701-net-0283-net-dsa-felix-Add-PCS-operations-for-PHYLINK.patch

From 0e219a6aa07754d81a25c9e4408d81d194cd2000 Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Fri, 22 Nov 2019 13:45:52 +0200
Subject: [PATCH] net: dsa: felix: Add PCS operations for PHYLINK

This removes the bootloader dependency for SGMII PCS pre-configuration,
as well as adds support for monitoring the in-band SGMII AN between the
PCS and the system-side link partner (PHY or other MAC).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/dsa/ocelot/felix.c         |  23 ++-
 drivers/net/dsa/ocelot/felix.h         |   7 +-
 drivers/net/dsa/ocelot/felix_vsc9959.c | 292 ++++++++++++++++++++++++++++++++-
 3 files changed, 314 insertions(+), 8 deletions(-)

--- a/drivers/net/dsa/ocelot/felix.c
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -265,7 +265,7 @@ static int felix_get_ts_info(struct dsa_
 static int felix_init_structs(struct felix *felix, int num_phys_ports)
 {
 	struct ocelot *ocelot = &felix->ocelot;
-	resource_size_t base;
+	resource_size_t switch_base;
 	int port, i, err;
 
 	ocelot->num_phys_ports = num_phys_ports;
@@ -281,7 +281,8 @@ static int felix_init_structs(struct fel
 	ocelot->ops		= felix->info->ops;
 	ocelot->quirks		= felix->info->quirks;
 
-	base = pci_resource_start(felix->pdev, felix->info->pci_bar);
+	switch_base = pci_resource_start(felix->pdev,
+					 felix->info->switch_pci_bar);
 
 	for (i = 0; i < TARGET_MAX; i++) {
 		struct regmap *target;
@@ -292,8 +293,8 @@ static int felix_init_structs(struct fel
 
 		res = &felix->info->target_io_res[i];
 		res->flags = IORESOURCE_MEM;
-		res->start += base;
-		res->end += base;
+		res->start += switch_base;
+		res->end += switch_base;
 
 		target = ocelot_regmap_init(ocelot, res);
 		if (IS_ERR(target)) {
@@ -327,8 +328,8 @@ static int felix_init_structs(struct fel
 
 		res = &felix->info->port_io_res[port];
 		res->flags = IORESOURCE_MEM;
-		res->start += base;
-		res->end += base;
+		res->start += switch_base;
+		res->end += switch_base;
 
 		port_regs = devm_ioremap_resource(ocelot->dev, res);
 		if (IS_ERR(port_regs)) {
@@ -342,6 +343,12 @@ static int felix_init_structs(struct fel
 		ocelot->ports[port] = ocelot_port;
 	}
 
+	if (felix->info->mdio_bus_alloc) {
+		err = felix->info->mdio_bus_alloc(ocelot);
+		if (err < 0)
+			return err;
+	}
+
 	return 0;
 }
 
@@ -377,6 +384,10 @@ static int felix_setup(struct dsa_switch
 static void felix_teardown(struct dsa_switch *ds)
 {
 	struct ocelot *ocelot = ds->priv;
+	struct felix *felix = ocelot_to_felix(ocelot);
+
+	if (felix->imdio)
+		mdiobus_unregister(felix->imdio);
 
 	/* stop workqueue thread */
 	ocelot_deinit(ocelot);
--- a/drivers/net/dsa/ocelot/felix.h
+++ b/drivers/net/dsa/ocelot/felix.h
@@ -10,6 +10,7 @@
 struct felix_info {
 	struct resource			*target_io_res;
 	struct resource			*port_io_res;
+	struct resource			*imdio_res;
 	const struct reg_field		*regfields;
 	const u32 *const		*map;
 	const struct ocelot_ops		*ops;
@@ -17,8 +18,10 @@ struct felix_info {
 	const struct ocelot_stat_layout	*stats_layout;
 	unsigned int			num_stats;
 	int				num_ports;
-	int				pci_bar;
+	int				switch_pci_bar;
+	int				imdio_pci_bar;
 	unsigned long			quirks;
+	int (*mdio_bus_alloc)(struct ocelot *ocelot);
 };
 
 extern struct felix_info		felix_info_vsc9959;
@@ -33,6 +36,8 @@ struct felix {
 	struct pci_dev			*pdev;
 	struct felix_info		*info;
 	struct ocelot			ocelot;
+	struct mii_bus			*imdio;
+	struct phy_device		**pcs;
 };
 
