1 /*
2 * arch/blackfin/kernel/kgdb.c - Blackfin kgdb pieces
3 *
4 * Copyright 2005-2008 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9 #include <linux/ptrace.h> /* for linux pt_regs struct */
10 #include <linux/kgdb.h>
11 #include <linux/uaccess.h>
12
pt_regs_to_gdb_regs(unsigned long * gdb_regs,struct pt_regs * regs)13 void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
14 {
15 gdb_regs[BFIN_R0] = regs->r0;
16 gdb_regs[BFIN_R1] = regs->r1;
17 gdb_regs[BFIN_R2] = regs->r2;
18 gdb_regs[BFIN_R3] = regs->r3;
19 gdb_regs[BFIN_R4] = regs->r4;
20 gdb_regs[BFIN_R5] = regs->r5;
21 gdb_regs[BFIN_R6] = regs->r6;
22 gdb_regs[BFIN_R7] = regs->r7;
23 gdb_regs[BFIN_P0] = regs->p0;
24 gdb_regs[BFIN_P1] = regs->p1;
25 gdb_regs[BFIN_P2] = regs->p2;
26 gdb_regs[BFIN_P3] = regs->p3;
27 gdb_regs[BFIN_P4] = regs->p4;
28 gdb_regs[BFIN_P5] = regs->p5;
29 gdb_regs[BFIN_SP] = regs->reserved;
30 gdb_regs[BFIN_FP] = regs->fp;
31 gdb_regs[BFIN_I0] = regs->i0;
32 gdb_regs[BFIN_I1] = regs->i1;
33 gdb_regs[BFIN_I2] = regs->i2;
34 gdb_regs[BFIN_I3] = regs->i3;
35 gdb_regs[BFIN_M0] = regs->m0;
36 gdb_regs[BFIN_M1] = regs->m1;
37 gdb_regs[BFIN_M2] = regs->m2;
38 gdb_regs[BFIN_M3] = regs->m3;
39 gdb_regs[BFIN_B0] = regs->b0;
40 gdb_regs[BFIN_B1] = regs->b1;
41 gdb_regs[BFIN_B2] = regs->b2;
42 gdb_regs[BFIN_B3] = regs->b3;
43 gdb_regs[BFIN_L0] = regs->l0;
44 gdb_regs[BFIN_L1] = regs->l1;
45 gdb_regs[BFIN_L2] = regs->l2;
46 gdb_regs[BFIN_L3] = regs->l3;
47 gdb_regs[BFIN_A0_DOT_X] = regs->a0x;
48 gdb_regs[BFIN_A0_DOT_W] = regs->a0w;
49 gdb_regs[BFIN_A1_DOT_X] = regs->a1x;
50 gdb_regs[BFIN_A1_DOT_W] = regs->a1w;
51 gdb_regs[BFIN_ASTAT] = regs->astat;
52 gdb_regs[BFIN_RETS] = regs->rets;
53 gdb_regs[BFIN_LC0] = regs->lc0;
54 gdb_regs[BFIN_LT0] = regs->lt0;
55 gdb_regs[BFIN_LB0] = regs->lb0;
56 gdb_regs[BFIN_LC1] = regs->lc1;
57 gdb_regs[BFIN_LT1] = regs->lt1;
58 gdb_regs[BFIN_LB1] = regs->lb1;
59 gdb_regs[BFIN_CYCLES] = 0;
60 gdb_regs[BFIN_CYCLES2] = 0;
61 gdb_regs[BFIN_USP] = regs->usp;
62 gdb_regs[BFIN_SEQSTAT] = regs->seqstat;
63 gdb_regs[BFIN_SYSCFG] = regs->syscfg;
64 gdb_regs[BFIN_RETI] = regs->pc;
65 gdb_regs[BFIN_RETX] = regs->retx;
66 gdb_regs[BFIN_RETN] = regs->retn;
67 gdb_regs[BFIN_RETE] = regs->rete;
68 gdb_regs[BFIN_PC] = regs->pc;
69 gdb_regs[BFIN_CC] = (regs->astat >> 5) & 1;
70 gdb_regs[BFIN_EXTRA1] = 0;
71 gdb_regs[BFIN_EXTRA2] = 0;
72 gdb_regs[BFIN_EXTRA3] = 0;
73 gdb_regs[BFIN_IPEND] = regs->ipend;
74 }
75
76 /*
77 * Extracts ebp, esp and eip values understandable by gdb from the values
78 * saved by switch_to.
