[net-next,21/21] net: stmmac: rk: rk3506, rk3528 and kk3588 have rmii_mode in clock register

[Jakub Kicinski]

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---
net: stmmac: rk: rk3506, rk3528 and kk3588 have rmii_mode in clock register

This commit moves the RMII mode bit configuration from the dedicated
set_to_rmii() functions to rk_gmac_powerup() using a new rmii_mode_mask
field in the clock register structure.

> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> index ebbc09ea572a..759deb66ef2a 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c

[ ... ]

> @@ -1412,6 +1385,15 @@ static int rk_gmac_powerup(struct rk_priv_data *bsp_priv)
>  			return ret;
>  	}

For context, prior to this hunk, ret is set by rk_get_phy_intf_sel() to
hold the PHY interface value (e.g., PHY_INTF_SEL_RMII = 4). Then in the
block above (not shown here), if gmac_phy_intf_sel_mask is set, there is:

    ret = regmap_write(bsp_priv->grf, bsp_priv->gmac_grf_reg, val);

This overwrites ret with the regmap_write() return value (0 on success).

> +	if (bsp_priv->clock.rmii_mode_mask) {
> +		val = rk_encode_wm16(ret == PHY_INTF_SEL_RMII,
> +				     bsp_priv->clock.rmii_mode_mask);

For rk3588, gmac_phy_intf_sel_mask is set in rk3588_init(), so the
previous block executes and ret becomes 0. Then here, the comparison
ret == PHY_INTF_SEL_RMII evaluates to 0 == 4, which is always false.

This means the RMII mode bit will never be set for rk3588 in RMII mode.
Should this use bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII instead,
or should the PHY interface value be saved to a separate variable before
it gets overwritten?

> +
> +		ret = rk_write_clock_grf_reg(bsp_priv, val);
> +		if (ret < 0)
> +			return ret;
> +	}

[ ... ]