[linux-2.6-block.git] / drivers / of / of_reserved_mem.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * 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>
 */

#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>
#include <linux/memblock.h>

#define MAX_RESERVED_REGIONS	32
static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
static int reserved_mem_count;

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;
	align = !align ? SMP_CACHE_BYTES : align;
	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;
}

/**
 * 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);
		/* ensure that dma_ops is set for virtual devices
		 * using reserved memory
		 */
		of_dma_configure(dev, np, true);

		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);

/**
 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
 * @np:		node pointer of the desired reserved-memory region
 *
 * This function allows drivers to acquire a reference to the reserved_mem
 * struct based on a device node handle.
 *
 * Returns a reserved_mem reference, or NULL on error.
 */
struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
{
	const char *name;
	int i;

	if (!np->full_name)
		return NULL;

	name = kbasename(np->full_name);
	for (i = 0; i < reserved_mem_count; i++)
		if (!strcmp(reserved_mem[i].name, name))
			return &reserved_mem[i];

	return NULL;
}
EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);
Commit	Line	Data
af6074fc	1	// SPDX-License-Identifier: GPL-2.0+
3f0c8206 MS	2	/*
	3	* Device tree based initialization code for reserved memory.
	4	*
ae1add24	5	* Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
3f0c8206 MS	6	* Copyright (c) 2013,2014 Samsung Electronics Co., Ltd.
	7	* http://www.samsung.com
	8	* Author: Marek Szyprowski <m.szyprowski@samsung.com>
	9	* Author: Josh Cartwright <joshc@codeaurora.org>
3f0c8206 MS	10	*/
3f0c8206 MS	11
606ad42a RH	12	#define pr_fmt(fmt) "OF: reserved mem: " fmt
606ad42a RH	13
3f0c8206 MS	14	#include <linux/err.h>
	15	#include <linux/of.h>
	16	#include <linux/of_fdt.h>
	17	#include <linux/of_platform.h>
	18	#include <linux/mm.h>
	19	#include <linux/sizes.h>
	20	#include <linux/of_reserved_mem.h>
ae1add24	21	#include <linux/sort.h>
59ce4039	22	#include <linux/slab.h>
aca52c39	23	#include <linux/memblock.h>
3f0c8206	24
22f8cc6e	25	#define MAX_RESERVED_REGIONS 32
3f0c8206 MS	26	static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
	27	static int reserved_mem_count;
	28
3f0c8206 MS	29	int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
	30	phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
	31	phys_addr_t *res_base)
	32	{
e53b50c0	33	phys_addr_t base;
3f0c8206 MS	34	/*
	35	* We use __memblock_alloc_base() because memblock_alloc_base()
	36	* panic()s on allocation failure.
	37	*/
e53b50c0	38	end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
7e1c4e27	39	align = !align ? SMP_CACHE_BYTES : align;
e53b50c0	40	base = __memblock_alloc_base(size, align, end);
3f0c8206 MS	41	if (!base)
	42	return -ENOMEM;
	43
	44	/*
	45	* Check if the allocated region fits in to start..end window
	46	*/
	47	if (base < start) {
	48	memblock_free(base, size);
	49	return -ENOMEM;
	50	}
	51
	52	*res_base = base;
	53	if (nomap)
	54	return memblock_remove(base, size);
	55	return 0;
	56	}
3f0c8206 MS	57
	58	/**
	59	* res_mem_save_node() - save fdt node for second pass initialization
	60	*/
	61	void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
	62	phys_addr_t base, phys_addr_t size)
	63	{
	64	struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
	65
