Re: [RFC] New target 'cuImage' - compatibility uImage

In message <1154636438.5094.45.camel@localhost> you wrote:

However, currently the zImage has an elfheader which will come before

May it have whatever it wants. It's irrelevant.

WE DO NOT USE zImage FILES FOR U-BOOT.

quoted

This way U-Boot will load (and if necessary  uncompress)  the  kernel
image plus your attached bootstrap code to it's normal start address.
Then  it starts your bootstrap code which can fixup DTB and then just
start the kernel.

We do not need to worry about this with cuImage because the kernel
section will not be compressed. If compression is desired it will be
done at the U-Boot level (were U-Boot would do the uncompressing).

Yes,  we  do  need  to  care  about  this.  A  useless  copy  of  the
uncompressed  kernel  image  is  just  a  waste  of boot time. Not to
mention that you have to copy your bootstrapo loader out of  the  way
before it gets overwritten.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
What is research but a blind date with knowledge?      -- Will Harvey

On Thu, 2006-08-03 at 22:25 +0200, Wolfgang Denk wrote:

In message <1154636438.5094.45.camel@localhost> you wrote:

quoted

However, currently the zImage has an elfheader which will come before

May it have whatever it wants. It's irrelevant.

WE DO NOT USE zImage FILES FOR U-BOOT.

I've explained this well enough at this point, if you don't want to ask
more questions to figure it out then I can not really help anymore.

quoted

quoted

This way U-Boot will load (and if necessary  uncompress)  the  kernel
image plus your attached bootstrap code to it's normal start address.
Then  it starts your bootstrap code which can fixup DTB and then just
start the kernel.

We do not need to worry about this with cuImage because the kernel
section will not be compressed. If compression is desired it will be
done at the U-Boot level (were U-Boot would do the uncompressing).

Yes,  we  do  need  to  care  about  this.  A  useless  copy  of  the
uncompressed  kernel  image  is  just  a  waste  of boot time. Not to
mention that you have to copy your bootstrapo loader out of  the  way
before it gets overwritten.

I agree. Your previous advice is something I am going to try to reduce
memory copying. Keeping the bootloader after the kernel image should
prevent any overwritting problems, as you said.

-Matthew