mspdebug/bsl.c

337 lines
6.8 KiB
C

/* MSPDebug - debugging tool for the eZ430
* Copyright (C) 2009, 2010 Daniel Beer
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include "device.h"
#include "util.h"
static int serial_fd;
#define DATA_HDR 0x80
#define DATA_ACK 0x90
#define DATA_NAK 0xA0
static int bsl_ack(void)
{
u_int8_t reply;
if (read_with_timeout(serial_fd, &reply, 1) < 0) {
fprintf(stderr, "bsl: failed to receive reply\n");
return -1;
}
if (reply == DATA_NAK) {
fprintf(stderr, "bsl: received NAK\n");
return -1;
}
if (reply != DATA_ACK) {
fprintf(stderr, "bsl: bad ack character: %x\n", reply);
return -1;
}
return 0;
}
static int bsl_sync(void)
{
static const u_int8_t c = DATA_HDR;
int tries = 2;
if (tcflush(serial_fd, TCIFLUSH) < 0) {
perror("bsl: tcflush");
return -1;
}
while (tries--)
if (!(write_all(serial_fd, &c, 1) || bsl_ack()))
return 0;
fprintf(stderr, "bsl: sync failed\n");
return -1;
}
static int send_command(int code, u_int16_t addr,
const u_int8_t *data, int len)
{
u_int8_t pktbuf[256];
u_int8_t cklow = 0xff;
u_int8_t ckhigh = 0xff;
int pktlen = data ? len + 4 : 4;
int i;
if (pktlen + 6 > sizeof(pktbuf)) {
fprintf(stderr, "bsl: payload too large: %d\n", len);
return -1;
}
pktbuf[0] = DATA_HDR;
pktbuf[1] = code;
pktbuf[2] = pktlen;
pktbuf[3] = pktlen;
pktbuf[4] = addr & 0xff;
pktbuf[5] = addr >> 8;
pktbuf[6] = len & 0xff;
pktbuf[7] = len >> 8;
if (data)
memcpy(pktbuf + 8, data, len);
for (i = 0; i < pktlen + 4; i += 2)
cklow ^= pktbuf[i];
for (i = 1; i < pktlen + 4; i += 2)
ckhigh ^= pktbuf[i];
pktbuf[pktlen + 4] = cklow;
pktbuf[pktlen + 5] = ckhigh;
return write_all(serial_fd, pktbuf, pktlen + 6);
}
static u_int8_t reply_buf[256];
static int reply_len;
static int verify_checksum(void)
{
u_int8_t cklow = 0xff;
u_int8_t ckhigh = 0xff;
int i;
for (i = 0; i < reply_len; i += 2)
cklow ^= reply_buf[i];
for (i = 1; i < reply_len; i += 2)
ckhigh ^= reply_buf[i];
if (cklow || ckhigh) {
fprintf(stderr, "bsl: checksum invalid (%02x %02x)\n",
cklow, ckhigh);
return -1;
}
return 0;
}
static int fetch_reply(void)
{
reply_len = 0;
for (;;) {
int r = read_with_timeout(serial_fd, reply_buf + reply_len,
sizeof(reply_buf) - reply_len);
if (r < 0)
return -1;
reply_len += r;
if (reply_buf[0] == DATA_ACK) {
return 0;
} else if (reply_buf[0] == DATA_HDR) {
if (reply_len >= 6 &&
reply_len == reply_buf[2] + 6)
return verify_checksum();
} else if (reply_buf[0] == DATA_NAK) {
fprintf(stderr, "bsl: received NAK\n");
return -1;
} else {
fprintf(stderr, "bsl: unknown reply type: %02x\n",
reply_buf[0]);
return -1;
}
if (reply_len >= sizeof(reply_buf)) {
fprintf(stderr, "bsl: reply buffer overflow\n");
return -1;
}
}
}
static int bsl_xfer(int command_code, u_int16_t addr, const u_int8_t *txdata,
int len)
{
if (bsl_sync() < 0 ||
send_command(command_code, addr, txdata, len) < 0 ||
fetch_reply() < 0) {
