|  | // SPDX-License-Identifier: GPL-2.0 | 
|  | /* | 
|  | * Copyright (c) 2014-2017, The Linux Foundation. All rights reserved. | 
|  | * Copyright (c) 2019, Linaro Ltd. | 
|  | */ | 
|  |  | 
|  | #include <linux/clk-provider.h> | 
|  | #include <linux/clk.h> | 
|  | #include <linux/iopoll.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/phy/phy.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/reset.h> | 
|  | #include <linux/slab.h> | 
|  |  | 
|  | #include <dt-bindings/phy/phy.h> | 
|  |  | 
|  | #define PCIE20_PARF_PHY_STTS         0x3c | 
|  | #define PCIE2_PHY_RESET_CTRL         0x44 | 
|  | #define PCIE20_PARF_PHY_REFCLK_CTRL2 0xa0 | 
|  | #define PCIE20_PARF_PHY_REFCLK_CTRL3 0xa4 | 
|  | #define PCIE20_PARF_PCS_SWING_CTRL1  0x88 | 
|  | #define PCIE20_PARF_PCS_SWING_CTRL2  0x8c | 
|  | #define PCIE20_PARF_PCS_DEEMPH1      0x74 | 
|  | #define PCIE20_PARF_PCS_DEEMPH2      0x78 | 
|  | #define PCIE20_PARF_PCS_DEEMPH3      0x7c | 
|  | #define PCIE20_PARF_CONFIGBITS       0x84 | 
|  | #define PCIE20_PARF_PHY_CTRL3        0x94 | 
|  | #define PCIE20_PARF_PCS_CTRL         0x80 | 
|  |  | 
|  | #define TX_AMP_VAL                   120 | 
|  | #define PHY_RX0_EQ_GEN1_VAL          0 | 
|  | #define PHY_RX0_EQ_GEN2_VAL          4 | 
|  | #define TX_DEEMPH_GEN1_VAL           24 | 
|  | #define TX_DEEMPH_GEN2_3_5DB_VAL     26 | 
|  | #define TX_DEEMPH_GEN2_6DB_VAL       36 | 
|  | #define PHY_TX0_TERM_OFFST_VAL       0 | 
|  |  | 
|  | struct qcom_phy { | 
|  | struct device *dev; | 
|  | void __iomem *base; | 
|  |  | 
|  | struct regulator_bulk_data vregs[2]; | 
|  |  | 
|  | struct reset_control *phy_reset; | 
|  | struct reset_control *pipe_reset; | 
|  | struct clk *pipe_clk; | 
|  | }; | 
|  |  | 
|  | static int qcom_pcie2_phy_init(struct phy *phy) | 
|  | { | 
|  | struct qcom_phy *qphy = phy_get_drvdata(phy); | 
|  | int ret; | 
|  |  | 
|  | ret = reset_control_deassert(qphy->phy_reset); | 
|  | if (ret) { | 
|  | dev_err(qphy->dev, "cannot deassert pipe reset\n"); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | ret = regulator_bulk_enable(ARRAY_SIZE(qphy->vregs), qphy->vregs); | 
|  | if (ret) | 
|  | reset_control_assert(qphy->phy_reset); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int qcom_pcie2_phy_power_on(struct phy *phy) | 
|  | { | 
|  | struct qcom_phy *qphy = phy_get_drvdata(phy); | 
|  | int ret; | 
|  | u32 val; | 
|  |  | 
|  | /* Program REF_CLK source */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2); | 
|  | val &= ~BIT(1); | 
|  | writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2); | 
|  |  | 
|  | usleep_range(1000, 2000); | 
|  |  | 
|  | /* Don't use PAD for refclock */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2); | 
|  | val &= ~BIT(0); | 
|  | writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2); | 
|  |  | 
|  | /* Program SSP ENABLE */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL3); | 
|  | val |= BIT(0); | 
|  | writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL3); | 
|  |  | 
|  | usleep_range(1000, 2000); | 
|  |  | 
|  | /* Assert Phy SW Reset */ | 
|  | val = readl(qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  | val |= BIT(0); | 
|  | writel(val, qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  |  | 
|  | /* Program Tx Amplitude */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_SWING_CTRL1); | 
|  | val &= ~0x7f; | 
|  | val |= TX_AMP_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_SWING_CTRL1); | 
|  |  | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_SWING_CTRL2); | 
|  | val &= ~0x7f; | 
|  | val |= TX_AMP_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_SWING_CTRL2); | 
|  |  | 
|  | /* Program De-Emphasis */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH1); | 
