diff options
Diffstat (limited to 'arch/mips/lib-32/watch.S')
| -rw-r--r-- | arch/mips/lib-32/watch.S | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/mips/lib-32/watch.S b/arch/mips/lib-32/watch.S new file mode 100644 index 00000000000..808b3af1a60 --- /dev/null +++ b/arch/mips/lib-32/watch.S @@ -0,0 +1,60 @@ +/* + * 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 by Ralf Baechle + */ +#include <asm/asm.h> +#include <asm/mipsregs.h> +#include <asm/regdef.h> + + .set noreorder +/* + * Parameter: a0 - logic address to watch + * Currently only KSEG0 addresses are allowed! + * a1 - set bit #1 to trap on load references + * bit #0 to trap on store references + * Results : none + */ + LEAF(__watch_set) + li t0, 0x80000000 + subu a0, t0 + ori a0, 7 + xori a0, 7 + or a0, a1 + mtc0 a0, CP0_WATCHLO + sw a0, watch_savelo + + 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) + lw t0, watch_savelo + jr ra + mtc0 t0, CP0_WATCHLO + END(__watch_reenable) + +/* + * Saved value of the c0_watchlo register for watch_reenable() + */ + .data +watch_savelo: .word 0 + .text |