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authorRob Herring (Arm) <robh@kernel.org>2026-08-31 14:43:51 -0500
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2026-09-13 18:17:31 -0700
commit55fc280e951ab2b39f3dcb640edc1b1eebc6d173 (patch)
treef0b5f37b42fc13b9908a31b657c646b024231cdd /scripts/Makefile.lib
downloadlinux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.tar.gz
linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.zip
Input: tsc2007 - read "ti,poll-period" as u32grafted
The "ti,poll-period" property is documented as a normal uint32 cell. The driver used a u64 helper, which makes the helper type disagree with the schema even though the stored value is still small. Read "ti,poll-period" with the u32 helper matching the documented DT cell size. Assisted-by: Codex:gpt-5-5 Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Link: https://patch.msgid.link/20260831194352.1185860-1-robh@kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'scripts/Makefile.lib')
-rw-r--r--scripts/Makefile.lib515
1 files changed, 515 insertions, 0 deletions
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
new file mode 100644
index 000000000..0a4fdd8bd
--- /dev/null
+++ b/scripts/Makefile.lib
@@ -0,0 +1,515 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# 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,$(modname)) \
+ -D__KBUILD_MODNAME=$(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%,, \
+ $(GCOV_PROFILE_$(target-stem).o)$(GCOV_PROFILE)$(if $(is-kernel-object),$(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%,, \
+ $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
+ $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
+_rust_flags += $(if $(patsubst n%,, \
+ $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
+ $(RUSTFLAGS_KASAN))
+endif
+endif
+
+ifeq ($(CONFIG_KMSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KMSAN_SANITIZE_$(target-stem).o)$(KMSAN_SANITIZE)$(is-kernel-object)), \
+ $(CFLAGS_KMSAN))
+_c_flags += $(if $(patsubst n%,, \
+ $(KMSAN_ENABLE_CHECKS_$(target-stem).o)$(KMSAN_ENABLE_CHECKS)$(is-kernel-object)), \
+ , -mllvm -msan-disable-checks=1)
+endif
+
+ifeq ($(CONFIG_UBSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SANITIZE)$(is-kernel-object)), \
+ $(CFLAGS_UBSAN))
+_c_flags += $(if $(patsubst n%,, \
+ $(UBSAN_INTEGER_WRAP_$(target-stem).o)$(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_INTEGER_WRAP)$(UBSAN_SANITIZE)$(is-kernel-object)), \
+ $(CFLAGS_UBSAN_INTEGER_WRAP))
+endif
+
+ifeq ($(CONFIG_KCOV),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KCOV_INSTRUMENT_$(target-stem).o)$(KCOV_INSTRUMENT)$(if $(is-kernel-object),$(CONFIG_KCOV_INSTRUMENT_ALL))), \
+ $(CFLAGS_KCOV))
+_rust_flags += $(if $(patsubst n%,, \
+ $(KCOV_INSTRUMENT_$(target-stem).o)$(KCOV_INSTRUMENT)$(if $(is-kernel-object),$(CONFIG_KCOV_INSTRUMENT_ALL))), \
+ $(RUSTFLAGS_KCOV))
+endif
+
+#
+# Enable KCSAN flags except some files or directories we don't want to check
+# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
+#
+ifeq ($(CONFIG_KCSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(KCSAN_SANITIZE_$(target-stem).o)$(KCSAN_SANITIZE)$(is-kernel-object)), \
+ $(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%,, \
+ $(KCSAN_INSTRUMENT_BARRIERS_$(target-stem).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \
+ -D__KCSAN_INSTRUMENT_BARRIERS__)
+endif
+
+#
+# Enable context analysis flags only where explicitly opted in.
+# (depends on variables CONTEXT_ANALYSIS_obj.o, CONTEXT_ANALYSIS)
+#
+ifeq ($(CONFIG_WARN_CONTEXT_ANALYSIS),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(CONTEXT_ANALYSIS_$(target-stem).o)$(CONTEXT_ANALYSIS)$(if $(is-kernel-object),$(CONFIG_WARN_CONTEXT_ANALYSIS_ALL))), \
+ $(CFLAGS_CONTEXT_ANALYSIS))
+endif
+
+#
+# Enable AutoFDO build flags except some files or directories we don't want to
+# enable (depends on variables AUTOFDO_PROFILE_obj.o and AUTOFDO_PROFILE).
+#
+ifeq ($(CONFIG_AUTOFDO_CLANG),y)
+_c_flags += $(if $(patsubst n%,, \
+ $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(is-kernel-object)), \
+ $(CFLAGS_AUTOFDO_CLANG))
+_rust_flags += $(if $(patsubst n%,, \
+ $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(is-kernel-object)), \
+ $(RUSTFLAGS_AUTOFDO_CLANG))
+endif
+
+#
+# Enable Propeller build flags except some files or directories we don't want to
+# enable (depends on variables AUTOFDO_PROPELLER_obj.o and PROPELLER_PROFILE).
