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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
22static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
23{
24 struct regmap_field *field = lock->priv;
25 u32 lock_owner;
26 int ret;
27
28 ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
29 if (ret)
30 return ret;
31
32 ret = regmap_field_read(field, &lock_owner);
33 if (ret)
34 return ret;
35
36 return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
37}
38
39static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
40{
41 struct regmap_field *field = lock->priv;
42 u32 lock_owner;
43 int ret;
44
45 ret = regmap_field_read(field, &lock_owner);
46 if (ret) {
47 pr_err("%s: unable to query spinlock owner\n", __func__);
48 return;
49 }
50
51 if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {
52 pr_err("%s: spinlock not owned by us (actual owner is %d)\n",
53 __func__, lock_owner);
54 }
55
56 ret = regmap_field_write(field, 0);
57 if (ret)
58 pr_err("%s: failed to unlock spinlock\n", __func__);
59}
60
61static const struct hwspinlock_ops qcom_hwspinlock_ops = {
62 .trylock = qcom_hwspinlock_trylock,
63 .unlock = qcom_hwspinlock_unlock,
64};
65
66static const struct of_device_id qcom_hwspinlock_of_match[] = {
67 { .compatible = "qcom,sfpb-mutex" },
68 { .compatible = "qcom,tcsr-mutex" },
69 { }
70};
71MODULE_DEVICE_TABLE(of, qcom_hwspinlock_of_match);
72
73static struct regmap *qcom_hwspinlock_probe_syscon(struct platform_device *pdev,
74 u32 *base, u32 *stride)
75{
76 struct device_node *syscon;
77 struct regmap *regmap;
78 int ret;
79
80 syscon = of_parse_phandle(pdev->dev.of_node, "syscon", 0);
81 if (!syscon)
82 return ERR_PTR(-ENODEV);
83
84 regmap = syscon_node_to_regmap(syscon);
85 of_node_put(syscon);
86 if (IS_ERR(regmap))
87 return regmap;
88
89 ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 1, base);
90 if (ret < 0) {
91 dev_err(&pdev->dev, "no offset in syscon\n");
92 return ERR_PTR(-EINVAL);
93 }
94
95 ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 2, stride);
96 if (ret < 0) {
97 dev_err(&pdev->dev, "no stride syscon\n");
98 return ERR_PTR(-EINVAL);
99 }
100
101 return regmap;
102}
103
104static const struct regmap_config tcsr_mutex_config = {
105 .reg_bits = 32,
106 .reg_stride = 4,
107 .val_bits = 32,
108 .max_register = 0x40000,
109 .fast_io = true,
110};
111
112static struct regmap *qcom_hwspinlock_probe_mmio(struct platform_device *pdev,
113 u32 *offset, u32 *stride)
114{
115 struct device *dev = &pdev->dev;
116 void __iomem *base;
117
118
119 *offset = 0;
120 *stride = 0x1000;
121
122 base = devm_platform_ioremap_resource(pdev, 0);
123 if (IS_ERR(base))
124 return ERR_CAST(base);
125
126 return devm_regmap_init_mmio(dev, base, &tcsr_mutex_config);
127}
128
129static int qcom_hwspinlock_probe(struct platform_device *pdev)
130{
131 struct hwspinlock_device *bank;
132 struct reg_field field;
133 struct regmap *regmap;
134 size_t array_size;
135 u32 stride;
136 u32 base;
137 int i;
138
139 regmap = qcom_hwspinlock_probe_syscon(pdev, &base, &stride);
140 if (IS_ERR(regmap) && PTR_ERR(regmap) == -ENODEV)
141 regmap = qcom_hwspinlock_probe_mmio(pdev, &base, &stride);
142
143 if (IS_ERR(regmap))
144 return PTR_ERR(regmap);
145
146 array_size = QCOM_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
147 bank = devm_kzalloc(&pdev->dev, sizeof(*bank) + array_size, GFP_KERNEL);
148 if (!bank)
149 return -ENOMEM;
150
151 platform_set_drvdata(pdev, bank);
152
153 for (i = 0; i < QCOM_MUTEX_NUM_LOCKS; i++) {
154 field.reg = base + i * stride;
155 field.lsb = 0;
156 field.msb = 31;
157
158 bank->lock[i].priv = devm_regmap_field_alloc(&pdev->dev,
159 regmap, field);
160 }
161
162 return devm_hwspin_lock_register(&pdev->dev, bank, &qcom_hwspinlock_ops,
163 0, QCOM_MUTEX_NUM_LOCKS);
164}
165
166static struct platform_driver qcom_hwspinlock_driver = {
167 .probe = qcom_hwspinlock_probe,
168 .driver = {
169 .name = "qcom_hwspinlock",
170 .of_match_table = qcom_hwspinlock_of_match,
171 },
172};
173
174static int __init qcom_hwspinlock_init(void)
175{
176 return platform_driver_register(&qcom_hwspinlock_driver);
177}
178
179postcore_initcall(qcom_hwspinlock_init);
180
181static void __exit qcom_hwspinlock_exit(void)
182{
183 platform_driver_unregister(&qcom_hwspinlock_driver);
184}
185module_exit(qcom_hwspinlock_exit);
186
187MODULE_LICENSE("GPL v2");
188MODULE_DESCRIPTION("Hardware spinlock driver for Qualcomm SoCs");
189
