Correct S3C2442B core voltages (Was: PLL & clock settings on GTA02: u-boot vs. qi)

Rask Ingemann Lambertsen rask at
Sun Apr 5 17:52:31 CEST 2009

On Thu, Feb 05, 2009 at 03:45:26PM +0000, Andy Green wrote:
> Hash: SHA1
> Somebody in the thread at some point said:
> | It sounds great if you want to meddle with this.  One hidden possibility
> | you might not be aware of is that the CPU is actually 500MHz-capable
> | according to the datasheet, I think the part codes claim 533MHz.
> 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) */

   My copy of the datasheet is revision 1.2, which is obviously out of date,
as in table 25-2, "DC Supply Voltage for Internal" lists 1.50 V for 400 MHz
where we use 1.3 V and there's no mention of running at more than 400 MHz.
Can I have the correct voltages for the other frequencies as well?

Rask Ingemann Lambertsen
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