xref: /openbmc/qemu/target/ppc/excp_helper.c (revision 520e210c)
1 /*
2  *  PowerPC exception emulation helpers for QEMU.
3  *
4  *  Copyright (c) 2003-2007 Jocelyn Mayer
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 #include "qemu/osdep.h"
20 #include "qemu/main-loop.h"
21 #include "cpu.h"
22 #include "exec/helper-proto.h"
23 #include "exec/exec-all.h"
24 #include "exec/cpu_ldst.h"
25 #include "internal.h"
26 #include "helper_regs.h"
27 
28 //#define DEBUG_OP
29 //#define DEBUG_SOFTWARE_TLB
30 //#define DEBUG_EXCEPTIONS
31 
32 #ifdef DEBUG_EXCEPTIONS
33 #  define LOG_EXCP(...) qemu_log(__VA_ARGS__)
34 #else
35 #  define LOG_EXCP(...) do { } while (0)
36 #endif
37 
38 /*****************************************************************************/
39 /* Exception processing */
40 #if defined(CONFIG_USER_ONLY)
41 void ppc_cpu_do_interrupt(CPUState *cs)
42 {
43     PowerPCCPU *cpu = POWERPC_CPU(cs);
44     CPUPPCState *env = &cpu->env;
45 
46     cs->exception_index = POWERPC_EXCP_NONE;
47     env->error_code = 0;
48 }
49 
50 static void ppc_hw_interrupt(CPUPPCState *env)
51 {
52     CPUState *cs = CPU(ppc_env_get_cpu(env));
53 
54     cs->exception_index = POWERPC_EXCP_NONE;
55     env->error_code = 0;
56 }
57 #else /* defined(CONFIG_USER_ONLY) */
58 static inline void dump_syscall(CPUPPCState *env)
59 {
60     qemu_log_mask(CPU_LOG_INT, "syscall r0=%016" PRIx64 " r3=%016" PRIx64
61                   " r4=%016" PRIx64 " r5=%016" PRIx64 " r6=%016" PRIx64
62                   " nip=" TARGET_FMT_lx "\n",
63                   ppc_dump_gpr(env, 0), ppc_dump_gpr(env, 3),
64                   ppc_dump_gpr(env, 4), ppc_dump_gpr(env, 5),
65                   ppc_dump_gpr(env, 6), env->nip);
66 }
67 
68 /* Note that this function should be greatly optimized
69  * when called with a constant excp, from ppc_hw_interrupt
70  */
71 static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp)
72 {
73     CPUState *cs = CPU(cpu);
74     CPUPPCState *env = &cpu->env;
75     target_ulong msr, new_msr, vector;
76     int srr0, srr1, asrr0, asrr1, lev, ail;
77     bool lpes0;
78 
79     qemu_log_mask(CPU_LOG_INT, "Raise exception at " TARGET_FMT_lx
80                   " => %08x (%02x)\n", env->nip, excp, env->error_code);
81 
82     /* new srr1 value excluding must-be-zero bits */
83     if (excp_model == POWERPC_EXCP_BOOKE) {
84         msr = env->msr;
85     } else {
86         msr = env->msr & ~0x783f0000ULL;
87     }
88 
89     /* new interrupt handler msr preserves existing HV and ME unless
90      * explicitly overriden
91      */
92     new_msr = env->msr & (((target_ulong)1 << MSR_ME) | MSR_HVB);
93 
94     /* target registers */
95     srr0 = SPR_SRR0;
96     srr1 = SPR_SRR1;
97     asrr0 = -1;
98     asrr1 = -1;
99 
100     /* check for special resume at 0x100 from doze/nap/sleep/winkle on P7/P8 */
101     if (env->in_pm_state) {
102         env->in_pm_state = false;
103 
104         /* Pretend to be returning from doze always as we don't lose state */
105         msr |= (0x1ull << (63 - 47));
106 
107         /* Non-machine check are routed to 0x100 with a wakeup cause
108          * encoded in SRR1
109          */
110         if (excp != POWERPC_EXCP_MCHECK) {
111             switch (excp) {
112             case POWERPC_EXCP_RESET:
113                 msr |= 0x4ull << (63 - 45);
114                 break;
115             case POWERPC_EXCP_EXTERNAL:
116                 msr |= 0x8ull << (63 - 45);
117                 break;
118             case POWERPC_EXCP_DECR:
119                 msr |= 0x6ull << (63 - 45);
120                 break;
121             case POWERPC_EXCP_SDOOR:
122                 msr |= 0x5ull << (63 - 45);
123                 break;
124             case POWERPC_EXCP_SDOOR_HV:
125                 msr |= 0x3ull << (63 - 45);
126                 break;
127             case POWERPC_EXCP_HV_MAINT:
128                 msr |= 0xaull << (63 - 45);
129                 break;
130             default:
131                 cpu_abort(cs, "Unsupported exception %d in Power Save mode\n",
132                           excp);
133             }
134             excp = POWERPC_EXCP_RESET;
135         }
136     }
137 
138     /* Exception targetting modifiers
139      *
140      * LPES0 is supported on POWER7/8
141      * LPES1 is not supported (old iSeries mode)
142      *
143      * On anything else, we behave as if LPES0 is 1
144      * (externals don't alter MSR:HV)
145      *
146      * AIL is initialized here but can be cleared by
147      * selected exceptions
148      */
149 #if defined(TARGET_PPC64)
150     if (excp_model == POWERPC_EXCP_POWER7 ||
151         excp_model == POWERPC_EXCP_POWER8) {
152         lpes0 = !!(env->spr[SPR_LPCR] & LPCR_LPES0);
153         if (excp_model == POWERPC_EXCP_POWER8) {
154             ail = (env->spr[SPR_LPCR] & LPCR_AIL) >> LPCR_AIL_SHIFT;
155         } else {
156             ail = 0;
157         }
158     } else
159 #endif /* defined(TARGET_PPC64) */
160     {
161         lpes0 = true;
162         ail = 0;
163     }
164 
165     /* Hypervisor emulation assistance interrupt only exists on server
166      * arch 2.05 server or later. We also don't want to generate it if
167      * we don't have HVB in msr_mask (PAPR mode).
