1 // SPDX-License-Identifier: GPL-2.0-only 1
2 /*
3 * arch/hexagon/kernel/kgdb.c - Hexagon KGDB S
4 *
5 * Copyright (c) 2011-2012, The Linux Foundati
6 */
7
8 #include <linux/irq.h>
9 #include <linux/sched.h>
10 #include <linux/sched/task_stack.h>
11 #include <linux/kdebug.h>
12 #include <linux/kgdb.h>
13
14 /* All registers are 4 bytes, for now */
15 #define GDB_SIZEOF_REG 4
16
17 /* The register names are used during printing
18 * Keep these at three letters to pretty-print
19 struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_N
20 { " r0", GDB_SIZEOF_REG, offsetof(stru
21 { " r1", GDB_SIZEOF_REG, offsetof(stru
22 { " r2", GDB_SIZEOF_REG, offsetof(stru
23 { " r3", GDB_SIZEOF_REG, offsetof(stru
24 { " r4", GDB_SIZEOF_REG, offsetof(stru
25 { " r5", GDB_SIZEOF_REG, offsetof(stru
26 { " r6", GDB_SIZEOF_REG, offsetof(stru
27 { " r7", GDB_SIZEOF_REG, offsetof(stru
28 { " r8", GDB_SIZEOF_REG, offsetof(stru
29 { " r9", GDB_SIZEOF_REG, offsetof(stru
30 { "r10", GDB_SIZEOF_REG, offsetof(stru
31 { "r11", GDB_SIZEOF_REG, offsetof(stru
32 { "r12", GDB_SIZEOF_REG, offsetof(stru
33 { "r13", GDB_SIZEOF_REG, offsetof(stru
34 { "r14", GDB_SIZEOF_REG, offsetof(stru
35 { "r15", GDB_SIZEOF_REG, offsetof(stru
36 { "r16", GDB_SIZEOF_REG, offsetof(stru
37 { "r17", GDB_SIZEOF_REG, offsetof(stru
38 { "r18", GDB_SIZEOF_REG, offsetof(stru
39 { "r19", GDB_SIZEOF_REG, offsetof(stru
40 { "r20", GDB_SIZEOF_REG, offsetof(stru
41 { "r21", GDB_SIZEOF_REG, offsetof(stru
42 { "r22", GDB_SIZEOF_REG, offsetof(stru
43 { "r23", GDB_SIZEOF_REG, offsetof(stru
44 { "r24", GDB_SIZEOF_REG, offsetof(stru
45 { "r25", GDB_SIZEOF_REG, offsetof(stru
46 { "r26", GDB_SIZEOF_REG, offsetof(stru
47 { "r27", GDB_SIZEOF_REG, offsetof(stru
48 { "r28", GDB_SIZEOF_REG, offsetof(stru
49 { "r29", GDB_SIZEOF_REG, offsetof(stru
50 { "r30", GDB_SIZEOF_REG, offsetof(stru
51 { "r31", GDB_SIZEOF_REG, offsetof(stru
52
53 { "usr", GDB_SIZEOF_REG, offsetof(stru
54 { "preds", GDB_SIZEOF_REG, offsetof(st
55 { " m0", GDB_SIZEOF_REG, offsetof(stru
56 { " m1", GDB_SIZEOF_REG, offsetof(stru
57 { "sa0", GDB_SIZEOF_REG, offsetof(stru
58 { "sa1", GDB_SIZEOF_REG, offsetof(stru
59 { "lc0", GDB_SIZEOF_REG, offsetof(stru
60 { "lc1", GDB_SIZEOF_REG, offsetof(stru
61 { " gp", GDB_SIZEOF_REG, offsetof(stru
62 { "ugp", GDB_SIZEOF_REG, offsetof(stru
63 { "cs0", GDB_SIZEOF_REG, offsetof(stru
64 { "cs1", GDB_SIZEOF_REG, offsetof(stru
65 { "psp", GDB_SIZEOF_REG, offsetof(stru
66 { "elr", GDB_SIZEOF_REG, offsetof(stru
67 { "est", GDB_SIZEOF_REG, offsetof(stru
68 { "badva", GDB_SIZEOF_REG, offsetof(st
69 { "restart_r0", GDB_SIZEOF_REG, offset
70 { "syscall_nr", GDB_SIZEOF_REG, offset
71 };
72
73 const struct kgdb_arch arch_kgdb_ops = {
74 /* trap0(#0xDB) 0x0cdb0054 */
75 .gdb_bpt_instr = {0x54, 0x00, 0xdb, 0x
76 };
77
78 char *dbg_get_reg(int regno, void *mem, struct
79 {
80 if (regno >= DBG_MAX_REG_NUM || regno
81 return NULL;
82
83 *((unsigned long *) mem) = *((unsigned
84 dbg_reg_def[regno].offset));
85