 #endif
--- a/drivers/net/dsa/ocelot/felix_vsc9959.c
+++ b/drivers/net/dsa/ocelot/felix_vsc9959.c
@@ -2,6 +2,7 @@
 /* Copyright 2017 Microsemi Corporation
  * Copyright 2018-2019 NXP Semiconductors
  */
+#include <linux/fsl/enetc_mdio.h>
 #include <soc/mscc/ocelot_sys.h>
 #include <soc/mscc/ocelot.h>
 #include <linux/iopoll.h>
@@ -390,6 +391,15 @@ static struct resource vsc9959_port_io_r
 	},
 };
 
+/* Port MAC 0 Internal MDIO bus through which the SerDes acting as an
+ * SGMII/QSGMII MAC PCS can be found.
+ */
+static struct resource vsc9959_imdio_res = {
+	.start		= 0x8030,
+	.end		= 0x8040,
+	.name		= "imdio",
+};
+
 static const struct reg_field vsc9959_regfields[] = {
 	[ANA_ADVLEARN_VLAN_CHK] = REG_FIELD(ANA_ADVLEARN, 6, 6),
 	[ANA_ADVLEARN_LEARN_MIRROR] = REG_FIELD(ANA_ADVLEARN, 0, 5),
@@ -569,13 +579,291 @@ static int vsc9959_reset(struct ocelot *
 	return 0;
 }
 
