scripts/Makefile.lib

# SPDX-License-Identifier: GPL-2.0
# Backward compatibility
asflags-y  += $(EXTRA_AFLAGS)
ccflags-y  += $(EXTRA_CFLAGS)
cppflags-y += $(EXTRA_CPPFLAGS)
ldflags-y  += $(EXTRA_LDFLAGS)

#
# flags that take effect in sub directories
export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)
export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y)

# Figure out what we need to build from the various variables
# ===========================================================================

# When an object is listed to be built compiled-in and modular,
# only build the compiled-in version

obj-m := $(filter-out $(obj-y),$(obj-m))

# Libraries are always collected in one lib file.
# Filter out objects already built-in

lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))


# Handle objects in subdirs
# ---------------------------------------------------------------------------
# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o
#   and add the directory to the list of dirs to descend into: $(subdir-y)
# o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
#   and add the directory to the list of dirs to descend into: $(subdir-m)

# Determine modorder.
# Unfortunately, we don't have information about ordering between -y
# and -m subdirs.  Just put -y's first.
modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))

__subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
subdir-y	+= $(__subdir-y)
__subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
subdir-m	+= $(__subdir-m)
obj-y		:= $(patsubst %/, %/built-in.o, $(obj-y))
obj-m		:= $(filter-out %/, $(obj-m))

# Subdirectories we need to descend into

subdir-ym	:= $(sort $(subdir-y) $(subdir-m))

# if $(foo-objs) exists, foo.o is a composite object
multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
multi-used   := $(multi-used-y) $(multi-used-m)
single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m)))

# Build list of the parts of our composite objects, our composite
# objects depend on those (obviously)
multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y)))
multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y)))

# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
# tell kbuild to descend
subdir-obj-y := $(filter %/built-in.o, $(obj-y))

# Replace multi-part objects by their individual parts, look at local dir only
real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)
real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))

# Add subdir path

extra-y		:= $(addprefix $(obj)/,$(extra-y))
always		:= $(addprefix $(obj)/,$(always))
targets		:= $(addprefix $(obj)/,$(targets))
modorder	:= $(addprefix $(obj)/,$(modorder))
obj-y		:= $(addprefix $(obj)/,$(obj-y))
obj-m		:= $(addprefix $(obj)/,$(obj-m))
lib-y		:= $(addprefix $(obj)/,$(lib-y))
subdir-obj-y	:= $(addprefix $(obj)/,$(subdir-obj-y))
real-objs-y	:= $(addprefix $(obj)/,$(real-objs-y))
real-objs-m	:= $(addprefix $(obj)/,$(real-objs-m))
single-used-m	:= $(addprefix $(obj)/,$(single-used-m))
multi-used-y	:= $(addprefix $(obj)/,$(multi-used-y))
multi-used-m	:= $(addprefix $(obj)/,$(multi-used-m))
multi-objs-y	:= $(addprefix $(obj)/,$(multi-objs-y))
multi-objs-m	:= $(addprefix $(obj)/,$(multi-objs-m))
subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))

# These flags are needed for modversions and compiling, so we define them here
# already
# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will
# end up in (or would, if it gets compiled in)
# Note: Files that end up in two or more modules are compiled without the
#       KBUILD_MODNAME definition. The reason is that any made-up name would
#       differ in different configs.
name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote)
basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
modname_flags  = $(if $(filter 1,$(words $(modname))),\
                 -DKBUILD_MODNAME=$(call name-fix,$(modname)))

orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
                 $(ccflags-y) $(CFLAGS_$(basetarget).o)
_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \
                 $(asflags-y) $(AFLAGS_$(basetarget).o)
_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))
_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))

#
# Enable gcov profiling flags for a file, directory or for all files depending
# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
# (in this order)
#
ifeq ($(CONFIG_GCOV_KERNEL),y)
_c_flags += $(if $(patsubst n%,, \
		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
		$(CFLAGS_GCOV))
endif

#
# Enable address sanitizer flags for kernel except some files or directories
# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
#
ifeq ($(CONFIG_KASAN),y)
_c_flags += $(if $(patsubst n%,, \
		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
		$(CFLAGS_KASAN))
endif

# If building the kernel in a separate objtree expand all occurrences
# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').

ifeq ($(KBUILD_SRC),)
__c_flags	= $(_c_flags)
__a_flags	= $(_a_flags)
__cpp_flags     = $(_cpp_flags)
else

# -I$(obj) locates generated .h files
# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files
#   and locates generated .h files
# FIXME: Replace both with specific CFLAGS* statements in the makefiles
__c_flags	= $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \
		  $(call flags,_c_flags)
__a_flags	= $(call flags,_a_flags)
__cpp_flags     = $(call flags,_cpp_flags)
endif

