diff mbox series

[net-next,v3,12/14] net: phylink: make Broadcom BCM84881 based SFPs work

Message ID E1iezfm-0002yu-SG@rmk-PC.armlinux.org.uk
State Accepted
Delegated to: David Miller
Headers show
Series Add support for SFP+ copper modules | expand

Commit Message

Russell King (Oracle) Dec. 11, 2019, 10:56 a.m. UTC 
The Broadcom BCM84881 does not appear to send the SGMII control word
when operating in SGMII mode, which causes network adapters to fail
to link with the PHY, or decide to operate at fixed 1G speed, even if
the PHY negotiated 100M.

Work around this by detecting the Broadcom BCM84881 and switch to phy
mode rather than inband mode.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 6e166449736a..e49232266c79 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1840,10 +1840,20 @@  static void phylink_sfp_link_up(void *upstream)
 	phylink_run_resolve(pl);
 }
 
+/* The Broadcom BCM84881 in the Methode DM7052 is unable to provide a SGMII
+ * or 802.3z control word, so inband will not work.
+ */
+static bool phylink_phy_no_inband(struct phy_device *phy)
+{
+	return phy->is_c45 &&
+		(phy->c45_ids.device_ids[1] & 0xfffffff0) == 0xae025150;
+}
+
 static int phylink_sfp_connect_phy(void *upstream, struct phy_device *phy)
 {
 	struct phylink *pl = upstream;
 	phy_interface_t interface;
+	u8 mode;
 	int ret;
 
 	/*
@@ -1855,9 +1865,13 @@  static int phylink_sfp_connect_phy(void *upstream, struct phy_device *phy)
 	 */
 	phy_support_asym_pause(phy);
 
+	if (phylink_phy_no_inband(phy))
+		mode = MLO_AN_PHY;
+	else
+		mode = MLO_AN_INBAND;
+
 	/* Do the initial configuration */
-	ret = phylink_sfp_config(pl, MLO_AN_INBAND, phy->supported,
-				 phy->advertising);
+	ret = phylink_sfp_config(pl, mode, phy->supported, phy->advertising);
 	if (ret < 0)
 		return ret;