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aholmes5 · 12-03-2019, 09:53 AM

For kindles that can't be downgraded via a Factory image, would the following commands work or would this destroy the kindle? This is what I did to restore an PW2 to 5.4.0.

1) Extract the older firmware image with KindleTool to /mnt/us.
2) Boot to rescue partition using rescue pack or serial port and exit to command prompt.
3) Run: zcat /mnt/us/mmcblk0p1.bin.gz| dd of=/dev/mmcblk0p1 bs=4096
4) Run: dd if=/mnt/us/main_kernel.img of=/dev/mmcblk0 bs=4096 seek=65
5) Might need an "echo 0 > /var/local/upstart/lab126_gui.restarts
6) Reboot: idme -d --bootmode main && reboot
7) Hopefully reboots into older firmware then do a reset device from main menu.
8) Rejailbreak with factory JB or serial.

12-03-2019, 09:53 AM	#1
aholmes5 Member Posts: 22 Karma: 498 Join Date: Nov 2013 Device: PW2, PW3, PW4, PW5	Manual firmware downgrade from shell For kindles that can't be downgraded via a Factory image, would the following commands work or would this destroy the kindle? This is what I did to restore an PW2 to 5.4.0. 1) Extract the older firmware image with KindleTool to /mnt/us. 2) Boot to rescue partition using rescue pack or serial port and exit to command prompt. 3) Run: zcat /mnt/us/mmcblk0p1.bin.gz\| dd of=/dev/mmcblk0p1 bs=4096 4) Run: dd if=/mnt/us/main_kernel.img of=/dev/mmcblk0 bs=4096 seek=65 5) Might need an "echo 0 > /var/local/upstart/lab126_gui.restarts 6) Reboot: idme -d --bootmode main && reboot 7) Hopefully reboots into older firmware then do a reset device from main menu. 8) Rejailbreak with factory JB or serial.