When building a THumb-1-only target with CONFIG_SYS_THUMB_BUILD, some files fail to build, most of the time because they include mcr instructions, which only exist for Thumb-2.
Thos patch introduces a Kconfig option CONFIG_THUMB2 and uses it to select between Thumb-2 and ARM mode for the aforementioned files.
Signed-off-by: Albert ARIBAUD albert.u.boot@aribaud.net --- This patch has been build-tested and run-tested on ED Mini V2, above the "edmini: switch to SPL" patch, and found to reduce U-Boot size by 25% and SPL size by 14%... and to run fine. :)
This patch has also been tested against side effects on the non-Thumb wireless_space target. The binaries produced with and without ths patch were found to differ only by their version string.
Changes in v2: - fixed a typo in the commit message - added file arch/arm/thumb1/include/asm/proc-armv/system.h, which overrides arch/arm/include/asm/proc-armv/system.h when building for Thumb-1 and provides non-functional but Thumb-compilable IRQ and FIQ related macros and functions.
Makefile | 2 + arch/arm/Kconfig | 4 ++ arch/arm/cpu/arm926ejs/Makefile | 11 ++++ arch/arm/lib/Makefile | 11 ++++ arch/arm/mach-orion5x/Makefile | 10 ++++ arch/arm/thumb1/include/asm/proc-armv/system.h | 69 ++++++++++++++++++++++++++ examples/standalone/Makefile | 10 ++++ include/configs/edminiv2.h | 4 +- 8 files changed, 120 insertions(+), 1 deletion(-) create mode 100644 arch/arm/thumb1/include/asm/proc-armv/system.h
diff --git a/Makefile b/Makefile index bd4abab..7dc9dc6 100644 --- a/Makefile +++ b/Makefile @@ -593,6 +593,8 @@ KBUILD_CFLAGS += $(KCFLAGS) UBOOTINCLUDE := \ -Iinclude \ $(if $(KBUILD_SRC), -I$(srctree)/include) \ + $(if $(CONFIG_SYS_THUMB_BUILD), $(if $(CONFIG_HAS_THUMB2),, \ + -I$(srctree)/arch/$(ARCH)/thumb1/include),) \ -I$(srctree)/arch/$(ARCH)/include \ -include $(srctree)/include/linux/kconfig.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 820ba1c..35420ca 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -10,6 +10,9 @@ config ARM64 config HAS_VBAR bool
+config HAS_THUMB2 + bool + config CPU_ARM720T bool
@@ -32,6 +35,7 @@ config CPU_ARM1176 config CPU_V7 bool select HAS_VBAR + select HAS_THUMB2
config CPU_PXA bool diff --git a/arch/arm/cpu/arm926ejs/Makefile b/arch/arm/cpu/arm926ejs/Makefile index f5944cc..090d64b 100644 --- a/arch/arm/cpu/arm926ejs/Makefile +++ b/arch/arm/cpu/arm926ejs/Makefile @@ -22,3 +22,14 @@ obj-$(CONFIG_MX27) += mx27/ obj-$(if $(filter mxs,$(SOC)),y) += mxs/ obj-$(CONFIG_PANTHEON) += pantheon/ obj-$(if $(filter spear,$(SOC)),y) += spear/ + +# some files can only build in ARM or THUMB2, not THUMB1 + +ifdef CONFIG_SYS_THUMB_BUILD +ifndef CONFIG_HAS_THUMB2 + +CFLAGS_cpu.o := -marm +CFLAGS_cache.o := -marm + +endif +endif diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile index da8ed72..a753bca 100644 --- a/arch/arm/lib/Makefile +++ b/arch/arm/lib/Makefile @@ -55,3 +55,14 @@ obj-$(CONFIG_DEBUG_LL) += debug.o ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS))) extra-y += eabi_compat.o endif + +# some files can only build in ARM or THUMB2, not THUMB1 + +ifdef CONFIG_SYS_THUMB_BUILD +ifndef CONFIG_HAS_THUMB2 + +CFLAGS_cache.o := -marm +CFLAGS_cache-cp15.o := -marm + +endif +endif diff --git a/arch/arm/mach-orion5x/Makefile b/arch/arm/mach-orion5x/Makefile index 546ebcb..33dcad4 