# Modified for U-Boot: LINUXINCLUDE -> UBOOTINCLUDE
c_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(UBOOTINCLUDE)     \
		 $(__c_flags) $(modkern_cflags)                           \
		 $(basename_flags) $(modname_flags)

a_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(UBOOTINCLUDE)     \
		 $(__a_flags) $(modkern_aflags)

cpp_flags      = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(UBOOTINCLUDE)     \
		 $(__cpp_flags)

ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))

# Try these files in order to find the U-Boot-specific .dtsi include file
u_boot_dtsi_options = $(strip $(wildcard $(dir $<)$(basename $(notdir $<))-u-boot.dtsi) \
	$(wildcard $(dir $<)$(subst $\",,$(CONFIG_SYS_SOC))-u-boot.dtsi) \
	$(wildcard $(dir $<)$(subst $\",,$(CONFIG_SYS_CPU))-u-boot.dtsi) \
	$(wildcard $(dir $<)$(subst $\",,$(CONFIG_SYS_VENDOR))-u-boot.dtsi) \
	$(wildcard $(dir $<)u-boot.dtsi))

u_boot_dtsi_options_raw = $(warning Automatic .dtsi inclusion: options: \
	$(dir $<)$(basename $(notdir $<))-u-boot.dtsi \
	$(dir $<)$(subst $\",,$(CONFIG_SYS_SOC))-u-boot.dtsi \
	$(dir $<)$(subst $\",,$(CONFIG_SYS_CPU))-u-boot.dtsi \
	$(dir $<)$(subst $\",,$(CONFIG_SYS_VENDOR))-u-boot.dtsi \
	$(dir $<)u-boot.dtsi ... \
	found: $(if $(u_boot_dtsi_options),"$(u_boot_dtsi_options)",nothing!))

# Uncomment for debugging
# This shows all the files that were considered and the one that we chose.
# u_boot_dtsi_options_debug = $(u_boot_dtsi_options_raw)

# We use the first match
u_boot_dtsi = $(strip $(u_boot_dtsi_options_debug) \
	$(notdir $(firstword $(u_boot_dtsi_options))))

# Modified for U-Boot
dtc_cpp_flags  = -Wp,-MD,$(depfile).pre.tmp -nostdinc                    \
		 -I$(srctree)/arch/$(ARCH)/dts                           \
		 -I$(srctree)/arch/$(ARCH)/dts/include                   \
		 -Iinclude                                               \
		 -I$(srctree)/include                                    \
		 -I$(srctree)/arch/$(ARCH)/include                       \
		 -include $(srctree)/include/linux/kconfig.h             \
		 -D__ASSEMBLY__                                          \
		 -undef -D__DTS__

# Finds the multi-part object the current object will be linked into
modname-multi = $(sort $(foreach m,$(multi-used),\
		$(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))

# Useful for describing the dependency of composite objects
# Usage:
#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
define multi_depend
$(foreach m, $(notdir $1), \
	$(eval $(obj)/$m: \
	$(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
endef

# LEX
# ---------------------------------------------------------------------------
quiet_cmd_flex = LEX     $@
      cmd_flex = $(LEX) -o$@ -L $<

$(obj)/%.lex.c: $(src)/%.l FORCE
	$(call if_changed,flex)

# YACC
# ---------------------------------------------------------------------------
quiet_cmd_bison = YACC    $@
      cmd_bison = $(YACC) -o$@ -t -l $<

$(obj)/%.tab.c: $(src)/%.y FORCE
	$(call if_changed,bison)

quiet_cmd_bison_h = YACC    $@
      cmd_bison_h = $(YACC) -o/dev/null --defines=$@ -t -l $<

$(obj)/%.tab.h: $(src)/%.y FORCE
	$(call if_changed,bison_h)

# Shipped files
# ===========================================================================

quiet_cmd_shipped = SHIPPED $@
cmd_shipped = cat $< > $@

$(obj)/%: $(src)/%_shipped
	$(call cmd,shipped)

# Commands useful for building a boot image
# ===========================================================================
#
#	Use as following:
#
#	target: source(s) FORCE
#		$(if_changed,ld/objcopy/gzip)
#
#	and add target to extra-y so that we know we have to
#	read in the saved command line

# Linking
# ---------------------------------------------------------------------------

quiet_cmd_ld = LD      $@
cmd_ld = $(LD) $(ld_flags) $(filter-out FORCE,$^) -o $@

# Objcopy
# ---------------------------------------------------------------------------

quiet_cmd_objcopy = OBJCOPY $@
cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@

