linux: add support of Synopsys ARCHS38-based boards

This patch introduces support of new boards with ARC HS38 cores.

ARC HS38 is a new generation of ARC cores which utilize ARCv2 ISA.
As with ARC770 we're addind support for 2 boards for now:

 [1] Synopsys SDP board (AXS103)
     This is the same base-board as in AXS101 but with
     FPGA-based CPU-tile where ARCHs38 core is implemented.

 [2] nSIM
     Again this is the same simulation engine but configured for
     new instruction set and features of new CPU.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Felix Fietkau <nbd@openwrt.org>
Cc: Jo-Philipp Wich <jow@openwrt.org>
Cc: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 48740

target/linux/archs38/base-files/lib/arc.sh

@@ -0,0 +1,50 @@
+#!/bin/sh
+#
+# Copyright (C) 2016 OpenWrt.org
+#
+
+# defaults
+ARC_BOARD_NAME="generic"
+ARC_BOARD_MODEL="Generic ARC board"
+
+arc_board_detect() {
+	local board
+	local model
+	local compatible
+
+	[ -e "/tmp/sysinfo/" ] || mkdir -p "/tmp/sysinfo/"
+
+	model="$( cat /proc/device-tree/model )"
+	compatible="$( cat /proc/device-tree/compatible )"
+
+	case "$compatible" in
+	"snps,axs103""snps,arc-sdp")
+		board="arc-sdp";
+		;;
+	"snps,nsim_hs")
+		board="arc-nsim";
+		;;
+	esac
+
+	if [ "$board" != "" ]; then
+		ARC_BOARD_NAME="$board"
+	fi
+
+	if [ "$model" != "" ]; then
+		ARC_BOARD_MODEL="$model"
+	fi
+
+	echo "$ARC_BOARD_NAME" > /tmp/sysinfo/board_name
+	echo "$ARC_BOARD_MODEL" > /tmp/sysinfo/model
+	echo "Detected $ARC_BOARD_NAME // $ARC_BOARD_MODEL"
+}
+
+arc_board_name() {
+	local name
+
+	[ -f /tmp/sysinfo/board_name ] && name="$(cat /tmp/sysinfo/board_name)"
+	[ -z "$name" ] && name="unknown"
+
+	echo "$name"
+}
+