[PATCH net-next 0/5] mvpp2 phylink fixes

[PATCH net-next 0/5] mvpp2 phylink fixes

[Russell King - ARM Linux admin]

Hi,

Having spent a while debugging issues with Sven Auhagen, it appears
that the mvpp2 network driver's phylink support isn't quite correct.

This series fixes that up, but, despite being tested locally, by
Sven, and by Antoine, I would prefer it to be applied to net-next
so that there is time for more people to test before it hits -rc or
stable backports.

The symptoms were that although PHYs would come up, the GMAC never
reported that the link was up, or in some cases it did report link
up but packets would not flow.  Various approaches were tried to
work around that, such as switching to in-band negotiation from
PHY mode, but ultimately the problem was in the way mvpp2 was being
programmed.

This series addresses that by, essentially, making mvpp2 follow the
same implementation pattern as mvneta: we configure the GMAC in three
stages:

1) the PHY interface mode
2) the negotiation advert
3) the negotiation style

Another issue is that mvpp2 was always taking the link down each time
its mac_config method was called: this is disruptive when the link is
already up, and we're just updating settings such as flow control.
There are some circumstances where we make the call despite there
being no changes (eg, when phylink is polling a GPIO or using a custom
link state function.)

This series depends on two previous patches already sent for net-next:
  net: marvell: mvpp2: fix lack of link interrupts
  net: marvell: mvpp2: use phy_interface_mode_is_8023z() helper

There is one last patch which deals with link status interrupts, which
I'll send separately because I think there's other considerations, but
that should not hold up this series of patches.

 drivers/net/ethernet/marvell/mvpp2/mvpp2.h      |   4 +-
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 175 ++++++++++++++----------
 2 files changed, 108 insertions(+), 71 deletions(-)

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

[PATCH 1/5] net: marvell: mvpp2: phylink compliance updates

[Russell King]

Sven Auhagen reported issues with negotiation on a couple of his
platforms using a mixture of SFP and PHYs in various different
modes.  Debugging to root cause proved difficult, but essentially
the problem comes down to the mvpp2 phylink implementation being
slightly at odds with what is expected.

phylink operates in three modes: phy, fixed-link, and in-band mode.

In the first two modes, the expected behaviour from a MAC driver is
that phylink resolves the operating mode and passes the mode to the
MAC driver for it to program, including when the link should be
brought up or taken down.  This is basically the same as the libphy
approach.  This does not negate the requirement to advertise a correct
control word for interface modes that have control words where that
can be reasonably controlled.

The second mode is in-band mode, where the MAC is expected to use the
in-band control word to determine the operating mode.

The mvneta driver implements the correct pattern required to support
this: configure the port interface type separately from the in-band
mode(s).  This is now specified in the phylink documentation patches.

mvpp2 was programming in-band mode for SGMII and the 802.3z modes no
what, and avoided forcing the link up in fixed/phy modes.  This caused
a problem with some boards where the PHY is by default programmed to
enter AN bypass mode, the PHY would report that the link was up, but
the mvpp2 never completed the exchange of control word.

Another issue that mvpp2 has is it sets SGMII AN format control word
for both SGMII and 802.3z modes. The format of the control word is
defined by MVPP2_GMAC_INBAND_AN_MASK, which should be set for SGMII
and clear for 802.3z. Available Marvell documentation for earlier
GMAC implementations does not make this clear, but this has been
ascertained via extensive testing on earlier GMAC implementations,
and then confirmed with a Macchiatobin Single Shot connected to a
Clearfog: when MVPP2_GMAC_INBAND_AN_MASK is set, the clearfog does
not receive the advertised pause mode settings.

Lastly, there is no flow control in the in-band control word in Cisco
SGMII, setting the flow control autonegotiation bit even with a PHY
that has the Marvell extension to send this information does not result
in the flow control being enabled at the MAC.  We need to do this
manually using the information provided via phylink.

