adi_v5_dapdirect: add support for adapter drivers that provide DAP API

Some high level adapters, like STLINK-V3 and new firmware for
ST-Link/V2, provide API to directly access the DAP registers
hiding the details of the physical transport JTAG or SWD.
OpenOCD has already the intermediate API in struct dap_ops that
are suitable for such adapters, but are not exposed to the
adapter drivers.

Add in struct adapter_driver two independent struct dap_ops for
the cases of physical JTAG and SWD transport.
Add new transport names "dapdirect_jtag" and "dapdirect_swd", to
be used by the drivers that provide one or both DAP API.
Add the necessarily glue in target/adi_v5_dapdirect.c

Change-Id: I2bb8e3a80fba750f2c218d877cfa5888428e3c28
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/4903
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/jtag/core.c

@@ -2052,7 +2052,8 @@ int adapter_assert_reset(void)
 		else
 			jtag_add_reset(0, 1);
 		return ERROR_OK;
-	} else if (transport_is_swd() || transport_is_hla())
+	} else if (transport_is_swd() || transport_is_hla() ||
+			   transport_is_dapdirect_jtag() || transport_is_dapdirect_swd())
 		return adapter_system_reset(1);
 	else if (get_current_transport() != NULL)
 		LOG_ERROR("reset is not supported on %s",
@@ -2067,7 +2068,8 @@ int adapter_deassert_reset(void)
 	if (transport_is_jtag()) {
 		jtag_add_reset(0, 0);
 		return ERROR_OK;
-	} else if (transport_is_swd() || transport_is_hla())
+	} else if (transport_is_swd() || transport_is_hla() ||
+			 transport_is_dapdirect_jtag() || transport_is_dapdirect_swd())
 		return adapter_system_reset(0);
 	else if (get_current_transport() != NULL)
 		LOG_ERROR("reset is not supported on %s",

src/jtag/interface.h

@@ -351,6 +351,12 @@ struct adapter_driver {
 
 	/** Low-level SWD APIs */
 	const struct swd_driver *swd_ops;
+
+	/* DAP APIs over JTAG transport */
+	const struct dap_ops *dap_jtag_ops;
+
+	/* DAP APIs over SWD transport */
+	const struct dap_ops *dap_swd_ops;
 };
 
 extern const char * const jtag_only[];

src/target/Makefile.am

@@ -98,6 +98,7 @@ ARM_DEBUG_SRC = \
 	%D%/arm_dap.c \
 	%D%/armv7a_cache.c \
 	%D%/armv7a_cache_l2x.c \
+	%D%/adi_v5_dapdirect.c \
 	%D%/adi_v5_jtag.c \
 	%D%/adi_v5_swd.c \
 	%D%/embeddedice.c \

