xref: /openbmc/qemu/target/microblaze/op_helper.c (revision 77d361b1) 
1 /*
2  *  Microblaze helper routines.
3  *
4  *  Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>.
5  *  Copyright (c) 2009-2012 PetaLogix Qld Pty Ltd.
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "cpu.h"
23 #include "exec/helper-proto.h"
24 #include "qemu/host-utils.h"
25 #include "exec/exec-all.h"
26 #include "exec/cpu_ldst.h"
27 #include "fpu/softfloat.h"
28 
29 #define D(x)
30 
31 #if !defined(CONFIG_USER_ONLY)
32 
33 /* Try to fill the TLB and return an exception if error. If retaddr is
34  * NULL, it means that the function was called in C code (i.e. not
35  * from generated code or from helper.c)
36  */
37 void tlb_fill(CPUState *cs, target_ulong addr, int size,
38               MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
39 {
40     int ret;
41 
42     ret = mb_cpu_handle_mmu_fault(cs, addr, size, access_type, mmu_idx);
43     if (unlikely(ret)) {
44         /* now we have a real cpu fault */
45         cpu_loop_exit_restore(cs, retaddr);
46     }
47 }
48 #endif
49 
50 void helper_put(uint32_t id, uint32_t ctrl, uint32_t data)
51 {
52     int test = ctrl & STREAM_TEST;
53     int atomic = ctrl & STREAM_ATOMIC;
54     int control = ctrl & STREAM_CONTROL;
55     int nonblock = ctrl & STREAM_NONBLOCK;
56     int exception = ctrl & STREAM_EXCEPTION;
57 
58     qemu_log_mask(LOG_UNIMP, "Unhandled stream put to stream-id=%d data=%x %s%s%s%s%s\n",
59              id, data,
60              test ? "t" : "",
61              nonblock ? "n" : "",
62              exception ? "e" : "",
63              control ? "c" : "",
64              atomic ? "a" : "");
65 }
66 
67 uint32_t helper_get(uint32_t id, uint32_t ctrl)
68 {
69     int test = ctrl & STREAM_TEST;
70     int atomic = ctrl & STREAM_ATOMIC;
71     int control = ctrl & STREAM_CONTROL;
72     int nonblock = ctrl & STREAM_NONBLOCK;
73     int exception = ctrl & STREAM_EXCEPTION;
74 
75     qemu_log_mask(LOG_UNIMP, "Unhandled stream get from stream-id=%d %s%s%s%s%s\n",
76              id,
77              test ? "t" : "",
78              nonblock ? "n" : "",
79              exception ? "e" : "",
80              control ? "c" : "",
81              atomic ? "a" : "");
82     return 0xdead0000 | id;
83 }
84 
85 void helper_raise_exception(CPUMBState *env, uint32_t index)
86 {
87     CPUState *cs = CPU(mb_env_get_cpu(env));
88 
89     cs->exception_index = index;
90     cpu_loop_exit(cs);
91 }
92 
93 void helper_debug(CPUMBState *env)
94 {
95     int i;
96 
97     qemu_log("PC=%" PRIx64 "\n", env->sregs[SR_PC]);
98     qemu_log("rmsr=%" PRIx64 " resr=%" PRIx64 " rear=%" PRIx64 " "
99              "debug[%x] imm=%x iflags=%x\n",
100              env->sregs[SR_MSR], env->sregs[SR_ESR], env->sregs[SR_EAR],
101              env->debug, env->imm, env->iflags);
102     qemu_log("btaken=%d btarget=%" PRIx64 " mode=%s(saved=%s) eip=%d ie=%d\n",
103              env->btaken, env->btarget,
104              (env->sregs[SR_MSR] & MSR_UM) ? "user" : "kernel",
105              (env->sregs[SR_MSR] & MSR_UMS) ? "user" : "kernel",
106              (bool)(env->sregs[SR_MSR] & MSR_EIP),
107              (bool)(env->sregs[SR_MSR] & MSR_IE));
108     for (i = 0; i < 32; i++) {
109         qemu_log("r%2.2d=%8.8x ", i, env->regs[i]);
110         if ((i + 1) % 4 == 0)
111             qemu_log("\n");
112     }
113     qemu_log("\n\n");
114 }
115 
116 static inline uint32_t compute_carry(uint32_t a, uint32_t b, uint32_t cin)
117 {
118     uint32_t cout = 0;
119 
120     if ((b == ~0) && cin)
121         cout = 1;
122     else if ((~0 - a) < (b + cin))
123         cout = 1;
124     return cout;
125 }
126 
127 uint32_t helper_cmp(uint32_t a, uint32_t b)
