[mirror_ubuntu-zesty-kernel.git] / drivers / of / of_reserved_mem.c

/*
 * Device tree based initialization code for reserved memory.
 *
 * Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
 * Copyright (c) 2013,2014 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com
 * Author: Marek Szyprowski <m.szyprowski@samsung.com>
 * Author: Josh Cartwright <joshc@codeaurora.org>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License or (at your optional) any later version of the license.
 */

#define pr_fmt(fmt)	"OF: reserved mem: " fmt

#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/mm.h>
#include <linux/sizes.h>
#include <linux/of_reserved_mem.h>
#include <linux/sort.h>
#include <linux/slab.h>

#define MAX_RESERVED_REGIONS	16
static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
static int reserved_mem_count;

#if defined(CONFIG_HAVE_MEMBLOCK)
#include <linux/memblock.h>
int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
	phys_addr_t *res_base)
{
	phys_addr_t base;
	/*
	 * We use __memblock_alloc_base() because memblock_alloc_base()
	 * panic()s on allocation failure.
	 */
	end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
	base = __memblock_alloc_base(size, align, end);
	if (!base)
		return -ENOMEM;

	/*
	 * Check if the allocated region fits in to start..end window
	 */
	if (base < start) {
		memblock_free(base, size);
		return -ENOMEM;
	}

	*res_base = base;
	if (nomap)
		return memblock_remove(base, size);
	return 0;
}
#else
int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
	phys_addr_t *res_base)
{
	pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
		  size, nomap ? " (nomap)" : "");
	return -ENOSYS;
}
#endif

/**
 * res_mem_save_node() - save fdt node for second pass initialization
 */
void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
				      phys_addr_t base, phys_addr_t size)
{
	struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];

	if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
		pr_err("not enough space all defined regions.\n");
		return;
	}

	rmem->fdt_node = node;
	rmem->name = uname;
	rmem->base = base;
	rmem->size = size;

	reserved_mem_count++;
	return;
}

/**
 * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
 *			  and 'alloc-ranges' properties
 */
static int __init __reserved_mem_alloc_size(unsigned long node,
	const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
{
	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
	phys_addr_t start = 0, end = 0;
	phys_addr_t base = 0, align = 0, size;
	int len;
	const __be32 *prop;
	int nomap;
	int ret;

	prop = of_get_flat_dt_prop(node, "size", &len);
	if (!prop)
		return -EINVAL;

	if (len != dt_root_size_cells * sizeof(__be32)) {
		pr_err("invalid size property in '%s' node.\n", uname);
		return -EINVAL;
	}
	size = dt_mem_next_cell(dt_root_size_cells, &prop);

	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;

	prop = of_get_flat_dt_prop(node, "alignment", &len);
	if (prop) {
		if (len != dt_root_addr_cells * sizeof(__be32)) {
			pr_err("invalid alignment property in '%s' node.\n",
				uname);
			return -EINVAL;
		}
		align = dt_mem_next_cell(dt_root_addr_cells, &prop);
	}

	/* Need adjust the alignment to satisfy the CMA requirement */
	if (IS_ENABLED(CONFIG_CMA)
	    && of_flat_dt_is_compatible(node, "shared-dma-pool")
	    && of_get_flat_dt_prop(node, "reusable", NULL)
	    && !of_get_flat_dt_prop(node, "no-map", NULL)) {
		unsigned long order =
			max_t(unsigned long, MAX_ORDER - 1, pageblock_order);

		align = max(align, (phys_addr_t)PAGE_SIZE << order);
	}

	prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
	if (prop) {

		if (len % t_len != 0) {
			pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
			       uname);
			return -EINVAL;
		}

		base = 0;

		while (len > 0) {
			start = dt_mem_next_cell(dt_root_addr_cells, &prop);
			end = start + dt_mem_next_cell(dt_root_size_cells,
						       &prop);

			ret = early_init_dt_alloc_reserved_memory_arch(size,
					align, start, end, nomap, &base);
			if (ret == 0) {
				pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
					uname, &base,
					(unsigned long)size / SZ_1M);
				break;
			}
			len -= t_len;
		}

