translation
881  * @is_debug: Is this access from a debugger or the monitor?
882  */
get_physical_address(CPURISCVState * env,hwaddr * physical,int * ret_prot,vaddr addr,target_ulong * fault_pte_addr,int access_type,int mmu_idx,bool first_stage,bool two_stage,bool is_debug,bool is_probe)883 static int get_physical_address(CPURISCVState *env, hwaddr *physical,
884                                 int *ret_prot, vaddr addr,
885                                 target_ulong *fault_pte_addr,
886                                 int access_type, int mmu_idx,
887                                 bool first_stage, bool two_stage,
888                                 bool is_debug, bool is_probe)
889 {
890     /*
891      * NOTE: the env->pc value visible here will not be
892      * correct, but the value visible to the exception handler
893      * (riscv_cpu_do_interrupt) is correct
894      */
895     MemTxResult res;
896     MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
897     int mode = mmuidx_priv(mmu_idx);
898     bool use_background = false;
899     hwaddr ppn;
900     int napot_bits = 0;
901     target_ulong napot_mask;
902     bool is_sstack_idx = ((mmu_idx & MMU_IDX_SS_WRITE) == MMU_IDX_SS_WRITE);
903     bool sstack_page = false;
904 
905     /*
906      * Check if we should use the background registers for the two
907      * stage translation. We don't need to check if we actually need
908      * two stage translation as that happened before this function
909      * was called. Background registers will be used if the guest has
910      * forced a two stage translation to be on (in HS or M mode).
911      */
912     if (!env->virt_enabled && two_stage) {
913         use_background = true;
914     }
915 
916     if (mode == PRV_M || !riscv_cpu_cfg(env)->mmu) {
917         *physical = addr;
918         *ret_prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
919         return TRANSLATE_SUCCESS;
920     }
921 
922     *ret_prot = 0;
923 
924     hwaddr base;
925     int levels, ptidxbits, ptesize, vm, widened;
926 
927     if (first_stage == true) {
928         if (use_background) {
929             if (riscv_cpu_mxl(env) == MXL_RV32) {
930                 base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT;
931                 vm = get_field(env->vsatp, SATP32_MODE);
932             } else {
933                 base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT;
934                 vm = get_field(env->vsatp, SATP64_MODE);
935             }
936         } else {
937             if (riscv_cpu_mxl(env) == MXL_RV32) {
938                 base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT;
939                 vm = get_field(env->satp, SATP32_MODE);
940             } else {
941                 base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT;
942                 vm = get_field(env->satp, SATP64_MODE);
943             }
944         }
945         widened = 0;
946     } else {
947         if (riscv_cpu_mxl(env) == MXL_RV32) {
948             base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT;
949             vm = get_field(env->hgatp, SATP32_MODE);
950         } else {
951             base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT;
952             vm = get_field(env->hgatp, SATP64_MODE);
953         }
954         widened = 2;
955     }
956 
957     switch (vm) {
958     case VM_1_10_SV32:
959       levels = 2; ptidxbits = 10; ptesize = 4; break;
960     case VM_1_10_SV39:
961       levels = 3; ptidxbits = 9; ptesize = 8; break;
962     case VM_1_10_SV48:
963       levels = 4; ptidxbits = 9; ptesize = 8; break;
964     case VM_1_10_SV57:
965       levels = 5; ptidxbits = 9; ptesize = 8; break;
966     case VM_1_10_MBARE:
967         *physical = addr;
968         *ret_prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
969         return TRANSLATE_SUCCESS;
970     default:
971       g_assert_not_reached();
972     }
973 
974     CPUState *cs = env_cpu(env);
975     int va_bits = PGSHIFT + levels * ptidxbits + widened;
976     int sxlen = 16 << riscv_cpu_sxl(env);
977     int sxlen_bytes = sxlen / 8;
978 
979     if (first_stage == true) {
980         target_ulong mask, masked_msbs;
981 
982         if (sxlen > (va_bits - 1)) {
983             mask = (1L << (sxlen - (va_bits - 1))) - 1;
984         } else {
985             mask = 0;
986         }
987         masked_msbs = (addr >> (va_bits - 1)) & mask;
988 
989         if (masked_msbs != 0 && masked_msbs != mask) {
990             return TRANSLATE_FAIL;
991         }
992     } else {
993         if (vm != VM_1_10_SV32 && addr >> va_bits != 0) {
994             return TRANSLATE_FAIL;
995         }
996     }
997 
998     bool pbmte = env->menvcfg & MENVCFG_PBMTE;
999     bool svade = riscv_cpu_cfg(env)->ext_svade;
1000     bool svadu = riscv_cpu_cfg(env)->ext_svadu;
1001     bool adue = svadu ? env->menvcfg & MENVCFG_ADUE : !svade;
1002 
1003     if (first_stage && two_stage && env->virt_enabled) {
1004         pbmte = pbmte && (env->henvcfg & HENVCFG_PBMTE);
1005         adue = adue && (env->henvcfg & HENVCFG_ADUE);
1006     }
1007 
1008     int ptshift = (levels - 1) * ptidxbits;
1009     target_ulong pte;
1010     hwaddr pte_addr;
1011     int i;
1012 
1013 #if !TCG_OVERSIZED_GUEST
1014 restart:
1015 #endif
1016     for (i = 0; i < levels; i++, ptshift -= ptidxbits) {
1017         target_ulong idx;
1018         if (i == 0) {
1019             idx = (addr >> (PGSHIFT + ptshift)) &
1020                            ((1 << (ptidxbits + widened)) - 1);
1021         } else {
1022             idx = (addr >> (PGSHIFT + ptshift)) &
1023                            ((1 << ptidxbits) - 1);
1024         }
1025 
1026         /* check that physical address of PTE is legal */
1027 
1028         if (two_stage && first_stage) {
