stk500v2.c

这是一个非常有价值的参考代码

/*
 * avrdude - A Downloader/Uploader for AVR device programmers
 * Copyright (C) 2005 Erik Walthinsen
 * Copyright (C) 2002-2004 Brian S. Dean <[e-mail]>
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/* $Id: stk500v2.c,v 1.8 2005/09/16 21:23:14 bdean Exp $ */
/* Based on Id: stk500.c,v 1.46 2004/12/22 01:52:45 bdean Exp */

/*
 * avrdude interface for Atmel STK500V2 programmer
 *
 * Note: most commands use the "universal command" feature of the
 * programmer in a "pass through" mode, exceptions are "program
 * enable", "paged read", and "paged write".
 *
 */

#include "ac_cfg.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/time.h>
#include <time.h>

#include "avr.h"
#include "pgm.h"
#include "stk500_private.h"	// temp until all code converted
#include "stk500v2_private.h"
#include "serial.h"

#define STK500V2_XTAL 7372800U

#if 0
#define DEBUG(format,args...) fprintf(stderr, format, ## args)
#else
#define DEBUG(format,args...)
#endif

#if 0
#define DEBUGRECV(format,args...) fprintf(stderr, format, ## args)
#else
#define DEBUGRECV(format,args...)
#endif


extern int    verbose;
extern char * progname;
extern int do_cycles;

static unsigned char command_sequence = 1;


static int stk500v2_getparm(PROGRAMMER * pgm, unsigned char parm, unsigned char * value);
static int stk500v2_setparm(PROGRAMMER * pgm, unsigned char parm, unsigned char value);
static void stk500v2_print_parms1(PROGRAMMER * pgm, char * p);
static int stk500v2_is_page_empty(unsigned int address, int page_size,
                                  const unsigned char *buf);


static int stk500v2_send(PROGRAMMER * pgm, unsigned char * data, size_t len)
{
  unsigned char buf[275 + 6];		// max MESSAGE_BODY of 275 bytes, 6 bytes overhead
  int i;

  buf[0] = MESSAGE_START;
  buf[1] = command_sequence;
  buf[2] = len / 256;
  buf[3] = len % 256;
  buf[4] = TOKEN;
  memcpy(buf+5, data, len);

  // calculate the XOR checksum
  buf[5+len] = 0;
  for (i=0;i<5+len;i++)
    buf[5+len] ^= buf[i];

  DEBUG("STK500V2: stk500v2_send(");
  for (i=0;i<len+6;i++) DEBUG("0x%02x ",buf[i]);
  DEBUG(", %d)\n",len+6);

  if (serial_send(pgm->fd, buf, len+6) != 0) {
    fprintf(stderr,"%s: stk500_send(): failed to send command to serial port\n",progname);
    exit(1);
  }

  return 0;
}


static int stk500v2_drain(PROGRAMMER * pgm, int display)
{
  return serial_drain(pgm->fd, display);
}


static int stk500v2_recv(PROGRAMMER * pgm, unsigned char msg[], size_t maxsize) {
  enum states { sINIT, sSTART, sSEQNUM, sSIZE1, sSIZE2, sTOKEN, sDATA, sCSUM, sDONE }  state = sSTART;
  int msglen = 0;
  int curlen = 0;
  int timeout = 0;
  unsigned char c, checksum = 0;

  long timeoutval = 5;		// seconds
  struct timeval tv;
  double tstart, tnow;

  DEBUG("STK500V2: stk500v2_recv(): ");

  gettimeofday(&tv, NULL);
  tstart = tv.tv_sec;

  while ( (state != sDONE ) && (!timeout) ) {
    if (serial_recv(pgm->fd, &c, 1) < 0)
      goto timedout;
    DEBUG("0x%02x ",c);
    checksum ^= c;

