* 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 Street, Fifth Floor, Boston, MA 02110-1301 USA. *
+ * along with this program. If not, see <http://www.gnu.org/licenses/>. *
***************************************************************************/
+
+/* 2014-12: Addition of the SWD protocol support is based on the initial work
+ * on bcm2835gpio.c by Paul Fertser and modifications by Jean-Christian de Rivaz. */
+
/**
* @file
* This driver implements a bitbang jtag interface using gpio lines via
#include "config.h"
#endif
+#include <helper/time_support.h>
#include <jtag/interface.h>
#include "bitbang.h"
/*
* Helper func to determine if gpio number valid
*
- * Assume here that there will be less than 1000 gpios on a system
+ * Assume here that there will be less than 10000 gpios on a system
*/
-static int is_gpio_valid(int gpio)
+static bool is_gpio_valid(int gpio)
{
- return gpio >= 0 && gpio < 1000;
+ return gpio >= 0 && gpio < 10000;
}
/*
*/
static void unexport_sysfs_gpio(int gpio)
{
- char gpiostr[4];
+ char gpiostr[5];
if (!is_gpio_valid(gpio))
return;
snprintf(gpiostr, sizeof(gpiostr), "%d", gpio);
if (open_write_close("/sys/class/gpio/unexport", gpiostr) < 0)
LOG_ERROR("Couldn't unexport gpio %d", gpio);
-
- return;
}
/*
*/
static int setup_sysfs_gpio(int gpio, int is_output, int init_high)
{
+ struct timeval timeout, now;
char buf[40];
- char gpiostr[4];
+ char gpiostr[5];
int ret;
if (!is_gpio_valid(gpio))
}
}
+ gettimeofday(&timeout, NULL);
+ timeval_add_time(&timeout, 0, 500000);
+
snprintf(buf, sizeof(buf), "/sys/class/gpio/gpio%d/direction", gpio);
- ret = open_write_close(buf, is_output ? (init_high ? "high" : "low") : "in");
+ for (;;) {
+ ret = open_write_close(buf, is_output ? (init_high ? "high" : "low") : "in");
+ if (ret >= 0 || errno != EACCES)
+ break;
+ gettimeofday(&now, NULL);
+ if (timeval_compare(&now, &timeout) >= 0)
+ break;
+ jtag_sleep(10000);
+ }
if (ret < 0) {
LOG_ERROR("Couldn't set direction for gpio %d", gpio);
perror("sysfsgpio: ");
}
snprintf(buf, sizeof(buf), "/sys/class/gpio/gpio%d/value", gpio);
- if (is_output)
- ret = open(buf, O_WRONLY | O_NONBLOCK | O_SYNC);
- else
- ret = open(buf, O_RDONLY | O_NONBLOCK | O_SYNC);
-
- if (ret < 0)
+ for (;;) {
+ ret = open(buf, O_RDWR | O_NONBLOCK | O_SYNC);
+ if (ret >= 0 || errno != EACCES)
+ break;
+ gettimeofday(&now, NULL);
+ if (timeval_compare(&now, &timeout) >= 0)
+ break;
+ jtag_sleep(10000);
+ }
+ if (ret < 0) {
+ LOG_ERROR("Couldn't open value for gpio %d", gpio);
+ perror("sysfsgpio: ");
unexport_sysfs_gpio(gpio);
+ }
return ret;
}
+/* gpio numbers for each gpio. Negative values are invalid */
+static int tck_gpio = -1;
+static int tms_gpio = -1;
+static int tdi_gpio = -1;
+static int tdo_gpio = -1;
+static int trst_gpio = -1;
+static int srst_gpio = -1;
+static int swclk_gpio = -1;
+static int swdio_gpio = -1;
+
/*
* file descriptors for /sys/class/gpio/gpioXX/value
* Set up during init.
