The integrated PCS supports 802.3z (BASE-X) modes when the Synopsys
IP is coupled with an appropriate SerDes to provide the electrical
interface. The PCS presents a TBI interface to the SerDes for this.
Thus, the BASE-X related registers are only present when TBI mode is
supported.

dwmac-qcom-ethqos added support for using 2.5G with the integrated PCS
by calling dwmac_ctrl_ane() directly.

Add support for the following to the integrated PCS:
- 1000BASE-X protocol unconditionally.
- 2500BASE-X if the coupled SerDes supports 2.5G speed.
- The above without autonegotiation.
- If the PCS supports TBI, then optional BASE-X autonegotiation for each
  of the above.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.c  | 96 ++++++++++++++++++-
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.h  |  1 +
 include/linux/stmmac.h                        |  1 +
 3 files changed, 95 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
index 88fa359ea716..e606dfb85f94 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
@@ -16,6 +16,27 @@
 #define GMAC_ANE_LPA	0x0c	/* ANE link partener ability */
 #define GMAC_TBI	0x14	/* TBI extend status */
 
+static unsigned int dwmac_integrated_pcs_inband_caps(struct phylink_pcs *pcs,
+						     phy_interface_t interface)
+{
+	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
+	unsigned int ib_caps;
+
+	if (phy_interface_mode_is_8023z(interface)) {
+		ib_caps = LINK_INBAND_DISABLE;
+
+		/* If the PCS supports TBI/RTBI, then BASE-X negotiation is
+		 * supported.
+		 */
+		if (spcs->support_tbi_rtbi)
+			ib_caps |= LINK_INBAND_ENABLE;
+
+		return ib_caps;
+	}
+
+	return 0;
+}
+
 static int dwmac_integrated_pcs_enable(struct phylink_pcs *pcs)
 {
 	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
@@ -36,7 +57,39 @@ static void dwmac_integrated_pcs_get_state(struct phylink_pcs *pcs,
 					   unsigned int neg_mode,
 					   struct phylink_link_state *state)
 {
-	state->link = false;
+	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
+	u32 status, lpa;
+
+	status = readl(spcs->base + GMAC_AN_STATUS);
+
+	if (phy_interface_mode_is_8023z(state->interface)) {
+		/* For BASE-X modes, the PCS block supports the advertisement
+		 * and link partner advertisement registers using standard
+		 * 802.3 format. The status register also has the link status
+		 * and AN complete bits in the same bit location. This will
+		 * only be used when AN is enabled.
+		 */
+		lpa = readl(spcs->base + GMAC_ANE_LPA);
+
+		phylink_mii_c22_pcs_decode_state(state, neg_mode, status, lpa);
+	} else {
+		state->link = false;
+	}
+}
+
+static int dwmac_integrated_pcs_config_aneg(struct stmmac_pcs *spcs,
+					    phy_interface_t interface,
+					    const unsigned long *advertising)
+{
+	bool changed = false;
+	u32 adv;
+
+	adv = phylink_mii_c22_pcs_encode_advertisement(interface, advertising);
+	if (readl(spcs->base + GMAC_ANE_ADV) != adv)
+		changed = true;
+	writel(adv, spcs->base + GMAC_ANE_ADV);
+
+	return changed;
 }
 
 static int dwmac_integrated_pcs_config(struct phylink_pcs *pcs,
@@ -46,13 +99,28 @@ static int dwmac_integrated_pcs_config(struct phylink_pcs *pcs,
 				       bool permit_pause_to_mac)
 {
 	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
+	bool changed = false, ane = true;
+
+	/* Only configure the advertisement and allow AN in BASE-X mode if
+	 * the core supports TBI/RTBI. AN will be filtered out by via phylink
+	 * and the .pcs_inband_caps() method above.
+	 */
+	if (phy_interface_mode_is_8023z(interface) &&
+	    spcs->support_tbi_rtbi) {
+		ane = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED;
+
+		changed = dwmac_integrated_pcs_config_aneg(spcs, interface,
+							   advertising);
+	}
 
