Re: 4.15.0-rc5 fails boot on MX53 LOCO board due to MMC (clock?) issue

["Wladimir J. van der Laan" <laanwj@gmail.com>]

> Can you please try the change below? If it works and everyone is fine
> with it, I will send a proper patch.

Thank you! That fixed the problem.

Tested-by: Wladimir J. van der Laan <laanwj@gmail.com>

> ---
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -687,6 +687,20 @@ static inline void esdhc_pltfm_set_clock(struct
> sdhci_host *host,
>          return;
>      }
> 
> +    /* For i.MX53 eSDHCv3, SYSCTL.SDCLKFS may not be set to 0. */
> +    if (is_imx53_esdhc(imx_data)) {
> +        /*
> +         * According to the i.MX53 reference manual, if DLLCTRL[10] can
> +         * be set, then the controller is eSDHCv3, else it is eSDHCv2.
> +         */
> +        val = readl(host->ioaddr + ESDHC_DLL_CTRL);
> +        writel(val | BIT(10), host->ioaddr + ESDHC_DLL_CTRL);
> +        temp = readl(host->ioaddr + ESDHC_DLL_CTRL);
> +        writel(val, host->ioaddr + ESDHC_DLL_CTRL);
> +        if (temp & BIT(10))
> +            pre_div = 2;
> +    }
> +
>      temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
>      temp &= ~(ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
>          | ESDHC_CLOCK_MASK);