diff --git a/drivers/bios_emulator/besys.c b/drivers/bios_emulator/besys.c
index 8e29a9e..752a928 100644
--- a/drivers/bios_emulator/besys.c
+++ b/drivers/bios_emulator/besys.c
@@ -60,6 +60,14 @@ static u8 BE_model = 0xFC;
 static u8 BE_submodel = 0x00;
 #endif
 
+#undef DEBUG_IO_ACCESS
+
+#ifdef DEBUG_IO_ACCESS
+#define debug_io(fmt, ...)	printf(fmt, ##__VA_ARGS__)
+#else
+#define debug_io(x, b...)
+#endif
+
 /*----------------------------- Implementation ----------------------------*/
 
 /****************************************************************************
@@ -96,15 +104,15 @@ static u8 *BE_memaddr(u32 addr)
 #else
 	else if (addr >= 0xFFFF5 && addr < 0xFFFFE) {
 		/* Return a faked BIOS date string for non-x86 machines */
-		DB(printf("BE_memaddr - Returning BIOS date\n");)
+		debug_io("BE_memaddr - Returning BIOS date\n");
 		return (u8 *)(BE_biosDate + addr - 0xFFFF5);
 	} else if (addr == 0xFFFFE) {
 		/* Return system model identifier for non-x86 machines */
-		DB(printf("BE_memaddr - Returning model\n");)
+		debug_io("BE_memaddr - Returning model\n");
 		return &BE_model;
 	} else if (addr == 0xFFFFF) {
 		/* Return system submodel identifier for non-x86 machines */
-		DB(printf("BE_memaddr - Returning submodel\n");)
+		debug_io("BE_memaddr - Returning submodel\n");
 		return &BE_submodel;
 	}
 #endif
@@ -260,6 +268,7 @@ static u8 VGA_inpb (const int port)
 {
 	u8 val = 0xff;
 
+	debug_io("vga_inb.%04X -> ", (u16) port);
 	switch (port) {
 	case 0x3C0:
 		/* 3C0 has funky characteristics because it can act as either
@@ -583,7 +592,12 @@ u8 X86API BE_inb(X86EMU_pioAddr port)
 		val = LOG_inpb(port);
 	} else
 #endif
+	{
+		debug_io("inb.%04X -> ", (u16) port);
 		val = LOG_inpb(port);
+		debug_io("%02X\n", val);
+	}
+
 	return val;
 }
 
@@ -611,7 +625,12 @@ u16 X86API BE_inw(X86EMU_pioAddr port)
 		val = LOG_inpw(port);
 	} else
 #endif
+	{
+		debug_io("inw.%04X -> ", (u16) port);
 		val = LOG_inpw(port);
+		debug_io("%04X\n", val);
+	}
+
 	return val;
 }
 
@@ -638,7 +657,12 @@ u32 X86API BE_inl(X86EMU_pioAddr port)
 		val = LOG_inpd(port);
 	} else
 #endif
+	{
+		debug_io("inl.%04X -> ", (u16) port);
 		val = LOG_inpd(port);
+		debug_io("%08X\n", val);
+	}
+
 	return val;
 }
 
@@ -670,7 +694,11 @@ void X86API BE_outb(X86EMU_pioAddr port, u8 val)
 		LOG_outpb(port, val);
 	} else
 #endif
+	{
+		debug_io("outb.%04X <- %02X", (u16) port, val);
 		LOG_outpb(port, val);
+		debug_io("\n");
+	}
 }
 
 /****************************************************************************
@@ -686,18 +714,22 @@ through to the real hardware if we don't need to special case it.
 void X86API BE_outw(X86EMU_pioAddr port, u16 val)
 {
 #if !defined(CONFIG_X86EMU_RAW_IO)
-		if (IS_VGA_PORT(port)) {
-			VGA_outpb(port, val);
-			VGA_outpb(port + 1, val >> 8);
-		} else if (IS_PCI_PORT(port))
-			PCI_outp(port, val, REG_WRITE_WORD);
-		else if (port < 0x100) {
-			DB(printf("WARN: MAybe INVALID outw.%04X <- %04X\n", (u16) port,
-			       val);)
-			LOG_outpw(port, val);
-		} else
+	if (IS_VGA_PORT(port)) {
+		VGA_outpb(port, val);
+		VGA_outpb(port + 1, val >> 8);
+	} else if (IS_PCI_PORT(port)) {
+		PCI_outp(port, val, REG_WRITE_WORD);
+	} else if (port < 0x100) {
+		DB(printf("WARN: MAybe INVALID outw.%04X <- %04X\n", (u16)port,
+			  val);)
+		LOG_outpw(port, val);
+	} else
 #endif
-			LOG_outpw(port, val);
+	{
+		debug_io("outw.%04X <- %04X", (u16) port, val);
+		LOG_outpw(port, val);
+		debug_io("\n");
+	}
 }
 