-	dwmac_ctrl_ane(spcs->base, 0, 1, spcs->priv->hw->reverse_sgmii_enable);
+	dwmac_ctrl_ane(spcs->base, 0, ane,
+		       spcs->priv->hw->reverse_sgmii_enable);
 
-	return 0;
+	return changed;
 }
 
 static const struct phylink_pcs_ops dwmac_integrated_pcs_ops = {
+	.pcs_inband_caps = dwmac_integrated_pcs_inband_caps,
 	.pcs_enable = dwmac_integrated_pcs_enable,
 	.pcs_disable = dwmac_integrated_pcs_disable,
 	.pcs_get_state = dwmac_integrated_pcs_get_state,
@@ -84,9 +152,18 @@ void stmmac_integrated_pcs_irq(struct stmmac_priv *priv, u32 status,
 int stmmac_integrated_pcs_get_phy_intf_sel(struct phylink_pcs *pcs,
 					   phy_interface_t interface)
 {
+	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
+
 	if (interface == PHY_INTERFACE_MODE_SGMII)
 		return PHY_INTF_SEL_SGMII;
 
+	if (phy_interface_mode_is_8023z(interface)) {
+		if (spcs->support_tbi_rtbi)
+			return PHY_INTF_SEL_TBI;
+		else
+			return PHY_INTF_SEL_SGMII;
+	}
+
 	return -EINVAL;
 }
 
@@ -104,7 +181,20 @@ int stmmac_integrated_pcs_init(struct stmmac_priv *priv, unsigned int offset,
 	spcs->int_mask = int_mask;
 	spcs->pcs.ops = &dwmac_integrated_pcs_ops;
 
+	/* If the PCS supports extended status, then it supports BASE-X AN
+	 * with a TBI interface to the SerDes. Otherwise, we can support
+	 * BASE-X without AN using SGMII, which is required for qcom-ethqos.
+	 */
+	if (readl(spcs->base + GMAC_AN_STATUS) & BMSR_ESTATEN)
+		spcs->support_tbi_rtbi = true;
+
 	__set_bit(PHY_INTERFACE_MODE_SGMII, spcs->pcs.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_1000BASEX, spcs->pcs.supported_interfaces);
+
+	/* Only allow 2500BASE-X if the SerDes has support. */
+	if (priv->plat->flags & STMMAC_FLAG_SERDES_SUPPORTS_2500M)
+		__set_bit(PHY_INTERFACE_MODE_2500BASEX,
+			  spcs->pcs.supported_interfaces);
 
 	priv->integrated_pcs = spcs;
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index 23bbd4f10bf8..12ea87792fcb 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -32,6 +32,7 @@ struct stmmac_pcs {
 	void __iomem *base;
 	u32 int_mask;
 	struct phylink_pcs pcs;
+	bool support_tbi_rtbi;
 };
 
 static inline struct stmmac_pcs *
diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index b96ae9dadfab..aa57ee327606 100644
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -192,6 +192,7 @@ enum dwmac_core_type {
 #define STMMAC_FLAG_EN_TX_LPI_CLK_PHY_CAP	BIT(12)
 #define STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY	BIT(13)
 #define STMMAC_FLAG_KEEP_PREAMBLE_BEFORE_SFD	BIT(14)
+#define STMMAC_FLAG_SERDES_SUPPORTS_2500M	BIT(15)
 
 struct mac_device_info;
 
-- 
2.47.3

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index cb1c074c2053..f4b63544895e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -828,6 +828,7 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 	if (ethqos->serdes_phy) {
 		plat_dat->serdes_powerup = qcom_ethqos_serdes_powerup;
 		plat_dat->serdes_powerdown  = qcom_ethqos_serdes_powerdown;
+		plat_dat->flags |= STMMAC_FLAG_SERDES_SUPPORTS_2500M;
 	}
 
 	/* Enable TSO on queue0 and enable TBS on rest of the queues */
-- 
2.47.3

dwmac-qcom-ethqos supports SGMII and 2500BASE-X using the integrated
PCS, so we need to expand the PCS support to include support for
BASE-X modes.

