[openwrt/openwrt] realtek: pcs: rtl93xx: handle XSGMII autoneg

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/0d2d9ecb7fac92c9afffeefbb8e673622eb83d38

commit 0d2d9ecb7fac92c9afffeefbb8e673622eb83d38
Author: Jonas Jelonek <jelonek.jonas at gmail.com>
AuthorDate: Mon Jan 26 23:20:26 2026 +0000

    realtek: pcs: rtl93xx: handle XSGMII autoneg
    
    The XSGMII mode is special in several regards. The inband
    autonegotiation for this mode is called 'XSG N-way'. It is controlled
    using different bits and location, and using XSG operations.
    
    Add support for this by enhancing the set_autoneg implementation shared
    by RTL930x and RTL931x. This can stay shared since it works the same for
    both variants.
    
    Signed-off-by: Jonas Jelonek <jelonek.jonas at gmail.com>
    Link: https://github.com/openwrt/openwrt/pull/21762
    Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
---
 .../linux/realtek/files-6.12/drivers/net/pcs/pcs-rtl-otto.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/target/linux/realtek/files-6.12/drivers/net/pcs/pcs-rtl-otto.c b/target/linux/realtek/files-6.12/drivers/net/pcs/pcs-rtl-otto.c
index 234e324c3e..a9c84b4687 100644
--- a/target/linux/realtek/files-6.12/drivers/net/pcs/pcs-rtl-otto.c
+++ b/target/linux/realtek/files-6.12/drivers/net/pcs/pcs-rtl-otto.c
@@ -948,9 +948,18 @@ static int rtpcs_839x_setup_serdes(struct rtpcs_serdes *sds,
 
 static int rtpcs_93xx_sds_set_autoneg(struct rtpcs_serdes *sds, unsigned int neg_mode)
 {
-	u16 bmcr = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED ? BMCR_ANENABLE : 0;
+	u16 bmcr, en_val;
 
-	return rtpcs_sds_modify(sds, 2, MII_BMCR, BMCR_ANENABLE, bmcr);
+	switch (sds->hw_mode) {
+	case RTPCS_SDS_MODE_XSGMII: /* XSG N-way state */
+		en_val = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED ? 0x0 : 0x1;
+
+		return rtpcs_sds_xsg_write_bits(sds, 0x0, 0x2, 9, 8, en_val);
+	default:
+		bmcr = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED ? BMCR_ANENABLE : 0;
+
+		return rtpcs_sds_modify(sds, 0x2, MII_BMCR, BMCR_ANENABLE, bmcr);
+	}
 }
 
 /* RTL930X */