Re-code mvpp2's mac_config() and mac_link_up() to follow this pattern.
This allows Sven Auhagen's board and Macchiatobin to reliably bring
the link up with the 88e1512 PHY with phylink operating in PHY mode
with COMPHY built as a module but the rest of the networking built-in,
and u-boot having brought up the interface.  in-band mode requires an
additional patch to resolve another problem.

Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 97 ++++++++++++++++---------
 1 file changed, 61 insertions(+), 36 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index d8974c446f8e..c590dc7ba70a 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -4572,58 +4572,84 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 	an &= ~(MVPP2_GMAC_CONFIG_MII_SPEED | MVPP2_GMAC_CONFIG_GMII_SPEED |
 		MVPP2_GMAC_AN_SPEED_EN | MVPP2_GMAC_FC_ADV_EN |
 		MVPP2_GMAC_FC_ADV_ASM_EN | MVPP2_GMAC_FLOW_CTRL_AUTONEG |
-		MVPP2_GMAC_CONFIG_FULL_DUPLEX | MVPP2_GMAC_AN_DUPLEX_EN |
-		MVPP2_GMAC_FORCE_LINK_DOWN);
+		MVPP2_GMAC_CONFIG_FULL_DUPLEX | MVPP2_GMAC_AN_DUPLEX_EN);
 	ctrl0 &= ~MVPP2_GMAC_PORT_TYPE_MASK;
-	ctrl2 &= ~(MVPP2_GMAC_PORT_RESET_MASK | MVPP2_GMAC_PCS_ENABLE_MASK);
+	ctrl2 &= ~(MVPP2_GMAC_INBAND_AN_MASK | MVPP2_GMAC_PORT_RESET_MASK |
+		   MVPP2_GMAC_PCS_ENABLE_MASK);
+	ctrl4 &= ~(MVPP22_CTRL4_RX_FC_EN | MVPP22_CTRL4_TX_FC_EN);
 
+	/* Configure port type */
 	if (phy_interface_mode_is_8023z(state->interface)) {
-		/* 1000BaseX and 2500BaseX ports cannot negotiate speed nor can
-		 * they negotiate duplex: they are always operating with a fixed
-		 * speed of 1000/2500Mbps in full duplex, so force 1000/2500
-		 * speed and full duplex here.
-		 */
-		ctrl0 |= MVPP2_GMAC_PORT_TYPE_MASK;
-		an |= MVPP2_GMAC_CONFIG_GMII_SPEED |
-		      MVPP2_GMAC_CONFIG_FULL_DUPLEX;
-	} else if (!phy_interface_mode_is_rgmii(state->interface)) {
-		an |= MVPP2_GMAC_AN_SPEED_EN | MVPP2_GMAC_FLOW_CTRL_AUTONEG;
+		ctrl2 |= MVPP2_GMAC_PCS_ENABLE_MASK;
+		ctrl4 &= ~MVPP22_CTRL4_EXT_PIN_GMII_SEL;
+		ctrl4 |= MVPP22_CTRL4_SYNC_BYPASS_DIS |
+			 MVPP22_CTRL4_DP_CLK_SEL |
+			 MVPP22_CTRL4_QSGMII_BYPASS_ACTIVE;
+	} else if (state->interface == PHY_INTERFACE_MODE_SGMII) {
+		ctrl2 |= MVPP2_GMAC_PCS_ENABLE_MASK | MVPP2_GMAC_INBAND_AN_MASK;
+		ctrl4 &= ~MVPP22_CTRL4_EXT_PIN_GMII_SEL;
+		ctrl4 |= MVPP22_CTRL4_SYNC_BYPASS_DIS |
+			 MVPP22_CTRL4_DP_CLK_SEL |
+			 MVPP22_CTRL4_QSGMII_BYPASS_ACTIVE;
+	} else if (phy_interface_mode_is_rgmii(state->interface)) {
+		ctrl4 &= ~MVPP22_CTRL4_DP_CLK_SEL;
+		ctrl4 |= MVPP22_CTRL4_EXT_PIN_GMII_SEL |
+			 MVPP22_CTRL4_SYNC_BYPASS_DIS |
+			 MVPP22_CTRL4_QSGMII_BYPASS_ACTIVE;
 	}
 
