- the 'help' command now takes an optional argument to display help only on a certain command (thanks to Andrew Dyer for this enhancement)

- OpenOCD now includes the ability to diassemble instructions on its own (only ARM for now, Thumb might follow). 
The command is "armv4_5 disassemble <address> <count> ['thumb']" (thumb is currently unsupported).
I've compared the produced disassembly against GDB/GNU Objdump output, and it seems to be correct, but there may still be some bugs left.


git-svn-id: svn://svn.berlios.de/openocd/trunk@68 b42882b7-edfa-0310-969c-e2dbd0fdcd60

5 files changed, 1403 insertions, 2 deletions

diff --git a/src/helper/command.c b/src/helper/command.c
index 00d4b356..9fc78422 100644
--- a/src/helper/command.c
+++ b/src/helper/command.c
@@ -443,6 +443,15 @@ int command_print_help(command_context_t* context, char* name, char** args, int
 
 	for (c = context->commands; c; c = c->next)
 	{
+		if (argc == 1)
+		{
+			 if (strncasecmp(c->name, args[0], c->unique_len))
+				 continue;
+
+			 if (strncasecmp(c->name, args[0], strlen(args[0])))
+				 continue;
+		} 
+
 		command_print_help_line(context, c, 0);
 	}
 	
diff --git a/src/target/Makefile.am b/src/target/Makefile.am
index 7e26762b..2192469c 100644
--- a/src/target/Makefile.am
+++ b/src/target/Makefile.am
@@ -2,6 +2,7 @@ INCLUDES = -I$(top_srcdir)/src/gdb -I$(top_srcdir)/src/helper 	-I$(top_srcdir)/s
 METASOURCES = AUTO
 noinst_LIBRARIES = libtarget.a
 libtarget_a_SOURCES = target.c register.c breakpoints.c armv4_5.c embeddedice.c etm.c arm7tdmi.c arm9tdmi.c \
-	arm_jtag.c arm7_9_common.c algorithm.c arm920t.c arm720t.c armv4_5_mmu.c armv4_5_cache.c
+	arm_jtag.c arm7_9_common.c algorithm.c arm920t.c arm720t.c armv4_5_mmu.c armv4_5_cache.c arm_disassembler.c
 noinst_HEADERS = target.h register.h armv4_5.h embeddedice.h etm.h arm7tdmi.h arm9tdmi.h \
-		arm_jtag.h arm7_9_common.h arm920t.h arm720t.h armv4_5_mmu.h armv4_5_cache.h breakpoints.h algorithm.h
+		arm_jtag.h arm7_9_common.h arm920t.h arm720t.h armv4_5_mmu.h armv4_5_cache.h breakpoints.h algorithm.h \
+		arm_disassembler.h
diff --git a/src/target/arm_disassembler.c b/src/target/arm_disassembler.c
new file mode 100644
index 00000000..6e76cf39
--- /dev/null
+++ b/src/target/arm_disassembler.c
@@ -0,0 +1,1209 @@
+/***************************************************************************
+ *   Copyright (C) 2006 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   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, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#include "arm_disassembler.h"
+
+#include "log.h"
+
+#include <strings.h>
+
+/* textual represenation of the condition field */
+/* ALways (default) is ommitted (empty string) */
+char *arm_condition_strings[] =
+{
+	"EQ", "NE", "CS", "CC", "MI", "PL", "VS", "VC", "HI", "LS", "GE", "LT", "GT", "LE", "", "NV"
+};
+
+/* make up for C's missing ROR */
+u32 ror(u32 value, int places) 
+{ 
+	return (value >> places) | (value << (32 - places)); 
+}
+
+int evaluate_pld(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	/* PLD */
+	if ((opcode & 0x0d70f0000) == 0x0550f000)
+	{
+		instruction->type = ARM_PLD;
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tPLD ...TODO...", address, opcode);
+		
+		return ERROR_OK;
+	}
+	else
+	{
+		instruction->type = ARM_UNDEFINED_INSTRUCTION;
+		return ERROR_OK;
+	}
+	
+	ERROR("should never reach this point");
+	return -1;
+}
+
+int evaluate_swi(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	instruction->type = ARM_SWI;
+	
+	snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSWI 0x%6.6x", address, opcode, (opcode & 0xffffff));
+	
+	return ERROR_OK;
+}
+
+int evaluate_blx_imm(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	int offset;
+	u32 immediate;
+	
+	instruction->type = ARM_BLX;
+	immediate = opcode & 0x00ffffff;
+	
+	/* sign extend 24-bit immediate */
+	if (immediate & 0x00800000)
+		offset = 0xff000000 | immediate;
+	else
+		offset = immediate;
+	
+	/* shift two bits left */
+	offset <<= 2;
+	
+	/* odd/event halfword */
+	if (opcode & 0x01000000)
+		offset |= 0x2;
+	
+	instruction->target_address = address + 8 + offset;
+	
+	snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tBLX 0x%8.8x", address, opcode, instruction->target_address);
+	
+	return ERROR_OK;
+}
+
+int evaluate_b_bl(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 L;
+	u32 immediate;
+	int offset;
+	
+	immediate = opcode & 0x00ffffff;
+	L = (opcode & 0x01000000) >> 24;
+	
+	/* sign extend 24-bit immediate */
+	if (immediate & 0x00800000)
+		offset = 0xff000000 | immediate;
+	else
+		offset = immediate;
+	
