| .. SPDX-License-Identifier: GPL-2.0+ |
| |
| U-Boot for the ASUS Transformer device family |
| ============================================= |
| |
| ``DISCLAMER!`` Moving your ASUS Transformer to use U-Boot |
| assumes replacement of the vendor ASUS bootloader. Vendor |
| android firmwares will no longer be able to run on the device. |
| This replacement IS reversible. |
| |
| Quick Start |
| ----------- |
| |
| - Build U-Boot |
| - Pack U-Boot into repart-block |
| - Flash repart-block into the eMMC |
| - Flash repart-block into TF600T SPI flash |
| - Boot |
| - Self Upgrading |
| |
| Build U-Boot |
| ------------ |
| |
| Device support is implemented by applying config fragment |
| to a generic board defconfig. Valid fragments are ``tf201.config``, |
| ``tf300t.config``, ``tf300tg.config``, ``tf300tl.config``, |
| ``tf700t.config``, ``tf600t.config`` and ``p1801-t.config``. |
| |
| .. code-block:: bash |
| |
| $ export CROSS_COMPILE=arm-linux-gnueabi- |
| $ make transformer_t30_defconfig tf201.config # For TF201 |
| $ make |
| |
| After the build succeeds, you will obtain the final ``u-boot-dtb-tegra.bin`` |
| image, ready for flashing (but check the next section for additional |
| adjustments). |
| |
| Pack U-Boot into repar-block |
| ---------------------------- |
| |
| ``DISCLAMER!`` All questions related to re-crypt work should be asked |
| in re-crypt repo issues. NOT HERE! |
| |
| re-crypt is a small script which packs ``u-boot-dtb-tegra.bin`` in |
| form usable by device. This process is required only on the first |
| installation or to recover the device in case of a failed update. |
| You need to know your tablet's individual SBK to continue. |
| |
| .. code-block:: bash |
| |
| $ git clone https://github.com/clamor-s/re-crypt.git |
| $ cd re-crypt # place your u-boot-dtb-regra.bin here |
| $ ./re-crypt.sh -d tf201 -k deadbeefdeadc0dedeadd00dfee1dead |
| |
| Script will produce you a `repart-block.bin` ready to flash. |
| |
| Flash repart-block into the eMMC |
| -------------------------------- |
| |
| ``DISCLAMER!`` All questions related to NvFlash should be asked |
| in the proper place. NOT HERE! Flashing repart-block will erase |
| all your eMMC, so make a backup before! |
| |
| ``repart-block.bin`` contains BCT and bootloader in encrypted state |
| in form which can just be written RAW at the start of eMMC. |
| |
| .. code-block:: bash |
| |
| $ wheelie --blob blob.bin |
| $ nvflash --resume --rawdevicewrite 0 1024 repart-block.bin |
| |
| Flash repart-block into TF600T SPI flash |
| ---------------------------------------- |
| |
| Unlike other transformers TF600T uses separate 4 MB SPI flash which |
| contains all data required for boot. It is flashed from within u-boot |
| itself preloaded into RAM using fusee gelee. After creating your |
| ``repart-block.bin`` you have to place it on a 1st partition of microSD |
| card formated in fat. Then insert this microSD card into your tablet |
| and boot it using fusee gelee and u-boot which was included into |
| repart-block.bin, while booting you must hold volume down button. |
| Process should take less then a minute, if everything goes correct, |
| on microSD will appear ``spi-flash-backup.bin`` file, which is dump of |
| your spi flash content and can be used to restore UEFI, do not loose it, |
| tablet will power itself off. |
| |
| Self-updating of u-boot is performed by placing ``u-boot-dtb-tegra.bin`` |
| on 1st partition of microSD, inserting it into tablet and booting with |
| pressed volume down button. |
| |
| Boot |
| ---- |
| |
| After flashing ``repart-block.bin`` the device should reboot and turn |
| itself off. This is normal behavior if no boot configuration is |
| found. |
| |
| To boot Linux, U-Boot will look for an ``extlinux.conf`` on MicroSD |
| and then on eMMC. Additionally if Volume Down button is pressed |
| while booting device will enter bootmenu. Bootmenu contains entries |
| to mount MicroSD and eMMC as mass storage, fastboot, reboot, reboot |
| RCM, poweroff, enter U-Boot console and update bootloader (check next |
| chapter). |
| |
| Flashing ``repart-block.bin`` eliminates vendor restriction on eMMC |
| and allows the user to use/partition it in any way the user desires. |
| |
| Self Upgrading |
| -------------- |
| |
| Place your ``u-boot-dtb-tegra.bin`` on the first partition of the |
| MicroSD card and insert it into the tablet. Enter bootmenu, choose |
| update bootloader option with Power button and U-Boot should update |
| itself. Once the process is completed, U-Boot will ask to press any |
| button to reboot. |