    switch (state) {
      case sSTART:
        DEBUGRECV("hoping for start token...");
        if (c == MESSAGE_START) {
          DEBUGRECV("got it\n");
          checksum = MESSAGE_START;
          state = sSEQNUM;
        } else
          DEBUGRECV("sorry\n");
        break;
      case sSEQNUM:
        DEBUGRECV("hoping for sequence...\n");
        if (c == command_sequence) {
          DEBUGRECV("got it, incrementing\n");
          state = sSIZE1;
          command_sequence++;
        } else {
          DEBUGRECV("sorry\n");
          state = sSTART;
        }
        break;
      case sSIZE1:
        DEBUGRECV("hoping for size LSB\n");
        msglen = c*256;
        state = sSIZE2;
        break;
      case sSIZE2:
        DEBUGRECV("hoping for size MSB...");
        msglen += c;
        DEBUG(" msg is %d bytes\n",msglen);
        state = sTOKEN;
        break;
      case sTOKEN:
        if (c == TOKEN) state = sDATA;
        else state = sSTART;
        break;
      case sDATA:
        if (curlen < maxsize) {
          msg[curlen] = c;
        } else {
          fprintf(stderr, "%s: stk500v2_recv(): buffer too small, received %d byte into %zd byte buffer\n",
                  progname,curlen,maxsize);
          return -2;
        }
        if ((curlen == 0) && (msg[0] == ANSWER_CKSUM_ERROR)) {
          fprintf(stderr, "%s: stk500v2_recv(): previous packet sent with wrong checksum\n",
                  progname);
          return -3;
        }
        curlen++;
        if (curlen == msglen) state = sCSUM;
        break;
      case sCSUM:
        if (checksum == 0) {
          state = sDONE;
        } else {
          state = sSTART;
          fprintf(stderr, "%s: stk500v2_recv(): checksum error\n",
                  progname);
          return -4;
        }
        break;
      default:
        fprintf(stderr, "%s: stk500v2_recv(): unknown state\n",
                progname);
        return -5;
     } /* switch */

     gettimeofday(&tv, NULL);
     tnow = tv.tv_sec;
     if (tnow-tstart > timeoutval) {			// wuff - signed/unsigned/overflow
      timedout:
       fprintf(stderr, "%s: stk500_2_ReceiveMessage(): timeout\n",
               progname);
       return -1;
     }

  } /* while */
  DEBUG("\n");

  return msglen+6;
}



static int stk500v2_getsync(PROGRAMMER * pgm) {
  int tries = 0;
  unsigned char buf[1], resp[32];
  int status;

  DEBUG("STK500V2: stk500v2_getsync()\n");

retry:
  tries++;

  // send the sync command and see if we can get there
  buf[0] = CMD_SIGN_ON;
  stk500v2_send(pgm, buf, 1);

  // try to get the response back and see where we got
  status = stk500v2_recv(pgm, resp, sizeof(resp));

  // if we got bytes returned, check to see what came back
  if (status > 0) {
    if ((resp[0] == CMD_SIGN_ON) && (resp[1] == STATUS_CMD_OK)) {
      // success!
      return 0;
    } else {
      if (tries > 33) {
        fprintf(stderr,
                "%s: stk500v2_getsync(): can't communicate with device: resp=0x%02x\n",
                progname, resp[0]);
        return -6;
      } else
        goto retry;
    }

  // or if we got a timeout
  } else if (status == -1) {
    if (tries > 33) {
      fprintf(stderr,"%s: stk500v2_getsync(): timeout communicating with programmer\n",
              progname);
      return -1;
    } else
      goto retry;

  // or any other error
  } else {
    if (tries > 33) {
      fprintf(stderr,"%s: stk500v2_getsync(): error communicating with programmer: (%d)\n",
              progname,status);
    } else
      goto retry;
  }

  return 0;
}

static int stk500v2_command(PROGRAMMER * pgm, unsigned char * buf, size_t len, size_t maxlen) {
  int i;
  int tries = 0;
  int status;

  DEBUG("STK500V2: stk500v2_command(");
  for (i=0;i<len;i++) DEBUG("0x%02hhx ",buf[i]);
  DEBUG(", %d)\n",len);

retry:
  tries++;

  // send the command to the programmer
  stk500v2_send(pgm,buf,len);

  // attempt to read the status back
  status = stk500v2_recv(pgm,buf,maxlen);

  // if we got a successful readback, return
  if (status > 0) {
    DEBUG(" = %d\n",status);
    return status;
  }

  // otherwise try to sync up again
  status = stk500v2_getsync(pgm);
  if (status != 0) {
    if (tries > 33) {
      fprintf(stderr,"%s: stk500v2_command(): failed miserably to execute command 0x%02x\n",
              progname,buf[0]);
      return -1;
    } else
      goto retry;
  }

  DEBUG(" = 0\n");
  return 0;
}

static int stk500v2_cmd(PROGRAMMER * pgm, unsigned char cmd[4],
                        unsigned char res[4])
{
  unsigned char buf[8];
  int result;

