ARM|Driver: Add DPI Driver for emulation

This driver provides support for Cadence JTAG BFM

The "jtag_dpi" driver implements a JTAG driver acting as a client for the
SystemVerilog Direct Programming Interface (DPI) for JTAG devices.
DPI allows OpenOCD to connect to the JTAG interface of a hardware model
written in SystemVerilog, for example, on an emulation model of
target hardware.

Tested on Ampere emulation with Altra and Altra Max models

Change-Id: Iaef8ba5cc1398ee2c888f39a606e8cb592484625
Signed-off-by: Kevin Burke <kevinb@os.amperecomputing.com>
Signed-off-by: Daniel Goehring <dgoehrin@os.amperecomputing.com>
Reviewed-on: http://openocd.zylin.com/5573
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

configure.ac

@@ -267,6 +267,10 @@ AC_ARG_ENABLE([jtag_vpi],
   AS_HELP_STRING([--enable-jtag_vpi], [Enable building support for JTAG VPI]),
   [build_jtag_vpi=$enableval], [build_jtag_vpi=no])
 
+AC_ARG_ENABLE([jtag_dpi],
+  AS_HELP_STRING([--enable-jtag_dpi], [Enable building support for JTAG DPI]),
+  [build_jtag_dpi=$enableval], [build_jtag_dpi=no])
+
 AC_ARG_ENABLE([amtjtagaccel],
   AS_HELP_STRING([--enable-amtjtagaccel], [Enable building the Amontec JTAG-Accelerator driver]),
   [build_amtjtagaccel=$enableval], [build_amtjtagaccel=no])
@@ -569,6 +573,13 @@ AS_IF([test "x$build_jtag_vpi" = "xyes"], [
   AC_DEFINE([BUILD_JTAG_VPI], [0], [0 if you don't want JTAG VPI.])
 ])
 
+AS_IF([test "x$build_jtag_dpi" = "xyes"], [
+  AC_DEFINE([BUILD_JTAG_DPI], [1], [1 if you want JTAG DPI.])
+], [
+  AC_DEFINE([BUILD_JTAG_DPI], [0], [0 if you don't want JTAG DPI.])
+])
+
+
 AS_IF([test "x$build_amtjtagaccel" = "xyes"], [
   AC_DEFINE([BUILD_AMTJTAGACCEL], [1], [1 if you want the Amontec JTAG-Accelerator driver.])
 ], [
@@ -746,6 +757,7 @@ AM_CONDITIONAL([BCM2835GPIO], [test "x$build_bcm2835gpio" = "xyes"])
 AM_CONDITIONAL([IMX_GPIO], [test "x$build_imx_gpio" = "xyes"])
 AM_CONDITIONAL([BITBANG], [test "x$build_bitbang" = "xyes"])
 AM_CONDITIONAL([JTAG_VPI], [test "x$build_jtag_vpi" = "xyes" -o "x$build_jtag_vpi" = "xyes"])
+AM_CONDITIONAL([JTAG_DPI], [test "x$build_jtag_dpi" = "xyes" -o "x$build_jtag_dpi" = "xyes"])
 AM_CONDITIONAL([USB_BLASTER_DRIVER], [test "x$enable_usb_blaster" != "xno" -o "x$enable_usb_blaster_2" != "xno"])
 AM_CONDITIONAL([AMTJTAGACCEL], [test "x$build_amtjtagaccel" = "xyes"])
 AM_CONDITIONAL([GW16012], [test "x$build_gw16012" = "xyes"])

doc/openocd.texi

@@ -615,6 +615,12 @@ produced, PDF schematics are easily found and it is easy to make.
 @* A JTAG driver acting as a client for the JTAG VPI server interface.
 @* Link: @url{http://github.com/fjullien/jtag_vpi}
 
+@item @b{jtag_dpi}
+@* A JTAG driver acting as a client for the SystemVerilog Direct Programming
+Interface (DPI) for JTAG devices. DPI allows OpenOCD to connect to the JTAG
+interface of a hardware model written in SystemVerilog, for example, on an
+emulation model of target hardware.
+
 @item @b{xlnx_pcie_xvc}
 @* A JTAG driver exposing Xilinx Virtual Cable over PCI Express to OpenOCD as JTAG/SWD interface.
 
