Merge branch 'altera-tse-phylink'

Maxime Chevallier says:

====================
net: altera: tse: phylink conversion

This is V4 of a series converting the Altera TSE driver to phylink,
introducing a new PCS driver along the way.

The Altera TSE can be built with a SGMII/1000BaseX PCS, allowing to use
SFP ports with this MAC, which is the end goal of adding phylink support
and a proper PCS driver.

The PCS itself can either be mapped in the MAC's register space, in that
case, it's accessed through 32 bits registers, with the higher 16 bits
always 0. Alternatively, it can sit on its own register space, exposing
16 bits registers, some of which ressemble the standard PHY registers.

To tackle that rework, several things needs updating, starting by the DT
binding, since we add support for a new register range for the PCS.

Hence, the first patch of the series is a conversion to YAML of the
existing binding.

Then, patch 2 does a bit of simple cleanup to the TSE driver, using nice
reverse xmas tree definitions.

Patch 3 adds the actual PCS driver, as a standalone driver. Some future
series will then reuse that PCS driver from the dwmac-socfpga driver,
which implements support for this exact PCS too, allowing to share the
code nicely.

Patch 4 is then a phylink conversion of the altera_tse driver, to use
this new PCS driver.

Finally, patch 5 updates the newly converted DT binding to support the
pcs register range.

This series contains bits and pieces for this conversion, please tell me if
you want me to send it as individual patches.

V4 Changes:
 - Add missing MODULE_* macros to the TSE PCS driver

V3 Changes:
 - YAML binding conversion changes and PCS addition changes thanks to
   Krzysztof's reviews

V2 Changes :
 - Fixed the binding after the YAML conversion
 - Added a pcs_validate() callback
 - Introduced a comment to justify a soft reset for the PCS
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/altera_tse.txt

-* Altera Triple-Speed Ethernet MAC driver (TSE)
-
-Required properties:
-- compatible: Should be "altr,tse-1.0" for legacy SGDMA based TSE, and should
-		be "altr,tse-msgdma-1.0" for the preferred MSGDMA based TSE.
-		ALTR is supported for legacy device trees, but is deprecated.
-		altr should be used for all new designs.
-- reg: Address and length of the register set for the device. It contains
-  the information of registers in the same order as described by reg-names
-- reg-names: Should contain the reg names
-  "control_port": MAC configuration space region
-  "tx_csr":       xDMA Tx dispatcher control and status space region
-  "tx_desc":      MSGDMA Tx dispatcher descriptor space region
-  "rx_csr" :      xDMA Rx dispatcher control and status space region
-  "rx_desc":      MSGDMA Rx dispatcher descriptor space region
-  "rx_resp":      MSGDMA Rx dispatcher response space region
-  "s1":		  SGDMA descriptor memory
-- interrupts: Should contain the TSE interrupts and its mode.
-- interrupt-names: Should contain the interrupt names
-  "rx_irq":       xDMA Rx dispatcher interrupt
-  "tx_irq":       xDMA Tx dispatcher interrupt
-- rx-fifo-depth: MAC receive FIFO buffer depth in bytes
-- tx-fifo-depth: MAC transmit FIFO buffer depth in bytes
-- phy-mode: See ethernet.txt in the same directory.
-- phy-handle: See ethernet.txt in the same directory.
-- phy-addr: See ethernet.txt in the same directory. A configuration should
-		include phy-handle or phy-addr.
-- altr,has-supplementary-unicast:
-		If present, TSE supports additional unicast addresses.
-		Otherwise additional unicast addresses are not supported.
-- altr,has-hash-multicast-filter:
-		If present, TSE supports a hash based multicast filter.
-		Otherwise, hash-based multicast filtering is not supported.
-
-- mdio device tree subnode: When the TSE has a phy connected to its local
-		mdio, there must be device tree subnode with the following
-		required properties:
-
-	- compatible: Must be "altr,tse-mdio".
-	- #address-cells: Must be <1>.
-	- #size-cells: Must be <0>.
-
-	For each phy on the mdio bus, there must be a node with the following
-	fields:
-
-	- reg: phy id used to communicate to phy.
-	- device_type: Must be "ethernet-phy".
-
-The MAC address will be determined using the optional properties defined in
-ethernet.txt.
-
-Example:
-
-	tse_sub_0_eth_tse_0: ethernet@1,00000000 {
-		compatible = "altr,tse-msgdma-1.0";
-		reg =	<0x00000001 0x00000000 0x00000400>,
-			<0x00000001 0x00000460 0x00000020>,
-			<0x00000001 0x00000480 0x00000020>,
-			<0x00000001 0x000004A0 0x00000008>,
-			<0x00000001 0x00000400 0x00000020>,
-			<0x00000001 0x00000420 0x00000020>;
-		reg-names = "control_port", "rx_csr", "rx_desc", "rx_resp", "tx_csr", "tx_desc";
-		interrupt-parent = <&hps_0_arm_gic_0>;
-		interrupts = <0 41 4>, <0 40 4>;
-		interrupt-names = "rx_irq", "tx_irq";
-		rx-fifo-depth = <2048>;
-		tx-fifo-depth = <2048>;
-		address-bits = <48>;
-		max-frame-size = <1500>;
-		local-mac-address = [ 00 00 00 00 00 00 ];
-		phy-mode = "gmii";
-		altr,has-supplementary-unicast;
-		altr,has-hash-multicast-filter;
-		phy-handle = <&phy0>;
-		mdio {
-			compatible = "altr,tse-mdio";
-			#address-cells = <1>;
-			#size-cells = <0>;
-			phy0: ethernet-phy@0 {
-				reg = <0x0>;
-				device_type = "ethernet-phy";
-			};
-
-			phy1: ethernet-phy@1 {
-				reg = <0x1>;
-				device_type = "ethernet-phy";
-			};
-
-		};
-	};
-
-	tse_sub_1_eth_tse_0: ethernet@1,00001000 {
-		compatible = "altr,tse-msgdma-1.0";
-		reg = 	<0x00000001 0x00001000 0x00000400>,
-			<0x00000001 0x00001460 0x00000020>,
-			<0x00000001 0x00001480 0x00000020>,
-			<0x00000001 0x000014A0 0x00000008>,
-			<0x00000001 0x00001400 0x00000020>,
-			<0x00000001 0x00001420 0x00000020>;
-		reg-names = "control_port", "rx_csr", "rx_desc", "rx_resp", "tx_csr", "tx_desc";
-		interrupt-parent = <&hps_0_arm_gic_0>;
-		interrupts = <0 43 4>, <0 42 4>;
-		interrupt-names = "rx_irq", "tx_irq";
-		rx-fifo-depth = <2048>;
-		tx-fifo-depth = <2048>;
-		address-bits = <48>;
-		max-frame-size = <1500>;
-		local-mac-address = [ 00 00 00 00 00 00 ];
-		phy-mode = "gmii";
-		altr,has-supplementary-unicast;
-		altr,has-hash-multicast-filter;
-		phy-handle = <&phy1>;
-	};