Add support to the prereset configuration to detect 2500BASE-X, and
arrange for stmmac_mac_select_pcs() to return the integrated PCS if
its supported_interfaces bitmap reports support for the interface mode.

This results in priv->hw->pcs now being write-only, so remove it.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/common.h      | 4 ----
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 ++------
 2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index d26e8a063022..6492af5f8a06 100644
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -277,9 +277,6 @@ struct stmmac_safety_stats {
 #define FLOW_TX		2
 #define FLOW_AUTO	(FLOW_TX | FLOW_RX)
 
-/* PCS defines */
-#define STMMAC_PCS_SGMII	(1 << 1)
-
 #define SF_DMA_MODE 1		/* DMA STORE-AND-FORWARD Operation Mode */
 
 /* DMA HW feature register fields */
@@ -634,7 +631,6 @@ struct mac_device_info {
 	unsigned int unicast_filter_entries;
 	unsigned int mcast_bits_log2;
 	unsigned int rx_csum;
-	unsigned int pcs;
 	unsigned int xlgmac;
 	unsigned int num_vlan;
 	u32 vlan_filter[32];
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index d7c730179a7f..1eeae680d777 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -953,11 +953,8 @@ static struct phylink_pcs *stmmac_mac_select_pcs(struct phylink_config *config,
 			return pcs;
 	}
 
-	/* The PCS control register is only relevant for SGMII, TBI and RTBI
-	 * modes. We no longer support TBI or RTBI, so only configure this
-	 * register when operating in SGMII mode with the integrated PCS.
-	 */
-	if (priv->hw->pcs & STMMAC_PCS_SGMII && priv->integrated_pcs)
+	if (priv->integrated_pcs &&
+	    test_bit(interface, priv->integrated_pcs->pcs.supported_interfaces))
 		return &priv->integrated_pcs->pcs;
 
 	return NULL;
@@ -1215,7 +1212,6 @@ static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
 
 	if (priv->dma_cap.pcs && interface == PHY_INTERFACE_MODE_SGMII) {
 		netdev_dbg(priv->dev, "PCS SGMII support enabled\n");
-		priv->hw->pcs = STMMAC_PCS_SGMII;
 
 		switch (speed) {
 		case SPEED_10:
-- 
2.47.3

We need to describe one more register (offset and field bitmask) to
the PCS code. Move the existing PCS offset and interrupt enable bits
to a new struct and pass that in to stmmac_integrated_pcs_init().

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c | 9 ++++++---
 drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c    | 8 ++++++--
 drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c     | 8 ++++----
 drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h     | 9 +++++++--
 4 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
index af566636fad9..a3ef237de1b8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
@@ -22,14 +22,17 @@
 #include "stmmac_ptp.h"
 #include "dwmac1000.h"
 
+static const struct stmmac_pcs_info dwmac1000_pcs_info = {
+	.pcs_offset = GMAC_PCS_BASE,
+	.int_mask = GMAC_INT_DISABLE_PCSLINK | GMAC_INT_DISABLE_PCSAN,
+};
+
 static int dwmac1000_pcs_init(struct stmmac_priv *priv)
 {
 	if (!priv->dma_cap.pcs)
 		return 0;
 
-	return stmmac_integrated_pcs_init(priv, GMAC_PCS_BASE,
-					  GMAC_INT_DISABLE_PCSLINK |
-					  GMAC_INT_DISABLE_PCSAN);
+	return stmmac_integrated_pcs_init(priv, &dwmac1000_pcs_info);
 }
 
 static void dwmac1000_core_init(struct mac_device_info *hw,
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index 623868afe93d..7f4949229288 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -22,13 +22,17 @@
 #include "dwmac4.h"
 #include "dwmac5.h"
 
