[U-Boot-Custodians] SPL / TPL

Wolfgang Denk wd at denx.de
Wed Oct 16 16:42:44 UTC 2019

Dear Simon,

In message <CAPnjgZ1vve1yDWXy2it=ShqGqGM6NjpkJVOP=O3ySPM08fObmA at mail.gmail.com> you wrote:
> From my understanding it is more common that we can't load SPL
> directly. E.g. Rockchip uses TPL because the boot ROM cannot load SPL,
> as I understand it.

But this is just because they designed it that way, right?
I know that Heiko is frequently struggeling tokeep SPL size for some
Atmel AT91 based boards below the 4kB limit, but he does not need
any TPL, and if he did, could he not have a small SPL and a bigger

> Let's agree to disagree on this one. I think I've explained how I
> understand it. To me it is it more consistent to down from U-Boot
> backwacks than from the boot rom forwards. U-Boot is always last but
> there are 0, 1, 2 or 3 things before it.

I disagree.  What about Falcon mode, when there is no U-Boot proper
at all? Your counting starts in Nirwana then?

> > * We don't care about the meaning of the names and accept that their
> >   historical meaning may have changed over time.  Then this should
> >   be documented, so we can point to that part of the documentation
> >   when the next such discussion starts.
> >
> > * We try to invent new names for the existing ones and document
> >   these. In this case I strongly oppose any names that suggest some
> >   sort of sequence - no matter if you count in the right or in the
> >   wrong direction ;-)
> >
> >   We could, for example, redefine SPL as "Small Program Loader" and
> >   TPL as "Tiny Program Loader", as this is apparently what most
> >   people in this discussion expect.  [Note that I am not sure that
> >   sizeof(SPL) > sizeof(TPL) for all boards that use both, but this
> >   is probably acceptable for relative terms like "tiny" and
> >   "small".]  If we do this, such re-interpretation needs to be
> >   documented and explained.
> That seems OK to me, and it is at least explainable.


Best regards,

Wolfgang Denk

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