Subject: Re: [PATCH v2] net: phy: marvell: Add errata section 5.1 for Alaska PHY

From: Marek Behún <[email-masked]>
Date: Mon, 16 May 2022 11:25:55 +0200

On Mon, 16 May 2022 09:08:59 +0200
Stefan Roese <[email-masked]> wrote:

> From: Leszek Polak <[email-masked]>
> 
> As per Errata Section 5.1, if EEE is intended to be used, some register
> writes must be done once after every hardware reset. This patch now adds
> the necessary register writes as listed in the Marvell errata.
> 
> Without this fix we experience ethernet problems on some of our boards
> equipped with a new version of this ethernet PHY (different supplier).
> 
> The fix applies to Marvell Alaska 88E1510/88E1518/88E1512/88E1514
> Rev. A0.
> 
> Signed-off-by: Leszek Polak <[email-masked]>
> Signed-off-by: Stefan Roese <[email-masked]>
> Cc: Marek Behún <[email-masked]>
> Cc: Andrew Lunn <[email-masked]>
> Cc: Heiner Kallweit <[email-masked]>
> Cc: Russell King <[email-masked]>
> Cc: David S. Miller <[email-masked]>
> ---
> v2:
> - Implement struct with errata reg values and loop over this
>   struct instead of using single phy_write() call for each PHY
>   reg value, as suggested by Marek
> 
>  drivers/net/phy/marvell.c | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 
> diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
> index 2702faf7b0f6..41353f615a66 100644
> --- a/drivers/net/phy/marvell.c
> +++ b/drivers/net/phy/marvell.c
> @@ -1177,7 +1177,44 @@ static int m88e1318_config_init(struct phy_device *phydev)
>  
>  static int m88e1510_config_init(struct phy_device *phydev)
>  {
> +	static const struct {
> +		u16 reg17, reg16;
> +	} errata_vals[] = {
> +		{ 0x214b, 0x2144 },
> +		{ 0x0c28, 0x2146 },
> +		{ 0xb233, 0x214d },
> +		{ 0xcc0c, 0x2159 },
> +	};
>  	int err;
> +	int i;
> +
> +	/* As per Marvell Release Notes - Alaska 88E1510/88E1518/88E1512/
> +	 * 88E1514 Rev A0, Errata Section 5.1:
> +	 * If EEE is intended to be used, the following register writes
> +	 * must be done once after every hardware reset.
> +	 */
> +	err = marvell_set_page(phydev, 0x00FF);
> +	if (err < 0)
> +		return err;
> +
> +	for (i = 0; i < ARRAY_SIZE(errata_vals); ++i) {
> +		err = phy_write(phydev, 17, errata_vals[i].reg17);
> +		if (err)
> +			return err;
> +		err = phy_write(phydev, 16, errata_vals[i].reg16);
> +		if (err)
> +			return err;
> +	}
> +
> +	err = marvell_set_page(phydev, 0x00FB);
> +	if (err < 0)
> +		return err;
> +	err = phy_write(phydev, 07, 0xC00D);
> +	if (err < 0)
> +		return err;
> +	err = marvell_set_page(phydev, MII_MARVELL_COPPER_PAGE);
> +	if (err < 0)
> +		return err;
>  
>  	/* SGMII-to-Copper mode initialization */
>  	if (phydev->interface == PHY_INTERFACE_MODE_SGMII) {

Reviewed-by: Marek Behún <[email-masked]>