xref: /openbmc/linux/drivers/usb/cdns3/cdns3-imx.c (revision 9123e3a7)
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * cdns3-imx.c - NXP i.MX specific Glue layer for Cadence USB Controller
4  *
5  * Copyright (C) 2019 NXP
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/iopoll.h>
18 
19 #define USB3_CORE_CTRL1    0x00
20 #define USB3_CORE_CTRL2    0x04
21 #define USB3_INT_REG       0x08
22 #define USB3_CORE_STATUS   0x0c
23 #define XHCI_DEBUG_LINK_ST 0x10
24 #define XHCI_DEBUG_BUS     0x14
25 #define USB3_SSPHY_CTRL1   0x40
26 #define USB3_SSPHY_CTRL2   0x44
27 #define USB3_SSPHY_STATUS  0x4c
28 #define USB2_PHY_CTRL1     0x50
29 #define USB2_PHY_CTRL2     0x54
30 #define USB2_PHY_STATUS    0x5c
31 
32 /* Register bits definition */
33 
34 /* USB3_CORE_CTRL1 */
35 #define SW_RESET_MASK	(0x3f << 26)
36 #define PWR_SW_RESET	BIT(31)
37 #define APB_SW_RESET	BIT(30)
38 #define AXI_SW_RESET	BIT(29)
39 #define RW_SW_RESET	BIT(28)
40 #define PHY_SW_RESET	BIT(27)
41 #define PHYAHB_SW_RESET	BIT(26)
42 #define ALL_SW_RESET	(PWR_SW_RESET | APB_SW_RESET | AXI_SW_RESET | \
43 		RW_SW_RESET | PHY_SW_RESET | PHYAHB_SW_RESET)
44 #define OC_DISABLE	BIT(9)
45 #define MDCTRL_CLK_SEL	BIT(7)
46 #define MODE_STRAP_MASK	(0x7)
47 #define DEV_MODE	(1 << 2)
48 #define HOST_MODE	(1 << 1)
49 #define OTG_MODE	(1 << 0)
50 
51 /* USB3_INT_REG */
52 #define CLK_125_REQ	BIT(29)
53 #define LPM_CLK_REQ	BIT(28)
54 #define DEVU3_WAEKUP_EN	BIT(14)
55 #define OTG_WAKEUP_EN	BIT(12)
56 #define DEV_INT_EN (3 << 8) /* DEV INT b9:8 */
57 #define HOST_INT1_EN (1 << 0) /* HOST INT b7:0 */
58 
59 /* USB3_CORE_STATUS */
60 #define MDCTRL_CLK_STATUS	BIT(15)
61 #define DEV_POWER_ON_READY	BIT(13)
62 #define HOST_POWER_ON_READY	BIT(12)
63 
64 /* USB3_SSPHY_STATUS */
65 #define CLK_VALID_MASK		(0x3f << 26)
66 #define CLK_VALID_COMPARE_BITS	(0xf << 28)
67 #define PHY_REFCLK_REQ		(1 << 0)
68 
69 struct cdns_imx {
70 	struct device *dev;
71 	void __iomem *noncore;
72 	struct clk_bulk_data *clks;
73 	int num_clks;
74 };
75 
76 static inline u32 cdns_imx_readl(struct cdns_imx *data, u32 offset)
77 {
78 	return readl(data->noncore + offset);
79 }
80 
81 static inline void cdns_imx_writel(struct cdns_imx *data, u32 offset, u32 value)
82 {
83 	writel(value, data->noncore + offset);
84 }
85 
86 static const struct clk_bulk_data imx_cdns3_core_clks[] = {
87 	{ .id = "usb3_lpm_clk" },
88 	{ .id = "usb3_bus_clk" },
89 	{ .id = "usb3_aclk" },
90 	{ .id = "usb3_ipg_clk" },
91 	{ .id = "usb3_core_pclk" },
92 };
93 
94 static int cdns_imx_noncore_init(struct cdns_imx *data)
95 {
96 	u32 value;
97 	int ret;
98 	struct device *dev = data->dev;
99 
100 	cdns_imx_writel(data, USB3_SSPHY_STATUS, CLK_VALID_MASK);
101 	udelay(1);
102 	ret = readl_poll_timeout(data->noncore + USB3_SSPHY_STATUS, value,
103 		(value & CLK_VALID_COMPARE_BITS) == CLK_VALID_COMPARE_BITS,
104 		10, 100000);
105 	if (ret) {
106 		dev_err(dev, "wait clkvld timeout\n");
107 		return ret;
108 	}
109 
