1 // SPDX-License-Identifier: GPL-2.0
3 * Spreadtrum hardware spinlock driver
4 * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
7 #include <linux/bitops.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/hwspinlock.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/slab.h>
21 #include "hwspinlock_internal.h"
23 /* hwspinlock registers definition */
24 #define HWSPINLOCK_RECCTRL 0x4
25 #define HWSPINLOCK_MASTERID(_X_) (0x80 + 0x4 * (_X_))
26 #define HWSPINLOCK_TOKEN(_X_) (0x800 + 0x4 * (_X_))
29 #define HWSPINLOCK_NOTTAKEN 0x55aa10c5
30 /* bits definition of RECCTRL reg */
31 #define HWSPINLOCK_USER_BITS 0x1
33 /* hwspinlock number */
34 #define SPRD_HWLOCKS_NUM 32
36 struct sprd_hwspinlock_dev {
39 struct hwspinlock_device bank;
42 /* try to lock the hardware spinlock */
43 static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
45 struct sprd_hwspinlock_dev *sprd_hwlock =
46 dev_get_drvdata(lock->bank->dev);
47 void __iomem *addr = lock->priv;
53 lock_id = hwlock_to_id(lock);
54 /* get the hardware spinlock master/user id */
55 user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
56 dev_warn(sprd_hwlock->bank.dev,
57 "hwspinlock [%d] lock failed and master/user id = %d!\n",
62 /* unlock the hardware spinlock */
63 static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
65 void __iomem *lock_addr = lock->priv;
67 writel(HWSPINLOCK_NOTTAKEN, lock_addr);
70 /* The specs recommended below number as the retry delay time */
71 static void sprd_hwspinlock_relax(struct hwspinlock *lock)
76 static const struct hwspinlock_ops sprd_hwspinlock_ops = {
77 .trylock = sprd_hwspinlock_trylock,
78 .unlock = sprd_hwspinlock_unlock,
79 .relax = sprd_hwspinlock_relax,
82 static void sprd_hwspinlock_disable(void *data)
84 struct sprd_hwspinlock_dev *sprd_hwlock = data;
86 clk_disable_unprepare(sprd_hwlock->clk);
89 static int sprd_hwspinlock_probe(struct platform_device *pdev)
91 struct sprd_hwspinlock_dev *sprd_hwlock;
92 struct hwspinlock *lock;
95 if (!pdev->dev.of_node)
98 sprd_hwlock = devm_kzalloc(&pdev->dev,
99 sizeof(struct sprd_hwspinlock_dev) +
100 SPRD_HWLOCKS_NUM * sizeof(*lock),
105 sprd_hwlock->base = devm_platform_ioremap_resource(pdev, 0);
106 if (IS_ERR(sprd_hwlock->base))
107 return PTR_ERR(sprd_hwlock->base);
109 sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
110 if (IS_ERR(sprd_hwlock->clk)) {
111 dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
112 return PTR_ERR(sprd_hwlock->clk);
115 ret = clk_prepare_enable(sprd_hwlock->clk);
119 ret = devm_add_action_or_reset(&pdev->dev, sprd_hwspinlock_disable,
123 "Failed to add hwspinlock disable action\n");
127 /* set the hwspinlock to record user id to identify subsystems */
128 writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);
130 for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
131 lock = &sprd_hwlock->bank.lock[i];
132 lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
135 platform_set_drvdata(pdev, sprd_hwlock);
136 pm_runtime_enable(&pdev->dev);
138 ret = hwspin_lock_register(&sprd_hwlock->bank, &pdev->dev,
139 &sprd_hwspinlock_ops, 0, SPRD_HWLOCKS_NUM);
141 pm_runtime_disable(&pdev->dev);
148 static int sprd_hwspinlock_remove(struct platform_device *pdev)
150 struct sprd_hwspinlock_dev *sprd_hwlock = platform_get_drvdata(pdev);
152 hwspin_lock_unregister(&sprd_hwlock->bank);
153 pm_runtime_disable(&pdev->dev);
157 static const struct of_device_id sprd_hwspinlock_of_match[] = {
158 { .compatible = "sprd,hwspinlock-r3p0", },
161 MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);
163 static struct platform_driver sprd_hwspinlock_driver = {
164 .probe = sprd_hwspinlock_probe,
165 .remove = sprd_hwspinlock_remove,
167 .name = "sprd_hwspinlock",
168 .of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
172 static int __init sprd_hwspinlock_init(void)
174 return platform_driver_register(&sprd_hwspinlock_driver);
176 postcore_initcall(sprd_hwspinlock_init);
178 static void __exit sprd_hwspinlock_exit(void)
180 platform_driver_unregister(&sprd_hwspinlock_driver);
182 module_exit(sprd_hwspinlock_exit);
184 MODULE_LICENSE("GPL v2");
185 MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
186 MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
187 MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
188 MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");