xref: /openbmc/qemu/target/m68k/op_helper.c (revision ab0c7fb2)
1 /*
2  *  M68K helper routines
3  *
4  *  Copyright (c) 2007 CodeSourcery
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 2.1 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/log.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 "semihosting/semihost.h"
26 
27 #if !defined(CONFIG_USER_ONLY)
28 
29 static void cf_rte(CPUM68KState *env)
30 {
31     uint32_t sp;
32     uint32_t fmt;
33 
34     sp = env->aregs[7];
35     fmt = cpu_ldl_mmuidx_ra(env, sp, MMU_KERNEL_IDX, 0);
36     env->pc = cpu_ldl_mmuidx_ra(env, sp + 4, MMU_KERNEL_IDX, 0);
37     sp |= (fmt >> 28) & 3;
38     env->aregs[7] = sp + 8;
39 
40     cpu_m68k_set_sr(env, fmt);
41 }
42 
43 static void m68k_rte(CPUM68KState *env)
44 {
45     uint32_t sp;
46     uint16_t fmt;
47     uint16_t sr;
48 
49     sp = env->aregs[7];
50 throwaway:
51     sr = cpu_lduw_mmuidx_ra(env, sp, MMU_KERNEL_IDX, 0);
52     sp += 2;
53     env->pc = cpu_ldl_mmuidx_ra(env, sp, MMU_KERNEL_IDX, 0);
54     sp += 4;
55     if (m68k_feature(env, M68K_FEATURE_EXCEPTION_FORMAT_VEC)) {
56         /*  all except 68000 */
57         fmt = cpu_lduw_mmuidx_ra(env, sp, MMU_KERNEL_IDX, 0);
58         sp += 2;
59         switch (fmt >> 12) {
60         case 0:
61             break;
62         case 1:
63             env->aregs[7] = sp;
64             cpu_m68k_set_sr(env, sr);
65             goto throwaway;
66         case 2:
67         case 3:
68             sp += 4;
69             break;
70         case 4:
71             sp += 8;
72             break;
73         case 7:
74             sp += 52;
75             break;
76         }
77     }
78     env->aregs[7] = sp;
79     cpu_m68k_set_sr(env, sr);
80 }
81 
82 static const char *m68k_exception_name(int index)
83 {
84     switch (index) {
85     case EXCP_ACCESS:
86         return "Access Fault";
87     case EXCP_ADDRESS:
88         return "Address Error";
89     case EXCP_ILLEGAL:
90         return "Illegal Instruction";
91     case EXCP_DIV0:
92         return "Divide by Zero";
93     case EXCP_CHK:
94         return "CHK/CHK2";
95     case EXCP_TRAPCC:
96         return "FTRAPcc, TRAPcc, TRAPV";
97     case EXCP_PRIVILEGE:
98         return "Privilege Violation";
99     case EXCP_TRACE:
100         return "Trace";
101     case EXCP_LINEA:
102         return "A-Line";
103     case EXCP_LINEF:
104         return "F-Line";
105     case EXCP_DEBEGBP: /* 68020/030 only */
106         return "Copro Protocol Violation";
107     case EXCP_FORMAT:
108         return "Format Error";
109     case EXCP_UNINITIALIZED:
110         return "Uninitialized Interrupt";
111     case EXCP_SPURIOUS:
112         return "Spurious Interrupt";
113     case EXCP_INT_LEVEL_1:
114         return "Level 1 Interrupt";
115     case EXCP_INT_LEVEL_1 + 1:
116         return "Level 2 Interrupt";
117     case EXCP_INT_LEVEL_1 + 2:
118         return "Level 3 Interrupt";
119     case EXCP_INT_LEVEL_1 + 3:
120         return "Level 4 Interrupt";
121     case EXCP_INT_LEVEL_1 + 4:
122         return "Level 5 Interrupt";
123     case EXCP_INT_LEVEL_1 + 5:
124         return "Level 6 Interrupt";
125     case EXCP_INT_LEVEL_1 + 6:
126         return "Level 7 Interrupt";
127     case EXCP_TRAP0:
128         return "TRAP #0";
129     case EXCP_TRAP0 + 1:
130         return "TRAP #1";
131     case EXCP_TRAP0 + 2:
132         return "TRAP #2";
133     case EXCP_TRAP0 + 3:
134         return "TRAP #3";
135     case EXCP_TRAP0 + 4:
136         return "TRAP #4";
137     case EXCP_TRAP0 + 5:
138         return "TRAP #5";
139     case EXCP_TRAP0 + 6:
140         return "TRAP #6";
141     case EXCP_TRAP0 + 7:
142         return "TRAP #7";
143     case EXCP_TRAP0 + 8:
144         return "TRAP #8";
145     case EXCP_TRAP0 + 9:
146         return "TRAP #9";
147     case EXCP_TRAP0 + 10:
148         return "TRAP #10";
149     case EXCP_TRAP0 + 11:
150         return "TRAP #11";
151     case EXCP_TRAP0 + 12:
152         return "TRAP #12";
153     case EXCP_TRAP0 + 13:
154         return "TRAP #13";
155     case EXCP_TRAP0 + 14:
156         return "TRAP #14";
