[U-Boot] [PATCH] sunxi: makes an invisible option for H3-like DRAM controllers

[Icenowy Zheng]

2017年1月9日 下午7:06于 Maxime Ripard <maxime.ripard at free-electrons.com>写道：
>
> On Fri, Jan 06, 2017 at 07:13:17AM +0800, Icenowy Zheng wrote: 
> > 
> > 
> > 06.01.2017, 06:16, "Maxime Ripard" <maxime.ripard at free-electrons.com>: 
> > > On Thu, Dec 29, 2016 at 02:50:48AM +0800, Icenowy Zheng wrote: 
> > >>  Allwinner SoCs after H3 (e.g. A64, H5, R40, V3s) uses a H3-like 
> > >>  DesignWare DRAM controller, which do not have official free DRAM 
> > >>  initialization code, but can use modified dram_sun8i_h3.c. 
> > >> 
> > >>  Add a invisible option for easier DRAM initialization code reuse. 
> > > 
> > > Since it's used on all the newer SoCs, do we need to keep the H3 name 
> > > in the config option name? 
> > 
> > Good question... 
> > 
> > Name it "SUNXI_DW_DRAM"? 
>
> Looks good. 
>
> > (Although I think at least A33 uses the same series of DRAM controller) 
>
> Does it? Why do we need a separate DRAM init code then? 

I think it does. See dram_sun8i_a33.c .

We used to use per-device dram code, but failed after allwinner uses libdram, then we worked on modifying H3 code.

I think it's also possible to make H3 code 
capable of A33, but since our A33 code works well, should we do it?

>
> Thanks, 
> Maxime 
>
> -- 
> Maxime Ripard, Free Electrons 
> Embedded Linux and Kernel engineering 
> http://free-electrons.com