/*
* This provides the callbacks and functions that KGDB needs to share between
* the core, I/O and arch-specific portions.
*
* Author: Amit Kale <amitkale@linsyssoft.com> and
* Tom Rini <trini@kernel.crashing.org>
*
* 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc.
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#ifndef _KGDB_H_
#define _KGDB_H_
#include <linux/serial_8250.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/atomic.h>
#ifdef CONFIG_HAVE_ARCH_KGDB
#include <asm/kgdb.h>
#endif
#ifdef CONFIG_KGDB
struct pt_regs;
/**
* kgdb_skipexception - (optional) exit kgdb_handle_exception early
* @exception: Exception vector number
* @regs: Current &struct pt_regs.
*
* On some architectures it is required to skip a breakpoint
* exception when it occurs after a breakpoint has been removed.
* This can be implemented in the architecture specific portion of kgdb.
*/
extern int kgdb_skipexception(int exception, struct pt_regs *regs);
struct tasklet_struct;
struct task_struct;
struct uart_port;
/**
* kgdb_breakpoint - compiled in breakpoint
*
* This will be implemented as a static inline per architecture. This
* function is called by the kgdb core to execute an architecture
* specific trap to cause kgdb to enter the exception processing.
*
*/
void kgdb_breakpoint(void);
extern int kgdb_connected;
extern int kgdb_io_module_registered;
extern atomic_t kgdb_setting_breakpoint;
extern atomic_t kgdb_cpu_doing_single_step;
extern struct task_struct *kgdb_usethread;
extern struct task_struct *kgdb_contthread;
enum kgdb_bptype {
BP_BREAKPOINT = 0,
BP_HARDWARE_BREAKPOINT,
BP_WRITE_WATCHPOINT,
BP_READ_WATCHPOINT,
BP_ACCESS_WATCHPOINT
};
enum kgdb_bpstate {
BP_UNDEFINED = 0,
BP_REMOVED,
BP_SET,
BP_ACTIVE
};
struct kgdb_bkpt {
unsigned long bpt_addr;
unsigned char saved_instr[BREAK_INSTR_SIZE];
enum kgdb_bptype type;
enum kgdb_bpstate state;
};
struct dbg_reg_def_t {
char *name;
int size;
int offset;
};
#ifndef DBG_MAX_REG_NUM
#define DBG_MAX_REG_NUM 0
#else
extern struct dbg_reg_def_t dbg_reg_def[];
extern char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs);
extern int dbg_set_reg(int regno, void *mem, struct pt_regs *regs);
#endif
#ifndef KGDB_MAX_BREAKPOINTS
# define KGDB_MAX_BREAKPOINTS 1000
#endif
#define KGDB_HW_BREAKPOINT 1
/*
* Functions each KGDB-supporting architecture must provide:
*/
/**
* kgdb_arch_init - Perform any architecture specific initalization.
*
* This function will handle the initalization of any architecture
* specific callbacks.
*/
extern int kgdb_arch_init(void);
/**
* kgdb_arch_exit - Perform any architecture specific uninitalization.
*
* This function will handle the uninitalization of any architecture
* specific callbacks, for dynamic registration and unregistration.
*/
extern void kgdb_arch_exit(void);
/**
* pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
* @gdb_regs: A pointer to hold the registers in the order GDB wants.
* @regs: The &struct pt_regs of the current process.
*
* Convert the pt_regs in @regs into the format for registers that
* GDB expects, stored in @gdb_regs.
*/
extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);
/**
* sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
* @gdb_regs: A pointer to hold the registers in the order GDB wants.
* @p: The &struct task_struct of the desired process.
*
* Convert the register values of the sleeping process in @p to
* the format that GDB expects.
* This function is called when kgdb does not have access to the
* &struct pt_regs and therefore it should fill the gdb registers
* @gdb_regs with what has been saved in &struct thread_struct
* thread field during switch_to.
*/
extern void
sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);
/**
* gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
* @gdb_regs: A pointer to hold the registers we've received from GDB.
* @regs: A pointer to a &struct pt_regs to hold these values in.
*
* Convert the GDB regs in @gdb_regs into the pt_regs, and store them
* in @regs.
*/
extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);
/**
* kgdb_arch_handle_exception - Handle architecture specific GDB packets.
* @vector: The error vector of the exception that happened.
* @signo: The signal number of the exception that happened.
* @err_code: The error code of the exception that happened.
* @remcom_in_buffer: The buffer of the packet we have read.
* @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
* @regs: The &struct pt_regs of the current process.
*
* This function MUST handle the 'c' and 's' command packets,
* as well packets to set / remove a hardware breakpoint, if used.
