[PATCH] phy: maxlinear: add Maxlinear GPY115/21x/24x driver

[Xu Liang <lxu@maxlinear.com>]

---
 drivers/net/phy/Kconfig   |   5 +
 drivers/net/phy/Makefile  |   1 +
 drivers/net/phy/mxl-gpy.c | 537 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 543 insertions(+)
 create mode 100644 drivers/net/phy/mxl-gpy.c

diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index 288bf405ebdb..7f1a0d62d83a 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -186,6 +186,11 @@ config INTEL_XWAY_PHY
 	  PEF 7061, PEF 7071 and PEF 7072 or integrated into the Intel
 	  SoCs xRX200, xRX300, xRX330, xRX350 and xRX550.
 
+config MXL_GPHY
+	tristate "Maxlinear 2.5G PHYs"
+	help
+	  Support for the Maxlinear 2.5G PHYs.
+
 config LSI_ET1011C_PHY
 	tristate "LSI ET1011C PHY"
 	help
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index bcda7ed2455d..28aa2a198d00 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_DP83TC811_PHY)	+= dp83tc811.o
 obj-$(CONFIG_FIXED_PHY)		+= fixed_phy.o
 obj-$(CONFIG_ICPLUS_PHY)	+= icplus.o
 obj-$(CONFIG_INTEL_XWAY_PHY)	+= intel-xway.o
+obj-$(CONFIG_MXL_GPHY)          += mxl-gpy.o
 obj-$(CONFIG_LSI_ET1011C_PHY)	+= et1011c.o
 obj-$(CONFIG_LXT_PHY)		+= lxt.o
 obj-$(CONFIG_MARVELL_10G_PHY)	+= marvell10g.o
diff --git a/drivers/net/phy/mxl-gpy.c b/drivers/net/phy/mxl-gpy.c
new file mode 100644
index 000000000000..757e65e48567
--- /dev/null
+++ b/drivers/net/phy/mxl-gpy.c
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2021 Maxlinear Corporation
+ * Copyright (C) 2020 Intel Corporation
+ *
+ * Maxlinear Ethernet GPY
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/bitfield.h>
+#include <linux/phy.h>
+#include <linux/netdevice.h>
+
+/* PHY ID */
+#define PHY_ID_GPY		0x67C9DC00
+#define PHY_ID_MASK		GENMASK(31, 10)
+
+#define PHY_MIISTAT		0x18	/* MII state */
+#define PHY_IMASK		0x19	/* interrupt mask */
+#define PHY_ISTAT		0x1A	/* interrupt status */
+#define PHY_FWV			0x1E	/* firmware version */
+
+#define PHY_MIISTAT_SPD_MASK	GENMASK(2, 0)
+#define PHY_MIISTAT_DPX		BIT(3)
+#define PHY_MIISTAT_LS		BIT(10)
+
+#define PHY_MIISTAT_SPD_10	0
+#define PHY_MIISTAT_SPD_100	1
+#define PHY_MIISTAT_SPD_1000	2
+#define PHY_MIISTAT_SPD_2500	4
+
+#define PHY_IMASK_WOL		BIT(15)	/* Wake-on-LAN */
+#define PHY_IMASK_ANC		BIT(10)	/* Auto-Neg complete */
+#define PHY_IMASK_ADSC		BIT(5)	/* Link auto-downspeed detect */
+#define PHY_IMASK_DXMC		BIT(2)	/* Duplex mode change */
+#define PHY_IMASK_LSPC		BIT(1)	/* Link speed change */
+#define PHY_IMASK_LSTC		BIT(0)	/* Link state change */
+#define PHY_IMASK_MASK		(PHY_IMASK_LSTC | \
+				 PHY_IMASK_LSPC | \
+				 PHY_IMASK_DXMC | \
+				 PHY_IMASK_ADSC | \
+				 PHY_IMASK_ANC)
+
+#define PHY_FWV_TYPE_MASK	GENMASK(11, 8)
+#define PHY_FWV_MINOR_MASK	GENMASK(7, 0)
+
+/* ANEG dev */
+#define ANEG_MGBT_AN_CTRL	0x20
+#define ANEG_MGBT_AN_STAT	0x21
+#define CTRL_AB_2G5BT_BIT	BIT(7)
+#define CTRL_AB_FR_2G5BT	BIT(5)
+#define STAT_AB_2G5BT_BIT	BIT(5)
+#define STAT_AB_FR_2G5BT	BIT(3)
+
+/* SGMII */
+#define VSPEC1_SGMII_CTRL	0x08