1029             int vbase_prot;
1030             hwaddr vbase;
1031 
1032             /* Do the second stage translation on the base PTE address. */
1033             int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
1034                                                  base, NULL, MMU_DATA_LOAD,
1035                                                  MMUIdx_U, false, true,
1036                                                  is_debug, false);
1037 
1038             if (vbase_ret != TRANSLATE_SUCCESS) {
1039                 if (fault_pte_addr) {
1040                     *fault_pte_addr = (base + idx * ptesize) >> 2;
1041                 }
1042                 return TRANSLATE_G_STAGE_FAIL;
1043             }
1044 
1045             pte_addr = vbase + idx * ptesize;
1046         } else {
1047             pte_addr = base + idx * ptesize;
1048         }
1049 
1050         int pmp_prot;
1051         int pmp_ret = get_physical_address_pmp(env, &pmp_prot, pte_addr,
1052                                                sxlen_bytes,
1053                                                MMU_DATA_LOAD, PRV_S);
1054         if (pmp_ret != TRANSLATE_SUCCESS) {
1055             return TRANSLATE_PMP_FAIL;
1056         }
1057 
1058         if (riscv_cpu_mxl(env) == MXL_RV32) {
1059             pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
1060         } else {
1061             pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
1062         }
1063 
1064         if (res != MEMTX_OK) {
1065             return TRANSLATE_FAIL;
1066         }
1067 
1068         if (riscv_cpu_sxl(env) == MXL_RV32) {
1069             ppn = pte >> PTE_PPN_SHIFT;
1070         } else {
1071             if (pte & PTE_RESERVED) {
1072                 return TRANSLATE_FAIL;
1073             }
1074 
1075             if (!pbmte && (pte & PTE_PBMT)) {
1076                 return TRANSLATE_FAIL;
1077             }
1078 
1079             if (!riscv_cpu_cfg(env)->ext_svnapot && (pte & PTE_N)) {
1080                 return TRANSLATE_FAIL;
1081             }
1082 
1083             ppn = (pte & (target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT;
1084         }
1085 
1086         if (!(pte & PTE_V)) {
1087             /* Invalid PTE */
1088             return TRANSLATE_FAIL;
1089         }
1090         if (pte & (PTE_R | PTE_W | PTE_X)) {
1091             goto leaf;
1092         }
1093 
1094         /* Inner PTE, continue walking */
1095         if (pte & (PTE_D | PTE_A | PTE_U | PTE_ATTR)) {
1096             return TRANSLATE_FAIL;
1097         }
1098         base = ppn << PGSHIFT;
1099     }
1100 
1101     /* No leaf pte at any translation level. */
1102     return TRANSLATE_FAIL;
1103 
1104  leaf:
1105     if (ppn & ((1ULL << ptshift) - 1)) {
1106         /* Misaligned PPN */
1107         return TRANSLATE_FAIL;
1108     }
1109     if (!pbmte && (pte & PTE_PBMT)) {
1110         /* Reserved without Svpbmt. */
1111         return TRANSLATE_FAIL;
1112     }
1113 
1114     target_ulong rwx = pte & (PTE_R | PTE_W | PTE_X);
1115     /* Check for reserved combinations of RWX flags. */
1116     switch (rwx) {
1117     case PTE_W | PTE_X:
1118         return TRANSLATE_FAIL;
1119     case PTE_W:
1120         /* if bcfi enabled, PTE_W is not reserved and shadow stack page */
1121         if (cpu_get_bcfien(env) && first_stage) {
1122             sstack_page = true;
1123             /*
1124              * if ss index, read and write allowed. else if not a probe
1125              * then only read allowed
1126              */
1127             rwx = is_sstack_idx ? (PTE_R | PTE_W) : (is_probe ? 0 :  PTE_R);
1128             break;
1129         }
1130         return TRANSLATE_FAIL;
1131     case PTE_R:
1132         /*
1133          * no matter what's the `access_type`, shadow stack access to readonly
1134          * memory are always store page faults. During unwind, loads will be
1135          * promoted as store fault.
1136          */
1137         if (is_sstack_idx) {
1138             return TRANSLATE_FAIL;
1139         }
1140         break;
1141     }
1142 
1143     int prot = 0;
1144     if (rwx & PTE_R) {
1145         prot |= PAGE_READ;
1146     }
1147     if (rwx & PTE_W) {
1148         prot |= PAGE_WRITE;
1149     }
1150     if (rwx & PTE_X) {
1151         bool mxr = false;
1152 
1153         /*
1154          * Use mstatus for first stage or for the second stage without
1155          * virt_enabled (MPRV+MPV)
1156          */
1157         if (first_stage || !env->virt_enabled) {
1158             mxr = get_field(env->mstatus, MSTATUS_MXR);
1159         }
1160 
1161         /* MPRV+MPV case, check VSSTATUS */
1162         if (first_stage && two_stage && !env->virt_enabled) {
1163             mxr |= get_field(env->vsstatus, MSTATUS_MXR);
1164         }
1165 
1166         /*
1167          * Setting MXR at HS-level overrides both VS-stage and G-stage
1168          * execute-only permissions
1169          */
1170         if (env->virt_enabled) {
1171             mxr |= get_field(env->mstatus_hs, MSTATUS_MXR);
1172         }
1173 
1174         if (mxr) {
1175             prot |= PAGE_READ;
1176         }
1177         prot |= PAGE_EXEC;
1178     }
1179 
1180     if (pte & PTE_U) {
1181         if (mode != PRV_U) {
1182             if (!mmuidx_sum(mmu_idx)) {
1183                 return TRANSLATE_FAIL;
1184             }
1185             /* SUM allows only read+write, not execute. */
1186             prot &= PAGE_READ | PAGE_WRITE;
1187         }
1188     } else if (mode != PRV_S) {
1189         /* Supervisor PTE flags when not S mode */
1190         return TRANSLATE_FAIL;
1191     }
1192 
1193     if (!((prot >> access_type) & 1)) {
1194         /*
1195          * Access check failed, access check failures for shadow stack are
1196          * access faults.
