[PATCH net-next 00/14] Phylink PCS updates

[PATCH net-next 00/14] Phylink PCS updates

[Russell King - ARM Linux admin]

Hi,

This series updates the rudimentary phylink PCS support with the
results of the last four months of development of that.  Phylink
PCS support was initially added back at the end of March, when it
became clear that the current approach of treating everything at
the MAC end as being part of the MAC was inadequate.

However, this rudimentary implementation was fine initially for
mvneta and similar, but in practice had a fair number of issues,
particularly when ethtool interfaces were used to change various
link properties.

It became apparent that relying on the phylink_config structure for
the PCS was also bad when it became clear that the same PCS was used
in DSA drivers as well as in NXPs other offerings, and there was a
desire to re-use that code.

It also became apparent that splitting the "configuration" step on
an interface mode configuration between the MAC and PCS using just
mac_config() and pcs_config() methods was not sufficient for some
setups, as the MAC needed to be "taken down" prior to making changes,
and once all settings were complete, the MAC could only then be
resumed.

This series addresses these points, progressing PCS support, and
has been developed with mvneta and DPAA2 setups, with work on both
those drivers to prove this approach.  It has been rigorously tested
with mvneta, as that provides the most flexibility for testing the
various code paths.

To solve the phylink_config reuse problem, we introduce a struct
phylink_pcs, which contains the minimal information necessary, and it
is intended that this is embedded in the PCS private data structure.

To solve the interface mode configuration problem, we introduce two
new MAC methods, mac_prepare() and mac_finish() which wrap the entire
interface mode configuration only.  This has the additional benefit of
relieving MAC drivers from working out whether an interface change has
occurred, and whether they need to do some major work.

I have not yet updated all the interface documentation for these
changes yet, that work remains, but this patch set is provided in the
hope that those working on PCS support in NXP will find this useful.

Since there is a lot of change here, this is the reason why I strongly
advise that everyone has converted to the mac_link_up() way of
configuring the link parameters when the link comes up, rather than
the old way of using mac_config() - especially as splitting the PCS
changes how and when phylink calls mac_config(). Although no change
for existing users is intended, that is something I no longer am able
to test.

Changes since RFC:
- fix bisect build failure
- add patch to use config.an_enabled
- rename phylink_config_interface to phylink_major_reconfig
- add expanded documentation for phylink_set_pcs()

 drivers/net/phy/phylink.c | 372 ++++++++++++++++++++++++++++++++--------------
 include/linux/phylink.h   | 103 ++++++++++---
 2 files changed, 344 insertions(+), 131 deletions(-)

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

[PATCH net-next 01/14] net: phylink: update ethtool reporting for fixed-link modes

[Russell King]

Comparing the ethtool output from phylink and non-phylink fixed-link
setups shows that we have some differences:

- The "auto-negotiation" fields are different; phylink reports these
  as "No", non-phylink reports these as "Yes" for the supported and
  advertising masks.
- The link partner advertisement is set to the link speed with non-
  phylink, but phylink leaves this unset, causing all link partner
  fields to be omitted.

The phylink ethtool output also disagrees with the software emulated
PHY dump via the MII registers.

Update the phylink fixed-link parsing code so that we better reflect
the behaviour of the non-phylink code that this facility replaces, and
bring the ethtool interface more into line with the report from via the
MII interface.

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

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index dae6c8b51d7f..0fd5a11966aa 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -241,8 +241,10 @@ static int phylink_parse_fixedlink(struct phylink *pl,
 	phylink_set(pl->supported, MII);
 	phylink_set(pl->supported, Pause);
 	phylink_set(pl->supported, Asym_Pause);
+	phylink_set(pl->supported, Autoneg);
 	if (s) {
 		__set_bit(s->bit, pl->supported);
+		__set_bit(s->bit, pl->link_config.lp_advertising);
 	} else {
 		phylink_warn(pl, "fixed link %s duplex %dMbps not recognised\n",
 			     pl->link_config.duplex == DUPLEX_FULL ? "full" : "half",
-- 
2.20.1

[PATCH net-next 02/14] net: phylink: rejig link state tracking

[Russell King]

Rejig the link state tracking, so that we can use the current state
in a future patch.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 0fd5a11966aa..b36e0315f0b1 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -578,9 +578,14 @@ static void phylink_resolve(struct work_struct *w)
 	struct phylink *pl = container_of(w, struct phylink, resolve);
 	struct phylink_link_state link_state;
 	struct net_device *ndev = pl->netdev;
-	int link_changed;
+	bool cur_link_state;
 
 	mutex_lock(&pl->state_mutex);
+	if (pl->netdev)
+		cur_link_state = netif_carrier_ok(ndev);
+	else
+		cur_link_state = pl->old_link_state;
+
 	if (pl->phylink_disable_state) {
 		pl->mac_link_dropped = false;
 		link_state.link = false;
@@ -623,12 +628,7 @@ static void phylink_resolve(struct work_struct *w)
 		}
 	}
 
-	if (pl->netdev)
-		link_changed = (link_state.link != netif_carrier_ok(ndev));
-	else
-		link_changed = (link_state.link != pl->old_link_state);
-
-	if (link_changed) {
+	if (link_state.link != cur_link_state) {
 		pl->old_link_state = link_state.link;
 		if (!link_state.link)
 			phylink_link_down(pl);
-- 
2.20.1

[PATCH net-next 03/14] net: phylink: rearrange resolve mac_config() call

[Russell King]

Use a boolean to indicate whether mac_config() should be called during
a resolution. This allows resolution to have a single location where
mac_config() will be called, which will allow us to make decisions
about how and what we do.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index b36e0315f0b1..8ffe5df5c296 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -421,13 +421,6 @@ static void phylink_mac_config(struct phylink *pl,
 	pl->mac_ops->mac_config(pl->config, pl->cur_link_an_mode, state);
 }
 
