util/riscvtools: Add script that turns coreboot.rom into an ELF

This is required because SPIKE doesn't support loading flat files yet.

Change-Id: If745d78712ca8108b5dcc21591201bc2d3f70b86
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/14964
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

util/riscvtools/make-spike-elf.sh

@@ -0,0 +1,27 @@
+#!/bin/sh
+#
+# This script is based on:
+# https://docs.google.com/document/d/1Pvf9Yxorcd3sbgs8WcomcTl3J4bmX6e1UE0ROCefR88
+
+set -e
+
+usage() {
+	echo "This script converts a flat file into an ELF, that can be passed"
+	echo "to SPIKE, the RISC-V reference emulator."
+	echo ""
+	echo "Usage: $0 coreboot.rom coreboot.elf"
+}
+
+if [ $# -ne 2 ]; then
+	usage
+	exit 1
+fi
+
+FLAT_FILE="$1"
+OBJECT_FILE=$(mktemp /tmp/coreboot-spike.XXXXXX.o)
+ELF_FILE="$2"
+TOOL_PATH="$(dirname "$0")"
+
+objcopy -I binary -O elf32-i386 --binary-architecture i386 "$FLAT_FILE" "$OBJECT_FILE"
+ld -m elf_i386 "$OBJECT_FILE" -T "$TOOL_PATH/spike-elf.ld" -o "$ELF_FILE"
+rm "$OBJECT_FILE"

util/riscvtools/spike-elf.ld

@@ -0,0 +1,11 @@
+/* See make-spike-elf.sh */
+
+ENTRY(_start);
+SECTIONS
+{
+	. = 0x80000000;
+	_start = .;
+	.data : {
+		*(.data)
+	}
+}