@@ -3235,6 +3241,22 @@ This value is only used with the standard variant.
 @end deffn
 @end deffn
 
+
+@deffn {Interface Driver} {jtag_dpi}
+SystemVerilog Direct Programming Interface (DPI) compatible driver for
+JTAG devices in emulation. The driver acts as a client for the SystemVerilog
+DPI server interface.
+
+@deffn {Config Command} {jtag_dpi_set_port} port
+Specifies the TCP/IP port number of the SystemVerilog DPI server interface.
+@end deffn
+
+@deffn {Config Command} {jtag_dpi_set_address} address
+Specifies the TCP/IP address of the SystemVerilog DPI server interface.
+@end deffn
+@end deffn
+
+
 @section Transport Configuration
 @cindex Transport
 As noted earlier, depending on the version of OpenOCD you use,

src/jtag/drivers/Makefile.am

@@ -82,6 +82,9 @@ endif
 if JTAG_VPI
 DRIVERFILES += %D%/jtag_vpi.c
 endif
+if JTAG_DPI
+DRIVERFILES += %D%/jtag_dpi.c
+endif
 if USB_BLASTER_DRIVER
 %C%_libocdjtagdrivers_la_LIBADD += %D%/usb_blaster/libocdusbblaster.la
 include %D%/usb_blaster/Makefile.am

