--- zzzz-none-000/linux-3.10.107/arch/arc/Makefile	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arc/Makefile	2021-02-04 17:41:59.000000000 +0000
@@ -9,35 +9,68 @@
 UTS_MACHINE := arc
 
 ifeq ($(CROSS_COMPILE),)
-CROSS_COMPILE := arc-elf32-
+CROSS_COMPILE := arc-linux-
 endif
 
-KBUILD_DEFCONFIG := fpga_defconfig
+KBUILD_DEFCONFIG := nsim_700_defconfig
 
-cflags-y	+= -mA7 -fno-common -pipe -fno-builtin -D__linux__
+cflags-y	+= -fno-common -pipe -fno-builtin -D__linux__
+cflags-$(CONFIG_ISA_ARCOMPACT)	+= -mA7
+cflags-$(CONFIG_ISA_ARCV2)	+= -mcpu=archs
 
-LINUXINCLUDE	+=  -include ${src}/arch/arc/include/asm/defines.h
+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
 # any kernel headers, and missing the r25 global register
-# Can't do unconditionally (like above) because of recursive include issues
+# Can't do unconditionally because of recursive include issues
 # due to <linux/thread_info.h>
 LINUXINCLUDE	+=  -include ${src}/arch/arc/include/asm/current.h
 endif
 
-atleast_gcc44 :=  $(call cc-ifversion, -gt, 0402, y)
+upto_gcc44    :=  $(call cc-ifversion, -le, 0404, y)
+atleast_gcc44 :=  $(call cc-ifversion, -ge, 0404, y)
+atleast_gcc48 :=  $(call cc-ifversion, -ge, 0408, y)
+
 cflags-$(atleast_gcc44)			+= -fsection-anchors
 
 cflags-$(CONFIG_ARC_HAS_LLSC)		+= -mlock
 cflags-$(CONFIG_ARC_HAS_SWAPE)		+= -mswape
-cflags-$(CONFIG_ARC_HAS_RTSC)		+= -mrtsc
-cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -fasynchronous-unwind-tables
+
+ifdef CONFIG_ISA_ARCV2
+
+ifndef CONFIG_ARC_HAS_LL64
+cflags-y				+= -mno-ll64
+endif
+
+ifndef CONFIG_ARC_HAS_DIV_REM
+cflags-y				+= -mno-div-rem
+endif
+
+endif
+
+# By default gcc 4.8 generates dwarf4 which kernel unwinder can't grok
+ifeq ($(atleast_gcc48),y)
+cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -gdwarf-2
+endif
 
 ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
 # Generic build system uses -O2, we want -O3
-cflags-y  += -O3
+# Note: No need to add to cflags-y as that happens anyways
+ARCH_CFLAGS += -O3
 endif
 
 # small data is default for elf32 tool-chain. If not usable, disable it
@@ -48,34 +81,19 @@
 cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= -mbig-endian
 ldflags-$(CONFIG_CPU_BIG_ENDIAN)	+= -EB
 
-# STAR 9000518362:
+# STAR 9000518362: (fixed with binutils shipping with gcc 4.8)
 # arc-linux-uclibc-ld (buildroot) or arceb-elf32-ld (EZChip) don't accept
-# --build-id w/o "-marclinux".
-# Default arc-elf32-ld is OK
-ldflags-y				+= -marclinux
-
-ARC_LIBGCC				:= -mA7
-cflags-$(CONFIG_ARC_HAS_HW_MPY)		+= -multcost=16
+# --build-id w/o "-marclinux". Default arc-elf32-ld is OK
+ldflags-$(upto_gcc44)			+= -marclinux
 
 ifndef CONFIG_ARC_HAS_HW_MPY
 	cflags-y	+= -mno-mpy
-
-# newlib for ARC700 assumes MPY to be always present, which is generally true
-# However, if someone really doesn't want MPY, we need to use the 600 ver
-# which coupled with -mno-mpy will use mpy emulation
-# With gcc 4.4.7, -mno-mpy is enough to make any other related adjustments,
-# e.g. increased cost of MPY. With gcc 4.2.1 this had to be explicitly hinted
-
-	ARC_LIBGCC		:= -marc600
-	ifneq ($(atleast_gcc44),y)
-		cflags-y	+= -multcost=30
-	endif
 endif
 
-LIBGCC	:= $(shell $(CC) $(ARC_LIBGCC) $(cflags-y) --print-libgcc-file-name)
+LIBGCC	:= $(shell $(CC) $(cflags-y) --print-libgcc-file-name)
 
 # Modules with short calls might break for calls into builtin-kernel
-KBUILD_CFLAGS_MODULE	+= -mlong-calls
+KBUILD_CFLAGS_MODULE	+= -mlong-calls -mno-millicode
 
 # Finally dump eveything into kernel build system
 KBUILD_CFLAGS	+= $(cflags-y)
@@ -90,8 +108,9 @@
 # w/o this dtb won't embed into kernel binary
 core-y		+= arch/arc/boot/dts/
 
-core-$(CONFIG_ARC_PLAT_FPGA_LEGACY)	+= arch/arc/plat-arcfpga/
-core-$(CONFIG_ARC_PLAT_TB10X)		+= arch/arc/plat-tb10x/
+core-$(CONFIG_ARC_PLAT_SIM)	+= arch/arc/plat-sim/
+core-$(CONFIG_ARC_PLAT_TB10X)	+= arch/arc/plat-tb10x/
+core-$(CONFIG_ARC_PLAT_AXS10X)	+= arch/arc/plat-axs10x/
 
 drivers-$(CONFIG_OPROFILE)	+= arch/arc/oprofile/
 
@@ -114,7 +133,7 @@
 	$(Q)$(MAKE) $(build)=$(boot)/dts $(boot)/dts/$@
 
 dtbs: scripts
-	$(Q)$(MAKE) $(build)=$(boot)/dts dtbs
+	$(Q)$(MAKE) $(build)=$(boot)/dts
 
 archclean:
 	$(Q)$(MAKE) $(clean)=$(boot)