157     case EXCP_TRAP0 + 15:
158         return "TRAP #15";
159     case EXCP_FP_BSUN:
160         return "FP Branch/Set on unordered condition";
161     case EXCP_FP_INEX:
162         return "FP Inexact Result";
163     case EXCP_FP_DZ:
164         return "FP Divide by Zero";
165     case EXCP_FP_UNFL:
166         return "FP Underflow";
167     case EXCP_FP_OPERR:
168         return "FP Operand Error";
169     case EXCP_FP_OVFL:
170         return "FP Overflow";
171     case EXCP_FP_SNAN:
172         return "FP Signaling NAN";
173     case EXCP_FP_UNIMP:
174         return "FP Unimplemented Data Type";
175     case EXCP_MMU_CONF: /* 68030/68851 only */
176         return "MMU Configuration Error";
177     case EXCP_MMU_ILLEGAL: /* 68851 only */
178         return "MMU Illegal Operation";
179     case EXCP_MMU_ACCESS: /* 68851 only */
180         return "MMU Access Level Violation";
181     case 64 ... 255:
182         return "User Defined Vector";
183     }
184     return "Unassigned";
185 }
186 
187 static void cf_interrupt_all(CPUM68KState *env, int is_hw)
188 {
189     CPUState *cs = env_cpu(env);
190     uint32_t sp;
191     uint32_t sr;
192     uint32_t fmt;
193     uint32_t retaddr;
194     uint32_t vector;
195 
196     fmt = 0;
197     retaddr = env->pc;
198 
199     if (!is_hw) {
200         switch (cs->exception_index) {
201         case EXCP_RTE:
202             /* Return from an exception.  */
203             cf_rte(env);
204             return;
205         case EXCP_HALT_INSN:
206             if (semihosting_enabled((env->sr & SR_S) == 0)
207                     && (env->pc & 3) == 0
208                     && cpu_lduw_code(env, env->pc - 4) == 0x4e71
209                     && cpu_ldl_code(env, env->pc) == 0x4e7bf000) {
210                 env->pc += 4;
211                 do_m68k_semihosting(env, env->dregs[0]);
212                 return;
213             }
214             cs->halted = 1;
215             cs->exception_index = EXCP_HLT;
216             cpu_loop_exit(cs);
217             return;
218         }
219     }
220 
221     vector = cs->exception_index << 2;
222 
223     sr = env->sr | cpu_m68k_get_ccr(env);
224     if (qemu_loglevel_mask(CPU_LOG_INT)) {
225         static int count;
226         qemu_log("INT %6d: %s(%#x) pc=%08x sp=%08x sr=%04x\n",
227                  ++count, m68k_exception_name(cs->exception_index),
228                  vector, env->pc, env->aregs[7], sr);
229     }
230 
231     fmt |= 0x40000000;
232     fmt |= vector << 16;
233     fmt |= sr;
234 
235     env->sr |= SR_S;
236     if (is_hw) {
237         env->sr = (env->sr & ~SR_I) | (env->pending_level << SR_I_SHIFT);
238         env->sr &= ~SR_M;
239     }
240     m68k_switch_sp(env);
241     sp = env->aregs[7];
242     fmt |= (sp & 3) << 28;
243 
244     /* ??? This could cause MMU faults.  */
245     sp &= ~3;
246     sp -= 4;
247     cpu_stl_mmuidx_ra(env, sp, retaddr, MMU_KERNEL_IDX, 0);
248     sp -= 4;
249     cpu_stl_mmuidx_ra(env, sp, fmt, MMU_KERNEL_IDX, 0);
250     env->aregs[7] = sp;
251     /* Jump to vector.  */
252     env->pc = cpu_ldl_mmuidx_ra(env, env->vbr + vector, MMU_KERNEL_IDX, 0);
253 }
254 
255 static inline void do_stack_frame(CPUM68KState *env, uint32_t *sp,
256                                   uint16_t format, uint16_t sr,
257                                   uint32_t addr, uint32_t retaddr)
258 {
259     if (m68k_feature(env, M68K_FEATURE_EXCEPTION_FORMAT_VEC)) {
260         /*  all except 68000 */
261         CPUState *cs = env_cpu(env);
262         switch (format) {
263         case 4:
264             *sp -= 4;
265             cpu_stl_mmuidx_ra(env, *sp, env->pc, MMU_KERNEL_IDX, 0);
266             *sp -= 4;
267             cpu_stl_mmuidx_ra(env, *sp, addr, MMU_KERNEL_IDX, 0);
268             break;
269         case 3:
270         case 2:
271             *sp -= 4;
272             cpu_stl_mmuidx_ra(env, *sp, addr, MMU_KERNEL_IDX, 0);
273             break;
274         }
275         *sp -= 2;
276         cpu_stw_mmuidx_ra(env, *sp, (format << 12) + (cs->exception_index << 2),
277                           MMU_KERNEL_IDX, 0);
