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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
24struct 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 */
35extern int kgdb_skipexception(int exception, struct pt_regs *regs);
36
37struct tasklet_struct;
38struct task_struct;
39struct 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 */
49void kgdb_breakpoint(void);
50
51extern int kgdb_connected;
52extern int kgdb_io_module_registered;
53
54extern atomic_t kgdb_setting_breakpoint;
55extern atomic_t kgdb_cpu_doing_single_step;
56
57extern struct task_struct *kgdb_usethread;
58extern struct task_struct *kgdb_contthread;
59
60enum 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
69enum kgdb_bpstate {
70 BP_UNDEFINED = 0,
71 BP_REMOVED,
72 BP_SET,
73 BP_ACTIVE
74};
75
76struct 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
83struct 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
92extern struct dbg_reg_def_t dbg_reg_def[];
93extern char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs);
94extern 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 */
112extern 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 */
120extern 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 */
130extern 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 */
144extern void
145sleeping_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 */
155extern 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 */
173extern int
174kgdb_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_arch_handle_qxfer_pkt - Handle architecture specific GDB XML
181 * packets.
182 * @remcom_in_buffer: The buffer of the packet we have read.
183 * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
184 */
185
186extern void
187kgdb_arch_handle_qxfer_pkt(char *remcom_in_buffer,
188 char *remcom_out_buffer);
189
190/**
191 * kgdb_call_nmi_hook - Call kgdb_nmicallback() on the current CPU
192 * @ignored: This parameter is only here to match the prototype.
193 *
194 * If you're using the default implementation of kgdb_roundup_cpus()
195 * this function will be called per CPU. If you don't implement
196 * kgdb_call_nmi_hook() a default will be used.
197 */
198
199extern void kgdb_call_nmi_hook(void *ignored);
200
201/**
202 * kgdb_roundup_cpus - Get other CPUs into a holding pattern
203 *
204 * On SMP systems, we need to get the attention of the other CPUs
205 * and get them into a known state. This should do what is needed
206 * to get the other CPUs to call kgdb_wait(). Note that on some arches,
207 * the NMI approach is not used for rounding up all the CPUs. Normally
208 * those architectures can just not implement this and get the default.
209 *
210 * On non-SMP systems, this is not called.
211 */
212extern void kgdb_roundup_cpus(void);
213
214/**
215 * kgdb_arch_set_pc - Generic call back to the program counter
216 * @regs: Current &struct pt_regs.
217 * @pc: The new value for the program counter
218 *
219 * This function handles updating the program counter and requires an
220 * architecture specific implementation.
221 */
222extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
223
224
225/* Optional functions. */
226extern int kgdb_validate_break_address(unsigned long addr);
227extern int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt);
228extern int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt);
229
230/**
231 * kgdb_arch_late - Perform any architecture specific initalization.
232 *
233 * This function will handle the late initalization of any
234 * architecture specific callbacks. This is an optional function for
235 * handling things like late initialization of hw breakpoints. The
236 * default implementation does nothing.
237 */
238extern void kgdb_arch_late(void);
239
240
241/**
242 * struct kgdb_arch - Describe architecture specific values.
243 * @gdb_bpt_instr: The instruction to trigger a breakpoint.
244 * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
245 * @set_breakpoint: Allow an architecture to specify how to set a software
246 * breakpoint.
247 * @remove_breakpoint: Allow an architecture to specify how to remove a
248 * software breakpoint.
249 * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
250 * breakpoint.
251 * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
252 * hardware breakpoint.
253 * @disable_hw_break: Allow an architecture to specify how to disable
254 * hardware breakpoints for a single cpu.
255 * @remove_all_hw_break: Allow an architecture to specify how to remove all
256 * hardware breakpoints.
257 * @correct_hw_break: Allow an architecture to specify how to correct the
258 * hardware debug registers.
259 * @enable_nmi: Manage NMI-triggered entry to KGDB
260 */
261struct kgdb_arch {
262 unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
263 unsigned long flags;
264
265 int (*set_breakpoint)(unsigned long, char *);
266 int (*remove_breakpoint)(unsigned long, char *);
267 int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
268 int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
269 void (*disable_hw_break)(struct pt_regs *regs);
270 void (*remove_all_hw_break)(void);
271 void (*correct_hw_break)(void);
272
273 void (*enable_nmi)(bool on);
274};
275
276/**
277 * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
278 * @name: Name of the I/O driver.
279 * @read_char: Pointer to a function that will return one char.
280 * @write_char: Pointer to a function that will write one char.
281 * @flush: Pointer to a function that will flush any pending writes.
282 * @init: Pointer to a function that will initialize the device.
283 * @deinit: Pointer to a function that will deinit the device. Implies that
284 * this I/O driver is temporary and expects to be replaced. Called when
285 * an I/O driver is replaced or explicitly unregistered.
286 * @pre_exception: Pointer to a function that will do any prep work for
287 * the I/O driver.
288 * @post_exception: Pointer to a function that will do any cleanup work
289 * for the I/O driver.
290 * @cons: valid if the I/O device is a console; else NULL.
291 */
292struct kgdb_io {
293 const char *name;
294 int (*read_char) (void);
295 void (*write_char) (u8);
296 void (*flush) (void);
297 int (*init) (void);
298 void (*deinit) (void);
299 void (*pre_exception) (void);
300 void (*post_exception) (void);
301 struct console *cons;
302};
303
304extern const struct kgdb_arch arch_kgdb_ops;
305
306extern unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs);
307
308#ifdef CONFIG_SERIAL_KGDB_NMI
309extern int kgdb_register_nmi_console(void);
310extern int kgdb_unregister_nmi_console(void);
311extern bool kgdb_nmi_poll_knock(void);
312#else
313static inline int kgdb_register_nmi_console(void) { return 0; }
314static inline int kgdb_unregister_nmi_console(void) { return 0; }
315static inline bool kgdb_nmi_poll_knock(void) { return true; }
316#endif
317
318extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
319extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
320extern struct kgdb_io *dbg_io_ops;
321
322extern int kgdb_hex2long(char **ptr, unsigned long *long_val);
323extern char *kgdb_mem2hex(char *mem, char *buf, int count);
324extern int kgdb_hex2mem(char *buf, char *mem, int count);
325
326extern int kgdb_isremovedbreak(unsigned long addr);
327extern void kgdb_schedule_breakpoint(void);
328extern int kgdb_has_hit_break(unsigned long addr);
329
330extern int
331kgdb_handle_exception(int ex_vector, int signo, int err_code,
332 struct pt_regs *regs);
333extern int kgdb_nmicallback(int cpu, void *regs);
334extern int kgdb_nmicallin(int cpu, int trapnr, void *regs, int err_code,
335 atomic_t *snd_rdy);
336extern void gdbstub_exit(int status);
337
338extern int kgdb_single_step;
339extern atomic_t kgdb_active;
340#define in_dbg_master() \
341 (irqs_disabled() && (smp_processor_id() == atomic_read(&kgdb_active)))
342extern bool dbg_is_early;
343extern void __init dbg_late_init(void);
344extern void kgdb_panic(const char *msg);
345#else /* ! CONFIG_KGDB */
346#define in_dbg_master() (0)
347#define dbg_late_init()
348static inline void kgdb_panic(const char *msg) {}
349#endif /* ! CONFIG_KGDB */
350#endif /* _KGDB_H_ */