static int tdo_fd = -1;
static int trst_fd = -1;
static int srst_fd = -1;
+static int swclk_fd = -1;
+static int swdio_fd = -1;
+
+static int last_swclk;
+static int last_swdio;
+static bool last_stored;
+static bool swdio_input;
+
+static void sysfsgpio_swdio_drive(bool is_output)
+{
+ char buf[40];
+ int ret;
+
+ snprintf(buf, sizeof(buf), "/sys/class/gpio/gpio%d/direction", swdio_gpio);
+ ret = open_write_close(buf, is_output ? "high" : "in");
+ if (ret < 0) {
+ LOG_ERROR("Couldn't set direction for gpio %d", swdio_gpio);
+ perror("sysfsgpio: ");
+ }
+
+ last_stored = false;
+ swdio_input = !is_output;
+}
+
+static int sysfsgpio_swdio_read(void)
+{
+ char buf[1];
+
+ /* important to seek to signal sysfs of new read */
+ lseek(swdio_fd, 0, SEEK_SET);
+ int ret = read(swdio_fd, &buf, sizeof(buf));
+
+ if (ret < 0) {
+ LOG_WARNING("reading swdio failed");
+ return 0;
+ }
+
+ return buf[0] != '0';
+}
+
+static void sysfsgpio_swdio_write(int swclk, int swdio)
+{
+ const char one[] = "1";
+ const char zero[] = "0";
+
+ size_t bytes_written;
+
+ if (!swdio_input) {
+ if (!last_stored || (swdio != last_swdio)) {
+ bytes_written = write(swdio_fd, swdio ? &one : &zero, 1);
+ if (bytes_written != 1)
+ LOG_WARNING("writing swdio failed");
+ }
+ }
+
+ /* write swclk last */
+ if (!last_stored || (swclk != last_swclk)) {
+ bytes_written = write(swclk_fd, swclk ? &one : &zero, 1);
+ if (bytes_written != 1)
+ LOG_WARNING("writing swclk failed");
+ }
+
+ last_swdio = swdio;
+ last_swclk = swclk;
+ last_stored = true;
+}
/*
* Bitbang interface read of TDO
* The sysfs value will read back either '0' or '1'. The trick here is to call
* lseek to bypass buffering in the sysfs kernel driver.
*/
-static int sysfsgpio_read(void)
+static bb_value_t sysfsgpio_read(void)
{
char buf[1];
return 0;
}
- return buf[0] == '1';
+ return buf[0] == '0' ? BB_LOW : BB_HIGH;
}
/*
* Seeing as this is the only function where the outputs are changed,
* we can cache the old value to avoid needlessly writing it.
*/
-static void sysfsgpio_write(int tck, int tms, int tdi)
+static int sysfsgpio_write(int tck, int tms, int tdi)
{
+ if (swd_mode) {
+ sysfsgpio_swdio_write(tck, tdi);
+ return ERROR_OK;
+ }
+
const char one[] = "1";
const char zero[] = "0";
last_tdi = tdi;
last_tms = tms;
last_tck = tck;
+
+ return ERROR_OK;
}
/*
*
* (1) assert or (0) deassert reset lines
*/
-static void sysfsgpio_reset(int trst, int srst)
+static int sysfsgpio_reset(int trst, int srst)
{
+ LOG_DEBUG("sysfsgpio_reset");
const char one[] = "1";
const char zero[] = "0";
size_t bytes_written;
if (bytes_written != 1)
LOG_WARNING("writing trst failed");
}
-}
-/* gpio numbers for each gpio. Negative values are invalid */
-static int tck_gpio = -1;
-static int tms_gpio = -1;
-static int tdi_gpio = -1;
-static int tdo_gpio = -1;
-static int trst_gpio = -1;
-static int srst_gpio = -1;
+ return ERROR_OK;
