[U-Boot] [U-Boot, v4, 14/19] mmc: dw_mmc: support transfer mode autodetection

[Philipp Tomsich]

On Thu, 17 Aug 2017, Paweł Jarosz wrote:

> dw_mmc supports two transfer modes in u-boot: idma and fifo.
> This patch adds autodetection of transfer mode and eliminates setting this in host config struct
>
> Signed-off-by: Paweł Jarosz <paweljarosz3691 at gmail.com>
> ---
> Changes since v1:
> - none
>
> Changes since v2:
> - none
>
> Changes since v3:
> - none
>
> drivers/mmc/dw_mmc.c | 8 ++++++++
> include/dwmmc.h      | 4 ++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
> index 700f764..2cc4d67 100644
> --- a/drivers/mmc/dw_mmc.c
> +++ b/drivers/mmc/dw_mmc.c
> @@ -428,6 +428,7 @@ static int dwmci_set_ios(struct mmc *mmc)
> static int dwmci_init(struct mmc *mmc)
> {
> 	struct dwmci_host *host = mmc->priv;
> +	uint32_t use_dma;
>
> 	if (host->board_init)
> 		host->board_init(host);
> @@ -439,6 +440,13 @@ static int dwmci_init(struct mmc *mmc)
> 		return -EIO;
> 	}
>
> +	use_dma = SDMMC_GET_TRANS_MODE(dwmci_readl(host, DWMCI_HCON));
> +	if (use_dma == DMA_INTERFACE_IDMA) {
> +		host->fifo_mode = 0;
> +	} else {
> +		host->fifo_mode = 1;
> +	}
> +
> 	/* Enumerate at 400KHz */
> 	dwmci_setup_bus(host, mmc->cfg->f_min);
>
> diff --git a/include/dwmmc.h b/include/dwmmc.h
> index 4dda009..269536d 100644
> --- a/include/dwmmc.h
> +++ b/include/dwmmc.h
> @@ -115,6 +115,10 @@
> #define RX_WMARK_SHIFT		16
> #define RX_WMARK_MASK		(0xfff << RX_WMARK_SHIFT)

Could use GENMASK ...

> +/* HCON Register */
> +#define DMA_INTERFACE_IDMA		(0x0)
> +#define SDMMC_GET_TRANS_MODE(x)		(((x)>>16) & 0x3)

This might be clearer with bitfield_extract from bitfield.h

> +
> #define DWMCI_IDMAC_OWN		(1 << 31)
> #define DWMCI_IDMAC_CH		(1 << 4)
> #define DWMCI_IDMAC_FS		(1 << 3)
>