[net-next PATCH v2 00/14] Add PCS core support

[net-next PATCH v2 00/14] Add PCS core support

[Sean Anderson]

This series adds support for creating PCSs as devices on a bus with a
driver (patch 3). As initial users,

- The Lynx PCS (and all of its users) is converted to this system (patch 5)
- The Xilinx PCS is broken out from the AXI Ethernet driver (patches 6-8)
- The Cadence MACB driver is converted to support external PCSs (namely
  the Xilinx PCS) (patches 9-10).

The last few patches add device links for pcs-handle to improve boot times,
and add compatibles for all Lynx PCSs.

This series depends on [1,2], and they have been included at the
beginning so CI will run. However, I expect them to be reviewed/applied
outside the net-next tree.

Care has been taken to ensure backwards-compatibility. The main source
of this is that many PCS devices lack compatibles and get detected as
PHYs. To address this, pcs_get_by_fwnode_compat allows drivers to edit
the devicetree to add appropriate compatibles.

There is another series [3] with the same goal by Christian Marangi. In
comparison, I believe this series

- Implements a simpler and more-robust method of PCS access.
- Provides a more-direct upgrade path for existing MAC and PCS drivers.

Due to popular demand, I have added support for #pcs-cells with this
revision.

[1] https://lore.kernel.org/all/20250407222134.2280553-1-sean.anderson@linux.dev/
[2] https://lore.kernel.org/all/20250407223714.2287202-1-sean.anderson@linux.dev/
[3] https://lore.kernel.org/netdev/20250406221423.9723-1-ansuelsmth@gmail.com/

Changes in v2:
- Add fallbacks for pcs_get* and pcs_put
- Add support for #pcs-cells
- Change base compatible to just xlnx,pcs
- Change compatible to just xlnx,pcs
- Defer devicetree updates for another series
- Drop #clock-cells description
- Drop PCS_ALTERA_TSE which was accidentally added while rebasing
- Move #clock-cells after compatible
- Move update to macb_pcs_get_state to previous patch
- Remove outdated comment
- Remove second example
- Remove unused variable
- Remove unused variable lynx_properties
- Rename pcs-modes to xlnx,pcs-modes
- Reorder pcs_handle to come before suffix props
- Reword commit message
- Rework xilinx_pcs_validate to just clear out half-duplex modes instead
  of constraining modes based on the interface.

Sean Anderson (13):
  dt-bindings: net: Add Xilinx PCS
  device property: Add optional nargs_prop for get_reference_args
  device property: Add fwnode_property_get_reference_optional_args
  scripts: kernel-doc: fix parsing function-like typedefs (again)
  net: phylink: Support setting PCS link change callbacks
  net: pcs: Add subsystem
  net: pcs: lynx: Convert to an MDIO driver
  net: phy: Export some functions
  net: pcs: Add Xilinx PCS driver
  net: axienet: Convert to use PCS subsystem
  net: macb: Move most of mac_config to mac_prepare
  net: macb: Support external PCSs
  of: property: Add device link support for PCS

Vladimir Oltean (1):
  net: dsa: ocelot: suppress PHY device scanning on the internal MDIO
    bus

 .../devicetree/bindings/net/xilinx,pcs.yaml   | 115 +++
 Documentation/networking/index.rst            |   1 +
 Documentation/networking/kapi.rst             |   4 +
 Documentation/networking/pcs.rst              | 107 +++
 MAINTAINERS                                   |   8 +
 drivers/base/property.c                       |  50 +-
 drivers/base/swnode.c                         |  13 +-
 drivers/net/dsa/ocelot/Kconfig                |   4 +
 drivers/net/dsa/ocelot/felix_vsc9959.c        |  15 +-
 drivers/net/dsa/ocelot/seville_vsc9953.c      |  16 +-
 drivers/net/ethernet/altera/Kconfig           |   2 +
 drivers/net/ethernet/altera/altera_tse_main.c |   7 +-
 drivers/net/ethernet/cadence/macb.h           |   1 +
 drivers/net/ethernet/cadence/macb_main.c      | 229 +++--
 drivers/net/ethernet/freescale/dpaa/Kconfig   |   2 +-
 drivers/net/ethernet/freescale/dpaa2/Kconfig  |   3 +
 .../net/ethernet/freescale/dpaa2/dpaa2-mac.c  |  11 +-
 drivers/net/ethernet/freescale/enetc/Kconfig  |   2 +
 .../net/ethernet/freescale/enetc/enetc_pf.c   |   8 +-
 .../net/ethernet/freescale/enetc/enetc_pf.h   |   1 -
 .../freescale/enetc/enetc_pf_common.c         |   4 +-
 drivers/net/ethernet/freescale/fman/Kconfig   |   4 +-
 .../net/ethernet/freescale/fman/fman_memac.c  |  27 +-
 drivers/net/ethernet/stmicro/stmmac/Kconfig   |   3 +
 .../ethernet/stmicro/stmmac/dwmac-socfpga.c   |   6 +-
 drivers/net/ethernet/xilinx/Kconfig           |   1 +
 drivers/net/ethernet/xilinx/xilinx_axienet.h  |   4 +-
 .../net/ethernet/xilinx/xilinx_axienet_main.c | 104 +--
 drivers/net/pcs/Kconfig                       |  45 +-
 drivers/net/pcs/Makefile                      |   4 +
 drivers/net/pcs/core.c                        | 782 ++++++++++++++++++
 drivers/net/pcs/pcs-lynx.c                    | 110 +--
 drivers/net/pcs/pcs-xilinx.c                  | 479 +++++++++++
 drivers/net/phy/mdio_device.c                 |   1 +
 drivers/net/phy/phy_device.c                  |   3 +-
 drivers/net/phy/phylink.c                     |  24 +-
 drivers/of/property.c                         |  12 +-
 include/linux/fwnode.h                        |   2 +-
 include/linux/pcs-lynx.h                      |  13 +-
 include/linux/pcs-xilinx.h                    |  36 +
 include/linux/pcs.h                           | 195 +++++
 include/linux/phy.h                           |   1 +
 include/linux/phylink.h                       |  27 +-
 include/linux/property.h                      |   4 +
 scripts/kernel-doc                            |   2 +-
 45 files changed, 2181 insertions(+), 311 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/xilinx,pcs.yaml
 create mode 100644 Documentation/networking/pcs.rst
 create mode 100644 drivers/net/pcs/core.c
 create mode 100644 drivers/net/pcs/pcs-xilinx.c
 create mode 100644 include/linux/pcs-xilinx.h
 create mode 100644 include/linux/pcs.h

-- 
2.35.1.1320.gc452695387.dirty

[net-next PATCH v2 10/14] net: pcs: Add Xilinx PCS driver

[Sean Anderson]

This adds support for the Xilinx 1G/2.5G Ethernet PCS/PMA or SGMII device.
This is a soft device which converts between GMII and either SGMII,
1000Base-X, or 2500Base-X. If configured correctly, it can also switch
between SGMII and 1000BASE-X at runtime. Thoretically this is also possible
for 2500Base-X, but that requires reconfiguring the serdes. The exact
capabilities depend on synthesis parameters, so they are read from the
devicetree.

This device has a c22-compliant PHY interface, so for the most part we can
just use the phylink helpers. This device supports an interrupt which is
triggered on autonegotiation completion. I'm not sure how useful this is,
since we can never detect a link down (in the PCS).

This device supports sharing some logic between different implementations
of the device. In this case, one device contains the "shared logic" and the
clocks are connected to other devices. To coordinate this, one device
registers a clock that the other devices can request.  The clock is enabled
in the probe function by releasing the device from reset. There are no othe
software controls, so the clock ops are empty.

Later in this series, we will convert the Xilinx AXI Ethernet driver to use
this PCS. To help out, we provide a compatibility function to bind this
driver in the event the MDIO device has no compatible.

Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
---

Changes in v2:
- Add support for #pcs-cells
- Change compatible to just xlnx,pcs
- Drop PCS_ALTERA_TSE which was accidentally added while rebasing
- Rework xilinx_pcs_validate to just clear out half-duplex modes instead
  of constraining modes based on the interface.