fprintf(stderr, "bsl: failed on command 0x%02x "
"(addr = 0x%04x, len = 0x%04x)\n",
command_code, addr, len);
return -1;
}
return 0;
}
#define CMD_TX_DATA 0x38
#define CMD_ERASE 0x39
#define CMD_RX_DATA 0x3a
#define CMD_RESET 0x3b
static void bsl_close(void)
{
bsl_xfer(CMD_RESET, 0, NULL, 0);
close(serial_fd);
}
static int bsl_control(device_ctl_t type)
{
fprintf(stderr, "bsl: CPU control is not implemented\n");
return -1;
}
static int bsl_wait(void)
{
return 0;
}
static int bsl_breakpoint(u_int16_t addr)
{
fprintf(stderr, "bsl: breakpoints are not implemented\n");
return -1;
}
static int bsl_getregs(u_int16_t *regs)
{
fprintf(stderr, "bsl: register fetch is not implemented\n");
return -1;
}
static int bsl_setregs(const u_int16_t *regs)
{
fprintf(stderr, "bsl: register store is not implemented\n");
return -1;
}
static int bsl_writemem(u_int16_t addr, const u_int8_t *mem, int len)
{
fprintf(stderr, "bsl: memory write is not implemented\n");
return -1;
}
static int bsl_readmem(u_int16_t addr, u_int8_t *mem, int len)
{
while (len) {
int count = len;
if (count > 128)
count = 128;
if (bsl_xfer(CMD_TX_DATA, addr, NULL, count) < 0) {
fprintf(stderr, "bsl: failed to read memory\n");
return -1;
}
if (count > reply_buf[2])
count = reply_buf[2];
memcpy(mem, reply_buf + 4, count);
mem += count;
len -= count;
}
return 0;
}
const static struct device bsl_device = {
.close = bsl_close,
.control = bsl_control,
.wait = bsl_wait,
.breakpoint = bsl_breakpoint,
.getregs = bsl_getregs,
.setregs = bsl_setregs,
.writemem = bsl_writemem,
.readmem = bsl_readmem
};
#include <sys/ioctl.h>
static int enter_via_fet(void)
{
u_int8_t buf[16];
u_int8_t *data = buf;
int len = 8;
/* Enter bootloader command */
if (write_all(serial_fd, (u_int8_t *)"\x7e\x24\x01\x9d\x5a\x7e", 6)) {
fprintf(stderr, "bsl: couldn't write bootloader transition "
"command\n");
return -1;
}
/* Wait for reply */
while (len) {
int r = read_with_timeout(serial_fd, data, len);
if (r < 0) {
fprintf(stderr, "bsl: couldn't read bootloader "
"transition acknowledgement\n");
return -1;
}
data += r;
len -= r;
}
/* Check that it's what we expect */
if (memcmp(buf, "\x06\x00\x24\x00\x00\x00\x61\x01", 8)) {
fprintf(stderr, "bsl: bootloader start returned error %d\n",
buf[5]);
return -1;
}
return 0;
}
const struct device *bsl_open(const char *device)
{
serial_fd = open_serial(device, B460800);
if (serial_fd < 0) {
fprintf(stderr, "bsl: can't open %s: %s\n",
device, strerror(errno));
return NULL;
}
if (enter_via_fet() < 0)
return NULL;
usleep(500000);
/* Show chip info */
if (bsl_xfer(CMD_TX_DATA, 0xff0, NULL, 0x10) < 0) {
fprintf(stderr, "bsl: failed to read chip info\n");
return NULL;
}
if (reply_len < 0x16) {
fprintf(stderr, "bsl: missing chip info\n");
return NULL;
}
print_devid((reply_buf[4] << 8) | reply_buf[5]);
printf("BSL version is %x.%02x\n", reply_buf[14], reply_buf[15]);
return &bsl_device;
}