xref: /openbmc/qemu/target/m68k/op_helper.c (revision 735eee07)
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     M68kCPU *cpu = M68K_CPU(cs);
445     CPUM68KState *env = &cpu->env;
446 
447     do_interrupt_all(env, 0);
448 }
449 
450 static inline void do_interrupt_m68k_hardirq(CPUM68KState *env)
451 {
452     do_interrupt_all(env, 1);
453 }
454 
455 void m68k_cpu_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr,
456                                  unsigned size, MMUAccessType access_type,
457                                  int mmu_idx, MemTxAttrs attrs,
458                                  MemTxResult response, uintptr_t retaddr)
459 {
460     M68kCPU *cpu = M68K_CPU(cs);
461     CPUM68KState *env = &cpu->env;
462 
463     cpu_restore_state(cs, retaddr);
464 
465     if (m68k_feature(env, M68K_FEATURE_M68040)) {
466         env->mmu.mmusr = 0;
467 
468         /*
469          * According to the MC68040 users manual the ATC bit of the SSW is
470          * used to distinguish between ATC faults and physical bus errors.
471          * In the case of a bus error e.g. during nubus read from an empty
472          * slot this bit should not be set
473          */
474         if (response != MEMTX_DECODE_ERROR) {
475             env->mmu.ssw |= M68K_ATC_040;
476         }
477 
478         /* FIXME: manage MMU table access error */
479         env->mmu.ssw &= ~M68K_TM_040;
480         if (env->sr & SR_S) { /* SUPERVISOR */
481             env->mmu.ssw |= M68K_TM_040_SUPER;
482         }
483         if (access_type == MMU_INST_FETCH) { /* instruction or data */
484             env->mmu.ssw |= M68K_TM_040_CODE;
485         } else {
486             env->mmu.ssw |= M68K_TM_040_DATA;
487         }
488         env->mmu.ssw &= ~M68K_BA_SIZE_MASK;
489         switch (size) {
490         case 1:
491             env->mmu.ssw |= M68K_BA_SIZE_BYTE;
492             break;
493         case 2:
494             env->mmu.ssw |= M68K_BA_SIZE_WORD;
495             break;
496         case 4:
497             env->mmu.ssw |= M68K_BA_SIZE_LONG;
498             break;
499         }
500 
501         if (access_type != MMU_DATA_STORE) {
502             env->mmu.ssw |= M68K_RW_040;
503         }
504 
505         env->mmu.ar = addr;
506 
507         cs->exception_index = EXCP_ACCESS;
508         cpu_loop_exit(cs);
509     }
510 }
511 
512 bool m68k_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
513 {
514     M68kCPU *cpu = M68K_CPU(cs);
515     CPUM68KState *env = &cpu->env;
516 
517     if (interrupt_request & CPU_INTERRUPT_HARD
518         && ((env->sr & SR_I) >> SR_I_SHIFT) < env->pending_level) {
519         /*
520          * Real hardware gets the interrupt vector via an IACK cycle
521          * at this point.  Current emulated hardware doesn't rely on
522          * this, so we provide/save the vector when the interrupt is
523          * first signalled.
524          */
525         cs->exception_index = env->pending_vector;
526         do_interrupt_m68k_hardirq(env);
527         return true;
528     }
529     return false;
530 }
531 
532 #endif /* !CONFIG_USER_ONLY */
533 
534 G_NORETURN static void
535 raise_exception_ra(CPUM68KState *env, int tt, uintptr_t raddr)
536 {
537     CPUState *cs = env_cpu(env);
538 
539     cs->exception_index = tt;
540     cpu_loop_exit_restore(cs, raddr);
541 }
542 
543 G_NORETURN static void raise_exception(CPUM68KState *env, int tt)
544 {
545     raise_exception_ra(env, tt, 0);
546 }
547 
548 void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt)
549 {
550     raise_exception(env, tt);
551 }
552 
553 G_NORETURN static void
554 raise_exception_format2(CPUM68KState *env, int tt, int ilen, uintptr_t raddr)
555 {
556     CPUState *cs = env_cpu(env);
557 
558     cs->exception_index = tt;
559 
560     /* Recover PC and CC_OP for the beginning of the insn.  */
561     cpu_restore_state(cs, raddr);
562 
563     /* Flags are current in env->cc_*, or are undefined. */
564     env->cc_op = CC_OP_FLAGS;
565 
566     /*
567      * Remember original pc in mmu.ar, for the Format 2 stack frame.
