diff options
Diffstat (limited to 'arch/arm/kernel/kgdb.c')
| -rw-r--r-- | arch/arm/kernel/kgdb.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c new file mode 100644 index 0000000..ba8ccfe --- /dev/null +++ b/arch/arm/kernel/kgdb.c @@ -0,0 +1,199 @@ +/* + * 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 +}; |
