linux/arch/h8300/platform/h8300h/ptrace_h8300h.c
<<
>>
Prefs
   1/*
   2 *  linux/arch/h8300/platform/h8300h/ptrace_h8300h.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 <asm/ptrace.h>
  15
  16#define CCR_MASK 0x6f    /* mode/imask not set */
  17#define BREAKINST 0x5730 /* trapa #3 */
  18
  19/* Mapping from PT_xxx to the stack offset at which the register is
  20   saved.  Notice that usp has no stack-slot and needs to be treated
  21   specially (see get_reg/put_reg below). */
  22static const int h8300_register_offset[] = {
  23        PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4),
  24        PT_REG(er5), PT_REG(er6), PT_REG(er0), PT_REG(orig_er0),
  25        PT_REG(ccr), PT_REG(pc)
  26};
  27
  28/* read register */
  29long h8300_get_reg(struct task_struct *task, int regno)
  30{
  31        switch (regno) {
  32        case PT_USP:
  33                return task->thread.usp + sizeof(long)*2;
  34        case PT_CCR:
  35            return *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]);
  36        default:
  37            return *(unsigned long *)(task->thread.esp0 + h8300_register_offset[regno]);
  38        }
  39}
  40
  41/* write register */
  42int h8300_put_reg(struct task_struct *task, int regno, unsigned long data)
  43{
  44        unsigned short oldccr;
  45        switch (regno) {
  46        case PT_USP:
  47                task->thread.usp = data - sizeof(long)*2;
  48        case PT_CCR:
  49                oldccr = *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]);
  50                oldccr &= ~CCR_MASK;
  51                data &= CCR_MASK;
  52                data |= oldccr;
  53                *(unsigned short *)(task->thread.esp0 + h8300_register_offset[regno]) = data;
  54                break;
  55        default:
  56                *(unsigned long *)(task->thread.esp0 + h8300_register_offset[regno]) = data;
  57                break;
  58        }
  59        return 0;
  60}
  61
  62/* disable singlestep */
  63void user_disable_single_step(struct task_struct *child)
  64{
  65        if((long)child->thread.breakinfo.addr != -1L) {
  66                *child->thread.breakinfo.addr = child->thread.breakinfo.inst;
  67                child->thread.breakinfo.addr = (unsigned short *)-1L;
  68        }
  69}
  70
  71/* calculate next pc */
  72enum jump_type {none,    /* normal instruction */
  73                jabs,    /* absolute address jump */
  74                ind,     /* indirect address jump */
  75                ret,     /* return to subrutine */
  76                reg,     /* register indexed jump */
  77                relb,    /* pc relative jump (byte offset) */
  78                relw,    /* pc relative jump (word offset) */
  79               };
  80
  81/* opcode decode table define
  82   ptn: opcode pattern
  83   msk: opcode bitmask
  84   len: instruction length (<0 next table index)
  85   jmp: jump operation mode */
  86struct optable {
  87        unsigned char bitpattern;
  88        unsigned char bitmask;
  89        signed char length;
  90        signed char type;
  91} __attribute__((aligned(1),packed));
  92
  93#define OPTABLE(ptn,msk,len,jmp)   \
  94        {                          \
  95                .bitpattern = ptn, \
  96                .bitmask    = msk, \
  97                .length     = len, \
  98                .type       = jmp, \
  99        }
 100
 101static const struct optable optable_0[] = {
 102        OPTABLE(0x00,0xff, 1,none), /* 0x00 */
 103        OPTABLE(0x01,0xff,-1,none), /* 0x01 */
 104        OPTABLE(0x02,0xfe, 1,none), /* 0x02-0x03 */
 105        OPTABLE(0x04,0xee, 1,none), /* 0x04-0x05/0x14-0x15 */
 106        OPTABLE(0x06,0xfe, 1,none), /* 0x06-0x07 */
 107        OPTABLE(0x08,0xea, 1,none), /* 0x08-0x09/0x0c-0x0d/0x18-0x19/0x1c-0x1d */
 108        OPTABLE(0x0a,0xee, 1,none), /* 0x0a-0x0b/0x1a-0x1b */
 109        OPTABLE(0x0e,0xee, 1,none), /* 0x0e-0x0f/0x1e-0x1f */
 110        OPTABLE(0x10,0xfc, 1,none), /* 0x10-0x13 */
 111        OPTABLE(0x16,0xfe, 1,none), /* 0x16-0x17 */
