[U-Boot] rk3188/rock_defconfig sdmmc failures

[Heiko Stübner]

Hi Artturi,

Am Mittwoch, 6. September 2017, 01:50:38 CEST schrieb Artturi Alm:
> So, being optimistic, i added compatible found from
> arch/arm/dts/rk3xxx.dtsi, included by rk3188:
> 
> diff --git a/drivers/mmc/rockchip_dw_mmc.c b/drivers/mmc/rockchip_dw_mmc.c
> index e7fcf89..a879fcd 100644
> --- a/drivers/mmc/rockchip_dw_mmc.c
> +++ b/drivers/mmc/rockchip_dw_mmc.c
> @@ -160,6 +160,7 @@ static int rockchip_dwmmc_bind(struct udevice *dev)
> 
>  static const struct udevice_id rockchip_dwmmc_ids[] = {
>         { .compatible = "rockchip,rk3288-dw-mshc" },
> +       { .compatible = "rockchip,rk2928-dw-mshc" },
>         { }
>  };

The rk3188 SPL is using OF_PLATDATA which transforms the devicetree entry
into a struct during compilation to save space in the image.
Relevant to this would be the U_BOOT_DRIVER below that compatibles, which
currently binds to the rockchip_rk3288_dw_mshc transformed compatible.

Adding a second U_BOOT_DRIVER entry there might help for the probing,
but seeing that the dw-mmc in the Linux kernel behaves differently for
rk3188 and rk3288 onwards, I'm not sure if it would work out of the box.

[...]

> now i've "successfully" enabled usb, but it took like +30tries
> w/"usb reset" until the host ports succesfully found my usb mass storage,
> and sometimes it leaves the dwc2 otg controller in a state where
> "usb tree" will fault while printing out, and reset the board, so i'd
> rather have sdmmc working for now instead, as it is enabled already in
> the default config for the board.

For usb you might want to make sure the usb host regulator is enabled
I have the below commands in my netboot uboot for the rock and it is
working quite reliable and so far I haven't seen usb-related issues there.

regulator dev host-pwr;
regulator enable;
usb start;


Hope that helps a bit
Heiko