ARC: rework setting of ARC CPU specific compiler options

It's a very rare if at all existing occasion when ARC CPU template
is used as is w/o any changes - in the end it's a beauty and competitive
advantage of ARC cores to be tailored for a particular use-case - and
so it doesn't make a lot of sense to offer template-based "-mcpu" selection.
Given for each and every platform we end-up adding quite a few more flags
it's logical to move "-mcpu" selection to platform's definition as well
which we exactly do here.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

arch/arc/config.mk

@@ -22,26 +22,6 @@ ifdef CONFIG_ARC_MMU_VER
 CONFIG_MMU = 1
 endif
 
-ifdef CONFIG_CPU_ARC750D
-PLATFORM_CPPFLAGS += -mcpu=arc700
-endif
-
-ifdef CONFIG_CPU_ARC770D
-PLATFORM_CPPFLAGS += -mcpu=arc700 -mlock -mswape
-endif
-
-ifdef CONFIG_CPU_ARCEM6
-PLATFORM_CPPFLAGS += -mcpu=arcem
-endif
-
-ifdef CONFIG_CPU_ARCHS34
-PLATFORM_CPPFLAGS += -mcpu=archs
-endif
-
-ifdef CONFIG_CPU_ARCHS38
-PLATFORM_CPPFLAGS += -mcpu=archs
-endif
-
 PLATFORM_CPPFLAGS += -ffixed-r25 -D__ARC__ -gdwarf-2 -mno-sdata
 PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections -fno-common
 

board/abilis/tb100/config.mk

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (C) 2020 Synopsys, Inc. All rights reserved.
+
+PLATFORM_CPPFLAGS += -mcpu=arc700 -mlock -mswape

board/synopsys/axs10x/config.mk

@@ -2,6 +2,12 @@
 #
 # Copyright (C) 2018 Synopsys, Inc. All rights reserved.
 
+ifdef CONFIG_TARGET_AXS103
+  PLATFORM_CPPFLAGS += -mcpu=archs
+else
+  PLATFORM_CPPFLAGS += -mcpu=arc700 -mlock -mswape
+endif
+
 bsp-generate: u-boot u-boot.bin
 ifdef CONFIG_ISA_ARCV2
 	$(Q)python3 $(srctree)/board/$(BOARDDIR)/headerize-axs.py \

board/synopsys/emsdp/config.mk

@@ -1,2 +1,2 @@
-PLATFORM_CPPFLAGS += -mlittle-endian -mnorm -mswap -mmpy-option=3 \
+PLATFORM_CPPFLAGS += -mcpu=arcem -mlittle-endian -mnorm -mswap -mmpy-option=3 \
                      -mbarrel-shifter -mfpu=fpuda_all -mcode-density

board/synopsys/hsdk/config.mk

@@ -2,6 +2,10 @@
 #
 # Copyright (C) 2018 Synopsys, Inc. All rights reserved.
 
+PLATFORM_CPPFLAGS += -mcpu=hs38_linux -mlittle-endian -matomic -mll64 \
+                     -mdiv-rem -mswap -mnorm -mmpy-option=9 -mbarrel-shifter \
+                     -mfpu=fpud_all
+
 bsp-generate: u-boot u-boot.bin
 	$(Q)python3 $(srctree)/board/$(BOARDDIR)/headerize-hsdk.py \
 		--arc-id 0x52 --image $(srctree)/u-boot.bin \

board/synopsys/iot_devkit/config.mk

@@ -1,2 +1,3 @@
-PLATFORM_CPPFLAGS += -mlittle-endian -mcode-density -mdiv-rem -mswap -mnorm -mmpy-option=6 -mbarrel-shifter
+PLATFORM_CPPFLAGS += -mcpu=arcem -mlittle-endian -mcode-density -mdiv-rem \
+                     -mswap -mnorm -mmpy-option=6 -mbarrel-shifter
 LDSCRIPT = $(srctree)/board/synopsys/iot_devkit/u-boot.lds

board/synopsys/nsim/Kconfig

@@ -9,4 +9,13 @@ config SYS_VENDOR
 config SYS_CONFIG_NAME
 	default "nsim"
 
+config NSIM_BOARD_CPPFLAGS
+	string "board arc-specific compiler options"
+	help
+	  For nSIM we allow to set custom arc-specific compiler options
+	  (like -mcpu=) instead of hardcoding them in its makefile as nSIM
+	  target is used for representing targets without fixed CPU version
+	  like FPGA-based boards and software simulators.
+	  This variable takes space separated compiler options list.
+
 endif

board/synopsys/nsim/config.mk

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (C) 2020 Synopsys, Inc. All rights reserved.
+
+# CONFIG_NSIM_BOARD_CPPFLAGS is a string variable which comes from defconfig
+# with double quotes. We use echo to remove them so CONFIG_NSIM_BOARD_CPPFLAGS
+# won't be treated by compiler as a single option.
+PLATFORM_CPPFLAGS += $(shell echo $(CONFIG_NSIM_BOARD_CPPFLAGS))

configs/nsim_700_defconfig

@@ -1,5 +1,6 @@
 CONFIG_ARC=y
 CONFIG_TARGET_NSIM=y
+CONFIG_NSIM_BOARD_CPPFLAGS="-mcpu=arc700 -mlock -mswape"
 CONFIG_SYS_TEXT_BASE=0x81000000
 CONFIG_DEBUG_UART_BASE=0xf0000000
 CONFIG_DEBUG_UART_CLOCK=70000000

configs/nsim_700be_defconfig

@@ -1,6 +1,7 @@
 CONFIG_ARC=y
 CONFIG_CPU_BIG_ENDIAN=y
 CONFIG_TARGET_NSIM=y
+CONFIG_NSIM_BOARD_CPPFLAGS="-mcpu=arc700 -mlock -mswape"
 CONFIG_SYS_TEXT_BASE=0x81000000
 CONFIG_DEBUG_UART_BASE=0xf0000000
 CONFIG_DEBUG_UART_CLOCK=70000000

configs/nsim_hs38_defconfig

@@ -1,6 +1,7 @@
 CONFIG_ARC=y
 CONFIG_ISA_ARCV2=y
 CONFIG_TARGET_NSIM=y
+CONFIG_NSIM_BOARD_CPPFLAGS="-mcpu=archs"
 CONFIG_SYS_TEXT_BASE=0x81000000
 CONFIG_DEBUG_UART_BASE=0xf0000000
 CONFIG_DEBUG_UART_CLOCK=70000000

configs/nsim_hs38be_defconfig

@@ -2,6 +2,7 @@ CONFIG_ARC=y
 CONFIG_ISA_ARCV2=y
 CONFIG_CPU_BIG_ENDIAN=y
 CONFIG_TARGET_NSIM=y
+CONFIG_NSIM_BOARD_CPPFLAGS="-mcpu=archs"
 CONFIG_SYS_TEXT_BASE=0x81000000
 CONFIG_DEBUG_UART_BASE=0xf0000000
 CONFIG_DEBUG_UART_CLOCK=70000000