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1/*
2 * Device tree based initialization code for reserved memory.
3 *
4 * Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
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
16#include <linux/err.h>
17#include <linux/of.h>
18#include <linux/of_fdt.h>
19#include <linux/of_platform.h>
20#include <linux/mm.h>
21#include <linux/sizes.h>
22#include <linux/of_reserved_mem.h>
23#include <linux/sort.h>
24
25#define MAX_RESERVED_REGIONS 16
26static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
27static int reserved_mem_count;
28
29#if defined(CONFIG_HAVE_MEMBLOCK)
30#include <linux/memblock.h>
31int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
32 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
33 phys_addr_t *res_base)
34{
35 phys_addr_t base;
36 /*
37 * We use __memblock_alloc_base() because memblock_alloc_base()
38 * panic()s on allocation failure.
39 */
40 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
41 base = __memblock_alloc_base(size, align, end);
42 if (!base)
43 return -ENOMEM;
44
45 /*
46 * Check if the allocated region fits in to start..end window
47 */
48 if (base < start) {
49 memblock_free(base, size);
50 return -ENOMEM;
51 }
52
53 *res_base = base;
54 if (nomap)
55 return memblock_remove(base, size);
56 return 0;
57}
58#else
59int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
60 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
61 phys_addr_t *res_base)
62{
63 pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
64 size, nomap ? " (nomap)" : "");
65 return -ENOSYS;
66}
67#endif
68
69/**
70 * res_mem_save_node() - save fdt node for second pass initialization
71 */
72void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
73 phys_addr_t base, phys_addr_t size)
74{
75 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
76
77 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
78 pr_err("Reserved memory: not enough space all defined regions.\n");
79 return;
80 }
81
82 rmem->fdt_node = node;
83 rmem->name = uname;
84 rmem->base = base;
85 rmem->size = size;
86
87 reserved_mem_count++;
88 return;
89}
90
91/**
92 * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
93 * and 'alloc-ranges' properties
94 */
95static int __init __reserved_mem_alloc_size(unsigned long node,
96 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
97{
98 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
99 phys_addr_t start = 0, end = 0;
100 phys_addr_t base = 0, align = 0, size;
101 int len;
102 const __be32 *prop;
103 int nomap;
104 int ret;
105
106 prop = of_get_flat_dt_prop(node, "size", &len);
107 if (!prop)
108 return -EINVAL;
109
110 if (len != dt_root_size_cells * sizeof(__be32)) {
111 pr_err("Reserved memory: invalid size property in '%s' node.\n",
112 uname);
113 return -EINVAL;
114 }
115 size = dt_mem_next_cell(dt_root_size_cells, &prop);
116
117 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
118
119 prop = of_get_flat_dt_prop(node, "alignment", &len);
120 if (prop) {
121 if (len != dt_root_addr_cells * sizeof(__be32)) {
122 pr_err("Reserved memory: invalid alignment property in '%s' node.\n",
123 uname);
124 return -EINVAL;
125 }
126 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
127 }
128
129 /* Need adjust the alignment to satisfy the CMA requirement */
130 if (IS_ENABLED(CONFIG_CMA) && of_flat_dt_is_compatible(node, "shared-dma-pool"))
131 align = max(align, (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order));
132
133 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
134 if (prop) {
135
136 if (len % t_len != 0) {
137 pr_err("Reserved memory: invalid alloc-ranges property in '%s', skipping node.\n",
138 uname);
139 return -EINVAL;
140 }
141
142 base = 0;
143
144 while (len > 0) {
145 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
146 end = start + dt_mem_next_cell(dt_root_size_cells,
147 &prop);
148
149 ret = early_init_dt_alloc_reserved_memory_arch(size,
150 align, start, end, nomap, &base);
151 if (ret == 0) {
152 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n",
153 uname, &base,
154 (unsigned long)size / SZ_1M);
155 break;
156 }
157 len -= t_len;
158 }
159
160 } else {
161 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
162 0, 0, nomap, &base);
163 if (ret == 0)
164 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n",
165 uname, &base, (unsigned long)size / SZ_1M);
166 }
167
168 if (base == 0) {
169 pr_info("Reserved memory: failed to allocate memory for node '%s'\n",