1197          */
1198         return sstack_page ? TRANSLATE_PMP_FAIL : TRANSLATE_FAIL;
1199     }
1200 
1201     target_ulong updated_pte = pte;
1202 
1203     /*
1204      * If ADUE is enabled, set accessed and dirty bits.
1205      * Otherwise raise an exception if necessary.
1206      */
1207     if (adue) {
1208         updated_pte |= PTE_A | (access_type == MMU_DATA_STORE ? PTE_D : 0);
1209     } else if (!(pte & PTE_A) ||
1210                (access_type == MMU_DATA_STORE && !(pte & PTE_D))) {
1211         return TRANSLATE_FAIL;
1212     }
1213 
1214     /* Page table updates need to be atomic with MTTCG enabled */
1215     if (updated_pte != pte && !is_debug) {
1216         if (!adue) {
1217             return TRANSLATE_FAIL;
1218         }
1219 
1220         /*
1221          * - if accessed or dirty bits need updating, and the PTE is
1222          *   in RAM, then we do so atomically with a compare and swap.
1223          * - if the PTE is in IO space or ROM, then it can't be updated
1224          *   and we return TRANSLATE_FAIL.
1225          * - if the PTE changed by the time we went to update it, then
1226          *   it is no longer valid and we must re-walk the page table.
1227          */
1228         MemoryRegion *mr;
1229         hwaddr l = sxlen_bytes, addr1;
1230         mr = address_space_translate(cs->as, pte_addr, &addr1, &l,
1231                                      false, MEMTXATTRS_UNSPECIFIED);
1232         if (memory_region_is_ram(mr)) {
1233             target_ulong *pte_pa = qemu_map_ram_ptr(mr->ram_block, addr1);
1234 #if TCG_OVERSIZED_GUEST
1235             /*
1236              * MTTCG is not enabled on oversized TCG guests so
1237              * page table updates do not need to be atomic
1238              */
1239             *pte_pa = pte = updated_pte;
1240 #else
1241             target_ulong old_pte;
1242             if (riscv_cpu_sxl(env) == MXL_RV32) {
1243                 old_pte = qatomic_cmpxchg((uint32_t *)pte_pa, pte, updated_pte);
1244             } else {
1245                 old_pte = qatomic_cmpxchg(pte_pa, pte, updated_pte);
1246             }
1247             if (old_pte != pte) {
1248                 goto restart;
1249             }
1250             pte = updated_pte;
1251 #endif
1252         } else {
1253             /*
1254              * Misconfigured PTE in ROM (AD bits are not preset) or
1255              * PTE is in IO space and can't be updated atomically.
1256              */
1257             return TRANSLATE_FAIL;
1258         }
1259     }
1260 
1261     /* For superpage mappings, make a fake leaf PTE for the TLB's benefit. */
1262     target_ulong vpn = addr >> PGSHIFT;
1263 
1264     if (riscv_cpu_cfg(env)->ext_svnapot && (pte & PTE_N)) {
1265         napot_bits = ctzl(ppn) + 1;
1266         if ((i != (levels - 1)) || (napot_bits != 4)) {
1267             return TRANSLATE_FAIL;
1268         }
1269     }
1270 
1271     napot_mask = (1 << napot_bits) - 1;
1272     *physical = (((ppn & ~napot_mask) | (vpn & napot_mask) |
1273                   (vpn & (((target_ulong)1 << ptshift) - 1))
1274                  ) << PGSHIFT) | (addr & ~TARGET_PAGE_MASK);
1275 
1276     /*
1277      * Remove write permission unless this is a store, or the page is
1278      * already dirty, so that we TLB miss on later writes to update
1279      * the dirty bit.
1280      */
1281     if (access_type != MMU_DATA_STORE && !(pte & PTE_D)) {
1282         prot &= ~PAGE_WRITE;
1283     }
1284     *ret_prot = prot;
1285 
1286     return TRANSLATE_SUCCESS;
1287 }
1288 
raise_mmu_exception(CPURISCVState * env,target_ulong address,MMUAccessType access_type,bool pmp_violation,bool first_stage,bool two_stage,bool two_stage_indirect)1289 static void raise_mmu_exception(CPURISCVState *env, target_ulong address,
1290                                 MMUAccessType access_type, bool pmp_violation,
1291                                 bool first_stage, bool two_stage,
1292                                 bool two_stage_indirect)
1293 {
1294     CPUState *cs = env_cpu(env);
1295 
1296     switch (access_type) {
1297     case MMU_INST_FETCH:
1298         if (pmp_violation) {
1299             cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT;
1300         } else if (env->virt_enabled && !first_stage) {
1301             cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT;
1302         } else {
1303             cs->exception_index = RISCV_EXCP_INST_PAGE_FAULT;
1304         }
1305         break;
1306     case MMU_DATA_LOAD:
1307         if (pmp_violation) {
1308             cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
1309         } else if (two_stage && !first_stage) {
1310             cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT;
1311         } else {
1312             cs->exception_index = RISCV_EXCP_LOAD_PAGE_FAULT;
1313         }
1314         break;
1315     case MMU_DATA_STORE:
1316         if (pmp_violation) {
1317             cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1318         } else if (two_stage && !first_stage) {
1319             cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
1320         } else {
1321             cs->exception_index = RISCV_EXCP_STORE_PAGE_FAULT;
1322         }
1323         break;
1324     default:
1325         g_assert_not_reached();
1326     }
1327     env->badaddr = address;
1328     env->two_stage_lookup = two_stage;
1329     env->two_stage_indirect_lookup = two_stage_indirect;
1330 }
1331 
riscv_cpu_get_phys_page_debug(CPUState * cs,vaddr addr)1332 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
1333 {
