[PATCH 1/8] net: phy: realtek: rtl8221: allow to configure SERDES mode

Daniel Golle
2023-05-10T22:58:38Z

From: Alexander Couzens <lynxis@fe80.eu>

The rtl8221 supports multiple SERDES modes:
- SGMII
- 2500base-x
- HiSGMII

Further it supports rate adaption on SERDES links to allow
slow ethernet speeds (10/100/1000mbit) to work on 2500base-x/HiSGMII
links without reducing the SERDES speed.

When operating without rate adapters the SERDES link will follow the
ethernet speed.

Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
---
drivers/net/phy/realtek.c | 55 +++++++++++++++++++++++++++++++++++++++
1 file changed, 55 insertions(+)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index 3d99fd6664d7..a7dd5a075135 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -53,6 +53,15 @@
RTL8201F_ISR_LINK)
#define RTL8201F_IER 0x13

+#define RTL8221B_MMD_SERDES_CTRL MDIO_MMD_VEND1
+#define RTL8221B_MMD_PHY_CTRL MDIO_MMD_VEND2
+#define RTL8221B_SERDES_OPTION 0x697a
+#define RTL8221B_SERDES_OPTION_MODE_MASK GENMASK(5, 0)
+#define RTL8221B_SERDES_OPTION_MODE_2500BASEX_SGMII 0
+#define RTL8221B_SERDES_OPTION_MODE_HISGMII_SGMII 1
+#define RTL8221B_SERDES_OPTION_MODE_2500BASEX 2
+#define RTL8221B_SERDES_OPTION_MODE_HISGMII 3
+
#define RTL8366RB_POWER_SAVE 0x15
#define RTL8366RB_POWER_SAVE_ON BIT(12)

@@ -849,6 +858,48 @@ static irqreturn_t rtl9000a_handle_interrupt(struct phy_device *phydev)
return IRQ_HANDLED;
}

+static int rtl8221b_config_init(struct phy_device *phydev)
+{
+ u16 option_mode;
+
+ switch (phydev->interface) {
+ case PHY_INTERFACE_MODE_2500BASEX:
+ if (!phydev->is_c45) {
+ option_mode = RTL8221B_SERDES_OPTION_MODE_2500BASEX;
+ break;
+ }
+ fallthrough;
+ case PHY_INTERFACE_MODE_SGMII:
+ option_mode = RTL8221B_SERDES_OPTION_MODE_2500BASEX_SGMII;
+ break;
+ default:
+ return 0;
+ }
+
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL,
+ 0x75f3, 0);
+
+ phy_modify_mmd_changed(phydev, RTL8221B_MMD_SERDES_CTRL,
+ RTL8221B_SERDES_OPTION,
+ RTL8221B_SERDES_OPTION_MODE_MASK, option_mode);
+ switch (option_mode) {
+ case RTL8221B_SERDES_OPTION_MODE_2500BASEX_SGMII:
+ case RTL8221B_SERDES_OPTION_MODE_2500BASEX:
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6a04, 0x0503);
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6f10, 0xd455);
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6f11, 0x8020);
+ break;
+ case RTL8221B_SERDES_OPTION_MODE_HISGMII_SGMII:
+ case RTL8221B_SERDES_OPTION_MODE_HISGMII:
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6a04, 0x0503);
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6f10, 0xd433);
+ phy_write_mmd(phydev, RTL8221B_MMD_SERDES_CTRL, 0x6f11, 0x8020);
+ break;
+ }
+
+ return 0;
+}
+
static struct phy_driver realtek_drvs[] = {
{
PHY_ID_MATCH_EXACT(0x00008201),
@@ -970,6 +1021,7 @@ static struct phy_driver realtek_drvs[] = {
.name = "RTL8226B_RTL8221B 2.5Gbps PHY",
.get_features = rtl822x_get_features,
.config_aneg = rtl822x_config_aneg,
+ .config_init = rtl8221b_config_init,
.read_status = rtl822x_read_status,
.suspend = genphy_suspend,
.resume = rtlgen_resume,
@@ -992,6 +1044,7 @@ static struct phy_driver realtek_drvs[] = {
.name = "RTL8226B-CG_RTL8221B-CG 2.5Gbps PHY",
.get_features = rtl822x_get_features,
.config_aneg = rtl822x_config_aneg,
+ .config_init = rtl8221b_config_init,
.read_status = rtl822x_read_status,
.suspend = genphy_suspend,
.resume = rtlgen_resume,
@@ -1002,6 +1055,7 @@ static struct phy_driver realtek_drvs[] = {
.name = "RTL8221B-VB-CG 2.5Gbps PHY",
.get_features = rtl822x_get_features,
.config_aneg = rtl822x_config_aneg,
+ .config_init = rtl8221b_config_init,
.read_status = rtl822x_read_status,
.suspend = genphy_suspend,
.resume = rtlgen_resume,
@@ -1012,6 +1066,7 @@ static struct phy_driver realtek_drvs[] = {
.name = "RTL8221B-VM-CG 2.5Gbps PHY",
.get_features = rtl822x_get_features,
.config_aneg = rtl822x_config_aneg,
+ .config_init = rtl8221b_config_init,
.read_status = rtl822x_read_status,
.suspend = genphy_suspend,
.resume = rtlgen_resume,
--
2.40.0