 /****************************************************************************
@@ -720,5 +752,9 @@ void X86API BE_outl(X86EMU_pioAddr port, u32 val)
 		LOG_outpd(port, val);
 	} else
 #endif
+	{
+		debug_io("outl.%04X <- %08X", (u16) port, val);
 		LOG_outpd(port, val);
+		debug_io("\n");
+	}
 }
diff --git a/drivers/bios_emulator/bios.c b/drivers/bios_emulator/bios.c
index bcc192f..152d70a 100644
--- a/drivers/bios_emulator/bios.c
+++ b/drivers/bios_emulator/bios.c
@@ -84,14 +84,14 @@ static void X86API int42(int intno)
 			PM_outpb(0x3c2, PM_inpb(0x3cc) & (u8) ~ 0x02);
 			return;
 		}
-#ifdef  DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 		else {
 			printf("int42: unknown function AH=0x12, BL=0x32, AL=%#02x\n",
 			     M.x86.R_AL);
 		}
 #endif
 	}
-#ifdef  DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 	else {
 		printf("int42: unknown function AH=%#02x, AL=%#02x, BL=%#02x\n",
 		     M.x86.R_AH, M.x86.R_AL, M.x86.R_BL);
diff --git a/drivers/bios_emulator/biosemui.h b/drivers/bios_emulator/biosemui.h
index 8c1f111..7853015 100644
--- a/drivers/bios_emulator/biosemui.h
+++ b/drivers/bios_emulator/biosemui.h
@@ -48,7 +48,7 @@
 #include <asm/io.h>
 /*---------------------- Macros and type definitions ----------------------*/
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 #define DB(x)	x
 #else
 #define DB(x)	do{}while(0);
diff --git a/drivers/bios_emulator/include/x86emu.h b/drivers/bios_emulator/include/x86emu.h
index 63febe0..b28cdc6 100644
--- a/drivers/bios_emulator/include/x86emu.h
+++ b/drivers/bios_emulator/include/x86emu.h
@@ -161,7 +161,7 @@ extern "C" {			/* Use "C" linkage when in C++ mode */
 	void X86EMU_exec(void);
 	void X86EMU_halt_sys(void);
 
-#ifdef  DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 #define HALT_SYS()  \
     printf("halt_sys: file %s, line %d\n", __FILE__, __LINE__), \
     X86EMU_halt_sys()
diff --git a/drivers/bios_emulator/include/x86emu/debug.h b/drivers/bios_emulator/include/x86emu/debug.h
index 268c9d3..12d6c7f 100644
--- a/drivers/bios_emulator/include/x86emu/debug.h
+++ b/drivers/bios_emulator/include/x86emu/debug.h
@@ -48,7 +48,7 @@
 #define CHECK_MEM_ACCESS_F		0x4	/*using regular linear pointer */
 #define CHECK_DATA_ACCESS_F		0x8	/*using segment:offset */
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 # define CHECK_IP_FETCH()		(M.x86.check & CHECK_IP_FETCH_F)
 # define CHECK_SP_ACCESS()		(M.x86.check & CHECK_SP_ACCESS_F)
 # define CHECK_MEM_ACCESS()		(M.x86.check & CHECK_MEM_ACCESS_F)
@@ -60,7 +60,7 @@
 # define CHECK_DATA_ACCESS()
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 # define DEBUG_INSTRUMENT()	(M.x86.debug & DEBUG_INSTRUMENT_F)
 # define DEBUG_DECODE()		(M.x86.debug & DEBUG_DECODE_F)
 # define DEBUG_TRACE()		(M.x86.debug & DEBUG_TRACE_F)
@@ -99,7 +99,7 @@
 # define DEBUG_DECODE_NOPRINT() 0
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 
 # define DECODE_PRINTF(x)	if (DEBUG_DECODE()) \
 				    x86emu_decode_printf(x)
@@ -129,7 +129,7 @@
 # define SAVE_IP_CS(x,y)
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 #define TRACE_REGS()					    \
     if (DEBUG_DISASSEMBLE()) {				    \
 	x86emu_just_disassemble();			    \
@@ -140,7 +140,7 @@
 # define TRACE_REGS()
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 # define SINGLE_STEP()	    if (DEBUG_STEP()) x86emu_single_step()
 #else
 # define SINGLE_STEP()
@@ -150,7 +150,7 @@
     TRACE_REGS();	    \
     SINGLE_STEP()
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 # define START_OF_INSTR()
 # define END_OF_INSTR()	    EndOfTheInstructionProcedure: x86emu_end_instr();
 # define END_OF_INSTR_NO_TRACE()    x86emu_end_instr();
@@ -160,7 +160,7 @@
 # define END_OF_INSTR_NO_TRACE()
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 # define  CALL_TRACE(u,v,w,x,s)					\
     if (DEBUG_TRACECALLREGS())					\
 	x86emu_dump_regs();					\
@@ -176,7 +176,7 @@
 # define RETURN_TRACE(n,u,v)
 #endif
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 #define DB(x)	x
 #else
 #define DB(x)
diff --git a/drivers/bios_emulator/include/x86emu/regs.h b/drivers/bios_emulator/include/x86emu/regs.h
index a7fedd2..2934129 100644
--- a/drivers/bios_emulator/include/x86emu/regs.h
+++ b/drivers/bios_emulator/include/x86emu/regs.h
@@ -282,7 +282,7 @@ typedef struct {
 	u8 intno;
 	volatile int intr;	/* mask of pending interrupts */
 	int debug;
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 	int check;
 	u16 saved_ip;
 	u16 saved_cs;
diff --git a/drivers/bios_emulator/x86emu/debug.c b/drivers/bios_emulator/x86emu/debug.c
index 2ec64c2..27e90e4 100644
--- a/drivers/bios_emulator/x86emu/debug.c
+++ b/drivers/bios_emulator/x86emu/debug.c
@@ -44,7 +44,7 @@
 
