PLL & clock settings on GTA02: u-boot vs. qi

scholbert scholbert at
Thu Feb 5 18:24:52 CET 2009

Andy Green wrote:
> Little bit more on this in case you're lacking the datasheet... you need
> to crank the CPU core LDO DOWN1 to 1.7V according to the datasheet to
> get "around 500MHz".  So it would be (in src/cpu/s3c2442/gta02.c)
> - -	{ PCF50633_REG_DOWN1OUT,	0x1b }, /* 1.3V (0x1b * .025V + 0.625V) */
> +       { PCF50633_REG_DOWN1OUT,	43 }, /* 1.7V (43 * .025V + 0.625V) */
> It's this that really hurts it on power consumption.
> Another idea, the memory voltage of nominal 1.8V generated by DOWN2 can
> be cranked to max 1.95V, this may help go past 100MHz.
> It'd be very cool if it was possible to overclock the thing.
Yeah that's true and i'm sure it's possible!
Thanks for the additional hints, by the way i got all that datasheets.

Though i'm familiar with these tiny little chips and devices (although it's
more hardware related) and really like such experiments, my sparetime is
very limited to allow such overclocking experiments at the moment, i'm
afraid ;-).
Additionally i'm just in the process of increasing usability of my GTA02 to
use it everyday......
... so perhaps i should stick a bit to the higher level right now.

Anyway i just started this thread and i'm a curious guy, so never say never.



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