+static const struct stmmac_pcs_info dwmac4_pcs_info = {
+	.pcs_offset = GMAC_PCS_BASE,
+	.int_mask = GMAC_INT_PCS_LINK | GMAC_INT_PCS_ANE,
+};
+
 static int dwmac4_pcs_init(struct stmmac_priv *priv)
 {
 	if (!priv->dma_cap.pcs)
 		return 0;
 
-	return stmmac_integrated_pcs_init(priv, GMAC_PCS_BASE,
-					  GMAC_INT_PCS_LINK | GMAC_INT_PCS_ANE);
+	return stmmac_integrated_pcs_init(priv, &dwmac4_pcs_info);
 }
 
 static void dwmac4_core_init(struct mac_device_info *hw,
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
index e606dfb85f94..77a83e415597 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
@@ -167,8 +167,8 @@ int stmmac_integrated_pcs_get_phy_intf_sel(struct phylink_pcs *pcs,
 	return -EINVAL;
 }
 
-int stmmac_integrated_pcs_init(struct stmmac_priv *priv, unsigned int offset,
-			       u32 int_mask)
+int stmmac_integrated_pcs_init(struct stmmac_priv *priv,
+			       const struct stmmac_pcs_info *pcs_info)
 {
 	struct stmmac_pcs *spcs;
 
@@ -177,8 +177,8 @@ int stmmac_integrated_pcs_init(struct stmmac_priv *priv, unsigned int offset,
 		return -ENOMEM;
 
 	spcs->priv = priv;
-	spcs->base = priv->ioaddr + offset;
-	spcs->int_mask = int_mask;
+	spcs->base = priv->ioaddr + pcs_info->pcs_offset;
+	spcs->int_mask = pcs_info->int_mask;
 	spcs->pcs.ops = &dwmac_integrated_pcs_ops;
 
 	/* If the PCS supports extended status, then it supports BASE-X AN
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index 12ea87792fcb..f3dada71e381 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -27,6 +27,11 @@
 
 struct stmmac_priv;
 
+struct stmmac_pcs_info {
+	unsigned int pcs_offset;
+	u32 int_mask;
+};
+
 struct stmmac_pcs {
 	struct stmmac_priv *priv;
 	void __iomem *base;
@@ -45,8 +50,8 @@ void stmmac_integrated_pcs_irq(struct stmmac_priv *priv, u32 status,
 			       struct stmmac_extra_stats *x);
 int stmmac_integrated_pcs_get_phy_intf_sel(struct phylink_pcs *pcs,
 					   phy_interface_t interface);
-int stmmac_integrated_pcs_init(struct stmmac_priv *priv, unsigned int offset,
-			       u32 int_mask);
+int stmmac_integrated_pcs_init(struct stmmac_priv *priv,
+			       const struct stmmac_pcs_info *pcs_info);
 
 /**
  * dwmac_ctrl_ane - To program the AN Control Register.
-- 
2.47.3

Report the link, speed and duplex for SGMII links, read from the
SGMII, RGMII and SMII status and control register.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
rfc->v1: fix setting SGMII's link status - depend on both link status.
v2:
 - fill in rsgmii offset and status fields in dwmac cores
 - rename new GMAC_RGSMIII_xxx constants to GMAC_RGSMII_xxx
---
 .../net/ethernet/stmicro/stmmac/dwmac1000.h   | 12 +----
 .../ethernet/stmicro/stmmac/dwmac1000_core.c  |  2 +
 drivers/net/ethernet/stmicro/stmmac/dwmac4.h  | 10 +---
 .../net/ethernet/stmicro/stmmac/dwmac4_core.c |  2 +
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.c  | 46 ++++++++++++++++++-
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.h  |  4 ++
 6 files changed, 54 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
index 9fe639fb06bb..1de1f929d61c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
@@ -70,18 +70,8 @@ enum power_event {
 #define GMAC_RGSMIIIS		0x000000d8	/* RGMII/SMII status */
 
