--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MediaTek 10GE SerDes XFI T-PHY driver
+ *
+ * Copyright (c) 2024 Daniel Golle <daniel@makrotopia.org>
+ *                    Bc-bocun Chen <bc-bocun.chen@mediatek.com>
+ * based on mtk_usxgmii.c and mtk_sgmii.c found in MediaTek's SDK (GPL-2.0)
+ * Copyright (c) 2022 MediaTek Inc.
+ * Author: Henry Yen <henry.yen@mediatek.com>
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/phy.h>
+#include <linux/phy/phy.h>
+
+#include "phy-mtk-io.h"
+
+#define MTK_XFI_TPHY_NUM_CLOCKS                2
+
+#define REG_DIG_GLB_70                 0x0070
+#define  XTP_PCS_RX_EQ_IN_PROGRESS(x)  FIELD_PREP(GENMASK(25, 24), (x))
+#define  XTP_PCS_MODE_MASK             GENMASK(17, 16)
+#define  XTP_PCS_MODE(x)               FIELD_PREP(GENMASK(17, 16), (x))
+#define  XTP_PCS_RST_B                 BIT(15)
+#define  XTP_FRC_PCS_RST_B             BIT(14)
+#define  XTP_PCS_PWD_SYNC_MASK         GENMASK(13, 12)
+#define  XTP_PCS_PWD_SYNC(x)           FIELD_PREP(XTP_PCS_PWD_SYNC_MASK, (x))
+#define  XTP_PCS_PWD_ASYNC_MASK                GENMASK(11, 10)
+#define  XTP_PCS_PWD_ASYNC(x)          FIELD_PREP(XTP_PCS_PWD_ASYNC_MASK, (x))
+#define  XTP_FRC_PCS_PWD_ASYNC         BIT(8)
+#define  XTP_PCS_UPDT                  BIT(4)
+#define  XTP_PCS_IN_FR_RG              BIT(0)
+
+#define REG_DIG_GLB_F4                 0x00f4
+#define  XFI_DPHY_PCS_SEL              BIT(0)
+#define   XFI_DPHY_PCS_SEL_SGMII       FIELD_PREP(XFI_DPHY_PCS_SEL, 1)
+#define   XFI_DPHY_PCS_SEL_USXGMII     FIELD_PREP(XFI_DPHY_PCS_SEL, 0)
+#define  XFI_DPHY_AD_SGDT_FRC_EN       BIT(5)
+
+#define REG_DIG_LN_TRX_40              0x3040
+#define  XTP_LN_FRC_TX_DATA_EN         BIT(29)
+#define  XTP_LN_TX_DATA_EN             BIT(28)
+
+#define REG_DIG_LN_TRX_B0              0x30b0
+#define  XTP_LN_FRC_TX_MACCK_EN                BIT(5)
+#define  XTP_LN_TX_MACCK_EN            BIT(4)
+
+#define REG_ANA_GLB_D0                 0x90d0
+#define  XTP_GLB_USXGMII_SEL_MASK      GENMASK(3, 1)
+#define  XTP_GLB_USXGMII_SEL(x)                FIELD_PREP(GENMASK(3, 1), (x))
+#define  XTP_GLB_USXGMII_EN            BIT(0)
+
+/**
+ * struct mtk_xfi_tphy - run-time data of the XFI phy instance
+ * @base: IO memory area to access phy registers.
+ * @dev: Kernel device used to output prefixed debug info.
+ * @reset: Reset control corresponding to the phy instance.
+ * @clocks: All clocks required for the phy to operate.
+ * @da_war: Enables work-around for 10GBase-R mode.
+ */
+struct mtk_xfi_tphy {
+       void __iomem            *base;
+       struct device           *dev;
+       struct reset_control    *reset;
+       struct clk_bulk_data    clocks[MTK_XFI_TPHY_NUM_CLOCKS];
+       bool                    da_war;
+};
+
+/**
+ * mtk_xfi_tphy_setup() - Setup phy for specified interface mode.
+ * @xfi_tphy: XFI phy instance.
+ * @interface: Ethernet interface mode
+ *
+ * The setup function is the condensed result of combining the 5 functions which
+ * setup the phy in MediaTek's GPL licensed public SDK sources. They can be found
+ * in mtk_sgmii.c[1] as well as mtk_usxgmii.c[2].
