[U-Boot] [PATCH v2 13/22] omap4: add clock support

Wolfgang Denk
2011-05-17T21:44:32Z

Dear Aneesh V,

In message <4DD27893.5000606@ti.com> you wrote:
>
> > It appears this might be part of or taken from some bigger scope
> > clocks framework. Otherwise it's diffcult for me to understand why
> > OMAP4 needs 1400+ lines of code, when other SoCs appear to do with
> > considerably less. Please comment.
>
> No. This code was written for SPL. Please note that a lot of it is
> tables used for PLL locking, clock enabling etc. OMAP4 supports
> different crystal frequencies. So, more entries in each table. Also,
> there are some special handling based on the OMAP4 revisions because of
> some frequency limitations. So, more number of tables.

hm... is this really a type of selection that has to be done at
runtime? In the real system, the frequencies will probably pretty
much fixed, and not dynamically adjusted in U-Boot. So maybe we can
compile at least poarts of this at build time?

> > NAK. We do not accept base address plus offset notation. Please
> > declare C structs instead.
> >
>
> Ok. will do.
>
> Again just curious, what's the reasoning behind this policy? Is it just
> aesthetics or something more?

It's more. When using base+offset, the compiler will know nothing
about the data type, so it canot warn you if you use a 32 bit accessor
on a 8 bit register, or vice versa. When you pass a struct element,
it can check type information.

Best regards,

Wolfgang Denk

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