+}
COMMAND_HANDLER(sysfsgpio_handle_jtag_gpionums)
{
return ERROR_COMMAND_SYNTAX_ERROR;
}
- command_print(CMD_CTX,
- "SysfsGPIO nums: tck = %d, tms = %d, tdi = %d, tdi = %d",
+ command_print(CMD,
+ "SysfsGPIO nums: tck = %d, tms = %d, tdi = %d, tdo = %d",
tck_gpio, tms_gpio, tdi_gpio, tdo_gpio);
return ERROR_OK;
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tck_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: tck = %d", tck_gpio);
+ command_print(CMD, "SysfsGPIO num: tck = %d", tck_gpio);
return ERROR_OK;
}
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tms_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: tms = %d", tms_gpio);
+ command_print(CMD, "SysfsGPIO num: tms = %d", tms_gpio);
return ERROR_OK;
}
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdo_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: tdo = %d", tdo_gpio);
+ command_print(CMD, "SysfsGPIO num: tdo = %d", tdo_gpio);
return ERROR_OK;
}
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], tdi_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: tdi = %d", tdi_gpio);
+ command_print(CMD, "SysfsGPIO num: tdi = %d", tdi_gpio);
return ERROR_OK;
}
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], srst_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: srst = %d", srst_gpio);
+ command_print(CMD, "SysfsGPIO num: srst = %d", srst_gpio);
return ERROR_OK;
}
if (CMD_ARGC == 1)
COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], trst_gpio);
- command_print(CMD_CTX, "SysfsGPIO num: trst = %d", trst_gpio);
+ command_print(CMD, "SysfsGPIO num: trst = %d", trst_gpio);
+ return ERROR_OK;
+}
+
+COMMAND_HANDLER(sysfsgpio_handle_swd_gpionums)
+{
+ if (CMD_ARGC == 2) {
+ COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
+ COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], swdio_gpio);
+ } else if (CMD_ARGC != 0) {
+ return ERROR_COMMAND_SYNTAX_ERROR;
+ }
+
+ command_print(CMD,
+ "SysfsGPIO nums: swclk = %d, swdio = %d",
+ swclk_gpio, swdio_gpio);
+
+ return ERROR_OK;
+}
+
+COMMAND_HANDLER(sysfsgpio_handle_swd_gpionum_swclk)
+{
+ if (CMD_ARGC == 1)
+ COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swclk_gpio);
+
+ command_print(CMD, "SysfsGPIO num: swclk = %d", swclk_gpio);
+ return ERROR_OK;
+}
+
+COMMAND_HANDLER(sysfsgpio_handle_swd_gpionum_swdio)
+{
+ if (CMD_ARGC == 1)
+ COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], swdio_gpio);
+
+ command_print(CMD, "SysfsGPIO num: swdio = %d", swdio_gpio);
return ERROR_OK;
}
.handler = &sysfsgpio_handle_jtag_gpionums,
.mode = COMMAND_CONFIG,
.help = "gpio numbers for tck, tms, tdi, tdo. (in that order)",
- .usage = "(tck tms tdi tdo)* ",
+ .usage = "[tck tms tdi tdo]",
},
{
.name = "sysfsgpio_tck_num",
.handler = &sysfsgpio_handle_jtag_gpionum_tck,
.mode = COMMAND_CONFIG,
.help = "gpio number for tck.",
+ .usage = "[tck]",
},
{
.name = "sysfsgpio_tms_num",