568      * Adjust PC to end of the insn.
569      */
570     env->mmu.ar = env->pc;
571     env->pc += ilen;
572 
573     cpu_loop_exit(cs);
574 }
575 
576 void HELPER(divuw)(CPUM68KState *env, int destr, uint32_t den, int ilen)
577 {
578     uint32_t num = env->dregs[destr];
579     uint32_t quot, rem;
580 
581     env->cc_c = 0; /* always cleared, even if div0 */
582 
583     if (den == 0) {
584         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
585     }
586     quot = num / den;
587     rem = num % den;
588 
589     if (quot > 0xffff) {
590         env->cc_v = -1;
591         /*
592          * real 68040 keeps N and unset Z on overflow,
593          * whereas documentation says "undefined"
594          */
595         env->cc_z = 1;
596         return;
597     }
598     env->dregs[destr] = deposit32(quot, 16, 16, rem);
599     env->cc_z = (int16_t)quot;
600     env->cc_n = (int16_t)quot;
601     env->cc_v = 0;
602 }
603 
604 void HELPER(divsw)(CPUM68KState *env, int destr, int32_t den, int ilen)
605 {
606     int32_t num = env->dregs[destr];
607     uint32_t quot, rem;
608 
609     env->cc_c = 0; /* always cleared, even if overflow/div0 */
610 
611     if (den == 0) {
612         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
613     }
614     quot = num / den;
615     rem = num % den;
616 
617     if (quot != (int16_t)quot) {
618         env->cc_v = -1;
619         /* nothing else is modified */
620         /*
621          * real 68040 keeps N and unset Z on overflow,
622          * whereas documentation says "undefined"
623          */
624         env->cc_z = 1;
625         return;
626     }
627     env->dregs[destr] = deposit32(quot, 16, 16, rem);
628     env->cc_z = (int16_t)quot;
629     env->cc_n = (int16_t)quot;
630     env->cc_v = 0;
631 }
632 
633 void HELPER(divul)(CPUM68KState *env, int numr, int regr,
634                    uint32_t den, int ilen)
635 {
636     uint32_t num = env->dregs[numr];
637     uint32_t quot, rem;
638 
639     env->cc_c = 0; /* always cleared, even if div0 */
640 
641     if (den == 0) {
642         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
643     }
644     quot = num / den;
645     rem = num % den;
646 
647     env->cc_z = quot;
648     env->cc_n = quot;
649     env->cc_v = 0;
650 
651     if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {
652         if (numr == regr) {
653             env->dregs[numr] = quot;
654         } else {
655             env->dregs[regr] = rem;
656         }
657     } else {
658         env->dregs[regr] = rem;
659         env->dregs[numr] = quot;
660     }
661 }
662 
663 void HELPER(divsl)(CPUM68KState *env, int numr, int regr,
664                    int32_t den, int ilen)
665 {
666     int32_t num = env->dregs[numr];
667     int32_t quot, rem;
668 
669     env->cc_c = 0; /* always cleared, even if overflow/div0 */
670 
671     if (den == 0) {
672         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
673     }
674     quot = num / den;
675     rem = num % den;
676 
677     env->cc_z = quot;
678     env->cc_n = quot;
679     env->cc_v = 0;
680 
681     if (m68k_feature(env, M68K_FEATURE_CF_ISA_A)) {
682         if (numr == regr) {
683             env->dregs[numr] = quot;
684         } else {
685             env->dregs[regr] = rem;
686         }
687     } else {
688         env->dregs[regr] = rem;
689         env->dregs[numr] = quot;
690     }
691 }
692 
693 void HELPER(divull)(CPUM68KState *env, int numr, int regr,
694                     uint32_t den, int ilen)
695 {
696     uint64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);
697     uint64_t quot;
698     uint32_t rem;
699 
700     env->cc_c = 0; /* always cleared, even if overflow/div0 */
701 
702     if (den == 0) {
703         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
704     }
705     quot = num / den;
706     rem = num % den;
707 
708     if (quot > 0xffffffffULL) {
709         env->cc_v = -1;
710         /*
711          * real 68040 keeps N and unset Z on overflow,
712          * whereas documentation says "undefined"
713          */
714         env->cc_z = 1;
715         return;
716     }
717     env->cc_z = quot;
718     env->cc_n = quot;
719     env->cc_v = 0;
720 
721     /*
722      * If Dq and Dr are the same, the quotient is returned.