* If there are additional packets which the hardware needs to handle,
* they are handled here. The code should return -1 if it wants to
* process more packets, and a %0 or %1 if it wants to exit from the
* kgdb callback.
*/
extern int
kgdb_arch_handle_exception(int vector, int signo, int err_code,
char *remcom_in_buffer,
char *remcom_out_buffer,
struct pt_regs *regs);
/**
* kgdb_roundup_cpus - Get other CPUs into a holding pattern
* @flags: Current IRQ state
*
* On SMP systems, we need to get the attention of the other CPUs
* and get them into a known state. This should do what is needed
* to get the other CPUs to call kgdb_wait(). Note that on some arches,
* the NMI approach is not used for rounding up all the CPUs. For example,
* in case of MIPS, smp_call_function() is used to roundup CPUs. In
* this case, we have to make sure that interrupts are enabled before
* calling smp_call_function(). The argument to this function is
* the flags that will be used when restoring the interrupts. There is
* local_irq_save() call before kgdb_roundup_cpus().
*
* On non-SMP systems, this is not called.
*/
extern void kgdb_roundup_cpus(unsigned long flags);
/**
* kgdb_arch_set_pc - Generic call back to the program counter
* @regs: Current &struct pt_regs.
* @pc: The new value for the program counter
*
* This function handles updating the program counter and requires an
* architecture specific implementation.
*/
extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
/* Optional functions. */
extern int kgdb_validate_break_address(unsigned long addr);
extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);
/**
* kgdb_arch_late - Perform any architecture specific initalization.
*
* This function will handle the late initalization of any
* architecture specific callbacks. This is an optional function for
* handling things like late initialization of hw breakpoints. The
* default implementation does nothing.
*/
extern void kgdb_arch_late(void);
/**
* struct kgdb_arch - Describe architecture specific values.
* @gdb_bpt_instr: The instruction to trigger a breakpoint.
* @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
* @set_breakpoint: Allow an architecture to specify how to set a software
* breakpoint.
* @remove_breakpoint: Allow an architecture to specify how to remove a
* software breakpoint.
* @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
* breakpoint.
* @remove_hw_breakpoint: Allow an architecture to specify how to remove a
* hardware breakpoint.
* @disable_hw_break: Allow an architecture to specify how to disable
* hardware breakpoints for a single cpu.
* @remove_all_hw_break: Allow an architecture to specify how to remove all
* hardware breakpoints.
* @correct_hw_break: Allow an architecture to specify how to correct the
* hardware debug registers.
*/
struct kgdb_arch {
unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
unsigned long flags;
int (*set_breakpoint)(unsigned long, char *);
int (*remove_breakpoint)(unsigned long, char *);
int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
void (*disable_hw_break)(struct pt_regs *regs);
void (*remove_all_hw_break)(void);
void (*correct_hw_break)(void);
};
/**
* struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
* @name: Name of the I/O driver.
* @read_char: Pointer to a function that will return one char.
* @write_char: Pointer to a function that will write one char.
* @flush: Pointer to a function that will flush any pending writes.
* @init: Pointer to a function that will initialize the device.
* @pre_exception: Pointer to a function that will do any prep work for
* the I/O driver.
* @post_exception: Pointer to a function that will do any cleanup work
* for the I/O driver.
* @is_console: 1 if the end device is a console 0 if the I/O device is
* not a console
*/
struct kgdb_io {
const char *name;
int (*read_char) (void);
void (*write_char) (u8);
void (*flush) (void);
int (*init) (void);
void (*pre_exception) (void);
void (*post_exception) (void);
int is_console;
};
extern struct kgdb_arch arch_kgdb_ops;
extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
extern struct kgdb_io *dbg_io_ops;
extern int kgdb_hex2long(char **ptr, unsigned long *long_val);
extern char *kgdb_mem2hex(char *mem, char *buf, int count);
extern int kgdb_hex2mem(char *buf, char *mem, int count);
extern int kgdb_isremovedbreak(unsigned long addr);
extern void kgdb_schedule_breakpoint(void);
extern int
kgdb_handle_exception(int ex_vector, int signo, int err_code,
struct pt_regs *regs);
extern int kgdb_nmicallback(int cpu, void *regs);
extern int kgdb_single_step;
extern atomic_t kgdb_active;
#define in_dbg_master() \
(raw_smp_processor_id() == atomic_read(&kgdb_active))
extern bool dbg_is_early;
extern void __init dbg_late_init(void);
#else /* ! CONFIG_KGDB */
#define in_dbg_master() (0)
#define dbg_late_init()
#endif /* ! CONFIG_KGDB */
#endif /* _KGDB_H_ */
