u-boot/arch/arm/config.mk
Wolfgang Denk cca4e4aec1 Reduce build times
U-Boot Makefiles contain a number of tests for compiler features etc.
which so far are executed again and again.  On some architectures
(especially ARM) this results in a large number of calls to gcc.

This patch makes sure to run such tests only once, thus largely
reducing the number of "execve" system calls.

Example: number of "execve" system calls for building the "P2020DS"
(Power Architecture) and "qong" (ARM) boards, measured as:
	-> strace -f -e trace=execve -o /tmp/foo ./MAKEALL <board>
	-> grep execve /tmp/foo | wc -l

	Before: After:	Reduction:
==================================
P2020DS 20555	15205	-26%
qong	31692	14490	-54%

As a result, built times are significantly reduced, typically by
30...50%.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Andy Fleming <afleming@gmail.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Albert Aribaud <albert.aribaud@free.fr>
cc: Graeme Russ <graeme.russ@gmail.com>
cc: Mike Frysinger <vapier@gentoo.org>
Tested-by: Graeme Russ <graeme.russ@gmail.com>
Tested-by: Matthias Weisser <weisserm@arcor.de>
Tested-by: Sanjeev Premi <premi@ti.com>
Tested-by: Simon Glass <sjg@chromium.org>
Tested-by: Macpaul Lin <macpaul@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2011-11-03 20:44:58 +01:00

84 lines
2.6 KiB
Makefile

#
# (C) Copyright 2000-2002
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# See file CREDITS for list of people who contributed to this
# project.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA 02111-1307 USA
#
CROSS_COMPILE ?= arm-linux-
ifndef CONFIG_STANDALONE_LOAD_ADDR
ifeq ($(SOC),omap3)
CONFIG_STANDALONE_LOAD_ADDR = 0x80300000
else
CONFIG_STANDALONE_LOAD_ADDR = 0xc100000
endif
endif
PLATFORM_CPPFLAGS += -DCONFIG_ARM -D__ARM__
# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:
PF_CPPFLAGS_ARM := $(call cc-option,-marm,)
# Try if EABI is supported, else fall back to old API,
# i. e. for example:
# - with ELDK 4.2 (EABI supported), use:
# -mabi=aapcs-linux -mno-thumb-interwork
# - with ELDK 4.1 (gcc 4.x, no EABI), use:
# -mabi=apcs-gnu -mno-thumb-interwork
# - with ELDK 3.1 (gcc 3.x), use:
# -mapcs-32 -mno-thumb-interwork
PF_CPPFLAGS_ABI := $(call cc-option,\
-mabi=aapcs-linux -mno-thumb-interwork,\
$(call cc-option,\
-mapcs-32,\
$(call cc-option,\
-mabi=apcs-gnu,\
)\
) $(call cc-option,-mno-thumb-interwork,)\
)
PLATFORM_CPPFLAGS += $(PF_CPPFLAGS_ARM) $(PF_CPPFLAGS_ABI)
# For EABI, make sure to provide raise()
ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
# This file is parsed many times, so the string may get added multiple
# times. Also, the prefix needs to be different based on whether
# CONFIG_SPL_BUILD is defined or not. 'filter-out' the existing entry
# before adding the correct one.
ifdef CONFIG_SPL_BUILD
PLATFORM_LIBS := $(SPLTREE)/arch/arm/lib/eabi_compat.o \
$(filter-out %/arch/arm/lib/eabi_compat.o, $(PLATFORM_LIBS))
else
PLATFORM_LIBS := $(OBJTREE)/arch/arm/lib/eabi_compat.o \
$(filter-out %/arch/arm/lib/eabi_compat.o, $(PLATFORM_LIBS))
endif
endif
ifdef CONFIG_SYS_LDSCRIPT
# need to strip off double quotes
LDSCRIPT := $(subst ",,$(CONFIG_SYS_LDSCRIPT))
else
LDSCRIPT := $(SRCTREE)/$(CPUDIR)/u-boot.lds
endif
# needed for relocation
ifndef CONFIG_NAND_SPL
LDFLAGS_u-boot += -pie
endif