[U-Boot-Users] CFG_HZ value

Wolfgang Denk wd at denx.de
Wed Jun 20 09:27:28 CEST 2007


In message <87A697E50899F541B77272C331CEB744D502 at exchange.Q-DOMAIN> you wrote:
> 
> How should one define CFG_HZ?  It seems that it's to be set to 1000.

Correct. Please consider CFG_HZ as a constant which has to be set to
1000 on all systems.

> However my system clock speed is not this.  What are the rules for

It has nothing to do  with  any  clock  speed,  like  the  time  unit
(seconds)  on  you  digital  watch  has nothing to do with the actual
clock of the quartz used somewhere in it.

> Should I replace the CFG_HZ with my real system clock speed?  BTW, I

No. CFG_HZ is always 1000.

> have to read a register at boot time to determine what speed I am
> running at.  I do this early on and save a variable 'clock_speed' that
> other functions can use to determine the system clock speed.

With correctly implemented timer functions it just works.

> ------_=_NextPart_001_01C7B2DA.91121226
> Content-Type: text/html;

Please never post HTML here.

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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