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1/*
2 * arch/arm/kernel/kprobes-thumb.c
3 *
4 * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/kernel.h>
12#include <linux/kprobes.h>
13#include <linux/module.h>
14
15#include "kprobes.h"
16
17
18/*
19 * True if current instruction is in an IT block.
20 */
21#define in_it_block(cpsr) ((cpsr & 0x06000c00) != 0x00000000)
22
23/*
24 * Return the condition code to check for the currently executing instruction.
25 * This is in ITSTATE<7:4> which is in CPSR<15:12> but is only valid if
26 * in_it_block returns true.
27 */
28#define current_cond(cpsr) ((cpsr >> 12) & 0xf)
29
30/*
31 * Return the PC value for a probe in thumb code.
32 * This is the address of the probed instruction plus 4.
33 * We subtract one because the address will have bit zero set to indicate
34 * a pointer to thumb code.
35 */
36static inline unsigned long __kprobes thumb_probe_pc(struct kprobe *p)
37{
38 return (unsigned long)p->addr - 1 + 4;
39}
40
41static void __kprobes
42t32_simulate_table_branch(struct kprobe *p, struct pt_regs *regs)
43{
44 kprobe_opcode_t insn = p->opcode;
45 unsigned long pc = thumb_probe_pc(p);
46 int rn = (insn >> 16) & 0xf;
47 int rm = insn & 0xf;
48
49 unsigned long rnv = (rn == 15) ? pc : regs->uregs[rn];
50 unsigned long rmv = regs->uregs[rm];
51 unsigned int halfwords;
52
53 if (insn & 0x10) /* TBH */
54 halfwords = ((u16 *)rnv)[rmv];
55 else /* TBB */
56 halfwords = ((u8 *)rnv)[rmv];
57
58 regs->ARM_pc = pc + 2 * halfwords;
59}
60
61static void __kprobes
62t32_simulate_mrs(struct kprobe *p, struct pt_regs *regs)
63{
64 kprobe_opcode_t insn = p->opcode;
65 int rd = (insn >> 8) & 0xf;
66 unsigned long mask = 0xf8ff03df; /* Mask out execution state */
67 regs->uregs[rd] = regs->ARM_cpsr & mask;
68}
69
70static void __kprobes
71t32_simulate_cond_branch(struct kprobe *p, struct pt_regs *regs)
72{
73 kprobe_opcode_t insn = p->opcode;
74 unsigned long pc = thumb_probe_pc(p);
75
76 long offset = insn & 0x7ff; /* imm11 */
77 offset += (insn & 0x003f0000) >> 5; /* imm6 */
78 offset += (insn & 0x00002000) << 4; /* J1 */
79 offset += (insn & 0x00000800) << 7; /* J2 */
80 offset -= (insn & 0x04000000) >> 7; /* Apply sign bit */
81
82 regs->ARM_pc = pc + (offset * 2);
83}
84
85static enum kprobe_insn __kprobes
86t32_decode_cond_branch(kprobe_opcode_t insn, struct arch_specific_insn *asi)
87{
88 int cc = (insn >> 22) & 0xf;
89 asi->insn_check_cc = kprobe_condition_checks[cc];
90 asi->insn_handler = t32_simulate_cond_branch;
91 return INSN_GOOD_NO_SLOT;
92}
93
94static void __kprobes
95t32_simulate_branch(struct kprobe *p, struct pt_regs *regs)
96{
97 kprobe_opcode_t insn = p->opcode;
98 unsigned long pc = thumb_probe_pc(p);
99
100 long offset = insn & 0x7ff; /* imm11 */
101 offset += (insn & 0x03ff0000) >> 5; /* imm10 */
102 offset += (insn & 0x00002000) << 9; /* J1 */
103 offset += (insn & 0x00000800) << 10; /* J2 */
104 if (insn & 0x04000000)
105 offset -= 0x00800000; /* Apply sign bit */
106 else
107 offset ^= 0x00600000; /* Invert J1 and J2 */
108
109 if (insn & (1 << 14)) {
110 /* BL or BLX */
111 regs->ARM_lr = (unsigned long)p->addr + 4;
112 if (!(insn & (1 << 12))) {
113 /* BLX so switch to ARM mode */
114 regs->ARM_cpsr &= ~PSR_T_BIT;
115 pc &= ~3;
116 }
117 }
118
119 regs->ARM_pc = pc + (offset * 2);
120}
121
122static void __kprobes
123t32_simulate_ldr_literal(struct kprobe *p, struct pt_regs *regs)
124{
125 kprobe_opcode_t insn = p->opcode;
126 unsigned long addr = thumb_probe_pc(p) & ~3;
127 int rt = (insn >> 12) & 0xf;
128 unsigned long rtv;
129
130 long offset = insn & 0xfff;
131 if (insn & 0x00800000)
132 addr += offset;
133 else
134 addr -= offset;
135
136 if (insn & 0x00400000) {
137 /* LDR */
138 rtv = *(unsigned long *)addr;
139 if (rt == 15) {
140 bx_write_pc(rtv, regs);
141 return;
142 }
143 } else if (insn & 0x00200000) {
144 /* LDRH */
145 if (insn & 0x01000000)
146 rtv = *(s16 *)addr;
147 else
148 rtv = *(u16 *)addr;
149 } else {
150 /* LDRB */
151 if (insn & 0x01000000)
152 rtv = *(s8 *)addr;
153 else
154 rtv = *(u8 *)addr;
155 }
156
157 regs->uregs[rt] = rtv;
158}
159
160static enum kprobe_insn __kprobes
161t32_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi)
162{
163 enum kprobe_insn ret = kprobe_decode_ldmstm(insn, asi);
164
165 /* Fixup modified instruction to have halfwords in correct order...*/
166 insn = asi->insn[0];
167 ((u16 *)asi->insn)[0] = insn >> 16;
168 ((u16 *)asi->insn)[1] = insn & 0xffff;
169
170 return ret;
171}
172
173static void __kprobes
174t32_emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs)
175{
176 kprobe_opcode_t insn = p->opcode;
177 unsigned long pc = thumb_probe_pc(p) & ~3;
178 int rt1 = (insn >> 12) & 0xf;
179 int rt2 = (insn >> 8) & 0xf;
180 int rn = (insn >> 16) & 0xf;
181
182 register unsigned long rt1v asm("r0") = regs->uregs[rt1];
183 register unsigned long rt2v asm("r1") = regs->uregs[rt2];
184 register unsigned long rnv asm("r2") = (rn == 15) ? pc
185 : regs->uregs[rn];
186
187 __asm__ __volatile__ (
188 "blx %[fn]"
189 : "=r" (rt1v), "=r" (rt2v), "=r" (rnv)
190 : "0" (rt1v), "1" (rt2v), "2" (rnv), [fn] "r" (p->ainsn.insn_fn)
191 : "lr", "memory", "cc"
192 );
193
194 if (rn != 15)
195 regs->uregs[rn] = rnv; /* Writeback base register */
196 regs->uregs[rt1] = rt1v;
197 regs->uregs[rt2] = rt2v;
198}
199
200static void __kprobes
201t32_emulate_ldrstr(struct kprobe *p, struct pt_regs *regs)
202{
203 kprobe_opcode_t insn = p->opcode;
204 int rt = (insn >> 12) & 0xf;
205 int rn = (insn >> 16) & 0xf;
206 int rm = insn & 0xf;
207
208 register unsigned long rtv asm("r0") = regs->uregs[rt];
209 register unsigned long rnv asm("r2") = regs->uregs[rn];
210 register unsigned long rmv asm("r3") = regs->uregs[rm];
211
212 __asm__ __volatile__ (
213 "blx %[fn]"
214 : "=r" (rtv), "=r" (rnv)
215 : "0" (rtv), "1" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
216 : "lr", "memory", "cc"
217 );
218
219 regs->uregs[rn] = rnv; /* Writeback base register */
220 if (rt == 15) /* Can't be true for a STR as they aren't allowed */
221 bx_write_pc(rtv, regs);
222 else
223 regs->uregs[rt] = rtv;
224}
225
226static void __kprobes
227t32_emulate_rd8rn16rm0_rwflags(struct kprobe *p, struct pt_regs *regs)
228{
229 kprobe_opcode_t insn = p->opcode;
230 int rd = (insn >> 8) & 0xf;
231 int rn = (insn >> 16) & 0xf;
232 int rm = insn & 0xf;
233
234 register unsigned long rdv asm("r1") = regs->uregs[rd];
235 register unsigned long rnv asm("r2") = regs->uregs[rn];
236 register unsigned long rmv asm("r3") = regs->uregs[rm];
237 unsigned long cpsr = regs->ARM_cpsr;
238
239 __asm__ __volatile__ (
240 "msr cpsr_fs, %[cpsr] \n\t"
241 "blx %[fn] \n\t"
242 "mrs %[cpsr], cpsr \n\t"
243 : "=r" (rdv), [cpsr] "=r" (cpsr)
244 : "0" (rdv), "r" (rnv), "r" (rmv),
245 "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
246 : "lr", "memory", "cc"
247 );
248
249 regs->uregs[rd] = rdv;
250 regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
251}
252
253static void __kprobes
254t32_emulate_rd8pc16_noflags(struct kprobe *p, struct pt_regs *regs)
255{
256 kprobe_opcode_t insn = p->opcode;
257 unsigned long pc = thumb_probe_pc(p);
258 int rd = (insn >> 8) & 0xf;
259
260 register unsigned long rdv asm("r1") = regs->uregs[rd];
261 register unsigned long rnv asm("r2") = pc & ~3;
262
263 __asm__ __volatile__ (
264 "blx %[fn]"
265 : "=r" (rdv)
266 : "0" (rdv), "r" (rnv), [fn] "r" (p->ainsn.insn_fn)
267 : "lr", "memory", "cc"
268 );
269
270 regs->uregs[rd] = rdv;
271}
272
273static void __kprobes
274t32_emulate_rd8rn16_noflags(struct kprobe *p, struct pt_regs *regs)
275{
276 kprobe_opcode_t insn = p->opcode;
277 int rd = (insn >> 8) & 0xf;
278 int rn = (insn >> 16) & 0xf;
279
280 register unsigned long rdv asm("r1") = regs->uregs[rd];
281 register unsigned long rnv asm("r2") = regs->uregs[rn];
282
283 __asm__ __volatile__ (
284 "blx %[fn]"
285 : "=r" (rdv)
286 : "0" (rdv), "r" (rnv), [fn] "r" (p->ainsn.insn_fn)
287 : "lr", "memory", "cc"
288 );
289
290 regs->uregs[rd] = rdv;
291}
292
293static void __kprobes
294t32_emulate_rdlo12rdhi8rn16rm0_noflags(struct kprobe *p, struct pt_regs *regs)
295{
296 kprobe_opcode_t insn = p->opcode;
297 int rdlo = (insn >> 12) & 0xf;
298 int rdhi = (insn >> 8) & 0xf;
299 int rn = (insn >> 16) & 0xf;
300 int rm = insn & 0xf;
301
302 register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
303 register unsigned long rdhiv asm("r1") = regs->uregs[rdhi];
304 register unsigned long rnv asm("r2") = regs->uregs[rn];
305 register unsigned long rmv asm("r3") = regs->uregs[rm];
306
307 __asm__ __volatile__ (
308 "blx %[fn]"
309 : "=r" (rdlov), "=r" (rdhiv)
310 : "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
311 [fn] "r" (p->ainsn.insn_fn)
312 : "lr", "memory", "cc"
313 );
314