170 uname);
171 return -ENOMEM;
172 }
173
174 *res_base = base;
175 *res_size = size;
176
177 return 0;
178}
179
180static const struct of_device_id __rmem_of_table_sentinel
181 __used __section(__reservedmem_of_table_end);
182
183/**
184 * res_mem_init_node() - call region specific reserved memory init code
185 */
186static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
187{
188 extern const struct of_device_id __reservedmem_of_table[];
189 const struct of_device_id *i;
190
191 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
192 reservedmem_of_init_fn initfn = i->data;
193 const char *compat = i->compatible;
194
195 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
196 continue;
197
198 if (initfn(rmem) == 0) {
199 pr_info("Reserved memory: initialized node %s, compatible id %s\n",
200 rmem->name, compat);
201 return 0;
202 }
203 }
204 return -ENOENT;
205}
206
207static int __init __rmem_cmp(const void *a, const void *b)
208{
209 const struct reserved_mem *ra = a, *rb = b;
210
211 if (ra->base < rb->base)
212 return -1;
213
214 if (ra->base > rb->base)
215 return 1;
216
217 return 0;
218}
219
220static void __init __rmem_check_for_overlap(void)
221{
222 int i;
223
224 if (reserved_mem_count < 2)
225 return;
226
227 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
228 __rmem_cmp, NULL);
229 for (i = 0; i < reserved_mem_count - 1; i++) {
230 struct reserved_mem *this, *next;
231
232 this = &reserved_mem[i];
233 next = &reserved_mem[i + 1];
234 if (!(this->base && next->base))
235 continue;
236 if (this->base + this->size > next->base) {
237 phys_addr_t this_end, next_end;
238
239 this_end = this->base + this->size;
240 next_end = next->base + next->size;
241 pr_err("Reserved memory: OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
242 this->name, &this->base, &this_end,
243 next->name, &next->base, &next_end);
244 }
245 }
246}
247
248/**
249 * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
250 */
251void __init fdt_init_reserved_mem(void)
252{
253 int i;
254
255 /* check for overlapping reserved regions */
256 __rmem_check_for_overlap();
257
258 for (i = 0; i < reserved_mem_count; i++) {
259 struct reserved_mem *rmem = &reserved_mem[i];
260 unsigned long node = rmem->fdt_node;
261 int len;
262 const __be32 *prop;
263 int err = 0;
264
265 prop = of_get_flat_dt_prop(node, "phandle", &len);
266 if (!prop)
267 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
268 if (prop)
269 rmem->phandle = of_read_number(prop, len/4);
270
271 if (rmem->size == 0)
272 err = __reserved_mem_alloc_size(node, rmem->name,
273 &rmem->base, &rmem->size);
274 if (err == 0)
275 __reserved_mem_init_node(rmem);
276 }
277}
278
279static inline struct reserved_mem *__find_rmem(struct device_node *node)
280{
281 unsigned int i;
282
283 if (!node->phandle)
284 return NULL;
285
286 for (i = 0; i < reserved_mem_count; i++)
287 if (reserved_mem[i].phandle == node->phandle)
288 return &reserved_mem[i];
289 return NULL;
290}
291
292/**
293 * of_reserved_mem_device_init() - assign reserved memory region to given device
294 *
295 * This function assign memory region pointed by "memory-region" device tree
296 * property to the given device.
297 */
298int of_reserved_mem_device_init(struct device *dev)
299{
300 struct reserved_mem *rmem;
301 struct device_node *np;
302 int ret;
303
304 np = of_parse_phandle(dev->of_node, "memory-region", 0);
305 if (!np)
306 return -ENODEV;
307
308 rmem = __find_rmem(np);
309 of_node_put(np);
310
311 if (!rmem || !rmem->ops || !rmem->ops->device_init)
312 return -EINVAL;
313
314 ret = rmem->ops->device_init(rmem, dev);
315 if (ret == 0)
316 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
317
318 return ret;
319}
320EXPORT_SYMBOL_GPL(of_reserved_mem_device_init);
321
322/**
323 * of_reserved_mem_device_release() - release reserved memory device structures
324 *
325 * This function releases structures allocated for memory region handling for
326 * the given device.
327 */
328void of_reserved_mem_device_release(struct device *dev)
329{
330 struct reserved_mem *rmem;
331 struct device_node *np;
332
333 np = of_parse_phandle(dev->of_node, "memory-region", 0);
334 if (!np)
335 return;
336
337 rmem = __find_rmem(np);
338 of_node_put(np);
339
340 if (!rmem || !rmem->ops || !rmem->ops->device_release)
341 return;
342
343 rmem->ops->device_release(rmem, dev);
344}
345EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Device tree based initialization code for reserved memory.
