Thread: It is possible replace u-boot & uImage ?
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Old 08-22-2017, 02:43 PM   #4
knc1
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Quote:
Originally Posted by yabba235 View Post
Hi !
I spend long time for answer for simple question:
my KV has upgrade to 5.8.10 so I can't downgrade to fw 5.5.0 and jb etc.
But I thinking this happen because newest uboot/uImage blocking update initial fw.
So maybe is possible replace new uboot/uImage with older version exstracted from eg. fw 5.6.5 and downgrade to fw 5.5.0 ??

Do I think right ?
No, you do not think right.

U-Boot has nothing to do with OTA updates or image update installation.
The initramfs portion of the kernel portion of uImage has one of the OTA updaters.
You will have to decompile and study it.

The other OTA updater is in the 'main' system.
You can just mount the rootfs image from an Amazon update package and study it.

= = = =

But before you waste too much of your lifetime on all of that -
Think this through:
"If we (or you) could write something to the device's storage, don't you think we would just write the 250 byte signature certificate and be done with it all?"

(Which is what coplate said above - if we could write a new u-boot, then we could also write a new (our) signature certificate.)
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