-static void phylink_mac_config_up(struct phylink *pl,
-				  const struct phylink_link_state *state)
-{
-	if (state->link)
-		phylink_mac_config(pl, state);
-}
-
 static void phylink_mac_pcs_an_restart(struct phylink *pl)
 {
 	if (pl->link_config.an_enabled &&
@@ -578,6 +571,7 @@ static void phylink_resolve(struct work_struct *w)
 	struct phylink *pl = container_of(w, struct phylink, resolve);
 	struct phylink_link_state link_state;
 	struct net_device *ndev = pl->netdev;
+	bool mac_config = false;
 	bool cur_link_state;
 
 	mutex_lock(&pl->state_mutex);
@@ -596,12 +590,12 @@ static void phylink_resolve(struct work_struct *w)
 		case MLO_AN_PHY:
 			link_state = pl->phy_state;
 			phylink_apply_manual_flow(pl, &link_state);
-			phylink_mac_config_up(pl, &link_state);
+			mac_config = link_state.link;
 			break;
 
 		case MLO_AN_FIXED:
 			phylink_get_fixed_state(pl, &link_state);
-			phylink_mac_config_up(pl, &link_state);
+			mac_config = link_state.link;
 			break;
 
 		case MLO_AN_INBAND:
@@ -619,15 +613,16 @@ static void phylink_resolve(struct work_struct *w)
 				/* If we have a PHY, we need to update with
 				 * the PHY flow control bits. */
 				link_state.pause = pl->phy_state.pause;
-				phylink_apply_manual_flow(pl, &link_state);
-				phylink_mac_config(pl, &link_state);
-			} else {
-				phylink_apply_manual_flow(pl, &link_state);
+				mac_config = true;
 			}
+			phylink_apply_manual_flow(pl, &link_state);
 			break;
 		}
 	}
 
+	if (mac_config)
+		phylink_mac_config(pl, &link_state);
+
 	if (link_state.link != cur_link_state) {
 		pl->old_link_state = link_state.link;
 		if (!link_state.link)
-- 
2.20.1

[PATCH net-next 04/14] net: phylink: ensure link is down when changing interface

[Russell King]

The only PHYs that are used with phylink which change their interface
are the BCM84881 and MV88X3310 family, both of which only change their
interface modes on link-up events.  However, rather than relying upon
this behaviour by the PHY, we should give a stronger guarantee when
resolving that the link will be down whenever we change the interface
mode.  This patch implements that stronger guarantee for resolve.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 8ffe5df5c296..1507ea8a9385 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -620,8 +620,18 @@ static void phylink_resolve(struct work_struct *w)
 		}
 	}
 
-	if (mac_config)
+	if (mac_config) {
+		if (link_state.interface != pl->link_config.interface) {
+			/* The interface has changed, force the link down and
+			 * then reconfigure.
+			 */
+			if (cur_link_state) {
+				phylink_link_down(pl);
+				cur_link_state = false;
+			}
+		}
 		phylink_mac_config(pl, &link_state);
+	}
 
 	if (link_state.link != cur_link_state) {
 		pl->old_link_state = link_state.link;
-- 
2.20.1

[PATCH net-next 05/14] net: phylink: update PCS when changing interface during resolution

[Russell King]

The only PHYs that are used with phylink which change their interface
are the BCM84881 and MV88X3310 family, both of which only change their
interface modes on link-up events.  This will break when drivers are
converted to split-PCS.  Fix this.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 1507ea8a9385..f1693ec63366 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -629,8 +629,15 @@ static void phylink_resolve(struct work_struct *w)
 				phylink_link_down(pl);
 				cur_link_state = false;
 			}
+			phylink_pcs_config(pl, false, &link_state);
+			pl->link_config.interface = link_state.interface;
+		} else {
+			/* The interface remains unchanged, only the speed,
+			 * duplex or pause settings have changed. Call the
+			 * old mac_config() method to configure the MAC/PCS.
+			 */
+			phylink_mac_config(pl, &link_state);
 		}
-		phylink_mac_config(pl, &link_state);
 	}
 
 	if (link_state.link != cur_link_state) {
-- 
2.20.1

[PATCH net-next 06/14] net: phylink: avoid mac_config calls

[Russell King]

Avoid calling mac_config() when using split PCS, and the interface
remains the same.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index f1693ec63366..424a927d7889 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -631,10 +631,12 @@ static void phylink_resolve(struct work_struct *w)
 			}
 			phylink_pcs_config(pl, false, &link_state);
 			pl->link_config.interface = link_state.interface;
-		} else {
+		} else if (!pl->pcs_ops) {
 			/* The interface remains unchanged, only the speed,
 			 * duplex or pause settings have changed. Call the
-			 * old mac_config() method to configure the MAC/PCS.
+			 * old mac_config() method to configure the MAC/PCS
+			 * only if we do not have a PCS installed (an
+			 * unconverted user.)
 			 */
 			phylink_mac_config(pl, &link_state);
 		}
-- 
2.20.1

[PATCH net-next 07/14] net: phylink: simplify ksettings_set() implementation

[Russell King]

Simplify the ksettings_set() implementation to look more like phylib's
implementation; use a switch() for validating the autoneg setting, and
use the linkmode_modify() helper to set the autoneg bit in the
advertisement mask.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 424a927d7889..103d2a550415 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1314,25 +1314,24 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(support);
 	struct ethtool_link_ksettings our_kset;
 	struct phylink_link_state config;
+	const struct phy_setting *s;
 	int ret;
 
 	ASSERT_RTNL();
 
-	if (kset->base.autoneg != AUTONEG_DISABLE &&
-	    kset->base.autoneg != AUTONEG_ENABLE)
-		return -EINVAL;
-
 	linkmode_copy(support, pl->supported);
 	config = pl->link_config;
+	config.an_enabled = kset->base.autoneg == AUTONEG_ENABLE;
 
-	/* Mask out unsupported advertisements */
+	/* Mask out unsupported advertisements, and force the autoneg bit */
 	linkmode_and(config.advertising, kset->link_modes.advertising,
 		     support);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, config.advertising,
+			 config.an_enabled);
 
 	/* FIXME: should we reject autoneg if phy/mac does not support it? */
-	if (kset->base.autoneg == AUTONEG_DISABLE) {
-		const struct phy_setting *s;
-
+	switch (kset->base.autoneg) {
+	case AUTONEG_DISABLE:
 		/* Autonegotiation disabled, select a suitable speed and
 		 * duplex.
 		 */
@@ -1351,19 +1350,19 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 
 		config.speed = s->speed;
 		config.duplex = s->duplex;
-		config.an_enabled = false;
+		break;
 
