2 * PowerPC backend to the KGDB stub.
4 * 1998 (c) Michael AK Tesch (tesch@cs.wisc.edu)
5 * Copyright (C) 2003 Timesys Corporation.
6 * Copyright (C) 2004-2006 MontaVista Software, Inc.
7 * PPC64 Mods (C) 2005 Frank Rowand (frowand@mvista.com)
8 * PPC32 support restored by Vitaly Wool <vwool@ru.mvista.com> and
9 * Sergei Shtylyov <sshtylyov@ru.mvista.com>
10 * Copyright (C) 2007-2008 Wind River Systems, Inc.
12 * This file is licensed under the terms of the GNU General Public License
13 * version 2. This program as licensed "as is" without any warranty of any
14 * kind, whether express or implied.
17 #include <linux/kernel.h>
18 #include <linux/init.h>
19 #include <linux/kgdb.h>
20 #include <linux/smp.h>
21 #include <linux/signal.h>
22 #include <linux/ptrace.h>
23 #include <linux/kdebug.h>
24 #include <asm/current.h>
25 #include <asm/processor.h>
26 #include <asm/machdep.h>
29 * This table contains the mapping between PowerPC hardware trap types, and
30 * signals, which are primarily what GDB understands. GDB and the kernel
31 * don't always agree on values, so we use constants taken from gdb-6.2.
33 static struct hard_trap_info
35 unsigned int tt
; /* Trap type code for powerpc */
36 unsigned char signo
; /* Signal that we map this trap into */
37 } hard_trap_info
[] = {
38 { 0x0100, 0x02 /* SIGINT */ }, /* system reset */
39 { 0x0200, 0x0b /* SIGSEGV */ }, /* machine check */
40 { 0x0300, 0x0b /* SIGSEGV */ }, /* data access */
41 { 0x0400, 0x0b /* SIGSEGV */ }, /* instruction access */
42 { 0x0500, 0x02 /* SIGINT */ }, /* external interrupt */
43 { 0x0600, 0x0a /* SIGBUS */ }, /* alignment */
44 { 0x0700, 0x05 /* SIGTRAP */ }, /* program check */
45 { 0x0800, 0x08 /* SIGFPE */ }, /* fp unavailable */
46 { 0x0900, 0x0e /* SIGALRM */ }, /* decrementer */
47 { 0x0c00, 0x14 /* SIGCHLD */ }, /* system call */
48 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
49 { 0x2002, 0x05 /* SIGTRAP */ }, /* debug */
50 #if defined(CONFIG_FSL_BOOKE)
51 { 0x2010, 0x08 /* SIGFPE */ }, /* spe unavailable */
52 { 0x2020, 0x08 /* SIGFPE */ }, /* spe unavailable */
53 { 0x2030, 0x08 /* SIGFPE */ }, /* spe fp data */
54 { 0x2040, 0x08 /* SIGFPE */ }, /* spe fp data */
55 { 0x2050, 0x08 /* SIGFPE */ }, /* spe fp round */
56 { 0x2060, 0x0e /* SIGILL */ }, /* performance monitor */
57 { 0x2900, 0x08 /* SIGFPE */ }, /* apu unavailable */
58 { 0x3100, 0x0e /* SIGALRM */ }, /* fixed interval timer */
59 { 0x3200, 0x02 /* SIGINT */ }, /* watchdog */
60 #else /* ! CONFIG_FSL_BOOKE */
61 { 0x1000, 0x0e /* SIGALRM */ }, /* prog interval timer */
62 { 0x1010, 0x0e /* SIGALRM */ }, /* fixed interval timer */