+	/* shift two bits left */
+	offset <<= 2;
+	
+	instruction->target_address = address + 8 + offset;
+
+	if (L)
+		instruction->type = ARM_BL;
+	else
+		instruction->type = ARM_B;
+	
+	snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tB%s%s 0x%8.8x", address, opcode,
+			 (L) ? "L" : "", COND(opcode), instruction->target_address);
+	
+	return ERROR_OK;
+}
+
+/* Coprocessor load/store and double register transfers */
+/* both normal and extended instruction space (condition field b1111) */
+int evaluate_ldc_stc_mcrr_mrrc(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 cp_num = (opcode & 0xf00) >> 8;
+	
+	/* MCRR or MRRC */
+	if (((opcode & 0x0ff00000) == 0x0c400000) || ((opcode & 0x0ff00000) == 0x0c400000))
+	{
+		u8 cp_opcode, Rd, Rn, CRm;
+		char *mnemonic;
+		
+		cp_opcode = (opcode & 0xf0) >> 4;
+		Rd = (opcode & 0xf000) >> 12;
+		Rn = (opcode & 0xf0000) >> 16;
+		CRm = (opcode & 0xf);
+		
+		/* MCRR */
+		if ((opcode & 0x0ff00000) == 0x0c400000)
+		{
+			instruction->type = ARM_MCRR;
+			mnemonic = "MCRR";
+		}
+		
+		/* MRRC */
+		if ((opcode & 0x0ff00000) == 0x0c500000)
+		{
+			instruction->type = ARM_MRRC;
+			mnemonic = "MRRC";
+		}
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s p%i, %x, r%i, r%i, c%i",
+				 address, opcode, mnemonic, COND(opcode), cp_num, cp_opcode, Rd, Rn, CRm);
+	}
+	else /* LDC or STC */
+	{
+		u8 CRd, Rn, offset;
+		u8 U, N;
+		char *mnemonic;
+		char addressing_mode[32];
+		
+		CRd = (opcode & 0xf000) >> 12;
+		Rn = (opcode & 0xf0000) >> 16;
+		offset = (opcode & 0xff);
+		
+		/* load/store */
+		if (opcode & 0x00100000)
+		{
+			instruction->type = ARM_LDC;
+			mnemonic = "LDC";
+		}
+		else
+		{
+			instruction->type = ARM_STC;
+			mnemonic = "STC";
+		}
+		
+		U = (opcode & 0x00800000) >> 23;
+		N = (opcode & 0x00400000) >> 22;
+		
+		/* addressing modes */
+		if ((opcode & 0x01200000) == 0x01000000) /* immediate offset */
+			snprintf(addressing_mode, 32, "[r%i, #%s0x%2.2x*4]", Rn, (U) ? "" : "-", offset);
+		else if ((opcode & 0x01200000) == 0x01200000) /* immediate pre-indexed */
+			snprintf(addressing_mode, 32, "[r%i, #%s0x%2.2x*4]!", Rn, (U) ? "" : "-", offset);
+		else if ((opcode & 0x01200000) == 0x00200000) /* immediate post-indexed */
+			snprintf(addressing_mode, 32, "[r%i], #%s0x%2.2x*4", Rn, (U) ? "" : "-", offset);
+		else if ((opcode & 0x01200000) == 0x00000000) /* unindexed */
+			snprintf(addressing_mode, 32, "[r%i], #0x%2.2x", Rn, offset);
+
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s p%i, c%i, %s",
+				 address, opcode, mnemonic, ((opcode & 0xf0000000) == 0xf0000000) ? COND(opcode) : "2",
+				 (N) ? "L" : "",
+				 cp_num, CRd, addressing_mode);
+	}
+	
+	return ERROR_OK;
+}
+
+/* Coprocessor data processing instructions */
+/* Coprocessor register transfer instructions */
+/* both normal and extended instruction space (condition field b1111) */
+int evaluate_cdp_mcr_mrc(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	char* cond;
+	char* mnemonic;
+	u8 cp_num, opcode_1, CRd_Rd, CRn, CRm, opcode_2;
+	
+	cond = ((opcode & 0xf0000000) == 0xf0000000) ? "2" : COND(opcode);
+	cp_num = (opcode & 0xf00) >> 8;
+	CRd_Rd = (opcode & 0xf000) >> 12;
+	CRn = (opcode & 0xf0000) >> 16;
+	CRm = (opcode & 0xf);
+	opcode_2 = (opcode & 0xe0) >> 5;
+	
+	/* CDP or MRC/MCR */
+	if (opcode & 0x00000010) /* bit 4 set -> MRC/MCR */
+	{
+		if (opcode & 0x00100000) /* bit 20 set -> MRC */
+		{
+			instruction->type = ARM_MRC;
+			mnemonic = "MRC";
+		}
+		else /* bit 20 not set -> MCR */
+		{
+			instruction->type = ARM_MCR;
+			mnemonic = "MCR";
+		}
+		
+		opcode_1 = (opcode & 0x00e00000) >> 21;
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s p%i, 0x%2.2x, r%i, c%i, c%i, 0x%2.2x",
+				 address, opcode, mnemonic, cond,
+				 cp_num, opcode_1, CRd_Rd, CRn, CRm, opcode_2);
+	}
+	else /* bit 4 not set -> CDP */
+	{
+		instruction->type = ARM_CDP;
+		mnemonic = "CDP";
+		
+		opcode_1 = (opcode & 0x00f00000) >> 20;
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s p%i, 0x%2.2x, c%i, c%i, c%i, 0x%2.2x",
+				 address, opcode, mnemonic, cond,
+				 cp_num, opcode_1, CRd_Rd, CRn, CRm, opcode_2);
+	}
+	
+	return ERROR_OK;
+}
+
+/* Load/store instructions */
+int evaluate_load_store(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 I, P, U, B, W, L;
+	u8 Rn, Rd;
+	char *operation; /* "LDR" or "STR" */
+	char *suffix; /* "", "B", "T", "BT" */
+	char offset[32];
+	
+	/* examine flags */
+	I = (opcode & 0x02000000) >> 25;
+	P = (opcode & 0x01000000) >> 24;
+	U = (opcode & 0x00800000) >> 23;
+	B = (opcode & 0x00400000) >> 22;
+	W = (opcode & 0x00200000) >> 21;