-		__clear_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, config.advertising);
-	} else {
+	case AUTONEG_ENABLE:
 		/* If we have a fixed link, refuse to enable autonegotiation */
 		if (pl->cur_link_an_mode == MLO_AN_FIXED)
 			return -EINVAL;
 
 		config.speed = SPEED_UNKNOWN;
 		config.duplex = DUPLEX_UNKNOWN;
-		config.an_enabled = true;
+		break;
 
-		__set_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, config.advertising);
+	default:
+		return -EINVAL;
 	}
 
 	if (pl->phydev) {
-- 
2.20.1

[PATCH net-next 08/14] net: phylink: simplify phy case for ksettings_set method

[Russell King]

When we have a PHY attached, an ethtool ksettings_set() call only
really needs to call through to the phylib equivalent; phylib will
call back to us when the link changes so we can update our state.
Therefore, we can bypass most of our ksettings_set() call for this
case.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 104 +++++++++++++++++---------------------
 1 file changed, 47 insertions(+), 57 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 103d2a550415..967c068d16c8 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1312,13 +1312,33 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 				  const struct ethtool_link_ksettings *kset)
 {
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(support);
-	struct ethtool_link_ksettings our_kset;
 	struct phylink_link_state config;
 	const struct phy_setting *s;
-	int ret;
 
 	ASSERT_RTNL();
 
+	if (pl->phydev) {
+		/* We can rely on phylib for this update; we also do not need
+		 * to update the pl->link_config settings:
+		 * - the configuration returned via ksettings_get() will come
+		 *   from phylib whenever a PHY is present.
+		 * - link_config.interface will be updated by the PHY calling
+		 *   back via phylink_phy_change() and a subsequent resolve.
+		 * - initial link configuration for PHY mode comes from the
+		 *   last phy state updated via phylink_phy_change().
+		 * - other configuration changes (e.g. pause modes) are
+		 *   performed directly via phylib.
+		 * - if in in-band mode with a PHY, the link configuration
+		 *   is passed on the link from the PHY, and all of
+		 *   link_config.{speed,duplex,an_enabled,pause} are not used.
+		 * - the only possible use would be link_config.advertising
+		 *   pause modes when in 1000base-X mode with a PHY, but in
+		 *   the presence of a PHY, this should not be changed as that
+		 *   should be determined from the media side advertisement.
+		 */
+		return phy_ethtool_ksettings_set(pl->phydev, kset);
+	}
+
 	linkmode_copy(support, pl->supported);
 	config = pl->link_config;
 	config.an_enabled = kset->base.autoneg == AUTONEG_ENABLE;
@@ -1365,65 +1385,35 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 		return -EINVAL;
 	}
 
-	if (pl->phydev) {
-		/* If we have a PHY, we process the kset change via phylib.
-		 * phylib will call our link state function if the PHY
-		 * parameters have changed, which will trigger a resolve
-		 * and update the MAC configuration.
-		 */
-		our_kset = *kset;
-		linkmode_copy(our_kset.link_modes.advertising,
-			      config.advertising);
-		our_kset.base.speed = config.speed;
-		our_kset.base.duplex = config.duplex;
+	/* For a fixed link, this isn't able to change any parameters,
+	 * which just leaves inband mode.
+	 */
+	if (phylink_validate(pl, support, &config))
+		return -EINVAL;
 
-		ret = phy_ethtool_ksettings_set(pl->phydev, &our_kset);
-		if (ret)
-			return ret;
+	/* If autonegotiation is enabled, we must have an advertisement */
+	if (config.an_enabled && phylink_is_empty_linkmode(config.advertising))
+		return -EINVAL;
 
-		mutex_lock(&pl->state_mutex);
-		/* Save the new configuration */
-		linkmode_copy(pl->link_config.advertising,
-			      our_kset.link_modes.advertising);
-		pl->link_config.interface = config.interface;
-		pl->link_config.speed = our_kset.base.speed;
-		pl->link_config.duplex = our_kset.base.duplex;
-		pl->link_config.an_enabled = our_kset.base.autoneg !=
-					     AUTONEG_DISABLE;
-		mutex_unlock(&pl->state_mutex);
-	} else {
-		/* For a fixed link, this isn't able to change any parameters,
-		 * which just leaves inband mode.
+	mutex_lock(&pl->state_mutex);
+	linkmode_copy(pl->link_config.advertising, config.advertising);
+	pl->link_config.interface = config.interface;
+	pl->link_config.speed = config.speed;
+	pl->link_config.duplex = config.duplex;
+	pl->link_config.an_enabled = kset->base.autoneg !=
+				     AUTONEG_DISABLE;
+
+	if (pl->cur_link_an_mode == MLO_AN_INBAND &&
+	    !test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state)) {
+		/* If in 802.3z mode, this updates the advertisement.
+		 *
+		 * If we are in SGMII mode without a PHY, there is no
+		 * advertisement; the only thing we have is the pause
+		 * modes which can only come from a PHY.
 		 */
-		if (phylink_validate(pl, support, &config))
-			return -EINVAL;
-
-		/* If autonegotiation is enabled, we must have an advertisement */
-		if (config.an_enabled &&
-		    phylink_is_empty_linkmode(config.advertising))
-			return -EINVAL;
-
-		mutex_lock(&pl->state_mutex);
-		linkmode_copy(pl->link_config.advertising, config.advertising);
-		pl->link_config.interface = config.interface;
-		pl->link_config.speed = config.speed;
-		pl->link_config.duplex = config.duplex;
-		pl->link_config.an_enabled = kset->base.autoneg !=
-					     AUTONEG_DISABLE;
-
-		if (pl->cur_link_an_mode == MLO_AN_INBAND &&
-		    !test_bit(PHYLINK_DISABLE_STOPPED,
-			      &pl->phylink_disable_state)) {
-			/* If in 802.3z mode, this updates the advertisement.
-			 *
-			 * If we are in SGMII mode without a PHY, there is no
-			 * advertisement; the only thing we have is the pause
-			 * modes which can only come from a PHY.
-			 */
-			phylink_pcs_config(pl, true, &pl->link_config);
-		}
-		mutex_unlock(&pl->state_mutex);
+		phylink_pcs_config(pl, true, &pl->link_config);
 	}
+	mutex_unlock(&pl->state_mutex);
 
 	return 0;
 }
-- 
2.20.1

[PATCH net-next 09/14] net: phylink: use config.an_enabled in ksettings_set method

[Russell King]

Rather than recomputing whether AN is enabled, use config.an_enabled.