79 * thread.esp points to ebp. flags and ebp are pushed in switch_to hence esp
80 * prior to entering switch_to is 8 greater than the value that is saved.
81 * If switch_to changes, change following code appropriately.
82 */
sleeping_thread_to_gdb_regs(unsigned long * gdb_regs,struct task_struct * p)83 void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
84 {
85 gdb_regs[BFIN_SP] = p->thread.ksp;
86 gdb_regs[BFIN_PC] = p->thread.pc;
87 gdb_regs[BFIN_SEQSTAT] = p->thread.seqstat;
88 }
89
gdb_regs_to_pt_regs(unsigned long * gdb_regs,struct pt_regs * regs)90 void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
91 {
92 regs->r0 = gdb_regs[BFIN_R0];
93 regs->r1 = gdb_regs[BFIN_R1];
94 regs->r2 = gdb_regs[BFIN_R2];
95 regs->r3 = gdb_regs[BFIN_R3];
96 regs->r4 = gdb_regs[BFIN_R4];
97 regs->r5 = gdb_regs[BFIN_R5];
98 regs->r6 = gdb_regs[BFIN_R6];
99 regs->r7 = gdb_regs[BFIN_R7];
100 regs->p0 = gdb_regs[BFIN_P0];
101 regs->p1 = gdb_regs[BFIN_P1];
102 regs->p2 = gdb_regs[BFIN_P2];
103 regs->p3 = gdb_regs[BFIN_P3];
104 regs->p4 = gdb_regs[BFIN_P4];
105 regs->p5 = gdb_regs[BFIN_P5];
106 regs->fp = gdb_regs[BFIN_FP];
107 regs->i0 = gdb_regs[BFIN_I0];
108 regs->i1 = gdb_regs[BFIN_I1];
109 regs->i2 = gdb_regs[BFIN_I2];
110 regs->i3 = gdb_regs[BFIN_I3];
111 regs->m0 = gdb_regs[BFIN_M0];
112 regs->m1 = gdb_regs[BFIN_M1];
113 regs->m2 = gdb_regs[BFIN_M2];
114 regs->m3 = gdb_regs[BFIN_M3];
115 regs->b0 = gdb_regs[BFIN_B0];
116 regs->b1 = gdb_regs[BFIN_B1];
117 regs->b2 = gdb_regs[BFIN_B2];
118 regs->b3 = gdb_regs[BFIN_B3];
119 regs->l0 = gdb_regs[BFIN_L0];
120 regs->l1 = gdb_regs[BFIN_L1];
121 regs->l2 = gdb_regs[BFIN_L2];
122 regs->l3 = gdb_regs[BFIN_L3];
123 regs->a0x = gdb_regs[BFIN_A0_DOT_X];
124 regs->a0w = gdb_regs[BFIN_A0_DOT_W];
125 regs->a1x = gdb_regs[BFIN_A1_DOT_X];
126 regs->a1w = gdb_regs[BFIN_A1_DOT_W];
127 regs->rets = gdb_regs[BFIN_RETS];
128 regs->lc0 = gdb_regs[BFIN_LC0];
129 regs->lt0 = gdb_regs[BFIN_LT0];
130 regs->lb0 = gdb_regs[BFIN_LB0];
131 regs->lc1 = gdb_regs[BFIN_LC1];
132 regs->lt1 = gdb_regs[BFIN_LT1];
133 regs->lb1 = gdb_regs[BFIN_LB1];
134 regs->usp = gdb_regs[BFIN_USP];
135 regs->syscfg = gdb_regs[BFIN_SYSCFG];
136 regs->retx = gdb_regs[BFIN_RETX];
137 regs->retn = gdb_regs[BFIN_RETN];
138 regs->rete = gdb_regs[BFIN_RETE];
139 regs->pc = gdb_regs[BFIN_PC];
140
141 #if 0 /* can't change these */
142 regs->astat = gdb_regs[BFIN_ASTAT];
143 regs->seqstat = gdb_regs[BFIN_SEQSTAT];
144 regs->ipend = gdb_regs[BFIN_IPEND];
145 #endif
146 }
147
148 static struct hw_breakpoint {
149 unsigned int occupied:1;
150 unsigned int skip:1;
151 unsigned int enabled:1;
152 unsigned int type:1;
153 unsigned int dataacc:2;
154 unsigned short count;
155 unsigned int addr;
156 } breakinfo[HW_WATCHPOINT_NUM];
157
bfin_set_hw_break(unsigned long addr,int len,enum kgdb_bptype type)158 static int bfin_set_hw_break(unsigned long addr, int len, enum kgdb_bptype type)
159 {
160 int breakno;
161 int bfin_type;
162 int dataacc = 0;
163
164 switch (type) {
165 case BP_HARDWARE_BREAKPOINT:
166 bfin_type = TYPE_INST_WATCHPOINT;
167 break;
168 case BP_WRITE_WATCHPOINT:
169 dataacc = 1;
170 bfin_type = TYPE_DATA_WATCHPOINT;
171 break;
172 case BP_READ_WATCHPOINT:
173 dataacc = 2;
174 bfin_type = TYPE_DATA_WATCHPOINT;
175 break;
176 case BP_ACCESS_WATCHPOINT:
177 dataacc = 3;
178 bfin_type = TYPE_DATA_WATCHPOINT;
179 break;
180 default:
181 return -ENOSPC;
182 }
183
184 /* Because hardware data watchpoint impelemented in current
185 * Blackfin can not trigger an exception event as the hardware
186 * instrction watchpoint does, we ignaore all data watch point here.
