Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/* legacy_dbg_commands.c -- JTAG protocol bridge between GDB and OpenCores debug module.

   Copyright(C) 2001 Marko Mlinar, markom@opencores.org

   Code for TCP/IP copied from gdb, by Chris Ziomkowski

   Adapted for the Advanced JTAG Bridge by Nathan Yawn, (C) 2009-2010

   This file was part of the OpenRISC 1000 Architectural Simulator.

   It is now also used to connect GDB to a running hardware OpenCores / OR1200

   debug unit.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 2 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */

#include <assert.h>

#include <stdio.h>

#include <ctype.h>

#include <string.h>

#include <stdlib.h>

#include <unistd.h>

#include <stdarg.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <netinet/in.h>  // for htonl

#include "chain_commands.h"

#include "cable_common.h"

#include "errcodes.h"

#include "legacy_dbg_commands.h"

#define debug(...) //fprintf(stderr, __VA_ARGS__ )

#define LEGACY_CRC_POLY 0x04c11db7

#define DBG_CRC_SIZE 32

/* Crc of current read or written data.  */

static int legacy_crc_r, legacy_crc_w = 0;

/*----------------------------------------------------------------------------------*/

// Helper Functions

/* Generates new crc, sending in new bit input_bit */

static unsigned long legacy_crc_calc(unsigned long crc, int input_bit) {

  unsigned long d = (input_bit&1) ? 0xfffffff : 0x0000000;

  unsigned long crc_32 = ((crc >> 31)&1) ? 0xfffffff : 0x0000000;

  crc <<= 1;

  return crc ^ ((d ^ crc_32) & LEGACY_CRC_POLY);

}

/* Writes bitstream.  LS bit first if len < 0, MS bit first if len > 0.  */

static void legacy_write_stream(uint32_t stream, int len, int set_last_bit) {

  int i;

  uint32_t err;

  uint32_t outdata = 0;

  uint32_t datacpy = stream;

  // MSB needs to be transferred first, lower levels do LSB first.  Reverse.

  for(i = 0; i < len; i++) {

    outdata |= stream & 0x1;

    if(i < (len-1)) {

      outdata <<= 1;

      stream >>= 1;

    }

  }

  // Call the lower level, in case the driver has a high-speed transfer capability.

  // *** This always transfers LS bit first.

  err = jtag_write_stream(&outdata, len, set_last_bit);

  debug("legacy_write_stream, stream = 0x%X (0x%X), len = %d, set_last_bit = %d, ret = 0x%X\n", datacpy, outdata, len, set_last_bit, err);

  if(err != APP_ERR_NONE) {

    fprintf(stderr, "Error in legacy_write_stream: %s\n", get_err_string(err));

  }

  // The low level call does not compute

  // a CRC.  Do so here.  Remember, CRC is only calculated using data bits.

  if(len < 0) {

    fprintf(stderr, "Program error: legacy debug JTAG read with negative length!\n");

    /*

      len = -len;

      for(i = 0; i < len; i++) {

      legacy_crc_w = legacy_crc_calc(legacy_crc_w, stream&1);

      datacpy >>= 1;

      }

    */

  }

  else {

    for(i = len-1; i >= 0; i--) {

      legacy_crc_w = legacy_crc_calc(legacy_crc_w, (datacpy>>i)&1);

    }

  }

}

/* Gets bitstream.  LS bit first if len < 0, MS bit first if len > 0.  */

static uint32_t legacy_read_stream(unsigned long stream, int len, int set_last_bit) {

  int i;

  uint32_t data = 0, datacpy = 0;

  uint32_t outdata = stream;

  uint32_t indata;

  uint32_t err;

  // *** WARNING:  We assume that the input ("stream") will always be 0.

  // If it's ever not, then we probably need to reverse the bit order (as

  // is done in legacy_write_stream) before sending.

  // Call the lower level, in case the driver has a high-speed transfer capability.

  // This always transfers LS bit first.

  err = jtag_read_write_stream(&outdata, &indata, len, 0, set_last_bit);

  // Data comes from the legacy debug unit MSB first, so we need to 

  // reverse the bit order.

  for(i = 0; i < len; i++) {

    data |= indata & 0x1;

    if(i < (len-1)) {

      data <<= 1;

      indata >>= 1;

    }

  }

  datacpy = data;

  debug("legacy_read_stream: write 0x%X, read 0x%X, len %i, set_last_bit = %d\n", outdata, data, len, set_last_bit);

  if(err != APP_ERR_NONE) {

    fprintf(stderr, "Error in legacy_read_stream: %s\n", get_err_string(err));

  }

  // The low level call does not compute

  // a CRC.  Do so here.  Remember, CRC is only calculated using data bits.

  if(len < 0) {

    fprintf(stderr, "Program error: legacy debug JTAG read with negative length!\n");

