> -----Original Message-----
> From: Lucas Stach [mailto:l.stach@pengutronix.de]
> Sent: 2021Äê5ÔÂ11ÈÕ 3:04
> To: Ulf Hansson <ulf.hansson@linaro.org>; Adrian Hunter
> <adrian.hunter@intel.com>; Bough Chen <haibo.chen@nxp.com>
> Cc: Rob Herring <robh+dt@kernel.org>; dl-linux-imx <linux-imx@nxp.com>;
> kernel@pengutronix.de; linux-mmc@vger.kernel.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org
> Subject: [PATCH v2 2/3] mmc: sdhci-esdhc-imx: advertise HS400 mode through
> MMC caps
> 
> Instead of having an indirection through the SDHCI layer and emulating a
> capability bit, that isn't there in hardware, do the same same thing as
with
> HS400_ES and advertise the support for HS400 directly through the MMC
caps.
> 
> Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> ---
>  drivers/mmc/host/sdhci-esdhc-imx.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c
> b/drivers/mmc/host/sdhci-esdhc-imx.c
> index a20459744d21..65a52586db36 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -427,9 +427,6 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int
> reg)
>  					|
FIELD_PREP(SDHCI_RETUNING_MODE_MASK,
>  						     SDHCI_TUNING_MODE_3);
> 
> -			if (imx_data->socdata->flags & ESDHC_FLAG_HS400)
> -				val |= SDHCI_SUPPORT_HS400;
> -
>  			/*
>  			 * Do not advertise faster UHS modes if there are no
>  			 * pinctrl states for 100MHz/200MHz.
> @@ -1603,7 +1600,7 @@ static int sdhci_esdhc_imx_probe(struct
> platform_device *pdev)
>  		host->quirks |= SDHCI_QUIRK_BROKEN_ADMA;
> 
>  	if (imx_data->socdata->flags & ESDHC_FLAG_HS400)
> -		host->quirks2 |= SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400;
> +		host->mmc->caps2 |= MMC_CAP2_HS400;

Hi Lucas,

I think patch1 and patch 2 are enough to cover your requirement.
For this patch, I think it's unnecessary, sdhci-esdhc-imx.c need to reuse
sdhci.c as much as possible.
In sdhci.c, already contain the following logic. 

         if (host->quirks2 & SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400 &&
             (host->caps1 & SDHCI_SUPPORT_HS400))
                 mmc->caps2 |= MMC_CAP2_HS400;

The reason why we directly use host->mmc->caps2 for HS400ES mode is that
sdhci.c do not contain the similar logic.

Adrian, what's your comment?

Best Regards
Haibo
> 
>  	if (imx_data->socdata->flags & ESDHC_FLAG_BROKEN_AUTO_CMD23)
>  		host->quirks2 |= SDHCI_QUIRK2_ACMD23_BROKEN;
> --
> 2.31.1