src/jtag/drivers/jtag_dpi.c

@@ -0,0 +1,407 @@
+/*
+ * JTAG to DPI driver
+ *
+ * Copyright (C) 2013 Franck Jullien, <elec4fun@gmail.com>
+ *
+ * Copyright (C) 2019-2020, Ampere Computing LLC
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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/>.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <jtag/interface.h>
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+
+#ifndef _WIN32
+#include <netinet/tcp.h>
+#endif
+
+#define SERVER_ADDRESS	"127.0.0.1"
+#define SERVER_PORT	5555
+
+static uint16_t server_port = SERVER_PORT;
+static char *server_address;
+
+static int sockfd;
+static struct sockaddr_in serv_addr;
+
+static uint8_t *last_ir_buf;
+static int last_ir_num_bits;
+
+static int write_sock(char *buf, size_t len)
+{
+	if (buf == NULL) {
+		LOG_ERROR("%s: NULL 'buf' argument, file %s, line %d",
+			__func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	if (write(sockfd, buf, len) != (ssize_t)len) {
+		LOG_ERROR("%s: %s, file %s, line %d", __func__,
+			strerror(errno), __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	return ERROR_OK;
+}
+
+static int read_sock(char *buf, size_t len)
+{
+	if (buf == NULL) {
+		LOG_ERROR("%s: NULL 'buf' argument, file %s, line %d",
+			__func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	if (read(sockfd, buf, len) != (ssize_t)len) {
+		LOG_ERROR("%s: %s, file %s, line %d", __func__,
+			strerror(errno), __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	return ERROR_OK;
+}
+
+/**
+ * jtag_dpi_reset - ask to reset the JTAG device
+ * @trst: 1 if TRST is to be asserted
+ * @srst: 1 if SRST is to be asserted
+ */
+static int jtag_dpi_reset(int trst, int srst)
+{
+	char *buf = "reset\n";
+	int ret = ERROR_OK;
+
+	LOG_DEBUG_IO("JTAG DRIVER DEBUG: reset trst: %i srst %i", trst, srst);
+
+	if (trst == 1) {
+		/* reset the JTAG TAP controller */
+		ret = write_sock(buf, strlen(buf));
+		if (ret != ERROR_OK) {
+			LOG_ERROR("write_sock() fail, file %s, line %d",
+				__FILE__, __LINE__);
+		}
+	}
+
+	if (srst == 1) {
+		/* System target reset not supported */
+		LOG_ERROR("DPI SRST not supported");
+		ret = ERROR_FAIL;
+	}
+
+	return ret;
+}
+
+/**
+ * jtag_dpi_scan - launches a DR-scan or IR-scan
+ * @cmd: the command to launch
+ *
+ * Launch a JTAG IR-scan or DR-scan
+ *
+ * Returns ERROR_OK if OK, ERROR_xxx if a read/write error occured.
+ */
+static int jtag_dpi_scan(struct scan_command *cmd)
+{
+	char buf[20];
+	uint8_t *data_buf;
+	int num_bits, bytes;
+	int ret = ERROR_OK;
+
+	num_bits = jtag_build_buffer(cmd, &data_buf);
+	if (data_buf == NULL) {
+		LOG_ERROR("jtag_build_buffer call failed, data_buf == NULL, "
+			"file %s, line %d", __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+
+	bytes = DIV_ROUND_UP(num_bits, 8);
+	if (cmd->ir_scan) {
+		free(last_ir_buf);
+		last_ir_buf = (uint8_t *)malloc(bytes * sizeof(uint8_t));
+		if (last_ir_buf == NULL) {
+			LOG_ERROR("%s: malloc fail, file %s, line %d",
+				__func__, __FILE__, __LINE__);
+			ret = ERROR_FAIL;
+			goto out;
+		}
+		memcpy(last_ir_buf, data_buf, bytes);
+		last_ir_num_bits = num_bits;
+	}
+	snprintf(buf, sizeof(buf), "%s %d\n", cmd->ir_scan ? "ib" : "db", num_bits);
+	ret = write_sock(buf, strlen(buf));
+	if (ret != ERROR_OK) {
+		LOG_ERROR("write_sock() fail, file %s, line %d",
+			__FILE__, __LINE__);
+		goto out;
+	}
+	ret = write_sock((char *)data_buf, bytes);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("write_sock() fail, file %s, line %d",
+			__FILE__, __LINE__);
+		goto out;
+	}
+	ret = read_sock((char *)data_buf, bytes);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("read_sock() fail, file %s, line %d",
+			__FILE__, __LINE__);
+		goto out;
+	}
+
+	ret = jtag_read_buffer(data_buf, cmd);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("jtag_read_buffer() fail, file %s, line %d",
+			__FILE__, __LINE__);
+		goto out;
+	}
+
+out:
+	free(data_buf);
+	return ret;
+}
+
+static int jtag_dpi_runtest(int cycles)
+{
+	char buf[20];
+	uint8_t *data_buf = last_ir_buf, *read_scan;
+	int num_bits = last_ir_num_bits, bytes;
+	int ret = ERROR_OK;
+
+	if (data_buf == NULL) {
+		LOG_ERROR("%s: NULL 'data_buf' argument, file %s, line %d",
+			__func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	if (num_bits <= 0) {
+		LOG_ERROR("%s: 'num_bits' invalid value, file %s, line %d",
+			__func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+
+	bytes = DIV_ROUND_UP(num_bits, 8);
+	read_scan = (uint8_t *)malloc(bytes * sizeof(uint8_t));
+	if (read_scan == NULL) {
+		LOG_ERROR("%s: malloc fail, file %s, line %d",
+			__func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+	snprintf(buf, sizeof(buf), "ib %d\n", num_bits);
+	while (cycles > 0) {
+		ret = write_sock(buf, strlen(buf));
+		if (ret != ERROR_OK) {
+			LOG_ERROR("write_sock() fail, file %s, line %d",
+				__FILE__, __LINE__);
+			goto out;
+		}
+		ret = write_sock((char *)data_buf, bytes);