187 * They can be turned on easily after future blackfin design
188 * supports this feature.
189 */
190 for (breakno = 0; breakno < HW_INST_WATCHPOINT_NUM; breakno++)
191 if (bfin_type == breakinfo[breakno].type
192 && !breakinfo[breakno].occupied) {
193 breakinfo[breakno].occupied = 1;
194 breakinfo[breakno].skip = 0;
195 breakinfo[breakno].enabled = 1;
196 breakinfo[breakno].addr = addr;
197 breakinfo[breakno].dataacc = dataacc;
198 breakinfo[breakno].count = 0;
199 return 0;
200 }
201
202 return -ENOSPC;
203 }
204
bfin_remove_hw_break(unsigned long addr,int len,enum kgdb_bptype type)205 static int bfin_remove_hw_break(unsigned long addr, int len, enum kgdb_bptype type)
206 {
207 int breakno;
208 int bfin_type;
209
210 switch (type) {
211 case BP_HARDWARE_BREAKPOINT:
212 bfin_type = TYPE_INST_WATCHPOINT;
213 break;
214 case BP_WRITE_WATCHPOINT:
215 case BP_READ_WATCHPOINT:
216 case BP_ACCESS_WATCHPOINT:
217 bfin_type = TYPE_DATA_WATCHPOINT;
218 break;
219 default:
220 return 0;
221 }
222 for (breakno = 0; breakno < HW_WATCHPOINT_NUM; breakno++)
223 if (bfin_type == breakinfo[breakno].type
224 && breakinfo[breakno].occupied
225 && breakinfo[breakno].addr == addr) {
226 breakinfo[breakno].occupied = 0;
227 breakinfo[breakno].enabled = 0;
228 }
229
230 return 0;
231 }
232
bfin_remove_all_hw_break(void)233 static void bfin_remove_all_hw_break(void)
234 {
235 int breakno;
236
237 memset(breakinfo, 0, sizeof(struct hw_breakpoint)*HW_WATCHPOINT_NUM);
238
239 for (breakno = 0; breakno < HW_INST_WATCHPOINT_NUM; breakno++)
240 breakinfo[breakno].type = TYPE_INST_WATCHPOINT;
241 for (; breakno < HW_WATCHPOINT_NUM; breakno++)
242 breakinfo[breakno].type = TYPE_DATA_WATCHPOINT;
243 }
244
bfin_correct_hw_break(void)245 static void bfin_correct_hw_break(void)
246 {
247 int breakno;
248 unsigned int wpiactl = 0;
249 unsigned int wpdactl = 0;
250 int enable_wp = 0;
251
252 for (breakno = 0; breakno < HW_WATCHPOINT_NUM; breakno++)
253 if (breakinfo[breakno].enabled) {
254 enable_wp = 1;
255
256 switch (breakno) {
257 case 0:
258 wpiactl |= WPIAEN0|WPICNTEN0;
259 bfin_write_WPIA0(breakinfo[breakno].addr);
260 bfin_write_WPIACNT0(breakinfo[breakno].count
261 + breakinfo->skip);
262 break;
263 case 1:
264 wpiactl |= WPIAEN1|WPICNTEN1;
265 bfin_write_WPIA1(breakinfo[breakno].addr);
266 bfin_write_WPIACNT1(breakinfo[breakno].count
267 + breakinfo->skip);
268 break;
269 case 2:
270 wpiactl |= WPIAEN2|WPICNTEN2;
271 bfin_write_WPIA2(breakinfo[breakno].addr);
272 bfin_write_WPIACNT2(breakinfo[breakno].count
273 + breakinfo->skip);
274 break;
275 case 3:
276 wpiactl |= WPIAEN3|WPICNTEN3;
277 bfin_write_WPIA3(breakinfo[breakno].addr);
278 bfin_write_WPIACNT3(breakinfo[breakno].count
279 + breakinfo->skip);
280 break;
281 case 4:
282 wpiactl |= WPIAEN4|WPICNTEN4;
283 bfin_write_WPIA4(breakinfo[breakno].addr);
284 bfin_write_WPIACNT4(breakinfo[breakno].count
285 + breakinfo->skip);
286 break;
287 case 5:
288 wpiactl |= WPIAEN5|WPICNTEN5;
289 bfin_write_WPIA5(breakinfo[breakno].addr);
290 bfin_write_WPIACNT5(breakinfo[breakno].count
291 + breakinfo->skip);
292 break;
293 case 6:
294 wpdactl |= WPDAEN0|WPDCNTEN0|WPDSRC0;
