CPU frequency

Dear All,

As far as I know, the board is clocked at 400Mhz, and the specs report a
maximum speed at 533MHz.
Did someone try to use a higher clock? The onboard quartz is a 12MHz one.
Looking in Samsung S3C2440 datasheet page 255 (7-21) it is possible to set
clock speed at 532MHz with a 12MHz input quartz by setting MDIV to 0x7D,
PDIV=1 and SDIV=1.

I wondered if it was possible to write a driver to change CPU speed on the
fly or if this should be done in the boot firmware.

Any ideas?

Thx

Hey,

It should be possible on the fly as samsung suggests frequency scaling
and/or voltage scaling for power management.

Thank you,
Errol

Hi,
Does anyone know where to make these changes in kernel code ?

Is there anything with CONFIG_HZ parameter in kernel config ?

If you read a current datasheet of the S3C2440 CPU they are specified for
400 MHz only.

AFAIK you can use U-boot to set the cpu frequency at boot time.

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