1 // SPDX-License-Identifier: GPL-2.0+
2
3 #include <linux/bitops.h>
4 #include <linux/kernel.h>
5 #include <linux/kprobes.h>
6
7 #include "decode-insn.h"
8 #include "simulate-insn.h"
9
csky_insn_reg_get_val(struct pt_regs * regs,unsigned long index,unsigned long * ptr)10 static inline bool csky_insn_reg_get_val(struct pt_regs *regs,
11 unsigned long index,
12 unsigned long *ptr)
13 {
14 if (index < 14)
15 *ptr = *(®s->a0 + index);
16
17 if (index > 15 && index < 31)
18 *ptr = *(®s->exregs[0] + index - 16);
19
20 switch (index) {
21 case 14:
22 *ptr = regs->usp;
23 break;
24 case 15:
25 *ptr = regs->lr;
26 break;
27 case 31:
28 *ptr = regs->tls;
29 break;
30 default:
31 goto fail;
32 }
33
34 return true;
35 fail:
36 return false;
37 }
38
csky_insn_reg_set_val(struct pt_regs * regs,unsigned long index,unsigned long val)39 static inline bool csky_insn_reg_set_val(struct pt_regs *regs,
40 unsigned long index,
41 unsigned long val)
42 {
43 if (index < 14)
44 *(®s->a0 + index) = val;
45
46 if (index > 15 && index < 31)
47 *(®s->exregs[0] + index - 16) = val;
48
49 switch (index) {
50 case 14:
51 regs->usp = val;
52 break;
53 case 15:
54 regs->lr = val;
55 break;
56 case 31:
57 regs->tls = val;
58 break;
59 default:
60 goto fail;
61 }
62
63 return true;
64 fail:
65 return false;
66 }
67
68 void __kprobes
simulate_br16(u32 opcode,long addr,struct pt_regs * regs)69 simulate_br16(u32 opcode, long addr, struct pt_regs *regs)
70 {
71 instruction_pointer_set(regs,
72 addr + sign_extend32((opcode & 0x3ff) << 1, 9));
73 }
74
75 void __kprobes
simulate_br32(u32 opcode,long addr,struct pt_regs * regs)76 simulate_br32(u32 opcode, long addr, struct pt_regs *regs)
77 {
78 instruction_pointer_set(regs,
79 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
80 }
81
82 void __kprobes
simulate_bt16(u32 opcode,long addr,struct pt_regs * regs)83 simulate_bt16(u32 opcode, long addr, struct pt_regs *regs)
84 {
85 if (regs->sr & 1)
86 instruction_pointer_set(regs,
87 addr + sign_extend32((opcode & 0x3ff) << 1, 9));
88 else
89 instruction_pointer_set(regs, addr + 2);
90 }
91
92 void __kprobes
simulate_bt32(u32 opcode,long addr,struct pt_regs * regs)93 simulate_bt32(u32 opcode, long addr, struct pt_regs *regs)
94 {
95 if (regs->sr & 1)
96 instruction_pointer_set(regs,
97 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
98 else
99 instruction_pointer_set(regs, addr + 4);
100 }
101
102 void __kprobes
simulate_bf16(u32 opcode,long addr,struct pt_regs * regs)103 simulate_bf16(u32 opcode, long addr, struct pt_regs *regs)
104 {
105 if (!(regs->sr & 1))
106 instruction_pointer_set(regs,
107 addr + sign_extend32((opcode & 0x3ff) << 1, 9));
108 else
109 instruction_pointer_set(regs, addr + 2);
110 }
111
112 void __kprobes
simulate_bf32(u32 opcode,long addr,struct pt_regs * regs)113 simulate_bf32(u32 opcode, long addr, struct pt_regs *regs)
114 {
115 if (!(regs->sr & 1))
116 instruction_pointer_set(regs,
117 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
118 else
119 instruction_pointer_set(regs, addr + 4);
120 }
121
122 void __kprobes
simulate_jmp16(u32 opcode,long addr,struct pt_regs * regs)123 simulate_jmp16(u32 opcode, long addr, struct pt_regs *regs)
124 {
125 unsigned long tmp = (opcode >> 2) & 0xf;
126
127 csky_insn_reg_get_val(regs, tmp, &tmp);
128
129 instruction_pointer_set(regs, tmp & 0xfffffffe);
130 }
131
132 void __kprobes
simulate_jmp32(u32 opcode,long addr,struct pt_regs * regs)133 simulate_jmp32(u32 opcode, long addr, struct pt_regs *regs)
134 {
135 unsigned long tmp = opcode & 0x1f;
136
137 csky_insn_reg_get_val(regs, tmp, &tmp);
