[U-Boot] uImage load address and entry point with Minnowboard

vinoth eswaran evinoth1206 at gmail.com
Wed Jun 22 16:50:43 CEST 2016


Hello,

 I am working on an embedded project to optimize the boot time on minnowboard.
Currently I am working with the u-boot. With compressed kernel
(bzImage) everything works fine, I want to check the performance with
uncompressed kernel (vmlinux).

I have found that u-boot cannot support the raw vmlinux and I need to
generate the uImage using the u-boot tools.

I tried creating the uImage from the vmlinux --but I did not
understand what does the -a (load address) and -e (entry point )
points to? I assume that it is the same load address used when loading
the kernel image from sd card to RAM.

uImage creation:

mkimage -A x86 -O linux -T kernel -a 0x01000000 -e 0x01000000 -n Linux
-d vmlinux uImage
Image Name:   Linux
Created:      Wed Jun 22 16:31:07 2016
Image Type:   Intel x86 Linux Kernel Image (gzip compressed)
Data Size:    21966248 Bytes = 21451.41 kB = 20.95 MB
Load Address: 01000000
Entry Point:  01000000

Now at start up I am seeing that the kernel is not running, Seeing the
following error messages,

reading uImage
21966312 bytes read in 481 ms (43.6 MiB/s)
Wrong Image Format for bootm command
ERROR: can't get kernel image!

The bootcmd is "bootcmd=fatload mmc 0:1 01000000 uImage ; bootm 01000000"

Do you have any idea why it is happening?

Mit Freundlichen Grüßen
VinothKumar
+49 1798909072


More information about the U-Boot mailing list