110 	value = cdns_imx_readl(data, USB3_CORE_CTRL1);
111 	value |= ALL_SW_RESET;
112 	cdns_imx_writel(data, USB3_CORE_CTRL1, value);
113 	udelay(1);
114 
115 	value = cdns_imx_readl(data, USB3_CORE_CTRL1);
116 	value = (value & ~MODE_STRAP_MASK) | OTG_MODE | OC_DISABLE;
117 	cdns_imx_writel(data, USB3_CORE_CTRL1, value);
118 
119 	value = cdns_imx_readl(data, USB3_INT_REG);
120 	value |= HOST_INT1_EN | DEV_INT_EN;
121 	cdns_imx_writel(data, USB3_INT_REG, value);
122 
123 	value = cdns_imx_readl(data, USB3_CORE_CTRL1);
124 	value &= ~ALL_SW_RESET;
125 	cdns_imx_writel(data, USB3_CORE_CTRL1, value);
126 	return ret;
127 }
128 
129 static int cdns_imx_probe(struct platform_device *pdev)
130 {
131 	struct device *dev = &pdev->dev;
132 	struct device_node *node = dev->of_node;
133 	struct cdns_imx *data;
134 	int ret;
135 
136 	if (!node)
137 		return -ENODEV;
138 
139 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
140 	if (!data)
141 		return -ENOMEM;
142 
143 	platform_set_drvdata(pdev, data);
144 	data->dev = dev;
145 	data->noncore = devm_platform_ioremap_resource(pdev, 0);
146 	if (IS_ERR(data->noncore)) {
147 		dev_err(dev, "can't map IOMEM resource\n");
148 		return PTR_ERR(data->noncore);
149 	}
150 
151 	data->num_clks = ARRAY_SIZE(imx_cdns3_core_clks);
152 	data->clks = (struct clk_bulk_data *)imx_cdns3_core_clks;
153 	ret = devm_clk_bulk_get(dev, data->num_clks, data->clks);
154 	if (ret)
155 		return ret;
156 
157 	ret = clk_bulk_prepare_enable(data->num_clks, data->clks);
158 	if (ret)
159 		return ret;
160 
161 	ret = cdns_imx_noncore_init(data);
162 	if (ret)
163 		goto err;
164 
165 	ret = of_platform_populate(node, NULL, NULL, dev);
166 	if (ret) {
167 		dev_err(dev, "failed to create children: %d\n", ret);
168 		goto err;
169 	}
170 
171 	return ret;
172 
173 err:
174 	clk_bulk_disable_unprepare(data->num_clks, data->clks);
175 	return ret;
176 }
177 
178 static int cdns_imx_remove_core(struct device *dev, void *data)
179 {
180 	struct platform_device *pdev = to_platform_device(dev);
181 
182 	platform_device_unregister(pdev);
183 
184 	return 0;
185 }
186 
187 static int cdns_imx_remove(struct platform_device *pdev)
188 {
189 	struct device *dev = &pdev->dev;
190 
191 	device_for_each_child(dev, NULL, cdns_imx_remove_core);
192 	platform_set_drvdata(pdev, NULL);
193 
194 	return 0;
195 }
196 
197 static const struct of_device_id cdns_imx_of_match[] = {
198 	{ .compatible = "fsl,imx8qm-usb3", },
199 	{},
200 };
201 MODULE_DEVICE_TABLE(of, cdns_imx_of_match);
202 
203 static struct platform_driver cdns_imx_driver = {
204 	.probe		= cdns_imx_probe,
205 	.remove		= cdns_imx_remove,
206 	.driver		= {
207 		.name	= "cdns3-imx",
208 		.of_match_table	= cdns_imx_of_match,
209 	},
210 };
211 module_platform_driver(cdns_imx_driver);
212 
213 MODULE_ALIAS("platform:cdns3-imx");
214 MODULE_AUTHOR("Peter Chen <peter.chen@nxp.com>");
215 MODULE_LICENSE("GPL v2");
216 MODULE_DESCRIPTION("Cadence USB3 i.MX Glue Layer");
217