[U-Boot-Users] [Patch]New board support : lite_dw

[Wolfgang Denk]

Dear Sam,

sorry for the delay.

In message <20040504010903.79934.qmail at web15212.mail.bjs.yahoo.com> you wrote:
>
> > > 2. 64MHz/48MHz system clock options;
> > If possible, make it automatically detect  the 
> > clock  frequency  and  auto-adjust.  Your  users  
> > will  praise  you if the same binary image
> > works on both configurations.
> 
> This is really a challenge for me.I meant to build two
> targets for it and did.How to make it?Usually we set
> PLPRCR in <board.h> to choose system clock for board
> init.It seems that it's programmers to decide the
> value according to CPU max frequency and oscillator's
> frequency on the board.Any clue with it?

How do you you initialize your HRCW? Again, you can check the TQM8xxL
boards to see how to deal with differing  clock  configurations;  you
can  even  allow  the  user  to  adjust the clock frequency using the
"cpuclk" environment variable.

> > > 3. ENV_IS_IN_FLASH/ENV_IS_IN_NVRAM;
> > 
> > Either make it a  different  build  targets,  or 
> > select  a  standard configuration  and  let  the  
> > user  decide to modify the board config file.
> 
> I really want to make the second possible.Did u-boot
> command do this job?

I recommend to provide a default configuration which uses environment
in flash; you  provide  the  second  option  (environment  in  NVRAM)
commented  out  ("#  if 0" or so) in the config file, so the user can
enable it if he likes so.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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