xref: /openbmc/qemu/target/microblaze/op_helper.c (revision 4a09d0bb) 
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 
28 #define D(x)
29 
30 #if !defined(CONFIG_USER_ONLY)
31 
32 /* Try to fill the TLB and return an exception if error. If retaddr is
33  * NULL, it means that the function was called in C code (i.e. not
34  * from generated code or from helper.c)
35  */
36 void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
37               int mmu_idx, uintptr_t retaddr)
38 {
39     int ret;
40 
41     ret = mb_cpu_handle_mmu_fault(cs, addr, access_type, mmu_idx);
42     if (unlikely(ret)) {
43         if (retaddr) {
44             /* now we have a real cpu fault */
45             cpu_restore_state(cs, retaddr);
46         }
47         cpu_loop_exit(cs);
48     }
49 }
50 #endif
51 
52 void helper_put(uint32_t id, uint32_t ctrl, uint32_t data)
53 {
54     int test = ctrl & STREAM_TEST;
55     int atomic = ctrl & STREAM_ATOMIC;
56     int control = ctrl & STREAM_CONTROL;
57     int nonblock = ctrl & STREAM_NONBLOCK;
58     int exception = ctrl & STREAM_EXCEPTION;
59 
60     qemu_log_mask(LOG_UNIMP, "Unhandled stream put to stream-id=%d data=%x %s%s%s%s%s\n",
61              id, data,
62              test ? "t" : "",
63              nonblock ? "n" : "",
64              exception ? "e" : "",
65              control ? "c" : "",
66              atomic ? "a" : "");
67 }
68 
69 uint32_t helper_get(uint32_t id, uint32_t ctrl)
70 {
71     int test = ctrl & STREAM_TEST;
72     int atomic = ctrl & STREAM_ATOMIC;
73     int control = ctrl & STREAM_CONTROL;
74     int nonblock = ctrl & STREAM_NONBLOCK;
75     int exception = ctrl & STREAM_EXCEPTION;
76 
77     qemu_log_mask(LOG_UNIMP, "Unhandled stream get from stream-id=%d %s%s%s%s%s\n",
78              id,
79              test ? "t" : "",
80              nonblock ? "n" : "",
81              exception ? "e" : "",
82              control ? "c" : "",
83              atomic ? "a" : "");
84     return 0xdead0000 | id;
85 }
86 
87 void helper_raise_exception(CPUMBState *env, uint32_t index)
88 {
89     CPUState *cs = CPU(mb_env_get_cpu(env));
90 
91     cs->exception_index = index;
92     cpu_loop_exit(cs);
93 }
94 
95 void helper_debug(CPUMBState *env)
96 {
97     int i;
98 
99     qemu_log("PC=%8.8x\n", env->sregs[SR_PC]);
100     qemu_log("rmsr=%x resr=%x rear=%x debug[%x] imm=%x iflags=%x\n",
101              env->sregs[SR_MSR], env->sregs[SR_ESR], env->sregs[SR_EAR],
102              env->debug, env->imm, env->iflags);
103     qemu_log("btaken=%d btarget=%x mode=%s(saved=%s) eip=%d ie=%d\n",
104              env->btaken, env->btarget,
105              (env->sregs[SR_MSR] & MSR_UM) ? "user" : "kernel",
106              (env->sregs[SR_MSR] & MSR_UMS) ? "user" : "kernel",
107              (env->sregs[SR_MSR] & MSR_EIP),
108              (env->sregs[SR_MSR] & MSR_IE));
109     for (i = 0; i < 32; i++) {
110         qemu_log("r%2.2d=%8.8x ", i, env->regs[i]);
111         if ((i + 1) % 4 == 0)
112             qemu_log("\n");
113     }
114     qemu_log("\n\n");
115 }
116 
117 static inline uint32_t compute_carry(uint32_t a, uint32_t b, uint32_t cin)
118 {
119     uint32_t cout = 0;
120 
121     if ((b == ~0) && cin)
122         cout = 1;
123     else if ((~0 - a) < (b + cin))
124         cout = 1;
125     return cout;
126 }
127 
128 uint32_t helper_cmp(uint32_t a, uint32_t b)
129 {
130     uint32_t t;
131 
132     t = b + ~a + 1;
133     if ((b & 0x80000000) ^ (a & 0x80000000))
134         t = (t & 0x7fffffff) | (b & 0x80000000);
135     return t;
136 }
