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

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2#ifndef _ASM_POWERPC_PROBES_H
   3#define _ASM_POWERPC_PROBES_H
   4#ifdef __KERNEL__
   5/*
   6 * Definitions common to probes files
   7 *
   8 * Copyright IBM Corporation, 2012
   9 */
  10#include <linux/types.h>
  11
  12typedef u32 ppc_opcode_t;
  13#define BREAKPOINT_INSTRUCTION  0x7fe00008      /* trap */
  14
  15/* Trap definitions per ISA */
  16#define IS_TW(instr)            (((instr) & 0xfc0007fe) == 0x7c000008)
  17#define IS_TD(instr)            (((instr) & 0xfc0007fe) == 0x7c000088)
  18#define IS_TDI(instr)           (((instr) & 0xfc000000) == 0x08000000)
  19#define IS_TWI(instr)           (((instr) & 0xfc000000) == 0x0c000000)
  20
  21#ifdef CONFIG_PPC64
  22#define is_trap(instr)          (IS_TW(instr) || IS_TD(instr) || \
  23                                IS_TWI(instr) || IS_TDI(instr))
  24#else
  25#define is_trap(instr)          (IS_TW(instr) || IS_TWI(instr))
  26#endif /* CONFIG_PPC64 */
  27
  28#ifdef CONFIG_PPC_ADV_DEBUG_REGS
  29#define MSR_SINGLESTEP  (MSR_DE)
  30#else
  31#define MSR_SINGLESTEP  (MSR_SE)
  32#endif
  33
  34/* Enable single stepping for the current task */
  35static inline void enable_single_step(struct pt_regs *regs)
  36{
  37        regs_set_return_msr(regs, regs->msr | MSR_SINGLESTEP);
  38#ifdef CONFIG_PPC_ADV_DEBUG_REGS
  39        /*
  40         * We turn off Critical Input Exception(CE) to ensure that the single
  41         * step will be for the instruction we have the probe on; if we don't,
  42         * it is possible we'd get the single step reported for CE.
  43         */
  44        regs_set_return_msr(regs, regs->msr & ~MSR_CE);
  45        mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
  46#ifdef CONFIG_PPC_47x
  47        isync();
  48#endif
  49#endif
  50}
  51
  52
  53#endif /* __KERNEL__ */
  54#endif  /* _ASM_POWERPC_PROBES_H */
  55