Commit f772acf8 authored by Wolfgang Denk's avatar Wolfgang Denk

ARM: compiler options cleanup - improve tool chain support

For some time there have been repeated reports about build problems
with some ARM (cross) tool chains.  Especially issues about
(in)compatibility with the tool chain provided runtime support
library libgcc.a caused to add and support a private implementation
of such runtime support code in U-Boot.  A closer look at the code
indicated that some of these issues are actually home-made.  This
patch attempts to clean up some of the most obvious problems and make
building of U-Boot with different tool chains easier:

- Even though all ARM systems basicy used the same compiler options
  to select a specific ABI from the tool chain, the code for this was
  distributed over all cpu/*/config.mk files.  We move this one level
  up into lib_arm/config.mk instead.

- So far, we only checked if "-mapcs-32" was supported by the tool
  chain; if yes, this was used, if not, "-mabi=apcs-gnu" was
  selected, no matter if the tool chain actually understood this
  option.  There was no support for EABI conformant tool chains.
  This patch implements the following logic:

  1) If the tool chain supports
	"-mabi=aapcs-linux -mno-thumb-interwork"
     we use these options (EABI conformant tool chain).
  2) Otherwise, we check first if
	"-mapcs-32"
     is supported, and then check for
	"-mabi=apcs-gnu"
     If one test succeeds, we use the first found option.
  3) In case 2), we also test if "-mno-thumb-interwork", and use
     this if the test succeeds. [For "-mabi=aapcs-linux" we set
     "-mno-thumb-interwork" mandatorily.]

  This way we use a similar logic for the compile options as the
  Linux kernel does.

- Some EABI conformant tool chains cause external references to
  utility functions like raise(); such functions are provided in the
  new file lib_arm/eabi_compat.c

  Note that lib_arm/config.mk gets parsed several times, so we must
  make sure to add eabi_compat.o only once to the linker list.
Signed-off-by: default avatarWolfgang Denk <wd@denx.de>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Dirk Behme <dirk.behme@googlemail.com>
Cc: Magnus Lilja <lilja.magnus@gmail.com>
Cc: Tom Rix <Tom.Rix@windriver.com>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Acked-by: default avatarSergey Kubushyn <ksi@koi8.net>
Tested-by: default avatarMagnus Lilja <lilja.magnus@gmail.com>
Tested-by: default avatarAndrzej Wolski <awolski@poczta.fm>
Tested-by: default avatarGaye Abdoulaye Walsimou <walsimou@walsimou.com>
Tested-by: default avatarTom Rix <Tom.Rix@windriver.com>
Tested-by: default avatarJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
parent b9cce2c7
......@@ -86,7 +86,7 @@ ifdef ARCH
sinclude $(TOPDIR)/lib_$(ARCH)/config.mk # include architecture dependend rules
endif
ifdef CPU
sinclude $(TOPDIR)/cpu/$(CPU)/config.mk # include CPU specific rules
sinclude $(TOPDIR)/cpu/$(CPU)/config.mk # include CPU specific rules
endif
ifdef SOC
sinclude $(TOPDIR)/cpu/$(CPU)/$(SOC)/config.mk # include SoC specific rules
......
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv5
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv5t
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,5 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv5t
# Supply options according to compiler version
#
# =========================================================================
#PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -31,6 +31,4 @@ PLATFORM_CPPFLAGS += -march=armv4 -mtune=arm7tdmi
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv4
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv4
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv5te
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv5te
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv4
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,5 @@ PLATFORM_CPPFLAGS += -march=armv5
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,\
$(call cc-option,-malignment-traps,))
......@@ -297,13 +297,6 @@ int dram_init(void)
return 0;
}
/******************************************************************************
* Dummy function to handle errors for EABI incompatibility
*****************************************************************************/
void raise(void)
{
}
/******************************************************************************
* Dummy function to handle errors for EABI incompatibility
*****************************************************************************/
......
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv4
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -33,5 +33,4 @@ PLATFORM_CPPFLAGS += -mbig-endian -march=armv5te -mtune=strongarm1100
# Supply options according to compiler version
#
# =========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -30,6 +30,4 @@ PLATFORM_CPPFLAGS += -march=armv4
# Supply options according to compiler version
#
# ========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -31,6 +31,4 @@ PLATFORM_CPPFLAGS += -march=armv5te -mtune=xscale
# Supply options according to compiler version
#
# ========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -31,6 +31,4 @@ PLATFORM_CPPFLAGS += -march=armv4 -mtune=arm7tdmi -msoft-float
# Supply options according to compiler version
#
# ========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -31,6 +31,4 @@ PLATFORM_CPPFLAGS += -march=armv4 -mtune=strongarm1100
# Supply options according to compiler version
#
# ========================================================================
PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
PLATFORM_CPPFLAGS +=$(call cc-option,-mno-thumb-interwork,)
PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
......@@ -51,12 +51,21 @@ OBJS := $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
LGOBJS := $(addprefix $(obj),$(GLSOBJS)) \
$(addprefix $(obj),$(GLCOBJS))
# Always build libarm.a
TARGETS := $(LIB)
# Build private libgcc only when asked for
ifdef USE_PRIVATE_LIBGCC
all: $(LIB) $(LIBGCC)
else
all: $(LIB)
TARGETS += $(LIBGCC)
endif
# For EABI conformant tool chains, provide eabi_compat()
ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
TARGETS += $(obj)eabi_compat.o
endif
all: $(TARGETS)
$(LIB): $(obj).depend $(OBJS)
$(AR) $(ARFLAGS) $@ $(OBJS)
......
......@@ -25,4 +25,32 @@ CROSS_COMPILE ?= arm-linux-
PLATFORM_CPPFLAGS += -DCONFIG_ARM -D__ARM__
# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:
PLATFORM_CPPFLAGS += $(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
PLATFORM_CPPFLAGS += $(call cc-option,\
-mabi=aapcs-linux -mno-thumb-interwork,\
$(call cc-option,\
-mapcs-32,\
$(call cc-option,\
-mabi=apcs-gnu,\
)\
) $(call cc-option,-mno-thumb-interwork,)\
)
# For EABI, make sure to provide raise()
ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
# This file is parsed several times; make sure to add only once.
ifeq (,$(findstring lib_arm/eabi_compat.o,$(PLATFORM_LIBS)))
PLATFORM_LIBS += $(OBJTREE)/lib_arm/eabi_compat.o
endif
endif
LDSCRIPT := $(SRCTREE)/cpu/$(CPU)/u-boot.lds
/*
* Utility functions needed for (some) EABI conformant tool chains.
*
* (C) Copyright 2009 Wolfgang Denk <wd@denx.de>
*
* 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.
*/
#include <common.h>
int raise (int signum)
{
printf("raise: Signal # %d caught\n", signum);
return 0;
}
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