315 regs->uregs[rdlo] = rdlov;
316 regs->uregs[rdhi] = rdhiv;
317}
318
319/* These emulation encodings are functionally equivalent... */
320#define t32_emulate_rd8rn16rm0ra12_noflags \
321 t32_emulate_rdlo12rdhi8rn16rm0_noflags
322
323static const union decode_item t32_table_1110_100x_x0xx[] = {
324 /* Load/store multiple instructions */
325
326 /* Rn is PC 1110 100x x0xx 1111 xxxx xxxx xxxx xxxx */
327 DECODE_REJECT (0xfe4f0000, 0xe80f0000),
328
329 /* SRS 1110 1000 00x0 xxxx xxxx xxxx xxxx xxxx */
330 /* RFE 1110 1000 00x1 xxxx xxxx xxxx xxxx xxxx */
331 DECODE_REJECT (0xffc00000, 0xe8000000),
332 /* SRS 1110 1001 10x0 xxxx xxxx xxxx xxxx xxxx */
333 /* RFE 1110 1001 10x1 xxxx xxxx xxxx xxxx xxxx */
334 DECODE_REJECT (0xffc00000, 0xe9800000),
335
336 /* STM Rn, {...pc} 1110 100x x0x0 xxxx 1xxx xxxx xxxx xxxx */
337 DECODE_REJECT (0xfe508000, 0xe8008000),
338 /* LDM Rn, {...lr,pc} 1110 100x x0x1 xxxx 11xx xxxx xxxx xxxx */
339 DECODE_REJECT (0xfe50c000, 0xe810c000),
340 /* LDM/STM Rn, {...sp} 1110 100x x0xx xxxx xx1x xxxx xxxx xxxx */
341 DECODE_REJECT (0xfe402000, 0xe8002000),
342
343 /* STMIA 1110 1000 10x0 xxxx xxxx xxxx xxxx xxxx */
344 /* LDMIA 1110 1000 10x1 xxxx xxxx xxxx xxxx xxxx */
345 /* STMDB 1110 1001 00x0 xxxx xxxx xxxx xxxx xxxx */
346 /* LDMDB 1110 1001 00x1 xxxx xxxx xxxx xxxx xxxx */
347 DECODE_CUSTOM (0xfe400000, 0xe8000000, t32_decode_ldmstm),
348
349 DECODE_END
350};
351
352static const union decode_item t32_table_1110_100x_x1xx[] = {
353 /* Load/store dual, load/store exclusive, table branch */
354
355 /* STRD (immediate) 1110 1000 x110 xxxx xxxx xxxx xxxx xxxx */
356 /* LDRD (immediate) 1110 1000 x111 xxxx xxxx xxxx xxxx xxxx */
357 DECODE_OR (0xff600000, 0xe8600000),
358 /* STRD (immediate) 1110 1001 x1x0 xxxx xxxx xxxx xxxx xxxx */
359 /* LDRD (immediate) 1110 1001 x1x1 xxxx xxxx xxxx xxxx xxxx */
360 DECODE_EMULATEX (0xff400000, 0xe9400000, t32_emulate_ldrdstrd,
361 REGS(NOPCWB, NOSPPC, NOSPPC, 0, 0)),
362
363 /* TBB 1110 1000 1101 xxxx xxxx xxxx 0000 xxxx */
364 /* TBH 1110 1000 1101 xxxx xxxx xxxx 0001 xxxx */
365 DECODE_SIMULATEX(0xfff000e0, 0xe8d00000, t32_simulate_table_branch,
366 REGS(NOSP, 0, 0, 0, NOSPPC)),
367
368 /* STREX 1110 1000 0100 xxxx xxxx xxxx xxxx xxxx */
369 /* LDREX 1110 1000 0101 xxxx xxxx xxxx xxxx xxxx */
370 /* STREXB 1110 1000 1100 xxxx xxxx xxxx 0100 xxxx */
371 /* STREXH 1110 1000 1100 xxxx xxxx xxxx 0101 xxxx */
372 /* STREXD 1110 1000 1100 xxxx xxxx xxxx 0111 xxxx */
373 /* LDREXB 1110 1000 1101 xxxx xxxx xxxx 0100 xxxx */
374 /* LDREXH 1110 1000 1101 xxxx xxxx xxxx 0101 xxxx */
375 /* LDREXD 1110 1000 1101 xxxx xxxx xxxx 0111 xxxx */
376 /* And unallocated instructions... */
377 DECODE_END
378};
379
380static const union decode_item t32_table_1110_101x[] = {
381 /* Data-processing (shifted register) */
382
383 /* TST 1110 1010 0001 xxxx xxxx 1111 xxxx xxxx */
384 /* TEQ 1110 1010 1001 xxxx xxxx 1111 xxxx xxxx */
385 DECODE_EMULATEX (0xff700f00, 0xea100f00, t32_emulate_rd8rn16rm0_rwflags,
386 REGS(NOSPPC, 0, 0, 0, NOSPPC)),
387
388 /* CMN 1110 1011 0001 xxxx xxxx 1111 xxxx xxxx */
389 DECODE_OR (0xfff00f00, 0xeb100f00),
390 /* CMP 1110 1011 1011 xxxx xxxx 1111 xxxx xxxx */
391 DECODE_EMULATEX (0xfff00f00, 0xebb00f00, t32_emulate_rd8rn16rm0_rwflags,
392 REGS(NOPC, 0, 0, 0, NOSPPC)),
393
394 /* MOV 1110 1010 010x 1111 xxxx xxxx xxxx xxxx */
395 /* MVN 1110 1010 011x 1111 xxxx xxxx xxxx xxxx */
396 DECODE_EMULATEX (0xffcf0000, 0xea4f0000, t32_emulate_rd8rn16rm0_rwflags,
397 REGS(0, 0, NOSPPC, 0, NOSPPC)),
398
399 /* ??? 1110 1010 101x xxxx xxxx xxxx xxxx xxxx */
400 /* ??? 1110 1010 111x xxxx xxxx xxxx xxxx xxxx */
401 DECODE_REJECT (0xffa00000, 0xeaa00000),
402 /* ??? 1110 1011 001x xxxx xxxx xxxx xxxx xxxx */
403 DECODE_REJECT (0xffe00000, 0xeb200000),
404 /* ??? 1110 1011 100x xxxx xxxx xxxx xxxx xxxx */
405 DECODE_REJECT (0xffe00000, 0xeb800000),
406 /* ??? 1110 1011 111x xxxx xxxx xxxx xxxx xxxx */
407 DECODE_REJECT (0xffe00000, 0xebe00000),
408
409 /* ADD/SUB SP, SP, Rm, LSL #0..3 */
410 /* 1110 1011 x0xx 1101 x000 1101 xx00 xxxx */
411 DECODE_EMULATEX (0xff4f7f30, 0xeb0d0d00, t32_emulate_rd8rn16rm0_rwflags,
412 REGS(SP, 0, SP, 0, NOSPPC)),
413
414 /* ADD/SUB SP, SP, Rm, shift */
415 /* 1110 1011 x0xx 1101 xxxx 1101 xxxx xxxx */
416 DECODE_REJECT (0xff4f0f00, 0xeb0d0d00),
417
418 /* ADD/SUB Rd, SP, Rm, shift */
419 /* 1110 1011 x0xx 1101 xxxx xxxx xxxx xxxx */
420 DECODE_EMULATEX (0xff4f0000, 0xeb0d0000, t32_emulate_rd8rn16rm0_rwflags,
421 REGS(SP, 0, NOPC, 0, NOSPPC)),
422
423 /* AND 1110 1010 000x xxxx xxxx xxxx xxxx xxxx */
424 /* BIC 1110 1010 001x xxxx xxxx xxxx xxxx xxxx */
425 /* ORR 1110 1010 010x xxxx xxxx xxxx xxxx xxxx */
426 /* ORN 1110 1010 011x xxxx xxxx xxxx xxxx xxxx */
427 /* EOR 1110 1010 100x xxxx xxxx xxxx xxxx xxxx */
428 /* PKH 1110 1010 110x xxxx xxxx xxxx xxxx xxxx */
429 /* ADD 1110 1011 000x xxxx xxxx xxxx xxxx xxxx */
430 /* ADC 1110 1011 010x xxxx xxxx xxxx xxxx xxxx */
431 /* SBC 1110 1011 011x xxxx xxxx xxxx xxxx xxxx */
432 /* SUB 1110 1011 101x xxxx xxxx xxxx xxxx xxxx */
433 /* RSB 1110 1011 110x xxxx xxxx xxxx xxxx xxxx */
434 DECODE_EMULATEX (0xfe000000, 0xea000000, t32_emulate_rd8rn16rm0_rwflags,
435 REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)),
436
437 DECODE_END
438};
439
440static const union decode_item t32_table_1111_0x0x___0[] = {
441 /* Data-processing (modified immediate) */
442
443 /* TST 1111 0x00 0001 xxxx 0xxx 1111 xxxx xxxx */
444 /* TEQ 1111 0x00 1001 xxxx 0xxx 1111 xxxx xxxx */
445 DECODE_EMULATEX (0xfb708f00, 0xf0100f00, t32_emulate_rd8rn16rm0_rwflags,
446 REGS(NOSPPC, 0, 0, 0, 0)),
447
448 /* CMN 1111 0x01 0001 xxxx 0xxx 1111 xxxx xxxx */
449 DECODE_OR (0xfbf08f00, 0xf1100f00),
450 /* CMP 1111 0x01 1011 xxxx 0xxx 1111 xxxx xxxx */
451 DECODE_EMULATEX (0xfbf08f00, 0xf1b00f00, t32_emulate_rd8rn16rm0_rwflags,
452 REGS(NOPC, 0, 0, 0, 0)),
453
454 /* MOV 1111 0x00 010x 1111 0xxx xxxx xxxx xxxx */
455 /* MVN 1111 0x00 011x 1111 0xxx xxxx xxxx xxxx */
456 DECODE_EMULATEX (0xfbcf8000, 0xf04f0000, t32_emulate_rd8rn16rm0_rwflags,
457 REGS(0, 0, NOSPPC, 0, 0)),
458
459 /* ??? 1111 0x00 101x xxxx 0xxx xxxx xxxx xxxx */
460 DECODE_REJECT (0xfbe08000, 0xf0a00000),
461 /* ??? 1111 0x00 110x xxxx 0xxx xxxx xxxx xxxx */
462 /* ??? 1111 0x00 111x xxxx 0xxx xxxx xxxx xxxx */
463 DECODE_REJECT (0xfbc08000, 0xf0c00000),
464 /* ??? 1111 0x01 001x xxxx 0xxx xxxx xxxx xxxx */
465 DECODE_REJECT (0xfbe08000, 0xf1200000),
466 /* ??? 1111 0x01 100x xxxx 0xxx xxxx xxxx xxxx */
467 DECODE_REJECT (0xfbe08000, 0xf1800000),
468 /* ??? 1111 0x01 111x xxxx 0xxx xxxx xxxx xxxx */
469 DECODE_REJECT (0xfbe08000, 0xf1e00000),
470
471 /* ADD Rd, SP, #imm 1111 0x01 000x 1101 0xxx xxxx xxxx xxxx */
472 /* SUB Rd, SP, #imm 1111 0x01 101x 1101 0xxx xxxx xxxx xxxx */
473 DECODE_EMULATEX (0xfb4f8000, 0xf10d0000, t32_emulate_rd8rn16rm0_rwflags,
474 REGS(SP, 0, NOPC, 0, 0)),
475
476 /* AND 1111 0x00 000x xxxx 0xxx xxxx xxxx xxxx */
477 /* BIC 1111 0x00 001x xxxx 0xxx xxxx xxxx xxxx */
478 /* ORR 1111 0x00 010x xxxx 0xxx xxxx xxxx xxxx */
479 /* ORN 1111 0x00 011x xxxx 0xxx xxxx xxxx xxxx */
480 /* EOR 1111 0x00 100x xxxx 0xxx xxxx xxxx xxxx */
481 /* ADD 1111 0x01 000x xxxx 0xxx xxxx xxxx xxxx */
482 /* ADC 1111 0x01 010x xxxx 0xxx xxxx xxxx xxxx */
483 /* SBC 1111 0x01 011x xxxx 0xxx xxxx xxxx xxxx */
484 /* SUB 1111 0x01 101x xxxx 0xxx xxxx xxxx xxxx */
485 /* RSB 1111 0x01 110x xxxx 0xxx xxxx xxxx xxxx */
486 DECODE_EMULATEX (0xfa008000, 0xf0000000, t32_emulate_rd8rn16rm0_rwflags,
487 REGS(NOSPPC, 0, NOSPPC, 0, 0)),
488
489 DECODE_END
490};
491
492static const union decode_item t32_table_1111_0x1x___0[] = {
493 /* Data-processing (plain binary immediate) */
494
495 /* ADDW Rd, PC, #imm 1111 0x10 0000 1111 0xxx xxxx xxxx xxxx */
496 DECODE_OR (0xfbff8000, 0xf20f0000),
497 /* SUBW Rd, PC, #imm 1111 0x10 1010 1111 0xxx xxxx xxxx xxxx */
498 DECODE_EMULATEX (0xfbff8000, 0xf2af0000, t32_emulate_rd8pc16_noflags,
499 REGS(PC, 0, NOSPPC, 0, 0)),
500
501 /* ADDW SP, SP, #imm 1111 0x10 0000 1101 0xxx 1101 xxxx xxxx */
502 DECODE_OR (0xfbff8f00, 0xf20d0d00),
503 /* SUBW SP, SP, #imm 1111 0x10 1010 1101 0xxx 1101 xxxx xxxx */
504 DECODE_EMULATEX (0xfbff8f00, 0xf2ad0d00, t32_emulate_rd8rn16_noflags,
505 REGS(SP, 0, SP, 0, 0)),
506
507 /* ADDW 1111 0x10 0000 xxxx 0xxx xxxx xxxx xxxx */
508 DECODE_OR (0xfbf08000, 0xf2000000),
509 /* SUBW 1111 0x10 1010 xxxx 0xxx xxxx xxxx xxxx */
510 DECODE_EMULATEX (0xfbf08000, 0xf2a00000, t32_emulate_rd8rn16_noflags,
511 REGS(NOPCX, 0, NOSPPC, 0, 0)),
512
513 /* MOVW 1111 0x10 0100 xxxx 0xxx xxxx xxxx xxxx */
514 /* MOVT 1111 0x10 1100 xxxx 0xxx xxxx xxxx xxxx */
515 DECODE_EMULATEX (0xfb708000, 0xf2400000, t32_emulate_rd8rn16_noflags,
516 REGS(0, 0, NOSPPC, 0, 0)),
517