# Gzip
# ---------------------------------------------------------------------------

quiet_cmd_gzip = GZIP    $@
cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \
	(rm -f $@ ; false)

# DTC
# ---------------------------------------------------------------------------

# Disable noisy checks by default
ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
DTC_FLAGS += -Wno-unit_address_vs_reg \
	-Wno-unit_address_format \
	-Wno-avoid_unnecessary_addr_size \
	-Wno-alias_paths \
	-Wno-graph_child_address \
	-Wno-graph_port \
	-Wno-unique_unit_address \
	-Wno-simple_bus_reg \
	-Wno-pci_device_reg

# U-Boot specific disables
DTC_FLAGS += -Wno-pci_bridge \
        -Wno-pci_device_bus_num
endif

ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
DTC_FLAGS += -Wnode_name_chars_strict \
	-Wproperty_name_chars_strict
endif

DTC_FLAGS += $(DTC_FLAGS_$(basetarget))

# Generate an assembly file to wrap the output of the device tree compiler
quiet_cmd_dt_S_dtb= DTB     $@
# Modified for U-Boot
cmd_dt_S_dtb=						\
(							\
	echo '.section .dtb.init.rodata,"a"';		\
	echo '.balign 16';				\
	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
	echo '.incbin "$<" ';				\
	echo '__dtb_$(subst -,_,$(*F))_end:';		\
	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
	echo '.balign 16';				\
) > $@

$(obj)/%.dtb.S: $(obj)/%.dtb
	$(call cmd,dt_S_dtb)

ifeq ($(CONFIG_OF_LIBFDT_OVERLAY),y)
DTC_FLAGS += -@
endif

quiet_cmd_dtc = DTC     $@
# Modified for U-Boot
# Bring in any U-Boot-specific include at the end of the file
cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
	(cat $<; $(if $(u_boot_dtsi),echo '$(pound)include "$(u_boot_dtsi)"')) > $(pre-tmp); \
	$(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $(pre-tmp) ; \
	$(DTC) -O dtb -o $@ -b 0 \
		-i $(dir $<) $(DTC_FLAGS) \
		-d $(depfile).dtc.tmp $(dtc-tmp) || \
		(echo "Check $(shell pwd)/$(pre-tmp) for errors" && false) \
		; \
	sed "s:$(pre-tmp):$(<):" $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)

$(obj)/%.dtb: $(src)/%.dts FORCE
	$(call if_changed_dep,dtc)

pre-tmp = $(subst $(comma),_,$(dot-target).pre.tmp)
dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)

# DTCO
# ---------------------------------------------------------------------------

quiet_cmd_dtco = DTCO    $@
# Rule for objects only; does not put specific u-boot include at the end
# No generation of assembly file either
# Modified for U-Boot
cmd_dtco = mkdir -p $(dir ${dtc-tmp}) ; \
	$(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
	$(DTC) -@ -O dtb -o $@ -b 0 \
		-i $(dir $<) $(DTC_FLAGS) \
		-d $(depfile).dtc.tmp $(dtc-tmp) ; \
	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)

$(obj)/%.dtbo: $(src)/%.dts FORCE
	$(call if_changed_dep,dtco)

# Fonts
# ---------------------------------------------------------------------------

# Generate an assembly file to wrap the font data
quiet_cmd_S_ttf= TTF     $@
# Modified for U-Boot
cmd_S_ttf=						\
(							\
	echo '.section .rodata.ttf.init,"a"';		\
	echo '.balign 16';				\
	echo '.global __ttf_$(*F)_begin';		\
	echo '__ttf_$(*F)_begin:';			\
	echo '.incbin "$<" ';				\
	echo '__ttf_$(*F)_end:';			\
	echo '.global __ttf_$(*F)_end';			\
	echo '.balign 16';				\
) > $@

$(obj)/%.S: $(src)/%.ttf
	$(call cmd,S_ttf)

# EFI applications
# A Makefile target *.efi is built as EFI application.
# A Makefile target *_efi.S wraps *.efi as built-in EFI application.
# ---------------------------------------------------------------------------

# Generate an assembly file to wrap the EFI app
cmd_S_efi=					\
(						\
	echo '.section .rodata.$*.init,"a"';	\
	echo '.balign 16';			\
	echo '.global __efi_$*_begin';		\
	echo '__efi_$*_begin:';			\
	echo '.incbin "$<" ';			\
	echo '__efi_$*_end:';			\
	echo '.global __efi_$*_end';		\
	echo '.balign 16';			\
) > $@