1334     RISCVCPU *cpu = RISCV_CPU(cs);
1335     CPURISCVState *env = &cpu->env;
1336     hwaddr phys_addr;
1337     int prot;
1338     int mmu_idx = riscv_env_mmu_index(&cpu->env, false);
1339 
1340     if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx,
1341                              true, env->virt_enabled, true, false)) {
1342         return -1;
1343     }
1344 
1345     if (env->virt_enabled) {
1346         if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL,
1347                                  0, MMUIdx_U, false, true, true, false)) {
1348             return -1;
1349         }
1350     }
1351 
1352     return phys_addr & TARGET_PAGE_MASK;
1353 }
1354 
riscv_cpu_do_transaction_failed(CPUState * cs,hwaddr physaddr,vaddr addr,unsigned size,MMUAccessType access_type,int mmu_idx,MemTxAttrs attrs,MemTxResult response,uintptr_t retaddr)1355 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
1356                                      vaddr addr, unsigned size,
1357                                      MMUAccessType access_type,
1358                                      int mmu_idx, MemTxAttrs attrs,
1359                                      MemTxResult response, uintptr_t retaddr)
1360 {
1361     RISCVCPU *cpu = RISCV_CPU(cs);
1362     CPURISCVState *env = &cpu->env;
1363 
1364     if (access_type == MMU_DATA_STORE) {
1365         cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1366     } else if (access_type == MMU_DATA_LOAD) {
1367         cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
1368     } else {
1369         cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT;
1370     }
1371 
1372     env->badaddr = addr;
1373     env->two_stage_lookup = mmuidx_2stage(mmu_idx);
1374     env->two_stage_indirect_lookup = false;
1375     cpu_loop_exit_restore(cs, retaddr);
1376 }
1377 
riscv_cpu_do_unaligned_access(CPUState * cs,vaddr addr,MMUAccessType access_type,int mmu_idx,uintptr_t retaddr)1378 void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
1379                                    MMUAccessType access_type, int mmu_idx,
1380                                    uintptr_t retaddr)
1381 {
1382     RISCVCPU *cpu = RISCV_CPU(cs);
1383     CPURISCVState *env = &cpu->env;
1384     switch (access_type) {
1385     case MMU_INST_FETCH:
1386         cs->exception_index = RISCV_EXCP_INST_ADDR_MIS;
1387         break;
1388     case MMU_DATA_LOAD:
1389         cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS;
1390         /* shadow stack mis aligned accesses are access faults */
1391         if (mmu_idx & MMU_IDX_SS_WRITE) {
1392             cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT;
1393         }
1394         break;
1395     case MMU_DATA_STORE:
1396         cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS;
1397         /* shadow stack mis aligned accesses are access faults */
1398         if (mmu_idx & MMU_IDX_SS_WRITE) {
1399             cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1400         }
1401         break;
1402     default:
1403         g_assert_not_reached();
1404     }
1405     env->badaddr = addr;
1406     env->two_stage_lookup = mmuidx_2stage(mmu_idx);
1407     env->two_stage_indirect_lookup = false;
1408     cpu_loop_exit_restore(cs, retaddr);
1409 }
1410 
1411 
pmu_tlb_fill_incr_ctr(RISCVCPU * cpu,MMUAccessType access_type)1412 static void pmu_tlb_fill_incr_ctr(RISCVCPU *cpu, MMUAccessType access_type)
1413 {
1414     enum riscv_pmu_event_idx pmu_event_type;
1415 
1416     switch (access_type) {
1417     case MMU_INST_FETCH:
1418         pmu_event_type = RISCV_PMU_EVENT_CACHE_ITLB_PREFETCH_MISS;
1419         break;
1420     case MMU_DATA_LOAD:
1421         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_READ_MISS;
1422         break;
1423     case MMU_DATA_STORE:
1424         pmu_event_type = RISCV_PMU_EVENT_CACHE_DTLB_WRITE_MISS;
1425         break;
1426     default:
1427         return;
1428     }
1429 
1430     riscv_pmu_incr_ctr(cpu, pmu_event_type);
1431 }
1432 
riscv_cpu_tlb_fill(CPUState * cs,vaddr address,int size,MMUAccessType access_type,int mmu_idx,bool probe,uintptr_t retaddr)1433 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
1434                         MMUAccessType access_type, int mmu_idx,
1435                         bool probe, uintptr_t retaddr)
1436 {
1437     RISCVCPU *cpu = RISCV_CPU(cs);
1438     CPURISCVState *env = &cpu->env;
1439     vaddr im_address;
1440     hwaddr pa = 0;
1441     int prot, prot2, prot_pmp;
1442     bool pmp_violation = false;
1443     bool first_stage_error = true;
1444     bool two_stage_lookup = mmuidx_2stage(mmu_idx);
1445     bool two_stage_indirect_error = false;
1446     int ret = TRANSLATE_FAIL;
1447     int mode = mmuidx_priv(mmu_idx);
1448     /* default TLB page size */
1449     hwaddr tlb_size = TARGET_PAGE_SIZE;
1450 
1451     env->guest_phys_fault_addr = 0;
1452 
1453     qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n",
1454                   __func__, address, access_type, mmu_idx);
1455 
1456     pmu_tlb_fill_incr_ctr(cpu, access_type);
1457     if (two_stage_lookup) {
1458         /* Two stage lookup */
1459         ret = get_physical_address(env, &pa, &prot, address,
1460                                    &env->guest_phys_fault_addr, access_type,
1461                                    mmu_idx, true, true, false, probe);
1462 
1463         /*
1464          * A G-stage exception may be triggered during two state lookup.
1465          * And the env->guest_phys_fault_addr has already been set in
1466          * get_physical_address().
