xref: /linux/scripts/Makefile.lib (revision f80be4571b19b9fd8dd1528cd2a2f123aff51f70)
1# SPDX-License-Identifier: GPL-2.0
2# Backward compatibility
3asflags-y  += $(EXTRA_AFLAGS)
4ccflags-y  += $(EXTRA_CFLAGS)
5cppflags-y += $(EXTRA_CPPFLAGS)
6ldflags-y  += $(EXTRA_LDFLAGS)
7
8# flags that take effect in current and sub directories
9KBUILD_AFLAGS += $(subdir-asflags-y)
10KBUILD_CFLAGS += $(subdir-ccflags-y)
11
12# Figure out what we need to build from the various variables
13# ===========================================================================
14
15# When an object is listed to be built compiled-in and modular,
16# only build the compiled-in version
17obj-m := $(filter-out $(obj-y),$(obj-m))
18
19# Libraries are always collected in one lib file.
20# Filter out objects already built-in
21lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
22
23# Subdirectories we need to descend into
24subdir-ym := $(sort $(subdir-y) $(subdir-m) \
25			$(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
26
27# Handle objects in subdirs:
28# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
29#   foo/modules.order
30# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
31#
32# Generate modules.order to determine modorder. Unfortunately, we don't have
33# information about ordering between -y and -m subdirs. Just put -y's first.
34
35ifdef need-modorder
36obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
37else
38obj-m := $(filter-out %/, $(obj-m))
39endif
40
41ifdef need-builtin
42obj-y		:= $(patsubst %/, %/built-in.a, $(obj-y))
43else
44obj-y		:= $(filter-out %/, $(obj-y))
45endif
46
47# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
48suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
49# List composite targets that are constructed by combining other targets
50multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
51# List primitive targets that are compiled from source files
52real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
53
54# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
55multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
56multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
57multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
58
59# Replace multi-part objects by their individual parts,
60# including built-in.a from subdirectories
61real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
62real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
63
64always-y += $(always-m)
65
66# hostprogs-always-y += foo
67# ... is a shorthand for
68# hostprogs += foo
69# always-y  += foo
70hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
71always-y += $(hostprogs-always-y) $(hostprogs-always-m)
72
73# userprogs-always-y is likewise.
74userprogs += $(userprogs-always-y) $(userprogs-always-m)
75always-y += $(userprogs-always-y) $(userprogs-always-m)
76
77# DTB
78# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
79dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
80
81# Composite DTB (i.e. DTB constructed by overlay)
82multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs)
83# Primitive DTB compiled from *.dts
84real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs)
85# Base DTB that overlay is applied onto (each first word of $(*-dtbs) expansion)
86base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m, .dtb, -dtbs)))
87
88always-y			+= $(dtb-y)
89
90# Add subdir path
91
92extra-y		:= $(addprefix $(obj)/,$(extra-y))
93always-y	:= $(addprefix $(obj)/,$(always-y))
94targets		:= $(addprefix $(obj)/,$(targets))
95obj-m		:= $(addprefix $(obj)/,$(obj-m))
96lib-y		:= $(addprefix $(obj)/,$(lib-y))
97real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
98real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
99multi-obj-m	:= $(addprefix $(obj)/, $(multi-obj-m))
100multi-dtb-y	:= $(addprefix $(obj)/, $(multi-dtb-y))
101real-dtb-y	:= $(addprefix $(obj)/, $(real-dtb-y))
102subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))
103
104# Finds the multi-part object the current object will be linked into.
105# If the object belongs to two or more multi-part objects, list them all.
106modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
107		$(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
108
109__modname = $(or $(modname-multi),$(basetarget))
110
111modname = $(subst $(space),:,$(__modname))
112modfile = $(addprefix $(obj)/,$(__modname))
113
114# target with $(obj)/ and its suffix stripped
115target-stem = $(basename $(patsubst $(obj)/%,%,$@))
116
117# These flags are needed for modversions and compiling, so we define them here
118# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
119# end up in (or would, if it gets compiled in)
120name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
121name-fix = $(call stringify,$(call name-fix-token,$1))
122basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
123modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
124		 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
125modfile_flags  = -DKBUILD_MODFILE=$(call stringify,$(modfile))
126
127_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
128                     $(filter-out $(ccflags-remove-y), \
129                         $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
130                     $(CFLAGS_$(target-stem).o))
131_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
132                     $(filter-out $(asflags-remove-y), \
133                         $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
134                     $(AFLAGS_$(target-stem).o))
135_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
136
137#
138# Enable gcov profiling flags for a file, directory or for all files depending
139# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
140# (in this order)
141#
142ifeq ($(CONFIG_GCOV_KERNEL),y)
143_c_flags += $(if $(patsubst n%,, \
144		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
145		$(CFLAGS_GCOV))
146endif
147
148#
149# Enable address sanitizer flags for kernel except some files or directories
150# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
151#
152ifeq ($(CONFIG_KASAN),y)
153ifneq ($(CONFIG_KASAN_HW_TAGS),y)
154_c_flags += $(if $(patsubst n%,, \
155		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
156		$(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
157endif
158endif
159
160ifeq ($(CONFIG_KMSAN),y)
161_c_flags += $(if $(patsubst n%,, \
162		$(KMSAN_SANITIZE_$(basetarget).o)$(KMSAN_SANITIZE)y), \
163		$(CFLAGS_KMSAN))
164_c_flags += $(if $(patsubst n%,, \
165		$(KMSAN_ENABLE_CHECKS_$(basetarget).o)$(KMSAN_ENABLE_CHECKS)y), \
166		, -mllvm -msan-disable-checks=1)
167endif
168
169ifeq ($(CONFIG_UBSAN),y)
170_c_flags += $(if $(patsubst n%,, \
171		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
172		$(CFLAGS_UBSAN))
173endif
174
175ifeq ($(CONFIG_KCOV),y)
176_c_flags += $(if $(patsubst n%,, \
177	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
178	$(CFLAGS_KCOV))
179endif
180
181#
182# Enable KCSAN flags except some files or directories we don't want to check
183# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
184#
185ifeq ($(CONFIG_KCSAN),y)
186_c_flags += $(if $(patsubst n%,, \
187	$(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \
188	$(CFLAGS_KCSAN))
189# Some uninstrumented files provide implied barriers required to avoid false
190# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only.
191_c_flags += $(if $(patsubst n%,, \
192	$(KCSAN_INSTRUMENT_BARRIERS_$(basetarget).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \
193	-D__KCSAN_INSTRUMENT_BARRIERS__)
194endif
195
196# $(srctree)/$(src) for including checkin headers from generated source files
197# $(objtree)/$(obj) for including generated headers from checkin source files
198ifeq ($(KBUILD_EXTMOD),)
199ifdef building_out_of_srctree
200_c_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
201_a_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
202_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
203endif
204endif
205
206part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
207quiet_modtag = $(if $(part-of-module),[M],   )
208
209modkern_cflags =                                          \
210	$(if $(part-of-module),                           \
211		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
212		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
213
214modkern_aflags = $(if $(part-of-module),				\
215			$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),	\
216			$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
217
218c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
219		 -include $(srctree)/include/linux/compiler_types.h       \
220		 $(_c_flags) $(modkern_cflags)                           \
221		 $(basename_flags) $(modname_flags)
222
223a_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
224		 $(_a_flags) $(modkern_aflags)
225
226cpp_flags      = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
227		 $(_cpp_flags)
228
229ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
230
231DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes
232
233dtc_cpp_flags  = -Wp,-MMD,$(depfile).pre.tmp -nostdinc                    \
234		 $(addprefix -I,$(DTC_INCLUDE))                          \
235		 -undef -D__DTS__
236
237ifdef CONFIG_OBJTOOL
238
239objtool := $(objtree)/tools/objtool/objtool
240
241objtool_args =								\
242	$(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label)	\
243	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
244	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
245	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
246	$(if $(CONFIG_UNWINDER_ORC), --orc)				\
247	$(if $(CONFIG_RETPOLINE), --retpoline)				\
248	$(if $(CONFIG_RETHUNK), --rethunk)				\
249	$(if $(CONFIG_SLS), --sls)					\
250	$(if $(CONFIG_STACK_VALIDATION), --stackval)			\
251	$(if $(CONFIG_HAVE_STATIC_CALL_INLINE), --static-call)		\
252	$(if $(CONFIG_HAVE_UACCESS_VALIDATION), --uaccess)		\
253	$(if $(delay-objtool), --link)					\
254	$(if $(part-of-module), --module)				\
255	$(if $(CONFIG_GCOV_KERNEL), --no-unreachable)
256
257delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
258
259cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@)
260cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
261
262endif # CONFIG_OBJTOOL
263
264# Useful for describing the dependency of composite objects
265# Usage:
266#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
267define multi_depend
268$(foreach m, $1, \
269	$(eval $m: \
270	$(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3))))
271endef
272
273# Copy a file
274# ===========================================================================
275# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
276# the copy would be read-only as well, leading to an error when executing the
277# rule next time. Use 'cat' instead in order to generate a writable file.