 /* SGMII/RGMII status register */
-#define GMAC_RGSMIIIS_LNKMODE		BIT(0)
-#define GMAC_RGSMIIIS_SPEED		GENMASK(2, 1)
-#define GMAC_RGSMIIIS_LNKSTS		BIT(3)
-#define GMAC_RGSMIIIS_JABTO		BIT(4)
-#define GMAC_RGSMIIIS_FALSECARDET	BIT(5)
+#define GMAC_RSGMIIIS_MASK		GENMASK(15, 0)
 #define GMAC_RGSMIIIS_SMIDRXS		BIT(16)
-/* LNKMOD */
-#define GMAC_RGSMIIIS_LNKMOD_MASK	0x1
-/* LNKSPEED */
-#define GMAC_RGSMIIIS_SPEED_125		0x2
-#define GMAC_RGSMIIIS_SPEED_25		0x1
-#define GMAC_RGSMIIIS_SPEED_2_5		0x0
 
 /* GMAC Configuration defines */
 #define GMAC_CONTROL_2K 0x08000000	/* IEEE 802.3as 2K packets */
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
index a3ef237de1b8..31f6ac5432f2 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
@@ -24,6 +24,8 @@
 
 static const struct stmmac_pcs_info dwmac1000_pcs_info = {
 	.pcs_offset = GMAC_PCS_BASE,
+	.rgsmii_offset = GMAC_RGSMIIIS,
+	.rgsmii_status_mask = GMAC_RSGMIIIS_MASK,
 	.int_mask = GMAC_INT_DISABLE_PCSLINK | GMAC_INT_DISABLE_PCSAN,
 };
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
index d797d936aee1..ffcd036d4c02 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
@@ -470,15 +470,7 @@ static inline u32 mtl_low_credx_base_addr(const struct dwmac4_addrs *addrs,
 #define GMAC_PHYIF_CTRLSTATUS_TC		BIT(0)
 #define GMAC_PHYIF_CTRLSTATUS_LUD		BIT(1)
 #define GMAC_PHYIF_CTRLSTATUS_SMIDRXS		BIT(4)
-#define GMAC_PHYIF_CTRLSTATUS_LNKMOD		BIT(16)
-#define GMAC_PHYIF_CTRLSTATUS_SPEED		GENMASK(18, 17)
-#define GMAC_PHYIF_CTRLSTATUS_LNKSTS		BIT(19)
-#define GMAC_PHYIF_CTRLSTATUS_JABTO		BIT(20)
-#define GMAC_PHYIF_CTRLSTATUS_FALSECARDET	BIT(21)
-/* LNKSPEED */
-#define GMAC_PHYIF_CTRLSTATUS_SPEED_125		0x2
-#define GMAC_PHYIF_CTRLSTATUS_SPEED_25		0x1
-#define GMAC_PHYIF_CTRLSTATUS_SPEED_2_5		0x0
+#define GMAC_PHYIF_CTRLSTATUS_RSGMII_MASK	GENMASK(31, 16)
 
 extern const struct stmmac_dma_ops dwmac4_dma_ops;
 extern const struct stmmac_dma_ops dwmac410_dma_ops;
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index 7f4949229288..ced2cd98cc54 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -24,6 +24,8 @@
 
 static const struct stmmac_pcs_info dwmac4_pcs_info = {
 	.pcs_offset = GMAC_PCS_BASE,
+	.rgsmii_offset = GMAC_PHYIF_CONTROL_STATUS,
+	.rgsmii_status_mask = GMAC_PHYIF_CTRLSTATUS_RSGMII_MASK,
 	.int_mask = GMAC_INT_PCS_LINK | GMAC_INT_PCS_ANE,
 };
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
index 77a83e415597..ba0cf51e67f7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
@@ -16,6 +16,16 @@
 #define GMAC_ANE_LPA	0x0c	/* ANE link partener ability */
 #define GMAC_TBI	0x14	/* TBI extend status */
 
