xref: /openbmc/linux/Kbuild (revision 4173cbac)
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 timeconst.h
6# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
7# 4) Check for missing system calls
8# 5) Generate constants.py (may need bounds.h)
9
10#####
11# 1) Generate bounds.h
12
13bounds-file := include/generated/bounds.h
14
15always  := $(bounds-file)
16targets := kernel/bounds.s
17
18# We use internal kbuild rules to avoid the "is up to date" message from make
19kernel/bounds.s: kernel/bounds.c FORCE
20	$(call if_changed_dep,cc_s_c)
21
22$(obj)/$(bounds-file): kernel/bounds.s FORCE
23	$(call filechk,offsets,__LINUX_BOUNDS_H__)
24
25#####
26# 2) Generate timeconst.h
27
28timeconst-file := include/generated/timeconst.h
29
30targets += $(timeconst-file)
31
32quiet_cmd_gentimeconst = GEN     $@
33define cmd_gentimeconst
34	(echo $(CONFIG_HZ) | bc -q $< ) > $@
35endef
36define filechk_gentimeconst
37	(echo $(CONFIG_HZ) | bc -q $< )
38endef
39
40$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
41	$(call filechk,gentimeconst)
42
43#####
44# 3) Generate asm-offsets.h
45#
46
47offsets-file := include/generated/asm-offsets.h
48
49always  += $(offsets-file)
50targets += arch/$(SRCARCH)/kernel/asm-offsets.s
51
52# We use internal kbuild rules to avoid the "is up to date" message from make
53arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
54                                      $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
55	$(call if_changed_dep,cc_s_c)
56
57$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
58	$(call filechk,offsets,__ASM_OFFSETS_H__)
59
60#####
61# 4) Check for missing system calls
62#
63
64always += missing-syscalls
65targets += missing-syscalls
66
67quiet_cmd_syscalls = CALL    $<
68      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
69
70missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
71	$(call cmd,syscalls)
72
73#####
74# 5) Generate constants for Python GDB integration
75#
76
77extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
78
79build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
80	@$(MAKE) $(build)=scripts/gdb/linux $@
81
82# Keep these three files during make clean
83no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
84