[U-Boot] [RFC] mmc: fsl_esdhc: Do not set high speed mode on MX25 and MX51

[Benoît Thébaudeau]

Hi Fabio,

On 18/10/2017 at 18:40, Fabio Estevam wrote:
> On Wed, Oct 18, 2017 at 2:13 PM, Benoît Thébaudeau <benoit at wsystem.com> wrote:
>> You can try to set the drive strength of all the eSDHC pads to high or max (for
> 
> Looks like the eSDHC pins do not have drive strength control, only
> PKE, PUE, PUS and SRE fields.

They may also be in a pad group control register such as
MX25_PAD_CTL_GRP_DSE_CSI.

> Also, in the kernel I do not do pinctrl setting and just use the IOMUX
> values from U-Boot. In the kernel the SD card operation in high speed
> works fine.
> 
>> each pad or for the group of pads depending on the register layout for the pads
>> used on the board). This worked on my board (custom i.MX25-based, not imx25pdk).
> 
> Could you please share your custom eSDHC pinctrl settings in U-Boot?

I can tell you what to use for imx25pdk if you give me the pads used by the
eSDHC instance in question here.

> Also, I suppose you see "Tran Speed: 50000000" when you run mmc info
> with a SD high speed card connected.

Indeed.

> In my case whenever 'mmc info' reports 50MHz I am not able to access
> the SD card (saveenv, for example) on both mx25pdk and mx51evk.

Note that I am using a modified version of U-Boot, so it may work thanks to that
for me, but the pad fixup was required anyway.

Best regards,
Benoît