KVM: ppc: use macros instead of hardcoded literals for instruction decoding
[linux-3.10.git] / arch / powerpc / kvm / emulate.c
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License, version 2, as
4  * published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9  * GNU General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with this program; if not, write to the Free Software
13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
14  *
15  * Copyright IBM Corp. 2007
16  *
17  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
18  */
19
20 #include <linux/jiffies.h>
21 #include <linux/timer.h>
22 #include <linux/types.h>
23 #include <linux/string.h>
24 #include <linux/kvm_host.h>
25
26 #include <asm/reg.h>
27 #include <asm/time.h>
28 #include <asm/byteorder.h>
29 #include <asm/kvm_ppc.h>
30 #include <asm/disassemble.h>
31 #include "timing.h"
32
33 #define OP_TRAP 3
34
35 #define OP_31_XOP_LWZX      23
36 #define OP_31_XOP_LBZX      87
37 #define OP_31_XOP_STWX      151
38 #define OP_31_XOP_STBX      215
39 #define OP_31_XOP_STBUX     247
40 #define OP_31_XOP_LHZX      279
41 #define OP_31_XOP_LHZUX     311
42 #define OP_31_XOP_MFSPR     339
43 #define OP_31_XOP_STHX      407
44 #define OP_31_XOP_STHUX     439
45 #define OP_31_XOP_MTSPR     467
46 #define OP_31_XOP_DCBI      470
47 #define OP_31_XOP_LWBRX     534
48 #define OP_31_XOP_TLBSYNC   566
49 #define OP_31_XOP_STWBRX    662
50 #define OP_31_XOP_LHBRX     790
51 #define OP_31_XOP_STHBRX    918
52
53 #define OP_LWZ  32
54 #define OP_LWZU 33
55 #define OP_LBZ  34
56 #define OP_LBZU 35
57 #define OP_STW  36
58 #define OP_STWU 37
59 #define OP_STB  38
60 #define OP_STBU 39
61 #define OP_LHZ  40
62 #define OP_LHZU 41
63 #define OP_STH  44
64 #define OP_STHU 45
65
66 void kvmppc_emulate_dec(struct kvm_vcpu *vcpu)
67 {
68         if (vcpu->arch.tcr & TCR_DIE) {
69                 /* The decrementer ticks at the same rate as the timebase, so
70                  * that's how we convert the guest DEC value to the number of
71                  * host ticks. */
72                 unsigned long nr_jiffies;
73
74                 nr_jiffies = vcpu->arch.dec / tb_ticks_per_jiffy;
75                 mod_timer(&vcpu->arch.dec_timer,
76                           get_jiffies_64() + nr_jiffies);
77         } else {
78                 del_timer(&vcpu->arch.dec_timer);
79         }
80 }
81
82 /* XXX to do:
83  * lhax
84  * lhaux
85  * lswx
86  * lswi
87  * stswx
88  * stswi
89  * lha
90  * lhau
91  * lmw
92  * stmw
93  *
94  * XXX is_bigendian should depend on MMU mapping or MSR[LE]
95  */
96 /* XXX Should probably auto-generate instruction decoding for a particular core
97  * from opcode tables in the future. */
98 int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
99 {
100         u32 inst = vcpu->arch.last_inst;
101         u32 ea;
102         int ra;
103         int rb;
104         int rs;
105         int rt;
106         int sprn;
107         enum emulation_result emulated = EMULATE_DONE;
108         int advance = 1;
109
110         /* this default type might be overwritten by subcategories */
111         kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS);
112
113         switch (get_op(inst)) {
114         case OP_TRAP:
115                 vcpu->arch.esr |= ESR_PTR;
116                 kvmppc_core_queue_program(vcpu);
117                 advance = 0;
118                 break;
119
120         case 31:
121                 switch (get_xop(inst)) {
122
123                 case OP_31_XOP_LWZX:
124                         rt = get_rt(inst);
125                         emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
126                         break;
127
128                 case OP_31_XOP_LBZX:
129                         rt = get_rt(inst);
130                         emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
131                         break;
132
133                 case OP_31_XOP_STWX:
134                         rs = get_rs(inst);
135                         emulated = kvmppc_handle_store(run, vcpu,
136                                                        vcpu->arch.gpr[rs],
137                                                        4, 1);
138                         break;
139
140                 case OP_31_XOP_STBX:
141                         rs = get_rs(inst);
142                         emulated = kvmppc_handle_store(run, vcpu,
143                                                        vcpu->arch.gpr[rs],
144                                                        1, 1);
145                         break;
146
147                 case OP_31_XOP_STBUX:
148                         rs = get_rs(inst);
149                         ra = get_ra(inst);
150                         rb = get_rb(inst);
151
152                         ea = vcpu->arch.gpr[rb];
153                         if (ra)
154                                 ea += vcpu->arch.gpr[ra];
155
156                         emulated = kvmppc_handle_store(run, vcpu,
157                                                        vcpu->arch.gpr[rs],
158                                                        1, 1);
159                         vcpu->arch.gpr[rs] = ea;
160                         break;
161
162                 case OP_31_XOP_LHZX:
163                         rt = get_rt(inst);
164                         emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
165                         break;
166
167                 case OP_31_XOP_LHZUX:
168                         rt = get_rt(inst);
169                         ra = get_ra(inst);
170                         rb = get_rb(inst);