	66	if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
606ad42a	67	pr_err("not enough space all defined regions.\n");
3f0c8206 MS	68	return;
	69	}
	70
	71	rmem->fdt_node = node;
	72	rmem->name = uname;
	73	rmem->base = base;
	74	rmem->size = size;
	75
	76	reserved_mem_count++;
	77	return;
	78	}
	79
	80	/**
	81	* res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
	82	* and 'alloc-ranges' properties
	83	*/
	84	static int __init __reserved_mem_alloc_size(unsigned long node,
	85	const char uname, phys_addr_t res_base, phys_addr_t *res_size)
	86	{
	87	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
	88	phys_addr_t start = 0, end = 0;
	89	phys_addr_t base = 0, align = 0, size;
9d0c4dfe RH	90	int len;
9d0c4dfe RH	91	const __be32 *prop;
3f0c8206 MS	92	int nomap;
	93	int ret;
	94
	95	prop = of_get_flat_dt_prop(node, "size", &len);
	96	if (!prop)
	97	return -EINVAL;
	98
	99	if (len != dt_root_size_cells * sizeof(__be32)) {
606ad42a	100	pr_err("invalid size property in '%s' node.\n", uname);
3f0c8206 MS	101	return -EINVAL;
	102	}
	103	size = dt_mem_next_cell(dt_root_size_cells, &prop);
	104
	105	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
	106
	107	prop = of_get_flat_dt_prop(node, "alignment", &len);
	108	if (prop) {
	109	if (len != dt_root_addr_cells * sizeof(__be32)) {
606ad42a	110	pr_err("invalid alignment property in '%s' node.\n",
3f0c8206 MS	111	uname);
	112	return -EINVAL;
	113	}
	114	align = dt_mem_next_cell(dt_root_addr_cells, &prop);
	115	}
	116
1cc8e345	117	/* Need adjust the alignment to satisfy the CMA requirement */
7d482813 J	118	if (IS_ENABLED(CONFIG_CMA)
	119	&& of_flat_dt_is_compatible(node, "shared-dma-pool")
	120	&& of_get_flat_dt_prop(node, "reusable", NULL)
aaaab56d SR	121	&& !of_get_flat_dt_prop(node, "no-map", NULL)) {
	122	unsigned long order =
	123	max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
	124
	125	align = max(align, (phys_addr_t)PAGE_SIZE << order);
	126	}
1cc8e345	127
3f0c8206 MS	128	prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
	129	if (prop) {
	130
	131	if (len % t_len != 0) {
606ad42a	132	pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
3f0c8206 MS	133	uname);
	134	return -EINVAL;
	135	}
	136
	137	base = 0;
	138
	139	while (len > 0) {
	140	start = dt_mem_next_cell(dt_root_addr_cells, &prop);
	141	end = start + dt_mem_next_cell(dt_root_size_cells,
	142	&prop);
	143
	144	ret = early_init_dt_alloc_reserved_memory_arch(size,
	145	align, start, end, nomap, &base);
	146	if (ret == 0) {
606ad42a	147	pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
3f0c8206 MS	148	uname, &base,
	149	(unsigned long)size / SZ_1M);
	150	break;
	151	}
	152	len -= t_len;
	153	}
	154
	155	} else {
	156	ret = early_init_dt_alloc_reserved_memory_arch(size, align,
	157	0, 0, nomap, &base);
	158	if (ret == 0)
606ad42a	159	pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
3f0c8206 MS	160	uname, &base, (unsigned long)size / SZ_1M);
	161	}
	162
	163	if (base == 0) {
606ad42a	164	pr_info("failed to allocate memory for node '%s'\n", uname);
3f0c8206 MS	165	return -ENOMEM;
	166	}
	167
	168	*res_base = base;
	169	*res_size = size;
	170
	171	return 0;
	172	}
	173
f618c470 MS	174	static const struct of_device_id __rmem_of_table_sentinel
	175	__used __section(__reservedmem_of_table_end);
	176
	177	/**
	178	* res_mem_init_node() - call region specific reserved memory init code
	179	*/
	180	static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
	181	{
	182	extern const struct of_device_id __reservedmem_of_table[];
	183	const struct of_device_id *i;
