linux-sg2042/arch/mips/lib-64/watch.S

58 lines
1.2 KiB
ArmAsm

/*
* 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.
*
* Kernel debug stuff to use the Watch registers.
* Useful to find stack overflows, dangling pointers etc.
*
* Copyright (C) 1995, 1996, 1999, 2001 by Ralf Baechle
*/
#include <asm/asm.h>
#include <asm/mipsregs.h>
#include <asm/regdef.h>
.set noreorder
/*
* Parameter: a0 - physical address to watch
* a1 - set bit #1 to trap on load references
* bit #0 to trap on store references
* Results : none
*/
LEAF(__watch_set)
ori a0, 7
xori a0, 7
or a0, a1
mtc0 a0, CP0_WATCHLO
sd a0, watch_savelo
dsrl32 a0, a0, 0
jr ra
mtc0 zero, CP0_WATCHHI
END(__watch_set)
/*
* Parameter: none
* Results : none
*/
LEAF(__watch_clear)
jr ra
mtc0 zero, CP0_WATCHLO
END(__watch_clear)
/*
* Parameter: none
* Results : none
*/
LEAF(__watch_reenable)
ld t0, watch_savelo
jr ra
mtc0 t0, CP0_WATCHLO
END(__watch_reenable)
/*
* Saved value of the c0_watchlo register for watch_reenable()
*/
.local watch_savelo
.comm watch_savelo, 8, 8