295 wpdactl |= breakinfo[breakno].dataacc
296 << WPDACC0_OFFSET;
297 bfin_write_WPDA0(breakinfo[breakno].addr);
298 bfin_write_WPDACNT0(breakinfo[breakno].count
299 + breakinfo->skip);
300 break;
301 case 7:
302 wpdactl |= WPDAEN1|WPDCNTEN1|WPDSRC1;
303 wpdactl |= breakinfo[breakno].dataacc
304 << WPDACC1_OFFSET;
305 bfin_write_WPDA1(breakinfo[breakno].addr);
306 bfin_write_WPDACNT1(breakinfo[breakno].count
307 + breakinfo->skip);
308 break;
309 }
310 }
311
312 /* Should enable WPPWR bit first before set any other
313 * WPIACTL and WPDACTL bits */
314 if (enable_wp) {
315 bfin_write_WPIACTL(WPPWR);
316 CSYNC();
317 bfin_write_WPIACTL(wpiactl|WPPWR);
318 bfin_write_WPDACTL(wpdactl);
319 CSYNC();
320 }
321 }
322
bfin_disable_hw_debug(struct pt_regs * regs)323 static void bfin_disable_hw_debug(struct pt_regs *regs)
324 {
325 /* Disable hardware debugging while we are in kgdb */
326 bfin_write_WPIACTL(0);
327 bfin_write_WPDACTL(0);
328 CSYNC();
329 }
330
331 #ifdef CONFIG_SMP
kgdb_passive_cpu_callback(void * info)332 void kgdb_passive_cpu_callback(void *info)
333 {
334 kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
335 }
336
kgdb_roundup_cpus(unsigned long flags)337 void kgdb_roundup_cpus(unsigned long flags)
338 {
339 smp_call_function(kgdb_passive_cpu_callback, NULL, 0);
340 }
341
kgdb_roundup_cpu(int cpu,unsigned long flags)342 void kgdb_roundup_cpu(int cpu, unsigned long flags)
343 {
344 smp_call_function_single(cpu, kgdb_passive_cpu_callback, NULL, 0);
345 }
346 #endif
347
348 #ifdef CONFIG_IPIPE
349 static unsigned long kgdb_arch_imask;
350 #endif
351
kgdb_post_primary_code(struct pt_regs * regs,int e_vector,int err_code)352 void kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
353 {
354 if (kgdb_single_step)
355 preempt_enable();
356
357 #ifdef CONFIG_IPIPE
358 if (kgdb_arch_imask) {
359 cpu_pda[raw_smp_processor_id()].ex_imask = kgdb_arch_imask;
360 kgdb_arch_imask = 0;
361 }
362 #endif
363 }
364
kgdb_arch_handle_exception(int vector,int signo,int err_code,char * remcom_in_buffer,char * remcom_out_buffer,struct pt_regs * regs)365 int kgdb_arch_handle_exception(int vector, int signo,
366 int err_code, char *remcom_in_buffer,
367 char *remcom_out_buffer,
368 struct pt_regs *regs)
369 {
370 long addr;
371 char *ptr;
372 int newPC;
373 int i;
374
375 switch (remcom_in_buffer[0]) {
376 case 'c':
377 case 's':
378 if (kgdb_contthread && kgdb_contthread != current) {
379 strcpy(remcom_out_buffer, "E00");
380 break;
381 }
382
383 kgdb_contthread = NULL;
384
385 /* try to read optional parameter, pc unchanged if no parm */
386 ptr = &remcom_in_buffer[1];
387 if (kgdb_hex2long(&ptr, &addr)) {
388 regs->retx = addr;
389 }
390 newPC = regs->retx;
391
392 /* clear the trace bit */
393 regs->syscfg &= 0xfffffffe;
394
395 /* set the trace bit if we're stepping */
396 if (remcom_in_buffer[0] == 's') {
397 regs->syscfg |= 0x1;
398 kgdb_single_step = regs->ipend;
399 kgdb_single_step >>= 6;
400 for (i = 10; i > 0; i--, kgdb_single_step >>= 1)
401 if (kgdb_single_step & 1)
402 break;
403 /* i indicate event priority of current stopped instruction
404 * user space instruction is 0, IVG15 is 1, IVTMR is 10.
