No console output when booting linux from uboot

Detlev Zundel dzu at
Fri Jun 6 00:22:04 EST 2008

Hi Mike,

> Thanks. Now I am confusing with the way uboot passing parameters to
> linux kernel:
> in Uboot 1.2.0: Kernel is entered through the following calling
>         theKernel (linux_argc, linux_argv, linux_env, 0);
> while in Uboot 1.3.0:
>         (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
> The linux kernel I used is designed with Uboot 1.2.0, while I used
> 1.3.2. Will this be a problem for passing the parameters?

Hm, now you got me confused.  I cannot see the first version anywhere in
u-boot or its history.  Even in 1.2.0 its either

(*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);


(*kernel) ((bd_t *)of_flat_tree, (ulong)kernel, 0, 0, 0);

The first path is chosen when using the traditional 2 argument bootm
command, the logic being that this is a non-fdt aware kernel.  The
second path is chosen when using the newer three-argument version of
bootm with the third argument being the flat device tree (needs
CONFIG_OF_FLAT_TREE in U-Boot 1.2.0).

So if you have anything differing from this, you have to conclude for
yourself what the situation is.  When you have mainline U-Boot and Linux,
i.e. comparable what I describe, we especially took care that we are
backwards compatible.  So by using the two- or three parameter version,
we effectively select between two kernel call conventions.  The
situation stays the same in newer U-Boot versions.


DENX Software Engineering GmbH,      MD: Wolfgang Denk & Detlev Zundel
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Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at

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