4 * Based on arch/arm/kernel/kgdb.c
6 * Copyright (C) 2013 Cavium Inc.
7 * Author: Vijaya Kumar K <vijaya.kumar@caviumnetworks.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include <linux/irq.h>
23 #include <linux/kdebug.h>
24 #include <linux/kgdb.h>
25 #include <asm/traps.h>
27 struct dbg_reg_def_t dbg_reg_def
[DBG_MAX_REG_NUM
] = {
28 { "x0", 8, offsetof(struct pt_regs
, regs
[0])},
29 { "x1", 8, offsetof(struct pt_regs
, regs
[1])},
30 { "x2", 8, offsetof(struct pt_regs
, regs
[2])},
31 { "x3", 8, offsetof(struct pt_regs
, regs
[3])},
32 { "x4", 8, offsetof(struct pt_regs
, regs
[4])},
33 { "x5", 8, offsetof(struct pt_regs
, regs
[5])},
34 { "x6", 8, offsetof(struct pt_regs
, regs
[6])},
35 { "x7", 8, offsetof(struct pt_regs
, regs
[7])},
36 { "x8", 8, offsetof(struct pt_regs
, regs
[8])},
37 { "x9", 8, offsetof(struct pt_regs
, regs
[9])},
38 { "x10", 8, offsetof(struct pt_regs
, regs
[10])},
39 { "x11", 8, offsetof(struct pt_regs
, regs
[11])},
40 { "x12", 8, offsetof(struct pt_regs
, regs
[12])},
41 { "x13", 8, offsetof(struct pt_regs
, regs
[13])},
42 { "x14", 8, offsetof(struct pt_regs
, regs
[14])},
43 { "x15", 8, offsetof(struct pt_regs
, regs
[15])},
44 { "x16", 8, offsetof(struct pt_regs
, regs
[16])},
45 { "x17", 8, offsetof(struct pt_regs
, regs
[17])},
46 { "x18", 8, offsetof(struct pt_regs
, regs
[18])},
47 { "x19", 8, offsetof(struct pt_regs
, regs
[19])},
48 { "x20", 8, offsetof(struct pt_regs
, regs
[20])},
49 { "x21", 8, offsetof(struct pt_regs
, regs
[21])},
50 { "x22", 8, offsetof(struct pt_regs
, regs
[22])},
51 { "x23", 8, offsetof(struct pt_regs
, regs
[23])},
52 { "x24", 8, offsetof(struct pt_regs
, regs
[24])},
53 { "x25", 8, offsetof(struct pt_regs
, regs
[25])},
54 { "x26", 8, offsetof(struct pt_regs
, regs
[26])},
55 { "x27", 8, offsetof(struct pt_regs
, regs
[27])},
56 { "x28", 8, offsetof(struct pt_regs
, regs
[28])},
57 { "x29", 8, offsetof(struct pt_regs
, regs
[29])},
58 { "x30", 8, offsetof(struct pt_regs
, regs
[30])},
59 { "sp", 8, offsetof(struct pt_regs
, sp
)},
60 { "pc", 8, offsetof(struct pt_regs
, pc
)},
61 { "pstate", 8, offsetof(struct pt_regs
, pstate
)},
98 char *dbg_get_reg(int regno
, void *mem
, struct pt_regs
*regs
)
100 if (regno
>= DBG_MAX_REG_NUM
|| regno
< 0)
103 if (dbg_reg_def
[regno
].offset
!= -1)
104 memcpy(mem
, (void *)regs
+ dbg_reg_def
[regno
].offset
,
105 dbg_reg_def
[regno
].size
);
107 memset(mem
, 0, dbg_reg_def
[regno
].size
);
108 return dbg_reg_def
[regno
].name
;
111 int dbg_set_reg(int regno
, void *mem
, struct pt_regs
*regs
)
113 if (regno
>= DBG_MAX_REG_NUM
|| regno
< 0)
116 if (dbg_reg_def
[regno
].offset
!= -1)
117 memcpy((void *)regs
+ dbg_reg_def
[regno
].offset
, mem
,
118 dbg_reg_def
[regno
].size
);
123 sleeping_thread_to_gdb_regs(unsigned long *gdb_regs
, struct task_struct
*task
)
125 struct pt_regs
*thread_regs
;
127 /* Initialize to zero */
128 memset((char *)gdb_regs
, 0, NUMREGBYTES
);
129 thread_regs
= task_pt_regs(task
);
130 memcpy((void *)gdb_regs
, (void *)thread_regs
->regs
, GP_REG_BYTES
);
133 void kgdb_arch_set_pc(struct pt_regs
*regs
, unsigned long pc
)
138 static int compiled_break
;
140 int kgdb_arch_handle_exception(int exception_vector
, int signo
,
141 int err_code
, char *remcom_in_buffer
,
142 char *remcom_out_buffer
,
143 struct pt_regs
*linux_regs
)
149 switch (remcom_in_buffer
[0]) {
153 * Packet D (Detach), k (kill). No special handling
154 * is required here. Handle same as c packet.
