[linux-2.6-block.git] / drivers / reset / reset-sunplus.c

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/*
 * SP7021 reset driver
 *
 * Copyright (C) Sunplus Technology Co., Ltd.
 *       All rights reserved.
 */

#include <linux/io.h>
#include <linux/init.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/reboot.h>

/* HIWORD_MASK_REG BITS */
#define BITS_PER_HWM_REG	16

/* resets HW info: reg_index_shift */
static const u32 sp_resets[] = {
/* SP7021: mo_reset0 ~ mo_reset9 */
	0x00,
	0x02,
	0x03,
	0x04,
	0x05,
	0x06,
	0x07,
	0x08,
	0x09,
	0x0a,
	0x0b,
	0x0d,
	0x0e,
	0x0f,
	0x10,
	0x12,
	0x14,
	0x15,
	0x16,
	0x17,
	0x18,
	0x19,
	0x1a,
	0x1b,
	0x1c,
	0x1d,
	0x1e,
	0x1f,
	0x20,
	0x21,
	0x22,
	0x23,
	0x24,
	0x25,
	0x26,
	0x2a,
	0x2b,
	0x2d,
	0x2e,
	0x30,
	0x31,
	0x32,
	0x33,
	0x3d,
	0x3e,
	0x3f,
	0x42,
	0x44,
	0x4b,
	0x4c,
	0x4d,
	0x4e,
	0x4f,
	0x50,
	0x55,
	0x60,
	0x61,
	0x6a,
	0x6f,
	0x70,
	0x73,
	0x74,
	0x86,
	0x8a,
	0x8b,
	0x8d,
	0x8e,
	0x8f,
	0x90,
	0x92,
	0x93,
	0x94,
	0x95,
	0x96,
	0x97,
	0x98,
	0x99,
};

struct sp_reset {
	struct reset_controller_dev rcdev;
	struct notifier_block notifier;
	void __iomem *base;
};

static inline struct sp_reset *to_sp_reset(struct reset_controller_dev *rcdev)
{
	return container_of(rcdev, struct sp_reset, rcdev);
}

static int sp_reset_update(struct reset_controller_dev *rcdev,
			   unsigned long id, bool assert)
{
	struct sp_reset *reset = to_sp_reset(rcdev);
	int index = sp_resets[id] / BITS_PER_HWM_REG;
	int shift = sp_resets[id] % BITS_PER_HWM_REG;
	u32 val;

	val = (1 << (16 + shift)) | (assert << shift);
	writel(val, reset->base + (index * 4));

	return 0;
}

static int sp_reset_assert(struct reset_controller_dev *rcdev,
			   unsigned long id)
{
	return sp_reset_update(rcdev, id, true);
}

static int sp_reset_deassert(struct reset_controller_dev *rcdev,
			     unsigned long id)
{
	return sp_reset_update(rcdev, id, false);
}

static int sp_reset_status(struct reset_controller_dev *rcdev,
			   unsigned long id)
{
	struct sp_reset *reset = to_sp_reset(rcdev);
	int index = sp_resets[id] / BITS_PER_HWM_REG;
	int shift = sp_resets[id] % BITS_PER_HWM_REG;
	u32 reg;

	reg = readl(reset->base + (index * 4));

	return !!(reg & BIT(shift));
}

static const struct reset_control_ops sp_reset_ops = {
	.assert   = sp_reset_assert,
	.deassert = sp_reset_deassert,
	.status   = sp_reset_status,
};

static int sp_restart(struct notifier_block *nb, unsigned long mode,
		      void *cmd)
{
	struct sp_reset *reset = container_of(nb, struct sp_reset, notifier);

	sp_reset_assert(&reset->rcdev, 0);
	sp_reset_deassert(&reset->rcdev, 0);

	return NOTIFY_DONE;
}

static int sp_reset_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct sp_reset *reset;
	struct resource *res;
	int ret;

	reset = devm_kzalloc(dev, sizeof(*reset), GFP_KERNEL);
	if (!reset)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	reset->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(reset->base))
		return PTR_ERR(reset->base);

	reset->rcdev.ops = &sp_reset_ops;
	reset->rcdev.owner = THIS_MODULE;
	reset->rcdev.of_node = dev->of_node;
	reset->rcdev.nr_resets = resource_size(res) / 4 * BITS_PER_HWM_REG;

	ret = devm_reset_controller_register(dev, &reset->rcdev);
	if (ret)
		return ret;

	reset->notifier.notifier_call = sp_restart;
	reset->notifier.priority = 192;

	return register_restart_handler(&reset->notifier);
}

static const struct of_device_id sp_reset_dt_ids[] = {
	{.compatible = "sunplus,sp7021-reset",},
	{ /* sentinel */ },
};