723      * therefore we set Dq last.
724      */
725 
726     env->dregs[regr] = rem;
727     env->dregs[numr] = quot;
728 }
729 
730 void HELPER(divsll)(CPUM68KState *env, int numr, int regr,
731                     int32_t den, int ilen)
732 {
733     int64_t num = deposit64(env->dregs[numr], 32, 32, env->dregs[regr]);
734     int64_t quot;
735     int32_t rem;
736 
737     env->cc_c = 0; /* always cleared, even if overflow/div0 */
738 
739     if (den == 0) {
740         raise_exception_format2(env, EXCP_DIV0, ilen, GETPC());
741     }
742     quot = num / den;
743     rem = num % den;
744 
745     if (quot != (int32_t)quot) {
746         env->cc_v = -1;
747         /*
748          * real 68040 keeps N and unset Z on overflow,
749          * whereas documentation says "undefined"
750          */
751         env->cc_z = 1;
752         return;
753     }
754     env->cc_z = quot;
755     env->cc_n = quot;
756     env->cc_v = 0;
757 
758     /*
759      * If Dq and Dr are the same, the quotient is returned.
760      * therefore we set Dq last.
761      */
762 
763     env->dregs[regr] = rem;
764     env->dregs[numr] = quot;
765 }
766 
767 /* We're executing in a serial context -- no need to be atomic.  */
768 void HELPER(cas2w)(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2)
769 {
770     uint32_t Dc1 = extract32(regs, 9, 3);
771     uint32_t Dc2 = extract32(regs, 6, 3);
772     uint32_t Du1 = extract32(regs, 3, 3);
773     uint32_t Du2 = extract32(regs, 0, 3);
774     int16_t c1 = env->dregs[Dc1];
775     int16_t c2 = env->dregs[Dc2];
776     int16_t u1 = env->dregs[Du1];
777     int16_t u2 = env->dregs[Du2];
778     int16_t l1, l2;
779     uintptr_t ra = GETPC();
780 
781     l1 = cpu_lduw_data_ra(env, a1, ra);
782     l2 = cpu_lduw_data_ra(env, a2, ra);
783     if (l1 == c1 && l2 == c2) {
784         cpu_stw_data_ra(env, a1, u1, ra);
785         cpu_stw_data_ra(env, a2, u2, ra);
786     }
787 
788     if (c1 != l1) {
789         env->cc_n = l1;
790         env->cc_v = c1;
791     } else {
792         env->cc_n = l2;
793         env->cc_v = c2;
794     }
795     env->cc_op = CC_OP_CMPW;
796     env->dregs[Dc1] = deposit32(env->dregs[Dc1], 0, 16, l1);
797     env->dregs[Dc2] = deposit32(env->dregs[Dc2], 0, 16, l2);
798 }
799 
800 static void do_cas2l(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2,
801                      bool parallel)
802 {
803     uint32_t Dc1 = extract32(regs, 9, 3);
804     uint32_t Dc2 = extract32(regs, 6, 3);
805     uint32_t Du1 = extract32(regs, 3, 3);
806     uint32_t Du2 = extract32(regs, 0, 3);
807     uint32_t c1 = env->dregs[Dc1];
808     uint32_t c2 = env->dregs[Dc2];
809     uint32_t u1 = env->dregs[Du1];
810     uint32_t u2 = env->dregs[Du2];
811     uint32_t l1, l2;
812     uintptr_t ra = GETPC();
813 #if defined(CONFIG_ATOMIC64)
814     int mmu_idx = cpu_mmu_index(env_cpu(env), 0);
