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 void 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         assert(tap != NULL);
  37
  38         if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != (uint32_t)new_instr)
  39         {
  40                 struct scan_field field;
  41                 uint8_t t[4];
  42
  43                 field.num_bits = tap->ir_length;
  44                 field.out_value = t;
  45                 buf_set_u32(t, 0, field.num_bits, new_instr);
  46                 field.in_value = NULL;
  47
  48                 jtag_add_ir_scan(tap, &field, TAP_IDLE);
  49         }
  50 }
  51
  52 int mips_ejtag_get_idcode(struct mips_ejtag *ejtag_info, uint32_t *idcode)
  53 {
  54         struct scan_field field;
  55
  56         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IDCODE);
  57
  58         field.num_bits = 32;
  59         field.out_value = NULL;
  60         field.in_value = (void*)idcode;
  61
  62         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  63
  64         int retval;
  65         if ((retval = jtag_execute_queue()) != ERROR_OK)
  66         {
  67                 LOG_ERROR("register read failed");
  68                 return retval;
  69         }
  70         return ERROR_OK;
  71 }
  72
  73 static int mips_ejtag_get_impcode(struct mips_ejtag *ejtag_info, uint32_t *impcode)
  74 {
  75         struct scan_field field;
  76
  77         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE);
  78
  79         field.num_bits = 32;
  80         field.out_value = NULL;
  81         field.in_value = (void*)impcode;
  82
  83         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  84
  85         int retval;
  86         if ((retval = jtag_execute_queue()) != ERROR_OK)
  87         {
  88                 LOG_ERROR("register read failed");
  89                 return retval;
  90         }
  91         return ERROR_OK;
  92 }
  93
  94 int mips_ejtag_drscan_32(struct mips_ejtag *ejtag_info, uint32_t *data)
  95 {
  96         struct jtag_tap *tap;
  97         tap  = ejtag_info->tap;
  98         assert(tap != NULL);
  99
 100         struct scan_field field;
 101         uint8_t t[4], r[4];
 102         int retval;
 103
 104         field.num_bits = 32;
 105         field.out_value = t;
 106         buf_set_u32(t, 0, field.num_bits, *data);
 107         field.in_value = r;
 108
 109         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 110
 111         if ((retval = jtag_execute_queue()) != ERROR_OK)
 112         {
 113                 LOG_ERROR("register read failed");
 114                 return retval;
 115         }
 116
 117         *data = buf_get_u32(field.in_value, 0, 32);
 118
 119         keep_alive();
 120
 121         return ERROR_OK;
 122 }
 123
 124 int mips_ejtag_drscan_8(struct mips_ejtag *ejtag_info, uint32_t *data)
 125 {
 126         struct jtag_tap *tap;
 127         tap  = ejtag_info->tap;
 128         assert(tap != NULL);
 129
 130         struct scan_field field;
 131         uint8_t t[4] = {0, 0, 0, 0}, r[4];
 132         int retval;
 133
 134         field.num_bits = 8;
 135         field.out_value = t;
 136         buf_set_u32(t, 0, field.num_bits, *data);
 137         field.in_value = r;
 138
 139         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 140
 141         if ((retval = jtag_execute_queue()) != ERROR_OK)
 142         {
 143                 LOG_ERROR("register read failed");
 144                 return retval;
 145         }
 146
 147         *data = buf_get_u32(field.in_value, 0, 32);
 148
 149         keep_alive();
 150
 151         return ERROR_OK;
 152 }
 153
 154 static int mips_ejtag_step_enable(struct mips_ejtag *ejtag_info)
 155 {
 156         static const uint32_t code[] = {
 157                         MIPS32_MTC0(1,31,0),                    /* move $1 to COP0 DeSave */
 158                         MIPS32_MFC0(1,23,0),                    /* move COP0 Debug to $1 */
 159                         MIPS32_ORI(1,1,0x0100),                 /* set SSt bit in debug reg */
 160                         MIPS32_MTC0(1,23,0),                    /* move $1 to COP0 Debug */
 161                         MIPS32_B(NEG16(5)),
 162                         MIPS32_MFC0(1,31,0),                    /* move COP0 DeSave to $1 */
 163         };
 164
 165         return mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
 166                         0, NULL, 0, NULL, 1);
 167 }
 168
 169 static int mips_ejtag_step_disable(struct mips_ejtag *ejtag_info)
 170 {
 171         static const uint32_t code[] = {
 172                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 173                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 174                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 175                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 176                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 177                         MIPS32_MFC0(1,23,0),                                                    /* move COP0 Debug to $1 */
 178                         MIPS32_LUI(2,0xFFFF),                                                   /* $2 = 0xfffffeff */
 179                         MIPS32_ORI(2,2,0xFEFF),
 180                         MIPS32_AND(1,1,2),
 181                         MIPS32_MTC0(1,23,0),                                                    /* move $1 to COP0 Debug */
 182                         MIPS32_LW(2,0,15),
 183                         MIPS32_LW(1,0,15),
 184                         MIPS32_B(NEG16(13)),
 185                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 186         };
 187
 188         return mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
 189                 0, NULL, 0, NULL, 1);
 190 }
 191