168      */
169     if (excp == POWERPC_EXCP_HV_EMU
170 #if defined(TARGET_PPC64)
171         && !((env->mmu_model & POWERPC_MMU_64) && (env->msr_mask & MSR_HVB))
172 #endif /* defined(TARGET_PPC64) */
173 
174     ) {
175         excp = POWERPC_EXCP_PROGRAM;
176     }
177 
178     switch (excp) {
179     case POWERPC_EXCP_NONE:
180         /* Should never happen */
181         return;
182     case POWERPC_EXCP_CRITICAL:    /* Critical input                         */
183         switch (excp_model) {
184         case POWERPC_EXCP_40x:
185             srr0 = SPR_40x_SRR2;
186             srr1 = SPR_40x_SRR3;
187             break;
188         case POWERPC_EXCP_BOOKE:
189             srr0 = SPR_BOOKE_CSRR0;
190             srr1 = SPR_BOOKE_CSRR1;
191             break;
192         case POWERPC_EXCP_G2:
193             break;
194         default:
195             goto excp_invalid;
196         }
197         break;
198     case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
199         if (msr_me == 0) {
200             /* Machine check exception is not enabled.
201              * Enter checkstop state.
202              */
203             fprintf(stderr, "Machine check while not allowed. "
204                     "Entering checkstop state\n");
205             if (qemu_log_separate()) {
206                 qemu_log("Machine check while not allowed. "
207                         "Entering checkstop state\n");
208             }
209             cs->halted = 1;
210             cpu_interrupt_exittb(cs);
211         }
212         if (env->msr_mask & MSR_HVB) {
213             /* ISA specifies HV, but can be delivered to guest with HV clear
214              * (e.g., see FWNMI in PAPR).
215              */
216             new_msr |= (target_ulong)MSR_HVB;
217         }
218         ail = 0;
219 
220         /* machine check exceptions don't have ME set */
221         new_msr &= ~((target_ulong)1 << MSR_ME);
222 
223         /* XXX: should also have something loaded in DAR / DSISR */
224         switch (excp_model) {
225         case POWERPC_EXCP_40x:
226             srr0 = SPR_40x_SRR2;
227             srr1 = SPR_40x_SRR3;
228             break;
229         case POWERPC_EXCP_BOOKE:
230             /* FIXME: choose one or the other based on CPU type */
231             srr0 = SPR_BOOKE_MCSRR0;
232             srr1 = SPR_BOOKE_MCSRR1;
233             asrr0 = SPR_BOOKE_CSRR0;
234             asrr1 = SPR_BOOKE_CSRR1;
235             break;
236         default:
237             break;
238         }
239         break;
240     case POWERPC_EXCP_DSI:       /* Data storage exception                   */
241         LOG_EXCP("DSI exception: DSISR=" TARGET_FMT_lx" DAR=" TARGET_FMT_lx
242                  "\n", env->spr[SPR_DSISR], env->spr[SPR_DAR]);
243         break;
244     case POWERPC_EXCP_ISI:       /* Instruction storage exception            */
245         LOG_EXCP("ISI exception: msr=" TARGET_FMT_lx ", nip=" TARGET_FMT_lx
246                  "\n", msr, env->nip);
247         msr |= env->error_code;
248         break;
249     case POWERPC_EXCP_EXTERNAL:  /* External input                           */
250         cs = CPU(cpu);
251 
252         if (!lpes0) {
253             new_msr |= (target_ulong)MSR_HVB;
254             new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
255             srr0 = SPR_HSRR0;
256             srr1 = SPR_HSRR1;
257         }
258         if (env->mpic_proxy) {
259             /* IACK the IRQ on delivery */
260             env->spr[SPR_BOOKE_EPR] = ldl_phys(cs->as, env->mpic_iack);
261         }
262         break;
263     case POWERPC_EXCP_ALIGN:     /* Alignment exception                      */
264         /* Get rS/rD and rA from faulting opcode */
265         /* Note: the opcode fields will not be set properly for a direct
266          * store load/store, but nobody cares as nobody actually uses
267          * direct store segments.
268          */
269         env->spr[SPR_DSISR] |= (env->error_code & 0x03FF0000) >> 16;
270         break;
271     case POWERPC_EXCP_PROGRAM:   /* Program exception                        */
272         switch (env->error_code & ~0xF) {
273         case POWERPC_EXCP_FP:
274             if ((msr_fe0 == 0 && msr_fe1 == 0) || msr_fp == 0) {
275                 LOG_EXCP("Ignore floating point exception\n");
276                 cs->exception_index = POWERPC_EXCP_NONE;
277                 env->error_code = 0;
278                 return;
279             }
280 
281             /* FP exceptions always have NIP pointing to the faulting
282              * instruction, so always use store_next and claim we are
283              * precise in the MSR.