+ *
+ * Many magic values have been replaced by register and bit definitions, however,
+ * that has not been possible in all cases. While the vendor driver uses a
+ * sequence of 32-bit writes, here we try to only modify the actually required
+ * bits.
+ *
+ * [1]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/b72d6cba92bf9e29fb035c03052fa1e86664a25b/21.02/files/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_sgmii.c
+ *
+ * [2]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/dec96a1d9b82cdcda4a56453fd0b453d4cab4b85/21.02/files/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+ */
+static void mtk_xfi_tphy_setup(struct mtk_xfi_tphy *xfi_tphy,
+                              phy_interface_t interface)
+{
+       bool is_1g, is_2p5g, is_5g, is_10g, da_war, use_lynxi_pcs;
+
+       /* shorthands for specific clock speeds depending on interface mode */
+       is_1g = interface == PHY_INTERFACE_MODE_1000BASEX ||
+               interface == PHY_INTERFACE_MODE_SGMII;
+       is_2p5g = interface == PHY_INTERFACE_MODE_2500BASEX;
+       is_5g = interface == PHY_INTERFACE_MODE_5GBASER;
+       is_10g = interface == PHY_INTERFACE_MODE_10GBASER ||
+                interface == PHY_INTERFACE_MODE_USXGMII;
+
+       /* Is overriding 10GBase-R tuning value required? */
+       da_war = xfi_tphy->da_war && (interface == PHY_INTERFACE_MODE_10GBASER);
+
+       /* configure input mux to either
+        *  - USXGMII PCS (64b/66b coding) for 5G/10G
+        *  - LynxI PCS (8b/10b coding) for 1G/2.5G
+        */
+       use_lynxi_pcs = is_1g || is_2p5g;
+
+       dev_dbg(xfi_tphy->dev, "setting up for mode %s\n", phy_modes(interface));
+
+       /* Setup PLL setting */
+       mtk_phy_update_bits(xfi_tphy->base + 0x9024, 0x100000, is_10g ? 0x0 : 0x100000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x2020, 0x202000, is_5g ? 0x202000 : 0x0);
+       mtk_phy_update_bits(xfi_tphy->base + 0x2030, 0x500, is_1g ? 0x0 : 0x500);
+       mtk_phy_update_bits(xfi_tphy->base + 0x2034, 0xa00, is_1g ? 0x0 : 0xa00);
+       mtk_phy_update_bits(xfi_tphy->base + 0x2040, 0x340000, is_1g ? 0x200000 : 0x140000);
+
+       /* Setup RXFE BW setting */
+       mtk_phy_update_bits(xfi_tphy->base + 0x50f0, 0xc10, is_1g ? 0x410 : is_5g ? 0x800 : 0x400);
+       mtk_phy_update_bits(xfi_tphy->base + 0x50e0, 0x4000, is_5g ? 0x0 : 0x4000);
+
+       /* Setup RX CDR setting */
+       mtk_phy_update_bits(xfi_tphy->base + 0x506c, 0x30000, is_5g ? 0x0 : 0x30000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5070, 0x670000, is_5g ? 0x620000 : 0x50000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5074, 0x180000, is_5g ? 0x180000 : 0x0);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5078, 0xf000400, is_5g ? 0x8000000 :
+                                                                       0x7000400);
+       mtk_phy_update_bits(xfi_tphy->base + 0x507c, 0x5000500, is_5g ? 0x4000400 :
+                                                                       0x1000100);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5080, 0x1410, is_1g ? 0x400 : is_5g ? 0x1010 : 0x0);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5084, 0x30300, is_1g ? 0x30300 :
+                                                             is_5g ? 0x30100 :
+                                                                     0x100);
+       mtk_phy_update_bits(xfi_tphy->base + 0x5088, 0x60200, is_1g ? 0x20200 :
+                                                             is_5g ? 0x40000 :
+                                                                     0x20000);
+