137 
138 uint32_t helper_cmpu(uint32_t a, uint32_t b)
139 {
140     uint32_t t;
141 
142     t = b + ~a + 1;
143     if ((b & 0x80000000) ^ (a & 0x80000000))
144         t = (t & 0x7fffffff) | (a & 0x80000000);
145     return t;
146 }
147 
148 uint32_t helper_carry(uint32_t a, uint32_t b, uint32_t cf)
149 {
150     return compute_carry(a, b, cf);
151 }
152 
153 static inline int div_prepare(CPUMBState *env, uint32_t a, uint32_t b)
154 {
155     if (b == 0) {
156         env->sregs[SR_MSR] |= MSR_DZ;
157 
158         if ((env->sregs[SR_MSR] & MSR_EE)
159             && !(env->pvr.regs[2] & PVR2_DIV_ZERO_EXC_MASK)) {
160             env->sregs[SR_ESR] = ESR_EC_DIVZERO;
161             helper_raise_exception(env, EXCP_HW_EXCP);
162         }
163         return 0;
164     }
165     env->sregs[SR_MSR] &= ~MSR_DZ;
166     return 1;
167 }
168 
169 uint32_t helper_divs(CPUMBState *env, uint32_t a, uint32_t b)
170 {
171     if (!div_prepare(env, a, b)) {
172         return 0;
173     }
174     return (int32_t)a / (int32_t)b;
175 }
176 
177 uint32_t helper_divu(CPUMBState *env, uint32_t a, uint32_t b)
178 {
179     if (!div_prepare(env, a, b)) {
180         return 0;
181     }
182     return a / b;
183 }
184 
185 /* raise FPU exception.  */
186 static void raise_fpu_exception(CPUMBState *env)
187 {
188     env->sregs[SR_ESR] = ESR_EC_FPU;
189     helper_raise_exception(env, EXCP_HW_EXCP);
190 }
191 
192 static void update_fpu_flags(CPUMBState *env, int flags)
193 {
194     int raise = 0;
195 
196     if (flags & float_flag_invalid) {
197         env->sregs[SR_FSR] |= FSR_IO;
198         raise = 1;
199     }
200     if (flags & float_flag_divbyzero) {
201         env->sregs[SR_FSR] |= FSR_DZ;
202         raise = 1;
203     }
204     if (flags & float_flag_overflow) {
205         env->sregs[SR_FSR] |= FSR_OF;
206         raise = 1;
207     }
208     if (flags & float_flag_underflow) {
209         env->sregs[SR_FSR] |= FSR_UF;
210         raise = 1;
211     }
212     if (raise
213         && (env->pvr.regs[2] & PVR2_FPU_EXC_MASK)
214         && (env->sregs[SR_MSR] & MSR_EE)) {
215         raise_fpu_exception(env);
216     }
217 }
218 
219 uint32_t helper_fadd(CPUMBState *env, uint32_t a, uint32_t b)
220 {
221     CPU_FloatU fd, fa, fb;
222     int flags;
223 
224     set_float_exception_flags(0, &env->fp_status);
225     fa.l = a;
226     fb.l = b;
227     fd.f = float32_add(fa.f, fb.f, &env->fp_status);
228 
229     flags = get_float_exception_flags(&env->fp_status);
230     update_fpu_flags(env, flags);
231     return fd.l;
232 }
233 
234 uint32_t helper_frsub(CPUMBState *env, uint32_t a, uint32_t b)
235 {
236     CPU_FloatU fd, fa, fb;
237     int flags;
238 
239     set_float_exception_flags(0, &env->fp_status);
240     fa.l = a;
241     fb.l = b;
242     fd.f = float32_sub(fb.f, fa.f, &env->fp_status);
243     flags = get_float_exception_flags(&env->fp_status);
244     update_fpu_flags(env, flags);
245     return fd.l;
246 }
247 
248 uint32_t helper_fmul(CPUMBState *env, uint32_t a, uint32_t b)
249 {
250     CPU_FloatU fd, fa, fb;
251     int flags;
252 
253     set_float_exception_flags(0, &env->fp_status);
254     fa.l = a;
255     fb.l = b;
256     fd.f = float32_mul(fa.f, fb.f, &env->fp_status);
257     flags = get_float_exception_flags(&env->fp_status);
258     update_fpu_flags(env, flags);
259 
260     return fd.l;
261 }
262 
263 uint32_t helper_fdiv(CPUMBState *env, uint32_t a, uint32_t b)
264 {
265     CPU_FloatU fd, fa, fb;
266     int flags;
267 
268     set_float_exception_flags(0, &env->fp_status);