+	L = (opcode & 0x00100000) >> 20;
+	
+	/* target register */
+	Rd = (opcode & 0xf000) >> 12;
+	
+	/* base register */
+	Rn = (opcode & 0xf0000) >> 16;
+	
+	/* determine operation */
+	if (L)
+		operation = "LDR";
+	else
+		operation = "STR";
+	
+	/* determine instruction type and suffix */
+	if (B)
+	{
+		if ((P == 0) && (W == 1))
+		{
+			if (L)
+				instruction->type = ARM_LDRBT;
+			else
+				instruction->type = ARM_STRBT;
+			suffix = "BT";
+		}
+		else
+		{
+			if (L)
+				instruction->type = ARM_LDRB;
+			else
+				instruction->type = ARM_STRB;
+			suffix = "B";
+		}
+	}
+	else
+	{
+		if ((P == 0) && (W == 1))
+		{
+			if (L)
+				instruction->type = ARM_LDRT;
+			else
+				instruction->type = ARM_STRT;
+			suffix = "T";
+		}
+		else
+		{
+			if (L)
+				instruction->type = ARM_LDR;
+			else
+				instruction->type = ARM_STR;
+			suffix = "";
+		}
+	}
+	
+	if (!I) /* #+-<offset_12> */
+	{
+		u32 offset_12 = (opcode & 0xfff);
+		snprintf(offset, 32, "#%s0x%x", (U) ? "" : "-", offset_12);
+	}
+	else /* either +-<Rm> or +-<Rm>, <shift>, #<shift_imm> */
+	{
+		u8 shift_imm, shift;
+		u8 Rm;
+		
+		shift_imm = (opcode & 0xf80) >> 7;
+		shift = (opcode & 0x60) >> 5;
+		Rm = (opcode & 0xf);
+		
+		if ((shift_imm == 0x0) && (shift == 0x0)) /* +-<Rm> */
+		{
+			snprintf(offset, 32, "%sr%i", (U) ? "" : "-", Rm);
+		}
+		else /* +-<Rm>, <Shift>, #<shift_imm> */
+		{
+			if (shift == 0x0) /* LSL */
+			{
+				snprintf(offset, 32, "%sr%i, LSL #0x%x", (U) ? "" : "-", Rm, shift_imm);
+			}
+			else if (shift == 0x1) /* LSR */
+			{
+				snprintf(offset, 32, "%sr%i, LSR #0x%x", (U) ? "" : "-", Rm, shift_imm);
+			}
+			else if (shift == 0x2) /* ASR */
+			{
+				snprintf(offset, 32, "%sr%i, ASR #0x%x", (U) ? "" : "-", Rm, shift_imm);
+			}
+			else if (shift == 0x3) /* ROR or RRX */
+			{
+				if (shift_imm == 0x0) /* RRX */
+					snprintf(offset, 32, "%sr%i, RRX", (U) ? "" : "-", Rm);
+				else
+					snprintf(offset, 32, "%sr%i, ROR #0x%x", (U) ? "" : "-", Rm, shift_imm);
+			}
+		}
+	}
+	
+	if (P == 1)
+	{
+		if (W == 0) /* offset */
+		{
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i, %s]",
+					 address, opcode, operation, COND(opcode), suffix,
+					 Rd, Rn, offset);
+		}
+		else /* pre-indexed */
+		{
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i, %s]!",
+					 address, opcode, operation, COND(opcode), suffix,
+					 Rd, Rn, offset);
+		}
+	}
+	else /* post-indexed */
+	{
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i], %s",
+				 address, opcode, operation, COND(opcode), suffix,
+				 Rd, Rn, offset);
+	}
+	
+	return ERROR_OK;
+}
+
+/* Miscellaneous load/store instructions */
+int evaluate_misc_load_store(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 P, U, I, W, L, S, H;
+	u8 Rn, Rd;
+	char *operation; /* "LDR" or "STR" */
+	char *suffix; /* "H", "SB", "SH", "D" */
+	char offset[32];
+	
+	/* examine flags */
+	P = (opcode & 0x01000000) >> 24;
+	U = (opcode & 0x00800000) >> 23;
+	I = (opcode & 0x00400000) >> 22;
+	W = (opcode & 0x00200000) >> 21;
+	L = (opcode & 0x00100000) >> 20;
+	S = (opcode & 0x00000040) >> 6;
+	H = (opcode & 0x00000020) >> 5;
+	
+	/* target register */
+	Rd = (opcode & 0xf000) >> 12;
+	
+	/* base register */
+	Rn = (opcode & 0xf0000) >> 16;
+	
+	/* determine instruction type and suffix */
+	if (S) /* signed */
+	{
+		if (L) /* load */
+		{
+			if (H)
+			{
+				operation = "LDR";
+				instruction->type = ARM_LDRSH;
+				suffix = "SH";
+			}
+			else
+			{
+				operation = "LDR";
+				instruction->type = ARM_LDRSB;
+				suffix = "SB";
+			}
+		}
+		else /* there are no signed stores, so this is used to encode double-register load/stores */
+		{
+			suffix = "D";
+			if (H)
+			{
+				operation = "STR";
+				instruction->type = ARM_STRD;
+			}
+			else
+			{
+				operation = "LDR";
+				instruction->type = ARM_LDRD;
+			}
+		}
+	}
+	else /* unsigned */
+	{
+		suffix = "H";
+		if (L) /* load */
+		{
+			operation = "LDR";
+			instruction->type = ARM_LDRH;
+		}
+		else /* store */
+		{
+			operation = "STR";
+			instruction->type = ARM_STRH;
+		}
+	}
+	
+	if (I) /* Immediate offset/index (#+-<offset_8>)*/
+	{
+		u32 offset_8 = ((opcode & 0xf00) >> 4) | (opcode & 0xf);
+		snprintf(offset, 32, "#%s0x%x", (U) ? "" : "-", offset_8);
+	}
+	else /* Register offset/index (+-<Rm>) */
+	{
+		u8 Rm;
+		Rm = (opcode & 0xf);
+		snprintf(offset, 32, "%sr%i", (U) ? "" : "-", Rm);
+	}
+	
+	if (P == 1)
+	{
+		if (W == 0) /* offset */
+		{
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i, %s]",
+					 address, opcode, operation, COND(opcode), suffix,
+					 Rd, Rn, offset);
+		}
+		else /* pre-indexed */
+		{
