Question on upgrading bootloader

[guiso98]

Hello

I have the L22 variant, with TWRP installed and CM12.
Bootloader is unlocked.

I want to upgrade to CM13. It won't flash because I need to upgrade to a marshmallow (MM) bootloader first.

I extracted boot.img from an official MM rom using the update extractor.

Questions:

1. If I flash it, do I need to go again thru the procedure of bootlader unlook? (getting the code from the huawei site)
If so, I'd assume the code I used first will work, for some reason CM12 is now reporting different serial number. Though I saved the original values.

2. If I flash it, will CM12 boot? Or I will need to also flash system.img, which I also extracted.

3. If I flash it, will I loose TWRP? I guess no...

4. What is cust.img for? I am more a Samsung guy, not familiar with that file.

Thanks in advance.

 

[reiluke]

i would restore to latest stock rom available and install from there to be safe, careful when wiping boot.img

 

[guiso98]

Thank you...

Here is how I fixed, and put some answers if helpful for anyone else in the future.

1. Bootloader and Boot are different. During the startup process the bootloader calls either boot for a normal startup or call recovery.
Messing with boot won't touch the bootloader or the recovery areas.

2. I did not flash boot at the end, I used the ResurrectionMix which already comes with its own boot image. It took me to Marshmallow (MM).
In theory, this boot image will support any other MM ROM. I did not try because I ended up liking it.

3. As explained in (1). Flashing boot wont touch recovery

4. I haven't found an answer to this one. Anyway, I did not touch it.

Cheers.

 

[reiluke]

boot only contains kernel and ramdisk , recovery its a separate paritition alternative to boot, at startup depending on what is pressed bootloader either calls boot partition or recovery parition or fastboot

 

[itspacific]

Hello
I have honor 5x KIW-L22 & suddenly my mobile shows no service what should i do.
My sim is working in another phone and since i checked in the phone information option while using the ussd code to dispaly the details radio signal button is not showing
in the menu and when i call someone it shows radio off.
Please help me to sort out this.