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         if (jtag_execute_queue() != ERROR_OK)
  68         {
  69                 LOG_ERROR("register read failed");
  70         }
  71
  72         return ERROR_OK;
  73 }
  74
  75 static int mips_ejtag_get_impcode(struct mips_ejtag *ejtag_info, uint32_t *impcode)
  76 {
  77         struct scan_field field;
  78
  79         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE);
  80
  81         field.num_bits = 32;
  82         field.out_value = NULL;
  83         field.in_value = (void*)impcode;
  84
  85         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  86
  87         if (jtag_execute_queue() != ERROR_OK)
  88         {
  89                 LOG_ERROR("register read failed");
  90         }
  91
  92         return ERROR_OK;
  93 }
  94
  95 int mips_ejtag_drscan_32(struct mips_ejtag *ejtag_info, uint32_t *data)
  96 {
  97         struct jtag_tap *tap;
  98         tap  = ejtag_info->tap;
  99
 100         if (tap == NULL)
 101                 return ERROR_FAIL;
 102         struct scan_field field;
 103         uint8_t t[4], r[4];
 104         int retval;
 105
 106         field.num_bits = 32;
 107         field.out_value = t;
 108         buf_set_u32(t, 0, field.num_bits, *data);
 109         field.in_value = r;
 110
 111         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 112
 113         if ((retval = jtag_execute_queue()) != ERROR_OK)
 114         {
 115                 LOG_ERROR("register read failed");
 116                 return retval;
 117         }
 118
 119         *data = buf_get_u32(field.in_value, 0, 32);
 120
 121         keep_alive();
 122
 123         return ERROR_OK;
 124 }
 125
 126 int mips_ejtag_drscan_8(struct mips_ejtag *ejtag_info, uint32_t *data)
 127 {
 128         struct jtag_tap *tap;
 129         tap  = ejtag_info->tap;
 130
 131         if (tap == NULL)
 132                 return ERROR_FAIL;
 133         struct scan_field field;
 134         uint8_t t[4] = {0, 0, 0, 0}, r[4];
 135         int retval;
 136
 137         field.num_bits = 8;
 138         field.out_value = t;
 139         buf_set_u32(t, 0, field.num_bits, *data);
 140         field.in_value = r;
 141
 142         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 143
 144         if ((retval = jtag_execute_queue()) != ERROR_OK)
 145         {
 146                 LOG_ERROR("register read failed");
 147                 return retval;
 148         }
 149
 150         *data = buf_get_u32(field.in_value, 0, 32);
 151
 152         keep_alive();
 153
 154         return ERROR_OK;
 155 }
 156
 157 static int mips_ejtag_step_enable(struct mips_ejtag *ejtag_info)
 158 {
 159         static const uint32_t code[] = {
 160                         MIPS32_MTC0(1,31,0),                    /* move $1 to COP0 DeSave */
 161                         MIPS32_MFC0(1,23,0),                    /* move COP0 Debug to $1 */
 162                         MIPS32_ORI(1,1,0x0100),                 /* set SSt bit in debug reg */
 163                         MIPS32_MTC0(1,23,0),                    /* move $1 to COP0 Debug */
 164                         MIPS32_B(NEG16(5)),
 165                         MIPS32_MFC0(1,31,0),                    /* move COP0 DeSave to $1 */
 166         };
 167
 168         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 169                 0, NULL, 0, NULL, 1);
 170
 171         return ERROR_OK;
 172 }
 173
 174 static int mips_ejtag_step_disable(struct mips_ejtag *ejtag_info)
 175 {
 176         static const uint32_t code[] = {
 177                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 178                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 179                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 180                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 181                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 182                         MIPS32_MFC0(1,23,0),                                                    /* move COP0 Debug to $1 */
 183                         MIPS32_LUI(2,0xFFFF),                                                   /* $2 = 0xfffffeff */
 184                         MIPS32_ORI(2,2,0xFEFF),
 185                         MIPS32_AND(1,1,2),
 186                         MIPS32_MTC0(1,23,0),                                                    /* move $1 to COP0 Debug */
 187                         MIPS32_LW(2,0,15),
 188                         MIPS32_LW(1,0,15),
 189                         MIPS32_B(NEG16(13)),
 190                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 191         };
 192
 193         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 194                 0, NULL, 0, NULL, 1);
 195
 196         return ERROR_OK;
 197 }
 198
 199 int mips_ejtag_config_step(struct mips_ejtag *ejtag_info, int enable_step)
 200 {
 201         if (enable_step)
 202                 return mips_ejtag_step_enable(ejtag_info);
 203         return mips_ejtag_step_disable(ejtag_info);
 204 }
 205
 206 int mips_ejtag_enter_debug(struct mips_ejtag *ejtag_info)
 207 {
 208         uint32_t ejtag_ctrl;
 209         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
 210
 211         /* set debug break bit */