518 /* SSAT16 1111 0x11 0010 xxxx 0000 xxxx 00xx xxxx */
519 /* SSAT 1111 0x11 00x0 xxxx 0xxx xxxx xxxx xxxx */
520 /* USAT16 1111 0x11 1010 xxxx 0000 xxxx 00xx xxxx */
521 /* USAT 1111 0x11 10x0 xxxx 0xxx xxxx xxxx xxxx */
522 DECODE_EMULATEX (0xfb508000, 0xf3000000, t32_emulate_rd8rn16rm0_rwflags,
523 REGS(NOSPPC, 0, NOSPPC, 0, 0)),
524
525 /* SFBX 1111 0x11 0100 xxxx 0xxx xxxx xxxx xxxx */
526 /* UFBX 1111 0x11 1100 xxxx 0xxx xxxx xxxx xxxx */
527 DECODE_EMULATEX (0xfb708000, 0xf3400000, t32_emulate_rd8rn16_noflags,
528 REGS(NOSPPC, 0, NOSPPC, 0, 0)),
529
530 /* BFC 1111 0x11 0110 1111 0xxx xxxx xxxx xxxx */
531 DECODE_EMULATEX (0xfbff8000, 0xf36f0000, t32_emulate_rd8rn16_noflags,
532 REGS(0, 0, NOSPPC, 0, 0)),
533
534 /* BFI 1111 0x11 0110 xxxx 0xxx xxxx xxxx xxxx */
535 DECODE_EMULATEX (0xfbf08000, 0xf3600000, t32_emulate_rd8rn16_noflags,
536 REGS(NOSPPCX, 0, NOSPPC, 0, 0)),
537
538 DECODE_END
539};
540
541static const union decode_item t32_table_1111_0xxx___1[] = {
542 /* Branches and miscellaneous control */
543
544 /* YIELD 1111 0011 1010 xxxx 10x0 x000 0000 0001 */
545 DECODE_OR (0xfff0d7ff, 0xf3a08001),
546 /* SEV 1111 0011 1010 xxxx 10x0 x000 0000 0100 */
547 DECODE_EMULATE (0xfff0d7ff, 0xf3a08004, kprobe_emulate_none),
548 /* NOP 1111 0011 1010 xxxx 10x0 x000 0000 0000 */
549 /* WFE 1111 0011 1010 xxxx 10x0 x000 0000 0010 */
550 /* WFI 1111 0011 1010 xxxx 10x0 x000 0000 0011 */
551 DECODE_SIMULATE (0xfff0d7fc, 0xf3a08000, kprobe_simulate_nop),
552
553 /* MRS Rd, CPSR 1111 0011 1110 xxxx 10x0 xxxx xxxx xxxx */
554 DECODE_SIMULATEX(0xfff0d000, 0xf3e08000, t32_simulate_mrs,
555 REGS(0, 0, NOSPPC, 0, 0)),
556
557 /*
558 * Unsupported instructions
559 * 1111 0x11 1xxx xxxx 10x0 xxxx xxxx xxxx
560 *
561 * MSR 1111 0011 100x xxxx 10x0 xxxx xxxx xxxx
562 * DBG hint 1111 0011 1010 xxxx 10x0 x000 1111 xxxx
563 * Unallocated hints 1111 0011 1010 xxxx 10x0 x000 xxxx xxxx
564 * CPS 1111 0011 1010 xxxx 10x0 xxxx xxxx xxxx
565 * CLREX/DSB/DMB/ISB 1111 0011 1011 xxxx 10x0 xxxx xxxx xxxx
566 * BXJ 1111 0011 1100 xxxx 10x0 xxxx xxxx xxxx
567 * SUBS PC,LR,#<imm8> 1111 0011 1101 xxxx 10x0 xxxx xxxx xxxx
568 * MRS Rd, SPSR 1111 0011 1111 xxxx 10x0 xxxx xxxx xxxx
569 * SMC 1111 0111 1111 xxxx 1000 xxxx xxxx xxxx
570 * UNDEFINED 1111 0111 1111 xxxx 1010 xxxx xxxx xxxx
571 * ??? 1111 0111 1xxx xxxx 1010 xxxx xxxx xxxx
572 */
573 DECODE_REJECT (0xfb80d000, 0xf3808000),
574
575 /* Bcc 1111 0xxx xxxx xxxx 10x0 xxxx xxxx xxxx */
576 DECODE_CUSTOM (0xf800d000, 0xf0008000, t32_decode_cond_branch),
577
578 /* BLX 1111 0xxx xxxx xxxx 11x0 xxxx xxxx xxx0 */
579 DECODE_OR (0xf800d001, 0xf000c000),
580 /* B 1111 0xxx xxxx xxxx 10x1 xxxx xxxx xxxx */
581 /* BL 1111 0xxx xxxx xxxx 11x1 xxxx xxxx xxxx */
582 DECODE_SIMULATE (0xf8009000, 0xf0009000, t32_simulate_branch),
583
584 DECODE_END
585};
586
587static const union decode_item t32_table_1111_100x_x0x1__1111[] = {
588 /* Memory hints */
589
590 /* PLD (literal) 1111 1000 x001 1111 1111 xxxx xxxx xxxx */
591 /* PLI (literal) 1111 1001 x001 1111 1111 xxxx xxxx xxxx */
592 DECODE_SIMULATE (0xfe7ff000, 0xf81ff000, kprobe_simulate_nop),
593
594 /* PLD{W} (immediate) 1111 1000 10x1 xxxx 1111 xxxx xxxx xxxx */
595 DECODE_OR (0xffd0f000, 0xf890f000),
596 /* PLD{W} (immediate) 1111 1000 00x1 xxxx 1111 1100 xxxx xxxx */
597 DECODE_OR (0xffd0ff00, 0xf810fc00),
598 /* PLI (immediate) 1111 1001 1001 xxxx 1111 xxxx xxxx xxxx */
599 DECODE_OR (0xfff0f000, 0xf990f000),
600 /* PLI (immediate) 1111 1001 0001 xxxx 1111 1100 xxxx xxxx */
601 DECODE_SIMULATEX(0xfff0ff00, 0xf910fc00, kprobe_simulate_nop,
602 REGS(NOPCX, 0, 0, 0, 0)),
603
604 /* PLD{W} (register) 1111 1000 00x1 xxxx 1111 0000 00xx xxxx */
605 DECODE_OR (0xffd0ffc0, 0xf810f000),
606 /* PLI (register) 1111 1001 0001 xxxx 1111 0000 00xx xxxx */
607 DECODE_SIMULATEX(0xfff0ffc0, 0xf910f000, kprobe_simulate_nop,
608 REGS(NOPCX, 0, 0, 0, NOSPPC)),
609
610 /* Other unallocated instructions... */
611 DECODE_END
612};
613
614static const union decode_item t32_table_1111_100x[] = {
615 /* Store/Load single data item */
616
617 /* ??? 1111 100x x11x xxxx xxxx xxxx xxxx xxxx */
618 DECODE_REJECT (0xfe600000, 0xf8600000),
619
620 /* ??? 1111 1001 0101 xxxx xxxx xxxx xxxx xxxx */
621 DECODE_REJECT (0xfff00000, 0xf9500000),
622
623 /* ??? 1111 100x 0xxx xxxx xxxx 10x0 xxxx xxxx */
624 DECODE_REJECT (0xfe800d00, 0xf8000800),
625
626 /* STRBT 1111 1000 0000 xxxx xxxx 1110 xxxx xxxx */
627 /* STRHT 1111 1000 0010 xxxx xxxx 1110 xxxx xxxx */
628 /* STRT 1111 1000 0100 xxxx xxxx 1110 xxxx xxxx */
629 /* LDRBT 1111 1000 0001 xxxx xxxx 1110 xxxx xxxx */
630 /* LDRSBT 1111 1001 0001 xxxx xxxx 1110 xxxx xxxx */
631 /* LDRHT 1111 1000 0011 xxxx xxxx 1110 xxxx xxxx */
632 /* LDRSHT 1111 1001 0011 xxxx xxxx 1110 xxxx xxxx */
633 /* LDRT 1111 1000 0101 xxxx xxxx 1110 xxxx xxxx */
634 DECODE_REJECT (0xfe800f00, 0xf8000e00),
635
636 /* STR{,B,H} Rn,[PC...] 1111 1000 xxx0 1111 xxxx xxxx xxxx xxxx */
637 DECODE_REJECT (0xff1f0000, 0xf80f0000),
638
639 /* STR{,B,H} PC,[Rn...] 1111 1000 xxx0 xxxx 1111 xxxx xxxx xxxx */
640 DECODE_REJECT (0xff10f000, 0xf800f000),
641
642 /* LDR (literal) 1111 1000 x101 1111 xxxx xxxx xxxx xxxx */
643 DECODE_SIMULATEX(0xff7f0000, 0xf85f0000, t32_simulate_ldr_literal,
644 REGS(PC, ANY, 0, 0, 0)),
645
646 /* STR (immediate) 1111 1000 0100 xxxx xxxx 1xxx xxxx xxxx */
647 /* LDR (immediate) 1111 1000 0101 xxxx xxxx 1xxx xxxx xxxx */
648 DECODE_OR (0xffe00800, 0xf8400800),
649 /* STR (immediate) 1111 1000 1100 xxxx xxxx xxxx xxxx xxxx */
650 /* LDR (immediate) 1111 1000 1101 xxxx xxxx xxxx xxxx xxxx */
651 DECODE_EMULATEX (0xffe00000, 0xf8c00000, t32_emulate_ldrstr,
652 REGS(NOPCX, ANY, 0, 0, 0)),
653
654 /* STR (register) 1111 1000 0100 xxxx xxxx 0000 00xx xxxx */
655 /* LDR (register) 1111 1000 0101 xxxx xxxx 0000 00xx xxxx */
656 DECODE_EMULATEX (0xffe00fc0, 0xf8400000, t32_emulate_ldrstr,
657 REGS(NOPCX, ANY, 0, 0, NOSPPC)),
658
659 /* LDRB (literal) 1111 1000 x001 1111 xxxx xxxx xxxx xxxx */
660 /* LDRSB (literal) 1111 1001 x001 1111 xxxx xxxx xxxx xxxx */
661 /* LDRH (literal) 1111 1000 x011 1111 xxxx xxxx xxxx xxxx */
662 /* LDRSH (literal) 1111 1001 x011 1111 xxxx xxxx xxxx xxxx */
663 DECODE_SIMULATEX(0xfe5f0000, 0xf81f0000, t32_simulate_ldr_literal,
664 REGS(PC, NOSPPCX, 0, 0, 0)),
665
666 /* STRB (immediate) 1111 1000 0000 xxxx xxxx 1xxx xxxx xxxx */
667 /* STRH (immediate) 1111 1000 0010 xxxx xxxx 1xxx xxxx xxxx */
668 /* LDRB (immediate) 1111 1000 0001 xxxx xxxx 1xxx xxxx xxxx */
669 /* LDRSB (immediate) 1111 1001 0001 xxxx xxxx 1xxx xxxx xxxx */
670 /* LDRH (immediate) 1111 1000 0011 xxxx xxxx 1xxx xxxx xxxx */
671 /* LDRSH (immediate) 1111 1001 0011 xxxx xxxx 1xxx xxxx xxxx */
672 DECODE_OR (0xfec00800, 0xf8000800),
673 /* STRB (immediate) 1111 1000 1000 xxxx xxxx xxxx xxxx xxxx */
674 /* STRH (immediate) 1111 1000 1010 xxxx xxxx xxxx xxxx xxxx */
675 /* LDRB (immediate) 1111 1000 1001 xxxx xxxx xxxx xxxx xxxx */
676 /* LDRSB (immediate) 1111 1001 1001 xxxx xxxx xxxx xxxx xxxx */
677 /* LDRH (immediate) 1111 1000 1011 xxxx xxxx xxxx xxxx xxxx */
678 /* LDRSH (immediate) 1111 1001 1011 xxxx xxxx xxxx xxxx xxxx */
679 DECODE_EMULATEX (0xfec00000, 0xf8800000, t32_emulate_ldrstr,
680 REGS(NOPCX, NOSPPCX, 0, 0, 0)),
681
682 /* STRB (register) 1111 1000 0000 xxxx xxxx 0000 00xx xxxx */
683 /* STRH (register) 1111 1000 0010 xxxx xxxx 0000 00xx xxxx */
684 /* LDRB (register) 1111 1000 0001 xxxx xxxx 0000 00xx xxxx */
685 /* LDRSB (register) 1111 1001 0001 xxxx xxxx 0000 00xx xxxx */
686 /* LDRH (register) 1111 1000 0011 xxxx xxxx 0000 00xx xxxx */
687 /* LDRSH (register) 1111 1001 0011 xxxx xxxx 0000 00xx xxxx */
688 DECODE_EMULATEX (0xfe800fc0, 0xf8000000, t32_emulate_ldrstr,
689 REGS(NOPCX, NOSPPCX, 0, 0, NOSPPC)),
690
691 /* Other unallocated instructions... */
692 DECODE_END
693};
694
695static const union decode_item t32_table_1111_1010___1111[] = {
696 /* Data-processing (register) */
697
698 /* ??? 1111 1010 011x xxxx 1111 xxxx 1xxx xxxx */
699 DECODE_REJECT (0xffe0f080, 0xfa60f080),
700
701 /* SXTH 1111 1010 0000 1111 1111 xxxx 1xxx xxxx */
702 /* UXTH 1111 1010 0001 1111 1111 xxxx 1xxx xxxx */
703 /* SXTB16 1111 1010 0010 1111 1111 xxxx 1xxx xxxx */
704 /* UXTB16 1111 1010 0011 1111 1111 xxxx 1xxx xxxx */
705 /* SXTB 1111 1010 0100 1111 1111 xxxx 1xxx xxxx */
706 /* UXTB 1111 1010 0101 1111 1111 xxxx 1xxx xxxx */
707 DECODE_EMULATEX (0xff8ff080, 0xfa0ff080, t32_emulate_rd8rn16rm0_rwflags,
708 REGS(0, 0, NOSPPC, 0, NOSPPC)),
709
710
711 /* ??? 1111 1010 1xxx xxxx 1111 xxxx 0x11 xxxx */
712 DECODE_REJECT (0xff80f0b0, 0xfa80f030),
713 /* ??? 1111 1010 1x11 xxxx 1111 xxxx 0xxx xxxx */
714 DECODE_REJECT (0xffb0f080, 0xfab0f000),
715
716 /* SADD16 1111 1010 1001 xxxx 1111 xxxx 0000 xxxx */
717 /* SASX 1111 1010 1010 xxxx 1111 xxxx 0000 xxxx */