1467          */
1468         if (ret == TRANSLATE_G_STAGE_FAIL) {
1469             first_stage_error = false;
1470             two_stage_indirect_error = true;
1471         }
1472 
1473         qemu_log_mask(CPU_LOG_MMU,
1474                       "%s 1st-stage address=%" VADDR_PRIx " ret %d physical "
1475                       HWADDR_FMT_plx " prot %d\n",
1476                       __func__, address, ret, pa, prot);
1477 
1478         if (ret == TRANSLATE_SUCCESS) {
1479             /* Second stage lookup */
1480             im_address = pa;
1481 
1482             ret = get_physical_address(env, &pa, &prot2, im_address, NULL,
1483                                        access_type, MMUIdx_U, false, true,
1484                                        false, probe);
1485 
1486             qemu_log_mask(CPU_LOG_MMU,
1487                           "%s 2nd-stage address=%" VADDR_PRIx
1488                           " ret %d physical "
1489                           HWADDR_FMT_plx " prot %d\n",
1490                           __func__, im_address, ret, pa, prot2);
1491 
1492             prot &= prot2;
1493 
1494             if (ret == TRANSLATE_SUCCESS) {
1495                 ret = get_physical_address_pmp(env, &prot_pmp, pa,
1496                                                size, access_type, mode);
1497                 tlb_size = pmp_get_tlb_size(env, pa);
1498 
1499                 qemu_log_mask(CPU_LOG_MMU,
1500                               "%s PMP address=" HWADDR_FMT_plx " ret %d prot"
1501                               " %d tlb_size %" HWADDR_PRIu "\n",
1502                               __func__, pa, ret, prot_pmp, tlb_size);
1503 
1504                 prot &= prot_pmp;
1505             } else {
1506                 /*
1507                  * Guest physical address translation failed, this is a HS
1508                  * level exception
1509                  */
1510                 first_stage_error = false;
1511                 if (ret != TRANSLATE_PMP_FAIL) {
1512                     env->guest_phys_fault_addr = (im_address |
1513                                                   (address &
1514                                                    (TARGET_PAGE_SIZE - 1))) >> 2;
1515                 }
1516             }
1517         }
1518     } else {
1519         /* Single stage lookup */
1520         ret = get_physical_address(env, &pa, &prot, address, NULL,
1521                                    access_type, mmu_idx, true, false, false,
1522                                    probe);
1523 
1524         qemu_log_mask(CPU_LOG_MMU,
1525                       "%s address=%" VADDR_PRIx " ret %d physical "
1526                       HWADDR_FMT_plx " prot %d\n",
1527                       __func__, address, ret, pa, prot);
1528 
1529         if (ret == TRANSLATE_SUCCESS) {
1530             ret = get_physical_address_pmp(env, &prot_pmp, pa,
1531                                            size, access_type, mode);
1532             tlb_size = pmp_get_tlb_size(env, pa);
1533 
1534             qemu_log_mask(CPU_LOG_MMU,
1535                           "%s PMP address=" HWADDR_FMT_plx " ret %d prot"
1536                           " %d tlb_size %" HWADDR_PRIu "\n",
1537                           __func__, pa, ret, prot_pmp, tlb_size);
1538 
1539             prot &= prot_pmp;
1540         }
1541     }
1542 
1543     if (ret == TRANSLATE_PMP_FAIL) {
1544         pmp_violation = true;
1545     }
1546 
1547     if (ret == TRANSLATE_SUCCESS) {
1548         tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1),
1549                      prot, mmu_idx, tlb_size);
1550         return true;
1551     } else if (probe) {
1552         return false;
1553     } else {
1554         int wp_access = 0;
1555 
1556         if (access_type == MMU_DATA_LOAD) {
1557             wp_access |= BP_MEM_READ;
1558         } else if (access_type == MMU_DATA_STORE) {
1559             wp_access |= BP_MEM_WRITE;
1560         }
1561 
1562         /*
1563          * If a watchpoint isn't found for 'addr' this will
1564          * be a no-op and we'll resume the mmu_exception path.
1565          * Otherwise we'll throw a debug exception and execution
1566          * will continue elsewhere.
1567          */
1568         cpu_check_watchpoint(cs, address, size, MEMTXATTRS_UNSPECIFIED,
1569                              wp_access, retaddr);
1570 
1571         raise_mmu_exception(env, address, access_type, pmp_violation,
1572                             first_stage_error, two_stage_lookup,
1573                             two_stage_indirect_error);
1574         cpu_loop_exit_restore(cs, retaddr);
1575     }
1576 
1577     return true;
1578 }
1579 
riscv_transformed_insn(CPURISCVState * env,target_ulong insn,target_ulong taddr)1580 static target_ulong riscv_transformed_insn(CPURISCVState *env,
1581                                            target_ulong insn,
1582                                            target_ulong taddr)
1583 {
1584     target_ulong xinsn = 0;
1585     target_ulong access_rs1 = 0, access_imm = 0, access_size = 0;
1586 
1587     /*
1588      * Only Quadrant 0 and Quadrant 2 of RVC instruction space need to
1589      * be uncompressed. The Quadrant 1 of RVC instruction space need
1590      * not be transformed because these instructions won't generate
1591      * any load/store trap.