63 { 0x1020, 0x02 /* SIGINT */ }, /* watchdog */
64 { 0x2010, 0x08 /* SIGFPE */ }, /* fp unavailable */
65 { 0x2020, 0x08 /* SIGFPE */ }, /* ap unavailable */
67 #else /* ! (defined(CONFIG_40x) || defined(CONFIG_BOOKE)) */
68 { 0x0d00, 0x05 /* SIGTRAP */ }, /* single-step */
69 #if defined(CONFIG_8xx)
70 { 0x1000, 0x04 /* SIGILL */ }, /* software emulation */
71 #else /* ! CONFIG_8xx */
72 { 0x0f00, 0x04 /* SIGILL */ }, /* performance monitor */
73 { 0x0f20, 0x08 /* SIGFPE */ }, /* altivec unavailable */
74 { 0x1300, 0x05 /* SIGTRAP */ }, /* instruction address break */
75 #if defined(CONFIG_PPC64)
76 { 0x1200, 0x05 /* SIGILL */ }, /* system error */
77 { 0x1500, 0x04 /* SIGILL */ }, /* soft patch */
78 { 0x1600, 0x04 /* SIGILL */ }, /* maintenance */
79 { 0x1700, 0x08 /* SIGFPE */ }, /* altivec assist */
80 { 0x1800, 0x04 /* SIGILL */ }, /* thermal */
81 #else /* ! CONFIG_PPC64 */
82 { 0x1400, 0x02 /* SIGINT */ }, /* SMI */
83 { 0x1600, 0x08 /* SIGFPE */ }, /* altivec assist */
84 { 0x1700, 0x04 /* SIGILL */ }, /* TAU */
85 { 0x2000, 0x05 /* SIGTRAP */ }, /* run mode */
89 { 0x0000, 0x00 } /* Must be last */
92 static int computeSignal(unsigned int tt
)
94 struct hard_trap_info
*ht
;
96 for (ht
= hard_trap_info
; ht
->tt
&& ht
->signo
; ht
++)
100 return SIGHUP
; /* default for things we don't know about */
103 static int kgdb_call_nmi_hook(struct pt_regs
*regs
)
105 kgdb_nmicallback(raw_smp_processor_id(), regs
);
110 void kgdb_roundup_cpus(unsigned long flags
)
112 smp_send_debugger_break(MSG_ALL_BUT_SELF
);
116 /* KGDB functions to use existing PowerPC64 hooks. */
117 static int kgdb_debugger(struct pt_regs
*regs
)
119 return !kgdb_handle_exception(1, computeSignal(TRAP(regs
)),
123 static int kgdb_handle_breakpoint(struct pt_regs
*regs
)
128 if (kgdb_handle_exception(1, SIGTRAP
, 0, regs
) != 0)
131 if (*(u32
*) (regs
->nip
) == *(u32
*) (&arch_kgdb_ops
.gdb_bpt_instr
))
132 regs
->nip
+= BREAK_INSTR_SIZE
;
137 static int kgdb_singlestep(struct pt_regs
*regs
)
139 struct thread_info
*thread_info
, *exception_thread_info
;
145 * On Book E and perhaps other processsors, singlestep is handled on
146 * the critical exception stack. This causes current_thread_info()
147 * to fail, since it it locates the thread_info by masking off
148 * the low bits of the current stack pointer. We work around
149 * this issue by copying the thread_info from the kernel stack
150 * before calling kgdb_handle_exception, and copying it back
151 * afterwards. On most processors the copy is avoided since
152 * exception_thread_info == thread_info.