Suggested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 967c068d16c8..6cb9ca74341b 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1400,8 +1400,7 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 	pl->link_config.interface = config.interface;
 	pl->link_config.speed = config.speed;
 	pl->link_config.duplex = config.duplex;
-	pl->link_config.an_enabled = kset->base.autoneg !=
-				     AUTONEG_DISABLE;
+	pl->link_config.an_enabled = config.an_enabled;
 
 	if (pl->cur_link_an_mode == MLO_AN_INBAND &&
 	    !test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state)) {
-- 
2.20.1

[PATCH net-next 10/14] net: phylink: simplify fixed-link case for ksettings_set method

[Russell King]

For fixed links, we only allow the current settings, so this should be
a matter of merely rejecting an attempt to change the settings.  If the
settings agree, then there is nothing more we need to do.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 6cb9ca74341b..452d509803ca 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1360,22 +1360,31 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 		if (!s)
 			return -EINVAL;
 
-		/* If we have a fixed link (as specified by firmware), refuse
-		 * to change link parameters.
+		/* If we have a fixed link, refuse to change link parameters.
+		 * If the link parameters match, accept them but do nothing.
 		 */
-		if (pl->cur_link_an_mode == MLO_AN_FIXED &&
-		    (s->speed != pl->link_config.speed ||
-		     s->duplex != pl->link_config.duplex))
-			return -EINVAL;
+		if (pl->cur_link_an_mode == MLO_AN_FIXED) {
+			if (s->speed != pl->link_config.speed ||
+			    s->duplex != pl->link_config.duplex)
+				return -EINVAL;
+			return 0;
+		}
 
 		config.speed = s->speed;
 		config.duplex = s->duplex;
 		break;
 
 	case AUTONEG_ENABLE:
-		/* If we have a fixed link, refuse to enable autonegotiation */
-		if (pl->cur_link_an_mode == MLO_AN_FIXED)
-			return -EINVAL;
+		/* If we have a fixed link, allow autonegotiation (since that
+		 * is our default case) but do not allow the advertisement to
+		 * be changed. If the advertisement matches, simply return.
+		 */
+		if (pl->cur_link_an_mode == MLO_AN_FIXED) {
+			if (!linkmode_equal(config.advertising,
+					    pl->link_config.advertising))
+				return -EINVAL;
+			return 0;
+		}
 
 		config.speed = SPEED_UNKNOWN;
 		config.duplex = DUPLEX_UNKNOWN;
@@ -1385,8 +1394,8 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 		return -EINVAL;
 	}
 
-	/* For a fixed link, this isn't able to change any parameters,
-	 * which just leaves inband mode.
+	/* We have ruled out the case with a PHY attached, and the
+	 * fixed-link cases.  All that is left are in-band links.
 	 */
 	if (phylink_validate(pl, support, &config))
 		return -EINVAL;
-- 
2.20.1

[PATCH net-next 11/14] net: phylink: in-band pause mode advertisement update for PCS

[Russell King]

Re-code the pause in-band advertisement update in light of the addition
of PCS support, so that we perform the minimum required; only the PCS
configuration function needs to be called in this case, followed by the
request to trigger a restart of negotiation if the programmed
advertisement changed.

We need to change the pcs_config() signature to pass whether resolved
pause should be passed to the MAC for setups such as mvneta and mvpp2
where doing so overrides the MAC manual flow controls.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 55 ++++++++++++++++++++++++++++++++++++---
 include/linux/phylink.h   |  7 +++--
 2 files changed, 56 insertions(+), 6 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 452d509803ca..84a426401102 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -441,7 +441,9 @@ static void phylink_pcs_config(struct phylink *pl, bool force_restart,
 	if (pl->pcs_ops && pl->pcs_ops->pcs_config(pl->config,
 						   pl->cur_link_an_mode,
 						   state->interface,
-						   state->advertising))
+						   state->advertising,
+						   !!(pl->link_config.pause &
+						      MLO_PAUSE_AN)))
 		restart = true;
 
 	phylink_mac_config(pl, state);
@@ -450,6 +452,49 @@ static void phylink_pcs_config(struct phylink *pl, bool force_restart,
 		phylink_mac_pcs_an_restart(pl);
 }
 
+/*
+ * Reconfigure for a change of inband advertisement.
+ * If we have a separate PCS, we only need to call its pcs_config() method,
+ * and then restart AN if it indicates something changed. Otherwise, we do
+ * the full MAC reconfiguration.
+ */
+static int phylink_change_inband_advert(struct phylink *pl)
+{
+	int ret;
+
+	if (test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state))
+		return 0;
+
+	if (!pl->pcs_ops) {
+		/* Legacy method */
+		phylink_mac_config(pl, &pl->link_config);
+		phylink_mac_pcs_an_restart(pl);
+		return 0;
+	}
+
+	phylink_dbg(pl, "%s: mode=%s/%s adv=%*pb pause=%02x\n", __func__,
+		    phylink_an_mode_str(pl->cur_link_an_mode),
+		    phy_modes(pl->link_config.interface),
+		    __ETHTOOL_LINK_MODE_MASK_NBITS, pl->link_config.advertising,
+		    pl->link_config.pause);
+
+	/* Modern PCS-based method; update the advert at the PCS, and
+	 * restart negotiation if the pcs_config() helper indicates that
+	 * the programmed advertisement has changed.
+	 */
+	ret = pl->pcs_ops->pcs_config(pl->config, pl->cur_link_an_mode,
+				      pl->link_config.interface,
+				      pl->link_config.advertising,
+				      !!(pl->link_config.pause & MLO_PAUSE_AN));
+	if (ret < 0)
+		return ret;
+
+	if (ret > 0)
+		phylink_mac_pcs_an_restart(pl);
+
+	return 0;
+}
+
 static void phylink_mac_pcs_get_state(struct phylink *pl,
 				      struct phylink_link_state *state)
 {
@@ -1524,9 +1569,11 @@ int phylink_ethtool_set_pauseparam(struct phylink *pl,
 
 	config->pause = pause_state;
 
-	if (!pl->phydev && !test_bit(PHYLINK_DISABLE_STOPPED,
-				     &pl->phylink_disable_state))
-		phylink_pcs_config(pl, true, &pl->link_config);
+	/* Update our in-band advertisement, triggering a renegotiation if
+	 * the advertisement changed.
+	 */
+	if (!pl->phydev)
+		phylink_change_inband_advert(pl);
 
 	mutex_unlock(&pl->state_mutex);
 
