Re: [PATCH V2 5/7] mmc: sdhci: add CMD23 support for v4 mode

[Adrian Hunter <adrian.hunter@intel.com>]

On 06/15/2018 05:04 AM, Chunyan Zhang wrote:
> Host Driver Version 4.10 adds a new bit in Host Control 2 Register
> for selecting Auto CMD23 or Auto CMD12 for ADMA3 data transfer.

We don't support ADMA3.  It would require changes to the block driver.
So is this change needed?

> 
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
> ---
>  drivers/mmc/host/sdhci.c | 16 +++++++++++++++-
>  drivers/mmc/host/sdhci.h |  1 +
>  2 files changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index b8ee124..3b2af7e 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -954,6 +954,20 @@ static inline bool sdhci_auto_cmd12(struct sdhci_host *host,
>  	       !mrq->cap_cmd_during_tfr;
>  }
>  
> +static inline void sdhci_set_auto_cmd23(struct sdhci_host *host,
> +					struct mmc_command *cmd)
> +{
> +	u16 ctrl2;
> +
> +	if (host->v4_mode) {

Isn't this only for a V4.1 controller, and doesn't the mode have to be "Auto
Cmd Auto Select"?


> +		ctrl2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> +		ctrl2 |= SDHCI_CMD23_ENABLE;
> +		sdhci_writew(host, ctrl2, SDHCI_HOST_CONTROL2);
> +	} else {
> +		sdhci_writel(host, cmd->mrq->sbc->arg, SDHCI_ARGUMENT2);
> +	}
> +}
> +
>  static void sdhci_set_transfer_mode(struct sdhci_host *host,
>  	struct mmc_command *cmd)
>  {
> @@ -989,7 +1003,7 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
>  			mode |= SDHCI_TRNS_AUTO_CMD12;
>  		else if (cmd->mrq->sbc && (host->flags & SDHCI_AUTO_CMD23)) {
>  			mode |= SDHCI_TRNS_AUTO_CMD23;
> -			sdhci_writel(host, cmd->mrq->sbc->arg, SDHCI_ARGUMENT2);
> +			sdhci_set_auto_cmd23(host, cmd);
>  		}
>  	}
>  
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 1e84539..d5e1c10 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -185,6 +185,7 @@
>  #define   SDHCI_CTRL_DRV_TYPE_D		0x0030
>  #define  SDHCI_CTRL_EXEC_TUNING		0x0040
>  #define  SDHCI_CTRL_TUNED_CLK		0x0080
> +#define  SDHCI_CMD23_ENABLE		0x0800
>  #define  SDHCI_CTRL_V4_MODE		0x1000
>  #define  SDHCI_CTRL_64BIT_ADDR		0x2000
>  #define  SDHCI_CTRL_PRESET_VAL_ENABLE	0x8000
>