-	if (state->duplex)
-		an |= MVPP2_GMAC_CONFIG_FULL_DUPLEX;
+	/* Configure advertisement bits */
 	if (phylink_test(state->advertising, Pause))
 		an |= MVPP2_GMAC_FC_ADV_EN;
 	if (phylink_test(state->advertising, Asym_Pause))
 		an |= MVPP2_GMAC_FC_ADV_ASM_EN;
 
-	if (phy_interface_mode_is_8023z(state->interface) ||
-	    state->interface == PHY_INTERFACE_MODE_SGMII) {
-		an |= MVPP2_GMAC_IN_BAND_AUTONEG;
-		ctrl2 |= MVPP2_GMAC_INBAND_AN_MASK | MVPP2_GMAC_PCS_ENABLE_MASK;
+	/* Configure negotiation style */
+	if (!phylink_autoneg_inband(mode)) {
+		/* Phy or fixed speed - no in-band AN */
+		if (state->duplex)
+			an |= MVPP2_GMAC_CONFIG_FULL_DUPLEX;
 
-		ctrl4 &= ~(MVPP22_CTRL4_EXT_PIN_GMII_SEL |
-			   MVPP22_CTRL4_RX_FC_EN | MVPP22_CTRL4_TX_FC_EN);
-		ctrl4 |= MVPP22_CTRL4_SYNC_BYPASS_DIS |
-			 MVPP22_CTRL4_DP_CLK_SEL |
-			 MVPP22_CTRL4_QSGMII_BYPASS_ACTIVE;
+		if (state->speed == SPEED_1000 || state->speed == SPEED_2500)
+			an |= MVPP2_GMAC_CONFIG_GMII_SPEED;
+		else if (state->speed == SPEED_100)
+			an |= MVPP2_GMAC_CONFIG_MII_SPEED;
 
 		if (state->pause & MLO_PAUSE_TX)
 			ctrl4 |= MVPP22_CTRL4_TX_FC_EN;
 		if (state->pause & MLO_PAUSE_RX)
 			ctrl4 |= MVPP22_CTRL4_RX_FC_EN;
-	} else if (phy_interface_mode_is_rgmii(state->interface)) {
-		an |= MVPP2_GMAC_IN_BAND_AUTONEG_BYPASS;
+	} else if (state->interface == PHY_INTERFACE_MODE_SGMII) {
+		/* SGMII in-band mode receives the speed and duplex from
+		 * the PHY. Flow control information is not received. */
+		an &= ~(MVPP2_GMAC_FORCE_LINK_DOWN | MVPP2_GMAC_FORCE_LINK_PASS);
+		an |= MVPP2_GMAC_IN_BAND_AUTONEG |
+		      MVPP2_GMAC_AN_SPEED_EN |
+		      MVPP2_GMAC_AN_DUPLEX_EN;
 
-		if (state->speed == SPEED_1000)
-			an |= MVPP2_GMAC_CONFIG_GMII_SPEED;
-		else if (state->speed == SPEED_100)
-			an |= MVPP2_GMAC_CONFIG_MII_SPEED;
+		if (state->pause & MLO_PAUSE_TX)
+			ctrl4 |= MVPP22_CTRL4_TX_FC_EN;
+		if (state->pause & MLO_PAUSE_RX)
+			ctrl4 |= MVPP22_CTRL4_RX_FC_EN;
+	} else if (phy_interface_mode_is_8023z(state->interface)) {
+		/* 1000BaseX and 2500BaseX ports cannot negotiate speed nor can
+		 * they negotiate duplex: they are always operating with a fixed
+		 * speed of 1000/2500Mbps in full duplex, so force 1000/2500
+		 * speed and full duplex here.
+		 */
+		ctrl0 |= MVPP2_GMAC_PORT_TYPE_MASK;
+		an &= ~(MVPP2_GMAC_FORCE_LINK_DOWN | MVPP2_GMAC_FORCE_LINK_PASS);
+		an |= MVPP2_GMAC_CONFIG_GMII_SPEED |
+		      MVPP2_GMAC_CONFIG_FULL_DUPLEX;
 