284              */
285             msr |= 0x00100000;
286             env->spr[SPR_BOOKE_ESR] = ESR_FP;
287             break;
288         case POWERPC_EXCP_INVAL:
289             LOG_EXCP("Invalid instruction at " TARGET_FMT_lx "\n", env->nip);
290             msr |= 0x00080000;
291             env->spr[SPR_BOOKE_ESR] = ESR_PIL;
292             break;
293         case POWERPC_EXCP_PRIV:
294             msr |= 0x00040000;
295             env->spr[SPR_BOOKE_ESR] = ESR_PPR;
296             break;
297         case POWERPC_EXCP_TRAP:
298             msr |= 0x00020000;
299             env->spr[SPR_BOOKE_ESR] = ESR_PTR;
300             break;
301         default:
302             /* Should never occur */
303             cpu_abort(cs, "Invalid program exception %d. Aborting\n",
304                       env->error_code);
305             break;
306         }
307         break;
308     case POWERPC_EXCP_SYSCALL:   /* System call exception                    */
309         dump_syscall(env);
310         lev = env->error_code;
311 
312         /* We need to correct the NIP which in this case is supposed
313          * to point to the next instruction
314          */
315         env->nip += 4;
316 
317         /* "PAPR mode" built-in hypercall emulation */
318         if ((lev == 1) && cpu->vhyp) {
319             PPCVirtualHypervisorClass *vhc =
320                 PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp);
321             vhc->hypercall(cpu->vhyp, cpu);
322             return;
323         }
324         if (lev == 1) {
325             new_msr |= (target_ulong)MSR_HVB;
326         }
327         break;
328     case POWERPC_EXCP_FPU:       /* Floating-point unavailable exception     */
329     case POWERPC_EXCP_APU:       /* Auxiliary processor unavailable          */
330     case POWERPC_EXCP_DECR:      /* Decrementer exception                    */
331         break;
332     case POWERPC_EXCP_FIT:       /* Fixed-interval timer interrupt           */
333         /* FIT on 4xx */
334         LOG_EXCP("FIT exception\n");
335         break;
336     case POWERPC_EXCP_WDT:       /* Watchdog timer interrupt                 */
337         LOG_EXCP("WDT exception\n");
338         switch (excp_model) {
339         case POWERPC_EXCP_BOOKE:
340             srr0 = SPR_BOOKE_CSRR0;
341             srr1 = SPR_BOOKE_CSRR1;
342             break;
343         default:
344             break;
345         }
346         break;
347     case POWERPC_EXCP_DTLB:      /* Data TLB error                           */
348     case POWERPC_EXCP_ITLB:      /* Instruction TLB error                    */
349         break;
350     case POWERPC_EXCP_DEBUG:     /* Debug interrupt                          */
351         if (env->flags & POWERPC_FLAG_DE) {
352             /* FIXME: choose one or the other based on CPU type */
353             srr0 = SPR_BOOKE_DSRR0;
354             srr1 = SPR_BOOKE_DSRR1;
355             asrr0 = SPR_BOOKE_CSRR0;
356             asrr1 = SPR_BOOKE_CSRR1;
357             /* DBSR already modified by caller */
358         } else {
359             cpu_abort(cs, "Debug exception triggered on unsupported model\n");
360         }
361         break;
362     case POWERPC_EXCP_SPEU:      /* SPE/embedded floating-point unavailable  */
363         env->spr[SPR_BOOKE_ESR] = ESR_SPV;
364         break;
365     case POWERPC_EXCP_EFPDI:     /* Embedded floating-point data interrupt   */
366         /* XXX: TODO */
367         cpu_abort(cs, "Embedded floating point data exception "
368                   "is not implemented yet !\n");
369         env->spr[SPR_BOOKE_ESR] = ESR_SPV;
370         break;
371     case POWERPC_EXCP_EFPRI:     /* Embedded floating-point round interrupt  */
372         /* XXX: TODO */
373         cpu_abort(cs, "Embedded floating point round exception "
374                   "is not implemented yet !\n");
375         env->spr[SPR_BOOKE_ESR] = ESR_SPV;
376         break;
377     case POWERPC_EXCP_EPERFM:    /* Embedded performance monitor interrupt   */
378         /* XXX: TODO */
379         cpu_abort(cs,
380                   "Performance counter exception is not implemented yet !\n");
381         break;
382     case POWERPC_EXCP_DOORI:     /* Embedded doorbell interrupt              */
383         break;
384     case POWERPC_EXCP_DOORCI:    /* Embedded doorbell critical interrupt     */
385         srr0 = SPR_BOOKE_CSRR0;
386         srr1 = SPR_BOOKE_CSRR1;
387         break;
388     case POWERPC_EXCP_RESET:     /* System reset exception                   */
389         /* A power-saving exception sets ME, otherwise it is unchanged */
390         if (msr_pow) {
391             /* indicate that we resumed from power save mode */
392             msr |= 0x10000;
393             new_msr |= ((target_ulong)1 << MSR_ME);
394         }
395         if (env->msr_mask & MSR_HVB) {
396             /* ISA specifies HV, but can be delivered to guest with HV clear
397              * (e.g., see FWNMI in PAPR, NMI injection in QEMU).
398              */
399             new_msr |= (target_ulong)MSR_HVB;
400         } else {
401             if (msr_pow) {
402                 cpu_abort(cs, "Trying to deliver power-saving system reset "
403                           "exception %d with no HV support\n", excp);
404             }
405         }
406         ail = 0;
407         break;
408     case POWERPC_EXCP_DSEG:      /* Data segment exception                   */
409     case POWERPC_EXCP_ISEG:      /* Instruction segment exception            */
410     case POWERPC_EXCP_TRACE:     /* Trace exception                          */
411         break;
412     case POWERPC_EXCP_HDECR:     /* Hypervisor decrementer exception         */
413     case POWERPC_EXCP_HDSI:      /* Hypervisor data storage exception        */
414     case POWERPC_EXCP_HISI:      /* Hypervisor instruction storage exception */
415     case POWERPC_EXCP_HDSEG:     /* Hypervisor data segment exception        */
416     case POWERPC_EXCP_HISEG:     /* Hypervisor instruction segment exception */
417     case POWERPC_EXCP_SDOOR_HV:  /* Hypervisor Doorbell interrupt            */