$(obj)/%_efi.S: $(obj)/%.efi
	$(call cmd,S_efi)

quiet_cmd_efi_objcopy = OBJCOPY $@
cmd_efi_objcopy = $(OBJCOPY) -j .header -j .text -j .sdata -j .data -j \
		.dynamic -j .dynsym  -j .rel* -j .rela* -j .reloc \
		$(if $(EFI_TARGET),$(EFI_TARGET),-O binary) $^ $@

$(obj)/%.efi: $(obj)/%_efi.so
	$(call cmd,efi_objcopy)

quiet_cmd_efi_ld = LD      $@
cmd_efi_ld = $(LD) -nostdlib -znocombreloc -T $(EFI_LDS_PATH) -shared \
		-Bsymbolic -s $^ -o $@

EFI_LDS_PATH = $(srctree)/arch/$(ARCH)/lib/$(EFI_LDS)

$(obj)/efi_crt0.o: $(srctree)/arch/$(ARCH)/lib/$(EFI_CRT0:.o=.S) FORCE
	$(call if_changed_dep,as_o_S)

$(obj)/efi_reloc.o: $(srctree)/arch/$(ARCH)/lib/$(EFI_RELOC:.o=.c) $(recordmcount_source) FORCE
	$(call cmd,force_checksrc)
	$(call if_changed_rule,cc_o_c)

$(obj)/%_efi.so: $(obj)/%.o $(obj)/efi_crt0.o $(obj)/efi_reloc.o $(obj)/efi_freestanding.o
	$(call cmd,efi_ld)

targets += $(obj)/efi_crt0.o $(obj)/efi_reloc.o $(obj)/efi_freestanding.o

CFLAGS_REMOVE_efi_reloc.o := $(LTO_CFLAGS)
CFLAGS_REMOVE_efi_freestanding.o := $(LTO_CFLAGS)

# ACPI
# ---------------------------------------------------------------------------
#
# This first sends the file (typically dsdt.asl) through the preprocessor
# resolve includes and any CONFIG options used. This produces dsdt.asl.tmp
# which is pure ASL code. The Intel ASL (ACPI (Advanced Configuration and Power
# Interface) Source Language compiler (iasl) then converts this ASL code into a
# C file containing the hex data to build into U-Boot. This file is called
# dsdt.hex (despite us setting the prefix to .../dsdt.asl.tmp) so must be
# renamed to dsdt.c for consumption by the build system.
ASL_TMP = $(patsubst %.c,%.asl.tmp,$@)

quiet_cmd_acpi_c_asl= ASL     $<
cmd_acpi_c_asl=         \
	$(CPP) -x assembler-with-cpp -D__ASSEMBLY__ -D__ACPI__ \
		-P $(UBOOTINCLUDE) -o $(ASL_TMP) $< && \
	iasl -p $@ -tc $(ASL_TMP) $(if $(KBUILD_VERBOSE:1=), >/dev/null) && \
	mv $(patsubst %.c,%.hex,$@) $@

$(obj)/dsdt.c:    $(src)/dsdt.asl
	$(call cmd,acpi_c_asl)
	$(Q)sed -i -e "s,dsdt_aml_code,AmlCode," $@

# Bzip2
# ---------------------------------------------------------------------------

# Bzip2 and LZMA do not include size in file... so we have to fake that;
# append the size as a 32-bit littleendian number as gzip does.
size_append = printf $(shell						\
dec_size=0;								\
for F in $1; do								\
	fsize=$$(stat -c "%s" $$F);					\
	dec_size=$$(expr $$dec_size + $$fsize);				\
done;									\
printf "%08x\n" $$dec_size |						\
	sed 's/\(..\)/\1 /g' | {					\
		read ch0 ch1 ch2 ch3;					\
		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
			printf '%s%03o' '\\' $$((0x$$ch)); 		\
		done;							\
	}								\
)

quiet_cmd_bzip2 = BZIP2   $@
cmd_bzip2 = (cat $(filter-out FORCE,$^) | \
	bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
	(rm -f $@ ; false)

# Lzma
# ---------------------------------------------------------------------------

quiet_cmd_lzma = LZMA    $@
cmd_lzma = (cat $(filter-out FORCE,$^) | \
	lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
	(rm -f $@ ; false)

quiet_cmd_lzo = LZO     $@
cmd_lzo = (cat $(filter-out FORCE,$^) | \
	lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
	(rm -f $@ ; false)

quiet_cmd_lz4 = LZ4     $@
cmd_lz4 = (cat $(filter-out FORCE,$^) | \
	lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
	(rm -f $@ ; false)