 MAINTAINERS                  |   6 +
 drivers/net/pcs/Kconfig      |  22 ++
 drivers/net/pcs/Makefile     |   2 +
 drivers/net/pcs/pcs-xilinx.c | 479 +++++++++++++++++++++++++++++++++++
 include/linux/pcs-xilinx.h   |  36 +++
 5 files changed, 545 insertions(+)
 create mode 100644 drivers/net/pcs/pcs-xilinx.c
 create mode 100644 include/linux/pcs-xilinx.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 9d3b3788a005..452096e6b04f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -26160,6 +26160,12 @@ L:	netdev@vger.kernel.org
 S:	Orphan
 F:	drivers/net/ethernet/xilinx/ll_temac*
 
+XILINX PCS DRIVER
+M:	Sean Anderson <sean.anderson@linux.dev>
+S:	Maintained
+F:	Documentation/devicetree/bindings/net/xilinx,pcs.yaml
+F:	drivers/net/pcs/pcs-xilinx.c
+
 XILINX PWM DRIVER
 M:	Sean Anderson <sean.anderson@seco.com>
 S:	Maintained
diff --git a/drivers/net/pcs/Kconfig b/drivers/net/pcs/Kconfig
index 91ff59899aaf..261d2fd29fc7 100644
--- a/drivers/net/pcs/Kconfig
+++ b/drivers/net/pcs/Kconfig
@@ -50,4 +50,26 @@ 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_XILINX
+	depends on OF
+	depends on GPIOLIB
+	depends on COMMON_CLK
+	depends on PCS
+	select MDIO_DEVICE
+	select PHYLINK
+	default XILINX_AXI_EMAC
+	tristate "Xilinx PCS driver"
+	help
+	  PCS driver for the Xilinx 1G/2.5G Ethernet PCS/PMA or SGMII device.
+	  This device can either act as a PCS+PMA for 1000BASE-X or 2500BASE-X,
+	  or as a GMII-to-SGMII bridge. It can also switch between 1000BASE-X
+	  and SGMII dynamically if configured correctly when synthesized.
+	  Typical applications use this device on an FPGA connected to a GEM or
+	  TEMAC on the GMII side. The other side is typically connected to
+	  on-device gigabit transceivers, off-device SERDES devices using TBI,
+	  or LVDS IO resources directly.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pcs-xilinx.
+
 endmenu
diff --git a/drivers/net/pcs/Makefile b/drivers/net/pcs/Makefile
index 35e3324fc26e..347afd91f034 100644
--- a/drivers/net/pcs/Makefile
+++ b/drivers/net/pcs/Makefile
@@ -10,3 +10,5 @@ obj-$(CONFIG_PCS_XPCS)		+= pcs_xpcs.o
 obj-$(CONFIG_PCS_LYNX)		+= pcs-lynx.o
 obj-$(CONFIG_PCS_MTK_LYNXI)	+= pcs-mtk-lynxi.o
 obj-$(CONFIG_PCS_RZN1_MIIC)	+= pcs-rzn1-miic.o
+obj-$(CONFIG_PCS_ALTERA_TSE)	+= pcs-altera-tse.o
+obj-$(CONFIG_PCS_XILINX)	+= pcs-xilinx.o
diff --git a/drivers/net/pcs/pcs-xilinx.c b/drivers/net/pcs/pcs-xilinx.c
new file mode 100644
index 000000000000..3439f140a89a
--- /dev/null
+++ b/drivers/net/pcs/pcs-xilinx.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021-25 Sean Anderson <sean.anderson@seco.com>
+ *
+ * This is the driver for the Xilinx 1G/2.5G Ethernet PCS/PMA or SGMII LogiCORE
+ * IP. A typical setup will look something like
+ *
+ * MAC <--GMII--> PCS/PMA <--1000BASE-X--> SFP module (PMD)
+ *
+ * The IEEE model mostly describes this device, but the PCS layer has a
+ * separate sublayer for 8b/10b en/decoding:
+ *
+ * - When using a device-specific transceiver (serdes), the serdes handles 8b/10b
+ *   en/decoding and PMA functions. The IP implements other PCS functions.
+ * - When using LVDS IO resources, the IP implements PCS and PMA functions,
+ *   including 8b/10b en/decoding and (de)serialization.
+ * - When using an external serdes (accessed via TBI), the IP implements all
+ *   PCS functions, including 8b/10b en/decoding.
+ *
+ * The link to the PMD is not modeled by this driver, except for refclk. It is
+ * assumed that the serdes (if present) needs no configuration, though it
+ * should be fairly easy to add support. It is also possible to go from SGMII
+ * to GMII (PHY mode), but this is not supported.
+ *
+ * This driver was written with reference to PG047:
+ * https://docs.amd.com/r/en-US/pg047-gig-eth-pcs-pma
+ */
+
+#include <linux/bitmap.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iopoll.h>
+#include <linux/mdio.h>
+#include <linux/of.h>
+#include <linux/pcs.h>
+#include <linux/pcs-xilinx.h>
+#include <linux/phylink.h>
+#include <linux/property.h>
+
+#include "../phy/phy-caps.h"
+
+/* Vendor-specific MDIO registers */
+#define XILINX_PCS_ANICR 16 /* Auto-Negotiation Interrupt Control Register */
+#define XILINX_PCS_SSR   17 /* Standard Selection Register */
+
+#define XILINX_PCS_ANICR_IE BIT(0) /* Interrupt Enable */
+#define XILINX_PCS_ANICR_IS BIT(1) /* Interrupt Status */
+
+#define XILINX_PCS_SSR_SGMII BIT(0) /* Select SGMII standard */
+
+/**
+ * struct xilinx_pcs - Private data for Xilinx PCS devices
+ * @pcs: The phylink PCS
+ * @mdiodev: The mdiodevice used to access the PCS
+ * @refclk: The reference clock for the PMD
+ * @refclk_out: Optional reference clock for other PCSs using this PCS's shared
+ *              logic
+ * @reset: The reset line for the PCS
+ * @done: Optional GPIO for reset_done
+ * @irq: IRQ, or -EINVAL if polling
+ * @enabled: Set if @pcs.link_change is valid and we can call phylink_pcs_change()
+ */
+struct xilinx_pcs {
+	struct phylink_pcs pcs;
+	struct clk_hw refclk_out;
+	struct clk *refclk;
+	struct gpio_desc *reset, *done;
+	struct mdio_device *mdiodev;
+	int irq;
+	bool enabled;
+};
+
+static inline struct xilinx_pcs *pcs_to_xilinx(struct phylink_pcs *pcs)
+{
+	return container_of(pcs, struct xilinx_pcs, pcs);
+}
+
+static irqreturn_t xilinx_pcs_an_irq(int irq, void *dev_id)
+{
+	struct xilinx_pcs *xp = dev_id;
+
+	if (mdiodev_modify_changed(xp->mdiodev, XILINX_PCS_ANICR,
+				   XILINX_PCS_ANICR_IS, 0) <= 0)
+		return IRQ_NONE;
+
+	/* paired with xilinx_pcs_enable/disable; protects xp->pcs->link_change */
+	if (smp_load_acquire(&xp->enabled))
+		phylink_pcs_change(&xp->pcs, true);
+	return IRQ_HANDLED;
+}
+
+static int xilinx_pcs_enable(struct phylink_pcs *pcs)
+{
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+	struct device *dev = &xp->mdiodev->dev;
+	int ret;
+
+	if (xp->irq < 0)
+		return 0;
+
+	ret = mdiodev_modify(xp->mdiodev, XILINX_PCS_ANICR, 0,
+			     XILINX_PCS_ANICR_IE);
+	if (ret)
+		dev_err(dev, "could not clear IRQ enable: %d\n", ret);
+	else
+		/* paired with xilinx_pcs_an_irq */
+		smp_store_release(&xp->enabled, true);
+	return ret;
+}
+
+static void xilinx_pcs_disable(struct phylink_pcs *pcs)
+{
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+	struct device *dev = &xp->mdiodev->dev;
+	int err;
+
+	if (xp->irq < 0)
+		return;
+
+	WRITE_ONCE(xp->enabled, false);
+	/* paired with xilinx_pcs_an_irq */
+	smp_wmb();
+
+	err = mdiodev_modify(xp->mdiodev, XILINX_PCS_ANICR,
+			     XILINX_PCS_ANICR_IE, 0);
+	if (err)
+		dev_err(dev, "could not clear IRQ enable: %d\n", err);
+}
+
+static __ETHTOOL_DECLARE_LINK_MODE_MASK(half_duplex) __ro_after_init;
+
+static int xilinx_pcs_validate(struct phylink_pcs *pcs,
+			       unsigned long *supported,
+			       const struct phylink_link_state *state)
+{
+	linkmode_andnot(supported, supported, half_duplex);
+	return 0;
+}
+
+static void xilinx_pcs_get_state(struct phylink_pcs *pcs,
+				 unsigned int neg_mode,
+				 struct phylink_link_state *state)
+{
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+
+	phylink_mii_c22_pcs_get_state(xp->mdiodev, neg_mode, state);
+}
+
+static int xilinx_pcs_config(struct phylink_pcs *pcs, unsigned int neg_mode,
+			     phy_interface_t interface,
+			     const unsigned long *advertising,
+			     bool permit_pause_to_mac)
+{
+	int ret, changed = 0;
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+
+	if (test_bit(PHY_INTERFACE_MODE_SGMII, pcs->supported_interfaces) &&
+	    test_bit(PHY_INTERFACE_MODE_1000BASEX, pcs->supported_interfaces)) {
+		u16 ssr;
+
+		if (interface == PHY_INTERFACE_MODE_SGMII)
+			ssr = XILINX_PCS_SSR_SGMII;
+		else
+			ssr = 0;
+
+		changed = mdiodev_modify_changed(xp->mdiodev, XILINX_PCS_SSR,
+						 XILINX_PCS_SSR_SGMII, ssr);
+		if (changed < 0)
+			return changed;
+	}
+
+	ret = phylink_mii_c22_pcs_config(xp->mdiodev, interface, advertising,
+					 neg_mode);
+	return ret ?: changed;
+}
+
+static void xilinx_pcs_an_restart(struct phylink_pcs *pcs)
+{
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+
+	phylink_mii_c22_pcs_an_restart(xp->mdiodev);
+}
+
+static void xilinx_pcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
+			       phy_interface_t interface, int speed, int duplex)
+{
+	int bmcr;
+	struct xilinx_pcs *xp = pcs_to_xilinx(pcs);
+
+	if (phylink_autoneg_inband(mode))
+		return;
+
+	bmcr = mdiodev_read(xp->mdiodev, MII_BMCR);
+	if (bmcr < 0) {
+		dev_err(&xp->mdiodev->dev, "could not read BMCR (err=%d)\n",
+			bmcr);
+		return;
+	}
+
+	bmcr &= ~(BMCR_SPEED1000 | BMCR_SPEED100);
+	switch (speed) {
+	case SPEED_2500:
+	case SPEED_1000:
+		bmcr |= BMCR_SPEED1000;
+		break;
+	case SPEED_100:
+		bmcr |= BMCR_SPEED100;
+		break;
+	case SPEED_10:
+		bmcr |= BMCR_SPEED10;
+		break;