418     case POWERPC_EXCP_HV_EMU:
419         srr0 = SPR_HSRR0;
420         srr1 = SPR_HSRR1;
421         new_msr |= (target_ulong)MSR_HVB;
422         new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
423         break;
424     case POWERPC_EXCP_VPU:       /* Vector unavailable exception             */
425     case POWERPC_EXCP_VSXU:       /* VSX unavailable exception               */
426     case POWERPC_EXCP_FU:         /* Facility unavailable exception          */
427 #ifdef TARGET_PPC64
428         env->spr[SPR_FSCR] |= ((target_ulong)env->error_code << 56);
429 #endif
430         break;
431     case POWERPC_EXCP_PIT:       /* Programmable interval timer interrupt    */
432         LOG_EXCP("PIT exception\n");
433         break;
434     case POWERPC_EXCP_IO:        /* IO error exception                       */
435         /* XXX: TODO */
436         cpu_abort(cs, "601 IO error exception is not implemented yet !\n");
437         break;
438     case POWERPC_EXCP_RUNM:      /* Run mode exception                       */
439         /* XXX: TODO */
440         cpu_abort(cs, "601 run mode exception is not implemented yet !\n");
441         break;
442     case POWERPC_EXCP_EMUL:      /* Emulation trap exception                 */
443         /* XXX: TODO */
444         cpu_abort(cs, "602 emulation trap exception "
445                   "is not implemented yet !\n");
446         break;
447     case POWERPC_EXCP_IFTLB:     /* Instruction fetch TLB error              */
448         switch (excp_model) {
449         case POWERPC_EXCP_602:
450         case POWERPC_EXCP_603:
451         case POWERPC_EXCP_603E:
452         case POWERPC_EXCP_G2:
453             goto tlb_miss_tgpr;
454         case POWERPC_EXCP_7x5:
455             goto tlb_miss;
456         case POWERPC_EXCP_74xx:
457             goto tlb_miss_74xx;
458         default:
459             cpu_abort(cs, "Invalid instruction TLB miss exception\n");
460             break;
461         }
462         break;
463     case POWERPC_EXCP_DLTLB:     /* Data load TLB miss                       */
464         switch (excp_model) {
465         case POWERPC_EXCP_602:
466         case POWERPC_EXCP_603:
467         case POWERPC_EXCP_603E:
468         case POWERPC_EXCP_G2:
469             goto tlb_miss_tgpr;
470         case POWERPC_EXCP_7x5:
471             goto tlb_miss;
472         case POWERPC_EXCP_74xx:
473             goto tlb_miss_74xx;
474         default:
475             cpu_abort(cs, "Invalid data load TLB miss exception\n");
476             break;
477         }
478         break;
479     case POWERPC_EXCP_DSTLB:     /* Data store TLB miss                      */
480         switch (excp_model) {
481         case POWERPC_EXCP_602:
482         case POWERPC_EXCP_603:
483         case POWERPC_EXCP_603E:
484         case POWERPC_EXCP_G2:
485         tlb_miss_tgpr:
486             /* Swap temporary saved registers with GPRs */
487             if (!(new_msr & ((target_ulong)1 << MSR_TGPR))) {
488                 new_msr |= (target_ulong)1 << MSR_TGPR;
489                 hreg_swap_gpr_tgpr(env);
490             }
491             goto tlb_miss;
492         case POWERPC_EXCP_7x5:
493         tlb_miss:
494 #if defined(DEBUG_SOFTWARE_TLB)
495             if (qemu_log_enabled()) {
496                 const char *es;
497                 target_ulong *miss, *cmp;
498                 int en;
499 
500                 if (excp == POWERPC_EXCP_IFTLB) {
501                     es = "I";
502                     en = 'I';
503                     miss = &env->spr[SPR_IMISS];
504                     cmp = &env->spr[SPR_ICMP];
505                 } else {
506                     if (excp == POWERPC_EXCP_DLTLB) {
507                         es = "DL";
508                     } else {
509                         es = "DS";
510                     }
511                     en = 'D';
512                     miss = &env->spr[SPR_DMISS];
513                     cmp = &env->spr[SPR_DCMP];
514                 }
515                 qemu_log("6xx %sTLB miss: %cM " TARGET_FMT_lx " %cC "
516                          TARGET_FMT_lx " H1 " TARGET_FMT_lx " H2 "
517                          TARGET_FMT_lx " %08x\n", es, en, *miss, en, *cmp,
518                          env->spr[SPR_HASH1], env->spr[SPR_HASH2],
519                          env->error_code);
520             }
521 #endif
522             msr |= env->crf[0] << 28;
523             msr |= env->error_code; /* key, D/I, S/L bits */
524             /* Set way using a LRU mechanism */
525             msr |= ((env->last_way + 1) & (env->nb_ways - 1)) << 17;
526             break;
527         case POWERPC_EXCP_74xx:
528         tlb_miss_74xx:
529 #if defined(DEBUG_SOFTWARE_TLB)
530             if (qemu_log_enabled()) {
531                 const char *es;
532                 target_ulong *miss, *cmp;
533                 int en;
534 
535                 if (excp == POWERPC_EXCP_IFTLB) {
536                     es = "I";
537                     en = 'I';
538                     miss = &env->spr[SPR_TLBMISS];
539                     cmp = &env->spr[SPR_PTEHI];
540                 } else {
541                     if (excp == POWERPC_EXCP_DLTLB) {
542                         es = "DL";
543                     } else {
544                         es = "DS";
545                     }
546                     en = 'D';
547                     miss = &env->spr[SPR_TLBMISS];
548                     cmp = &env->spr[SPR_PTEHI];
549                 }
550                 qemu_log("74xx %sTLB miss: %cM " TARGET_FMT_lx " %cC "
551                          TARGET_FMT_lx " %08x\n", es, en, *miss, en, *cmp,
552                          env->error_code);
553             }
554 #endif
555             msr |= env->error_code; /* key bit */
556             break;
557         default:
558             cpu_abort(cs, "Invalid data store TLB miss exception\n");
559             break;
560         }
561         break;
562     case POWERPC_EXCP_FPA:       /* Floating-point assist exception          */
563         /* XXX: TODO */
564         cpu_abort(cs, "Floating point assist exception "