	184
	185	for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
df3ed932	186	reservedmem_of_init_fn initfn = i->data;
f618c470 MS	187	const char *compat = i->compatible;
	188
	189	if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
	190	continue;
	191
9dd31075	192	if (initfn(rmem) == 0) {
606ad42a	193	pr_info("initialized node %s, compatible id %s\n",
f618c470 MS	194	rmem->name, compat);
	195	return 0;
	196	}
	197	}
	198	return -ENOENT;
	199	}
	200
ae1add24 MH	201	static int __init __rmem_cmp(const void a, const void b)
	202	{
	203	const struct reserved_mem ra = a, rb = b;
	204
9eb8cd2b ME	205	if (ra->base < rb->base)
	206	return -1;
	207
	208	if (ra->base > rb->base)
	209	return 1;
	210
	211	return 0;
ae1add24 MH	212	}
	213
	214	static void __init __rmem_check_for_overlap(void)
	215	{
	216	int i;
	217
	218	if (reserved_mem_count < 2)
	219	return;
	220
	221	sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
	222	__rmem_cmp, NULL);
	223	for (i = 0; i < reserved_mem_count - 1; i++) {
	224	struct reserved_mem this, next;
	225
	226	this = &reserved_mem[i];
	227	next = &reserved_mem[i + 1];
	228	if (!(this->base && next->base))
	229	continue;
	230	if (this->base + this->size > next->base) {
	231	phys_addr_t this_end, next_end;
	232
	233	this_end = this->base + this->size;
	234	next_end = next->base + next->size;
606ad42a	235	pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
85a1c77f ME	236	this->name, &this->base, &this_end,
85a1c77f ME	237	next->name, &next->base, &next_end);
ae1add24 MH	238	}
	239	}
	240	}
	241
3f0c8206 MS	242	/**
	243	* fdt_init_reserved_mem - allocate and init all saved reserved memory regions
	244	*/
	245	void __init fdt_init_reserved_mem(void)
	246	{
	247	int i;
ae1add24 MH	248
	249	/* check for overlapping reserved regions */
	250	__rmem_check_for_overlap();
	251
3f0c8206 MS	252	for (i = 0; i < reserved_mem_count; i++) {
	253	struct reserved_mem *rmem = &reserved_mem[i];
	254	unsigned long node = rmem->fdt_node;
9dcfee01 MS	255	int len;
9dcfee01 MS	256	const __be32 *prop;
3f0c8206 MS	257	int err = 0;
3f0c8206 MS	258
9dcfee01 MS	259	prop = of_get_flat_dt_prop(node, "phandle", &len);
	260	if (!prop)
	261	prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
	262	if (prop)
	263	rmem->phandle = of_read_number(prop, len/4);
	264
3f0c8206 MS	265	if (rmem->size == 0)
	266	err = __reserved_mem_alloc_size(node, rmem->name,
	267	&rmem->base, &rmem->size);
f618c470 MS	268	if (err == 0)
f618c470 MS	269	__reserved_mem_init_node(rmem);
3f0c8206 MS	270	}
3f0c8206 MS	271	}
9dcfee01 MS	272
	273	static inline struct reserved_mem __find_rmem(struct device_node node)
	274	{
	275	unsigned int i;
	276
	277	if (!node->phandle)
	278	return NULL;
	279
	280	for (i = 0; i < reserved_mem_count; i++)
	281	if (reserved_mem[i].phandle == node->phandle)
	282	return &reserved_mem[i];
	283	return NULL;
	284	}
	285
59ce4039 MS	286	struct rmem_assigned_device {
	287	struct device *dev;
	288	struct reserved_mem *rmem;
	289	struct list_head list;
	290	};
	291
	292	static LIST_HEAD(of_rmem_assigned_device_list);
	293	static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
	294
9dcfee01	295	/**
59ce4039 MS	296	* of_reserved_mem_device_init_by_idx() - assign reserved memory region to
	297	* given device
	298	* @dev: Pointer to the device to configure
	299	* @np: Pointer to the device_node with 'reserved-memory' property
	300	* @idx: Index of selected region
9dcfee01	301	*
59ce4039 MS	302	* This function assigns respective DMA-mapping operations based on reserved