278     }
279     *sp -= 4;
280     cpu_stl_mmuidx_ra(env, *sp, retaddr, MMU_KERNEL_IDX, 0);
281     *sp -= 2;
282     cpu_stw_mmuidx_ra(env, *sp, sr, MMU_KERNEL_IDX, 0);
283 }
284 
285 static void m68k_interrupt_all(CPUM68KState *env, int is_hw)
286 {
287     CPUState *cs = env_cpu(env);
288     uint32_t sp;
289     uint32_t vector;
290     uint16_t sr, oldsr;
291 
292     if (!is_hw) {
293         switch (cs->exception_index) {
294         case EXCP_RTE:
295             /* Return from an exception.  */
296             m68k_rte(env);
297             return;
298         }
299     }
300 
301     vector = cs->exception_index << 2;
302 
303     sr = env->sr | cpu_m68k_get_ccr(env);
304     if (qemu_loglevel_mask(CPU_LOG_INT)) {
305         static int count;
306         qemu_log("INT %6d: %s(%#x) pc=%08x sp=%08x sr=%04x\n",
307                  ++count, m68k_exception_name(cs->exception_index),
308                  vector, env->pc, env->aregs[7], sr);
309     }
310 
311     /*
312      * MC68040UM/AD,  chapter 9.3.10
313      */
314 
315     /* "the processor first make an internal copy" */
316     oldsr = sr;
317     /* "set the mode to supervisor" */
318     sr |= SR_S;
319     /* "suppress tracing" */
320     sr &= ~SR_T;
321     /* "sets the processor interrupt mask" */
322     if (is_hw) {
323         sr |= (env->sr & ~SR_I) | (env->pending_level << SR_I_SHIFT);
324     }
325     cpu_m68k_set_sr(env, sr);
326     sp = env->aregs[7];
327 
328     if (!m68k_feature(env, M68K_FEATURE_UNALIGNED_DATA)) {
329         sp &= ~1;
330     }
331 
332     switch (cs->exception_index) {
333     case EXCP_ACCESS:
334         if (env->mmu.fault) {
335             cpu_abort(cs, "DOUBLE MMU FAULT\n");
336         }
337         env->mmu.fault = true;
338         /* push data 3 */
339         sp -= 4;
340         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
341         /* push data 2 */
342         sp -= 4;
343         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
344         /* push data 1 */
345         sp -= 4;
346         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
347         /* write back 1 / push data 0 */
348         sp -= 4;
349         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
350         /* write back 1 address */
351         sp -= 4;
352         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
353         /* write back 2 data */
354         sp -= 4;
355         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
356         /* write back 2 address */
357         sp -= 4;
358         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
359         /* write back 3 data */
360         sp -= 4;
361         cpu_stl_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
362         /* write back 3 address */
363         sp -= 4;
364         cpu_stl_mmuidx_ra(env, sp, env->mmu.ar, MMU_KERNEL_IDX, 0);
365         /* fault address */
366         sp -= 4;
367         cpu_stl_mmuidx_ra(env, sp, env->mmu.ar, MMU_KERNEL_IDX, 0);
368         /* write back 1 status */
369         sp -= 2;
370         cpu_stw_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
371         /* write back 2 status */
372         sp -= 2;
373         cpu_stw_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
374         /* write back 3 status */
375         sp -= 2;
376         cpu_stw_mmuidx_ra(env, sp, 0, MMU_KERNEL_IDX, 0);
377         /* special status word */
378         sp -= 2;
379         cpu_stw_mmuidx_ra(env, sp, env->mmu.ssw, MMU_KERNEL_IDX, 0);
380         /* effective address */
381         sp -= 4;
382         cpu_stl_mmuidx_ra(env, sp, env->mmu.ar, MMU_KERNEL_IDX, 0);
383 
384         do_stack_frame(env, &sp, 7, oldsr, 0, env->pc);
385         env->mmu.fault = false;
386         if (qemu_loglevel_mask(CPU_LOG_INT)) {
387             qemu_log("            "
388                      "ssw:  %08x ea:   %08x sfc:  %d    dfc: %d\n",
389                      env->mmu.ssw, env->mmu.ar, env->sfc, env->dfc);
390         }
391         break;
392 
393     case EXCP_ILLEGAL:
394         do_stack_frame(env, &sp, 0, oldsr, 0, env->pc);
