X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fjtag%2Fdrivers%2Fsysfsgpio.c;h=90e93f5a664b4cf5d4a284ca0c9d021448269b60;hp=05d9a9dc0a248e3a17af34adba45dc394d1721d9;hb=87adca299d7971f1adb5a502be29b9a120678443;hpb=fe52282c37cc0c4ab9863e95ef6970e6fad540b4

diff --git a/src/jtag/drivers/sysfsgpio.c b/src/jtag/drivers/sysfsgpio.c
index 05d9a9dc0a..90e93f5a66 100644
--- a/src/jtag/drivers/sysfsgpio.c
+++ b/src/jtag/drivers/sysfsgpio.c
@@ -12,10 +12,12 @@
  *   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.             *
+ *   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
@@ -56,11 +58,11 @@
 /*
  * 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)
 {
-	return gpio >= 0 && gpio < 1000;
+	return gpio >= 0 && gpio < 10000;
 }
 
 /*
@@ -87,7 +89,7 @@ static int open_write_close(const char *name, const char *valstr)
  */
 static void unexport_sysfs_gpio(int gpio)
 {
-	char gpiostr[4];
+	char gpiostr[5];
 
 	if (!is_gpio_valid(gpio))
 		return;
@@ -111,7 +113,7 @@ static void unexport_sysfs_gpio(int gpio)
 static int setup_sysfs_gpio(int gpio, int is_output, int init_high)
 {
 	char buf[40];
-	char gpiostr[4];
+	char gpiostr[5];
 	int ret;
 
 	if (!is_gpio_valid(gpio))
@@ -139,17 +141,26 @@ static int setup_sysfs_gpio(int gpio, int is_output, int init_high)
 	}
 
 	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)
+	ret = open(buf, O_RDWR | O_NONBLOCK | O_SYNC);
+	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.
@@ -160,6 +171,72 @@ static int tdi_fd = -1;
 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
@@ -167,7 +244,7 @@ static int srst_fd = -1;
  * 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];
 
@@ -180,7 +257,7 @@ static int sysfsgpio_read(void)
 		return 0;
 	}
 
-	return buf[0] == '1';
+	return buf[0] == '0' ? BB_LOW : BB_HIGH;
 }
 
 /*
@@ -189,8 +266,13 @@ static int sysfsgpio_read(void)
  * 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";
 
@@ -199,6 +281,7 @@ static void sysfsgpio_write(int tck, int tms, int tdi)
 	static int last_tdi;
 
 	static int first_time;
+	size_t bytes_written;
 
 	if (!first_time) {
 		last_tck = !tck;
@@ -207,17 +290,30 @@ static void sysfsgpio_write(int tck, int tms, int tdi)
 		first_time = 1;
 	}
 
-	if (tdi != last_tdi)
-		write(tdi_fd, tdi ? &one : &zero, 1);
-	if (tms != last_tms)
-		write(tms_fd, tms ? &one : &zero, 1);
+	if (tdi != last_tdi) {
+		bytes_written = write(tdi_fd, tdi ? &one : &zero, 1);
+		if (bytes_written != 1)
+			LOG_WARNING("writing tdi failed");
+	}
+
+	if (tms != last_tms) {
+		bytes_written = write(tms_fd, tms ? &one : &zero, 1);
+		if (bytes_written != 1)
+			LOG_WARNING("writing tms failed");
+	}
+
 	/* write clk last */
-	if (tck != last_tck)
-		write(tck_fd, tck ? &one : &zero, 1);
+	if (tck != last_tck) {
+		bytes_written = write(tck_fd, tck ? &one : &zero, 1);
+		if (bytes_written != 1)
+			LOG_WARNING("writing tck failed");
+	}
 
 	last_tdi = tdi;
 	last_tms = tms;
 	last_tck = tck;
+
+	return ERROR_OK;
 }
 
 /*
@@ -225,50 +321,30 @@ static void sysfsgpio_write(int tck, int tms, int tdi)
  *
  * (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;
 
 	/* assume active low */
-	if (srst_fd >= 0)
-		write(srst_fd, srst ? &zero : &one, 1);
+	if (srst_fd >= 0) {
+		bytes_written = write(srst_fd, srst ? &zero : &one, 1);
+		if (bytes_written != 1)
+			LOG_WARNING("writing srst failed");
+	}
 
