[PATCH 10/14] spi: dw: Add DUAL/QUAD/OCTAL caps

[Sean Anderson <seanga2@gmail.com>]

On 1/31/21 7:34 PM, Sean Anderson wrote:
> These capabilities correspond to SSIC_SPI_MODE of 1, 2, or 3, respectively.
> This doesn't do much yet, but it does add support for detection and for
> disallowing unsupported modes.  Unfortunately, we cannot discriminate
> between these modes (only that SSIC_SPI_MODE != 0), so we only assume DUAL
> if something sticks to SPI_FRF.
> 
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> ---
> 
>   drivers/spi/designware_spi.c | 41 +++++++++++++++++++++++++-----------
>   1 file changed, 29 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c
> index 683394a5a4..1dd83e6ca6 100644
> --- a/drivers/spi/designware_spi.c
> +++ b/drivers/spi/designware_spi.c
> @@ -129,6 +129,9 @@ struct dw_spi_priv {
>   #define DW_SPI_CAP_KEEMBAY_MST		BIT(1) /* Unimplemented */
>   #define DW_SPI_CAP_DWC_SSI		BIT(2)
>   #define DW_SPI_CAP_DFS32		BIT(3)
> +#define DW_SPI_CAP_DUAL			BIT(4)
> +#define DW_SPI_CAP_QUAD			BIT(5)
> +#define DW_SPI_CAP_OCTAL		BIT(5)

Looks like these CAPs both use BIT(5). Will fix in next revision.

Actually, it might be better to just have a CAP_EXTENDED and let the SPI
slave determine the bus width...

--Sean

>   	unsigned long caps;
>   	unsigned long bus_clk_rate;
>   	unsigned int freq;		/* Default frequency */
> @@ -141,6 +144,7 @@ struct dw_spi_priv {
>   	u8 cs;				/* chip select pin */
>   	u8 tmode;			/* TR/TO/RO/EEPROM */
>   	u8 type;			/* SPI/SSP/MicroWire */
> +	u8 spi_frf;			/* BYTE/DUAL/QUAD/OCTAL */
>   };
>   
>   static inline u32 dw_read(struct dw_spi_priv *priv, u32 offset)
> @@ -267,7 +271,6 @@ static void spi_hw_init(struct udevice *bus, struct dw_spi_priv *priv)
>   		priv->fifo_len = (fifo == 1) ? 0 : fifo;
>   		dw_write(priv, DW_SPI_TXFTLR, 0);
>   	}
> -	dev_dbg(bus, "fifo_len=%d\n", priv->fifo_len);
>   }
>   
>   /*
> @@ -351,22 +354,21 @@ static int dw_spi_probe(struct udevice *bus)
>   	if (ret)
>   		return ret;
>   
> -	priv->caps = dev_get_driver_data(bus);
> -	dw_spi_detect_caps(bus, priv);
> -
> -	version = dw_read(priv, DW_SPI_VERSION);
> -	dev_dbg(bus, "ssi_version_id=%c.%c%c%c ssi_max_xfer_size=%u\n",
> -		version >> 24, version >> 16, version >> 8, version,
> -		priv->caps & DW_SPI_CAP_DFS32 ? 32 : 16);
> -
>   	/* Currently only bits_per_word == 8 supported */
>   	priv->bits_per_word = 8;
>   
>   	priv->tmode = 0; /* Tx & Rx */
>   
>   	/* Basic HW init */
> +	priv->caps = dev_get_driver_data(bus);
>   	spi_hw_init(bus, priv);
>   
> +	version = dw_read(priv, DW_SPI_VERSION);
> +	dev_dbg(bus,
> +		"ssi_version_id=%c.%c%c%c ssi_rx_fifo_depth=%u ssi_max_xfer_size=%u\n",
> +		version >> 24, version >> 16, version >> 8, version,
> +		priv->fifo_len, priv->caps & DW_SPI_CAP_DFS32 ? 32 : 16);
> +
>   	return 0;
>   }
>   
> @@ -748,13 +750,25 @@ static int dw_spi_set_mode(struct udevice *bus, uint mode)
>   {
>   	struct dw_spi_priv *priv = dev_get_priv(bus);
>   
> +	if (!(priv->caps & DW_SPI_CAP_DUAL) &&
> +	    (mode & (SPI_RX_DUAL | SPI_TX_DUAL)))
> +		return -EINVAL;
> +
> +	if (!(priv->caps & DW_SPI_CAP_QUAD) &&
> +	    (mode & (SPI_RX_QUAD | SPI_TX_QUAD)))
> +		return -EINVAL;
> +
> +	if (!(priv->caps & DW_SPI_CAP_OCTAL) &&
> +	    (mode & (SPI_RX_OCTAL | SPI_TX_OCTAL)))
> +		return -EINVAL;
> +
>   	/*
>   	 * Can't set mode yet. Since this depends on if rx, tx, or
>   	 * rx & tx is requested. So we have to defer this to the
>   	 * real transfer function.
>   	 */
>   	priv->mode = mode;
> -	dev_dbg(bus, "mode=%d\n", priv->mode);
> +	dev_dbg(bus, "mode=%x\n", mode);
>   
>   	return 0;
>   }
> @@ -813,10 +827,13 @@ static const struct udevice_id dw_spi_ids[] = {
>   	 */
>   	{ .compatible = "altr,socfpga-spi" },
>   	{ .compatible = "altr,socfpga-arria10-spi" },
> -	{ .compatible = "canaan,kendryte-k210-spi" },
> +	{
> +		.compatible = "canaan,kendryte-k210-spi",
> +		.data = DW_SPI_CAP_QUAD | DW_SPI_CAP_OCTAL,
> +	},
>   	{
>   		.compatible = "canaan,kendryte-k210-ssi",
> -		.data = DW_SPI_CAP_DWC_SSI,
> +		.data = DW_SPI_CAP_DWC_SSI | DW_SPI_CAP_QUAD,
>   	},
>   	{ .compatible = "intel,stratix10-spi" },
>   	{ .compatible = "intel,agilex-spi" },
>