 /*----------------------------- Implementation ----------------------------*/
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 
 static void print_encoded_bytes(u16 s, u16 o);
 static void print_decoded_instruction(void);
diff --git a/drivers/bios_emulator/x86emu/decode.c b/drivers/bios_emulator/x86emu/decode.c
index a782b81..da44c3d 100644
--- a/drivers/bios_emulator/x86emu/decode.c
+++ b/drivers/bios_emulator/x86emu/decode.c
@@ -303,7 +303,7 @@ NOTE: Do not inline this function as (*sys_rdX) is already inline!
 u8 fetch_data_byte(
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -322,7 +322,7 @@ NOTE: Do not inline this function as (*sys_rdX) is already inline!
 u16 fetch_data_word(
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -341,7 +341,7 @@ NOTE: Do not inline this function as (*sys_rdX) is already inline!
 u32 fetch_data_long(
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -362,7 +362,7 @@ u8 fetch_data_byte_abs(
     uint segment,
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
@@ -383,7 +383,7 @@ u16 fetch_data_word_abs(
     uint segment,
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
@@ -404,7 +404,7 @@ u32 fetch_data_long_abs(
     uint segment,
     uint offset)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
@@ -426,7 +426,7 @@ void store_data_byte(
     uint offset,
     u8 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -448,7 +448,7 @@ void store_data_word(
     uint offset,
     u16 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -470,7 +470,7 @@ void store_data_long(
     uint offset,
     u32 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access((u16)get_data_segment(), offset);
 #endif
@@ -493,7 +493,7 @@ void store_data_byte_abs(
     uint offset,
     u8 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
@@ -516,7 +516,7 @@ void store_data_word_abs(
     uint offset,
     u16 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
@@ -539,7 +539,7 @@ void store_data_long_abs(
     uint offset,
     u32 val)
 {
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (CHECK_DATA_ACCESS())
 	x86emu_check_data_access(segment, offset);
 #endif
diff --git a/drivers/bios_emulator/x86emu/ops.c b/drivers/bios_emulator/x86emu/ops.c
index f8e093d..c853260 100644
--- a/drivers/bios_emulator/x86emu/ops.c
+++ b/drivers/bios_emulator/x86emu/ops.c
@@ -79,7 +79,7 @@
 
 /* constant arrays to do several instructions in just one function */
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 static char *x86emu_GenOpName[8] = {
     "ADD", "OR", "ADC", "SBB", "AND", "SUB", "XOR", "CMP"};
 #endif
@@ -160,7 +160,7 @@ static u32 (*opcD1_long_operation[])(u32 s, u8 d) =
     sar_long,
 };
 
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
 
 static char *opF6_names[8] =
   { "TEST\t", "", "NOT\t", "NEG\t", "MUL\t", "IMUL\t", "DIV\t", "IDIV\t" };
@@ -1281,7 +1281,7 @@ void x86emuOp_opc80_byte_RM_IMM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -1359,7 +1359,7 @@ void x86emuOp_opc81_word_RM_IMM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -1475,7 +1475,7 @@ void x86emuOp_opc82_byte_RM_IMM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -1551,7 +1551,7 @@ void x86emuOp_opc83_word_RM_IMM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3083,7 +3083,7 @@ void x86emuOp_opcC0_byte_RM_MEM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3158,7 +3158,7 @@ void x86emuOp_opcC1_word_RM_MEM(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3630,7 +3630,7 @@ void x86emuOp_opcD0_byte_RM_1(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3701,7 +3701,7 @@ void x86emuOp_opcD1_word_RM_1(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3803,7 +3803,7 @@ void x86emuOp_opcD2_byte_RM_CL(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -3876,7 +3876,7 @@ void x86emuOp_opcD3_word_RM_CL(u8 X86EMU_UNUSED(op1))
      */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -4859,7 +4859,7 @@ void x86emuOp_opcFE_byte_RM(u8 X86EMU_UNUSED(op1))
     /* Yet another special case instruction. */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings
@@ -4923,7 +4923,7 @@ void x86emuOp_opcFF_word_RM(u8 X86EMU_UNUSED(op1))
     /* Yet another special case instruction. */
     START_OF_INSTR();
     FETCH_DECODE_MODRM(mod, rh, rl);
-#ifdef DEBUG
+#ifdef CONFIG_X86EMU_DEBUG
     if (DEBUG_DECODE()) {
 	/* XXX DECODE_PRINTF may be changed to something more
 	   general, so that it is important to leave the strings