171
172                         ea = vcpu->arch.gpr[rb];
173                         if (ra)
174                                 ea += vcpu->arch.gpr[ra];
175
176                         emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
177                         vcpu->arch.gpr[ra] = ea;
178                         break;
179
180                 case OP_31_XOP_MFSPR:
181                         sprn = get_sprn(inst);
182                         rt = get_rt(inst);
183
184                         switch (sprn) {
185                         case SPRN_SRR0:
186                                 vcpu->arch.gpr[rt] = vcpu->arch.srr0; break;
187                         case SPRN_SRR1:
188                                 vcpu->arch.gpr[rt] = vcpu->arch.srr1; break;
189                         case SPRN_PVR:
190                                 vcpu->arch.gpr[rt] = vcpu->arch.pvr; break;
191
192                         /* Note: mftb and TBRL/TBWL are user-accessible, so
193                          * the guest can always access the real TB anyways.
194                          * In fact, we probably will never see these traps. */
195                         case SPRN_TBWL:
196                                 vcpu->arch.gpr[rt] = mftbl(); break;
197                         case SPRN_TBWU:
198                                 vcpu->arch.gpr[rt] = mftbu(); break;
199
200                         case SPRN_SPRG0:
201                                 vcpu->arch.gpr[rt] = vcpu->arch.sprg0; break;
202                         case SPRN_SPRG1:
203                                 vcpu->arch.gpr[rt] = vcpu->arch.sprg1; break;
204                         case SPRN_SPRG2:
205                                 vcpu->arch.gpr[rt] = vcpu->arch.sprg2; break;
206                         case SPRN_SPRG3:
207                                 vcpu->arch.gpr[rt] = vcpu->arch.sprg3; break;
208                         /* Note: SPRG4-7 are user-readable, so we don't get
209                          * a trap. */
210
211                         default:
212                                 emulated = kvmppc_core_emulate_mfspr(vcpu, sprn, rt);
213                                 if (emulated == EMULATE_FAIL) {
214                                         printk("mfspr: unknown spr %x\n", sprn);
215                                         vcpu->arch.gpr[rt] = 0;
216                                 }
217                                 break;
218                         }
219                         break;
220
221                 case OP_31_XOP_STHX:
222                         rs = get_rs(inst);
223                         ra = get_ra(inst);
224                         rb = get_rb(inst);
225
226                         emulated = kvmppc_handle_store(run, vcpu,
227                                                        vcpu->arch.gpr[rs],
228                                                        2, 1);
229                         break;
230
231                 case OP_31_XOP_STHUX:
232                         rs = get_rs(inst);
233                         ra = get_ra(inst);
234                         rb = get_rb(inst);
235
236                         ea = vcpu->arch.gpr[rb];
237                         if (ra)
238                                 ea += vcpu->arch.gpr[ra];
239
240                         emulated = kvmppc_handle_store(run, vcpu,
241                                                        vcpu->arch.gpr[rs],
242                                                        2, 1);
243                         vcpu->arch.gpr[ra] = ea;
244                         break;
245
246                 case OP_31_XOP_MTSPR:
247                         sprn = get_sprn(inst);
248                         rs = get_rs(inst);
249                         switch (sprn) {
250                         case SPRN_SRR0:
251                                 vcpu->arch.srr0 = vcpu->arch.gpr[rs]; break;
252                         case SPRN_SRR1:
253                                 vcpu->arch.srr1 = vcpu->arch.gpr[rs]; break;
254
255                         /* XXX We need to context-switch the timebase for
256                          * watchdog and FIT. */
257                         case SPRN_TBWL: break;
258                         case SPRN_TBWU: break;
259
260                         case SPRN_DEC:
261                                 vcpu->arch.dec = vcpu->arch.gpr[rs];
262                                 kvmppc_emulate_dec(vcpu);
263                                 break;
264
265                         case SPRN_SPRG0:
266                                 vcpu->arch.sprg0 = vcpu->arch.gpr[rs]; break;
267                         case SPRN_SPRG1:
268                                 vcpu->arch.sprg1 = vcpu->arch.gpr[rs]; break;
269                         case SPRN_SPRG2:
270                                 vcpu->arch.sprg2 = vcpu->arch.gpr[rs]; break;
271                         case SPRN_SPRG3:
272                                 vcpu->arch.sprg3 = vcpu->arch.gpr[rs]; break;
273
274                         default:
275                                 emulated = kvmppc_core_emulate_mtspr(vcpu, sprn, rs);
276                                 if (emulated == EMULATE_FAIL)
277                                         printk("mtspr: unknown spr %x\n", sprn);
278                                 break;
279                         }
280                         break;
281
282                 case OP_31_XOP_DCBI:
283                         /* Do nothing. The guest is performing dcbi because
284                          * hardware DMA is not snooped by the dcache, but