1592      */
1593 
1594     if ((insn & 0x3) != 0x3) {
1595         /* Transform 16bit instruction into 32bit instruction */
1596         switch (GET_C_OP(insn)) {
1597         case OPC_RISC_C_OP_QUAD0: /* Quadrant 0 */
1598             switch (GET_C_FUNC(insn)) {
1599             case OPC_RISC_C_FUNC_FLD_LQ:
1600                 if (riscv_cpu_xlen(env) != 128) { /* C.FLD (RV32/64) */
1601                     xinsn = OPC_RISC_FLD;
1602                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1603                     access_rs1 = GET_C_RS1S(insn);
1604                     access_imm = GET_C_LD_IMM(insn);
1605                     access_size = 8;
1606                 }
1607                 break;
1608             case OPC_RISC_C_FUNC_LW: /* C.LW */
1609                 xinsn = OPC_RISC_LW;
1610                 xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1611                 access_rs1 = GET_C_RS1S(insn);
1612                 access_imm = GET_C_LW_IMM(insn);
1613                 access_size = 4;
1614                 break;
1615             case OPC_RISC_C_FUNC_FLW_LD:
1616                 if (riscv_cpu_xlen(env) == 32) { /* C.FLW (RV32) */
1617                     xinsn = OPC_RISC_FLW;
1618                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1619                     access_rs1 = GET_C_RS1S(insn);
1620                     access_imm = GET_C_LW_IMM(insn);
1621                     access_size = 4;
1622                 } else { /* C.LD (RV64/RV128) */
1623                     xinsn = OPC_RISC_LD;
1624                     xinsn = SET_RD(xinsn, GET_C_RS2S(insn));
1625                     access_rs1 = GET_C_RS1S(insn);
1626                     access_imm = GET_C_LD_IMM(insn);
1627                     access_size = 8;
1628                 }
1629                 break;
1630             case OPC_RISC_C_FUNC_FSD_SQ:
1631                 if (riscv_cpu_xlen(env) != 128) { /* C.FSD (RV32/64) */
1632                     xinsn = OPC_RISC_FSD;
1633                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1634                     access_rs1 = GET_C_RS1S(insn);
1635                     access_imm = GET_C_SD_IMM(insn);
1636                     access_size = 8;
1637                 }
1638                 break;
1639             case OPC_RISC_C_FUNC_SW: /* C.SW */
1640                 xinsn = OPC_RISC_SW;
1641                 xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1642                 access_rs1 = GET_C_RS1S(insn);
1643                 access_imm = GET_C_SW_IMM(insn);
1644                 access_size = 4;
1645                 break;
1646             case OPC_RISC_C_FUNC_FSW_SD:
1647                 if (riscv_cpu_xlen(env) == 32) { /* C.FSW (RV32) */
1648                     xinsn = OPC_RISC_FSW;
1649                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1650                     access_rs1 = GET_C_RS1S(insn);
1651                     access_imm = GET_C_SW_IMM(insn);
1652                     access_size = 4;
1653                 } else { /* C.SD (RV64/RV128) */
1654                     xinsn = OPC_RISC_SD;
1655                     xinsn = SET_RS2(xinsn, GET_C_RS2S(insn));
1656                     access_rs1 = GET_C_RS1S(insn);
1657                     access_imm = GET_C_SD_IMM(insn);
1658                     access_size = 8;
1659                 }
1660                 break;
1661             default:
1662                 break;
1663             }
1664             break;
1665         case OPC_RISC_C_OP_QUAD2: /* Quadrant 2 */
1666             switch (GET_C_FUNC(insn)) {
1667             case OPC_RISC_C_FUNC_FLDSP_LQSP:
1668                 if (riscv_cpu_xlen(env) != 128) { /* C.FLDSP (RV32/64) */
1669                     xinsn = OPC_RISC_FLD;
1670                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1671                     access_rs1 = 2;
1672                     access_imm = GET_C_LDSP_IMM(insn);
1673                     access_size = 8;
1674                 }
1675                 break;
1676             case OPC_RISC_C_FUNC_LWSP: /* C.LWSP */
1677                 xinsn = OPC_RISC_LW;
1678                 xinsn = SET_RD(xinsn, GET_C_RD(insn));
1679                 access_rs1 = 2;
1680                 access_imm = GET_C_LWSP_IMM(insn);
1681                 access_size = 4;
1682                 break;
1683             case OPC_RISC_C_FUNC_FLWSP_LDSP:
1684                 if (riscv_cpu_xlen(env) == 32) { /* C.FLWSP (RV32) */
1685                     xinsn = OPC_RISC_FLW;
1686                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1687                     access_rs1 = 2;
1688                     access_imm = GET_C_LWSP_IMM(insn);
1689                     access_size = 4;
1690                 } else { /* C.LDSP (RV64/RV128) */
1691                     xinsn = OPC_RISC_LD;
1692                     xinsn = SET_RD(xinsn, GET_C_RD(insn));
1693                     access_rs1 = 2;
1694                     access_imm = GET_C_LDSP_IMM(insn);
1695                     access_size = 8;
1696                 }
1697                 break;
1698             case OPC_RISC_C_FUNC_FSDSP_SQSP:
1699                 if (riscv_cpu_xlen(env) != 128) { /* C.FSDSP (RV32/64) */
1700                     xinsn = OPC_RISC_FSD;
1701                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1702                     access_rs1 = 2;
1703                     access_imm = GET_C_SDSP_IMM(insn);
1704                     access_size = 8;
1705                 }
1706                 break;
1707             case OPC_RISC_C_FUNC_SWSP: /* C.SWSP */
1708                 xinsn = OPC_RISC_SW;
1709                 xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1710                 access_rs1 = 2;
1711                 access_imm = GET_C_SWSP_IMM(insn);
1712                 access_size = 4;
1713                 break;
1714             case 7:
1715                 if (riscv_cpu_xlen(env) == 32) { /* C.FSWSP (RV32) */
1716                     xinsn = OPC_RISC_FSW;
1717                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1718                     access_rs1 = 2;
1719                     access_imm = GET_C_SWSP_IMM(insn);
1720                     access_size = 4;