  DEBUG("STK500V2: stk500v2_cmd(%02x,%02x,%02x,%02x)\n",cmd[0],cmd[1],cmd[2],cmd[3]);

  buf[0] = CMD_SPI_MULTI;
  buf[1] = 4;
  buf[2] = 4;
  buf[3] = 0;
  buf[4] = cmd[0];
  buf[5] = cmd[1];
  buf[6] = cmd[2];
  buf[7] = cmd[3];

  result = stk500v2_command(pgm, buf, 8, sizeof(buf));
  if (buf[1] != STATUS_CMD_OK) {
    fprintf(stderr, "%s: stk500v2_cmd(): failed to send command\n",
            progname);
    return -1;
  }

  res[0] = buf[2];
  res[1] = buf[3];
  res[2] = buf[4];
  res[3] = buf[5];

  return 0;
}


/*
 * issue the 'chip erase' command to the AVR device
 */
static int stk500v2_chip_erase(PROGRAMMER * pgm, AVRPART * p)
{
  int result;
  unsigned char buf[16];

  if (p->op[AVR_OP_CHIP_ERASE] == NULL) {
    fprintf(stderr, "%s: stk500v2_chip_erase: chip erase instruction not defined for part \"%s\"\n",
            progname, p->desc);
    return -1;
  }

  pgm->pgm_led(pgm, ON);

  buf[0] = CMD_CHIP_ERASE_ISP;
  buf[1] = p->chip_erase_delay / 1000;
  buf[2] = 0;	// use delay (?)
  avr_set_bits(p->op[AVR_OP_CHIP_ERASE], buf+3);
  result = stk500v2_command(pgm, buf, 7, sizeof(buf));
  usleep(p->chip_erase_delay);
  pgm->initialize(pgm, p);

  pgm->pgm_led(pgm, OFF);

  return result;
}

/*
 * issue the 'program enable' command to the AVR device
 */
static int stk500v2_program_enable(PROGRAMMER * pgm, AVRPART * p)
{
  unsigned char buf[16];

  if (p->op[AVR_OP_PGM_ENABLE] == NULL) {
    fprintf(stderr, "%s: stk500v2_program_enable(): program enable instruction not defined for part \"%s\"\n",
            progname, p->desc);
    return -1;
  }

  buf[0] = CMD_ENTER_PROGMODE_ISP;
  buf[1] = p->timeout;
  buf[2] = p->stabdelay;
  buf[3] = p->cmdexedelay;
  buf[4] = p->synchloops;
  buf[5] = p->bytedelay;
  buf[6] = p->pollvalue;
  buf[7] = p->pollindex;
  avr_set_bits(p->op[AVR_OP_PGM_ENABLE], buf+8);

  return stk500v2_command(pgm, buf, 12, sizeof(buf));
}



/*
 * initialize the AVR device and prepare it to accept commands
 */
static int stk500v2_initialize(PROGRAMMER * pgm, AVRPART * p)
{
  return pgm->program_enable(pgm, p);
}


static void stk500v2_disable(PROGRAMMER * pgm)
{
  unsigned char buf[16];
  int result;

  buf[0] = CMD_LEAVE_PROGMODE_ISP;
  buf[1] = 1; // preDelay;
  buf[2] = 1; // postDelay;

  result = stk500v2_command(pgm, buf, 3, sizeof(buf));

  if (buf[1] != STATUS_CMD_OK) {
    fprintf(stderr, "%s: stk500v2_disable(): failed to leave programming mode, got 0x%02x\n",
            progname,buf[1]);
    exit(1);
  }

  return;
}

static void stk500v2_enable(PROGRAMMER * pgm)
{
  return;
}


static int stk500v2_open(PROGRAMMER * pgm, char * port)
{
  DEBUG("STK500V2: stk500v2_open()\n");

  strcpy(pgm->port, port);
  if (pgm->baudrate)
    pgm->fd = serial_open(port, pgm->baudrate);
  else
    pgm->fd = serial_open(port, 115200);

  /*
   * drain any extraneous input
   */
  stk500v2_drain(pgm, 0);

  stk500v2_getsync(pgm);

  stk500v2_drain(pgm, 0);

  return 0;
}


static void stk500v2_close(PROGRAMMER * pgm)
{
  DEBUG("STK500V2: stk500v2_close()\n");

  serial_close(pgm->fd);
  pgm->fd = -1;
}


static int stk500v2_loadaddr(PROGRAMMER * pgm, unsigned int addr)
{
  unsigned char buf[16];
  int result;

  DEBUG("STK500V2: stk500v2_loadaddr(%d)\n",addr);

  buf[0] = CMD_LOAD_ADDRESS;
  buf[1] = (addr >> 24) & 0xff;
  buf[2] = (addr >> 16) & 0xff;
  buf[3] = (addr >> 8) & 0xff;
  buf[4] = addr & 0xff;

  result = stk500v2_command(pgm, buf, 5, sizeof(buf));

  if (buf[1] != STATUS_CMD_OK) {
    fprintf(stderr, "%s: stk500v2_loadaddr(): failed to set load address, got 0x%02x\n",
            progname,buf[1]);
    return -1;
  }

  return 0;
}