adapter: add command "adapter [de]assert srst|trst [[de]assert srst|trst]"

Inspired from http://openocd.zylin.com/#/c/3720/1

Add commands to control the adapter's signals srst and trst.
Add macros for the flag's values assert/deassert to make clear what
they mean and to propose a uniform set of values across the code.

Change-Id: Ia8b13f4ded892942916cad7bda49540a896e7218
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/5277
Tested-by: jenkins

src/jtag/adapter.c

@@ -411,6 +411,92 @@ COMMAND_HANDLER(handle_adapter_khz_command)
 	return retval;
 }
 
+COMMAND_HANDLER(handle_adapter_reset_de_assert)
+{
+	enum values {
+		VALUE_UNDEFINED = -1,
+		VALUE_DEASSERT  = 0,
+		VALUE_ASSERT    = 1,
+	};
+	enum values value;
+	enum values srst = VALUE_UNDEFINED;
+	enum values trst = VALUE_UNDEFINED;
+	enum reset_types jtag_reset_config = jtag_get_reset_config();
+	char *signal;
+
+	if (CMD_ARGC == 0) {
+		if (transport_is_jtag()) {
+			if (jtag_reset_config & RESET_HAS_TRST)
+				signal = jtag_get_trst() ? "asserted" : "deasserted";
+			else
+				signal = "not present";
+			command_print(CMD, "trst %s", signal);
+		}
+
+		if (jtag_reset_config & RESET_HAS_SRST)
+			signal = jtag_get_srst() ? "asserted" : "deasserted";
+		else
+			signal = "not present";
+		command_print(CMD, "srst %s", signal);
+
+		return ERROR_OK;
+	}
+
+	if (CMD_ARGC != 1 && CMD_ARGC != 3)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	value = (strcmp(CMD_NAME, "assert") == 0) ? VALUE_ASSERT : VALUE_DEASSERT;
+	if (strcmp(CMD_ARGV[0], "srst") == 0)
+		srst = value;
+	else if (strcmp(CMD_ARGV[0], "trst") == 0)
+		trst = value;
+	else
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	if (CMD_ARGC == 3) {
+		if (strcmp(CMD_ARGV[1], "assert") == 0)
+			value = VALUE_ASSERT;
+		else if (strcmp(CMD_ARGV[1], "deassert") == 0)
+			value = VALUE_DEASSERT;
+		else
+			return ERROR_COMMAND_SYNTAX_ERROR;
+
+		if (strcmp(CMD_ARGV[2], "srst") == 0 && srst == VALUE_UNDEFINED)
+			srst = value;
+		else if (strcmp(CMD_ARGV[2], "trst") == 0 && trst == VALUE_UNDEFINED)
+			trst = value;
+		else
+			return ERROR_COMMAND_SYNTAX_ERROR;
+	}
+
+	if (trst == VALUE_UNDEFINED) {
+		if (transport_is_jtag())
+			trst = jtag_get_trst() ? VALUE_ASSERT : VALUE_DEASSERT;
+		else
+			trst = VALUE_DEASSERT; /* unused, safe value */
+	}
+
+	if (srst == VALUE_UNDEFINED) {
+		if (jtag_reset_config & RESET_HAS_SRST)
+			srst = jtag_get_srst() ? VALUE_ASSERT : VALUE_DEASSERT;
+		else
+			srst = VALUE_DEASSERT; /* unused, safe value */
+	}
+
+	if (trst == VALUE_ASSERT && !transport_is_jtag()) {
+		LOG_ERROR("transport has no trst signal");
+		return ERROR_FAIL;
+	}
+
+	if (srst == VALUE_ASSERT && !(jtag_reset_config & RESET_HAS_SRST)) {
+		LOG_ERROR("adapter has no srst signal");
+		return ERROR_FAIL;
+	}
+
+	return adapter_resets((trst == VALUE_DEASSERT) ? TRST_DEASSERT : TRST_ASSERT,
+						  (srst == VALUE_DEASSERT) ? SRST_DEASSERT : SRST_ASSERT);
+}
+
 #ifndef HAVE_JTAG_MINIDRIVER_H
 #ifdef HAVE_LIBUSB_GET_PORT_NUMBERS
 COMMAND_HANDLER(handle_usb_location_command)
@@ -448,6 +534,20 @@ static const struct command_registration adapter_command_handlers[] = {
 		.chain = adapter_usb_command_handlers,
 	},
 #endif /* MINIDRIVER */
+	{
+		.name = "assert",
+		.handler = handle_adapter_reset_de_assert,
+		.mode = COMMAND_EXEC,
+		.help = "Controls SRST and TRST lines.",
+		.usage = "|deassert [srst|trst [assert|deassert srst|trst]]",
+	},
+	{
+		.name = "deassert",
+		.handler = handle_adapter_reset_de_assert,
+		.mode = COMMAND_EXEC,
+		.help = "Controls SRST and TRST lines.",
+		.usage = "|assert [srst|trst [deassert|assert srst|trst]]",
+	},
 	COMMAND_REGISTRATION_DONE
 };
 

src/jtag/core.c

@@ -35,6 +35,8 @@
 #include "interface.h"
 #include <transport/transport.h>
 #include <helper/jep106.h>
+#include <jtag/hla/hla_transport.h>
+#include <jtag/hla/hla_interface.h>
 