278quiet_cmd_copy = COPY    $@
279      cmd_copy = cat $< > $@
280
281$(obj)/%: $(src)/%_shipped
282	$(call cmd,copy)
283
284# Commands useful for building a boot image
285# ===========================================================================
286#
287#	Use as following:
288#
289#	target: source(s) FORCE
290#		$(if_changed,ld/objcopy/gzip)
291#
292#	and add target to 'targets' so that we know we have to
293#	read in the saved command line
294
295# Linking
296# ---------------------------------------------------------------------------
297
298quiet_cmd_ld = LD      $@
299      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
300
301# Archive
302# ---------------------------------------------------------------------------
303
304quiet_cmd_ar = AR      $@
305      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
306
307# Objcopy
308# ---------------------------------------------------------------------------
309
310quiet_cmd_objcopy = OBJCOPY $@
311cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
312
313# Gzip
314# ---------------------------------------------------------------------------
315
316quiet_cmd_gzip = GZIP    $@
317      cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
318
319# DTC
320# ---------------------------------------------------------------------------
321DTC ?= $(objtree)/scripts/dtc/dtc
322DTC_FLAGS += -Wno-interrupt_provider
323
324# Disable noisy checks by default
325ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
326DTC_FLAGS += -Wno-unit_address_vs_reg \
327	-Wno-avoid_unnecessary_addr_size \
328	-Wno-alias_paths \
329	-Wno-graph_child_address \
330	-Wno-simple_bus_reg \
331	-Wno-unique_unit_address
332endif
333
334ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
335DTC_FLAGS += -Wnode_name_chars_strict \
336	-Wproperty_name_chars_strict \
337	-Winterrupt_provider
338endif
339
340DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
341
342# Set -@ if the target is a base DTB that overlay is applied onto
343DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
344
345# Generate an assembly file to wrap the output of the device tree compiler
346quiet_cmd_dt_S_dtb= DTB     $@
347cmd_dt_S_dtb=						\
348{							\
349	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\
350	echo '.section .dtb.init.rodata,"a"';		\
351	echo '.balign STRUCT_ALIGNMENT';		\
352	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
353	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
354	echo '.incbin "$<" ';				\
355	echo '__dtb_$(subst -,_,$(*F))_end:';		\
356	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
357	echo '.balign STRUCT_ALIGNMENT'; 		\
358} > $@
359
360$(obj)/%.dtb.S: $(obj)/%.dtb FORCE
361	$(call if_changed,dt_S_dtb)
362
363quiet_cmd_dtc = DTC     $@
364cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
365	$(DTC) -o $@ -b 0 \
366		$(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
367		-d $(depfile).dtc.tmp $(dtc-tmp) ; \
368	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
369
370quiet_cmd_fdtoverlay = DTOVL   $@
371      cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
372
373$(multi-dtb-y): FORCE
374	$(call if_changed,fdtoverlay)
375$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
376
377ifneq ($(CHECK_DTBS)$(CHECK_DT_BINDING),)
378DT_CHECKER ?= dt-validate
379DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),-l $(DT_SCHEMA_FILES),-m)
380DT_BINDING_DIR := Documentation/devicetree/bindings
381DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
382
383quiet_cmd_dtb_check =	CHECK   $@
384      cmd_dtb_check =	$(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true
385endif
386
387define rule_dtc
388	$(call cmd_and_fixdep,dtc)
389	$(call cmd,dtb_check)
390endef
391
392$(obj)/%.dtb: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
393	$(call if_changed_rule,dtc)
394
395$(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
396	$(call if_changed_dep,dtc)
397
398dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
399
400# Bzip2
401# ---------------------------------------------------------------------------
402
403# Bzip2 and LZMA do not include size in file... so we have to fake that;
404# append the size as a 32-bit littleendian number as gzip does.
