1 | /* |
2 | * This provides the callbacks and functions that KGDB needs to share between |
3 | * the core, I/O and arch-specific portions. |
4 | * |
5 | * Author: Amit Kale <amitkale@linsyssoft.com> and |
6 | * Tom Rini <trini@kernel.crashing.org> |
7 | * |
8 | * 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc. |
9 | * This file is licensed under the terms of the GNU General Public License |
10 | * version 2. This program is licensed "as is" without any warranty of any |
11 | * kind, whether express or implied. |
12 | */ |
13 | #ifndef _KGDB_H_ |
14 | #define _KGDB_H_ |
15 | |
16 | #include <linux/linkage.h> |
17 | #include <linux/init.h> |
18 | #include <linux/atomic.h> |
19 | #ifdef CONFIG_HAVE_ARCH_KGDB |
20 | #include <asm/kgdb.h> |
21 | #endif |
22 | |
23 | #ifdef CONFIG_KGDB |
24 | struct pt_regs; |
25 | |
26 | /** |
27 | * kgdb_skipexception - (optional) exit kgdb_handle_exception early |
28 | * @exception: Exception vector number |
29 | * @regs: Current &struct pt_regs. |
30 | * |
31 | * On some architectures it is required to skip a breakpoint |
32 | * exception when it occurs after a breakpoint has been removed. |
33 | * This can be implemented in the architecture specific portion of kgdb. |
34 | */ |
35 | extern int kgdb_skipexception(int exception, struct pt_regs *regs); |
36 | |
37 | struct tasklet_struct; |
38 | struct task_struct; |
39 | struct uart_port; |
40 | |
41 | /** |
42 | * kgdb_breakpoint - compiled in breakpoint |
43 | * |
44 | * This will be implemented as a static inline per architecture. This |
45 | * function is called by the kgdb core to execute an architecture |
46 | * specific trap to cause kgdb to enter the exception processing. |
47 | * |
48 | */ |
49 | void kgdb_breakpoint(void); |
50 | |
51 | extern int kgdb_connected; |
52 | extern int kgdb_io_module_registered; |
53 | |
54 | extern atomic_t kgdb_setting_breakpoint; |
55 | extern atomic_t kgdb_cpu_doing_single_step; |
56 | |
57 | extern struct task_struct *kgdb_usethread; |
58 | extern struct task_struct *kgdb_contthread; |
59 | |
60 | enum kgdb_bptype { |
61 | BP_BREAKPOINT = 0, |
62 | BP_HARDWARE_BREAKPOINT, |
63 | BP_WRITE_WATCHPOINT, |
64 | BP_READ_WATCHPOINT, |
65 | BP_ACCESS_WATCHPOINT, |
66 | BP_POKE_BREAKPOINT, |
67 | }; |
68 | |
69 | enum kgdb_bpstate { |
70 | BP_UNDEFINED = 0, |
71 | BP_REMOVED, |
72 | BP_SET, |
73 | BP_ACTIVE |
74 | }; |
75 | |
76 | struct kgdb_bkpt { |
77 | unsigned long bpt_addr; |
78 | unsigned char saved_instr[BREAK_INSTR_SIZE]; |
79 | enum kgdb_bptype type; |
80 | enum kgdb_bpstate state; |
81 | }; |
82 | |
83 | struct dbg_reg_def_t { |
84 | char *name; |
85 | int size; |
86 | int offset; |
87 | }; |
88 | |
89 | #ifndef DBG_MAX_REG_NUM |
90 | #define DBG_MAX_REG_NUM 0 |
91 | #else |
92 | extern struct dbg_reg_def_t dbg_reg_def[]; |
93 | extern char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs); |
94 | extern int dbg_set_reg(int regno, void *mem, struct pt_regs *regs); |
95 | #endif |
96 | #ifndef KGDB_MAX_BREAKPOINTS |
97 | # define KGDB_MAX_BREAKPOINTS 1000 |
98 | #endif |
99 | |
100 | #define KGDB_HW_BREAKPOINT 1 |
101 | |
102 | /* |
103 | * Functions each KGDB-supporting architecture must provide: |
104 | */ |
105 | |
106 | /** |
107 | * kgdb_arch_init - Perform any architecture specific initalization. |
108 | * |
109 | * This function will handle the initalization of any architecture |
110 | * specific callbacks. |
111 | */ |
112 | extern int kgdb_arch_init(void); |
113 | |
114 | /** |
115 | * kgdb_arch_exit - Perform any architecture specific uninitalization. |
116 | * |
117 | * This function will handle the uninitalization of any architecture |
118 | * specific callbacks, for dynamic registration and unregistration. |
119 | */ |
120 | extern void kgdb_arch_exit(void); |
121 | |
122 | /** |
123 | * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs |
124 | * @gdb_regs: A pointer to hold the registers in the order GDB wants. |
125 | * @regs: The &struct pt_regs of the current process. |
126 | * |
127 | * Convert the pt_regs in @regs into the format for registers that |
128 | * GDB expects, stored in @gdb_regs. |
129 | */ |
130 | extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs); |
131 | |
132 | /** |
133 | * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs |
134 | * @gdb_regs: A pointer to hold the registers in the order GDB wants. |
