Boot option
Boot introduce
First, let's make the concept clear, there are many boot stages when we boot up a Linux OS;
Then we need to know about how the image should packaged, where the image locate;
At last, we will explain how to write to different media and boot from there.
Here is Rockchip pre-released binaries which may be mentioned later:
https://github.com/rockchip-linux/rkbin
Boot flow
Here is a table show the detail what we may use in Rockchip platform, for 2 boot stage:
- use U-Boot SPL;
- use Rockchp idbLoader which is combinded by Rockchip ddr init bin and miniloader bin;
+--------+----------------+----------+-------------+---------+ | Boot | Terminology #1 | Actual | Rockchip | | | stage | | program | Image | | | number | | name | Name | | +--------+----------------+----------+-------------+---------+ | 1 | Primary | ROM code | BootRom | | | | Program | | | | | | Loader | | | | | | | | | | | 2 | Secondary | U-Boot |idbloader.img| 0x40 |including u-boot if not use miniloader | | Program | SPL |idbspl.img | | | | Loader (SPL) | | | | | | | | | | | 3 | - | U-Boot | u-boot.itb | 0x4000 | including u-boot and atf | | | | u-boot.bin | 0x4000 | | | | | uboot.img | 0x4000 | only used with miniloader | | | | | | | | | ATF | trust.img | 0x6000 | only used with miniloader for armv8 | | | | | | | 4 | - | kernel | boot.img | 0x8000 | | | | | | | | 5 | - | rootfs | rootfs.img | 0x40000 | +--------+----------------+----------+-------------+---------+
Then when we talking about boot from eMMC/SD/U-Disk/net, they are in different concept:
- Stage 1 is always in boot rom, it loads stage 2 and may load stage 3(when SPL_BACK_TO_BROM option enabled).
- Boot from SPI flash means firmware for stage 2 and 3(SPL and U-Boot only) in SPI flash and stage 4/5 in other place;
- Boot from eMMC means all the firmware(including stage 2, 3, 4, 5) in eMMC;
- Boot from SD card means all the firmware(including stage 2, 3, 4, 5) in SD card;
- Boot from U-Disk means firmware for stage 4 and 5(not including SPL and U-Boot) in Disk, optionally only including stage 5;
- Boot from net/tftp means firmeware for stage 4 and 5(not including SPL and U-Boot) on the network;
(Thanks to Fu Wei from RedHat who is the author of these two flow diagram.)
Note 1. The concept of BL1/BL2/BL3 are from ARMv8 only.
Package option
After we know about the boot stages,
Here are the file list before package for stage 2~4:
- From source code:
- From U-Boot: u-boot-spl.bin, u-boot.bin(may use u-boot-nodtb.bin and u-boot.dtb instead),
- From kernel: kernel Image/zImage file, kernel dtb,
- From ATF: bl31.bin;
- From Rockchip binary:
- ddr, usbplug, miniloader, bl31, (all with chip 'rkxx_' prefix and with version '_x.xx.bin' postfix);
Here are the types to package image from those files:
idbspl.img
U-Boot SPL, with SPL_BACK_TO_BROM option disabled.
mkimage -n rkxxxx -T rksd -d spl/u-boot-spl.bin idbspl.img
Flash the idbspl.img to offset 0x40 which only including stage 2, and need flash stage 3 image to 0x200(which is defineded by CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR), the stage 3 image may be u-boot.bin directly(when there no ATF requirement), or FIT image bl3.itb(for ATF load from SPL, including bl31.bin, u-boot-nodtb.bin and u-boot.dtb).
idbloader.img
U-Boot SPL, with SPL_BACK_TO_BROM option enabled:
tools/mkimage -n rkxxxx -T rksd -d spl/u-boot-spl.bin idbloader.img cat u-boot.bin >> idbloader.img
Flash the idbloader.img to offset 0x40 which including boot stage 2 and 3.
Package the image from Rockchip binary:
dd if=rkxx_ddr_vx.xx.bin of=ddr.bin bs=4 skip=1 tools/mkimage -n rkxxxx -T rksd -d ddr.bin idbloader.img rm ddr.bin cat rkxx_miniloader_vx.xx.bin >> idbloader.img
Flash the idbloader.img to offset 0x40 which including stage 2, and you will need a uboot.img for boot stage 3.
bl3.itb
When using SPL to load the ATF, package the bl31.bin, u-boot-nodtb.bin and uboot.dtb into one FIT image.
tools/mkimage -f fit4spl.its -E bl3.itb
Flash the bl3.itb to offset 0x200, while need idbspl.img flasht to offset 0x40.
uboot.img
When using idbLoader from Rockchip miniloader, need package u-boot.bin into miniloader loadable format by Rockchip tool loaderimage.
tools/loaderimage --pack --uboot u-boot.bin uboot.img
Flash the uboot.img to offset 0x4000 which is stage 3;
trust.img
When using idbLoader from Rockchip miniloader, need package bl31.bin into miniloader loadable format by Rockchip tool trustmerge.
tools/trustmerge tools/rk_tools/RKTRUST_RKXXXXTRUST.ini
Flash the trust.img to offset 0x6000 which is for using Rockchip miniloader
rkxx_loader_vx.xx.xxx.bin
This is provide by Rockchip in binary mode, which is used for firmware upgrade to eMMC with rkdeveloptool, can not be wirte to media device directly.
This is a package from ddr.bin, usbplug.bin, miniloader.bin, Rockchip tool DB command will make usbplug.bin running in target which perform as a Rockusb device.
boot.img
This image is package the kernel Image and dtb file into a know filesystem(FAT or EXT2) image for distro boot.
See Install kernel for detail about generate boot.img from kernel zImage/Image, dtb.
