#############################################################
#
# Linux kernel targets
#
# Note:  If you have any patches to apply, create the directory
# sources/kernel-patches and put your patches in there and number
# them in the order you wish to apply them...  i.e.
#
#   patches/kernel/001-my-special-stuff.bz2
#   patches/kernel/003-gcc-Os.bz2
#   patches/kernel/004_no-warnings.bz2
#   patches/kernel/030-lowlatency-mini.bz2
#   patches/kernel/031-lowlatency-fixes-5.bz2
#   patches/kernel/099-shutup.bz2
#   etc...
#
# these patches will all be applied by the patch-kernel.sh
# script (which will also abort the build if it finds rejects)
#  -Erik
#
# It will also do patch-o-matic patches, dependant on the patch-o-matic
# TARGET and the POM_PATCHES list in the main Makefile.
#
# -Thomas.
#
#############################################################

# Version of Linux to download and then apply patches to
DOWNLOAD_LINUX_VERSION=2.4.37.11
# Version of Linux AFTER patches
LINUX_VERSION=$(DOWNLOAD_LINUX_VERSION)-floppyfw-$(FLOPPYFW_VERSION)

LINUX_FORMAT=bzImage
LINUX_BINLOC=arch/$(ARCH)/boot/$(LINUX_FORMAT)

LINUX_DIR=$(BUILD_DIR)/linux-$(LINUX_VERSION)
LINUX_SOURCE=linux-$(DOWNLOAD_LINUX_VERSION).tar.bz2
# LINUX_SITE=ftp://ftp.kernel.org/pub/linux/kernel/v2.4
LINUX_SITE=http://www.zelow.no/floppyfw/download/hosted_source_packages/
LINUX_KCONFIG=$(CONFIG_DIR)/config-kernel
LINUX_KERNEL=$(LINUX_DIR)/vmlinuz
# Used by pcmcia-cs and others
LINUX_SOURCE_DIR=$(LINUX_DIR)

LINUX_MODULES_DEP=$(MODULES_DIR)/lib/modules/$(LINUX_VERSION)/modules.dep

UPX=upx-1.11
#LINUX_CC_OPTS="-Os -pipe"
# LINUX_CC_OPTS="-Os -mregparm=3 -falign-functions=2 -falign-jumps=2 -falign-labels=2 -falign-loops=2"
#LINUX_CC_OPTS="-Os -funit-at-a-time  -mregparm=3 -Wall -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -fomit-frame-pointer -pipe -mpreferred-stack-boundary=2 -march=$(ARCH) -nostdinc -iwithprefix"

$(DL_DIR)/$(LINUX_SOURCE): 
	 $(WGET) -P $(DL_DIR) $(LINUX_SITE)/$(LINUX_SOURCE)

$(LINUX_DIR)/.unpacked: $(DL_DIR)/$(LINUX_SOURCE) 
	-$(RM) -r $(MODULES_DIR)/lib
	-$(RM) $(MODULES_DIR)/.stripped
	-$(RM) -r $(LINUX_DIR)
	bzcat $(DL_DIR)/$(LINUX_SOURCE) | tar $(TAR_VERBOSE) \
		-C $(BUILD_DIR) -xf -
ifneq ($(DOWNLOAD_LINUX_VERSION),$(LINUX_VERSION))
	# Rename the dir from the downloaded version to the AFTER patch version	
	mv -f $(BUILD_DIR)/linux-$(DOWNLOAD_LINUX_VERSION) $(LINUX_DIR)
	touch $(LINUX_DIR)/.unpacked
endif

$(LINUX_DIR)/.patched: $(LINUX_DIR)/.unpacked
	mkdir -p $(PATCH_DIR)/kernel
	# Patching the kernel.
	$(PATCH_DIR)/patch-kernel.sh $(LINUX_DIR) $(PATCH_DIR)/kernel 0*
	echo "Patched the kernel with $(PATCH_DIR)/kernel patches"

