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

/*
 * Spreadtrum hardware spinlock driver
 * Copyright (C) 2017 Spreadtrum  - http://www.spreadtrum.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 */

#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
d8c8bbbb BW	1	/*
	2	* Spreadtrum hardware spinlock driver
	3	* Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License
	7	* version 2 as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful, but
	10	* WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	* General Public License for more details.
	13	*/
	14
	15	#include <linux/bitops.h>
	16	#include <linux/clk.h>
	17	#include <linux/delay.h>
	18	#include <linux/device.h>
	19	#include <linux/hwspinlock.h>
	20	#include <linux/io.h>
	21	#include <linux/kernel.h>
	22	#include <linux/module.h>
	23	#include <linux/of.h>
	24	#include <linux/of_device.h>
	25	#include <linux/platform_device.h>
	26	#include <linux/pm_runtime.h>
	27	#include <linux/slab.h>
	28
	29	#include "hwspinlock_internal.h"
	30
	31	/* hwspinlock registers definition */
	32	#define HWSPINLOCK_RECCTRL 0x4
	33	#define HWSPINLOCK_MASTERID(_X_) (0x80 + 0x4 * (_X_))
	34	#define HWSPINLOCK_TOKEN(_X_) (0x800 + 0x4 * (_X_))
	35
	36	/* unlocked value */
	37	#define HWSPINLOCK_NOTTAKEN 0x55aa10c5
	38	/* bits definition of RECCTRL reg */
	39	#define HWSPINLOCK_USER_BITS 0x1
	40
	41	/* hwspinlock number */
	42	#define SPRD_HWLOCKS_NUM 32
	43
	44	struct sprd_hwspinlock_dev {
	45	void __iomem *base;
	46	struct clk *clk;
	47	struct hwspinlock_device bank;
	48	};
	49
	50	/* try to lock the hardware spinlock */
	51	static int sprd_hwspinlock_trylock(struct hwspinlock *lock)
	52	{
	53	struct sprd_hwspinlock_dev *sprd_hwlock =
	54	dev_get_drvdata(lock->bank->dev);
	55	void __iomem *addr = lock->priv;
	56	int user_id, lock_id;
	57
	58	if (!readl(addr))
	59	return 1;
	60
	61	lock_id = hwlock_to_id(lock);
	62	/* get the hardware spinlock master/user id */
	63	user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));
	64	dev_warn(sprd_hwlock->bank.dev,
65	"hwspinlock [%d] lock failed and master/user id = %d!\n",
66	lock_id, user_id);
67	return 0;
68	}
69
70	/* unlock the hardware spinlock */
71	static void sprd_hwspinlock_unlock(struct hwspinlock *lock)
72	{
73	void __iomem *lock_addr = lock->priv;
74
75	writel(HWSPINLOCK_NOTTAKEN, lock_addr);
76	}
77
78	/* The specs recommended below number as the retry delay time */
79	static void sprd_hwspinlock_relax(struct hwspinlock *lock)
80	{
81	ndelay(10);
82	}
83
84	static const struct hwspinlock_ops sprd_hwspinlock_ops = {
85	.trylock = sprd_hwspinlock_trylock,
86	.unlock = sprd_hwspinlock_unlock,
87	.relax = sprd_hwspinlock_relax,
88	};
89
90	static int sprd_hwspinlock_probe(struct platform_device *pdev)
91	{
92	struct sprd_hwspinlock_dev *sprd_hwlock;
93	struct hwspinlock *lock;
94	struct resource *res;
95	int i, ret;
96
97	if (!pdev->dev.of_node)
98	return -ENODEV;
99
100	sprd_hwlock = devm_kzalloc(&pdev->dev,
101	sizeof(struct sprd_hwspinlock_dev) +
102	SPRD_HWLOCKS_NUM * sizeof(*lock),
103	GFP_KERNEL);
104	if (!sprd_hwlock)
105	return -ENOMEM;
106
107	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
108	sprd_hwlock->base = devm_ioremap_resource(&pdev->dev, res);
109	if (IS_ERR(sprd_hwlock->base))
110	return PTR_ERR(sprd_hwlock->base);
111
112	sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");
113	if (IS_ERR(sprd_hwlock->clk)) {
114	dev_err(&pdev->dev, "get hwspinlock clock failed!\n");
115	return PTR_ERR(sprd_hwlock->clk);
116	}
117
118	clk_prepare_enable(sprd_hwlock->clk);
119
120	/* set the hwspinlock to record user id to identify subsystems */
121	writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);
122
123	for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {
124	lock = &sprd_hwlock->bank.lock[i];
125	lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);
126	}
127
128	platform_set_drvdata(pdev, sprd_hwlock);
129	pm_runtime_enable(&pdev->dev);
130
131	ret = hwspin_lock_register(&sprd_hwlock->bank, &pdev->dev,
132	&sprd_hwspinlock_ops, 0, SPRD_HWLOCKS_NUM);
133	if (ret) {
134	pm_runtime_disable(&pdev->dev);
135	clk_disable_unprepare(sprd_hwlock->clk);
136	return ret;
137	}
138
139	return 0;
140	}
141
142	static int sprd_hwspinlock_remove(struct platform_device *pdev)
143	{
144	struct sprd_hwspinlock_dev *sprd_hwlock = platform_get_drvdata(pdev);
145
146	hwspin_lock_unregister(&sprd_hwlock->bank);
147	pm_runtime_disable(&pdev->dev);
148	clk_disable_unprepare(sprd_hwlock->clk);
149	return 0;
150	}
151
152	static const struct of_device_id sprd_hwspinlock_of_match[] = {
153	{ .compatible = "sprd,hwspinlock-r3p0", },
154	{ /* sentinel */ }
155	};
156	MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);
157
158	static struct platform_driver sprd_hwspinlock_driver = {
159	.probe = sprd_hwspinlock_probe,
160	.remove = sprd_hwspinlock_remove,
161	.driver = {
162	.name = "sprd_hwspinlock",
163	.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
164	},
165	};
166
167	static int __init sprd_hwspinlock_init(void)
168	{
169	return platform_driver_register(&sprd_hwspinlock_driver);
170	}
171	postcore_initcall(sprd_hwspinlock_init);
172
173	static void __exit sprd_hwspinlock_exit(void)
174	{
175	platform_driver_unregister(&sprd_hwspinlock_driver);
176	}
177	module_exit(sprd_hwspinlock_exit);
178
179	MODULE_LICENSE("GPL v2");
180	MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");
181	MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
182	MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
183	MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");