This repository has been archived by the owner on Jun 19, 2022. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Makefile
1342 lines (1091 loc) · 42.2 KB
/
Makefile
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
VERSION = 1
PATCHLEVEL = 22
SUBLEVEL = 0
EXTRAVERSION = .git
NAME = Unnamed
# *DOCUMENTATION*
# To see a list of typical targets execute "make help"
# More info can be located in ./README
# Comments in this file are targeted only to the developer, do not
# expect to learn how to build the kernel reading this file.
# Do not print "Entering directory ..."
MAKEFLAGS += --no-print-directory
# We are using a recursive build, so we need to do a little thinking
# to get the ordering right.
#
# Most importantly: sub-Makefiles should only ever modify files in
# their own directory. If in some directory we have a dependency on
# a file in another dir (which doesn't happen often, but it's often
# unavoidable when linking the built-in.o targets which finally
# turn into busybox), we will call a sub make in that other dir, and
# after that we are sure that everything which is in that other dir
# is now up to date.
#
# The only cases where we need to modify files which have global
# effects are thus separated out and done before the recursive
# descending is started. They are now explicitly listed as the
# prepare rule.
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands
ifdef V
ifeq ("$(origin V)", "command line")
KBUILD_VERBOSE = $(V)
endif
endif
ifndef KBUILD_VERBOSE
KBUILD_VERBOSE = 0
endif
# Call sparse as part of compilation of C files
# Use 'make C=1' to enable sparse checking
ifdef C
ifeq ("$(origin C)", "command line")
KBUILD_CHECKSRC = $(C)
endif
endif
ifndef KBUILD_CHECKSRC
KBUILD_CHECKSRC = 0
endif
# Use make M=dir to specify directory of external module to build
# Old syntax make ... SUBDIRS=$PWD is still supported
# Setting the environment variable KBUILD_EXTMOD take precedence
ifdef SUBDIRS
KBUILD_EXTMOD ?= $(SUBDIRS)
endif
ifdef M
ifeq ("$(origin M)", "command line")
KBUILD_EXTMOD := $(M)
endif
endif
# kbuild supports saving output files in a separate directory.
# To locate output files in a separate directory two syntaxes are supported.
# In both cases the working directory must be the root of the kernel src.
# 1) O=
# Use "make O=dir/to/store/output/files/"
#
# 2) Set KBUILD_OUTPUT
# Set the environment variable KBUILD_OUTPUT to point to the directory
# where the output files shall be placed.
# export KBUILD_OUTPUT=dir/to/store/output/files/
# make
#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.
# KBUILD_SRC is set on invocation of make in OBJ directory
# KBUILD_SRC is not intended to be used by the regular user (for now)
ifeq ($(KBUILD_SRC),)
# OK, Make called in directory where kernel src resides
# Do we want to locate output files in a separate directory?
ifdef O
ifeq ("$(origin O)", "command line")
KBUILD_OUTPUT := $(O)
endif
endif
# That's our default target when none is given on the command line
PHONY := _all
_all:
ifneq ($(KBUILD_OUTPUT),)
# Invoke a second make in the output directory, passing relevant variables
# check that the output directory actually exists
saved-output := $(KBUILD_OUTPUT)
KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
$(if $(KBUILD_OUTPUT),, \
$(error output directory "$(saved-output)" does not exist))
PHONY += $(MAKECMDGOALS)
$(filter-out _all,$(MAKECMDGOALS)) _all:
$(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
KBUILD_SRC=$(CURDIR) \
KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile $@
# Leave processing to above invocation of make
skip-makefile := 1
endif # ifneq ($(KBUILD_OUTPUT),)
endif # ifeq ($(KBUILD_SRC),)
# We process the rest of the Makefile if this is the final invocation of make
ifeq ($(skip-makefile),)
# If building an external module we do not care about the all: rule
# but instead _all depend on modules
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
_all: all
else
_all: modules
endif
srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
TOPDIR := $(srctree)
# FIXME - TOPDIR is obsolete, use srctree/objtree
objtree := $(CURDIR)
src := $(srctree)
obj := $(objtree)
VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
export srctree objtree VPATH TOPDIR
# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
#
# When performing cross compilation for other architectures ARCH shall be set
# to the target architecture. (See arch/* for the possibilities).
# ARCH can be set during invocation of make:
# make ARCH=ia64
# Another way is to have ARCH set in the environment.
# The default ARCH is the host where make is executed.
# CROSS_COMPILE specify the prefix used for all executables used
# during compilation. Only gcc and related bin-utils executables
# are prefixed with $(CROSS_COMPILE).
# CROSS_COMPILE can be set on the command line
# make CROSS_COMPILE=ia64-linux-
# Alternatively CROSS_COMPILE can be set in the environment.
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
CROSS_COMPILE ?=
# bbox: we may have CONFIG_CROSS_COMPILER_PREFIX in .config,
# and it has not been included yet... thus using an awkward syntax.
ifeq ($(CROSS_COMPILE),)
CROSS_COMPILE := $(shell grep ^CONFIG_CROSS_COMPILER_PREFIX .config 2>/dev/null)
CROSS_COMPILE := $(subst CONFIG_CROSS_COMPILER_PREFIX=,,$(CROSS_COMPILE))
CROSS_COMPILE := $(subst ",,$(CROSS_COMPILE))
#")
endif
# SUBARCH tells the usermode build what the underlying arch is. That is set
# first, and if a usermode build is happening, the "ARCH=um" on the command
# line overrides the setting of ARCH below. If a native build is happening,
# then ARCH is assigned, getting whatever value it gets normally, and
# SUBARCH is subsequently ignored.
ifneq ($(CROSS_COMPILE),)
SUBARCH := $(shell echo $(CROSS_COMPILE) | cut -d- -f1)
else
SUBARCH := $(shell uname -m)
endif
SUBARCH := $(shell echo $(SUBARCH) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
-e s/arm.*/arm/ -e s/sa110/arm/ \
-e s/s390x/s390/ -e s/parisc64/parisc/ \
-e s/ppc.*/powerpc/ -e s/mips.*/mips/ )
ARCH ?= $(SUBARCH)
# Architecture as present in compile.h
UTS_MACHINE := $(ARCH)
# SHELL used by kbuild
CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
else if [ -x /bin/bash ]; then echo /bin/bash; \
else echo sh; fi ; fi)
# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.
KBUILD_MODULES :=
KBUILD_BUILTIN := 1
# If we have only "make modules", don't compile built-in objects.
# When we're building modules with modversions, we need to consider
# the built-in objects during the descend as well, in order to
# make sure the checksums are uptodate before we record them.
ifeq ($(MAKECMDGOALS),modules)
KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
endif
# If we have "make <whatever> modules", compile modules
# in addition to whatever we do anyway.
# Just "make" or "make all" shall build modules as well
ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
KBUILD_MODULES := 1
endif
ifeq ($(MAKECMDGOALS),)
KBUILD_MODULES := 1
endif
export KBUILD_MODULES KBUILD_BUILTIN
export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
# Beautify output
# ---------------------------------------------------------------------------
#
# Normally, we echo the whole command before executing it. By making
# that echo $($(quiet)$(cmd)), we now have the possibility to set
# $(quiet) to choose other forms of output instead, e.g.
#
# quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
# cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
#
# If $(quiet) is empty, the whole command will be printed.
# If it is set to "quiet_", only the short version will be printed.
# If it is set to "silent_", nothing wil be printed at all, since
# the variable $(silent_cmd_cc_o_c) doesn't exist.
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
# $(Q)ln $@ :<
#
# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
# If KBUILD_VERBOSE equals 1 then the above command is displayed.
ifeq ($(KBUILD_VERBOSE),1)
quiet =
Q =
else
quiet=quiet_
Q = @
endif
# If the user is running make -s (silent mode), suppress echoing of
# commands
ifneq ($(findstring s,$(MAKEFLAGS)),)
quiet=silent_
endif
export quiet Q KBUILD_VERBOSE
# Look for make include files relative to root of kernel src
MAKEFLAGS += --include-dir=$(srctree)
HOSTCC = gcc
HOSTCXX = g++
HOSTCFLAGS :=
HOSTCXXFLAGS :=
# We need some generic definitions
include $(srctree)/scripts/Kbuild.include
HOSTCFLAGS += $(call hostcc-option,-Wall -Wstrict-prototypes -O2 -fomit-frame-pointer,)
