1# SPDX-License-Identifier: GPL-2.0 2# 3# Makefile for the linux kernel. 4# 5 6ccflags-y := -fno-function-sections -fno-data-sections 7 8obj-y := main.o version.o mounts.o 9ifneq ($(CONFIG_BLK_DEV_INITRD),y) 10obj-y += noinitramfs.o 11else 12obj-$(CONFIG_BLK_DEV_INITRD) += initramfs.o 13endif 14obj-$(CONFIG_GENERIC_CALIBRATE_DELAY) += calibrate.o 15obj-$(CONFIG_INITRAMFS_TEST) += initramfs_test.o 16 17obj-y += init_task.o 18 19mounts-y := do_mounts.o 20mounts-$(CONFIG_BLK_DEV_RAM) += do_mounts_rd.o 21mounts-$(CONFIG_BLK_DEV_INITRD) += do_mounts_initrd.o 22 23# 24# UTS_VERSION 25# 26 27smp-flag-$(CONFIG_SMP) := SMP 28preempt-flag-$(CONFIG_PREEMPT_BUILD) := PREEMPT 29preempt-flag-$(CONFIG_PREEMPT_DYNAMIC) := PREEMPT_DYNAMIC 30preempt-flag-$(CONFIG_PREEMPT_RT) := PREEMPT_RT 31 32build-version = $(or $(KBUILD_BUILD_VERSION), $(build-version-auto)) 33build-timestamp = $(or $(KBUILD_BUILD_TIMESTAMP), $(build-timestamp-auto)) 34 35# Maximum length of UTS_VERSION is 64 chars 36filechk_uts_version = \ 37 utsver=$$(echo '$(pound)'"$(build-version)" $(smp-flag-y) $(preempt-flag-y) "$(build-timestamp)" | cut -b -64); \ 38 echo '$(pound)'define UTS_VERSION \""$${utsver}"\" 39 40# 41# Build version.c with temporary UTS_VERSION 42# 43 44$(obj)/utsversion-tmp.h: FORCE 45 $(call filechk,uts_version) 46 47clean-files += utsversion-tmp.h 48 49$(obj)/version.o: $(obj)/utsversion-tmp.h 50CFLAGS_version.o := -include $(obj)/utsversion-tmp.h 51 52# 53# Build version-timestamp.c with final UTS_VERSION 54# 55 56include/generated/utsversion.h: build-version-auto = $(shell $(srctree)/scripts/build-version) 57include/generated/utsversion.h: build-timestamp-auto = $(shell LC_ALL=C date) 58include/generated/utsversion.h: FORCE 59 $(call filechk,uts_version) 60 61$(obj)/version-timestamp.o: include/generated/utsversion.h 62CFLAGS_version-timestamp.o := -include include/generated/utsversion.h 63