 	/* assume active low */
-	if (trst_fd >= 0)
-		write(trst_fd, trst ? &zero : &one, 1);
-}
-
-/* No speed control is implemented yet */
-static int sysfsgpio_speed(int speed)
-{
-	return ERROR_OK;
-}
-
-static int sysfsgpio_khz(int khz, int *jtag_speed)
-{
-	/* no adaptive clocking */
-	if (khz == 0)
-		return ERROR_FAIL;
-
-	*jtag_speed = 0;
-	return ERROR_OK;
-}
+	if (trst_fd >= 0) {
+		bytes_written = write(trst_fd, trst ? &zero : &one, 1);
+		if (bytes_written != 1)
+			LOG_WARNING("writing trst failed");
+	}
 
-static int sysfsgpio_speed_div(int speed, int *khz)
-{
-	*khz = 1;
 	return ERROR_OK;
 }
 
-/* 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;
-
 COMMAND_HANDLER(sysfsgpio_handle_jtag_gpionums)
 {
 	if (CMD_ARGC == 4) {
@@ -281,7 +357,7 @@ COMMAND_HANDLER(sysfsgpio_handle_jtag_gpionums)
 	}
 
 	command_print(CMD_CTX,
-			"SysfsGPIO nums: tck = %d, tms = %d, tdi = %d, tdi = %d",
+			"SysfsGPIO nums: tck = %d, tms = %d, tdi = %d, tdo = %d",
 			tck_gpio, tms_gpio, tdi_gpio, tdo_gpio);
 
 	return ERROR_OK;
@@ -341,49 +417,110 @@ COMMAND_HANDLER(sysfsgpio_handle_jtag_gpionum_trst)
 	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_CTX,
+			"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_CTX, "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_CTX, "SysfsGPIO num: swdio = %d", swdio_gpio);
+	return ERROR_OK;
+}
+
 static const struct command_registration sysfsgpio_command_handlers[] = {
 	{
 		.name = "sysfsgpio_jtag_nums",
 		.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
 };
@@ -391,14 +528,14 @@ static const struct command_registration sysfsgpio_command_handlers[] = {
 static int sysfsgpio_init(void);
 static int sysfsgpio_quit(void);
 
+static const char * const sysfsgpio_transports[] = { "jtag", "swd", NULL };
+
 struct jtag_interface sysfsgpio_interface = {
 	.name = "sysfsgpio",
 	.supported = DEBUG_CAP_TMS_SEQ,
 	.execute_queue = bitbang_execute_queue,
-	.transports = jtag_only,
-	.speed = sysfsgpio_speed,
-	.khz = sysfsgpio_khz,
-	.speed_div = sysfsgpio_speed_div,
+	.transports = sysfsgpio_transports,
+	.swd = &bitbang_swd,
 	.commands = sysfsgpio_command_handlers,
 	.init = sysfsgpio_init,
 	.quit = sysfsgpio_quit,
@@ -408,6 +545,8 @@ 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
 };
 
@@ -430,65 +569,112 @@ static void cleanup_all_fds(void)
 	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 0;
+	if (!is_gpio_valid(tms_gpio))
+		return 0;
+	if (!is_gpio_valid(tdi_gpio))
+		return 0;
+	if (!is_gpio_valid(tdo_gpio))
+		return 0;
+	return 1;
+}
+
+static bool sysfsgpio_swd_mode_possible(void)
+{
+	if (!is_gpio_valid(swclk_gpio))
+		return 0;
+	if (!is_gpio_valid(swdio_gpio))
+		return 0;
+	return 1;
 }
 
 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*/
-	trst_fd = setup_sysfs_gpio(trst_gpio, 1, 1);
-	if (trst_gpio > 0 && trst_fd < 0)
-		goto out_error;
+	if (trst_gpio >= 0) {
+		trst_fd = setup_sysfs_gpio(trst_gpio, 1, 1);
+		if (trst_fd < 0)
+			goto out_error;
+	}
 
 	/* assume active low*/
-	srst_fd = setup_sysfs_gpio(srst_gpio, 1, 1);
-	if (srst_gpio > 0 && srst_fd < 0)
-		goto out_error;
+	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;
+	}
+
+	if (sysfsgpio_swd_mode_possible()) {
+		if (swd_mode)
+			bitbang_swd_switch_seq(JTAG_TO_SWD);
+		else
+			bitbang_swd_switch_seq(SWD_TO_JTAG);
+	}
 
 	return ERROR_OK;