2 * This provides the callbacks and functions that KGDB needs to share between
3 * the core, I/O and arch-specific portions.
5 * Author: Amit Kale <amitkale@linsyssoft.com> and
6 * Tom Rini <trini@kernel.crashing.org>
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.
16 #include <linux/serial_8250.h>
17 #include <linux/linkage.h>
18 #include <linux/init.h>
19 #include <asm/atomic.h>
20 #ifdef CONFIG_HAVE_ARCH_KGDB
28 * kgdb_skipexception - (optional) exit kgdb_handle_exception early
29 * @exception: Exception vector number
30 * @regs: Current &struct pt_regs.
32 * On some architectures it is required to skip a breakpoint
33 * exception when it occurs after a breakpoint has been removed.
34 * This can be implemented in the architecture specific portion of kgdb.
36 extern int kgdb_skipexception(int exception, struct pt_regs *regs);
39 * kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
40 * @regs: Current &struct pt_regs.
42 * This function will be called if the particular architecture must
43 * disable hardware debugging while it is processing gdb packets or
46 extern void kgdb_disable_hw_debug(struct pt_regs *regs);
48 struct tasklet_struct;
53 * kgdb_breakpoint - compiled in breakpoint
55 * This will be implemented as a static inline per architecture. This
56 * function is called by the kgdb core to execute an architecture
57 * specific trap to cause kgdb to enter the exception processing.
60 void kgdb_breakpoint(void);
62 extern int kgdb_connected;
63 extern int kgdb_io_module_registered;
65 extern atomic_t kgdb_setting_breakpoint;
66 extern atomic_t kgdb_cpu_doing_single_step;
68 extern struct task_struct *kgdb_usethread;
69 extern struct task_struct *kgdb_contthread;
73 BP_HARDWARE_BREAKPOINT,
87 unsigned long bpt_addr;
88 unsigned char saved_instr[BREAK_INSTR_SIZE];
89 enum kgdb_bptype type;
90 enum kgdb_bpstate state;
93 #ifndef KGDB_MAX_BREAKPOINTS
94 # define KGDB_MAX_BREAKPOINTS 1000
97 #define KGDB_HW_BREAKPOINT 1
100 * Functions each KGDB-supporting architecture must provide:
104 * kgdb_arch_init - Perform any architecture specific initalization.
106 * This function will handle the initalization of any architecture
107 * specific callbacks.
109 extern int kgdb_arch_init(void);
112 * kgdb_arch_exit - Perform any architecture specific uninitalization.
114 * This function will handle the uninitalization of any architecture
115 * specific callbacks, for dynamic registration and unregistration.
117 extern void kgdb_arch_exit(void);
120 * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
121 * @gdb_regs: A pointer to hold the registers in the order GDB wants.
122 * @regs: The &struct pt_regs of the current process.
124 * Convert the pt_regs in @regs into the format for registers that
125 * GDB expects, stored in @gdb_regs.
127 extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);
130 * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
131 * @gdb_regs: A pointer to hold the registers in the order GDB wants.
132 * @p: The &struct task_struct of the desired process.
134 * Convert the register values of the sleeping process in @p to
135 * the format that GDB expects.
136 * This function is called when kgdb does not have access to the
137 * &struct pt_regs and therefore it should fill the gdb registers
138 * @gdb_regs with what has been saved in &struct thread_struct
139 * thread field during switch_to.
142 sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);
145 * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
146 * @gdb_regs: A pointer to hold the registers we've received from GDB.
147 * @regs: A pointer to a &struct pt_regs to hold these values in.
149 * Convert the GDB regs in @gdb_regs into the pt_regs, and store them
152 extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);
155 * kgdb_arch_handle_exception - Handle architecture specific GDB packets.
156 * @vector: The error vector of the exception that happened.
157 * @signo: The signal number of the exception that happened.
158 * @err_code: The error code of the exception that happened.
159 * @remcom_in_buffer: The buffer of the packet we have read.
160 * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
161 * @regs: The &struct pt_regs of the current process.
163 * This function MUST handle the 'c' and 's' command packets,
164 * as well packets to set / remove a hardware breakpoint, if used.
