diff options
Diffstat (limited to 'arch/arm/kernel/kgdb.c')
| -rw-r--r-- | arch/arm/kernel/kgdb.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c new file mode 100644 index 00000000..778c2f70 --- /dev/null +++ b/arch/arm/kernel/kgdb.c @@ -0,0 +1,255 @@ +/* + * 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/irq.h> +#include <linux/kdebug.h> +#include <linux/kgdb.h> +#include <asm/traps.h> + +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = +{ + { "r0", 4, offsetof(struct pt_regs, ARM_r0)}, + { "r1", 4, offsetof(struct pt_regs, ARM_r1)}, + { "r2", 4, offsetof(struct pt_regs, ARM_r2)}, + { "r3", 4, offsetof(struct pt_regs, ARM_r3)}, + { "r4", 4, offsetof(struct pt_regs, ARM_r4)}, + { "r5", 4, offsetof(struct pt_regs, ARM_r5)}, + { "r6", 4, offsetof(struct pt_regs, ARM_r6)}, + { "r7", 4, offsetof(struct pt_regs, ARM_r7)}, + { "r8", 4, offsetof(struct pt_regs, ARM_r8)}, + { "r9", 4, offsetof(struct pt_regs, ARM_r9)}, + { "r10", 4, offsetof(struct pt_regs, ARM_r10)}, + { "fp", 4, offsetof(struct pt_regs, ARM_fp)}, + { "ip", 4, offsetof(struct pt_regs, ARM_ip)}, + { "sp", 4, offsetof(struct pt_regs, ARM_sp)}, + { "lr", 4, offsetof(struct pt_regs, ARM_lr)}, + { "pc", 4, offsetof(struct pt_regs, ARM_pc)}, + { "f0", 12, -1 }, + { "f1", 12, -1 }, + { "f2", 12, -1 }, + { "f3", 12, -1 }, + { "f4", 12, -1 }, + { "f5", 12, -1 }, + { "f6", 12, -1 }, + { "f7", 12, -1 }, + { "fps", 4, -1 }, + { "cpsr", 4, offsetof(struct pt_regs, ARM_cpsr)}, +}; + +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return NULL; + + if (dbg_reg_def[regno].offset != -1) + memcpy(mem, (void *)regs + dbg_reg_def[regno].offset, + dbg_reg_def[regno].size); + else + memset(mem, 0, dbg_reg_def[regno].size); + return dbg_reg_def[regno].name; +} + +int dbg_set_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return -EINVAL; + + if (dbg_reg_def[regno].offset != -1) + memcpy((void *)regs + dbg_reg_def[regno].offset, mem, + dbg_reg_def[regno].size); + return 0; +} + +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; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) +{ + regs->ARM_pc = pc; +} + +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 +}; + +static void kgdb_call_nmi_hook(void *ignored) +{ + kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); +} + +void kgdb_roundup_cpus(unsigned long flags) +{ + local_irq_enable(); + smp_call_function(kgdb_call_nmi_hook, NULL, 0); + local_irq_disable(); +} + +static int __kgdb_notify(struct die_args *args, unsigned long cmd) +{ + struct pt_regs *regs = args->regs; + + if (kgdb_handle_exception(1, args->signr, cmd, regs)) + return NOTIFY_DONE; + return NOTIFY_STOP; +} +static int +kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + ret = __kgdb_notify(ptr, cmd); + local_irq_restore(flags); + + return ret; +} + +static struct notifier_block kgdb_notifier = { + .notifier_call = kgdb_notify, + .priority = -INT_MAX, +}; + + +/** + * kgdb_arch_init - Perform any architecture specific initalization. + * + * This function will handle the initalization of any architecture + * specific callbacks. + */ +int kgdb_arch_init(void) +{ + int ret = register_die_notifier(&kgdb_notifier); + + if (ret != 0) + return ret; + + 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); + unregister_die_notifier(&kgdb_notifier); +} + +/* + * 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 +}; |