xref: /openbmc/linux/Kbuild (revision e6c81cce) 
1#
2# Kbuild for top-level directory of the kernel
3# This file takes care of the following:
4# 1) Generate bounds.h
5# 2) Generate asm-offsets.h (may need bounds.h)
6# 3) Check for missing system calls
7
8# Default sed regexp - multiline due to syntax constraints
9define sed-y
10	"/^->/{s:->#\(.*\):/* \1 */:; \
11	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
12	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
13	s:->::; p;}"
14endef
15
16# Use filechk to avoid rebuilds when a header changes, but the resulting file
17# does not
18define filechk_offsets
19	(set -e; \
20	 echo "#ifndef $2"; \
21	 echo "#define $2"; \
22	 echo "/*"; \
23	 echo " * DO NOT MODIFY."; \
24	 echo " *"; \
25	 echo " * This file was generated by Kbuild"; \
26	 echo " */"; \
27	 echo ""; \
28	 sed -ne $(sed-y); \
29	 echo ""; \
30	 echo "#endif" )
31endef
32
33#####
34# 1) Generate bounds.h
35
36bounds-file := include/generated/bounds.h
37
38always  := $(bounds-file)
39targets := kernel/bounds.s
40
41# We use internal kbuild rules to avoid the "is up to date" message from make
42kernel/bounds.s: kernel/bounds.c FORCE
43	$(Q)mkdir -p $(dir $@)
44	$(call if_changed_dep,cc_s_c)
45
46$(obj)/$(bounds-file): kernel/bounds.s FORCE
47	$(call filechk,offsets,__LINUX_BOUNDS_H__)
48
49#####
50# 2) Generate asm-offsets.h
51#
52
53offsets-file := include/generated/asm-offsets.h
54
55always  += $(offsets-file)
56targets += arch/$(SRCARCH)/kernel/asm-offsets.s
57
58# We use internal kbuild rules to avoid the "is up to date" message from make
59arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
60                                      $(obj)/$(bounds-file) FORCE
61	$(Q)mkdir -p $(dir $@)
62	$(call if_changed_dep,cc_s_c)
63
64$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
65	$(call filechk,offsets,__ASM_OFFSETS_H__)
66
67#####
68# 3) Check for missing system calls
69#
70
71always += missing-syscalls
72targets += missing-syscalls
73
74quiet_cmd_syscalls = CALL    $<
75      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
76
77missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
78	$(call cmd,syscalls)
79
80# Keep these two files during make clean
81no-clean-files := $(bounds-file) $(offsets-file)
82