[AVR32] Clean up exception handling code

  * Use generic BUG() handling
  * Remove some useless debug statements
  * Use a common function _exception() to send signals or oops when
    an exception can't be handled. This makes sure init doesn't
    enter an infinite exception loop as well. Borrowed from powerpc.
  * Add some basic exception tracing support to the page fault code.
  * Rework dump_stack(), show_regs() and friends and move everything
    into process.c
  * Print information about configuration options and chip type when
    oopsing

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>

3 files changed, 45 insertions, 24 deletions

diff --git a/include/asm-avr32/bug.h b/include/asm-avr32/bug.h
index 521766b..afdcd79 100644
--- a/include/asm-avr32/bug.h
+++ b/include/asm-avr32/bug.h
@@ -18,27 +18,53 @@
 
 #ifdef CONFIG_DEBUG_BUGVERBOSE
 
-#define BUG()								\
-	do {								\
-		asm volatile(".hword	%0\n\t"				\
-			     ".hword	%1\n\t"				\
-			     ".long	%2"				\
-			     :						\
-			     : "n"(AVR32_BUG_OPCODE),			\
-			       "i"(__LINE__), "X"(__FILE__));		\
-	} while (0)
+#define _BUG_OR_WARN(flags)						\
+	asm volatile(							\
+		"1:	.hword	%0\n"					\
+		"	.section __bug_table,\"a\",@progbits\n"		\
+		"2:	.long	1b\n"					\
+		"	.long	%1\n"					\
+		"	.short	%2\n"					\
+		"	.short	%3\n"					\
+		"	.org	2b + %4\n"				\
+		"	.previous"					\
+		:							\
+		: "i"(AVR32_BUG_OPCODE), "i"(__FILE__),			\
+		  "i"(__LINE__), "i"(flags),				\
+		  "i"(sizeof(struct bug_entry)))
 
 #else
 
+#define _BUG_OR_WARN(flags)						\
+	asm volatile(							\
+		"1:	.hword	%0\n"					\
+		"	.section __bug_table,\"a\",@progbits\n"		\
+		"2:	.long	1b\n"					\
+		"	.short	%1\n"					\
+		"	.org	2b + %2\n"				\
+		"	.previous"					\
+		:							\
+		: "i"(AVR32_BUG_OPCODE), "i"(flags),			\
+		  "i"(sizeof(struct bug_entry)))
+
+#endif /* CONFIG_DEBUG_BUGVERBOSE */
+
 #define BUG()								\
 	do {								\
-		asm volatile(".hword	%0\n\t"				\
-			     : : "n"(AVR32_BUG_OPCODE));		\
+		_BUG_OR_WARN(0);					\
+		for (;;);						\
 	} while (0)
 
-#endif /* CONFIG_DEBUG_BUGVERBOSE */
+#define WARN_ON(condition)							\
+	({								\
+		typeof(condition) __ret_warn_on = (condition);		\
+		if (unlikely(__ret_warn_on))				\
+			_BUG_OR_WARN(BUGFLAG_WARNING);			\
+		unlikely(__ret_warn_on);				\
+	})
 
 #define HAVE_ARCH_BUG
+#define HAVE_ARCH_WARN_ON
 
 #endif /* CONFIG_BUG */
 
diff --git a/include/asm-avr32/processor.h b/include/asm-avr32/processor.h
index cbb89cc..6a64833 100644
--- a/include/asm-avr32/processor.h
+++ b/include/asm-avr32/processor.h
@@ -134,10 +134,10 @@ extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 #define thread_saved_pc(tsk)    ((tsk)->thread.cpu_context.pc)
 
 struct pt_regs;
-void show_trace(struct task_struct *task, unsigned long *stack,
-		struct pt_regs *regs);
-
 extern unsigned long get_wchan(struct task_struct *p);
+extern void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl);
+extern void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp,
+			       struct pt_regs *regs, const char *log_lvl);
 
 #define KSTK_EIP(tsk)	((tsk)->thread.cpu_context.pc)
 #define KSTK_ESP(tsk)	((tsk)->thread.cpu_context.ksp)
diff --git a/include/asm-avr32/system.h b/include/asm-avr32/system.h
index ac596058..a8236ba 100644
--- a/include/asm-avr32/system.h
+++ b/include/asm-avr32/system.h
@@ -9,6 +9,7 @@
 #define __ASM_AVR32_SYSTEM_H
 
 #include <linux/compiler.h>
+#include <linux/linkage.h>
 #include <linux/types.h>
 
 #include <asm/ptrace.h>
@@ -140,15 +141,9 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
 				   sizeof(*(ptr))))
 
 struct pt_regs;
-extern void __die(const char *, struct pt_regs *, unsigned long,
-		  const char *, const char *, unsigned long);
-extern void __die_if_kernel(const char *, struct pt_regs *, unsigned long,
-			    const char *, const char *, unsigned long);
-
-#define die(msg, regs, err)					\
-	__die(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)
-#define die_if_kernel(msg, regs, err)					\
-	__die_if_kernel(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__)
+void NORET_TYPE die(const char *str, struct pt_regs *regs, long err);
+void _exception(long signr, struct pt_regs *regs, int code,
+		unsigned long addr);
 
 #define arch_align_stack(x)	(x)