[PATCH 4/4] ethernet: stmmac: dwmac-rk: Add RK3506 GMAC support

[Jonas Karlman]

Hi Heiko,

On 10/22/2025 12:43 AM, Heiko Stuebner wrote:
> From: David Wu <david.wu at rock-chips.com>
> 
> Add the needed glue blocks for the RK3506-specific setup.
> 
> The RK3506 dwmac only supports up to 100MBit with a RMII PHY,
> but no RGMII.
> 
> Signed-off-by: David Wu <david.wu at rock-chips.com>
> Signed-off-by: Heiko Stuebner <heiko at sntech.de>
> ---
>  .../net/ethernet/stmicro/stmmac/dwmac-rk.c    | 79 +++++++++++++++++++
>  1 file changed, 79 insertions(+)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> index 51ea0caf16c1..e1e036e7163c 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> @@ -827,6 +827,84 @@ static const struct rk_gmac_ops rk3399_ops = {
>  	.set_speed = rk3399_set_speed,
>  };
>  
> +#define RK3506_GRF_SOC_CON8		0X0020
> +#define RK3506_GRF_SOC_CON11		0X002c

Maybe 0x0020 and 0x002c (lower case x) ?

> +
> +#define RK3506_GMAC_RMII_MODE		GRF_BIT(1)
> +
> +#define RK3506_GMAC_CLK_RMII_DIV2	GRF_BIT(3)
> +#define RK3506_GMAC_CLK_RMII_DIV20	GRF_CLR_BIT(3)
> +
> +#define RK3506_GMAC_CLK_SELET_CRU	GRF_CLR_BIT(5)
> +#define RK3506_GMAC_CLK_SELET_IO	GRF_BIT(5)

s/SELET/SELECT/

> +
> +#define RK3506_GMAC_CLK_RMII_GATE	GRF_BIT(2)
> +#define RK3506_GMAC_CLK_RMII_NOGATE	GRF_CLR_BIT(2)
> +
> +static void rk3506_set_to_rmii(struct rk_priv_data *bsp_priv)
> +{
> +	struct device *dev = bsp_priv->dev;
> +	unsigned int id = bsp_priv->id, offset;
> +
> +	if (IS_ERR(bsp_priv->grf)) {
> +		dev_err(dev, "%s: Missing rockchip,grf property\n", __func__);
> +		return;
> +	}

Please drop this, it is already checked in rk_gmac_setup().

> +
> +	offset = (id == 1) ? RK3506_GRF_SOC_CON11 : RK3506_GRF_SOC_CON8;
> +	regmap_write(bsp_priv->grf, offset, RK3506_GMAC_RMII_MODE);
> +}
> +
> +static int rk3506_set_speed(struct rk_priv_data *bsp_priv,
> +			    phy_interface_t interface, int speed)
> +{
> +	struct device *dev = bsp_priv->dev;
> +	unsigned int val, offset, id = bsp_priv->id;
> +
> +	switch (speed) {
> +	case 10:
> +		val = RK3506_GMAC_CLK_RMII_DIV20;
> +		break;
> +	case 100:
> +		val = RK3506_GMAC_CLK_RMII_DIV2;
> +		break;
> +	default:
> +		dev_err(dev, "unknown speed value for RMII! speed=%d", speed);
> +		return -EINVAL;
> +	}
> +
> +	offset = (id == 1) ? RK3506_GRF_SOC_CON11 : RK3506_GRF_SOC_CON8;
> +	regmap_write(bsp_priv->grf, offset, val);
> +
> +	return 0;

This should probably be converted to use rk_reg_speed_data with
something like:

static const struct rk_reg_speed_data rk3506_reg_speed_data = {
	.rmii_10 = RK3506_GMAC_CLK_RMII_DIV20,
	.rmii_100 = RK3506_GMAC_CLK_RMII_DIV2,
};

and:

	return rk_set_reg_speed(bsp_priv, &rk3506_reg_speed_data,
				offset, interface, speed);

> +}
> +
> +static void rk3506_set_clock_selection(struct rk_priv_data *bsp_priv,
> +				       bool input, bool enable)
> +{
> +	unsigned int value, offset, id = bsp_priv->id;
> +
> +	offset = (id == 1) ? RK3506_GRF_SOC_CON11 : RK3506_GRF_SOC_CON8;
> +
> +	value = input ? RK3506_GMAC_CLK_SELET_IO :
> +			RK3506_GMAC_CLK_SELET_CRU;

s/SELET/SELECT/

Regards,
Jonas

> +	value |= enable ? RK3506_GMAC_CLK_RMII_NOGATE :
> +			  RK3506_GMAC_CLK_RMII_GATE;
> +	regmap_write(bsp_priv->grf, offset, value);
> +}
> +
> +static const struct rk_gmac_ops rk3506_ops = {
> +	.set_to_rmii = rk3506_set_to_rmii,
> +	.set_speed = rk3506_set_speed,
> +	.set_clock_selection = rk3506_set_clock_selection,
> +	.regs_valid = true,
> +	.regs = {
> +		0xff4c8000, /* gmac0 */
> +		0xff4d0000, /* gmac1 */
> +		0x0, /* sentinel */
> +	},
> +};
> +
>  #define RK3528_VO_GRF_GMAC_CON		0x0018
>  #define RK3528_VO_GRF_MACPHY_CON0	0x001c
>  #define RK3528_VO_GRF_MACPHY_CON1	0x0020
> @@ -1808,6 +1886,7 @@ static const struct of_device_id rk_gmac_dwmac_match[] = {
>  	{ .compatible = "rockchip,rk3366-gmac", .data = &rk3366_ops },
>  	{ .compatible = "rockchip,rk3368-gmac", .data = &rk3368_ops },
>  	{ .compatible = "rockchip,rk3399-gmac", .data = &rk3399_ops },
> +	{ .compatible = "rockchip,rk3506-gmac", .data = &rk3506_ops },
>  	{ .compatible = "rockchip,rk3528-gmac", .data = &rk3528_ops },
>  	{ .compatible = "rockchip,rk3568-gmac", .data = &rk3568_ops },
>  	{ .compatible = "rockchip,rk3576-gmac", .data = &rk3576_ops },