.handler = &sysfsgpio_handle_jtag_gpionum_tms,
.mode = COMMAND_CONFIG,
.help = "gpio number for tms.",
+ .usage = "[tms]",
},
{
.name = "sysfsgpio_tdo_num",
.handler = &sysfsgpio_handle_jtag_gpionum_tdo,
.mode = COMMAND_CONFIG,
.help = "gpio number for tdo.",
+ .usage = "[tdo]",
},
{
.name = "sysfsgpio_tdi_num",
.handler = &sysfsgpio_handle_jtag_gpionum_tdi,
.mode = COMMAND_CONFIG,
.help = "gpio number for tdi.",
+ .usage = "[tdi]",
},
{
.name = "sysfsgpio_srst_num",
.handler = &sysfsgpio_handle_jtag_gpionum_srst,
.mode = COMMAND_CONFIG,
.help = "gpio number for srst.",
+ .usage = "[srst]",
},
{
.name = "sysfsgpio_trst_num",
.handler = &sysfsgpio_handle_jtag_gpionum_trst,
.mode = COMMAND_CONFIG,
.help = "gpio number for trst.",
+ .usage = "[trst]",
+ },
+ {
+ .name = "sysfsgpio_swd_nums",
+ .handler = &sysfsgpio_handle_swd_gpionums,
+ .mode = COMMAND_CONFIG,
+ .help = "gpio numbers for swclk, swdio. (in that order)",
+ .usage = "[swclk swdio]",
+ },
+ {
+ .name = "sysfsgpio_swclk_num",
+ .handler = &sysfsgpio_handle_swd_gpionum_swclk,
+ .mode = COMMAND_CONFIG,
+ .help = "gpio number for swclk.",
+ .usage = "[swclk]",
+ },
+ {
+ .name = "sysfsgpio_swdio_num",
+ .handler = &sysfsgpio_handle_swd_gpionum_swdio,
+ .mode = COMMAND_CONFIG,
+ .help = "gpio number for swdio.",
+ .usage = "[swdio]",
},
COMMAND_REGISTRATION_DONE
};
static int sysfsgpio_init(void);
static int sysfsgpio_quit(void);
-struct jtag_interface sysfsgpio_interface = {
- .name = "sysfsgpio",
+static const char * const sysfsgpio_transports[] = { "jtag", "swd", NULL };
+
+static struct jtag_interface sysfsgpio_interface = {
.supported = DEBUG_CAP_TMS_SEQ,
.execute_queue = bitbang_execute_queue,
- .transports = jtag_only,
+};
+
+struct adapter_driver sysfsgpio_adapter_driver = {
+ .name = "sysfsgpio",
+ .transports = sysfsgpio_transports,
.commands = sysfsgpio_command_handlers,
+
.init = sysfsgpio_init,
.quit = sysfsgpio_quit,
+ .reset = sysfsgpio_reset,
+
+ .jtag_ops = &sysfsgpio_interface,
+ .swd_ops = &bitbang_swd,
};
static struct bitbang_interface sysfsgpio_bitbang = {
.read = sysfsgpio_read,
.write = sysfsgpio_write,
- .reset = sysfsgpio_reset,
+ .swdio_read = sysfsgpio_swdio_read,
+ .swdio_drive = sysfsgpio_swdio_drive,
.blink = 0
};
cleanup_fd(tdo_fd, tdo_gpio);
cleanup_fd(trst_fd, trst_gpio);
cleanup_fd(srst_fd, srst_gpio);
+ cleanup_fd(swclk_fd, swclk_gpio);
+ cleanup_fd(swdio_fd, swdio_gpio);
+}
+
+static bool sysfsgpio_jtag_mode_possible(void)
+{
+ if (!is_gpio_valid(tck_gpio))
+ return false;
+ if (!is_gpio_valid(tms_gpio))
+ return false;
+ if (!is_gpio_valid(tdi_gpio))
+ return false;
+ if (!is_gpio_valid(tdo_gpio))
+ return false;
+ return true;
+}
+
+static bool sysfsgpio_swd_mode_possible(void)
+{
+ if (!is_gpio_valid(swclk_gpio))
+ return false;
+ if (!is_gpio_valid(swdio_gpio))
+ return false;
+ return true;
}
static int sysfsgpio_init(void)