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i, %s]!",
+					 address, opcode, operation, COND(opcode), suffix,
+					 Rd, Rn, offset);
+		}
+	}
+	else /* post-indexed */
+	{
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, [r%i], %s",
+				 address, opcode, operation, COND(opcode), suffix,
+				 Rd, Rn, offset);
+	}
+	
+	return ERROR_OK;
+}
+
+/* Load/store multiples instructions */
+int evaluate_ldm_stm(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 P, U, S, W, L, Rn;
+	u32 register_list;
+	char *addressing_mode;
+	char *mnemonic;
+	char reg_list[69];
+	char *reg_list_p;
+	int i;
+	int first_reg = 1;
+	
+	P = (opcode & 0x01000000) >> 24;
+	U = (opcode & 0x00800000) >> 23;
+	S = (opcode & 0x00400000) >> 22;
+	W = (opcode & 0x00200000) >> 21;
+	L = (opcode & 0x00100000) >> 20;
+	register_list = (opcode & 0xffff);
+	Rn = (opcode & 0xf0000) >> 16;
+	
+	if (L)
+	{
+		instruction->type = ARM_LDM;
+		mnemonic = "LDM";
+	}
+	else
+	{
+		instruction->type = ARM_STM;
+		mnemonic = "STM";
+	}
+	
+	if (P)
+	{
+		if (U)
+			addressing_mode = "IB";
+		else
+			addressing_mode = "DB";
+	}
+	else
+	{
+		if (U)
+			addressing_mode = "IA";
+		else
+			addressing_mode = "DA";
+	}
+	
+	reg_list_p = reg_list;
+	for (i = 0; i <= 15; i++)
+	{
+		if ((register_list >> i) & 1)
+		{
+			if (first_reg)
+			{
+				first_reg = 0;
+				reg_list_p += snprintf(reg_list_p, (reg_list + 69 - reg_list_p), "r%i", i);
+			}
+			else
+			{
+				reg_list_p += snprintf(reg_list_p, (reg_list + 69 - reg_list_p), ", r%i", i);
+			}
+		}
+	}
+	
+	snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i%s, {%s}%s",
+			 address, opcode, mnemonic, COND(opcode), addressing_mode,
+			 Rn, (W) ? "!" : "", reg_list, (S) ? "^" : "");
+	
+	return ERROR_OK;
+}
+
+/* Multiplies, extra load/stores */
+int evaluate_mul_and_extra_ld_st(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	/* Multiply (accumulate) (long) and Swap/swap byte */
+	if ((opcode & 0x000000f0) == 0x00000090)
+	{
+		/* Multiply (accumulate) */
+		if ((opcode & 0x0f800000) == 0x00000000)
+		{
+			u8 Rm, Rs, Rn, Rd, S;
+			Rm = opcode & 0xf;
+			Rs = (opcode & 0xf00) >> 8;
+			Rn = (opcode & 0xf000) >> 12;
+			Rd = (opcode & 0xf0000) >> 16;
+			S = (opcode & 0x00100000) >> 20;
+			
+			/* examine A bit (accumulate) */
+			if (opcode & 0x00200000)
+			{
+				instruction->type = ARM_MLA;
+				snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tMLA%s%s r%i, r%i, r%i, r%i",
+						address, opcode, COND(opcode), (S) ? "S" : "", Rd, Rm, Rs, Rn);
+			}
+			else
+			{
+				instruction->type = ARM_MUL;
+				snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tMUL%s%s r%i, r%i, r%i",
+						 address, opcode, COND(opcode), (S) ? "S" : "", Rd, Rm, Rs);
+			}
+			
+			return ERROR_OK;
+		}
+		
+		/* Multiply (accumulate) long */
+		if ((opcode & 0x0f800000) == 0x00800000)
+		{
+			char* mnemonic;
+			u8 Rm, Rs, RdHi, RdLow, S;
+			Rm = opcode & 0xf;
+			Rs = (opcode & 0xf00) >> 8;
+			RdHi = (opcode & 0xf000) >> 12;
+			RdLow = (opcode & 0xf0000) >> 16;
+			S = (opcode & 0x00100000) >> 20;
+			
+			switch ((opcode & 0x00600000) >> 21)
+			{
+				case 0x0:
+					instruction->type = ARM_UMULL;
+					mnemonic = "UMULL";
+					break;
+				case 0x1:
+					instruction->type = ARM_UMLAL;
+					mnemonic = "UMLAL";
+					break;
+				case 0x2:
+					instruction->type = ARM_SMULL;
+					mnemonic = "SMULL";
+					break;
+				case 0x3:
+					instruction->type = ARM_SMLAL;
+					mnemonic = "SMLAL";
+					break;
+			}
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, r%i, r%i, r%i",
+						address, opcode, mnemonic, COND(opcode), (S) ? "S" : "",
+						RdLow, RdHi, Rm, Rs);
+			
+			return ERROR_OK;
+		}
+		
+		/* Swap/swap byte */
+		if ((opcode & 0x0f800000) == 0x01000000)
+		{
+			u8 Rm, Rd, Rn;
+			Rm = opcode & 0xf;
+			Rd = (opcode & 0xf000) >> 12;
+			Rn = (opcode & 0xf0000) >> 16;
+			
+			/* examine B flag */
+			instruction->type = (opcode & 0x00400000) ? ARM_SWPB : ARM_SWP;
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s r%i, r%i, [r%i]",
+					 address, opcode, (opcode & 0x00400000) ? "SWPB" : "SWP", COND(opcode), Rd, Rm, Rn);
+			return ERROR_OK;
+		}
+		
+	}
+	
+	return evaluate_misc_load_store(opcode, address, instruction);
+}
+
+int evaluate_mrs_msr(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	int R = (opcode & 0x00400000) >> 22;
+	char *PSR = (R) ? "SPSR" : "CPSR";
+		
+	/* Move register to status register (MSR) */
+	if (opcode & 0x00200000)
+	{
+		instruction->type = ARM_MSR;
+			
+		/* immediate variant */
+		if (opcode & 0x02000000)
+		{
+			u8 immediate = (opcode & 0xff);
+			u8 rotate = (opcode & 0xf00);