Documentation/devicetree/bindings/net/altr,tse.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/altr,tse.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Altera Triple Speed Ethernet MAC driver (TSE)
+
+maintainers:
+  - Maxime Chevallier <maxime.chevallier@bootlin.com>
+
+properties:
+  compatible:
+    oneOf:
+      - const: altr,tse-1.0
+      - const: ALTR,tse-1.0
+        deprecated: true
+      - const: altr,tse-msgdma-1.0
+
+  interrupts:
+    minItems: 2
+
+  interrupt-names:
+    items:
+      - const: rx_irq
+      - const: tx_irq
+
+  rx-fifo-depth:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Depth in bytes of the RX FIFO
+
+  tx-fifo-depth:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Depth in bytes of the TX FIFO
+
+  altr,has-supplementary-unicast:
+    type: boolean
+    description:
+      If present, TSE supports additional unicast addresses.
+
+  altr,has-hash-multicast-filter:
+    type: boolean
+    description:
+      If present, TSE supports hash based multicast filter.
+
+  mdio:
+    $ref: mdio.yaml#
+    unevaluatedProperties: false
+    description:
+      Creates and registers an MDIO bus.
+
+    properties:
+      compatible:
+        const: altr,tse-mdio
+
+    required:
+      - compatible
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - rx-fifo-depth
+  - tx-fifo-depth
+
+allOf:
+  - $ref: "ethernet-controller.yaml#"
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - const: altr,tse-1.0
+              - const: ALTR,tse-1.0
+    then:
+      properties:
+        reg:
+          minItems: 4
+        reg-names:
+          items:
+            - const: control_port
+            - const: rx_csr
+            - const: tx_csr
+            - const: s1
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - altr,tse-msgdma-1.0
+    then:
+      properties:
+        reg:
+          minItems: 6
+          maxItems: 7
+        reg-names:
+          minItems: 6
+          items:
+            - const: control_port
+            - const: rx_csr
+            - const: rx_desc
+            - const: rx_resp
+            - const: tx_csr
+            - const: tx_desc
+            - const: pcs
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    tse_sub_0: ethernet@c0100000 {
+        compatible = "altr,tse-msgdma-1.0";
+        reg = <0xc0100000 0x00000400>,
+              <0xc0101000 0x00000020>,
+              <0xc0102000 0x00000020>,
+              <0xc0103000 0x00000008>,
+              <0xc0104000 0x00000020>,
+              <0xc0105000 0x00000020>,
+              <0xc0106000 0x00000100>;
+        reg-names = "control_port", "rx_csr", "rx_desc", "rx_resp", "tx_csr", "tx_desc", "pcs";
+        interrupt-parent = <&intc>;
+        interrupts = <0 44 4>,<0 45 4>;
+        interrupt-names = "rx_irq","tx_irq";
+        rx-fifo-depth = <2048>;
+        tx-fifo-depth = <2048>;
+        max-frame-size = <1500>;
+        local-mac-address = [ 00 00 00 00 00 00 ];
+        altr,has-supplementary-unicast;
+        altr,has-hash-multicast-filter;
+        sfp = <&sfp0>;
+        phy-mode = "sgmii";
+        managed = "in-band-status";
+    };
+  - |
+    tse_sub_1_eth_tse_0: ethernet@1,00001000 {
+        compatible = "altr,tse-msgdma-1.0";
+        reg = <0x00001000 0x00000400>,
+              <0x00001460 0x00000020>,
+              <0x00001480 0x00000020>,
+              <0x000014A0 0x00000008>,
+              <0x00001400 0x00000020>,
+              <0x00001420 0x00000020>;
+        reg-names = "control_port", "rx_csr", "rx_desc", "rx_resp", "tx_csr", "tx_desc";
+        interrupt-parent = <&hps_0_arm_gic_0>;
+        interrupts = <0 43 4>, <0 42 4>;
+        interrupt-names = "rx_irq", "tx_irq";
+        rx-fifo-depth = <2048>;
+        tx-fifo-depth = <2048>;
+        max-frame-size = <1500>;
+        local-mac-address = [ 00 00 00 00 00 00 ];
+        phy-mode = "gmii";
+        altr,has-supplementary-unicast;
+        altr,has-hash-multicast-filter;
+        phy-handle = <&phy1>;
+        mdio {
+            compatible = "altr,tse-mdio";
+            #address-cells = <1>;
+            #size-cells = <0>;
+            phy1: ethernet-phy@1 {
+                reg = <0x1>;
+            };
+        };
+    };
+
+...

MAINTAINERS

@@ -878,6 +878,13 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/net/ethernet/altera/
 
+ALTERA TSE PCS
+M:	Maxime Chevallier <maxime.chevallier@bootlin.com>
+L:	netdev@vger.kernel.org
+S:	Supported
+F:	drivers/net/pcs/pcs-altera-tse.c
+F:	include/linux/pcs-altera-tse.h
+
 ALTERA UART/JTAG UART SERIAL DRIVERS
 M:	Tobias Klauser <tklauser@distanz.ch>
 L:	linux-serial@vger.kernel.org

drivers/net/ethernet/altera/Kconfig

@@ -3,6 +3,8 @@ config ALTERA_TSE
 	tristate "Altera Triple-Speed Ethernet MAC support"
 	depends on HAS_DMA
 	select PHYLIB
+	select PHYLINK
+	select PCS_ALTERA_TSE
 	help
 	  This driver supports the Altera Triple-Speed (TSE) Ethernet MAC.
 