src/target/adi_v5_dapdirect.c

@@ -0,0 +1,223 @@
+/*
+ * Copyright (C) 2019, STMicroelectronics - All Rights Reserved
+ * Author(s): Antonio Borneo <borneo.antonio@gmail.com> for STMicroelectronics
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @file
+ * Utilities to support in-circuit debuggers that provide APIs to access
+ * directly ARM DAP, hiding the access to the underlining transport used
+ * for the physical connection (either JTAG or SWD).
+ * E.g. STMicroelectronics ST-Link/V2 (from version V2J24) and STLINK-V3.
+ *
+ * Single-DAP support only.
+ *
+ * For details, see "ARM IHI 0031A"
+ * ARM Debug Interface v5 Architecture Specification
+ *
+ * FIXME: in JTAG mode, trst is not managed
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <jtag/interface.h>
+#include <jtag/tcl.h>
+#include <transport/transport.h>
+
+COMMAND_HANDLER(dapdirect_jtag_empty_command)
+{
+	LOG_DEBUG("dapdirect_jtag_empty_command(\"%s\")", CMD_NAME);
+
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(dapdirect_jtag_reset_command)
+{
+	enum reset_types jtag_reset_config = jtag_get_reset_config();
+
+	/*
+	 * in case the adapter has not already handled asserting srst
+	 * we will attempt it again
+	 */
+	if (jtag_reset_config & RESET_CNCT_UNDER_SRST) {
+		if (jtag_reset_config & RESET_SRST_NO_GATING) {
+			adapter_assert_reset();
+			return ERROR_OK;
+		}
+		LOG_WARNING("\'srst_nogate\' reset_config option is required");
+	}
+	adapter_deassert_reset();
+	return ERROR_OK;
+}
+
+static const struct command_registration dapdirect_jtag_subcommand_handlers[] = {
+	{
+		.name = "newtap",
+		.mode = COMMAND_CONFIG,
+		.jim_handler = jim_jtag_newtap,
+		.help = "declare a new TAP"
+	},
+	{
+		.name = "init",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = ""
+	},
+	{
+		.name = "arp_init",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = ""
+	},
+	{
+		.name = "arp_init-reset",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_reset_command,
+		.usage = ""
+	},
+	{
+		.name = "tapisenabled",
+		.mode = COMMAND_EXEC,
+		.jim_handler = jim_jtag_tap_enabler,
+	},
+	{
+		.name = "tapenable",
+		.mode = COMMAND_EXEC,
+		.jim_handler = jim_jtag_tap_enabler,
+	},
+	{
+		.name = "tapdisable",
+		.mode = COMMAND_EXEC,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = "",
+	},
+	{
+		.name = "configure",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = "",
+	},
+	{
+		.name = "cget",
+		.mode = COMMAND_EXEC,
+		.jim_handler = jim_jtag_configure,
+	},
+	{
+		.name = "names",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = "",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration dapdirect_jtag_handlers[] = {
+	{
+		.name = "jtag",
+		.mode = COMMAND_ANY,
+		.chain = dapdirect_jtag_subcommand_handlers,
+		.usage = "",
+	},
+	{
+		.name = "jtag_ntrst_delay",
+		.mode = COMMAND_ANY,
+		.handler = dapdirect_jtag_empty_command,
+		.usage = "",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration dapdirect_swd_subcommand_handlers[] = {
+	{
+		.name = "newdap",
+		.mode = COMMAND_CONFIG,
+		.jim_handler = jim_jtag_newtap,
+		.help = "declare a new SWD DAP",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration dapdirect_swd_handlers[] = {
+	{
+		.name = "swd",
+		.mode = COMMAND_ANY,
+		.help = "SWD command group",
+		.usage = "",
+		.chain = dapdirect_swd_subcommand_handlers,
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static int dapdirect_jtag_select(struct command_context *ctx)
+{
+	LOG_DEBUG("dapdirect_jtag_select()");
+
+	return register_commands(ctx, NULL, dapdirect_jtag_handlers);
+}
+
+static int dapdirect_swd_select(struct command_context *ctx)
+{
+	LOG_DEBUG("dapdirect_swd_select()");
+
+	return register_commands(ctx, NULL, dapdirect_swd_handlers);
+}
+
+static int dapdirect_init(struct command_context *ctx)
+{
+	LOG_DEBUG("dapdirect_init()");
+
+	adapter_deassert_reset();
+	return ERROR_OK;
+}
+
+static struct transport dapdirect_jtag_transport = {
+	.name = "dapdirect_jtag",
+	.select = dapdirect_jtag_select,
+	.init = dapdirect_init,
+};
+
+static struct transport dapdirect_swd_transport = {
+	.name = "dapdirect_swd",
+	.select = dapdirect_swd_select,
+	.init = dapdirect_init,
+};
+
+static void dapdirect_constructor(void) __attribute__((constructor));
+static void dapdirect_constructor(void)
+{
+	transport_register(&dapdirect_jtag_transport);
+	transport_register(&dapdirect_swd_transport);
+}
+
+/**
+ * Returns true if the current debug session
+ * is using JTAG as its transport.
+ */
+bool transport_is_dapdirect_jtag(void)
+{
+	return get_current_transport() == &dapdirect_jtag_transport;
+}
+
+/**
+ * Returns true if the current debug session
+ * is using SWD as its transport.
+ */
+bool transport_is_dapdirect_swd(void)
+{
+	return get_current_transport() == &dapdirect_swd_transport;
+}

src/target/arm_dap.c

@@ -119,6 +119,10 @@ static int dap_init_all(void)
 		if (transport_is_swd()) {
 			dap->ops = &swd_dap_ops;
 			obj->swd = adapter_driver->swd_ops;
+		} else if (transport_is_dapdirect_swd()) {
+			dap->ops = adapter_driver->dap_swd_ops;
+		} else if (transport_is_dapdirect_jtag()) {
+			dap->ops = adapter_driver->dap_jtag_ops;
 		} else
 			dap->ops = &jtag_dp_ops;
 

src/transport/transport.h

@@ -96,6 +96,8 @@ bool transports_are_declared(void);
 
 bool transport_is_jtag(void);
 bool transport_is_swd(void);
+bool transport_is_dapdirect_jtag(void);
+bool transport_is_dapdirect_swd(void);
 
 #if BUILD_HLADAPTER
 bool transport_is_hla(void);