[deliverable/linux.git] / arch / arm / mach-exynos / pm_domains.c

/*
 * Exynos Generic power domain support.
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com
 *
 * Implementation of Exynos specific power domain control which is used in
 * conjunction with runtime-pm. Support for both device-tree and non-device-tree
 * based power domain support is included.
 *
 * 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.
*/

#include <linux/io.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/pm_domain.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/sched.h>

#define INT_LOCAL_PWR_EN	0x7
#define MAX_CLK_PER_DOMAIN	4

/*
 * Exynos specific wrapper around the generic power domain
 */
struct exynos_pm_domain {
	void __iomem *base;
	char const *name;
	bool is_off;
	struct generic_pm_domain pd;
	struct clk *oscclk;
	struct clk *clk[MAX_CLK_PER_DOMAIN];
	struct clk *pclk[MAX_CLK_PER_DOMAIN];
};

static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
{
	struct exynos_pm_domain *pd;
	void __iomem *base;
	u32 timeout, pwr;
	char *op;

	pd = container_of(domain, struct exynos_pm_domain, pd);
	base = pd->base;

	/* Set oscclk before powering off a domain*/
	if (!power_on) {
		int i;

		for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
			if (IS_ERR(pd->clk[i]))
				break;
			if (clk_set_parent(pd->clk[i], pd->oscclk))
				pr_err("%s: error setting oscclk as parent to clock %d\n",
						pd->name, i);
		}
	}

	pwr = power_on ? INT_LOCAL_PWR_EN : 0;
	__raw_writel(pwr, base);

	/* Wait max 1ms */
	timeout = 10;

	while ((__raw_readl(base + 0x4) & INT_LOCAL_PWR_EN) != pwr) {
		if (!timeout) {
			op = (power_on) ? "enable" : "disable";
			pr_err("Power domain %s %s failed\n", domain->name, op);
			return -ETIMEDOUT;
		}
		timeout--;
		cpu_relax();
		usleep_range(80, 100);
	}

	/* Restore clocks after powering on a domain*/
	if (power_on) {
		int i;

		for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
			if (IS_ERR(pd->clk[i]))
				break;
			if (clk_set_parent(pd->clk[i], pd->pclk[i]))
				pr_err("%s: error setting parent to clock%d\n",
						pd->name, i);
		}
	}

	return 0;
}

static int exynos_pd_power_on(struct generic_pm_domain *domain)
{
	return exynos_pd_power(domain, true);
}

static int exynos_pd_power_off(struct generic_pm_domain *domain)
{
	return exynos_pd_power(domain, false);
}

static void exynos_add_device_to_domain(struct exynos_pm_domain *pd,
					 struct device *dev)
{
	int ret;

	dev_dbg(dev, "adding to power domain %s\n", pd->pd.name);

	while (1) {
		ret = pm_genpd_add_device(&pd->pd, dev);
		if (ret != -EAGAIN)
			break;
		cond_resched();
	}

	pm_genpd_dev_need_restore(dev, true);
}

static void exynos_remove_device_from_domain(struct device *dev)
{
	struct generic_pm_domain *genpd = dev_to_genpd(dev);
	int ret;

	dev_dbg(dev, "removing from power domain %s\n", genpd->name);

	while (1) {
		ret = pm_genpd_remove_device(genpd, dev);
		if (ret != -EAGAIN)
			break;
		cond_resched();
	}
}

static void exynos_read_domain_from_dt(struct device *dev)
{
	struct platform_device *pd_pdev;
	struct exynos_pm_domain *pd;
	struct device_node *node;

	node = of_parse_phandle(dev->of_node, "samsung,power-domain", 0);
	if (!node)
		return;
	pd_pdev = of_find_device_by_node(node);
	if (!pd_pdev)
		return;
	pd = platform_get_drvdata(pd_pdev);
	exynos_add_device_to_domain(pd, dev);
}

static int exynos_pm_notifier_call(struct notifier_block *nb,
				    unsigned long event, void *data)
{
	struct device *dev = data;

	switch (event) {
	case BUS_NOTIFY_BIND_DRIVER:
		if (dev->of_node)
			exynos_read_domain_from_dt(dev);

		break;

	case BUS_NOTIFY_UNBOUND_DRIVER:
		exynos_remove_device_from_domain(dev);

		break;
	}
	return NOTIFY_DONE;
}

static struct notifier_block platform_nb = {
	.notifier_call = exynos_pm_notifier_call,
};

static __init int exynos4_pm_init_power_domain(void)
{
	struct platform_device *pdev;
	struct device_node *np;

	for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") {
		struct exynos_pm_domain *pd;
		int on, i;
		struct device *dev;

		pdev = of_find_device_by_node(np);
		dev = &pdev->dev;

		pd = kzalloc(sizeof(*pd), GFP_KERNEL);
		if (!pd) {
			pr_err("%s: failed to allocate memory for domain\n",
					__func__);
			return -ENOMEM;
		}

