xref: /openbmc/linux/Kbuild (revision a2818ee4)
1# SPDX-License-Identifier: GPL-2.0
2#
3# Kbuild for top-level directory of the kernel
4# This file takes care of the following:
5# 1) Generate bounds.h
6# 2) Generate timeconst.h
7# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
8# 4) Check for missing system calls
9# 5) Generate constants.py (may need bounds.h)
10
11#####
12# 1) Generate bounds.h
13
14bounds-file := include/generated/bounds.h
15
16always  := $(bounds-file)
17targets := kernel/bounds.s
18
19$(bounds-file): kernel/bounds.s FORCE
20	$(call filechk,offsets,__LINUX_BOUNDS_H__)
21
22#####
23# 2) Generate timeconst.h
24
25timeconst-file := include/generated/timeconst.h
26
27targets += $(timeconst-file)
28
29define filechk_gentimeconst
30	(echo $(CONFIG_HZ) | bc -q $< )
31endef
32
33$(timeconst-file): kernel/time/timeconst.bc FORCE
34	$(call filechk,gentimeconst)
35
36#####
37# 3) Generate asm-offsets.h
38#
39
40offsets-file := include/generated/asm-offsets.h
41
42always  += $(offsets-file)
43targets += arch/$(SRCARCH)/kernel/asm-offsets.s
44
45arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
46
47$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
48	$(call filechk,offsets,__ASM_OFFSETS_H__)
49
50#####
51# 4) Check for missing system calls
52#
53
54always += missing-syscalls
55targets += missing-syscalls
56
57quiet_cmd_syscalls = CALL    $<
58      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
59
60missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
61	$(call cmd,syscalls)
62
63#####
64# 5) Generate constants for Python GDB integration
65#
66
67extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py
68
69build_constants_py: $(timeconst-file) $(bounds-file)
70	@$(MAKE) $(build)=scripts/gdb/linux $@
71
72# Keep these three files during make clean
73no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
74