 112        OPTABLE(0x20,0xe0, 1,none), /* 0x20-0x3f */
 113        OPTABLE(0x40,0xf0, 1,relb), /* 0x40-0x4f */
 114        OPTABLE(0x50,0xfc, 1,none), /* 0x50-0x53 */
 115        OPTABLE(0x54,0xfd, 1,ret ), /* 0x54/0x56 */
 116        OPTABLE(0x55,0xff, 1,relb), /* 0x55 */
 117        OPTABLE(0x57,0xff, 1,none), /* 0x57 */
 118        OPTABLE(0x58,0xfb, 2,relw), /* 0x58/0x5c */
 119        OPTABLE(0x59,0xfb, 1,reg ), /* 0x59/0x5b */
 120        OPTABLE(0x5a,0xfb, 2,jabs), /* 0x5a/0x5e */
 121        OPTABLE(0x5b,0xfb, 2,ind ), /* 0x5b/0x5f */
 122        OPTABLE(0x60,0xe8, 1,none), /* 0x60-0x67/0x70-0x77 */
 123        OPTABLE(0x68,0xfa, 1,none), /* 0x68-0x69/0x6c-0x6d */
 124        OPTABLE(0x6a,0xfe,-2,none), /* 0x6a-0x6b */
 125        OPTABLE(0x6e,0xfe, 2,none), /* 0x6e-0x6f */
 126        OPTABLE(0x78,0xff, 4,none), /* 0x78 */
 127        OPTABLE(0x79,0xff, 2,none), /* 0x79 */
 128        OPTABLE(0x7a,0xff, 3,none), /* 0x7a */
 129        OPTABLE(0x7b,0xff, 2,none), /* 0x7b */
 130        OPTABLE(0x7c,0xfc, 2,none), /* 0x7c-0x7f */
 131        OPTABLE(0x80,0x80, 1,none), /* 0x80-0xff */
 132};
 133
 134static const struct optable optable_1[] = {
 135        OPTABLE(0x00,0xff,-3,none), /* 0x0100 */
 136        OPTABLE(0x40,0xf0,-3,none), /* 0x0140-0x14f */
 137        OPTABLE(0x80,0xf0, 1,none), /* 0x0180-0x018f */
 138        OPTABLE(0xc0,0xc0, 2,none), /* 0x01c0-0x01ff */
 139};
 140
 141static const struct optable optable_2[] = {
 142        OPTABLE(0x00,0x20, 2,none), /* 0x6a0?/0x6a8?/0x6b0?/0x6b8? */
 143        OPTABLE(0x20,0x20, 3,none), /* 0x6a2?/0x6aa?/0x6b2?/0x6ba? */
 144};
 145
 146static const struct optable optable_3[] = {
 147        OPTABLE(0x69,0xfb, 2,none), /* 0x010069/0x01006d/014069/0x01406d */
 148        OPTABLE(0x6b,0xff,-4,none), /* 0x01006b/0x01406b */
 149        OPTABLE(0x6f,0xff, 3,none), /* 0x01006f/0x01406f */
 150        OPTABLE(0x78,0xff, 5,none), /* 0x010078/0x014078 */
 151};
 152
 153static const struct optable optable_4[] = {
 154        OPTABLE(0x00,0x78, 3,none), /* 0x0100690?/0x01006d0?/0140690/0x01406d0?/0x0100698?/0x01006d8?/0140698?/0x01406d8? */
 155        OPTABLE(0x20,0x78, 4,none), /* 0x0100692?/0x01006d2?/0140692/0x01406d2?/0x010069a?/0x01006da?/014069a?/0x01406da? */
 156};
 157
 158static const struct optables_list {
 159        const struct optable *ptr;
 160        int size;
 161} optables[] = {
 162#define OPTABLES(no)                                                   \
 163        {                                                              \
 164                .ptr  = optable_##no,                                  \
 165                .size = sizeof(optable_##no) / sizeof(struct optable), \
 166        }
 167        OPTABLES(0),
 168        OPTABLES(1),
 169        OPTABLES(2),
 170        OPTABLES(3),
 171        OPTABLES(4),
 172
 173};
 174
 175const unsigned char condmask[] = {
 176        0x00,0x40,0x01,0x04,0x02,0x08,0x10,0x20
 177};
 178
 179static int isbranch(struct task_struct *task,int reson)
 180{
 181        unsigned char cond = h8300_get_reg(task, PT_CCR);
 182        /* encode complex conditions */
 183        /* B4: N^V
 184           B5: Z|(N^V)
 185           B6: C|Z */
 186        __asm__("bld #3,%w0\n\t"
 187                "bxor #1,%w0\n\t"
 188                "bst #4,%w0\n\t"
 189                "bor #2,%w0\n\t"
 190                "bst #5,%w0\n\t"
 191                "bld #2,%w0\n\t"
 192                "bor #0,%w0\n\t"
 193                "bst #6,%w0\n\t"
 194                :"=&r"(cond)::"cc");
 195        cond &= condmask[reson >> 1];
 196        if (!(reson & 1))
 197                return cond == 0;
 198        else
 199                return cond != 0;
 200}
 201
 202static unsigned short *getnextpc(struct task_struct *child, unsigned short *pc)
 203{
 204        const struct optable *op;
 205        unsigned char *fetch_p;
 206        unsigned char inst;
 207        unsigned long addr;
 208        unsigned long *sp;
 209        int op_len,regno;
 210        op = optables[0].ptr;
