/*
* arch/arm/kernel/kgdb.c
*
* ARM KGDB support
*
* Copyright (c) 2002-2004 MontaVista Software, Inc
* Copyright (c) 2008 Wind River Systems, Inc.
*
* Authors: George Davis <davis_g@mvista.com>
* Deepak Saxena <dsaxena@plexity.net>
*/
#include <linux/kgdb.h>
#include <asm/traps.h>
/* Make a local copy of the registers passed into the handler (bletch) */
void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
{
int regno;
/* Initialize all to zero. */
for (regno = 0; regno < GDB_MAX_REGS; regno++)
gdb_regs[regno] = 0;
gdb_regs[_R0] = kernel_regs->ARM_r0;
gdb_regs[_R1] = kernel_regs->ARM_r1;
gdb_regs[_R2] = kernel_regs->ARM_r2;
gdb_regs[_R3] = kernel_regs->ARM_r3;
gdb_regs[_R4] = kernel_regs->ARM_r4;
gdb_regs[_R5] = kernel_regs->ARM_r5;
gdb_regs[_R6] = kernel_regs->ARM_r6;
gdb_regs[_R7] = kernel_regs->ARM_r7;
gdb_regs[_R8] = kernel_regs->ARM_r8;
gdb_regs[_R9] = kernel_regs->ARM_r9;
gdb_regs[_R10] = kernel_regs->ARM_r10;
gdb_regs[_FP] = kernel_regs->ARM_fp;
gdb_regs[_IP] = kernel_regs->ARM_ip;
gdb_regs[_SPT] = kernel_regs->ARM_sp;
gdb_regs[_LR] = kernel_regs->ARM_lr;
gdb_regs[_PC] = kernel_regs->ARM_pc;
gdb_regs[_CPSR] = kernel_regs->ARM_cpsr;
}
/* Copy local gdb registers back to kgdb regs, for later copy to kernel */
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
{
kernel_regs->ARM_r0 = gdb_regs[_R0];
kernel_regs->ARM_r1 = gdb_regs[_R1];
kernel_regs->ARM_r2 = gdb_regs[_R2];
kernel_regs->ARM_r3 = gdb_regs[_R3];
kernel_regs->ARM_r4 = gdb_regs[_R4];
kernel_regs->ARM_r5 = gdb_regs[_R5];
kernel_regs->ARM_r6 = gdb_regs[_R6];
kernel_regs->ARM_r7 = gdb_regs[_R7];
kernel_regs->ARM_r8 = gdb_regs[_R8];
kernel_regs->ARM_r9 = gdb_regs[_R9];
kernel_regs->ARM_r10 = gdb_regs[_R10];
kernel_regs->ARM_fp = gdb_regs[_FP];
kernel_regs->ARM_ip = gdb_regs[_IP];
kernel_regs->ARM_sp = gdb_regs[_SPT];
kernel_regs->ARM_lr = gdb_regs[_LR];
kernel_regs->ARM_pc = gdb_regs[_PC];
kernel_regs->ARM_cpsr = gdb_regs[_CPSR];
}
void
sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
{
struct pt_regs *thread_regs;
int regno;
/* Just making sure... */
if (task == NULL)
return;
/* Initialize to zero */
for (regno = 0; regno < GDB_MAX_REGS; regno++)
gdb_regs[regno] = 0;
/* Otherwise, we have only some registers from switch_to() */
thread_regs = task_pt_regs(task);
gdb_regs[_R0] = thread_regs->ARM_r0;
gdb_regs[_R1] = thread_regs->ARM_r1;
gdb_regs[_R2] = thread_regs->ARM_r2;
gdb_regs[_R3] = thread_regs->ARM_r3;
gdb_regs[_R4] = thread_regs->ARM_r4;
gdb_regs[_R5] = thread_regs->ARM_r5;
gdb_regs[_R6] = thread_regs->ARM_r6;
gdb_regs[_R7] = thread_regs->ARM_r7;
gdb_regs[_R8] = thread_regs->ARM_r8;
gdb_regs[_R9] = thread_regs->ARM_r9;
gdb_regs[_R10] = thread_regs->ARM_r10;
gdb_regs[_FP] = thread_regs->ARM_fp;
gdb_regs[_IP] = thread_regs->ARM_ip;
gdb_regs[_SPT] = thread_regs->ARM_sp;
gdb_regs[_LR] = thread_regs->ARM_lr;
gdb_regs[_PC] = thread_regs->ARM_pc;
gdb_regs[_CPSR] = thread_regs->ARM_cpsr;
}
static int compiled_break;
int kgdb_arch_handle_exception(int exception_vector, int signo,
int err_code, char *remcom_in_buffer,
char *remcom_out_buffer,
struct pt_regs *linux_regs)
{
unsigned long addr;
char *ptr;
switch (remcom_in_buffer[0]) {
case 'D':
case 'k':
case 'c':
/*
* Try to read optional parameter, pc unchanged if no parm.
* If this was a compiled breakpoint, we need to move
* to the next instruction or we will just breakpoint
* over and over again.
*/
ptr = &remcom_in_buffer[1];
if (kgdb_hex2long(&ptr, &addr))
linux_regs->ARM_pc = addr;
else if (compiled_break == 1)
linux_regs->ARM_pc += 4;
compiled_break = 0;
return 0;
}
return -1;
}
static int kgdb_brk_fn(struct pt_regs *regs, unsigned int instr)
{
kgdb_handle_exception(1, SIGTRAP, 0, regs);
return 0;
}
static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int instr)
{
compiled_break = 1;
kgdb_handle_exception(1, SIGTRAP, 0, regs);
return 0;
}
static struct undef_hook kgdb_brkpt_hook = {
.instr_mask = 0xffffffff,
.instr_val = KGDB_BREAKINST,
.fn = kgdb_brk_fn
};
static struct undef_hook kgdb_compiled_brkpt_hook = {
.instr_mask = 0xffffffff,
.instr_val = KGDB_COMPILED_BREAK,
.fn = kgdb_compiled_brk_fn
};
/**
* kgdb_arch_init - Perform any architecture specific initalization.
*
* This function will handle the initalization of any architecture
* specific callbacks.
*/
int kgdb_arch_init(void)
{
register_undef_hook(&kgdb_brkpt_hook);
register_undef_hook(&kgdb_compiled_brkpt_hook);
return 0;
}
/**
* kgdb_arch_exit - Perform any architecture specific uninitalization.
*
* This function will handle the uninitalization of any architecture
* specific callbacks, for dynamic registration and unregistration.
*/
void kgdb_arch_exit(void)
{
unregister_undef_hook(&kgdb_brkpt_hook);
unregister_undef_hook(&kgdb_compiled_brkpt_hook);
}
/*
* Register our undef instruction hooks with ARM undef core.
* We regsiter a hook specifically looking for the KGB break inst
* and we handle the normal undef case within the do_undefinstr
* handler.
*/
struct kgdb_arch arch_kgdb_ops = {
#ifndef __ARMEB__
.gdb_bpt_instr = {0xfe, 0xde, 0xff, 0xe7}
#else /* ! __ARMEB__ */
.gdb_bpt_instr = {0xe7, 0xff, 0xde, 0xfe}
#endif
};
