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
33enum hi6220_reset_ctrl_type {
34	PERIPHERAL,
35	MEDIA,
36	AO,
37};
38
39struct hi6220_reset_data {
40	struct reset_controller_dev rc_dev;
41	struct regmap *regmap;
42};
43
44static 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
56static 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
68static const struct reset_control_ops hi6220_peripheral_reset_ops = {
69	.assert = hi6220_peripheral_assert,
70	.deassert = hi6220_peripheral_deassert,
71};
72
73static 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
82static 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
91static 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
106static 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
125static 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
150static const struct reset_control_ops hi6220_ao_reset_ops = {
151	.assert = hi6220_ao_assert,
152	.deassert = hi6220_ao_deassert,
153};
154
155static 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
191static 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};
206MODULE_DEVICE_TABLE(of, hi6220_reset_match);
207
208static 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
216static int __init hi6220_reset_init(void)
217{
218	return platform_driver_register(&hi6220_reset_driver);
219}
220
221postcore_initcall(hi6220_reset_init);
222
223MODULE_LICENSE("GPL v2");
224