1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Hisilicon Hi6220 reset controller driver
4 *
5 * Copyright (c) 2016 Linaro Limited.
6 * Copyright (c) 2015-2016 Hisilicon Limited.
7 *
8 * Author: Feng Chen <puck.chen@hisilicon.com>
9 */
10
11 #include <linux/io.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/bitops.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17 #include <linux/regmap.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/reset-controller.h>
20 #include <linux/reset.h>
21 #include <linux/platform_device.h>
22
23 #define PERIPH_ASSERT_OFFSET 0x300
24 #define PERIPH_DEASSERT_OFFSET 0x304
25 #define PERIPH_MAX_INDEX 0x509
26
27 #define SC_MEDIA_RSTEN 0x052C
28 #define SC_MEDIA_RSTDIS 0x0530
29 #define MEDIA_MAX_INDEX 8
30
31 #define to_reset_data(x) container_of(x, struct hi6220_reset_data, rc_dev)
32
33 enum hi6220_reset_ctrl_type {
34 PERIPHERAL,
35 MEDIA,
36 AO,
37 };
38
39 struct hi6220_reset_data {
40 struct reset_controller_dev rc_dev;
41 struct regmap *regmap;
42 };
43
hi6220_peripheral_assert(struct reset_controller_dev * rc_dev,unsigned long idx)44 static int hi6220_peripheral_assert(struct reset_controller_dev *rc_dev,
45 unsigned long idx)
46 {
47 struct hi6220_reset_data *data = to_reset_data(rc_dev);
48 struct regmap *regmap = data->regmap;
49 u32 bank = idx >> 8;
50 u32 offset = idx & 0xff;
51 u32 reg = PERIPH_ASSERT_OFFSET + bank * 0x10;
52
53 return regmap_write(regmap, reg, BIT(offset));
54 }
55
hi6220_peripheral_deassert(struct reset_controller_dev * rc_dev,unsigned long idx)56 static int hi6220_peripheral_deassert(struct reset_controller_dev *rc_dev,
57 unsigned long idx)
58 {
59 struct hi6220_reset_data *data = to_reset_data(rc_dev);
60 struct regmap *regmap = data->regmap;
61 u32 bank = idx >> 8;
62 u32 offset = idx & 0xff;
63 u32 reg = PERIPH_DEASSERT_OFFSET + bank * 0x10;
64
65 return regmap_write(regmap, reg, BIT(offset));
66 }
67
68 static const struct reset_control_ops hi6220_peripheral_reset_ops = {
69 .assert = hi6220_peripheral_assert,
70 .deassert = hi6220_peripheral_deassert,
71 };
72
hi6220_media_assert(struct reset_controller_dev * rc_dev,unsigned long idx)73 static int hi6220_media_assert(struct reset_controller_dev *rc_dev,
74 unsigned long idx)
75 {
76 struct hi6220_reset_data *data = to_reset_data(rc_dev);
77 struct regmap *regmap = data->regmap;
78
79 return regmap_write(regmap, SC_MEDIA_RSTEN, BIT(idx));
80 }
81
hi6220_media_deassert(struct reset_controller_dev * rc_dev,unsigned long idx)82 static int hi6220_media_deassert(struct reset_controller_dev *rc_dev,
83 unsigned long idx)
84 {
85 struct hi6220_reset_data *data = to_reset_data(rc_dev);
86 struct regmap *regmap = data->regmap;
87
88 return regmap_write(regmap, SC_MEDIA_RSTDIS, BIT(idx));
89 }
90
91 static const struct reset_control_ops hi6220_media_reset_ops = {
92 .assert = hi6220_media_assert,
93 .deassert = hi6220_media_deassert,
94 };
95
96 #define AO_SCTRL_SC_PW_CLKEN0 0x800
97 #define AO_SCTRL_SC_PW_CLKDIS0 0x804
98
99 #define AO_SCTRL_SC_PW_RSTEN0 0x810
100 #define AO_SCTRL_SC_PW_RSTDIS0 0x814
101
102 #define AO_SCTRL_SC_PW_ISOEN0 0x820
103 #define AO_SCTRL_SC_PW_ISODIS0 0x824
104 #define AO_MAX_INDEX 12
105
hi6220_ao_assert(struct reset_controller_dev * rc_dev,unsigned long idx)106 static int hi6220_ao_assert(struct reset_controller_dev *rc_dev,
107 unsigned long idx)
108 {
109 struct hi6220_reset_data *data = to_reset_data(rc_dev);
110 struct regmap *regmap = data->regmap;
111 int ret;
112
113 ret = regmap_write(regmap, AO_SCTRL_SC_PW_RSTEN0, BIT(idx));
114 if (ret)
115 return ret;
116
117 ret = regmap_write(regmap, AO_SCTRL_SC_PW_ISOEN0, BIT(idx));
118 if (ret)
119 return ret;
120
121 ret = regmap_write(regmap, AO_SCTRL_SC_PW_CLKDIS0, BIT(idx));
122 return ret;
123 }
124
hi6220_ao_deassert(struct reset_controller_dev * rc_dev,unsigned long idx)125 static int hi6220_ao_deassert(struct reset_controller_dev *rc_dev,
126 unsigned long idx)
127 {
128 struct hi6220_reset_data *data = to_reset_data(rc_dev);
129 struct regmap *regmap = data->regmap;
130 int ret;
131
132 /*
133 * It was suggested to disable isolation before enabling
134 * the clocks and deasserting reset, to avoid glitches.