815     MemOpIdx oi = make_memop_idx(MO_BEUQ, mmu_idx);
816 #endif
817 
818     if (parallel) {
819         /* We're executing in a parallel context -- must be atomic.  */
820 #ifdef CONFIG_ATOMIC64
821         uint64_t c, u, l;
822         if ((a1 & 7) == 0 && a2 == a1 + 4) {
823             c = deposit64(c2, 32, 32, c1);
824             u = deposit64(u2, 32, 32, u1);
825             l = cpu_atomic_cmpxchgq_be_mmu(env, a1, c, u, oi, ra);
826             l1 = l >> 32;
827             l2 = l;
828         } else if ((a2 & 7) == 0 && a1 == a2 + 4) {
829             c = deposit64(c1, 32, 32, c2);
830             u = deposit64(u1, 32, 32, u2);
831             l = cpu_atomic_cmpxchgq_be_mmu(env, a2, c, u, oi, ra);
832             l2 = l >> 32;
833             l1 = l;
834         } else
835 #endif
836         {
837             /* Tell the main loop we need to serialize this insn.  */
838             cpu_loop_exit_atomic(env_cpu(env), ra);
839         }
840     } else {
841         /* We're executing in a serial context -- no need to be atomic.  */
842         l1 = cpu_ldl_data_ra(env, a1, ra);
843         l2 = cpu_ldl_data_ra(env, a2, ra);
844         if (l1 == c1 && l2 == c2) {
845             cpu_stl_data_ra(env, a1, u1, ra);
846             cpu_stl_data_ra(env, a2, u2, ra);
847         }
848     }
849 
850     if (c1 != l1) {
851         env->cc_n = l1;
852         env->cc_v = c1;
853     } else {
854         env->cc_n = l2;
855         env->cc_v = c2;
856     }
857     env->cc_op = CC_OP_CMPL;
858     env->dregs[Dc1] = l1;
859     env->dregs[Dc2] = l2;
860 }
861 
862 void HELPER(cas2l)(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2)
863 {
864     do_cas2l(env, regs, a1, a2, false);
865 }
866 
867 void HELPER(cas2l_parallel)(CPUM68KState *env, uint32_t regs, uint32_t a1,
868                             uint32_t a2)
869 {
870     do_cas2l(env, regs, a1, a2, true);
871 }
872 
873 struct bf_data {
874     uint32_t addr;
875     uint32_t bofs;
876     uint32_t blen;
877     uint32_t len;
878 };
879 
880 static struct bf_data bf_prep(uint32_t addr, int32_t ofs, uint32_t len)
881 {
882     int bofs, blen;
883 
884     /* Bound length; map 0 to 32.  */
885     len = ((len - 1) & 31) + 1;
886 
887     /* Note that ofs is signed.  */
888     addr += ofs / 8;
889     bofs = ofs % 8;
890     if (bofs < 0) {
891         bofs += 8;
892         addr -= 1;
893     }
894 
895     /*
896      * Compute the number of bytes required (minus one) to
897      * satisfy the bitfield.
898      */
899     blen = (bofs + len - 1) / 8;
900 
901     /*
902      * Canonicalize the bit offset for data loaded into a 64-bit big-endian
903      * word.  For the cases where BLEN is not a power of 2, adjust ADDR so
904      * that we can use the next power of two sized load without crossing a
905      * page boundary, unless the field itself crosses the boundary.
