[PATCH v5 1/3] mmc: sdhci: Add HS400 Enhanced Strobe support

[Kever Yang]

HI Alper,

On 2022/3/16 01:46, Alper Nebi Yasak wrote:
> Delegate setting the Enhanced Strobe configuration to individual drivers
> if they set a function for it. Return -ENOTSUPP if they do not, like
> what the MMC uclass does.
>
> Signed-off-by: Alper Nebi Yasak <alpernebiyasak at gmail.com>
> Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>
Reviewed-by: Kever Yang <kever.yang at rock-chips.com>

Thanks,
- Kever

> ---
>
> (no changes since v4)
>
> Changes in v4:
> - Add comment for SDHCI set_enhanced_strobe() operation
>
> Changes in v2:
> - Add tag: "Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>"
>
>   drivers/mmc/sdhci.c | 18 ++++++++++++++++++
>   include/sdhci.h     | 12 ++++++++++++
>   2 files changed, 30 insertions(+)
>
> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> index 766e4a6b0c5e..bf989a594f7e 100644
> --- a/drivers/mmc/sdhci.c
> +++ b/drivers/mmc/sdhci.c
> @@ -513,6 +513,7 @@ void sdhci_set_uhs_timing(struct sdhci_host *host)
>   		reg |= SDHCI_CTRL_UHS_SDR104;
>   		break;
>   	case MMC_HS_400:
> +	case MMC_HS_400_ES:
>   		reg |= SDHCI_CTRL_HS400;
>   		break;
>   	default:
> @@ -666,6 +667,7 @@ static int sdhci_set_ios(struct mmc *mmc)
>   		    mmc->selected_mode == MMC_DDR_52 ||
>   		    mmc->selected_mode == MMC_HS_200 ||
>   		    mmc->selected_mode == MMC_HS_400 ||
> +		    mmc->selected_mode == MMC_HS_400_ES ||
>   		    mmc->selected_mode == UHS_SDR25 ||
>   		    mmc->selected_mode == UHS_SDR50 ||
>   		    mmc->selected_mode == UHS_SDR104 ||
> @@ -799,6 +801,19 @@ static int sdhci_wait_dat0(struct udevice *dev, int state,
>   	return -ETIMEDOUT;
>   }
>   
> +#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
> +static int sdhci_set_enhanced_strobe(struct udevice *dev)
> +{
> +	struct mmc *mmc = mmc_get_mmc_dev(dev);
> +	struct sdhci_host *host = mmc->priv;
> +
> +	if (host->ops && host->ops->set_enhanced_strobe)
> +		return host->ops->set_enhanced_strobe(host);
> +
> +	return -ENOTSUPP;
> +}
> +#endif
> +
>   const struct dm_mmc_ops sdhci_ops = {
>   	.send_cmd	= sdhci_send_command,
>   	.set_ios	= sdhci_set_ios,
> @@ -808,6 +823,9 @@ const struct dm_mmc_ops sdhci_ops = {
>   	.execute_tuning	= sdhci_execute_tuning,
>   #endif
>   	.wait_dat0	= sdhci_wait_dat0,
> +#if CONFIG_IS_ENABLED(MMC_HS400_ES_SUPPORT)
> +	.set_enhanced_strobe = sdhci_set_enhanced_strobe,
> +#endif
>   };
>   #else
>   static const struct mmc_ops sdhci_ops = {
> diff --git a/include/sdhci.h b/include/sdhci.h
> index c8d69f5a63f7..88f1917480b6 100644
> --- a/include/sdhci.h
> +++ b/include/sdhci.h
> @@ -272,6 +272,18 @@ struct sdhci_ops {
>   	int (*platform_execute_tuning)(struct mmc *host, u8 opcode);
>   	int (*set_delay)(struct sdhci_host *host);
>   	int	(*deferred_probe)(struct sdhci_host *host);
> +
> +	/**
> +	 * set_enhanced_strobe() - Set HS400 Enhanced Strobe config
> +	 *
> +	 * This is called after setting the card speed and mode to
> +	 * HS400 ES, and should set any host-specific configuration
> +	 * necessary for it.
> +	 *
> +	 * @host: SDHCI host structure
> +	 * Return: 0 if successful, -ve on error
> +	 */
> +	int	(*set_enhanced_strobe)(struct sdhci_host *host);
>   };
>   
>   #define ADMA_MAX_LEN	65532