1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * cdns3-ti.c - TI specific Glue layer for Cadence USB Controller 4 * 5 * Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com 6 */ 7 8 #include <linux/bits.h> 9 #include <linux/clk.h> 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/interrupt.h> 13 #include <linux/platform_device.h> 14 #include <linux/dma-mapping.h> 15 #include <linux/io.h> 16 #include <linux/of_platform.h> 17 #include <linux/pm_runtime.h> 18 19 /* USB Wrapper register offsets */ 20 #define USBSS_PID 0x0 21 #define USBSS_W1 0x4 22 #define USBSS_STATIC_CONFIG 0x8 23 #define USBSS_PHY_TEST 0xc 24 #define USBSS_DEBUG_CTRL 0x10 25 #define USBSS_DEBUG_INFO 0x14 26 #define USBSS_DEBUG_LINK_STATE 0x18 27 #define USBSS_DEVICE_CTRL 0x1c 28 29 /* Wrapper 1 register bits */ 30 #define USBSS_W1_PWRUP_RST BIT(0) 31 #define USBSS_W1_OVERCURRENT_SEL BIT(8) 32 #define USBSS_W1_MODESTRAP_SEL BIT(9) 33 #define USBSS_W1_OVERCURRENT BIT(16) 34 #define USBSS_W1_MODESTRAP_MASK GENMASK(18, 17) 35 #define USBSS_W1_MODESTRAP_SHIFT 17 36 #define USBSS_W1_USB2_ONLY BIT(19) 37 38 /* Static config register bits */ 39 #define USBSS1_STATIC_PLL_REF_SEL_MASK GENMASK(8, 5) 40 #define USBSS1_STATIC_PLL_REF_SEL_SHIFT 5 41 #define USBSS1_STATIC_LOOPBACK_MODE_MASK GENMASK(4, 3) 42 #define USBSS1_STATIC_LOOPBACK_MODE_SHIFT 3 43 #define USBSS1_STATIC_VBUS_SEL_MASK GENMASK(2, 1) 44 #define USBSS1_STATIC_VBUS_SEL_SHIFT 1 45 #define USBSS1_STATIC_LANE_REVERSE BIT(0) 46 47 /* Modestrap modes */ 48 enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE, 49 USBSS_MODESTRAP_MODE_HOST, 50 USBSS_MODESTRAP_MODE_PERIPHERAL}; 51 52 struct cdns_ti { 53 struct device *dev; 54 void __iomem *usbss; 55 unsigned usb2_only:1; 56 unsigned vbus_divider:1; 57 struct clk *usb2_refclk; 58 struct clk *lpm_clk; 59 }; 60 61 static const int cdns_ti_rate_table[] = { /* in KHZ */ 62 9600, 63 10000, 64 12000, 65 19200, 66 20000, 67 24000, 68 25000, 69 26000, 70 38400, 71 40000, 72 58000, 73 50000, 74 52000, 75 }; 76 77 static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset) 78 { 79 return readl(data->usbss + offset); 80 } 81 82 static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value) 83 { 84 writel(value, data->usbss + offset); 85 } 86 87 static int cdns_ti_probe(struct platform_device *pdev) 88 { 89 struct device *dev = &pdev->dev; 90 struct device_node *node = pdev->dev.of_node; 91 struct cdns_ti *data; 92 int error; 93 u32 reg; 94 int rate_code, i; 95 unsigned long rate; 96 97 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 98 if (!data) 99 return -ENOMEM; 100 101 platform_set_drvdata(pdev, data); 102 103 data->dev = dev; 104 105 data->usbss = devm_platform_ioremap_resource(pdev, 0); 106 if (IS_ERR(data->usbss)) { 107 dev_err(dev, "can't map IOMEM resource\n"); 108 return PTR_ERR(data->usbss); 109 } 110 111 data->usb2_refclk = devm_clk_get(dev, "ref"); 112 if (IS_ERR(data->usb2_refclk)) { 113 dev_err(dev, "can't get usb2_refclk\n"); 114 return PTR_ERR(data->usb2_refclk); 115 } 116 117 data->lpm_clk = devm_clk_get(dev, "lpm"); 118 if (IS_ERR(data->lpm_clk)) { 119 dev_err(dev, "can't get lpm_clk\n"); 120 return PTR_ERR(data->lpm_clk); 121 } 