 #ifdef HAVE_STRINGS_H
 #include <strings.h>
@@ -1888,6 +1890,57 @@ bool transport_is_jtag(void)
 	return get_current_transport() == &jtag_transport;
 }
 
+int adapter_resets(int trst, int srst)
+{
+	if (get_current_transport() == NULL) {
+		LOG_ERROR("transport is not selected");
+		return ERROR_FAIL;
+	}
+
+	if (transport_is_jtag()) {
+		if (srst == SRST_ASSERT && !(jtag_reset_config & RESET_HAS_SRST)) {
+			LOG_ERROR("adapter has no srst signal");
+			return ERROR_FAIL;
+		}
+
+		/* adapters without trst signal will eventually use tlr sequence */
+		jtag_add_reset(trst, srst);
+		return ERROR_OK;
+	} else if (transport_is_swd()) {
+		if (trst == TRST_ASSERT) {
+			LOG_ERROR("transport swd has no trst signal");
+			return ERROR_FAIL;
+		}
+
+		if (srst == SRST_ASSERT && !(jtag_reset_config & RESET_HAS_SRST)) {
+			LOG_ERROR("adapter has no srst signal");
+			return ERROR_FAIL;
+		}
+		swd_add_reset(srst);
+		return ERROR_OK;
+	} else if (transport_is_hla()) {
+		if (trst == TRST_ASSERT) {
+			LOG_ERROR("transport %s has no trst signal",
+				get_current_transport()->name);
+			return ERROR_FAIL;
+		}
+
+		if (srst == SRST_ASSERT && !(jtag_reset_config & RESET_HAS_SRST)) {
+			LOG_ERROR("adapter has no srst signal");
+			return ERROR_FAIL;
+		}
+		return hl_interface_reset(srst);
+	}
+
+	if (trst == TRST_DEASSERT && srst == SRST_DEASSERT)
+		return ERROR_OK;
+
+	LOG_ERROR("reset is not supported on transport %s",
+		get_current_transport()->name);
+
+	return ERROR_FAIL;
+}
+
 void adapter_assert_reset(void)
 {
 	if (transport_is_jtag()) {

src/jtag/hla/hla_interface.c

@@ -148,6 +148,21 @@ int hl_interface_init_reset(void)
 	return ERROR_OK;
 }
 
+/* FIXME: hla abuses of jtag_add_reset() to track srst status and for timings */
+int hl_interface_reset(int srst)
+{
+	int result;
+
+	if (srst == 1) {
+		jtag_add_reset(0, 1);
+		result = hl_if.layout->api->assert_srst(hl_if.handle, 0);
+	} else {
+		result = hl_if.layout->api->assert_srst(hl_if.handle, 1);
+		jtag_add_reset(0, 0);
+	}
+	return result;
+}
+
 static int hl_interface_khz(int khz, int *jtag_speed)
 {
 	if (hl_if.layout->api->speed == NULL)

src/jtag/hla/hla_interface.h

@@ -67,4 +67,13 @@ int hl_interface_init_target(struct target *t);
 int hl_interface_init_reset(void);
 int hl_interface_override_target(const char **targetname);
 
+#if BUILD_HLADAPTER == 1
+int hl_interface_reset(int srst);
+#else
+static inline int hl_interface_reset(int srst)
+{
+	return ERROR_OK;
+}
+#endif
+
 #endif /* OPENOCD_JTAG_HLA_HLA_INTERFACE_H */

src/jtag/interface.h

@@ -326,6 +326,7 @@ struct jtag_interface {
 
 extern const char * const jtag_only[];
 
+int adapter_resets(int assert_trst, int assert_srst);
 void adapter_assert_reset(void);
 void adapter_deassert_reset(void);
 int adapter_config_trace(bool enabled, enum tpiu_pin_protocol pin_protocol,

src/jtag/jtag.h

@@ -76,6 +76,14 @@ typedef enum tap_state {
 #endif
 } tap_state_t;
 
+/**
+ * Defines arguments for reset functions
+ */
+#define SRST_DEASSERT   0
+#define SRST_ASSERT     1
+#define TRST_DEASSERT   0
+#define TRST_ASSERT     1
+
 /**
  * Function tap_state_name
  * Returns a string suitable for display representing the JTAG tap_state