1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright 2021 NXP 4 */ 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_device.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 0x184 23 #define ANA_PLL_CLK_OUT_TO_EXT_IO_EN BIT(0) 24 #define IMX8MM_PCIE_PHY_CMN_REG062 0x188 25 #define ANA_PLL_CLK_OUT_TO_EXT_IO_SEL BIT(3) 26 #define IMX8MM_PCIE_PHY_CMN_REG063 0x18C 27 #define AUX_PLL_REFCLK_SEL_SYS_PLL GENMASK(7, 6) 28 #define IMX8MM_PCIE_PHY_CMN_REG064 0x190 29 #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 0x194 33 #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 0x1D4 36 #define ANA_PLL_DONE 0x3 37 #define PCIE_PHY_TRSV_REG5 0x414 38 #define PCIE_PHY_TRSV_REG6 0x418 39 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 49 enum imx8_pcie_phy_type { 50 IMX8MM, 51 IMX8MP, 52 }; 53 54 struct imx8_pcie_phy_drvdata { 55 const char *gpr; 56 enum imx8_pcie_phy_type variant; 57 }; 58 59 struct 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 73 static 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 writel(AUX_PLL_REFCLK_SEL_SYS_PLL, 114 imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063); 115 val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM; 116 writel(val | ANA_AUX_RX_TERM_GND_EN, 117 imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064); 118 writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL, 119 imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065); 120 } 121 122 /* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */ 123 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 124 IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE, 125 imx8_phy->clkreq_unused ? 126 0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE); 127 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 128 IMX8MM_GPR_PCIE_AUX_EN, 129 IMX8MM_GPR_PCIE_AUX_EN); 130 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 131 IMX8MM_GPR_PCIE_POWER_OFF, 0); 132 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 133 IMX8MM_GPR_PCIE_SSC_EN, 0); 134 135 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 136 IMX8MM_GPR_PCIE_REF_CLK_SEL, 137 pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ? 138 IMX8MM_GPR_PCIE_REF_CLK_EXT : 139 IMX8MM_GPR_PCIE_REF_CLK_PLL); 140 usleep_range(100, 200); 141 142 /* Do the PHY common block reset */ 143 regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14, 144 IMX8MM_GPR_PCIE_CMN_RST, 145 IMX8MM_GPR_PCIE_CMN_RST); 146 147 switch (imx8_phy->drvdata->variant) { 148 case IMX8MP: 149 reset_control_deassert(imx8_phy->perst); 150 fallthrough; 151 case IMX8MM: 152 reset_control_deassert(imx8_phy->reset); 153 usleep_range(200, 500); 154 break; 155 } 156 157 /* Polling to check the phy is ready or not. */ 158 ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075, 159 val, val == ANA_PLL_DONE, 10, 20000); 160 return ret; 161 } 162 163 static int imx8_pcie_phy_init(struct phy *phy) 164 { 165 struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy); 166 167 return clk_prepare_enable(imx8_phy->clk); 168 } 169 170 static int imx8_pcie_phy_exit(struct phy *phy) 171 { 172 struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy); 173 174 clk_disable_unprepare(imx8_phy->clk); 175 176 return 0; 177 } 178 179 static const struct phy_ops imx8_pcie_phy_ops = { 180 .init = imx8_pcie_phy_init, 181 .exit = imx8_pcie_phy_exit, 182 .power_on = imx8_pcie_phy_power_on, 183 .owner = THIS_MODULE, 184 }; 185 186 static const struct imx8_pcie_phy_drvdata imx8mm_drvdata = { 187 .gpr = "fsl,imx8mm-iomuxc-gpr", 188 .variant = IMX8MM, 189 }; 190 191 static const struct imx8_pcie_phy_drvdata imx8mp_drvdata = { 192 .gpr = "fsl,imx8mp-iomuxc-gpr", 193 .variant = IMX8MP, 194 }; 195 196 static const struct of_device_id imx8_pcie_phy_of_match[] = { 197 {.compatible = "fsl,imx8mm-pcie-phy", .data = &imx8mm_drvdata, }, 198 {.compatible = "fsl,imx8mp-pcie-phy", .data = &imx8mp_drvdata, }, 199 { }, 200 }; 201 MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match); 202 203 static int imx8_pcie_phy_probe(struct platform_device *pdev) 204 { 205 struct phy_provider *phy_provider; 206 struct device *dev = &pdev->dev; 207 struct device_node *np = dev->of_node; 208 struct imx8_pcie_phy *imx8_phy; 209 struct resource *res; 210 211 imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL); 212 if (!imx8_phy) 213 return -ENOMEM; 214 215 imx8_phy->drvdata = of_device_get_match_data(dev); 216 217 /* get PHY refclk pad mode */ 218 of_property_read_u32(np, "fsl,refclk-pad-mode", 219 &imx8_phy->refclk_pad_mode); 220 221 if (of_property_read_u32(np, "fsl,tx-deemph-gen1", 222 &imx8_phy->tx_deemph_gen1)) 223 imx8_phy->tx_deemph_gen1 = 0; 224 225 if (of_property_read_u32(np, "fsl,tx-deemph-gen2", 226 &imx8_phy->tx_deemph_gen2)) 227 imx8_phy->tx_deemph_gen2 = 0; 228 229 if (of_property_read_bool(np, "fsl,clkreq-unsupported")) 230 imx8_phy->clkreq_unused = true; 231 else 232 imx8_phy->clkreq_unused = false; 233 234 imx8_phy->clk = devm_clk_get(dev, "ref"); 235 if (IS_ERR(imx8_phy->clk)) { 236 dev_err(dev, "failed to get imx pcie phy clock\n"); 237 return PTR_ERR(imx8_phy->clk); 238 } 239 240 /* Grab GPR config register range */ 241 imx8_phy->iomuxc_gpr = 242 syscon_regmap_lookup_by_compatible(imx8_phy->drvdata->gpr); 243 if (IS_ERR(imx8_phy->iomuxc_gpr)) { 244 dev_err(dev, "unable to find iomuxc registers\n"); 245 return PTR_ERR(imx8_phy->iomuxc_gpr); 246 } 247 248 imx8_phy->reset = devm_reset_control_get_exclusive(dev, "pciephy"); 249 if (IS_ERR(imx8_phy->reset)) { 250 dev_err(dev, "Failed to get PCIEPHY reset control\n"); 251 return PTR_ERR(imx8_phy->reset); 252 } 253 254 if (imx8_phy->drvdata->variant == IMX8MP) { 255 imx8_phy->perst = 256 devm_reset_control_get_exclusive(dev, "perst"); 257 if (IS_ERR(imx8_phy->perst)) 258 return dev_err_probe(dev, PTR_ERR(imx8_phy->perst), 259 "Failed to get PCIE PHY PERST control\n"); 260 } 261 262 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 263 imx8_phy->base = devm_ioremap_resource(dev, res); 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 } 277 278 static 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 }; 285 module_platform_driver(imx8_pcie_phy_driver); 286 287 MODULE_DESCRIPTION("FSL IMX8 PCIE PHY driver"); 288 MODULE_LICENSE("GPL v2"); 289