128 {
129     uint32_t t;
130 
131     t = b + ~a + 1;
132     if ((b & 0x80000000) ^ (a & 0x80000000))
133         t = (t & 0x7fffffff) | (b & 0x80000000);
134     return t;
135 }
136 
137 uint32_t helper_cmpu(uint32_t a, uint32_t b)
138 {
139     uint32_t t;
140 
141     t = b + ~a + 1;
142     if ((b & 0x80000000) ^ (a & 0x80000000))
143         t = (t & 0x7fffffff) | (a & 0x80000000);
144     return t;
145 }
146 
147 uint32_t helper_carry(uint32_t a, uint32_t b, uint32_t cf)
148 {
149     return compute_carry(a, b, cf);
150 }
151 
152 static inline int div_prepare(CPUMBState *env, uint32_t a, uint32_t b)
153 {
154     if (b == 0) {
155         env->sregs[SR_MSR] |= MSR_DZ;
156 
157         if ((env->sregs[SR_MSR] & MSR_EE)
158             && !(env->pvr.regs[2] & PVR2_DIV_ZERO_EXC_MASK)) {
159             env->sregs[SR_ESR] = ESR_EC_DIVZERO;
160             helper_raise_exception(env, EXCP_HW_EXCP);
161         }
162         return 0;
163     }
164     env->sregs[SR_MSR] &= ~MSR_DZ;
165     return 1;
166 }
167 
168 uint32_t helper_divs(CPUMBState *env, uint32_t a, uint32_t b)
169 {
170     if (!div_prepare(env, a, b)) {
171         return 0;
172     }
173     return (int32_t)a / (int32_t)b;
174 }
175 
176 uint32_t helper_divu(CPUMBState *env, uint32_t a, uint32_t b)
177 {
178     if (!div_prepare(env, a, b)) {
179         return 0;
180     }
181     return a / b;
182 }
183 
184 /* raise FPU exception.  */
185 static void raise_fpu_exception(CPUMBState *env)
186 {
187     env->sregs[SR_ESR] = ESR_EC_FPU;
188     helper_raise_exception(env, EXCP_HW_EXCP);
189 }
190 
191 static void update_fpu_flags(CPUMBState *env, int flags)
192 {
193     int raise = 0;
194 
195     if (flags & float_flag_invalid) {
196         env->sregs[SR_FSR] |= FSR_IO;
197         raise = 1;
198     }
199     if (flags & float_flag_divbyzero) {
200         env->sregs[SR_FSR] |= FSR_DZ;
201         raise = 1;
202     }
203     if (flags & float_flag_overflow) {
204         env->sregs[SR_FSR] |= FSR_OF;
205         raise = 1;
206     }
207     if (flags & float_flag_underflow) {
208         env->sregs[SR_FSR] |= FSR_UF;
209         raise = 1;
210     }
211     if (raise
212         && (env->pvr.regs[2] & PVR2_FPU_EXC_MASK)
213         && (env->sregs[SR_MSR] & MSR_EE)) {
214         raise_fpu_exception(env);
215     }
216 }
217 
218 uint32_t helper_fadd(CPUMBState *env, uint32_t a, uint32_t b)
219 {
220     CPU_FloatU fd, fa, fb;
221     int flags;
222 
223     set_float_exception_flags(0, &env->fp_status);
224     fa.l = a;
225     fb.l = b;
226     fd.f = float32_add(fa.f, fb.f, &env->fp_status);
227 
228     flags = get_float_exception_flags(&env->fp_status);
229     update_fpu_flags(env, flags);
230     return fd.l;
231 }
232 
233 uint32_t helper_frsub(CPUMBState *env, uint32_t a, uint32_t b)
234 {
235     CPU_FloatU fd, fa, fb;
236     int flags;
237 
238     set_float_exception_flags(0, &env->fp_status);
239     fa.l = a;
240     fb.l = b;
241     fd.f = float32_sub(fb.f, fa.f, &env->fp_status);
242     flags = get_float_exception_flags(&env->fp_status);
243     update_fpu_flags(env, flags);
244     return fd.l;
245 }
246 
247 uint32_t helper_fmul(CPUMBState *env, uint32_t a, uint32_t b)
248 {
249     CPU_FloatU fd, fa, fb;
250     int flags;
251 
252     set_float_exception_flags(0, &env->fp_status);
253     fa.l = a;
254     fb.l = b;
255     fd.f = float32_mul(fa.f, fb.f, &env->fp_status);
256     flags = get_float_exception_flags(&env->fp_status);
257     update_fpu_flags(env, flags);
258 
259     return fd.l;
260 }
261 
262 uint32_t helper_fdiv(CPUMBState *env, uint32_t a, uint32_t b)
263 {
264     CPU_FloatU fd, fa, fb;
265     int flags;
266 