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index b32b8b45421b..d9913d8e6b91 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -286,7 +286,8 @@ struct phylink_pcs_ops {
 			      struct phylink_link_state *state);
 	int (*pcs_config)(struct phylink_config *config, unsigned int mode,
 			  phy_interface_t interface,
-			  const unsigned long *advertising);
+			  const unsigned long *advertising,
+			  bool permit_pause_to_mac);
 	void (*pcs_an_restart)(struct phylink_config *config);
 	void (*pcs_link_up)(struct phylink_config *config, unsigned int mode,
 			    phy_interface_t interface, int speed, int duplex);
@@ -317,9 +318,11 @@ void pcs_get_state(struct phylink_config *config,
  * @mode: one of %MLO_AN_FIXED, %MLO_AN_PHY, %MLO_AN_INBAND.
  * @interface: interface mode to be used
  * @advertising: adertisement ethtool link mode mask
+ * @permit_pause_to_mac: permit forwarding pause resolution to MAC
  *
  * Configure the PCS for the operating mode, the interface mode, and set
- * the advertisement mask.
+ * the advertisement mask. @permit_pause_to_mac indicates whether the
+ * hardware may forward the pause mode resolution to the MAC.
  *
  * When operating in %MLO_AN_INBAND, inband should always be enabled,
  * otherwise inband should be disabled.
-- 
2.20.1

[PATCH net-next 12/14] net: phylink: re-implement interface configuration with PCS

[Russell King]

With PCS support, how we implement interface reconfiguration (or other
major reconfiguration) is not up to the job; we end up reconfiguring
the PCS for an interface change while the link could potentially be up.
In order to solve this, add two additional MAC methods for major
configuration, one to prepare for the change, and one to finish the
change.

This allows mvneta and mvpp2 to shutdown what they require prior to the
MAC and PCS configuration calls, and then restart as appropriate.

This impacts ksettings_set(), which now needs to identify whether the
change is a minor tweak to the advertisement masks or whether the
interface mode has changed, and call the appropriate function for that
update.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 75 +++++++++++++++++++++++++++------------
 include/linux/phylink.h   | 48 +++++++++++++++++++++++++
 2 files changed, 100 insertions(+), 23 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 84a426401102..d554a0fbb4f3 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -433,23 +433,47 @@ static void phylink_mac_pcs_an_restart(struct phylink *pl)
 	}
 }
 
-static void phylink_pcs_config(struct phylink *pl, bool force_restart,
-			       const struct phylink_link_state *state)
+static void phylink_major_config(struct phylink *pl, bool restart,
+				  const struct phylink_link_state *state)
 {
-	bool restart = force_restart;
+	int err;
+
+	phylink_dbg(pl, "major config %s\n", phy_modes(state->interface));
 
-	if (pl->pcs_ops && pl->pcs_ops->pcs_config(pl->config,
-						   pl->cur_link_an_mode,
-						   state->interface,
-						   state->advertising,
-						   !!(pl->link_config.pause &
-						      MLO_PAUSE_AN)))
-		restart = true;
+	if (pl->mac_ops->mac_prepare) {
+		err = pl->mac_ops->mac_prepare(pl->config, pl->cur_link_an_mode,
+					       state->interface);
+		if (err < 0) {
+			phylink_err(pl, "mac_prepare failed: %pe\n",
+				    ERR_PTR(err));
+			return;
+		}
+	}
 
 	phylink_mac_config(pl, state);
 
+	if (pl->pcs_ops) {
+		err = pl->pcs_ops->pcs_config(pl->config, pl->cur_link_an_mode,
+					      state->interface,
+					      state->advertising,
+					      !!(pl->link_config.pause &
+						 MLO_PAUSE_AN));
+		if (err < 0)
+			phylink_err(pl, "pcs_config failed: %pe\n",
+				    ERR_PTR(err));
+		if (err > 0)
+			restart = true;
+	}
 	if (restart)
 		phylink_mac_pcs_an_restart(pl);
+
+	if (pl->mac_ops->mac_finish) {
+		err = pl->mac_ops->mac_finish(pl->config, pl->cur_link_an_mode,
+					      state->interface);
+		if (err < 0)
+			phylink_err(pl, "mac_prepare failed: %pe\n",
+				    ERR_PTR(err));
+	}
 }
 
 /*
@@ -555,7 +579,7 @@ static void phylink_mac_initial_config(struct phylink *pl, bool force_restart)
 	link_state.link = false;
 
 	phylink_apply_manual_flow(pl, &link_state);
-	phylink_pcs_config(pl, force_restart, &link_state);
+	phylink_major_config(pl, force_restart, &link_state);
 }
 
 static const char *phylink_pause_to_str(int pause)
@@ -674,7 +698,7 @@ static void phylink_resolve(struct work_struct *w)
 				phylink_link_down(pl);
 				cur_link_state = false;
 			}
-			phylink_pcs_config(pl, false, &link_state);
+			phylink_major_config(pl, false, &link_state);
 			pl->link_config.interface = link_state.interface;
 		} else if (!pl->pcs_ops) {
 			/* The interface remains unchanged, only the speed,
@@ -1450,21 +1474,26 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
 		return -EINVAL;
 
 	mutex_lock(&pl->state_mutex);
-	linkmode_copy(pl->link_config.advertising, config.advertising);
-	pl->link_config.interface = config.interface;
 	pl->link_config.speed = config.speed;
 	pl->link_config.duplex = config.duplex;
 	pl->link_config.an_enabled = config.an_enabled;
 
-	if (pl->cur_link_an_mode == MLO_AN_INBAND &&
-	    !test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state)) {
-		/* If in 802.3z mode, this updates the advertisement.
-		 *
-		 * If we are in SGMII mode without a PHY, there is no
-		 * advertisement; the only thing we have is the pause
-		 * modes which can only come from a PHY.
-		 */
-		phylink_pcs_config(pl, true, &pl->link_config);
+	if (pl->link_config.interface != config.interface) {
+		/* The interface changed, e.g. 1000base-X <-> 2500base-X */
+		/* We need to force the link down, then change the interface */
+		if (pl->old_link_state) {
+			phylink_link_down(pl);
+			pl->old_link_state = false;
+		}
+		if (!test_bit(PHYLINK_DISABLE_STOPPED,
+			      &pl->phylink_disable_state))
+			phylink_major_config(pl, false, &config);
+		pl->link_config.interface = config.interface;
+		linkmode_copy(pl->link_config.advertising, config.advertising);
+	} else if (!linkmode_equal(pl->link_config.advertising,
+				   config.advertising)) {
+		linkmode_copy(pl->link_config.advertising, config.advertising);
+		phylink_change_inband_advert(pl);
 	}
 	mutex_unlock(&pl->state_mutex);
 
