xref: /linux/drivers/hwspinlock/qcom_hwspinlock.c (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2013, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2015, Sony Mobile Communications AB
5  */
6 
7 #include <linux/hwspinlock.h>
8 #include <linux/io.h>
9 #include <linux/kernel.h>
10 #include <linux/mfd/syscon.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_device.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
16 
17 #include "hwspinlock_internal.h"
18 
19 #define QCOM_MUTEX_APPS_PROC_ID	1
20 #define QCOM_MUTEX_NUM_LOCKS	32
21 
22 struct qcom_hwspinlock_of_data {
23 	u32 offset;
24 	u32 stride;
25 	const struct regmap_config *regmap_config;
26 };
27 
28 static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
29 {
30 	struct regmap_field *field = lock->priv;
31 	u32 lock_owner;
32 	int ret;
33 
34 	ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
35 	if (ret)
36 		return ret;
37 
38 	ret = regmap_field_read(field, &lock_owner);
39 	if (ret)
40 		return ret;
41 
42 	return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
43 }
44 
45 static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
46 {
47 	struct regmap_field *field = lock->priv;
48 	u32 lock_owner;
49 	int ret;
50 
51 	ret = regmap_field_read(field, &lock_owner);
52 	if (ret) {
53 		pr_err("%s: unable to query spinlock owner\n", __func__);
54 		return;
55 	}
56 
57 	if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {
58 		pr_err("%s: spinlock not owned by us (actual owner is %d)\n",
59 				__func__, lock_owner);
60 	}
61 
62 	ret = regmap_field_write(field, 0);
63 	if (ret)
64 		pr_err("%s: failed to unlock spinlock\n", __func__);
65 }
66 
67 static const struct hwspinlock_ops qcom_hwspinlock_ops = {
68 	.trylock	= qcom_hwspinlock_trylock,
69 	.unlock		= qcom_hwspinlock_unlock,
70 };
71 
72 static const struct regmap_config sfpb_mutex_config = {
73 	.reg_bits		= 32,
74 	.reg_stride		= 4,
75 	.val_bits		= 32,
76 	.max_register		= 0x100,
77 	.fast_io		= true,
78 };
79 
80 static const struct qcom_hwspinlock_of_data of_sfpb_mutex = {
81 	.offset = 0x4,
82 	.stride = 0x4,
83 	.regmap_config = &sfpb_mutex_config,
84 };
85 
86 static const struct regmap_config tcsr_msm8226_mutex_config = {
87 	.reg_bits		= 32,
88 	.reg_stride		= 4,
89 	.val_bits		= 32,
90 	.max_register		= 0x1000,
91 	.fast_io		= true,
92 };
93 
94 static const struct qcom_hwspinlock_of_data of_msm8226_tcsr_mutex = {
95 	.offset = 0,
96 	.stride = 0x80,
97 	.regmap_config = &tcsr_msm8226_mutex_config,
98 };
99 
100 static const struct regmap_config tcsr_mutex_config = {
101 	.reg_bits		= 32,
102 	.reg_stride		= 4,
103 	.val_bits		= 32,
104 	.max_register		= 0x20000,
105 	.fast_io		= true,
106 };
107 
108 static const struct qcom_hwspinlock_of_data of_tcsr_mutex = {
109 	.offset = 0,
110 	.stride = 0x1000,
111 	.regmap_config = &tcsr_mutex_config,
112 };
113 
114 static const struct of_device_id qcom_hwspinlock_of_match[] = {
115 	{ .compatible = "qcom,sfpb-mutex", .data = &of_sfpb_mutex },
116 	{ .compatible = "qcom,tcsr-mutex", .data = &of_tcsr_mutex },
117 	{ .compatible = "qcom,apq8084-tcsr-mutex", .data = &of_msm8226_tcsr_mutex },
118 	{ .compatible = "qcom,msm8226-tcsr-mutex", .data = &of_msm8226_tcsr_mutex },
119 	{ .compatible = "qcom,msm8974-tcsr-mutex", .data = &of_msm8226_tcsr_mutex },
120 	{ .compatible = "qcom,msm8994-tcsr-mutex", .data = &of_msm8226_tcsr_mutex },
121 	{ }
122 };