+       /* Setting RXFE adaptation range setting */
+       mtk_phy_update_bits(xfi_tphy->base + 0x50e4, 0xc0000, is_5g ? 0x0 : 0xc0000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x50e8, 0x40000, is_5g ? 0x0 : 0x40000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x50ec, 0xa00, is_1g ? 0x200 : 0x800);
+       mtk_phy_update_bits(xfi_tphy->base + 0x50a8, 0xee0000, is_5g ? 0x800000 :
+                                                                      0x6e0000);
+       mtk_phy_update_bits(xfi_tphy->base + 0x6004, 0x190000, is_5g ? 0x0 : 0x190000);
+
+       if (is_10g)
+               writel(0x01423342, xfi_tphy->base + 0x00f8);
+       else if (is_5g)
+               writel(0x00a132a1, xfi_tphy->base + 0x00f8);
+       else if (is_2p5g)
+               writel(0x009c329c, xfi_tphy->base + 0x00f8);
+       else
+               writel(0x00fa32fa, xfi_tphy->base + 0x00f8);
+
+       /* Force SGDT_OUT off and select PCS */
+       mtk_phy_update_bits(xfi_tphy->base + REG_DIG_GLB_F4,
+                           XFI_DPHY_AD_SGDT_FRC_EN | XFI_DPHY_PCS_SEL,
+                           XFI_DPHY_AD_SGDT_FRC_EN |
+                           (use_lynxi_pcs ? XFI_DPHY_PCS_SEL_SGMII :
+                                            XFI_DPHY_PCS_SEL_USXGMII));
+
+       /* Force GLB_CKDET_OUT */
+       mtk_phy_set_bits(xfi_tphy->base + 0x0030, 0xc00);
+
+       /* Force AEQ on */
+       writel(XTP_PCS_RX_EQ_IN_PROGRESS(2) | XTP_PCS_PWD_SYNC(2) | XTP_PCS_PWD_ASYNC(2),
+              xfi_tphy->base + REG_DIG_GLB_70);
+
+       usleep_range(1, 5);
+       writel(XTP_LN_FRC_TX_DATA_EN, xfi_tphy->base + REG_DIG_LN_TRX_40);
+
+       /* Setup TX DA default value */
+       mtk_phy_update_bits(xfi_tphy->base + 0x30b0, 0x30, 0x20);
+       writel(0x00008a01, xfi_tphy->base + 0x3028);
+       writel(0x0000a884, xfi_tphy->base + 0x302c);
+       writel(0x00083002, xfi_tphy->base + 0x3024);
+
+       /* Setup RG default value */
+       if (use_lynxi_pcs) {
+               writel(0x00011110, xfi_tphy->base + 0x3010);
+               writel(0x40704000, xfi_tphy->base + 0x3048);
+       } else {
+               writel(0x00022220, xfi_tphy->base + 0x3010);
+               writel(0x0f020a01, xfi_tphy->base + 0x5064);
+               writel(0x06100600, xfi_tphy->base + 0x50b4);
+               if (interface == PHY_INTERFACE_MODE_USXGMII)
+                       writel(0x40704000, xfi_tphy->base + 0x3048);
+               else
+                       writel(0x47684100, xfi_tphy->base + 0x3048);
+       }
+
+       if (is_1g)
+               writel(0x0000c000, xfi_tphy->base + 0x3064);
+
+       /* Setup RX EQ initial value */
+       mtk_phy_update_bits(xfi_tphy->base + 0x3050, 0xa8000000,
+                           (interface != PHY_INTERFACE_MODE_10GBASER) ? 0xa8000000 : 0x0);
+       mtk_phy_update_bits(xfi_tphy->base + 0x3054, 0xaa,
+                           (interface != PHY_INTERFACE_MODE_10GBASER) ? 0xaa : 0x0);
+
+       if (!use_lynxi_pcs)
+               writel(0x00000f00, xfi_tphy->base + 0x306c);
+       else if (is_2p5g)
+               writel(0x22000f00, xfi_tphy->base + 0x306c);
+       else
+               writel(0x20200f00, xfi_tphy->base + 0x306c);
+
+       mtk_phy_update_bits(xfi_tphy->base + 0xa008, 0x10000, da_war ? 0x10000 : 0x0);
+
+       mtk_phy_update_bits(xfi_tphy->base + 0xa060, 0x50000, use_lynxi_pcs ? 0x50000 : 0x40000);
+
+       /* Setup PHYA speed */
+       mtk_phy_update_bits(xfi_tphy->base + REG_ANA_GLB_D0,
+                           XTP_GLB_USXGMII_SEL_MASK | XTP_GLB_USXGMII_EN,
+                           is_10g ?  XTP_GLB_USXGMII_SEL(0) :