285                          * emulated DMA either goes through the dcache as
286                          * normal writes, or the host kernel has handled dcache
287                          * coherence. */
288                         break;
289
290                 case OP_31_XOP_LWBRX:
291                         rt = get_rt(inst);
292                         emulated = kvmppc_handle_load(run, vcpu, rt, 4, 0);
293                         break;
294
295                 case OP_31_XOP_TLBSYNC:
296                         break;
297
298                 case OP_31_XOP_STWBRX:
299                         rs = get_rs(inst);
300                         ra = get_ra(inst);
301                         rb = get_rb(inst);
302
303                         emulated = kvmppc_handle_store(run, vcpu,
304                                                        vcpu->arch.gpr[rs],
305                                                        4, 0);
306                         break;
307
308                 case OP_31_XOP_LHBRX:
309                         rt = get_rt(inst);
310                         emulated = kvmppc_handle_load(run, vcpu, rt, 2, 0);
311                         break;
312
313                 case OP_31_XOP_STHBRX:
314                         rs = get_rs(inst);
315                         ra = get_ra(inst);
316                         rb = get_rb(inst);
317
318                         emulated = kvmppc_handle_store(run, vcpu,
319                                                        vcpu->arch.gpr[rs],
320                                                        2, 0);
321                         break;
322
323                 default:
324                         /* Attempt core-specific emulation below. */
325                         emulated = EMULATE_FAIL;
326                 }
327                 break;
328
329         case OP_LWZ:
330                 rt = get_rt(inst);
331                 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
332                 break;
333
334         case OP_LWZU:
335                 ra = get_ra(inst);
336                 rt = get_rt(inst);
337                 emulated = kvmppc_handle_load(run, vcpu, rt, 4, 1);
338                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
339                 break;
340
341         case OP_LBZ:
342                 rt = get_rt(inst);
343                 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
344                 break;
345
346         case OP_LBZU:
347                 ra = get_ra(inst);
348                 rt = get_rt(inst);
349                 emulated = kvmppc_handle_load(run, vcpu, rt, 1, 1);
350                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
351                 break;
352
353         case OP_STW:
354                 rs = get_rs(inst);
355                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
356                                                4, 1);
357                 break;
358
359         case OP_STWU:
360                 ra = get_ra(inst);
361                 rs = get_rs(inst);
362                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
363                                                4, 1);
364                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
365                 break;
366
367         case OP_STB:
368                 rs = get_rs(inst);
369                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
370                                                1, 1);
371                 break;
372
373         case OP_STBU:
374                 ra = get_ra(inst);
375                 rs = get_rs(inst);
376                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
377                                                1, 1);
378                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
379                 break;
380
381         case OP_LHZ:
382                 rt = get_rt(inst);
383                 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
384                 break;
385
386         case OP_LHZU:
387                 ra = get_ra(inst);
388                 rt = get_rt(inst);
389                 emulated = kvmppc_handle_load(run, vcpu, rt, 2, 1);
390                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
391                 break;
392
393         case OP_STH:
394                 rs = get_rs(inst);
395                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
396                                                2, 1);
397                 break;
398
399         case OP_STHU:
400                 ra = get_ra(inst);
401                 rs = get_rs(inst);
402                 emulated = kvmppc_handle_store(run, vcpu, vcpu->arch.gpr[rs],
403                                                2, 1);
404                 vcpu->arch.gpr[ra] = vcpu->arch.paddr_accessed;
405                 break;
406
407         default:
408                 emulated = EMULATE_FAIL;
409         }
410
411         if (emulated == EMULATE_FAIL) {
412                 emulated = kvmppc_core_emulate_op(run, vcpu, inst, &advance);
413                 if (emulated == EMULATE_FAIL) {
414                         advance = 0;
415                         printk(KERN_ERR "Couldn't emulate instruction 0x%08x "
416                                "(op %d xop %d)\n", inst, get_op(inst), get_xop(inst));
417                 }
418         }
419
420         KVMTRACE_3D(PPC_INSTR, vcpu, inst, (int)vcpu->arch.pc, emulated, entryexit);
421
422         if (advance)
423                 vcpu->arch.pc += 4; /* Advance past emulated instruction. */
424
425         return emulated;
426 }