 212         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 213         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 214
 215         /* break bit will be cleared by hardware */
 216         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 217         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 218         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 219         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0)
 220                 LOG_DEBUG("Failed to enter Debug Mode!");
 221
 222         return ERROR_OK;
 223 }
 224
 225 int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 226 {
 227         uint32_t inst;
 228         inst = MIPS32_DRET;
 229
 230         /* execute our dret instruction */
 231         mips32_pracc_exec(ejtag_info, 1, &inst, 0, NULL, 0, NULL, 0);
 232
 233         return ERROR_OK;
 234 }
 235
 236 int mips_ejtag_read_debug(struct mips_ejtag *ejtag_info, uint32_t* debug_reg)
 237 {
 238         /* read ejtag ECR */
 239         static const uint32_t code[] = {
 240                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 241                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 242                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 243                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 244                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 245                         MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $1 = MIPS32_PRACC_PARAM_OUT */
 246                         MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_OUT)),
 247                         MIPS32_MFC0(2,23,0),                                                    /* move COP0 Debug to $2 */
 248                         MIPS32_SW(2,0,1),
 249                         MIPS32_LW(2,0,15),
 250                         MIPS32_LW(1,0,15),
 251                         MIPS32_B(NEG16(12)),
 252                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 253         };
 254
 255         mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, \
 256                 0, NULL, 1, debug_reg, 1);
 257
 258         return ERROR_OK;
 259 }
 260
 261 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 262 {
 263         uint32_t ejtag_version;
 264
 265         mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 266         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 267
 268         /* get ejtag version */
 269         ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 270
 271         switch (ejtag_version)
 272         {
 273                 case 0:
 274                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 275                         break;
 276                 case 1:
 277                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 278                         break;
 279                 case 2:
 280                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 281                         break;
 282                 case 3:
 283                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 284                         break;
 285                 default:
 286                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 287                         break;
 288         }
 289         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 290                 ejtag_info->impcode & EJTAG_IMP_R3K ? " R3k" : " R4k",
 291                 ejtag_info->impcode & EJTAG_IMP_DINT ? " DINT" : "",
 292                 ejtag_info->impcode & (1 << 22) ? " ASID_8" : "",
 293                 ejtag_info->impcode & (1 << 21) ? " ASID_6" : "",
 294                 ejtag_info->impcode & EJTAG_IMP_MIPS16 ? " MIPS16" : "",
 295                 ejtag_info->impcode & EJTAG_IMP_NODMA ? " noDMA" : " DMA",
 296                 ejtag_info->impcode & EJTAG_DCR_MIPS64  ? " MIPS64" : " MIPS32");
 297
 298         if ((ejtag_info->impcode & EJTAG_IMP_NODMA) == 0)
 299                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 300
 301         /* set initial state for ejtag control reg */
 302         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 303
 304         return ERROR_OK;
 305 }
 306
 307 int mips_ejtag_fastdata_scan(struct mips_ejtag *ejtag_info, int write, uint32_t *data)
 308 {
 309         struct jtag_tap *tap;
 310         tap = ejtag_info->tap;
 311
 312         if (tap == NULL)
 313                 return ERROR_FAIL;
 314
 315         struct scan_field fields[2];
 316         uint8_t spracc = 0;
 317         uint8_t t[4] = {0, 0, 0, 0};
 318
 319         /* fastdata 1-bit register */
 320         fields[0].num_bits = 1;
 321         fields[0].out_value = &spracc;
 322         fields[0].in_value = NULL;
 323
 324         /* processor access data register 32 bit */
 325         fields[1].num_bits = 32;
 326         fields[1].out_value = t;
 327
 328         if (write)
 329         {
 330                 fields[1].in_value = NULL;
 331                 buf_set_u32(t, 0, 32, *data);
 332         }
 333         else
 334         {
 335                 fields[1].in_value = (uint8_t *) data;
 336         }
 337
 338         jtag_add_dr_scan(tap, 2, fields, TAP_IDLE);
 339         keep_alive();
 340
 341         return ERROR_OK;
 342 }