395         break;
396 
397     case EXCP_ADDRESS:
398         do_stack_frame(env, &sp, 2, oldsr, 0, env->pc);
399         break;
400 
401     case EXCP_CHK:
402     case EXCP_DIV0:
403     case EXCP_TRACE:
404     case EXCP_TRAPCC:
405         do_stack_frame(env, &sp, 2, oldsr, env->mmu.ar, env->pc);
406         break;
407 
408     case EXCP_SPURIOUS ... EXCP_INT_LEVEL_7:
409         if (is_hw && (oldsr & SR_M)) {
410             do_stack_frame(env, &sp, 0, oldsr, 0, env->pc);
411             oldsr = sr;
412             env->aregs[7] = sp;
413             cpu_m68k_set_sr(env, sr & ~SR_M);
414             sp = env->aregs[7];
415             if (!m68k_feature(env, M68K_FEATURE_UNALIGNED_DATA)) {
416                 sp &= ~1;
417             }
418             do_stack_frame(env, &sp, 1, oldsr, 0, env->pc);
419             break;
420         }
421         /* fall through */
422 
423     default:
424         do_stack_frame(env, &sp, 0, oldsr, 0, env->pc);
425         break;
426     }
427 
428     env->aregs[7] = sp;
429     /* Jump to vector.  */
430     env->pc = cpu_ldl_mmuidx_ra(env, env->vbr + vector, MMU_KERNEL_IDX, 0);
431 }
432 
433 static void do_interrupt_all(CPUM68KState *env, int is_hw)
434 {
435     if (m68k_feature(env, M68K_FEATURE_M68K)) {
436         m68k_interrupt_all(env, is_hw);
437         return;
438     }
439     cf_interrupt_all(env, is_hw);
440 }
441 
442 void m68k_cpu_do_interrupt(CPUState *cs)
443 {
444     do_interrupt_all(cpu_env(cs), 0);
445 }
446 
447 static inline void do_interrupt_m68k_hardirq(CPUM68KState *env)
448 {
449     do_interrupt_all(env, 1);
450 }
451 
452 void m68k_cpu_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr,
453                                  unsigned size, MMUAccessType access_type,
454                                  int mmu_idx, MemTxAttrs attrs,
455                                  MemTxResult response, uintptr_t retaddr)
456 {
457     CPUM68KState *env = cpu_env(cs);
458 
459     cpu_restore_state(cs, retaddr);
460 
461     if (m68k_feature(env, M68K_FEATURE_M68040)) {
462         env->mmu.mmusr = 0;
463 
464         /*
465          * According to the MC68040 users manual the ATC bit of the SSW is
466          * used to distinguish between ATC faults and physical bus errors.
467          * In the case of a bus error e.g. during nubus read from an empty
468          * slot this bit should not be set
469          */
470         if (response != MEMTX_DECODE_ERROR) {
471             env->mmu.ssw |= M68K_ATC_040;
472         }
473 
474         /* FIXME: manage MMU table access error */
475         env->mmu.ssw &= ~M68K_TM_040;
476         if (env->sr & SR_S) { /* SUPERVISOR */
477             env->mmu.ssw |= M68K_TM_040_SUPER;
478         }
479         if (access_type == MMU_INST_FETCH) { /* instruction or data */
480             env->mmu.ssw |= M68K_TM_040_CODE;
481         } else {
482             env->mmu.ssw |= M68K_TM_040_DATA;
483         }
484         env->mmu.ssw &= ~M68K_BA_SIZE_MASK;
485         switch (size) {
486         case 1:
487             env->mmu.ssw |= M68K_BA_SIZE_BYTE;
488             break;
489         case 2:
490             env->mmu.ssw |= M68K_BA_SIZE_WORD;
491             break;
492         case 4:
493             env->mmu.ssw |= M68K_BA_SIZE_LONG;
494             break;
495         }
496 
497         if (access_type != MMU_DATA_STORE) {
498             env->mmu.ssw |= M68K_RW_040;
499         }
500 
501         env->mmu.ar = addr;
502 
503         cs->exception_index = EXCP_ACCESS;
504         cpu_loop_exit(cs);
505     }
506 }
507 
508 bool m68k_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
509 {
510     CPUM68KState *env = cpu_env(cs);
511 
512     if (interrupt_request & CPU_INTERRUPT_HARD
513         && ((env->sr & SR_I) >> SR_I_SHIFT) < env->pending_level) {
514         /*
515          * Real hardware gets the interrupt vector via an IACK cycle
516          * at this point.  Current emulated hardware doesn't rely on
517          * this, so we provide/save the vector when the interrupt is
518          * first signalled.
