root/drivers/net/ethernet/stmicro/stmmac/dwmac-eic7700.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Eswin DWC Ethernet linux driver
 *
 * Copyright 2025, Beijing ESWIN Computing Technology Co., Ltd.
 *
 * Authors:
 *   Zhi Li <lizhi2@eswincomputing.com>
 *   Shuang Liang <liangshuang@eswincomputing.com>
 *   Shangjuan Wei <weishangjuan@eswincomputing.com>
 */

#include <linux/platform_device.h>
#include <linux/mfd/syscon.h>
#include <linux/pm_runtime.h>
#include <linux/stmmac.h>
#include <linux/regmap.h>
#include <linux/of.h>

#include "stmmac_platform.h"

/* eth_phy_ctrl_offset eth0:0x100 */
#define EIC7700_ETH_TX_CLK_SEL          BIT(16)
#define EIC7700_ETH_PHY_INTF_SELI       BIT(0)

/* eth_axi_lp_ctrl_offset eth0:0x108 */
#define EIC7700_ETH_CSYSREQ_VAL         BIT(0)

/*
 * TX/RX Clock Delay Bit Masks:
 * - TX Delay: bits [14:8] — TX_CLK delay (unit: 0.1ns per bit)
 * - RX Delay: bits [30:24] — RX_CLK delay (unit: 0.1ns per bit)
 */
#define EIC7700_ETH_TX_ADJ_DELAY        GENMASK(14, 8)
#define EIC7700_ETH_RX_ADJ_DELAY        GENMASK(30, 24)

#define EIC7700_MAX_DELAY_UNIT 0x7F

static const char * const eic7700_clk_names[] = {
        "tx", "axi", "cfg",
};

struct eic7700_qos_priv {
        struct plat_stmmacenet_data *plat_dat;
};

static int eic7700_clks_config(void *priv, bool enabled)
{
        struct eic7700_qos_priv *dwc = (struct eic7700_qos_priv *)priv;
        struct plat_stmmacenet_data *plat = dwc->plat_dat;
        int ret = 0;

        if (enabled)
                ret = clk_bulk_prepare_enable(plat->num_clks, plat->clks);
        else
                clk_bulk_disable_unprepare(plat->num_clks, plat->clks);

        return ret;
}

static int eic7700_dwmac_init(struct device *dev, void *priv)
{
        struct eic7700_qos_priv *dwc = priv;

        return eic7700_clks_config(dwc, true);
}

static void eic7700_dwmac_exit(struct device *dev, void *priv)
{
        struct eic7700_qos_priv *dwc = priv;

        eic7700_clks_config(dwc, false);
}

static int eic7700_dwmac_suspend(struct device *dev, void *priv)
{
        return pm_runtime_force_suspend(dev);
}

static int eic7700_dwmac_resume(struct device *dev, void *priv)
{
        int ret;

        ret = pm_runtime_force_resume(dev);
        if (ret)
                dev_err(dev, "%s failed: %d\n", __func__, ret);

        return ret;
}

static int eic7700_dwmac_probe(struct platform_device *pdev)
{
        struct plat_stmmacenet_data *plat_dat;
        struct stmmac_resources stmmac_res;
        struct eic7700_qos_priv *dwc_priv;
        struct regmap *eic7700_hsp_regmap;
        u32 eth_axi_lp_ctrl_offset;
        u32 eth_phy_ctrl_offset;
        u32 eth_phy_ctrl_regset;
        u32 eth_rxd_dly_offset;
        u32 eth_dly_param = 0;
        u32 delay_ps;
        int i, ret;

        ret = stmmac_get_platform_resources(pdev, &stmmac_res);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                "failed to get resources\n");

        plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
        if (IS_ERR(plat_dat))
                return dev_err_probe(&pdev->dev, PTR_ERR(plat_dat),
                                "dt configuration failed\n");

        dwc_priv = devm_kzalloc(&pdev->dev, sizeof(*dwc_priv), GFP_KERNEL);
        if (!dwc_priv)
                return -ENOMEM;

        /* Read rx-internal-delay-ps and update rx_clk delay */
        if (!of_property_read_u32(pdev->dev.of_node,
                                  "rx-internal-delay-ps", &delay_ps)) {
                u32 val = min(delay_ps / 100, EIC7700_MAX_DELAY_UNIT);

                eth_dly_param &= ~EIC7700_ETH_RX_ADJ_DELAY;
                eth_dly_param |= FIELD_PREP(EIC7700_ETH_RX_ADJ_DELAY, val);
        } else {
                return dev_err_probe(&pdev->dev, -EINVAL,
                        "missing required property rx-internal-delay-ps\n");
        }

