target/aarch64: a64 disassembler

Add A64 (AArch64) Disassembler using Capstone framework.

Change-Id: Ia92b57001843b11a818af940a468b131e42a03fd
Signed-off-by: Mete Balci <metebalci@gmail.com>
[Antonio Borneo: Rebased on current HEAD]
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5004
Tested-by: jenkins

src/target/Makefile.am

@@ -89,6 +89,7 @@ ARMV8_SRC = \
 	%D%/armv8_dpm.c \
 	%D%/armv8_opcodes.c \
 	%D%/aarch64.c \
+	%D%/a64_disassembler.c \
 	%D%/armv8.c \
 	%D%/armv8_cache.c
 
@@ -176,6 +177,7 @@ ARC_SRC = \
 	%D%/armv7a_cache_l2x.h \
 	%D%/armv7a_mmu.h \
 	%D%/arm_disassembler.h \
+	%D%/a64_disassembler.h \
 	%D%/arm_opcodes.h \
 	%D%/arm_simulator.h \
 	%D%/arm_semihosting.h \

src/target/a64_disassembler.c

@@ -0,0 +1,145 @@
+/***************************************************************************
+ *   Copyright (C) 2019 by Mete Balci                                      *
+ *   metebalci@gmail.com                                                   *
+ *                                                                         *
+ *   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 <helper/log.h>
+#include "target.h"
+#include "a64_disassembler.h"
+
+#if HAVE_CAPSTONE
+
+#include <capstone/capstone.h>
+
+static void print_opcode(struct command_invocation *cmd, const cs_insn *insn)
+{
+	uint32_t opcode = 0;
+
+	memcpy(&opcode, insn->bytes, insn->size);
+
+	if (insn->size == 4) {
+
+		uint16_t opcode_high = opcode >> 16;
+
+		opcode = opcode & 0xffff;
+
+		command_print(cmd,
+				"0x%08" PRIx64"  %04x %04x\t%s\t%s",
+				insn->address,
+				opcode,
+				opcode_high,
+				insn->mnemonic,
+				insn->op_str);
+
+	} else {
+
+		command_print(
+				cmd,
+				"0x%08" PRIx64"  %04x\t%s\t%s",
+				insn->address,
+				opcode,
+				insn->mnemonic,
+				insn->op_str);
+
+	}
+}
+
+int a64_disassemble(struct command_invocation *cmd, struct target *target, target_addr_t address, size_t count)
+{
+	int ret;
+	int csret;
+	csh handle;
+
+	csret = cs_open(CS_ARCH_ARM64, CS_MODE_LITTLE_ENDIAN, &handle);
+
+	if (csret != CS_ERR_OK) {
+
+		LOG_ERROR("cs_open() failed: %s", cs_strerror(csret));
+		return ERROR_FAIL;
+
+	}
+
+	csret = cs_option(handle, CS_OPT_SKIPDATA, CS_OPT_ON);
+
+	if (csret != CS_ERR_OK) {
+
+		LOG_ERROR("cs_option() failed: %s", cs_strerror(csret));
+		cs_close(&handle);
+		return ERROR_FAIL;
+
+	}
+
+	cs_insn *insn = cs_malloc(handle);
+
+	if (csret != CS_ERR_OK) {
+
+		LOG_ERROR("cs_malloc() failed: %s", cs_strerror(csret));
+		cs_close(&handle);
+		return ERROR_FAIL;
+
+	}
+
+	while (count > 0) {
+
+		uint8_t buffer[4];
+
+		ret = target_read_buffer(target, address, sizeof(buffer), buffer);
+
+		if (ret != ERROR_OK) {
+			cs_free(insn, 1);
+			cs_close(&handle);
+			return ret;
+		}
+
+		size_t size = sizeof(buffer);
+		const uint8_t *tmp = buffer;
+
+		ret = cs_disasm_iter(handle, &tmp, &size, &address, insn);
+
+		if (!ret) {
+
+			LOG_ERROR("cs_disasm_iter() failed: %s", cs_strerror(cs_errno(handle)));
+			cs_free(insn, 1);
+			cs_close(&handle);
+			return ERROR_FAIL;
+
+		}
+
+		print_opcode(cmd, insn);
+		count--;
+
+	}
+
+	cs_free(insn, 1);
+	cs_close(&handle);
+
+	return ERROR_OK;
+}
+
+#else
+
+int a64_disassemble(struct command_invocation *cmd, struct target *target, target_addr_t address, size_t count)
+{
+	command_print(cmd, "capstone disassembly framework required");
+
+	return ERROR_FAIL;
+}
+
+#endif

src/target/a64_disassembler.h

@@ -0,0 +1,30 @@
+/***************************************************************************
+ *   Copyright (C) 2019 by Mete Balci                                      *
+ *   metebalci@gmail.com                                                   *
+ *                                                                         *
+ *   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/>. *
+ ***************************************************************************/
+
+#ifndef OPENOCD_TARGET_AARCH64_DISASSEMBLER_H
+#define OPENOCD_TARGET_AARCH64_DISASSEMBLER_H
+
+#include "target.h"
+
+int a64_disassemble(
+		struct command_invocation *cmd,
+		struct target *target,
+		target_addr_t address,
+		size_t count);
+
+#endif /* OPENOCD_TARGET_AARCH64_DISASSEMBLER_H */

src/target/aarch64.c

@@ -23,6 +23,7 @@
 
 #include "breakpoints.h"
 #include "aarch64.h"
+#include "a64_disassembler.h"
 #include "register.h"
 #include "target_request.h"
 #include "target_type.h"
@@ -2566,7 +2567,6 @@ COMMAND_HANDLER(aarch64_handle_cache_info_command)
 			&armv8->armv8_mmu.armv8_cache);
 }
 
-
 COMMAND_HANDLER(aarch64_handle_dbginit_command)
 {
 	struct target *target = get_current_target(CMD_CTX);
@@ -2578,6 +2578,39 @@ COMMAND_HANDLER(aarch64_handle_dbginit_command)
 	return aarch64_init_debug_access(target);
 }
 
+COMMAND_HANDLER(aarch64_handle_disassemble_command)
+{
+	struct target *target = get_current_target(CMD_CTX);
+
+	if (target == NULL) {
+		LOG_ERROR("No target selected");
+		return ERROR_FAIL;
+	}
+
+	struct aarch64_common *aarch64 = target_to_aarch64(target);
+
+	if (aarch64->common_magic != AARCH64_COMMON_MAGIC) {
+		command_print(CMD, "current target isn't an AArch64");
+		return ERROR_FAIL;
+	}
+
+	int count = 1;
+	target_addr_t address;
+
+	switch (CMD_ARGC) {
+		case 2:
+			COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], count);
+		/* FALL THROUGH */
+		case 1:
+			COMMAND_PARSE_ADDRESS(CMD_ARGV[0], address);
+			break;
+		default:
+			return ERROR_COMMAND_SYNTAX_ERROR;
+	}
+
+	return a64_disassemble(CMD, target, address, count);
+}
+
 COMMAND_HANDLER(aarch64_mask_interrupts_command)
 {
 	struct target *target = get_current_target(CMD_CTX);
@@ -2758,6 +2791,13 @@ static const struct command_registration aarch64_exec_command_handlers[] = {
 		.help = "Initialize core debug",
 		.usage = "",
 	},
+	{
+		.name = "disassemble",
+		.handler = aarch64_handle_disassemble_command,
+		.mode = COMMAND_EXEC,
+		.help = "Disassemble instructions",
+		.usage = "address [count]",
+	},
 	{
 		.name = "maskisr",
 		.handler = aarch64_mask_interrupts_command,