-		ctrl4 &= ~MVPP22_CTRL4_DP_CLK_SEL;
-		ctrl4 |= MVPP22_CTRL4_EXT_PIN_GMII_SEL |
-			 MVPP22_CTRL4_SYNC_BYPASS_DIS |
-			 MVPP22_CTRL4_QSGMII_BYPASS_ACTIVE;
+		if (state->pause & MLO_PAUSE_AN && state->an_enabled) {
+			an |= MVPP2_GMAC_FLOW_CTRL_AUTONEG;
+		} else {
+			if (state->pause & MLO_PAUSE_TX)
+				ctrl4 |= MVPP22_CTRL4_TX_FC_EN;
+			if (state->pause & MLO_PAUSE_RX)
+				ctrl4 |= MVPP22_CTRL4_RX_FC_EN;
+		}
 	}
 
 	writel(ctrl0, port->base + MVPP2_GMAC_CTRL_0_REG);
@@ -4685,8 +4711,7 @@ static void mvpp2_mac_link_up(struct net_device *dev, unsigned int mode,
 	    interface != PHY_INTERFACE_MODE_10GKR) {
 		val = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 		val &= ~MVPP2_GMAC_FORCE_LINK_DOWN;
-		if (phy_interface_mode_is_rgmii(interface))
-			val |= MVPP2_GMAC_FORCE_LINK_PASS;
+		val |= MVPP2_GMAC_FORCE_LINK_PASS;
 		writel(val, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 	}
 
-- 
2.7.4

[PATCH 2/5] net: marvell: mvpp2: fix stuck in-band SGMII negotiation

[Russell King]

It appears that the mvpp22 can get stuck with SGMII negotiation.  The
symptoms are that in-band negotiation never completes and the partner
(eg, PHY) never reports SGMII link up, or if it supports negotiation
bypass, goes into negotiation bypass mode (which will happen when the
PHY sees that the MAC is alive but gets no response.)

Triggering the PHY end of the link to re-negotiate results in the
bypass bit clearing on the PHY, and then re-setting - indicating that
the problem is at the mvpp22 GMAC end.

Asserting the GMAC reset and de-asserting it resolves the issue.
Arrange to assert the GMAC reset at probe time, and deassert it only
after we have configured the GMAC for the appropriate mode.  This
resolves the issue.

Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index c590dc7ba70a..1cb5023b2575 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -1392,13 +1392,9 @@ static void mvpp2_port_reset(struct mvpp2_port *port)
 	for (i = 0; i < ARRAY_SIZE(mvpp2_ethtool_regs); i++)
 		mvpp2_read_count(port, &mvpp2_ethtool_regs[i]);
 
-	val = readl(port->base + MVPP2_GMAC_CTRL_2_REG) &
-		    ~MVPP2_GMAC_PORT_RESET_MASK;
+	val = readl(port->base + MVPP2_GMAC_CTRL_2_REG) |
+	      MVPP2_GMAC_PORT_RESET_MASK;
 	writel(val, port->base + MVPP2_GMAC_CTRL_2_REG);
-
-	while (readl(port->base + MVPP2_GMAC_CTRL_2_REG) &
-	       MVPP2_GMAC_PORT_RESET_MASK)
-		continue;
 }
 