+		if (ret != ERROR_OK) {
+			LOG_ERROR("write_sock() fail, file %s, line %d",
+				__FILE__, __LINE__);
+			goto out;
+		}
+		ret = read_sock((char *)read_scan, bytes);
+		if (ret != ERROR_OK) {
+			LOG_ERROR("read_sock() fail, file %s, line %d",
+				__FILE__, __LINE__);
+			goto out;
+		}
+
+		cycles -= num_bits + 6;
+	}
+
+out:
+	free(read_scan);
+	return ret;
+}
+
+static int jtag_dpi_stableclocks(int cycles)
+{
+	return jtag_dpi_runtest(cycles);
+}
+
+static int jtag_dpi_execute_queue(void)
+{
+	struct jtag_command *cmd;
+	int ret = ERROR_OK;
+
+	for (cmd = jtag_command_queue; ret == ERROR_OK && cmd != NULL;
+	     cmd = cmd->next) {
+		switch (cmd->type) {
+		case JTAG_RUNTEST:
+			ret = jtag_dpi_runtest(cmd->cmd.runtest->num_cycles);
+			break;
+		case JTAG_STABLECLOCKS:
+			ret = jtag_dpi_stableclocks(cmd->cmd.stableclocks->num_cycles);
+			break;
+		case JTAG_TLR_RESET:
+			/* Enter Test-Logic-Reset state by asserting TRST */
+			if (cmd->cmd.statemove->end_state == TAP_RESET)
+				jtag_dpi_reset(1, 0);
+			break;
+		case JTAG_PATHMOVE:
+			/* unsupported */
+			break;
+		case JTAG_TMS:
+			/* unsupported */
+			break;
+		case JTAG_SLEEP:
+			jtag_sleep(cmd->cmd.sleep->us);
+			break;
+		case JTAG_SCAN:
+			ret = jtag_dpi_scan(cmd->cmd.scan);
+			break;
+		default:
+			LOG_ERROR("BUG: unknown JTAG command type 0x%X",
+				  cmd->type);
+			ret = ERROR_FAIL;
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static int jtag_dpi_init(void)
+{
+	sockfd = socket(AF_INET, SOCK_STREAM, 0);
+	if (sockfd < 0) {
+		LOG_ERROR("socket: %s, function %s, file %s, line %d",
+			strerror(errno), __func__, __FILE__, __LINE__);
+		return ERROR_FAIL;
+	}
+
+	memset(&serv_addr, 0, sizeof(serv_addr));
+
+	serv_addr.sin_family = AF_INET;
+	serv_addr.sin_port = htons(server_port);
+
+	if (server_address == NULL) {
+		server_address = strdup(SERVER_ADDRESS);
+		if (server_address == NULL) {
+			LOG_ERROR("%s: strdup fail, file %s, line %d",
+				__func__, __FILE__, __LINE__);
+			return ERROR_FAIL;
+		}
+	}
+
+	serv_addr.sin_addr.s_addr = inet_addr(server_address);
+
+	if (serv_addr.sin_addr.s_addr == INADDR_NONE) {
+		LOG_ERROR("inet_addr error occured");
+		return ERROR_FAIL;
+	}
+
+	if (connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0) {
+		close(sockfd);
+		LOG_ERROR("Can't connect to %s : %" PRIu16, server_address, server_port);
+		return ERROR_FAIL;
+	}
+	if (serv_addr.sin_addr.s_addr == htonl(INADDR_LOOPBACK)) {
+		/* This increases performance dramatically for local
+		* connections, which is the most likely arrangement
+		* for a DPI connection. */
+		int flag = 1;
+		setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(int));
+	}
+
+	LOG_INFO("Connection to %s : %" PRIu16 " succeed", server_address, server_port);
+
+	return ERROR_OK;
+}
+
+static int jtag_dpi_quit(void)
+{
+	free(server_address);
+	server_address = NULL;
+
+	return close(sockfd);
+}
+
+COMMAND_HANDLER(jtag_dpi_set_port)
+{
+	if (CMD_ARGC > 1)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+	else if (CMD_ARGC == 0)
+		LOG_INFO("Using server port %" PRIu16, server_port);
+	else {
+		COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], server_port);
+		LOG_INFO("Set server port to %" PRIu16, server_port);
+	}
+
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(jtag_dpi_set_address)
+{
+	if (CMD_ARGC > 1)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+	else if (CMD_ARGC == 0) {
+		if (server_address == NULL) {
+			server_address = strdup(SERVER_ADDRESS);
+			if (server_address == NULL) {
+				LOG_ERROR("%s: strdup fail, file %s, line %d",
+					__func__, __FILE__, __LINE__);
+				return ERROR_FAIL;
+			}
+		}
+		LOG_INFO("Using server address %s", server_address);
+	} else {
+		free(server_address);
+		server_address = strdup(CMD_ARGV[0]);
+		if (server_address == NULL) {
+			LOG_ERROR("%s: strdup fail, file %s, line %d",
+				__func__, __FILE__, __LINE__);
+			return ERROR_FAIL;
+		}
+		LOG_INFO("Set server address to %s", server_address);
+	}
+
+	return ERROR_OK;
+}
+
+static const struct command_registration jtag_dpi_command_handlers[] = {
+	{
+		.name = "jtag_dpi_set_port",
+		.handler = &jtag_dpi_set_port,
+		.mode = COMMAND_CONFIG,
+		.help = "set the port of the DPI server",
+		.usage = "[port]",
+	},
+	{
+		.name = "jtag_dpi_set_address",
+		.handler = &jtag_dpi_set_address,
+		.mode = COMMAND_CONFIG,
+		.help = "set the address of the DPI server",
+		.usage = "[address]",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static struct jtag_interface jtag_dpi_interface = {
+	.supported = DEBUG_CAP_TMS_SEQ,
+	.execute_queue = jtag_dpi_execute_queue,
+};
+
+struct adapter_driver jtag_dpi_adapter_driver = {
+	.name = "jtag_dpi",
+	.transports = jtag_only,
+	.commands = jtag_dpi_command_handlers,
+	.init = jtag_dpi_init,
+	.quit = jtag_dpi_quit,
+	.reset = jtag_dpi_reset,
+	.jtag_ops = &jtag_dpi_interface,
+};