718 /* SSAX 1111 1010 1110 xxxx 1111 xxxx 0000 xxxx */
719 /* SSUB16 1111 1010 1101 xxxx 1111 xxxx 0000 xxxx */
720 /* SADD8 1111 1010 1000 xxxx 1111 xxxx 0000 xxxx */
721 /* SSUB8 1111 1010 1100 xxxx 1111 xxxx 0000 xxxx */
722
723 /* QADD16 1111 1010 1001 xxxx 1111 xxxx 0001 xxxx */
724 /* QASX 1111 1010 1010 xxxx 1111 xxxx 0001 xxxx */
725 /* QSAX 1111 1010 1110 xxxx 1111 xxxx 0001 xxxx */
726 /* QSUB16 1111 1010 1101 xxxx 1111 xxxx 0001 xxxx */
727 /* QADD8 1111 1010 1000 xxxx 1111 xxxx 0001 xxxx */
728 /* QSUB8 1111 1010 1100 xxxx 1111 xxxx 0001 xxxx */
729
730 /* SHADD16 1111 1010 1001 xxxx 1111 xxxx 0010 xxxx */
731 /* SHASX 1111 1010 1010 xxxx 1111 xxxx 0010 xxxx */
732 /* SHSAX 1111 1010 1110 xxxx 1111 xxxx 0010 xxxx */
733 /* SHSUB16 1111 1010 1101 xxxx 1111 xxxx 0010 xxxx */
734 /* SHADD8 1111 1010 1000 xxxx 1111 xxxx 0010 xxxx */
735 /* SHSUB8 1111 1010 1100 xxxx 1111 xxxx 0010 xxxx */
736
737 /* UADD16 1111 1010 1001 xxxx 1111 xxxx 0100 xxxx */
738 /* UASX 1111 1010 1010 xxxx 1111 xxxx 0100 xxxx */
739 /* USAX 1111 1010 1110 xxxx 1111 xxxx 0100 xxxx */
740 /* USUB16 1111 1010 1101 xxxx 1111 xxxx 0100 xxxx */
741 /* UADD8 1111 1010 1000 xxxx 1111 xxxx 0100 xxxx */
742 /* USUB8 1111 1010 1100 xxxx 1111 xxxx 0100 xxxx */
743
744 /* UQADD16 1111 1010 1001 xxxx 1111 xxxx 0101 xxxx */
745 /* UQASX 1111 1010 1010 xxxx 1111 xxxx 0101 xxxx */
746 /* UQSAX 1111 1010 1110 xxxx 1111 xxxx 0101 xxxx */
747 /* UQSUB16 1111 1010 1101 xxxx 1111 xxxx 0101 xxxx */
748 /* UQADD8 1111 1010 1000 xxxx 1111 xxxx 0101 xxxx */
749 /* UQSUB8 1111 1010 1100 xxxx 1111 xxxx 0101 xxxx */
750
751 /* UHADD16 1111 1010 1001 xxxx 1111 xxxx 0110 xxxx */
752 /* UHASX 1111 1010 1010 xxxx 1111 xxxx 0110 xxxx */
753 /* UHSAX 1111 1010 1110 xxxx 1111 xxxx 0110 xxxx */
754 /* UHSUB16 1111 1010 1101 xxxx 1111 xxxx 0110 xxxx */
755 /* UHADD8 1111 1010 1000 xxxx 1111 xxxx 0110 xxxx */
756 /* UHSUB8 1111 1010 1100 xxxx 1111 xxxx 0110 xxxx */
757 DECODE_OR (0xff80f080, 0xfa80f000),
758
759 /* SXTAH 1111 1010 0000 xxxx 1111 xxxx 1xxx xxxx */
760 /* UXTAH 1111 1010 0001 xxxx 1111 xxxx 1xxx xxxx */
761 /* SXTAB16 1111 1010 0010 xxxx 1111 xxxx 1xxx xxxx */
762 /* UXTAB16 1111 1010 0011 xxxx 1111 xxxx 1xxx xxxx */
763 /* SXTAB 1111 1010 0100 xxxx 1111 xxxx 1xxx xxxx */
764 /* UXTAB 1111 1010 0101 xxxx 1111 xxxx 1xxx xxxx */
765 DECODE_OR (0xff80f080, 0xfa00f080),
766
767 /* QADD 1111 1010 1000 xxxx 1111 xxxx 1000 xxxx */
768 /* QDADD 1111 1010 1000 xxxx 1111 xxxx 1001 xxxx */
769 /* QSUB 1111 1010 1000 xxxx 1111 xxxx 1010 xxxx */
770 /* QDSUB 1111 1010 1000 xxxx 1111 xxxx 1011 xxxx */
771 DECODE_OR (0xfff0f0c0, 0xfa80f080),
772
773 /* SEL 1111 1010 1010 xxxx 1111 xxxx 1000 xxxx */
774 DECODE_OR (0xfff0f0f0, 0xfaa0f080),
775
776 /* LSL 1111 1010 000x xxxx 1111 xxxx 0000 xxxx */
777 /* LSR 1111 1010 001x xxxx 1111 xxxx 0000 xxxx */
778 /* ASR 1111 1010 010x xxxx 1111 xxxx 0000 xxxx */
779 /* ROR 1111 1010 011x xxxx 1111 xxxx 0000 xxxx */
780 DECODE_EMULATEX (0xff80f0f0, 0xfa00f000, t32_emulate_rd8rn16rm0_rwflags,
781 REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)),
782
783 /* CLZ 1111 1010 1010 xxxx 1111 xxxx 1000 xxxx */
784 DECODE_OR (0xfff0f0f0, 0xfab0f080),
785
786 /* REV 1111 1010 1001 xxxx 1111 xxxx 1000 xxxx */
787 /* REV16 1111 1010 1001 xxxx 1111 xxxx 1001 xxxx */
788 /* RBIT 1111 1010 1001 xxxx 1111 xxxx 1010 xxxx */
789 /* REVSH 1111 1010 1001 xxxx 1111 xxxx 1011 xxxx */
790 DECODE_EMULATEX (0xfff0f0c0, 0xfa90f080, t32_emulate_rd8rn16_noflags,
791 REGS(NOSPPC, 0, NOSPPC, 0, SAMEAS16)),
792
793 /* Other unallocated instructions... */
794 DECODE_END
795};
796
797static const union decode_item t32_table_1111_1011_0[] = {
798 /* Multiply, multiply accumulate, and absolute difference */
799
800 /* ??? 1111 1011 0000 xxxx 1111 xxxx 0001 xxxx */
801 DECODE_REJECT (0xfff0f0f0, 0xfb00f010),
802 /* ??? 1111 1011 0111 xxxx 1111 xxxx 0001 xxxx */
803 DECODE_REJECT (0xfff0f0f0, 0xfb70f010),
804
805 /* SMULxy 1111 1011 0001 xxxx 1111 xxxx 00xx xxxx */
806 DECODE_OR (0xfff0f0c0, 0xfb10f000),
807 /* MUL 1111 1011 0000 xxxx 1111 xxxx 0000 xxxx */
808 /* SMUAD{X} 1111 1011 0010 xxxx 1111 xxxx 000x xxxx */
809 /* SMULWy 1111 1011 0011 xxxx 1111 xxxx 000x xxxx */
810 /* SMUSD{X} 1111 1011 0100 xxxx 1111 xxxx 000x xxxx */
811 /* SMMUL{R} 1111 1011 0101 xxxx 1111 xxxx 000x xxxx */
812 /* USAD8 1111 1011 0111 xxxx 1111 xxxx 0000 xxxx */
813 DECODE_EMULATEX (0xff80f0e0, 0xfb00f000, t32_emulate_rd8rn16rm0_rwflags,
814 REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)),
815
816 /* ??? 1111 1011 0111 xxxx xxxx xxxx 0001 xxxx */
817 DECODE_REJECT (0xfff000f0, 0xfb700010),
818
819 /* SMLAxy 1111 1011 0001 xxxx xxxx xxxx 00xx xxxx */
820 DECODE_OR (0xfff000c0, 0xfb100000),
821 /* MLA 1111 1011 0000 xxxx xxxx xxxx 0000 xxxx */
822 /* MLS 1111 1011 0000 xxxx xxxx xxxx 0001 xxxx */
823 /* SMLAD{X} 1111 1011 0010 xxxx xxxx xxxx 000x xxxx */
824 /* SMLAWy 1111 1011 0011 xxxx xxxx xxxx 000x xxxx */
825 /* SMLSD{X} 1111 1011 0100 xxxx xxxx xxxx 000x xxxx */
826 /* SMMLA{R} 1111 1011 0101 xxxx xxxx xxxx 000x xxxx */
827 /* SMMLS{R} 1111 1011 0110 xxxx xxxx xxxx 000x xxxx */
828 /* USADA8 1111 1011 0111 xxxx xxxx xxxx 0000 xxxx */
829 DECODE_EMULATEX (0xff8000c0, 0xfb000000, t32_emulate_rd8rn16rm0ra12_noflags,
830 REGS(NOSPPC, NOSPPCX, NOSPPC, 0, NOSPPC)),
831
832 /* Other unallocated instructions... */
833 DECODE_END
834};
835
836static const union decode_item t32_table_1111_1011_1[] = {
837 /* Long multiply, long multiply accumulate, and divide */
838
839 /* UMAAL 1111 1011 1110 xxxx xxxx xxxx 0110 xxxx */
840 DECODE_OR (0xfff000f0, 0xfbe00060),
841 /* SMLALxy 1111 1011 1100 xxxx xxxx xxxx 10xx xxxx */
842 DECODE_OR (0xfff000c0, 0xfbc00080),
843 /* SMLALD{X} 1111 1011 1100 xxxx xxxx xxxx 110x xxxx */
844 /* SMLSLD{X} 1111 1011 1101 xxxx xxxx xxxx 110x xxxx */
845 DECODE_OR (0xffe000e0, 0xfbc000c0),
846 /* SMULL 1111 1011 1000 xxxx xxxx xxxx 0000 xxxx */
847 /* UMULL 1111 1011 1010 xxxx xxxx xxxx 0000 xxxx */
848 /* SMLAL 1111 1011 1100 xxxx xxxx xxxx 0000 xxxx */
849 /* UMLAL 1111 1011 1110 xxxx xxxx xxxx 0000 xxxx */
850 DECODE_EMULATEX (0xff9000f0, 0xfb800000, t32_emulate_rdlo12rdhi8rn16rm0_noflags,
851 REGS(NOSPPC, NOSPPC, NOSPPC, 0, NOSPPC)),
852
853 /* SDIV 1111 1011 1001 xxxx xxxx xxxx 1111 xxxx */
854 /* UDIV 1111 1011 1011 xxxx xxxx xxxx 1111 xxxx */
855 /* Other unallocated instructions... */
856 DECODE_END
857};
858
859const union decode_item kprobe_decode_thumb32_table[] = {
860
861 /*
862 * Load/store multiple instructions
863 * 1110 100x x0xx xxxx xxxx xxxx xxxx xxxx
864 */
865 DECODE_TABLE (0xfe400000, 0xe8000000, t32_table_1110_100x_x0xx),
866
867 /*
868 * Load/store dual, load/store exclusive, table branch
869 * 1110 100x x1xx xxxx xxxx xxxx xxxx xxxx
870 */
871 DECODE_TABLE (0xfe400000, 0xe8400000, t32_table_1110_100x_x1xx),
872
873 /*
874 * Data-processing (shifted register)
875 * 1110 101x xxxx xxxx xxxx xxxx xxxx xxxx
876 */
877 DECODE_TABLE (0xfe000000, 0xea000000, t32_table_1110_101x),
878
879 /*
880 * Coprocessor instructions
881 * 1110 11xx xxxx xxxx xxxx xxxx xxxx xxxx
882 */
883 DECODE_REJECT (0xfc000000, 0xec000000),
884
885 /*
886 * Data-processing (modified immediate)
887 * 1111 0x0x xxxx xxxx 0xxx xxxx xxxx xxxx
888 */
889 DECODE_TABLE (0xfa008000, 0xf0000000, t32_table_1111_0x0x___0),
890
891 /*
892 * Data-processing (plain binary immediate)
893 * 1111 0x1x xxxx xxxx 0xxx xxxx xxxx xxxx
894 */
895 DECODE_TABLE (0xfa008000, 0xf2000000, t32_table_1111_0x1x___0),
896
897 /*
898 * Branches and miscellaneous control
899 * 1111 0xxx xxxx xxxx 1xxx xxxx xxxx xxxx
900 */
901 DECODE_TABLE (0xf8008000, 0xf0008000, t32_table_1111_0xxx___1),
902
903 /*
904 * Advanced SIMD element or structure load/store instructions
905 * 1111 1001 xxx0 xxxx xxxx xxxx xxxx xxxx
906 */
907 DECODE_REJECT (0xff100000, 0xf9000000),
908
909 /*
910 * Memory hints
911 * 1111 100x x0x1 xxxx 1111 xxxx xxxx xxxx
912 */
913 DECODE_TABLE (0xfe50f000, 0xf810f000, t32_table_1111_100x_x0x1__1111),
914
915 /*
916 * Store single data item
917 * 1111 1000 xxx0 xxxx xxxx xxxx xxxx xxxx
918 * Load single data items
919 * 1111 100x xxx1 xxxx xxxx xxxx xxxx xxxx
920 */
921 DECODE_TABLE (0xfe000000, 0xf8000000, t32_table_1111_100x),
922
923 /*
924 * Data-processing (register)
925 * 1111 1010 xxxx xxxx 1111 xxxx xxxx xxxx
926 */
927 DECODE_TABLE (0xff00f000, 0xfa00f000, t32_table_1111_1010___1111),
928
929 /*
930 * Multiply, multiply accumulate, and absolute difference
931 * 1111 1011 0xxx xxxx xxxx xxxx xxxx xxxx
932 */
933 DECODE_TABLE (0xff800000, 0xfb000000, t32_table_1111_1011_0),
934
935 /*
936 * Long multiply, long multiply accumulate, and divide
937 * 1111 1011 1xxx xxxx xxxx xxxx xxxx xxxx
938 */
939 DECODE_TABLE (0xff800000, 0xfb800000, t32_table_1111_1011_1),