+	default:
+		dev_err(&xp->mdiodev->dev, "invalid speed %d\n", speed);
+	}
+
+	bmcr = mdiodev_write(xp->mdiodev, MII_BMCR, bmcr);
+	if (bmcr < 0)
+		dev_err(&xp->mdiodev->dev, "could not write BMCR (err=%d)\n",
+			bmcr);
+}
+
+static const struct phylink_pcs_ops xilinx_pcs_ops = {
+	.pcs_validate = xilinx_pcs_validate,
+	.pcs_enable = xilinx_pcs_enable,
+	.pcs_disable = xilinx_pcs_disable,
+	.pcs_get_state = xilinx_pcs_get_state,
+	.pcs_config = xilinx_pcs_config,
+	.pcs_an_restart = xilinx_pcs_an_restart,
+	.pcs_link_up = xilinx_pcs_link_up,
+};
+
+static const struct clk_ops xilinx_pcs_clk_ops = { };
+
+static const phy_interface_t xilinx_pcs_interfaces[] = {
+	PHY_INTERFACE_MODE_SGMII,
+	PHY_INTERFACE_MODE_1000BASEX,
+	PHY_INTERFACE_MODE_2500BASEX,
+};
+
+static int xilinx_pcs_probe(struct mdio_device *mdiodev)
+{
+	struct device *dev = &mdiodev->dev;
+	struct fwnode_handle *fwnode = dev->fwnode;
+	int ret, i, j, mode_count;
+	struct xilinx_pcs *xp;
+	const char **modes;
+	u32 phy_id;
+
+	xp = devm_kzalloc(dev, sizeof(*xp), GFP_KERNEL);
+	if (!xp)
+		return -ENOMEM;
+	xp->mdiodev = mdiodev;
+	dev_set_drvdata(dev, xp);
+
+	xp->irq = fwnode_irq_get_byname(fwnode, "an");
+	/* There's no _optional variant, so this is the best we've got */
+	if (xp->irq < 0 && xp->irq != -EINVAL)
+		return dev_err_probe(dev, xp->irq, "could not get IRQ\n");
+
+	mode_count = fwnode_property_string_array_count(fwnode,
+							"xlnx,pcs-modes");
+	if (!mode_count)
+		mode_count = -ENODATA;
+	if (mode_count < 0) {
+		dev_err(dev, "could not read xlnx,pcs-modes: %d", mode_count);
+		return mode_count;
+	}
+
+	modes = kcalloc(mode_count, sizeof(*modes), GFP_KERNEL);
+	if (!modes)
+		return -ENOMEM;
+
+	ret = fwnode_property_read_string_array(fwnode, "xlnx,pcs-modes",
+						modes, mode_count);
+	if (ret < 0) {
+		dev_err(dev, "could not read xlnx,pcs-modes: %d\n", ret);
+		kfree(modes);
+		return ret;
+	}
+
+	for (i = 0; i < mode_count; i++) {
+		for (j = 0; j < ARRAY_SIZE(xilinx_pcs_interfaces); j++) {
+			if (!strcmp(phy_modes(xilinx_pcs_interfaces[j]), modes[i])) {
+				__set_bit(xilinx_pcs_interfaces[j],
+					  xp->pcs.supported_interfaces);
+				goto next;
+			}
+		}
+
+		dev_err(dev, "invalid pcs-mode \"%s\"\n", modes[i]);
+		kfree(modes);
+		return -EINVAL;
+next:
+	}
+
+	kfree(modes);
+	if ((test_bit(PHY_INTERFACE_MODE_SGMII, xp->pcs.supported_interfaces) ||
+	     test_bit(PHY_INTERFACE_MODE_1000BASEX, xp->pcs.supported_interfaces)) &&
+	    test_bit(PHY_INTERFACE_MODE_2500BASEX, xp->pcs.supported_interfaces)) {
+		dev_err(dev,
+			"Switching from SGMII or 1000Base-X to 2500Base-X not supported\n");
+		return -EINVAL;
+	}
+
+	xp->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(xp->reset))
+		return dev_err_probe(dev, PTR_ERR(xp->reset),
+				     "could not get reset gpio\n");
+
+	xp->done = devm_gpiod_get_optional(dev, "done", GPIOD_IN);
+	if (IS_ERR(xp->done))
+		return dev_err_probe(dev, PTR_ERR(xp->done),
+				     "could not get done gpio\n");
+
+	xp->refclk = devm_clk_get_optional_enabled(dev, "refclk");
+	if (IS_ERR(xp->refclk))
+		return dev_err_probe(dev, PTR_ERR(xp->refclk),
+				     "could not get/enable reference clock\n");
+
+	gpiod_set_value_cansleep(xp->reset, 0);
+	if (xp->done) {
+		if (read_poll_timeout(gpiod_get_value_cansleep, ret, ret, 1000,
+				      100000, true, xp->done))
+			return dev_err_probe(dev, -ETIMEDOUT,
+					     "timed out waiting for reset\n");
+	} else {
+		/* Just wait for a while and hope we're done */
+		usleep_range(50000, 100000);
+	}
+
+	if (fwnode_property_present(fwnode, "#clock-cells")) {
+		const char *parent = "refclk";
+		struct clk_init_data init = {
+			.name = fwnode_get_name(fwnode),
+			.ops = &xilinx_pcs_clk_ops,
+			.parent_names = &parent,
+			.num_parents = 1,
+			.flags = 0,
+		};
+
+		xp->refclk_out.init = &init;
+		ret = devm_clk_hw_register(dev, &xp->refclk_out);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "could not register refclk\n");
+
+		ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+						  &xp->refclk_out);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "could not register refclk\n");
+	}
+
+	/* Sanity check */
+	ret = get_phy_c22_id(mdiodev->bus, mdiodev->addr, &phy_id);
+	if (ret) {
+		dev_err_probe(dev, ret, "could not read id\n");
+		return ret;
+	}
+	if ((phy_id & 0xfffffff0) != 0x01740c00)
+		dev_warn(dev, "unknown phy id %x\n", phy_id);
+
+	if (xp->irq < 0) {
+		xp->pcs.poll = true;
+	} else {
+		/* The IRQ is enabled by default; turn it off */
+		ret = mdiodev_write(xp->mdiodev, XILINX_PCS_ANICR, 0);
+		if (ret) {
+			dev_err(dev, "could not disable IRQ: %d\n", ret);
+			return ret;
+		}
+
+		/* Some PCSs have a bad habit of re-enabling their IRQ!
+		 * Request the IRQ in probe so we don't end up triggering the
+		 * spurious IRQ logic.
+		 */
+		ret = devm_request_threaded_irq(dev, xp->irq, NULL, xilinx_pcs_an_irq,
+						IRQF_SHARED | IRQF_ONESHOT,
+						dev_name(dev), xp);
+		if (ret) {
+			dev_err(dev, "could not request IRQ: %d\n", ret);
+			return ret;
+		}
+	}
+
+	xp->pcs.ops = &xilinx_pcs_ops;
+	ret = devm_pcs_register_provider(dev, pcs_xlate_single, &xp->pcs);
+	if (ret)
+		return dev_err_probe(dev, ret, "could not register PCS\n");
+
+	if (xp->irq < 0)
+		dev_info(dev, "probed with irq=poll\n");
+	else
+		dev_info(dev, "probed with irq=%d\n", xp->irq);
+	return 0;
+}
+
+static const struct of_device_id xilinx_pcs_of_match[] = {
+	{ .compatible = "xlnx,pcs", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xilinx_timer_of_match);
+
+static struct mdio_driver xilinx_pcs_driver = {
+	.probe = xilinx_pcs_probe,
+	.mdiodrv.driver = {
+		.name = "xilinx-pcs",
+		.of_match_table = of_match_ptr(xilinx_pcs_of_match),
+		.suppress_bind_attrs = true,
+	},
+};
+
+static int __init xilinx_pcs_init(void)
+{
+	phy_caps_linkmodes(LINK_CAPA_10HD | LINK_CAPA_100HD | LINK_CAPA_1000HD,
+			   half_duplex);
+	return mdio_driver_register(&xilinx_pcs_driver);
+}
+module_init(xilinx_pcs_init);
+
+static void __exit xilinx_pcs_exit(void)
+{
+	mdio_driver_unregister(&xilinx_pcs_driver);
+}
+module_exit(xilinx_pcs_exit)
+
+static int axienet_xilinx_pcs_fixup(struct of_changeset *ocs,
+				    struct device_node *np, void *data)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	unsigned int interface, mode_count, mode = 0;
+	const unsigned long *interfaces = data;
+	const char **modes;
+	int ret;
+
+	mode_count = bitmap_weight(interfaces, PHY_INTERFACE_MODE_MAX);
+	WARN_ON_ONCE(!mode_count);
+	modes = kcalloc(mode_count, sizeof(*modes), GFP_KERNEL);
+	if (!modes)
+		return -ENOMEM;
+
+	for_each_set_bit(interface, interfaces, PHY_INTERFACE_MODE_MAX)
+		modes[mode++] = phy_modes(interface);
+	ret = of_changeset_add_prop_string_array(ocs, np, "xlnx,pcs-modes",
+						 modes, mode_count);
+	kfree(modes);
+	if (ret)
+		return ret;
+
+	return of_changeset_add_prop_string(ocs, np, "compatible",
+					    "xlnx,pcs");
+#else
+	return -ENODEV;
+#endif
+}
+
+struct phylink_pcs *axienet_xilinx_pcs_get(struct device *dev,
+					   const unsigned long *interfaces)
+{
+	struct fwnode_reference_args args;
+	struct phylink_pcs *pcs;
+	int ret;
+
+	ret = pcs_find_fwnode(dev_fwnode(dev), NULL, "phy-handle", false,
+			      &args);
+	if (ret)
+		return ERR_PTR(ret);
+
+	pcs = pcs_get_by_fwnode_compat(dev, args.fwnode,
+				       axienet_xilinx_pcs_fixup,
+				       (void *)interfaces);
+	fwnode_handle_put(args.fwnode);
+	return pcs;
+}
+
+MODULE_ALIAS("platform:xilinx-pcs");
+MODULE_DESCRIPTION("Xilinx PCS driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/pcs-xilinx.h b/include/linux/pcs-xilinx.h
new file mode 100644
index 000000000000..409057fbdf34
--- /dev/null
+++ b/include/linux/pcs-xilinx.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2024 Sean Anderson <sean.anderson@seco.com>
+ */
+
+#ifndef PCS_XILINX_H
+#define PCS_XILINX_H
+
+#include <linux/err.h>
+
+struct device;
+struct phylink_pcs;
+
+#ifdef CONFIG_PCS_XILINX
+/**
+ * axienet_xilinx_pcs_get() - Compatibility function for the AXI Ethernet driver
+ * @dev: The MAC device
+ * @interfaces: The interfaces to use as a fallback
+ *
+ * This is a helper function for the AXI Ethernet driver to ensure backwards
+ * compatibility with device trees which do not include compatible strings for
+ * the PCS. It should not be used by new code.
+ *
+ * Return: a PCS, or an error pointer
+ */
+struct phylink_pcs *axienet_xilinx_pcs_get(struct device *dev,
+					   const unsigned long *interfaces);
+#else
+static inline struct phylink_pcs *
+axienet_xilinx_pcs_get(struct device *dev, const unsigned long *interfaces)
+{
+	return ERR_PTR(-ENODEV);
+}
+#endif
+
+#endif /* PCS_XILINX_H */
-- 
2.35.1.1320.gc452695387.dirty