1721                 } else { /* C.SDSP (RV64/RV128) */
1722                     xinsn = OPC_RISC_SD;
1723                     xinsn = SET_RS2(xinsn, GET_C_RS2(insn));
1724                     access_rs1 = 2;
1725                     access_imm = GET_C_SDSP_IMM(insn);
1726                     access_size = 8;
1727                 }
1728                 break;
1729             default:
1730                 break;
1731             }
1732             break;
1733         default:
1734             break;
1735         }
1736 
1737         /*
1738          * Clear Bit1 of transformed instruction to indicate that
1739          * original insruction was a 16bit instruction
1740          */
1741         xinsn &= ~((target_ulong)0x2);
1742     } else {
1743         /* Transform 32bit (or wider) instructions */
1744         switch (MASK_OP_MAJOR(insn)) {
1745         case OPC_RISC_ATOMIC:
1746             xinsn = insn;
1747             access_rs1 = GET_RS1(insn);
1748             access_size = 1 << GET_FUNCT3(insn);
1749             break;
1750         case OPC_RISC_LOAD:
1751         case OPC_RISC_FP_LOAD:
1752             xinsn = SET_I_IMM(insn, 0);
1753             access_rs1 = GET_RS1(insn);
1754             access_imm = GET_IMM(insn);
1755             access_size = 1 << GET_FUNCT3(insn);
1756             break;
1757         case OPC_RISC_STORE:
1758         case OPC_RISC_FP_STORE:
1759             xinsn = SET_S_IMM(insn, 0);
1760             access_rs1 = GET_RS1(insn);
1761             access_imm = GET_STORE_IMM(insn);
1762             access_size = 1 << GET_FUNCT3(insn);
1763             break;
1764         case OPC_RISC_SYSTEM:
1765             if (MASK_OP_SYSTEM(insn) == OPC_RISC_HLVHSV) {
1766                 xinsn = insn;
1767                 access_rs1 = GET_RS1(insn);
1768                 access_size = 1 << ((GET_FUNCT7(insn) >> 1) & 0x3);
1769                 access_size = 1 << access_size;
1770             }
1771             break;
1772         default:
1773             break;
1774         }
1775     }
1776 
1777     if (access_size) {
1778         xinsn = SET_RS1(xinsn, (taddr - (env->gpr[access_rs1] + access_imm)) &
1779                                (access_size - 1));
1780     }
1781 
1782     return xinsn;
1783 }
1784 
promote_load_fault(target_ulong orig_cause)1785 static target_ulong promote_load_fault(target_ulong orig_cause)
1786 {
1787     switch (orig_cause) {
1788     case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
1789         return RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT;
1790 
1791     case RISCV_EXCP_LOAD_ACCESS_FAULT:
1792         return RISCV_EXCP_STORE_AMO_ACCESS_FAULT;
1793 
1794     case RISCV_EXCP_LOAD_PAGE_FAULT:
1795         return RISCV_EXCP_STORE_PAGE_FAULT;
1796     }
1797 
1798     /* if no promotion, return original cause */
1799     return orig_cause;
1800 }
1801 /*
1802  * Handle Traps
1803  *
1804  * Adapted from Spike's processor_t::take_trap.
1805  *
1806  */
riscv_cpu_do_interrupt(CPUState * cs)1807 void riscv_cpu_do_interrupt(CPUState *cs)
1808 {
1809     RISCVCPU *cpu = RISCV_CPU(cs);
1810     CPURISCVState *env = &cpu->env;
1811     bool virt = env->virt_enabled;
1812     bool write_gva = false;
1813     bool always_storeamo = (env->excp_uw2 & RISCV_UW2_ALWAYS_STORE_AMO);
1814     uint64_t s;
1815 
1816     /*
1817      * cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide
1818      * so we mask off the MSB and separate into trap type and cause.
1819      */
1820     bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG);
1821     target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK;
1822     uint64_t deleg = async ? env->mideleg : env->medeleg;
1823     bool s_injected = env->mvip & (1ULL << cause) & env->mvien &&
1824         !(env->mip & (1ULL << cause));
1825     bool vs_injected = env->hvip & (1ULL << cause) & env->hvien &&
1826         !(env->mip & (1ULL << cause));
1827     target_ulong tval = 0;
1828     target_ulong tinst = 0;
1829     target_ulong htval = 0;
1830     target_ulong mtval2 = 0;
1831     int sxlen = 0;
1832     int mxlen = 0;
1833 
1834     if (!async) {
1835         /* set tval to badaddr for traps with address information */
1836         switch (cause) {
1837 #ifdef CONFIG_TCG
1838         case RISCV_EXCP_SEMIHOST:
1839             do_common_semihosting(cs);
1840             env->pc += 4;
1841             return;
1842 #endif
1843         case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT:
1844         case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT:
1845         case RISCV_EXCP_LOAD_ADDR_MIS:
1846         case RISCV_EXCP_STORE_AMO_ADDR_MIS:
1847         case RISCV_EXCP_LOAD_ACCESS_FAULT:
1848         case RISCV_EXCP_STORE_AMO_ACCESS_FAULT:
1849         case RISCV_EXCP_LOAD_PAGE_FAULT:
1850         case RISCV_EXCP_STORE_PAGE_FAULT:
1851             if (always_storeamo) {
1852                 cause = promote_load_fault(cause);
1853             }
1854             write_gva = env->two_stage_lookup;
1855             tval = env->badaddr;
1856             if (env->two_stage_indirect_lookup) {
1857                 /*
1858                  * special pseudoinstruction for G-stage fault taken while
1859                  * doing VS-stage page table walk.
1860                  */
1861                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1862             } else {
1863                 /*
1864                  * The "Addr. Offset" field in transformed instruction is
1865                  * non-zero only for misaligned access.
1866                  */
1867                 tinst = riscv_transformed_insn(env, env->bins, tval);
1868             }
1869             break;
1870         case RISCV_EXCP_INST_GUEST_PAGE_FAULT:
1871         case RISCV_EXCP_INST_ADDR_MIS:
1872         case RISCV_EXCP_INST_ACCESS_FAULT:
1873         case RISCV_EXCP_INST_PAGE_FAULT:
1874             write_gva = env->two_stage_lookup;
1875             tval = env->badaddr;
1876             if (env->two_stage_indirect_lookup) {
1877                 /*
1878                  * special pseudoinstruction for G-stage fault taken while
1879                  * doing VS-stage page table walk.