drivers/net/ethernet/altera/altera_tse.h

@@ -27,6 +27,7 @@
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/phy.h>
+#include <linux/phylink.h>
 
 #define ALTERA_TSE_SW_RESET_WATCHDOG_CNTR	10000
 #define ALTERA_TSE_MAC_FIFO_WIDTH		4	/* TX/RX FIFO width in
@@ -109,17 +110,6 @@
 #define MAC_CMDCFG_DISABLE_READ_TIMEOUT_GET(v)	GET_BIT_VALUE(v, 27)
 #define MAC_CMDCFG_CNT_RESET_GET(v)		GET_BIT_VALUE(v, 31)
 
-/* SGMII PCS register addresses
- */
-#define SGMII_PCS_SCRATCH	0x10
-#define SGMII_PCS_REV		0x11
-#define SGMII_PCS_LINK_TIMER_0	0x12
-#define SGMII_PCS_LINK_TIMER_1	0x13
-#define SGMII_PCS_IF_MODE	0x14
-#define SGMII_PCS_DIS_READ_TO	0x15
-#define SGMII_PCS_READ_TO	0x16
-#define SGMII_PCS_SW_RESET_TIMEOUT 100 /* usecs */
-
 /* MDIO registers within MAC register Space
  */
 struct altera_tse_mdio {
@@ -423,6 +413,9 @@ struct altera_tse_private {
 	void __iomem *tx_dma_csr;
 	void __iomem *tx_dma_desc;
 
+	/* SGMII PCS address space */
+	void __iomem *pcs_base;
+
 	/* Rx buffers queue */
 	struct tse_buffer *rx_ring;
 	u32 rx_cons;
@@ -480,6 +473,10 @@ struct altera_tse_private {
 	u32 msg_enable;
 
 	struct altera_dmaops *dmaops;
+
+	struct phylink *phylink;
+	struct phylink_config phylink_config;
+	struct phylink_pcs *pcs;
 };
 
 /* Function prototypes

drivers/net/ethernet/altera/altera_tse_ethtool.c

@@ -199,9 +199,9 @@ static int tse_reglen(struct net_device *dev)
 static void tse_get_regs(struct net_device *dev, struct ethtool_regs *regs,
 			 void *regbuf)
 {
-	int i;
 	struct altera_tse_private *priv = netdev_priv(dev);
 	u32 *buf = regbuf;
+	int i;
 
 	/* Set version to a known value, so ethtool knows
 	 * how to do any special formatting of this data.
@@ -221,6 +221,22 @@ static void tse_get_regs(struct net_device *dev, struct ethtool_regs *regs,
 		buf[i] = csrrd32(priv->mac_dev, i * 4);
 }
 
+static int tse_ethtool_set_link_ksettings(struct net_device *dev,
+					  const struct ethtool_link_ksettings *cmd)
+{
+	struct altera_tse_private *priv = netdev_priv(dev);
+
+	return phylink_ethtool_ksettings_set(priv->phylink, cmd);
+}
+
+static int tse_ethtool_get_link_ksettings(struct net_device *dev,
+					  struct ethtool_link_ksettings *cmd)
+{
+	struct altera_tse_private *priv = netdev_priv(dev);
+
+	return phylink_ethtool_ksettings_get(priv->phylink, cmd);
+}
+
 static const struct ethtool_ops tse_ethtool_ops = {
 	.get_drvinfo = tse_get_drvinfo,
 	.get_regs_len = tse_reglen,
@@ -231,8 +247,8 @@ static const struct ethtool_ops tse_ethtool_ops = {
 	.get_ethtool_stats = tse_fill_stats,
 	.get_msglevel = tse_get_msglevel,
 	.set_msglevel = tse_set_msglevel,
-	.get_link_ksettings = phy_ethtool_get_link_ksettings,
-	.set_link_ksettings = phy_ethtool_set_link_ksettings,
+	.get_link_ksettings = tse_ethtool_get_link_ksettings,
+	.set_link_ksettings = tse_ethtool_set_link_ksettings,
 	.get_ts_info = ethtool_op_get_ts_info,
 };
 

drivers/net/ethernet/altera/altera_tse_main.c

@@ -32,6 +32,7 @@
 #include <linux/of_mdio.h>
 #include <linux/of_net.h>
 #include <linux/of_platform.h>
+#include <linux/pcs-altera-tse.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
 #include <linux/skbuff.h>
@@ -86,27 +87,6 @@ static inline u32 tse_tx_avail(struct altera_tse_private *priv)
 	return priv->tx_cons + priv->tx_ring_size - priv->tx_prod - 1;
 }
 
-/* PCS Register read/write functions
- */
-static u16 sgmii_pcs_read(struct altera_tse_private *priv, int regnum)
-{
-	return csrrd32(priv->mac_dev,
-		       tse_csroffs(mdio_phy0) + regnum * 4) & 0xffff;
-}
-
-static void sgmii_pcs_write(struct altera_tse_private *priv, int regnum,
-				u16 value)
-{
-	csrwr32(value, priv->mac_dev, tse_csroffs(mdio_phy0) + regnum * 4);
-}
-
-/* Check PCS scratch memory */
-static int sgmii_pcs_scratch_test(struct altera_tse_private *priv, u16 value)
-{
-	sgmii_pcs_write(priv, SGMII_PCS_SCRATCH, value);
-	return (sgmii_pcs_read(priv, SGMII_PCS_SCRATCH) == value);
-}
-
 /* MDIO specific functions
  */
 static int altera_tse_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
@@ -141,10 +121,10 @@ static int altera_tse_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 static int altera_tse_mdio_create(struct net_device *dev, unsigned int id)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
-	int ret;
 	struct device_node *mdio_node = NULL;
-	struct mii_bus *mdio = NULL;
 	struct device_node *child_node = NULL;
+	struct mii_bus *mdio = NULL;
+	int ret;
 
 	for_each_child_of_node(priv->device->of_node, child_node) {
 		if (of_device_is_compatible(child_node, "altr,tse-mdio")) {
@@ -236,8 +216,8 @@ static int tse_init_rx_buffer(struct altera_tse_private *priv,
 static void tse_free_rx_buffer(struct altera_tse_private *priv,
 			       struct tse_buffer *rxbuffer)
 {
-	struct sk_buff *skb = rxbuffer->skb;
 	dma_addr_t dma_addr = rxbuffer->dma_addr;
+	struct sk_buff *skb = rxbuffer->skb;
 