		pd->pd.name = kstrdup(np->name, GFP_KERNEL);
		pd->name = pd->pd.name;
		pd->base = of_iomap(np, 0);
		pd->pd.power_off = exynos_pd_power_off;
		pd->pd.power_on = exynos_pd_power_on;
		pd->pd.of_node = np;

		pd->oscclk = clk_get(dev, "oscclk");
		if (IS_ERR(pd->oscclk))
			goto no_clk;

		for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
			char clk_name[8];

			snprintf(clk_name, sizeof(clk_name), "clk%d", i);
			pd->clk[i] = clk_get(dev, clk_name);
			if (IS_ERR(pd->clk[i]))
				break;
			snprintf(clk_name, sizeof(clk_name), "pclk%d", i);
			pd->pclk[i] = clk_get(dev, clk_name);
			if (IS_ERR(pd->pclk[i])) {
				clk_put(pd->clk[i]);
				pd->clk[i] = ERR_PTR(-EINVAL);
				break;
			}
		}

		if (IS_ERR(pd->clk[0]))
			clk_put(pd->oscclk);

no_clk:
		platform_set_drvdata(pdev, pd);

		on = __raw_readl(pd->base + 0x4) & INT_LOCAL_PWR_EN;

		pm_genpd_init(&pd->pd, NULL, !on);
	}

	bus_register_notifier(&platform_bus_type, &platform_nb);

