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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Copyright 2021 NXP4 */5 6#include <linux/bitfield.h>7#include <linux/clk.h>8#include <linux/delay.h>9#include <linux/io.h>10#include <linux/iopoll.h>11#include <linux/mfd/syscon.h>12#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/phy/phy.h>16#include <linux/platform_device.h>17#include <linux/regmap.h>18#include <linux/reset.h>19 20#include <dt-bindings/phy/phy-imx8-pcie.h>21 22#define IMX8MM_PCIE_PHY_CMN_REG061	0x18423#define  ANA_PLL_CLK_OUT_TO_EXT_IO_EN	BIT(0)24#define IMX8MM_PCIE_PHY_CMN_REG062	0x18825#define  ANA_PLL_CLK_OUT_TO_EXT_IO_SEL	BIT(3)26#define IMX8MM_PCIE_PHY_CMN_REG063	0x18C27#define  AUX_PLL_REFCLK_SEL_SYS_PLL	GENMASK(7, 6)28#define IMX8MM_PCIE_PHY_CMN_REG064	0x19029#define  ANA_AUX_RX_TX_SEL_TX		BIT(7)30#define  ANA_AUX_RX_TERM_GND_EN		BIT(3)31#define  ANA_AUX_TX_TERM		BIT(2)32#define IMX8MM_PCIE_PHY_CMN_REG065	0x19433#define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))34#define  ANA_AUX_TX_LVL			GENMASK(3, 0)35#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D436#define  ANA_PLL_DONE			0x337#define PCIE_PHY_TRSV_REG5		0x41438#define PCIE_PHY_TRSV_REG6		0x41839 40#define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)41#define IMX8MM_GPR_PCIE_REF_CLK_PLL	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)42#define IMX8MM_GPR_PCIE_REF_CLK_EXT	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x2)43#define IMX8MM_GPR_PCIE_AUX_EN		BIT(19)44#define IMX8MM_GPR_PCIE_CMN_RST		BIT(18)45#define IMX8MM_GPR_PCIE_POWER_OFF	BIT(17)46#define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)47#define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)48 49enum imx8_pcie_phy_type {50	IMX8MM,51	IMX8MP,52};53 54struct imx8_pcie_phy_drvdata {55	const	char			*gpr;56	enum	imx8_pcie_phy_type	variant;57};58 59struct imx8_pcie_phy {60	void __iomem		*base;61	struct clk		*clk;62	struct phy		*phy;63	struct regmap		*iomuxc_gpr;64	struct reset_control	*perst;65	struct reset_control	*reset;66	u32			refclk_pad_mode;67	u32			tx_deemph_gen1;68	u32			tx_deemph_gen2;69	bool			clkreq_unused;70	const struct imx8_pcie_phy_drvdata	*drvdata;71};72 73static int imx8_pcie_phy_power_on(struct phy *phy)74{75	int ret;76	u32 val, pad_mode;77	struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);78 79	pad_mode = imx8_phy->refclk_pad_mode;80	switch (imx8_phy->drvdata->variant) {81	case IMX8MM:82		reset_control_assert(imx8_phy->reset);83 84		/* Tune PHY de-emphasis setting to pass PCIe compliance. */85		if (imx8_phy->tx_deemph_gen1)86			writel(imx8_phy->tx_deemph_gen1,87			       imx8_phy->base + PCIE_PHY_TRSV_REG5);88		if (imx8_phy->tx_deemph_gen2)89			writel(imx8_phy->tx_deemph_gen2,90			       imx8_phy->base + PCIE_PHY_TRSV_REG6);91		break;92	case IMX8MP: /* Do nothing. */93		break;94	}95 96	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||97	    pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {98		/* Configure the pad as input */99		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);100		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,101		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);102	} else {103		/* Configure the PHY to output the refclock via pad */104		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,105		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);106	}107 108	if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT ||109	    pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {110		/* Source clock from SoC internal PLL */111		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,112		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);113		if (imx8_phy->drvdata->variant != IMX8MM) {114			writel(AUX_PLL_REFCLK_SEL_SYS_PLL,115			       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);116		}117		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;118		writel(val | ANA_AUX_RX_TERM_GND_EN,119		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);120		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,121		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);122	}123 124	/* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */125	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,126			   IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,127			   imx8_phy->clkreq_unused ?128			   0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);129	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,130			   IMX8MM_GPR_PCIE_AUX_EN,131			   IMX8MM_GPR_PCIE_AUX_EN);132	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,133			   IMX8MM_GPR_PCIE_POWER_OFF, 