generic: net: phy: be more conservative about MAC interface selection

Only add SerDes interface modes at lower speeds to host_interfaces.

Fixes: 5281033831 ("generic: net: phy: use all SerDes MAC interface modes")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>

diff --git a/target/linux/generic/pending-6.6/706-net-phy-populate-host_interfaces-when-attaching-PHY.patch b/target/linux/generic/pending-6.6/706-net-phy-populate-host_interfaces-when-attaching-PHY.patch
index bd2d015b179d1e91835d2ca146c37eaf6a28e436..78e0049f05243fe7512301ca4a134184ef5d4e96 100644 (file)
--- a/target/linux/generic/pending-6.6/706-net-phy-populate-host_interfaces-when-attaching-PHY.patch
+++ b/target/linux/generic/pending-6.6/706-net-phy-populate-host_interfaces-when-attaching-PHY.patch
@@ -1,4 +1,4 @@
-From 9e1a0d2006bc108b239b5bc00b42c2a8cc651217 Mon Sep 17 00:00:00 2001
+From 4e432e530db0056450fbc4a3cee793f16adc39a7 Mon Sep 17 00:00:00 2001
 From: Daniel Golle <daniel@makrotopia.org>
 Date: Tue, 8 Oct 2024 23:58:41 +0100
 Subject: [PATCH] net: phy: populate host_interfaces when attaching PHY
@@ -15,18 +15,39 @@ full-duplex only.
 
 Signed-off-by: Daniel Golle <daniel@makrotopia.org>
 ---
- drivers/net/phy/phylink.c | 7 +++++++
- 1 file changed, 7 insertions(+)
+ drivers/net/phy/phylink.c | 21 ++++++++++++++++++++-
+ 1 file changed, 20 insertions(+), 1 deletion(-)
 
 --- a/drivers/net/phy/phylink.c
 +++ b/drivers/net/phy/phylink.c
-@@ -2044,6 +2044,13 @@ int phylink_fwnode_phy_connect(struct ph
+@@ -2017,7 +2017,7 @@ int phylink_fwnode_phy_connect(struct ph
+ {
+       struct fwnode_handle *phy_fwnode;
+       struct phy_device *phy_dev;
+-      int ret;
++      int i, ret;
+ 
+       /* Fixed links and 802.3z are handled without needing a PHY */
+       if (pl->cfg_link_an_mode == MLO_AN_FIXED ||
+@@ -2044,6 +2044,25 @@ int phylink_fwnode_phy_connect(struct ph
                pl->link_config.interface = pl->link_interface;
        }
  
-+      /* Assume SerDes interface modes share the same lanes and allow
-+       * the PHY to switch between them
++      /* Assume single-lane SerDes interface modes share the same
++       * lanes and allow the PHY to switch to slower also supported modes
 +       */
++      for (i = ARRAY_SIZE(phylink_sfp_interface_preference) - 1; i >= 0; i--) {
++              /* skip unsupported modes */
++              if (!test_bit(phylink_sfp_interface_preference[i], pl->config->supported_interfaces))
++                      continue;
++
++              __set_bit(phylink_sfp_interface_preference[i], phy_dev->host_interfaces);
++
++              /* skip all faster modes */
++              if (phylink_sfp_interface_preference[i] == pl->link_interface)
++                      break;
++      }
++
 +      if (test_bit(pl->link_interface, phylink_sfp_interfaces))
 +              phy_interface_and(phy_dev->host_interfaces, phylink_sfp_interfaces,
 +                                pl->config->supported_interfaces);