#
# Makefile for the LZMA compressed kernel loader for
# Realtek rtl819xx based boards
#
# Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
# Copyright (C) 2013 Roman Yeryomin <roman@advem.lv>
#
# Some parts of this file was based on the OpenWrt specific lzma-loader
# for the BCM47xx and ADM5120 based boards:
#	Copyright (C) 2004 Manuel Novoa III (mjn3@codepoet.org)
#	Copyright (C) 2005 Mineharu Takahara <mtakahar@yahoo.com>
#	Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 as published
# by the Free Software Foundation.
#

LOADADDR	:=
KERNELENTRY	:=
LZMA_TEXT_START	:= 0x80a00000
LOADER_DATA	:=
BOARD		:=
FLASH_OFFS	:=
FLASH_MAX	:=

CC		:= $(CROSS_COMPILE)gcc
LD		:= $(CROSS_COMPILE)ld
OBJCOPY		:= $(CROSS_COMPILE)objcopy
OBJDUMP		:= $(CROSS_COMPILE)objdump

BIN_FLAGS	:= -O binary -R .reginfo -R .note -R .comment -R .mdebug -S

CFLAGS		= -D__KERNEL__ -Wall -Wstrict-prototypes -Wno-trigraphs -Os \
		  -fno-strict-aliasing -fno-common -fomit-frame-pointer -G 0 \
		  -mno-abicalls -fno-pic -ffunction-sections -pipe -mlong-calls \
		  -fno-common -ffreestanding -fhonour-copts -mabi=32 -Wa,-32
CFLAGS		+= -D_LZMA_PROB32
CFLAGS		+= -I$(LINUX_DIR)/arch/rlx/include
CFLAGS		+= -I$(LINUX_DIR)/include/linux
CFLAGS		+= -I$(LINUX_DIR)/arch/rlx/bsp
CFLAGS		+= -I$(LINUX_DIR)/include
CFLAGS		+= -I$(LINUX_DIR)/arch/rlx/include/asm/mach-generic

ASFLAGS		= $(CFLAGS) -D__ASSEMBLY__

LDFLAGS		= -static --gc-sections -no-warn-mismatch
LDFLAGS		+= -e startup -T loader.lds -Ttext $(LZMA_TEXT_START)

O_FORMAT 	= $(shell $(OBJDUMP) -i | head -2 | grep elf32)

OBJECTS		:= head.o loader.o cache.o board.o printf.o LzmaDecode.o

# Realtek chips have different march'es, e.g. rlx4181 and rlx5281
ifneq ($(strip $(MARCH)),)
CFLAGS		+= -Wa,-march=$(MARCH) -march=$(MARCH)
else
CFLAGS		+= -Wa,-march=rlx4181 -march=rlx4181
endif

# hacky way to get/define real kernel_entry address
# see image/Makefile and loader.c for details
ifneq ($(strip $(KERNELENTRY)),)
CFLAGS		+= -DKERNELENTRY=$(KERNELENTRY)
endif

ifneq ($(strip $(LOADER_DATA)),)
OBJECTS		+= data.o
CFLAGS		+= -DLZMA_WRAPPER=1 -DLOADADDR=$(LOADADDR)
endif

ifneq ($(strip $(KERNEL_CMDLINE)),)
CFLAGS		+= -DCONFIG_KERNEL_CMDLINE='"$(KERNEL_CMDLINE)"'
endif

ifneq ($(strip $(FLASH_OFFS)),)
CFLAGS		+= -DCONFIG_FLASH_OFFS=$(FLASH_OFFS)
endif

ifneq ($(strip $(FLASH_MAX)),)
CFLAGS		+= -DCONFIG_FLASH_MAX=$(FLASH_MAX)
endif

BOARD_DEF := $(shell echo $(strip $(BOARD)) | tr a-z A-Z | tr - _)
ifneq ($(BOARD_DEF),)
CFLAGS		+= -DCONFIG_BOARD_$(BOARD_DEF)
endif

all: loader.bin

# Don't build dependencies, this may die if $(CC) isn't gcc
dep:

install:

%.o : %.c
	$(CC) $(CFLAGS) -c -o $@ $<

%.o : %.S
	$(CC) $(ASFLAGS) -c -o $@ $<

data.o: $(LOADER_DATA)
	$(LD) -r -b binary --oformat $(O_FORMAT) -T lzma-data.lds -o $@ $<

loader.bin: loader.elf
	$(OBJCOPY) $(BIN_FLAGS) $< $@

loader.elf: $(OBJECTS)
	$(LD) $(LDFLAGS) -o $@ $(OBJECTS)

mrproper: clean

clean:
	rm -f *.elf *.bin *.o