src/jtag/interfaces.c

@@ -12,6 +12,8 @@
  *   Copyright (C) 2009 Zachary T Welch                                    *
  *   zw@superlucidity.net                                                  *
  *                                                                         *
+ *   Copyright (C) 2020, Ampere Computing LLC                              *
+ *                                                                         *
  *   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     *
@@ -60,6 +62,9 @@ extern struct adapter_driver usb_blaster_adapter_driver;
 #if BUILD_JTAG_VPI == 1
 extern struct adapter_driver jtag_vpi_adapter_driver;
 #endif
+#if BUILD_JTAG_DPI == 1
+extern struct adapter_driver jtag_dpi_adapter_driver;
+#endif
 #if BUILD_FT232R == 1
 extern struct adapter_driver ft232r_adapter_driver;
 #endif
@@ -177,6 +182,9 @@ struct adapter_driver *adapter_drivers[] = {
 #if BUILD_JTAG_VPI == 1
 		&jtag_vpi_adapter_driver,
 #endif
+#if BUILD_JTAG_DPI == 1
+		&jtag_dpi_adapter_driver,
+#endif
 #if BUILD_FT232R == 1
 		&ft232r_adapter_driver,
 #endif

tcl/interface/jtag_dpi.cfg

@@ -0,0 +1,38 @@
+#
+# Provide support for the Cadence JTAG BFM
+#
+# Copyright (c) 2020, Ampere Computing LLC
+#
+# 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;
+#
+#
+
+adapter driver jtag_dpi
+
+# Set the DPI JTAG server port
+if { [info exists DPI_PORT] } {
+   set _DPI_PORT $DPI_PORT
+} else {
+   set _DPI_PORT 5555
+}
+
+# Set the DPI JTAG server address
+if { [info exists DPI_ADDRESS] } {
+   set _DPI_ADDRESS $DPI_ADDRESS
+} else {
+   set _DPI_ADDRESS "127.0.0.1"
+}
+
+jtag_dpi_set_port $_DPI_PORT
+jtag_dpi_set_address $_DPI_ADDRESS