 /* Change maximum receive size of the port */
@@ -4554,12 +4550,15 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 			      const struct phylink_link_state *state)
 {
 	u32 an, ctrl0, ctrl2, ctrl4;
+	u32 old_ctrl2;
 
 	an = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 	ctrl0 = readl(port->base + MVPP2_GMAC_CTRL_0_REG);
 	ctrl2 = readl(port->base + MVPP2_GMAC_CTRL_2_REG);
 	ctrl4 = readl(port->base + MVPP22_GMAC_CTRL_4_REG);
 
+	old_ctrl2 = ctrl2;
+
 	/* Force link down */
 	an &= ~MVPP2_GMAC_FORCE_LINK_PASS;
 	an |= MVPP2_GMAC_FORCE_LINK_DOWN;
@@ -4656,6 +4655,12 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 	writel(ctrl2, port->base + MVPP2_GMAC_CTRL_2_REG);
 	writel(ctrl4, port->base + MVPP22_GMAC_CTRL_4_REG);
 	writel(an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+
+	if (old_ctrl2 & MVPP2_GMAC_PORT_RESET_MASK) {
+		while (readl(port->base + MVPP2_GMAC_CTRL_2_REG) &
+		       MVPP2_GMAC_PORT_RESET_MASK)
+			continue;
+	}
 }
 
 static void mvpp2_mac_config(struct net_device *dev, unsigned int mode,
-- 
2.7.4

[PATCH 3/5] net: marvell: mvpp2: only reprogram what is necessary on mac_config

[Russell King]

mac_config() can be called at any point, and the expected behaviour
from MAC drivers is to only reprogram when necessary - and certainly
avoid taking the link down on every call.

Unfortunately, mvpp2 does exactly that - it takes the link down, and
reprograms everything, and then releases the forced-link down.

This is bad, it can cause the link to bounce:

- SFP detects signal, disables LOS indication.
- SFP code calls into phylink, calling phylink_sfp_link_up() which
  triggers a resolve.
- phylink_resolve() calls phylink_get_mac_state() and finds the MAC
  reporting link up.
- phylink wants to configure the pause mode on the MAC, so calls
  phylink_mac_config()
- mvpp2 takes the link down temporarily, generating a MAC link down
  event followed by another MAC link event.
- phylink calls mac_link_up() and then processes the MAC link down
  event.
- phylink_resolve() gets called again, registers the link down, and
  calls mach_link_down() before re-running itself.
- phylink_resolve() starts again at step 3 above.  This sequence
  repeats.

GMAC versions prior to mvpp2 do not require the link to be taken down
except when certain link properties (eg, switching between SGMII and
1000base-X mode, or enabling/disabling in-band negotiation) are
changed.  Implement this for mvpp2.

Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 58 +++++++++++++++----------
 1 file changed, 35 insertions(+), 23 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 1cb5023b2575..624514bc1681 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -4549,29 +4549,21 @@ static void mvpp2_xlg_config(struct mvpp2_port *port, unsigned int mode,
 static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 			      const struct phylink_link_state *state)
 {
-	u32 an, ctrl0, ctrl2, ctrl4;
-	u32 old_ctrl2;
+	u32 old_an, an;
+	u32 old_ctrl0, ctrl0;
+	u32 old_ctrl2, ctrl2;
+	u32 old_ctrl4, ctrl4;
 
-	an = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
-	ctrl0 = readl(port->base + MVPP2_GMAC_CTRL_0_REG);
-	ctrl2 = readl(port->base + MVPP2_GMAC_CTRL_2_REG);
-	ctrl4 = readl(port->base + MVPP22_GMAC_CTRL_4_REG);
-
-	old_ctrl2 = ctrl2;
-
-	/* Force link down */
-	an &= ~MVPP2_GMAC_FORCE_LINK_PASS;
-	an |= MVPP2_GMAC_FORCE_LINK_DOWN;
-	writel(an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
-
-	/* Set the GMAC in a reset state */
-	ctrl2 |= MVPP2_GMAC_PORT_RESET_MASK;
-	writel(ctrl2, port->base + MVPP2_GMAC_CTRL_2_REG);
+	old_an = an = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	old_ctrl0 = ctrl0 = readl(port->base + MVPP2_GMAC_CTRL_0_REG);
+	old_ctrl2 = ctrl2 = readl(port->base + MVPP2_GMAC_CTRL_2_REG);
+	old_ctrl4 = ctrl4 = readl(port->base + MVPP22_GMAC_CTRL_4_REG);
 