+#define VSPEC1_SGMII_CTRL_ANEN	BIT(12)		/* Aneg enable */
+#define VSPEC1_SGMII_CTRL_ANRS	BIT(9)		/* Restart Aneg */
+#define VSPEC1_SGMII_ANEN_ANRS	(VSPEC1_SGMII_CTRL_ANEN | \
+				 VSPEC1_SGMII_CTRL_ANRS)
+
+/* WoL */
+#define VPSPEC2_WOL_CTL		0x0E06
+#define VPSPEC2_WOL_AD01	0x0E08
+#define VPSPEC2_WOL_AD23	0x0E09
+#define VPSPEC2_WOL_AD45	0x0E0A
+#define WOL_EN			BIT(0)
+
+static int gpy_read_abilities(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = genphy_read_abilities(phydev);
+	if (ret < 0)
+		return ret;
+
+	/* Detect 2.5G/5G support. */
+	ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_STAT2);
+	if (ret < 0)
+		return ret;
+	if (!(ret & MDIO_PMA_STAT2_EXTABLE))
+		return 0;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_EXTABLE);
+	if (ret < 0)
+		return ret;
+	if (!(ret & MDIO_PMA_EXTABLE_NBT))
+		return 0;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_NG_EXTABLE);
+	if (ret < 0)
+		return ret;
+
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_2500baseT_Full_BIT,
+			 phydev->supported,
+			 ret & MDIO_PMA_NG_EXTABLE_2_5GBT);
+
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_5000baseT_Full_BIT,
+			 phydev->supported,
+			 ret & MDIO_PMA_NG_EXTABLE_5GBT);
+
+	return 0;
+}
+
+static int gpy_config_init(struct phy_device *phydev)
+{
+	int ret, fw_ver;
+
+	/* Show GPY PHY FW version in dmesg */
+	fw_ver = phy_read(phydev, PHY_FWV);
+	if (fw_ver < 0)
+		return fw_ver;
+
+	phydev_info(phydev, "Firmware Version: 0x%04X (%s)\n", fw_ver,
+		    (fw_ver & BIT(15)) ? "release" : "test");
+
+	/* Mask all interrupts */
+	ret = phy_write(phydev, PHY_IMASK, 0);
+	if (ret)
+		return ret;
+
+	/* Clear all pending interrupts */
+	return phy_read(phydev, PHY_ISTAT);
+}
+
+static bool gpy_sgmii_need_reaneg(struct phy_device *phydev)
+{
+	struct {
+		int type;
+		int minor;
+	} table[] = {
+		{7, 0x6D},
+		{8, 0x6D},
+		{9, 0x73},
+	};
+
+	int fw_ver, fw_type, fw_minor;
+	size_t i;
+
+	fw_ver = phy_read(phydev, PHY_FWV);
+	if (fw_ver < 0)
+		return true;
+
+	fw_type = FIELD_GET(PHY_FWV_TYPE_MASK, fw_ver);
+	fw_minor = FIELD_GET(PHY_FWV_MINOR_MASK, fw_ver);
+
+	for (i = 0; i < ARRAY_SIZE(table); i++) {
+		if (fw_type != table[i].type)
+			continue;
+		if (fw_minor < table[i].minor)
+			return true;
+		break;
+	}
+
+	return false;
+}
+
+static bool gpy_sgmii_2p5g_chk(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = phy_read(phydev, PHY_MIISTAT);
+	if (ret < 0) {
+		phydev_err(phydev, "Error: MDIO register access failed: %d\n",
+			   ret);
+		return false;
+	}
+
+	if (!(ret & PHY_MIISTAT_LS)
+	    || FIELD_GET(PHY_MIISTAT_SPD_MASK, ret) != PHY_MIISTAT_SPD_2500)
+		return false;
+
+	phydev->speed = SPEED_2500;
+	phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
+	phy_modify_mmd_changed(phydev, MDIO_MMD_VEND1,
+			       VSPEC1_SGMII_CTRL,
+			       VSPEC1_SGMII_CTRL_ANEN, 0);
+	return true;
+}
+
+static bool gpy_sgmii_aneg_en(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_VEND1, VSPEC1_SGMII_CTRL);
+	if (ret < 0) {
+		phydev_err(phydev, "Error: MMD register access failed: %d\n",