940
941 /*
942 * Coprocessor instructions
943 * 1111 11xx xxxx xxxx xxxx xxxx xxxx xxxx
944 */
945 DECODE_END
946};
947#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
948EXPORT_SYMBOL_GPL(kprobe_decode_thumb32_table);
949#endif
950
951static void __kprobes
952t16_simulate_bxblx(struct kprobe *p, struct pt_regs *regs)
953{
954 kprobe_opcode_t insn = p->opcode;
955 unsigned long pc = thumb_probe_pc(p);
956 int rm = (insn >> 3) & 0xf;
957 unsigned long rmv = (rm == 15) ? pc : regs->uregs[rm];
958
959 if (insn & (1 << 7)) /* BLX ? */
960 regs->ARM_lr = (unsigned long)p->addr + 2;
961
962 bx_write_pc(rmv, regs);
963}
964
965static void __kprobes
966t16_simulate_ldr_literal(struct kprobe *p, struct pt_regs *regs)
967{
968 kprobe_opcode_t insn = p->opcode;
969 unsigned long* base = (unsigned long *)(thumb_probe_pc(p) & ~3);
970 long index = insn & 0xff;
971 int rt = (insn >> 8) & 0x7;
972 regs->uregs[rt] = base[index];
973}
974
975static void __kprobes
976t16_simulate_ldrstr_sp_relative(struct kprobe *p, struct pt_regs *regs)
977{
978 kprobe_opcode_t insn = p->opcode;
979 unsigned long* base = (unsigned long *)regs->ARM_sp;
980 long index = insn & 0xff;
981 int rt = (insn >> 8) & 0x7;
982 if (insn & 0x800) /* LDR */
983 regs->uregs[rt] = base[index];
984 else /* STR */
985 base[index] = regs->uregs[rt];
986}
987
988static void __kprobes
989t16_simulate_reladr(struct kprobe *p, struct pt_regs *regs)
990{
991 kprobe_opcode_t insn = p->opcode;
992 unsigned long base = (insn & 0x800) ? regs->ARM_sp
993 : (thumb_probe_pc(p) & ~3);
994 long offset = insn & 0xff;
995 int rt = (insn >> 8) & 0x7;
996 regs->uregs[rt] = base + offset * 4;
997}
998
999static void __kprobes
1000t16_simulate_add_sp_imm(struct kprobe *p, struct pt_regs *regs)
1001{
1002 kprobe_opcode_t insn = p->opcode;
1003 long imm = insn & 0x7f;
1004 if (insn & 0x80) /* SUB */
1005 regs->ARM_sp -= imm * 4;
1006 else /* ADD */
1007 regs->ARM_sp += imm * 4;
1008}
1009
1010static void __kprobes
1011t16_simulate_cbz(struct kprobe *p, struct pt_regs *regs)
1012{
1013 kprobe_opcode_t insn = p->opcode;
1014 int rn = insn & 0x7;
1015 kprobe_opcode_t nonzero = regs->uregs[rn] ? insn : ~insn;
1016 if (nonzero & 0x800) {
1017 long i = insn & 0x200;
1018 long imm5 = insn & 0xf8;
1019 unsigned long pc = thumb_probe_pc(p);
1020 regs->ARM_pc = pc + (i >> 3) + (imm5 >> 2);
1021 }
1022}
1023
1024static void __kprobes
1025t16_simulate_it(struct kprobe *p, struct pt_regs *regs)
1026{
1027 /*
1028 * The 8 IT state bits are split into two parts in CPSR:
1029 * ITSTATE<1:0> are in CPSR<26:25>
1030 * ITSTATE<7:2> are in CPSR<15:10>
1031 * The new IT state is in the lower byte of insn.
1032 */
1033 kprobe_opcode_t insn = p->opcode;
1034 unsigned long cpsr = regs->ARM_cpsr;
1035 cpsr &= ~PSR_IT_MASK;
1036 cpsr |= (insn & 0xfc) << 8;
1037 cpsr |= (insn & 0x03) << 25;
1038 regs->ARM_cpsr = cpsr;
1039}
1040
1041static void __kprobes
1042t16_singlestep_it(struct kprobe *p, struct pt_regs *regs)
1043{
1044 regs->ARM_pc += 2;
1045 t16_simulate_it(p, regs);
1046}
1047
1048static enum kprobe_insn __kprobes
1049t16_decode_it(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1050{
1051 asi->insn_singlestep = t16_singlestep_it;
1052 return INSN_GOOD_NO_SLOT;
1053}
1054
1055static void __kprobes
1056t16_simulate_cond_branch(struct kprobe *p, struct pt_regs *regs)
1057{
1058 kprobe_opcode_t insn = p->opcode;
1059 unsigned long pc = thumb_probe_pc(p);
1060 long offset = insn & 0x7f;
1061 offset -= insn & 0x80; /* Apply sign bit */
1062 regs->ARM_pc = pc + (offset * 2);
1063}
1064
1065static enum kprobe_insn __kprobes
1066t16_decode_cond_branch(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1067{
1068 int cc = (insn >> 8) & 0xf;
1069 asi->insn_check_cc = kprobe_condition_checks[cc];
1070 asi->insn_handler = t16_simulate_cond_branch;
1071 return INSN_GOOD_NO_SLOT;
1072}
1073
1074static void __kprobes
1075t16_simulate_branch(struct kprobe *p, struct pt_regs *regs)
1076{
1077 kprobe_opcode_t insn = p->opcode;
1078 unsigned long pc = thumb_probe_pc(p);
1079 long offset = insn & 0x3ff;
1080 offset -= insn & 0x400; /* Apply sign bit */
1081 regs->ARM_pc = pc + (offset * 2);
1082}
1083
1084static unsigned long __kprobes
1085t16_emulate_loregs(struct kprobe *p, struct pt_regs *regs)
1086{
1087 unsigned long oldcpsr = regs->ARM_cpsr;
1088 unsigned long newcpsr;
1089
1090 __asm__ __volatile__ (
1091 "msr cpsr_fs, %[oldcpsr] \n\t"
1092 "ldmia %[regs], {r0-r7} \n\t"
1093 "blx %[fn] \n\t"
1094 "stmia %[regs], {r0-r7} \n\t"
1095 "mrs %[newcpsr], cpsr \n\t"
1096 : [newcpsr] "=r" (newcpsr)
1097 : [oldcpsr] "r" (oldcpsr), [regs] "r" (regs),
1098 [fn] "r" (p->ainsn.insn_fn)
1099 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
1100 "lr", "memory", "cc"
1101 );
1102
1103 return (oldcpsr & ~APSR_MASK) | (newcpsr & APSR_MASK);
1104}
1105
1106static void __kprobes
1107t16_emulate_loregs_rwflags(struct kprobe *p, struct pt_regs *regs)
1108{
1109 regs->ARM_cpsr = t16_emulate_loregs(p, regs);
1110}
1111
1112static void __kprobes
1113t16_emulate_loregs_noitrwflags(struct kprobe *p, struct pt_regs *regs)
1114{
1115 unsigned long cpsr = t16_emulate_loregs(p, regs);
1116 if (!in_it_block(cpsr))
1117 regs->ARM_cpsr = cpsr;
1118}
1119
1120static void __kprobes
1121t16_emulate_hiregs(struct kprobe *p, struct pt_regs *regs)
1122{
1123 kprobe_opcode_t insn = p->opcode;
1124 unsigned long pc = thumb_probe_pc(p);
1125 int rdn = (insn & 0x7) | ((insn & 0x80) >> 4);
1126 int rm = (insn >> 3) & 0xf;
1127
1128 register unsigned long rdnv asm("r1");
1129 register unsigned long rmv asm("r0");
1130 unsigned long cpsr = regs->ARM_cpsr;
1131
1132 rdnv = (rdn == 15) ? pc : regs->uregs[rdn];
1133 rmv = (rm == 15) ? pc : regs->uregs[rm];
1134
1135 __asm__ __volatile__ (
1136 "msr cpsr_fs, %[cpsr] \n\t"
1137 "blx %[fn] \n\t"
1138 "mrs %[cpsr], cpsr \n\t"
1139 : "=r" (rdnv), [cpsr] "=r" (cpsr)
1140 : "0" (rdnv), "r" (rmv), "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
1141 : "lr", "memory", "cc"
1142 );
1143
1144 if (rdn == 15)
1145 rdnv &= ~1;
1146
1147 regs->uregs[rdn] = rdnv;
1148 regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
1149}
1150
1151static enum kprobe_insn __kprobes
1152t16_decode_hiregs(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1153{
1154 insn &= ~0x00ff;
1155 insn |= 0x001; /* Set Rdn = R1 and Rm = R0 */
1156 ((u16 *)asi->insn)[0] = insn;
1157 asi->insn_handler = t16_emulate_hiregs;
1158 return INSN_GOOD;
1159}
1160
1161static void __kprobes
1162t16_emulate_push(struct kprobe *p, struct pt_regs *regs)
1163{
1164 __asm__ __volatile__ (
1165 "ldr r9, [%[regs], #13*4] \n\t"
1166 "ldr r8, [%[regs], #14*4] \n\t"
1167 "ldmia %[regs], {r0-r7} \n\t"
1168 "blx %[fn] \n\t"
1169 "str r9, [%[regs], #13*4] \n\t"
1170 :
1171 : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn)
1172 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9",
1173 "lr", "memory", "cc"
1174 );
1175}
1176
1177static enum kprobe_insn __kprobes
1178t16_decode_push(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1179{
1180 /*
1181 * To simulate a PUSH we use a Thumb-2 "STMDB R9!, {registers}"
1182 * and call it with R9=SP and LR in the register list represented
1183 * by R8.
1184 */
1185 ((u16 *)asi->insn)[0] = 0xe929; /* 1st half STMDB R9!,{} */
1186 ((u16 *)asi->insn)[1] = insn & 0x1ff; /* 2nd half (register list) */
1187 asi->insn_handler = t16_emulate_push;
1188 return INSN_GOOD;
1189}
1190
1191static void __kprobes
1192t16_emulate_pop_nopc(struct kprobe *p, struct pt_regs *regs)
1193{
1194 __asm__ __volatile__ (
1195 "ldr r9, [%[regs], #13*4] \n\t"
1196 "ldmia %[regs], {r0-r7} \n\t"
1197 "blx %[fn] \n\t"
1198 "stmia %[regs], {r0-r7} \n\t"
1199 "str r9, [%[regs], #13*4] \n\t"
1200 :
1201 : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn)
1202 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
1203 "lr", "memory", "cc"
1204 );
1205}
1206
1207static void __kprobes
1208t16_emulate_pop_pc(struct kprobe *p, struct pt_regs *regs)
1209{
1210 register unsigned long pc asm("r8");
1211
1212 __asm__ __volatile__ (
1213 "ldr r9, [%[regs], #13*4] \n\t"
1214 "ldmia %[regs], {r0-r7} \n\t"
1215 "blx %[fn] \n\t"
1216 "stmia %[regs], {r0-r7} \n\t"
1217 "str r9, [%[regs], #13*4] \n\t"
1218 : "=r" (pc)
1219 : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn)
1220 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
1221 "lr", "memory", "cc"
1222 );
1223
1224 bx_write_pc(pc, regs);
1225}
1226
1227static enum kprobe_insn __kprobes
1228t16_decode_pop(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1229{
1230 /*
1231 * To simulate a POP we use a Thumb-2 "LDMDB R9!, {registers}"
1232 * and call it with R9=SP and PC in the register list represented
1233 * by R8.
1234 */
1235 ((u16 *)asi->insn)[0] = 0xe8b9; /* 1st half LDMIA R9!,{} */
1236 ((u16 *)asi->insn)[1] = insn & 0x1ff; /* 2nd half (register list) */
1237 asi->insn_handler = insn & 0x100 ? t16_emulate_pop_pc
1238 : t16_emulate_pop_nopc;
1239 return INSN_GOOD;
1240}
1241
1242static const union decode_item t16_table_1011[] = {
1243 /* Miscellaneous 16-bit instructions */
1244
1245 /* ADD (SP plus immediate) 1011 0000 0xxx xxxx */
1246 /* SUB (SP minus immediate) 1011 0000 1xxx xxxx */
1247 DECODE_SIMULATE (0xff00, 0xb000, t16_simulate_add_sp_imm),
1248
1249 /* CBZ 1011 00x1 xxxx xxxx */
1250 /* CBNZ 1011 10x1 xxxx xxxx */
1251 DECODE_SIMULATE (0xf500, 0xb100, t16_simulate_cbz),
1252
1253 /* SXTH 1011 0010 00xx xxxx */
1254 /* SXTB 1011 0010 01xx xxxx */
1255 /* UXTH 1011 0010 10xx xxxx */
1256 /* UXTB 1011 0010 11xx xxxx */
1257 /* REV 1011 1010 00xx xxxx */
1258 /* REV16 1011 1010 01xx xxxx */
1259 /* ??? 1011 1010 10xx xxxx */
1260 /* REVSH 1011 1010 11xx xxxx */
1261 DECODE_REJECT (0xffc0, 0xba80),
1262 DECODE_EMULATE (0xf500, 0xb000, t16_emulate_loregs_rwflags),
1263
1264 /* PUSH 1011 010x xxxx xxxx */
1265 DECODE_CUSTOM (0xfe00, 0xb400, t16_decode_push),
1266 /* POP 1011 110x xxxx xxxx */
1267 DECODE_CUSTOM (0xfe00, 0xbc00, t16_decode_pop),
1268
1269 /*
1270 * If-Then, and hints
1271 * 1011 1111 xxxx xxxx
1272 */
1273
1274 /* YIELD 1011 1111 0001 0000 */
1275 DECODE_OR (0xffff, 0xbf10),
1276 /* SEV 1011 1111 0100 0000 */
1277 DECODE_EMULATE (0xffff, 0xbf40, kprobe_emulate_none),
1278 /* NOP 1011 1111 0000 0000 */
1279 /* WFE 1011 1111 0010 0000 */
1280 /* WFI 1011 1111 0011 0000 */
1281 DECODE_SIMULATE (0xffcf, 0xbf00, kprobe_simulate_nop),
1282 /* Unassigned hints 1011 1111 xxxx 0000 */
1283 DECODE_REJECT (0xff0f, 0xbf00),
1284 /* IT 1011 1111 xxxx xxxx */
1285 DECODE_CUSTOM (0xff00, 0xbf00, t16_decode_it),
1286
1287 /* SETEND 1011 0110 010x xxxx */
1288 /* CPS 1011 0110 011x xxxx */
1289 /* BKPT 1011 1110 xxxx xxxx */
1290 /* And unallocated instructions... */
1291 DECODE_END
1292};
1293
1294const union decode_item kprobe_decode_thumb16_table[] = {
1295
1296 /*
1297 * Shift (immediate), add, subtract, move, and compare
1298 * 00xx xxxx xxxx xxxx
1299 */
1300
1301 /* CMP (immediate) 0010 1xxx xxxx xxxx */
1302 DECODE_EMULATE (0xf800, 0x2800, t16_emulate_loregs_rwflags),
1303
1304 /* ADD (register) 0001 100x xxxx xxxx */
1305 /* SUB (register) 0001 101x xxxx xxxx */
1306 /* LSL (immediate) 0000 0xxx xxxx xxxx */
1307 /* LSR (immediate) 0000 1xxx xxxx xxxx */
1308 /* ASR (immediate) 0001 0xxx xxxx xxxx */
1309 /* ADD (immediate, Thumb) 0001 110x xxxx xxxx */
1310 /* SUB (immediate, Thumb) 0001 111x xxxx xxxx */
1311 /* MOV (immediate) 0010 0xxx xxxx xxxx */
1312 /* ADD (immediate, Thumb) 0011 0xxx xxxx xxxx */
1313 /* SUB (immediate, Thumb) 0011 1xxx xxxx xxxx */
1314 DECODE_EMULATE (0xc000, 0x0000, t16_emulate_loregs_noitrwflags),
1315
1316 /*
1317 * 16-bit Thumb data-processing instructions
1318 * 0100 00xx xxxx xxxx
1319 */
1320
1321 /* TST (register) 0100 0010 00xx xxxx */
1322 DECODE_EMULATE (0xffc0, 0x4200, t16_emulate_loregs_rwflags),
1323 /* CMP (register) 0100 0010 10xx xxxx */
1324 /* CMN (register) 0100 0010 11xx xxxx */
1325 DECODE_EMULATE (0xff80, 0x4280, t16_emulate_loregs_rwflags),
1326 /* AND (register) 0100 0000 00xx xxxx */
1327 /* EOR (register) 0100 0000 01xx xxxx */
1328 /* LSL (register) 0100 0000 10xx xxxx */
1329 /* LSR (register) 0100 0000 11xx xxxx */
1330 /* ASR (register) 0100 0001 00xx xxxx */
1331 /* ADC (register) 0100 0001 01xx xxxx */
1332 /* SBC (register) 0100 0001 10xx xxxx */
1333 /* ROR (register) 0100 0001 11xx xxxx */
1334 /* RSB (immediate) 0100 0010 01xx xxxx */
1335 /* ORR (register) 0100 0011 00xx xxxx */
1336 /* MUL 0100 0011 00xx xxxx */
1337 /* BIC (register) 0100 0011 10xx xxxx */
1338 /* MVN (register) 0100 0011 10xx xxxx */
1339 DECODE_EMULATE (0xfc00, 0x4000, t16_emulate_loregs_noitrwflags),
1340
1341 /*
1342 * Special data instructions and branch and exchange
1343 * 0100 01xx xxxx xxxx
1344 */
1345
1346 /* BLX pc 0100 0111 1111 1xxx */
1347 DECODE_REJECT (0xfff8, 0x47f8),
1348
1349 /* BX (register) 0100 0111 0xxx xxxx */
1350 /* BLX (register) 0100 0111 1xxx xxxx */
1351 DECODE_SIMULATE (0xff00, 0x4700, t16_simulate_bxblx),
1352
1353 /* ADD pc, pc 0100 0100 1111 1111 */
1354 DECODE_REJECT (0xffff, 0x44ff),
1355
1356 /* ADD (register) 0100 0100 xxxx xxxx */
1357 /* CMP (register) 0100 0101 xxxx xxxx */
1358 /* MOV (register) 0100 0110 xxxx xxxx */
1359 DECODE_CUSTOM (0xfc00, 0x4400, t16_decode_hiregs),
1360
1361 /*
1362 * Load from Literal Pool
1363 * LDR (literal) 0100 1xxx xxxx xxxx
1364 */
1365 DECODE_SIMULATE (0xf800, 0x4800, t16_simulate_ldr_literal),
1366
1367 /*
1368 * 16-bit Thumb Load/store instructions
1369 * 0101 xxxx xxxx xxxx
1370 * 011x xxxx xxxx xxxx
1371 * 100x xxxx xxxx xxxx
1372 */
1373
1374 /* STR (register) 0101 000x xxxx xxxx */
1375 /* STRH (register) 0101 001x xxxx xxxx */
1376 /* STRB (register) 0101 010x xxxx xxxx */
1377 /* LDRSB (register) 0101 011x xxxx xxxx */
1378 /* LDR (register) 0101 100x xxxx xxxx */
1379 /* LDRH (register) 0101 101x xxxx xxxx */
1380 /* LDRB (register) 0101 110x xxxx xxxx */
1381 /* LDRSH (register) 0101 111x xxxx xxxx */
1382 /* STR (immediate, Thumb) 0110 0xxx xxxx xxxx */
1383 /* LDR (immediate, Thumb) 0110 1xxx xxxx xxxx */
1384 /* STRB (immediate, Thumb) 0111 0xxx xxxx xxxx */
1385 /* LDRB (immediate, Thumb) 0111 1xxx xxxx xxxx */
1386 DECODE_EMULATE (0xc000, 0x4000, t16_emulate_loregs_rwflags),
1387 /* STRH (immediate, Thumb) 1000 0xxx xxxx xxxx */
1388 /* LDRH (immediate, Thumb) 1000 1xxx xxxx xxxx */
1389 DECODE_EMULATE (0xf000, 0x8000, t16_emulate_loregs_rwflags),
1390 /* STR (immediate, Thumb) 1001 0xxx xxxx xxxx */
1391 /* LDR (immediate, Thumb) 1001 1xxx xxxx xxxx */
1392 DECODE_SIMULATE (0xf000, 0x9000, t16_simulate_ldrstr_sp_relative),
1393
1394 /*
1395 * Generate PC-/SP-relative address
1396 * ADR (literal) 1010 0xxx xxxx xxxx
1397 * ADD (SP plus immediate) 1010 1xxx xxxx xxxx
1398 */
1399 DECODE_SIMULATE (0xf000, 0xa000, t16_simulate_reladr),
1400
1401 /*
1402 * Miscellaneous 16-bit instructions
1403 * 1011 xxxx xxxx xxxx
1404 */
1405 DECODE_TABLE (0xf000, 0xb000, t16_table_1011),
1406
1407 /* STM 1100 0xxx xxxx xxxx */
1408 /* LDM 1100 1xxx xxxx xxxx */
1409 DECODE_EMULATE (0xf000, 0xc000, t16_emulate_loregs_rwflags),
1410
1411 /*
1412 * Conditional branch, and Supervisor Call
1413 */
1414
1415 /* Permanently UNDEFINED 1101 1110 xxxx xxxx */
1416 /* SVC 1101 1111 xxxx xxxx */
1417 DECODE_REJECT (0xfe00, 0xde00),
1418
1419 /* Conditional branch 1101 xxxx xxxx xxxx */
1420 DECODE_CUSTOM (0xf000, 0xd000, t16_decode_cond_branch),
1421
1422 /*
1423 * Unconditional branch
1424 * B 1110 0xxx xxxx xxxx
1425 */
1426 DECODE_SIMULATE (0xf800, 0xe000, t16_simulate_branch),
1427
1428 DECODE_END
1429};
1430#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
1431EXPORT_SYMBOL_GPL(kprobe_decode_thumb16_table);
1432#endif
1433
1434static unsigned long __kprobes thumb_check_cc(unsigned long cpsr)
1435{
1436 if (unlikely(in_it_block(cpsr)))
1437 return kprobe_condition_checks[current_cond(cpsr)](cpsr);
1438 return true;
1439}
1440
1441static void __kprobes thumb16_singlestep(struct kprobe *p, struct pt_regs *regs)
1442{
1443 regs->ARM_pc += 2;
1444 p->ainsn.insn_handler(p, regs);
1445 regs->ARM_cpsr = it_advance(regs->ARM_cpsr);
1446}
1447
1448static void __kprobes thumb32_singlestep(struct kprobe *p, struct pt_regs *regs)
1449{
1450 regs->ARM_pc += 4;
1451 p->ainsn.insn_handler(p, regs);
1452 regs->ARM_cpsr = it_advance(regs->ARM_cpsr);
1453}
1454
1455enum kprobe_insn __kprobes
1456thumb16_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1457{
1458 asi->insn_singlestep = thumb16_singlestep;
1459 asi->insn_check_cc = thumb_check_cc;
1460 return kprobe_decode_insn(insn, asi, kprobe_decode_thumb16_table, true);
1461}
1462
1463enum kprobe_insn __kprobes
1464thumb32_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
1465{
1466 asi->insn_singlestep = thumb32_singlestep;
1467 asi->insn_check_cc = thumb_check_cc;
1468 return kprobe_decode_insn(insn, asi, kprobe_decode_thumb32_table, true);
1469}
1/*
2 * arch/arm/kernel/kprobes-thumb.c
3 *
4 * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/types.h>
12#include <linux/kernel.h>
13#include <linux/ptrace.h>
14#include <linux/kprobes.h>
15
16#include "kprobes.h"
17#include "probes-thumb.h"
18
19/* These emulation encodings are functionally equivalent... */
20#define t32_emulate_rd8rn16rm0ra12_noflags \
21 t32_emulate_rdlo12rdhi8rn16rm0_noflags
22
23/* t32 thumb actions */
24
25static void __kprobes
26t32_simulate_table_branch(probes_opcode_t insn,
27 struct arch_probes_insn *asi, struct pt_regs *regs)
28{
29 unsigned long pc = regs->ARM_pc;
30 int rn = (insn >> 16) & 0xf;
31 int rm = insn & 0xf;
32
33 unsigned long rnv = (rn == 15) ? pc : regs->uregs[rn];
34 unsigned long rmv = regs->uregs[rm];
35 unsigned int halfwords;
36
37 if (insn & 0x10) /* TBH */
38 halfwords = ((u16 *)rnv)[rmv];
39 else /* TBB */
40 halfwords = ((u8 *)rnv)[rmv];
41
42 regs->ARM_pc = pc + 2 * halfwords;
43}
44
45static void __kprobes
46t32_simulate_mrs(probes_opcode_t insn,
47 struct arch_probes_insn *asi, struct pt_regs *regs)
48{
49 int rd = (insn >> 8) & 0xf;
50 unsigned long mask = 0xf8ff03df; /* Mask out execution state */
51 regs->uregs[rd] = regs->ARM_cpsr & mask;
52}
53
54static void __kprobes
55t32_simulate_cond_branch(probes_opcode_t insn,
