diff --git a/src/bootloader/Makefile b/src/bootloader/Makefile
index a24adc5..6379939 100644
--- a/src/bootloader/Makefile
+++ b/src/bootloader/Makefile
@@ -1,9 +1,15 @@
-ENDIAN='big'
+# environment vaiables read:
+# BOARD = {ml402, denano}
+# TLB = {no, yes}
+# ENDIANESS = {eb, el}
+BOARD ?= ml402
+TLB ?= no
+ENDIANESS ?= eb
 
-ifeq ($(ENDIAN), 'big')
-  ENDIAN_FLAGS=-EB
-else
+ifeq ($(ENDIANESS),el)
   ENDIAN_FLAGS=-EL
+else
+  ENDIAN_FLAGS=-EB
 endif
 
 CFLAGS=$(ENDIAN_FLAGS) -Os -I. -I../ -I../libsys -msoft-float -march=r3000 -G0
@@ -17,6 +23,8 @@ else
   LFLAGS+=-T bootloader.ld
 endif
 
+BUILD_DIR=./build/$(BOARD)/$(ENDIANESS)
+		  
 LIBS=-lc -lgcc
 CFLAGS += -DXCP_SIZE=4096
 		  
@@ -28,40 +36,40 @@ ROMGEN=$(MIPS_HOME)/tools/romgen
 
 .PHONY: libsys
 
-all: bootloader_flash
+all: $(BUILD_DIR) $(BUILD_DIR)/bootloader.elf $(BUILD_DIR)/bootloader_with_flash.elf
 
-libsys: startup_boot.S kernel_boot.S libsys_boot.c
-	$(CC) $(CFLAGS) -c startup_boot.S -o startup.o
-	$(CC) $(CFLAGS) -c kernel_boot.S -o kernel.o
-	$(CC) $(CFLAGS) -c libsys_boot.c -o libsys.o
+OBJS-ml402=$(addprefix $(BUILD_DIR)/, startup.o kernel.o libsys.o)
+OBJS-denano=$(addprefix $(BUILD_DIR)/, startup.o kernel.o libsys.o)
+		
+$(BUILD_DIR)/%.o : %.c
+	$(CC) $(CFLAGS) -c -o $@ $<
 
-bootloader: libsys bootloader.c
+$(BUILD_DIR)/%.o : %.S
+	$(CC) $(CFLAGS) -c -o $@ $<
+		  
+$(BUILD_DIR)/bootloader.elf: $(OBJS-$(BOARD)) bootloader.c
 	$(CC) $(CFLAGS) -g -c bootloader.c
-	$(LD) $(LFLAGS) $(LIB_DIRS) startup.o kernel.o libsys.o bootloader.o -o $@.elf $(LIBS) >$@.map
+	$(LD) $(LFLAGS) $(LIB_DIRS) $(OBJS-$(BOARD)) bootloader.o -o $@.elf $(LIBS) >$@.map
 	$(OBJDUMP) -D $@.elf > $@.dis
 	$(OBJCOPY) $@.elf -j ROM --output-target=binary $@.ROM.bin
 	$(OBJCOPY) -O srec $@.elf $@.srec
 	$(ROMGEN) $@.ROM.bin 11 $(ENDIAN_FLAGS)
-
-bootloader_flash: libsys bootloader_with_flash.c
+		  
+$(BUILD_DIR)/bootloader_with_flash.elf: $(OBJS-$(BOARD)) bootloader_with_flash.c ../cfiflash.c
 	$(CC) $(CFLAGS) -g -c bootloader_with_flash.c
 	$(CC) $(CFLAGS) -g -c ../cfiflash.c
-	$(LD) $(LFLAGS) $(LIB_DIRS) startup.o kernel.o libsys.o cfiflash.o bootloader_with_flash.o -o $@.elf $(LIBS) >$@.map
+	$(LD) $(LFLAGS) $(LIB_DIRS) $(OBJS-$(BOARD)) cfiflash.o bootloader_with_flash.o -o $@.elf $(LIBS) >$@.map
 	$(OBJDUMP) -D $@.elf > $@.dis
 	$(OBJCOPY) $@.elf -j ROM --output-target=binary $@.ROM.bin
 	$(OBJCOPY) -O srec $@.elf $@.srec
 	$(ROMGEN) $@.ROM.bin 11 $(ENDIAN_FLAGS)
 
