U-Boot for the HTC One X (endeavoru)
DISCLAMER!
Moving your HTC ONe X to use U-Boot assumes replacement of the
vendor hboot. Vendor android firmwares will no longer be able to run on the
device. This replacement IS reversible.
Quick Start
Build U-Boot
Process U-Boot
Flashing U-Boot into the eMMC
Boot
Self Upgrading
Build U-Boot
$ export CROSS_COMPILE=arm-linux-gnueabi-
$ make endeavoru_defconfig
$ make
After the build succeeds, you will obtain the final u-boot-dtb-tegra.bin
image, ready for further processing.
Process U-Boot
DISCLAMER!
All questions related to the re-crypt work should be asked
in re-crypt repo issues. NOT HERE!
re-crypt is a tool that processes the u-boot-dtb-tegra.bin
binary into form
usable by device. This process is required only on the first installation or
to recover the device in case of a failed update.
Permanent installation can be performed either by using the nv3p protocol or by pre-loading just built U-Boot into RAM.
Processing for the NV3P protocol
$ git clone https://gitlab.com/grate-driver/re-crypt.git
$ cd re-crypt # place your u-boot-dtb-tegra.bin here
$ ./re-crypt.py --dev endeavoru
The script will produce a repart-block.bin
ready to flash.
Processing for pre-loaded U-Boot
The procedure is the same, but the --split
argument is used with the
re-crypt.py
. The script will produce bct.img
and ebt.img
ready
to flash.
Flashing U-Boot into the eMMC
DISCLAMER!
All questions related to NvFlash should be asked in the proper
place. NOT HERE! Flashing U-Boot will erase all eMMC, so make a backup before!
Permanent installation can be performed either by using the nv3p protocol or by pre-loading just built U-Boot into RAM.
Flashing with the NV3P protocol
Nv3p is a custom Nvidia protocol used to recover bricked devices. Devices can
enter it either by using wheelie
with the correct blob.bin
file or by
pre-loading vendor bootloader with the Fusée Gelée.
With nv3p, repart-block.bin
is used. It contains BCT and a bootloader in
encrypted state in form, which can just be written RAW at the start of eMMC.
$ wheelie --blob blob.bin
$ nvflash --resume --rawdevicewrite 0 1024 repart-block.bin
When flashing is done, reboot the device.
Flashing with a pre-loaded U-Boot
U-Boot pre-loaded into RAM acts the same as when it was booted “cold”. Currently U-Boot supports bootmenu entry fastboot, which allows to write a processed copy of U-Boot permanently into eMMC.
While pre-loading U-Boot, hold the volume down
button which will trigger
the bootmenu. There, select fastboot
using the volume and power buttons.
After, on host PC, do:
$ fastboot flash 0.1 bct.img
$ fastboot flash 0.2 ebt.img
$ fastboot reboot
Device will reboot.
Boot
To boot Linux, U-Boot will look for an extlinux.conf
on eMMC. Additionally,
if the Volume Down button is pressed while booting, the device will enter
bootmenu. Bootmenu contains entries to mount eMMC as mass storage, fastboot,
reboot, reboot RCM, poweroff, enter U-Boot console and update bootloader (check
the next chapter).
Flashing repart-block.bin
eliminates vendor restrictions 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 eMMC (using
ability of u-boot to mount it). 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.