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index d9913d8e6b91..2f1315f32113 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -76,7 +76,9 @@ struct phylink_config {
  * struct phylink_mac_ops - MAC operations structure.
  * @validate: Validate and update the link configuration.
  * @mac_pcs_get_state: Read the current link state from the hardware.
+ * @mac_prepare: prepare for a major reconfiguration of the interface.
  * @mac_config: configure the MAC for the selected mode and state.
+ * @mac_finish: finish a major reconfiguration of the interface.
  * @mac_an_restart: restart 802.3z BaseX autonegotiation.
  * @mac_link_down: take the link down.
  * @mac_link_up: allow the link to come up.
@@ -89,8 +91,12 @@ struct phylink_mac_ops {
 			 struct phylink_link_state *state);
 	void (*mac_pcs_get_state)(struct phylink_config *config,
 				  struct phylink_link_state *state);
+	int (*mac_prepare)(struct phylink_config *config, unsigned int mode,
+			   phy_interface_t iface);
 	void (*mac_config)(struct phylink_config *config, unsigned int mode,
 			   const struct phylink_link_state *state);
+	int (*mac_finish)(struct phylink_config *config, unsigned int mode,
+			  phy_interface_t iface);
 	void (*mac_an_restart)(struct phylink_config *config);
 	void (*mac_link_down)(struct phylink_config *config, unsigned int mode,
 			      phy_interface_t interface);
@@ -145,6 +151,31 @@ void validate(struct phylink_config *config, unsigned long *supported,
 void mac_pcs_get_state(struct phylink_config *config,
 		       struct phylink_link_state *state);
 
+/**
+ * mac_prepare() - prepare to change the PHY interface mode
+ * @config: a pointer to a &struct phylink_config.
+ * @mode: one of %MLO_AN_FIXED, %MLO_AN_PHY, %MLO_AN_INBAND.
+ * @iface: interface mode to switch to
+ *
+ * phylink will call this method at the beginning of a full initialisation
+ * of the link, which includes changing the interface mode or at initial
+ * startup time. It may be called for the current mode. The MAC driver
+ * should perform whatever actions are required, e.g. disabling the
+ * Serdes PHY.
+ *
+ * This will be the first call in the sequence:
+ * - mac_prepare()
+ * - mac_config()
+ * - pcs_config()
+ * - possible pcs_an_restart()
+ * - mac_finish()
+ *
+ * Returns zero on success, or negative errno on failure which will be
+ * reported to the kernel log.
+ */
+int mac_prepare(struct phylink_config *config, unsigned int mode,
+		phy_interface_t iface);
+
 /**
  * mac_config() - configure the MAC for the selected mode and state
  * @config: a pointer to a &struct phylink_config.
@@ -220,6 +251,23 @@ void mac_pcs_get_state(struct phylink_config *config,
 void mac_config(struct phylink_config *config, unsigned int mode,
 		const struct phylink_link_state *state);
 
+/**
+ * mac_finish() - finish a to change the PHY interface mode
+ * @config: a pointer to a &struct phylink_config.
+ * @mode: one of %MLO_AN_FIXED, %MLO_AN_PHY, %MLO_AN_INBAND.
+ * @iface: interface mode to switch to
+ *
+ * phylink will call this if it called mac_prepare() to allow the MAC to
+ * complete any necessary steps after the MAC and PCS have been configured
+ * for the @mode and @iface. E.g. a MAC driver may wish to re-enable the
+ * Serdes PHY here if it was previously disabled by mac_prepare().
+ *
+ * Returns zero on success, or negative errno on failure which will be
+ * reported to the kernel log.
+ */
+int mac_finish(struct phylink_config *config, unsigned int mode,
+		phy_interface_t iface);
+
 /**
  * mac_an_restart() - restart 802.3z BaseX autonegotiation
  * @config: a pointer to a &struct phylink_config.
-- 
2.20.1

[PATCH net-next 13/14] net: phylink: add struct phylink_pcs

[Russell King]

Add a way for MAC PCS to have private data while keeping independence
from struct phylink_config, which is used for the MAC itself. We need
this independence as we will have stand-alone code for PCS that is
independent of the MAC.  Introduce struct phylink_pcs, which is
designed to be embedded in a driver private data structure.

This structure does not include a mdio_device as there are PCS
implementations such as the Marvell DSA and network drivers where this
is not necessary.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 34 ++++++++++++++++++++++-------
 include/linux/phylink.h   | 45 ++++++++++++++++++++++++++-------------
 2 files changed, 56 insertions(+), 23 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index d554a0fbb4f3..b57cd2142786 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -43,6 +43,7 @@ struct phylink {
 	const struct phylink_mac_ops *mac_ops;
 	const struct phylink_pcs_ops *pcs_ops;
 	struct phylink_config *config;
+	struct phylink_pcs *pcs;
 	struct device *dev;
 	unsigned int old_link_state:1;
 