154 thread_info
= (struct thread_info
*)(regs
->gpr
[1] & ~(THREAD_SIZE
-1));
155 exception_thread_info
= current_thread_info();
157 if (thread_info
!= exception_thread_info
)
158 memcpy(exception_thread_info
, thread_info
, sizeof *thread_info
);
160 kgdb_handle_exception(0, SIGTRAP
, 0, regs
);
162 if (thread_info
!= exception_thread_info
)
163 memcpy(thread_info
, exception_thread_info
, sizeof *thread_info
);
168 static int kgdb_iabr_match(struct pt_regs
*regs
)
173 if (kgdb_handle_exception(0, computeSignal(TRAP(regs
)), 0, regs
) != 0)
178 static int kgdb_dabr_match(struct pt_regs
*regs
)
183 if (kgdb_handle_exception(0, computeSignal(TRAP(regs
)), 0, regs
) != 0)
188 #define PACK64(ptr, src) do { *(ptr++) = (src); } while (0)
190 #define PACK32(ptr, src) do { \
192 ptr32 = (u32 *)ptr; \
193 *(ptr32++) = (src); \
194 ptr = (unsigned long *)ptr32; \
197 void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs
, struct task_struct
*p
)
199 struct pt_regs
*regs
= (struct pt_regs
*)(p
->thread
.ksp
+
200 STACK_FRAME_OVERHEAD
);
201 unsigned long *ptr
= gdb_regs
;
204 memset(gdb_regs
, 0, NUMREGBYTES
);
207 for (reg
= 0; reg
< 3; reg
++)
208 PACK64(ptr
, regs
->gpr
[reg
]);
210 /* Regs GPR3-13 are caller saved, not in regs->gpr[] */
214 for (reg
= 14; reg
< 32; reg
++)
215 PACK64(ptr
, regs
->gpr
[reg
]);
217 #ifdef CONFIG_FSL_BOOKE
219 for (reg
= 0; reg
< 32; reg
++)
220 PACK64(ptr
, p
->thread
.evr
[reg
]);
225 /* fp registers not used by kernel, leave zero */
226 ptr
+= 32 * 8 / sizeof(long);
229 PACK64(ptr
, regs
->nip
);
230 PACK64(ptr
, regs
->msr
);
231 PACK32(ptr
, regs
->ccr
);
232 PACK64(ptr
, regs
->link
);
233 PACK64(ptr
, regs
->ctr
);
234 PACK32(ptr
, regs
->xer
);
236 BUG_ON((unsigned long)ptr
>
237 (unsigned long)(((void *)gdb_regs
) + NUMREGBYTES
));
240 #define GDB_SIZEOF_REG sizeof(unsigned long)
241 #define GDB_SIZEOF_REG_U32 sizeof(u32)
243 #ifdef CONFIG_FSL_BOOKE
244 #define GDB_SIZEOF_FLOAT_REG sizeof(unsigned long)
246 #define GDB_SIZEOF_FLOAT_REG sizeof(u64)
249 struct dbg_reg_def_t dbg_reg_def
[DBG_MAX_REG_NUM
] =
251 { "r0", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[0]) },
252 { "r1", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[1]) },
253 { "r2", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[2]) },
254 { "r3", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[3]) },
255 { "r4", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[4]) },
256 { "r5", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[5]) },
257 { "r6", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[6]) },
258 { "r7", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[7]) },
259 { "r8", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[8]) },
260 { "r9", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[9]) },
261 { "r10", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[10]) },
262 { "r11", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[11]) },
263 { "r12", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[12]) },
264 { "r13", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[13]) },
265 { "r14", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[14]) },
266 { "r15", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[15]) },
267 { "r16", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[16]) },
268 { "r17", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[17]) },
269 { "r18", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[18]) },
270 { "r19", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[19]) },
271 { "r20", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[20]) },
272 { "r21", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[21]) },
273 { "r22", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[22]) },
274 { "r23", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[23]) },