{
bitbang_interface = &sysfsgpio_bitbang;
- LOG_INFO("SysfsGPIO JTAG bitbang driver");
-
- if (!(is_gpio_valid(tck_gpio)
- && is_gpio_valid(tms_gpio)
- && is_gpio_valid(tdi_gpio)
- && is_gpio_valid(tdo_gpio))) {
- if (!is_gpio_valid(tck_gpio))
- LOG_ERROR("gpio num for tck is invalid");
- if (!is_gpio_valid(tms_gpio))
- LOG_ERROR("gpio num for tms is invalid");
- if (!is_gpio_valid(tdo_gpio))
- LOG_ERROR("gpio num for tdo is invalid");
- if (!is_gpio_valid(tdi_gpio))
- LOG_ERROR("gpio num for tdi is invalid");
-
- LOG_ERROR("Require tck, tms, tdi and tdo gpios to all be specified");
+ LOG_INFO("SysfsGPIO JTAG/SWD bitbang driver");
+
+ if (sysfsgpio_jtag_mode_possible()) {
+ if (sysfsgpio_swd_mode_possible())
+ LOG_INFO("JTAG and SWD modes enabled");
+ else
+ LOG_INFO("JTAG only mode enabled (specify swclk and swdio gpio to add SWD mode)");
+ } else if (sysfsgpio_swd_mode_possible()) {
+ LOG_INFO("SWD only mode enabled (specify tck, tms, tdi and tdo gpios to add JTAG mode)");
+ } else {
+ LOG_ERROR("Require tck, tms, tdi and tdo gpios for JTAG mode and/or swclk and swdio gpio for SWD mode");
return ERROR_JTAG_INIT_FAILED;
}
- if (!is_gpio_valid(trst_gpio) && !is_gpio_valid(srst_gpio)) {
- LOG_ERROR("Require at least one of trst or srst gpios to be specified");
- return ERROR_JTAG_INIT_FAILED;
- }
/*
* Configure TDO as an input, and TDI, TCK, TMS, TRST, SRST
* as outputs. Drive TDI and TCK low, and TMS/TRST/SRST high.
+ * For SWD, SWCLK and SWDIO are configures as output high.
*/
- tck_fd = setup_sysfs_gpio(tck_gpio, 1, 0);
- if (tck_fd < 0)
- goto out_error;
+ if (tck_gpio >= 0) {
+ tck_fd = setup_sysfs_gpio(tck_gpio, 1, 0);
+ if (tck_fd < 0)
+ goto out_error;
+ }
- tms_fd = setup_sysfs_gpio(tms_gpio, 1, 1);
- if (tms_fd < 0)
- goto out_error;
+ if (tms_gpio >= 0) {
+ tms_fd = setup_sysfs_gpio(tms_gpio, 1, 1);
+ if (tms_fd < 0)
+ goto out_error;
+ }
- tdi_fd = setup_sysfs_gpio(tdi_gpio, 1, 0);
- if (tdi_fd < 0)
- goto out_error;
+ if (tdi_gpio >= 0) {
+ tdi_fd = setup_sysfs_gpio(tdi_gpio, 1, 0);
+ if (tdi_fd < 0)
+ goto out_error;
+ }
- tdo_fd = setup_sysfs_gpio(tdo_gpio, 0, 0);
- if (tdo_fd < 0)
- goto out_error;
+ if (tdo_gpio >= 0) {
+ tdo_fd = setup_sysfs_gpio(tdo_gpio, 0, 0);
+ if (tdo_fd < 0)
+ goto out_error;
+ }
/* assume active low*/
- if (trst_gpio > 0) {
+ if (trst_gpio >= 0) {
trst_fd = setup_sysfs_gpio(trst_gpio, 1, 1);
if (trst_fd < 0)
goto out_error;
}
/* assume active low*/
- if (srst_gpio > 0) {
+ if (srst_gpio >= 0) {
srst_fd = setup_sysfs_gpio(srst_gpio, 1, 1);
if (srst_fd < 0)
goto out_error;
}
+ if (swclk_gpio >= 0) {
+ swclk_fd = setup_sysfs_gpio(swclk_gpio, 1, 0);
+ if (swclk_fd < 0)
+ goto out_error;
+ }
+
+ if (swdio_gpio >= 0) {
+ swdio_fd = setup_sysfs_gpio(swdio_gpio, 1, 0);
+ if (swdio_fd < 0)
+ goto out_error;
+ }
+
return ERROR_OK;
out_error:
cleanup_all_fds();
return ERROR_OK;
}
-