NOTE: Instructions are terse and intended towards developers for now.
Standard disclaimer, I am not liable if you brick your fire.
- working adb, (on windows) with the additional %SingleBootLoaderInterface% entry mentioned
- working fastboot binary that recognizes / allows specifying the vendor id (0x1949)
- root. it may work without, but you probably want or have it already
- boot.img from the latest sw update.
- get a adb shell
- use the '/system/bin/idme' command to set the bootmode. I suggest you first run 'idme ?' and write down your default, mine is "4000 0".
- if you set bootmode to 0x4002, the fire will stay in fastboot mode when it reboots
- if you set bootmode to 0x4003, it's supposed to timeout from fastboot mode, but I did not have much luck getting a normal boot after the timeout (did not play too much here).
- if you decide you dont want fastboot mode, run 'idme bootmode "4000 0"' to reset back to default for normal booting.
IF YOU REBOOT AT THIS POINT THE FIRE WILL BE IN THE FASTBOOT MODE. I HAVE NOT FOUND A WAY TO EXIT THIS MODE AND RETURN TO THE NORMAL OS WITHOUT A WORKING FASTBOOT CLIENT.
YOU MAY BE BRICKED IF YOU DONT HAVE WORKING TOOLS.
When you boot into fastboot mode, it will show the "Kindle Fire" logo. The power button does not appear to do anything; therefore, if you boot a bad kernel/image it may get stuck and require a hard reset (pulling the battery cable).
You should now have access to the standard flashboot functionality (update, flash, usb boot, etc). Note that reboot-bootloader will bring you back to fastboot.
I currently use 'fastboot boot boot.img' (from the sw update) to get back to a working state. Once booted, use idme to disable fastboot.
Now, on to recovery's & custom roms!