+			   ret);
+		return true;
+	}
+
+	return (ret & VSPEC1_SGMII_CTRL_ANEN) ? true : false;
+}
+
+static int gpy_config_aneg(struct phy_device *phydev)
+{
+	bool changed = false;
+	u32 adv;
+	int ret;
+
+	if (phydev->autoneg == AUTONEG_DISABLE) {
+		return phydev->duplex != DUPLEX_FULL
+			? genphy_setup_forced(phydev)
+			: genphy_c45_pma_setup_forced(phydev);
+	}
+
+	ret = genphy_c45_an_config_aneg(phydev);
+	if (ret < 0)
+		return ret;
+	if (ret)
+		changed = true;
+
+	adv = linkmode_adv_to_mii_ctrl1000_t(phydev->advertising);
+	ret = phy_modify_changed(phydev, MII_CTRL1000,
+				 ADVERTISE_1000FULL | ADVERTISE_1000HALF,
+				 adv);
+	if (ret < 0)
+		return ret;
+	if (ret > 0)
+		changed = true;
+
+	ret = genphy_c45_check_and_restart_aneg(phydev, changed);
+	if (ret < 0)
+		return ret;
+
+	if (phydev->interface == PHY_INTERFACE_MODE_USXGMII
+	    || phydev->interface == PHY_INTERFACE_MODE_INTERNAL)
+		return 0;
+
+	/* No need to trigger re-ANEG if SGMII link speed is 2.5G
+	 * or SGMII ANEG is disabled.
+	 */
+	if (!gpy_sgmii_need_reaneg(phydev) || gpy_sgmii_2p5g_chk(phydev)
+	    || !gpy_sgmii_aneg_en(phydev))
+		return 0;
+
+	/* There is a design constraint in GPY2xx device where SGMII AN is
+	 * only triggered when there is change of speed. If, PHY link
+	 * partner`s speed is still same even after PHY TPI is down and up
+	 * again, SGMII AN is not triggered and hence no new in-band message
+	 * from GPY to MAC side SGMII.
+	 * This could cause an issue during power up, when PHY is up prior to
+	 * MAC. At this condition, once MAC side SGMII is up, MAC side SGMII
+	 * wouldn`t receive new in-band message from GPY with correct link
+	 * status, speed and duplex info.
+	 *
+	 * 1) If PHY is already up and TPI link status is still down (such as
+	 *    hard reboot), TPI link status is polled for 4 seconds before
+	 *    retriggerring SGMII AN.
+	 * 2) If PHY is already up and TPI link status is also up (such as soft
+	 *    reboot), polling of TPI link status is not needed and SGMII AN is
+	 *    immediately retriggered.
+	 * 3) Other conditions such as PHY is down, speed change etc, skip
+	 *    retriggering SGMII AN. Note: in case of speed change, GPY FW will
+	 *    initiate SGMII AN.
+	 */
+
+	if (phydev->state != PHY_UP)
+		return 0;
+
+	ret = phy_read_poll_timeout(phydev, MII_BMSR, ret, ret & BMSR_LSTATUS,
+				    20000, 4000000, false);
+	if (ret == -ETIMEDOUT)
+		return 0;
+	else if (ret < 0)
+		return ret;
+
+	/* Trigger SGMII AN. */
+	return phy_modify_mmd_changed(phydev, MDIO_MMD_VEND1, VSPEC1_SGMII_CTRL,
+				      VSPEC1_SGMII_CTRL_ANRS,
+				      VSPEC1_SGMII_CTRL_ANRS);
+}
+
+static void gpy_update_interface(struct phy_device *phydev)
+{
+	int ret;
+
+	/* Interface mode is fixed for USXGMII and integrated PHY */
+	if (phydev->interface == PHY_INTERFACE_MODE_USXGMII
+	    || phydev->interface == PHY_INTERFACE_MODE_INTERNAL)
+		return;
+
+	/* Automatically switch SERDES interface between SGMII and 2500-BaseX
+	 * according to speed. Disable ANEG in 2500-BaseX mode.