	# Patching the kernel with iptables-pom-stuff:
ifeq ($(filter $(TARGETS),patch-o-matic), patch-o-matic)
	(cd $(PATCH_O_MATIC_DIR); \
		KERNEL_DIR=$(LINUX_DIR) \
		IPTABLES_DIR=$(IPTABLES_BUILD_DIR) \
		./runme	--batch $(POM_PATCHES) \
		 );
endif
ifeq ($(filter $(TARGETS),hostap), hostap)
	(cd $(LINUX_DIR); \
	cat $(HOSTAP_DRIVER_KERNEL_PATCH) | patch -p1 ; \
	cp $(HOSTAP_DRIVER_DIR)/driver/modules/hostap*.[ch] \
		drivers/net/wireless/. );
endif

	# Postpatching the kernel after iptables-pom-stuff because of the
	# troublesome CONFIG_IP_NF_MATCH_OWNER option.
	$(PATCH_DIR)/patch-kernel.sh $(LINUX_DIR) \
		$(PATCH_DIR)/kernel-after-pom 0*

	# From a lwn article: need gcc 3.4/3.5, 
	# It segfaults with it.. 
	#  -funit-at-a-time  -mregparm=3
	# From a patch by Eric Anderson: (But these don't reduce size, weird)
	#  -falign-functions=2 -falign-jumps=2 -falign-labels=2 -falign-loops=2
	# From: http://www.ussg.iu.edu/hypermail/linux/kernel/0501.2/0856.html
	#  -mpreferred-stack-boundary=2 -malign-loops=0 -malign-jumps=0 -malign-functions=0
	#  But: -malign-loops is obsolete, use -falign-loops
	#  -malign-jumps is obsolete, use -falign-jumps
	#  -malign-functions is obsolete, use -falign-functions
	#  And they don't make a smaller kernel than pure -Os anyway.
	$(SED) 's/\-O2/-Os -pipe/;' $(LINUX_DIR)/Makefile
	-(cd $(BUILD_DIR); ln -sf $(LINUX_DIR) linux)
	touch $(LINUX_DIR)/.patched

$(LINUX_KCONFIG):
	@if [ ! -f "$(LINUX_KCONFIG)" ] ; then \
		echo ""; \
		echo "You should create a .config for your kernel"; \
		echo "and install it as $(LINUX_KCONFIG)"; \
		echo ""; \
		sleep 5; \
	fi;


$(LINUX_DIR)/.configured:  $(LINUX_DIR)/.patched  $(LINUX_KCONFIG)
	-cp $(LINUX_KCONFIG) $(LINUX_DIR)/.config
ifeq ($(strip $(EMULATE_FPU)),true)
	$(SED) "s/^.*CONFIG_MATH_EMULATION.*/CONFIG_MATH_EMULATION=y/;" \
		$(LINUX_DIR)/.config
else
	$(SED) "s/^.*CONFIG_MATH_EMULATION.*/CONFIG_MATH_EMULATION=n/;" \
		$(LINUX_DIR)/.config
endif

# It's default on now.
#ifeq ($(filter $(TARGETS),madwifi), madwifi)
#	$(SED) "s/^.*CONFIG_CRYPTO.*/CONFIG_CRYPTO=y/;" \
#		$(LINUX_DIR)/.config
#endif

	$(SED) 's/^EXTRAVERSION\s=\s(.*)/EXTRAVERSION = $$1-floppyfw-$(FLOPPYFW_VERSION)/;' \
		$(LINUX_DIR)/Makefile
	$(MAKE) D=1 V=1 ARCH=$(ARCH) -C $(LINUX_DIR) oldconfig include/linux/version.h
	# Annoying but hopefully this is enough:
	# And I'm using perl as sed...
	$(SED) 's/CONFIG_X86_64.*//' $(LINUX_DIR)/.config
	touch $(LINUX_DIR)/.configured

linux-source-configured: $(LINUX_DIR)/.configured

$(LINUX_DIR)/.depend_done: $(LINUX_DIR)/.configured
	$(MAKE) D=1 V=1 ARCH=$(ARCH) -C $(LINUX_DIR) dep
	touch $(LINUX_DIR)/.depend_done