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tMSR%s %s_%s%s%s%s, 0x%8.8x",
+					 address, opcode, COND(opcode), PSR,
+					 (opcode & 0x10000) ? "c" : "",
+					 (opcode & 0x20000) ? "x" : "",
+					 (opcode & 0x40000) ? "s" : "",
+					 (opcode & 0x80000) ? "f" : "",
+					 ror(immediate, (rotate * 2))
+					);
+		}
+		else /* register variant */
+		{
+			u8 Rm = opcode & 0xf;
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tMSR%s %s_%s%s%s%s, r%i",
+					 address, opcode, COND(opcode), PSR,
+					 (opcode & 0x10000) ? "c" : "",
+					 (opcode & 0x20000) ? "x" : "",
+					 (opcode & 0x40000) ? "s" : "",
+					 (opcode & 0x80000) ? "f" : "",
+					 Rm
+					);
+		}
+		
+	}
+	else /* Move status register to register (MRS) */
+	{
+		u8 Rd;
+		
+		instruction->type = ARM_MRS;
+		Rd = (opcode & 0x0000f000) >> 12;
+			
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tMRS%s r%i, %s",
+				 address, opcode, COND(opcode), Rd, PSR);
+	}
+	
+	return ERROR_OK;
+}
+
+/* Miscellaneous instructions */
+int evaluate_misc_instr(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	/* MRS/MSR */
+	if ((opcode & 0x000000f0) == 0x00000000)
+	{
+		evaluate_mrs_msr(opcode, address, instruction);
+	}
+	
+	/* BX */
+	if ((opcode & 0x006000f0) == 0x00200010)
+	{
+		u8 Rm;
+		instruction->type = ARM_BX;
+		Rm = opcode & 0xf;
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tBX%s r%i",
+				 address, opcode, COND(opcode), Rm);
+	}
+	
+	/* CLZ */
+	if ((opcode & 0x0060000f0) == 0x00300010)
+	{
+		u8 Rm, Rd;
+		instruction->type = ARM_CLZ;
+		Rm = opcode & 0xf;
+		Rd = (opcode & 0xf000) >> 12;
+
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tCLZ%s r%i, r%i",
+				 address, opcode, COND(opcode), Rd, Rm);
+	}
+	
+	/* BLX */
+	if ((opcode & 0x0060000f0) == 0x00200030)
+	{
+		u8 Rm;
+		instruction->type = ARM_BLX;
+		Rm = opcode & 0xf;
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tBLX%s r%i",
+				 address, opcode, COND(opcode), Rm);
+	}
+	
+	/* Enhanced DSP add/subtracts */
+	if ((opcode & 0x0000000f0) == 0x00000050)
+	{
+		u8 Rm, Rd, Rn;
+		char *mnemonic;
+		Rm = opcode & 0xf;
+		Rd = (opcode & 0xf000) >> 12;
+		Rn = (opcode & 0xf0000) >> 16;
+		
+		switch ((opcode & 0x00600000) >> 21)
+		{
+			case 0x0:
+				instruction->type = ARM_QADD;
+				mnemonic = "QADD";
+				break;
+			case 0x1:
+				instruction->type = ARM_QSUB;
+				mnemonic = "QSUB";
+				break;
+			case 0x2:
+				instruction->type = ARM_QDADD;
+				mnemonic = "QDADD";
+				break;
+			case 0x3:
+				instruction->type = ARM_QDSUB;
+				mnemonic = "QDSUB";
+				break;
+		}
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s r%i, r%i, r%i",
+				 address, opcode, mnemonic, COND(opcode), Rd, Rm, Rn);
+	}
+	
+	/* Software breakpoints */
+	if ((opcode & 0x0000000f0) == 0x00000070)
+	{
+		u32 immediate;
+		instruction->type = ARM_BKPT;
+		immediate = ((opcode & 0x000fff00) >> 4) | (opcode & 0xf);
+		
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tBKPT 0x%4.4x",
+				 address, opcode, immediate);	
+	}
+	
+	/* Enhanced DSP multiplies */
+	if ((opcode & 0x000000090) == 0x00000080)
+	{
+		int x = (opcode & 0x20) >> 5;
+		int y = (opcode & 0x40) >> 6;
+		
+		/* SMLA<x><y> */
+		if ((opcode & 0x00600000) == 0x00000000)
+		{
+			u8 Rd, Rm, Rs, Rn;
+			instruction->type = ARM_SMLAxy;
+			Rd = (opcode & 0xf0000) >> 16;
+			Rm = (opcode & 0xf);
+			Rs = (opcode & 0xf00) >> 8;
+			Rn = (opcode & 0xf000) >> 12;
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSMLA%s%s%s r%i, r%i, r%i, r%i",
+					 address, opcode, (x) ? "T" : "B", (y) ? "T" : "B", COND(opcode),
+					 Rd, Rm, Rs, Rn);
+		}
+		
+		/* SMLAL<x><y> */
+		if ((opcode & 0x00600000) == 0x00400000)
+		{
+			u8 RdLow, RdHi, Rm, Rs;
+			instruction->type = ARM_SMLAxy;
+			RdHi = (opcode & 0xf0000) >> 16;
+			RdLow = (opcode & 0xf000) >> 12;
+			Rm = (opcode & 0xf);
+			Rs = (opcode & 0xf00) >> 8;
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSMLA%s%s%s r%i, r%i, r%i, r%i",
+					 address, opcode, (x) ? "T" : "B", (y) ? "T" : "B", COND(opcode),
+					 RdLow, RdHi, Rm, Rs);
+		}
+		
+		/* SMLAW<y> */
+		if (((opcode & 0x00600000) == 0x00100000) && (x == 0))
+		{
+			u8 Rd, Rm, Rs, Rn;
+			instruction->type = ARM_SMLAWy;
+			Rd = (opcode & 0xf0000) >> 16;
+			Rm = (opcode & 0xf);
+			Rs = (opcode & 0xf00) >> 8;
+			Rn = (opcode & 0xf000) >> 12;
+
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSMLAW%s%s r%i, r%i, r%i, r%i",
+					 address, opcode, (y) ? "T" : "B", COND(opcode),
+					 Rd, Rm, Rs, Rn);
+		}
+		
+		/* SMUL<x><y> */
+		if ((opcode & 0x00600000) == 0x00300000)
+		{
+			u8 Rd, Rm, Rs;
