[linux-2.6-block.git] / drivers / misc / vexpress-syscfg.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * Copyright (C) 2014 ARM Limited
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/syscore_ops.h>
#include <linux/vexpress.h>


#define SYS_CFGDATA		0x0

#define SYS_CFGCTRL		0x4
#define SYS_CFGCTRL_START	(1 << 31)
#define SYS_CFGCTRL_WRITE	(1 << 30)
#define SYS_CFGCTRL_DCC(n)	(((n) & 0xf) << 26)
#define SYS_CFGCTRL_FUNC(n)	(((n) & 0x3f) << 20)
#define SYS_CFGCTRL_SITE(n)	(((n) & 0x3) << 16)
#define SYS_CFGCTRL_POSITION(n)	(((n) & 0xf) << 12)
#define SYS_CFGCTRL_DEVICE(n)	(((n) & 0xfff) << 0)

#define SYS_CFGSTAT		0x8
#define SYS_CFGSTAT_ERR		(1 << 1)
#define SYS_CFGSTAT_COMPLETE	(1 << 0)


struct vexpress_syscfg {
	struct device *dev;
	void __iomem *base;
	struct list_head funcs;
};

struct vexpress_syscfg_func {
	struct list_head list;
	struct vexpress_syscfg *syscfg;
	struct regmap *regmap;
	int num_templates;
	u32 template[0]; /* Keep it last! */
};


static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
		int index, bool write, u32 *data)
{
	struct vexpress_syscfg *syscfg = func->syscfg;
	u32 command, status;
	int tries;
	long timeout;

	if (WARN_ON(index >= func->num_templates))
		return -EINVAL;

	command = readl(syscfg->base + SYS_CFGCTRL);
	if (WARN_ON(command & SYS_CFGCTRL_START))
		return -EBUSY;

	command = func->template[index];
	command |= SYS_CFGCTRL_START;
	command |= write ? SYS_CFGCTRL_WRITE : 0;

	/* Use a canary for reads */
	if (!write)
		*data = 0xdeadbeef;

	dev_dbg(syscfg->dev, "func %p, command %x, data %x\n",
			func, command, *data);
	writel(*data, syscfg->base + SYS_CFGDATA);
	writel(0, syscfg->base + SYS_CFGSTAT);
	writel(command, syscfg->base + SYS_CFGCTRL);
	mb();

	/* The operation can take ages... Go to sleep, 100us initially */
	tries = 100;
	timeout = 100;
	do {
		if (!irqs_disabled()) {
			set_current_state(TASK_INTERRUPTIBLE);
			schedule_timeout(usecs_to_jiffies(timeout));
			if (signal_pending(current))
				return -EINTR;
		} else {
			udelay(timeout);
		}

		status = readl(syscfg->base + SYS_CFGSTAT);
		if (status & SYS_CFGSTAT_ERR)
			return -EFAULT;

		if (timeout > 20)
			timeout -= 20;
	} while (--tries && !(status & SYS_CFGSTAT_COMPLETE));
	if (WARN_ON_ONCE(!tries))
		return -ETIMEDOUT;

	if (!write) {
		*data = readl(syscfg->base + SYS_CFGDATA);
		dev_dbg(syscfg->dev, "func %p, read data %x\n", func, *data);
	}

	return 0;
}

static int vexpress_syscfg_read(void *context, unsigned int index,
		unsigned int *val)
{
	struct vexpress_syscfg_func *func = context;

	return vexpress_syscfg_exec(func, index, false, val);
}

static int vexpress_syscfg_write(void *context, unsigned int index,
		unsigned int val)
{
	struct vexpress_syscfg_func *func = context;

	return vexpress_syscfg_exec(func, index, true, &val);
}

static struct regmap_config vexpress_syscfg_regmap_config = {
	.lock = vexpress_config_lock,
	.unlock = vexpress_config_unlock,
	.reg_bits = 32,
	.val_bits = 32,
	.reg_read = vexpress_syscfg_read,
	.reg_write = vexpress_syscfg_write,
	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
	.val_format_endian = REGMAP_ENDIAN_LITTLE,
};


static struct regmap *vexpress_syscfg_regmap_init(struct device *dev,
		void *context)
{
	int err;
	struct vexpress_syscfg *syscfg = context;
	struct vexpress_syscfg_func *func;
	struct property *prop;
	const __be32 *val = NULL;
	__be32 energy_quirk[4];
	int num;
	u32 site, position, dcc;
	int i;

	err = vexpress_config_get_topo(dev->of_node, &site,
				&position, &dcc);
	if (err)
		return ERR_PTR(err);

	prop = of_find_property(dev->of_node,
			"arm,vexpress-sysreg,func", NULL);
	if (!prop)
		return ERR_PTR(-EINVAL);

	num = prop->length / sizeof(u32) / 2;
	val = prop->value;