 	an &= ~(MVPP2_GMAC_CONFIG_MII_SPEED | MVPP2_GMAC_CONFIG_GMII_SPEED |
 		MVPP2_GMAC_AN_SPEED_EN | MVPP2_GMAC_FC_ADV_EN |
 		MVPP2_GMAC_FC_ADV_ASM_EN | MVPP2_GMAC_FLOW_CTRL_AUTONEG |
-		MVPP2_GMAC_CONFIG_FULL_DUPLEX | MVPP2_GMAC_AN_DUPLEX_EN);
+		MVPP2_GMAC_CONFIG_FULL_DUPLEX | MVPP2_GMAC_AN_DUPLEX_EN |
+		MVPP2_GMAC_IN_BAND_AUTONEG | MVPP2_GMAC_IN_BAND_AUTONEG_BYPASS);
 	ctrl0 &= ~MVPP2_GMAC_PORT_TYPE_MASK;
 	ctrl2 &= ~(MVPP2_GMAC_INBAND_AN_MASK | MVPP2_GMAC_PORT_RESET_MASK |
 		   MVPP2_GMAC_PCS_ENABLE_MASK);
@@ -4638,7 +4630,8 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 		 */
 		ctrl0 |= MVPP2_GMAC_PORT_TYPE_MASK;
 		an &= ~(MVPP2_GMAC_FORCE_LINK_DOWN | MVPP2_GMAC_FORCE_LINK_PASS);
-		an |= MVPP2_GMAC_CONFIG_GMII_SPEED |
+		an |= MVPP2_GMAC_IN_BAND_AUTONEG |
+		      MVPP2_GMAC_CONFIG_GMII_SPEED |
 		      MVPP2_GMAC_CONFIG_FULL_DUPLEX;
 
 		if (state->pause & MLO_PAUSE_AN && state->an_enabled) {
@@ -4651,10 +4644,29 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
 		}
 	}
 
-	writel(ctrl0, port->base + MVPP2_GMAC_CTRL_0_REG);
-	writel(ctrl2, port->base + MVPP2_GMAC_CTRL_2_REG);
-	writel(ctrl4, port->base + MVPP22_GMAC_CTRL_4_REG);
-	writel(an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	if ((old_ctrl0 ^ ctrl0) & MVPP2_GMAC_PORT_TYPE_MASK ||
+	    (old_ctrl2 ^ ctrl2) & MVPP2_GMAC_INBAND_AN_MASK ||
+	    (old_an ^ an) & MVPP2_GMAC_IN_BAND_AUTONEG) {
+		/* Force link down */
+		old_an &= ~MVPP2_GMAC_FORCE_LINK_PASS;
+		old_an |= MVPP2_GMAC_FORCE_LINK_DOWN;
+		writel(old_an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+
+		/* Set the GMAC in a reset state - do this in a way that
+		 * ensures we clear it below.
+		 */
+		old_ctrl2 |= MVPP2_GMAC_PORT_RESET_MASK;
+		writel(old_ctrl2, port->base + MVPP2_GMAC_CTRL_2_REG);
+	}
+
+	if (old_ctrl0 != ctrl0)
+		writel(ctrl0, port->base + MVPP2_GMAC_CTRL_0_REG);
+	if (old_ctrl2 != ctrl2)
+		writel(ctrl2, port->base + MVPP2_GMAC_CTRL_2_REG);
+	if (old_ctrl4 != ctrl4)
+		writel(ctrl4, port->base + MVPP22_GMAC_CTRL_4_REG);
+	if (old_an != an)
+		writel(an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 
 	if (old_ctrl2 & MVPP2_GMAC_PORT_RESET_MASK) {
 		while (readl(port->base + MVPP2_GMAC_CTRL_2_REG) &
-- 
2.7.4

