1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2018 The Linux Foundation. All rights reserved.
4 */
5
6 #include <linux/module.h>
7 #include <linux/platform_device.h>
8 #include <linux/reset-controller.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/of_device.h>
12 #include <dt-bindings/reset/qcom,sdm845-aoss.h>
13
14 struct qcom_aoss_reset_map {
15 unsigned int reg;
16 };
17
18 struct qcom_aoss_desc {
19 const struct qcom_aoss_reset_map *resets;
20 size_t num_resets;
21 };
22
23 struct qcom_aoss_reset_data {
24 struct reset_controller_dev rcdev;
25 void __iomem *base;
26 const struct qcom_aoss_desc *desc;
27 };
28
29 static const struct qcom_aoss_reset_map sdm845_aoss_resets[] = {
30 [AOSS_CC_MSS_RESTART] = {0x10000},
31 [AOSS_CC_CAMSS_RESTART] = {0x11000},
32 [AOSS_CC_VENUS_RESTART] = {0x12000},
33 [AOSS_CC_GPU_RESTART] = {0x13000},
34 [AOSS_CC_DISPSS_RESTART] = {0x14000},
35 [AOSS_CC_WCSS_RESTART] = {0x20000},
36 [AOSS_CC_LPASS_RESTART] = {0x30000},
37 };
38
39 static const struct qcom_aoss_desc sdm845_aoss_desc = {
40 .resets = sdm845_aoss_resets,
41 .num_resets = ARRAY_SIZE(sdm845_aoss_resets),
42 };
43
to_qcom_aoss_reset_data(struct reset_controller_dev * rcdev)44 static inline struct qcom_aoss_reset_data *to_qcom_aoss_reset_data(
45 struct reset_controller_dev *rcdev)
46 {
47 return container_of(rcdev, struct qcom_aoss_reset_data, rcdev);
48 }
49
qcom_aoss_control_assert(struct reset_controller_dev * rcdev,unsigned long idx)50 static int qcom_aoss_control_assert(struct reset_controller_dev *rcdev,
51 unsigned long idx)
52 {
53 struct qcom_aoss_reset_data *data = to_qcom_aoss_reset_data(rcdev);
54 const struct qcom_aoss_reset_map *map = &data->desc->resets[idx];
55
56 writel(1, data->base + map->reg);
57 /* Wait 6 32kHz sleep cycles for reset */
58 usleep_range(200, 300);
59 return 0;
60 }
61
qcom_aoss_control_deassert(struct reset_controller_dev * rcdev,unsigned long idx)62 static int qcom_aoss_control_deassert(struct reset_controller_dev *rcdev,
63 unsigned long idx)
64 {
65 struct qcom_aoss_reset_data *data = to_qcom_aoss_reset_data(rcdev);
66 const struct qcom_aoss_reset_map *map = &data->desc->resets[idx];
67
68 writel(0, data->base + map->reg);
69 /* Wait 6 32kHz sleep cycles for reset */
70 usleep_range(200, 300);
71 return 0;
72 }
73
qcom_aoss_control_reset(struct reset_controller_dev * rcdev,unsigned long idx)74 static int qcom_aoss_control_reset(struct reset_controller_dev *rcdev,
75 unsigned long idx)
76 {
77 qcom_aoss_control_assert(rcdev, idx);
78
79 return qcom_aoss_control_deassert(rcdev, idx);
80 }
81
82 static const struct reset_control_ops qcom_aoss_reset_ops = {
83 .reset = qcom_aoss_control_reset,
84 .assert = qcom_aoss_control_assert,
85 .deassert = qcom_aoss_control_deassert,
86 };
87
qcom_aoss_reset_probe(struct platform_device * pdev)88 static int qcom_aoss_reset_probe(struct platform_device *pdev)
89 {
90 struct qcom_aoss_reset_data *data;
91 struct device *dev = &pdev->dev;
92 const struct qcom_aoss_desc *desc;
93 struct resource *res;
94
95 desc = of_device_get_match_data(dev);
96 if (!desc)
97 return -EINVAL;
98
99 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
100 if (!data)
101 return -ENOMEM;
102
103 data->desc = desc;
104 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
105 data->base = devm_ioremap_resource(dev, res);
106 if (IS_ERR(data->base))
107 return PTR_ERR(data->base);
108
109 data->rcdev.owner = THIS_MODULE;
110 data->rcdev.ops = &qcom_aoss_reset_ops;
111 data->rcdev.nr_resets = desc->num_resets;
112 data->rcdev.of_node = dev->of_node;
113
114 return devm_reset_controller_register(dev, &data->rcdev);
115 }
116
117 static const struct of_device_id qcom_aoss_reset_of_match[] = {
118 { .compatible = "qcom,sdm845-aoss-cc", .data = &sdm845_aoss_desc },
119 {}
120 };
121 MODULE_DEVICE_TABLE(of, qcom_aoss_reset_of_match);
122
123 static struct platform_driver qcom_aoss_reset_driver = {
124 .probe = qcom_aoss_reset_probe,
125 .driver = {
126 .name = "qcom_aoss_reset",
127 .of_match_table = qcom_aoss_reset_of_match,
128 },
129 };
130
131 module_platform_driver(qcom_aoss_reset_driver);
132
133 MODULE_DESCRIPTION("Qualcomm AOSS Reset Driver");
134 MODULE_LICENSE("GPL v2");
135