| U-boot for Odroid X2/U3 |
| ======================== |
| |
| 1. Summary |
| ========== |
| This is a quick instruction for setup Odroid boards based on Exynos4412. |
| Board config: odroid_config |
| |
| 2. Supported devices |
| ==================== |
| This U-BOOT config can be used on two boards: |
| - Odroid U3 |
| - Odroid X2 |
| with CPU Exynos 4412 rev 2.0 and 2GB of RAM |
| |
| 3. Boot sequence |
| ================ |
| iROM->BL1->(BL2 + TrustZone)->U-BOOT |
| |
| This version of U-BOOT doesn't implement SPL but it is required(BL2) |
| and can be found in "boot.tar.gz" from here: |
| http://dev.odroid.com/projects/4412boot/wiki/FrontPage?action=download&value=boot.tar.gz |
| or here: |
| http://odroid.in/guides/ubuntu-lfs/boot.tar.gz |
| |
| 4. Boot media layout |
| ==================== |
| The table below shows SD/eMMC cards layout for U-boot. |
| The block offset is starting from 0 and the block size is 512B. |
| ------------------------------------- |
| | Binary | Block offset| part type | |
| | name | SD | eMMC |(eMMC only)| |
| ------------------------------------- |
| | Bl1 | 1 | 0 | 1 (boot) | |
| | Bl2 | 31 | 30 | 1 (boot) | |
| | U-boot | 63 | 62 | 1 (boot) | |
| | Tzsw | 2111 | 2110 | 1 (boot) | |
| | Uboot Env | 2500 | 2500 | 0 (user) | |
| ------------------------------------- |
| |
| 5. Prepare the SD boot card - with SD card reader |
| ================================================= |
| To prepare bootable media you need boot binaries provided by hardkernel. |
| File "boot.tar.gz" (link in point 3.) contains: |
| - E4412_S.bl1.HardKernel.bin |
| - E4412_S.tzsw.signed.bin |
| - bl2.signed.bin |
| - sd_fusing.sh |
| - u-boot.bin |
| |
| This is all you need to boot this board. But if you want to use your custom |
| u-boot then you need to change u-boot.bin with your own u-boot binary* |
| and run the script "sd_fusing.sh" - this script is valid only for SD card. |
| |
| *note: |
| The proper binary file of current U-boot is u-boot-dtb.bin. |
| |
| quick steps for Linux: |
| - extract boot.tar.gz |
| - put any SD card into the SD reader |
| - check the device with "dmesg" |
| - run ./sd_fusing.sh /dev/sdX - where X is SD card device (but not a partition) |
| Check if Hardkernel U-boot is booting, and next do the same with your U-boot. |
| |
| 6. Prepare the eMMC boot card |
| with a eMMC card reader (boot from eMMC card slot) |
| ===================================================== |
| To boot the device from the eMMC slot you should use a special card reader |
| which supports eMMC partiion switch. All of the boot binaries are stored |
| on the eMMC boot partition which is normally hidden. |
| |
| The "sd_fusing.sh" script can be used after updating offsets of binaries |
| according to the table from point 4. Be sure that you are working on the right |
| eMMC partition - its size is usually very small, about 1-4 MiB. |
| |
| 7. Prepare the eMMC boot card |
| with a SD card reader (boot from SD card slot) |
| ================================================= |
| If you have an eMMC->microSD adapter you can prepare the card as in point 5. |
| But then the device can boot only from the SD card slot. |
| |
| 8. Prepare the boot media using Hardkernel U-boot |
| ================================================= |
| You can update the U-boot to the custom one if you have an working bootloader |
| delivered with the board on a eMMC/SD card. Then follow the steps: |
| - install the android fastboot tool |
| - connect a micro usb cable to the board |
| - on the U-boot prompt, run command: fastboot (as a root) |
| - on the host, run command: "fastboot flash bootloader u-boot-dtb.bin" |
| - the custom U-boot should start after the board resets. |
| |
| 9. Partition layout |
| ==================== |
| Default U-boot environment is setup for fixed partiion layout. |
| |
| Partition table: MSDOS. Disk layout and files as listed in the table below. |
| ----- ------ ------ ------ -------- --------------------------------- |
| | Num | Name | FS | Size | Offset | Reguired files | |
| | | | Type | MiB | MiB | | |
| ----- ------ ------ ------ -------- --------------------------------- |
| | 1 | BOOT | fat | 100 | 2 | kernel, fdt** | |
| | 2 | ROOT | ext4 | - | | any Linux system | |
| ----- ------ ------ ------ -------- --------------------------------- |
| |
| **note: |
| Supported fdt files are: |
| - exynos4412-odroidx2.dtb |
| - exynos4412-odroidu3.dtb |
| |
| Supported kernel files are: |
| - Image.itb |
| - zImage |
| - uImage |
| |
| The default environmental variable "dfu_alt_info" is set* for above layout. |
| Each partition size is just an example, dfu_alt_info tries init two partitions. |
| The size of each is not important. |
| |
| *note: |
| $dfu_alt_info is set on a boot time and it is concatenated using two variables: |
| - $dfu_alt_boot(set dynamically) |
| - $dfu_alt_system(from current env). |
| |
| To add any changes to dfu_alt_info - please modify $dfu_alt_system only. |
| Changes are visible after board reset. |
| |
| 10. The environment and booting the kernel |
| ========================================== |
| There are three macros defined in config for various boot options: |
| Two for both, kernel with device tree support and also without it: |
| - boot_uimg - load uImage |
| - boot_zimg - load zImage |
| If proper fdt file exists then it will be automatically loaded, |
| so for old kernel types, please remove fdt file from boot partition. |
| |
| The third boot option for multi image support (more info: doc/uImage.FIT/) |
| - boot_fit - for binary file: "Image.itb" |
| |
| Default boot command: "autoboot" |
| And the boot sequence is: |
| - boot_fit - if "Image.itb" exists |
| - boot_zimg - if "zImage" exists |
| - boot_uimg - if "uImage" exists |