HOSTCXXFLAGS += -O2
# For maximum performance (+ possibly random breakage, uncomment
# the following)
MAKEFLAGS += -rR
# Make variables (CC, etc...)
AS = $(CROSS_COMPILE)as
CC = $(CROSS_COMPILE)gcc
LD = $(CC) -nostdlib
CPP = $(CC) -E
AR = $(CROSS_COMPILE)ar
NM = $(CROSS_COMPILE)nm
STRIP = $(CROSS_COMPILE)strip
OBJCOPY = $(CROSS_COMPILE)objcopy
OBJDUMP = $(CROSS_COMPILE)objdump
PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
AWK = awk
GENKSYMS = scripts/genksyms/genksyms
DEPMOD = /sbin/depmod
KALLSYMS = scripts/kallsyms
PERL = perl
CHECK = sparse
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise $(CF)
MODFLAGS = -DMODULE
CFLAGS_MODULE = $(MODFLAGS)
AFLAGS_MODULE = $(MODFLAGS)
LDFLAGS_MODULE = -r
CFLAGS_KERNEL =
AFLAGS_KERNEL =
# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
CFLAGS := $(CFLAGS)
# Added only to final link stage of busybox binary
CFLAGS_busybox := $(CFLAGS_busybox)
CPPFLAGS := $(CPPFLAGS)
AFLAGS := $(AFLAGS)
LDFLAGS := $(LDFLAGS)
LDLIBS :=
# Read KERNELRELEASE from .kernelrelease (if it exists)
KERNELRELEASE = $(shell cat .kernelrelease 2> /dev/null)
KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION \
ARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE \
HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
export CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
export FLTFLAGS
# When compiling out-of-tree modules, put MODVERDIR in the module
# tree rather than in the kernel tree. The kernel tree might
# even be read-only.
export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
# Files to ignore in find ... statements
RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o
export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
# ===========================================================================
# Rules shared between *config targets and build targets
# Basic helpers built in scripts/
PHONY += scripts_basic
scripts_basic:
$(Q)$(MAKE) $(build)=scripts/basic
# To avoid any implicit rule to kick in, define an empty command.
scripts/basic/%: scripts_basic ;
# This target generates Kbuild's and Config.in's from *.c files
PHONY += gen_build_files
gen_build_files: $(wildcard $(srctree)/*/*.c) $(wildcard $(srctree)/*/*/*.c)
$(Q)$(srctree)/scripts/gen_build_files.sh $(srctree) $(objtree)
# bbox: we have helpers in applets/
# we depend on scripts_basic, since scripts/basic/fixdep
# must be built before any other host prog
PHONY += applets_dir
applets_dir: scripts_basic gen_build_files
$(Q)$(MAKE) $(build)=applets
applets/%: applets_dir ;
PHONY += outputmakefile
# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
outputmakefile:
ifneq ($(KBUILD_SRC),)
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
$(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
endif
# To make sure we do not include .config for any of the *config targets
# catch them early, and hand them over to scripts/kconfig/Makefile
# It is allowed to specify more targets when calling make, including
# mixing *config targets and build targets.
# For example 'make oldconfig all'.
# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).
no-dot-config-targets := clean mrproper distclean \
cscope TAGS tags help %docs
#bbox# check% is removed from above
config-targets := 0
mixed-targets := 0
dot-config := 1
ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
dot-config := 0
endif
endif
ifeq ($(KBUILD_EXTMOD),)
ifneq ($(filter config %config,$(MAKECMDGOALS)),)
config-targets := 1
ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
mixed-targets := 1
endif
endif
endif
ifeq ($(mixed-targets),1)
# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.
%:: FORCE
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
else
ifeq ($(config-targets),1)
