src/target/mips_ejtag.c

   1 /***************************************************************************
   2  *   Copyright (C) 2008 by Spencer Oliver                                  *
   3  *   spen@spen-soft.co.uk                                                  *
   4  *                                                                         *
   5  *   Copyright (C) 2008 by David T.L. Wong                                 *
   6  *                                                                         *
   7  *   Copyright (C) 2009 by David N. Claffey <dnclaffey@gmail.com>          *
   8  *                                                                         *
   9  *   This program is free software; you can redistribute it and/or modify  *
  10  *   it under the terms of the GNU General Public License as published by  *
  11  *   the Free Software Foundation; either version 2 of the License, or     *
  12  *   (at your option) any later version.                                   *
  13  *                                                                         *
  14  *   This program is distributed in the hope that it will be useful,       *
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  17  *   GNU General Public License for more details.                          *
  18  *                                                                         *
  19  *   You should have received a copy of the GNU General Public License     *
  20  *   along with this program; if not, write to the                         *
  21  *   Free Software Foundation, Inc.,                                       *
  22  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  23  ***************************************************************************/
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #endif
  27
  28 #include "mips32.h"
  29 #include "mips_ejtag.h"
  30
  31 int mips_ejtag_set_instr(struct mips_ejtag *ejtag_info, int new_instr)
  32 {
  33         struct jtag_tap *tap;
  34
  35         tap = ejtag_info->tap;
  36         if (tap == NULL)
  37                 return ERROR_FAIL;
  38
  39         if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != (uint32_t)new_instr)
  40         {
  41                 struct scan_field field;
  42                 uint8_t t[4];
  43
  44                 field.num_bits = tap->ir_length;
  45                 field.out_value = t;
  46                 buf_set_u32(t, 0, field.num_bits, new_instr);
  47                 field.in_value = NULL;
  48
  49                 jtag_add_ir_scan(tap, &field, TAP_IDLE);
  50         }
  51
  52         return ERROR_OK;
  53 }
  54
  55 int mips_ejtag_get_idcode(struct mips_ejtag *ejtag_info, uint32_t *idcode)
  56 {
  57         struct scan_field field;
  58
  59         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IDCODE);
  60
  61         field.num_bits = 32;
  62         field.out_value = NULL;
  63         field.in_value = (void*)idcode;
  64
  65         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  66
  67         int retval;
  68         if ((retval = jtag_execute_queue()) != ERROR_OK)
  69         {
  70                 LOG_ERROR("register read failed");
  71                 return retval;
  72         }
  73         return ERROR_OK;
  74 }
  75
  76 static int mips_ejtag_get_impcode(struct mips_ejtag *ejtag_info, uint32_t *impcode)
  77 {
  78         struct scan_field field;
  79
  80         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE);
  81
  82         field.num_bits = 32;
  83         field.out_value = NULL;
  84         field.in_value = (void*)impcode;
  85
  86         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  87
  88         int retval;
  89         if ((retval = jtag_execute_queue()) != ERROR_OK)
  90         {
  91                 LOG_ERROR("register read failed");
  92                 return retval;
  93         }
  94         return ERROR_OK;
  95 }
  96
  97 int mips_ejtag_drscan_32(struct mips_ejtag *ejtag_info, uint32_t *data)
  98 {
  99         struct jtag_tap *tap;
 100         tap  = ejtag_info->tap;
 101
 102         if (tap == NULL)
 103                 return ERROR_FAIL;
 104         struct scan_field field;
 105         uint8_t t[4], r[4];
 106         int retval;
 107
 108         field.num_bits = 32;
 109         field.out_value = t;
 110         buf_set_u32(t, 0, field.num_bits, *data);
 111         field.in_value = r;
 112
 113         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 114
 115         if ((retval = jtag_execute_queue()) != ERROR_OK)
 116         {
 117                 LOG_ERROR("register read failed");
 118                 return retval;
 119         }
 120
 121         *data = buf_get_u32(field.in_value, 0, 32);
 122
 123         keep_alive();
 124
 125         return ERROR_OK;
 126 }
 127
 128 int mips_ejtag_drscan_8(struct mips_ejtag *ejtag_info, uint32_t *data)
 129 {
 130         struct jtag_tap *tap;
 131         tap  = ejtag_info->tap;
 132
 133         if (tap == NULL)
 134                 return ERROR_FAIL;
 135         struct scan_field field;
 136         uint8_t t[4] = {0, 0, 0, 0}, r[4];
 137         int retval;
 138
 139         field.num_bits = 8;
 140         field.out_value = t;
 141         buf_set_u32(t, 0, field.num_bits, *data);
 142         field.in_value = r;
 143
 144         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 145
 146         if ((retval = jtag_execute_queue()) != ERROR_OK)
 147         {
 148                 LOG_ERROR("register read failed");
 149                 return retval;
 150         }
 151
 152         *data = buf_get_u32(field.in_value, 0, 32);
 153
 154         keep_alive();
 155
 156         return ERROR_OK;
 157 }
 158
 159 static int mips_ejtag_step_enable(struct mips_ejtag *ejtag_info)
 160 {
 161         static const uint32_t code[] = {
 162                         MIPS32_MTC0(1,31,0),                    /* move $1 to COP0 DeSave */
 163                         MIPS32_MFC0(1,23,0),                    /* move COP0 Debug to $1 */
 164                         MIPS32_ORI(1,1,0x0100),                 /* set SSt bit in debug reg */
 165                         MIPS32_MTC0(1,23,0),                    /* move $1 to COP0 Debug */
 166                         MIPS32_B(NEG16(5)),
 167                         MIPS32_MFC0(1,31,0),                    /* move COP0 DeSave to $1 */
 168         };
 169
 170         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 171                 0, NULL, 0, NULL, 1);
 172
 173         return ERROR_OK;
 174 }
 175
 176 static int mips_ejtag_step_disable(struct mips_ejtag *ejtag_info)
 177 {
 178         static const uint32_t code[] = {
