xref: /linux/drivers/reset/reset-zynqmp.c (revision 6c363eafc4d637ac4bd83d4a7dd06dd3cfbe7c5f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018 Xilinx, Inc.
4  *
5  */
6 
7 #include <linux/err.h>
8 #include <linux/of.h>
9 #include <linux/platform_device.h>
10 #include <linux/reset-controller.h>
11 #include <linux/firmware/xlnx-zynqmp.h>
12 #include <linux/of_device.h>
13 
14 #define ZYNQMP_NR_RESETS (ZYNQMP_PM_RESET_END - ZYNQMP_PM_RESET_START)
15 #define ZYNQMP_RESET_ID ZYNQMP_PM_RESET_START
16 #define VERSAL_NR_RESETS	95
17 
18 struct zynqmp_reset_soc_data {
19 	u32 reset_id;
20 	u32 num_resets;
21 };
22 
23 struct zynqmp_reset_data {
24 	struct reset_controller_dev rcdev;
25 	const struct zynqmp_reset_soc_data *data;
26 };
27 
28 static inline struct zynqmp_reset_data *
29 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
30 {
31 	return container_of(rcdev, struct zynqmp_reset_data, rcdev);
32 }
33 
34 static int zynqmp_reset_assert(struct reset_controller_dev *rcdev,
35 			       unsigned long id)
36 {
37 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
38 
39 	return zynqmp_pm_reset_assert(priv->data->reset_id + id,
40 				      PM_RESET_ACTION_ASSERT);
41 }
42 
43 static int zynqmp_reset_deassert(struct reset_controller_dev *rcdev,
44 				 unsigned long id)
45 {
46 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
47 
48 	return zynqmp_pm_reset_assert(priv->data->reset_id + id,
49 				      PM_RESET_ACTION_RELEASE);
50 }
51 
52 static int zynqmp_reset_status(struct reset_controller_dev *rcdev,
53 			       unsigned long id)
54 {
55 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
56 	int val, err;
57 
58 	err = zynqmp_pm_reset_get_status(priv->data->reset_id + id, &val);
59 	if (err)
60 		return err;
61 
62 	return val;
63 }
64 
65 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
66 			      unsigned long id)
67 {
68 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
69 
70 	return zynqmp_pm_reset_assert(priv->data->reset_id + id,
71 				      PM_RESET_ACTION_PULSE);
72 }
73 
74 static int zynqmp_reset_of_xlate(struct reset_controller_dev *rcdev,
75 				 const struct of_phandle_args *reset_spec)
76 {
77 	return reset_spec->args[0];
78 }
79 
80 static const struct zynqmp_reset_soc_data zynqmp_reset_data = {
81 	.reset_id = ZYNQMP_RESET_ID,
82 	.num_resets = ZYNQMP_NR_RESETS,
83 };
84 
85 static const struct zynqmp_reset_soc_data versal_reset_data = {
86         .reset_id = 0,
87         .num_resets = VERSAL_NR_RESETS,
88 };
89 
90 static const struct reset_control_ops zynqmp_reset_ops = {
91 	.reset = zynqmp_reset_reset,
92 	.assert = zynqmp_reset_assert,
93 	.deassert = zynqmp_reset_deassert,
94 	.status = zynqmp_reset_status,
95 };
96 
97 static int zynqmp_reset_probe(struct platform_device *pdev)
98 {
99 	struct zynqmp_reset_data *priv;
100 
101 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
102 	if (!priv)
103 		return -ENOMEM;
104 
105 	priv->data = of_device_get_match_data(&pdev->dev);
106 	if (!priv->data)
107 		return -EINVAL;
108 
109 	platform_set_drvdata(pdev, priv);
110 
111 	priv->rcdev.ops = &zynqmp_reset_ops;
112 	priv->rcdev.owner = THIS_MODULE;
113 	priv->rcdev.of_node = pdev->dev.of_node;
114 	priv->rcdev.nr_resets = priv->data->num_resets;
115 	priv->rcdev.of_reset_n_cells = 1;
116 	priv->rcdev.of_xlate = zynqmp_reset_of_xlate;
117 
118 	return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
119 }
120 
121 static const struct of_device_id zynqmp_reset_dt_ids[] = {
122 	{ .compatible = "xlnx,zynqmp-reset", .data = &zynqmp_reset_data, },
123 	{ .compatible = "xlnx,versal-reset", .data = &versal_reset_data, },
124 	{ /* sentinel */ },
125 };
126 
127 static struct platform_driver zynqmp_reset_driver = {
128 	.probe	= zynqmp_reset_probe,
129 	.driver = {
130 		.name		= KBUILD_MODNAME,
131 		.of_match_table	= zynqmp_reset_dt_ids,
132 	},
133 };
134 
135 static int __init zynqmp_reset_init(void)
136 {
137 	return platform_driver_register(&zynqmp_reset_driver);
138 }
139 
140 arch_initcall(zynqmp_reset_init);
141