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

[Fabio Estevam]

Hi Benoît,

On Wed, Oct 18, 2017 at 2:13 PM, Benoît Thébaudeau <benoit at wsystem.com> wrote:

> You could stress-test the SD read/write accesses from U-Boot. Does it occur with
> all HS cards?

I am not able to run a stress-test because all SD card accesses fail.

It happens with all HS cards I tested with.

> 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.

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?

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

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.

Thanks