xref: /openbmc/linux/drivers/reset/reset-zynqmp.c (revision 89e33ea7)
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 
13 #define ZYNQMP_NR_RESETS (ZYNQMP_PM_RESET_END - ZYNQMP_PM_RESET_START)
14 #define ZYNQMP_RESET_ID ZYNQMP_PM_RESET_START
15 
16 struct zynqmp_reset_data {
17 	struct reset_controller_dev rcdev;
18 	const struct zynqmp_eemi_ops *eemi_ops;
19 };
20 
21 static inline struct zynqmp_reset_data *
22 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
23 {
24 	return container_of(rcdev, struct zynqmp_reset_data, rcdev);
25 }
26 
27 static int zynqmp_reset_assert(struct reset_controller_dev *rcdev,
28 			       unsigned long id)
29 {
30 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
31 
32 	return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
33 					    PM_RESET_ACTION_ASSERT);
34 }
35 
36 static int zynqmp_reset_deassert(struct reset_controller_dev *rcdev,
37 				 unsigned long id)
38 {
39 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
40 
41 	return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
42 					    PM_RESET_ACTION_RELEASE);
43 }
44 
45 static int zynqmp_reset_status(struct reset_controller_dev *rcdev,
46 			       unsigned long id)
47 {
48 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
49 	int val, err;
50 
51 	err = priv->eemi_ops->reset_get_status(ZYNQMP_RESET_ID + id, &val);
52 	if (err)
53 		return err;
54 
55 	return val;
56 }
57 
58 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
59 			      unsigned long id)
60 {
61 	struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
62 
63 	return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
64 					    PM_RESET_ACTION_PULSE);
65 }
66 
67 static struct reset_control_ops zynqmp_reset_ops = {
68 	.reset = zynqmp_reset_reset,
69 	.assert = zynqmp_reset_assert,
70 	.deassert = zynqmp_reset_deassert,
71 	.status = zynqmp_reset_status,
72 };
73 
74 static int zynqmp_reset_probe(struct platform_device *pdev)
75 {
76 	struct zynqmp_reset_data *priv;
77 
78 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
79 	if (!priv)
80 		return -ENOMEM;
81 
82 	platform_set_drvdata(pdev, priv);
83 
84 	priv->eemi_ops = zynqmp_pm_get_eemi_ops();
85 	if (!priv->eemi_ops)
86 		return -ENXIO;
87 
88 	priv->rcdev.ops = &zynqmp_reset_ops;
89 	priv->rcdev.owner = THIS_MODULE;
90 	priv->rcdev.of_node = pdev->dev.of_node;
91 	priv->rcdev.nr_resets = ZYNQMP_NR_RESETS;
92 
93 	return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
94 }
95 
96 static const struct of_device_id zynqmp_reset_dt_ids[] = {
97 	{ .compatible = "xlnx,zynqmp-reset", },
98 	{ /* sentinel */ },
99 };
100 
101 static struct platform_driver zynqmp_reset_driver = {
102 	.probe	= zynqmp_reset_probe,
103 	.driver = {
104 		.name		= KBUILD_MODNAME,
105 		.of_match_table	= zynqmp_reset_dt_ids,
106 	},
107 };
108 
109 static int __init zynqmp_reset_init(void)
110 {
111 	return platform_driver_register(&zynqmp_reset_driver);
112 }
113 
114 arch_initcall(zynqmp_reset_init);
115