267     set_float_exception_flags(0, &env->fp_status);
268     fa.l = a;
269     fb.l = b;
270     fd.f = float32_div(fb.f, fa.f, &env->fp_status);
271     flags = get_float_exception_flags(&env->fp_status);
272     update_fpu_flags(env, flags);
273 
274     return fd.l;
275 }
276 
277 uint32_t helper_fcmp_un(CPUMBState *env, uint32_t a, uint32_t b)
278 {
279     CPU_FloatU fa, fb;
280     uint32_t r = 0;
281 
282     fa.l = a;
283     fb.l = b;
284 
285     if (float32_is_signaling_nan(fa.f, &env->fp_status) ||
286         float32_is_signaling_nan(fb.f, &env->fp_status)) {
287         update_fpu_flags(env, float_flag_invalid);
288         r = 1;
289     }
290 
291     if (float32_is_quiet_nan(fa.f, &env->fp_status) ||
292         float32_is_quiet_nan(fb.f, &env->fp_status)) {
293         r = 1;
294     }
295 
296     return r;
297 }
298 
299 uint32_t helper_fcmp_lt(CPUMBState *env, uint32_t a, uint32_t b)
300 {
301     CPU_FloatU fa, fb;
302     int r;
303     int flags;
304 
305     set_float_exception_flags(0, &env->fp_status);
306     fa.l = a;
307     fb.l = b;
308     r = float32_lt(fb.f, fa.f, &env->fp_status);
309     flags = get_float_exception_flags(&env->fp_status);
310     update_fpu_flags(env, flags & float_flag_invalid);
311 
312     return r;
313 }
314 
315 uint32_t helper_fcmp_eq(CPUMBState *env, uint32_t a, uint32_t b)
316 {
317     CPU_FloatU fa, fb;
318     int flags;
319     int r;
320 
321     set_float_exception_flags(0, &env->fp_status);
322     fa.l = a;
323     fb.l = b;
324     r = float32_eq_quiet(fa.f, fb.f, &env->fp_status);
325     flags = get_float_exception_flags(&env->fp_status);
326     update_fpu_flags(env, flags & float_flag_invalid);
327 
328     return r;
329 }
330 
331 uint32_t helper_fcmp_le(CPUMBState *env, uint32_t a, uint32_t b)
332 {
333     CPU_FloatU fa, fb;
334     int flags;
335     int r;
336 
337     fa.l = a;
338     fb.l = b;
339     set_float_exception_flags(0, &env->fp_status);
340     r = float32_le(fa.f, fb.f, &env->fp_status);
341     flags = get_float_exception_flags(&env->fp_status);
342     update_fpu_flags(env, flags & float_flag_invalid);
343 
344 
345     return r;
346 }
347 
348 uint32_t helper_fcmp_gt(CPUMBState *env, uint32_t a, uint32_t b)
349 {
350     CPU_FloatU fa, fb;
351     int flags, r;
352 
353     fa.l = a;
354     fb.l = b;
355     set_float_exception_flags(0, &env->fp_status);
356     r = float32_lt(fa.f, fb.f, &env->fp_status);
357     flags = get_float_exception_flags(&env->fp_status);
358     update_fpu_flags(env, flags & float_flag_invalid);
359     return r;
360 }
361 
362 uint32_t helper_fcmp_ne(CPUMBState *env, uint32_t a, uint32_t b)
363 {
364     CPU_FloatU fa, fb;
365     int flags, r;
366 
367     fa.l = a;
368     fb.l = b;
369     set_float_exception_flags(0, &env->fp_status);
370     r = !float32_eq_quiet(fa.f, fb.f, &env->fp_status);
371     flags = get_float_exception_flags(&env->fp_status);
372     update_fpu_flags(env, flags & float_flag_invalid);
373 
374     return r;
375 }
376 
377 uint32_t helper_fcmp_ge(CPUMBState *env, uint32_t a, uint32_t b)
378 {
379     CPU_FloatU fa, fb;
380     int flags, r;
381 
382     fa.l = a;
383     fb.l = b;
384     set_float_exception_flags(0, &env->fp_status);
385     r = !float32_lt(fa.f, fb.f, &env->fp_status);
386     flags = get_float_exception_flags(&env->fp_status);
387     update_fpu_flags(env, flags & float_flag_invalid);
388 
389     return r;
390 }
391 
392 uint32_t helper_flt(CPUMBState *env, uint32_t a)
393 {
394     CPU_FloatU fd, fa;
395 
396     fa.l = a;
397     fd.f = int32_to_float32(fa.l, &env->fp_status);
398     return fd.l;
399 }
400 
401 uint32_t helper_fint(CPUMBState *env, uint32_t a)
402 {
403     CPU_FloatU fa;
