From 456a389f594a1a46a2913cf082579a9ceec481eb Mon Sep 17 00:00:00 2001 From: Nathan Whitehorn Date: Tue, 22 Sep 2026 11:09:24 -0400 Subject: [PATCH 1/2] net: macb: Poll for link state changes when using the internal PCS. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When used with an offboard transceiver (e.g. an SFP), link state needs to be measured at the PCS rather than an onboard PHY. Poll the link state when the PCS is active to allow the kernel to detect link state changes in this case. Signed-off-by: Nathan Whitehorn Reviewed-by: Théo Lebrun Link: https://patch.msgid.link/20260922151429.23272-2-nwhitehorn@pa.msu.edu Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index e3ee7d1d1263..1b8f6a752b05 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -1025,6 +1025,7 @@ static int macb_mii_probe(struct net_device *netdev) struct macb *bp = netdev_priv(netdev); bp->phylink_sgmii_pcs.ops = &macb_phylink_pcs_ops; + bp->phylink_sgmii_pcs.poll = true; bp->phylink_usx_pcs.ops = &macb_phylink_usx_pcs_ops; bp->phylink_config.dev = &netdev->dev; From f342b1208f8df6c6b4c45d0702e6f150357d0143 Mon Sep 17 00:00:00 2001 From: Nathan Whitehorn Date: Tue, 22 Sep 2026 11:09:25 -0400 Subject: [PATCH 2/2] net: macb: add support for 1000BASE-X autonegotiation to PCS The current PCS code unconditionally uses SGMII autonegotiation, though the hardware supports both SGMII and 1000BASE-X modes. Decouple the choice of PCS enablement from use of the SGMII mode when running at gigabit rates and announce to phylink that 1000BASE-X is a supported operating mode. This enables direct attachment of the PCS to e.g. an SFP. The 1000BASE-X code in phylink also sometimes calls the autonegotiation restart method, so add an implementation of autonegotiation restart and make sure that pcs_config() signals to phylink when the AN advertisement has changed. Signed-off-by: Nathan Whitehorn Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/20260922151429.23272-3-nwhitehorn@pa.msu.edu Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 36 ++++++++++++++++++------ 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 1b8f6a752b05..c26ffcf73562 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -583,7 +583,12 @@ static void macb_pcs_get_state(struct phylink_pcs *pcs, unsigned int neg_mode, static void macb_pcs_an_restart(struct phylink_pcs *pcs) { - /* Not supported */ + struct macb *bp = container_of(pcs, struct macb, phylink_sgmii_pcs); + u32 old, new; + + old = gem_readl(bp, PCSCNTRL); + new = old | BMCR_ANRESTART; + gem_writel(bp, PCSCNTRL, new); } static int macb_pcs_config(struct phylink_pcs *pcs, @@ -594,11 +599,17 @@ static int macb_pcs_config(struct phylink_pcs *pcs, { struct macb *bp = container_of(pcs, struct macb, phylink_sgmii_pcs); u32 old, new; + int ret = 0; old = gem_readl(bp, PCSANADV); new = phylink_mii_c22_pcs_encode_advertisement(interface, advertising); - if (new != -EINVAL && old != new) + if (new != -EINVAL && old != new) { + /* pcs_config() is supposed to return 1 if AN advertisement + * has changed + */ + ret = 1; gem_writel(bp, PCSANADV, new); + } /* Disable AN if it's not to be used, enable otherwise. * Must be written after PCSSEL is set in NCFGR which is done in @@ -612,7 +623,7 @@ static int macb_pcs_config(struct phylink_pcs *pcs, if (old != new) gem_writel(bp, PCSCNTRL, new); - return 0; + return ret; } static const struct phylink_pcs_ops macb_phylink_usx_pcs_ops = { @@ -750,7 +761,9 @@ static void macb_mac_config(struct phylink_config *config, unsigned int mode, ctrl &= ~(GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL)); ncr &= ~GEM_BIT(ENABLE_HS_MAC); - if (state->interface == PHY_INTERFACE_MODE_SGMII) { + if (state->interface == PHY_INTERFACE_MODE_1000BASEX) { + ctrl |= GEM_BIT(PCSSEL); + } else if (state->interface == PHY_INTERFACE_MODE_SGMII) { ctrl |= GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL); } else if (state->interface == PHY_INTERFACE_MODE_10GBASER) { ctrl |= GEM_BIT(PCSSEL); @@ -957,7 +970,8 @@ static struct phylink_pcs *macb_mac_select_pcs(struct phylink_config *config, if (interface == PHY_INTERFACE_MODE_10GBASER) return &bp->phylink_usx_pcs; - else if (interface == PHY_INTERFACE_MODE_SGMII) + else if (interface == PHY_INTERFACE_MODE_1000BASEX || + interface == PHY_INTERFACE_MODE_SGMII) return &bp->phylink_sgmii_pcs; else return NULL; @@ -1032,7 +1046,8 @@ static int macb_mii_probe(struct net_device *netdev) bp->phylink_config.type = PHYLINK_NETDEV; bp->phylink_config.mac_managed_pm = true; - if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) { + if (bp->phy_interface == PHY_INTERFACE_MODE_1000BASEX || + bp->phy_interface == PHY_INTERFACE_MODE_SGMII) { bp->phylink_config.poll_fixed_state = true; bp->phylink_config.get_fixed_state = macb_get_pcs_fixed_state; /* The PCSAUTONEG bit in PCSCNTRL is on out of reset. Setting @@ -1061,9 +1076,12 @@ static int macb_mii_probe(struct net_device *netdev) bp->phylink_config.supported_interfaces); phy_interface_set_rgmii(bp->phylink_config.supported_interfaces); - if (bp->caps & MACB_CAPS_PCS) + if (bp->caps & MACB_CAPS_PCS) { + __set_bit(PHY_INTERFACE_MODE_1000BASEX, + bp->phylink_config.supported_interfaces); __set_bit(PHY_INTERFACE_MODE_SGMII, bp->phylink_config.supported_interfaces); + } if (bp->caps & MACB_CAPS_HIGH_SPEED) { __set_bit(PHY_INTERFACE_MODE_10GBASER, @@ -4921,7 +4939,9 @@ static int macb_init_dflt(struct platform_device *pdev) /* Set MII management clock divider */ val = macb_mdc_clk_div(bp); val |= macb_dbw(bp); - if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) + if (bp->phy_interface == PHY_INTERFACE_MODE_1000BASEX) + val |= GEM_BIT(PCSSEL); + else if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) val |= GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL); macb_writel(bp, NCFGR, val);