519          */
520         cs->exception_index = env->pending_vector;
521         do_interrupt_m68k_hardirq(env);
522         return true;
523     }
524     return false;
525 }
526 
527 #endif /* !CONFIG_USER_ONLY */
528 
529 G_NORETURN static void
530 raise_exception_ra(CPUM68KState *env, int tt, uintptr_t raddr)
531 {
532     CPUState *cs = env_cpu(env);
533 
534     cs->exception_index = tt;
535     cpu_loop_exit_restore(cs, raddr);
536 }
537 
538 G_NORETURN static void raise_exception(CPUM68KState *env, int tt)
539 {
540     raise_exception_ra(env, tt, 0);
541 }
542 
543 void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt)
544 {
545     raise_exception(env, tt);
546 }
547 
548 G_NORETURN static void
549 raise_exception_format2(CPUM68KState *env, int tt, int ilen, uintptr_t raddr)
550 {
551     CPUState *cs = env_cpu(env);
552 
553     cs->exception_index = tt;
554 
555     /* Recover PC and CC_OP for the beginning of the insn.  */
556     cpu_restore_state(cs, raddr);
557 
558     /* Flags are current in env->cc_*, or are undefined. */
559     env->cc_op = CC_OP_FLAGS;
560 
561     /*
562      * Remember original pc in mmu.ar, for the Format 2 stack frame.
563      * Adjust PC to end of the insn.
564      */
565     env->mmu.ar = env->pc;
566     env->pc += ilen;
567 
568     cpu_loop_exit(cs);
569 }
570 
571 void HELPER(divuw)(CPUM68KState *env, int destr, uint32_t den, int ilen)
572 {
573     uint32_t num = env->dregs[destr];
574     uint32_t quot, rem;
575 
576     env->cc_c = 0; /* always cleared, even if div0 */
577 
578     if (den == 0) {
579         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
580     }
581     quot = num / den;
582     rem = num % den;
583 
584     if (quot > 0xffff) {
585         env->cc_v = -1;
586         /*
587          * real 68040 keeps N and unset Z on overflow,
588          * whereas documentation says "undefined"
589          */
590         env->cc_z = 1;
591         return;
592     }
593     env->dregs[destr] = deposit32(quot, 16, 16, rem);
594     env->cc_z = (int16_t)quot;
595     env->cc_n = (int16_t)quot;
596     env->cc_v = 0;
597 }
598 
599 void HELPER(divsw)(CPUM68KState *env, int destr, int32_t den, int ilen)
600 {
601     int32_t num = env->dregs[destr];
602     uint32_t quot, rem;
603 
604     env->cc_c = 0; /* always cleared, even if overflow/div0 */
605 
606     if (den == 0) {
607         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
608     }
609     quot = num / den;
610     rem = num % den;
611 
612     if (quot != (int16_t)quot) {
613         env->cc_v = -1;
614         /* nothing else is modified */
615         /*
616          * real 68040 keeps N and unset Z on overflow,
617          * whereas documentation says "undefined"
618          */
619         env->cc_z = 1;
620         return;
621     }
622     env->dregs[destr] = deposit32(quot, 16, 16, rem);
623     env->cc_z = (int16_t)quot;
624     env->cc_n = (int16_t)quot;
625     env->cc_v = 0;
626 }
627 
628 void HELPER(divul)(CPUM68KState *env, int numr, int regr,
629                    uint32_t den, int ilen)
630 {
631     uint32_t num = env->dregs[numr];
632     uint32_t quot, rem;
633 
634     env->cc_c = 0; /* always cleared, even if div0 */
635 
636     if (den == 0) {
637         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
638     }
639     quot = num / den;
640     rem = num % den;
641 
642     env->cc_z = quot;
643     env->cc_n = quot;
644     env->cc_v = 0;
645 
646     if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {
647         if (numr == regr) {
648             env->dregs[numr] = quot;
649         } else {
650             env->dregs[regr] = rem;
651         }
652     } else {
653         env->dregs[regr] = rem;
654         env->dregs[numr] = quot;
655     }
656 }
657 
658 void HELPER(divsl)(CPUM68KState *env, int numr, int regr,
659                    int32_t den, int ilen)
660 {
661     int32_t num = env->dregs[numr];
662     int32_t quot, rem;
663 
664     env->cc_c = 0; /* always cleared, even if overflow/div0 */
665 
666     if (den == 0) {
667         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
668     }
669     quot = num / den;
670     rem = num % den;
671 
672     env->cc_z = quot;
673     env->cc_n = quot;
674     env->cc_v = 0;
675 
676     if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {
677         if (numr == regr) {
678             env->dregs[numr] = quot;
679         } else {
680             env->dregs[regr] = rem;
681         }
682     } else {
683         env->dregs[regr] = rem;
684         env->dregs[numr] = quot;
685     }
686 }
687 
688 void HELPER(divull)(CPUM68KState *env, int numr, int regr,
689                     uint32_t den, int ilen)
690 {
691     uint64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);
692     uint64_t quot;
693     uint32_t rem;
694 
695     env->cc_c = 0; /* always cleared, even if overflow/div0 */
696 
697     if (den == 0) {
698         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
699     }
700     quot = num / den;
701     rem = num % den;
702 
703     if (quot > 0xffffffffULL) {
704         env->cc_v = -1;
705         /*
706          * real 68040 keeps N and unset Z on overflow,
707          * whereas documentation says "undefined"
708          */
709         env->cc_z = 1;
710         return;
711     }
712     env->cc_z = quot;
713     env->cc_n = quot;
714     env->cc_v = 0;
715 
716     /*
717      * If Dq and Dr are the same, the quotient is returned.