	/*
	 * "arm,vexpress-energy" function used to be described
	 * by its first device only, now it requires both
	 */
	if (num == 1 && of_device_is_compatible(dev->of_node,
			"arm,vexpress-energy")) {
		num = 2;
		energy_quirk[0] = *val;
		energy_quirk[2] = *val++;
		energy_quirk[1] = *val;
		energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
		val = energy_quirk;
	}

	func = kzalloc(struct_size(func, template, num), GFP_KERNEL);
	if (!func)
		return ERR_PTR(-ENOMEM);

	func->syscfg = syscfg;
	func->num_templates = num;

	for (i = 0; i < num; i++) {
		u32 function, device;

		function = be32_to_cpup(val++);
		device = be32_to_cpup(val++);

		dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
				func, site, position, dcc,
				function, device);

		func->template[i] = SYS_CFGCTRL_DCC(dcc);
		func->template[i] |= SYS_CFGCTRL_SITE(site);
		func->template[i] |= SYS_CFGCTRL_POSITION(position);
		func->template[i] |= SYS_CFGCTRL_FUNC(function);
		func->template[i] |= SYS_CFGCTRL_DEVICE(device);
	}

	vexpress_syscfg_regmap_config.max_register = num - 1;

	func->regmap = regmap_init(dev, NULL, func,
			&vexpress_syscfg_regmap_config);

	if (IS_ERR(func->regmap)) {
		void *err = func->regmap;

		kfree(func);
		return err;
	}

	list_add(&func->list, &syscfg->funcs);

	return func->regmap;
}

static void vexpress_syscfg_regmap_exit(struct regmap *regmap, void *context)
{
	struct vexpress_syscfg *syscfg = context;
	struct vexpress_syscfg_func *func, *tmp;

	regmap_exit(regmap);

	list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
		if (func->regmap == regmap) {
			list_del(&syscfg->funcs);
			kfree(func);
			break;
		}
	}
}

static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
	.regmap_init = vexpress_syscfg_regmap_init,
	.regmap_exit = vexpress_syscfg_regmap_exit,
};


static int vexpress_syscfg_probe(struct platform_device *pdev)
{
	struct vexpress_syscfg *syscfg;
	struct resource *res;
	struct device *bridge;

	syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
	if (!syscfg)
		return -ENOMEM;
	syscfg->dev = &pdev->dev;
	INIT_LIST_HEAD(&syscfg->funcs);

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

	/* Must use dev.parent (MFD), as that's where DT phandle points at... */
	bridge = vexpress_config_bridge_register(pdev->dev.parent,
			&vexpress_syscfg_bridge_ops, syscfg);

	return PTR_ERR_OR_ZERO(bridge);
}

static const struct platform_device_id vexpress_syscfg_id_table[] = {
	{ "vexpress-syscfg", },
	{},
};

static struct platform_driver vexpress_syscfg_driver = {
	.driver.name = "vexpress-syscfg",
	.id_table = vexpress_syscfg_id_table,
	.probe = vexpress_syscfg_probe,
};

