arm,kgdb: Add ability to trap into debugger on notify_die

[sfrench/cifs-2.6.git] / arch / arm / kernel / kgdb.c

diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index c868a8864117bbf0f3330ebd80150f263a3200ed..778c2f7024ff57304227ce67665e749f39b05fc7 100644 (file)
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -10,57 +10,62 @@
  *           Deepak Saxena <dsaxena@plexity.net>
  */
 #include <linux/irq.h>
+#include <linux/kdebug.h>
 #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)
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
 {
-       int regno;
-
-       /* Initialize all to zero. */
-       for (regno = 0; regno < GDB_MAX_REGS; regno++)
-               gdb_regs[regno] = 0;
+       { "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)},
+};
 
-       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;
+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;
 }
 
-/* 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)
+int dbg_set_reg(int regno, void *mem, struct pt_regs *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];
+       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
@@ -176,6 +181,33 @@ void kgdb_roundup_cpus(unsigned long flags)
        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.
  *
@@ -184,6 +216,11 @@ void kgdb_roundup_cpus(unsigned long flags)
  */
 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);
 
@@ -200,6 +237,7 @@ void kgdb_arch_exit(void)
 {
        unregister_undef_hook(&kgdb_brkpt_hook);
        unregister_undef_hook(&kgdb_compiled_brkpt_hook);
+       unregister_die_notifier(&kgdb_notifier);
 }
 
 /*