165 * If there are additional packets which the hardware needs to handle,
166 * they are handled here. The code should return -1 if it wants to
167 * process more packets, and a %0 or %1 if it wants to exit from the
171 kgdb_arch_handle_exception(int vector, int signo, int err_code,
172 char *remcom_in_buffer,
173 char *remcom_out_buffer,
174 struct pt_regs *regs);
177 * kgdb_roundup_cpus - Get other CPUs into a holding pattern
178 * @flags: Current IRQ state
180 * On SMP systems, we need to get the attention of the other CPUs
181 * and get them into a known state. This should do what is needed
182 * to get the other CPUs to call kgdb_wait(). Note that on some arches,
183 * the NMI approach is not used for rounding up all the CPUs. For example,
184 * in case of MIPS, smp_call_function() is used to roundup CPUs. In
185 * this case, we have to make sure that interrupts are enabled before
186 * calling smp_call_function(). The argument to this function is
187 * the flags that will be used when restoring the interrupts. There is
188 * local_irq_save() call before kgdb_roundup_cpus().
190 * On non-SMP systems, this is not called.
192 extern void kgdb_roundup_cpus(unsigned long flags);
195 * kgdb_arch_set_pc - Generic call back to the program counter
196 * @regs: Current &struct pt_regs.
197 * @pc: The new value for the program counter
199 * This function handles updating the program counter and requires an
200 * architecture specific implementation.
202 extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
205 /* Optional functions. */
206 extern int kgdb_validate_break_address(unsigned long addr);
207 extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
208 extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);
211 * struct kgdb_arch - Describe architecture specific values.
212 * @gdb_bpt_instr: The instruction to trigger a breakpoint.
213 * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
214 * @set_breakpoint: Allow an architecture to specify how to set a software
216 * @remove_breakpoint: Allow an architecture to specify how to remove a
217 * software breakpoint.
218 * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
220 * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
221 * hardware breakpoint.
222 * @remove_all_hw_break: Allow an architecture to specify how to remove all
223 * hardware breakpoints.
224 * @correct_hw_break: Allow an architecture to specify how to correct the
225 * hardware debug registers.
228 unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
231 int (*set_breakpoint)(unsigned long, char *);
232 int (*remove_breakpoint)(unsigned long, char *);
233 int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
234 int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
235 void (*remove_all_hw_break)(void);
236 void (*correct_hw_break)(void);
240 * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
241 * @name: Name of the I/O driver.
242 * @read_char: Pointer to a function that will return one char.
243 * @write_char: Pointer to a function that will write one char.
244 * @flush: Pointer to a function that will flush any pending writes.
245 * @init: Pointer to a function that will initialize the device.
246 * @pre_exception: Pointer to a function that will do any prep work for
248 * @post_exception: Pointer to a function that will do any cleanup work
249 * for the I/O driver.
250 * @is_console: 1 if the end device is a console 0 if the I/O device is
255 int (*read_char) (void);
256 void (*write_char) (u8);
257 void (*flush) (void);
259 void (*pre_exception) (void);
260 void (*post_exception) (void);
264 extern struct kgdb_arch arch_kgdb_ops;
266 extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
268 extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
269 extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
270 extern struct kgdb_io *dbg_io_ops;
272 extern int kgdb_hex2long(char **ptr, unsigned long *long_val);
273 extern int kgdb_mem2hex(char *mem, char *buf, int count);
274 extern int kgdb_hex2mem(char *buf, char *mem, int count);
276 extern int kgdb_isremovedbreak(unsigned long addr);
277 extern void kgdb_schedule_breakpoint(void);
280 kgdb_handle_exception(int ex_vector, int signo, int err_code,
281 struct pt_regs *regs);
282 extern int kgdb_nmicallback(int cpu, void *regs);
284 extern int kgdb_single_step;
285 extern atomic_t kgdb_active;
286 #define in_dbg_master() \
287 (raw_smp_processor_id() == atomic_read(&kgdb_active))
288 #else /* ! CONFIG_KGDB */
289 #define in_dbg_master() (0)
290 #endif /* ! CONFIG_KGDB */
291 #endif /* _KGDB_H_ */