BeagleBoard sdrc init writes reserved values

[Sascha Hauer]

Hi Orjan,

On Wed, Nov 10, 2010 at 09:55:21AM +0100, Orjan Friberg wrote:
> In sdrc_init in board-beagle.c both
>
>         writel(0x1A, SDRC_REG(SYSCONFIG));
>
> and
>
>         writel(0x18, SDRC_REG(SYSCONFIG));
>
> sets bits 4:3 in the IDLEMODE field.  The OMAP3 TRM (spruf98k) defines  
> 0x2 as the only valid value for this field, all others being marked as  
> "reserved - do not use".  board-omap3evm.c does the same thing,  
> board-sdp343x.c does not.
>
> Anyone knows where these settings come from?  Derived from an older  
> version of the TRM?  (I'm thinking there may have been a feature that  
> was discovered to be unreliable or not working as intended so it was  
> removed from the docs.)

I have no idea. I'm pretty sure though that the value has been copied
from some version of U-Boot or Xloader.

Sascha

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