	} else {
		ret = early_init_dt_alloc_reserved_memory_arch(size, align,
							0, 0, nomap, &base);
		if (ret == 0)
			pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
				uname, &base, (unsigned long)size / SZ_1M);
	}

	if (base == 0) {
		pr_info("failed to allocate memory for node '%s'\n", uname);
		return -ENOMEM;
	}

	*res_base = base;
	*res_size = size;

	return 0;
}

static const struct of_device_id __rmem_of_table_sentinel
	__used __section(__reservedmem_of_table_end);

/**
 * res_mem_init_node() - call region specific reserved memory init code
 */
static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
{
	extern const struct of_device_id __reservedmem_of_table[];
	const struct of_device_id *i;

	for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
		reservedmem_of_init_fn initfn = i->data;
		const char *compat = i->compatible;

		if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
			continue;

		if (initfn(rmem) == 0) {
			pr_info("initialized node %s, compatible id %s\n",
				rmem->name, compat);
			return 0;
		}
	}
	return -ENOENT;
}

static int __init __rmem_cmp(const void *a, const void *b)
{
	const struct reserved_mem *ra = a, *rb = b;

	if (ra->base < rb->base)
		return -1;

	if (ra->base > rb->base)
		return 1;

	return 0;
}

static void __init __rmem_check_for_overlap(void)
{
	int i;

	if (reserved_mem_count < 2)
		return;

	sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
	     __rmem_cmp, NULL);
	for (i = 0; i < reserved_mem_count - 1; i++) {
		struct reserved_mem *this, *next;

		this = &reserved_mem[i];
		next = &reserved_mem[i + 1];
		if (!(this->base && next->base))
			continue;
		if (this->base + this->size > next->base) {
			phys_addr_t this_end, next_end;

			this_end = this->base + this->size;
			next_end = next->base + next->size;
			pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
			       this->name, &this->base, &this_end,
			       next->name, &next->base, &next_end);
		}
	}
}

/**
 * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
 */
void __init fdt_init_reserved_mem(void)
{
	int i;

	/* check for overlapping reserved regions */
	__rmem_check_for_overlap();

	for (i = 0; i < reserved_mem_count; i++) {
		struct reserved_mem *rmem = &reserved_mem[i];
		unsigned long node = rmem->fdt_node;
		int len;
		const __be32 *prop;
		int err = 0;

		prop = of_get_flat_dt_prop(node, "phandle", &len);
		if (!prop)
			prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
		if (prop)
			rmem->phandle = of_read_number(prop, len/4);

		if (rmem->size == 0)
			err = __reserved_mem_alloc_size(node, rmem->name,
						 &rmem->base, &rmem->size);
		if (err == 0)
			__reserved_mem_init_node(rmem);
	}
}

static inline struct reserved_mem *__find_rmem(struct device_node *node)
{
	unsigned int i;

	if (!node->phandle)
		return NULL;

	for (i = 0; i < reserved_mem_count; i++)
		if (reserved_mem[i].phandle == node->phandle)
			return &reserved_mem[i];
	return NULL;
}

struct rmem_assigned_device {
	struct device *dev;
	struct reserved_mem *rmem;
	struct list_head list;
};

static LIST_HEAD(of_rmem_assigned_device_list);
static DEFINE_MUTEX(of_rmem_assigned_device_mutex);