|  | val &= ~0x3f; | 
|  | val |= TX_DEEMPH_GEN2_6DB_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH1); | 
|  |  | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH2); | 
|  | val &= ~0x3f; | 
|  | val |= TX_DEEMPH_GEN2_3_5DB_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH2); | 
|  |  | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH3); | 
|  | val &= ~0x3f; | 
|  | val |= TX_DEEMPH_GEN1_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH3); | 
|  |  | 
|  | /* Program Rx_Eq */ | 
|  | val = readl(qphy->base + PCIE20_PARF_CONFIGBITS); | 
|  | val &= ~0x7; | 
|  | val |= PHY_RX0_EQ_GEN2_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_CONFIGBITS); | 
|  |  | 
|  | /* Program Tx0_term_offset */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PHY_CTRL3); | 
|  | val &= ~0x1f; | 
|  | val |= PHY_TX0_TERM_OFFST_VAL; | 
|  | writel(val, qphy->base + PCIE20_PARF_PHY_CTRL3); | 
|  |  | 
|  | /* disable Tx2Rx Loopback */ | 
|  | val = readl(qphy->base + PCIE20_PARF_PCS_CTRL); | 
|  | val &= ~BIT(1); | 
|  | writel(val, qphy->base + PCIE20_PARF_PCS_CTRL); | 
|  |  | 
|  | /* De-assert Phy SW Reset */ | 
|  | val = readl(qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  | val &= ~BIT(0); | 
|  | writel(val, qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  |  | 
|  | usleep_range(1000, 2000); | 
|  |  | 
|  | ret = reset_control_deassert(qphy->pipe_reset); | 
|  | if (ret) { | 
|  | dev_err(qphy->dev, "cannot deassert pipe reset\n"); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | clk_set_rate(qphy->pipe_clk, 250000000); | 
|  |  | 
|  | ret = clk_prepare_enable(qphy->pipe_clk); | 
|  | if (ret) { | 
|  | dev_err(qphy->dev, "failed to enable pipe clock\n"); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = readl_poll_timeout(qphy->base + PCIE20_PARF_PHY_STTS, val, | 
|  | !(val & BIT(0)), 1000, 10); | 
|  | if (ret) | 
|  | dev_err(qphy->dev, "phy initialization failed\n"); | 
|  |  | 
|  | out: | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int qcom_pcie2_phy_power_off(struct phy *phy) | 
|  | { | 
|  | struct qcom_phy *qphy = phy_get_drvdata(phy); | 
|  | u32 val; | 
|  |  | 
|  | val = readl(qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  | val |= BIT(0); | 
|  | writel(val, qphy->base + PCIE2_PHY_RESET_CTRL); | 
|  |  | 
|  | clk_disable_unprepare(qphy->pipe_clk); | 
|  | reset_control_assert(qphy->pipe_reset); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int qcom_pcie2_phy_exit(struct phy *phy) | 
|  | { | 
|  | struct qcom_phy *qphy = phy_get_drvdata(phy); | 
|  |  | 
|  | regulator_bulk_disable(ARRAY_SIZE(qphy->vregs), qphy->vregs); | 
|  | reset_control_assert(qphy->phy_reset); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct phy_ops qcom_pcie2_ops = { | 
|  | .init = qcom_pcie2_phy_init, | 
|  | .power_on = qcom_pcie2_phy_power_on, | 
|  | .power_off = qcom_pcie2_phy_power_off, | 
|  | .exit = qcom_pcie2_phy_exit, | 
|  | .owner = THIS_MODULE, | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Register a fixed rate pipe clock. | 
|  | * | 
|  | * The <s>_pipe_clksrc generated by PHY goes to the GCC that gate | 
|  | * controls it. The <s>_pipe_clk coming out of the GCC is requested | 
|  | * by the PHY driver for its operations. | 
|  | * We register the <s>_pipe_clksrc here. The gcc driver takes care | 
|  | * of assigning this <s>_pipe_clksrc as parent to <s>_pipe_clk. | 
|  | * Below picture shows this relationship. | 
|  | * | 
|  | *         +---------------+ | 
|  | *         |   PHY block   |<<---------------------------------------+ | 
|  | *         |               |                                         | | 
|  | *         |   +-------+   |                   +-----+               | | 