+/*
+ * RGSMII status bitfield definitions.
+ */
+#define GMAC_RGSMII_LNKMOD		BIT(0)
+#define GMAC_RGSMII_SPEED_MASK		GENMASK(2, 1)
+#define GMAC_RGSMII_SPEED_125		2
+#define GMAC_RGSMII_SPEED_25		1
+#define GMAC_RGSMII_SPEED_2_5		0
+#define GMAC_RGSMII_LNKSTS		BIT(3)
+
 static unsigned int dwmac_integrated_pcs_inband_caps(struct phylink_pcs *pcs,
 						     phy_interface_t interface)
 {
@@ -58,7 +68,7 @@ static void dwmac_integrated_pcs_get_state(struct phylink_pcs *pcs,
 					   struct phylink_link_state *state)
 {
 	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
-	u32 status, lpa;
+	u32 status, lpa, rgsmii;
 
 	status = readl(spcs->base + GMAC_AN_STATUS);
 
@@ -73,7 +83,37 @@ static void dwmac_integrated_pcs_get_state(struct phylink_pcs *pcs,
 
 		phylink_mii_c22_pcs_decode_state(state, neg_mode, status, lpa);
 	} else {
-		state->link = false;
+		rgsmii = field_get(spcs->rgsmii_status_mask,
+				   readl(spcs->rgsmii));
+
+		state->link = status & BMSR_LSTATUS &&
+			      rgsmii & GMAC_RGSMII_LNKSTS;
+
+		if (state->link && neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED) {
+			/* FIXME: fill in speed and duplex. This requires the
+			 * contents of the dwmac1000 GMAC_RGSMIIS or dwmac4
+			 * GMAC_PHYIF_CONTROL_STATUS register.
+			 */
+			state->duplex = rgsmii & GMAC_RGSMII_LNKMOD ?
+					DUPLEX_FULL : DUPLEX_HALF;
+			switch (FIELD_GET(GMAC_RGSMII_SPEED_MASK, rgsmii)) {
+			case GMAC_RGSMII_SPEED_2_5:
+				state->speed = SPEED_10;
+				break;
+
+			case GMAC_RGSMII_SPEED_25:
+				state->speed = SPEED_100;
+				break;
+
+			case GMAC_RGSMII_SPEED_125:
+				state->speed = SPEED_1000;
+				break;
+
+			default:
+				state->link = false;
+				break;
+			}
+		}
 	}
 }
 
@@ -178,6 +218,8 @@ int stmmac_integrated_pcs_init(struct stmmac_priv *priv,
 
 	spcs->priv = priv;
 	spcs->base = priv->ioaddr + pcs_info->pcs_offset;
+	spcs->rgsmii = priv->ioaddr + pcs_info->rgsmii_offset;
+	spcs->rgsmii_status_mask = pcs_info->rgsmii_status_mask;
 	spcs->int_mask = pcs_info->int_mask;
 	spcs->pcs.ops = &dwmac_integrated_pcs_ops;
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index f3dada71e381..b2b12d34b3dd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -29,12 +29,16 @@ struct stmmac_priv;
 
 struct stmmac_pcs_info {
 	unsigned int pcs_offset;
+	unsigned int rgsmii_offset;
+	u32 rgsmii_status_mask;
 	u32 int_mask;
 };
 
 struct stmmac_pcs {
 	struct stmmac_priv *priv;
 	void __iomem *base;
+	void __iomem *rgsmii;
+	u32 rgsmii_status_mask;
 	u32 int_mask;
 	struct phylink_pcs pcs;
 	bool support_tbi_rtbi;
-- 
2.47.3

Provide phylink with the integrated PCS autonegotiation capabilities,
and configure the PCS's AN settings according to phylink's requested
requirements.

