MediaTek MT6735

MT6735 is a low-end Mediatek SoC released in 2014 and used in many cheap devices. Variants include the MT6735P and MT6735M with CPU clocks lowered to 1.0 GHz. Mediatek also released some other variants in 2016 including MT6737 with a 1.25 GHz CPU clock, and MT6737T with a 1.5 GHz CPU clock.

Codenamed Denali-3, MT6753 is a SoC that shares the same architecture of MT6735 while having double the ARM Cortex-A53 CPUs in a dual cluster arrangement, as well as an ARM Mali-T720 MP3 GPU.

U-Boot
The U-Boot port for mt6735 is being actively developed and is available at https://github.com/alifilhan0/u-boot The purpose of this port is to replace the stock mediatek lk, which, due to its quirks, does not allow the development of mainline linux to continue. Also, as a bonus, you can get linux boot from a microsd card or even a usb flash drive (via usb otg). But at the moment, development has just begun and U-Boot is not working on this SoC yet, but you can fix it! If you are interested in the mainline on mt6735 join #u-boot-mt6735:matrix.org or here https://github.com/arzam16/linux-mt6577/issues/1

MMIO Block Overview
Base addresses of a few memory-mapped I/O blocks on MT6735 are shown here. MT6735M might have some slight differences:

eFuse Controller
This SoC has an efuse controller with several efuses used for storing calibration and performance data used for thermal management and frequency scaling, as well as a few efuses for security features such as SLA (Serial Link Authorization), SBC (Secure Boot) and DAA (Download Agent Authentication). Some Known efuses are listed here: