1637cee5fSGabriel Fernandez // SPDX-License-Identifier: GPL-2.0
2637cee5fSGabriel Fernandez /*
3637cee5fSGabriel Fernandez * Copyright (C) STMicroelectronics 2022 - All Rights Reserved
4637cee5fSGabriel Fernandez * Author: Gabriel Fernandez <gabriel.fernandez@foss.st.com> for STMicroelectronics.
5637cee5fSGabriel Fernandez */
6637cee5fSGabriel Fernandez
7637cee5fSGabriel Fernandez #include <linux/of.h>
8637cee5fSGabriel Fernandez #include <linux/platform_device.h>
9637cee5fSGabriel Fernandez #include <linux/regmap.h>
10637cee5fSGabriel Fernandez #include <linux/reset-controller.h>
11637cee5fSGabriel Fernandez #include <linux/slab.h>
12637cee5fSGabriel Fernandez #include <linux/spinlock.h>
13637cee5fSGabriel Fernandez
1430500c2aSGabriel Fernandez #include "reset-stm32.h"
15637cee5fSGabriel Fernandez
16637cee5fSGabriel Fernandez struct stm32_reset_data {
17637cee5fSGabriel Fernandez /* reset lock */
18637cee5fSGabriel Fernandez spinlock_t lock;
19637cee5fSGabriel Fernandez struct reset_controller_dev rcdev;
20637cee5fSGabriel Fernandez void __iomem *membase;
21637cee5fSGabriel Fernandez u32 clear_offset;
22*fd7a1c90SGabriel Fernandez const struct stm32_reset_cfg **reset_lines;
23637cee5fSGabriel Fernandez };
24637cee5fSGabriel Fernandez
25637cee5fSGabriel Fernandez static inline struct stm32_reset_data *
to_stm32_reset_data(struct reset_controller_dev * rcdev)26637cee5fSGabriel Fernandez to_stm32_reset_data(struct reset_controller_dev *rcdev)
27637cee5fSGabriel Fernandez {
28637cee5fSGabriel Fernandez return container_of(rcdev, struct stm32_reset_data, rcdev);
29637cee5fSGabriel Fernandez }
30637cee5fSGabriel Fernandez
stm32_get_reset_line(struct reset_controller_dev * rcdev,unsigned long id,struct stm32_reset_cfg * line)31*fd7a1c90SGabriel Fernandez static const struct stm32_reset_cfg *stm32_get_reset_line(struct reset_controller_dev *rcdev,
32*fd7a1c90SGabriel Fernandez unsigned long id,
33*fd7a1c90SGabriel Fernandez struct stm32_reset_cfg *line)
34637cee5fSGabriel Fernandez {
35637cee5fSGabriel Fernandez struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
36*fd7a1c90SGabriel Fernandez
37*fd7a1c90SGabriel Fernandez if (!data->reset_lines) {
38637cee5fSGabriel Fernandez int reg_width = sizeof(u32);
39637cee5fSGabriel Fernandez int bank = id / (reg_width * BITS_PER_BYTE);
40637cee5fSGabriel Fernandez int offset = id % (reg_width * BITS_PER_BYTE);
41637cee5fSGabriel Fernandez
42*fd7a1c90SGabriel Fernandez line->offset = bank * reg_width;
43*fd7a1c90SGabriel Fernandez line->bit_idx = offset;
44*fd7a1c90SGabriel Fernandez line->set_clr = (data->clear_offset ? true : false);
45*fd7a1c90SGabriel Fernandez
46*fd7a1c90SGabriel Fernandez return line;
47*fd7a1c90SGabriel Fernandez }
48*fd7a1c90SGabriel Fernandez
49*fd7a1c90SGabriel Fernandez return data->reset_lines[id];
50*fd7a1c90SGabriel Fernandez }
51*fd7a1c90SGabriel Fernandez
stm32_reset_update(struct reset_controller_dev * rcdev,unsigned long id,bool assert)52*fd7a1c90SGabriel Fernandez static int stm32_reset_update(struct reset_controller_dev *rcdev,
53*fd7a1c90SGabriel Fernandez unsigned long id, bool assert)
54*fd7a1c90SGabriel Fernandez {
55*fd7a1c90SGabriel Fernandez struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
56*fd7a1c90SGabriel Fernandez struct stm32_reset_cfg line_reset;
57*fd7a1c90SGabriel Fernandez const struct stm32_reset_cfg *ptr_line;
58*fd7a1c90SGabriel Fernandez
59*fd7a1c90SGabriel Fernandez ptr_line = stm32_get_reset_line(rcdev, id, &line_reset);
60*fd7a1c90SGabriel Fernandez if (!ptr_line)
61*fd7a1c90SGabriel Fernandez return -EPERM;
62*fd7a1c90SGabriel Fernandez
63*fd7a1c90SGabriel Fernandez if (ptr_line->set_clr) {
64637cee5fSGabriel Fernandez void __iomem *addr;
65637cee5fSGabriel Fernandez
66*fd7a1c90SGabriel Fernandez addr = data->membase + ptr_line->offset;
67637cee5fSGabriel Fernandez if (!assert)
68637cee5fSGabriel Fernandez addr += data->clear_offset;
69637cee5fSGabriel Fernandez
70*fd7a1c90SGabriel Fernandez writel(BIT(ptr_line->bit_idx), addr);
71637cee5fSGabriel Fernandez
72637cee5fSGabriel Fernandez } else {
73637cee5fSGabriel Fernandez unsigned long flags;
74637cee5fSGabriel Fernandez u32 reg;
75637cee5fSGabriel Fernandez
76637cee5fSGabriel Fernandez spin_lock_irqsave(&data->lock, flags);
77637cee5fSGabriel Fernandez
78*fd7a1c90SGabriel Fernandez reg = readl(data->membase + ptr_line->offset);
79637cee5fSGabriel Fernandez
80637cee5fSGabriel Fernandez if (assert)
81*fd7a1c90SGabriel Fernandez reg |= BIT(ptr_line->bit_idx);
82637cee5fSGabriel Fernandez else
83*fd7a1c90SGabriel Fernandez reg &= ~BIT(ptr_line->bit_idx);
84637cee5fSGabriel Fernandez
85*fd7a1c90SGabriel Fernandez writel(reg, data->membase + ptr_line->offset);
86637cee5fSGabriel Fernandez
87637cee5fSGabriel Fernandez spin_unlock_irqrestore(&data->lock, flags);
88637cee5fSGabriel Fernandez }
89637cee5fSGabriel Fernandez
90637cee5fSGabriel Fernandez return 0;
91637cee5fSGabriel Fernandez }
92637cee5fSGabriel Fernandez
stm32_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)93637cee5fSGabriel Fernandez static int stm32_reset_assert(struct reset_controller_dev *rcdev,
94637cee5fSGabriel Fernandez unsigned long id)
95637cee5fSGabriel Fernandez {
96637cee5fSGabriel Fernandez return stm32_reset_update(rcdev, id, true);
97637cee5fSGabriel Fernandez }
98637cee5fSGabriel Fernandez
stm32_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)99637cee5fSGabriel Fernandez static int stm32_reset_deassert(struct reset_controller_dev *rcdev,
100637cee5fSGabriel Fernandez unsigned long id)
101637cee5fSGabriel Fernandez {
102637cee5fSGabriel Fernandez return stm32_reset_update(rcdev, id, false);
103637cee5fSGabriel Fernandez }
104637cee5fSGabriel Fernandez
stm32_reset_status(struct reset_controller_dev * rcdev,unsigned long id)105637cee5fSGabriel Fernandez static int stm32_reset_status(struct reset_controller_dev *rcdev,
106637cee5fSGabriel Fernandez unsigned long id)
107637cee5fSGabriel Fernandez {
108637cee5fSGabriel Fernandez struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
109*fd7a1c90SGabriel Fernandez struct stm32_reset_cfg line_reset;
110*fd7a1c90SGabriel Fernandez const struct stm32_reset_cfg *ptr_line;
111637cee5fSGabriel Fernandez u32 reg;
112637cee5fSGabriel Fernandez
113*fd7a1c90SGabriel Fernandez ptr_line = stm32_get_reset_line(rcdev, id, &line_reset);
114*fd7a1c90SGabriel Fernandez if (!ptr_line)
115*fd7a1c90SGabriel Fernandez return -EPERM;
116637cee5fSGabriel Fernandez
117*fd7a1c90SGabriel Fernandez reg = readl(data->membase + ptr_line->offset);
118*fd7a1c90SGabriel Fernandez
119*fd7a1c90SGabriel Fernandez return !!(reg & BIT(ptr_line->bit_idx));
120637cee5fSGabriel Fernandez }
121637cee5fSGabriel Fernandez
122637cee5fSGabriel Fernandez static const struct reset_control_ops stm32_reset_ops = {
123637cee5fSGabriel Fernandez .assert = stm32_reset_assert,
124637cee5fSGabriel Fernandez .deassert = stm32_reset_deassert,
125637cee5fSGabriel Fernandez .status = stm32_reset_status,
126637cee5fSGabriel Fernandez };
127637cee5fSGabriel Fernandez
stm32_rcc_reset_init(struct device * dev,struct clk_stm32_reset_data * data,void __iomem * base)12830500c2aSGabriel Fernandez int stm32_rcc_reset_init(struct device *dev, struct clk_stm32_reset_data *data,
129637cee5fSGabriel Fernandez void __iomem *base)
130637cee5fSGabriel Fernandez {
13130500c2aSGabriel Fernandez struct stm32_reset_data *reset_data;
132637cee5fSGabriel Fernandez
133637cee5fSGabriel Fernandez reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
134637cee5fSGabriel Fernandez if (!reset_data)
135637cee5fSGabriel Fernandez return -ENOMEM;
136637cee5fSGabriel Fernandez
137a1ea0857SWei Yongjun spin_lock_init(&reset_data->lock);
13830500c2aSGabriel Fernandez
139637cee5fSGabriel Fernandez reset_data->membase = base;
140637cee5fSGabriel Fernandez reset_data->rcdev.owner = THIS_MODULE;
141637cee5fSGabriel Fernandez reset_data->rcdev.ops = &stm32_reset_ops;
142637cee5fSGabriel Fernandez reset_data->rcdev.of_node = dev_of_node(dev);
14330500c2aSGabriel Fernandez reset_data->rcdev.nr_resets = data->nr_lines;
144*fd7a1c90SGabriel Fernandez reset_data->reset_lines = data->reset_lines;
145637cee5fSGabriel Fernandez reset_data->clear_offset = data->clear_offset;
146637cee5fSGabriel Fernandez
147637cee5fSGabriel Fernandez return reset_controller_register(&reset_data->rcdev);
148637cee5fSGabriel Fernandez }
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