405size_append = printf $(shell						\
406dec_size=0;								\
407for F in $(real-prereqs); do					\
408	fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);	\
409	dec_size=$$(expr $$dec_size + $$fsize);				\
410done;									\
411printf "%08x\n" $$dec_size |						\
412	sed 's/\(..\)/\1 /g' | {					\
413		read ch0 ch1 ch2 ch3;					\
414		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
415			printf '%s%03o' '\\' $$((0x$$ch)); 		\
416		done;							\
417	}								\
418)
419
420quiet_cmd_file_size = GEN     $@
421      cmd_file_size = $(size_append) > $@
422
423quiet_cmd_bzip2 = BZIP2   $@
424      cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@
425
426quiet_cmd_bzip2_with_size = BZIP2   $@
427      cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
428
429# Lzma
430# ---------------------------------------------------------------------------
431
432quiet_cmd_lzma = LZMA    $@
433      cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@
434
435quiet_cmd_lzma_with_size = LZMA    $@
436      cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
437
438quiet_cmd_lzo = LZO     $@
439      cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@
440
441quiet_cmd_lzo_with_size = LZO     $@
442      cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
443
444quiet_cmd_lz4 = LZ4     $@
445      cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout > $@
446
447quiet_cmd_lz4_with_size = LZ4     $@
448      cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout; \
449                  $(size_append); } > $@
450
451# U-Boot mkimage
452# ---------------------------------------------------------------------------
453
454MKIMAGE := $(srctree)/scripts/mkuboot.sh
455
456# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
457# the number of overrides in arch makefiles
458UIMAGE_ARCH ?= $(SRCARCH)
459UIMAGE_COMPRESSION ?= $(or $(2),none)
460UIMAGE_OPTS-y ?=
461UIMAGE_TYPE ?= kernel
462UIMAGE_LOADADDR ?= arch_must_set_this
463UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
464UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
465
466quiet_cmd_uimage = UIMAGE  $@
467      cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
468			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
469			-T $(UIMAGE_TYPE) \
470			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
471			-n $(UIMAGE_NAME) -d $< $@
472
473# XZ
474# ---------------------------------------------------------------------------
475# Use xzkern to compress the kernel image and xzmisc to compress other things.
476#
477# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
478# of the kernel decompressor. A BCJ filter is used if it is available for
479# the target architecture. xzkern also appends uncompressed size of the data
480# using size_append. The .xz format has the size information available at
481# the end of the file too, but it's in more complex format and it's good to
482# avoid changing the part of the boot code that reads the uncompressed size.
483# Note that the bytes added by size_append will make the xz tool think that
484# the file is corrupt. This is expected.
485#
486# xzmisc doesn't use size_append, so it can be used to create normal .xz
487# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
488# big dictionary would increase the memory usage too much in the multi-call
489# decompression mode. A BCJ filter isn't used either.
490quiet_cmd_xzkern = XZKERN  $@
491      cmd_xzkern = cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@
492
493quiet_cmd_xzkern_with_size = XZKERN  $@
494      cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
495                     $(size_append); } > $@
496
497quiet_cmd_xzmisc = XZMISC  $@
498      cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
499
500# ZSTD
501# ---------------------------------------------------------------------------
502# Appends the uncompressed size of the data using size_append. The .zst
503# format has the size information available at the beginning of the file too,
504# but it's in a more complex format and it's good to avoid changing the part
505# of the boot code that reads the uncompressed size.
506#
507# Note that the bytes added by size_append will make the zstd tool think that
508# the file is corrupt. This is expected.
509#
510# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
511# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
512# single pass, so zstd doesn't need to allocate a window buffer. When streaming
513# decompression is used, like initramfs decompression, zstd22 should likely not
514# be used because it would require zstd to allocate a 128 MB buffer.
515
516quiet_cmd_zstd = ZSTD    $@
517      cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@
518
519quiet_cmd_zstd22 = ZSTD22  $@
520      cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@
521
522quiet_cmd_zstd22_with_size = ZSTD22  $@
523      cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
524
525# ASM offsets
526# ---------------------------------------------------------------------------
527
528# Default sed regexp - multiline due to syntax constraints
529#
530# Use [:space:] because LLVM's integrated assembler inserts <tab> around
531# the .ascii directive whereas GCC keeps the <space> as-is.
532define sed-offsets
533	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
534	/^->/{s:->#\(.*\):/* \1 */:; \
535	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
536	s:->::; p;}'
537endef
538
539# Use filechk to avoid rebuilds when a header changes, but the resulting file
540# does not
541define filechk_offsets
542	 echo "#ifndef $2"; \
543	 echo "#define $2"; \
544	 echo "/*"; \
545	 echo " * DO NOT MODIFY."; \
546	 echo " *"; \
547	 echo " * This file was generated by Kbuild"; \
548	 echo " */"; \
549	 echo ""; \
550	 sed -ne $(sed-offsets) < $<; \
551	 echo ""; \
552	 echo "#endif"
553endef
554