56 struct arch_probes_insn *asi, struct pt_regs *regs)
57{
58 unsigned long pc = regs->ARM_pc;
59
60 long offset = insn & 0x7ff; /* imm11 */
61 offset += (insn & 0x003f0000) >> 5; /* imm6 */
62 offset += (insn & 0x00002000) << 4; /* J1 */
63 offset += (insn & 0x00000800) << 7; /* J2 */
64 offset -= (insn & 0x04000000) >> 7; /* Apply sign bit */
65
66 regs->ARM_pc = pc + (offset * 2);
67}
68
69static enum probes_insn __kprobes
70t32_decode_cond_branch(probes_opcode_t insn, struct arch_probes_insn *asi,
71 const struct decode_header *d)
72{
73 int cc = (insn >> 22) & 0xf;
74 asi->insn_check_cc = probes_condition_checks[cc];
75 asi->insn_handler = t32_simulate_cond_branch;
76 return INSN_GOOD_NO_SLOT;
77}
78
79static void __kprobes
80t32_simulate_branch(probes_opcode_t insn,
81 struct arch_probes_insn *asi, struct pt_regs *regs)
82{
83 unsigned long pc = regs->ARM_pc;
84
85 long offset = insn & 0x7ff; /* imm11 */
86 offset += (insn & 0x03ff0000) >> 5; /* imm10 */
87 offset += (insn & 0x00002000) << 9; /* J1 */
88 offset += (insn & 0x00000800) << 10; /* J2 */
89 if (insn & 0x04000000)
90 offset -= 0x00800000; /* Apply sign bit */
91 else
92 offset ^= 0x00600000; /* Invert J1 and J2 */
93
94 if (insn & (1 << 14)) {
95 /* BL or BLX */
96 regs->ARM_lr = regs->ARM_pc | 1;
97 if (!(insn & (1 << 12))) {
98 /* BLX so switch to ARM mode */
99 regs->ARM_cpsr &= ~PSR_T_BIT;
100 pc &= ~3;
101 }
102 }
103
104 regs->ARM_pc = pc + (offset * 2);
105}
106
107static void __kprobes
108t32_simulate_ldr_literal(probes_opcode_t insn,
109 struct arch_probes_insn *asi, struct pt_regs *regs)
110{
111 unsigned long addr = regs->ARM_pc & ~3;
112 int rt = (insn >> 12) & 0xf;
113 unsigned long rtv;
114
115 long offset = insn & 0xfff;
116 if (insn & 0x00800000)
117 addr += offset;
118 else
119 addr -= offset;
120
121 if (insn & 0x00400000) {
122 /* LDR */
123 rtv = *(unsigned long *)addr;
124 if (rt == 15) {
125 bx_write_pc(rtv, regs);
126 return;
127 }
128 } else if (insn & 0x00200000) {
129 /* LDRH */
130 if (insn & 0x01000000)
131 rtv = *(s16 *)addr;
132 else
133 rtv = *(u16 *)addr;
134 } else {
135 /* LDRB */
136 if (insn & 0x01000000)
137 rtv = *(s8 *)addr;
138 else
139 rtv = *(u8 *)addr;
140 }
141
142 regs->uregs[rt] = rtv;
143}
144
145static enum probes_insn __kprobes
146t32_decode_ldmstm(probes_opcode_t insn, struct arch_probes_insn *asi,
147 const struct decode_header *d)
148{
149 enum probes_insn ret = kprobe_decode_ldmstm(insn, asi, d);
150
151 /* Fixup modified instruction to have halfwords in correct order...*/
152 insn = __mem_to_opcode_arm(asi->insn[0]);
153 ((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(insn >> 16);
154 ((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0xffff);
155
156 return ret;
157}
158
159static void __kprobes
160t32_emulate_ldrdstrd(probes_opcode_t insn,
161 struct arch_probes_insn *asi, struct pt_regs *regs)
162{
163 unsigned long pc = regs->ARM_pc & ~3;
164 int rt1 = (insn >> 12) & 0xf;
165 int rt2 = (insn >> 8) & 0xf;
166 int rn = (insn >> 16) & 0xf;
167
168 register unsigned long rt1v asm("r0") = regs->uregs[rt1];
169 register unsigned long rt2v asm("r1") = regs->uregs[rt2];
170 register unsigned long rnv asm("r2") = (rn == 15) ? pc
171 : regs->uregs[rn];
172
173 __asm__ __volatile__ (
174 "blx %[fn]"
175 : "=r" (rt1v), "=r" (rt2v), "=r" (rnv)
176 : "0" (rt1v), "1" (rt2v), "2" (rnv), [fn] "r" (asi->insn_fn)
177 : "lr", "memory", "cc"
178 );
179
180 if (rn != 15)
181 regs->uregs[rn] = rnv; /* Writeback base register */
182 regs->uregs[rt1] = rt1v;
183 regs->uregs[rt2] = rt2v;
184}
185
186static void __kprobes
187t32_emulate_ldrstr(probes_opcode_t insn,
188 struct arch_probes_insn *asi, struct pt_regs *regs)
189{
190 int rt = (insn >> 12) & 0xf;
191 int rn = (insn >> 16) & 0xf;
192 int rm = insn & 0xf;
193
194 register unsigned long rtv asm("r0") = regs->uregs[rt];
195 register unsigned long rnv asm("r2") = regs->uregs[rn];
196 register unsigned long rmv asm("r3") = regs->uregs[rm];
197
198 __asm__ __volatile__ (
199 "blx %[fn]"
200 : "=r" (rtv), "=r" (rnv)
201 : "0" (rtv), "1" (rnv), "r" (rmv), [fn] "r" (asi->insn_fn)
202 : "lr", "memory", "cc"
203 );
204
205 regs->uregs[rn] = rnv; /* Writeback base register */
206 if (rt == 15) /* Can't be true for a STR as they aren't allowed */
207 bx_write_pc(rtv, regs);
208 else
209 regs->uregs[rt] = rtv;
210}
211
212static void __kprobes
213t32_emulate_rd8rn16rm0_rwflags(probes_opcode_t insn,
214 struct arch_probes_insn *asi, struct pt_regs *regs)
215{
216 int rd = (insn >> 8) & 0xf;
217 int rn = (insn >> 16) & 0xf;
218 int rm = insn & 0xf;
219
220 register unsigned long rdv asm("r1") = regs->uregs[rd];
221 register unsigned long rnv asm("r2") = regs->uregs[rn];
222 register unsigned long rmv asm("r3") = regs->uregs[rm];
223 unsigned long cpsr = regs->ARM_cpsr;
224
225 __asm__ __volatile__ (
226 "msr cpsr_fs, %[cpsr] \n\t"
227 "blx %[fn] \n\t"
228 "mrs %[cpsr], cpsr \n\t"
229 : "=r" (rdv), [cpsr] "=r" (cpsr)
230 : "0" (rdv), "r" (rnv), "r" (rmv),
231 "1" (cpsr), [fn] "r" (asi->insn_fn)
232 : "lr", "memory", "cc"
233 );
234
235 regs->uregs[rd] = rdv;
236 regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
237}
238
239static void __kprobes
240t32_emulate_rd8pc16_noflags(probes_opcode_t insn,
241 struct arch_probes_insn *asi, struct pt_regs *regs)
242{
243 unsigned long pc = regs->ARM_pc;
244 int rd = (insn >> 8) & 0xf;
245
246 register unsigned long rdv asm("r1") = regs->uregs[rd];
247 register unsigned long rnv asm("r2") = pc & ~3;
248
249 __asm__ __volatile__ (
250 "blx %[fn]"
251 : "=r" (rdv)
252 : "0" (rdv), "r" (rnv), [fn] "r" (asi->insn_fn)
253 : "lr", "memory", "cc"
254 );
255
256 regs->uregs[rd] = rdv;
257}
258
259static void __kprobes
260t32_emulate_rd8rn16_noflags(probes_opcode_t insn,
261 struct arch_probes_insn *asi, struct pt_regs *regs)
262{
263 int rd = (insn >> 8) & 0xf;
264 int rn = (insn >> 16) & 0xf;
265
266 register unsigned long rdv asm("r1") = regs->uregs[rd];
267 register unsigned long rnv asm("r2") = regs->uregs[rn];
268
269 __asm__ __volatile__ (
270 "blx %[fn]"
271 : "=r" (rdv)
272 : "0" (rdv), "r" (rnv), [fn] "r" (asi->insn_fn)
273 : "lr", "memory", "cc"
274 );
275
276 regs->uregs[rd] = rdv;
277}
278
279static void __kprobes
280t32_emulate_rdlo12rdhi8rn16rm0_noflags(probes_opcode_t insn,
281 struct arch_probes_insn *asi,
282 struct pt_regs *regs)
283{
284 int rdlo = (insn >> 12) & 0xf;
285 int rdhi = (insn >> 8) & 0xf;
286 int rn = (insn >> 16) & 0xf;
287 int rm = insn & 0xf;
288
289 register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
290 register unsigned long rdhiv asm("r1") = regs->uregs[rdhi];
291 register unsigned long rnv asm("r2") = regs->uregs[rn];
292 register unsigned long rmv asm("r3") = regs->uregs[rm];
293
294 __asm__ __volatile__ (
295 "blx %[fn]"
296 : "=r" (rdlov), "=r" (rdhiv)
297 : "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
298 [fn] "r" (asi->insn_fn)
299 : "lr", "memory", "cc"
300 );
301
302 regs->uregs[rdlo] = rdlov;
303 regs->uregs[rdhi] = rdhiv;
304}
305/* t16 thumb actions */
306
307static void __kprobes
308t16_simulate_bxblx(probes_opcode_t insn,
309 struct arch_probes_insn *asi, struct pt_regs *regs)
310{
311 unsigned long pc = regs->ARM_pc + 2;
312 int rm = (insn >> 3) & 0xf;
313 unsigned long rmv = (rm == 15) ? pc : regs->uregs[rm];
314
315 if (insn & (1 << 7)) /* BLX ? */
316 regs->ARM_lr = regs->ARM_pc | 1;
317
318 bx_write_pc(rmv, regs);
319}
320
321static void __kprobes
322t16_simulate_ldr_literal(probes_opcode_t insn,
323 struct arch_probes_insn *asi, struct pt_regs *regs)
324{
325 unsigned long *base = (unsigned long *)((regs->ARM_pc + 2) & ~3);
326 long index = insn & 0xff;
327 int rt = (insn >> 8) & 0x7;
328 regs->uregs[rt] = base[index];
329}
330
331static void __kprobes
332t16_simulate_ldrstr_sp_relative(probes_opcode_t insn,
333 struct arch_probes_insn *asi, struct pt_regs *regs)
334{
335 unsigned long* base = (unsigned long *)regs->ARM_sp;
336 long index = insn & 0xff;
337 int rt = (insn >> 8) & 0x7;
338 if (insn & 0x800) /* LDR */
339 regs->uregs[rt] = base[index];
340 else /* STR */
341 base[index] = regs->uregs[rt];
342}
343
344static void __kprobes
345t16_simulate_reladr(probes_opcode_t insn,
346 struct arch_probes_insn *asi, struct pt_regs *regs)
347{
348 unsigned long base = (insn & 0x800) ? regs->ARM_sp
349 : ((regs->ARM_pc + 2) & ~3);
350 long offset = insn & 0xff;
351 int rt = (insn >> 8) & 0x7;
352 regs->uregs[rt] = base + offset * 4;
353}
354
355static void __kprobes
356t16_simulate_add_sp_imm(probes_opcode_t insn,
357 struct arch_probes_insn *asi, struct pt_regs *regs)
358{
359 long imm = insn & 0x7f;
360 if (insn & 0x80) /* SUB */
361 regs->ARM_sp -= imm * 4;
362 else /* ADD */
363 regs->ARM_sp += imm * 4;
364}
365
366static void __kprobes
367t16_simulate_cbz(probes_opcode_t insn,
368 struct arch_probes_insn *asi, struct pt_regs *regs)
369{
370 int rn = insn & 0x7;
371 probes_opcode_t nonzero = regs->uregs[rn] ? insn : ~insn;
372 if (nonzero & 0x800) {
373 long i = insn & 0x200;
374 long imm5 = insn & 0xf8;
375 unsigned long pc = regs->ARM_pc + 2;
376 regs->ARM_pc = pc + (i >> 3) + (imm5 >> 2);
377 }
378}
379
380static void __kprobes
381t16_simulate_it(probes_opcode_t insn,
382 struct arch_probes_insn *asi, struct pt_regs *regs)
383{
384 /*
385 * The 8 IT state bits are split into two parts in CPSR:
386 * ITSTATE<1:0> are in CPSR<26:25>
387 * ITSTATE<7:2> are in CPSR<15:10>
388 * The new IT state is in the lower byte of insn.
