diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index da28e7ba6083..a36b5a8b123e 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -983,6 +983,18 @@ config HZ default AT91_TIMER_HZ if ARCH_AT91 default 100 +config THUMB2_KERNEL + bool "Compile the kernel in Thumb-2 mode" + depends on CPU_V7 && EXPERIMENTAL + select AEABI + select ARM_ASM_UNIFIED + help + By enabling this option, the kernel will be compiled in + Thumb-2 mode. A compiler/assembler that understand the unified + ARM-Thumb syntax is needed. + + If unsure, say N. + config ARM_ASM_UNIFIED bool diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index a89e4734b8f0..1a6f70e52921 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -8,6 +8,7 @@ source "lib/Kconfig.debug" # n, but then RMK will have to kill you ;). config FRAME_POINTER bool + depends on !THUMB2_KERNEL default y if !ARM_UNWIND help If you say N here, the resulting kernel will be slightly smaller and diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 3505572a21e6..e150f232458d 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -93,9 +93,16 @@ ifeq ($(CONFIG_ARM_UNWIND),y) CFLAGS_ABI +=-funwind-tables endif +ifeq ($(CONFIG_THUMB2_KERNEL),y) +AFLAGS_AUTOIT :=$(call as-option,-Wa$(comma)-mimplicit-it=thumb,-Wa$(comma)-mauto-it) +AFLAGS_NOWARN :=$(call as-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W) +CFLAGS_THUMB2 :=-mthumb $(AFLAGS_AUTOIT) $(AFLAGS_NOWARN) +AFLAGS_THUMB2 :=$(CFLAGS_THUMB2) -Wa$(comma)-mthumb +endif + # Need -Uarm for gcc < 3.x -KBUILD_CFLAGS +=$(CFLAGS_ABI) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm -KBUILD_AFLAGS +=$(CFLAGS_ABI) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float +KBUILD_CFLAGS +=$(CFLAGS_ABI) $(CFLAGS_THUMB2) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm +KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_THUMB2) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float CHECKFLAGS += -D__arm__