samsung: common: add example boot scripts

This commit adds example scripts of boot.scr:
- bootzimg.cmd - check if dtb exists and boot zImage
- autoboot.cmd - check which image exists: Image.itb, zImage or uImage
                 and optionally load fdt file for u/zImage

The blank spaces are added to improve readability and can be removed
before use mkimage.

Required U-Boot environment variables: $boardname, $fdtfile, $console,
$mmcbootdev, $mmcbootpart, $mmcrootdev, $mmcrootpart, $rootfstype.

Making boot.scr from file.cmd:
 mkimage -C none -A arm -T script -d file.cmd boot.scr

The Odroid XU3 default environment is ready for those boot scripts and
the right script can be loaded by DFU.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>

board/samsung/common/bootscripts/autoboot.cmd

@@ -0,0 +1,92 @@
+# This is an example file to generate boot.scr - a boot script for U-Boot
+# Generate boot.scr:
+# ./tools/mkimage -c none -A arm -T script -d autoboot.cmd boot.scr
+#
+# It requires a list of environment variables to be defined before load:
+# platform dependent: boardname, fdtfile, console
+# system dependent: mmcbootdev, mmcbootpart, mmcrootdev, mmcrootpart, rootfstype
+#
+setenv fdtaddr     "40800000"
+setenv initrdname  "uInitrd"
+setenv initrdaddr  "42000000"
+setenv loaddtb     "load mmc ${mmcbootdev}:${mmcbootpart} ${fdtaddr} ${fdtfile}"
+setenv loadinitrd  "load mmc ${mmcbootdev}:${mmcbootpart} ${initrdaddr} ${initrdname}"
+setenv loadkernel  "load mmc ${mmcbootdev}:${mmcbootpart} '${kerneladdr}' '${kernelname}'"
+setenv kernel_args "setenv bootargs ${console} root=/dev/mmcblk${mmcrootdev}p${mmcrootpart} rootfstype=${rootfstype} rootwait ${opts}"
+
+#### Routine: check_dtb - check that target.dtb exists on boot partition
+setenv check_dtb "
+if test -e mmc '${mmcbootdev}':'${mmcbootpart}' '${fdtfile}'; then
+	run loaddtb;
+	setenv fdt_addr ${fdtaddr};
+else
+	echo Warning! Booting without DTB: '${fdtfile}'!;
+	setenv fdt_addr;
+fi;"
+
+#### Routine: check_ramdisk - check that uInitrd exists on boot partition
+setenv check_ramdisk "
+if test -e mmc '${mmcbootdev}':'${mmcbootpart}' '${initrdname}'; then
+	echo "Found ramdisk image.";
+	run loadinitrd;
+	setenv initrd_addr ${initrdaddr};
+else
+	echo Warning! Booting without RAMDISK: '${initrdname}'!;
+	setenv initrd_addr -;
+fi;"
+
+#### Routine: boot_fit - check that env $boardname is set and boot proper config of ITB image
+setenv setboot_fit "
+if test -e '${boardname}'; then
+	setenv fdt_addr ;
+	setenv initrd_addr ;
+	setenv kerneladdr  0x42000000;
+	setenv kernelname  Image.itb;
+	setenv itbcfg      \#'${boardname}';
+	setenv imgbootcmd  bootm;
+else
+	echo Warning! Variable: \$boardname is undefined!;
+fi"
+
+#### Routine: setboot_uimg - prepare env to boot uImage
+setenv setboot_uimg "
+	setenv kerneladdr 0x40007FC0;
+	setenv kernelname uImage;
+	setenv itbcfg     ;
+	setenv imgbootcmd bootm;
+	run check_dtb;
+	run check_ramdisk;"
+
+#### Routine: setboot_zimg - prepare env to boot zImage
+setenv setboot_zimg "
+	setenv kerneladdr 0x40007FC0;
+	setenv kernelname zImage;
+	setenv itbcfg     ;
+	setenv imgbootcmd bootz;
+	run check_dtb;
+	run check_ramdisk;"
+
+#### Routine: boot_img - boot the kernel after env setup
+setenv boot_img "
+	run loadkernel;
+	run kernel_args;
+	'${imgbootcmd}' '${kerneladdr}${itbcfg}' '${initrd_addr}' '${fdt_addr}';"
+
+#### Routine: autoboot - choose proper boot path
+setenv autoboot "
+if test -e mmc 0:${mmcbootpart} Image.itb; then
+	echo Found kernel image: Image.itb;
+	run setboot_fit;
+	run boot_img;
+elif test -e mmc 0:${mmcbootpart} zImage; then
+	echo Found kernel image: zImage;
+	run setboot_zimg;
+	run boot_img;
+elif test -e mmc 0:${mmcbootpart} uImage; then
+	echo Found kernel image: uImage;
+	run setboot_uimg;
+	run boot_img;
+fi;"
+
+#### Execute the defined autoboot macro
+run autoboot

board/samsung/common/bootscripts/bootzimg.cmd

@@ -0,0 +1,10 @@
+setenv kernelname zImage;
+setenv boot_kernel "setenv bootargs \"${console} root=/dev/mmcblk${mmcrootdev}p${mmcrootpart} rootfstype=${rootfstype} rootwait ${opts}\";
+load mmc ${mmcbootdev}:${mmcbootpart} 0x40007FC0 '${kernelname}';
+if load mmc ${mmcbootdev}:${mmcbootpart} 40800000 ${fdtfile}; then
+	bootz 0x40007FC0 - 40800000;
+else
+	echo Warning! Booting without DTB: '${fdtfile}'!;
+	bootz 0x40007FC0 -;
+fi;"
+run boot_kernel;