Multiboot build system v4

In order to build the multiboot option rom, we need a Makefile and a tool
to sign the rom with.

Both are provided by this patch and mostly taken from the extboot source,
written by Anthony Liguori.

Once built, the resulting binary gets copied to pc-bios automatically.

Building also occurs automatically when on an x86 host.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

2 files changed, 127 insertions, 0 deletions

diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile
new file mode 100644
index 0000000000..c4a6f42625
--- /dev/null
+++ b/pc-bios/optionrom/Makefile
@@ -0,0 +1,48 @@
+all: build-all
+
+include ../../config-host.mak
+
+VPATH=$(SRC_PATH)/pc-bios/optionrom
+OBJCOPY=objcopy
+
+# from kernel sources - scripts/Kbuild.include
+# try-run
+# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
+# Exit code chooses option. "$$TMP" is can be used as temporary file and
+# is automatically cleaned up.
+try-run = $(shell set -e;		\
+	TMP="$(TMPOUT).$$$$.tmp";	\
+	if ($(1)) >/dev/null 2>&1;	\
+	then echo "$(2)";		\
+	else echo "$(3)";		\
+	fi;				\
+	rm -f "$$TMP")
+
+# cc-option-yn
+# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
+cc-option-yn = $(call try-run,\
+	$(CC) $(KBUILD_CFLAGS) $(1) -S -xc /dev/null -o "$$TMP",y,n)
+
+CFLAGS = -Wall -Wstrict-prototypes -Werror -fomit-frame-pointer -fno-builtin
+CFLAGS += -I$(SRC_PATH)
+ifeq ($(call cc-option-yn,-fno-stack-protector),y)
+CFLAGS += -fno-stack-protector
+endif
+
+build-all: multiboot.bin
+
+%.o: %.S
+	$(CC) $(CFLAGS) -o $@ -c $<
+
+%.img: %.o
+	$(LD) --oformat binary -Ttext 0 -o $@ $<
+
+%.bin: %.img signrom
+	./signrom $< $@
+	cp $@ $(SRC_PATH)/pc-bios/
+
+signrom: signrom.c
+	$(CC) -o $@ -g -Wall $^
+
+clean:
+	$(RM) *.o *.img *.bin signrom *~
diff --git a/pc-bios/optionrom/signrom.c b/pc-bios/optionrom/signrom.c
new file mode 100644
index 0000000000..fe8d677459
--- /dev/null
+++ b/pc-bios/optionrom/signrom.c
@@ -0,0 +1,79 @@
+/*
+ * Extended Boot Option ROM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright IBM Corporation, 2007
+ *   Authors: Anthony Liguori <aliguori@us.ibm.com>
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+int main(int argc, char **argv)
+{
+	FILE *fin, *fout;
+	char buffer[512], oldbuffer[512];
+	int i, size, lag = 0;
+	uint8_t sum = 0;
+
+	if (argc != 3) {
+		printf("Usage: %s ROM OUTPUT\n", argv[0]);
+		return 1;
+	}
+
+	fin = fopen(argv[1], "rb");
+	fout = fopen(argv[2], "wb");
+
+	if (fin == NULL || fout == NULL) {
+		fprintf(stderr, "Could not open input/output files\n");
+		return 1;
+	}
+
+	do {
+		size = fread(buffer, 512, 1, fin);
+		if (size == 1) {
+			for (i = 0; i < 512; i++)
+				sum += buffer[i];
+
+			if (lag) {
+				if (fwrite(oldbuffer, 512, 1, fout) != 1) {
+					fprintf(stderr, "Write failed\n");
+					return 1;
+				}
+			}
+			lag = 1;
+			memcpy(oldbuffer, buffer, 512);
+		}
+	} while (size == 1);
+
+	if (size != 0) {
+		fprintf(stderr, "Failed to read from input file\n");
+		return 1;
+	}
+
+	oldbuffer[511] = -sum;
+
+	if (fwrite(oldbuffer, 512, 1, fout) != 1) {
+		fprintf(stderr, "Failed to write to output file\n");
+		return 1;
+	}
+
+	fclose(fin);
+	fclose(fout);
+
+	return 0;
+}