565                   "is not implemented yet !\n");
566         break;
567     case POWERPC_EXCP_DABR:      /* Data address breakpoint                  */
568         /* XXX: TODO */
569         cpu_abort(cs, "DABR exception is not implemented yet !\n");
570         break;
571     case POWERPC_EXCP_IABR:      /* Instruction address breakpoint           */
572         /* XXX: TODO */
573         cpu_abort(cs, "IABR exception is not implemented yet !\n");
574         break;
575     case POWERPC_EXCP_SMI:       /* System management interrupt              */
576         /* XXX: TODO */
577         cpu_abort(cs, "SMI exception is not implemented yet !\n");
578         break;
579     case POWERPC_EXCP_THERM:     /* Thermal interrupt                        */
580         /* XXX: TODO */
581         cpu_abort(cs, "Thermal management exception "
582                   "is not implemented yet !\n");
583         break;
584     case POWERPC_EXCP_PERFM:     /* Embedded performance monitor interrupt   */
585         /* XXX: TODO */
586         cpu_abort(cs,
587                   "Performance counter exception is not implemented yet !\n");
588         break;
589     case POWERPC_EXCP_VPUA:      /* Vector assist exception                  */
590         /* XXX: TODO */
591         cpu_abort(cs, "VPU assist exception is not implemented yet !\n");
592         break;
593     case POWERPC_EXCP_SOFTP:     /* Soft patch exception                     */
594         /* XXX: TODO */
595         cpu_abort(cs,
596                   "970 soft-patch exception is not implemented yet !\n");
597         break;
598     case POWERPC_EXCP_MAINT:     /* Maintenance exception                    */
599         /* XXX: TODO */
600         cpu_abort(cs,
601                   "970 maintenance exception is not implemented yet !\n");
602         break;
603     case POWERPC_EXCP_MEXTBR:    /* Maskable external breakpoint             */
604         /* XXX: TODO */
605         cpu_abort(cs, "Maskable external exception "
606                   "is not implemented yet !\n");
607         break;
608     case POWERPC_EXCP_NMEXTBR:   /* Non maskable external breakpoint         */
609         /* XXX: TODO */
610         cpu_abort(cs, "Non maskable external exception "
611                   "is not implemented yet !\n");
612         break;
613     default:
614     excp_invalid:
615         cpu_abort(cs, "Invalid PowerPC exception %d. Aborting\n", excp);
616         break;
617     }
618 
619     /* Save PC */
620     env->spr[srr0] = env->nip;
621 
622     /* Save MSR */
623     env->spr[srr1] = msr;
624 
625     /* Sanity check */
626     if (!(env->msr_mask & MSR_HVB)) {
627         if (new_msr & MSR_HVB) {
628             cpu_abort(cs, "Trying to deliver HV exception (MSR) %d with "
629                       "no HV support\n", excp);
630         }
631         if (srr0 == SPR_HSRR0) {
632             cpu_abort(cs, "Trying to deliver HV exception (HSRR) %d with "
633                       "no HV support\n", excp);
634         }
635     }
636 
637     /* If any alternate SRR register are defined, duplicate saved values */
638     if (asrr0 != -1) {
639         env->spr[asrr0] = env->spr[srr0];
640     }
641     if (asrr1 != -1) {
642         env->spr[asrr1] = env->spr[srr1];
643     }
644 
645     /* Sort out endianness of interrupt, this differs depending on the
646      * CPU, the HV mode, etc...
647      */
648 #ifdef TARGET_PPC64
649     if (excp_model == POWERPC_EXCP_POWER7) {
650         if (!(new_msr & MSR_HVB) && (env->spr[SPR_LPCR] & LPCR_ILE)) {
651             new_msr |= (target_ulong)1 << MSR_LE;
652         }
653     } else if (excp_model == POWERPC_EXCP_POWER8) {
654         if (new_msr & MSR_HVB) {
655             if (env->spr[SPR_HID0] & (HID0_HILE | HID0_POWER9_HILE)) {
656                 new_msr |= (target_ulong)1 << MSR_LE;
657             }
658         } else if (env->spr[SPR_LPCR] & LPCR_ILE) {
659             new_msr |= (target_ulong)1 << MSR_LE;
660         }
661     } else if (msr_ile) {
662         new_msr |= (target_ulong)1 << MSR_LE;
663     }
664 #else
665     if (msr_ile) {
666         new_msr |= (target_ulong)1 << MSR_LE;
667     }
668 #endif
669 
670     /* Jump to handler */
671     vector = env->excp_vectors[excp];
672     if (vector == (target_ulong)-1ULL) {
673         cpu_abort(cs, "Raised an exception without defined vector %d\n",
674                   excp);
675     }
676     vector |= env->excp_prefix;
677 
678     /* AIL only works if there is no HV transition and we are running with
679      * translations enabled
680      */
681     if (!((msr >> MSR_IR) & 1) || !((msr >> MSR_DR) & 1) ||
682         ((new_msr & MSR_HVB) && !(msr & MSR_HVB))) {
683         ail = 0;
684     }
685     /* Handle AIL */
686     if (ail) {
687         new_msr |= (1 << MSR_IR) | (1 << MSR_DR);
688         switch(ail) {
689         case AIL_0001_8000:
690             vector |= 0x18000;
691             break;
692         case AIL_C000_0000_0000_4000:
693             vector |= 0xc000000000004000ull;
694             break;
695         default:
696             cpu_abort(cs, "Invalid AIL combination %d\n", ail);
697             break;
698         }
699     }
700 
701 #if defined(TARGET_PPC64)
702     if (excp_model == POWERPC_EXCP_BOOKE) {
703         if (env->spr[SPR_BOOKE_EPCR] & EPCR_ICM) {
704             /* Cat.64-bit: EPCR.ICM is copied to MSR.CM */
705             new_msr |= (target_ulong)1 << MSR_CM;
706         } else {
707             vector = (uint32_t)vector;
708         }
709     } else {
710         if (!msr_isf && !(env->mmu_model & POWERPC_MMU_64)) {
711             vector = (uint32_t)vector;
712         } else {
713             new_msr |= (target_ulong)1 << MSR_SF;
714         }
715     }
716 #endif
717     /* We don't use hreg_store_msr here as already have treated
718      * any special case that could occur. Just store MSR and update hflags
719      *
720      * Note: We *MUST* not use hreg_store_msr() as-is anyway because it
721      * will prevent setting of the HV bit which some exceptions might need
722      * to do.
