Hi Michal, Can u please take a look at patch below ! Thx, -Vineet On Friday 26 February 2016 01:59 PM, Vineet Gupta wrote: > ARC architecture has 2 instruction sets: ARCompact/ARCv2. > While same gcc supports compiling for either (using appropriate toggles), > we can't use the same toolchain to build kernel because libgcc needs > to be unique and the toolchian (uClibc based) is not multilibed. > > uClibc toolchain is convenient since it allows all userspace and > kernel to be built with a single install for an ISA. > > This however means 2 gnu installs (with same triplet prefix) are needed > for building for 2 ISA and need to be in PATH. > As developers we keep switching the builds, but would occassionally fail > to update the PATH leading to usage of wrong tools. And this would only > show up at the end of kernel build when linking incompatible libgcc. > > So the initial solution was to have gcc define a special preprocessor macro > DEFAULT_CPU_xxx which is unique for default toolchain configuration. > Claudiu proposed using grep for an existing preprocessor macro which is > again uniquely defined per ISA. > > Cc: Michal Marek <mmarek at suse.cz> > Suggested-by: Claudiu Zissulescu <claziss at synopsys.com> > Signed-off-by: Vineet Gupta <vgupta at synopsys.com> > --- > arch/arc/Makefile | 14 ++++++++++++++ > arch/arc/include/asm/arcregs.h | 6 ------ > 2 files changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/arc/Makefile b/arch/arc/Makefile > index c8230f3395f2..21682e047c00 100644 > --- a/arch/arc/Makefile > +++ b/arch/arc/Makefile > @@ -18,6 +18,20 @@ cflags-y += -fno-common -pipe -fno-builtin -D__linux__ > cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7 > cflags-$(CONFIG_ISA_ARCV2) += -mcpu=archs > > +is_700 = $(shell $(CC) -dM -E - < /dev/null | grep -q "ARC700" && echo 1 || echo 0) > + > +ifdef CONFIG_ISA_ARCOMPACT > +ifeq ($(is_700), 0) > + $(error Toolchain not configured for ARCompact builds) > +endif > +endif > + > +ifdef CONFIG_ISA_ARCV2 > +ifeq ($(is_700), 1) > + $(error Toolchain not configured for ARCv2 builds) > +endif > +endif > + > ifdef CONFIG_ARC_CURR_IN_REG > # For a global register defintion, make sure it gets passed to every file > # We had a customer reported bug where some code built in kernel was NOT using > diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h > index f9f4c6f59fdb..7fbaea00a336 100644 > --- a/arch/arc/include/asm/arcregs.h > +++ b/arch/arc/include/asm/arcregs.h > @@ -381,12 +381,6 @@ static inline int is_isa_arcompact(void) > return IS_ENABLED(CONFIG_ISA_ARCOMPACT); > } > > -#if defined(CONFIG_ISA_ARCOMPACT) && !defined(_CPU_DEFAULT_A7) > -#error "Toolchain not configured for ARCompact builds" > -#elif defined(CONFIG_ISA_ARCV2) && !defined(_CPU_DEFAULT_HS) > -#error "Toolchain not configured for ARCv2 builds" > -#endif > - > #endif /* __ASEMBLY__ */ > > #endif /* _ASM_ARC_ARCREGS_H */ >