[net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem

[Sean Anderson]

Convert the AXI Ethernet driver to use the PCS subsystem, including the
new Xilinx PCA/PMA driver. Unfortunately, we must use a helper to work
with bare MDIO nodes without a compatible.

Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
---

(no changes since v1)

 drivers/net/ethernet/xilinx/Kconfig           |   1 +
 drivers/net/ethernet/xilinx/xilinx_axienet.h  |   4 +-
 .../net/ethernet/xilinx/xilinx_axienet_main.c | 104 ++++--------------
 drivers/net/pcs/Kconfig                       |   1 -
 4 files changed, 22 insertions(+), 88 deletions(-)

diff --git a/drivers/net/ethernet/xilinx/Kconfig b/drivers/net/ethernet/xilinx/Kconfig
index 7502214cc7d5..2eab64cf1646 100644
--- a/drivers/net/ethernet/xilinx/Kconfig
+++ b/drivers/net/ethernet/xilinx/Kconfig
@@ -27,6 +27,7 @@ config XILINX_AXI_EMAC
 	tristate "Xilinx 10/100/1000 AXI Ethernet support"
 	depends on HAS_IOMEM
 	depends on XILINX_DMA
+	select OF_DYNAMIC if PCS_XILINX
 	select PHYLINK
 	select DIMLIB
 	help
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h
index 5ff742103beb..f46e862245eb 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet.h
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h
@@ -473,7 +473,6 @@ struct skbuf_dma_descriptor {
  * @dev:	Pointer to device structure
  * @phylink:	Pointer to phylink instance
  * @phylink_config: phylink configuration settings
- * @pcs_phy:	Reference to PCS/PMA PHY if used
  * @pcs:	phylink pcs structure for PCS PHY
  * @switch_x_sgmii: Whether switchable 1000BaseX/SGMII mode is enabled in the core
  * @axi_clk:	AXI4-Lite bus clock
@@ -553,8 +552,7 @@ struct axienet_local {
 	struct phylink *phylink;
 	struct phylink_config phylink_config;
 
