| Message ID | 1328528248-20872-2-git-send-email-aneesh@ti.com |
|---|---|
| State | RFC |
| Delegated to: | Tom Rini |
| Headers | show |
On Mon, Feb 6, 2012 at 4:37 AM, Aneesh V <aneesh@ti.com> wrote: > Enable Thumb build and ARM-Thumb interworking based on the new > config flag CONFIG_SYS_THUMB_BUILD > > Signed-off-by: Aneesh V <aneesh@ti.com> [snip] > -# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb: > -PF_CPPFLAGS_ARM := $(call cc-option,-marm,) > +# Choose between ARM/Thumb instruction sets > +ifeq ($(CONFIG_SYS_THUMB_BUILD),y) > +PF_CPPFLAGS_ARM += $(call cc-option, -mthumb -mthumb-interwork, \ > + -marm -mno-thumb-interwork) > +else > +PF_CPPFLAGS_ARM += $(call cc-option, -marm -mno-thumb-interwork) > +endif We need the ':=' syntax to evaluate this once rather than for every file we build. Same with the rest of the changes here.
On Tuesday 07 February 2012 12:15 AM, Tom Rini wrote: > On Mon, Feb 6, 2012 at 4:37 AM, Aneesh V<aneesh@ti.com> wrote: >> Enable Thumb build and ARM-Thumb interworking based on the new >> config flag CONFIG_SYS_THUMB_BUILD >> >> Signed-off-by: Aneesh V<aneesh@ti.com> > [snip] >> -# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb: >> -PF_CPPFLAGS_ARM := $(call cc-option,-marm,) >> +# Choose between ARM/Thumb instruction sets >> +ifeq ($(CONFIG_SYS_THUMB_BUILD),y) >> +PF_CPPFLAGS_ARM += $(call cc-option, -mthumb -mthumb-interwork, \ >> + -marm -mno-thumb-interwork) >> +else >> +PF_CPPFLAGS_ARM += $(call cc-option, -marm -mno-thumb-interwork) >> +endif > > We need the ':=' syntax to evaluate this once rather than for every > file we build. Same with the rest of the changes here. > Oops! In my initial patch it was affecting PLATFORM_CPPFLAGS. When I rebased it I didn't notice that PF_CPPFLAGS_ARM was defined for the first time here. I will fix it. Thanks, Aneesh
diff --git a/README b/README index 9d713e8..dfe7fb3 100644 --- a/README +++ b/README @@ -420,6 +420,15 @@ The following options need to be configured: XWAY SoCs for booting from NOR flash. The U-Boot image needs to be swapped if a flash programmer is used. +- ARM Options: + CONFIG_SYS_THUMB_BUILD + + Use this flag to build U-Boot using the Thumb instruction + set for ARM architectures. Thumb instruction set provides + better code density. For ARM architectures that support + Thumb2 this flag will result in Thumb2 code generated by + GCC. + - Linux Kernel Interface: CONFIG_CLOCKS_IN_MHZ diff --git a/arch/arm/config.mk b/arch/arm/config.mk index 45f9dca..9a450d7 100644 --- a/arch/arm/config.mk +++ b/arch/arm/config.mk @@ -33,26 +33,31 @@ endif PLATFORM_CPPFLAGS += -DCONFIG_ARM -D__ARM__ -# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb: -PF_CPPFLAGS_ARM := $(call cc-option,-marm,) +# Choose between ARM/Thumb instruction sets +ifeq ($(CONFIG_SYS_THUMB_BUILD),y) +PF_CPPFLAGS_ARM += $(call cc-option, -mthumb -mthumb-interwork, \ + -marm -mno-thumb-interwork) +else +PF_CPPFLAGS_ARM += $(call cc-option, -marm -mno-thumb-interwork) +endif # 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 +# -mabi=aapcs-linux # - with ELDK 4.1 (gcc 4.x, no EABI), use: -# -mabi=apcs-gnu -mno-thumb-interwork +# -mabi=apcs-gnu # - 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,\ +# -mapcs-32 +PLATFORM_CPPFLAGS += $(call cc-option,\ + -mabi=aapcs-linux,\ $(call cc-option,\ - -mabi=apcs-gnu,\ + -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()
Enable Thumb build and ARM-Thumb interworking based on the new config flag CONFIG_SYS_THUMB_BUILD Signed-off-by: Aneesh V <aneesh@ti.com> --- README | 9 +++++++++ arch/arm/config.mk | 29 +++++++++++++++++------------ 2 files changed, 26 insertions(+), 12 deletions(-)