 	if (skb != NULL) {
 		if (dma_addr)
@@ -358,6 +338,7 @@ static inline void tse_rx_vlan(struct net_device *dev, struct sk_buff *skb)
 {
 	struct ethhdr *eth_hdr;
 	u16 vid;
+
 	if ((dev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
 	    !__vlan_get_tag(skb, &vid)) {
 		eth_hdr = (struct ethhdr *)skb->data;
@@ -371,10 +352,10 @@ static inline void tse_rx_vlan(struct net_device *dev, struct sk_buff *skb)
  */
 static int tse_rx(struct altera_tse_private *priv, int limit)
 {
-	unsigned int count = 0;
+	unsigned int entry = priv->rx_cons % priv->rx_ring_size;
 	unsigned int next_entry;
+	unsigned int count = 0;
 	struct sk_buff *skb;
-	unsigned int entry = priv->rx_cons % priv->rx_ring_size;
 	u32 rxstatus;
 	u16 pktlength;
 	u16 pktstatus;
@@ -448,10 +429,10 @@ static int tse_rx(struct altera_tse_private *priv, int limit)
 static int tse_tx_complete(struct altera_tse_private *priv)
 {
 	unsigned int txsize = priv->tx_ring_size;
-	u32 ready;
-	unsigned int entry;
 	struct tse_buffer *tx_buff;
+	unsigned int entry;
 	int txcomplete = 0;
+	u32 ready;
 
 	spin_lock(&priv->tx_lock);
 
@@ -497,8 +478,8 @@ static int tse_poll(struct napi_struct *napi, int budget)
 {
 	struct altera_tse_private *priv =
 			container_of(napi, struct altera_tse_private, napi);
-	int rxcomplete = 0;
 	unsigned long int flags;
+	int rxcomplete = 0;
 
 	tse_tx_complete(priv);
 
@@ -561,13 +542,13 @@ static irqreturn_t altera_isr(int irq, void *dev_id)
 static netdev_tx_t tse_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
+	unsigned int nopaged_len = skb_headlen(skb);
 	unsigned int txsize = priv->tx_ring_size;
-	unsigned int entry;
-	struct tse_buffer *buffer = NULL;
 	int nfrags = skb_shinfo(skb)->nr_frags;
-	unsigned int nopaged_len = skb_headlen(skb);
+	struct tse_buffer *buffer = NULL;
 	netdev_tx_t ret = NETDEV_TX_OK;
 	dma_addr_t dma_addr;
+	unsigned int entry;
 
 	spin_lock_bh(&priv->tx_lock);
 
@@ -619,117 +600,6 @@ static netdev_tx_t tse_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	return ret;
 }
 
-/* Called every time the controller might need to be made
- * aware of new link state.  The PHY code conveys this
- * information through variables in the phydev structure, and this
- * function converts those variables into the appropriate
- * register values, and can bring down the device if needed.
- */
-static void altera_tse_adjust_link(struct net_device *dev)
-{
-	struct altera_tse_private *priv = netdev_priv(dev);
-	struct phy_device *phydev = dev->phydev;
-	int new_state = 0;
-
-	/* only change config if there is a link */
-	spin_lock(&priv->mac_cfg_lock);
-	if (phydev->link) {
-		/* Read old config */
-		u32 cfg_reg = ioread32(&priv->mac_dev->command_config);
-
-		/* Check duplex */
-		if (phydev->duplex != priv->oldduplex) {
-			new_state = 1;
-			if (!(phydev->duplex))
-				cfg_reg |= MAC_CMDCFG_HD_ENA;
-			else
-				cfg_reg &= ~MAC_CMDCFG_HD_ENA;
-
-			netdev_dbg(priv->dev, "%s: Link duplex = 0x%x\n",
-				   dev->name, phydev->duplex);
-
-			priv->oldduplex = phydev->duplex;
-		}
-
-		/* Check speed */
-		if (phydev->speed != priv->oldspeed) {
-			new_state = 1;
-			switch (phydev->speed) {
-			case 1000:
-				cfg_reg |= MAC_CMDCFG_ETH_SPEED;
-				cfg_reg &= ~MAC_CMDCFG_ENA_10;
-				break;
-			case 100:
-				cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
-				cfg_reg &= ~MAC_CMDCFG_ENA_10;
-				break;
-			case 10:
-				cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
-				cfg_reg |= MAC_CMDCFG_ENA_10;
-				break;
-			default:
-				if (netif_msg_link(priv))
-					netdev_warn(dev, "Speed (%d) is not 10/100/1000!\n",
-						    phydev->speed);
-				break;
-			}
-			priv->oldspeed = phydev->speed;
-		}
-		iowrite32(cfg_reg, &priv->mac_dev->command_config);
-
-		if (!priv->oldlink) {
-			new_state = 1;
-			priv->oldlink = 1;
-		}
-	} else if (priv->oldlink) {
-		new_state = 1;
-		priv->oldlink = 0;
-		priv->oldspeed = 0;
-		priv->oldduplex = -1;
-	}
-
-	if (new_state && netif_msg_link(priv))
-		phy_print_status(phydev);
-
-	spin_unlock(&priv->mac_cfg_lock);
-}
-static struct phy_device *connect_local_phy(struct net_device *dev)
-{
-	struct altera_tse_private *priv = netdev_priv(dev);
-	struct phy_device *phydev = NULL;
-	char phy_id_fmt[MII_BUS_ID_SIZE + 3];
-
-	if (priv->phy_addr != POLL_PHY) {
-		snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT,
-			 priv->mdio->id, priv->phy_addr);
-
-		netdev_dbg(dev, "trying to attach to %s\n", phy_id_fmt);
-
-		phydev = phy_connect(dev, phy_id_fmt, &altera_tse_adjust_link,
-				     priv->phy_iface);
-		if (IS_ERR(phydev)) {
-			netdev_err(dev, "Could not attach to PHY\n");
-			phydev = NULL;
-		}
-
-	} else {
-		int ret;
-		phydev = phy_find_first(priv->mdio);
-		if (phydev == NULL) {
-			netdev_err(dev, "No PHY found\n");
-			return phydev;
-		}
-
-		ret = phy_connect_direct(dev, phydev, &altera_tse_adjust_link,
-				priv->phy_iface);
-		if (ret != 0) {
-			netdev_err(dev, "Could not attach to PHY\n");
-			phydev = NULL;
-		}
-	}
-	return phydev;
-}
-
 static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
@@ -768,91 +638,6 @@ static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev)
 	return 0;
 }
 