 192 int mips_ejtag_config_step(struct mips_ejtag *ejtag_info, int enable_step)
 193 {
 194         if (enable_step)
 195                 return mips_ejtag_step_enable(ejtag_info);
 196         return mips_ejtag_step_disable(ejtag_info);
 197 }
 198
 199 int mips_ejtag_enter_debug(struct mips_ejtag *ejtag_info)
 200 {
 201         uint32_t ejtag_ctrl;
 202         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
 203
 204         /* set debug break bit */
 205         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 206         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 207
 208         /* break bit will be cleared by hardware */
 209         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 210         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 211         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 212         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0)
 213         {
 214                 LOG_ERROR("Failed to enter Debug Mode!");
 215                 return ERROR_FAIL;
 216         }
 217
 218         return ERROR_OK;
 219 }
 220
 221 int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 222 {
 223         uint32_t inst;
 224         inst = MIPS32_DRET;
 225
 226         /* execute our dret instruction */
 227         return mips32_pracc_exec(ejtag_info, 1, &inst, 0, NULL, 0, NULL, 0);
 228 }
 229
 230 int mips_ejtag_read_debug(struct mips_ejtag *ejtag_info, uint32_t* debug_reg)
 231 {
 232         /* read ejtag ECR */
 233         static const uint32_t code[] = {
 234                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 235                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
 236                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 237                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 238                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 239                         MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $1 = MIPS32_PRACC_PARAM_OUT */
 240                         MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_OUT)),
 241                         MIPS32_MFC0(2,23,0),                                                    /* move COP0 Debug to $2 */
 242                         MIPS32_SW(2,0,1),
 243                         MIPS32_LW(2,0,15),
 244                         MIPS32_LW(1,0,15),
 245                         MIPS32_B(NEG16(12)),
 246                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 247         };
 248
 249         return mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code,
 250                 0, NULL, 1, debug_reg, 1);
 251 }
 252
 253 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 254 {
 255         uint32_t ejtag_version;
 256         int retval;
 257
 258         retval = mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 259         if (retval != ERROR_OK)
 260                 return retval;
 261         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 262
 263         /* get ejtag version */
 264         ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 265
 266         switch (ejtag_version)
 267         {
 268                 case 0:
 269                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 270                         break;
 271                 case 1:
 272                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 273                         break;
 274                 case 2:
 275                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 276                         break;
 277                 case 3:
 278                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 279                         break;
 280                 default:
 281                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 282                         break;
 283         }
 284         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 285                 ejtag_info->impcode & EJTAG_IMP_R3K ? " R3k" : " R4k",
 286                 ejtag_info->impcode & EJTAG_IMP_DINT ? " DINT" : "",
 287                 ejtag_info->impcode & (1 << 22) ? " ASID_8" : "",
 288                 ejtag_info->impcode & (1 << 21) ? " ASID_6" : "",
 289                 ejtag_info->impcode & EJTAG_IMP_MIPS16 ? " MIPS16" : "",
 290                 ejtag_info->impcode & EJTAG_IMP_NODMA ? " noDMA" : " DMA",
 291                 ejtag_info->impcode & EJTAG_DCR_MIPS64  ? " MIPS64" : " MIPS32");
 292
 293         if ((ejtag_info->impcode & EJTAG_IMP_NODMA) == 0)
 294                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 295
 296         /* set initial state for ejtag control reg */
 297         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 298         ejtag_info->fast_access_save = -1;
 299
 300         return ERROR_OK;
 301 }
 302
 303 int mips_ejtag_fastdata_scan(struct mips_ejtag *ejtag_info, int write_t, uint32_t *data)
 304 {
 305         struct jtag_tap *tap;
 306         tap = ejtag_info->tap;
 307         assert(tap != NULL);
 308
 309         struct scan_field fields[2];
 310         uint8_t spracc = 0;
 311         uint8_t t[4] = {0, 0, 0, 0};
 312
 313         /* fastdata 1-bit register */
 314         fields[0].num_bits = 1;
 315         fields[0].out_value = &spracc;
 316         fields[0].in_value = NULL;
 317
 318         /* processor access data register 32 bit */
 319         fields[1].num_bits = 32;
 320         fields[1].out_value = t;
 321
 322         if (write_t)
 323         {
 324                 fields[1].in_value = NULL;
 325                 buf_set_u32(t, 0, 32, *data);
 326         }
 327         else
 328         {
 329                 fields[1].in_value = (uint8_t *) data;
 330         }
 331
 332         jtag_add_dr_scan(tap, 2, fields, TAP_IDLE);
 333         keep_alive();
 334
 335         return ERROR_OK;
 336 }