+	 */
+	switch (phydev->speed) {
+	case SPEED_2500:
+		phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
+		ret = phy_modify_mmd_changed(phydev, MDIO_MMD_VEND1,
+					     VSPEC1_SGMII_CTRL,
+					     VSPEC1_SGMII_CTRL_ANEN, 0);
+		if (ret < 0)
+			phydev_err(phydev,
+				   "Error: Disable of SGMII ANEG failed: %d\n",
+				   ret);
+		break;
+	case SPEED_1000:
+	case SPEED_100:
+	case SPEED_10:
+		phydev->interface = PHY_INTERFACE_MODE_SGMII;
+		if (gpy_sgmii_aneg_en(phydev))
+			break;
+		/* Enable and restart SGMII ANEG for 10/100/1000Mbps link speed
+		 * if ANEG is disabled (in 2500-BaseX mode).
+		 */
+		ret = phy_modify_mmd_changed(phydev, MDIO_MMD_VEND1,
+					     VSPEC1_SGMII_CTRL,
+					     VSPEC1_SGMII_ANEN_ANRS,
+					     VSPEC1_SGMII_ANEN_ANRS);
+		if (ret < 0)
+			phydev_err(phydev,
+				   "Error: Enable of SGMII ANEG failed: %d\n",
+				   ret);
+		break;
+	}
+}
+
+static int gpy_read_status(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = genphy_update_link(phydev);
+	if (ret)
+		return ret;
+
+	phydev->speed = SPEED_UNKNOWN;
+	phydev->duplex = DUPLEX_UNKNOWN;
+	phydev->pause = 0;
+	phydev->asym_pause = 0;
+
+	if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
+		ret = genphy_c45_read_lpa(phydev);
+		if (ret < 0)
+			return ret;
+
+		/* Read the link partner's 1G advertisement */
+		ret = phy_read(phydev, MII_STAT1000);
+		if (ret < 0)
+			return ret;
+		mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising, ret);
+	} else if (phydev->autoneg == AUTONEG_DISABLE) {
+		linkmode_zero(phydev->lp_advertising);
+	}
+
+	ret = phy_read(phydev, PHY_MIISTAT);
+	if (ret < 0)
+		return ret;
+
+	phydev->link = (ret & PHY_MIISTAT_LS) ? 1 : 0;
+	phydev->duplex = (ret & PHY_MIISTAT_DPX) ? DUPLEX_FULL : DUPLEX_HALF;
+	switch (FIELD_GET(PHY_MIISTAT_SPD_MASK, ret)) {
+	case PHY_MIISTAT_SPD_10:
+		phydev->speed = SPEED_10;
+		break;
+	case PHY_MIISTAT_SPD_100:
+		phydev->speed = SPEED_100;
+		break;
+	case PHY_MIISTAT_SPD_1000:
+		phydev->speed = SPEED_1000;
+		break;
+	case PHY_MIISTAT_SPD_2500:
+		phydev->speed = SPEED_2500;
+		break;
+	}
+
+	if (phydev->link)
+		gpy_update_interface(phydev);
+
+	return 0;
+}
+
+static int gpy_config_intr(struct phy_device *phydev)
+{
+	u16 mask = 0;
+
+	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
+		mask = PHY_IMASK_MASK;
+
+	return phy_write(phydev, PHY_IMASK, mask);
+}
+
+static irqreturn_t gpy_handle_interrupt(struct phy_device *phydev)
+{
+	int reg;
+
+	reg = phy_read(phydev, PHY_ISTAT);
+	if (reg < 0) {
+		phy_error(phydev);
+		return IRQ_NONE;
+	}
+
+	if (!(reg & PHY_IMASK_MASK))
+		return IRQ_NONE;
+
+	phy_trigger_machine(phydev);
+
+	return IRQ_HANDLED;
+}
+
+static int gpy_set_wol(struct phy_device *phydev,
+		       struct ethtool_wolinfo *wol)
+{
+	struct net_device *attach_dev = phydev->attached_dev;
+	int ret;
+
+	if (wol->wolopts & WAKE_MAGIC) {
+		/* MAC address - Byte0:Byte1:Byte2:Byte3:Byte4:Byte5
+		 * VPSPEC2_WOL_AD45 = Byte0:Byte1
+		 * VPSPEC2_WOL_AD23 = Byte2:Byte3
+		 * VPSPEC2_WOL_AD01 = Byte4:Byte5
+		 */
+		ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2,
