1 /*
2  * STiH407 family DWC3 specific Glue layer
3  *
4  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
5  * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <asm/io.h>
12 #include <dm.h>
13 #include <errno.h>
14 #include <fdtdec.h>
15 #include <libfdt.h>
16 #include <dm/lists.h>
17 #include <regmap.h>
18 #include <reset-uclass.h>
19 #include <syscon.h>
20 #include <usb.h>
21 
22 #include <linux/usb/dwc3.h>
23 #include <linux/usb/otg.h>
24 #include <dwc3-sti-glue.h>
25 
26 DECLARE_GLOBAL_DATA_PTR;
27 
28 /*
29  * struct sti_dwc3_glue_platdata - dwc3 STi glue driver private structure
30  * @syscfg_base:	addr for the glue syscfg
31  * @glue_base:		addr for the glue registers
32  * @syscfg_offset:	usb syscfg control offset
33  * @powerdown_ctl:	rest controller for powerdown signal
34  * @softreset_ctl:	reset controller for softreset signal
35  * @mode:		drd static host/device config
36  */
37 struct sti_dwc3_glue_platdata {
38 	phys_addr_t syscfg_base;
39 	phys_addr_t glue_base;
40 	phys_addr_t syscfg_offset;
41 	struct reset_ctl powerdown_ctl;
42 	struct reset_ctl softreset_ctl;
43 	enum usb_dr_mode mode;
44 };
45 
46 static int sti_dwc3_glue_drd_init(struct sti_dwc3_glue_platdata *plat)
47 {
48 	unsigned long val;
49 
50 	val = readl(plat->syscfg_base + plat->syscfg_offset);
51 
52 	val &= USB3_CONTROL_MASK;
53 
54 	switch (plat->mode) {
55 	case USB_DR_MODE_PERIPHERAL:
56 		val &= ~(USB3_DELAY_VBUSVALID
57 			| USB3_SEL_FORCE_OPMODE | USB3_FORCE_OPMODE(0x3)
58 			| USB3_SEL_FORCE_DPPULLDOWN2 | USB3_FORCE_DPPULLDOWN2
59 			| USB3_SEL_FORCE_DMPULLDOWN2 | USB3_FORCE_DMPULLDOWN2);
60 
61 		val |= USB3_DEVICE_NOT_HOST | USB3_FORCE_VBUSVALID;
62 		break;
63 
64 	case USB_DR_MODE_HOST:
65 		val &= ~(USB3_DEVICE_NOT_HOST | USB3_FORCE_VBUSVALID
66 			| USB3_SEL_FORCE_OPMODE	| USB3_FORCE_OPMODE(0x3)
67 			| USB3_SEL_FORCE_DPPULLDOWN2 | USB3_FORCE_DPPULLDOWN2
68 			| USB3_SEL_FORCE_DMPULLDOWN2 | USB3_FORCE_DMPULLDOWN2);
69 
70 		val |= USB3_DELAY_VBUSVALID;
71 		break;
72 
73 	default:
74 		pr_err("Unsupported mode of operation %d\n", plat->mode);
75 		return -EINVAL;
76 	}
77 	writel(val, plat->syscfg_base + plat->syscfg_offset);
78 
79 	return 0;
80 }
81 
82 static void sti_dwc3_glue_init(struct sti_dwc3_glue_platdata *plat)
83 {
84 	unsigned long reg;
85 
86 	reg = readl(plat->glue_base + CLKRST_CTRL);
87 
88 	reg |= AUX_CLK_EN | EXT_CFG_RESET_N | XHCI_REVISION;
89 	reg &= ~SW_PIPEW_RESET_N;
90 
91 	writel(reg, plat->glue_base + CLKRST_CTRL);
92 
93 	/* configure mux for vbus, powerpresent and bvalid signals */
94 	reg = readl(plat->glue_base + USB2_VBUS_MNGMNT_SEL1);
95 
96 	reg |= SEL_OVERRIDE_VBUSVALID(USB2_VBUS_UTMIOTG) |
97 	       SEL_OVERRIDE_POWERPRESENT(USB2_VBUS_UTMIOTG) |
98 	       SEL_OVERRIDE_BVALID(USB2_VBUS_UTMIOTG);
99 
100 	writel(reg, plat->glue_base + USB2_VBUS_MNGMNT_SEL1);
101 
102 	setbits_le32(plat->glue_base + CLKRST_CTRL, SW_PIPEW_RESET_N);
103 }
104 
105 static int sti_dwc3_glue_ofdata_to_platdata(struct udevice *dev)
106 {
107 	struct sti_dwc3_glue_platdata *plat = dev_get_platdata(dev);
108 	struct udevice *syscon;
109 	struct regmap *regmap;
110 	int ret;
111 	u32 reg[4];
112 
113 	ret = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev),
114 				   "reg", reg, ARRAY_SIZE(reg));
115 	if (ret) {
116 		pr_err("unable to find st,stih407-dwc3 reg property(%d)\n", ret);
117 		return ret;
118 	}
119 
120 	plat->glue_base = reg[0];
121 	plat->syscfg_offset = reg[2];
122 
123 	/* get corresponding syscon phandle */
124 	ret = uclass_get_device_by_phandle(UCLASS_SYSCON, dev, "st,syscfg",
125 					   &syscon);
126 	if (ret) {
127 		pr_err("unable to find syscon device (%d)\n", ret);