906      */
907     switch (blen) {
908     case 0:
909         bofs += 56;
910         break;
911     case 1:
912         bofs += 48;
913         break;
914     case 2:
915         if (addr & 1) {
916             bofs += 8;
917             addr -= 1;
918         }
919         /* fallthru */
920     case 3:
921         bofs += 32;
922         break;
923     case 4:
924         if (addr & 3) {
925             bofs += 8 * (addr & 3);
926             addr &= -4;
927         }
928         break;
929     default:
930         g_assert_not_reached();
931     }
932 
933     return (struct bf_data){
934         .addr = addr,
935         .bofs = bofs,
936         .blen = blen,
937         .len = len,
938     };
939 }
940 
941 static uint64_t bf_load(CPUM68KState *env, uint32_t addr, int blen,
942                         uintptr_t ra)
943 {
944     switch (blen) {
945     case 0:
946         return cpu_ldub_data_ra(env, addr, ra);
947     case 1:
948         return cpu_lduw_data_ra(env, addr, ra);
949     case 2:
950     case 3:
951         return cpu_ldl_data_ra(env, addr, ra);
952     case 4:
953         return cpu_ldq_data_ra(env, addr, ra);
954     default:
955         g_assert_not_reached();
956     }
957 }
958 
959 static void bf_store(CPUM68KState *env, uint32_t addr, int blen,
960                      uint64_t data, uintptr_t ra)
961 {
962     switch (blen) {
963     case 0:
964         cpu_stb_data_ra(env, addr, data, ra);
965         break;
966     case 1:
967         cpu_stw_data_ra(env, addr, data, ra);
968         break;
969     case 2:
970     case 3:
971         cpu_stl_data_ra(env, addr, data, ra);
972         break;
973     case 4:
974         cpu_stq_data_ra(env, addr, data, ra);
975         break;
976     default:
977         g_assert_not_reached();
978     }
979 }
980 
981 uint32_t HELPER(bfexts_mem)(CPUM68KState *env, uint32_t addr,
982                             int32_t ofs, uint32_t len)
983 {
984     uintptr_t ra = GETPC();
985     struct bf_data d = bf_prep(addr, ofs, len);
986     uint64_t data = bf_load(env, d.addr, d.blen, ra);
987 
988     return (int64_t)(data << d.bofs) >> (64 - d.len);
989 }
990 
991 uint64_t HELPER(bfextu_mem)(CPUM68KState *env, uint32_t addr,
992                             int32_t ofs, uint32_t len)
993 {
994     uintptr_t ra = GETPC();
995     struct bf_data d = bf_prep(addr, ofs, len);
996     uint64_t data = bf_load(env, d.addr, d.blen, ra);
997 
998     /*
999      * Put CC_N at the top of the high word; put the zero-extended value
1000      * at the bottom of the low word.
1001      */
1002     data <<= d.bofs;
1003     data >>= 64 - d.len;
1004     data |= data << (64 - d.len);
1005 
1006     return data;
1007 }
1008 
1009 uint32_t HELPER(bfins_mem)(CPUM68KState *env, uint32_t addr, uint32_t val,
1010                            int32_t ofs, uint32_t len)
1011 {
1012     uintptr_t ra = GETPC();
1013     struct bf_data d = bf_prep(addr, ofs, len);
1014     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1015     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1016 
1017     data = (data & ~mask) | (((uint64_t)val << (64 - d.len)) >> d.bofs);
1018 
1019     bf_store(env, d.addr, d.blen, data, ra);
1020 
1021     /* The field at the top of the word is also CC_N for CC_OP_LOGIC.  */
1022     return val << (32 - d.len);
1023 }
1024 
1025 uint32_t HELPER(bfchg_mem)(CPUM68KState *env, uint32_t addr,
1026                            int32_t ofs, uint32_t len)
1027 {
1028     uintptr_t ra = GETPC();
1029     struct bf_data d = bf_prep(addr, ofs, len);