+				       VPSPEC2_WOL_AD45,
+				       ((attach_dev->dev_addr[0] << 8) |
+				       attach_dev->dev_addr[1]));
+		if (ret < 0)
+			return ret;
+
+		ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2,
+				       VPSPEC2_WOL_AD23,
+				       ((attach_dev->dev_addr[2] << 8) |
+				       attach_dev->dev_addr[3]));
+		if (ret < 0)
+			return ret;
+
+		ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2,
+				       VPSPEC2_WOL_AD01,
+				       ((attach_dev->dev_addr[4] << 8) |
+				       attach_dev->dev_addr[5]));
+		if (ret < 0)
+			return ret;
+
+		/* Enable the WOL interrupt */
+		ret = phy_write(phydev, PHY_IMASK, PHY_IMASK_WOL);
+		if (ret < 0)
+			return ret;
+
+		/* Enable magic packet matching */
+		ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2,
+				       VPSPEC2_WOL_CTL,
+				       WOL_EN);
+		if (ret < 0)
+			return ret;
+
+		/* Clear the interrupt status register */
+		ret = phy_read(phydev, PHY_ISTAT);
+		if (ret < 0)
+			return ret;
+
+	} else {
+		/* Disable magic packet matching */
+		ret = phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2,
+					 VPSPEC2_WOL_CTL,
+					 WOL_EN);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (wol->wolopts & WAKE_PHY) {
+		/* Enable the link state change interrupt */
+		ret = phy_set_bits(phydev, PHY_IMASK, PHY_IMASK_LSTC);
+		if (ret < 0)
+			return ret;
+
+		/* Clear the interrupt status register */
+		ret = phy_read(phydev, PHY_ISTAT);
+	} else {
+		/* Disable the link state change interrupt */
+		ret = phy_clear_bits(phydev, PHY_IMASK, PHY_IMASK_LSTC);
+	}
+
+	return ret;
+}
+
+static void gpy_get_wol(struct phy_device *phydev,
+			struct ethtool_wolinfo *wol)
+{
+	int ret;
+
+	wol->supported = WAKE_MAGIC | WAKE_PHY;
+	wol->wolopts = 0;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, VPSPEC2_WOL_CTL);
+	if (ret & WOL_EN)
+		wol->wolopts |= WAKE_MAGIC;
+
+	ret = phy_read(phydev, PHY_IMASK);
+	if (ret & PHY_IMASK_LSTC)
+		wol->wolopts |= WAKE_PHY;
+}
+
+static int gpy_loopback(struct phy_device *phydev, bool enable)
+{
+	int ret;
+
+	ret = genphy_loopback(phydev, enable);
+	if (!ret) {
+		/* It takes some time for PHY deviceto switch
+		 * into/out-of loopback mode.
+		 */
+		usleep_range(100, 200);
+	}
+
+	return ret;
+}
+
+static struct phy_driver gpy_drivers[] = {
+	{
+		.phy_id		= PHY_ID_GPY,
+		.phy_id_mask	= PHY_ID_MASK,
+		.name		= "Maxlinear Ethernet GPY",
+		.get_features	= gpy_read_abilities,
+		.config_init	= gpy_config_init,
+		.suspend	= genphy_suspend,
+		.resume		= genphy_resume,
+		.config_aneg	= gpy_config_aneg,
+		.aneg_done	= genphy_c45_aneg_done,
+		.read_status	= gpy_read_status,
+		.config_intr	= gpy_config_intr,
+		.handle_interrupt = gpy_handle_interrupt,
+		.set_wol	= gpy_set_wol,
+		.get_wol	= gpy_get_wol,
+		.set_loopback	= gpy_loopback,
+	},
+};
+module_phy_driver(gpy_drivers);
+
+static struct mdio_device_id __maybe_unused gpy_tbl[] = {
+	{PHY_ID_GPY, PHY_ID_MASK},
+	{ }
+};
+MODULE_DEVICE_TABLE(mdio, gpy_tbl);
+
+MODULE_DESCRIPTION("Maxlinear Ethernet GPY Driver");
+MODULE_AUTHOR("Maxlinear Corporation");
+MODULE_LICENSE("GPL");
-- 
2.17.1