123 MODULE_DEVICE_TABLE(of, qcom_hwspinlock_of_match);
124 
125 static struct regmap *qcom_hwspinlock_probe_syscon(struct platform_device *pdev,
126 						   u32 *base, u32 *stride)
127 {
128 	struct device_node *syscon;
129 	struct regmap *regmap;
130 	int ret;
131 
132 	syscon = of_parse_phandle(pdev->dev.of_node, "syscon", 0);
133 	if (!syscon)
134 		return ERR_PTR(-ENODEV);
135 
136 	regmap = syscon_node_to_regmap(syscon);
137 	of_node_put(syscon);
138 	if (IS_ERR(regmap))
139 		return regmap;
140 
141 	ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 1, base);
142 	if (ret < 0) {
143 		dev_err(&pdev->dev, "no offset in syscon\n");
144 		return ERR_PTR(-EINVAL);
145 	}
146 
147 	ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 2, stride);
148 	if (ret < 0) {
149 		dev_err(&pdev->dev, "no stride syscon\n");
150 		return ERR_PTR(-EINVAL);
151 	}
152 
153 	return regmap;
154 }
155 
156 static struct regmap *qcom_hwspinlock_probe_mmio(struct platform_device *pdev,
157 						 u32 *offset, u32 *stride)
158 {
159 	const struct qcom_hwspinlock_of_data *data;
160 	struct device *dev = &pdev->dev;
161 	void __iomem *base;
162 
163 	data = of_device_get_match_data(dev);
164 	if (!data->regmap_config)
165 		return ERR_PTR(-EINVAL);
166 
167 	*offset = data->offset;
168 	*stride = data->stride;
169 
170 	base = devm_platform_ioremap_resource(pdev, 0);
171 	if (IS_ERR(base))
172 		return ERR_CAST(base);
173 
174 	return devm_regmap_init_mmio(dev, base, data->regmap_config);
175 }
176 
177 static int qcom_hwspinlock_probe(struct platform_device *pdev)
178 {
179 	struct hwspinlock_device *bank;
180 	struct reg_field field;
181 	struct regmap *regmap;
182 	size_t array_size;
183 	u32 stride;
184 	u32 base;
185 	int i;
186 
187 	regmap = qcom_hwspinlock_probe_syscon(pdev, &base, &stride);
188 	if (IS_ERR(regmap) && PTR_ERR(regmap) == -ENODEV)
189 		regmap = qcom_hwspinlock_probe_mmio(pdev, &base, &stride);
190 
191 	if (IS_ERR(regmap))
192 		return PTR_ERR(regmap);
193 
194 	array_size = QCOM_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
195 	bank = devm_kzalloc(&pdev->dev, sizeof(*bank) + array_size, GFP_KERNEL);
196 	if (!bank)
197 		return -ENOMEM;
198 
199 	platform_set_drvdata(pdev, bank);
200 
201 	for (i = 0; i < QCOM_MUTEX_NUM_LOCKS; i++) {
202 		field.reg = base + i * stride;
203 		field.lsb = 0;
204 		field.msb = 31;
205 
206 		bank->lock[i].priv = devm_regmap_field_alloc(&pdev->dev,
207 							     regmap, field);
208 		if (IS_ERR(bank->lock[i].priv))
209 			return PTR_ERR(bank->lock[i].priv);
210 	}
211 
212 	return devm_hwspin_lock_register(&pdev->dev, bank, &qcom_hwspinlock_ops,
213 					 0, QCOM_MUTEX_NUM_LOCKS);
214 }
215 
216 static struct platform_driver qcom_hwspinlock_driver = {
217 	.probe		= qcom_hwspinlock_probe,
218 	.driver		= {
219 		.name	= "qcom_hwspinlock",
220 		.of_match_table = qcom_hwspinlock_of_match,
221 	},
222 };
223 
224 static int __init qcom_hwspinlock_init(void)
225 {
226 	return platform_driver_register(&qcom_hwspinlock_driver);
227 }
228 /* board init code might need to reserve hwspinlocks for predefined purposes */
229 postcore_initcall(qcom_hwspinlock_init);
230 
231 static void __exit qcom_hwspinlock_exit(void)
232 {
233 	platform_driver_unregister(&qcom_hwspinlock_driver);
234 }
235 module_exit(qcom_hwspinlock_exit);
236 
237 MODULE_LICENSE("GPL v2");
238 MODULE_DESCRIPTION("Hardware spinlock driver for Qualcomm SoCs");
239