Form reading ARM architecture related documentation if appears that while unaligned memory access is supported by the processor in general it is not supported if MMU is disabled. The problem in question can be easilty reproduced by building the code without this patch, MMU disabled and trying to run 'memtest' command. Which would in turn call mem_test() which would eventually call show_progress(). That last function, if build without -mno-unaligned-access would result in unaligned memory access which would result in Barebox hanging. This patch is a very conservative attempt to make sure that any code that can potentially be executed with MMU disabled is built with unaligned memory accesses disabled. Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx> --- arch/arm/Makefile | 14 ++++++++++++++ scripts/Makefile.build | 2 +- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 721aa9b..9af4f3b 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -13,6 +13,20 @@ AS += -EL LD += -EL endif +# +# Unaligned access is not supported when MMU is disabled, so if MMU is +# enabled early on, only PBL, part of which will be executed with MMU +# diabled, would have to be build with -mno-unaligned-accesses, +# otherwise set this flag globally +# +ifeq ($(CONFIG_MMU_EARLY),y) +ifneq ($(CONFIG_PBL_IMAGE),y) +PBL_CFLAGS += -mno-unaligned-access +endif +else +CFLAGS += -mno-unaligned-access +endif + # This selects which instruction set is used. # Note that GCC does not numerically define an architecture version # macro, but instead defines a whole series of macros which makes diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 56ee072..1624a7a 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -188,7 +188,7 @@ quiet_cmd_pbl_cc_o_c = PBLCC $@ ifndef CONFIG_MODVERSIONS cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< -cmd_pbl_cc_o_c = $(CC) -D__PBL__ $(c_flags) $(PBL_CPPFLAGS) -c -o $@ $< +cmd_pbl_cc_o_c = $(CC) -D__PBL__ $(c_flags) $(PBL_CFLAGS) $(PBL_CPPFLAGS) -c -o $@ $< else # When module versioning is enabled the following steps are executed: -- 2.1.4 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