	303	* memory region specified by 'memory-region' property in @np node to the @dev
	304	* device. When driver needs to use more than one reserved memory region, it
	305	* should allocate child devices and initialize regions by name for each of
	306	* child device.
	307	*
	308	* Returns error code or zero on success.
9dcfee01	309	*/
59ce4039 MS	310	int of_reserved_mem_device_init_by_idx(struct device *dev,
59ce4039 MS	311	struct device_node *np, int idx)
9dcfee01	312	{
59ce4039 MS	313	struct rmem_assigned_device *rd;
59ce4039 MS	314	struct device_node *target;
9dcfee01	315	struct reserved_mem *rmem;
47f29df7	316	int ret;
9dcfee01	317
59ce4039 MS	318	if (!np \|\| !dev)
	319	return -EINVAL;
	320
	321	target = of_parse_phandle(np, "memory-region", idx);
	322	if (!target)
9f5a802b	323	return -ENODEV;
9dcfee01	324
59ce4039 MS	325	rmem = __find_rmem(target);
59ce4039 MS	326	of_node_put(target);
9dcfee01 MS	327
9dcfee01 MS	328	if (!rmem \|\| !rmem->ops \|\| !rmem->ops->device_init)
47f29df7 MS	329	return -EINVAL;
47f29df7 MS	330
59ce4039 MS	331	rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
	332	if (!rd)
	333	return -ENOMEM;
	334
47f29df7	335	ret = rmem->ops->device_init(rmem, dev);
59ce4039 MS	336	if (ret == 0) {
	337	rd->dev = dev;
	338	rd->rmem = rmem;
	339
	340	mutex_lock(&of_rmem_assigned_device_mutex);
	341	list_add(&rd->list, &of_rmem_assigned_device_list);
	342	mutex_unlock(&of_rmem_assigned_device_mutex);
a3b398e6 SM	343	/* ensure that dma_ops is set for virtual devices
	344	* using reserved memory
	345	*/
3d6ce86e	346	of_dma_configure(dev, np, true);
59ce4039	347
47f29df7	348	dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
59ce4039 MS	349	} else {
	350	kfree(rd);
	351	}
9dcfee01	352
47f29df7	353	return ret;
9dcfee01	354	}
59ce4039	355	EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
9dcfee01 MS	356
	357	/**
	358	* of_reserved_mem_device_release() - release reserved memory device structures
59ce4039	359	* @dev: Pointer to the device to deconfigure
9dcfee01 MS	360	*
	361	* This function releases structures allocated for memory region handling for
	362	* the given device.
	363	*/
	364	void of_reserved_mem_device_release(struct device *dev)
	365	{
59ce4039 MS	366	struct rmem_assigned_device *rd;
	367	struct reserved_mem *rmem = NULL;
	368
	369	mutex_lock(&of_rmem_assigned_device_mutex);
	370	list_for_each_entry(rd, &of_rmem_assigned_device_list, list) {
	371	if (rd->dev == dev) {
	372	rmem = rd->rmem;
	373	list_del(&rd->list);
	374	kfree(rd);
	375	break;
	376	}
	377	}
	378	mutex_unlock(&of_rmem_assigned_device_mutex);
9dcfee01 MS	379
	380	if (!rmem \|\| !rmem->ops \|\| !rmem->ops->device_release)
	381	return;
	382
	383	rmem->ops->device_release(rmem, dev);
	384	}
615fde79	385	EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
eb297bc7 BA	386
	387	/**
	388	* of_reserved_mem_lookup() - acquire reserved_mem from a device node
	389	* @np: node pointer of the desired reserved-memory region
	390	*
	391	* This function allows drivers to acquire a reference to the reserved_mem
	392	* struct based on a device node handle.
	393	*
	394	* Returns a reserved_mem reference, or NULL on error.
	395	*/
	396	struct reserved_mem of_reserved_mem_lookup(struct device_node np)
	397	{
	398	const char *name;
	399	int i;
	400
	401	if (!np->full_name)
	402	return NULL;
	403
	404	name = kbasename(np->full_name);
	405	for (i = 0; i < reserved_mem_count; i++)
	406	if (!strcmp(reserved_mem[i].name, name))
	407	return &reserved_mem[i];
	408
	409	return NULL;
	410	}
	411	EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);