-test: libsys test.c ../libsys/irq.c ../libsys/kernel.S ../libsys/xcpt.c
-	$(CC) $(CFLAGS) -g -c test.c
-	$(CC) $(CFLAGS) -g -c ../libsys/irq.c
-	$(CC) $(CFLAGS) -g -c ../libsys/kernel.S
-	$(CC) $(CFLAGS) -c ../libsys/xcpt.c -o xcpt.o
-	$(LD) $(LFLAGS) $(LIB_DIRS) startup.o kernel.o irq.o xcpt.o libsys.o test.o -o $@.elf $(LIBS) >$@.map
-	$(OBJDUMP) -D $@.elf > $@.dis
-	$(OBJCOPY) $@.elf -j ROM --output-target=binary $@.ROM.bin
-	$(OBJCOPY) -O ihex -I binary $@.ROM.bin $@.ihex
-	$(ROMGEN) $@.ROM.bin 11 $(ENDIAN_FLAGS)
+$(BUILD_DIR):
+	mkdir -p $(BUILD_DIR)
 
 clean:
-	rm -rf *.o *.bin *.map *.dis *.srec *.elf *.vhd* *.tcl bootloader > /dev/null
+	rm -rf $(BUILD_DIR)/*.* > /dev/null
+
+mrproper:
+	rm -rf $(BUILD_DIR)
+		  
diff --git a/src/bootloader/bootloader.c b/src/bootloader/bootloader.c
index 5eff98a..1003664 100644
--- a/src/bootloader/bootloader.c
+++ b/src/bootloader/bootloader.c
@@ -1,4 +1,4 @@
-#include "libsys_boot.h"
+#include "libsys.h"
 
 #define	MAGIC_EB	0x4A464931	// "JFI1" in big-endian;
 #define	MAGIC_EL	0x3149464A	// "JFI1" in little-endian;
diff --git a/src/bootloader/bootloader_with_flash.c b/src/bootloader/bootloader_with_flash.c
index 957d1be..3da6e81 100644
--- a/src/bootloader/bootloader_with_flash.c
+++ b/src/bootloader/bootloader_with_flash.c
@@ -1,4 +1,4 @@
-#include "libsys_boot.h"
+#include "libsys.h"
 #include "cfiflash.h"
 
 #define	MAGIC_EB	0x4A464931	// "JFI1" in big-endian;
diff --git a/src/bootloader/kernel_boot.S b/src/bootloader/kernel.S
similarity index 100%
rename from src/bootloader/kernel_boot.S
rename to src/bootloader/kernel.S
diff --git a/src/bootloader/libsys_boot.c b/src/bootloader/libsys.c
similarity index 93%
rename from src/bootloader/libsys_boot.c
rename to src/bootloader/libsys.c
index ad246db..62f9c5a 100644
--- a/src/bootloader/libsys_boot.c
+++ b/src/bootloader/libsys.c
@@ -4,7 +4,7 @@
 #include <sys/stat.h>
 #include <errno.h>
 #include <stdlib.h>
-#include "libsys_boot.h"
+#include "libsys.h"
 