-/* Initialize driver's PHY state, and attach to the PHY
- */
-static int init_phy(struct net_device *dev)
-{
-	struct altera_tse_private *priv = netdev_priv(dev);
-	struct phy_device *phydev;
-	struct device_node *phynode;
-	bool fixed_link = false;
-	int rc = 0;
-
-	/* Avoid init phy in case of no phy present */
-	if (!priv->phy_iface)
-		return 0;
-
-	priv->oldlink = 0;
-	priv->oldspeed = 0;
-	priv->oldduplex = -1;
-
-	phynode = of_parse_phandle(priv->device->of_node, "phy-handle", 0);
-
-	if (!phynode) {
-		/* check if a fixed-link is defined in device-tree */
-		if (of_phy_is_fixed_link(priv->device->of_node)) {
-			rc = of_phy_register_fixed_link(priv->device->of_node);
-			if (rc < 0) {
-				netdev_err(dev, "cannot register fixed PHY\n");
-				return rc;
-			}
-
-			/* In the case of a fixed PHY, the DT node associated
-			 * to the PHY is the Ethernet MAC DT node.
-			 */
-			phynode = of_node_get(priv->device->of_node);
-			fixed_link = true;
-
-			netdev_dbg(dev, "fixed-link detected\n");
-			phydev = of_phy_connect(dev, phynode,
-						&altera_tse_adjust_link,
-						0, priv->phy_iface);
-		} else {
-			netdev_dbg(dev, "no phy-handle found\n");
-			if (!priv->mdio) {
-				netdev_err(dev, "No phy-handle nor local mdio specified\n");
-				return -ENODEV;
-			}
-			phydev = connect_local_phy(dev);
-		}
-	} else {
-		netdev_dbg(dev, "phy-handle found\n");
-		phydev = of_phy_connect(dev, phynode,
-			&altera_tse_adjust_link, 0, priv->phy_iface);
-	}
-	of_node_put(phynode);
-
-	if (!phydev) {
-		netdev_err(dev, "Could not find the PHY\n");
-		if (fixed_link)
-			of_phy_deregister_fixed_link(priv->device->of_node);
-		return -ENODEV;
-	}
-
-	/* Stop Advertising 1000BASE Capability if interface is not GMII
-	 */
-	if ((priv->phy_iface == PHY_INTERFACE_MODE_MII) ||
-	    (priv->phy_iface == PHY_INTERFACE_MODE_RMII))
-		phy_set_max_speed(phydev, SPEED_100);
-
-	/* Broken HW is sometimes missing the pull-up resistor on the
-	 * MDIO line, which results in reads to non-existent devices returning
-	 * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent
-	 * device as well. If a fixed-link is used the phy_id is always 0.
-	 * Note: phydev->phy_id is the result of reading the UID PHY registers.
-	 */
-	if ((phydev->phy_id == 0) && !fixed_link) {
-		netdev_err(dev, "Bad PHY UID 0x%08x\n", phydev->phy_id);
-		phy_disconnect(phydev);
-		return -ENODEV;
-	}
-
-	netdev_dbg(dev, "attached to PHY %d UID 0x%08x Link = %d\n",
-		   phydev->mdio.addr, phydev->phy_id, phydev->link);
-
-	return 0;
-}
-
 static void tse_update_mac_addr(struct altera_tse_private *priv, const u8 *addr)
 {
 	u32 msb;
@@ -1012,8 +797,8 @@ static int tse_change_mtu(struct net_device *dev, int new_mtu)
 static void altera_tse_set_mcfilter(struct net_device *dev)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
-	int i;
 	struct netdev_hw_addr *ha;
+	int i;
 
 	/* clear the hash filter */
 	for (i = 0; i < 64; i++)
@@ -1087,74 +872,14 @@ static void tse_set_rx_mode(struct net_device *dev)
 	spin_unlock(&priv->mac_cfg_lock);
 }
 
-/* Initialise (if necessary) the SGMII PCS component
- */
-static int init_sgmii_pcs(struct net_device *dev)
-{
-	struct altera_tse_private *priv = netdev_priv(dev);
-	int n;
-	unsigned int tmp_reg = 0;
-
-	if (priv->phy_iface != PHY_INTERFACE_MODE_SGMII)
-		return 0; /* Nothing to do, not in SGMII mode */
-
-	/* The TSE SGMII PCS block looks a little like a PHY, it is
-	 * mapped into the zeroth MDIO space of the MAC and it has
-	 * ID registers like a PHY would.  Sadly this is often
-	 * configured to zeroes, so don't be surprised if it does
-	 * show 0x00000000.
-	 */
-
-	if (sgmii_pcs_scratch_test(priv, 0x0000) &&
-		sgmii_pcs_scratch_test(priv, 0xffff) &&
-		sgmii_pcs_scratch_test(priv, 0xa5a5) &&
-		sgmii_pcs_scratch_test(priv, 0x5a5a)) {
-		netdev_info(dev, "PCS PHY ID: 0x%04x%04x\n",
-				sgmii_pcs_read(priv, MII_PHYSID1),
-				sgmii_pcs_read(priv, MII_PHYSID2));
-	} else {
-		netdev_err(dev, "SGMII PCS Scratch memory test failed.\n");
-		return -ENOMEM;
-	}
-
-	/* Starting on page 5-29 of the MegaCore Function User Guide
-	 * Set SGMII Link timer to 1.6ms
-	 */
-	sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_0, 0x0D40);
-	sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_1, 0x03);
-
-	/* Enable SGMII Interface and Enable SGMII Auto Negotiation */
-	sgmii_pcs_write(priv, SGMII_PCS_IF_MODE, 0x3);
-
-	/* Enable Autonegotiation */
-	tmp_reg = sgmii_pcs_read(priv, MII_BMCR);
-	tmp_reg |= (BMCR_SPEED1000 | BMCR_FULLDPLX | BMCR_ANENABLE);
-	sgmii_pcs_write(priv, MII_BMCR, tmp_reg);
-
-	/* Reset PCS block */
-	tmp_reg |= BMCR_RESET;
-	sgmii_pcs_write(priv, MII_BMCR, tmp_reg);
-	for (n = 0; n < SGMII_PCS_SW_RESET_TIMEOUT; n++) {
-		if (!(sgmii_pcs_read(priv, MII_BMCR) & BMCR_RESET)) {
-			netdev_info(dev, "SGMII PCS block initialised OK\n");
-			return 0;
-		}
-		udelay(1);
-	}
-
-	/* We failed to reset the block, return a timeout */
-	netdev_err(dev, "SGMII PCS block reset failed.\n");
-	return -ETIMEDOUT;
-}
-
 /* Open and initialize the interface
  */
 static int tse_open(struct net_device *dev)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
+	unsigned long flags;
 	int ret = 0;
 	int i;
-	unsigned long int flags;
 
