linux/arch/arc/Makefile
Vineet Gupta cfdbc2e16e ARC: Build system: Makefiles, Kconfig, Linker script
Arnd in his review pointed out that arch Kconfig organisation has several
deficiencies:

* Build time entries for things which can be runtime extracted from DT
  (e.g. SDRAM size, core clk frequency..)
* Not multi-platform-image-build friendly (choice .. endchoice constructs)
* cpu variants support (750/770) is exclusive.

The first 2 have been fixed in subsequent patches.
Due to the nature of the 750 and 770, it is not possible to build for
both together, w/o special runtime glue code which would hurt
performance.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2013-02-11 20:00:25 +05:30

116 lines
3.4 KiB
Makefile

#
# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
UTS_MACHINE := arc
KBUILD_DEFCONFIG := fpga_defconfig
# For ARC FPGA Platforms
platform-$(CONFIG_ARC_PLAT_FPGA_LEGACY) := arcfpga
#New platform adds here
PLATFORM := $(platform-y)
export PLATFORM
cflags-y += -Iarch/arc/plat-$(PLATFORM)/include
cflags-y += -mA7 -fno-common -pipe -fno-builtin -D__linux__
atleast_gcc44 := $(call cc-ifversion, -gt, 0402, y)
cflags-$(atleast_gcc44) += -fsection-anchors
cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock
cflags-$(CONFIG_ARC_HAS_SWAPE) += -mswape
cflags-$(CONFIG_ARC_HAS_RTSC) += -mrtsc
cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables
ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
# Generic build system uses -O2, we want -O3
cflags-y += -O3
endif
# small data is default for elf32 tool-chain. If not usable, disable it
# This also allows repurposing GP as scratch reg to gcc reg allocator
disable_small_data := y
cflags-$(disable_small_data) += -mno-sdata -fcall-used-gp
cflags-$(CONFIG_CPU_BIG_ENDIAN) += -mbig-endian
ldflags-$(CONFIG_CPU_BIG_ENDIAN) += -EB
# STAR 9000518362:
# arc-linux-uclibc-ld (buildroot) or arceb-elf32-ld (EZChip) don't accept
# --build-id w/o "-marclinux".
# Default arc-elf32-ld is OK
ldflags-y += -marclinux
ARC_LIBGCC := -mA7
cflags-$(CONFIG_ARC_HAS_HW_MPY) += -multcost=16
ifndef CONFIG_ARC_HAS_HW_MPY
cflags-y += -mno-mpy
# newlib for ARC700 assumes MPY to be always present, which is generally true
# However, if someone really doesn't want MPY, we need to use the 600 ver
# which coupled with -mno-mpy will use mpy emulation
# With gcc 4.4.7, -mno-mpy is enough to make any other related adjustments,
# e.g. increased cost of MPY. With gcc 4.2.1 this had to be explicitly hinted
ARC_LIBGCC := -marc600
ifneq ($(atleast_gcc44),y)
cflags-y += -multcost=30
endif
endif
LIBGCC := $(shell $(CC) $(ARC_LIBGCC) $(cflags-y) --print-libgcc-file-name)
# Modules with short calls might break for calls into builtin-kernel
KBUILD_CFLAGS_MODULE += -mlong-calls
# Finally dump eveything into kernel build system
KBUILD_CFLAGS += $(cflags-y)
KBUILD_AFLAGS += $(KBUILD_CFLAGS)
LDFLAGS += $(ldflags-y)
# Needed for Linker script preprocessing
KBUILD_CPPFLAGS += -Iarch/arc/plat-$(PLATFORM)/include
head-y := arch/arc/kernel/head.o
# See arch/arc/Kbuild for content of core part of the kernel
core-y += arch/arc/
# w/o this ifneq, make ARCH=arc clean was crapping out
ifneq ($(platform-y),)
core-y += arch/arc/plat-$(PLATFORM)/
endif
libs-y += arch/arc/lib/ $(LIBGCC)
#default target for make without any arguements.
KBUILD_IMAGE := bootpImage
all: $(KBUILD_IMAGE)
boot := arch/arc/boot
bootpImage: vmlinux
uImage: vmlinux
$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
archclean:
$(Q)$(MAKE) $(clean)=$(boot)
# Hacks to enable final link due to absence of link-time branch relexation
# and gcc choosing optimal(shorter) branches at -O3
#
# vineetg Feb 2010: -mlong-calls switched off for overall kernel build
# However lib/decompress_inflate.o (.init.text) calls
# zlib_inflate_workspacesize (.text) causing relocation errors.
# Thus forcing all exten calls in this file to be long calls
export CFLAGS_decompress_inflate.o = -mmedium-calls
export CFLAGS_initramfs.o = -mmedium-calls