linux/include/asm-sparc/kdebug.h

/* $Id: kdebug.h,v 1.11 2000/06/04 06:23:53 anton Exp $
 * kdebug.h:  Defines and definitions for debugging the Linux kernel
 *            under various kernel debuggers.
 *
 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 */
#ifndef _SPARC_KDEBUG_H
#define _SPARC_KDEBUG_H

#include <asm/openprom.h>
#include <asm/vaddrs.h>

/* Breakpoints are enter through trap table entry 126.  So in sparc assembly
 * if you want to drop into the debugger you do:
 *
 * t DEBUG_BP_TRAP
 */

#define DEBUG_BP_TRAP     126

#ifndef __ASSEMBLY__
/* The debug vector is passed in %o1 at boot time.  It is a pointer to
 * a structure in the debuggers address space.  Here is its format.
 */

typedef unsigned int (*debugger_funct)(void);

struct kernel_debug {
	/* First the entry point into the debugger.  You jump here
	 * to give control over to the debugger.
	 */
	unsigned long kdebug_entry;
	unsigned long kdebug_trapme;   /* Figure out later... */
	/* The following is the number of pages that the debugger has
	 * taken from to total pool.
	 */
	unsigned long *kdebug_stolen_pages;
	/* Ok, after you remap yourself and/or change the trap table
	 * from what you were left with at boot time you have to call
	 * this synchronization function so the debugger can check out
	 * what you have done.
	 */
	debugger_funct teach_debugger;
}; /* I think that is it... */

extern struct kernel_debug *linux_dbvec;

/* Use this macro in C-code to enter the debugger. */
static inline void sp_enter_debugger(void)
{
	__asm__ __volatile__("jmpl %0, %%o7\n\t"
			     "nop\n\t" : :
			     "r" (linux_dbvec) : "o7", "memory");
}

#define SP_ENTER_DEBUGGER do { \
	     if((linux_dbvec!=0) && ((*(short *)linux_dbvec)!=-1)) \
	       sp_enter_debugger(); \
		       } while(0)

#endif /* !(__ASSEMBLY__) */

/* Some nice offset defines for assembler code. */
#define KDEBUG_ENTRY_OFF    0x0
#define KDEBUG_DUNNO_OFF    0x4
#define KDEBUG_DUNNO2_OFF   0x8
#define KDEBUG_TEACH_OFF    0xc

#endif /* !(_SPARC_KDEBUG_H) */