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
# in scripts/kconfig to make the *config target
# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
-include $(srctree)/arch/$(ARCH)/Makefile
export KBUILD_DEFCONFIG
config: scripts_basic outputmakefile gen_build_files FORCE
$(Q)mkdir -p include
$(Q)$(MAKE) $(build)=scripts/kconfig $@
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= .kernelrelease
%config: scripts_basic outputmakefile gen_build_files FORCE
$(Q)mkdir -p include
$(Q)$(MAKE) $(build)=scripts/kconfig $@
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= .kernelrelease
else
# ===========================================================================
# Build targets only - this includes busybox, arch specific targets, clean
# targets and others. In general all targets except *config targets.
ifeq ($(KBUILD_EXTMOD),)
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
scripts: gen_build_files scripts_basic include/config/MARKER
$(Q)$(MAKE) $(build)=$(@)
scripts_basic: include/autoconf.h
# Objects we will link into busybox / subdirs we need to visit
core-y := \
applets/ \
libs-y := \
archival/ \
archival/libarchive/ \
console-tools/ \
coreutils/ \
coreutils/libcoreutils/ \
debianutils/ \
e2fsprogs/ \
editors/ \
findutils/ \
init/ \
libbb/ \
libpwdgrp/ \
loginutils/ \
mailutils/ \
miscutils/ \
modutils/ \
networking/ \
networking/libiproute/ \
networking/udhcp/ \
printutils/ \
procps/ \
runit/ \
selinux/ \
shell/ \
sysklogd/ \
util-linux/ \
util-linux/volume_id/ \
endif # KBUILD_EXTMOD
ifeq ($(dot-config),1)
# In this section, we need .config
# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
-include .kconfig.d
-include .config
# If .config needs to be updated, it will be done via the dependency
# that autoconf has on .config.
# To avoid any implicit rule to kick in, define an empty command
.config .kconfig.d: ;
# Now we can define CFLAGS etc according to .config
include $(srctree)/Makefile.flags
# If .config is newer than include/autoconf.h, someone tinkered
# with it and forgot to run make oldconfig.
# If kconfig.d is missing then we are probarly in a cleaned tree so
# we execute the config step to be sure to catch updated Kconfig files
include/autoconf.h: .kconfig.d .config $(wildcard $(srctree)/*/*.c) $(wildcard $(srctree)/*/*/*.c) | gen_build_files
$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
include/usage.h: gen_build_files
else
# Dummy target needed, because used as prerequisite
include/autoconf.h: ;
endif
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults busybox but it is usually overridden in the arch makefile
all: busybox doc
-include $(srctree)/arch/$(ARCH)/Makefile
# arch Makefile may override CC so keep this after arch Makefile is included
#bbox# NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
CHECKFLAGS += $(NOSTDINC_FLAGS)
# Default kernel image to build when no specific target is given.
# KBUILD_IMAGE may be overruled on the commandline or
# set in the environment
# Also any assignments in arch/$(ARCH)/Makefile take precedence over
# this default value
export KBUILD_IMAGE ?= busybox
#
# INSTALL_PATH specifies where to place the updated kernel and system map
# images. Default is /boot, but you can set it to other values
export INSTALL_PATH ?= /boot
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots. This is not defined in the
# makefile but the arguement can be passed to make if needed.
#
MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
export MODLIB
ifeq ($(KBUILD_EXTMOD),)
busybox-dirs := $(patsubst %/,%,$(filter %/, $(core-y) $(core-m) $(libs-y) $(libs-m)))
busybox-alldirs := $(sort $(busybox-dirs) $(patsubst %/,%,$(filter %/, \
$(core-n) $(core-) $(libs-n) $(libs-) \
)))
core-y := $(patsubst %/, %/built-in.o, $(core-y))
libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
libs-y := $(libs-y1) $(libs-y2)