+                           is_5g ?   XTP_GLB_USXGMII_SEL(1) :
+                           is_2p5g ? XTP_GLB_USXGMII_SEL(2) :
+                                     XTP_GLB_USXGMII_SEL(3));
+       mtk_phy_set_bits(xfi_tphy->base + REG_ANA_GLB_D0, XTP_GLB_USXGMII_EN);
+
+       /* Release reset */
+       mtk_phy_set_bits(xfi_tphy->base + REG_DIG_GLB_70,
+                        XTP_PCS_RST_B | XTP_FRC_PCS_RST_B);
+       usleep_range(150, 500);
+
+       /* Switch to P0 */
+       mtk_phy_update_bits(xfi_tphy->base + REG_DIG_GLB_70,
+                           XTP_PCS_IN_FR_RG |
+                           XTP_FRC_PCS_PWD_ASYNC |
+                           XTP_PCS_PWD_ASYNC_MASK |
+                           XTP_PCS_PWD_SYNC_MASK |
+                           XTP_PCS_UPDT,
+                           XTP_PCS_IN_FR_RG |
+                           XTP_FRC_PCS_PWD_ASYNC |
+                           XTP_PCS_UPDT);
+       usleep_range(1, 5);
+
+       mtk_phy_clear_bits(xfi_tphy->base + REG_DIG_GLB_70, XTP_PCS_UPDT);
+       usleep_range(15, 50);
+
+       if (use_lynxi_pcs) {
+               /* Switch to Gen2 */
+               mtk_phy_update_bits(xfi_tphy->base + REG_DIG_GLB_70,
+                                   XTP_PCS_MODE_MASK | XTP_PCS_UPDT,
+                                   XTP_PCS_MODE(1) | XTP_PCS_UPDT);
+       } else {
+               /* Switch to Gen3 */
+               mtk_phy_update_bits(xfi_tphy->base + REG_DIG_GLB_70,
+                                   XTP_PCS_MODE_MASK | XTP_PCS_UPDT,
+                                   XTP_PCS_MODE(2) | XTP_PCS_UPDT);
+       }
+       usleep_range(1, 5);
+
+       mtk_phy_clear_bits(xfi_tphy->base + REG_DIG_GLB_70, XTP_PCS_UPDT);
+
+       usleep_range(100, 500);
+
+       /* Enable MAC CK */
+       mtk_phy_set_bits(xfi_tphy->base + REG_DIG_LN_TRX_B0, XTP_LN_TX_MACCK_EN);
+       mtk_phy_clear_bits(xfi_tphy->base + REG_DIG_GLB_F4, XFI_DPHY_AD_SGDT_FRC_EN);
+
+       /* Enable TX data */
+       mtk_phy_set_bits(xfi_tphy->base + REG_DIG_LN_TRX_40,
+                        XTP_LN_FRC_TX_DATA_EN | XTP_LN_TX_DATA_EN);
+       usleep_range(400, 1000);
+}
+
+/**
+ * mtk_xfi_tphy_set_mode() - Setup phy for specified interface mode.
+ *
+ * @phy: Phy instance.
+ * @mode: Only PHY_MODE_ETHERNET is supported.
+ * @submode: An Ethernet interface mode.
+ *
+ * Validate selected mode and call function mtk_xfi_tphy_setup().
+ *
+ * Return:
+ * * %0 - OK
+ * * %-EINVAL - invalid mode
+ */
+static int mtk_xfi_tphy_set_mode(struct phy *phy, enum phy_mode mode, int
+                                submode)
+{
+       struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
+
+       if (mode != PHY_MODE_ETHERNET)
+               return -EINVAL;
+
+       switch (submode) {
+       case PHY_INTERFACE_MODE_1000BASEX:
+       case PHY_INTERFACE_MODE_2500BASEX:
+       case PHY_INTERFACE_MODE_SGMII:
+       case PHY_INTERFACE_MODE_5GBASER:
+       case PHY_INTERFACE_MODE_10GBASER:
+       case PHY_INTERFACE_MODE_USXGMII:
+               mtk_xfi_tphy_setup(xfi_tphy, submode);
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+/**
+ * mtk_xfi_tphy_reset() - Reset the phy.
+ *
+ * @phy: Phy instance.
+ *
+ * Reset the phy using the external reset controller.
+ *
+ * Return:
+ * %0 - OK
+ */
+static int mtk_xfi_tphy_reset(struct phy *phy)
+{
+       struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
+
+       reset_control_assert(xfi_tphy->reset);
+       usleep_range(100, 500);
+       reset_control_deassert(xfi_tphy->reset);
+       usleep_range(1, 10);
+
+       return 0;
+}
+
+/**
+ * mtk_xfi_tphy_power_on() - Power-on the phy.