723      */
724     env->msr = new_msr & env->msr_mask;
725     hreg_compute_hflags(env);
726     env->nip = vector;
727     /* Reset exception state */
728     cs->exception_index = POWERPC_EXCP_NONE;
729     env->error_code = 0;
730 
731     /* Reset the reservation */
732     env->reserve_addr = -1;
733 
734     /* Any interrupt is context synchronizing, check if TCG TLB
735      * needs a delayed flush on ppc64
736      */
737     check_tlb_flush(env, false);
738 }
739 
740 void ppc_cpu_do_interrupt(CPUState *cs)
741 {
742     PowerPCCPU *cpu = POWERPC_CPU(cs);
743     CPUPPCState *env = &cpu->env;
744 
745     powerpc_excp(cpu, env->excp_model, cs->exception_index);
746 }
747 
748 static void ppc_hw_interrupt(CPUPPCState *env)
749 {
750     PowerPCCPU *cpu = ppc_env_get_cpu(env);
751 
752     /* External reset */
753     if (env->pending_interrupts & (1 << PPC_INTERRUPT_RESET)) {
754         env->pending_interrupts &= ~(1 << PPC_INTERRUPT_RESET);
755         powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_RESET);
756         return;
757     }
758     /* Machine check exception */
759     if (env->pending_interrupts & (1 << PPC_INTERRUPT_MCK)) {
760         env->pending_interrupts &= ~(1 << PPC_INTERRUPT_MCK);
761         powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_MCHECK);
762         return;
763     }
764 #if 0 /* TODO */
765     /* External debug exception */
766     if (env->pending_interrupts & (1 << PPC_INTERRUPT_DEBUG)) {
767         env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DEBUG);
768         powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DEBUG);
769         return;
770     }
771 #endif
772     /* Hypervisor decrementer exception */
773     if (env->pending_interrupts & (1 << PPC_INTERRUPT_HDECR)) {
774         /* LPCR will be clear when not supported so this will work */
775         bool hdice = !!(env->spr[SPR_LPCR] & LPCR_HDICE);
776         if ((msr_ee != 0 || msr_hv == 0) && hdice) {
777             /* HDEC clears on delivery */
778             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_HDECR);
779             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_HDECR);
780             return;
781         }
782     }
783     /* Extermal interrupt can ignore MSR:EE under some circumstances */
784     if (env->pending_interrupts & (1 << PPC_INTERRUPT_EXT)) {
785         bool lpes0 = !!(env->spr[SPR_LPCR] & LPCR_LPES0);
786         if (msr_ee != 0 || (env->has_hv_mode && msr_hv == 0 && !lpes0)) {
787             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_EXTERNAL);
788             return;
789         }
790     }
791     if (msr_ce != 0) {
792         /* External critical interrupt */
793         if (env->pending_interrupts & (1 << PPC_INTERRUPT_CEXT)) {
794             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_CRITICAL);
795             return;
796         }
797     }
798     if (msr_ee != 0) {
799         /* Watchdog timer on embedded PowerPC */
800         if (env->pending_interrupts & (1 << PPC_INTERRUPT_WDT)) {
801             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_WDT);
802             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_WDT);
803             return;
804         }
805         if (env->pending_interrupts & (1 << PPC_INTERRUPT_CDOORBELL)) {
806             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_CDOORBELL);
807             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DOORCI);
808             return;
809         }
810         /* Fixed interval timer on embedded PowerPC */
811         if (env->pending_interrupts & (1 << PPC_INTERRUPT_FIT)) {
812             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_FIT);
813             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_FIT);
814             return;
815         }
816         /* Programmable interval timer on embedded PowerPC */
817         if (env->pending_interrupts & (1 << PPC_INTERRUPT_PIT)) {
818             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_PIT);
819             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_PIT);
820             return;
821         }
822         /* Decrementer exception */
823         if (env->pending_interrupts & (1 << PPC_INTERRUPT_DECR)) {
824             if (ppc_decr_clear_on_delivery(env)) {
825                 env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DECR);
826             }
827             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DECR);
828             return;
829         }
830         if (env->pending_interrupts & (1 << PPC_INTERRUPT_DOORBELL)) {
831             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DOORBELL);
832             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DOORI);
833             return;
834         }
835         if (env->pending_interrupts & (1 << PPC_INTERRUPT_HDOORBELL)) {
836             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_HDOORBELL);
837             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_SDOOR_HV);
838             return;
839         }
840         if (env->pending_interrupts & (1 << PPC_INTERRUPT_PERFM)) {
841             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_PERFM);
842             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_PERFM);
843             return;
844         }
845         /* Thermal interrupt */
846         if (env->pending_interrupts & (1 << PPC_INTERRUPT_THERM)) {
847             env->pending_interrupts &= ~(1 << PPC_INTERRUPT_THERM);
848             powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_THERM);