    /*

      len = -len;

      for(i = 0; i < len; i++) {

      legacy_crc_w = legacy_crc_calc(legacy_crc_w, stream&1);

      stream >>= 1;

      legacy_crc_r = legacy_crc_calc(legacy_crc_r, datacpy&1);

      datacpy >>= 1;

      }

    */

     }

     else {

       for(i = len-1; i >= 0; i--) {

         legacy_crc_w = legacy_crc_calc(legacy_crc_w, (stream>>i)&1);

         legacy_crc_r = legacy_crc_calc(legacy_crc_r, (datacpy>>i)&1);

       }

     }

  return data;

}

//////////////////////////////////////////////////////////////////////////

// Actual operations on the legacy debug unit

/* Sets scan chain.  */

int legacy_dbg_set_chain(int chain) {

  int status, crc_generated, legacy_crc_read;

  desired_chain = chain;

try_again:

  if (current_chain == chain) return APP_ERR_NONE;

  current_chain = -1;

  debug("\nset_chain %i\n", chain);

  tap_set_shift_dr();    /* SHIFT_DR */

  /* write data, EXIT1_DR */

  legacy_crc_w = 0xffffffff;

  legacy_write_stream(((chain & 0xf) | (1<<DC_SIZE)), DC_SIZE + 1, 0);

  legacy_write_stream(legacy_crc_w, DBG_CRC_SIZE, 0);

  legacy_crc_r = 0xffffffff;

  status = legacy_read_stream(0, DC_STATUS_SIZE, 0);

  crc_generated = legacy_crc_r;

  legacy_crc_read = legacy_read_stream(0, DBG_CRC_SIZE, 1);

  debug("Status/CRC read / CRC generated: %x %x %x\n", status, legacy_crc_read, crc_generated);

  /* CRCs must match, otherwise retry */

  if (legacy_crc_read != crc_generated) {

    if (retry_do()) goto try_again;

    else return APP_ERR_CRC;

  }

  /* we should read expected status value, otherwise retry */

  if (status != 0) {

    if (retry_do()) goto try_again;

    else return APP_ERR_BAD_PARAM;

  }

  /* reset retry counter */

  retry_ok();

  tap_exit_to_idle();  // Transition the TAP back to state IDLE  

  current_chain = chain;

  debug("Successfully set chain to %i\n", current_chain);

  return APP_ERR_NONE;

}

/* sends out a command with 32bit address and 16bit length, if len >= 0 */

int legacy_dbg_command(int type, unsigned long adr, int len) {

  int status, crc_generated, legacy_crc_read;

try_again:

  legacy_dbg_set_chain(desired_chain);

  debug("\ncomm %i\n", type);

  /***** WRITEx *****/

  tap_set_shift_dr();  /* SHIFT_DR */

  /* write data, EXIT1_DR */

  legacy_crc_w = 0xffffffff;

  legacy_write_stream(((DI_WRITE_CMD & 0xf) | (0<<DC_SIZE)), DC_SIZE + 1, 0);

  legacy_write_stream(type, 4, 0);

  legacy_write_stream(adr, 32, 0);

  assert(len > 0);

  legacy_write_stream(len - 1, 16, 0);

  legacy_write_stream(legacy_crc_w, DBG_CRC_SIZE, 0);

  legacy_crc_r = 0xffffffff;

  status = legacy_read_stream(0, DC_STATUS_SIZE, 0);

  crc_generated = legacy_crc_r;

  legacy_crc_read = legacy_read_stream(0, DBG_CRC_SIZE, 1);

  /* CRCs must match, otherwise retry */

  if (legacy_crc_read != crc_generated) {

    if (retry_do()) goto try_again;

    else return APP_ERR_CRC;

  }

  /* we should read expected status value, otherwise retry */

  if (status != 0) {

    if (retry_do()) goto try_again;

    else return APP_ERR_BAD_PARAM;

  }

  tap_exit_to_idle();  // Transition the TAP back to state IDLE

  /* reset retry counter */

  retry_ok();

  return APP_ERR_NONE;

}

/* writes a ctrl reg */

int legacy_dbg_ctrl(int reset, int stall) {

  int status, crc_generated, legacy_crc_read;

try_again:

  legacy_dbg_set_chain(desired_chain);

  debug("\nctrl\n");

