summaryrefslogtreecommitdiffstats
path: root/scripts/Makefile.lib
diff options
context:
space:
mode:
Diffstat (limited to 'scripts/Makefile.lib')
-rw-r--r--scripts/Makefile.lib579
1 files changed, 579 insertions, 0 deletions
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
new file mode 100644
index 0000000000..68d0134bdb
--- /dev/null
+++ b/scripts/Makefile.lib
@@ -0,0 +1,579 @@
+# 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 current and sub directories
+KBUILD_AFLAGS += $(subdir-asflags-y)
+KBUILD_CFLAGS += $(subdir-ccflags-y)
+KBUILD_RUSTFLAGS += $(subdir-rustflags-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)))
+
+# Subdirectories we need to descend into
+subdir-ym := $(sort $(subdir-y) $(subdir-m) \
+ $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
+
+# Handle objects in subdirs:
+# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
+# foo/modules.order
+# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
+#
+# Generate modules.order to determine modorder. Unfortunately, we don't have
+# information about ordering between -y and -m subdirs. Just put -y's first.
+
+ifdef need-modorder
+obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
+else
+obj-m := $(filter-out %/, $(obj-m))
+endif
+
+ifdef need-builtin
+obj-y := $(patsubst %/, %/built-in.a, $(obj-y))
+else
+obj-y := $(filter-out %/, $(obj-y))
+endif
+
+# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
+suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
+# List composite targets that are constructed by combining other targets
+multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
+# List primitive targets that are compiled from source files
+real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
+
+# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
+multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
+multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
+multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
+
+# Replace multi-part objects by their individual parts,
+# including built-in.a from subdirectories
+real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
+real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
+
+always-y += $(always-m)
+
+# hostprogs-always-y += foo
+# ... is a shorthand for
+# hostprogs += foo
+# always-y += foo
+hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
+always-y += $(hostprogs-always-y) $(hostprogs-always-m)
+
+# userprogs-always-y is likewise.
+userprogs += $(userprogs-always-y) $(userprogs-always-m)
+always-y += $(userprogs-always-y) $(userprogs-always-m)
+
+# DTB
+# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
+dtb-$(CONFIG_OF_ALL_DTBS) += $(dtb-)
+
+# Composite DTB (i.e. DTB constructed by overlay)
+multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs)
+# Primitive DTB compiled from *.dts
+real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs)
+# Base DTB that overlay is applied onto (each first word of $(*-dtbs) expansion)
+base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m, .dtb, -dtbs)))
+
+always-y += $(dtb-y)
+
+# Add subdir path
+
+ifneq ($(obj),.)
+extra-y := $(addprefix $(obj)/,$(extra-y))
+always-y := $(addprefix $(obj)/,$(always-y))
+targets := $(addprefix $(obj)/,$(targets))
+obj-m := $(addprefix $(obj)/,$(obj-m))
+lib-y := $(addprefix $(obj)/,$(lib-y))
+real-obj-y := $(addprefix $(obj)/,$(real-obj-y))
+real-obj-m := $(addprefix $(obj)/,$(real-obj-m))
+multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m))
+multi-dtb-y := $(addprefix $(obj)/, $(multi-dtb-y))
+real-dtb-y := $(addprefix $(obj)/, $(real-dtb-y))
+subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
+endif
+
+# Finds the multi-part object the current object will be linked into.
+# If the object belongs to two or more multi-part objects, list them all.
+modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
+ $(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
+
+__modname = $(or $(modname-multi),$(basetarget))
+
+modname = $(subst $(space),:,$(__modname))
+modfile = $(addprefix $(obj)/,$(__modname))
+
+# target with $(obj)/ and its suffix stripped
+target-stem = $(basename $(patsubst $(obj)/%,%,$@))
+
+# These flags are needed for modversions and compiling, so we define them here
+# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
+# end up in (or would, if it gets compiled in)
+name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
+name-fix = $(call stringify,$(call name-fix-token,$1))
+basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
+modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
+ -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
+modfile_flags = -DKBUILD_MODFILE=$(call stringify,$(modfile))
+
+_c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
+ $(filter-out $(ccflags-remove-y), \
+ $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
+ $(CFLAGS_$(target-stem).o))
+_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \
+ $(filter-out $(rustflags-remove-y), \
+ $(KBUILD_RUSTFLAGS) $(rustflags-y)) \
+ $(RUSTFLAGS_$(target-stem).o))
+_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
+ $(filter-out $(asflags-remove-y), \
+ $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
+ $(AFLAGS_$(target-stem).o))
+_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
+
+#
+# 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)
+ifneq ($(CONFIG_KASAN_HW_TAGS),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
+ $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
+endif
+endif
+
+ifeq ($(CONFIG_KMSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KMSAN_SANITIZE_$(basetarget).o)$(KMSAN_SANITIZE)y), \
+ $(CFLAGS_KMSAN))
+_c_flags += $(if $(patsubst n%,, \
+ $(KMSAN_ENABLE_CHECKS_$(basetarget).o)$(KMSAN_ENABLE_CHECKS)y), \
+ , -mllvm -msan-disable-checks=1)
+endif
+
+ifeq ($(CONFIG_UBSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
+ $(CFLAGS_UBSAN))
+endif
+
+ifeq ($(CONFIG_KCOV),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
+ $(CFLAGS_KCOV))
+endif
+
+#
+# Enable KCSAN flags except some files or directories we don't want to check
+# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
+#
+ifeq ($(CONFIG_KCSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \
+ $(CFLAGS_KCSAN))
+# Some uninstrumented files provide implied barriers required to avoid false
+# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only.