This may cause regressions.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.c  | 24 +++++++++++++------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
index ba0cf51e67f7..0f9616fad4ef 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.c
@@ -32,6 +32,9 @@ static unsigned int dwmac_integrated_pcs_inband_caps(struct phylink_pcs *pcs,
 	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
 	unsigned int ib_caps;
 
+	if (interface == PHY_INTERFACE_MODE_SGMII)
+		return LINK_INBAND_ENABLE | LINK_INBAND_DISABLE;
+
 	if (phy_interface_mode_is_8023z(interface)) {
 		ib_caps = LINK_INBAND_DISABLE;
 
@@ -139,22 +142,29 @@ static int dwmac_integrated_pcs_config(struct phylink_pcs *pcs,
 				       bool permit_pause_to_mac)
 {
 	struct stmmac_pcs *spcs = phylink_pcs_to_stmmac_pcs(pcs);
-	bool changed = false, ane = true;
+	void __iomem *an_control = spcs->base + GMAC_AN_CTRL(0);
+	bool ane, changed = false;
+	u32 ctrl;
+
+	ane = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED;
 
 	/* Only configure the advertisement and allow AN in BASE-X mode if
 	 * the core supports TBI/RTBI. AN will be filtered out by via phylink
 	 * and the .pcs_inband_caps() method above.
 	 */
 	if (phy_interface_mode_is_8023z(interface) &&
-	    spcs->support_tbi_rtbi) {
-		ane = neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED;
-
+	    spcs->support_tbi_rtbi)
 		changed = dwmac_integrated_pcs_config_aneg(spcs, interface,
 							   advertising);
-	}
 
-	dwmac_ctrl_ane(spcs->base, 0, ane,
-		       spcs->priv->hw->reverse_sgmii_enable);
+	ctrl = readl(an_control) & ~(GMAC_AN_CTRL_ANE | GMAC_AN_CTRL_SGMRAL);
+	if (spcs->priv->hw->reverse_sgmii_enable)
+		ctrl |= GMAC_AN_CTRL_SGMRAL | GMAC_AN_CTRL_ANE;
+	else if (ane)
+		ctrl |= GMAC_AN_CTRL_ANE;
+	else
+		ctrl |= GMAC_AN_CTRL_SGMRAL;
+	writel(ctrl, an_control);
 
 	return changed;
 }
-- 
2.47.3

Report if/when qcom-ethqos changes the PCS configuration. With phylink
now setting the PCS configuration, there should be no need for drivers
to change this.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index b2b12d34b3dd..83651292578c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -71,6 +71,7 @@ static inline void dwmac_ctrl_ane(void __iomem *ioaddr, u32 reg, bool ane,
 				  bool srgmi_ral)
 {
 	u32 value = readl(ioaddr + GMAC_AN_CTRL(reg));
+	u32 old = value, diff;
 
 	/* Enable and restart the Auto-Negotiation */
 	if (ane)
@@ -84,6 +85,20 @@ static inline void dwmac_ctrl_ane(void __iomem *ioaddr, u32 reg, bool ane,
 	if (srgmi_ral)
 		value |= GMAC_AN_CTRL_SGMRAL;
 
+	diff = old ^ value;
+	if (diff & ~GMAC_AN_CTRL_RAN) {
+		pr_warn("dwmac: PCS configuration changed from phylink by glue, please report: 0x%08x -> 0x%08x\n",
+			old & ~GMAC_AN_CTRL_RAN, value & ~GMAC_AN_CTRL_RAN);
+#define REPORT_BIT(x) \
+		if (diff & GMAC_AN_CTRL_##x) \
+			pr_warn("dwmac: %8s %u -> %u\n", #x, \
+				!!(old & GMAC_AN_CTRL_##x), \
+				!!(value & GMAC_AN_CTRL_##x))
+		REPORT_BIT(ANE);
+		REPORT_BIT(SGMRAL);
+#undef REPORT_BIT
+	}
+
 	writel(value, ioaddr + GMAC_AN_CTRL(reg));
 }
 #endif /* __STMMAC_PCS_H__ */
-- 
2.47.3