405 * kgdb_single_step > 0 means in single step mode
406 */
407 kgdb_single_step = i + 1;
408
409 preempt_disable();
410 #ifdef CONFIG_IPIPE
411 kgdb_arch_imask = cpu_pda[raw_smp_processor_id()].ex_imask;
412 cpu_pda[raw_smp_processor_id()].ex_imask = 0;
413 #endif
414 }
415
416 bfin_correct_hw_break();
417
418 return 0;
419 } /* switch */
420 return -1; /* this means that we do not want to exit from the handler */
421 }
422
423 struct kgdb_arch arch_kgdb_ops = {
424 .gdb_bpt_instr = {0xa1},
425 .flags = KGDB_HW_BREAKPOINT,
426 .set_hw_breakpoint = bfin_set_hw_break,
427 .remove_hw_breakpoint = bfin_remove_hw_break,
428 .disable_hw_break = bfin_disable_hw_debug,
429 .remove_all_hw_break = bfin_remove_all_hw_break,
430 .correct_hw_break = bfin_correct_hw_break,
431 };
432
433 #define IN_MEM(addr, size, l1_addr, l1_size) \
434 ({ \
435 unsigned long __addr = (unsigned long)(addr); \
436 (l1_size && __addr >= l1_addr && __addr + (size) <= l1_addr + l1_size); \
437 })
438 #define ASYNC_BANK_SIZE \
439 (ASYNC_BANK0_SIZE + ASYNC_BANK1_SIZE + \
440 ASYNC_BANK2_SIZE + ASYNC_BANK3_SIZE)
441
kgdb_validate_break_address(unsigned long addr)442 int kgdb_validate_break_address(unsigned long addr)
443 {
444 int cpu = raw_smp_processor_id();
445
446 if (addr >= 0x1000 && (addr + BREAK_INSTR_SIZE) <= physical_mem_end)
447 return 0;
448 if (IN_MEM(addr, BREAK_INSTR_SIZE, ASYNC_BANK0_BASE, ASYNC_BANK_SIZE))
449 return 0;
450 if (cpu == 0 && IN_MEM(addr, BREAK_INSTR_SIZE, L1_CODE_START, L1_CODE_LENGTH))
451 return 0;
452 #ifdef CONFIG_SMP
453 else if (cpu == 1 && IN_MEM(addr, BREAK_INSTR_SIZE, COREB_L1_CODE_START, L1_CODE_LENGTH))
454 return 0;
455 #endif
456 if (IN_MEM(addr, BREAK_INSTR_SIZE, L2_START, L2_LENGTH))
457 return 0;
458
459 return -EFAULT;
460 }
461
kgdb_arch_set_pc(struct pt_regs * regs,unsigned long ip)462 void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
463 {
464 regs->retx = ip;
465 }
466
kgdb_arch_init(void)467 int kgdb_arch_init(void)
468 {
469 kgdb_single_step = 0;
470 #ifdef CONFIG_IPIPE
471 kgdb_arch_imask = 0;
472 #endif
473
474 bfin_remove_all_hw_break();
475 return 0;
476 }
477
kgdb_arch_exit(void)478 void kgdb_arch_exit(void)
479 {
480 }
481