[PATCH 4/5] net: marvell: mvpp2: read correct pause bits

[Russell King]

When reading the pause bits in mac_link_state, mvpp2 was reporting
the state of the "active pause" bits, which are set when the MAC is
in pause mode.  This is not what phylink wants - we want the
negotiated pause state.  Fix the definition so we read the correct
bits.

Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index 398328f10743..96e3f0669032 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -402,8 +402,8 @@
 #define     MVPP2_GMAC_STATUS0_GMII_SPEED	BIT(1)
 #define     MVPP2_GMAC_STATUS0_MII_SPEED	BIT(2)
 #define     MVPP2_GMAC_STATUS0_FULL_DUPLEX	BIT(3)
-#define     MVPP2_GMAC_STATUS0_RX_PAUSE		BIT(6)
-#define     MVPP2_GMAC_STATUS0_TX_PAUSE		BIT(7)
+#define     MVPP2_GMAC_STATUS0_RX_PAUSE		BIT(4)
+#define     MVPP2_GMAC_STATUS0_TX_PAUSE		BIT(5)
 #define     MVPP2_GMAC_STATUS0_AN_COMPLETE	BIT(11)
 #define MVPP2_GMAC_PORT_FIFO_CFG_1_REG		0x1c
 #define     MVPP2_GMAC_TX_FIFO_MIN_TH_OFFS	6
-- 
2.7.4

[PATCH 5/5] net: marvell: mvpp2: fix AN restart

[Russell King]

phylink already limits which interface modes are able to call the
MACs AN restart function, but in any case, the commentry seems
incorrect: the AN restart bit does not automatically clear when
set.  This has been found via manual setting using devmem2, and
we can observe that the AN does indeed restart and complete, yet
the AN restart bit remains set.  Explicitly clear the AN restart
bit.

Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 624514bc1681..93fed4080dbf 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -4512,17 +4512,12 @@ static int mvpp2_phylink_mac_link_state(struct net_device *dev,
 static void mvpp2_mac_an_restart(struct net_device *dev)
 {
 	struct mvpp2_port *port = netdev_priv(dev);
-	u32 val;
-
-	if (port->phy_interface != PHY_INTERFACE_MODE_SGMII)
-		return;
+	u32 val = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 
-	val = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
-	/* The RESTART_AN bit is cleared by the h/w after restarting the AN
-	 * process.
-	 */
-	val |= MVPP2_GMAC_IN_BAND_RESTART_AN | MVPP2_GMAC_IN_BAND_AUTONEG;
-	writel(val, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	writel(val | MVPP2_GMAC_IN_BAND_RESTART_AN,
+	       port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	writel(val & ~MVPP2_GMAC_IN_BAND_RESTART_AN,
+	       port->base + MVPP2_GMAC_AUTONEG_CONFIG);
 }
 
 static void mvpp2_xlg_config(struct mvpp2_port *port, unsigned int mode,
-- 
2.7.4

Re: [PATCH net-next 0/5] mvpp2 phylink fixes

[David Miller]

From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Date: Fri, 8 Feb 2019 15:34:32 +0000

> Having spent a while debugging issues with Sven Auhagen, it appears
> that the mvpp2 network driver's phylink support isn't quite correct.
> 
> This series fixes that up, but, despite being tested locally, by
> Sven, and by Antoine, I would prefer it to be applied to net-next
> so that there is time for more people to test before it hits -rc or
> stable backports.
 ...

Series applied to net-next, thanks.