linux/arch/m68k/Makefile
Masahiro Yamada 2367b02642 m68k: Optimize cc-option calls for cpuflags-y
arch/m68k/Makefile computes lots of unneeded cc-option calls.

For example, if CONFIG_M5441x is not defined, there is not point in
evaluating the following compiler flag.

 cpuflags-$(CONFIG_M5441x)      := $(call cc-option,-mcpu=54455,-mcfv4e)

The result is set to cpuflags-, then thrown away.

The right hand side of ':=' is immediately expanded. Hence, all of the
16 calls for cc-option are evaluated. This is expensive since cc-option
invokes the compiler. This occurs even if you are not attempting to
build anything, like 'make ARCH=m68k help'.

Use '=' to expand the value _lazily_. The evaluation for cc-option is
delayed until $(cpuflags-y) is expanded. So, the cc-option test happens
just once at most.

This commit mimics tune-y of arch/arm/Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/20200526123810.301667-3-masahiroy@kernel.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2020-07-13 11:39:13 +02:00

150 lines
4.5 KiB
Makefile

#
# m68k/Makefile
#
# This file is included by the global makefile so that you can add your own
# architecture-specific flags and dependencies. Remember to do have actions
# for "archclean" and "archdep" for cleaning up and making dependencies for
# this architecture
#
# This file is subject to the terms and conditions of the GNU General Public
# License. See the file "COPYING" in the main directory of this archive
# for more details.
#
# Copyright (C) 1994 by Hamish Macdonald
# Copyright (C) 2002,2011 Greg Ungerer <gerg@snapgear.com>
#
KBUILD_DEFCONFIG := multi_defconfig
ifneq ($(SUBARCH),$(ARCH))
ifeq ($(CROSS_COMPILE),)
CROSS_COMPILE := $(call cc-cross-prefix, \
m68k-linux-gnu- m68k-linux- m68k-unknown-linux-gnu-)
endif
endif
#
# Enable processor type. Ordering of these is important - we want to
# use the minimum processor type of the range we support. The logic
# for 680x0 will only allow use of the -m68060 or -m68040 if no other
# 680x0 type is specified - and no option is specified for 68030 or
# 68020. The other m68k/ColdFire types always specify some type of
# compiler cpu type flag.
#
ifndef CONFIG_M68040
cpuflags-$(CONFIG_M68060) = -m68060
endif
ifndef CONFIG_M68060
cpuflags-$(CONFIG_M68040) = -m68040
endif
cpuflags-$(CONFIG_M68030) =
cpuflags-$(CONFIG_M68020) =
cpuflags-$(CONFIG_M68000) = -m68000
cpuflags-$(CONFIG_M5441x) = $(call cc-option,-mcpu=54455,-mcfv4e)
cpuflags-$(CONFIG_M54xx) = $(call cc-option,-mcpu=5475,-m5200)
cpuflags-$(CONFIG_M5407) = $(call cc-option,-mcpu=5407,-m5200)
cpuflags-$(CONFIG_M532x) = $(call cc-option,-mcpu=532x,-m5307)
cpuflags-$(CONFIG_M537x) = $(call cc-option,-mcpu=537x,-m5307)
cpuflags-$(CONFIG_M5307) = $(call cc-option,-mcpu=5307,-m5200)