269     fa.l = a;
270     fb.l = b;
271     fd.f = float32_div(fb.f, fa.f, &env->fp_status);
272     flags = get_float_exception_flags(&env->fp_status);
273     update_fpu_flags(env, flags);
274 
275     return fd.l;
276 }
277 
278 uint32_t helper_fcmp_un(CPUMBState *env, uint32_t a, uint32_t b)
279 {
280     CPU_FloatU fa, fb;
281     uint32_t r = 0;
282 
283     fa.l = a;
284     fb.l = b;
285 
286     if (float32_is_signaling_nan(fa.f, &env->fp_status) ||
287         float32_is_signaling_nan(fb.f, &env->fp_status)) {
288         update_fpu_flags(env, float_flag_invalid);
289         r = 1;
290     }
291 
292     if (float32_is_quiet_nan(fa.f, &env->fp_status) ||
293         float32_is_quiet_nan(fb.f, &env->fp_status)) {
294         r = 1;
295     }
296 
297     return r;
298 }
299 
300 uint32_t helper_fcmp_lt(CPUMBState *env, uint32_t a, uint32_t b)
301 {
302     CPU_FloatU fa, fb;
303     int r;
304     int flags;
305 
306     set_float_exception_flags(0, &env->fp_status);
307     fa.l = a;
308     fb.l = b;
309     r = float32_lt(fb.f, fa.f, &env->fp_status);
310     flags = get_float_exception_flags(&env->fp_status);
311     update_fpu_flags(env, flags & float_flag_invalid);
312 
313     return r;
314 }
315 
316 uint32_t helper_fcmp_eq(CPUMBState *env, uint32_t a, uint32_t b)
317 {
318     CPU_FloatU fa, fb;
319     int flags;
320     int r;
321 
322     set_float_exception_flags(0, &env->fp_status);
323     fa.l = a;
324     fb.l = b;
325     r = float32_eq_quiet(fa.f, fb.f, &env->fp_status);
326     flags = get_float_exception_flags(&env->fp_status);
327     update_fpu_flags(env, flags & float_flag_invalid);
328 
329     return r;
330 }
331 
332 uint32_t helper_fcmp_le(CPUMBState *env, uint32_t a, uint32_t b)
333 {
334     CPU_FloatU fa, fb;
335     int flags;
336     int r;
337 
338     fa.l = a;
339     fb.l = b;
340     set_float_exception_flags(0, &env->fp_status);
341     r = float32_le(fa.f, fb.f, &env->fp_status);
342     flags = get_float_exception_flags(&env->fp_status);
343     update_fpu_flags(env, flags & float_flag_invalid);
344 
345 
346     return r;
347 }
348 
349 uint32_t helper_fcmp_gt(CPUMBState *env, uint32_t a, uint32_t b)
350 {
351     CPU_FloatU fa, fb;
352     int flags, r;
353 
354     fa.l = a;
355     fb.l = b;
356     set_float_exception_flags(0, &env->fp_status);
357     r = float32_lt(fa.f, fb.f, &env->fp_status);
358     flags = get_float_exception_flags(&env->fp_status);
359     update_fpu_flags(env, flags & float_flag_invalid);
360     return r;
361 }
362 
363 uint32_t helper_fcmp_ne(CPUMBState *env, uint32_t a, uint32_t b)
364 {
365     CPU_FloatU fa, fb;
366     int flags, r;
367 
368     fa.l = a;
369     fb.l = b;
370     set_float_exception_flags(0, &env->fp_status);
371     r = !float32_eq_quiet(fa.f, fb.f, &env->fp_status);
372     flags = get_float_exception_flags(&env->fp_status);
373     update_fpu_flags(env, flags & float_flag_invalid);
374 
375     return r;
376 }
377 
378 uint32_t helper_fcmp_ge(CPUMBState *env, uint32_t a, uint32_t b)
379 {
380     CPU_FloatU fa, fb;
381     int flags, r;
382 
383     fa.l = a;
384     fb.l = b;
385     set_float_exception_flags(0, &env->fp_status);
386     r = !float32_lt(fa.f, fb.f, &env->fp_status);
387     flags = get_float_exception_flags(&env->fp_status);
388     update_fpu_flags(env, flags & float_flag_invalid);
389 
390     return r;
391 }
392 
393 uint32_t helper_flt(CPUMBState *env, uint32_t a)
394 {
395     CPU_FloatU fd, fa;
396 
397     fa.l = a;
398     fd.f = int32_to_float32(fa.l, &env->fp_status);
399     return fd.l;
400 }
401 
402 uint32_t helper_fint(CPUMBState *env, uint32_t a)
403 {
404     CPU_FloatU fa;
405     uint32_t r;
406     int flags;
407 
408     set_float_exception_flags(0, &env->fp_status);
409     fa.l = a;
410     r = float32_to_int32(fa.f, &env->fp_status);
411     flags = get_float_exception_flags(&env->fp_status);
412     update_fpu_flags(env, flags);
413 
414     return r;
415 }
416 
417 uint32_t helper_fsqrt(CPUMBState *env, uint32_t a)
418 {
419     CPU_FloatU fd, fa;
420     int flags;
421 
422     set_float_exception_flags(0, &env->fp_status);
423     fa.l = a;
424     fd.l = float32_sqrt(fa.f, &env->fp_status);
425     flags = get_float_exception_flags(&env->fp_status);
426     update_fpu_flags(env, flags);
427 
428     return fd.l;
429 }
430 
431 uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
432 {
433     unsigned int i;
434     uint32_t mask = 0xff000000;
435 
436     for (i = 0; i < 4; i++) {
437         if ((a & mask) == (b & mask))
438             return i + 1;
439         mask >>= 8;
440     }
441     return 0;
442 }
443 
444 void helper_memalign(CPUMBState *env, uint32_t addr, 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=%x mask=%x, wr=%d dr=r%d\n",
450                           addr, mask, wr, dr);
451             env->sregs[SR_EAR] = addr;
452             env->sregs[SR_ESR] = ESR_EC_UNALIGNED_DATA | (wr << 10) \
453                                  | (dr & 31) << 5;
454             if (mask == 3) {
455                 env->sregs[SR_ESR] |= 1 << 11;
456             }
457             if (!(env->sregs[SR_MSR] & MSR_EE)) {
458                 return;
459             }
460             helper_raise_exception(env, EXCP_HW_EXCP);
461     }
462 }
463 
464 void helper_stackprot(CPUMBState *env, uint32_t addr)
465 {
466     if (addr < env->slr || addr > env->shr) {
467         qemu_log_mask(CPU_LOG_INT, "Stack protector violation at %x %x %x\n",
468                       addr, env->slr, env->shr);
469         env->sregs[SR_EAR] = addr;
470         env->sregs[SR_ESR] = ESR_EC_STACKPROT;
471         helper_raise_exception(env, EXCP_HW_EXCP);
472     }
473 }
474 
475 #if !defined(CONFIG_USER_ONLY)
476 /* Writes/reads to the MMU's special regs end up here.  */
477 uint32_t helper_mmu_read(CPUMBState *env, uint32_t rn)
478 {
479     return mmu_read(env, rn);
480 }
481 
482 void helper_mmu_write(CPUMBState *env, uint32_t rn, uint32_t v)
483 {
484     mmu_write(env, rn, v);
485 }
486 
487 void mb_cpu_unassigned_access(CPUState *cs, hwaddr addr,
488                               bool is_write, bool is_exec, int is_asi,
489                               unsigned size)
490 {
491     MicroBlazeCPU *cpu;
492     CPUMBState *env;
493 
494     qemu_log_mask(CPU_LOG_INT, "Unassigned " TARGET_FMT_plx " wr=%d exe=%d\n",
495              addr, is_write ? 1 : 0, is_exec ? 1 : 0);
496     if (cs == NULL) {
497         return;
498     }
499     cpu = MICROBLAZE_CPU(cs);
500     env = &cpu->env;
501     if (!(env->sregs[SR_MSR] & MSR_EE)) {
502         return;
503     }
504 
505     env->sregs[SR_EAR] = addr;
506     if (is_exec) {
507         if ((env->pvr.regs[2] & PVR2_IOPB_BUS_EXC_MASK)) {
508             env->sregs[SR_ESR] = ESR_EC_INSN_BUS;
509             helper_raise_exception(env, EXCP_HW_EXCP);
510         }
511     } else {
512         if ((env->pvr.regs[2] & PVR2_DOPB_BUS_EXC_MASK)) {
513             env->sregs[SR_ESR] = ESR_EC_DATA_BUS;
514             helper_raise_exception(env, EXCP_HW_EXCP);
515         }
516     }
517 }
518 #endif
519