LXR linux/arch/powerpc/include/asm/probes.h

   1#ifndef _ASM_POWERPC_PROBES_H
   2#define _ASM_POWERPC_PROBES_H
   3#ifdef __KERNEL__
   4/*
   5 * Definitions common to probes files
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20 *
  21 * Copyright IBM Corporation, 2012
  22 */
  23#include <linux/types.h>
  24
  25typedef u32 ppc_opcode_t;
  26#define BREAKPOINT_INSTRUCTION  0x7fe00008      /* trap */
  27
  28/* Trap definitions per ISA */
  29#define IS_TW(instr)            (((instr) & 0xfc0007fe) == 0x7c000008)
  30#define IS_TD(instr)            (((instr) & 0xfc0007fe) == 0x7c000088)
  31#define IS_TDI(instr)           (((instr) & 0xfc000000) == 0x08000000)
  32#define IS_TWI(instr)           (((instr) & 0xfc000000) == 0x0c000000)
  33
  34#ifdef CONFIG_PPC64
  35#define is_trap(instr)          (IS_TW(instr) || IS_TD(instr) || \
  36                                IS_TWI(instr) || IS_TDI(instr))
  37#else
  38#define is_trap(instr)          (IS_TW(instr) || IS_TWI(instr))
  39#endif /* CONFIG_PPC64 */
  40
  41#ifdef CONFIG_PPC_ADV_DEBUG_REGS
  42#define MSR_SINGLESTEP  (MSR_DE)
  43#else
  44#define MSR_SINGLESTEP  (MSR_SE)
  45#endif
  46
  47/* Enable single stepping for the current task */
  48static inline void enable_single_step(struct pt_regs *regs)
  49{
  50        regs->msr |= MSR_SINGLESTEP;
  51#ifdef CONFIG_PPC_ADV_DEBUG_REGS
  52        /*
  53         * We turn off Critical Input Exception(CE) to ensure that the single
  54         * step will be for the instruction we have the probe on; if we don't,
  55         * it is possible we'd get the single step reported for CE.
  56         */
  57        regs->msr &= ~MSR_CE;
  58        mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
  59#ifdef CONFIG_PPC_47x
  60        isync();
  61#endif
  62#endif
  63}
  64
  65
  66#endif /* __KERNEL__ */
  67#endif  /* _ASM_POWERPC_PROBES_H */
  68