cpuflags-$(CONFIG_M528x) = $(call cc-option,-mcpu=528x,-m5307)
cpuflags-$(CONFIG_M5275) = $(call cc-option,-mcpu=5275,-m5307)
cpuflags-$(CONFIG_M5272) = $(call cc-option,-mcpu=5272,-m5307)
cpuflags-$(CONFIG_M5271) = $(call cc-option,-mcpu=5271,-m5307)
cpuflags-$(CONFIG_M523x) = $(call cc-option,-mcpu=523x,-m5307)
cpuflags-$(CONFIG_M525x) = $(call cc-option,-mcpu=5253,-m5200)
cpuflags-$(CONFIG_M5249) = $(call cc-option,-mcpu=5249,-m5200)
cpuflags-$(CONFIG_M520x) = $(call cc-option,-mcpu=5208,-m5200)
cpuflags-$(CONFIG_M5206e) = $(call cc-option,-mcpu=5206e,-m5200)
cpuflags-$(CONFIG_M5206) = $(call cc-option,-mcpu=5206,-m5200)
# Evaluate tune cc-option calls now
cpuflags-y := $(cpuflags-y)
KBUILD_AFLAGS += $(cpuflags-y)
KBUILD_CFLAGS += $(cpuflags-y)
KBUILD_CFLAGS += -pipe -ffreestanding
ifdef CONFIG_MMU
# without -fno-strength-reduce the 53c7xx.c driver fails ;-(
KBUILD_CFLAGS += -fno-strength-reduce -ffixed-a2
else
# we can use a m68k-linux-gcc toolchain with these in place
KBUILD_CFLAGS += -DUTS_SYSNAME=\"uClinux\"
KBUILD_CFLAGS += -D__uClinux__
KBUILD_AFLAGS += -D__uClinux__
endif
KBUILD_LDFLAGS := -m m68kelf
KBUILD_LDS_MODULE += $(srctree)/arch/m68k/kernel/module.lds
ifdef CONFIG_SUN3
LDFLAGS_vmlinux = -N
endif
CHECKFLAGS += -D__mc68000__
ifdef CONFIG_KGDB
# If configured for kgdb support, include debugging infos and keep the
# frame pointer
KBUILD_CFLAGS := $(subst -fomit-frame-pointer,,$(KBUILD_CFLAGS)) -g
endif
#
# Select the assembler head startup code. Order is important. The default
# head code is first, processor specific selections can override it after.
#
head-y := arch/m68k/kernel/head.o
head-$(CONFIG_SUN3) := arch/m68k/kernel/sun3-head.o
head-$(CONFIG_M68000) := arch/m68k/68000/head.o
head-$(CONFIG_COLDFIRE) := arch/m68k/coldfire/head.o
core-y += arch/m68k/
libs-y += arch/m68k/lib/
all: zImage
lilo: vmlinux
if [ -f $(INSTALL_PATH)/vmlinux ]; then mv -f $(INSTALL_PATH)/vmlinux $(INSTALL_PATH)/vmlinux.old; fi
if [ -f $(INSTALL_PATH)/System.map ]; then mv -f $(INSTALL_PATH)/System.map $(INSTALL_PATH)/System.old; fi
cat vmlinux > $(INSTALL_PATH)/vmlinux
cp System.map $(INSTALL_PATH)/System.map
if [ -x /sbin/lilo ]; then /sbin/lilo; else /etc/lilo/install; fi
zImage compressed: vmlinux.gz
vmlinux.gz: vmlinux
ifndef CONFIG_KGDB
cp vmlinux vmlinux.tmp
$(STRIP) vmlinux.tmp
$(KGZIP) -9c vmlinux.tmp >vmlinux.gz
rm vmlinux.tmp
else
$(KGZIP) -9c vmlinux >vmlinux.gz
endif
bzImage: vmlinux.bz2
vmlinux.bz2: vmlinux
ifndef CONFIG_KGDB
cp vmlinux vmlinux.tmp
$(STRIP) vmlinux.tmp
$(KBZIP2) -1c vmlinux.tmp >vmlinux.bz2
rm vmlinux.tmp
else
$(KBZIP2) -1c vmlinux >vmlinux.bz2
endif
archclean:
rm -f vmlinux.gz vmlinux.bz2
archheaders:
$(Q)$(MAKE) $(build)=arch/m68k/kernel/syscalls all
install:
sh $(srctree)/arch/m68k/install.sh $(KERNELRELEASE) vmlinux.gz System.map "$(INSTALL_PATH)"