[U-Boot] [PATCHv5 09/14] mmc: support the DDR mode for eMMC

[Hector Palacios]

On 05/21/2014 04:20 AM, Jaehoon Chung wrote:
> Hi, Hector.
>
> On 05/21/2014 01:37 AM, Hector Palacios wrote:
>> Hi,
>>
>> On 05/16/2014 06:59 AM, Jaehoon Chung wrote:
>>> Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
>>> Tested-by: Lukasz Majewski <l.majewski at samsung.com>
>>> Acked-by: Lukasz Majewski <l.majewski at samsung.com>
>>
>> What platforms did you test DDR mode on?
>
> I have tested DDR mode with exynos board.
>
>> I tried this on an Freescale i.MX6 based platform but the driver returned error code COM_ERR (-18) when trying to switch to any of the DDR modes. I guess the fsl_esdhc.c driver needs some adaptation for DDR to work.
>
> I didn't know how work DDR mode at fsl_esdhc.c.(If you share the host controller TRM, it's helpful to me.)
> Host controller also need to change the DDR mode.
>
> I wonder your board didn't work not to enable the DDR mode?

Thank you, yes the fsl_esdhc.c driver does not yet support enabling of DDR mode.
I think it should be easy to implement, I believe it is just a question of changing 
the clock frequency.

Best regards,
--
Hector Palacios