blob: fa6880b8060a050cf2ef01d8a79b762e1cb2272c [file] [log] [blame]
Bjorn Andersson19a0f612015-03-24 10:11:05 -07001/*
2 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
3 * Copyright (c) 2015, Sony Mobile Communications AB
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/hwspinlock.h>
16#include <linux/io.h>
17#include <linux/kernel.h>
18#include <linux/mfd/syscon.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/of_device.h>
22#include <linux/platform_device.h>
23#include <linux/pm_runtime.h>
24#include <linux/regmap.h>
25
26#include "hwspinlock_internal.h"
27
28#define QCOM_MUTEX_APPS_PROC_ID 1
29#define QCOM_MUTEX_NUM_LOCKS 32
30
31static int qcom_hwspinlock_trylock(struct hwspinlock *lock)
32{
33 struct regmap_field *field = lock->priv;
34 u32 lock_owner;
35 int ret;
36
37 ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);
38 if (ret)
39 return ret;
40
41 ret = regmap_field_read(field, &lock_owner);
42 if (ret)
43 return ret;
44
45 return lock_owner == QCOM_MUTEX_APPS_PROC_ID;
46}
47
48static void qcom_hwspinlock_unlock(struct hwspinlock *lock)
49{
50 struct regmap_field *field = lock->priv;
51 u32 lock_owner;
52 int ret;
53
54 ret = regmap_field_read(field, &lock_owner);
55 if (ret) {
56 pr_err("%s: unable to query spinlock owner\n", __func__);
57 return;
58 }
59
60 if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {
61 pr_err("%s: spinlock not owned by us (actual owner is %d)\n",
62 __func__, lock_owner);
63 }
64
65 ret = regmap_field_write(field, 0);
66 if (ret)
67 pr_err("%s: failed to unlock spinlock\n", __func__);
68}
69
70static const struct hwspinlock_ops qcom_hwspinlock_ops = {
71 .trylock = qcom_hwspinlock_trylock,
72 .unlock = qcom_hwspinlock_unlock,
73};
74
75static const struct of_device_id qcom_hwspinlock_of_match[] = {
76 { .compatible = "qcom,sfpb-mutex" },
77 { .compatible = "qcom,tcsr-mutex" },
78 { }
79};
80MODULE_DEVICE_TABLE(of, qcom_hwspinlock_of_match);
81
82static int qcom_hwspinlock_probe(struct platform_device *pdev)
83{
84 struct hwspinlock_device *bank;
85 struct device_node *syscon;
86 struct reg_field field;
87 struct regmap *regmap;
88 size_t array_size;
89 u32 stride;
90 u32 base;
91 int ret;
92 int i;
93
94 syscon = of_parse_phandle(pdev->dev.of_node, "syscon", 0);
95 if (!syscon) {
96 dev_err(&pdev->dev, "no syscon property\n");
97 return -ENODEV;
98 }
99
100 regmap = syscon_node_to_regmap(syscon);
Peter Chen4d41c8c2016-07-05 10:11:03 +0800101 of_node_put(syscon);
Bjorn Andersson19a0f612015-03-24 10:11:05 -0700102 if (IS_ERR(regmap))
103 return PTR_ERR(regmap);
104
105 ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 1, &base);
106 if (ret < 0) {
107 dev_err(&pdev->dev, "no offset in syscon\n");
108 return -EINVAL;
109 }
110
111 ret = of_property_read_u32_index(pdev->dev.of_node, "syscon", 2, &stride);
112 if (ret < 0) {
113 dev_err(&pdev->dev, "no stride syscon\n");
114 return -EINVAL;
115 }
116
117 array_size = QCOM_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);
118 bank = devm_kzalloc(&pdev->dev, sizeof(*bank) + array_size, GFP_KERNEL);
119 if (!bank)
120 return -ENOMEM;
121
122 platform_set_drvdata(pdev, bank);
123
124 for (i = 0; i < QCOM_MUTEX_NUM_LOCKS; i++) {
125 field.reg = base + i * stride;
126 field.lsb = 0;
Bjorn Anderssonbd5717a2015-06-26 14:47:21 -0700127 field.msb = 31;
Bjorn Andersson19a0f612015-03-24 10:11:05 -0700128
129 bank->lock[i].priv = devm_regmap_field_alloc(&pdev->dev,
130 regmap, field);
131 }
132
133 pm_runtime_enable(&pdev->dev);
134
135 ret = hwspin_lock_register(bank, &pdev->dev, &qcom_hwspinlock_ops,
136 0, QCOM_MUTEX_NUM_LOCKS);
137 if (ret)
138 pm_runtime_disable(&pdev->dev);
139
140 return ret;
141}
142
143static int qcom_hwspinlock_remove(struct platform_device *pdev)
144{
145 struct hwspinlock_device *bank = platform_get_drvdata(pdev);
146 int ret;
147
148 ret = hwspin_lock_unregister(bank);
149 if (ret) {
150 dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
151 return ret;
152 }
153
154 pm_runtime_disable(&pdev->dev);
155
156 return 0;
157}
158
159static struct platform_driver qcom_hwspinlock_driver = {
160 .probe = qcom_hwspinlock_probe,
161 .remove = qcom_hwspinlock_remove,
162 .driver = {
163 .name = "qcom_hwspinlock",
164 .of_match_table = qcom_hwspinlock_of_match,
165 },
166};
167
168static int __init qcom_hwspinlock_init(void)
169{
170 return platform_driver_register(&qcom_hwspinlock_driver);
171}
172/* board init code might need to reserve hwspinlocks for predefined purposes */
173postcore_initcall(qcom_hwspinlock_init);
174
175static void __exit qcom_hwspinlock_exit(void)
176{
177 platform_driver_unregister(&qcom_hwspinlock_driver);
178}
179module_exit(qcom_hwspinlock_exit);
180
181MODULE_LICENSE("GPL v2");
182MODULE_DESCRIPTION("Hardware spinlock driver for Qualcomm SoCs");