[U-Boot-Users] [PATCH] add OpenGear CM4008 board support

Wolfgang Denk
2005-05-20T14:45:49Z

Dear Greg,

in message <428DF0F8.5090404@moreton.com.au> you wrote:
>
> The gofsk command is something I added to support loading
> snapgear/uClinux-dist style raw filesystem+kernel images.

I don't understand why a separate command is needed for that; you
need to store the start address of the image anyway, so you can also
store it's size and use this to compute any other offset; or store
the kernel address, too.

> The image itself is a simple concatenation of a root filesystem
> and a kernel. Typically it is used with a CRAMfs root filesystem.
> The primary motivator for not having any header on this image is
> that it can be dumped directly into an MTD flash partition, and
> it can be directly mounted as the root filesystem. For known

This is normal. We don't have headers for standard filesystem images
like cramfs, ext2 or jffs2 for exactly this reason.

> filesystem types (like CRAMfs and ROMfs) the loader simply looks
> over the filesystem to get to the kernel for boot time starting.

Why do you need a separate command for this?

> Patch attached is my current implementation of this.
>
> Is this something that you would allow into the main tree?

No, I don't think so. I don't see what it gives you what you cannot
get with the existing commands and clever usage of a few environment
variables. Also, in general I find it is not a good idea to combine
filesystem and OS kernel into ane image. Usually you buy more
restrictions than advantages this way. If you feel you must do it,
you could extend the capabilities of mutli-file images to match your
needs.

But the main question is: what can you do with this setup that cannot
be done with the existing code, too?

Best regards,

Wolfgang Denk

--
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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