[linux-2.6-block.git] / drivers / hwspinlock / sprd_hwspinlock.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Spreadtrum hardware spinlock driver
 * Copyright (C) 2017 Spreadtrum  - http://www.spreadtrum.com
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/hwspinlock.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>

#include "hwspinlock_internal.h"

/* hwspinlock registers definition */
#define HWSPINLOCK_RECCTRL		0x4
#define HWSPINLOCK_MASTERID(_X_)	(0x80 + 0x4 * (_X_))
#define HWSPINLOCK_TOKEN(_X_)		(0x800 + 0x4 * (_X_))

/* unlocked value */
#define HWSPINLOCK_NOTTAKEN		0x55aa10c5
/* bits definition of RECCTRL reg */
#define HWSPINLOCK_USER_BITS		0x1

/* hwspinlock number */
#define SPRD_HWLOCKS_NUM		32

struct sprd_hwspinlock_dev {
	void __iomem *base;
	struct clk *clk;
	struct hwspinlock_device bank;
};

/* try to lock the hardware spinlock */
static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
{
	struct sprd_hwspinlock_dev *sprd_hwlock =
		dev_get_drvdata(lock->bank->dev);
	void __iomem *addr = lock->priv;
	int user_id, lock_id;

	if (!readl(addr))
		return 1;

	lock_id = hwlock_to_id(lock);
	/* get the hardware spinlock master/user id */
	user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
	dev_warn(sprd_hwlock->bank.dev,
		 "hwspinlock [%d] lock failed and master/user id = %d!\n",
		 lock_id, user_id);
	return 0;
}

/* unlock the hardware spinlock */
static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	writel(HWSPINLOCK_NOTTAKEN, lock_addr);
}

/* The specs recommended below number as the retry delay time */
static void sprd_hwspinlock_relax(struct hwspinlock *lock)
{
	ndelay(10);
}

static const struct hwspinlock_ops sprd_hwspinlock_ops = {
	.trylock = sprd_hwspinlock_trylock,
	.unlock = sprd_hwspinlock_unlock,
	.relax = sprd_hwspinlock_relax,
};

static int sprd_hwspinlock_probe(struct platform_device *pdev)
{
	struct sprd_hwspinlock_dev *sprd_hwlock;
	struct hwspinlock *lock;
	struct resource *res;
	int i, ret;

	if (!pdev->dev.of_node)
		return -ENODEV;

	sprd_hwlock = devm_kzalloc(&pdev->dev,
				   sizeof(struct sprd_hwspinlock_dev) +
				   SPRD_HWLOCKS_NUM * sizeof(*lock),
				   GFP_KERNEL);
	if (!sprd_hwlock)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	sprd_hwlock->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(sprd_hwlock->base))
		return PTR_ERR(sprd_hwlock->base);

	sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
	if (IS_ERR(sprd_hwlock->clk)) {
		dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
		return PTR_ERR(sprd_hwlock->clk);
	}

	clk_prepare_enable(sprd_hwlock->clk);

	/* set the hwspinlock to record user id to identify subsystems */
	writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);

	for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
		lock = &sprd_hwlock->bank.lock[i];
		lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
	}

	platform_set_drvdata(pdev, sprd_hwlock);
	pm_runtime_enable(&pdev->dev);

	ret = hwspin_lock_register(&sprd_hwlock->bank, &pdev->dev,
				   &sprd_hwspinlock_ops, 0, SPRD_HWLOCKS_NUM);
	if (ret) {
		pm_runtime_disable(&pdev->dev);
		clk_disable_unprepare(sprd_hwlock->clk);
		return ret;
	}

	return 0;
}

static int sprd_hwspinlock_remove(struct platform_device *pdev)
{
	struct sprd_hwspinlock_dev *sprd_hwlock = platform_get_drvdata(pdev);

	hwspin_lock_unregister(&sprd_hwlock->bank);
	pm_runtime_disable(&pdev->dev);
	clk_disable_unprepare(sprd_hwlock->clk);
	return 0;
}

static const struct of_device_id sprd_hwspinlock_of_match[] = {
	{ .compatible = "sprd,hwspinlock-r3p0", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);

static struct platform_driver sprd_hwspinlock_driver = {
	.probe = sprd_hwspinlock_probe,
	.remove = sprd_hwspinlock_remove,
	.driver = {
		.name = "sprd_hwspinlock",
		.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
	},
};

static int __init sprd_hwspinlock_init(void)
{
	return platform_driver_register(&sprd_hwspinlock_driver);
}
postcore_initcall(sprd_hwspinlock_init);

