realtek: RTL931x: disable USXGMII SerDes setup

The first RTL931x devices make their way into OpenWrt. Their copper
ports are driven by different interfaces modes like 10G_QXGMII or
Realtek proprietary XSGMII. The DSA driver has no proper handling
for theses modes implemented yet. So a lot is auto-mapped to USXGMII
internally. As soon as the SerDes setup activates this (wrong) mode
the PHY connectivity breaks.

Disable this mode for now and rely on the proper U-Boot setup.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://github.com/openwrt/openwrt/pull/20292
Signed-off-by: Robert Marko <robimarko@gmail.com>

diff --git a/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c b/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
index d37a372c0613d773ec11cc7bb995957f50ff14d9..508119ff01318b690d8bc663d7796b53568fda5e 100644 (file)
--- a/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
+++ b/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
@@ -692,10 +692,16 @@ static void rtl931x_phylink_mac_config(struct dsa_switch *ds, int port,
                rtl931x_sds_init(sds_num, PHY_INTERFACE_MODE_10GBASER);
                break;
        case PHY_INTERFACE_MODE_USXGMII:
-               /* Translates to MII_USXGMII_10GSXGMII */
-               band = rtl931x_sds_cmu_band_get(sds_num, PHY_INTERFACE_MODE_USXGMII);
-               rtl931x_sds_init(sds_num, PHY_INTERFACE_MODE_USXGMII);
-               break;
+               /*
+                * TODO: USXGMII is currently the swiss army knife to declare 10G
+                * multi port PHYs. Real devices use other modes instead. Especially
+                *
+                * - RTL8224 is driven in 10G_QXGMII
+                * - RTL8218D/E are driven in (Realtek proprietary) XSGMII (10G SGMII)
+                *
+                * For now disable all USXGMII SerDes handling and rely on U-Boot setup.
+                */
+                break;
        case PHY_INTERFACE_MODE_SGMII:
                pr_info("%s setting mode PHY_INTERFACE_MODE_SGMII\n", __func__);
                band = rtl931x_sds_cmu_band_get(sds_num, PHY_INTERFACE_MODE_SGMII);