xtensa: add trap_set_handler function

trap_set_handler sets new C-handler in the exception table and returns
previous handler.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
This commit is contained in:
Max Filippov 2012-11-19 08:30:15 +04:00 committed by Chris Zankel
parent c622b29d1f
commit 28570e8dac
2 changed files with 34 additions and 0 deletions

View file

@ -0,0 +1,23 @@
/*
* arch/xtensa/include/asm/traps.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2012 Tensilica Inc.
*/
#ifndef _XTENSA_TRAPS_H
#define _XTENSA_TRAPS_H
#include <asm/ptrace.h>
/*
* handler must be either of the following:
* void (*)(struct pt_regs *regs);
* void (*)(struct pt_regs *regs, unsigned long exccause);
*/
extern void * __init trap_set_handler(int cause, void *handler);
extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
#endif /* _XTENSA_TRAPS_H */

View file

@ -293,6 +293,17 @@ do_debug(struct pt_regs *regs)
}
/* Set exception C handler - for temporary use when probing exceptions */
void * __init trap_set_handler(int cause, void *handler)
{
unsigned long *entry = &exc_table[EXC_TABLE_DEFAULT / 4 + cause];
void *previous = (void *)*entry;
*entry = (unsigned long)handler;
return previous;
}
/*
* Initialize dispatch tables.
*