+void vsc9959_pcs_validate(struct ocelot *ocelot, int port,
+			  unsigned long *supported,
+			  struct phylink_link_state *state)
+{
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
+
+	if (state->interface != PHY_INTERFACE_MODE_NA &&
+	    state->interface != PHY_INTERFACE_MODE_GMII &&
+	    state->interface != PHY_INTERFACE_MODE_SGMII &&
+	    state->interface != PHY_INTERFACE_MODE_QSGMII &&
+	    state->interface != PHY_INTERFACE_MODE_USXGMII) {
+		bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
+		return;
+	}
+
+	/* No half-duplex. */
+	phylink_set_port_modes(mask);
+	phylink_set(mask, Autoneg);
+	phylink_set(mask, Pause);
+	phylink_set(mask, Asym_Pause);
+	phylink_set(mask, 10baseT_Full);
+	phylink_set(mask, 100baseT_Full);
+	phylink_set(mask, 1000baseT_Full);
+	phylink_set(mask, 1000baseX_Full);
+	phylink_set(mask, 2500baseT_Full);
+	phylink_set(mask, 2500baseX_Full);
+	phylink_set(mask, 1000baseKX_Full);
+
+	bitmap_and(supported, supported, mask,
+		   __ETHTOOL_LINK_MODE_MASK_NBITS);
+	bitmap_and(state->advertising, state->advertising, mask,
+		   __ETHTOOL_LINK_MODE_MASK_NBITS);
+}
+
+static void vsc9959_pcs_an_restart(struct ocelot *ocelot, int port)
+{
+	struct felix *felix = ocelot_to_felix(ocelot);
+	struct phy_device *pcs = felix->pcs[port];
+
+	if (!pcs)
+		return;
+
+	phy_set_bits(pcs, MII_BMCR, BMCR_ANRESTART);
+}
+
+static void vsc9959_pcs_init_sgmii(struct phy_device *pcs,
+				   unsigned int link_an_mode,
+				   const struct phylink_link_state *state)
+{
+	/* SGMII spec requires tx_config_Reg[15:0] to be exactly 0x4001
+	 * for the MAC PCS in order to acknowledge the AN.
+	 */
+	phy_write(pcs, MII_ADVERTISE, ADVERTISE_SGMII | ADVERTISE_LPACK);
+
+	/* Set to SGMII mode, use AN */
+	phy_write(pcs, ENETC_PCS_IF_MODE, ENETC_PCS_IF_MODE_SGMII_AN);
+
+	/* Adjust link timer for SGMII */
+	phy_write(pcs, ENETC_PCS_LINK_TIMER1, ENETC_PCS_LINK_TIMER1_VAL);
+	phy_write(pcs, ENETC_PCS_LINK_TIMER2, ENETC_PCS_LINK_TIMER2_VAL);
+
+	phy_write(pcs, MII_BMCR, BMCR_SPEED1000 |
+				 BMCR_FULLDPLX |
+				 BMCR_ANENABLE);
+}
+
+#define ADVERTISE_USXGMII_FDX		BIT(12)
+
+static void vsc9959_pcs_init_sxgmii(struct phy_device *pcs,
+				    unsigned int link_an_mode,
+				    const struct phylink_link_state *state)
+{
+	/* Configure device ability for the USXGMII Replicator */
+	phy_write_mmd(pcs, MDIO_MMD_VEND2, MII_ADVERTISE,
+		      ADVERTISE_SGMII |
+		      ADVERTISE_LPACK |
+		      ADVERTISE_USXGMII_FDX);
+}
+
+static void vsc9959_pcs_init(struct ocelot *ocelot, int port,
+			     unsigned int link_an_mode,
+			     const struct phylink_link_state *state)
+{
+	struct felix *felix = ocelot_to_felix(ocelot);
+	struct phy_device *pcs = felix->pcs[port];
+
+	if (!pcs)
+		return;
+
+	if (link_an_mode == MLO_AN_FIXED) {
+		phydev_err(pcs, "Fixed modes are not yet supported.\n");
+		return;
+	}
+
+	pcs->interface = state->interface;
+	if (pcs->interface == PHY_INTERFACE_MODE_USXGMII)
+		pcs->is_c45 = true;
+	else
+		pcs->is_c45 = false;
+
+	/* The PCS does not implement the BMSR register fully, so capability
+	 * detection via genphy_read_abilities does not work. Since we can get
+	 * the PHY config word from the LPA register though, there is still
+	 * value in using the generic phy_resolve_aneg_linkmode function. So
+	 * populate the supported and advertising link modes manually here.
+	 */
+	linkmode_set_bit_array(phy_basic_ports_array,
+			       ARRAY_SIZE(phy_basic_ports_array),
+			       pcs->supported);
+	linkmode_set_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, pcs->supported);
+	linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT, pcs->supported);
+	linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT, pcs->supported);
+	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT, pcs->supported);
+	phy_advertise_supported(pcs);
+
+	switch (pcs->interface) {
+	case PHY_INTERFACE_MODE_SGMII:
+	case PHY_INTERFACE_MODE_QSGMII:
+		vsc9959_pcs_init_sgmii(pcs, link_an_mode, state);
+		break;
+	case PHY_INTERFACE_MODE_USXGMII:
+		vsc9959_pcs_init_sxgmii(pcs, link_an_mode, state);
+		break;
+	default:
+		dev_err(ocelot->dev, "Unsupported link mode %s\n",
+			phy_modes(pcs->interface));
+	}
+}
+
+static void vsc9959_pcs_link_state(struct ocelot *ocelot, int port,
+				   struct phylink_link_state *state)
+{
+	struct felix *felix = ocelot_to_felix(ocelot);
+	struct phy_device *pcs = felix->pcs[port];
+	int err;
+
+	if (!pcs)
+		return;
+
+	/* Reading PCS status not yet supported for USXGMII */
+	if (pcs->is_c45) {
+		state->link = 1;
+		return;
+	}
+
+	pcs->speed = SPEED_UNKNOWN;
+	pcs->duplex = DUPLEX_UNKNOWN;
+	pcs->pause = 0;
+	pcs->asym_pause = 0;
+
+	err = genphy_update_link(pcs);
+	if (err < 0)
+		return;
+
+	if (pcs->autoneg_complete) {
+		u16 lpa = phy_read(pcs, MII_LPA);
+
+		switch (state->interface) {
+		case PHY_INTERFACE_MODE_SGMII:
+		case PHY_INTERFACE_MODE_QSGMII:
+			mii_lpa_to_linkmode_lpa_sgmii(pcs->lp_advertising, lpa);
+			break;
+		default:
+			return;
+		}
+
+		phy_resolve_aneg_linkmode(pcs);
+	}
+
+	state->an_complete = pcs->autoneg_complete;
+	state->an_enabled = pcs->autoneg;
+	state->link = pcs->link;
+	state->duplex = pcs->duplex;
+	state->speed = pcs->speed;
+	/* SGMII AN does not negotiate flow control, but that's ok,
+	 * since phylink already knows that, and does:
+	 *	link_state.pause |= pl->phy_state.pause;
+	 */
+	state->pause = pcs->pause;
+
+	dev_dbg(ocelot->dev,
+		"%s: mode=%s/%s/%s adv=%*pb lpa=%*pb link=%u an_enabled=%u an_complete=%u\n",
+		__func__,
+		phy_modes(state->interface),
+		phy_speed_to_str(state->speed),
+		phy_duplex_to_str(state->duplex),
+		__ETHTOOL_LINK_MODE_MASK_NBITS, state->advertising,
+		__ETHTOOL_LINK_MODE_MASK_NBITS, state->lp_advertising,
+		state->link, state->an_enabled, state->an_complete);
+}
+
 static const struct ocelot_ops vsc9959_ops = {
 	.reset			= vsc9959_reset,
+	.pcs_init		= vsc9959_pcs_init,
+	.pcs_an_restart		= vsc9959_pcs_an_restart,
+	.pcs_link_state		= vsc9959_pcs_link_state,
+	.pcs_validate		= vsc9959_pcs_validate,
 };
 