-	struct mdio_device *pcs_phy;
-	struct phylink_pcs pcs;
+	struct phylink_pcs *pcs;
 
 	bool switch_x_sgmii;
 
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 054abf283ab3..07487c4b2141 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -35,6 +35,8 @@
 #include <linux/platform_device.h>
 #include <linux/skbuff.h>
 #include <linux/math64.h>
+#include <linux/pcs.h>
+#include <linux/pcs-xilinx.h>
 #include <linux/phy.h>
 #include <linux/mii.h>
 #include <linux/ethtool.h>
@@ -2519,63 +2521,6 @@ static const struct ethtool_ops axienet_ethtool_ops = {
 	.get_rmon_stats = axienet_ethtool_get_rmon_stats,
 };
 
-static struct axienet_local *pcs_to_axienet_local(struct phylink_pcs *pcs)
-{
-	return container_of(pcs, struct axienet_local, pcs);
-}
-
-static void axienet_pcs_get_state(struct phylink_pcs *pcs,
-				  unsigned int neg_mode,
-				  struct phylink_link_state *state)
-{
-	struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
-
-	phylink_mii_c22_pcs_get_state(pcs_phy, neg_mode, state);
-}
-
-static void axienet_pcs_an_restart(struct phylink_pcs *pcs)
-{
-	struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
-
-	phylink_mii_c22_pcs_an_restart(pcs_phy);
-}
-
-static int axienet_pcs_config(struct phylink_pcs *pcs, unsigned int neg_mode,
-			      phy_interface_t interface,
-			      const unsigned long *advertising,
-			      bool permit_pause_to_mac)
-{
-	struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
-	struct net_device *ndev = pcs_to_axienet_local(pcs)->ndev;
-	struct axienet_local *lp = netdev_priv(ndev);
-	int ret;
-
-	if (lp->switch_x_sgmii) {
-		ret = mdiodev_write(pcs_phy, XLNX_MII_STD_SELECT_REG,
-				    interface == PHY_INTERFACE_MODE_SGMII ?
-					XLNX_MII_STD_SELECT_SGMII : 0);
-		if (ret < 0) {
-			netdev_warn(ndev,
-				    "Failed to switch PHY interface: %d\n",
-				    ret);
-			return ret;
-		}
-	}
-
-	ret = phylink_mii_c22_pcs_config(pcs_phy, interface, advertising,
-					 neg_mode);
-	if (ret < 0)
-		netdev_warn(ndev, "Failed to configure PCS: %d\n", ret);
-
-	return ret;
-}
-
-static const struct phylink_pcs_ops axienet_pcs_ops = {
-	.pcs_get_state = axienet_pcs_get_state,
-	.pcs_config = axienet_pcs_config,
-	.pcs_an_restart = axienet_pcs_an_restart,
-};
-
 static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config *config,
 						  phy_interface_t interface)
 {
@@ -2583,8 +2528,8 @@ static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config *config,
 	struct axienet_local *lp = netdev_priv(ndev);
 
 	if (interface == PHY_INTERFACE_MODE_1000BASEX ||
-	    interface ==  PHY_INTERFACE_MODE_SGMII)
-		return &lp->pcs;
+	    interface == PHY_INTERFACE_MODE_SGMII)
+		return lp->pcs;
 
 	return NULL;
 }
@@ -3056,28 +3001,23 @@ static int axienet_probe(struct platform_device *pdev)
 
 	if (lp->phy_mode == PHY_INTERFACE_MODE_SGMII ||
 	    lp->phy_mode == PHY_INTERFACE_MODE_1000BASEX) {
-		np = of_parse_phandle(pdev->dev.of_node, "pcs-handle", 0);
-		if (!np) {
-			/* Deprecated: Always use "pcs-handle" for pcs_phy.
-			 * Falling back to "phy-handle" here is only for
-			 * backward compatibility with old device trees.
-			 */
-			np = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
-		}
-		if (!np) {
-			dev_err(&pdev->dev, "pcs-handle (preferred) or phy-handle required for 1000BaseX/SGMII\n");
-			ret = -EINVAL;
-			goto cleanup_mdio;
-		}
-		lp->pcs_phy = of_mdio_find_device(np);
-		if (!lp->pcs_phy) {
-			ret = -EPROBE_DEFER;
-			of_node_put(np);
+		DECLARE_PHY_INTERFACE_MASK(interfaces);
+
+		phy_interface_zero(interfaces);
+		if (lp->switch_x_sgmii ||
+		    lp->phy_mode == PHY_INTERFACE_MODE_SGMII)
+			__set_bit(PHY_INTERFACE_MODE_SGMII, interfaces);
+		if (lp->switch_x_sgmii ||
+		    lp->phy_mode == PHY_INTERFACE_MODE_1000BASEX)
+			__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
+
+		lp->pcs = axienet_xilinx_pcs_get(&pdev->dev, interfaces);
+		if (IS_ERR(lp->pcs)) {
+			ret = PTR_ERR(lp->pcs);
+			dev_err_probe(&pdev->dev, ret,
+				      "could not get PCS for 1000BASE-X/SGMII\n");
 			goto cleanup_mdio;
 		}
-		of_node_put(np);
-		lp->pcs.ops = &axienet_pcs_ops;
-		lp->pcs.poll = true;
 	}
 
 	lp->phylink_config.dev = &ndev->dev;
@@ -3115,8 +3055,6 @@ static int axienet_probe(struct platform_device *pdev)
 	phylink_destroy(lp->phylink);
 
 cleanup_mdio:
-	if (lp->pcs_phy)
-		put_device(&lp->pcs_phy->dev);
 	if (lp->mii_bus)
 		axienet_mdio_teardown(lp);
 cleanup_clk:
@@ -3139,9 +3077,7 @@ static void axienet_remove(struct platform_device *pdev)
 	if (lp->phylink)
 		phylink_destroy(lp->phylink);
 
-	if (lp->pcs_phy)
-		put_device(&lp->pcs_phy->dev);
-
+	pcs_put(&pdev->dev, lp->pcs);
 	axienet_mdio_teardown(lp);
 
 	clk_bulk_disable_unprepare(XAE_NUM_MISC_CLOCKS, lp->misc_clks);
diff --git a/drivers/net/pcs/Kconfig b/drivers/net/pcs/Kconfig
index 261d2fd29fc7..90ca0002600b 100644
--- a/drivers/net/pcs/Kconfig
+++ b/drivers/net/pcs/Kconfig
@@ -57,7 +57,6 @@ config PCS_XILINX
 	depends on PCS
 	select MDIO_DEVICE
 	select PHYLINK
-	default XILINX_AXI_EMAC
 	tristate "Xilinx PCS driver"
 	help
 	  PCS driver for the Xilinx 1G/2.5G Ethernet PCS/PMA or SGMII device.
-- 
2.35.1.1320.gc452695387.dirty

RE: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem

[Gupta, Suraj]

[AMD Official Use Only - AMD Internal Distribution Only]

> -----Original Message-----
> From: Sean Anderson <sean.anderson@linux.dev>
> Sent: Tuesday, April 8, 2025 4:51 AM
> To: netdev@vger.kernel.org; Andrew Lunn <andrew+netdev@lunn.ch>; David S .
> Miller <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub
> Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Russell King
> <linux@armlinux.org.uk>
> Cc: Heiner Kallweit <hkallweit1@gmail.com>; upstream@airoha.com; Kory
> Maincent <kory.maincent@bootlin.com>; Christian Marangi
> <ansuelsmth@gmail.com>; linux-kernel@vger.kernel.org; Simek, Michal
> <michal.simek@amd.com>; Pandey, Radhey Shyam
> <radhey.shyam.pandey@amd.com>; Robert Hancock
> <robert.hancock@calian.com>; linux-arm-kernel@lists.infradead.org; Sean
> Anderson <sean.anderson@linux.dev>
> Subject: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem
>
> Caution: This message originated from an External Source. Use proper caution
> when opening attachments, clicking links, or responding.
>
>
> Convert the AXI Ethernet driver to use the PCS subsystem, including the new Xilinx
> PCA/PMA driver. Unfortunately, we must use a helper to work with bare MDIO
> nodes without a compatible.
>