 // ---------------------------------------------------------------------------------
 void _exit(int reason)
diff --git a/src/bootloader/libsys_boot.h b/src/bootloader/libsys.h
similarity index 100%
rename from src/bootloader/libsys_boot.h
rename to src/bootloader/libsys.h
diff --git a/src/bootloader/startup_boot.S b/src/bootloader/startup.S
similarity index 100%
rename from src/bootloader/startup_boot.S
rename to src/bootloader/startup.S
diff --git a/src/bootloader/test.c b/src/bootloader/test.c
deleted file mode 100644
index 534bb88..0000000
--- a/src/bootloader/test.c
+++ /dev/null
@@ -1,199 +0,0 @@
-#include "libsys_boot.h"
-
-#define ARRAY_SIZE(a)	(sizeof(a)/sizeof(*a))
-#define SDRAM_SIZE		(256)
-
-void uart_isr(void)
-{
-	volatile uint32_t *pUART0_stat = (uint32_t*)SYS_UART_STAT;
-	volatile uint32_t *pUART0_data = (uint32_t*)SYS_UART_DATA;
-
-	while(0x200 & *pUART0_stat)
-	{
-		char data = (char)*pUART0_data;
-		sputs(&data);
-	}
-}
-
-void timer_isr(void)
-{
-	static uint8_t led = 0;
-
-	volatile uint32_t *pTim_stat = (uint32_t*)SYS_ITIM_STAT;
-	volatile uint32_t *pTim_ctrl = (uint32_t*)SYS_ITIM_CTRL;
-	volatile uint32_t *pGPIO = (uint32_t*)SYS_GPIO_0_DATA;
-
-	if (*pTim_stat & 1)
-	{
-		*pGPIO = led;
-		led = (led+1) % 64;
-
-		*pTim_stat = 1;	// Acknowledge IRQ
-		*pTim_ctrl |= 1;
-	}
-}
-
-void main()
-{
-	uint32_t i, j, k;
-	uint32_t data;
-	volatile uint32_t *pUART0_stat = (uint32_t*)SYS_UART_STAT;
-	volatile uint32_t *pGPIODIR = (uint32_t*)SYS_GPIO_0_DIR;
-	volatile uint32_t pSDRAM32[SDRAM_SIZE/4];
-	volatile uint16_t *pSDRAM16 = (uint16_t*)pSDRAM32;
-	volatile uint8_t *pSDRAM8 = (uint8_t*)pSDRAM32;
-	volatile uint32_t *pFlashMem = (uint32_t*)FLASH_BASE_MEM + 0x100000/4;
-
-	volatile uint32_t *pTim_ctrl = (uint32_t*)SYS_ITIM_CTRL;
-	volatile uint32_t *pTim_stat = (uint32_t*)SYS_ITIM_STAT;
-	volatile uint32_t *pTim0_cnt = (uint32_t*)SYS_ITIM0_CNT;
-	volatile uint32_t *pTim0_cmp = (uint32_t*)SYS_ITIM0_CMP;
-	volatile uint32_t *pSpiXferSize = (uint32_t*)SYS_SPI_XFER_SIZE;
-	volatile uint32_t *pSpiDataSize = (uint32_t*)SYS_SPI_DATA_SIZE;
-	volatile uint32_t *pSpiData = (uint32_t*)SYS_SPI_DATA;
-	volatile uint32_t *pSpiStat = (uint32_t*)SYS_SPI_STAT;
-	volatile uint32_t *pSpiCtrl = (uint32_t*)SYS_SPI_CTRL;
-	*pTim0_cnt = 0;
-	*pTim0_cmp = 2500000;	// 50 ms @ 50 Mhz
-	*pTim_stat = (1 << 0);
-	*pTim_ctrl = (3 << 0);
-	
-	uint32_t test_pattern [] = 
-	{
-		0x00000000,
-		0xFFFFFFFF,
-		0x55555555,
-		0xAAAAAAAA,
-		0x000000FF,
-		0x0000FF00,
-		0x00FF0000,
-		0xFF000000
-	};
-	
-	CP0_SR_write(0x0060000D);
-	*pGPIODIR = GPIO_0_DFLT_DIR;
-
-	interrupt_init();
-	interrupt_register(3, (void*)uart_isr);
-	interrupt_register(2, (void*)timer_isr);