$(LINUX_DIR)/$(LINUX_BINLOC): $(LINUX_DIR)/.depend_done
	$(MAKE) D=1 V=1 ARCH=$(ARCH) CC="$(TARGET_CC)" -C $(LINUX_DIR) $(LINUX_FORMAT)
	$(MAKE) D=1 V=1 ARCH=$(ARCH) CC="$(TARGET_CC)" -C $(LINUX_DIR) modules

$(LINUX_MODULES_DEP): $(LINUX_DIR)/.depend_done
	$(RM) -r $(MODULES_DIR)/lib/modules
	$(MAKE) D=1 V=1 ARCH=$(ARCH) -C $(LINUX_DIR) INSTALL_MOD_PATH=$(MODULES_DIR) modules_install

	[ -d $(MODULES_DIR)/lib/modules/$(LINUX_VERSION) ] && \
	$(BASE_DIR)/perl/depmod.pl -n \
		-b $(MODULES_DIR)/lib/modules/$(LINUX_VERSION)/ \
		-k $(LINUX_DIR)/vmlinux \
		> $(LINUX_MODULES_DEP)

	(cd $(MODULES_BASE_DIR) ; cat $(LINUX_MODULES_DEP) | $(BASE_DIR)/perl/capsfix.pl > $(TMP_DIR)/moddep )

	cp $(LINUX_MODULES_DEP) $(LINUX_MODULES_DEP).precaps

	cp $(TMP_DIR)/moddep $(LINUX_MODULES_DEP)

	(cd $(MODULES_DIR)/lib/modules; ln -s $(LINUX_VERSION)/kernel/drivers .)
	# $(DEPMOD)

$(LINUX_KERNEL): $(LINUX_DIR)/$(LINUX_BINLOC)
	cp -fa $(LINUX_DIR)/$(LINUX_BINLOC) $(LINUX_KERNEL)
	# cp -fa $(LINUX_DIR)/$(LINUX_BINLOC) $(LINUX_KERNEL).upx
	# $(UPX) -9 $(LINUX_KERNEL).upx
	touch -c $(LINUX_KERNEL)


linux:  patch-o-matic hostap-driver-source $(IPTABLES_BUILD_DIR)/.configured $(LINUX_KERNEL) $(LINUX_MODULES_DEP)

linux-depmod: linux
	# Modutils-version
	#/sbin/depmod -aen -F $(LINUX_DIR)/System.map -b $(MODULES_DIR)/lib/modules/$(LINUX_VERSION) > $(LINUX_MODULES_DEP)

	[ -f $(LINUX_MODULES_DEP) ] && \
		cp $(LINUX_MODULES_DEP) $(LINUX_MODULES_DEP).precaps

	# busybox perl.
	[ -d $(MODULES_DIR)/lib/modules/$(LINUX_VERSION) ] && \
	$(BASE_DIR)/perl/depmod.pl -n \
		-b $(MODULES_DIR)/lib/modules/$(LINUX_VERSION)/ \
		-k $(LINUX_DIR)/vmlinux \
		> $(LINUX_MODULES_DEP)

	# "Sanitizing" it.
	$(SED) 's/\\\n//' $(LINUX_MODULES_DEP)

linux-source: $(DL_DIR)/$(LINUX_SOURCE)

# This has been renamed so we do _NOT_ by default run this on 'make clean'
linuxclean: clean
	$(RM) $(LINUX_KERNEL)
	-$(MAKE) ARCH=$(ARCH) -C $(LINUX_DIR) clean

linux-dirclean:
	$(RM) -r $(LINUX_DIR)