# Build busybox
# ---------------------------------------------------------------------------
# busybox is build from the objects selected by $(busybox-init) and
# $(busybox-main). Most are built-in.o files from top-level directories
# in the kernel tree, others are specified in arch/$(ARCH)Makefile.
# Ordering when linking is important, and $(busybox-init) must be first.
#
# busybox
# ^
# |
# +-< $(busybox-init)
# | +--< init/version.o + more
# |
# +--< $(busybox-main)
# | +--< driver/built-in.o mm/built-in.o + more
# |
# +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
#
# busybox version (uname -v) cannot be updated during normal
# descending-into-subdirs phase since we do not yet know if we need to
# update busybox.
# Therefore this step is delayed until just before final link of busybox -
# except in the kallsyms case where it is done just before adding the
# symbols to the kernel.
#
# System.map is generated to document addresses of all kernel symbols
busybox-all := $(core-y) $(libs-y)
# Rule to link busybox - also used during CONFIG_KALLSYMS
# May be overridden by arch/$(ARCH)/Makefile
quiet_cmd_busybox__ ?= LINK $@
cmd_busybox__ ?= $(srctree)/scripts/trylink \
"$@" \
"$(CC)" \
"$(CFLAGS) $(CFLAGS_busybox)" \
"$(LDFLAGS) $(EXTRA_LDFLAGS)" \
"$(core-y)" \
"$(libs-y)" \
"$(LDLIBS)"
# Generate System.map
quiet_cmd_sysmap = SYSMAP
cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
# Link of busybox
# If CONFIG_KALLSYMS is set .version is already updated
# Generate System.map and verify that the content is consistent
# Use + in front of the busybox_version rule to silent warning with make -j2
# First command is ':' to allow us to use + in front of the rule
define rule_busybox__
:
$(call cmd,busybox__)
$(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
endef
ifdef CONFIG_KALLSYMS
# Generate section listing all symbols and add it into busybox $(kallsyms.o)
# It's a three stage process:
# o .tmp_busybox1 has all symbols and sections, but __kallsyms is
# empty
# Running kallsyms on that gives us .tmp_kallsyms1.o with
# the right size - busybox version (uname -v) is updated during this step
# o .tmp_busybox2 now has a __kallsyms section of the right size,
# but due to the added section, some addresses have shifted.
# From here, we generate a correct .tmp_kallsyms2.o
# o The correct .tmp_kallsyms2.o is linked into the final busybox.
# o Verify that the System.map from busybox matches the map from
# .tmp_busybox2, just in case we did not generate kallsyms correctly.
# o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
# .tmp_busybox3 and .tmp_kallsyms3.o. This is only meant as a
# temporary bypass to allow the kernel to be built while the
# maintainers work out what went wrong with kallsyms.
ifdef CONFIG_KALLSYMS_EXTRA_PASS
last_kallsyms := 3
else
last_kallsyms := 2
endif
kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
define verify_kallsyms
$(Q)$(if $($(quiet)cmd_sysmap), \
echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
$(cmd_sysmap) .tmp_busybox$(last_kallsyms) .tmp_System.map
$(Q)cmp -s System.map .tmp_System.map || \
(echo Inconsistent kallsyms data; \
echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
rm .tmp_kallsyms* ; /bin/false )
endef
# Update busybox version before link
# Use + in front of this rule to silent warning about make -j1
# First command is ':' to allow us to use + in front of this rule
cmd_ksym_ld = $(cmd_busybox__)
define rule_ksym_ld
:
+$(call cmd,busybox_version)
$(call cmd,busybox__)
$(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
endef
# Generate .S file with all kernel symbols
quiet_cmd_kallsyms = KSYM $@
cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
$(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
$(call if_changed_dep,as_o_S)
.tmp_kallsyms%.S: .tmp_busybox% $(KALLSYMS)
$(call cmd,kallsyms)
# .tmp_busybox1 must be complete except kallsyms, so update busybox version
.tmp_busybox1: $(busybox-lds) $(busybox-all) FORCE
$(call if_changed_rule,ksym_ld)
.tmp_busybox2: $(busybox-lds) $(busybox-all) .tmp_kallsyms1.o FORCE
$(call if_changed,busybox__)
.tmp_busybox3: $(busybox-lds) $(busybox-all) .tmp_kallsyms2.o FORCE
$(call if_changed,busybox__)
# Needs to visit scripts/ before $(KALLSYMS) can be used.
$(KALLSYMS): scripts ;
# Generate some data for debugging strange kallsyms problems
debug_kallsyms: .tmp_map$(last_kallsyms)
.tmp_map%: .tmp_busybox% FORCE
($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
.tmp_map3: .tmp_map2
.tmp_map2: .tmp_map1
endif # ifdef CONFIG_KALLSYMS
# busybox image - including updated kernel symbols
busybox_unstripped: $(busybox-all) FORCE
$(call if_changed_rule,busybox__)
$(Q)rm -f .old_version
busybox: busybox_unstripped
ifeq ($(SKIP_STRIP),y)
$(Q)cp $< $@
else
$(Q)$(STRIP) -s --remove-section=.note --remove-section=.comment \
busybox_unstripped -o $@
# strip is confused by PIE executable and does not set exec bits
$(Q)chmod a+x $@
endif
# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(busybox-all)): $(busybox-dirs) ;