+			instruction->type = ARM_SMULxy;
+			Rd = (opcode & 0xf0000) >> 16;
+			Rm = (opcode & 0xf);
+			Rs = (opcode & 0xf00) >> 8;
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSMULW%s%s%s r%i, r%i, r%i",
+					 address, opcode, (x) ? "T" : "B", (y) ? "T" : "B", COND(opcode),
+					 Rd, Rm, Rs);
+		}
+		
+		/* SMULW<y> */
+		if (((opcode & 0x00600000) == 0x00100000) && (x == 1))
+		{
+			u8 Rd, Rm, Rs;
+			instruction->type = ARM_SMULWy;
+			Rd = (opcode & 0xf0000) >> 16;
+			Rm = (opcode & 0xf);
+			Rs = (opcode & 0xf00) >> 8;
+			
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tSMULW%s%s r%i, r%i, r%i",
+					 address, opcode, (y) ? "T" : "B", COND(opcode),
+					 Rd, Rm, Rs);
+		}
+	}
+	
+	return ERROR_OK;
+}
+
+int evaluate_data_proc(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	u8 I, op, S, Rn, Rd;
+	char *mnemonic;
+	char shifter_operand[32];
+	
+	I = (opcode & 0x02000000) >> 25;
+	op = (opcode & 0x01e00000) >> 21;
+	S = (opcode & 0x00100000) >> 20;
+	
+	Rd = (opcode & 0xf000) >> 12;
+	Rn = (opcode & 0xf0000) >> 16;
+	
+	switch (op)
+	{
+		case 0x0:
+			instruction->type = ARM_AND;
+			mnemonic = "AND";
+			break;
+		case 0x1:
+			instruction->type = ARM_EOR;
+			mnemonic = "EOR";
+			break;
+		case 0x2:
+			instruction->type = ARM_SUB;
+			mnemonic = "SUB";
+			break;
+		case 0x3:
+			instruction->type = ARM_RSB;
+			mnemonic = "RSB";
+			break;
+		case 0x4:
+			instruction->type = ARM_ADD;
+			mnemonic = "ADD";
+			break;
+		case 0x5:
+			instruction->type = ARM_ADC;
+			mnemonic = "ADC";
+			break;
+		case 0x6:
+			instruction->type = ARM_SBC;
+			mnemonic = "SBC";
+			break;
+		case 0x7:
+			instruction->type = ARM_RSC;
+			mnemonic = "RSC";
+			break;
+		case 0x8:
+			instruction->type = ARM_TST;
+			mnemonic = "TST";
+			break;
+		case 0x9:
+			instruction->type = ARM_TEQ;
+			mnemonic = "TEQ";
+			break;
+		case 0xa:
+			instruction->type = ARM_CMP;
+			mnemonic = "CMP";
+			break;
+		case 0xb:
+			instruction->type = ARM_CMN;
+			mnemonic = "CMN";
+			break;
+		case 0xc:
+			instruction->type = ARM_ORR;
+			mnemonic = "ORR";
+			break;
+		case 0xd:
+			instruction->type = ARM_MOV;
+			mnemonic = "MOV";
+			break;
+		case 0xe:
+			instruction->type = ARM_BIC;
+			mnemonic = "BIC";
+			break;
+		case 0xf:
+			instruction->type = ARM_MVN;
+			mnemonic = "MVN";
+			break;
+	}
+	
+	if (I) /* immediate shifter operand (#<immediate>)*/
+	{
+		u8 immed_8 = opcode & 0xff;
+		u8 rotate_imm = (opcode & 0xf00) >> 8;
+		u32 immediate;
+		
+		immediate = ror(immed_8, rotate_imm * 2);
+		
+		snprintf(shifter_operand, 32, "#0x%x", immediate);
+	}
+	else /* register-based shifter operand */
+	{
+		u8 shift, Rm;
+		shift = (opcode & 0x60) >> 5;
+		Rm = (opcode & 0xf);
+		
+		if ((opcode & 0x10) != 0x10) /* Immediate shifts ("<Rm>" or "<Rm>, <shift> #<shift_immediate>") */
+		{
+			u8 shift_imm;
+			shift_imm = (opcode & 0xf80) >> 7;
+
+			
+			if ((shift_imm == 0x0) && (shift == 0x0))
+			{
+				snprintf(shifter_operand, 32, "r%i", Rm);
+			}
+			else
+			{
+				if (shift == 0x0) /* LSL */
+				{
+					snprintf(shifter_operand, 32, "r%i, LSL #0x%x", Rm, shift_imm);
+				}
+				else if (shift == 0x1) /* LSR */
+				{
+					if (shift_imm == 0x0)
+						shift_imm = 0x32;
+					snprintf(shifter_operand, 32, "r%i, LSR #0x%x", Rm, shift_imm);
+				}
+				else if (shift == 0x2) /* ASR */
+				{
+					if (shift_imm == 0x0)
+						shift_imm = 0x32;
+					snprintf(shifter_operand, 32, "r%i, ASR #0x%x", Rm, shift_imm);
+				}
+				else if (shift == 0x3) /* ROR or RRX */
+				{
+					if (shift_imm == 0x0) /* RRX */
+						snprintf(shifter_operand, 32, "r%i, RRX", Rm);
+					else
+						snprintf(shifter_operand, 32, "r%i, ROR #0x%x", Rm, shift_imm);
+				}
+			}
+		}
+		else /* Register shifts ("<Rm>, <shift> <Rs>") */
+		{
+			u8 Rs = (opcode & 0xf00) >> 8;
+			
+			if (shift == 0x0) /* LSL */
+			{
+				snprintf(shifter_operand, 32, "r%i, LSL r%i", Rm, Rs);
+			}
+			else if (shift == 0x1) /* LSR */
+			{
+				snprintf(shifter_operand, 32, "r%i, LSR r%i", Rm, Rs);
+			}
+			else if (shift == 0x2) /* ASR */
+			{
+				snprintf(shifter_operand, 32, "r%i, ASR r%i", Rm, Rs);
+			}
+			else if (shift == 0x3) /* ROR or RRX */
+			{
+				snprintf(shifter_operand, 32, "r%i, ROR r%i", Rm, Rs);
+			}
+		}
+	}
+	
+	if ((op < 0x8) || (op == 0xc) || (op == 0xe)) /* <opcode3>{<cond>}{S} <Rd>, <Rn>, <shifter_operand> */
+	{
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, r%i, %s",
+				 address, opcode, mnemonic, COND(opcode),
+				 (S) ? "S" : "", Rd, Rn, shifter_operand);
+	}
+	else if ((op == 0xd) || (op == 0xf)) /* <opcode1>{<cond>}{S} <Rd>, <shifter_operand> */