static int __init vexpress_syscfg_init(void)
{
	return platform_driver_register(&vexpress_syscfg_driver);
}
core_initcall(vexpress_syscfg_init);
Commit	Line	Data
1802d0be	1	// SPDX-License-Identifier: GPL-2.0-only
974cc7b9	2	/*
974cc7b9 PM	3	*
	4	* Copyright (C) 2014 ARM Limited
	5	*/
	6
	7	#include <linux/delay.h>
	8	#include <linux/err.h>
	9	#include <linux/io.h>
	10	#include <linux/of.h>
	11	#include <linux/platform_device.h>
174cd4b1	12	#include <linux/sched/signal.h>
974cc7b9 PM	13	#include <linux/slab.h>
	14	#include <linux/syscore_ops.h>
	15	#include <linux/vexpress.h>
	16
	17
	18	#define SYS_CFGDATA 0x0
	19
	20	#define SYS_CFGCTRL 0x4
	21	#define SYS_CFGCTRL_START (1 << 31)
	22	#define SYS_CFGCTRL_WRITE (1 << 30)
	23	#define SYS_CFGCTRL_DCC(n) (((n) & 0xf) << 26)
	24	#define SYS_CFGCTRL_FUNC(n) (((n) & 0x3f) << 20)
	25	#define SYS_CFGCTRL_SITE(n) (((n) & 0x3) << 16)
	26	#define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
	27	#define SYS_CFGCTRL_DEVICE(n) (((n) & 0xfff) << 0)
	28
	29	#define SYS_CFGSTAT 0x8
	30	#define SYS_CFGSTAT_ERR (1 << 1)
	31	#define SYS_CFGSTAT_COMPLETE (1 << 0)
	32
	33
	34	struct vexpress_syscfg {
	35	struct device *dev;
	36	void __iomem *base;
	37	struct list_head funcs;
	38	};
	39
	40	struct vexpress_syscfg_func {
	41	struct list_head list;
	42	struct vexpress_syscfg *syscfg;
	43	struct regmap *regmap;
	44	int num_templates;
	45	u32 template[0]; /* Keep it last! */
	46	};
	47
	48
	49	static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
	50	int index, bool write, u32 *data)
	51	{
	52	struct vexpress_syscfg *syscfg = func->syscfg;
	53	u32 command, status;
	54	int tries;
	55	long timeout;
	56
f8a70d8b	57	if (WARN_ON(index >= func->num_templates))
974cc7b9 PM	58	return -EINVAL;
	59
	60	command = readl(syscfg->base + SYS_CFGCTRL);
	61	if (WARN_ON(command & SYS_CFGCTRL_START))
	62	return -EBUSY;
	63
	64	command = func->template[index];
	65	command \|= SYS_CFGCTRL_START;
	66	command \|= write ? SYS_CFGCTRL_WRITE : 0;
	67
	68	/* Use a canary for reads */
	69	if (!write)
	70	*data = 0xdeadbeef;
	71
	72	dev_dbg(syscfg->dev, "func %p, command %x, data %x\n",
	73	func, command, *data);
	74	writel(*data, syscfg->base + SYS_CFGDATA);
	75	writel(0, syscfg->base + SYS_CFGSTAT);
	76	writel(command, syscfg->base + SYS_CFGCTRL);
	77	mb();
	78
	79	/* The operation can take ages... Go to sleep, 100us initially */
	80	tries = 100;
	81	timeout = 100;
	82	do {
	83	if (!irqs_disabled()) {
	84	set_current_state(TASK_INTERRUPTIBLE);
	85	schedule_timeout(usecs_to_jiffies(timeout));
	86	if (signal_pending(current))
	87	return -EINTR;
	88	} else {
	89	udelay(timeout);
	90	}
	91
	92	status = readl(syscfg->base + SYS_CFGSTAT);
	93	if (status & SYS_CFGSTAT_ERR)
	94	return -EFAULT;
	95
	96	if (timeout > 20)
	97	timeout -= 20;
	98	} while (--tries && !(status & SYS_CFGSTAT_COMPLETE));
	99	if (WARN_ON_ONCE(!tries))
	100	return -ETIMEDOUT;
	101
	102	if (!write) {
	103	*data = readl(syscfg->base + SYS_CFGDATA);
	104	dev_dbg(syscfg->dev, "func %p, read data %x\n", func, *data);
	105	}
	106
	107	return 0;
	108	}
	109
	110	static int vexpress_syscfg_read(void *context, unsigned int index,
	111	unsigned int *val)
	112	{
	113	struct vexpress_syscfg_func *func = context;
	114
	115	return vexpress_syscfg_exec(func, index, false, val);
	116	}
	117
	118	static int vexpress_syscfg_write(void *context, unsigned int index,
	119	unsigned int val)
	120	{
	121	struct vexpress_syscfg_func *func = context;
122
123	return vexpress_syscfg_exec(func, index, true, &val);
124	}
125
f222447e	126	static struct regmap_config vexpress_syscfg_regmap_config = {
974cc7b9 PM	127	.lock = vexpress_config_lock,
	128	.unlock = vexpress_config_unlock,
	129	.reg_bits = 32,
	130	.val_bits = 32,
	131	.reg_read = vexpress_syscfg_read,
	132	.reg_write = vexpress_syscfg_write,
	133	.reg_format_endian = REGMAP_ENDIAN_LITTLE,
	134	.val_format_endian = REGMAP_ENDIAN_LITTLE,
	135	};
	136
	137
	138	static struct regmap vexpress_syscfg_regmap_init(struct device dev,
	139	void *context)
	140	{
81cc3f86	141	int err;
974cc7b9 PM	142	struct vexpress_syscfg *syscfg = context;