135 | * @p: The &struct task_struct of the desired process. |
136 | * |
137 | * Convert the register values of the sleeping process in @p to |
138 | * the format that GDB expects. |
139 | * This function is called when kgdb does not have access to the |
140 | * &struct pt_regs and therefore it should fill the gdb registers |
141 | * @gdb_regs with what has been saved in &struct thread_struct |
142 | * thread field during switch_to. |
143 | */ |
144 | extern void |
145 | sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p); |
146 | |
147 | /** |
148 | * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs. |
149 | * @gdb_regs: A pointer to hold the registers we've received from GDB. |
150 | * @regs: A pointer to a &struct pt_regs to hold these values in. |
151 | * |
152 | * Convert the GDB regs in @gdb_regs into the pt_regs, and store them |
153 | * in @regs. |
154 | */ |
155 | extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs); |
156 | |
157 | /** |
158 | * kgdb_arch_handle_exception - Handle architecture specific GDB packets. |
159 | * @vector: The error vector of the exception that happened. |
160 | * @signo: The signal number of the exception that happened. |
161 | * @err_code: The error code of the exception that happened. |
162 | * @remcom_in_buffer: The buffer of the packet we have read. |
163 | * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into. |
164 | * @regs: The &struct pt_regs of the current process. |
165 | * |
166 | * This function MUST handle the 'c' and 's' command packets, |
167 | * as well packets to set / remove a hardware breakpoint, if used. |
168 | * If there are additional packets which the hardware needs to handle, |
169 | * they are handled here. The code should return -1 if it wants to |
170 | * process more packets, and a %0 or %1 if it wants to exit from the |
171 | * kgdb callback. |
172 | */ |
173 | extern int |
174 | kgdb_arch_handle_exception(int vector, int signo, int err_code, |
175 | char *remcom_in_buffer, |
176 | char *remcom_out_buffer, |
177 | struct pt_regs *regs); |
178 | |
179 | /** |
180 | * kgdb_call_nmi_hook - Call kgdb_nmicallback() on the current CPU |
181 | * @ignored: This parameter is only here to match the prototype. |
182 | * |
183 | * If you're using the default implementation of kgdb_roundup_cpus() |
184 | * this function will be called per CPU. If you don't implement |
185 | * kgdb_call_nmi_hook() a default will be used. |
186 | */ |
187 | |
188 | extern void kgdb_call_nmi_hook(void *ignored); |
189 | |
190 | /** |
191 | * kgdb_roundup_cpus - Get other CPUs into a holding pattern |
192 | * |
193 | * On SMP systems, we need to get the attention of the other CPUs |
194 | * and get them into a known state. This should do what is needed |
195 | * to get the other CPUs to call kgdb_wait(). Note that on some arches, |
196 | * the NMI approach is not used for rounding up all the CPUs. Normally |
197 | * those architectures can just not implement this and get the default. |
198 | * |
199 | * On non-SMP systems, this is not called. |
200 | */ |
201 | extern void kgdb_roundup_cpus(void); |
202 | |
203 | /** |
204 | * kgdb_arch_set_pc - Generic call back to the program counter |
205 | * @regs: Current &struct pt_regs. |
206 | * @pc: The new value for the program counter |
207 | * |
208 | * This function handles updating the program counter and requires an |
209 | * architecture specific implementation. |
210 | */ |
211 | extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc); |
212 | |
213 | |
214 | /* Optional functions. */ |
215 | extern int kgdb_validate_break_address(unsigned long addr); |
216 | extern int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt); |
217 | extern int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt); |
218 | |
219 | /** |
220 | * kgdb_arch_late - Perform any architecture specific initalization. |
221 | * |
222 | * This function will handle the late initalization of any |
223 | * architecture specific callbacks. This is an optional function for |
224 | * handling things like late initialization of hw breakpoints. The |
225 | * default implementation does nothing. |
226 | */ |
227 | extern void kgdb_arch_late(void); |
228 | |
229 | |
230 | /** |
231 | * struct kgdb_arch - Describe architecture specific values. |
232 | * @gdb_bpt_instr: The instruction to trigger a breakpoint. |