+_c_flags += $(if $(patsubst n%,, \
+ $(KCSAN_INSTRUMENT_BARRIERS_$(basetarget).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \
+ -D__KCSAN_INSTRUMENT_BARRIERS__)
+endif
+
+# $(srctree)/$(src) for including checkin headers from generated source files
+# $(objtree)/$(obj) for including generated headers from checkin source files
+ifeq ($(KBUILD_EXTMOD),)
+ifdef building_out_of_srctree
+_c_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
+_a_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
+_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
+endif
+endif
+
+part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
+quiet_modtag = $(if $(part-of-module),[M], )
+
+modkern_cflags = \
+ $(if $(part-of-module), \
+ $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
+ $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
+
+modkern_rustflags = \
+ $(if $(part-of-module), \
+ $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \
+ $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL))
+
+modkern_aflags = $(if $(part-of-module), \
+ $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \
+ $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
+
+c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
+ -include $(srctree)/include/linux/compiler_types.h \
+ $(_c_flags) $(modkern_cflags) \
+ $(basename_flags) $(modname_flags)
+
+rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg
+
+a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
+ $(_a_flags) $(modkern_aflags)
+
+cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
+ $(_cpp_flags)
+
+ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
+
+DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes
+
+dtc_cpp_flags = -Wp,-MMD,$(depfile).pre.tmp -nostdinc \
+ $(addprefix -I,$(DTC_INCLUDE)) \
+ -undef -D__DTS__
+
+ifdef CONFIG_OBJTOOL
+
+objtool := $(objtree)/tools/objtool/objtool
+
+objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) += --hacks=jump_label
+objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) += --hacks=noinstr
+objtool-args-$(CONFIG_CALL_DEPTH_TRACKING) += --hacks=skylake
+objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt
+objtool-args-$(CONFIG_FINEIBT) += --cfi
+objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL) += --mcount
+ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
+objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT) += --mnop
+endif
+objtool-args-$(CONFIG_UNWINDER_ORC) += --orc
+objtool-args-$(CONFIG_RETPOLINE) += --retpoline
+objtool-args-$(CONFIG_RETHUNK) += --rethunk
+objtool-args-$(CONFIG_SLS) += --sls
+objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval
+objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call
+objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess
+objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable
+objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES)
+
+objtool-args = $(objtool-args-y) \
+ $(if $(delay-objtool), --link) \
+ $(if $(part-of-module), --module)
+
+delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
+
+cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
+cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
+
+endif # CONFIG_OBJTOOL
+
+# 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, $1, \
+ $(eval $m: \
+ $(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3))))
+endef
+
+# Copy a file
+# ===========================================================================
+# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
+# the copy would be read-only as well, leading to an error when executing the
+# rule next time. Use 'cat' instead in order to generate a writable file.
+quiet_cmd_copy = COPY $@
+ cmd_copy = cat $< > $@
+
+$(obj)/%: $(src)/%_shipped
+ $(call cmd,copy)
+
+# Commands useful for building a boot image
+# ===========================================================================
+#
+# Use as following:
+#
+# target: source(s) FORCE
+# $(if_changed,ld/objcopy/gzip)
+#
+# and add target to 'targets' so that we know we have to
+# read in the saved command line
+
+# Linking
+# ---------------------------------------------------------------------------
+
+quiet_cmd_ld = LD $@
+ cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
+
+# Archive
+# ---------------------------------------------------------------------------
+
+quiet_cmd_ar = AR $@
+ cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
+
+# Objcopy
+# ---------------------------------------------------------------------------
+
+quiet_cmd_objcopy = OBJCOPY $@
+cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
+
+# Gzip
+# ---------------------------------------------------------------------------
+
+quiet_cmd_gzip = GZIP $@
+ cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
+
+# DTC
+# ---------------------------------------------------------------------------
+DTC ?= $(objtree)/scripts/dtc/dtc
+DTC_FLAGS += -Wno-interrupt_provider \
+ -Wno-unique_unit_address
+
+# Disable noisy checks by default
+ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
+DTC_FLAGS += -Wno-unit_address_vs_reg \
+ -Wno-avoid_unnecessary_addr_size \
+ -Wno-alias_paths \
+ -Wno-graph_child_address \
+ -Wno-simple_bus_reg
+else
+DTC_FLAGS += \
+ -Wunique_unit_address_if_enabled
+endif
+
+ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
+DTC_FLAGS += -Wnode_name_chars_strict \
+ -Wproperty_name_chars_strict \
+ -Winterrupt_provider \
+ -Wunique_unit_address
+endif
+
+DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