 	/* Reset and configure TSE MAC and probe associated PHY */
 	ret = priv->dmaops->init_dma(priv);
@@ -1171,14 +896,6 @@ static int tse_open(struct net_device *dev)
 		netdev_warn(dev, "TSE revision %x\n", priv->revision);
 
 	spin_lock(&priv->mac_cfg_lock);
-	/* no-op if MAC not operating in SGMII mode*/
-	ret = init_sgmii_pcs(dev);
-	if (ret) {
-		netdev_err(dev,
-			   "Cannot init the SGMII PCS (error: %d)\n", ret);
-		spin_unlock(&priv->mac_cfg_lock);
-		goto phy_error;
-	}
 
 	ret = reset_mac(priv);
 	/* Note that reset_mac will fail if the clocks are gated by the PHY
@@ -1236,8 +953,12 @@ static int tse_open(struct net_device *dev)
 
 	spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags);
 
-	if (dev->phydev)
-		phy_start(dev->phydev);
+	ret = phylink_of_phy_connect(priv->phylink, priv->device->of_node, 0);
+	if (ret) {
+		netdev_err(dev, "could not connect phylink (%d)\n", ret);
+		goto tx_request_irq_error;
+	}
+	phylink_start(priv->phylink);
 
 	napi_enable(&priv->napi);
 	netif_start_queue(dev);
@@ -1265,13 +986,10 @@ static int tse_open(struct net_device *dev)
 static int tse_shutdown(struct net_device *dev)
 {
 	struct altera_tse_private *priv = netdev_priv(dev);
-	int ret;
 	unsigned long int flags;
+	int ret;
 
-	/* Stop the PHY */
-	if (dev->phydev)
-		phy_stop(dev->phydev);
-
+	phylink_stop(priv->phylink);
 	netif_stop_queue(dev);
 	napi_disable(&priv->napi);
 
@@ -1317,11 +1035,79 @@ static struct net_device_ops altera_tse_netdev_ops = {
 	.ndo_validate_addr	= eth_validate_addr,
 };
 
+static void alt_tse_mac_an_restart(struct phylink_config *config)
+{
+}
+
+static void alt_tse_mac_config(struct phylink_config *config, unsigned int mode,
+			       const struct phylink_link_state *state)
+{
+	struct net_device *ndev = to_net_dev(config->dev);
+	struct altera_tse_private *priv = netdev_priv(ndev);
+
+	spin_lock(&priv->mac_cfg_lock);
+	reset_mac(priv);
+	tse_set_mac(priv, true);
+	spin_unlock(&priv->mac_cfg_lock);
+}
+
+static void alt_tse_mac_link_down(struct phylink_config *config,
+				  unsigned int mode, phy_interface_t interface)
+{
+}
+
+static void alt_tse_mac_link_up(struct phylink_config *config,
+				struct phy_device *phy, unsigned int mode,
+				phy_interface_t interface, int speed,
+				int duplex, bool tx_pause, bool rx_pause)
+{
+	struct net_device *ndev = to_net_dev(config->dev);
+	struct altera_tse_private *priv = netdev_priv(ndev);
+	u32 ctrl;
+
+	ctrl = csrrd32(priv->mac_dev, tse_csroffs(command_config));
+	ctrl &= ~(MAC_CMDCFG_ENA_10 | MAC_CMDCFG_ETH_SPEED | MAC_CMDCFG_HD_ENA);
+
+	if (duplex == DUPLEX_HALF)
+		ctrl |= MAC_CMDCFG_HD_ENA;
+
+	if (speed == SPEED_1000)
+		ctrl |= MAC_CMDCFG_ETH_SPEED;
+	else if (speed == SPEED_10)
+		ctrl |= MAC_CMDCFG_ENA_10;
+
+	spin_lock(&priv->mac_cfg_lock);
+	csrwr32(ctrl, priv->mac_dev, tse_csroffs(command_config));
+	spin_unlock(&priv->mac_cfg_lock);
+}
+
+static struct phylink_pcs *alt_tse_select_pcs(struct phylink_config *config,
+					      phy_interface_t interface)
+{
+	struct net_device *ndev = to_net_dev(config->dev);
+	struct altera_tse_private *priv = netdev_priv(ndev);
+
+	if (interface == PHY_INTERFACE_MODE_SGMII ||
+	    interface == PHY_INTERFACE_MODE_1000BASEX)
+		return priv->pcs;
+	else
+		return NULL;
+}
+
+static const struct phylink_mac_ops alt_tse_phylink_ops = {
+	.validate = phylink_generic_validate,
+	.mac_an_restart = alt_tse_mac_an_restart,
+	.mac_config = alt_tse_mac_config,
+	.mac_link_down = alt_tse_mac_link_down,
+	.mac_link_up = alt_tse_mac_link_up,
+	.mac_select_pcs = alt_tse_select_pcs,
+};
+
 static int request_and_map(struct platform_device *pdev, const char *name,
 			   struct resource **res, void __iomem **ptr)
 {
-	struct resource *region;
 	struct device *device = &pdev->dev;
+	struct resource *region;
 
