from https://raw.githubusercontent.com/schnitzeltony/meta-gumstix-community/master/recipes-bsp/u-boot/u-boot-overo/0013-arm-Switch-to-mno-unaligned-access-when-supported-by.patch

--- a/arch/arm/cpu/armv7/config.mk	2015-11-22 20:44:42.744557427 +0100
+++ b/arch/arm/cpu/armv7/config.mk	2015-11-22 20:45:26.381024395 +0100
@@ -18,9 +18,12 @@ PLATFORM_CPPFLAGS += $(PF_CPPFLAGS_ARMV7
 PF_RELFLAGS_SLB_AT := $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
 PLATFORM_RELFLAGS += $(PF_RELFLAGS_SLB_AT)
 
-# SEE README.arm-unaligned-accesses
+# On supported platforms we set the bit which causes us to trap on unaligned
+# memory access.  This is the opposite of what the compiler expects to be
+# the default so we must pass in -mno-unaligned-access so that it is aware
+# of our decision.
 PF_NO_UNALIGNED := $(call cc-option, -mno-unaligned-access,)
-PLATFORM_NO_UNALIGNED := $(PF_NO_UNALIGNED)
+PLATFORM_CPPFLAGS += $(PF_NO_UNALIGNED)
 
 ifneq ($(CONFIG_IMX_CONFIG),)
 ifdef CONFIG_SPL