+#
+ifdef CONFIG_PROPELLER_CLANG
+_c_flags += $(if $(patsubst n%,, \
+ $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(PROPELLER_PROFILE))$(is-kernel-object), \
+ $(CFLAGS_PROPELLER_CLANG))
+endif
+
+# $(src) for including checkin headers from generated source files
+# $(obj) for including generated headers from checkin source files
+ifdef building_out_of_srctree
+_c_flags += $(addprefix -I, $(src) $(obj))
+_a_flags += $(addprefix -I, $(src) $(obj))
+_cpp_flags += $(addprefix -I, $(src) $(obj))
+endif
+
+# If $(is-kernel-object) is 'y', this object will be linked to vmlinux or modules
+is-kernel-object = $(or $(part-of-builtin),$(part-of-module))
+
+part-of-builtin = $(if $(filter $(basename $@).o, $(real-obj-y) $(lib-y)),y)
+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) $(modfile_flags))
+
+c_flags = -Wp,-MMD,$(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) $(modname_flags)
+
+cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
+ $(_cpp_flags)
+
+ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
+
+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_MITIGATION_CALL_DEPTH_TRACKING) += --hacks=skylake
+objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt
+objtool-args-$(CONFIG_CALL_PADDING) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES)
+ifdef CONFIG_CALL_PADDING
+objtool-args-$(CONFIG_CFI) += --cfi
+objtool-args-$(CONFIG_FINEIBT) += --fineibt
+endif
+objtool-args-$(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-$(CONFIG_MITIGATION_RETPOLINE) += --retpoline
+objtool-args-$(CONFIG_MITIGATION_RETHUNK) += --rethunk
+objtool-args-$(CONFIG_MITIGATION_SLS) += --sls
+objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval
+objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call
+objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess
+objtool-args-$(or $(CONFIG_GCOV_KERNEL),$(CONFIG_KCOV)) += --no-unreachable
+objtool-args-$(CONFIG_OBJTOOL_WERROR) += --werror
+
+objtool-args = $(objtool-args-y) \
+ $(if $(delay-objtool), --link) \
+ $(if $(part-of-module), --module)
+
+delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT),$(CONFIG_KLP_BUILD))
+
+cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
+cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
+
+objtool-enabled := y
+
+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
+
+# Remove ".." and "." from a path, without using "realpath"
+# Usage:
+# $(call normalize_path,path/to/../file)
+define normalize_path
+$(strip $(eval elements :=) \
+$(foreach elem,$(subst /, ,$1), \
+ $(if $(filter-out .,$(elem)), \
+ $(if $(filter ..,$(elem)), \
+ $(eval elements := $(wordlist 2,$(words $(elements)),x $(elements))), \
+ $(eval elements := $(elements) $(elem))))) \
+$(subst $(space),/,$(elements)))
+endef
+
+# Build commands
+# ===========================================================================
+# These are shared by some Makefile.* files.
+
+ifdef CONFIG_LTO_CLANG
+# Run $(LD) here to convert LLVM IR to ELF in the following cases:
+# - when this object needs objtool processing, as objtool cannot process LLVM IR
+# - when this is a single-object module, as modpost cannot process LLVM IR
+cmd_ld_single = $(if $(objtool-enabled)$(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)
+endif
+
+ifdef CONFIG_LTO_CLANG_THIN_DIST
+# Save the _c_flags, sliently.
+quiet_cmd_save_c_flags =
+ saved_c_flags = $(_c_flags) $(modkern_cflags)
+ cmd_save_c_flags = printf '\n%s\n' 'saved_c_flags_$@ := $(call escsq,$(saved_c_flags))' >> $(dot-target).cmd
+endif
+
+quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
+ cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \
+ $(cmd_ld_single) \
+ $(cmd_objtool)
+
+define rule_cc_o_c
+ $(call cmd_and_fixdep,cc_o_c)
+ $(call cmd,save_c_flags)
+ $(call cmd,checksrc)
+ $(call cmd,checkdoc)
+ $(call cmd,gen_objtooldep)
+ $(call cmd,gen_symversions_c)
+ $(call cmd,record_mcount)
+ $(call cmd,warn_shared_object)
+endef
+
+quiet_cmd_as_o_S = AS $(quiet_modtag) $@
+ cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool)
+
+define rule_as_o_S
+ $(call cmd_and_fixdep,as_o_S)
+ $(call cmd,gen_objtooldep)
+ $(call cmd,gen_symversions_S)
+ $(call cmd,warn_shared_object)
+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)
+
+# Touch a file
+# ===========================================================================
+quiet_cmd_touch = TOUCH $(call normalize_path,$@)
+ cmd_touch = touch $@
+
+# 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 > $@
+
+# 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 -9 - - > $@
+
+quiet_cmd_lz4_with_size = LZ4 $@
+ cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -9 - -; \
+ $(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 $< $@
+
+# Flat Image Tree (FIT)
+# This allows for packaging of a kernel and all devicetrees files, using
+# compression.
+# ---------------------------------------------------------------------------
+
+MAKE_FIT := $(srctree)/scripts/make_fit.py
+
+# Use this to override the compression algorithm
+FIT_COMPRESSION ?= gzip
+
+quiet_cmd_fit = FIT $@
+ cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
+ --name '$(UIMAGE_NAME)' $(FIT_EXTRA_ARGS) \
+ $(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \
+ $(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \
+ --compress $(FIT_COMPRESSION) -k $< @$(word 2,$^)
+
+# XZ
+# ---------------------------------------------------------------------------
+# Use xzkern or xzkern_with_size 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_with_size 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