# U-Boot mkimage
# ---------------------------------------------------------------------------

MKIMAGE := $(srctree)/scripts/mkuboot.sh

# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
# the number of overrides in arch makefiles
UIMAGE_ARCH ?= $(SRCARCH)
UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
UIMAGE_OPTS-y ?=
UIMAGE_TYPE ?= kernel
UIMAGE_LOADADDR ?= arch_must_set_this
UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
UIMAGE_IN ?= $<
UIMAGE_OUT ?= $@

quiet_cmd_uimage = UIMAGE  $(UIMAGE_OUT)
      cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
			-T $(UIMAGE_TYPE) \
			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
			-n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT)

# XZ
# ---------------------------------------------------------------------------
# Use xzkern to compress the kernel image and xzmisc to compress other things.
#
# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
# of the kernel decompressor. A BCJ filter is used if it is available for
# the target architecture. xzkern also appends uncompressed size of the data
# using size_append. The .xz format has the size information available at
# the end of the file too, but it's in more complex format and it's good to
# avoid changing the part of the boot code that reads the uncompressed size.
# Note that the bytes added by size_append will make the xz tool think that
# the file is corrupt. This is expected.
#
# xzmisc doesn't use size_append, so it can be used to create normal .xz
# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
# big dictionary would increase the memory usage too much in the multi-call
# decompression mode. A BCJ filter isn't used either.
quiet_cmd_xzkern = XZKERN  $@
cmd_xzkern = (cat $(filter-out FORCE,$^) | \
	sh $(srctree)/scripts/xz_wrap.sh && \
	$(call size_append, $(filter-out FORCE,$^))) > $@ || \
	(rm -f $@ ; false)

quiet_cmd_xzmisc = XZMISC  $@
cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
	xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
	(rm -f $@ ; false)

# Additional commands for U-Boot
#
# mkimage
# ---------------------------------------------------------------------------
MKIMAGEOUTPUT ?= /dev/null
quiet_cmd_mkimage = MKIMAGE $@
cmd_mkimage = $(objtree)/tools/mkimage $(MKIMAGEFLAGS_$(@F)) -d $< $@ \
	>$(MKIMAGEOUTPUT) $(if $(KBUILD_VERBOSE:0=), && cat $(MKIMAGEOUTPUT))

# fdtgrep
# ---------------------------------------------------------------------------
# Pass the original device tree file through fdtgrep twice. The first pass
# removes any unwanted nodes (i.e. those which don't have the
# 'u-boot,dm-pre-reloc' property and thus are not needed by SPL. The second
# pass removes various unused properties from the remaining nodes.
# The output is typically a much smaller device tree file.
ifeq ($(CONFIG_TPL_BUILD),y)
fdtgrep_props := -b u-boot,dm-pre-reloc -b u-boot,dm-tpl
else
fdtgrep_props := -b u-boot,dm-pre-reloc -b u-boot,dm-spl
endif
quiet_cmd_fdtgrep = FDTGREP $@
      cmd_fdtgrep = $(objtree)/tools/fdtgrep $(fdtgrep_props) -RT $< \
		-n /chosen -n /config -O dtb | \
	$(objtree)/tools/fdtgrep -r -O dtb - -o $@ \
		-P u-boot,dm-pre-reloc -P u-boot,dm-spl -P u-boot,dm-tpl \
		$(addprefix -P ,$(subst $\",,$(CONFIG_OF_SPL_REMOVE_PROPS)))

# fdt_rm_props
# ---------------------------------------------------------------------------
# Pass the original device tree file through fdtgrep. This removes various
# unused properties. The output is typically a smaller device tree file.
quiet_cmd_fdt_rm_props = FDTGREP $@
	cmd_fdt_rm_props = cat $< | $(objtree)/tools/fdtgrep -r -O dtb - -o $@ \
			$(addprefix -P ,$(subst $\",,$(CONFIG_OF_REMOVE_PROPS)))

# ASM offsets
# ---------------------------------------------------------------------------

# Default sed regexp - multiline due to syntax constraints
define sed-offsets
	"s:[[:space:]]*\.ascii[[:space:]]*\"\(.*\)\":\1:; \
	/^->/{s:->#\(.*\):/* \1 */:; \
	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
	s:->::; p;}"
endef

# Use filechk to avoid rebuilds when a header changes, but the resulting file
# does not
define filechk_offsets
	(set -e; \
	 echo "#ifndef $2"; \
	 echo "#define $2"; \
	 echo "/*"; \
	 echo " * DO NOT MODIFY."; \
	 echo " *"; \
	 echo " * This file was generated by Kbuild"; \
	 echo " */"; \
	 echo ""; \
	 sed -ne $(sed-offsets); \
	 echo ""; \
	 echo "#endif" )
endef