        /* Read tx-internal-delay-ps and update tx_clk delay */
        if (!of_property_read_u32(pdev->dev.of_node,
                                  "tx-internal-delay-ps", &delay_ps)) {
                u32 val = min(delay_ps / 100, EIC7700_MAX_DELAY_UNIT);

                eth_dly_param &= ~EIC7700_ETH_TX_ADJ_DELAY;
                eth_dly_param |= FIELD_PREP(EIC7700_ETH_TX_ADJ_DELAY, val);
        } else {
                return dev_err_probe(&pdev->dev, -EINVAL,
                        "missing required property tx-internal-delay-ps\n");
        }

        eic7700_hsp_regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
                                                             "eswin,hsp-sp-csr");
        if (IS_ERR(eic7700_hsp_regmap))
                return dev_err_probe(&pdev->dev,
                                PTR_ERR(eic7700_hsp_regmap),
                                "Failed to get hsp-sp-csr regmap\n");

        ret = of_property_read_u32_index(pdev->dev.of_node,
                                         "eswin,hsp-sp-csr",
                                         1, &eth_phy_ctrl_offset);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                     "can't get eth_phy_ctrl_offset\n");

        regmap_read(eic7700_hsp_regmap, eth_phy_ctrl_offset,
                    &eth_phy_ctrl_regset);
        eth_phy_ctrl_regset |=
                (EIC7700_ETH_TX_CLK_SEL | EIC7700_ETH_PHY_INTF_SELI);
        regmap_write(eic7700_hsp_regmap, eth_phy_ctrl_offset,
                     eth_phy_ctrl_regset);

        ret = of_property_read_u32_index(pdev->dev.of_node,
                                         "eswin,hsp-sp-csr",
                                         2, &eth_axi_lp_ctrl_offset);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                     "can't get eth_axi_lp_ctrl_offset\n");

        regmap_write(eic7700_hsp_regmap, eth_axi_lp_ctrl_offset,
                     EIC7700_ETH_CSYSREQ_VAL);

        ret = of_property_read_u32_index(pdev->dev.of_node,
                                         "eswin,hsp-sp-csr",
                                         3, &eth_rxd_dly_offset);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                     "can't get eth_rxd_dly_offset\n");

        regmap_write(eic7700_hsp_regmap, eth_rxd_dly_offset,
                     eth_dly_param);

        plat_dat->num_clks = ARRAY_SIZE(eic7700_clk_names);
        plat_dat->clks = devm_kcalloc(&pdev->dev,
                                      plat_dat->num_clks,
                                      sizeof(*plat_dat->clks),
                                      GFP_KERNEL);
        if (!plat_dat->clks)
                return -ENOMEM;

        for (i = 0; i < ARRAY_SIZE(eic7700_clk_names); i++)
                plat_dat->clks[i].id = eic7700_clk_names[i];

        ret = devm_clk_bulk_get_optional(&pdev->dev,
                                         plat_dat->num_clks,
                                         plat_dat->clks);
        if (ret)
                return dev_err_probe(&pdev->dev, ret,
                                     "Failed to get clocks\n");

        plat_dat->clk_tx_i = stmmac_pltfr_find_clk(plat_dat, "tx");
        plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
        plat_dat->clks_config = eic7700_clks_config;
        plat_dat->bsp_priv = dwc_priv;
        dwc_priv->plat_dat = plat_dat;
        plat_dat->init = eic7700_dwmac_init;
        plat_dat->exit = eic7700_dwmac_exit;
        plat_dat->suspend = eic7700_dwmac_suspend;
        plat_dat->resume = eic7700_dwmac_resume;

        return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
}

static const struct of_device_id eic7700_dwmac_match[] = {
        { .compatible = "eswin,eic7700-qos-eth" },
        { }
};
MODULE_DEVICE_TABLE(of, eic7700_dwmac_match);

static struct platform_driver eic7700_dwmac_driver = {
        .probe  = eic7700_dwmac_probe,
        .driver = {
                .name           = "eic7700-eth-dwmac",
                .pm             = &stmmac_pltfr_pm_ops,
                .of_match_table = eic7700_dwmac_match,
        },
};
module_platform_driver(eic7700_dwmac_driver);

MODULE_AUTHOR("Zhi Li <lizhi2@eswincomputing.com>");
MODULE_AUTHOR("Shuang Liang <liangshuang@eswincomputing.com>");
MODULE_AUTHOR("Shangjuan Wei <weishangjuan@eswincomputing.com>");
MODULE_DESCRIPTION("Eswin eic7700 qos ethernet driver");
MODULE_LICENSE("GPL");