+	{
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s%s r%i, %s",
+				 address, opcode, mnemonic, COND(opcode),
+				 (S) ? "S" : "", Rd, shifter_operand);
+	}
+	else /* <opcode2>{<cond>} <Rn>, <shifter_operand> */
+	{
+		snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\t%s%s r%i, %s",
+				 address, opcode, mnemonic, COND(opcode),
+				 Rn, shifter_operand);
+	}
+	
+	return ERROR_OK;
+}
+		
+int evaluate_opcode(u32 opcode, u32 address, arm_instruction_t *instruction)
+{
+	/* clear fields, to avoid confusion */
+	bzero(instruction, sizeof(arm_instruction_t));
+	instruction->opcode = opcode;
+	
+	/* catch opcodes with condition field [31:28] = b1111 */
+	if ((opcode & 0xf0000000) == 0xf0000000)
+	{
+		/* Undefined instruction (or ARMv5E cache preload PLD) */
+		if ((opcode & 0x08000000) == 0x00000000)
+			return evaluate_pld(opcode, address, instruction);
+		
+		/* Undefined instruction */
+		if ((opcode & 0x0e000000) == 0x08000000)
+		{
+			instruction->type = ARM_UNDEFINED_INSTRUCTION;
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tUNDEFINED INSTRUCTION", address, opcode);
+			return ERROR_OK;
+		}
+		
+		/* Branch and branch with link and change to Thumb */
+		if ((opcode & 0x0e000000) == 0x0a000000)
+			return evaluate_blx_imm(opcode, address, instruction);
+		
+		/* Extended coprocessor opcode space (ARMv5 and higher )*/
+		/* Coprocessor load/store and double register transfers */
+		if ((opcode & 0x0e000000) == 0x0c000000)
+			return evaluate_ldc_stc_mcrr_mrrc(opcode, address, instruction);
+		
+		/* Coprocessor data processing */
+		if ((opcode & 0x0f000100) == 0x0c000000)
+			return evaluate_cdp_mcr_mrc(opcode, address, instruction);
+		
+		/* Coprocessor register transfers */
+		if ((opcode & 0x0f000010) == 0x0c000010)
+			return evaluate_cdp_mcr_mrc(opcode, address, instruction);
+		
+		/* Undefined instruction */
+		if ((opcode & 0x0f000000) == 0x0f000000)
+		{
+			instruction->type = ARM_UNDEFINED_INSTRUCTION;
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tUNDEFINED INSTRUCTION", address, opcode);
+			return ERROR_OK;
+		}
+	}
+	
+	/* catch opcodes with [27:25] = b000 */
+	if ((opcode & 0x0e000000) == 0x00000000)
+	{
+		/* Multiplies, extra load/stores */
+		if ((opcode & 0x00000090) == 0x00000090)
+			return evaluate_mul_and_extra_ld_st(opcode, address, instruction);
+		
+		/* Miscellaneous instructions */
+		if ((opcode & 0x0f900000) == 0x01000000)
+			return evaluate_misc_instr(opcode, address, instruction);
+		
+		return evaluate_data_proc(opcode, address, instruction);
+	}
+	
+	/* catch opcodes with [27:25] = b001 */
+	if ((opcode & 0x0e000000) == 0x02000000)
+	{
+		/* Undefined instruction */
+		if ((opcode & 0x0fb00000) == 0x03000000)
+		{
+			instruction->type = ARM_UNDEFINED_INSTRUCTION;
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tUNDEFINED INSTRUCTION", address, opcode);
+			return ERROR_OK;
+		}
+				
+		/* Move immediate to status register */
+		if ((opcode & 0x0fb00000) == 0x03200000)
+			return evaluate_mrs_msr(opcode, address, instruction);
+		
+		return evaluate_data_proc(opcode, address, instruction);
+
+	}
+	
+	/* catch opcodes with [27:25] = b010 */
+	if ((opcode & 0x0e000000) == 0x04000000)
+	{
+		/* Load/store immediate offset */
+		return evaluate_load_store(opcode, address, instruction);
+	}
+	
+	/* catch opcodes with [27:25] = b011 */
+	if ((opcode & 0x0e000000) == 0x04000000)
+	{
+		/* Undefined instruction */
+		if ((opcode & 0x00000010) == 0x00000010)
+		{
+			instruction->type = ARM_UNDEFINED_INSTRUCTION;
+			snprintf(instruction->text, 128, "0x%8.8x\t0x%8.8x\tUNDEFINED INSTRUCTION", address, opcode);
+			return ERROR_OK;
+		}
+		
+		/* Load/store register offset */
+		return evaluate_load_store(opcode, address, instruction);
+
+	}
+	
+	/* catch opcodes with [27:25] = b100 */
+	if ((opcode & 0x0e000000) == 0x08000000)
+	{
+		/* Load/store multiple */
+		return evaluate_ldm_stm(opcode, address, instruction);
+	}
+	
+	/* catch opcodes with [27:25] = b101 */
+	if ((opcode & 0x0e000000) == 0x0a000000)
+	{
+		/* Branch and branch with link */
+		return evaluate_b_bl(opcode, address, instruction);
+	}
+	
+	/* catch opcodes with [27:25] = b110 */
+	if ((opcode & 0x0e000000) == 0x0a000000)
+	{
+		/* Coprocessor load/store and double register transfers */
+		return evaluate_ldc_stc_mcrr_mrrc(opcode, address, instruction);
+	}
+	
+	/* catch opcodes with [27:25] = b111 */
+	if ((opcode & 0x0e000000) == 0x0e000000)
+	{
+		/* Software interrupt */
+		if ((opcode & 0x0f000000) == 0x0f000000)
+			return evaluate_swi(opcode, address, instruction);
+		