135 * But this order is preserved to keep it matching the
136 * vendor code.
137 */
138 ret = regmap_write(regmap, AO_SCTRL_SC_PW_RSTDIS0, BIT(idx));
139 if (ret)
140 return ret;
141
142 ret = regmap_write(regmap, AO_SCTRL_SC_PW_ISODIS0, BIT(idx));
143 if (ret)
144 return ret;
145
146 ret = regmap_write(regmap, AO_SCTRL_SC_PW_CLKEN0, BIT(idx));
147 return ret;
148 }
149
150 static const struct reset_control_ops hi6220_ao_reset_ops = {
151 .assert = hi6220_ao_assert,
152 .deassert = hi6220_ao_deassert,
153 };
154
hi6220_reset_probe(struct platform_device * pdev)155 static int hi6220_reset_probe(struct platform_device *pdev)
156 {
157 struct device_node *np = pdev->dev.of_node;
158 struct device *dev = &pdev->dev;
159 enum hi6220_reset_ctrl_type type;
160 struct hi6220_reset_data *data;
161 struct regmap *regmap;
162
163 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
164 if (!data)
165 return -ENOMEM;
166
167 type = (uintptr_t)of_device_get_match_data(dev);
168
169 regmap = syscon_node_to_regmap(np);
170 if (IS_ERR(regmap)) {
171 dev_err(dev, "failed to get reset controller regmap\n");
172 return PTR_ERR(regmap);
173 }
174
175 data->regmap = regmap;
176 data->rc_dev.of_node = np;
177 if (type == MEDIA) {
178 data->rc_dev.ops = &hi6220_media_reset_ops;
179 data->rc_dev.nr_resets = MEDIA_MAX_INDEX;
180 } else if (type == PERIPHERAL) {
181 data->rc_dev.ops = &hi6220_peripheral_reset_ops;
182 data->rc_dev.nr_resets = PERIPH_MAX_INDEX;
183 } else {
184 data->rc_dev.ops = &hi6220_ao_reset_ops;
185 data->rc_dev.nr_resets = AO_MAX_INDEX;
186 }
187
188 return reset_controller_register(&data->rc_dev);
189 }
190
191 static const struct of_device_id hi6220_reset_match[] = {
192 {
193 .compatible = "hisilicon,hi6220-sysctrl",
194 .data = (void *)PERIPHERAL,
195 },
196 {
197 .compatible = "hisilicon,hi6220-mediactrl",
198 .data = (void *)MEDIA,
199 },
200 {
201 .compatible = "hisilicon,hi6220-aoctrl",
202 .data = (void *)AO,
203 },
204 { /* sentinel */ },
205 };
206 MODULE_DEVICE_TABLE(of, hi6220_reset_match);
207
208 static struct platform_driver hi6220_reset_driver = {
209 .probe = hi6220_reset_probe,
210 .driver = {
211 .name = "reset-hi6220",
212 .of_match_table = hi6220_reset_match,
213 },
214 };
215
hi6220_reset_init(void)216 static int __init hi6220_reset_init(void)
217 {
218 return platform_driver_register(&hi6220_reset_driver);
219 }
220
221 postcore_initcall(hi6220_reset_init);
222
223 MODULE_LICENSE("GPL v2");
224