	143	struct vexpress_syscfg_func *func;
	144	struct property *prop;
	145	const __be32 *val = NULL;
	146	__be32 energy_quirk[4];
	147	int num;
	148	u32 site, position, dcc;
	149	int i;
	150
81cc3f86	151	err = vexpress_config_get_topo(dev->of_node, &site,
974cc7b9	152	&position, &dcc);
81cc3f86 PM	153	if (err)
81cc3f86 PM	154	return ERR_PTR(err);
974cc7b9	155
81cc3f86 PM	156	prop = of_find_property(dev->of_node,
	157	"arm,vexpress-sysreg,func", NULL);
	158	if (!prop)
	159	return ERR_PTR(-EINVAL);
	160
	161	num = prop->length / sizeof(u32) / 2;
	162	val = prop->value;
974cc7b9 PM	163
	164	/*
	165	* "arm,vexpress-energy" function used to be described
	166	* by its first device only, now it requires both
	167	*/
	168	if (num == 1 && of_device_is_compatible(dev->of_node,
	169	"arm,vexpress-energy")) {
	170	num = 2;
	171	energy_quirk[0] = *val;
	172	energy_quirk[2] = *val++;
	173	energy_quirk[1] = *val;
	174	energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
	175	val = energy_quirk;
	176	}
	177
acafe7e3	178	func = kzalloc(struct_size(func, template, num), GFP_KERNEL);
974cc7b9	179	if (!func)
b86e1926	180	return ERR_PTR(-ENOMEM);
974cc7b9 PM	181
	182	func->syscfg = syscfg;
	183	func->num_templates = num;
	184
	185	for (i = 0; i < num; i++) {
	186	u32 function, device;
	187
81cc3f86 PM	188	function = be32_to_cpup(val++);
81cc3f86 PM	189	device = be32_to_cpup(val++);
974cc7b9 PM	190
	191	dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
	192	func, site, position, dcc,
	193	function, device);
	194
	195	func->template[i] = SYS_CFGCTRL_DCC(dcc);
	196	func->template[i] \|= SYS_CFGCTRL_SITE(site);
	197	func->template[i] \|= SYS_CFGCTRL_POSITION(position);
	198	func->template[i] \|= SYS_CFGCTRL_FUNC(function);
	199	func->template[i] \|= SYS_CFGCTRL_DEVICE(device);
	200	}
	201
	202	vexpress_syscfg_regmap_config.max_register = num - 1;
	203
	204	func->regmap = regmap_init(dev, NULL, func,
	205	&vexpress_syscfg_regmap_config);
	206
b86e1926 DC	207	if (IS_ERR(func->regmap)) {
	208	void *err = func->regmap;
	209
974cc7b9	210	kfree(func);
b86e1926 DC	211	return err;
	212	}
	213
	214	list_add(&func->list, &syscfg->funcs);
974cc7b9 PM	215
	216	return func->regmap;
	217	}
	218
	219	static void vexpress_syscfg_regmap_exit(struct regmap regmap, void context)
	220	{
	221	struct vexpress_syscfg *syscfg = context;
	222	struct vexpress_syscfg_func func, tmp;
	223
	224	regmap_exit(regmap);
	225
	226	list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
	227	if (func->regmap == regmap) {
	228	list_del(&syscfg->funcs);
	229	kfree(func);
	230	break;
	231	}
	232	}
	233	}
	234
	235	static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
	236	.regmap_init = vexpress_syscfg_regmap_init,
	237	.regmap_exit = vexpress_syscfg_regmap_exit,
	238	};
	239
	240
f222447e	241	static int vexpress_syscfg_probe(struct platform_device *pdev)
974cc7b9 PM	242	{
	243	struct vexpress_syscfg *syscfg;
	244	struct resource *res;
	245	struct device *bridge;
	246
	247	syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
	248	if (!syscfg)
	249	return -ENOMEM;
	250	syscfg->dev = &pdev->dev;
	251	INIT_LIST_HEAD(&syscfg->funcs);
	252
	253	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
555e7943 SH	254	syscfg->base = devm_ioremap_resource(&pdev->dev, res);
	255	if (IS_ERR(syscfg->base))
	256	return PTR_ERR(syscfg->base);
974cc7b9 PM	257
	258	/* Must use dev.parent (MFD), as that's where DT phandle points at... */
	259	bridge = vexpress_config_bridge_register(pdev->dev.parent,
	260	&vexpress_syscfg_bridge_ops, syscfg);
974cc7b9	261
eecf4f9d	262	return PTR_ERR_OR_ZERO(bridge);
974cc7b9 PM	263	}
	264
	265	static const struct platform_device_id vexpress_syscfg_id_table[] = {
	266	{ "vexpress-syscfg", },
	267	{},
	268	};
	269
	270	static struct platform_driver vexpress_syscfg_driver = {
	271	.driver.name = "vexpress-syscfg",
	272	.id_table = vexpress_syscfg_id_table,
	273	.probe = vexpress_syscfg_probe,
	274	};
	275
	276	static int __init vexpress_syscfg_init(void)
	277	{
	278	return platform_driver_register(&vexpress_syscfg_driver);
	279	}
	280	core_initcall(vexpress_syscfg_init);