86 return dbg_reg_def[regno].name;
87 }
88
89 int dbg_set_reg(int regno, void *mem, struct p
90 {
91 if (regno >= DBG_MAX_REG_NUM || regno
92 return -EINVAL;
93
94 *((unsigned long *) ((void *)regs + db
95 *((unsigned long *) mem);
96
97 return 0;
98 }
99
100 void kgdb_arch_set_pc(struct pt_regs *regs, un
101 {
102 instruction_pointer(regs) = pc;
103 }
104
105
106 /* Not yet working */
107 void sleeping_thread_to_gdb_regs(unsigned long
108 struct task_s
109 {
110 struct pt_regs *thread_regs;
111
112 if (task == NULL)
113 return;
114
115 /* Initialize to zero */
116 memset(gdb_regs, 0, NUMREGBYTES);
117
118 /* Otherwise, we have only some regist
119 thread_regs = task_pt_regs(task);
120 gdb_regs[0] = thread_regs->r00;
121 }
122
123 /**
124 * kgdb_arch_handle_exception - Handle archite
125 * @vector: The error vector of the exception
126 * @signo: The signal number of the exception
127 * @err_code: The error code of the exception
128 * @remcom_in_buffer: The buffer of the packet
129 * @remcom_out_buffer: The buffer of %BUFMAX b
130 * @regs: The &struct pt_regs of the current p
131 *
132 * This function MUST handle the 'c' and 's' c
133 * as well packets to set / remove a hardware
134 * If there are additional packets which the h
135 * they are handled here. The code should ret
136 * process more packets, and a %0 or %1 if it
137 * kgdb callback.
138 *
139 * Not yet working.
140 */
141 int kgdb_arch_handle_exception(int vector, int
142 char *remcom_in
143 struct pt_regs
144 {
145 switch (remcom_in_buffer[0]) {
146 case 's':
147 case 'c':
148 return 0;
149 }
150 /* Stay in the debugger. */
151 return -1;
152 }
153
154 static int __kgdb_notify(struct die_args *args
155 {
156 /* cpu roundup */
157 if (atomic_read(&kgdb_active) != -1) {
158 kgdb_nmicallback(smp_processor
159 return NOTIFY_STOP;
160 }
161
162 if (user_mode(args->regs))
163 return NOTIFY_DONE;
164
165 if (kgdb_handle_exception(args->trapnr
166 args->regs
167 return NOTIFY_DONE;
168
169 return NOTIFY_STOP;
170 }
171
172 static int
173 kgdb_notify(struct notifier_block *self, unsig
174 {
175 unsigned long flags;
176 int ret;
177
178 local_irq_save(flags);
179 ret = __kgdb_notify(ptr, cmd);
180 local_irq_restore(flags);
181
182 return ret;
183 }
184
185 static struct notifier_block kgdb_notifier = {
186 .notifier_call = kgdb_notify,
187
188 /*
189 * Lowest-prio notifier priority, we w
190 */
191 .priority = -INT_MAX,
192 };
193
194 /**
195 * kgdb_arch_init - Perform any architecture s
196 *
197 * This function will handle the initializatio
198 * specific callbacks.
199 */
200 int kgdb_arch_init(void)
201 {
202 return register_die_notifier(&kgdb_not
203 }
204
205 /**
206 * kgdb_arch_exit - Perform any architecture s
207 *
208 * This function will handle the uninitalizati
209 * specific callbacks, for dynamic registratio
210 */
211 void kgdb_arch_exit(void)
212 {
213 unregister_die_notifier(&kgdb_notifier
214 }
215
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