# Handle descending into subdirectories listed in $(busybox-dirs)
# Preset locale variables to speed up the build process. Limit locale
# tweaks to this spot to avoid wrong language settings when running
# make menuconfig etc.
# Error messages still appears in the original language
PHONY += $(busybox-dirs)
$(busybox-dirs): prepare scripts
$(Q)$(MAKE) $(build)=$@
# Build the kernel release string
# The KERNELRELEASE is stored in a file named .kernelrelease
# to be used when executing for example make install or make modules_install
#
# Take the contents of any files called localversion* and the config
# variable CONFIG_LOCALVERSION and append them to KERNELRELEASE.
# LOCALVERSION from the command line override all of this
nullstring :=
space := $(nullstring) # end of line
___localver = $(objtree)/localversion* $(srctree)/localversion*
__localver = $(sort $(wildcard $(___localver)))
# skip backup files (containing '~')
_localver = $(foreach f, $(__localver), $(if $(findstring ~, $(f)),,$(f)))
localver = $(subst $(space),, \
$(shell cat /dev/null $(_localver)) \
$(patsubst "%",%,$(CONFIG_LOCALVERSION)))
# If CONFIG_LOCALVERSION_AUTO is set scripts/setlocalversion is called
# and if the SCM is know a tag from the SCM is appended.
# The appended tag is determinded by the SCM used.
#
# Currently, only git is supported.
# Other SCMs can edit scripts/setlocalversion and add the appropriate
# checks as needed.
ifdef _BB_DISABLED_CONFIG_LOCALVERSION_AUTO
_localver-auto = $(shell $(CONFIG_SHELL) \
$(srctree)/scripts/setlocalversion $(srctree))
localver-auto = $(LOCALVERSION)$(_localver-auto)
endif
localver-full = $(localver)$(localver-auto)
# Store (new) KERNELRELASE string in .kernelrelease
kernelrelease = $(KERNELVERSION)$(localver-full)
.kernelrelease: FORCE
$(Q)rm -f $@
$(Q)echo $(kernelrelease) > $@
# Things we need to do before we recursively start building the kernel
# or the modules are listed in "prepare".
# A multi level approach is used. prepareN is processed before prepareN-1.
# archprepare is used in arch Makefiles and when processed asm symlink,
# version.h and scripts_basic is processed / created.
# Listed in dependency order
PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
# prepare-all is deprecated, use prepare as valid replacement
PHONY += prepare-all
# prepare3 is used to check if we are building in a separate output directory,
# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
# 2) Create the include2 directory, used for the second asm symlink
prepare3: .kernelrelease
ifneq ($(KBUILD_SRC),)
@echo ' Using $(srctree) as source for busybox'
$(Q)if [ -f $(srctree)/.config ]; then \
echo " $(srctree) is not clean, please run 'make mrproper'";\
echo " in the '$(srctree)' directory.";\
/bin/false; \
fi;
$(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
$(Q)ln -fsn $(srctree)/include/asm-$(ARCH) include2/asm
endif
# prepare2 creates a makefile if using a separate output directory
prepare2: prepare3 outputmakefile
prepare1: prepare2 include/config/MARKER
ifneq ($(KBUILD_MODULES),)
$(Q)mkdir -p $(MODVERDIR)
$(Q)rm -f $(MODVERDIR)/*
endif
archprepare: prepare1 scripts_basic applets_dir
prepare0: archprepare FORCE
$(Q)$(MAKE) $(build)=.
# All the preparing..
prepare prepare-all: prepare0
# Leave this as default for preprocessing busybox.lds.S, which is now
# done in arch/$(ARCH)/kernel/Makefile
export CPPFLAGS_busybox.lds += -P -C -U$(ARCH)
# FIXME: The asm symlink changes when $(ARCH) changes. That's
# hard to detect, but I suppose "make mrproper" is a good idea
# before switching between archs anyway.
#bbox# include/asm:
#bbox# @echo ' SYMLINK $@ -> include/asm-$(ARCH)'
#bbox# $(Q)if [ ! -d include ]; then mkdir -p include; fi;
#bbox# @ln -fsn asm-$(ARCH) $@
# Split autoconf.h into include/linux/config/*
quiet_cmd_gen_bbconfigopts = GEN include/bbconfigopts.h
cmd_gen_bbconfigopts = $(srctree)/scripts/mkconfigs include/bbconfigopts.h include/bbconfigopts_bz2.h
quiet_cmd_split_autoconf = SPLIT include/autoconf.h -> include/config/*
cmd_split_autoconf = scripts/basic/split-include include/autoconf.h include/config
#bbox# piggybacked generation of few .h files
include/config/MARKER: scripts/basic/split-include include/autoconf.h
$(call cmd,split_autoconf)
$(call cmd,gen_bbconfigopts)
@touch $@
# Generate some files
# ---------------------------------------------------------------------------
# KERNELRELEASE can change from a few different places, meaning version.h
# needs to be updated, so this check is forced on all builds
uts_len := 64
define filechk_version.h
if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
exit 1; \
fi; \
(echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"; \
echo \#define LINUX_VERSION_CODE `expr $(VERSION) \\* 65536 + $(PATCHLEVEL) \\* 256 + $(SUBLEVEL)`; \
echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'; \
)
endef
# ---------------------------------------------------------------------------
PHONY += depend dep
depend dep:
@echo '*** Warning: make $@ is unnecessary now.'