138
139 instruction_pointer_set(regs, tmp & 0xfffffffe);
140 }
141
142 void __kprobes
simulate_jsr16(u32 opcode,long addr,struct pt_regs * regs)143 simulate_jsr16(u32 opcode, long addr, struct pt_regs *regs)
144 {
145 unsigned long tmp = (opcode >> 2) & 0xf;
146
147 csky_insn_reg_get_val(regs, tmp, &tmp);
148
149 regs->lr = addr + 2;
150
151 instruction_pointer_set(regs, tmp & 0xfffffffe);
152 }
153
154 void __kprobes
simulate_jsr32(u32 opcode,long addr,struct pt_regs * regs)155 simulate_jsr32(u32 opcode, long addr, struct pt_regs *regs)
156 {
157 unsigned long tmp = opcode & 0x1f;
158
159 csky_insn_reg_get_val(regs, tmp, &tmp);
160
161 regs->lr = addr + 4;
162
163 instruction_pointer_set(regs, tmp & 0xfffffffe);
164 }
165
166 void __kprobes
simulate_lrw16(u32 opcode,long addr,struct pt_regs * regs)167 simulate_lrw16(u32 opcode, long addr, struct pt_regs *regs)
168 {
169 unsigned long val;
170 unsigned long tmp = (opcode & 0x300) >> 3;
171 unsigned long offset = ((opcode & 0x1f) | tmp) << 2;
172
173 tmp = (opcode & 0xe0) >> 5;
174
175 val = *(unsigned int *)(instruction_pointer(regs) + offset);
176
177 csky_insn_reg_set_val(regs, tmp, val);
178 }
179
180 void __kprobes
simulate_lrw32(u32 opcode,long addr,struct pt_regs * regs)181 simulate_lrw32(u32 opcode, long addr, struct pt_regs *regs)
182 {
183 unsigned long val;
184 unsigned long offset = (opcode & 0xffff0000) >> 14;
185 unsigned long tmp = opcode & 0x0000001f;
186
187 val = *(unsigned int *)
188 ((instruction_pointer(regs) + offset) & 0xfffffffc);
189
190 csky_insn_reg_set_val(regs, tmp, val);
191 }
192
193 void __kprobes
simulate_pop16(u32 opcode,long addr,struct pt_regs * regs)194 simulate_pop16(u32 opcode, long addr, struct pt_regs *regs)
195 {
196 unsigned long *tmp = (unsigned long *)regs->usp;
197 int i;
198
199 for (i = 0; i < (opcode & 0xf); i++) {
200 csky_insn_reg_set_val(regs, i + 4, *tmp);
201 tmp += 1;
202 }
203
204 if (opcode & 0x10) {
205 csky_insn_reg_set_val(regs, 15, *tmp);
206 tmp += 1;
207 }
208
209 regs->usp = (unsigned long)tmp;
210
211 instruction_pointer_set(regs, regs->lr);
212 }
213
214 void __kprobes
simulate_pop32(u32 opcode,long addr,struct pt_regs * regs)215 simulate_pop32(u32 opcode, long addr, struct pt_regs *regs)
216 {
217 unsigned long *tmp = (unsigned long *)regs->usp;
218 int i;
219
220 for (i = 0; i < ((opcode & 0xf0000) >> 16); i++) {
221 csky_insn_reg_set_val(regs, i + 4, *tmp);
222 tmp += 1;
223 }
224
225 if (opcode & 0x100000) {
226 csky_insn_reg_set_val(regs, 15, *tmp);
227 tmp += 1;
228 }
229
230 for (i = 0; i < ((opcode & 0xe00000) >> 21); i++) {
231 csky_insn_reg_set_val(regs, i + 16, *tmp);
232 tmp += 1;
233 }
234
235 if (opcode & 0x1000000) {
236 csky_insn_reg_set_val(regs, 29, *tmp);
237 tmp += 1;
238 }
239
240 regs->usp = (unsigned long)tmp;
241
242 instruction_pointer_set(regs, regs->lr);
243 }
244
245 void __kprobes
simulate_bez32(u32 opcode,long addr,struct pt_regs * regs)246 simulate_bez32(u32 opcode, long addr, struct pt_regs *regs)
247 {
248 unsigned long tmp = opcode & 0x1f;
249
250 csky_insn_reg_get_val(regs, tmp, &tmp);
251
252 if (tmp == 0) {
253 instruction_pointer_set(regs,
254 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
255 } else
256 instruction_pointer_set(regs, addr + 4);
257 }
258
259 void __kprobes
simulate_bnez32(u32 opcode,long addr,struct pt_regs * regs)260 simulate_bnez32(u32 opcode, long addr, struct pt_regs *regs)
261 {
262 unsigned long tmp = opcode & 0x1f;
263
264 csky_insn_reg_get_val(regs, tmp, &tmp);
265
266 if (tmp != 0) {
267 instruction_pointer_set(regs,