+static int vsc9959_mdio_bus_alloc(struct ocelot *ocelot)
+{
+	struct felix *felix = ocelot_to_felix(ocelot);
+	struct enetc_mdio_priv *mdio_priv;
+	struct device *dev = ocelot->dev;
+	resource_size_t imdio_base;
+	void __iomem *imdio_regs;
+	struct resource *res;
+	struct enetc_hw *hw;
+	struct mii_bus *bus;
+	int port;
+	int rc;
+
+	felix->pcs = devm_kcalloc(dev, felix->info->num_ports,
+				  sizeof(struct phy_device),
+				  GFP_KERNEL);
+	if (!felix->pcs) {
+		dev_err(dev, "failed to allocate array for PCS PHYs\n");
+		return -ENOMEM;
+	}
+
+	imdio_base = pci_resource_start(felix->pdev,
+					felix->info->imdio_pci_bar);
+
+	res = felix->info->imdio_res;
+	res->flags = IORESOURCE_MEM;
+	res->start += imdio_base;
+	res->end += imdio_base;
+
+	imdio_regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(imdio_regs)) {
+		dev_err(dev, "failed to map internal MDIO registers\n");
+		return PTR_ERR(imdio_regs);
+	}
+
+	hw = enetc_hw_alloc(dev, imdio_regs);
+	if (IS_ERR(hw)) {
+		dev_err(dev, "failed to allocate ENETC HW structure\n");
+		return PTR_ERR(hw);
+	}
+
+	bus = devm_mdiobus_alloc_size(dev, sizeof(*mdio_priv));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "VSC9959 internal MDIO bus";
+	bus->read = enetc_mdio_read;
+	bus->write = enetc_mdio_write;
+	bus->parent = dev;
+	mdio_priv = bus->priv;
+	mdio_priv->hw = hw;
+	/* This gets added to imdio_regs, which already maps addresses
+	 * starting with the proper offset.
+	 */
+	mdio_priv->mdio_base = 0;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-imdio", dev_name(dev));
+
+	/* Needed in order to initialize the bus mutex lock */
+	rc = mdiobus_register(bus);
+	if (rc < 0) {
+		dev_err(dev, "failed to register MDIO bus\n");
+		return rc;
+	}
+
+	felix->imdio = bus;
+
+	for (port = 0; port < felix->info->num_ports; port++) {
+		struct phy_device *pcs;
+		bool is_c45 = false;
+
+		pcs = get_phy_device(felix->imdio, port, is_c45);
+		if (IS_ERR(pcs))
+			continue;
+
+		felix->pcs[port] = pcs;
+
+		dev_info(dev, "Found PCS at internal MDIO address %d\n", port);
+	}
+
+	return 0;
+}
+
 struct felix_info felix_info_vsc9959 = {
 	.target_io_res		= vsc9959_target_io_res,
 	.port_io_res		= vsc9959_port_io_res,
+	.imdio_res		= &vsc9959_imdio_res,
 	.regfields		= vsc9959_regfields,
 	.map			= vsc9959_regmap,
 	.ops			= &vsc9959_ops,
@@ -583,6 +871,8 @@ struct felix_info felix_info_vsc9959 = {
 	.num_stats		= ARRAY_SIZE(vsc9959_stats_layout),
 	.shared_queue_sz	= 128 * 1024,
 	.num_ports		= 6,
-	.pci_bar		= 4,
+	.switch_pci_bar		= 4,
+	.imdio_pci_bar		= 0,
 	.quirks			= OCELOT_PCS_PERFORMS_RATE_ADAPTATION,
+	.mdio_bus_alloc		= vsc9959_mdio_bus_alloc,
 };