Re: [PATCH net-next 1/2] net: phy: at803x: add fiber support

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Wed, Jun 30, 2021 at 12:01:45PM -0600, Robert Hancock wrote:
> Previously this driver always forced the copper page to be selected,
> however for AR8031 in 100Base-FX or 1000Base-X modes, the fiber page
> needs to be selected. Set the appropriate mode based on the hardware
> mode_cfg strap selection.
> 
> Enable the appropriate interrupt bits to detect fiber-side link up
> or down events.
> 
> Update config_aneg and read_status methods to use the appropriate
> Clause 37 calls when fiber mode is in use.
> 
> Signed-off-by: Robert Hancock <robert.hancock@calian.com>
> ---
>  drivers/net/phy/at803x.c | 69 ++++++++++++++++++++++++++++++++++------
>  1 file changed, 59 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
> index 5d62b85a4024..65f546eca5f4 100644
> --- a/drivers/net/phy/at803x.c
> +++ b/drivers/net/phy/at803x.c
> @@ -48,6 +48,8 @@
>  #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
>  #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
>  #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
> +#define AT803X_INTR_ENABLE_LINK_FAIL_BX		BIT(8)
> +#define AT803X_INTR_ENABLE_LINK_SUCCESS_BX	BIT(7)
>  #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
>  #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
>  #define AT803X_INTR_ENABLE_WOL			BIT(0)
> @@ -81,7 +83,17 @@
>  #define AT803X_DEBUG_DATA			0x1E
>  
>  #define AT803X_MODE_CFG_MASK			0x0F
> -#define AT803X_MODE_CFG_SGMII			0x01
> +#define AT803X_MODE_CFG_BASET_RGMII		0x00
> +#define AT803X_MODE_CFG_BASET_SGMII		0x01
> +#define AT803X_MODE_CFG_BX1000_RGMII_50		0x02
> +#define AT803X_MODE_CFG_BX1000_RGMII_75		0x03
> +#define AT803X_MODE_CFG_BX1000_CONV_50		0x04
> +#define AT803X_MODE_CFG_BX1000_CONV_75		0x05
> +#define AT803X_MODE_CFG_FX100_RGMII_50		0x06
> +#define AT803X_MODE_CFG_FX100_CONV_50		0x07
> +#define AT803X_MODE_CFG_RGMII_AUTO_MDET		0x0B
> +#define AT803X_MODE_CFG_FX100_RGMII_75		0x0E
> +#define AT803X_MODE_CFG_FX100_CONV_75		0x0F
>  
>  #define AT803X_PSSR				0x11	/*PHY-Specific Status Register*/
>  #define AT803X_PSSR_MR_AN_COMPLETE		0x0200
> @@ -191,6 +203,8 @@ struct at803x_priv {
>  	u16 clk_25m_mask;
>  	u8 smarteee_lpi_tw_1g;
>  	u8 smarteee_lpi_tw_100m;
> +	bool is_fiber;
> +	bool is_1000basex;
>  	struct regulator_dev *vddio_rdev;
>  	struct regulator_dev *vddh_rdev;
>  	struct regulator *vddio;
> @@ -673,12 +687,32 @@ static int at803x_probe(struct phy_device *phydev)
>  	}
>  
>  	/* Some bootloaders leave the fiber page selected.
> -	 * Switch to the copper page, as otherwise we read
> -	 * the PHY capabilities from the fiber side.
> +	 * Switch to the appropriate page (fiber or copper), as otherwise we
> +	 * read the PHY capabilities from the wrong page.
>  	 */
>  	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
> +		int mode_cfg;
> +
> +		ret = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
> +		if (ret < 0)
> +			goto err;
> +		mode_cfg = ret & AT803X_MODE_CFG_MASK;
> +
> +		switch (mode_cfg) {
> +		case AT803X_MODE_CFG_BX1000_RGMII_50:
> +		case AT803X_MODE_CFG_BX1000_RGMII_75:
> +			priv->is_1000basex = true;
> +			fallthrough;
> +		case AT803X_MODE_CFG_FX100_RGMII_50:
> +		case AT803X_MODE_CFG_FX100_RGMII_75:
> +			priv->is_fiber = true;
> +			break;
> +		}
> +
>  		phy_lock_mdio_bus(phydev);
> -		ret = at803x_write_page(phydev, AT803X_PAGE_COPPER);
> +		ret = at803x_write_page(phydev,
> +					priv->is_fiber ? AT803X_PAGE_FIBER :
> +							 AT803X_PAGE_COPPER);
>  		phy_unlock_mdio_bus(phydev);

Does this configuration have to be restored when the PHY is resumed,
or can we assume that this is always retained? Should this be moved
to the config_init method?

-- 
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