[U-Boot] [PATCH v2 0/3] Add sdram capacity auto detect for rk3288

[Kever Yang]

Hi Sandy,

On 09/21/2016 08:41 PM, Sandy Patterson wrote:
>
> On Tue, Sep 20, 2016 at 10:56 PM, Kever Yang 
> <kever.yang at rock-chips.com <mailto:kever.yang at rock-chips.com>> wrote:
>
>     parameters changes from dts to auto-detect including those I
>     removed from dts and ddrconfig, stride, they should be the same as
>     without my patch, which means my patch suppose to not change any
>     parameter for DDR other than how we get those parameters.
>
> EARLY_DEBUG was the right idea. Only for some reason it's called 
> EARLY_UART on rk3288.
>
> I tested rock2 and it is getting dbw parameter of 2 instead of 1 for 
> with the unmodified code for both channels. I'm afraid I do not know 
> the significance of this and don't have a good way to test for 
> stability. I am using rock2 square model a with 2gb ram.
>

For LPDDR3, the die bit width(dbw) is fix 2(32bits); and for DDR3 it 
might be dbw=1(16bit, more likely) or dbw=0(8bit), this parameter only 
affect the DRAM tRFC, won't affect the stability but maybe very little 
performance difference if we use smaller die bitwidth.

Thanks,
- Kever
> Sandy