@@ -427,7 +428,7 @@ static void phylink_mac_pcs_an_restart(struct phylink *pl)
 	    phy_interface_mode_is_8023z(pl->link_config.interface) &&
 	    phylink_autoneg_inband(pl->cur_link_an_mode)) {
 		if (pl->pcs_ops)
-			pl->pcs_ops->pcs_an_restart(pl->config);
+			pl->pcs_ops->pcs_an_restart(pl->pcs);
 		else
 			pl->mac_ops->mac_an_restart(pl->config);
 	}
@@ -453,7 +454,7 @@ static void phylink_major_config(struct phylink *pl, bool restart,
 	phylink_mac_config(pl, state);
 
 	if (pl->pcs_ops) {
-		err = pl->pcs_ops->pcs_config(pl->config, pl->cur_link_an_mode,
+		err = pl->pcs_ops->pcs_config(pl->pcs, pl->cur_link_an_mode,
 					      state->interface,
 					      state->advertising,
 					      !!(pl->link_config.pause &
@@ -506,7 +507,7 @@ static int phylink_change_inband_advert(struct phylink *pl)
 	 * restart negotiation if the pcs_config() helper indicates that
 	 * the programmed advertisement has changed.
 	 */
-	ret = pl->pcs_ops->pcs_config(pl->config, pl->cur_link_an_mode,
+	ret = pl->pcs_ops->pcs_config(pl->pcs, pl->cur_link_an_mode,
 				      pl->link_config.interface,
 				      pl->link_config.advertising,
 				      !!(pl->link_config.pause & MLO_PAUSE_AN));
@@ -533,7 +534,7 @@ static void phylink_mac_pcs_get_state(struct phylink *pl,
 	state->link = 1;
 
 	if (pl->pcs_ops)
-		pl->pcs_ops->pcs_get_state(pl->config, state);
+		pl->pcs_ops->pcs_get_state(pl->pcs, state);
 	else
 		pl->mac_ops->mac_pcs_get_state(pl->config, state);
 }
@@ -604,7 +605,7 @@ static void phylink_link_up(struct phylink *pl,
 	pl->cur_interface = link_state.interface;
 
 	if (pl->pcs_ops && pl->pcs_ops->pcs_link_up)
-		pl->pcs_ops->pcs_link_up(pl->config, pl->cur_link_an_mode,
+		pl->pcs_ops->pcs_link_up(pl->pcs, pl->cur_link_an_mode,
 					 pl->cur_interface,
 					 link_state.speed, link_state.duplex);
 
@@ -863,11 +864,26 @@ struct phylink *phylink_create(struct phylink_config *config,
 }
 EXPORT_SYMBOL_GPL(phylink_create);
 
-void phylink_add_pcs(struct phylink *pl, const struct phylink_pcs_ops *ops)
+/**
+ * phylink_set_pcs() - set the current PCS for phylink to use
+ * @pl: a pointer to a &struct phylink returned from phylink_create()
+ * @pcs: a pointer to the &struct phylink_pcs
+ *
+ * Bind the MAC PCS to phylink.  This may be called after phylink_create(),
+ * in mac_prepare() or mac_config() methods if it is desired to dynamically
+ * change the PCS.
+ *
+ * Please note that there are behavioural changes with the mac_config()
+ * callback if a PCS is present (denoting a newer setup) so removing a PCS
+ * is not supported, and if a PCS is going to be used, it must be registered
+ * by calling phylink_set_pcs() at the latest in the first mac_config() call.
+ */
+void phylink_set_pcs(struct phylink *pl, struct phylink_pcs *pcs)
 {
-	pl->pcs_ops = ops;
+	pl->pcs = pcs;
+	pl->pcs_ops = pcs->ops;
 }
-EXPORT_SYMBOL_GPL(phylink_add_pcs);
+EXPORT_SYMBOL_GPL(phylink_set_pcs);
 
 /**
  * phylink_destroy() - cleanup and destroy the phylink instance
@@ -1212,6 +1228,8 @@ void phylink_start(struct phylink *pl)
 		break;
 	case MLO_AN_INBAND:
 		poll |= pl->config->pcs_poll;
+		if (pl->pcs)
+			poll |= pl->pcs->poll;
 		break;
 	}
 	if (poll)
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index 2f1315f32113..057f78263a46 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -321,6 +321,21 @@ void mac_link_up(struct phylink_config *config, struct phy_device *phy,
 		 int speed, int duplex, bool tx_pause, bool rx_pause);
 #endif
 
+struct phylink_pcs_ops;
+
+/**
+ * struct phylink_pcs - PHYLINK PCS instance
+ * @ops: a pointer to the &struct phylink_pcs_ops structure
+ * @poll: poll the PCS for link changes
+ *
+ * This structure is designed to be embedded within the PCS private data,
+ * and will be passed between phylink and the PCS.
+ */
+struct phylink_pcs {
+	const struct phylink_pcs_ops *ops;
+	bool poll;
+};
+
 /**
  * struct phylink_pcs_ops - MAC PCS operations structure.
  * @pcs_get_state: read the current MAC PCS link state from the hardware.
@@ -330,21 +345,21 @@ void mac_link_up(struct phylink_config *config, struct phy_device *phy,
  *               (where necessary).
  */
 struct phylink_pcs_ops {
-	void (*pcs_get_state)(struct phylink_config *config,
+	void (*pcs_get_state)(struct phylink_pcs *pcs,
 			      struct phylink_link_state *state);
-	int (*pcs_config)(struct phylink_config *config, unsigned int mode,
+	int (*pcs_config)(struct phylink_pcs *pcs, unsigned int mode,
 			  phy_interface_t interface,
 			  const unsigned long *advertising,
 			  bool permit_pause_to_mac);
-	void (*pcs_an_restart)(struct phylink_config *config);
-	void (*pcs_link_up)(struct phylink_config *config, unsigned int mode,
+	void (*pcs_an_restart)(struct phylink_pcs *pcs);
+	void (*pcs_link_up)(struct phylink_pcs *pcs, unsigned int mode,
 			    phy_interface_t interface, int speed, int duplex);
 };
 
 #if 0 /* For kernel-doc purposes only. */
 /**
  * pcs_get_state() - Read the current inband link state from the hardware
- * @config: a pointer to a &struct phylink_config.
+ * @pcs: a pointer to a &struct phylink_pcs.
  * @state: a pointer to a &struct phylink_link_state.
  *
  * Read the current inband link state from the MAC PCS, reporting the
@@ -357,12 +372,12 @@ struct phylink_pcs_ops {
  * When present, this overrides mac_pcs_get_state() in &struct
  * phylink_mac_ops.
  */
-void pcs_get_state(struct phylink_config *config,
+void pcs_get_state(struct phylink_pcs *pcs,
 		   struct phylink_link_state *state);
 