/**
 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
 *					  given device
 * @dev:	Pointer to the device to configure
 * @np:		Pointer to the device_node with 'reserved-memory' property
 * @idx:	Index of selected region
 *
 * This function assigns respective DMA-mapping operations based on reserved
 * memory region specified by 'memory-region' property in @np node to the @dev
 * device. When driver needs to use more than one reserved memory region, it
 * should allocate child devices and initialize regions by name for each of
 * child device.
 *
 * Returns error code or zero on success.
 */
int of_reserved_mem_device_init_by_idx(struct device *dev,
				       struct device_node *np, int idx)
{
	struct rmem_assigned_device *rd;
	struct device_node *target;
	struct reserved_mem *rmem;
	int ret;

	if (!np || !dev)
		return -EINVAL;

	target = of_parse_phandle(np, "memory-region", idx);
	if (!target)
		return -ENODEV;

	rmem = __find_rmem(target);
	of_node_put(target);

	if (!rmem || !rmem->ops || !rmem->ops->device_init)
		return -EINVAL;

	rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
	if (!rd)
		return -ENOMEM;

	ret = rmem->ops->device_init(rmem, dev);
	if (ret == 0) {
		rd->dev = dev;
		rd->rmem = rmem;

		mutex_lock(&of_rmem_assigned_device_mutex);
		list_add(&rd->list, &of_rmem_assigned_device_list);
		mutex_unlock(&of_rmem_assigned_device_mutex);

		dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
	} else {
		kfree(rd);
	}

	return ret;
}
EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);

/**
 * of_reserved_mem_device_release() - release reserved memory device structures
 * @dev:	Pointer to the device to deconfigure
 *
 * This function releases structures allocated for memory region handling for
 * the given device.
 */
void of_reserved_mem_device_release(struct device *dev)
{
	struct rmem_assigned_device *rd;
	struct reserved_mem *rmem = NULL;

	mutex_lock(&of_rmem_assigned_device_mutex);
	list_for_each_entry(rd, &of_rmem_assigned_device_list, list) {
		if (rd->dev == dev) {
			rmem = rd->rmem;
			list_del(&rd->list);
			kfree(rd);
			break;
		}
	}
	mutex_unlock(&of_rmem_assigned_device_mutex);

	if (!rmem || !rmem->ops || !rmem->ops->device_release)
		return;