	return 0;
}
arch_initcall(exynos4_pm_init_power_domain);
Commit	Line	Data
91cfbd4e TA	1	/*
	2	* Exynos Generic power domain support.
	3	*
	4	* Copyright (c) 2012 Samsung Electronics Co., Ltd.
	5	* http://www.samsung.com
	6	*
	7	* Implementation of Exynos specific power domain control which is used in
	8	* conjunction with runtime-pm. Support for both device-tree and non-device-tree
	9	* based power domain support is included.
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2 as
	13	* published by the Free Software Foundation.
	14	*/
	15
	16	#include <linux/io.h>
	17	#include <linux/err.h>
	18	#include <linux/slab.h>
	19	#include <linux/pm_domain.h>
c760569d	20	#include <linux/clk.h>
91cfbd4e TA	21	#include <linux/delay.h>
91cfbd4e TA	22	#include <linux/of_address.h>
8a65d236 TF	23	#include <linux/of_platform.h>
8a65d236 TF	24	#include <linux/sched.h>
91cfbd4e	25
b634e38f	26	#define INT_LOCAL_PWR_EN 0x7
c760569d P	27	#define MAX_CLK_PER_DOMAIN 4
c760569d P	28
91cfbd4e TA	29	/*
	30	* Exynos specific wrapper around the generic power domain
	31	*/
	32	struct exynos_pm_domain {
	33	void __iomem *base;
	34	char const *name;
	35	bool is_off;
	36	struct generic_pm_domain pd;
c760569d P	37	struct clk *oscclk;
	38	struct clk *clk[MAX_CLK_PER_DOMAIN];
	39	struct clk *pclk[MAX_CLK_PER_DOMAIN];
91cfbd4e TA	40	};
	41
	42	static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
	43	{
	44	struct exynos_pm_domain *pd;
	45	void __iomem *base;
	46	u32 timeout, pwr;
	47	char *op;
	48
	49	pd = container_of(domain, struct exynos_pm_domain, pd);
	50	base = pd->base;
	51
c760569d P	52	/* Set oscclk before powering off a domain*/
	53	if (!power_on) {
	54	int i;
	55
	56	for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
	57	if (IS_ERR(pd->clk[i]))
	58	break;
	59	if (clk_set_parent(pd->clk[i], pd->oscclk))
	60	pr_err("%s: error setting oscclk as parent to clock %d\n",
	61	pd->name, i);
	62	}
	63	}
	64
b634e38f	65	pwr = power_on ? INT_LOCAL_PWR_EN : 0;
91cfbd4e TA	66	__raw_writel(pwr, base);
	67
	68	/* Wait max 1ms */
	69	timeout = 10;
	70
b634e38f	71	while ((__raw_readl(base + 0x4) & INT_LOCAL_PWR_EN) != pwr) {
91cfbd4e TA	72	if (!timeout) {
	73	op = (power_on) ? "enable" : "disable";
	74	pr_err("Power domain %s %s failed\n", domain->name, op);
	75	return -ETIMEDOUT;
	76	}
	77	timeout--;
	78	cpu_relax();
	79	usleep_range(80, 100);
	80	}
c760569d P	81
	82	/* Restore clocks after powering on a domain*/
	83	if (power_on) {
	84	int i;
	85
	86	for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
	87	if (IS_ERR(pd->clk[i]))
	88	break;
	89	if (clk_set_parent(pd->clk[i], pd->pclk[i]))
	90	pr_err("%s: error setting parent to clock%d\n",
	91	pd->name, i);
	92	}
	93	}
	94
91cfbd4e TA	95	return 0;
	96	}
	97
	98	static int exynos_pd_power_on(struct generic_pm_domain *domain)
	99	{
	100	return exynos_pd_power(domain, true);
	101	}
	102
	103	static int exynos_pd_power_off(struct generic_pm_domain *domain)
	104	{
	105	return exynos_pd_power(domain, false);
	106	}
	107
8a65d236 TF	108	static void exynos_add_device_to_domain(struct exynos_pm_domain *pd,
	109	struct device *dev)
	110	{
	111	int ret;
	112
	113	dev_dbg(dev, "adding to power domain %s\n", pd->pd.name);
	114
	115	while (1) {
	116	ret = pm_genpd_add_device(&pd->pd, dev);
	117	if (ret != -EAGAIN)
	118	break;
	119	cond_resched();
	120	}
	121
	122	pm_genpd_dev_need_restore(dev, true);
	123	}
	124
	125	static void exynos_remove_device_from_domain(struct device *dev)
	126	{
	127	struct generic_pm_domain *genpd = dev_to_genpd(dev);
	128	int ret;
	129
	130	dev_dbg(dev, "removing from power domain %s\n", genpd->name);
	131
	132	while (1) {
	133	ret = pm_genpd_remove_device(genpd, dev);
	134	if (ret != -EAGAIN)
	135	break;
	136	cond_resched();
	137	}
	138	}
	139
	140	static void exynos_read_domain_from_dt(struct device *dev)
	141	{
	142	struct platform_device *pd_pdev;
	143	struct exynos_pm_domain *pd;
	144	struct device_node *node;
	145
	146	node = of_parse_phandle(dev->of_node, "samsung,power-domain", 0);
	147	if (!node)
	148	return;
	149	pd_pdev = of_find_device_by_node(node);
	150	if (!pd_pdev)
	151	return;
	152	pd = platform_get_drvdata(pd_pdev);
	153	exynos_add_device_to_domain(pd, dev);
	154	}
	155
	156	static int exynos_pm_notifier_call(struct notifier_block *nb,
	157	unsigned long event, void *data)
	158	{
	159	struct device *dev = data;
	160
	161	switch (event) {
	162	case BUS_NOTIFY_BIND_DRIVER:
	163	if (dev->of_node)
	164	exynos_read_domain_from_dt(dev);
	165
	166	break;
	167
	168	case BUS_NOTIFY_UNBOUND_DRIVER:
	169	exynos_remove_device_from_domain(dev);
	170
	171	break;
172	}
173	return NOTIFY_DONE;
174	}
175
176	static struct notifier_block platform_nb = {
177	.notifier_call = exynos_pm_notifier_call,
178	};
179
8eaa9e42	180	static __init int exynos4_pm_init_power_domain(void)
91cfbd4e	181	{
8a65d236	182	struct platform_device *pdev;
91cfbd4e TA	183	struct device_node *np;
	184
	185	for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") {
	186	struct exynos_pm_domain *pd;
c760569d P	187	int on, i;
c760569d P	188	struct device *dev;
91cfbd4e	189
8a65d236	190	pdev = of_find_device_by_node(np);
c760569d	191	dev = &pdev->dev;
8a65d236	192
91cfbd4e TA	193	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
	194	if (!pd) {
	195	pr_err("%s: failed to allocate memory for domain\n",
	196	__func__);
	197	return -ENOMEM;
	198	}
	199
7add0ec0 TF	200	pd->pd.name = kstrdup(np->name, GFP_KERNEL);
7add0ec0 TF	201	pd->name = pd->pd.name;
91cfbd4e TA	202	pd->base = of_iomap(np, 0);
	203	pd->pd.power_off = exynos_pd_power_off;
	204	pd->pd.power_on = exynos_pd_power_on;
	205	pd->pd.of_node = np;
2ed5f236	206
c760569d P	207	pd->oscclk = clk_get(dev, "oscclk");
	208	if (IS_ERR(pd->oscclk))
	209	goto no_clk;
	210
	211	for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
	212	char clk_name[8];
	213
	214	snprintf(clk_name, sizeof(clk_name), "clk%d", i);
	215	pd->clk[i] = clk_get(dev, clk_name);
	216	if (IS_ERR(pd->clk[i]))
	217	break;
	218	snprintf(clk_name, sizeof(clk_name), "pclk%d", i);
	219	pd->pclk[i] = clk_get(dev, clk_name);
	220	if (IS_ERR(pd->pclk[i])) {
	221	clk_put(pd->clk[i]);
	222	pd->clk[i] = ERR_PTR(-EINVAL);
	223	break;
	224	}
	225	}
	226
	227	if (IS_ERR(pd->clk[0]))
	228	clk_put(pd->oscclk);
	229
	230	no_clk:
8a65d236 TF	231	platform_set_drvdata(pdev, pd);
8a65d236 TF	232
b634e38f	233	on = __raw_readl(pd->base + 0x4) & INT_LOCAL_PWR_EN;
2ed5f236 TF	234
2ed5f236 TF	235	pm_genpd_init(&pd->pd, NULL, !on);
91cfbd4e	236	}
8a65d236 TF	237
	238	bus_register_notifier(&platform_bus_type, &platform_nb);
	239
91cfbd4e TA	240	return 0;
91cfbd4e TA	241	}
91cfbd4e	242	arch_initcall(exynos4_pm_init_power_domain);