[PATCH net-next] net: dsa: microchip: enable SGMII port for KSZ9897
From: Tapio Reijonen <hidden>
Date: 2026-07-03 06:37:40
Also in:
lkml
Subsystem:
microchip ksz series ethernet switch driver, networking drivers, networking [dsa], the rest · Maintainers:
Woojung Huh, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Vladimir Oltean, Linus Torvalds
The KSZ9897 has an SGMII/1000BASE-X capable port 7, but its chip_info entry never set .sgmii_port. As a result ksz_has_sgmii_port() is false, ksz9477_pcs_create() is never called, and ksz9477_phylink_mac_select_pcs() returns NULL for port 7, so no PCS is ever instantiated and a phy-mode = "sgmii" or "1000base-x" link on that port cannot come up. The KSZ9897 shares the KSZ9477 register layout and operations (ksz9477_dev_ops, ksz9477_regs) and reaches its port-7 PCS through the same SPI-indirect XPCS register window. The register-identical LAN9646 already enables this via .sgmii_port = 7. Set the same for the KSZ9897 so the XPCS instance is created and 1000BASE-X / SGMII links on port 7 negotiate correctly. Tested on a KSZ9897 with a 1000BASE-X fibre SFP wired directly to port 7: the link negotiates at 1Gbps/full duplex and passes traffic. Signed-off-by: Tapio Reijonen <redacted> --- drivers/net/dsa/microchip/ksz_common.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index d1726778bb488e424aed450fb02c8fe4b332a1f4..718c72206ab451cb4c5e88fc91a5eae4892518b7 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c@@ -1591,6 +1591,7 @@ const struct ksz_chip_data ksz_switch_chips[] = { .internal_phy = {true, true, true, true, true, false, false}, .gbit_capable = {true, true, true, true, true, true, true}, + .sgmii_port = 7, }, [KSZ9893] = {
--- base-commit: 322008f87f917e2217eeac386a9410945092eb2e change-id: 20260703-ksz9897-sgmii-port-48ddb100e015 Best regards, -- Tapio Reijonen [off-list ref]