+		/* Coprocessor data processing */
+		if ((opcode & 0x0f000010) == 0x0e000000)
+			return evaluate_cdp_mcr_mrc(opcode, address, instruction);
+		
+		/* Coprocessor register transfers */
+		if ((opcode & 0x0f000010) == 0x0e000010)
+			return evaluate_cdp_mcr_mrc(opcode, address, instruction);
+	}
+	
+	ERROR("should never reach this point");
+	return -1;
+}
diff --git a/src/target/arm_disassembler.h b/src/target/arm_disassembler.h
new file mode 100644
index 00000000..df84ba0f
--- /dev/null
+++ b/src/target/arm_disassembler.h
@@ -0,0 +1,138 @@
+/***************************************************************************
+ *   Copyright (C) 2006 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   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, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#ifndef ARM_DISASSEMBLER_H
+#define ARM_DISASSEMBLER_H
+
+#include "types.h"
+
+enum arm_instruction_type
+{
+	ARM_UNKNOWN_INSTUCTION,
+	
+	/* Branch instructions */
+	ARM_B,
+	ARM_BL,
+	ARM_BX,
+	ARM_BLX,
+	
+	/* Data processing instructions */
+	ARM_AND,
+	ARM_EOR,
+	ARM_SUB,
+	ARM_RSB,
+	ARM_ADD,
+	ARM_ADC,
+	ARM_SBC,
+	ARM_RSC,
+	ARM_TST,
+	ARM_TEQ,
+	ARM_CMP,
+	ARM_CMN,
+	ARM_ORR,
+	ARM_MOV,
+	ARM_BIC,
+	ARM_MVN,
+	
+	/* Load/store instructions */
+	ARM_LDR,
+	ARM_LDRB,
+	ARM_LDRT,
+	ARM_LDRBT,
+	
+	ARM_LDRH,
+	ARM_LDRSB,
+	ARM_LDRSH,
+	
+	ARM_LDM,
+
+	ARM_STR,
+	ARM_STRB,
+	ARM_STRT,
+	ARM_STRBT,
+	
+	ARM_STRH,
+	
+	ARM_STM,
+	
+	/* Status register access instructions */
+	ARM_MRS,
+	ARM_MSR,
+	
+	/* Multiply instructions */
+	ARM_MUL,
+	ARM_MLA,
+	ARM_SMULL,
+	ARM_SMLAL,
+	ARM_UMULL,
+	ARM_UMLAL,
+	
+	/* Miscellaneous instructions */
+	ARM_CLZ,
+	
+	/* Exception generating instructions */
+	ARM_BKPT,
+	ARM_SWI,
+	
+	/* Coprocessor instructions */
+	ARM_CDP,
+	ARM_LDC,
+	ARM_STC,
+	ARM_MCR,
+	ARM_MRC,
+	
+	/* Semaphore instructions */
+	ARM_SWP,
+	ARM_SWPB,
+	
+	/* Enhanced DSP extensions */
+	ARM_MCRR,
+	ARM_MRRC,
+	ARM_PLD,
+	ARM_QADD,
+	ARM_QDADD,
+	ARM_QSUB,
+	ARM_QDSUB,
+	ARM_SMLAxy,
+	ARM_SMLALxy,
+	ARM_SMLAWy,
+	ARM_SMULxy,
+	ARM_SMULWy,
+	ARM_LDRD,
+	ARM_STRD,
+
+	ARM_UNDEFINED_INSTRUCTION = 0xffffffff,
+};
+
+typedef struct arm_instruction_s
+{
+	enum arm_instruction_type type;
+	char text[128];
+	u32 opcode;
+	
+	/* target */
+	u32 target_address;
+	
+} arm_instruction_t;
+
+extern int evaluate_opcode(u32 opcode, u32 address, arm_instruction_t *instruction);
+
+#define COND(opcode) (arm_condition_strings[(opcode & 0xf0000000)>>28])
+
+#endif /* ARM_DISASSEMBLER_H */
diff --git a/src/target/armv4_5.c b/src/target/armv4_5.c
index 51fd4b42..4932e20a 100644
--- a/src/target/armv4_5.c
+++ b/src/target/armv4_5.c
@@ -19,6 +19,8 @@
  ***************************************************************************/
 #include "config.h"
 
+#include "arm_disassembler.h"
+
 #include "armv4_5.h"
 
 #include "target.h"
@@ -377,6 +379,47 @@ int handle_armv4_5_core_state_command(struct command_context_s *cmd_ctx, char *c
 	return ERROR_OK;
 }
 
+int handle_armv4_5_disassemble_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+{
+	target_t *target = get_current_target(cmd_ctx);
+	armv4_5_common_t *armv4_5 = target->arch_info;
+	u32 address;
+	int count;
+	int i;
+	arm_instruction_t cur_instruction;
+	u32 opcode;
+	int thumb;
+	
+	if (armv4_5->common_magic != ARMV4_5_COMMON_MAGIC)
+	{
+		command_print(cmd_ctx, "current target isn't an ARMV4/5 target");
+		return ERROR_OK;
+	}
+	
+	if (argc < 2)
+	{
+		command_print(cmd_ctx, "usage: armv4_5 disassemble <address> <count> ['thumb']");
+		return ERROR_OK;
+	}
+	
+	address = strtoul(args[0], NULL, 0);
+	count = strtoul(args[1], NULL, 0);
+	
+	if (argc >= 3)
+		if (strcmp(args[2], "thumb") == 0)
+			thumb = 1;
+	
+	for (i = 0; i < count; i++)
+	{
+		target->type->read_memory(target, address, 4, 1, (u8*)&opcode);
+		evaluate_opcode(opcode, address, &cur_instruction);
+		command_print(cmd_ctx, "%s", cur_instruction.text);
+		address += (thumb) ? 2 : 4;
+	}
+	
+	return ERROR_OK;
+}
+
 int armv4_5_register_commands(struct command_context_s *cmd_ctx)
 {
 	command_t *armv4_5_cmd;
@@ -386,6 +429,7 @@ int armv4_5_register_commands(struct command_context_s *cmd_ctx)
 	register_command(cmd_ctx, armv4_5_cmd, "reg", handle_armv4_5_reg_command, COMMAND_EXEC, "display ARM core registers");
 	register_command(cmd_ctx, armv4_5_cmd, "core_state", handle_armv4_5_core_state_command, COMMAND_EXEC, "display/change ARM core state <arm|thumb>");
 	
+	register_command(cmd_ctx, armv4_5_cmd, "disassemble", handle_armv4_5_disassemble_command, COMMAND_EXEC, "disassemble instructions <address> <count> ['thumb']");
 	return ERROR_OK;
 }