268 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
269 } else
270 instruction_pointer_set(regs, addr + 4);
271 }
272
273 void __kprobes
simulate_bnezad32(u32 opcode,long addr,struct pt_regs * regs)274 simulate_bnezad32(u32 opcode, long addr, struct pt_regs *regs)
275 {
276 unsigned long tmp = opcode & 0x1f;
277 long val;
278
279 csky_insn_reg_get_val(regs, tmp, (unsigned long *)&val);
280
281 val -= 1;
282
283 if (val > 0) {
284 instruction_pointer_set(regs,
285 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
286 } else
287 instruction_pointer_set(regs, addr + 4);
288
289 csky_insn_reg_set_val(regs, tmp, (unsigned long)val);
290 }
291
292 void __kprobes
simulate_bhsz32(u32 opcode,long addr,struct pt_regs * regs)293 simulate_bhsz32(u32 opcode, long addr, struct pt_regs *regs)
294 {
295 unsigned long tmp = opcode & 0x1f;
296 unsigned long val;
297
298 csky_insn_reg_get_val(regs, tmp, &val);
299
300 if ((long) val >= 0) {
301 instruction_pointer_set(regs,
302 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
303 } else
304 instruction_pointer_set(regs, addr + 4);
305 }
306
307 void __kprobes
simulate_bhz32(u32 opcode,long addr,struct pt_regs * regs)308 simulate_bhz32(u32 opcode, long addr, struct pt_regs *regs)
309 {
310 unsigned long tmp = opcode & 0x1f;
311 unsigned long val;
312
313 csky_insn_reg_get_val(regs, tmp, &val);
314
315 if ((long) val > 0) {
316 instruction_pointer_set(regs,
317 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
318 } else
319 instruction_pointer_set(regs, addr + 4);
320 }
321
322 void __kprobes
simulate_blsz32(u32 opcode,long addr,struct pt_regs * regs)323 simulate_blsz32(u32 opcode, long addr, struct pt_regs *regs)
324 {
325 unsigned long tmp = opcode & 0x1f;
326 unsigned long val;
327
328 csky_insn_reg_get_val(regs, tmp, &val);
329
330 if ((long) val <= 0) {
331 instruction_pointer_set(regs,
332 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
333 } else
334 instruction_pointer_set(regs, addr + 4);
335 }
336
337 void __kprobes
simulate_blz32(u32 opcode,long addr,struct pt_regs * regs)338 simulate_blz32(u32 opcode, long addr, struct pt_regs *regs)
339 {
340 unsigned long tmp = opcode & 0x1f;
341 unsigned long val;
342
343 csky_insn_reg_get_val(regs, tmp, &val);
344
345 if ((long) val < 0) {
346 instruction_pointer_set(regs,
347 addr + sign_extend32((opcode & 0xffff0000) >> 15, 15));
348 } else
349 instruction_pointer_set(regs, addr + 4);
350 }
351
352 void __kprobes
simulate_bsr32(u32 opcode,long addr,struct pt_regs * regs)353 simulate_bsr32(u32 opcode, long addr, struct pt_regs *regs)
354 {
355 unsigned long tmp;
356
357 tmp = (opcode & 0xffff) << 16;
358 tmp |= (opcode & 0xffff0000) >> 16;
359
360 instruction_pointer_set(regs,
361 addr + sign_extend32((tmp & 0x3ffffff) << 1, 15));
362
363 regs->lr = addr + 4;
364 }
365
366 void __kprobes
simulate_jmpi32(u32 opcode,long addr,struct pt_regs * regs)367 simulate_jmpi32(u32 opcode, long addr, struct pt_regs *regs)
368 {
369 unsigned long val;
370 unsigned long offset = ((opcode & 0xffff0000) >> 14);
371
372 val = *(unsigned int *)
373 ((instruction_pointer(regs) + offset) & 0xfffffffc);
374
375 instruction_pointer_set(regs, val);
376 }
377
378 void __kprobes
simulate_jsri32(u32 opcode,long addr,struct pt_regs * regs)379 simulate_jsri32(u32 opcode, long addr, struct pt_regs *regs)
380 {
381 unsigned long val;
382 unsigned long offset = ((opcode & 0xffff0000) >> 14);
383
384 val = *(unsigned int *)
385 ((instruction_pointer(regs) + offset) & 0xfffffffc);
386
387 regs->lr = addr + 4;
388
389 instruction_pointer_set(regs, val);
390 }
391