0);134	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,135			   IMX8MM_GPR_PCIE_SSC_EN, 0);136 137	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,138			   IMX8MM_GPR_PCIE_REF_CLK_SEL,139			   pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?140			   IMX8MM_GPR_PCIE_REF_CLK_EXT :141			   IMX8MM_GPR_PCIE_REF_CLK_PLL);142	usleep_range(100, 200);143 144	switch (imx8_phy->drvdata->variant) {145	case IMX8MP:146		reset_control_deassert(imx8_phy->perst);147		fallthrough;148	case IMX8MM:149		reset_control_deassert(imx8_phy->reset);150		usleep_range(200, 500);151		break;152	}153 154	/* Do the PHY common block reset */155	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,156			   IMX8MM_GPR_PCIE_CMN_RST,157			   IMX8MM_GPR_PCIE_CMN_RST);158 159	/* Polling to check the phy is ready or not. */160	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075,161				 val, val == ANA_PLL_DONE, 10, 20000);162	return ret;163}164 165static int imx8_pcie_phy_init(struct phy *phy)166{167	struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);168 169	return clk_prepare_enable(imx8_phy->clk);170}171 172static int imx8_pcie_phy_exit(struct phy *phy)173{174	struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);175 176	clk_disable_unprepare(imx8_phy->clk);177 178	return 0;179}180 181static const struct phy_ops imx8_pcie_phy_ops = {182	.init		= imx8_pcie_phy_init,183	.exit		= imx8_pcie_phy_exit,184	.power_on	= imx8_pcie_phy_power_on,185	.owner		= THIS_MODULE,186};187 188static const struct imx8_pcie_phy_drvdata imx8mm_drvdata = {189	.gpr = "fsl,imx8mm-iomuxc-gpr",190	.variant = IMX8MM,191};192 193static const struct imx8_pcie_phy_drvdata imx8mp_drvdata = {194	.gpr = "fsl,imx8mp-iomuxc-gpr",195	.variant = IMX8MP,196};197 198static const struct of_device_id imx8_pcie_phy_of_match[] = {199	{.compatible = "fsl,imx8mm-pcie-phy", .data = &imx8mm_drvdata, },200	{.compatible = "fsl,imx8mp-pcie-phy", .data = &imx8mp_drvdata, },201	{ },202};203MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);204 205static int imx8_pcie_phy_probe(struct platform_device *pdev)206{207	struct phy_provider *phy_provider;208	struct device *dev = &pdev->dev;209	struct device_node *np = dev->of_node;210	struct imx8_pcie_phy *imx8_phy;211 212	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);213	if (!imx8_phy)214		return -ENOMEM;215 216	imx8_phy->drvdata = of_device_get_match_data(dev);217 218	/* get PHY refclk pad mode */219	of_property_read_u32(np, "fsl,refclk-pad-mode",220			     &imx8_phy->refclk_pad_mode);221 222	if (of_property_read_u32(np, "fsl,tx-deemph-gen1",223				 &imx8_phy->tx_deemph_gen1))224		imx8_phy->tx_deemph_gen1 = 0;225 226	if (of_property_read_u32(np, "fsl,tx-deemph-gen2",227				 &imx8_phy->tx_deemph_gen2))228		imx8_phy->tx_deemph_gen2 = 0;229 230	if (of_property_read_bool(np, "fsl,clkreq-unsupported"))231		imx8_phy->clkreq_unused = true;232	else233		imx8_phy->clkreq_unused = false;234 235	imx8_phy->clk = devm_clk_get(dev, "ref");236	if (IS_ERR(imx8_phy->clk)) {237		dev_err(dev, "failed to get imx pcie phy clock\n");238		return PTR_ERR(imx8_phy->clk);239	}240 241	/* Grab GPR config register range */242	imx8_phy->iomuxc_gpr =243		 syscon_regmap_lookup_by_compatible(imx8_phy->drvdata->gpr);244	if (IS_ERR(imx8_phy->iomuxc_gpr)) {245		dev_err(dev, "unable to find iomuxc registers\n");246		return PTR_ERR(imx8_phy->iomuxc_gpr);247	}248 249	imx8_phy->reset = devm_reset_control_get_exclusive(dev, "pciephy");250	if (IS_ERR(imx8_phy->reset)) {251		dev_err(dev, "Failed to get PCIEPHY reset control\n");252		return PTR_ERR(imx8_phy->reset);253	}254 255	if (imx8_phy->drvdata->variant == IMX8MP) {256		imx8_phy->perst =257			devm_reset_control_get_exclusive(dev, "perst");258		if (IS_ERR(imx8_phy->perst))259			return dev_err_probe(dev, PTR_ERR(imx8_phy->perst),260				      "Failed to get PCIE PHY PERST control\n");261	}262 263	imx8_phy->base = devm_platform_ioremap_resource(pdev, 0);264	if (IS_ERR(imx8_phy->base))265		return PTR_ERR(imx8_phy->base);266 267	imx8_phy->phy = devm_phy_create(dev, NULL, &imx8_pcie_phy_ops);268	if (IS_ERR(imx8_phy->phy))269		return PTR_ERR(imx8_phy->phy);270 271	phy_set_drvdata(imx8_phy->phy, imx8_phy);272 273	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);274 275	return PTR_ERR_OR_ZERO(phy_provider);276}277 278static struct platform_driver imx8_pcie_phy_driver = {279	.probe	= imx8_pcie_phy_probe,280	.driver = {281		.name	= "imx8-pcie-phy",282		.of_match_table	= imx8_pcie_phy_of_match,283	}284};285module_platform_driver(imx8_pcie_phy_driver);286 287MODULE_DESCRIPTION("FSL IMX8 PCIE PHY driver");288MODULE_LICENSE("GPL v2");289