Hi Eugeniy, A couple of minor notes below.
> -----Original Message----- > From: Eugeniy Paltsev <eugeniy.palt...@synopsys.com> > Sent: Thursday, June 4, 2020 8:39 PM > To: linux-snps-...@lists.infradead.org; Vineet Gupta <vgu...@synopsys.com> > Cc: linux-kernel@vger.kernel.org; Alexey Brodkin <abrod...@synopsys.com>; > Eugeniy Paltsev > <palt...@synopsys.com> > Subject: [PATCH v2 1/4] ARC: allow to override default mcpu compiler flag > > Kernel builds set their own default -mcpu for a given ISA build. We used to use a default "-mcpu" per ARC ISA version (one for ARCompact and one for ARCv2). > But that gets in the way of "custom" -mcpu flags from propagating > into kernel build. But with more versions of CPUs & SoCs becoming available we want to be able to fine-tune generated code more precise. > This will also be used in next patches for HSDK-4xD board support which > uses a different -mcpu to effect dual issue scheduling. "...for utilization of the new CPU's dual-issue capabilities"? > +++ b/arch/arc/Makefile > @@ -10,8 +10,25 @@ CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- > arceb-linux-) > endif > > cflags-y += -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__ > -cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7 > -cflags-$(CONFIG_ISA_ARCV2) += -mcpu=hs38 > + > +tune-mcpu-def-$(CONFIG_ISA_ARCOMPACT) := -mA7 I'd suggest to either swap "-mA7" which is being obsoleted with "-mcpu=arc700" right here or as a separate change, otherwise we may soon get ATC700 builds broken with newer compilers. -Alexey
