Have you been affected by the Nexus 6P‘s infamous “Bootloop of Death”? If you are one of the unlucky few with a Nexus 6P tucked away in some drawer, you’ll be happy to know that a fix has been found that’ll enable you to fully boot up your device once more.
This has been achieved by disabling the big cluster of the device’s Snapdragon 810 SoC, which then allows the device to finally reach its lockscreen. In order to revive your Nexus 6P, you’ll need to flash modified files provided by XDA Member XCnathan32 (with the help of XDA Senior Member rchtk) in order to get your ROM and recovery working again.
Near the end of 2016, we saw a volley of reports from multiple users claiming their Nexus 6P units were inexplicably entering random bootloops, a problem seemingly separate from the early shutdowns that plagued the phone around the same time. This was different, and while reduced battery life is certainly bad, the bootloops essentially turned the smartphone into paperweight.
Users who faced this issue quickly sunk into despair as there was no remedy in sight. No amount of data wiping or re-flashing of factory images seemed to solve the problem, indicating that the issue was hardware-related, possibly a problem in the SoC. This wouldn’t be the first time for one of Google’s devices to enter devastating brick or bootloop states: the Nexus 7 saw widespread bricks upon receiving its original Lollipop OTA, and the LG-manufactured Nexus 5X suffered the same fate as many LG phones with a hardware-related bootloop as well.
The Nexus 6P’s bootloop had been confirmed by a Google representative who suggested users should contact their place of purchase for warranty or repair options. Users attempted to get a better solution out of Google, reaching out by starting a conversation in the AOSP issue tracker, and then we began hearing about a potential lawsuit being filed against Google and Huawei for both the early shutdown and bootloop issues. A class action lawsuit was ultimately filed and then amended, with claimants in more than ten states. While Google and Huawei were clearly made aware of the issue, we still haven’t seen them address the problem beyond replacing devices covered under warranty.
Bootloop of Death, Bypassed
XDA Member XCnathan32 has posted a guide and modified files that reportedly fix the Nexus 6P’s Bootloader of Death. The instructions are quite simple and they only involve flashing modified images for the boot.img and also a modified build of TWRP to flash other files after. These builds have been changed to only use the little cluster of the Snapdragon 810 SoC, effectively disabling the A57 performance cores that are seemingly preventing the device from booting. While we won’t speculate as to why this is, it does mean that you’ll encounter noticeable lag, though the A53 little cores are also more power efficient — it’s quite the tradeoff, but it’s certainly better than nothing.
Multiple users have reported that the modified images provided in the opening post are working and allow the device to boot, and we tried it ourselves on a bootlooping Nexus 6P unit to confirm as well. First, you need an unlocked bootloader. If your bootloader hasn’t been unlocked, you should still be able to do so if you enabled OEM unlocking before. You will need to use fastboot in order to flash the following images, with the command listed alongside it. The files supplied by XCnathan32 are:
This is the boot.img from the latest 7.1.2 firmware, put together by XCnathan32 and modified to use only the four little cores. This should allow your device to fully load up your ROM. Make sure that the file is either in your fastboot directory, or that you navigate to the folder where this file is downloaded. If you’ve set up adb & fastboot system-wide, open a command prompt in the folder with this file by shift-clicking within the folder, and selecting “open Command Prompt/Power Shell Window here”.
This is TWRP 3.1.1, again modified to use only four cores; it’ll enable TWRP on your device, allowing you to flash other files such as custom ROMs and kernels, which should help you cope with the penalties of using only four less-powerful cores.
This is XDA Recognized Developer flar2‘s excellent Elemental X kernel V4.1.1, also modified to use 4 cores. This should net you better performance than that of the stock kernel, and you’ll be able to overclock the little cluster in order to get more juice out of what you are limited to.
XCnathan32 does note that root works by flashing SuperSU in TWRP. He also offered a few suggestions to get more performance out of your device, such as disabling animations, overclocking the little cores, and changing the CPU governor to an aggressive one. While he tested the modified boot.img on a stock ROM, other ROMs such as PureNexus should be able to work as well — you just need to make sure you are running a kernel that’s modified to use the four little cores.
This is an impressive development and Nexus 6P owners are now able to revive their excellent device, even if there are compromises to this solution. Given there are many users who were unable to get their units replaced under warranty, they can now put the phone to good use instead of having it sit dead in a corner or drawer.