404     uint32_t r;
405     int flags;
406 
407     set_float_exception_flags(0, &env->fp_status);
408     fa.l = a;
409     r = float32_to_int32(fa.f, &env->fp_status);
410     flags = get_float_exception_flags(&env->fp_status);
411     update_fpu_flags(env, flags);
412 
413     return r;
414 }
415 
416 uint32_t helper_fsqrt(CPUMBState *env, uint32_t a)
417 {
418     CPU_FloatU fd, fa;
419     int flags;
420 
421     set_float_exception_flags(0, &env->fp_status);
422     fa.l = a;
423     fd.l = float32_sqrt(fa.f, &env->fp_status);
424     flags = get_float_exception_flags(&env->fp_status);
425     update_fpu_flags(env, flags);
426 
427     return fd.l;
428 }
429 
430 uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
431 {
432     unsigned int i;
433     uint32_t mask = 0xff000000;
434 
435     for (i = 0; i < 4; i++) {
436         if ((a & mask) == (b & mask))
437             return i + 1;
438         mask >>= 8;
439     }
440     return 0;
441 }
442 
443 void helper_memalign(CPUMBState *env, target_ulong addr,
444                      uint32_t dr, uint32_t wr,
445                      uint32_t mask)
446 {
447     if (addr & mask) {
448             qemu_log_mask(CPU_LOG_INT,
449                           "unaligned access addr=" TARGET_FMT_lx
450                           " mask=%x, wr=%d dr=r%d\n",
451                           addr, mask, wr, dr);
452             env->sregs[SR_EAR] = addr;
453             env->sregs[SR_ESR] = ESR_EC_UNALIGNED_DATA | (wr << 10) \
454                                  | (dr & 31) << 5;
455             if (mask == 3) {
456                 env->sregs[SR_ESR] |= 1 << 11;
457             }
458             if (!(env->sregs[SR_MSR] & MSR_EE)) {
459                 return;
460             }
461             helper_raise_exception(env, EXCP_HW_EXCP);
462     }
463 }
464 
465 void helper_stackprot(CPUMBState *env, target_ulong addr)
466 {
467     if (addr < env->slr || addr > env->shr) {
468         qemu_log_mask(CPU_LOG_INT, "Stack protector violation at "
469                       TARGET_FMT_lx " %x %x\n",
470                       addr, env->slr, env->shr);
471         env->sregs[SR_EAR] = addr;
472         env->sregs[SR_ESR] = ESR_EC_STACKPROT;
473         helper_raise_exception(env, EXCP_HW_EXCP);
474     }
475 }
476 
477 #if !defined(CONFIG_USER_ONLY)
478 /* Writes/reads to the MMU's special regs end up here.  */
479 uint32_t helper_mmu_read(CPUMBState *env, uint32_t ext, uint32_t rn)
480 {
481     return mmu_read(env, ext, rn);
482 }
483 
484 void helper_mmu_write(CPUMBState *env, uint32_t ext, uint32_t rn, uint32_t v)
485 {
486     mmu_write(env, ext, rn, v);
487 }
488 
489 void mb_cpu_unassigned_access(CPUState *cs, hwaddr addr,
490                               bool is_write, bool is_exec, int is_asi,
491                               unsigned size)
492 {
493     MicroBlazeCPU *cpu;
494     CPUMBState *env;
495 
496     qemu_log_mask(CPU_LOG_INT, "Unassigned " TARGET_FMT_plx " wr=%d exe=%d\n",
497              addr, is_write ? 1 : 0, is_exec ? 1 : 0);
498     if (cs == NULL) {
499         return;
500     }
501     cpu = MICROBLAZE_CPU(cs);
502     env = &cpu->env;
503     if (!(env->sregs[SR_MSR] & MSR_EE)) {
504         return;
505     }
506 
507     env->sregs[SR_EAR] = addr;
508     if (is_exec) {
509         if ((env->pvr.regs[2] & PVR2_IOPB_BUS_EXC_MASK)) {
510             env->sregs[SR_ESR] = ESR_EC_INSN_BUS;
511             helper_raise_exception(env, EXCP_HW_EXCP);
512         }
513     } else {
514         if ((env->pvr.regs[2] & PVR2_DOPB_BUS_EXC_MASK)) {
515             env->sregs[SR_ESR] = ESR_EC_DATA_BUS;
516             helper_raise_exception(env, EXCP_HW_EXCP);
517         }
518     }
519 }
520 #endif
521