static void __exit sprd_hwspinlock_exit(void)
{
	platform_driver_unregister(&sprd_hwspinlock_driver);
}
module_exit(sprd_hwspinlock_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");
Commit	Line	Data
0c3e890b	1	// SPDX-License-Identifier: GPL-2.0
d8c8bbbb BW	2	/*
	3	* Spreadtrum hardware spinlock driver
	4	* Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
d8c8bbbb BW	5	*/
	6
	7	#include <linux/bitops.h>
	8	#include <linux/clk.h>
	9	#include <linux/delay.h>
	10	#include <linux/device.h>
	11	#include <linux/hwspinlock.h>
	12	#include <linux/io.h>
	13	#include <linux/kernel.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/of_device.h>
	17	#include <linux/platform_device.h>
	18	#include <linux/pm_runtime.h>
	19	#include <linux/slab.h>
	20
	21	#include "hwspinlock_internal.h"
	22
	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_))
	27
	28	/* unlocked value */
	29	#define HWSPINLOCK_NOTTAKEN 0x55aa10c5
	30	/* bits definition of RECCTRL reg */
	31	#define HWSPINLOCK_USER_BITS 0x1
	32
	33	/* hwspinlock number */
	34	#define SPRD_HWLOCKS_NUM 32
	35
	36	struct sprd_hwspinlock_dev {
	37	void __iomem *base;
	38	struct clk *clk;
	39	struct hwspinlock_device bank;
	40	};
	41
	42	/* try to lock the hardware spinlock */
	43	static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
	44	{
	45	struct sprd_hwspinlock_dev *sprd_hwlock =
	46	dev_get_drvdata(lock->bank->dev);
	47	void __iomem *addr = lock->priv;
	48	int user_id, lock_id;
	49
	50	if (!readl(addr))
	51	return 1;
	52
	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",
	58	lock_id, user_id);
	59	return 0;
	60	}
	61
	62	/* unlock the hardware spinlock */
	63	static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
	64	{
	65	void __iomem *lock_addr = lock->priv;
	66
	67	writel(HWSPINLOCK_NOTTAKEN, lock_addr);
	68	}
69
70	/* The specs recommended below number as the retry delay time */
71	static void sprd_hwspinlock_relax(struct hwspinlock *lock)
72	{
73	ndelay(10);
74	}
75
76	static const struct hwspinlock_ops sprd_hwspinlock_ops = {
77	.trylock = sprd_hwspinlock_trylock,
78	.unlock = sprd_hwspinlock_unlock,
79	.relax = sprd_hwspinlock_relax,
80	};
81
82	static int sprd_hwspinlock_probe(struct platform_device *pdev)
83	{
84	struct sprd_hwspinlock_dev *sprd_hwlock;
85	struct hwspinlock *lock;
86	struct resource *res;
87	int i, ret;
88
89	if (!pdev->dev.of_node)
90	return -ENODEV;
91
92	sprd_hwlock = devm_kzalloc(&pdev->dev,
93	sizeof(struct sprd_hwspinlock_dev) +
94	SPRD_HWLOCKS_NUM * sizeof(*lock),
95	GFP_KERNEL);
96	if (!sprd_hwlock)
97	return -ENOMEM;
98
99	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
100	sprd_hwlock->base = devm_ioremap_resource(&pdev->dev, res);
101	if (IS_ERR(sprd_hwlock->base))
102	return PTR_ERR(sprd_hwlock->base);
103
104	sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
105	if (IS_ERR(sprd_hwlock->clk)) {
106	dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
107	return PTR_ERR(sprd_hwlock->clk);
108	}
109
110	clk_prepare_enable(sprd_hwlock->clk);
111
112	/* set the hwspinlock to record user id to identify subsystems */
113	writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);
114
115	for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
116	lock = &sprd_hwlock->bank.lock[i];
117	lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
118	}
119
120	platform_set_drvdata(pdev, sprd_hwlock);
121	pm_runtime_enable(&pdev->dev);
122
123	ret = hwspin_lock_register(&sprd_hwlock->bank, &pdev->dev,
124	&sprd_hwspinlock_ops, 0, SPRD_HWLOCKS_NUM);
125	if (ret) {
126	pm_runtime_disable(&pdev->dev);
127	clk_disable_unprepare(sprd_hwlock->clk);
128	return ret;
129	}
130
131	return 0;
132	}
133
134	static int sprd_hwspinlock_remove(struct platform_device *pdev)
135	{
136	struct sprd_hwspinlock_dev *sprd_hwlock = platform_get_drvdata(pdev);
137
138	hwspin_lock_unregister(&sprd_hwlock->bank);
139	pm_runtime_disable(&pdev->dev);
140	clk_disable_unprepare(sprd_hwlock->clk);
141	return 0;
142	}
143
144	static const struct of_device_id sprd_hwspinlock_of_match[] = {
145	{ .compatible = "sprd,hwspinlock-r3p0", },
146	{ /* sentinel */ }
147	};
148	MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);
149
150	static struct platform_driver sprd_hwspinlock_driver = {
151	.probe = sprd_hwspinlock_probe,
152	.remove = sprd_hwspinlock_remove,
153	.driver = {
154	.name = "sprd_hwspinlock",
155	.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
156	},
157	};
158
159	static int __init sprd_hwspinlock_init(void)
160	{
161	return platform_driver_register(&sprd_hwspinlock_driver);
162	}
163	postcore_initcall(sprd_hwspinlock_init);
164
165	static void __exit sprd_hwspinlock_exit(void)
166	{
167	platform_driver_unregister(&sprd_hwspinlock_driver);
168	}
169	module_exit(sprd_hwspinlock_exit);
170
171	MODULE_LICENSE("GPL v2");
172	MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
173	MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
174	MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
175	MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");