| Message ID | 1424786016-12976-1-git-send-email-albert.u.boot@aribaud.net |
|---|---|
| State | Changes Requested |
| Delegated to: | Albert ARIBAUD |
| Headers | show |
On Tue, 24 Feb 2015 14:53:36 +0100, Albert ARIBAUD <albert.u.boot@aribaud.net> wrote: > When building a THumb-1-only target with CONFIG_SYS_THUMB_BUILD, > - fixed a typo in the commit message Drat. :/ If that version gets accepted, whoever commits it please s/THumb/Thumb/. Amicalement,
Hello Albert, On Tue, 24 Feb 2015 14:53:36 +0100, Albert ARIBAUD <albert.u.boot@aribaud.net> wrote: > 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. Ok, this does not fare as good as I have hoped, because there are also thumb1-unfrendly macros in arch/arm/include/asm/cache.h, this time with mcr and mrc instructions. /me hates macros used as inline functions. :( I cannot just replace the macros with empty inline functions as I did with arch/arm/include/asm/proc-armv/system.h, since this would cause cache to not work. :( This leaves only one solution: when buildding for thumb1, replace the macros in cache.h with plain function prototypes, and provide simple ARM-state implementations for these. We'll lose a bit of performance as instead of a single mcr or mrc instruction, we'll have a call switching from Thumb to ARM state, the mcr/mrc instruction, and a return to Thumb state. Hopefully that won't hurt performance too much. V3 in the works. Amicalement,
Hi Albert, On 25.02.2015 23:09, Albert ARIBAUD wrote: > On Tue, 24 Feb 2015 14:53:36 +0100, Albert ARIBAUD > <albert.u.boot@aribaud.net> wrote: >> 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. > > Ok, this does not fare as good as I have hoped, because there are also > thumb1-unfrendly macros in arch/arm/include/asm/cache.h, this time with > mcr and mrc instructions. > > /me hates macros used as inline functions. :( > > I cannot just replace the macros with empty inline functions as I did > with arch/arm/include/asm/proc-armv/system.h, since this would cause > cache to not work. :( > > This leaves only one solution: when buildding for thumb1, replace the > macros in cache.h with plain function prototypes, and provide simple > ARM-state implementations for these. We'll lose a bit of performance as > instead of a single mcr or mrc instruction, we'll have a call switching > from Thumb to ARM state, the mcr/mrc instruction, and a return to Thumb > state. Hopefully that won't hurt performance too much. > > V3 in the works. Any update on this? Thanks, Stefan
Hello Stefan, On Thu, 09 Apr 2015 11:22:27 +0200, Stefan Roese <sr@denx.de> wrote: > Hi Albert, > > On 25.02.2015 23:09, Albert ARIBAUD wrote: > > On Tue, 24 Feb 2015 14:53:36 +0100, Albert ARIBAUD > > <albert.u.boot@aribaud.net> wrote: > >> 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. > > > > Ok, this does not fare as good as I have hoped, because there are also > > thumb1-unfrendly macros in arch/arm/include/asm/cache.h, this time with > > mcr and mrc instructions. > > > > /me hates macros used as inline functions. :( > > > > I cannot just replace the macros with empty inline functions as I did > > with arch/arm/include/asm/proc-armv/system.h, since this would cause > > cache to not work. :( > > > > This leaves only one solution: when buildding for thumb1, replace the > > macros in cache.h with plain function prototypes, and provide simple > > ARM-state implementations for these. We'll lose a bit of performance as > > instead of a single mcr or mrc instruction, we'll have a call switching > > from Thumb to ARM state, the mcr/mrc instruction, and a return to Thumb > > state. Hopefully that won't hurt performance too much. > > > > V3 in the works. > > Any update on this? I am just restarting on this right now. > Thanks, > Stefan Amicalement,
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
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