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