 /**
  * pcs_config() - Configure the PCS mode and advertisement
- * @config: a pointer to a &struct phylink_config.
+ * @pcs: a pointer to a &struct phylink_pcs.
  * @mode: one of %MLO_AN_FIXED, %MLO_AN_PHY, %MLO_AN_INBAND.
  * @interface: interface mode to be used
  * @advertising: adertisement ethtool link mode mask
@@ -382,21 +397,21 @@ void pcs_get_state(struct phylink_config *config,
  *
  * For most 10GBASE-R, there is no advertisement.
  */
-int (*pcs_config)(struct phylink_config *config, unsigned int mode,
-		  phy_interface_t interface, const unsigned long *advertising);
+int pcs_config(struct phylink_pcs *pcs, unsigned int mode,
+	       phy_interface_t interface, const unsigned long *advertising);
 
 /**
  * pcs_an_restart() - restart 802.3z BaseX autonegotiation
- * @config: a pointer to a &struct phylink_config.
+ * @pcs: a pointer to a &struct phylink_pcs.
  *
  * When PCS ops are present, this overrides mac_an_restart() in &struct
  * phylink_mac_ops.
  */
-void (*pcs_an_restart)(struct phylink_config *config);
+void pcs_an_restart(struct phylink_pcs *pcs);
 
 /**
  * pcs_link_up() - program the PCS for the resolved link configuration
- * @config: a pointer to a &struct phylink_config.
+ * @pcs: a pointer to a &struct phylink_pcs.
  * @mode: link autonegotiation mode
  * @interface: link &typedef phy_interface_t mode
  * @speed: link speed
@@ -407,14 +422,14 @@ void (*pcs_an_restart)(struct phylink_config *config);
  * mode without in-band AN needs to be manually configured for the link
  * and duplex setting. Otherwise, this should be a no-op.
  */
-void (*pcs_link_up)(struct phylink_config *config, unsigned int mode,
-		    phy_interface_t interface, int speed, int duplex);
+void pcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
+		 phy_interface_t interface, int speed, int duplex);
 #endif
 
 struct phylink *phylink_create(struct phylink_config *, struct fwnode_handle *,
 			       phy_interface_t iface,
 			       const struct phylink_mac_ops *mac_ops);
-void phylink_add_pcs(struct phylink *, const struct phylink_pcs_ops *ops);
+void phylink_set_pcs(struct phylink *, struct phylink_pcs *pcs);
 void phylink_destroy(struct phylink *);
 
 int phylink_connect_phy(struct phylink *, struct phy_device *);
-- 
2.20.1

[PATCH net-next 14/14] net: phylink: add interface to configure clause 22 PCS PHY

[Russell King]

Add an interface to configure the advertisement for a clause 22 PCS
PHY, and set the AN enable flag in the BMCR appropriately.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 37 +++++++++++++++++++++++++++++++++++++
 include/linux/phylink.h   |  3 +++
 2 files changed, 40 insertions(+)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index b57cd2142786..32b4bd6a5b55 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -2442,6 +2442,43 @@ int phylink_mii_c22_pcs_set_advertisement(struct mdio_device *pcs,
 }
 EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_set_advertisement);
 
+/**
+ * phylink_mii_c22_pcs_config() - configure clause 22 PCS
+ * @pcs: a pointer to a &struct mdio_device.
+ * @mode: link autonegotiation mode
+ * @interface: the PHY interface mode being configured
+ * @advertising: the ethtool advertisement mask
+ *
+ * Configure a Clause 22 PCS PHY with the appropriate negotiation
+ * parameters for the @mode, @interface and @advertising parameters.
+ * Returns negative error number on failure, zero if the advertisement
+ * has not changed, or positive if there is a change.
+ */
+int phylink_mii_c22_pcs_config(struct mdio_device *pcs, unsigned int mode,
+			       phy_interface_t interface,
+			       const unsigned long *advertising)
+{
+	bool changed;
+	u16 bmcr;
+	int ret;
+
+	ret = phylink_mii_c22_pcs_set_advertisement(pcs, interface,
+						    advertising);
+	if (ret < 0)
+		return ret;
+
+	changed = ret > 0;
+
+	bmcr = mode == MLO_AN_INBAND ? BMCR_ANENABLE : 0;
+	ret = mdiobus_modify(pcs->bus, pcs->addr, MII_BMCR,
+			     BMCR_ANENABLE, bmcr);
+	if (ret < 0)
+		return ret;
+
+	return changed ? 1 : 0;
+}
+EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_config);
+
 /**
  * phylink_mii_c22_pcs_an_restart() - restart 802.3z autonegotiation
  * @pcs: a pointer to a &struct mdio_device.
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index 057f78263a46..1aad2aea4610 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -478,6 +478,9 @@ void phylink_mii_c22_pcs_get_state(struct mdio_device *pcs,
 int phylink_mii_c22_pcs_set_advertisement(struct mdio_device *pcs,
 					  phy_interface_t interface,
 					  const unsigned long *advertising);
+int phylink_mii_c22_pcs_config(struct mdio_device *pcs, unsigned int mode,
+			       phy_interface_t interface,
+			       const unsigned long *advertising);
 void phylink_mii_c22_pcs_an_restart(struct mdio_device *pcs);
 
 void phylink_mii_c45_pcs_get_state(struct mdio_device *pcs,
-- 
2.20.1

Re: [PATCH net-next 00/14] Phylink PCS updates

[David Miller]

From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Date: Tue, 21 Jul 2020 12:01:52 +0100

> This series updates the rudimentary phylink PCS support with the
> results of the last four months of development of that.  Phylink
> PCS support was initially added back at the end of March, when it
> became clear that the current approach of treating everything at
> the MAC end as being part of the MAC was inadequate.
> 
> However, this rudimentary implementation was fine initially for
> mvneta and similar, but in practice had a fair number of issues,
> particularly when ethtool interfaces were used to change various
> link properties.
> 
> It became apparent that relying on the phylink_config structure for
> the PCS was also bad when it became clear that the same PCS was used
> in DSA drivers as well as in NXPs other offerings, and there was a
> desire to re-use that code.
> 
> It also became apparent that splitting the "configuration" step on
> an interface mode configuration between the MAC and PCS using just
> mac_config() and pcs_config() methods was not sufficient for some
> setups, as the MAC needed to be "taken down" prior to making changes,
> and once all settings were complete, the MAC could only then be
> resumed.
> 
> This series addresses these points, progressing PCS support, and
> has been developed with mvneta and DPAA2 setups, with work on both
> those drivers to prove this approach.  It has been rigorously tested
> with mvneta, as that provides the most flexibility for testing the
> various code paths.
 ...

Series applied, thank you.