	rmem->ops->device_release(rmem, dev);
}
EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
Commit	Line	Data
3f0c8206 MS	1	/*
	2	* Device tree based initialization code for reserved memory.
	3	*
ae1add24	4	* Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
3f0c8206 MS	5	* Copyright (c) 2013,2014 Samsung Electronics Co., Ltd.
	6	* http://www.samsung.com
	7	* Author: Marek Szyprowski <m.szyprowski@samsung.com>
	8	* Author: Josh Cartwright <joshc@codeaurora.org>
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License as
	12	* published by the Free Software Foundation; either version 2 of the
	13	* License or (at your optional) any later version of the license.
	14	*/
	15
606ad42a RH	16	#define pr_fmt(fmt) "OF: reserved mem: " fmt
606ad42a RH	17
3f0c8206 MS	18	#include <linux/err.h>
	19	#include <linux/of.h>
	20	#include <linux/of_fdt.h>
	21	#include <linux/of_platform.h>
	22	#include <linux/mm.h>
	23	#include <linux/sizes.h>
	24	#include <linux/of_reserved_mem.h>
ae1add24	25	#include <linux/sort.h>
59ce4039	26	#include <linux/slab.h>
3f0c8206 MS	27
	28	#define MAX_RESERVED_REGIONS 16
	29	static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
	30	static int reserved_mem_count;
	31
	32	#if defined(CONFIG_HAVE_MEMBLOCK)
	33	#include <linux/memblock.h>
	34	int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
	35	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
	36	phys_addr_t *res_base)
	37	{
e53b50c0	38	phys_addr_t base;
3f0c8206 MS	39	/*
	40	* We use __memblock_alloc_base() because memblock_alloc_base()
	41	* panic()s on allocation failure.
	42	*/
e53b50c0 VM	43	end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
e53b50c0 VM	44	base = __memblock_alloc_base(size, align, end);
3f0c8206 MS	45	if (!base)
	46	return -ENOMEM;
	47
	48	/*
	49	* Check if the allocated region fits in to start..end window
	50	*/
	51	if (base < start) {
	52	memblock_free(base, size);
	53	return -ENOMEM;
	54	}
	55
	56	*res_base = base;
	57	if (nomap)
	58	return memblock_remove(base, size);
	59	return 0;
	60	}
	61	#else
	62	int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
	63	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
	64	phys_addr_t *res_base)
	65	{
	66	pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
	67	size, nomap ? " (nomap)" : "");
	68	return -ENOSYS;
	69	}
	70	#endif
	71
	72	/**
	73	* res_mem_save_node() - save fdt node for second pass initialization
	74	*/
	75	void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
	76	phys_addr_t base, phys_addr_t size)
	77	{
	78	struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
	79
	80	if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
606ad42a	81	pr_err("not enough space all defined regions.\n");
3f0c8206 MS	82	return;
	83	}
	84
	85	rmem->fdt_node = node;
	86	rmem->name = uname;
	87	rmem->base = base;
	88	rmem->size = size;
	89
	90	reserved_mem_count++;
	91	return;
	92	}
	93
	94	/**
	95	* res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
	96	* and 'alloc-ranges' properties
	97	*/
	98	static int __init __reserved_mem_alloc_size(unsigned long node,
	99	const char uname, phys_addr_t res_base, phys_addr_t *res_size)
	100	{
	101	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
	102	phys_addr_t start = 0, end = 0;
	103	phys_addr_t base = 0, align = 0, size;
9d0c4dfe RH	104	int len;
9d0c4dfe RH	105	const __be32 *prop;
3f0c8206 MS	106	int nomap;
	107	int ret;
	108
	109	prop = of_get_flat_dt_prop(node, "size", &len);
	110	if (!prop)
	111	return -EINVAL;
	112
	113	if (len != dt_root_size_cells * sizeof(__be32)) {
606ad42a	114	pr_err("invalid size property in '%s' node.\n", uname);
3f0c8206 MS	115	return -EINVAL;
	116	}
	117	size = dt_mem_next_cell(dt_root_size_cells, &prop);
	118
	119	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
	120
	121	prop = of_get_flat_dt_prop(node, "alignment", &len);
	122	if (prop) {
	123	if (len != dt_root_addr_cells * sizeof(__be32)) {
606ad42a	124	pr_err("invalid alignment property in '%s' node.\n",
3f0c8206 MS	125	uname);
	126	return -EINVAL;
	127	}
	128	align = dt_mem_next_cell(dt_root_addr_cells, &prop);
	129	}