1030     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1031     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1032 
1033     bf_store(env, d.addr, d.blen, data ^ mask, ra);
1034 
1035     return ((data & mask) << d.bofs) >> 32;
1036 }
1037 
1038 uint32_t HELPER(bfclr_mem)(CPUM68KState *env, uint32_t addr,
1039                            int32_t ofs, uint32_t len)
1040 {
1041     uintptr_t ra = GETPC();
1042     struct bf_data d = bf_prep(addr, ofs, len);
1043     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1044     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1045 
1046     bf_store(env, d.addr, d.blen, data & ~mask, ra);
1047 
1048     return ((data & mask) << d.bofs) >> 32;
1049 }
1050 
1051 uint32_t HELPER(bfset_mem)(CPUM68KState *env, uint32_t addr,
1052                            int32_t ofs, uint32_t len)
1053 {
1054     uintptr_t ra = GETPC();
1055     struct bf_data d = bf_prep(addr, ofs, len);
1056     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1057     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1058 
1059     bf_store(env, d.addr, d.blen, data | mask, ra);
1060 
1061     return ((data & mask) << d.bofs) >> 32;
1062 }
1063 
1064 uint32_t HELPER(bfffo_reg)(uint32_t n, uint32_t ofs, uint32_t len)
1065 {
1066     return (n ? clz32(n) : len) + ofs;
1067 }
1068 
1069 uint64_t HELPER(bfffo_mem)(CPUM68KState *env, uint32_t addr,
1070                            int32_t ofs, uint32_t len)
1071 {
1072     uintptr_t ra = GETPC();
1073     struct bf_data d = bf_prep(addr, ofs, len);
1074     uint64_t data = bf_load(env, d.addr, d.blen, ra);
1075     uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
1076     uint64_t n = (data & mask) << d.bofs;
1077     uint32_t ffo = helper_bfffo_reg(n >> 32, ofs, d.len);
1078 
1079     /*
1080      * Return FFO in the low word and N in the high word.
1081      * Note that because of MASK and the shift, the low word
1082      * is already zero.
1083      */
1084     return n | ffo;
1085 }
1086 
1087 void HELPER(chk)(CPUM68KState *env, int32_t val, int32_t ub)
1088 {
1089     /*
1090      * From the specs:
1091      *   X: Not affected, C,V,Z: Undefined,
1092      *   N: Set if val < 0; cleared if val > ub, undefined otherwise
1093      * We implement here values found from a real MC68040:
1094      *   X,V,Z: Not affected
1095      *   N: Set if val < 0; cleared if val >= 0
1096      *   C: if 0 <= ub: set if val < 0 or val > ub, cleared otherwise
1097      *      if 0 > ub: set if val > ub and val < 0, cleared otherwise
1098      */
1099     env->cc_n = val;
1100     env->cc_c = 0 <= ub ? val < 0 || val > ub : val > ub && val < 0;
1101 
1102     if (val < 0 || val > ub) {
1103         raise_exception_format2(env, EXCP_CHK, 2, GETPC());
1104     }
1105 }
1106 
1107 void HELPER(chk2)(CPUM68KState *env, int32_t val, int32_t lb, int32_t ub)
1108 {
1109     /*
1110      * From the specs:
1111      *   X: Not affected, N,V: Undefined,
1112      *   Z: Set if val is equal to lb or ub
1113      *   C: Set if val < lb or val > ub, cleared otherwise
1114      * We implement here values found from a real MC68040:
1115      *   X,N,V: Not affected
1116      *   Z: Set if val is equal to lb or ub
1117      *   C: if lb <= ub: set if val < lb or val > ub, cleared otherwise
1118      *      if lb > ub: set if val > ub and val < lb, cleared otherwise
1119      */
1120     env->cc_z = val != lb && val != ub;
1121     env->cc_c = lb <= ub ? val < lb || val > ub : val > ub && val < lb;
1122 
1123     if (env->cc_c) {
1124         raise_exception_format2(env, EXCP_CHK, 4, GETPC());
1125     }
1126 }
1127