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 *
to_zynqmp_reset_data(struct reset_controller_dev * rcdev)29 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
30 {
31 	return container_of(rcdev, struct zynqmp_reset_data, rcdev);
32 }
33 
zynqmp_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)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 
zynqmp_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)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 
zynqmp_reset_status(struct reset_controller_dev * rcdev,unsigned long id)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 err;
57 	u32 val;
58 
59 	err = zynqmp_pm_reset_get_status(priv->data->reset_id + id, &val);
60 	if (err)
61 		return err;
62 
63 	return val;
64 }
65 
zynqmp_reset_reset(struct reset_controller_dev * rcdev,unsigned long id)66 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
67 			      unsigned long id)
68 {
69 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
70 
71 	return zynqmp_pm_reset_assert(priv->data->reset_id + id,
72 				      PM_RESET_ACTION_PULSE);
73 }
74 
zynqmp_reset_of_xlate(struct reset_controller_dev * rcdev,const struct of_phandle_args * reset_spec)75 static int zynqmp_reset_of_xlate(struct reset_controller_dev *rcdev,
76 				 const struct of_phandle_args *reset_spec)
77 {
78 	return reset_spec->args[0];
79 }
80 
81 static const struct zynqmp_reset_soc_data zynqmp_reset_data = {
82 	.reset_id = ZYNQMP_RESET_ID,
83 	.num_resets = ZYNQMP_NR_RESETS,
84 };
85 
86 static const struct zynqmp_reset_soc_data versal_reset_data = {
87 	.reset_id = 0,
88 	.num_resets = VERSAL_NR_RESETS,
89 };
90 
91 static const struct reset_control_ops zynqmp_reset_ops = {
92 	.reset = zynqmp_reset_reset,
93 	.assert = zynqmp_reset_assert,
94 	.deassert = zynqmp_reset_deassert,
95 	.status = zynqmp_reset_status,
96 };
97 
zynqmp_reset_probe(struct platform_device * pdev)98 static int zynqmp_reset_probe(struct platform_device *pdev)
99 {
100 	struct zynqmp_reset_data *priv;
101 
102 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
103 	if (!priv)
104 		return -ENOMEM;
105 
106 	priv->data = of_device_get_match_data(&pdev->dev);
107 	if (!priv->data)
108 		return -EINVAL;
109 
110 	platform_set_drvdata(pdev, priv);
111 
112 	priv->rcdev.ops = &zynqmp_reset_ops;
113 	priv->rcdev.owner = THIS_MODULE;
114 	priv->rcdev.of_node = pdev->dev.of_node;
115 	priv->rcdev.nr_resets = priv->data->num_resets;
116 	priv->rcdev.of_reset_n_cells = 1;
117 	priv->rcdev.of_xlate = zynqmp_reset_of_xlate;
118 
119 	return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
120 }
121 
122 static const struct of_device_id zynqmp_reset_dt_ids[] = {
123 	{ .compatible = "xlnx,zynqmp-reset", .data = &zynqmp_reset_data, },
124 	{ .compatible = "xlnx,versal-reset", .data = &versal_reset_data, },
125 	{ /* sentinel */ },
126 };
127 
128 static struct platform_driver zynqmp_reset_driver = {
129 	.probe	= zynqmp_reset_probe,
130 	.driver = {
131 		.name		= KBUILD_MODNAME,
132 		.of_match_table	= zynqmp_reset_dt_ids,
133 	},
134 };
135 
zynqmp_reset_init(void)136 static int __init zynqmp_reset_init(void)
137 {
138 	return platform_driver_register(&zynqmp_reset_driver);
139 }
140 
141 arch_initcall(zynqmp_reset_init);
142