  /***** WRITEx *****/

  tap_set_shift_dr(); /* SHIFT_DR */

  /* write data, EXIT1_DR */

  legacy_crc_w = 0xffffffff;

  legacy_write_stream(((DI_WRITE_CTRL & 0xf) | (0<<DC_SIZE)), DC_SIZE + 1, 0);

  legacy_write_stream(reset, 1, 0);

  legacy_write_stream(stall, 1, 0);

  legacy_write_stream(0, 32, 0); // legacy_write_stream() has a max size of 32 bits, we need 50

  legacy_write_stream(0, 18, 0);

  legacy_write_stream(legacy_crc_w, DBG_CRC_SIZE, 0);

  legacy_crc_r = 0xffffffff;

  status = legacy_read_stream(0, DC_STATUS_SIZE, 0);

  crc_generated = legacy_crc_r;

  legacy_crc_read = legacy_read_stream(0, DBG_CRC_SIZE, 1);

  /* CRCs must match, otherwise retry */

  debug("did ctrl: %x %x %x\n", status, legacy_crc_read, crc_generated);

  if (legacy_crc_read != crc_generated) {

    if (retry_do()) goto try_again;

    else return APP_ERR_CRC;

  }

  /* we should read expected status value, otherwise retry */

  if (status != 0) {

    if (retry_do()) goto try_again;

    else return APP_ERR_BAD_PARAM;

  }

  tap_exit_to_idle();  // Transition the TAP back to state IDLE

  /* reset retry counter */

  retry_ok();

  return APP_ERR_NONE;

}

/* reads control register */

int legacy_dbg_ctrl_read(int *reset, int *stall) {

  int status, crc_generated, legacy_crc_read;

  try_again:

  legacy_dbg_set_chain(desired_chain);

  debug("\nctrl_read\n");

  tap_set_shift_dr(); /* SHIFT_DR */

  /* write data, EXIT1_DR */

  legacy_crc_w = 0xffffffff;

  legacy_write_stream(DI_READ_CTRL | (0<<DC_SIZE), DC_SIZE + 1, 0);

  legacy_write_stream(legacy_crc_w, DBG_CRC_SIZE, 0);

  legacy_crc_r = 0xffffffff;

  *reset = legacy_read_stream(0, 1, 0);

  *stall = legacy_read_stream(0, 1, 0);

  legacy_read_stream(0, 32, 0);  // legacy_read_stream() has a max size of 32 bits, we need 50

  legacy_read_stream(0, 18, 0);

  status = legacy_read_stream(0, DC_STATUS_SIZE, 0);

  crc_generated = legacy_crc_r;

  legacy_crc_read = legacy_read_stream(0, DBG_CRC_SIZE, 1);

  /* CRCs must match, otherwise retry */

  debug("read ctrl: %x %x %x.  reset = %i, stall = %i\n", status, legacy_crc_read, crc_generated, *reset, *stall);

  if (legacy_crc_read != crc_generated) {

    if (retry_do()) goto try_again;

    else return APP_ERR_CRC;

  }

  /* we should read expected status value, otherwise retry */

  if (status != 0) {

    if (retry_do()) goto try_again;

    else return APP_ERR_BAD_PARAM;

  }

  tap_exit_to_idle();  // Transition the TAP back to state IDLE

  /* reset retry counter */

  retry_ok();

  return APP_ERR_NONE;

}

/* issues a burst read/write */

int legacy_dbg_go(unsigned char *data, unsigned short len, int read) {

  int status, crc_generated, legacy_crc_read;

  int i;

  //try_again:

  // No point in re-trying without sending the command again first...

  legacy_dbg_set_chain(desired_chain);

  debug("\ngo len = %d\n", len);

  tap_set_shift_dr(); /* SHIFT_DR */

  /* write data, EXIT1_DR */

  legacy_crc_w = 0xffffffff;

  legacy_write_stream(DI_GO | (0<<DC_SIZE), DC_SIZE + 1, 0);

  if (!read) {

    /* reverse byte ordering, since we must send in big endian */

    for (i = 0; i < len; i++)

      legacy_write_stream(data[i], 8, 0);

  }

  legacy_write_stream(legacy_crc_w, DBG_CRC_SIZE, 0);

  legacy_crc_r = 0xffffffff;

  if (read) {

    /* reverse byte ordering, since we must send in big endian */

    for (i = 0; i < len; i++)

      data[i] = legacy_read_stream(0, 8, 0);

  }

  status = legacy_read_stream(0, DC_STATUS_SIZE, 0);

  crc_generated = legacy_crc_r;

  legacy_crc_read = legacy_read_stream(0, DBG_CRC_SIZE, 1);

  /* CRCs must match, otherwise retry */

  debug("%x %x %x\n", status, legacy_crc_read, crc_generated);

  if (legacy_crc_read != crc_generated) {

    //if (retry_do()) goto try_again;

    //else 

    return APP_ERR_CRC;

  }

  /* we should read expected status value, otherwise retry */

  if (status != 0) {

    //if (retry_do()) goto try_again;

    //else 

    return status;

  }

  tap_exit_to_idle();  // Transition the TAP back to state IDLE

  /* reset retry counter */

  retry_ok();

  return APP_ERR_NONE;

}