-	interrupt_enable(2);
-	interrupt_enable(3);
-
-	// UART: enable RX interrupt
-	*pUART0_stat |= (1 << 6);
-
-	sputs("Hello, world!\n");
-
-	k = 0;
-	while(1)
-	{
-		sputs("Iteration # ");print_word(k);sputs("\n");
-#if 0
-		// SPI Bit rate
-		// fsys / (2*(1+div))
-		*pSpiCtrl       = (*pSpiCtrl & 0xFFFFFF00) | 0;
-
-		sputs("Test SPI\n");
-		*pSpiData		= 0x9F000000;
-		*pSpiDataSize	= 8;
-		*pSpiXferSize	= 8+648;
-		*pSpiStat		= SPI_STAT_COMMIT;
-
-		sputs("SYS_SPI_XFER_SIZE : ");print_word(*pSpiXferSize);sputs("\n");
-		sputs("SYS_SPI_DATA_SIZE : ");print_word(*pSpiDataSize);sputs("\n");
-		sputs("SYS_SPI_CTRL      : ");print_word(*pSpiCtrl);sputs("\n");
-		sputs("SYS_SPI_STAT      : ");print_word(*pSpiStat);sputs("\n");
-
-		while(!(*pSpiStat & SPI_STAT_DOUTRDY))
-		{
-		}
-		
-		do
-		{
-			print_word(*pSpiData);sputs("\n");
-		} while (*pSpiStat & SPI_STAT_DOUTRDY);
-		
-		sputs("SPI: Read at 0x100000\n");
-		*pSpiData		= 0x03100000;
-		*pSpiDataSize	= 32;
-		*pSpiXferSize	= 32+8*256;
-		*pSpiStat		= SPI_STAT_COMMIT;
-
-		while(!(*pSpiStat & SPI_STAT_DOUTRDY))
-		{
-		}
-		
-		do
-		{
-			print_word(*pSpiData);sputs("\n");
-		} while (*pSpiStat & SPI_STAT_DOUTRDY);
-
-#endif
-		
-		sputs("Testing SDRAM (pattern)\n");
-		for (j=0; j < ARRAY_SIZE(test_pattern); j++)
-		{
-			for (i=0; i < SDRAM_SIZE/4; i++)
-			{
-				pSDRAM32[i] = test_pattern[j];
-			}
-			DCACHE_invalidate_all();
-			for (i=0; i < SDRAM_SIZE/4; i++)
-			{
-				data = pSDRAM32[i];
-				if (data != test_pattern[j])
-				{
-					sputs("\n");
-					sputs("Pattern "); print_word(test_pattern[j]); sputs("\n");
-					sputs("Error at address "); print_word(i); sputs("\n");
-					sputs("Read "); print_word(data); sputs("\n");
-					break;
-				}
-			}
-			sputs(".");
-		}
-		sputs("\n");
-
-		sputs("Reading SPI Flash\n");
-		DCACHE_invalidate_all();
-		memdump((uint8_t*)pFlashMem, 0, 16, 512);
-		sputs("\n");
-		sputs("Size "); print_word(*(pFlashMem+3)); sputs("\n");
-		
-		sputs("Testing SDRAM (32-bit write)\n");
-		data = 0x00010203;
-		for (i=0; i < 256/4; i++)
-		{
-			pSDRAM32[i] = data;
-			data += 0x04040404;
-		}
-		DCACHE_invalidate_all();
-		memdump((uint8_t*)pSDRAM32, 0, 16, 256);
-		sputs("\n");
-
-		sputs("Testing SDRAM (16-bit write)\n");
-		data = 0x0001;
-		for (i=0; i < 256/2; i++)
-		{
-			pSDRAM16[i] = data;
-			data += 0x0202;
-		}
-		DCACHE_invalidate_all();
-		memdump((uint8_t*)pSDRAM16, 0, 16, 256);
-		sputs("\n");
-		
-		sputs("Testing SDRAM (8-bit write)\n");
-		data = 0x00;
-		for (i=0; i < 256; i++)
-		{
-			pSDRAM8[i] = data;
-			data += 0x01;
-		}
-		DCACHE_invalidate_all();
-		memdump((uint8_t*)pSDRAM8, 0, 16, 256);
-		sputs("\n");
-		
-		k++;
-	}
-}
-