|  | *   I/P---^-->|  PLL  |---^--->pipe_clksrc--->| GCC |--->pipe_clk---+ | 
|  | *    clk  |   +-------+   |                   +-----+ | 
|  | *         +---------------+ | 
|  | */ | 
|  | static int phy_pipe_clksrc_register(struct qcom_phy *qphy) | 
|  | { | 
|  | struct device_node *np = qphy->dev->of_node; | 
|  | struct clk_fixed_rate *fixed; | 
|  | struct clk_init_data init = { }; | 
|  | int ret; | 
|  |  | 
|  | ret = of_property_read_string(np, "clock-output-names", &init.name); | 
|  | if (ret) { | 
|  | dev_err(qphy->dev, "%s: No clock-output-names\n", np->name); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | fixed = devm_kzalloc(qphy->dev, sizeof(*fixed), GFP_KERNEL); | 
|  | if (!fixed) | 
|  | return -ENOMEM; | 
|  |  | 
|  | init.ops = &clk_fixed_rate_ops; | 
|  |  | 
|  | /* controllers using QMP phys use 250MHz pipe clock interface */ | 
|  | fixed->fixed_rate = 250000000; | 
|  | fixed->hw.init = &init; | 
|  |  | 
|  | return devm_clk_hw_register(qphy->dev, &fixed->hw); | 
|  | } | 
|  |  | 
|  | static int qcom_pcie2_phy_probe(struct platform_device *pdev) | 
|  | { | 
|  | struct phy_provider *phy_provider; | 
|  | struct qcom_phy *qphy; | 
|  | struct resource *res; | 
|  | struct device *dev = &pdev->dev; | 
|  | struct phy *phy; | 
|  | int ret; | 
|  |  | 
|  | qphy = devm_kzalloc(dev, sizeof(*qphy), GFP_KERNEL); | 
|  | if (!qphy) | 
|  | return -ENOMEM; | 
|  |  | 
|  | qphy->dev = dev; | 
|  |  | 
|  | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | 
|  | qphy->base = devm_ioremap_resource(dev, res); | 
|  | if (IS_ERR(qphy->base)) | 
|  | return PTR_ERR(qphy->base); | 
|  |  | 
|  | ret = phy_pipe_clksrc_register(qphy); | 
|  | if (ret) { | 
|  | dev_err(dev, "failed to register pipe_clk\n"); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | qphy->vregs[0].supply = "vdda-vp"; | 
|  | qphy->vregs[1].supply = "vdda-vph"; | 
|  | ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(qphy->vregs), qphy->vregs); | 
|  | if (ret < 0) | 
|  | return ret; | 
|  |  | 
|  | qphy->pipe_clk = devm_clk_get(dev, NULL); | 
|  | if (IS_ERR(qphy->pipe_clk)) { | 
|  | dev_err(dev, "failed to acquire pipe clock\n"); | 
|  | return PTR_ERR(qphy->pipe_clk); | 
|  | } | 
|  |  | 
|  | qphy->phy_reset = devm_reset_control_get_exclusive(dev, "phy"); | 
|  | if (IS_ERR(qphy->phy_reset)) { | 
|  | dev_err(dev, "failed to acquire phy reset\n"); | 
|  | return PTR_ERR(qphy->phy_reset); | 
|  | } | 
|  |  | 
|  | qphy->pipe_reset = devm_reset_control_get_exclusive(dev, "pipe"); | 
|  | if (IS_ERR(qphy->pipe_reset)) { | 
|  | dev_err(dev, "failed to acquire pipe reset\n"); | 
|  | return PTR_ERR(qphy->pipe_reset); | 
|  | } | 
|  |  | 
|  | phy = devm_phy_create(dev, dev->of_node, &qcom_pcie2_ops); | 
|  | if (IS_ERR(phy)) { | 
|  | dev_err(dev, "failed to create phy\n"); | 
|  | return PTR_ERR(phy); | 
|  | } | 
|  |  | 
|  | phy_set_drvdata(phy, qphy); | 
|  |  | 
|  | phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); | 
|  | if (IS_ERR(phy_provider)) | 
|  | dev_err(dev, "failed to register phy provider\n"); | 
|  |  | 
|  | return PTR_ERR_OR_ZERO(phy_provider); | 
|  | } | 
|  |  | 
|  | static const struct of_device_id qcom_pcie2_phy_match_table[] = { | 
|  | { .compatible = "qcom,pcie2-phy" }, | 
|  | {} | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(of, qcom_pcie2_phy_match_table); | 
|  |  | 
|  | static struct platform_driver qcom_pcie2_phy_driver = { | 
|  | .probe = qcom_pcie2_phy_probe, | 
|  | .driver = { | 
|  | .name = "phy-qcom-pcie2", | 
|  | .of_match_table = qcom_pcie2_phy_match_table, | 
|  | }, | 
|  | }; | 
|  |  | 
|  | module_platform_driver(qcom_pcie2_phy_driver); | 
|  |  | 
|  | MODULE_DESCRIPTION("Qualcomm PCIe PHY driver"); | 
|  | MODULE_LICENSE("GPL v2"); |