AXI ethernet changes looks fine to me, except one minor nit mentioned below. Using DT changesets for backward compatibility is impressive :)
I'll try reviewing pcs/pma patch also and test it with our setups.
> Signed-off-by: Sean Anderson <sean.anderson@linux.dev>

Reviewed-by: Suraj Gupta <suraj.gupta2@amd.com>
> ---
>
> (no changes since v1)
>
>  drivers/net/ethernet/xilinx/Kconfig           |   1 +
>  drivers/net/ethernet/xilinx/xilinx_axienet.h  |   4 +-
>  .../net/ethernet/xilinx/xilinx_axienet_main.c | 104 ++++--------------
>  drivers/net/pcs/Kconfig                       |   1 -
>  4 files changed, 22 insertions(+), 88 deletions(-)
>
> diff --git a/drivers/net/ethernet/xilinx/Kconfig b/drivers/net/ethernet/xilinx/Kconfig
> index 7502214cc7d5..2eab64cf1646 100644
> --- a/drivers/net/ethernet/xilinx/Kconfig
> +++ b/drivers/net/ethernet/xilinx/Kconfig
> @@ -27,6 +27,7 @@ config XILINX_AXI_EMAC
>         tristate "Xilinx 10/100/1000 AXI Ethernet support"
>         depends on HAS_IOMEM
>         depends on XILINX_DMA
> +       select OF_DYNAMIC if PCS_XILINX
>         select PHYLINK
>         select DIMLIB
>         help
> diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h
> b/drivers/net/ethernet/xilinx/xilinx_axienet.h
> index 5ff742103beb..f46e862245eb 100644
> --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h
> +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h
> @@ -473,7 +473,6 @@ struct skbuf_dma_descriptor {
>   * @dev:       Pointer to device structure
>   * @phylink:   Pointer to phylink instance
>   * @phylink_config: phylink configuration settings
> - * @pcs_phy:   Reference to PCS/PMA PHY if used
>   * @pcs:       phylink pcs structure for PCS PHY
>   * @switch_x_sgmii: Whether switchable 1000BaseX/SGMII mode is enabled in
> the core
>   * @axi_clk:   AXI4-Lite bus clock
> @@ -553,8 +552,7 @@ struct axienet_local {
>         struct phylink *phylink;
>         struct phylink_config phylink_config;
>
> -       struct mdio_device *pcs_phy;
> -       struct phylink_pcs pcs;
> +       struct phylink_pcs *pcs;
>
>         bool switch_x_sgmii;
>
> diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
> b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
> index 054abf283ab3..07487c4b2141 100644
> --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
> +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
> @@ -35,6 +35,8 @@
>  #include <linux/platform_device.h>
>  #include <linux/skbuff.h>
>  #include <linux/math64.h>
> +#include <linux/pcs.h>
> +#include <linux/pcs-xilinx.h>
>  #include <linux/phy.h>
>  #include <linux/mii.h>
>  #include <linux/ethtool.h>
> @@ -2519,63 +2521,6 @@ static const struct ethtool_ops axienet_ethtool_ops = {
>         .get_rmon_stats = axienet_ethtool_get_rmon_stats,  };
>
> -static struct axienet_local *pcs_to_axienet_local(struct phylink_pcs *pcs) -{
> -       return container_of(pcs, struct axienet_local, pcs);
> -}
> -
> -static void axienet_pcs_get_state(struct phylink_pcs *pcs,
> -                                 unsigned int neg_mode,
> -                                 struct phylink_link_state *state)
> -{
> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
> -
> -       phylink_mii_c22_pcs_get_state(pcs_phy, neg_mode, state);
> -}
> -
> -static void axienet_pcs_an_restart(struct phylink_pcs *pcs) -{
> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
> -
> -       phylink_mii_c22_pcs_an_restart(pcs_phy);
> -}
> -
> -static int axienet_pcs_config(struct phylink_pcs *pcs, unsigned int neg_mode,
> -                             phy_interface_t interface,
> -                             const unsigned long *advertising,
> -                             bool permit_pause_to_mac)
> -{
> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
> -       struct net_device *ndev = pcs_to_axienet_local(pcs)->ndev;
> -       struct axienet_local *lp = netdev_priv(ndev);
> -       int ret;
> -
> -       if (lp->switch_x_sgmii) {
> -               ret = mdiodev_write(pcs_phy, XLNX_MII_STD_SELECT_REG,
> -                                   interface == PHY_INTERFACE_MODE_SGMII ?
> -                                       XLNX_MII_STD_SELECT_SGMII : 0);
> -               if (ret < 0) {
> -                       netdev_warn(ndev,
> -                                   "Failed to switch PHY interface: %d\n",
> -                                   ret);
> -                       return ret;
> -               }
> -       }
> -
> -       ret = phylink_mii_c22_pcs_config(pcs_phy, interface, advertising,
> -                                        neg_mode);
> -       if (ret < 0)
> -               netdev_warn(ndev, "Failed to configure PCS: %d\n", ret);
> -
> -       return ret;
> -}
> -
> -static const struct phylink_pcs_ops axienet_pcs_ops = {
> -       .pcs_get_state = axienet_pcs_get_state,
> -       .pcs_config = axienet_pcs_config,
> -       .pcs_an_restart = axienet_pcs_an_restart,
> -};
> -
>  static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config *config,
>                                                   phy_interface_t interface)  { @@ -2583,8 +2528,8
> @@ static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config
> *config,
>         struct axienet_local *lp = netdev_priv(ndev);
>
>         if (interface == PHY_INTERFACE_MODE_1000BASEX ||
> -           interface ==  PHY_INTERFACE_MODE_SGMII)
> -               return &lp->pcs;
> +           interface == PHY_INTERFACE_MODE_SGMII)

nit: unchanged check.

> +               return lp->pcs;
>
>         return NULL;
>  }
> @@ -3056,28 +3001,23 @@ static int axienet_probe(struct platform_device *pdev)
>
>         if (lp->phy_mode == PHY_INTERFACE_MODE_SGMII ||
>             lp->phy_mode == PHY_INTERFACE_MODE_1000BASEX) {
> -               np = of_parse_phandle(pdev->dev.of_node, "pcs-handle", 0);
> -               if (!np) {
> -                       /* Deprecated: Always use "pcs-handle" for pcs_phy.
> -                        * Falling back to "phy-handle" here is only for
> -                        * backward compatibility with old device trees.
> -                        */
> -                       np = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
> -               }
> -               if (!np) {
> -                       dev_err(&pdev->dev, "pcs-handle (preferred) or phy-handle required
> for 1000BaseX/SGMII\n");
> -                       ret = -EINVAL;
> -                       goto cleanup_mdio;
> -               }
> -               lp->pcs_phy = of_mdio_find_device(np);
> -               if (!lp->pcs_phy) {
> -                       ret = -EPROBE_DEFER;
> -                       of_node_put(np);
> +               DECLARE_PHY_INTERFACE_MASK(interfaces);
> +
> +               phy_interface_zero(interfaces);
> +               if (lp->switch_x_sgmii ||
> +                   lp->phy_mode == PHY_INTERFACE_MODE_SGMII)
> +                       __set_bit(PHY_INTERFACE_MODE_SGMII, interfaces);
> +               if (lp->switch_x_sgmii ||
> +                   lp->phy_mode == PHY_INTERFACE_MODE_1000BASEX)
> +                       __set_bit(PHY_INTERFACE_MODE_1000BASEX,
> + interfaces);
> +
> +               lp->pcs = axienet_xilinx_pcs_get(&pdev->dev, interfaces);
> +               if (IS_ERR(lp->pcs)) {
> +                       ret = PTR_ERR(lp->pcs);
> +                       dev_err_probe(&pdev->dev, ret,
> +                                     "could not get PCS for
> + 1000BASE-X/SGMII\n");
>                         goto cleanup_mdio;
>                 }
> -               of_node_put(np);
> -               lp->pcs.ops = &axienet_pcs_ops;
> -               lp->pcs.poll = true;
>         }
>
>         lp->phylink_config.dev = &ndev->dev; @@ -3115,8 +3055,6 @@ static int
> axienet_probe(struct platform_device *pdev)
>         phylink_destroy(lp->phylink);
>
>  cleanup_mdio:
> -       if (lp->pcs_phy)
> -               put_device(&lp->pcs_phy->dev);
>         if (lp->mii_bus)
>                 axienet_mdio_teardown(lp);
>  cleanup_clk:
> @@ -3139,9 +3077,7 @@ static void axienet_remove(struct platform_device
> *pdev)
>         if (lp->phylink)
>                 phylink_destroy(lp->phylink);
>
> -       if (lp->pcs_phy)
> -               put_device(&lp->pcs_phy->dev);
> -
> +       pcs_put(&pdev->dev, lp->pcs);
>         axienet_mdio_teardown(lp);
>
>         clk_bulk_disable_unprepare(XAE_NUM_MISC_CLOCKS, lp->misc_clks); diff
> --git a/drivers/net/pcs/Kconfig b/drivers/net/pcs/Kconfig index
> 261d2fd29fc7..90ca0002600b 100644
> --- a/drivers/net/pcs/Kconfig
> +++ b/drivers/net/pcs/Kconfig
> @@ -57,7 +57,6 @@ config PCS_XILINX
>         depends on PCS
>         select MDIO_DEVICE
>         select PHYLINK
> -       default XILINX_AXI_EMAC
>         tristate "Xilinx PCS driver"
>         help
>           PCS driver for the Xilinx 1G/2.5G Ethernet PCS/PMA or SGMII device.
> --
> 2.35.1.1320.gc452695387.dirty
>

