Cross-platform MediaTek feature phone dumping had been achieved long ago with [MTreader](https://gitlab.com/suborg/mtreader). Now it's time to do the same for Unisoc (ex-Spreadtrum) phones. And not only that, but also to be able to flash them!
Unfortunately, the architecture of Unisoc chipset boot ROM doesn't allow us to get away without any loader blobs. So, some FDL binaries are also shipped in this repo.
UniFlash started out as UniDump (see [this blog post](https://chronovir.us/2021/12/18/Opus-Spreadtrum/)) but had been quickly upgraded to do both tasks.
**Note**: you need to hold a bootkey pressed when connecting the device for it to be detected correctly. This key can vary across devices. Typically it's Call, Soft Left, Soft Right, Center, 9 or #, but it can be anything else.
This is the default target for UniFlash, FDLs for it are shipped in the repo and you don't need to configure anything else (even `-t` parameter) unless your model requires signed FDLs.
For SC6531E, firmware is usually 4MB long, so you just need to run `python uniflash.py dump your-output-file.bin` to dump the firmware image and `python uniflash.py flash your-input-file.bin` to flash it.
For SC6531F or SC6531M, the target is still `sc6531efm_generic` unless your model uses signed FDLs. However, **specifying the wrong dump length and attempts to write flash from the same dump can make the device unbootable!**
SC6531C is a single-FDL variant. Here, if your model doesn't require signed FDLs, you need to specify `sc6530_generic` target and typically 8MB length, for instance, for Alcatel OT-2051D the boot key is Call key and the command to dump is: `python uniflash.py -t sc6530_generic -l 0x800000 dump ot2051d.bin`
**Note**: for SC6531C, only readback is supported as of now.
If you work with non-standard devices but don't find specifying individual FDL parameters every time convenient, you can always create your own target and refer to it via the `-t` parameter. It's pretty straightforward: you just need to collect FDL loader files for your device, rename them accordingly and place them into `fdls/` directory in the root of UniFlash project.
For two-FDL targets (more common scenario), the naming scheme is like this: `[targetname]_[load_addr_1]_fdl1.bin` and `[targetname]_[load_addr_2]_fdl2.bin`.
For single-FDL targets, the FDL file name must be `[targetname]_[load_addr]_single.bin`.
For example, if you have found signed FDL loaders for Nokia 105 2019 somewhere and want to add this phone as a target, you know that they are loaded into `0x40004000` and `0x14000000` respectively, so you can rename them, for instance, to `sc6531efm_nokia_0x40004000_fdl1.bin` and `sc6531efm_nokia_0x14000000_fdl2.bin`, place them into `fdls/` and then just use `-t sc6531efm_nokia` in your commands.
