Imx6ull kernel load time


I’ m trying to speed up boot time and noticed that loading the kernel takes a lot of time:
[2.039394 0.001543] Read 5616192 bytes from volume kernel to 81000000
[6.389443 4.350049] No size specified → Using max size (52395)

Is the Read speed bound by the nand or bound by cpu speed?

Is there a patch available for uboot to run at 528 instead of 396 Mhz and/or speed up the nand?

Compared to a vf50 colibri the kernel takes forever to load, i don’t understand the big speed difference.

I’m running U-Boot 2020.07-5.3.0-devel+git.68f97c8d17f0 (Jun 24 2021 - 07:52:49 +0000)
from the Reference-Minimal-Image-colibri-imx6ull

Best Regards,

Hello @vincent ,

Yes, it is indeed possible to speed up the and for maximum utilization. Please refer to this thread where a similar issue is discussed:

Does this help?

BR, Janani


Yes I saw it and did the modification in uboot, it boots a lot faster now; comparable to the vf50.

Kernel load time:
[1.053392 0.021171] Read 5616080 bytes from volume kernel to 81000000
[2.475176 1.421784] No size specified → Using max size (52395)

Is there going to be an official patch for uboot?


Hello @vincent ,

no, not as far as I know. As not all customers require this special feature.

BR, Janani