+
+# Set -@ if the target is a base DTB that overlay is applied onto
+DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
+
+# Generate an assembly file to wrap the output of the device tree compiler
+quiet_cmd_wrap_S_dtb = WRAP $@
+ cmd_wrap_S_dtb = { \
+ symbase=__$(patsubst .%,%,$(suffix $<))_$(subst -,_,$(notdir $*)); \
+ echo '\#include <asm-generic/vmlinux.lds.h>'; \
+ echo '.section .dtb.init.rodata,"a"'; \
+ echo '.balign STRUCT_ALIGNMENT'; \
+ echo ".global $${symbase}_begin"; \
+ echo "$${symbase}_begin:"; \
+ echo '.incbin "$<" '; \
+ echo ".global $${symbase}_end"; \
+ echo "$${symbase}_end:"; \
+ echo '.balign STRUCT_ALIGNMENT'; \
+ } > $@
+
+$(obj)/%.dtb.S: $(obj)/%.dtb FORCE
+ $(call if_changed,wrap_S_dtb)
+
+$(obj)/%.dtbo.S: $(obj)/%.dtbo FORCE
+ $(call if_changed,wrap_S_dtb)
+
+quiet_cmd_dtc = DTC $@
+cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
+ $(DTC) -o $@ -b 0 \
+ $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
+ -d $(depfile).dtc.tmp $(dtc-tmp) ; \
+ cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
+
+quiet_cmd_fdtoverlay = DTOVL $@
+ cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
+
+$(multi-dtb-y): FORCE
+ $(call if_changed,fdtoverlay)
+$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
+
+ifneq ($(CHECK_DTBS)$(CHECK_DT_BINDING),)
+DT_CHECKER ?= dt-validate
+DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),-l $(DT_SCHEMA_FILES),-m)
+DT_BINDING_DIR := Documentation/devicetree/bindings
+DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
+
+quiet_cmd_dtb = DTC_CHK $@
+ cmd_dtb = $(cmd_dtc) ; $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true
+else
+quiet_cmd_dtb = $(quiet_cmd_dtc)
+ cmd_dtb = $(cmd_dtc)
+endif
+
+$(obj)/%.dtb: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
+ $(call if_changed_dep,dtb)
+
+$(obj)/%.dtbo: $(src)/%.dtso $(DTC) FORCE
+ $(call if_changed_dep,dtc)
+
+dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
+
+# Bzip2
+# ---------------------------------------------------------------------------
+
+# Bzip2 and LZMA do not include size in file... so we have to fake that;
+# append the size as a 32-bit littleendian number as gzip does.
+size_append = printf $(shell \
+dec_size=0; \
+for F in $(real-prereqs); do \
+ fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \
+ dec_size=$$(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_file_size = GEN $@
+ cmd_file_size = $(size_append) > $@
+
+quiet_cmd_bzip2 = BZIP2 $@
+ cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@
+
+quiet_cmd_bzip2_with_size = BZIP2 $@
+ cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
+
+# Lzma
+# ---------------------------------------------------------------------------
+
+quiet_cmd_lzma = LZMA $@
+ cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@
+
+quiet_cmd_lzma_with_size = LZMA $@
+ cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
+
+quiet_cmd_lzo = LZO $@
+ cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@
+
+quiet_cmd_lzo_with_size = LZO $@
+ cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
+
+quiet_cmd_lz4 = LZ4 $@
+ cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout > $@
+
+quiet_cmd_lz4_with_size = LZ4 $@
+ cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout; \
+ $(size_append); } > $@
+
+# 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 ?= $(or $(2),none)
+UIMAGE_OPTS-y ?=
+UIMAGE_TYPE ?= kernel
+UIMAGE_LOADADDR ?= arch_must_set_this
+UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
+UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
+
+quiet_cmd_uimage = UIMAGE $@
+ cmd_uimage = $(BASH) $(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 $< $@
+
+# 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 $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@
+
+quiet_cmd_xzkern_with_size = XZKERN $@
+ cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
+ $(size_append); } > $@
+
+quiet_cmd_xzmisc = XZMISC $@
+ cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
+
+# ZSTD
+# ---------------------------------------------------------------------------
+# Appends the uncompressed size of the data using size_append. The .zst
+# format has the size information available at the beginning of the file too,
+# but it's in a 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 zstd tool think that
+# the file is corrupt. This is expected.
+#
+# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
+# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
+# single pass, so zstd doesn't need to allocate a window buffer. When streaming
+# decompression is used, like initramfs decompression, zstd22 should likely not
+# be used because it would require zstd to allocate a 128 MB buffer.
+
+quiet_cmd_zstd = ZSTD $@
+ cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@
+
+quiet_cmd_zstd22 = ZSTD22 $@
+ cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@
+
+quiet_cmd_zstd22_with_size = ZSTD22 $@
+ cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
+
+# ASM offsets
+# ---------------------------------------------------------------------------
+
+# Default sed regexp - multiline due to syntax constraints
+#
+# Use [:space:] because LLVM's integrated assembler inserts <tab> around
+# the .ascii directive whereas GCC keeps the <space> as-is.
+define sed-offsets
+ 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
+ /^->/{s:->#\(.*\):/* \1 */:; \
+ 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
+ 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