Merge branch 'net-phylink-support-autoneg-configuration-for-sfps'

Russell King says:

====================
net: phylink: support !autoneg configuration for SFPs

This series comes from discussion during a patch series that was posted
at the beginning of April, but these patches were never posted (I was
too busy!)

We restrict ->sfp_interfaces to those that the host system supports,
and ensure that ->sfp_interfaces is cleared when a SFP is removed. We
then add phylink_sfp_select_interface_speed() which will select an
appropriate interface from ->sfp_interfaces for the speed, and use that
in our phylink_ethtool_ksettings_set() when a SFP bus is present on a
directly connected host (not with a PHY.)
====================

Link: https://patch.msgid.link/aGT_hoBELDysGbrp@shell.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 54 insertions, 6 deletions

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 67218d278ce6..f5473510b762 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -2709,6 +2709,39 @@ static phy_interface_t phylink_sfp_select_interface(struct phylink *pl,
 	return interface;
 }
 
+static phy_interface_t phylink_sfp_select_interface_speed(struct phylink *pl,
+							  u32 speed)
+{
+	phy_interface_t best_interface = PHY_INTERFACE_MODE_NA;
+	phy_interface_t interface;
+	u32 max_speed;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(phylink_sfp_interface_preference); i++) {
+		interface = phylink_sfp_interface_preference[i];
+		if (!test_bit(interface, pl->sfp_interfaces))
+			continue;
+
+		max_speed = phylink_interface_max_speed(interface);
+
+		/* The logic here is: if speed == max_speed, then we've found
+		 * the best interface. Otherwise we find the interface that
+		 * can just support the requested speed.
+		 */
+		if (max_speed >= speed)
+			best_interface = interface;
+
+		if (max_speed <= speed)
+			break;
+	}
+
+	if (best_interface == PHY_INTERFACE_MODE_NA)
+		phylink_err(pl, "selection of interface failed, speed %u\n",
+			    speed);
+
+	return best_interface;
+}
+
 static void phylink_merge_link_mode(unsigned long *dst, const unsigned long *b)
 {
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(mask);
@@ -2911,8 +2944,14 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 	 * link can be configured correctly.
 	 */
 	if (pl->sfp_bus) {
-		config.interface = phylink_sfp_select_interface(pl,
+		if (kset->base.autoneg == AUTONEG_ENABLE)
+			config.interface =
+				phylink_sfp_select_interface(pl,
 							config.advertising);
+		else
+			config.interface =
+				phylink_sfp_select_interface_speed(pl,
+							config.speed);
 		if (config.interface == PHY_INTERFACE_MODE_NA)
 			return -EINVAL;
 
@@ -3536,6 +3575,8 @@ static int phylink_sfp_config_phy(struct phylink *pl, struct phy_device *phy)
 	struct phylink_link_state config;
 	int ret;
 
+	/* We're not using pl->sfp_interfaces, so clear it. */
+	phy_interface_zero(pl->sfp_interfaces);
 	linkmode_copy(support, phy->supported);
 
 	memset(&config, 0, sizeof(config));
@@ -3582,7 +3623,6 @@ static int phylink_sfp_config_phy(struct phylink *pl, struct phy_device *phy)
 static int phylink_sfp_config_optical(struct phylink *pl)
 {
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(support);
-	DECLARE_PHY_INTERFACE_MASK(interfaces);
 	struct phylink_link_state config;
 	phy_interface_t interface;
 	int ret;
@@ -3596,9 +3636,9 @@ static int phylink_sfp_config_optical(struct phylink *pl)
 	/* Find the union of the supported interfaces by the PCS/MAC and
 	 * the SFP module.
 	 */
-	phy_interface_and(interfaces, pl->config->supported_interfaces,
+	phy_interface_and(pl->sfp_interfaces, pl->config->supported_interfaces,
 			  pl->sfp_interfaces);
-	if (phy_interface_empty(interfaces)) {
+	if (phy_interface_empty(pl->sfp_interfaces)) {
 		phylink_err(pl, "unsupported SFP module: no common interface modes\n");
 		return -EINVAL;
 	}
@@ -3614,14 +3654,14 @@ static int phylink_sfp_config_optical(struct phylink *pl)
 	 * mask to only those link modes that can be supported.
 	 */
 	ret = phylink_validate_mask(pl, NULL, pl->sfp_support, &config,
-				    interfaces);
+				    pl->sfp_interfaces);
 	if (ret) {
 		phylink_err(pl, "unsupported SFP module: validation with support %*pb failed\n",
 			    __ETHTOOL_LINK_MODE_MASK_NBITS, support);
 		return ret;
 	}
 
-	interface = phylink_choose_sfp_interface(pl, interfaces);
+	interface = phylink_choose_sfp_interface(pl, pl->sfp_interfaces);
 	if (interface == PHY_INTERFACE_MODE_NA) {
 		phylink_err(pl, "failed to select SFP interface\n");
 		return -EINVAL;
@@ -3674,6 +3714,13 @@ static int phylink_sfp_module_insert(void *upstream,
 	return phylink_sfp_config_optical(pl);
 }
 
+static void phylink_sfp_module_remove(void *upstream)
+{
+	struct phylink *pl = upstream;
+
+	phy_interface_zero(pl->sfp_interfaces);
+}
+
 static int phylink_sfp_module_start(void *upstream)
 {
 	struct phylink *pl = upstream;
@@ -3758,6 +3805,7 @@ static const struct sfp_upstream_ops sfp_phylink_ops = {
 	.attach = phylink_sfp_attach,
 	.detach = phylink_sfp_detach,
 	.module_insert = phylink_sfp_module_insert,
+	.module_remove = phylink_sfp_module_remove,
 	.module_start = phylink_sfp_module_start,
 	.module_stop = phylink_sfp_module_stop,
 	.link_up = phylink_sfp_link_up,