128 		return ret;
129 	}
130 
131 	/* get syscfg-reg base address */
132 	regmap = syscon_get_regmap(syscon);
133 	if (!regmap) {
134 		pr_err("unable to find regmap\n");
135 		return -ENODEV;
136 	}
137 	plat->syscfg_base = regmap->base;
138 
139 	/* get powerdown reset */
140 	ret = reset_get_by_name(dev, "powerdown", &plat->powerdown_ctl);
141 	if (ret) {
142 		pr_err("can't get powerdown reset for %s (%d)", dev->name, ret);
143 		return ret;
144 	}
145 
146 	/* get softreset reset */
147 	ret = reset_get_by_name(dev, "softreset", &plat->softreset_ctl);
148 	if (ret)
149 		pr_err("can't get soft reset for %s (%d)", dev->name, ret);
150 
151 	return ret;
152 };
153 
154 static int sti_dwc3_glue_bind(struct udevice *dev)
155 {
156 	struct sti_dwc3_glue_platdata *plat = dev_get_platdata(dev);
157 	int dwc3_node;
158 
159 	/* check if one subnode is present */
160 	dwc3_node = fdt_first_subnode(gd->fdt_blob, dev_of_offset(dev));
161 	if (dwc3_node <= 0) {
162 		pr_err("Can't find subnode for %s\n", dev->name);
163 		return -ENODEV;
164 	}
165 
166 	/* check if the subnode compatible string is the dwc3 one*/
167 	if (fdt_node_check_compatible(gd->fdt_blob, dwc3_node,
168 				      "snps,dwc3") != 0) {
169 		pr_err("Can't find dwc3 subnode for %s\n", dev->name);
170 		return -ENODEV;
171 	}
172 
173 	/* retrieve the DWC3 dual role mode */
174 	plat->mode = usb_get_dr_mode(dwc3_node);
175 	if (plat->mode == USB_DR_MODE_UNKNOWN)
176 		/* by default set dual role mode to HOST */
177 		plat->mode = USB_DR_MODE_HOST;
178 
179 	return dm_scan_fdt_dev(dev);
180 }
181 
182 static int sti_dwc3_glue_probe(struct udevice *dev)
183 {
184 	struct sti_dwc3_glue_platdata *plat = dev_get_platdata(dev);
185 	int ret;
186 
187 	/* deassert both powerdown and softreset */
188 	ret = reset_deassert(&plat->powerdown_ctl);
189 	if (ret < 0) {
190 		pr_err("DWC3 powerdown reset deassert failed: %d", ret);
191 		return ret;
192 	}
193 
194 	ret = reset_deassert(&plat->softreset_ctl);
195 	if (ret < 0) {
196 		pr_err("DWC3 soft reset deassert failed: %d", ret);
197 		goto softreset_err;
198 	}
199 
200 	ret = sti_dwc3_glue_drd_init(plat);
201 	if (ret)
202 		goto init_err;
203 
204 	sti_dwc3_glue_init(plat);
205 
206 	return 0;
207 
208 init_err:
209 	ret = reset_assert(&plat->softreset_ctl);
210 	if (ret < 0) {
211 		pr_err("DWC3 soft reset deassert failed: %d", ret);
212 		return ret;
213 	}
214 
215 softreset_err:
216 	ret = reset_assert(&plat->powerdown_ctl);
217 	if (ret < 0)
218 		pr_err("DWC3 powerdown reset deassert failed: %d", ret);
219 
220 	return ret;
221 }
222 
223 static int sti_dwc3_glue_remove(struct udevice *dev)
224 {
225 	struct sti_dwc3_glue_platdata *plat = dev_get_platdata(dev);
226 	int ret;
227 
228 	/* assert both powerdown and softreset */
229 	ret = reset_assert(&plat->powerdown_ctl);
230 	if (ret < 0) {
231 		pr_err("DWC3 powerdown reset deassert failed: %d", ret);
232 		return ret;
233 	}
234 
235 	ret = reset_assert(&plat->softreset_ctl);
236 	if (ret < 0)
237 		pr_err("DWC3 soft reset deassert failed: %d", ret);
238 
239 	return ret;
240 }
241 
242 static const struct udevice_id sti_dwc3_glue_ids[] = {
243 	{ .compatible = "st,stih407-dwc3" },
244 	{ }
245 };
246 
247 U_BOOT_DRIVER(dwc3_sti_glue) = {
248 	.name = "dwc3_sti_glue",
249 	.id = UCLASS_MISC,
250 	.of_match = sti_dwc3_glue_ids,
251 	.ofdata_to_platdata = sti_dwc3_glue_ofdata_to_platdata,
252 	.probe = sti_dwc3_glue_probe,
253 	.remove = sti_dwc3_glue_remove,
254 	.bind = sti_dwc3_glue_bind,
255 	.platdata_auto_alloc_size = sizeof(struct sti_dwc3_glue_platdata),
256 	.flags = DM_FLAG_ALLOC_PRIV_DMA,
257 };
258