root/arch/powerpc/include/asm/probes.h

INCLUDED FROM

DEFINITIONS

1. enable_single_step

   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 
  12 typedef 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 */
  35 static inline void enable_single_step(struct pt_regs *regs)
  36 {
  37         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->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 */