Flash the boot.img to offset 0x8000 which is stage 4.
rootfs.img
Flash the rootfs.img to offset 0x40000 which is stage 5.
Flash and boot from Media device
Here we introduce how to write image to different Medeia device.
Get image Ready:
- For armv7 with SPL with SPL_BACK_TO_BROM option enabled:
- idbLoader.img
- boot.img or boot folder with zImage, dtb and exitlinulx inside
- rootfs.img
- For armv7 with SPL with SPL_BACK_TO_BROM option disabled:
- idbspl.img
- u-boot.bin
- boot.img or boot folder with zImage, dtb and exitlinulx inside
- rootfs.img
- For armv7 with miniloader
- idbLoader.img
- uboot.img
- boot.img or boot folder with zImage, dtb and exitlinulx inside
- rootfs.img
- For armv8 with SPL:
- idbspl.img
- bl3.itb
- boot.img or boot folder with Image, dtb and exitlinulx inside
- rootfs.img
- For armv8 with miniloader
- idbLoader.img
- uboot.img
- trust.img
- boot.img or boot folder with Image, dtb and exitlinulx inside
- rootfs.img
Boot from eMMC
The eMMC is on the hardware board, so we need:
- Get the board into maskrom mode;
- Connect the target to PC with USB cable;
- Flash the image to eMMC with rkdeveloptool
Example commands for flash image to target.
Flash the gpt partition to target:
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool gpt parameter_gpt.txt
- For armv7 with SPL with SPL_BACK_TO_BROM option enabled(rk3036, rk3188, rk3288):
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool wl 0x40 idbloader.img rkdeveloptool wl 0x8000 boot.img rkdeveloptool wl 0x40000 rootfs.img rkdeveloptool rd
- For armv7 with SPL with SPL_BACK_TO_BROM option disabled(rk3288):
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool wl 0x40 idbspl.img rkdeveloptool wl 0x200 u-boot.bin rkdeveloptool wl 0x8000 boot.img rkdeveloptool wl 0x40000 rootfs.img rkdeveloptool rd
- For armv7 with miniloader(rk3036, rk3188, rk3288)
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool wl 0x40 idbloader.img rkdeveloptool wl 0x4000 uboot.img rkdeveloptool wl 0x8000 boot.img rkdeveloptool wl 0x40000 rootfs.img rkdeveloptool rd
- For armv8 with SPL(rk3399):
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool wl 0x40 idbspl.img rkdeveloptool wl 0x200 bl3.itb rkdeveloptool wl 0x8000 boot.img rkdeveloptool wl 0x40000 rootfs.img rkdeveloptool rd
- For armv8 with miniloader(rk3399, rk3328)
rkdeveloptool db rkxx_loader_vx.xx.bin rkdeveloptool wl 0x40 idbloader.img rkdeveloptool wl 0x4000 uboot.img rkdeveloptool wl 0x6000 trust.img rkdeveloptool wl 0x8000 boot.img rkdeveloptool wl 0x40000 rootfs.img rkdeveloptool rd
Boot from SD/TF Card
We can write SD/TF card with Linux PC dd command very easily.
Insert SD card to PC and we assume the /dev/sdb is the SD card device.
- For armv7 with SPL with SPL_BACK_TO_BROM option enabled(rk3036, rk3188, rk3288):
dd if=idbloader.img of=sdb seek=64 dd if=boot.img of=sdb seek=32768 dd if=rootfs.img of=sdb seek=262144
- For armv7 with SPL with SPL_BACK_TO_BROM option disabled(rk3288):
dd if=idbspl.img of=sdb seek=64 dd if=u-boot.bin of=sdb seek=512 dd if=boot.img of=sdb seek=32768 dd if=rootfs.img of=sdb seek=262144
- For armv7 with miniloader(rk3036, rk3188, rk3288)
dd if=idbloader.img of=sdb seek=64 dd if=uboot.img of=sdb seek=16384 dd if=boot.img of=sdb seek=32768 dd if=rootfs.img of=sdb seek=262144
- For armv8 with SPL(rk3399):
dd if=idbspl.img of=sdb seek=64 dd if=bl3.itb of=sdb seek=512 dd if=boot.img of=sdb seek=32768 dd if=rootfs.img of=sdb seek=262144
- For armv8 with miniloader(rk3399, rk3328)
dd if=idbloader.img of=sdb seek=64 dd if=uboot.img of=sdb seek=16384 dd if=trust.img of=sdb seek=24576 dd if=boot.img of=sdb seek=32768 dd if=rootfs.img of=sdb seek=262144
In order to make sure everything has write to SD card before unpluged, recommand to run below command:
sync
Note, when using boot from SD card, need to update the kernel cmdline(which is in extlinux.conf) for the correct root value.
append earlyprintk console=ttyS2,115200n8 rw root=/dev/mmcblk1p7 rootwait rootfstype=ext4 init=/sbin/init
Write GPT partition table to SD card in U-Boot, and then U-Boot can find the boot partition and run into kernel.
gpt write mmc 0 $partitions
Boot from U-Disk
Same as boot-from-sdcard, but please note that U-Disk only support stage 4 and 5, see Boot Stage for detail.
If U-Disk used for stage 4 and 5, format the U-Disk in gpt format and at least 2 partitions, write boot.img and rootfs.img in those partitions;
if U-Dist is only used for stage 5, we can dd the rootfs.img to U-Disk device directly.
Note, need to update the kernel cmdline(which is in extlinux.conf) for the correct root value.
append earlyprintk console=ttyS2,115200n8 rw root=/dev/sda1 rootwait rootfstype=ext4 init=/sbin/init
Boot from Network
