On Tue, 8 Jun 2021 11:15:34 +0800
Joakim Zhang <qiangqing.zhang@xxxxxxx> wrote:
>
>
> If enable Advance Link Down Power Saving (ALDPS) mode, it will change
> crystal/clock behavior, which cause RXC clock stop for dozens to hundreds
> of miliseconds. This is comfirmed by Realtek engineer. For some MACs, it
> needs RXC clock to support RX logic, after this patch, PHY can generate
> continuous RXC clock during auto-negotiation.
>
> ALDPS default is disabled after hardware reset, it's more reasonable to
> add a property to enable this feature, since ALDPS would introduce side effect.
> This patch adds dt property "realtek,aldps-enable" to enable ALDPS mode
> per users' requirement.
>
> Jisheng Zhang enables this feature, changes the default behavior. Since
> mine patch breaks the rule that new implementation should not break
> existing design, so Cc'ed let him know to see if it can be accepted.
>
> Cc: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
> Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> ---
> drivers/net/phy/realtek.c | 20 +++++++++++++++++---
> 1 file changed, 17 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
> index ca258f2a9613..79dc55bb4091 100644
> --- a/drivers/net/phy/realtek.c
> +++ b/drivers/net/phy/realtek.c
> @@ -76,6 +76,7 @@ MODULE_AUTHOR("Johnson Leung");
> MODULE_LICENSE("GPL");
>
> struct rtl821x_priv {
> + u16 phycr1;
> u16 phycr2;
> };
>
> @@ -98,6 +99,14 @@ static int rtl821x_probe(struct phy_device *phydev)
> if (!priv)
> return -ENOMEM;
>
> + priv->phycr1 = phy_read_paged(phydev, 0xa43, RTL8211F_PHYCR1);
> + if (priv->phycr1 < 0)
> + return priv->phycr1;
> +
> + priv->phycr1 &= (RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_XTAL_OFF);
priv->phycr1 is 0 by default, so above 5 LoCs can be removed
> + if (of_property_read_bool(dev->of_node, "realtek,aldps-enable"))
> + priv->phycr1 |= RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_XTAL_OFF;
> +
> priv->phycr2 = phy_read_paged(phydev, 0xa43, RTL8211F_PHYCR2);
> if (priv->phycr2 < 0)
> return priv->phycr2;
> @@ -324,11 +333,16 @@ static int rtl8211f_config_init(struct phy_device *phydev)
> struct rtl821x_priv *priv = phydev->priv;
> struct device *dev = &phydev->mdio.dev;
> u16 val_txdly, val_rxdly;
> - u16 val;
> int ret;
>
> - val = RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_XTAL_OFF;
> - phy_modify_paged_changed(phydev, 0xa43, RTL8211F_PHYCR1, val, val);
> + ret = phy_modify_paged_changed(phydev, 0xa43, RTL8211F_PHYCR1,
> + RTL8211F_ALDPS_PLL_OFF | RTL8211F_ALDPS_ENABLE | RTL8211F_ALDPS_XTAL_OFF,
> + priv->phycr1);
> + if (ret < 0) {
> + dev_err(dev, "aldps mode configuration failed: %pe\n",
> + ERR_PTR(ret));
> + return ret;
> + }
>
> switch (phydev->interface) {
> case PHY_INTERFACE_MODE_RGMII:
> --
> 2.17.1
>
