[U-Boot-Users] possible problem in u-boot-0.2.0/cpu/mpc8xx/cpu_init.c

[Wolfgang Denk]

In message <00eb01c2ccf7$3b7bc230$6d4ba8c0 at alb.sub.de> you wrote:
> 
> I am just porting u-boot to our TOP860 module, which uses 50MHz/80Mhz
> core clock and 25MHz/40MHz Bus Clock (EBDF=1).

Is your HRCW set that way, too?

> I noticed that in cpu_init.c/line 77ff the PLPRCR is written before SCCR
> which will cause the CLKOUT to ramp up to 50 MHz before it is being
> reduced to half the frequency. That might violate alot of timings. It
> does not appear to cause any problems right now; but I would suggest
> anyway to change the order there.

You are not supposed to change the EBDF setting. The code reads:

    ...
     90  
     91         /* System integration timers. Don't change EBDF! (15-27) */
     92  
    ...


Best regards,

Wolfgang Denk

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