100644 --- a/arch/arm/mach-orion5x/Makefile +++ b/arch/arm/mach-orion5x/Makefile @@ -16,3 +16,13 @@ obj-y += timer.o ifndef CONFIG_SKIP_LOWLEVEL_INIT obj-y += lowlevel_init.o endif + +# some files can only build in ARM or THUMB2, not THUMB1 + +ifdef CONFIG_SYS_THUMB_BUILD +ifndef CONFIG_HAS_THUMB2 + +CFLAGS_cpu.o := -marm + +endif +endif diff --git a/arch/arm/thumb1/include/asm/proc-armv/system.h b/arch/arm/thumb1/include/asm/proc-armv/system.h new file mode 100644 index 0000000..7dfbf3d --- /dev/null +++ b/arch/arm/thumb1/include/asm/proc-armv/system.h @@ -0,0 +1,69 @@ +/* + * Thumb-1 drop-in for the linux/include/asm-arm/proc-armv/system.h + * + * (C) Copyright 2015 + * Albert ARIBAUD albert.u.boot@aribaud.net + * + * The original file does not build in Thumb mode. However, in U-Boot + * we don't use interrupt context, so we can redefine these as empty + * memory barriers, which makes Thumb-1 compiler happy. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +/* + * Use the same macro name as linux/include/asm-arm/proc-armv/system.h + * here, so that if the original ever gets included after us, it won't + * try to re-redefine anything. + */ + +#ifndef __ASM_PROC_SYSTEM_H +#define __ASM_PROC_SYSTEM_H + +/* + * Redefine all original macros with static inline functions containing + * a simple memory barrier, so that they produce the same instruction + * ordering constraints as their original counterparts. + * We use static inline functions rather than macros so that we can tell + * the compiler to not complain about unused arguments. + */ + +static inline void local_irq_save( + unsigned long flags __attribute__((unused))) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void local_irq_enable(void) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void local_irq_disable(void) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void __stf(void) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void __clf(void) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void local_save_flags( + unsigned long flags __attribute__((unused))) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +static inline void local_irq_restore( + unsigned long flags __attribute__((unused))) +{ + __asm__ __volatile__ ("" : : : "memory"); +} + +#endif /* __ASM_PROC_SYSTEM_H */ diff --git a/examples/standalone/Makefile b/examples/standalone/Makefile index 0863a8c..5a6ae00 100644 --- a/examples/standalone/Makefile +++ b/examples/standalone/Makefile @@ -73,3 +73,13 @@ $(obj)/%.srec: $(obj)/% FORCE $(obj)/%.bin: OBJCOPYFLAGS := -O binary $(obj)/%.bin: $(obj)/% FORCE $(call if_changed,objcopy) + +# some files can only build in ARM or THUMB2, not THUMB1 + +ifdef CONFIG_SYS_THUMB_BUILD +ifndef CONFIG_HAS_THUMB2 + +CFLAGS_stubs.o := -marm + +endif +endif diff --git a/include/configs/edminiv2.h b/include/configs/edminiv2.h index 70a698a..112583b 100644 --- a/include/configs/edminiv2.h +++ b/include/configs/edminiv2.h @@ -12,6 +12,8 @@ #ifndef _CONFIG_EDMINIV2_H #define _CONFIG_EDMINIV2_H
+#define CONFIG_SYS_THUMB_BUILD + /* * Version number information */ @@ -203,7 +205,7 @@ /* * Size of malloc() pool */ -#define CONFIG_SYS_MALLOC_LEN (1024 * 256) /* 256kB for malloc() */ +#define CONFIG_SYS_MALLOC_LEN (1024 * 1024) /* 1MB for malloc() */
/* * Other required minimal configurations