849             return;
850         }
851     }
852 }
853 
854 void ppc_cpu_do_system_reset(CPUState *cs)
855 {
856     PowerPCCPU *cpu = POWERPC_CPU(cs);
857     CPUPPCState *env = &cpu->env;
858 
859     powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_RESET);
860 }
861 #endif /* !CONFIG_USER_ONLY */
862 
863 bool ppc_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
864 {
865     PowerPCCPU *cpu = POWERPC_CPU(cs);
866     CPUPPCState *env = &cpu->env;
867 
868     if (interrupt_request & CPU_INTERRUPT_HARD) {
869         ppc_hw_interrupt(env);
870         if (env->pending_interrupts == 0) {
871             cs->interrupt_request &= ~CPU_INTERRUPT_HARD;
872         }
873         return true;
874     }
875     return false;
876 }
877 
878 #if defined(DEBUG_OP)
879 static void cpu_dump_rfi(target_ulong RA, target_ulong msr)
880 {
881     qemu_log("Return from exception at " TARGET_FMT_lx " with flags "
882              TARGET_FMT_lx "\n", RA, msr);
883 }
884 #endif
885 
886 /*****************************************************************************/
887 /* Exceptions processing helpers */
888 
889 void raise_exception_err_ra(CPUPPCState *env, uint32_t exception,
890                             uint32_t error_code, uintptr_t raddr)
891 {
892     CPUState *cs = CPU(ppc_env_get_cpu(env));
893 
894     cs->exception_index = exception;
895     env->error_code = error_code;
896     cpu_loop_exit_restore(cs, raddr);
897 }
898 
899 void raise_exception_err(CPUPPCState *env, uint32_t exception,
900                          uint32_t error_code)
901 {
902     raise_exception_err_ra(env, exception, error_code, 0);
903 }
904 
905 void raise_exception(CPUPPCState *env, uint32_t exception)
906 {
907     raise_exception_err_ra(env, exception, 0, 0);
908 }
909 
910 void raise_exception_ra(CPUPPCState *env, uint32_t exception,
911                         uintptr_t raddr)
912 {
913     raise_exception_err_ra(env, exception, 0, raddr);
914 }
915 
916 void helper_raise_exception_err(CPUPPCState *env, uint32_t exception,
917                                 uint32_t error_code)
918 {
919     raise_exception_err_ra(env, exception, error_code, 0);
920 }
921 
922 void helper_raise_exception(CPUPPCState *env, uint32_t exception)
923 {
924     raise_exception_err_ra(env, exception, 0, 0);
925 }
926 
927 #if !defined(CONFIG_USER_ONLY)
928 void helper_store_msr(CPUPPCState *env, target_ulong val)
929 {
930     uint32_t excp = hreg_store_msr(env, val, 0);
931 
932     if (excp != 0) {
933         CPUState *cs = CPU(ppc_env_get_cpu(env));
934         cpu_interrupt_exittb(cs);
935         raise_exception(env, excp);
936     }
937 }
938 
939 #if defined(TARGET_PPC64)
940 void helper_pminsn(CPUPPCState *env, powerpc_pm_insn_t insn)
941 {
942     CPUState *cs;
943 
944     cs = CPU(ppc_env_get_cpu(env));
945     cs->halted = 1;
946     env->in_pm_state = true;
947 
948     /* The architecture specifies that HDEC interrupts are
949      * discarded in PM states
950      */
951     env->pending_interrupts &= ~(1 << PPC_INTERRUPT_HDECR);
952 
953     /* Technically, nap doesn't set EE, but if we don't set it
954      * then ppc_hw_interrupt() won't deliver. We could add some
955      * other tests there based on LPCR but it's simpler to just
956      * whack EE in. It will be cleared by the 0x100 at wakeup
957      * anyway. It will still be observable by the guest in SRR1
958      * but this doesn't seem to be a problem.
959      */
960     env->msr |= (1ull << MSR_EE);
961     raise_exception(env, EXCP_HLT);
962 }
963 #endif /* defined(TARGET_PPC64) */
964 
965 static inline void do_rfi(CPUPPCState *env, target_ulong nip, target_ulong msr)
966 {
967     CPUState *cs = CPU(ppc_env_get_cpu(env));
968 
969     /* MSR:POW cannot be set by any form of rfi */
970     msr &= ~(1ULL << MSR_POW);
971 
972 #if defined(TARGET_PPC64)
973     /* Switching to 32-bit ? Crop the nip */
974     if (!msr_is_64bit(env, msr)) {
975         nip = (uint32_t)nip;
976     }
977 #else
978     nip = (uint32_t)nip;
979 #endif
980     /* XXX: beware: this is false if VLE is supported */
981     env->nip = nip & ~((target_ulong)0x00000003);
982     hreg_store_msr(env, msr, 1);
983 #if defined(DEBUG_OP)
984     cpu_dump_rfi(env->nip, env->msr);
985 #endif
986     /* No need to raise an exception here,
987      * as rfi is always the last insn of a TB
988      */
989     cpu_interrupt_exittb(cs);
990     /* Reset the reservation */
991     env->reserve_addr = -1;
992 
993     /* Context synchronizing: check if TCG TLB needs flush */
994     check_tlb_flush(env, false);
995 }
996 
997 void helper_rfi(CPUPPCState *env)
998 {
999     do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1] & 0xfffffffful);
1000 }
1001 
1002 #define MSR_BOOK3S_MASK
1003 #if defined(TARGET_PPC64)
1004 void helper_rfid(CPUPPCState *env)
1005 {
1006     /* The architeture defines a number of rules for which bits
1007      * can change but in practice, we handle this in hreg_store_msr()
1008      * which will be called by do_rfi(), so there is no need to filter
1009      * here
1010      */
1011     do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1]);
1012 }
1013 
1014 void helper_hrfid(CPUPPCState *env)
1015 {
1016     do_rfi(env, env->spr[SPR_HSRR0], env->spr[SPR_HSRR1]);
1017 }
1018 #endif
1019 
1020 /*****************************************************************************/
1021 /* Embedded PowerPC specific helpers */
1022 void helper_40x_rfci(CPUPPCState *env)
1023 {
1024     do_rfi(env, env->spr[SPR_40x_SRR2], env->spr[SPR_40x_SRR3]);
1025 }
1026 
1027 void helper_rfci(CPUPPCState *env)
1028 {
