[U-Boot] [PATCH 6/7 v2] OMAP3: Add OMAP3 core changes for MUSB

Wolfgang Denk wd at denx.de
Mon Feb 23 22:36:36 CET 2009


Dear Nishanth Menon,

In message <49A296F0.4000509 at gmail.com> you wrote:
>
> > He probably wants to say that clocks should be enabled only when "usb
> > start" is issued, as you might have u-boot compiled with USB defines
> > set, but never actually use USB.

Correct.

> Comparing having all clock initialization at a central point (clock.c) -
> which seems simple vs having get-put kind of clock apis in U-boot : I

But the explicit rule is only to enable interfaces (and this includes
clocks) when they are actually being used. Enabling all clocks even if
not needed may for example add significantly to the power consumption
and to EMC problems.

> might go for the simple solution of all clocks in a single place..

Please don't.

> u-boot is supposed to "keep it simple", enable/disable clocks on a need
> basis is elegant, though could end up getting extended to i2c and other

Yes, indeed - if you followed the recent discussion about I2C rework
this is indeed under consideration.

> peripherals too(if I were to stretch is pretty hard ;) ).. makes more
> sense in kernel(which is already there) than here - my 2 cents..

Well, we're trying to improve...

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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