 211        op_len = optables[0].size;
 212        fetch_p = (unsigned char *)pc;
 213        inst = *fetch_p++;
 214        do {
 215                if ((inst & op->bitmask) == op->bitpattern) {
 216                        if (op->length < 0) {
 217                                op = optables[-op->length].ptr;
 218                                op_len = optables[-op->length].size + 1;
 219                                inst = *fetch_p++;
 220                        } else {
 221                                switch (op->type) {
 222                                case none:
 223                                        return pc + op->length;
 224                                case jabs:
 225                                        addr = *(unsigned long *)pc;
 226                                        return (unsigned short *)(addr & 0x00ffffff);
 227                                case ind:
 228                                        addr = *pc & 0xff;
 229                                        return (unsigned short *)(*(unsigned long *)addr);
 230                                case ret:
 231                                        sp = (unsigned long *)h8300_get_reg(child, PT_USP);
 232                                        /* user stack frames
 233                                           |   er0  | temporary saved
 234                                           +--------+
 235                                           |   exp  | exception stack frames
 236                                           +--------+
 237                                           | ret pc | userspace return address
 238                                        */
 239                                        return (unsigned short *)(*(sp+2) & 0x00ffffff);
 240                                case reg:
 241                                        regno = (*pc >> 4) & 0x07;
 242                                        if (regno == 0)
 243                                                addr = h8300_get_reg(child, PT_ER0);
 244                                        else
 245                                                addr = h8300_get_reg(child, regno-1+PT_ER1);
 246                                        return (unsigned short *)addr;
 247                                case relb:
 248                                        if (inst == 0x55 || isbranch(child,inst & 0x0f))
 249                                                pc = (unsigned short *)((unsigned long)pc +
 250                                                                       ((signed char)(*fetch_p)));
 251                                        return pc+1; /* skip myself */
 252                                case relw:
 253                                        if (inst == 0x5c || isbranch(child,(*fetch_p & 0xf0) >> 4))
 254                                                pc = (unsigned short *)((unsigned long)pc +
 255                                                                       ((signed short)(*(pc+1))));
 256                                        return pc+2; /* skip myself */
 257                                }
 258                        }
 259                } else
 260                        op++;
 261        } while(--op_len > 0);
 262        return NULL;
 263}
 264
 265/* Set breakpoint(s) to simulate a single step from the current PC.  */
 266
 267void user_enable_single_step(struct task_struct *child)
 268{
 269        unsigned short *nextpc;
 270        nextpc = getnextpc(child,(unsigned short *)h8300_get_reg(child, PT_PC));
 271        child->thread.breakinfo.addr = nextpc;
 272        child->thread.breakinfo.inst = *nextpc;
 273        *nextpc = BREAKINST;
 274}
 275
 276asmlinkage void trace_trap(unsigned long bp)
 277{
 278        if ((unsigned long)current->thread.breakinfo.addr == bp) {
 279                user_disable_single_step(current);
 280                force_sig(SIGTRAP,current);
 281        } else
 282                force_sig(SIGILL,current);
 283}
 284
 285
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.