Add (somewhat speculative) bootable CD support for PAPR/pSeries-type

systems. In principle, FreeBSD should run on at least some of these
already, and support for the remainder will hopefully show up eventually,
so add this while I'm thinking about it.

release/powerpc/mkisoimages.sh

@@ -24,6 +24,7 @@
 # into base-bits-dir as part of making the image.
 
 if [ "x$1" = "x-b" ]; then
+	# Apple boot code
 	uudecode -o /tmp/hfs-boot-block.bz2 `dirname $0`/hfs-boot.bz2.uu
 	bzip2 -d /tmp/hfs-boot-block.bz2
 	OFFSET=$(hd /tmp/hfs-boot-block | grep 'Loader START' | cut -f 1 -d ' ')
@@ -31,6 +32,19 @@ if [ "x$1" = "x-b" ]; then
 	dd if=$4/boot/loader of=/tmp/hfs-boot-block seek=$OFFSET conv=notrunc
 
 	bootable="-o bootimage=macppc;/tmp/hfs-boot-block -o no-emul-boot"
+
+	# pSeries/PAPR boot code
+	mkdir $4/ppc
+	cat > $4/ppc/bootinfo.txt << EOF
+<CHRP-BOOT>
+<DESCRIPTION>FreeBSD/powerpc</DESCRIPTION>
+<OS-NAME>FreeBSD</OS-NAME>
+<BOOT-SCRIPT>
+boot &device;:&partition;,\boot\loader &device;:0
+</BOOT-SCRIPT>
+</CHRP-BOOT>
+EOF
+
 	shift
 else
 	bootable=""
@@ -48,3 +62,5 @@ echo "/dev/iso9660/`echo $LABEL | tr '[:lower:]' '[:upper:]'` / cd9660 ro 0 0" >
 makefs -t cd9660 $bootable -o rockridge -o label=$LABEL $NAME $*
 rm $1/etc/fstab
 rm /tmp/hfs-boot-block
+rm -rf $1/ppc
+