718      * therefore we set Dq last.
719      */
720 
721     env->dregs[regr] = rem;
722     env->dregs[numr] = quot;
723 }
724 
725 void HELPER(divsll)(CPUM68KState *env, int numr, int regr,
726                     int32_t den, int ilen)
727 {
728     int64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);
729     int64_t quot;
730     int32_t rem;
731 
732     env->cc_c = 0; /* always cleared, even if overflow/div0 */
733 
734     if (den == 0) {
735         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
736     }
737     quot = num / den;
738     rem = num % den;
739 
740     if (quot != (int32_t)quot) {
741         env->cc_v = -1;
742         /*
743          * real 68040 keeps N and unset Z on overflow,
744          * whereas documentation says "undefined"
745          */
746         env->cc_z = 1;
747         return;
748     }
749     env->cc_z = quot;
750     env->cc_n = quot;
751     env->cc_v = 0;
752 
753     /*
754      * If Dq and Dr are the same, the quotient is returned.
755      * therefore we set Dq last.
756      */
757 
758     env->dregs[regr] = rem;
759     env->dregs[numr] = quot;
760 }
761 
762 /* We're executing in a serial context -- no need to be atomic.  */
763 void HELPER(cas2w)(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2)
764 {
765     uint32_t Dc1 = extract32(regs, 9, 3);
766     uint32_t Dc2 = extract32(regs, 6, 3);
767     uint32_t Du1 = extract32(regs, 3, 3);
768     uint32_t Du2 = extract32(regs, 0, 3);
769     int16_t c1 = env->dregs[Dc1];
770     int16_t c2 = env->dregs[Dc2];
771     int16_t u1 = env->dregs[Du1];
772     int16_t u2 = env->dregs[Du2];
773     int16_t l1, l2;
774     uintptr_t ra = GETPC();
775 
776     l1 = cpu_lduw_data_ra(env, a1, ra);
777     l2 = cpu_lduw_data_ra(env, a2, ra);
778     if (l1 == c1 && l2 == c2) {
779         cpu_stw_data_ra(env, a1, u1, ra);
780         cpu_stw_data_ra(env, a2, u2, ra);
781     }
782 
783     if (c1 != l1) {
784         env->cc_n = l1;
785         env->cc_v = c1;
786     } else {
787         env->cc_n = l2;
788         env->cc_v = c2;
789     }
790     env->cc_op = CC_OP_CMPW;
791     env->dregs[Dc1] = deposit32(env->dregs[Dc1], 0, 16, l1);
792     env->dregs[Dc2] = deposit32(env->dregs[Dc2], 0, 16, l2);
793 }
794 
795 static void do_cas2l(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2,
796                      bool parallel)
797 {
798     uint32_t Dc1 = extract32(regs, 9, 3);
799     uint32_t Dc2 = extract32(regs, 6, 3);
800     uint32_t Du1 = extract32(regs, 3, 3);
801     uint32_t Du2 = extract32(regs, 0, 3);
802     uint32_t c1 = env->dregs[Dc1];
803     uint32_t c2 = env->dregs[Dc2];
804     uint32_t u1 = env->dregs[Du1];
805     uint32_t u2 = env->dregs[Du2];
806     uint32_t l1, l2;
807     uintptr_t ra = GETPC();
808 #if defined(CONFIG_ATOMIC64)
809     int mmu_idx = cpu_mmu_index(env_cpu(env), 0);
810     MemOpIdx oi = make_memop_idx(MO_BEUQ, mmu_idx);
811 #endif
812 
813     if (parallel) {
814         /* We're executing in a parallel context -- must be atomic.  */
815 #ifdef CONFIG_ATOMIC64
816         uint64_t c, u, l;
817         if ((a1 & 7) == 0 && a2 == a1 + 4) {
818             c = deposit64(c2, 32, 32, c1);
819             u = deposit64(u2, 32, 32, u1);
820             l = cpu_atomic_cmpxchgq_be_mmu(env, a1, c, u, oi, ra);
821             l1 = l >> 32;
822             l2 = l;
823         } else if ((a2 & 7) == 0 && a1 == a2 + 4) {
824             c = deposit64(c1, 32, 32, c2);
825             u = deposit64(u1, 32, 32, u2);
826             l = cpu_atomic_cmpxchgq_be_mmu(env, a2, c, u, oi, ra);
827             l2 = l >> 32;
828             l1 = l;
829         } else
830 #endif
831         {
832             /* Tell the main loop we need to serialize this insn.  */
833             cpu_loop_exit_atomic(env_cpu(env), ra);
834         }
835     } else {
836         /* We're executing in a serial context -- no need to be atomic.  */
837         l1 = cpu_ldl_data_ra(env, a1, ra);
838         l2 = cpu_ldl_data_ra(env, a2, ra);
839         if (l1 == c1 && l2 == c2) {
840             cpu_stl_data_ra(env, a1, u1, ra);
841             cpu_stl_data_ra(env, a2, u2, ra);