Re: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem

[Sean Anderson]

On 4/8/25 08:19, Gupta, Suraj wrote:
> [AMD Official Use Only - AMD Internal Distribution Only]
> 
>> -----Original Message-----
>> From: Sean Anderson <sean.anderson@linux.dev>
>> Sent: Tuesday, April 8, 2025 4:51 AM
>> To: netdev@vger.kernel.org; Andrew Lunn <andrew+netdev@lunn.ch>; David S .
>> Miller <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub
>> Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Russell King
>> <linux@armlinux.org.uk>
>> Cc: Heiner Kallweit <hkallweit1@gmail.com>; upstream@airoha.com; Kory
>> Maincent <kory.maincent@bootlin.com>; Christian Marangi
>> <ansuelsmth@gmail.com>; linux-kernel@vger.kernel.org; Simek, Michal
>> <michal.simek@amd.com>; Pandey, Radhey Shyam
>> <radhey.shyam.pandey@amd.com>; Robert Hancock
>> <robert.hancock@calian.com>; linux-arm-kernel@lists.infradead.org; Sean
>> Anderson <sean.anderson@linux.dev>
>> Subject: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem
>>
>> Caution: This message originated from an External Source. Use proper caution
>> when opening attachments, clicking links, or responding.
>>
>>
>> Convert the AXI Ethernet driver to use the PCS subsystem, including the new Xilinx
>> PCA/PMA driver. Unfortunately, we must use a helper to work with bare MDIO
>> nodes without a compatible.
>>
> 
> AXI ethernet changes looks fine to me, except one minor nit mentioned below. Using DT changesets for backward compatibility is impressive :)
> I'll try reviewing pcs/pma patch also and test it with our setups.
>> Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
> 
> Reviewed-by: Suraj Gupta <suraj.gupta2@amd.com>
>> ---
>>
>> (no changes since v1)
>>
>>  drivers/net/ethernet/xilinx/Kconfig           |   1 +
>>  drivers/net/ethernet/xilinx/xilinx_axienet.h  |   4 +-
>>  .../net/ethernet/xilinx/xilinx_axienet_main.c | 104 ++++--------------
>>  drivers/net/pcs/Kconfig                       |   1 -
>>  4 files changed, 22 insertions(+), 88 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/xilinx/Kconfig b/drivers/net/ethernet/xilinx/Kconfig
>> index 7502214cc7d5..2eab64cf1646 100644
>> --- a/drivers/net/ethernet/xilinx/Kconfig
>> +++ b/drivers/net/ethernet/xilinx/Kconfig
>> @@ -27,6 +27,7 @@ config XILINX_AXI_EMAC
>>         tristate "Xilinx 10/100/1000 AXI Ethernet support"
>>         depends on HAS_IOMEM
>>         depends on XILINX_DMA
>> +       select OF_DYNAMIC if PCS_XILINX
>>         select PHYLINK
>>         select DIMLIB
>>         help
>> diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h
>> b/drivers/net/ethernet/xilinx/xilinx_axienet.h
>> index 5ff742103beb..f46e862245eb 100644
>> --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h
>> +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h
>> @@ -473,7 +473,6 @@ struct skbuf_dma_descriptor {
>>   * @dev:       Pointer to device structure
>>   * @phylink:   Pointer to phylink instance
>>   * @phylink_config: phylink configuration settings
>> - * @pcs_phy:   Reference to PCS/PMA PHY if used
>>   * @pcs:       phylink pcs structure for PCS PHY
>>   * @switch_x_sgmii: Whether switchable 1000BaseX/SGMII mode is enabled in
>> the core
>>   * @axi_clk:   AXI4-Lite bus clock
>> @@ -553,8 +552,7 @@ struct axienet_local {
>>         struct phylink *phylink;
>>         struct phylink_config phylink_config;
>>
>> -       struct mdio_device *pcs_phy;
>> -       struct phylink_pcs pcs;
>> +       struct phylink_pcs *pcs;
>>
>>         bool switch_x_sgmii;
>>
>> diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
>> b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
>> index 054abf283ab3..07487c4b2141 100644
>> --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
>> +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
>> @@ -35,6 +35,8 @@
>>  #include <linux/platform_device.h>
>>  #include <linux/skbuff.h>
>>  #include <linux/math64.h>
>> +#include <linux/pcs.h>
>> +#include <linux/pcs-xilinx.h>
>>  #include <linux/phy.h>
>>  #include <linux/mii.h>
>>  #include <linux/ethtool.h>
>> @@ -2519,63 +2521,6 @@ static const struct ethtool_ops axienet_ethtool_ops = {
>>         .get_rmon_stats = axienet_ethtool_get_rmon_stats,  };
>>
>> -static struct axienet_local *pcs_to_axienet_local(struct phylink_pcs *pcs) -{
>> -       return container_of(pcs, struct axienet_local, pcs);
>> -}
>> -
>> -static void axienet_pcs_get_state(struct phylink_pcs *pcs,
>> -                                 unsigned int neg_mode,
>> -                                 struct phylink_link_state *state)
>> -{
>> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
>> -
>> -       phylink_mii_c22_pcs_get_state(pcs_phy, neg_mode, state);
>> -}
>> -
>> -static void axienet_pcs_an_restart(struct phylink_pcs *pcs) -{
>> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
>> -
>> -       phylink_mii_c22_pcs_an_restart(pcs_phy);
>> -}
>> -
>> -static int axienet_pcs_config(struct phylink_pcs *pcs, unsigned int neg_mode,
>> -                             phy_interface_t interface,
>> -                             const unsigned long *advertising,
>> -                             bool permit_pause_to_mac)
>> -{
>> -       struct mdio_device *pcs_phy = pcs_to_axienet_local(pcs)->pcs_phy;
>> -       struct net_device *ndev = pcs_to_axienet_local(pcs)->ndev;
>> -       struct axienet_local *lp = netdev_priv(ndev);
>> -       int ret;
>> -
>> -       if (lp->switch_x_sgmii) {
>> -               ret = mdiodev_write(pcs_phy, XLNX_MII_STD_SELECT_REG,
>> -                                   interface == PHY_INTERFACE_MODE_SGMII ?
>> -                                       XLNX_MII_STD_SELECT_SGMII : 0);
>> -               if (ret < 0) {
>> -                       netdev_warn(ndev,
>> -                                   "Failed to switch PHY interface: %d\n",
>> -                                   ret);
>> -                       return ret;
>> -               }
>> -       }
>> -
>> -       ret = phylink_mii_c22_pcs_config(pcs_phy, interface, advertising,
>> -                                        neg_mode);
>> -       if (ret < 0)
>> -               netdev_warn(ndev, "Failed to configure PCS: %d\n", ret);
>> -
>> -       return ret;
>> -}
>> -
>> -static const struct phylink_pcs_ops axienet_pcs_ops = {
>> -       .pcs_get_state = axienet_pcs_get_state,
>> -       .pcs_config = axienet_pcs_config,
>> -       .pcs_an_restart = axienet_pcs_an_restart,
>> -};
>> -
>>  static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config *config,
>>                                                   phy_interface_t interface)  { @@ -2583,8 +2528,8
>> @@ static struct phylink_pcs *axienet_mac_select_pcs(struct phylink_config
>> *config,
>>         struct axienet_local *lp = netdev_priv(ndev);
>>
>>         if (interface == PHY_INTERFACE_MODE_1000BASEX ||
>> -           interface ==  PHY_INTERFACE_MODE_SGMII)
>> -               return &lp->pcs;
>> +           interface == PHY_INTERFACE_MODE_SGMII)
> 
> nit: unchanged check.

