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