1029     do_rfi(env, env->spr[SPR_BOOKE_CSRR0], env->spr[SPR_BOOKE_CSRR1]);
1030 }
1031 
1032 void helper_rfdi(CPUPPCState *env)
1033 {
1034     /* FIXME: choose CSRR1 or DSRR1 based on cpu type */
1035     do_rfi(env, env->spr[SPR_BOOKE_DSRR0], env->spr[SPR_BOOKE_DSRR1]);
1036 }
1037 
1038 void helper_rfmci(CPUPPCState *env)
1039 {
1040     /* FIXME: choose CSRR1 or MCSRR1 based on cpu type */
1041     do_rfi(env, env->spr[SPR_BOOKE_MCSRR0], env->spr[SPR_BOOKE_MCSRR1]);
1042 }
1043 #endif
1044 
1045 void helper_tw(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
1046                uint32_t flags)
1047 {
1048     if (!likely(!(((int32_t)arg1 < (int32_t)arg2 && (flags & 0x10)) ||
1049                   ((int32_t)arg1 > (int32_t)arg2 && (flags & 0x08)) ||
1050                   ((int32_t)arg1 == (int32_t)arg2 && (flags & 0x04)) ||
1051                   ((uint32_t)arg1 < (uint32_t)arg2 && (flags & 0x02)) ||
1052                   ((uint32_t)arg1 > (uint32_t)arg2 && (flags & 0x01))))) {
1053         raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
1054                                POWERPC_EXCP_TRAP, GETPC());
1055     }
1056 }
1057 
1058 #if defined(TARGET_PPC64)
1059 void helper_td(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
1060                uint32_t flags)
1061 {
1062     if (!likely(!(((int64_t)arg1 < (int64_t)arg2 && (flags & 0x10)) ||
1063                   ((int64_t)arg1 > (int64_t)arg2 && (flags & 0x08)) ||
1064                   ((int64_t)arg1 == (int64_t)arg2 && (flags & 0x04)) ||
1065                   ((uint64_t)arg1 < (uint64_t)arg2 && (flags & 0x02)) ||
1066                   ((uint64_t)arg1 > (uint64_t)arg2 && (flags & 0x01))))) {
1067         raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
1068                                POWERPC_EXCP_TRAP, GETPC());
1069     }
1070 }
1071 #endif
1072 
1073 #if !defined(CONFIG_USER_ONLY)
1074 /*****************************************************************************/
1075 /* PowerPC 601 specific instructions (POWER bridge) */
1076 
1077 void helper_rfsvc(CPUPPCState *env)
1078 {
1079     do_rfi(env, env->lr, env->ctr & 0x0000FFFF);
1080 }
1081 
1082 /* Embedded.Processor Control */
1083 static int dbell2irq(target_ulong rb)
1084 {
1085     int msg = rb & DBELL_TYPE_MASK;
1086     int irq = -1;
1087 
1088     switch (msg) {
1089     case DBELL_TYPE_DBELL:
1090         irq = PPC_INTERRUPT_DOORBELL;
1091         break;
1092     case DBELL_TYPE_DBELL_CRIT:
1093         irq = PPC_INTERRUPT_CDOORBELL;
1094         break;
1095     case DBELL_TYPE_G_DBELL:
1096     case DBELL_TYPE_G_DBELL_CRIT:
1097     case DBELL_TYPE_G_DBELL_MC:
1098         /* XXX implement */
1099     default:
1100         break;
1101     }
1102 
1103     return irq;
1104 }
1105 
1106 void helper_msgclr(CPUPPCState *env, target_ulong rb)
1107 {
1108     int irq = dbell2irq(rb);
1109 
1110     if (irq < 0) {
1111         return;
1112     }
1113 
1114     env->pending_interrupts &= ~(1 << irq);
1115 }
1116 
1117 void helper_msgsnd(target_ulong rb)
1118 {
1119     int irq = dbell2irq(rb);
1120     int pir = rb & DBELL_PIRTAG_MASK;
1121     CPUState *cs;
1122 
1123     if (irq < 0) {
1124         return;
1125     }
1126 
1127     qemu_mutex_lock_iothread();
1128     CPU_FOREACH(cs) {
1129         PowerPCCPU *cpu = POWERPC_CPU(cs);
1130         CPUPPCState *cenv = &cpu->env;
1131 
1132         if ((rb & DBELL_BRDCAST) || (cenv->spr[SPR_BOOKE_PIR] == pir)) {
1133             cenv->pending_interrupts |= 1 << irq;
1134             cpu_interrupt(cs, CPU_INTERRUPT_HARD);
1135         }
1136     }
1137     qemu_mutex_unlock_iothread();
1138 }
1139 
1140 /* Server Processor Control */
1141 static int book3s_dbell2irq(target_ulong rb)
1142 {
1143     int msg = rb & DBELL_TYPE_MASK;
1144 
1145     /* A Directed Hypervisor Doorbell message is sent only if the
1146      * message type is 5. All other types are reserved and the
1147      * instruction is a no-op */
1148     return msg == DBELL_TYPE_DBELL_SERVER ? PPC_INTERRUPT_HDOORBELL : -1;
1149 }
1150 
1151 void helper_book3s_msgclr(CPUPPCState *env, target_ulong rb)
1152 {
1153     int irq = book3s_dbell2irq(rb);
1154 
1155     if (irq < 0) {
1156         return;
1157     }
1158 
1159     env->pending_interrupts &= ~(1 << irq);
1160 }
1161 
1162 void helper_book3s_msgsnd(target_ulong rb)
1163 {
1164     int irq = book3s_dbell2irq(rb);
1165     int pir = rb & DBELL_PROCIDTAG_MASK;
1166     CPUState *cs;
1167 
1168     if (irq < 0) {
1169         return;
1170     }
1171 
1172     qemu_mutex_lock_iothread();
1173     CPU_FOREACH(cs) {
1174         PowerPCCPU *cpu = POWERPC_CPU(cs);
1175         CPUPPCState *cenv = &cpu->env;
1176 
1177         /* TODO: broadcast message to all threads of the same  processor */
1178         if (cenv->spr_cb[SPR_PIR].default_value == pir) {
1179             cenv->pending_interrupts |= 1 << irq;
1180             cpu_interrupt(cs, CPU_INTERRUPT_HARD);
1181         }
1182     }
1183     qemu_mutex_unlock_iothread();
1184 }
1185 #endif
1186 
1187 void ppc_cpu_do_unaligned_access(CPUState *cs, vaddr vaddr,
1188                                  MMUAccessType access_type,
1189                                  int mmu_idx, uintptr_t retaddr)
1190 {
1191     CPUPPCState *env = cs->env_ptr;
1192     uint32_t insn;
1193 
1194     /* Restore state and reload the insn we executed, for filling in DSISR.  */
1195     cpu_restore_state(cs, retaddr, true);
1196     insn = cpu_ldl_code(env, env->nip);
1197 
1198     cs->exception_index = POWERPC_EXCP_ALIGN;
1199     env->error_code = insn & 0x03FF0000;
1200     cpu_loop_exit(cs);
1201 }
1202