275 { "r24", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[24]) },
276 { "r25", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[25]) },
277 { "r26", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[26]) },
278 { "r27", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[27]) },
279 { "r28", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[28]) },
280 { "r29", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[29]) },
281 { "r30", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[30]) },
282 { "r31", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, gpr
[31]) },
284 { "f0", GDB_SIZEOF_FLOAT_REG
, 0 },
285 { "f1", GDB_SIZEOF_FLOAT_REG
, 1 },
286 { "f2", GDB_SIZEOF_FLOAT_REG
, 2 },
287 { "f3", GDB_SIZEOF_FLOAT_REG
, 3 },
288 { "f4", GDB_SIZEOF_FLOAT_REG
, 4 },
289 { "f5", GDB_SIZEOF_FLOAT_REG
, 5 },
290 { "f6", GDB_SIZEOF_FLOAT_REG
, 6 },
291 { "f7", GDB_SIZEOF_FLOAT_REG
, 7 },
292 { "f8", GDB_SIZEOF_FLOAT_REG
, 8 },
293 { "f9", GDB_SIZEOF_FLOAT_REG
, 9 },
294 { "f10", GDB_SIZEOF_FLOAT_REG
, 10 },
295 { "f11", GDB_SIZEOF_FLOAT_REG
, 11 },
296 { "f12", GDB_SIZEOF_FLOAT_REG
, 12 },
297 { "f13", GDB_SIZEOF_FLOAT_REG
, 13 },
298 { "f14", GDB_SIZEOF_FLOAT_REG
, 14 },
299 { "f15", GDB_SIZEOF_FLOAT_REG
, 15 },
300 { "f16", GDB_SIZEOF_FLOAT_REG
, 16 },
301 { "f17", GDB_SIZEOF_FLOAT_REG
, 17 },
302 { "f18", GDB_SIZEOF_FLOAT_REG
, 18 },
303 { "f19", GDB_SIZEOF_FLOAT_REG
, 19 },
304 { "f20", GDB_SIZEOF_FLOAT_REG
, 20 },
305 { "f21", GDB_SIZEOF_FLOAT_REG
, 21 },
306 { "f22", GDB_SIZEOF_FLOAT_REG
, 22 },
307 { "f23", GDB_SIZEOF_FLOAT_REG
, 23 },
308 { "f24", GDB_SIZEOF_FLOAT_REG
, 24 },
309 { "f25", GDB_SIZEOF_FLOAT_REG
, 25 },
310 { "f26", GDB_SIZEOF_FLOAT_REG
, 26 },
311 { "f27", GDB_SIZEOF_FLOAT_REG
, 27 },
312 { "f28", GDB_SIZEOF_FLOAT_REG
, 28 },
313 { "f29", GDB_SIZEOF_FLOAT_REG
, 29 },
314 { "f30", GDB_SIZEOF_FLOAT_REG
, 30 },
315 { "f31", GDB_SIZEOF_FLOAT_REG
, 31 },
317 { "pc", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, nip
) },
318 { "msr", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, msr
) },
319 { "cr", GDB_SIZEOF_REG_U32
, offsetof(struct pt_regs
, ccr
) },
320 { "lr", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, link
) },
321 { "ctr", GDB_SIZEOF_REG_U32
, offsetof(struct pt_regs
, ctr
) },
322 { "xer", GDB_SIZEOF_REG
, offsetof(struct pt_regs
, xer
) },
325 char *dbg_get_reg(int regno
, void *mem
, struct pt_regs
*regs
)
327 if (regno
>= DBG_MAX_REG_NUM
|| regno
< 0)
330 if (regno
< 32 || regno
>= 64)
331 /* First 0 -> 31 gpr registers*/
332 /* pc, msr, ls... registers 64 -> 69 */
333 memcpy(mem
, (void *)regs
+ dbg_reg_def
[regno
].offset
,
334 dbg_reg_def
[regno
].size
);
336 if (regno
>= 32 && regno
< 64) {
337 /* FP registers 32 -> 63 */
338 #if defined(CONFIG_FSL_BOOKE) && defined(CONFIG_SPE)
340 memcpy(mem
, current
->thread
.evr
[regno
-32],
341 dbg_reg_def
[regno
].size
);
343 /* fp registers not used by kernel, leave zero */
344 memset(mem
, 0, dbg_reg_def
[regno
].size
);
348 return dbg_reg_def
[regno
].name
;
351 int dbg_set_reg(int regno
, void *mem
, struct pt_regs
*regs
)
353 if (regno
>= DBG_MAX_REG_NUM
|| regno
< 0)
356 if (regno
< 32 || regno
>= 64)
357 /* First 0 -> 31 gpr registers*/
358 /* pc, msr, ls... registers 64 -> 69 */
359 memcpy((void *)regs
+ dbg_reg_def
[regno
].offset
, mem
,
360 dbg_reg_def
[regno
].size
);
362 if (regno
>= 32 && regno
< 64) {
363 /* FP registers 32 -> 63 */
364 #if defined(CONFIG_FSL_BOOKE) && defined(CONFIG_SPE)
365 memcpy(current
->thread
.evr
[regno
-32], mem
,
366 dbg_reg_def
[regno
].size
);
368 /* fp registers not used by kernel, leave zero */
376 void kgdb_arch_set_pc(struct pt_regs
*regs
, unsigned long pc
)
382 * This function does PowerPC specific procesing for interfacing to gdb.
