Use fastboot to boot from USB?

[cwalls]

Is it possbile to use https://github.com/yifanlu/Fastboot-Kindle in order to boot a custom kernel from USB (aka without flashing it?) I tried './fastboot boot uBoot' and './fastboot boot vmlinux', but I think it just booted (after downloading) the normal kernel:

downloading
done
## Booting kernel from Legacy Image at 80800000 ...
   Image Name:   Linux-3.0.35-lab126
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    3143456 Bytes =  3 MB
   Load Address: 80008000
   Entry Point:  80008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK

Btw './fastboot flash kernel' worked fine.

I saw the thread "How-to: Booting U-Boot and Linux over USB", but I think activating the "Serial Download Protocol" (SDP) would require me to unscrew the board again, which I would like to avoid if possible. (Also I wasn't able to find TM401, only "TM501 BOOT_0", see here, nor CR501 here).
I feel like erasing the first 128kB of mmcblk0boot0 is not the safest method/idea, even though it might would work out all just fine!

Thanks!

[katadelos]

Originally Posted by cwalls

Is it possbile to use https://github.com/yifanlu/Fastboot-Kindle in order to boot a custom kernel from USB (aka without flashing it?) !

Not that I'm aware of, though I haven't experimented too much with this. It's definitely not happening in that snippet that you shared - the message you see there is from a uImage wrapper around a kernel image.

Originally Posted by cwalls

I saw the thread "How-to: Booting U-Boot and Linux over USB", but I think activating the "Serial Download Protocol" (SDP) would require me to unscrew the board again, which I would like to avoid if possible. (Also I wasn't able to find TM401, only "TM501 BOOT_0", see here, nor CR501 here).
I feel like erasing the first 128kB of mmcblk0boot0 is not the safest method/idea, even though it might would work out all just fine!

TM501 is indeed the test point that you want for a KV, I'll update that post when I get the chance. Deleting the first 128K is safe, the scary warning is there to stop people from nuking the entire partition and losing their idme variables in the process.

[eddie.t.h]

Originally Posted by katadelos

Deleting the first 128K is safe, the scary warning is there to stop people from nuking the entire partition and losing their idme variables in the process.

AFAIK idme variables are stored in the RPMB area of memory and are unlikely to be accidentally deleted.