+ *
+ * @phy: Phy instance.
+ *
+ * Prepare and enable all clocks required for the phy to operate.
+ *
+ * Return:
+ * See clk_bulk_prepare_enable().
+ */
+static int mtk_xfi_tphy_power_on(struct phy *phy)
+{
+       struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
+
+       return clk_bulk_prepare_enable(MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
+}
+
+/**
+ * mtk_xfi_tphy_power_off() - Power-off the phy.
+ *
+ * @phy: Phy instance.
+ *
+ * Disable and unprepare all clocks previously enabled.
+ *
+ * Return:
+ * See clk_bulk_prepare_disable().
+ */
+static int mtk_xfi_tphy_power_off(struct phy *phy)
+{
+       struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
+
+       clk_bulk_disable_unprepare(MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
+
+       return 0;
+}
+
+static const struct phy_ops mtk_xfi_tphy_ops = {
+       .power_on       = mtk_xfi_tphy_power_on,
+       .power_off      = mtk_xfi_tphy_power_off,
+       .set_mode       = mtk_xfi_tphy_set_mode,
+       .reset          = mtk_xfi_tphy_reset,
+       .owner          = THIS_MODULE,
+};
+
+/**
+ * mtk_xfi_tphy_probe() - Probe phy instance from Device Tree.
+ * @pdev: Matching platform device.
+ *
+ * The probe function gets IO resource, clocks, reset controller and
+ * whether the DA work-around for 10GBase-R is required from Device Tree and
+ * allocates memory for holding that information in a struct mtk_xfi_tphy.
+ *
+ * Return:
+ * * %0       - OK
+ * * %-ENODEV - Missing associated Device Tree node (should never happen).
+ * * %-ENOMEM - Out of memory.
+ * * Any error value which devm_platform_ioremap_resource(),
+ *   devm_clk_bulk_get(), devm_reset_control_get_exclusive(),
+ *   devm_phy_create() or devm_of_phy_provider_register() may return.
+ */
+static int mtk_xfi_tphy_probe(struct platform_device *pdev)
+{
+       struct device_node *np = pdev->dev.of_node;
+       struct phy_provider *phy_provider;
+       struct mtk_xfi_tphy *xfi_tphy;
+       struct phy *phy;
+       int ret;
+
+       if (!np)
+               return -ENODEV;
+
+       xfi_tphy = devm_kzalloc(&pdev->dev, sizeof(*xfi_tphy), GFP_KERNEL);
+       if (!xfi_tphy)
+               return -ENOMEM;
+
+       xfi_tphy->base = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(xfi_tphy->base))
+               return PTR_ERR(xfi_tphy->base);
+
+       xfi_tphy->dev = &pdev->dev;
+       xfi_tphy->clocks[0].id = "topxtal";
+       xfi_tphy->clocks[1].id = "xfipll";
+       ret = devm_clk_bulk_get(&pdev->dev, MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
+       if (ret)
+               return ret;
+
+       xfi_tphy->reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+       if (IS_ERR(xfi_tphy->reset))
+               return PTR_ERR(xfi_tphy->reset);
+
+       xfi_tphy->da_war = of_property_read_bool(np, "mediatek,usxgmii-performance-errata");
+
+       phy = devm_phy_create(&pdev->dev, NULL, &mtk_xfi_tphy_ops);
+       if (IS_ERR(phy))
+               return PTR_ERR(phy);
+
+       phy_set_drvdata(phy, xfi_tphy);
+       phy_provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
+
+       return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id mtk_xfi_tphy_match[] = {
+       { .compatible = "mediatek,mt7988-xfi-tphy", },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mtk_xfi_tphy_match);
+
+static struct platform_driver mtk_xfi_tphy_driver = {
+       .probe = mtk_xfi_tphy_probe,
+       .driver = {
+               .name = "mtk-xfi-tphy",
+               .of_match_table = mtk_xfi_tphy_match,
+       },
+};
+module_platform_driver(mtk_xfi_tphy_driver);
+
+MODULE_DESCRIPTION("MediaTek 10GE SerDes XFI T-PHY driver");
+MODULE_AUTHOR("Daniel Golle <daniel@makrotopia.org>");
+MODULE_AUTHOR("Bc-bocun Chen <bc-bocun.chen@mediatek.com>");
+MODULE_LICENSE("GPL");