[yocto] uimage instead of zImage

Wolfgang Denk wd at denx.de
Sun Oct 27 01:39:31 PDT 2013

Dear Edward,

In message <CANwz6nzQq8a1RnqL3Ety2tJ-CkTOnOObQtiEVXu6+TOhve5LAA at mail.gmail.com> you wrote:
> A uImage file is a kernel with a modified header for u-boot. A tool called

No header gets modified.  Instead, a new header gets prepended.

> mkimage is used to convert a zImage (regular kernel compressed image) to a

Actually it's pretty stupid to use a zImage inside an uImage.  It is
much better to use normal (uncompressed) kernel image, compress it
using just gzip, and use this as poayload for mkimage.  This way
U-Boot does the uncompresiong instead of including yet another
uncompressor with each kernel image.

> uImage file. And No, zImage files, as they are, are not compatible with
> U-Boot. You must convert them

You can boot zImage files directly with U-Boot.  That's what the
"bootz" command is for.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Hacking's just another word for nothing left to kludge.

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