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  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  21  ***************************************************************************/
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include "mips32.h"
  27 #include "mips_ejtag.h"
  28
  29
  30 int mips_ejtag_set_instr(mips_ejtag_t *ejtag_info, int new_instr, void *delete_me_and_submit_patch)
  31 {
  32         jtag_tap_t *tap;
  33
  34         tap = ejtag_info->tap;
  35         if (tap==NULL)
  36                 return ERROR_FAIL;
  37
  38         if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != (uint32_t)new_instr)
  39         {
  40                 scan_field_t field;
  41                 uint8_t t[4];
  42
  43                 field.tap = tap;
  44                 field.num_bits = tap->ir_length;
  45                 field.out_value = t;
  46                 buf_set_u32(field.out_value, 0, field.num_bits, new_instr);
  47
  48                 field.in_value = NULL;
  49
  50
  51
  52
  53                 jtag_add_ir_scan(1, &field, jtag_get_end_state());
  54         }
  55
  56         return ERROR_OK;
  57 }
  58
  59 int mips_ejtag_get_idcode(mips_ejtag_t *ejtag_info, uint32_t *idcode)
  60 {
  61         scan_field_t field;
  62
  63         jtag_set_end_state(TAP_IDLE);
  64
  65         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IDCODE, NULL);
  66
  67         field.tap = ejtag_info->tap;
  68         field.num_bits = 32;
  69         field.out_value = NULL;
  70
  71         field.in_value = (void*)idcode;
  72
  73
  74
  75
  76         jtag_add_dr_scan(1, &field, jtag_get_end_state());
  77
  78         if (jtag_execute_queue() != ERROR_OK)
  79         {
  80                 LOG_ERROR("register read failed");
  81         }
  82
  83         return ERROR_OK;
  84 }
  85
  86 int mips_ejtag_get_impcode(mips_ejtag_t *ejtag_info, uint32_t *impcode)
  87 {
  88         scan_field_t field;
  89
  90         jtag_set_end_state(TAP_IDLE);
  91
  92         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE, NULL);
  93
  94         field.tap = ejtag_info->tap;
  95         field.num_bits = 32;
  96         field.out_value = NULL;
  97
  98         field.in_value = (void*)impcode;
  99
 100
 101
 102
 103         jtag_add_dr_scan(1, &field, jtag_get_end_state());
 104
 105         if (jtag_execute_queue() != ERROR_OK)
 106         {
 107                 LOG_ERROR("register read failed");
 108         }
 109
 110         return ERROR_OK;
 111 }
 112
 113 int mips_ejtag_drscan_32(mips_ejtag_t *ejtag_info, uint32_t *data)
 114 {
 115         jtag_tap_t *tap;
 116         tap  = ejtag_info->tap;
 117
 118         if (tap==NULL)
 119                 return ERROR_FAIL;
 120         scan_field_t field;
 121         uint8_t t[4], r[4];
 122         int retval;
 123
 124         field.tap = tap;
 125         field.num_bits = 32;
 126         field.out_value = t;
 127         buf_set_u32(field.out_value, 0, field.num_bits, *data);
 128
 129         field.in_value = r;
 130
 131
 132
 133
 134         jtag_add_dr_scan(1, &field, jtag_get_end_state());
 135
 136         if ((retval = jtag_execute_queue()) != ERROR_OK)
 137         {
 138                 LOG_ERROR("register read failed");
 139                 return retval;
 140         }
 141
 142         *data = buf_get_u32(field.in_value, 0, 32);
 143
 144         keep_alive();
 145
 146         return ERROR_OK;
 147 }
 148
 149 int mips_ejtag_step_enable(mips_ejtag_t *ejtag_info)
 150 {
 151         uint32_t code[] = {
 152                         MIPS32_MTC0(1,31,0),                    /* move $1 to COP0 DeSave */
 153                         MIPS32_MFC0(1,23,0),                    /* move COP0 Debug to $1 */
 154                         MIPS32_ORI(1,1,0x0100),                 /* set SSt bit in debug reg */
 155                         MIPS32_MTC0(1,23,0),                    /* move $1 to COP0 Debug */
 156                         MIPS32_MFC0(1,31,0),                    /* move COP0 DeSave to $1 */
 157                         MIPS32_NOP,
 158                         MIPS32_B(NEG16(7)),
 159                         MIPS32_NOP,
 160         };
 161
 162         mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
 163                 0, NULL, 0, NULL, 1);
 164
 165         return ERROR_OK;
 166 }
 167 int mips_ejtag_step_disable(mips_ejtag_t *ejtag_info)
 168 {
 169         uint32_t code[] = {
 170                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 171                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),     /* $15 = MIPS32_PRACC_STACK */
 172                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 173                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 174                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 175                         MIPS32_MFC0(1,23,0),                                                    /* move COP0 Debug to $1 */
 176                         MIPS32_LUI(2,0xFFFF),                                                   /* $2 = 0xfffffeff */
 177                         MIPS32_ORI(2,2,0xFEFF),
 178                         MIPS32_AND(1,1,2),
 179                         MIPS32_MTC0(1,23,0),                                                    /* move $1 to COP0 Debug */