158 * Packet c (Continue) to continue executing.
159 * Set pc to required address.
160 * Try to read optional parameter and set pc.
161 * If this was a compiled breakpoint, we need to move
162 * to the next instruction else we will just breakpoint
163 * over and over again.
165 ptr
= &remcom_in_buffer
[1];
166 if (kgdb_hex2long(&ptr
, &addr
))
167 kgdb_arch_set_pc(linux_regs
, addr
);
168 else if (compiled_break
== 1)
169 kgdb_arch_set_pc(linux_regs
, linux_regs
->pc
+ 4);
180 static int kgdb_brk_fn(struct pt_regs
*regs
, unsigned int esr
)
182 kgdb_handle_exception(1, SIGTRAP
, 0, regs
);
186 static int kgdb_compiled_brk_fn(struct pt_regs
*regs
, unsigned int esr
)
189 kgdb_handle_exception(1, SIGTRAP
, 0, regs
);
194 static struct break_hook kgdb_brkpt_hook
= {
195 .esr_mask
= 0xffffffff,
196 .esr_val
= DBG_ESR_VAL_BRK(KGDB_DYN_DGB_BRK_IMM
),
200 static struct break_hook kgdb_compiled_brkpt_hook
= {
201 .esr_mask
= 0xffffffff,
202 .esr_val
= DBG_ESR_VAL_BRK(KDBG_COMPILED_DBG_BRK_IMM
),
203 .fn
= kgdb_compiled_brk_fn
206 static void kgdb_call_nmi_hook(void *ignored
)
208 kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
211 void kgdb_roundup_cpus(unsigned long flags
)
214 smp_call_function(kgdb_call_nmi_hook
, NULL
, 0);
218 static int __kgdb_notify(struct die_args
*args
, unsigned long cmd
)
220 struct pt_regs
*regs
= args
->regs
;
222 if (kgdb_handle_exception(1, args
->signr
, cmd
, regs
))
228 kgdb_notify(struct notifier_block
*self
, unsigned long cmd
, void *ptr
)
233 local_irq_save(flags
);
234 ret
= __kgdb_notify(ptr
, cmd
);
235 local_irq_restore(flags
);
240 static struct notifier_block kgdb_notifier
= {
241 .notifier_call
= kgdb_notify
,
243 * Want to be lowest priority
245 .priority
= -INT_MAX
,
249 * kgdb_arch_init - Perform any architecture specific initalization.
250 * This function will handle the initalization of any architecture
251 * specific callbacks.
253 int kgdb_arch_init(void)
255 int ret
= register_die_notifier(&kgdb_notifier
);
260 register_break_hook(&kgdb_brkpt_hook
);
261 register_break_hook(&kgdb_compiled_brkpt_hook
);
266 * kgdb_arch_exit - Perform any architecture specific uninitalization.
267 * This function will handle the uninitalization of any architecture
268 * specific callbacks, for dynamic registration and unregistration.
270 void kgdb_arch_exit(void)
272 unregister_break_hook(&kgdb_brkpt_hook
);
273 unregister_break_hook(&kgdb_compiled_brkpt_hook
);
274 unregister_die_notifier(&kgdb_notifier
);
278 * ARM instructions are always in LE.
279 * Break instruction is encoded in LE format
281 struct kgdb_arch arch_kgdb_ops
= {
283 KGDB_DYN_BRK_INS_BYTE0
,
284 KGDB_DYN_BRK_INS_BYTE1
,
285 KGDB_DYN_BRK_INS_BYTE2
,
286 KGDB_DYN_BRK_INS_BYTE3
,