	130
1cc8e345	131	/* Need adjust the alignment to satisfy the CMA requirement */
7d482813 J	132	if (IS_ENABLED(CONFIG_CMA)
	133	&& of_flat_dt_is_compatible(node, "shared-dma-pool")
	134	&& of_get_flat_dt_prop(node, "reusable", NULL)
aaaab56d SR	135	&& !of_get_flat_dt_prop(node, "no-map", NULL)) {
	136	unsigned long order =
	137	max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
	138
	139	align = max(align, (phys_addr_t)PAGE_SIZE << order);
	140	}
1cc8e345	141
3f0c8206 MS	142	prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
	143	if (prop) {
	144
	145	if (len % t_len != 0) {
606ad42a	146	pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
3f0c8206 MS	147	uname);
	148	return -EINVAL;
	149	}
	150
	151	base = 0;
	152
	153	while (len > 0) {
	154	start = dt_mem_next_cell(dt_root_addr_cells, &prop);
	155	end = start + dt_mem_next_cell(dt_root_size_cells,
	156	&prop);
	157
	158	ret = early_init_dt_alloc_reserved_memory_arch(size,
	159	align, start, end, nomap, &base);
	160	if (ret == 0) {
606ad42a	161	pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
3f0c8206 MS	162	uname, &base,
	163	(unsigned long)size / SZ_1M);
	164	break;
	165	}
	166	len -= t_len;
	167	}
	168
	169	} else {
	170	ret = early_init_dt_alloc_reserved_memory_arch(size, align,
	171	0, 0, nomap, &base);
	172	if (ret == 0)
606ad42a	173	pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
3f0c8206 MS	174	uname, &base, (unsigned long)size / SZ_1M);
	175	}
	176
	177	if (base == 0) {
606ad42a	178	pr_info("failed to allocate memory for node '%s'\n", uname);
3f0c8206 MS	179	return -ENOMEM;
	180	}
	181
	182	*res_base = base;
	183	*res_size = size;
	184
	185	return 0;
	186	}
	187
f618c470 MS	188	static const struct of_device_id __rmem_of_table_sentinel
	189	__used __section(__reservedmem_of_table_end);
	190
	191	/**
	192	* res_mem_init_node() - call region specific reserved memory init code
	193	*/
	194	static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
	195	{
	196	extern const struct of_device_id __reservedmem_of_table[];
	197	const struct of_device_id *i;
	198
	199	for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
	200	reservedmem_of_init_fn initfn = i->data;
	201	const char *compat = i->compatible;
	202
	203	if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
	204	continue;
	205
9dd31075	206	if (initfn(rmem) == 0) {
606ad42a	207	pr_info("initialized node %s, compatible id %s\n",
f618c470 MS	208	rmem->name, compat);
	209	return 0;
	210	}
	211	}
	212	return -ENOENT;
	213	}
	214
ae1add24 MH	215	static int __init __rmem_cmp(const void a, const void b)
	216	{
	217	const struct reserved_mem ra = a, rb = b;
	218
9eb8cd2b ME	219	if (ra->base < rb->base)
	220	return -1;
	221
	222	if (ra->base > rb->base)
	223	return 1;
	224
	225	return 0;
ae1add24 MH	226	}
	227
	228	static void __init __rmem_check_for_overlap(void)
	229	{
	230	int i;
	231
	232	if (reserved_mem_count < 2)
	233	return;
	234
	235	sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
	236	__rmem_cmp, NULL);
	237	for (i = 0; i < reserved_mem_count - 1; i++) {
	238	struct reserved_mem this, next;
	239
	240	this = &reserved_mem[i];
	241	next = &reserved_mem[i + 1];
	242	if (!(this->base && next->base))
	243	continue;
	244	if (this->base + this->size > next->base) {
	245	phys_addr_t this_end, next_end;
	246
	247	this_end = this->base + this->size;
	248	next_end = next->base + next->size;
606ad42a	249	pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
85a1c77f ME	250	this->name, &this->base, &this_end,
85a1c77f ME	251	next->name, &next->base, &next_end);
ae1add24 MH	252	}
	253	}
	254	}
	255
3f0c8206 MS	256	/**
	257	* fdt_init_reserved_mem - allocate and init all saved reserved memory regions
	258	*/
	259	void __init fdt_init_reserved_mem(void)
	260	{
	261	int i;
ae1add24 MH	262
	263	/* check for overlapping reserved regions */
	264	__rmem_check_for_overlap();
	265
3f0c8206 MS	266	for (i = 0; i < reserved_mem_count; i++) {
	267	struct reserved_mem *rmem = &reserved_mem[i];
	268	unsigned long node = rmem->fdt_node;
9dcfee01 MS	269	int len;
9dcfee01 MS	270	const __be32 *prop;
3f0c8206 MS	271	int err = 0;