# ---------------------------------------------------------------------------
# Modules
ifdef _BB_DISABLED_CONFIG_MODULES
# By default, build modules as well
all: modules
# Build modules
PHONY += modules
modules: $(busybox-dirs) $(if $(KBUILD_BUILTIN),busybox)
@echo ' Building modules, stage 2.';
$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
# Target to prepare building external modules
PHONY += modules_prepare
modules_prepare: prepare scripts
# Target to install modules
PHONY += modules_install
modules_install: _modinst_ _modinst_post
PHONY += _modinst_
_modinst_:
@if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
echo "Warning: you may need to install module-init-tools"; \
echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
sleep 1; \
fi
@rm -rf $(MODLIB)/kernel
@rm -f $(MODLIB)/source
@mkdir -p $(MODLIB)/kernel
@ln -s $(srctree) $(MODLIB)/source
@if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
rm -f $(MODLIB)/build ; \
ln -s $(objtree) $(MODLIB)/build ; \
fi
$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
# If System.map exists, run depmod. This deliberately does not have a
# dependency on System.map since that would run the dependency tree on
# busybox. This depmod is only for convenience to give the initial
# boot a modules.dep even before / is mounted read-write. However the
# boot script depmod is the master version.
ifeq "$(strip $(INSTALL_MOD_PATH))" ""
depmod_opts :=
else
depmod_opts := -b $(INSTALL_MOD_PATH) -r
endif
PHONY += _modinst_post
_modinst_post: _modinst_
if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
else # CONFIG_MODULES
# Modules not configured
# ---------------------------------------------------------------------------
modules modules_install: FORCE
@echo
@echo "The present busybox configuration has modules disabled."
@echo "Type 'make config' and enable loadable module support."
@echo "Then build a kernel with module support enabled."
@echo
@exit 1
endif # CONFIG_MODULES
###
# Cleaning is done on three levels.
# make clean Delete most generated files
# Leave enough to build external modules
# make mrproper Delete the current configuration, and all generated files
# make distclean Remove editor backup files, patch leftover files and the like
# Directories & files removed with 'make clean'
CLEAN_DIRS += $(MODVERDIR) _install 0_lib
CLEAN_FILES += busybox busybox_unstripped* busybox.links \
System.map .kernelrelease \
.tmp_kallsyms* .tmp_version .tmp_busybox* .tmp_System.map
# Directories & files removed with 'make mrproper'
MRPROPER_DIRS += include/config include2
MRPROPER_FILES += .config .config.old include/asm .version .old_version \
include/NUM_APPLETS.h \
include/autoconf.h \
include/bbconfigopts.h \
include/bbconfigopts_bz2.h \
include/usage_compressed.h \
include/applet_tables.h \
include/applets.h \
include/usage.h \
applets/usage \
.kernelrelease Module.symvers tags TAGS cscope* \
busybox_old
# clean - Delete most, but leave enough to build external modules
#
clean: rm-dirs := $(CLEAN_DIRS)
clean: rm-files := $(CLEAN_FILES)
clean-dirs := $(addprefix _clean_,$(srctree) $(busybox-alldirs))
PHONY += $(clean-dirs) clean archclean
$(clean-dirs):
$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
clean: archclean $(clean-dirs)
$(call cmd,rmdirs)
$(call cmd,rmfiles)
@find . $(RCS_FIND_IGNORE) \
\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
-type f -print | xargs rm -f
PHONY += doc-clean
doc-clean: rm-files := docs/busybox.pod \
docs/BusyBox.html docs/busybox.1 docs/BusyBox.txt
doc-clean: