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-$(CONFIG_GENERIC_CALIBRATE_DELAY) += calibrate.o 15 16obj-y += init_task.o 17 18mounts-y := do_mounts.o 19mounts-$(CONFIG_BLK_DEV_RAM) += do_mounts_rd.o 20mounts-$(CONFIG_BLK_DEV_INITRD) += do_mounts_initrd.o 21 22# 23# UTS_VERSION 24# 25 26smp-flag-$(CONFIG_SMP) := SMP 27preempt-flag-$(CONFIG_PREEMPT_BUILD) := PREEMPT 28preempt-flag-$(CONFIG_PREEMPT_DYNAMIC) := PREEMPT_DYNAMIC 29preempt-flag-$(CONFIG_PREEMPT_RT) := PREEMPT_RT 30 31build-version = $(or $(KBUILD_BUILD_VERSION), $(build-version-auto)) 32build-timestamp = $(or $(KBUILD_BUILD_TIMESTAMP), $(build-timestamp-auto)) 33 34# Maximum length of UTS_VERSION is 64 chars 35filechk_uts_version = \ 36 utsver=$$(echo '$(pound)'"$(build-version)" $(smp-flag-y) $(preempt-flag-y) "$(build-timestamp)" | cut -b -64); \ 37 echo '$(pound)'define UTS_VERSION \""$${utsver}"\" 38 39# 40# Build version.c with temporary UTS_VERSION 41# 42 43$(obj)/utsversion-tmp.h: FORCE 44 $(call filechk,uts_version) 45 46clean-files += utsversion-tmp.h 47 48$(obj)/version.o: $(obj)/utsversion-tmp.h 49CFLAGS_version.o := -include $(obj)/utsversion-tmp.h 50 51# 52# Build version-timestamp.c with final UTS_VERSION 53# 54 55include/generated/utsversion.h: build-version-auto = $(shell $(src)/build-version) 56include/generated/utsversion.h: build-timestamp-auto = $(shell LC_ALL=C date) 57include/generated/utsversion.h: FORCE 58 $(call filechk,uts_version) 59 60$(obj)/version-timestamp.o: include/generated/utsversion.h 61CFLAGS_version-timestamp.o := -include include/generated/utsversion.h 62