842         }
843     }
844 
845     if (c1 != l1) {
846         env->cc_n = l1;
847         env->cc_v = c1;
848     } else {
849         env->cc_n = l2;
850         env->cc_v = c2;
851     }
852     env->cc_op = CC_OP_CMPL;
853     env->dregs[Dc1] = l1;
854     env->dregs[Dc2] = l2;
855 }
856 
857 void HELPER(cas2l)(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2)
858 {
859     do_cas2l(env, regs, a1, a2, false);
860 }
861 
862 void HELPER(cas2l_parallel)(CPUM68KState *env, uint32_t regs, uint32_t a1,
863                             uint32_t a2)
864 {
865     do_cas2l(env, regs, a1, a2, true);
866 }
867 
868 struct bf_data {
869     uint32_t addr;
870     uint32_t bofs;
871     uint32_t blen;
872     uint32_t len;
873 };
874 
875 static struct bf_data bf_prep(uint32_t addr, int32_t ofs, uint32_t len)
876 {
877     int bofs, blen;
878 
879     /* Bound length; map 0 to 32.  */
880     len = ((len - 1) & 31) + 1;
881 
882     /* Note that ofs is signed.  */
883     addr += ofs / 8;
884     bofs = ofs % 8;
885     if (bofs < 0) {
886         bofs += 8;
887         addr -= 1;
888     }
889 
890     /*
891      * Compute the number of bytes required (minus one) to
892      * satisfy the bitfield.
893      */
894     blen = (bofs + len - 1) / 8;
895 
896     /*
897      * Canonicalize the bit offset for data loaded into a 64-bit big-endian
898      * word.  For the cases where BLEN is not a power of 2, adjust ADDR so
899      * that we can use the next power of two sized load without crossing a
900      * page boundary, unless the field itself crosses the boundary.
901      */
902     switch (blen) {
903     case 0:
904         bofs += 56;
905         break;
906     case 1:
907         bofs += 48;
908         break;
909     case 2:
910         if (addr & 1) {
911             bofs += 8;
912             addr -= 1;
913         }
914         /* fallthru */
915     case 3:
916         bofs += 32;
917         break;
918     case 4:
919         if (addr & 3) {
920             bofs += 8 * (addr & 3);
921             addr &= -4;
922         }
923         break;
924     default:
925         g_assert_not_reached();
926     }
927 
928     return (struct bf_data){
929         .addr = addr,
930         .bofs = bofs,
931         .blen = blen,
932         .len = len,
933     };
934 }
935 
936 static uint64_t bf_load(CPUM68KState *env, uint32_t addr, int blen,
937                         uintptr_t ra)
938 {
939     switch (blen) {
940     case 0:
941         return cpu_ldub_data_ra(env, addr, ra);
942     case 1:
943         return cpu_lduw_data_ra(env, addr, ra);
944     case 2:
945     case 3:
946         return cpu_ldl_data_ra(env, addr, ra);
947     case 4:
948         return cpu_ldq_data_ra(env, addr, ra);
949     default:
950         g_assert_not_reached();
951     }
952 }
953 
954 static void bf_store(CPUM68KState *env, uint32_t addr, int blen,
955                      uint64_t data, uintptr_t ra)
956 {
957     switch (blen) {
958     case 0:
959         cpu_stb_data_ra(env, addr, data, ra);
960         break;
961     case 1:
962         cpu_stw_data_ra(env, addr, data, ra);
963         break;
964     case 2:
965     case 3:
966         cpu_stl_data_ra(env, addr, data, ra);
967         break;
968     case 4:
969         cpu_stq_data_ra(env, addr, data, ra);
970         break;
971     default:
972         g_assert_not_reached();
973     }
974 }
975 
976 uint32_t HELPER(bfexts_mem)(CPUM68KState *env, uint32_t addr,
977                             int32_t ofs, uint32_t len)
978 {
979     uintptr_t ra = GETPC();
980     struct bf_data d = bf_prep(addr, ofs, len);
981     uint64_t data = bf_load(env, d.addr, d.blen, ra);
982 
983     return (int64_t)(data << d.bofs) >> (64 - d.len);
984 }
985 
986 uint64_t HELPER(bfextu_mem)(CPUM68KState *env, uint32_t addr,
987                             int32_t ofs, uint32_t len)
988 {
989     uintptr_t ra = GETPC();
990     struct bf_data d = bf_prep(addr, ofs, len);
991     uint64_t data = bf_load(env, d.addr, d.blen, ra);
992 
993     /*
994      * Put CC_N at the top of the high word; put the zero-extended value
995      * at the bottom of the low word.
996      */
997     data <<= d.bofs;
998     data >>= 64 - d.len;
999     data |= data << (64 - d.len);
1000 
1001     return data;
1002 }
1003 
1004 uint32_t HELPER(bfins_mem)(CPUM68KState *env, uint32_t addr, uint32_t val,
1005                            int32_t ofs, uint32_t len)
1006 {
1007     uintptr_t ra = GETPC();
1008     struct bf_data d = bf_prep(addr, ofs, len);
1009     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1010     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1011 
1012     data = (data & ~mask) | (((uint64_t)val << (64 - d.len)) >> d.bofs);
1013 
1014     bf_store(env, d.addr, d.blen, data, ra);
1015 
1016     /* The field at the top of the word is also CC_N for CC_OP_LOGIC.  */
1017     return val << (32 - d.len);
1018 }
1019 
1020 uint32_t HELPER(bfchg_mem)(CPUM68KState *env, uint32_t addr,
1021                            int32_t ofs, uint32_t len)
1022 {
1023     uintptr_t ra = GETPC();
1024     struct bf_data d = bf_prep(addr, ofs, len);
1025     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1026     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1027 
1028     bf_store(env, d.addr, d.blen, data ^ mask, ra);
1029 
1030     return ((data & mask) << d.bofs) >> 32;
1031 }
1032 
1033 uint32_t HELPER(bfclr_mem)(CPUM68KState *env, uint32_t addr,
1034                            int32_t ofs, uint32_t len)
1035 {
1036     uintptr_t ra = GETPC();
1037     struct bf_data d = bf_prep(addr, ofs, len);
1038     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1039     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1040 
1041     bf_store(env, d.addr, d.blen, data & ~mask, ra);
1042 
1043     return ((data & mask) << d.bofs) >> 32;
1044 }
1045 
1046 uint32_t HELPER(bfset_mem)(CPUM68KState *env, uint32_t addr,
1047                            int32_t ofs, uint32_t len)
1048 {
1049     uintptr_t ra = GETPC();
1050     struct bf_data d = bf_prep(addr, ofs, len);
1051     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1052     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1053 
1054     bf_store(env, d.addr, d.blen, data | mask, ra);
1055 
1056     return ((data & mask) << d.bofs) >> 32;
1057 }
1058 
1059 uint32_t HELPER(bfffo_reg)(uint32_t n, uint32_t ofs, uint32_t len)
1060 {
1061     return (n ? clz32(n) : len) + ofs;
1062 }
1063 
1064 uint64_t HELPER(bfffo_mem)(CPUM68KState *env, uint32_t addr,
1065                            int32_t ofs, uint32_t len)
1066 {
1067     uintptr_t ra = GETPC();
1068     struct bf_data d = bf_prep(addr, ofs, len);
1069     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1070     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1071     uint64_t n = (data & mask) << d.bofs;
1072     uint32_t ffo = helper_bfffo_reg(n >> 32, ofs, d.len);
1073 
1074     /*
1075      * Return FFO in the low word and N in the high word.
1076      * Note that because of MASK and the shift, the low word
1077      * is already zero.
1078      */
1079     return n | ffo;
1080 }
1081 
1082 void HELPER(chk)(CPUM68KState *env, int32_t val, int32_t ub)
1083 {
1084     /*
1085      * From the specs:
1086      *   X: Not affected, C,V,Z: Undefined,
1087      *   N: Set if val < 0; cleared if val > ub, undefined otherwise
1088      * We implement here values found from a real MC68040:
1089      *   X,V,Z: Not affected
1090      *   N: Set if val < 0; cleared if val >= 0
1091      *   C: if 0 <= ub: set if val < 0 or val > ub, cleared otherwise
1092      *      if 0 > ub: set if val > ub and val < 0, cleared otherwise
1093      */
1094     env->cc_n = val;
1095     env->cc_c = 0 <= ub ? val < 0 || val > ub : val > ub && val < 0;
1096 
1097     if (val < 0 || val > ub) {
1098         raise_exception_format2(env, EXCP_CHK, 2, GETPC());
1099     }
1100 }
1101 
1102 void HELPER(chk2)(CPUM68KState *env, int32_t val, int32_t lb, int32_t ub)
1103 {
1104     /*
1105      * From the specs:
1106      *   X: Not affected, N,V: Undefined,
1107      *   Z: Set if val is equal to lb or ub
1108      *   C: Set if val < lb or val > ub, cleared otherwise
1109      * We implement here values found from a real MC68040:
1110      *   X,N,V: Not affected
1111      *   Z: Set if val is equal to lb or ub
1112      *   C: if lb <= ub: set if val < lb or val > ub, cleared otherwise
1113      *      if lb > ub: set if val > ub and val < lb, cleared otherwise
1114      */
1115     env->cc_z = val != lb && val != ub;
1116     env->cc_c = lb <= ub ? val < lb || val > ub : val > ub && val < lb;
1117 
1118     if (env->cc_c) {
1119         raise_exception_format2(env, EXCP_CHK, 4, GETPC());
1120     }
1121 }
1122