[U-Boot] Skipping relocation RAM to RAM, esp. on i.MX6?

[Wolfgang Denk]

Dear Aneesh V,

In message <4F3219A8.7090607 at ti.com> you wrote:
> 
> As for ignoring comments, I think you are culpable of that more than me
> in this specific instance:) (of course I know you are busy person, but
> still..). For instance, my arguments in the previous round [1] never
> got an answer from you.
> 
> [1] http://article.gmane.org/gmane.comp.boot-loaders.u-boot/96371

I don't see any question from you that has not been answered?

You suggest to do things in a way that introduces a number of
often discussed disadvantages.  And you claim that for you this would
be good enough.  What should I comment on this?

For the record:

- You continiue to talk about relocation, but you mean something
  different (a memory copy).  I am not sure if you really understand
  the difference.

- You claim omitting this copy operation would be important to
  optimize boot times, but you cannot provide any real numbers that
  support such a claim:

  * You do not know how much time exactly is needed for this copy
    operation, so you don't know how much you can potentially safe,
    and if this would result in any perceptible imprvement of the boot
    time.

  * You did not investigate how long other parts of the boot process
    are talking, so you don't really know where the hot spot where you
    should focus your optimization efforts.

  * You did not investigate how the timing behaviour changes if you
    enable both instruction and data cache in the SPL. In my
    experience this would be a way more rewarding target for
    optimization efforts than omitting a little memcpy().

Best regards,

Wolfgang Denk

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