[PATCH net-next v5 4/9] net: pcs: xpcs: re-initiate clause 37 Auto-negotiation
From: Choong Yong Liang
Date: Wed Feb 14 2024 - 22:09:16 EST
According to the XPCS datasheet, a soft reset is required to initiate
Clause 37 auto-negotiation when the XPCS switches interface modes.
When the interface mode is set to 2500BASE-X, Clause 37 Auto-Negotiation
is turned off.
Subsequently, when the interface mode switches from 2500BASE-X to SGMII,
re-initiating Clause 37 auto-negotiation is required for the SGMII
interface mode to function properly.
Signed-off-by: Choong Yong Liang <yong.liang.choong@xxxxxxxxxxxxxxx>
---
drivers/net/pcs/pcs-xpcs.c | 62 +++++++++++++++++++++++++++++++++++---
1 file changed, 57 insertions(+), 5 deletions(-)
diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c
index 52a7757ee419..cf1ed89d6418 100644
--- a/drivers/net/pcs/pcs-xpcs.c
+++ b/drivers/net/pcs/pcs-xpcs.c
@@ -848,6 +848,60 @@ static int xpcs_config_2500basex(struct dw_xpcs *xpcs)
return xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_CTRL, ret);
}
+static int xpcs_switch_to_aneg_c37_sgmii(const struct xpcs_compat *compat,
+ struct dw_xpcs *xpcs,
+ unsigned int neg_mode)
+{
+ bool an_c37_enabled;
+ int ret, mdio_ctrl;
+
+ if (neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED) {
+ mdio_ctrl = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_CTRL);
+ if (mdio_ctrl < 0)
+ return mdio_ctrl;
+
+ an_c37_enabled = mdio_ctrl & AN_CL37_EN;
+ if (!an_c37_enabled) {
+ //Perform soft reset to initiate C37 auto-negotiation
+ ret = xpcs_soft_reset(xpcs, compat);
+ if (ret)
+ return ret;
+ }
+ }
+ return 0;
+}
+
+static int xpcs_switch_interface_mode(const struct xpcs_compat *compat,
+ struct dw_xpcs *xpcs,
+ phy_interface_t interface,
+ unsigned int neg_mode)
+{
+ int ret;
+
+ if (xpcs->dev_flag == DW_DEV_TXGBE) {
+ ret = txgbe_xpcs_switch_mode(xpcs, interface);
+ if (ret)
+ return ret;
+ } else {
+ if (xpcs->interface != interface) {
+ xpcs->interface = interface;
+
+ switch (compat->an_mode) {
+ case DW_AN_C37_SGMII:
+ ret = xpcs_switch_to_aneg_c37_sgmii(compat,
+ xpcs,
+ neg_mode);
+ if (ret)
+ return ret;
+ break;
+ default:
+ return 0;
+ }
+ }
+ }
+ return 0;
+}
+
int xpcs_do_config(struct dw_xpcs *xpcs, phy_interface_t interface,
const unsigned long *advertising, unsigned int neg_mode)
{
@@ -858,11 +912,9 @@ int xpcs_do_config(struct dw_xpcs *xpcs, phy_interface_t interface,
if (!compat)
return -ENODEV;
- if (xpcs->dev_flag == DW_DEV_TXGBE) {
- ret = txgbe_xpcs_switch_mode(xpcs, interface);
- if (ret)
- return ret;
- }
+ ret = xpcs_switch_interface_mode(compat, xpcs, interface, neg_mode);
+ if (ret)
+ return ret;
switch (compat->an_mode) {
case DW_10GBASER:
--
2.34.1