233 | * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT. |
234 | * @set_breakpoint: Allow an architecture to specify how to set a software |
235 | * breakpoint. |
236 | * @remove_breakpoint: Allow an architecture to specify how to remove a |
237 | * software breakpoint. |
238 | * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware |
239 | * breakpoint. |
240 | * @remove_hw_breakpoint: Allow an architecture to specify how to remove a |
241 | * hardware breakpoint. |
242 | * @disable_hw_break: Allow an architecture to specify how to disable |
243 | * hardware breakpoints for a single cpu. |
244 | * @remove_all_hw_break: Allow an architecture to specify how to remove all |
245 | * hardware breakpoints. |
246 | * @correct_hw_break: Allow an architecture to specify how to correct the |
247 | * hardware debug registers. |
248 | * @enable_nmi: Manage NMI-triggered entry to KGDB |
249 | */ |
250 | struct kgdb_arch { |
251 | unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE]; |
252 | unsigned long flags; |
253 | |
254 | int (*set_breakpoint)(unsigned long, char *); |
255 | int (*remove_breakpoint)(unsigned long, char *); |
256 | int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype); |
257 | int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype); |
258 | void (*disable_hw_break)(struct pt_regs *regs); |
259 | void (*remove_all_hw_break)(void); |
260 | void (*correct_hw_break)(void); |
261 | |
262 | void (*enable_nmi)(bool on); |
263 | }; |
264 | |
265 | /** |
266 | * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB. |
267 | * @name: Name of the I/O driver. |
268 | * @read_char: Pointer to a function that will return one char. |
269 | * @write_char: Pointer to a function that will write one char. |
270 | * @flush: Pointer to a function that will flush any pending writes. |
271 | * @init: Pointer to a function that will initialize the device. |
272 | * @pre_exception: Pointer to a function that will do any prep work for |
273 | * the I/O driver. |
274 | * @post_exception: Pointer to a function that will do any cleanup work |
275 | * for the I/O driver. |
276 | * @is_console: 1 if the end device is a console 0 if the I/O device is |
277 | * not a console |
278 | */ |
279 | struct kgdb_io { |
280 | const char *name; |
281 | int (*read_char) (void); |
282 | void (*write_char) (u8); |
283 | void (*flush) (void); |
284 | int (*init) (void); |
285 | void (*pre_exception) (void); |
286 | void (*post_exception) (void); |
287 | int is_console; |
288 | }; |
289 | |
290 | extern const struct kgdb_arch arch_kgdb_ops; |
291 | |
292 | extern unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs); |
293 | |
294 | #ifdef CONFIG_SERIAL_KGDB_NMI |
295 | extern int kgdb_register_nmi_console(void); |
296 | extern int kgdb_unregister_nmi_console(void); |
297 | extern bool kgdb_nmi_poll_knock(void); |
298 | #else |
299 | static inline int kgdb_register_nmi_console(void) { return 0; } |
300 | static inline int kgdb_unregister_nmi_console(void) { return 0; } |
301 | static inline bool kgdb_nmi_poll_knock(void) { return 1; } |
302 | #endif |
303 | |
304 | extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops); |
305 | extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops); |
306 | extern struct kgdb_io *dbg_io_ops; |
307 | |
308 | extern int kgdb_hex2long(char **ptr, unsigned long *long_val); |
309 | extern char *kgdb_mem2hex(char *mem, char *buf, int count); |
310 | extern int kgdb_hex2mem(char *buf, char *mem, int count); |
311 | |
312 | extern int kgdb_isremovedbreak(unsigned long addr); |
313 | extern void kgdb_schedule_breakpoint(void); |
314 | |
315 | extern int |
316 | kgdb_handle_exception(int ex_vector, int signo, int err_code, |
317 | struct pt_regs *regs); |
318 | extern int kgdb_nmicallback(int cpu, void *regs); |
319 | extern int kgdb_nmicallin(int cpu, int trapnr, void *regs, int err_code, |
320 | atomic_t *snd_rdy); |
321 | extern void gdbstub_exit(int status); |
322 | |
323 | extern int kgdb_single_step; |
324 | extern atomic_t kgdb_active; |
325 | #define in_dbg_master() \ |
326 | (raw_smp_processor_id() == atomic_read(&kgdb_active)) |
327 | extern bool dbg_is_early; |
328 | extern void __init dbg_late_init(void); |
329 | #else /* ! CONFIG_KGDB */ |
330 | #define in_dbg_master() (0) |
331 | #define dbg_late_init() |
332 | #endif /* ! CONFIG_KGDB */ |
333 | #endif /* _KGDB_H_ */ |
334 | |