LXR linux/arch/h8300/platform/h8s/ptrace

   1/*
   2 *  linux/arch/h8300/platform/h8s/ptrace_h8s.c
   3 *    ptrace cpu depend helper functions
   4 *
   5 *  Yoshinori Sato <ysato@users.sourceforge.jp>
   6 *
   7 * This file is subject to the terms and conditions of the GNU General
   8 * Public License.  See the file COPYING in the main directory of
   9 * this archive for more details.
  10 */
  11
  12#include <linux/linkage.h>
  13#include <linux/sched.h>
  14#include <linux/errno.h>
  15#include <asm/ptrace.h>
  16
  17#define CCR_MASK  0x6f
  18#define EXR_TRACE 0x80
  19
  20/* Mapping from PT_xxx to the stack offset at which the register is
  21   saved.  Notice that usp has no stack-slot and needs to be treated
  22   specially (see get_reg/put_reg below). */
  23static const int h8300_register_offset[] = {
  24        PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4),
  25        PT_REG(er5), PT_REG(er6), PT_REG(er0), PT_REG(orig_er0),
  26        PT_REG(ccr), PT_REG(pc),  0,           PT_REG(exr)
  27};
  28
  29/* read register */
  30long h8300_get_reg(struct task_struct *task, int regno)
  31{
  32        switch (regno) {
  33        case PT_USP:
  34                return task->thread.usp + sizeof(long)*2 + 2;
  35        case PT_CCR:
  36        case PT_EXR:
  37            return *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]);
  38        default:
  39            return *(unsigned long *)(task->thread.esp0 + h8300_register_offset[regno]);
  40        }
  41}
  42
  43/* write register */
  44int h8300_put_reg(struct task_struct *task, int regno, unsigned long data)
  45{
  46        unsigned short oldccr;
  47        switch (regno) {
  48        case PT_USP:
  49                task->thread.usp = data - sizeof(long)*2 - 2;
  50        case PT_CCR:
  51                oldccr = *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]);
  52                oldccr &= ~CCR_MASK;
  53                data &= CCR_MASK;
  54                data |= oldccr;
  55                *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]) = data;
  56                break;
  57        case PT_EXR:
  58                /* exr modify not support */
  59                return -EIO;
  60        default:
  61                *(unsigned long *)(task->thread.esp0 + h8300_register_offset[regno]) = data;
  62                break;
  63        }
  64        return 0;
  65}
  66
  67/* disable singlestep */
  68void user_disable_single_step(struct task_struct *child)
  69{
  70        *(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) &= ~EXR_TRACE;
  71}
  72
  73/* enable singlestep */
  74void user_enable_single_step(struct task_struct *child)
  75{
  76        *(unsigned short *)(child->thread.esp0 + h8300_register_offset[PT_EXR]) |= EXR_TRACE;
  77}
  78
  79asmlinkage void trace_trap(unsigned long bp)
  80{
  81        (void)bp;
  82        force_sig(SIGTRAP,current);
  83}
  84
  85