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_post_primary_code - (optional) Save error vector/code numbers.
40 * @regs: Original pt_regs.
41 * @e_vector: Original error vector.
42 * @err_code: Original error code.
44 * This is usually needed on architectures which support SMP and
45 * KGDB. This function is called after all the secondary cpus have
46 * been put to a know spin state and the primary CPU has control over
49 extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector,
53 * kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
54 * @regs: Current &struct pt_regs.
56 * This function will be called if the particular architecture must
57 * disable hardware debugging while it is processing gdb packets or
60 extern void kgdb_disable_hw_debug(struct pt_regs *regs);
62 struct tasklet_struct;
67 * kgdb_breakpoint - compiled in breakpoint
69 * This will be implemented as a static inline per architecture. This
70 * function is called by the kgdb core to execute an architecture
71 * specific trap to cause kgdb to enter the exception processing.
74 void kgdb_breakpoint(void);
76 extern int kgdb_connected;
78 extern atomic_t kgdb_setting_breakpoint;
79 extern atomic_t kgdb_cpu_doing_single_step;
81 extern struct task_struct *kgdb_usethread;
82 extern struct task_struct *kgdb_contthread;
86 BP_HARDWARE_BREAKPOINT,
100 unsigned long bpt_addr;
101 unsigned char saved_instr[BREAK_INSTR_SIZE];
102 enum kgdb_bptype type;
103 enum kgdb_bpstate state;
106 #ifndef KGDB_MAX_BREAKPOINTS
107 # define KGDB_MAX_BREAKPOINTS 1000
110 #define KGDB_HW_BREAKPOINT 1
113 * Functions each KGDB-supporting architecture must provide:
117 * kgdb_arch_init - Perform any architecture specific initalization.
119 * This function will handle the initalization of any architecture
120 * specific callbacks.
122 extern int kgdb_arch_init(void);
125 * kgdb_arch_exit - Perform any architecture specific uninitalization.
127 * This function will handle the uninitalization of any architecture
128 * specific callbacks, for dynamic registration and unregistration.
130 extern void kgdb_arch_exit(void);
133 * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
134 * @gdb_regs: A pointer to hold the registers in the order GDB wants.
135 * @regs: The &struct pt_regs of the current process.
137 * Convert the pt_regs in @regs into the format for registers that
138 * GDB expects, stored in @gdb_regs.
140 extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);
143 * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
144 * @gdb_regs: A pointer to hold the registers in the order GDB wants.
145 * @p: The &struct task_struct of the desired process.
147 * Convert the register values of the sleeping process in @p to
148 * the format that GDB expects.
149 * This function is called when kgdb does not have access to the
150 * &struct pt_regs and therefore it should fill the gdb registers
151 * @gdb_regs with what has been saved in &struct thread_struct
152 * thread field during switch_to.
155 sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);
158 * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
159 * @gdb_regs: A pointer to hold the registers we've received from GDB.
160 * @regs: A pointer to a &struct pt_regs to hold these values in.
162 * Convert the GDB regs in @gdb_regs into the pt_regs, and store them
165 extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);
168 * kgdb_arch_handle_exception - Handle architecture specific GDB packets.
169 * @vector: The error vector of the exception that happened.
170 * @signo: The signal number of the exception that happened.
171 * @err_code: The error code of the exception that happened.
172 * @remcom_in_buffer: The buffer of the packet we have read.
173 * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
174 * @regs: The &struct pt_regs of the current process.
176 * This function MUST handle the 'c' and 's' command packets,
177 * as well packets to set / remove a hardware breakpoint, if used.
178 * If there are additional packets which the hardware needs to handle,
179 * they are handled here. The code should return -1 if it wants to
180 * process more packets, and a %0 or %1 if it wants to exit from the
184 kgdb_arch_handle_exception(int vector, int signo, int err_code,
185 char *remcom_in_buffer,
186 char *remcom_out_buffer,
187 struct pt_regs *regs);
190 * kgdb_roundup_cpus - Get other CPUs into a holding pattern
191 * @flags: Current IRQ state
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. For example,
197 * in case of MIPS, smp_call_function() is used to roundup CPUs. In
198 * this case, we have to make sure that interrupts are enabled before
199 * calling smp_call_function(). The argument to this function is
200 * the flags that will be used when restoring the interrupts. There is
201 * local_irq_save() call before kgdb_roundup_cpus().
203 * On non-SMP systems, this is not called.
205 extern void kgdb_roundup_cpus(unsigned long flags);
208 * kgdb_arch_set_pc - Generic call back to the program counter
209 * @regs: Current &struct pt_regs.
210 * @pc: The new value for the program counter
212 * This function handles updating the program counter and requires an
213 * architecture specific implementation.
215 extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
218 /* Optional functions. */
219 extern int kgdb_validate_break_address(unsigned long addr);
220 extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
221 extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);
224 * struct kgdb_arch - Describe architecture specific values.
225 * @gdb_bpt_instr: The instruction to trigger a breakpoint.
226 * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
227 * @set_breakpoint: Allow an architecture to specify how to set a software
229 * @remove_breakpoint: Allow an architecture to specify how to remove a
230 * software breakpoint.
231 * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
233 * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
234 * hardware breakpoint.
235 * @remove_all_hw_break: Allow an architecture to specify how to remove all
236 * hardware breakpoints.
237 * @correct_hw_break: Allow an architecture to specify how to correct the
238 * hardware debug registers.
241 unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
244 int (*set_breakpoint)(unsigned long, char *);
245 int (*remove_breakpoint)(unsigned long, char *);
246 int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
247 int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
248 void (*remove_all_hw_break)(void);
249 void (*correct_hw_break)(void);
253 * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
254 * @name: Name of the I/O driver.
255 * @read_char: Pointer to a function that will return one char.
256 * @write_char: Pointer to a function that will write one char.
257 * @flush: Pointer to a function that will flush any pending writes.
258 * @init: Pointer to a function that will initialize the device.
259 * @pre_exception: Pointer to a function that will do any prep work for
261 * @post_exception: Pointer to a function that will do any cleanup work
262 * for the I/O driver.
266 int (*read_char) (void);
267 void (*write_char) (u8);
268 void (*flush) (void);
270 void (*pre_exception) (void);
271 void (*post_exception) (void);
274 extern struct kgdb_arch arch_kgdb_ops;
276 extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
278 extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
279 extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
280 extern struct kgdb_io *dbg_io_ops;
282 extern int kgdb_hex2long(char **ptr, unsigned long *long_val);
283 extern int kgdb_mem2hex(char *mem, char *buf, int count);
284 extern int kgdb_hex2mem(char *buf, char *mem, int count);
286 extern int kgdb_isremovedbreak(unsigned long addr);
289 kgdb_handle_exception(int ex_vector, int signo, int err_code,
290 struct pt_regs *regs);
291 extern int kgdb_nmicallback(int cpu, void *regs);
293 extern int kgdb_single_step;
294 extern atomic_t kgdb_active;
295 #define in_dbg_master() \
296 (raw_smp_processor_id() == atomic_read(&kgdb_active))
297 #else /* ! CONFIG_KGDB */
298 #define in_dbg_master() (0)
299 #endif /* ! CONFIG_KGDB */
300 #endif /* _KGDB_H_ */