3f0c8206 MS	272
9dcfee01 MS	273	prop = of_get_flat_dt_prop(node, "phandle", &len);
	274	if (!prop)
	275	prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
	276	if (prop)
	277	rmem->phandle = of_read_number(prop, len/4);
	278
3f0c8206 MS	279	if (rmem->size == 0)
	280	err = __reserved_mem_alloc_size(node, rmem->name,
	281	&rmem->base, &rmem->size);
f618c470 MS	282	if (err == 0)
f618c470 MS	283	__reserved_mem_init_node(rmem);
3f0c8206 MS	284	}
3f0c8206 MS	285	}
9dcfee01 MS	286
	287	static inline struct reserved_mem __find_rmem(struct device_node node)
	288	{
	289	unsigned int i;
	290
	291	if (!node->phandle)
	292	return NULL;
	293
	294	for (i = 0; i < reserved_mem_count; i++)
	295	if (reserved_mem[i].phandle == node->phandle)
	296	return &reserved_mem[i];
	297	return NULL;
	298	}
	299
59ce4039 MS	300	struct rmem_assigned_device {
	301	struct device *dev;
	302	struct reserved_mem *rmem;
	303	struct list_head list;
	304	};
	305
	306	static LIST_HEAD(of_rmem_assigned_device_list);
	307	static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
	308
9dcfee01	309	/**
59ce4039 MS	310	* of_reserved_mem_device_init_by_idx() - assign reserved memory region to
	311	* given device
	312	* @dev: Pointer to the device to configure
	313	* @np: Pointer to the device_node with 'reserved-memory' property
	314	* @idx: Index of selected region
9dcfee01	315	*
59ce4039 MS	316	* This function assigns respective DMA-mapping operations based on reserved
	317	* memory region specified by 'memory-region' property in @np node to the @dev
	318	* device. When driver needs to use more than one reserved memory region, it
	319	* should allocate child devices and initialize regions by name for each of
	320	* child device.
	321	*
	322	* Returns error code or zero on success.
9dcfee01	323	*/
59ce4039 MS	324	int of_reserved_mem_device_init_by_idx(struct device *dev,
59ce4039 MS	325	struct device_node *np, int idx)
9dcfee01	326	{
59ce4039 MS	327	struct rmem_assigned_device *rd;
59ce4039 MS	328	struct device_node *target;
9dcfee01	329	struct reserved_mem *rmem;
47f29df7	330	int ret;
9dcfee01	331
59ce4039 MS	332	if (!np \|\| !dev)
	333	return -EINVAL;
	334
	335	target = of_parse_phandle(np, "memory-region", idx);
	336	if (!target)
9f5a802b	337	return -ENODEV;
9dcfee01	338
59ce4039 MS	339	rmem = __find_rmem(target);
59ce4039 MS	340	of_node_put(target);
9dcfee01 MS	341
9dcfee01 MS	342	if (!rmem \|\| !rmem->ops \|\| !rmem->ops->device_init)
47f29df7 MS	343	return -EINVAL;
47f29df7 MS	344
59ce4039 MS	345	rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
	346	if (!rd)
	347	return -ENOMEM;
	348
47f29df7	349	ret = rmem->ops->device_init(rmem, dev);
59ce4039 MS	350	if (ret == 0) {
	351	rd->dev = dev;
	352	rd->rmem = rmem;
	353
	354	mutex_lock(&of_rmem_assigned_device_mutex);
	355	list_add(&rd->list, &of_rmem_assigned_device_list);
	356	mutex_unlock(&of_rmem_assigned_device_mutex);
	357
47f29df7	358	dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
59ce4039 MS	359	} else {
	360	kfree(rd);
	361	}
9dcfee01	362
47f29df7	363	return ret;
9dcfee01	364	}
59ce4039	365	EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
9dcfee01 MS	366
	367	/**
	368	* of_reserved_mem_device_release() - release reserved memory device structures
59ce4039	369	* @dev: Pointer to the device to deconfigure
9dcfee01 MS	370	*
	371	* This function releases structures allocated for memory region handling for
	372	* the given device.
	373	*/
	374	void of_reserved_mem_device_release(struct device *dev)
	375	{
59ce4039 MS	376	struct rmem_assigned_device *rd;
	377	struct reserved_mem *rmem = NULL;
	378
	379	mutex_lock(&of_rmem_assigned_device_mutex);
	380	list_for_each_entry(rd, &of_rmem_assigned_device_list, list) {
	381	if (rd->dev == dev) {
	382	rmem = rd->rmem;
	383	list_del(&rd->list);
	384	kfree(rd);
	385	break;
	386	}
	387	}
	388	mutex_unlock(&of_rmem_assigned_device_mutex);
9dcfee01 MS	389
	390	if (!rmem \|\| !rmem->ops \|\| !rmem->ops->device_release)
	391	return;
	392
	393	rmem->ops->device_release(rmem, dev);
	394	}
615fde79	395	EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);