 180                         MIPS32_LW(2,0,15),
 181                         MIPS32_LW(1,0,15),
 182                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 183                         MIPS32_NOP,
 184                         MIPS32_B(NEG16(15)),
 185                         MIPS32_NOP,
 186         };
 187
 188         mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
 189                 0, NULL, 0, NULL, 1);
 190
 191         return ERROR_OK;
 192 }
 193
 194 int mips_ejtag_config_step(mips_ejtag_t *ejtag_info, int enable_step)
 195 {
 196         if (enable_step)
 197                 return mips_ejtag_step_enable(ejtag_info);
 198         return mips_ejtag_step_disable(ejtag_info);
 199 }
 200
 201 int mips_ejtag_enter_debug(mips_ejtag_t *ejtag_info)
 202 {
 203         uint32_t ejtag_ctrl;
 204         jtag_set_end_state(TAP_IDLE);
 205         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
 206
 207         /* set debug break bit */
 208         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 209         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 210
 211         /* break bit will be cleared by hardware */
 212         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 213         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 214         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 215         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0)
 216                 LOG_DEBUG("Failed to enter Debug Mode!");
 217
 218         return ERROR_OK;
 219 }
 220
 221 int mips_ejtag_exit_debug(mips_ejtag_t *ejtag_info)
 222 {
 223         uint32_t inst;
 224         inst = MIPS32_DRET;
 225
 226         /* execute our dret instruction */
 227         mips32_pracc_exec(ejtag_info, 1, &inst, 0, NULL, 0, NULL, 0);
 228
 229         return ERROR_OK;
 230 }
 231
 232 int mips_ejtag_read_debug(mips_ejtag_t *ejtag_info, uint32_t* debug_reg)
 233 {
 234         /* read ejtag ECR */
 235         uint32_t code[] = {
 236                         MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
 237                         MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),     /* $15 = MIPS32_PRACC_STACK */
 238                         MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
 239                         MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
 240                         MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
 241                         MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $1 = MIPS32_PRACC_PARAM_OUT */
 242                         MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_OUT)),
 243                         MIPS32_MFC0(2,23,0),                                                    /* move COP0 Debug to $2 */
 244                         MIPS32_SW(2,0,1),
 245                         MIPS32_LW(2,0,15),
 246                         MIPS32_LW(1,0,15),
 247                         MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
 248                         MIPS32_NOP,
 249                         MIPS32_B(NEG16(14)),
 250                         MIPS32_NOP,
 251         };
 252
 253         mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
 254                 0, NULL, 1, debug_reg, 1);
 255
 256         return ERROR_OK;
 257 }
 258
 259 int mips_ejtag_init(mips_ejtag_t *ejtag_info)
 260 {
 261         uint32_t ejtag_version;
 262
 263         mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 264         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 265
 266         /* get ejtag version */
 267         ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 268
 269         switch (ejtag_version)
 270         {
 271                 case 0:
 272                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 273                         break;
 274                 case 1:
 275                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 276                         break;
 277                 case 2:
 278                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 279                         break;
 280                 case 3:
 281                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 282                         break;
 283                 default:
 284                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 285                         break;
 286         }
 287         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 288                 ejtag_info->impcode & (1<<28) ? " R3k":    " R4k",
 289                 ejtag_info->impcode & (1<<24) ? " DINT":   "",
 290                 ejtag_info->impcode & (1<<22) ? " ASID_8": "",
 291                 ejtag_info->impcode & (1<<21) ? " ASID_6": "",
 292                 ejtag_info->impcode & (1<<16) ? " MIPS16": "",
 293                 ejtag_info->impcode & (1<<14) ? " noDMA":  " DMA",
 294                 ejtag_info->impcode & (1<<0)  ? " MIPS64": " MIPS32"
 295         );
 296
 297         if ((ejtag_info->impcode & (1<<14)) == 0)
 298                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 299
 300         /* set initial state for ejtag control reg */
 301         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 302
 303         return ERROR_OK;
 304 }