1880                  */
1881                 tinst = (riscv_cpu_xlen(env) == 32) ? 0x00002000 : 0x00003000;
1882             }
1883             break;
1884         case RISCV_EXCP_ILLEGAL_INST:
1885         case RISCV_EXCP_VIRT_INSTRUCTION_FAULT:
1886             tval = env->bins;
1887             break;
1888         case RISCV_EXCP_BREAKPOINT:
1889             tval = env->badaddr;
1890             if (cs->watchpoint_hit) {
1891                 tval = cs->watchpoint_hit->hitaddr;
1892                 cs->watchpoint_hit = NULL;
1893             }
1894             break;
1895         case RISCV_EXCP_SW_CHECK:
1896             tval = env->sw_check_code;
1897             break;
1898         default:
1899             break;
1900         }
1901         /* ecall is dispatched as one cause so translate based on mode */
1902         if (cause == RISCV_EXCP_U_ECALL) {
1903             assert(env->priv <= 3);
1904 
1905             if (env->priv == PRV_M) {
1906                 cause = RISCV_EXCP_M_ECALL;
1907             } else if (env->priv == PRV_S && env->virt_enabled) {
1908                 cause = RISCV_EXCP_VS_ECALL;
1909             } else if (env->priv == PRV_S && !env->virt_enabled) {
1910                 cause = RISCV_EXCP_S_ECALL;
1911             } else if (env->priv == PRV_U) {
1912                 cause = RISCV_EXCP_U_ECALL;
1913             }
1914         }
1915     }
1916 
1917     trace_riscv_trap(env->mhartid, async, cause, env->pc, tval,
1918                      riscv_cpu_get_trap_name(cause, async));
1919 
1920     qemu_log_mask(CPU_LOG_INT,
1921                   "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", "
1922                   "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n",
1923                   __func__, env->mhartid, async, cause, env->pc, tval,
1924                   riscv_cpu_get_trap_name(cause, async));
1925 
1926     if (env->priv <= PRV_S && cause < 64 &&
1927         (((deleg >> cause) & 1) || s_injected || vs_injected)) {
1928         /* handle the trap in S-mode */
1929         /* save elp status */
1930         if (cpu_get_fcfien(env)) {
1931             env->mstatus = set_field(env->mstatus, MSTATUS_SPELP, env->elp);
1932         }
1933 
1934         if (riscv_has_ext(env, RVH)) {
1935             uint64_t hdeleg = async ? env->hideleg : env->hedeleg;
1936 
1937             if (env->virt_enabled &&
1938                 (((hdeleg >> cause) & 1) || vs_injected)) {
1939                 /* Trap to VS mode */
1940                 /*
1941                  * See if we need to adjust cause. Yes if its VS mode interrupt
1942                  * no if hypervisor has delegated one of hs mode's interrupt
1943                  */
1944                 if (async && (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT ||
1945                               cause == IRQ_VS_EXT)) {
1946                     cause = cause - 1;
1947                 }
1948                 write_gva = false;
1949             } else if (env->virt_enabled) {
1950                 /* Trap into HS mode, from virt */
1951                 riscv_cpu_swap_hypervisor_regs(env);
1952                 env->hstatus = set_field(env->hstatus, HSTATUS_SPVP,
1953                                          env->priv);
1954                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, true);
1955 
1956                 htval = env->guest_phys_fault_addr;
1957 
1958                 virt = false;
1959             } else {
1960                 /* Trap into HS mode */
1961                 env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false);
1962                 htval = env->guest_phys_fault_addr;
1963             }
1964             env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva);
1965         }
1966 
1967         s = env->mstatus;
1968         s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE));
1969         s = set_field(s, MSTATUS_SPP, env->priv);
1970         s = set_field(s, MSTATUS_SIE, 0);
1971         env->mstatus = s;
1972         sxlen = 16 << riscv_cpu_sxl(env);
1973         env->scause = cause | ((target_ulong)async << (sxlen - 1));
1974         env->sepc = env->pc;
1975         env->stval = tval;
1976         env->htval = htval;
1977         env->htinst = tinst;
1978         env->pc = (env->stvec >> 2 << 2) +
1979                   ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
1980         riscv_cpu_set_mode(env, PRV_S, virt);
1981     } else {
1982         /* handle the trap in M-mode */
1983         /* save elp status */
1984         if (cpu_get_fcfien(env)) {
1985             env->mstatus = set_field(env->mstatus, MSTATUS_MPELP, env->elp);
1986         }
1987 
1988         if (riscv_has_ext(env, RVH)) {
1989             if (env->virt_enabled) {
1990                 riscv_cpu_swap_hypervisor_regs(env);
1991             }
1992             env->mstatus = set_field(env->mstatus, MSTATUS_MPV,
1993                                      env->virt_enabled);
1994             if (env->virt_enabled && tval) {
1995                 env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1);
1996             }
1997 
1998             mtval2 = env->guest_phys_fault_addr;
1999 
2000             /* Trapping to M mode, virt is disabled */
2001             virt = false;
2002         }
2003 
2004         s = env->mstatus;
2005         s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE));
2006         s = set_field(s, MSTATUS_MPP, env->priv);
2007         s = set_field(s, MSTATUS_MIE, 0);
2008         env->mstatus = s;
2009         mxlen = 16 << riscv_cpu_mxl(env);
2010         env->mcause = cause | ((target_ulong)async << (mxlen - 1));
2011         env->mepc = env->pc;
2012         env->mtval = tval;
2013         env->mtval2 = mtval2;
2014         env->mtinst = tinst;
2015         env->pc = (env->mtvec >> 2 << 2) +
2016                   ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
2017         riscv_cpu_set_mode(env, PRV_M, virt);
2018     }
2019 
2020     /*
2021      * Interrupt/exception/trap delivery is asynchronous event and as per
2022      * zicfilp spec CPU should clear up the ELP state. No harm in clearing
2023      * unconditionally.
2024      */
2025     env->elp = false;
2026 
2027     /*
2028      * NOTE: it is not necessary to yield load reservations here. It is only
2029      * necessary for an SC from "another hart" to cause a load reservation
2030      * to be yielded. Refer to the memory consistency model section of the
2031      * RISC-V ISA Specification.
2032      */
2033 
2034     env->two_stage_lookup = false;
2035     env->two_stage_indirect_lookup = false;
2036 }
2037 
2038 #endif /* !CONFIG_USER_ONLY */
2039