Re: [PATCH v4 0/7] Add TI EMIF SDRAM controller driver

["Cousson, Benoit" <b-cousson@ti.com>]

+ Felipe,

Hi Paul,

On 4/12/2012 7:00 PM, Paul Walmsley wrote:
> Hi
>
> On Thu, 12 Apr 2012, Mohammed, Afzal wrote:
>
>> On Thu, Apr 12, 2012 at 18:40:45, Greg KH wrote:
>>> On Thu, Apr 12, 2012 at 12:17:49PM +0530, Santosh Shilimkar wrote:
>>>> I was hoping that we will have some thing like drivers/memory/*
>>>> but since it doesn't exist, we used drivers/misc.
>>>
>>> Why not create it?  I have no objection to that, it makes it more
>>> obvious as to what this really is.
>>
>> There is another memory controller used in a few TI SoCs,
>> namely GPMC [1], do you prefer having it too there.
>>
>> As of now it is not a driver, platform code handles GPMC, a patch
>> series for converting it into a driver (but still residing in
>> platform folder) was sent a few days back [2,3].
>
> Probably the GPMC driver should go into a slightly different place than
> SDRC/EMIF.
>
> GPMC is actually a general-purpose parallel bus driver.  It's used to
> interface Ethernet controllers, UARTs, FPGAs, NAND/NOR flash, SRAM, etc.
> It cannot be used to control DRAM, at least not without a separate DRAM
> controller chip.
>
> SDRC/EMIF are both DRAM controllers.  That's all they do.  They can't be
> used to control anything else.  They implement DRAM refresh, etc.

The LPDDR2 spec does consider as well NVM (Non Volatile Memory), so I 
think we should stick to driver/memory for EMIF.

> So perhaps something like drivers/memory/dram/ for the SDRAM controllers,
> and maybe drivers/memory/ for the GPMC?

In fact Felipe was considering something else for that kind of general 
purpose bus driver like GMPC, C2C and LLI...

... But I do not remember the name :-)

Regards,
Benoit