 	*res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 	if (*res == NULL) {
@@ -1350,13 +1136,15 @@ static int request_and_map(struct platform_device *pdev, const char *name,
  */
 static int altera_tse_probe(struct platform_device *pdev)
 {
-	struct net_device *ndev;
-	int ret = -ENODEV;
+	const struct of_device_id *of_id = NULL;
+	struct altera_tse_private *priv;
 	struct resource *control_port;
 	struct resource *dma_res;
-	struct altera_tse_private *priv;
+	struct resource *pcs_res;
+	struct net_device *ndev;
 	void __iomem *descmap;
-	const struct of_device_id *of_id = NULL;
+	int pcs_reg_width = 2;
+	int ret = -ENODEV;
 
 	ndev = alloc_etherdev(sizeof(struct altera_tse_private));
 	if (!ndev) {
@@ -1467,6 +1255,17 @@ static int altera_tse_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_free_netdev;
 
+	/* SGMII PCS address space. The location can vary depending on how the
+	 * IP is integrated. We can have a resource dedicated to it at a specific
+	 * address space, but if it's not the case, we fallback to the mdiophy0
+	 * from the MAC's address space
+	 */
+	ret = request_and_map(pdev, "pcs", &pcs_res,
+			      &priv->pcs_base);
+	if (ret) {
+		priv->pcs_base = priv->mac_dev + tse_csroffs(mdio_phy0);
+		pcs_reg_width = 4;
+	}
 
 	/* Rx IRQ */
 	priv->rx_irq = platform_get_irq_byname(pdev, "rx_irq");
@@ -1590,11 +1389,31 @@ static int altera_tse_probe(struct platform_device *pdev)
 			 (unsigned long) control_port->start, priv->rx_irq,
 			 priv->tx_irq);
 
-	ret = init_phy(ndev);
-	if (ret != 0) {
-		netdev_err(ndev, "Cannot attach to PHY (error: %d)\n", ret);
+	priv->pcs = alt_tse_pcs_create(ndev, priv->pcs_base, pcs_reg_width);
+
+	priv->phylink_config.dev = &ndev->dev;
+	priv->phylink_config.type = PHYLINK_NETDEV;
+	priv->phylink_config.mac_capabilities = MAC_SYM_PAUSE | MAC_10 |
+						MAC_100 | MAC_1000FD;
+
+	phy_interface_set_rgmii(priv->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_MII,
+		  priv->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_GMII,
+		  priv->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_SGMII,
+		  priv->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_1000BASEX,
+		  priv->phylink_config.supported_interfaces);
+
+	priv->phylink = phylink_create(&priv->phylink_config,
+				       of_fwnode_handle(priv->device->of_node),
+				       priv->phy_iface, &alt_tse_phylink_ops);
+	if (IS_ERR(priv->phylink)) {
+		dev_err(&pdev->dev, "failed to create phylink\n");
 		goto err_init_phy;
 	}
+
 	return 0;
 
 err_init_phy:
@@ -1614,16 +1433,10 @@ static int altera_tse_remove(struct platform_device *pdev)
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct altera_tse_private *priv = netdev_priv(ndev);
 
-	if (ndev->phydev) {
-		phy_disconnect(ndev->phydev);
-
-		if (of_phy_is_fixed_link(priv->device->of_node))
-			of_phy_deregister_fixed_link(priv->device->of_node);
-	}
-
 	platform_set_drvdata(pdev, NULL);
 	altera_tse_mdio_destroy(ndev);
 	unregister_netdev(ndev);
+	phylink_destroy(priv->phylink);
 	free_netdev(ndev);
 
 	return 0;

drivers/net/pcs/Kconfig

@@ -26,4 +26,10 @@ config PCS_RZN1_MIIC
 	  on RZ/N1 SoCs. This PCS converts MII to RMII/RGMII or can be set in
 	  pass-through mode for MII.
 
+config PCS_ALTERA_TSE
+	tristate
+	help
+	  This module provides helper functions for the Altera Triple Speed
+	  Ethernet SGMII PCS, that can be found on the Intel Socfpga family.
+
 endmenu

drivers/net/pcs/Makefile

@@ -6,3 +6,4 @@ pcs_xpcs-$(CONFIG_PCS_XPCS)	:= pcs-xpcs.o pcs-xpcs-nxp.o
 obj-$(CONFIG_PCS_XPCS)		+= pcs_xpcs.o
 obj-$(CONFIG_PCS_LYNX)		+= pcs-lynx.o
 obj-$(CONFIG_PCS_RZN1_MIIC)	+= pcs-rzn1-miic.o
+obj-$(CONFIG_PCS_ALTERA_TSE)	+= pcs-altera-tse.o