384 int kgdb_arch_handle_exception(int vector
, int signo
, int err_code
,
385 char *remcom_in_buffer
, char *remcom_out_buffer
,
386 struct pt_regs
*linux_regs
)
388 char *ptr
= &remcom_in_buffer
[1];
391 switch (remcom_in_buffer
[0]) {
393 * sAA..AA Step one instruction from AA..AA
394 * This will return an error to gdb ..
398 /* handle the optional parameter */
399 if (kgdb_hex2long(&ptr
, &addr
))
400 linux_regs
->nip
= addr
;
402 atomic_set(&kgdb_cpu_doing_single_step
, -1);
403 /* set the trace bit if we're stepping */
404 if (remcom_in_buffer
[0] == 's') {
405 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
407 mfspr(SPRN_DBCR0
) | DBCR0_IC
| DBCR0_IDM
);
408 linux_regs
->msr
|= MSR_DE
;
410 linux_regs
->msr
|= MSR_SE
;
412 kgdb_single_step
= 1;
413 atomic_set(&kgdb_cpu_doing_single_step
,
414 raw_smp_processor_id());
425 struct kgdb_arch arch_kgdb_ops
= {
426 .gdb_bpt_instr
= {0x7d, 0x82, 0x10, 0x08},
429 static int kgdb_not_implemented(struct pt_regs
*regs
)
434 static void *old__debugger_ipi
;
435 static void *old__debugger
;
436 static void *old__debugger_bpt
;
437 static void *old__debugger_sstep
;
438 static void *old__debugger_iabr_match
;
439 static void *old__debugger_dabr_match
;
440 static void *old__debugger_fault_handler
;
442 int kgdb_arch_init(void)
444 old__debugger_ipi
= __debugger_ipi
;
445 old__debugger
= __debugger
;
446 old__debugger_bpt
= __debugger_bpt
;
447 old__debugger_sstep
= __debugger_sstep
;
448 old__debugger_iabr_match
= __debugger_iabr_match
;
449 old__debugger_dabr_match
= __debugger_dabr_match
;
450 old__debugger_fault_handler
= __debugger_fault_handler
;
452 __debugger_ipi
= kgdb_call_nmi_hook
;
453 __debugger
= kgdb_debugger
;
454 __debugger_bpt
= kgdb_handle_breakpoint
;
455 __debugger_sstep
= kgdb_singlestep
;
456 __debugger_iabr_match
= kgdb_iabr_match
;
457 __debugger_dabr_match
= kgdb_dabr_match
;
458 __debugger_fault_handler
= kgdb_not_implemented
;
463 void kgdb_arch_exit(void)
465 __debugger_ipi
= old__debugger_ipi
;
466 __debugger
= old__debugger
;
467 __debugger_bpt
= old__debugger_bpt
;
468 __debugger_sstep
= old__debugger_sstep
;
469 __debugger_iabr_match
= old__debugger_iabr_match
;
470 __debugger_dabr_match
= old__debugger_dabr_match
;
471 __debugger_fault_handler
= old__debugger_fault_handler
;