389 */
390 unsigned long cpsr = regs->ARM_cpsr;
391 cpsr &= ~PSR_IT_MASK;
392 cpsr |= (insn & 0xfc) << 8;
393 cpsr |= (insn & 0x03) << 25;
394 regs->ARM_cpsr = cpsr;
395}
396
397static void __kprobes
398t16_singlestep_it(probes_opcode_t insn,
399 struct arch_probes_insn *asi, struct pt_regs *regs)
400{
401 regs->ARM_pc += 2;
402 t16_simulate_it(insn, asi, regs);
403}
404
405static enum probes_insn __kprobes
406t16_decode_it(probes_opcode_t insn, struct arch_probes_insn *asi,
407 const struct decode_header *d)
408{
409 asi->insn_singlestep = t16_singlestep_it;
410 return INSN_GOOD_NO_SLOT;
411}
412
413static void __kprobes
414t16_simulate_cond_branch(probes_opcode_t insn,
415 struct arch_probes_insn *asi, struct pt_regs *regs)
416{
417 unsigned long pc = regs->ARM_pc + 2;
418 long offset = insn & 0x7f;
419 offset -= insn & 0x80; /* Apply sign bit */
420 regs->ARM_pc = pc + (offset * 2);
421}
422
423static enum probes_insn __kprobes
424t16_decode_cond_branch(probes_opcode_t insn, struct arch_probes_insn *asi,
425 const struct decode_header *d)
426{
427 int cc = (insn >> 8) & 0xf;
428 asi->insn_check_cc = probes_condition_checks[cc];
429 asi->insn_handler = t16_simulate_cond_branch;
430 return INSN_GOOD_NO_SLOT;
431}
432
433static void __kprobes
434t16_simulate_branch(probes_opcode_t insn,
435 struct arch_probes_insn *asi, struct pt_regs *regs)
436{
437 unsigned long pc = regs->ARM_pc + 2;
438 long offset = insn & 0x3ff;
439 offset -= insn & 0x400; /* Apply sign bit */
440 regs->ARM_pc = pc + (offset * 2);
441}
442
443static unsigned long __kprobes
444t16_emulate_loregs(probes_opcode_t insn,
445 struct arch_probes_insn *asi, struct pt_regs *regs)
446{
447 unsigned long oldcpsr = regs->ARM_cpsr;
448 unsigned long newcpsr;
449
450 __asm__ __volatile__ (
451 "msr cpsr_fs, %[oldcpsr] \n\t"
452 "ldmia %[regs], {r0-r7} \n\t"
453 "blx %[fn] \n\t"
454 "stmia %[regs], {r0-r7} \n\t"
455 "mrs %[newcpsr], cpsr \n\t"
456 : [newcpsr] "=r" (newcpsr)
457 : [oldcpsr] "r" (oldcpsr), [regs] "r" (regs),
458 [fn] "r" (asi->insn_fn)
459 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
460 "lr", "memory", "cc"
461 );
462
463 return (oldcpsr & ~APSR_MASK) | (newcpsr & APSR_MASK);
464}
465
466static void __kprobes
467t16_emulate_loregs_rwflags(probes_opcode_t insn,
468 struct arch_probes_insn *asi, struct pt_regs *regs)
469{
470 regs->ARM_cpsr = t16_emulate_loregs(insn, asi, regs);
471}
472
473static void __kprobes
474t16_emulate_loregs_noitrwflags(probes_opcode_t insn,
475 struct arch_probes_insn *asi, struct pt_regs *regs)
476{
477 unsigned long cpsr = t16_emulate_loregs(insn, asi, regs);
478 if (!in_it_block(cpsr))
479 regs->ARM_cpsr = cpsr;
480}
481
482static void __kprobes
483t16_emulate_hiregs(probes_opcode_t insn,
484 struct arch_probes_insn *asi, struct pt_regs *regs)
485{
486 unsigned long pc = regs->ARM_pc + 2;
487 int rdn = (insn & 0x7) | ((insn & 0x80) >> 4);
488 int rm = (insn >> 3) & 0xf;
489
490 register unsigned long rdnv asm("r1");
491 register unsigned long rmv asm("r0");
492 unsigned long cpsr = regs->ARM_cpsr;
493
494 rdnv = (rdn == 15) ? pc : regs->uregs[rdn];
495 rmv = (rm == 15) ? pc : regs->uregs[rm];
496
497 __asm__ __volatile__ (
498 "msr cpsr_fs, %[cpsr] \n\t"
499 "blx %[fn] \n\t"
500 "mrs %[cpsr], cpsr \n\t"
501 : "=r" (rdnv), [cpsr] "=r" (cpsr)
502 : "0" (rdnv), "r" (rmv), "1" (cpsr), [fn] "r" (asi->insn_fn)
503 : "lr", "memory", "cc"
504 );
505
506 if (rdn == 15)
507 rdnv &= ~1;
508
509 regs->uregs[rdn] = rdnv;
510 regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
511}
512
513static enum probes_insn __kprobes
514t16_decode_hiregs(probes_opcode_t insn, struct arch_probes_insn *asi,
515 const struct decode_header *d)
516{
517 insn &= ~0x00ff;
518 insn |= 0x001; /* Set Rdn = R1 and Rm = R0 */
519 ((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(insn);
520 asi->insn_handler = t16_emulate_hiregs;
521 return INSN_GOOD;
522}
523
524static void __kprobes
525t16_emulate_push(probes_opcode_t insn,
526 struct arch_probes_insn *asi, struct pt_regs *regs)
527{
528 __asm__ __volatile__ (
529 "ldr r9, [%[regs], #13*4] \n\t"
530 "ldr r8, [%[regs], #14*4] \n\t"
531 "ldmia %[regs], {r0-r7} \n\t"
532 "blx %[fn] \n\t"
533 "str r9, [%[regs], #13*4] \n\t"
534 :
535 : [regs] "r" (regs), [fn] "r" (asi->insn_fn)
536 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9",
537 "lr", "memory", "cc"
538 );
539}
540
541static enum probes_insn __kprobes
542t16_decode_push(probes_opcode_t insn, struct arch_probes_insn *asi,
543 const struct decode_header *d)
544{
545 /*
546 * To simulate a PUSH we use a Thumb-2 "STMDB R9!, {registers}"
547 * and call it with R9=SP and LR in the register list represented
548 * by R8.
549 */
550 /* 1st half STMDB R9!,{} */
551 ((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(0xe929);
552 /* 2nd half (register list) */
553 ((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0x1ff);
554 asi->insn_handler = t16_emulate_push;
555 return INSN_GOOD;
556}
557
558static void __kprobes
559t16_emulate_pop_nopc(probes_opcode_t insn,
560 struct arch_probes_insn *asi, struct pt_regs *regs)
561{
562 __asm__ __volatile__ (
563 "ldr r9, [%[regs], #13*4] \n\t"
564 "ldmia %[regs], {r0-r7} \n\t"
565 "blx %[fn] \n\t"
566 "stmia %[regs], {r0-r7} \n\t"
567 "str r9, [%[regs], #13*4] \n\t"
568 :
569 : [regs] "r" (regs), [fn] "r" (asi->insn_fn)
570 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
571 "lr", "memory", "cc"
572 );
573}
574
575static void __kprobes
576t16_emulate_pop_pc(probes_opcode_t insn,
577 struct arch_probes_insn *asi, struct pt_regs *regs)
578{
579 register unsigned long pc asm("r8");
580
581 __asm__ __volatile__ (
582 "ldr r9, [%[regs], #13*4] \n\t"
583 "ldmia %[regs], {r0-r7} \n\t"
584 "blx %[fn] \n\t"
585 "stmia %[regs], {r0-r7} \n\t"
586 "str r9, [%[regs], #13*4] \n\t"
587 : "=r" (pc)
588 : [regs] "r" (regs), [fn] "r" (asi->insn_fn)
589 : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
590 "lr", "memory", "cc"
591 );
592
593 bx_write_pc(pc, regs);
594}
595
596static enum probes_insn __kprobes
597t16_decode_pop(probes_opcode_t insn, struct arch_probes_insn *asi,
598 const struct decode_header *d)
599{
600 /*
601 * To simulate a POP we use a Thumb-2 "LDMDB R9!, {registers}"
602 * and call it with R9=SP and PC in the register list represented
603 * by R8.
604 */
605 /* 1st half LDMIA R9!,{} */
606 ((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(0xe8b9);
607 /* 2nd half (register list) */
608 ((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0x1ff);
609 asi->insn_handler = insn & 0x100 ? t16_emulate_pop_pc
610 : t16_emulate_pop_nopc;
611 return INSN_GOOD;
612}
613
614const union decode_action kprobes_t16_actions[NUM_PROBES_T16_ACTIONS] = {
615 [PROBES_T16_ADD_SP] = {.handler = t16_simulate_add_sp_imm},
616 [PROBES_T16_CBZ] = {.handler = t16_simulate_cbz},
617 [PROBES_T16_SIGN_EXTEND] = {.handler = t16_emulate_loregs_rwflags},
618 [PROBES_T16_PUSH] = {.decoder = t16_decode_push},
619 [PROBES_T16_POP] = {.decoder = t16_decode_pop},
620 [PROBES_T16_SEV] = {.handler = probes_emulate_none},
621 [PROBES_T16_WFE] = {.handler = probes_simulate_nop},
622 [PROBES_T16_IT] = {.decoder = t16_decode_it},
623 [PROBES_T16_CMP] = {.handler = t16_emulate_loregs_rwflags},
624 [PROBES_T16_ADDSUB] = {.handler = t16_emulate_loregs_noitrwflags},
625 [PROBES_T16_LOGICAL] = {.handler = t16_emulate_loregs_noitrwflags},
626 [PROBES_T16_LDR_LIT] = {.handler = t16_simulate_ldr_literal},
627 [PROBES_T16_BLX] = {.handler = t16_simulate_bxblx},
628 [PROBES_T16_HIREGOPS] = {.decoder = t16_decode_hiregs},
629 [PROBES_T16_LDRHSTRH] = {.handler = t16_emulate_loregs_rwflags},
630 [PROBES_T16_LDRSTR] = {.handler = t16_simulate_ldrstr_sp_relative},
631 [PROBES_T16_ADR] = {.handler = t16_simulate_reladr},
632 [PROBES_T16_LDMSTM] = {.handler = t16_emulate_loregs_rwflags},
633 [PROBES_T16_BRANCH_COND] = {.decoder = t16_decode_cond_branch},
634 [PROBES_T16_BRANCH] = {.handler = t16_simulate_branch},
635};
636
637const union decode_action kprobes_t32_actions[NUM_PROBES_T32_ACTIONS] = {
638 [PROBES_T32_LDMSTM] = {.decoder = t32_decode_ldmstm},
639 [PROBES_T32_LDRDSTRD] = {.handler = t32_emulate_ldrdstrd},
640 [PROBES_T32_TABLE_BRANCH] = {.handler = t32_simulate_table_branch},
641 [PROBES_T32_TST] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
642 [PROBES_T32_MOV] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
643 [PROBES_T32_ADDSUB] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
644 [PROBES_T32_LOGICAL] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
645 [PROBES_T32_CMP] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
646 [PROBES_T32_ADDWSUBW_PC] = {.handler = t32_emulate_rd8pc16_noflags,},
647 [PROBES_T32_ADDWSUBW] = {.handler = t32_emulate_rd8rn16_noflags},
648 [PROBES_T32_MOVW] = {.handler = t32_emulate_rd8rn16_noflags},
649 [PROBES_T32_SAT] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
650 [PROBES_T32_BITFIELD] = {.handler = t32_emulate_rd8rn16_noflags},
651 [PROBES_T32_SEV] = {.handler = probes_emulate_none},
652 [PROBES_T32_WFE] = {.handler = probes_simulate_nop},
653 [PROBES_T32_MRS] = {.handler = t32_simulate_mrs},
654 [PROBES_T32_BRANCH_COND] = {.decoder = t32_decode_cond_branch},
655 [PROBES_T32_BRANCH] = {.handler = t32_simulate_branch},
656 [PROBES_T32_PLDI] = {.handler = probes_simulate_nop},
657 [PROBES_T32_LDR_LIT] = {.handler = t32_simulate_ldr_literal},
658 [PROBES_T32_LDRSTR] = {.handler = t32_emulate_ldrstr},
659 [PROBES_T32_SIGN_EXTEND] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
660 [PROBES_T32_MEDIA] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
661 [PROBES_T32_REVERSE] = {.handler = t32_emulate_rd8rn16_noflags},
662 [PROBES_T32_MUL_ADD] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
663 [PROBES_T32_MUL_ADD2] = {.handler = t32_emulate_rd8rn16rm0ra12_noflags},
664 [PROBES_T32_MUL_ADD_LONG] = {
665 .handler = t32_emulate_rdlo12rdhi8rn16rm0_noflags},
666};