drivers/net/pcs/pcs-altera-tse.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 Bootlin
+ *
+ * Maxime Chevallier <maxime.chevallier@bootlin.com>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/phy.h>
+#include <linux/phylink.h>
+#include <linux/pcs-altera-tse.h>
+
+/* SGMII PCS register addresses
+ */
+#define SGMII_PCS_SCRATCH	0x10
+#define SGMII_PCS_REV		0x11
+#define SGMII_PCS_LINK_TIMER_0	0x12
+#define   SGMII_PCS_LINK_TIMER_REG(x)		(0x12 + (x))
+#define SGMII_PCS_LINK_TIMER_1	0x13
+#define SGMII_PCS_IF_MODE	0x14
+#define   PCS_IF_MODE_SGMII_ENA		BIT(0)
+#define   PCS_IF_MODE_USE_SGMII_AN	BIT(1)
+#define   PCS_IF_MODE_SGMI_SPEED_MASK	GENMASK(3, 2)
+#define   PCS_IF_MODE_SGMI_SPEED_10	(0 << 2)
+#define   PCS_IF_MODE_SGMI_SPEED_100	(1 << 2)
+#define   PCS_IF_MODE_SGMI_SPEED_1000	(2 << 2)
+#define   PCS_IF_MODE_SGMI_HALF_DUPLEX	BIT(4)
+#define   PCS_IF_MODE_SGMI_PHY_AN	BIT(5)
+#define SGMII_PCS_DIS_READ_TO	0x15
+#define SGMII_PCS_READ_TO	0x16
+#define SGMII_PCS_SW_RESET_TIMEOUT 100 /* usecs */
+
+struct altera_tse_pcs {
+	struct phylink_pcs pcs;
+	void __iomem *base;
+	int reg_width;
+};
+
+static struct altera_tse_pcs *phylink_pcs_to_tse_pcs(struct phylink_pcs *pcs)
+{
+	return container_of(pcs, struct altera_tse_pcs, pcs);
+}
+
+static u16 tse_pcs_read(struct altera_tse_pcs *tse_pcs, int regnum)
+{
+	if (tse_pcs->reg_width == 4)
+		return readl(tse_pcs->base + regnum * 4);
+	else
+		return readw(tse_pcs->base + regnum * 2);
+}
+
+static void tse_pcs_write(struct altera_tse_pcs *tse_pcs, int regnum,
+			  u16 value)
+{
+	if (tse_pcs->reg_width == 4)
+		writel(value, tse_pcs->base + regnum * 4);
+	else
+		writew(value, tse_pcs->base + regnum * 2);
+}
+
+static int tse_pcs_reset(struct altera_tse_pcs *tse_pcs)
+{
+	int i = 0;
+	u16 bmcr;
+
+	/* Reset PCS block */
+	bmcr = tse_pcs_read(tse_pcs, MII_BMCR);
+	bmcr |= BMCR_RESET;
+	tse_pcs_write(tse_pcs, MII_BMCR, bmcr);
+
+	for (i = 0; i < SGMII_PCS_SW_RESET_TIMEOUT; i++) {
+		if (!(tse_pcs_read(tse_pcs, MII_BMCR) & BMCR_RESET))
+			return 0;
+		udelay(1);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int alt_tse_pcs_validate(struct phylink_pcs *pcs,
+				unsigned long *supported,
+				const struct phylink_link_state *state)
+{
+	if (state->interface == PHY_INTERFACE_MODE_SGMII ||
+	    state->interface == PHY_INTERFACE_MODE_1000BASEX)
+		return 1;
+
+	return -EINVAL;
+}
+
+static int alt_tse_pcs_config(struct phylink_pcs *pcs, unsigned int mode,
+			      phy_interface_t interface,
+			      const unsigned long *advertising,
+			      bool permit_pause_to_mac)
+{
+	struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs);
+	u32 ctrl, if_mode;
+
+	ctrl = tse_pcs_read(tse_pcs, MII_BMCR);
+	if_mode = tse_pcs_read(tse_pcs, SGMII_PCS_IF_MODE);
+
+	/* Set link timer to 1.6ms, as per the MegaCore Function User Guide */
+	tse_pcs_write(tse_pcs, SGMII_PCS_LINK_TIMER_0, 0x0D40);
+	tse_pcs_write(tse_pcs, SGMII_PCS_LINK_TIMER_1, 0x03);
+
+	if (interface == PHY_INTERFACE_MODE_SGMII) {
+		if_mode |= PCS_IF_MODE_USE_SGMII_AN | PCS_IF_MODE_SGMII_ENA;
+	} else if (interface == PHY_INTERFACE_MODE_1000BASEX) {
+		if_mode &= ~(PCS_IF_MODE_USE_SGMII_AN | PCS_IF_MODE_SGMII_ENA);
+		if_mode |= PCS_IF_MODE_SGMI_SPEED_1000;
+	}
+
+	ctrl |= (BMCR_SPEED1000 | BMCR_FULLDPLX | BMCR_ANENABLE);
+
+	tse_pcs_write(tse_pcs, MII_BMCR, ctrl);
+	tse_pcs_write(tse_pcs, SGMII_PCS_IF_MODE, if_mode);
+
+	return tse_pcs_reset(tse_pcs);
+}
+
+static void alt_tse_pcs_get_state(struct phylink_pcs *pcs,
+				  struct phylink_link_state *state)
+{
+	struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs);
+	u16 bmsr, lpa;
+
+	bmsr = tse_pcs_read(tse_pcs, MII_BMSR);
+	lpa = tse_pcs_read(tse_pcs, MII_LPA);
+
+	phylink_mii_c22_pcs_decode_state(state, bmsr, lpa);
+}
+
+static void alt_tse_pcs_an_restart(struct phylink_pcs *pcs)
+{
+	struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs);
+	u16 bmcr;
+
+	bmcr = tse_pcs_read(tse_pcs, MII_BMCR);
+	bmcr |= BMCR_ANRESTART;
+	tse_pcs_write(tse_pcs, MII_BMCR, bmcr);
+
+	/* This PCS seems to require a soft reset to re-sync the AN logic */
+	tse_pcs_reset(tse_pcs);
+}
+
+static const struct phylink_pcs_ops alt_tse_pcs_ops = {
+	.pcs_validate = alt_tse_pcs_validate,
+	.pcs_get_state = alt_tse_pcs_get_state,
+	.pcs_config = alt_tse_pcs_config,
+	.pcs_an_restart = alt_tse_pcs_an_restart,
+};
+
+struct phylink_pcs *alt_tse_pcs_create(struct net_device *ndev,
+				       void __iomem *pcs_base, int reg_width)
+{
+	struct altera_tse_pcs *tse_pcs;
+
+	if (reg_width != 4 && reg_width != 2)
+		return ERR_PTR(-EINVAL);
+
+	tse_pcs = devm_kzalloc(&ndev->dev, sizeof(*tse_pcs), GFP_KERNEL);
+	if (!tse_pcs)
+		return ERR_PTR(-ENOMEM);
+
+	tse_pcs->pcs.ops = &alt_tse_pcs_ops;
+	tse_pcs->base = pcs_base;
+	tse_pcs->reg_width = reg_width;
+
+	return &tse_pcs->pcs;
+}
+EXPORT_SYMBOL_GPL(alt_tse_pcs_create);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Altera TSE PCS driver");
+MODULE_AUTHOR("Maxime Chevallier <maxime.chevallier@bootlin.com>");

include/linux/pcs-altera-tse.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Bootlin
+ *
+ * Maxime Chevallier <maxime.chevallier@bootlin.com>
+ */
+
+#ifndef __LINUX_PCS_ALTERA_TSE_H
+#define __LINUX_PCS_ALTERA_TSE_H
+
+struct phylink_pcs;
+struct net_device;
+
+struct phylink_pcs *alt_tse_pcs_create(struct net_device *ndev,
+				       void __iomem *pcs_base, int reg_width);
+
+#endif /* __LINUX_PCS_ALTERA_TSE_H */