122 123 rate = clk_get_rate(data->usb2_refclk); 124 rate /= 1000; /* To KHz */ 125 for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) { 126 if (cdns_ti_rate_table[i] == rate) 127 break; 128 } 129 130 if (i == ARRAY_SIZE(cdns_ti_rate_table)) { 131 dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate); 132 return -EINVAL; 133 } 134 135 rate_code = i; 136 137 pm_runtime_enable(dev); 138 error = pm_runtime_get_sync(dev); 139 if (error < 0) { 140 dev_err(dev, "pm_runtime_get_sync failed: %d\n", error); 141 goto err; 142 } 143 144 /* assert RESET */ 145 reg = cdns_ti_readl(data, USBSS_W1); 146 reg &= ~USBSS_W1_PWRUP_RST; 147 cdns_ti_writel(data, USBSS_W1, reg); 148 149 /* set static config */ 150 reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG); 151 reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK; 152 reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT; 153 154 reg &= ~USBSS1_STATIC_VBUS_SEL_MASK; 155 data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider"); 156 if (data->vbus_divider) 157 reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT; 158 159 cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg); 160 reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG); 161 162 /* set USB2_ONLY mode if requested */ 163 reg = cdns_ti_readl(data, USBSS_W1); 164 data->usb2_only = device_property_read_bool(dev, "ti,usb2-only"); 165 if (data->usb2_only) 166 reg |= USBSS_W1_USB2_ONLY; 167 168 /* set default modestrap */ 169 reg |= USBSS_W1_MODESTRAP_SEL; 170 reg &= ~USBSS_W1_MODESTRAP_MASK; 171 reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT; 172 cdns_ti_writel(data, USBSS_W1, reg); 173 174 /* de-assert RESET */ 175 reg |= USBSS_W1_PWRUP_RST; 176 cdns_ti_writel(data, USBSS_W1, reg); 177 178 error = of_platform_populate(node, NULL, NULL, dev); 179 if (error) { 180 dev_err(dev, "failed to create children: %d\n", error); 181 goto err; 182 } 183 184 return 0; 185 186 err: 187 pm_runtime_put_sync(data->dev); 188 pm_runtime_disable(data->dev); 189 190 return error; 191 } 192 193 static int cdns_ti_remove_core(struct device *dev, void *c) 194 { 195 struct platform_device *pdev = to_platform_device(dev); 196 197 platform_device_unregister(pdev); 198 199 return 0; 200 } 201 202 static void cdns_ti_remove(struct platform_device *pdev) 203 { 204 struct device *dev = &pdev->dev; 205 206 device_for_each_child(dev, NULL, cdns_ti_remove_core); 207 pm_runtime_put_sync(dev); 208 pm_runtime_disable(dev); 209 210 platform_set_drvdata(pdev, NULL); 211 } 212 213 static const struct of_device_id cdns_ti_of_match[] = { 214 { .compatible = "ti,j721e-usb", }, 215 { .compatible = "ti,am64-usb", }, 216 {}, 217 }; 218 MODULE_DEVICE_TABLE(of, cdns_ti_of_match); 219 220 static struct platform_driver cdns_ti_driver = { 221 .probe = cdns_ti_probe, 222 .remove_new = cdns_ti_remove, 223 .driver = { 224 .name = "cdns3-ti", 225 .of_match_table = cdns_ti_of_match, 226 }, 227 }; 228 229 module_platform_driver(cdns_ti_driver); 230 231 MODULE_ALIAS("platform:cdns3-ti"); 232 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); 233 MODULE_LICENSE("GPL v2"); 234 MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer"); 235