static struct platform_driver sp_reset_driver = {
	.probe = sp_reset_probe,
	.driver = {
		.name			= "sunplus-reset",
		.of_match_table		= sp_reset_dt_ids,
		.suppress_bind_attrs	= true,
	},
};
builtin_platform_driver(sp_reset_driver);
Commit	Line	Data
dbf018be QJ	1	// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
	2	/*
	3	* SP7021 reset driver
	4	*
	5	* Copyright (C) Sunplus Technology Co., Ltd.
	6	* All rights reserved.
	7	*/
	8
	9	#include <linux/io.h>
	10	#include <linux/init.h>
	11	#include <linux/mod_devicetable.h>
	12	#include <linux/platform_device.h>
	13	#include <linux/reset-controller.h>
	14	#include <linux/reboot.h>
	15
	16	/* HIWORD_MASK_REG BITS */
	17	#define BITS_PER_HWM_REG 16
	18
	19	/* resets HW info: reg_index_shift */
	20	static const u32 sp_resets[] = {
	21	/* SP7021: mo_reset0 ~ mo_reset9 */
	22	0x00,
	23	0x02,
	24	0x03,
	25	0x04,
	26	0x05,
	27	0x06,
	28	0x07,
	29	0x08,
	30	0x09,
	31	0x0a,
	32	0x0b,
	33	0x0d,
	34	0x0e,
	35	0x0f,
	36	0x10,
	37	0x12,
	38	0x14,
	39	0x15,
	40	0x16,
	41	0x17,
	42	0x18,
	43	0x19,
	44	0x1a,
	45	0x1b,
	46	0x1c,
	47	0x1d,
	48	0x1e,
	49	0x1f,
	50	0x20,
	51	0x21,
	52	0x22,
	53	0x23,
	54	0x24,
	55	0x25,
	56	0x26,
	57	0x2a,
	58	0x2b,
	59	0x2d,
	60	0x2e,
	61	0x30,
	62	0x31,
	63	0x32,
	64	0x33,
65	0x3d,
66	0x3e,
67	0x3f,
68	0x42,
69	0x44,
70	0x4b,
71	0x4c,
72	0x4d,
73	0x4e,
74	0x4f,
75	0x50,
76	0x55,
77	0x60,
78	0x61,
79	0x6a,
80	0x6f,
81	0x70,
82	0x73,
83	0x74,
84	0x86,
85	0x8a,
86	0x8b,
87	0x8d,
88	0x8e,
89	0x8f,
90	0x90,
91	0x92,
92	0x93,
93	0x94,
94	0x95,
95	0x96,
96	0x97,
97	0x98,
98	0x99,
99	};
100
101	struct sp_reset {
102	struct reset_controller_dev rcdev;
103	struct notifier_block notifier;
104	void __iomem *base;
105	};
106
107	static inline struct sp_reset to_sp_reset(struct reset_controller_dev rcdev)
108	{
109	return container_of(rcdev, struct sp_reset, rcdev);
110	}
111
112	static int sp_reset_update(struct reset_controller_dev *rcdev,
113	unsigned long id, bool assert)
114	{
115	struct sp_reset *reset = to_sp_reset(rcdev);
116	int index = sp_resets[id] / BITS_PER_HWM_REG;
117	int shift = sp_resets[id] % BITS_PER_HWM_REG;
118	u32 val;
119
120	val = (1 << (16 + shift)) \| (assert << shift);
121	writel(val, reset->base + (index * 4));
122
123	return 0;
124	}
125
126	static int sp_reset_assert(struct reset_controller_dev *rcdev,
127	unsigned long id)
128	{
129	return sp_reset_update(rcdev, id, true);
130	}
131
132	static int sp_reset_deassert(struct reset_controller_dev *rcdev,
133	unsigned long id)
134	{
135	return sp_reset_update(rcdev, id, false);
136	}
137
138	static int sp_reset_status(struct reset_controller_dev *rcdev,
139	unsigned long id)
140	{
141	struct sp_reset *reset = to_sp_reset(rcdev);
142	int index = sp_resets[id] / BITS_PER_HWM_REG;
143	int shift = sp_resets[id] % BITS_PER_HWM_REG;
144	u32 reg;
145
146	reg = readl(reset->base + (index * 4));
147
148	return !!(reg & BIT(shift));
149	}
150
151	static const struct reset_control_ops sp_reset_ops = {
152	.assert = sp_reset_assert,
153	.deassert = sp_reset_deassert,
154	.status = sp_reset_status,
155	};
156
157	static int sp_restart(struct notifier_block *nb, unsigned long mode,
158	void *cmd)
159	{
160	struct sp_reset *reset = container_of(nb, struct sp_reset, notifier);
161
162	sp_reset_assert(&reset->rcdev, 0);
163	sp_reset_deassert(&reset->rcdev, 0);
164
165	return NOTIFY_DONE;
166	}
167
168	static int sp_reset_probe(struct platform_device *pdev)
169	{
170	struct device *dev = &pdev->dev;
171	struct sp_reset *reset;
172	struct resource *res;
173	int ret;
174
175	reset = devm_kzalloc(dev, sizeof(*reset), GFP_KERNEL);
176	if (!reset)
177	return -ENOMEM;
178
179	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
180	reset->base = devm_ioremap_resource(dev, res);
181	if (IS_ERR(reset->base))
182	return PTR_ERR(reset->base);
183
184	reset->rcdev.ops = &sp_reset_ops;
185	reset->rcdev.owner = THIS_MODULE;
186	reset->rcdev.of_node = dev->of_node;
187	reset->rcdev.nr_resets = resource_size(res) / 4 * BITS_PER_HWM_REG;
188
189	ret = devm_reset_controller_register(dev, &reset->rcdev);
190	if (ret)
191	return ret;
192
193	reset->notifier.notifier_call = sp_restart;
194	reset->notifier.priority = 192;
195
196	return register_restart_handler(&reset->notifier);
197	}
198
199	static const struct of_device_id sp_reset_dt_ids[] = {
200	{.compatible = "sunplus,sp7021-reset",},
201	{ /* sentinel */ },
202	};
203
204	static struct platform_driver sp_reset_driver = {
205	.probe = sp_reset_probe,
206	.driver = {
207	.name = "sunplus-reset",
208	.of_match_table = sp_reset_dt_ids,
209	.suppress_bind_attrs = true,
210	},
211	};
212	builtin_platform_driver(sp_reset_driver);