 179                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 180                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 181                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 182                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 183                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 184                         MIPS32_MFC0(1,23,0),                                                    /* move COP0 Debug to $1 */
 185                         MIPS32_LUI(2,0xFFFF),                                                   /* $2 = 0xfffffeff */
 186                         MIPS32_ORI(2,2,0xFEFF),
 187                         MIPS32_AND(1,1,2),
 188                         MIPS32_MTC0(1,23,0),                                                    /* move $1 to COP0 Debug */
 189                         MIPS32_LW(2,0,15),
 190                         MIPS32_LW(1,0,15),
 191                         MIPS32_B(NEG16(13)),
 192                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 193         };
 194
 195         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 196                 0, NULL, 0, NULL, 1);
 197
 198         return ERROR_OK;
 199 }
 200
 201 int mips_ejtag_config_step(struct mips_ejtag *ejtag_info, int enable_step)
 202 {
 203         if (enable_step)
 204                 return mips_ejtag_step_enable(ejtag_info);
 205         return mips_ejtag_step_disable(ejtag_info);
 206 }
 207
 208 int mips_ejtag_enter_debug(struct mips_ejtag *ejtag_info)
 209 {
 210         uint32_t ejtag_ctrl;
 211         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
 212
 213         /* set debug break bit */
 214         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 215         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 216
 217         /* break bit will be cleared by hardware */
 218         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 219         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 220         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 221         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0)
 222                 LOG_DEBUG("Failed to enter Debug Mode!");
 223
 224         return ERROR_OK;
 225 }
 226
 227 int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 228 {
 229         uint32_t inst;
 230         inst = MIPS32_DRET;
 231
 232         /* execute our dret instruction */
 233         mips32_pracc_exec(ejtag_info, 1, &inst, 0, NULL, 0, NULL, 0);
 234
 235         return ERROR_OK;
 236 }
 237
 238 int mips_ejtag_read_debug(struct mips_ejtag *ejtag_info, uint32_t* debug_reg)
 239 {
 240         /* read ejtag ECR */
 241         static const uint32_t code[] = {
 242                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 243                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 244                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 245                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 246                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 247                         MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $1 = MIPS32_PRACC_PARAM_OUT */
 248                         MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_OUT)),
 249                         MIPS32_MFC0(2,23,0),                                                    /* move COP0 Debug to $2 */
 250                         MIPS32_SW(2,0,1),
 251                         MIPS32_LW(2,0,15),
 252                         MIPS32_LW(1,0,15),
 253                         MIPS32_B(NEG16(12)),
 254                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 255         };
 256
 257         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 258                 0, NULL, 1, debug_reg, 1);
 259
 260         return ERROR_OK;
 261 }
 262
 263 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 264 {
 265         uint32_t ejtag_version;
 266
 267         mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 268         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 269
 270         /* get ejtag version */
 271         ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 272
 273         switch (ejtag_version)
 274         {
 275                 case 0:
 276                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 277                         break;
 278                 case 1:
 279                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 280                         break;
 281                 case 2:
 282                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 283                         break;
 284                 case 3:
 285                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 286                         break;
 287                 default:
 288                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 289                         break;
 290         }
 291         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 292                 ejtag_info->impcode & EJTAG_IMP_R3K ? " R3k" : " R4k",
 293                 ejtag_info->impcode & EJTAG_IMP_DINT ? " DINT" : "",
 294                 ejtag_info->impcode & (1 << 22) ? " ASID_8" : "",
 295                 ejtag_info->impcode & (1 << 21) ? " ASID_6" : "",
 296                 ejtag_info->impcode & EJTAG_IMP_MIPS16 ? " MIPS16" : "",
 297                 ejtag_info->impcode & EJTAG_IMP_NODMA ? " noDMA" : " DMA",
 298                 ejtag_info->impcode & EJTAG_DCR_MIPS64  ? " MIPS64" : " MIPS32");
 299
 300         if ((ejtag_info->impcode & EJTAG_IMP_NODMA) == 0)
 301                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 302
 303         /* set initial state for ejtag control reg */
 304         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 305         ejtag_info->fast_access_save = -1;
 306
 307         return ERROR_OK;
 308 }
 309
 310 int mips_ejtag_fastdata_scan(struct mips_ejtag *ejtag_info, int write_t, uint32_t *data)
 311 {
 312         struct jtag_tap *tap;
 313         tap = ejtag_info->tap;
 314
 315         if (tap == NULL)
 316                 return ERROR_FAIL;
 317
 318         struct scan_field fields[2];
 319         uint8_t spracc = 0;
 320         uint8_t t[4] = {0, 0, 0, 0};
 321
 322         /* fastdata 1-bit register */
 323         fields[0].num_bits = 1;
 324         fields[0].out_value = &spracc;
 325         fields[0].in_value = NULL;
 326
 327         /* processor access data register 32 bit */
 328         fields[1].num_bits = 32;
 329         fields[1].out_value = t;
 330
 331         if (write_t)
 332         {
 333                 fields[1].in_value = NULL;
 334                 buf_set_u32(t, 0, 32, *data);
 335         }
 336         else
 337         {
 338                 fields[1].in_value = (uint8_t *) data;
 339         }
 340
 341         jtag_add_dr_scan(tap, 2, fields, TAP_IDLE);
 342         keep_alive();
 343
 344         return ERROR_OK;
 345 }