Just fixing up the spacing while I was "in the area"

--Sean

Re: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem

[kernel test robot]

Hi Sean,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Sean-Anderson/dt-bindings-net-Add-Xilinx-PCS/20250408-072650
base:   net-next/main
patch link:    https://lore.kernel.org/r/20250407232058.2317056-1-sean.anderson%40linux.dev
patch subject: [net-next PATCH v2 11/14] net: axienet: Convert to use PCS subsystem
config: arm-randconfig-001-20250409 (https://download.01.org/0day-ci/archive/20250409/202504091007.RSwPrfcI-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250409/202504091007.RSwPrfcI-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202504091007.RSwPrfcI-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/net/ethernet/xilinx/xilinx_axienet_main.c:38:0:
   include/linux/pcs.h: In function 'pcs_get':
>> include/linux/pcs.h:165:9: warning: return makes pointer from integer without a cast [-Wint-conversion]
     return -EOPNOTSUPP;
            ^
   include/linux/pcs.h: In function 'pcs_get_by_fwnode':
   include/linux/pcs.h:178:9: warning: return makes pointer from integer without a cast [-Wint-conversion]
     return -EOPNOTSUPP;
            ^
   include/linux/pcs.h: In function 'pcs_get_by_dev':
   include/linux/pcs.h:191:9: warning: return makes pointer from integer without a cast [-Wint-conversion]
     return -EOPNOTSUPP;
            ^


vim +165 include/linux/pcs.h

b7da98b4ee6f2f Sean Anderson 2025-04-07  162  
b7da98b4ee6f2f Sean Anderson 2025-04-07  163  static inline struct phylink_pcs *pcs_get(struct device *dev, const char *id)
b7da98b4ee6f2f Sean Anderson 2025-04-07  164  {
b7da98b4ee6f2f Sean Anderson 2025-04-07 @165  	return -EOPNOTSUPP;
b7da98b4ee6f2f Sean Anderson 2025-04-07  166  }
b7da98b4ee6f2f Sean Anderson 2025-04-07  167  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [net-next PATCH v2 00/14] Add PCS core support

[Jakub Kicinski]

On Mon,  7 Apr 2025 19:17:31 -0400 Sean Anderson wrote:
> This series depends on [1,2], and they have been included at the
> beginning so CI will run. However, I expect them to be reviewed/applied
> outside the net-next tree.

These appear to break the build:

drivers/acpi/property.c:1669:39: error: initialization of ‘int (*)(const struct fwnode_handle *, const char *, const char *, int,  unsigned int,  struct fwnode_reference_args *)’ from incompatible pointer type ‘int (*)(const struct fwnode_handle *, const char *, const char *, unsigned int,  unsigned int,  struct fwnode_reference_args *)’ [-Wincompatible-pointer-types]
 1669 |                 .get_reference_args = acpi_fwnode_get_reference_args,   \

Could you post as RFC until we can actually merge this? I'm worried 
some sleep deprived maintainer may miss the note in the cover letter
and just apply it all to net-next..
-- 
pw-bot: cr

Re: [net-next PATCH v2 00/14] Add PCS core support

[Sean Anderson]

On 4/8/25 10:50, Jakub Kicinski wrote:
> On Mon,  7 Apr 2025 19:17:31 -0400 Sean Anderson wrote:
>> This series depends on [1,2], and they have been included at the
>> beginning so CI will run. However, I expect them to be reviewed/applied
>> outside the net-next tree.
> 
> These appear to break the build:
> 
> drivers/acpi/property.c:1669:39: error: initialization of ‘int (*)(const struct fwnode_handle *, const char *, const char *, int,  unsigned int,  struct fwnode_reference_args *)’ from incompatible pointer type ‘int (*)(const struct fwnode_handle *, const char *, const char *, unsigned int,  unsigned int,  struct fwnode_reference_args *)’ [-Wincompatible-pointer-types]
>  1669 |                 .get_reference_args = acpi_fwnode_get_reference_args,   \
> 
> Could you post as RFC until we can actually merge this? I'm worried 
> some sleep deprived maintainer may miss the note in the cover letter
> and just apply it all to net-next..

I would really like to keep RFC off the titles since some reviewers don't
pay attention to RFC series.

Would [DO NOT MERGE] in the subject be OK?

--Sean

Re: [net-next PATCH v2 00/14] Add PCS core support

[Jakub Kicinski]

On Tue, 8 Apr 2025 11:30:43 -0400 Sean Anderson wrote:
> > These appear to break the build:
> > 
> > drivers/acpi/property.c:1669:39: error: initialization of ‘int (*)(const struct fwnode_handle *, const char *, const char *, int,  unsigned int,  struct fwnode_reference_args *)’ from incompatible pointer type ‘int (*)(const struct fwnode_handle *, const char *, const char *, unsigned int,  unsigned int,  struct fwnode_reference_args *)’ [-Wincompatible-pointer-types]
> >  1669 |                 .get_reference_args = acpi_fwnode_get_reference_args,   \
> > 
> > Could you post as RFC until we can actually merge this? I'm worried 
> > some sleep deprived maintainer may miss the note in the cover letter
> > and just apply it all to net-next..  
> 
> I would really like to keep RFC off the titles since some reviewers don't
> pay attention to RFC series.
> 
> Would [DO NOT MERGE] in the subject be OK?

That works too.

Re: [net-next PATCH v2 00/14] Add PCS core support

[Russell King (Oracle)]

On Tue, Apr 08, 2025 at 11:30:43AM -0400, Sean Anderson wrote:
> On 4/8/25 10:50, Jakub Kicinski wrote:
> > On Mon,  7 Apr 2025 19:17:31 -0400 Sean Anderson wrote:
> >> This series depends on [1,2], and they have been included at the
> >> beginning so CI will run. However, I expect them to be reviewed/applied
> >> outside the net-next tree.
> > 
> > These appear to break the build:
> > 
> > drivers/acpi/property.c:1669:39: error: initialization of ‘int (*)(const struct fwnode_handle *, const char *, const char *, int,  unsigned int,  struct fwnode_reference_args *)’ from incompatible pointer type ‘int (*)(const struct fwnode_handle *, const char *, const char *, unsigned int,  unsigned int,  struct fwnode_reference_args *)’ [-Wincompatible-pointer-types]
> >  1669 |                 .get_reference_args = acpi_fwnode_get_reference_args,   \
> > 
> > Could you post as RFC until we can actually merge this? I'm worried 
> > some sleep deprived maintainer may miss the note in the cover letter
> > and just apply it all to net-next..
> 
> I would really like to keep RFC off the titles since some reviewers don't
> pay attention to RFC series.
> 
> Would [DO NOT MERGE] in the subject be OK?

I'd bet that those who have decided "RFC means the patch series is not
ready" will take such a notice to also mean the same, and ignore it.

I think there needs to be some kind of push-back against these
maintainers who explicitly state that they ignore RFC series - making
it basically anti-social behaviour in the kernel community.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!