4 *
5 * Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
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>
10 */
11
12#define pr_fmt(fmt) "OF: reserved mem: " fmt
13
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>
21#include <linux/sort.h>
22#include <linux/slab.h>
23#include <linux/memblock.h>
24#include <linux/kmemleak.h>
25#include <linux/cma.h>
26
27#include "of_private.h"
28
29#define MAX_RESERVED_REGIONS 64
30static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
31static int reserved_mem_count;
32
33static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
34 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
35 phys_addr_t *res_base)
36{
37 phys_addr_t base;
38 int err = 0;
39
40 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
41 align = !align ? SMP_CACHE_BYTES : align;
42 base = memblock_phys_alloc_range(size, align, start, end);
43 if (!base)
44 return -ENOMEM;
45
46 *res_base = base;
47 if (nomap) {
48 err = memblock_mark_nomap(base, size);
49 if (err)
50 memblock_phys_free(base, size);
51 }
52
53 kmemleak_ignore_phys(base);
54
55 return err;
56}
57
58/*
59 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
60 */
61void __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)) {
67 pr_err("not enough space for all defined regions.\n");
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 * __reserved_mem_alloc_in_range() - allocate reserved memory described with
82 * 'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing
83 * reserved regions to keep the reserved memory contiguous if possible.
84 */
85static int __init __reserved_mem_alloc_in_range(phys_addr_t size,
86 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
87 phys_addr_t *res_base)
88{
89 bool prev_bottom_up = memblock_bottom_up();
90 bool bottom_up = false, top_down = false;
91 int ret, i;
92
93 for (i = 0; i < reserved_mem_count; i++) {
94 struct reserved_mem *rmem = &reserved_mem[i];
95
96 /* Skip regions that were not reserved yet */
97 if (rmem->size == 0)
98 continue;
99
100 /*
101 * If range starts next to an existing reservation, use bottom-up:
102 * |....RRRR................RRRRRRRR..............|
103 * --RRRR------
104 */
105 if (start >= rmem->base && start <= (rmem->base + rmem->size))
106 bottom_up = true;
107
108 /*
109 * If range ends next to an existing reservation, use top-down:
110 * |....RRRR................RRRRRRRR..............|
111 * -------RRRR-----
112 */
113 if (end >= rmem->base && end <= (rmem->base + rmem->size))
114 top_down = true;
115 }
116
117 /* Change setting only if either bottom-up or top-down was selected */
118 if (bottom_up != top_down)
119 memblock_set_bottom_up(bottom_up);
120
121 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
122 start, end, nomap, res_base);
123
124 /* Restore old setting if needed */
125 if (bottom_up != top_down)
126 memblock_set_bottom_up(prev_bottom_up);
127
128 return ret;
129}
130
131/*
132 * __reserved_mem_alloc_size() - allocate reserved memory described by
133 * 'size', 'alignment' and 'alloc-ranges' properties.
134 */
135static int __init __reserved_mem_alloc_size(unsigned long node,
136 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
137{
138 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
139 phys_addr_t start = 0, end = 0;
140 phys_addr_t base = 0, align = 0, size;
141 int len;
142 const __be32 *prop;
143 bool nomap;
144 int ret;
145
146 prop = of_get_flat_dt_prop(node, "size", &len);
147 if (!prop)
148 return -EINVAL;
149
150 if (len != dt_root_size_cells * sizeof(__be32)) {
151 pr_err("invalid size property in '%s' node.\n", uname);
152 return -EINVAL;
153 }
154 size = dt_mem_next_cell(dt_root_size_cells, &prop);
155
156 prop = of_get_flat_dt_prop(node, "alignment", &len);
157 if (prop) {
158 if (len != dt_root_addr_cells * sizeof(__be32)) {
159 pr_err("invalid alignment property in '%s' node.\n",
160 uname);
161 return -EINVAL;
162 }
163 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
164 }
165
166 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
167
168 /* Need adjust the alignment to satisfy the CMA requirement */
169 if (IS_ENABLED(CONFIG_CMA)
170 && of_flat_dt_is_compatible(node, "shared-dma-pool")
171 && of_get_flat_dt_prop(node, "reusable", NULL)
172 && !nomap)
173 align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
174
175 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
176 if (prop) {
177
178 if (len % t_len != 0) {
179 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
180 uname);
181 return -EINVAL;
182 }
183
184 base = 0;
185
186 while (len > 0) {
187 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
188 end = start + dt_mem_next_cell(dt_root_size_cells,
189 &prop);
190
191 ret = __reserved_mem_alloc_in_range(size, align,
192 start, end, nomap, &base);
193 if (ret == 0) {
194 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
195 uname, &base,
196 (unsigned long)(size / SZ_1M));
197 break;
198 }
199 len -= t_len;
200 }
201
202 } else {
203 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
204 0, 0, nomap, &base);
205 if (ret == 0)
206 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
207 uname, &base, (unsigned long)(size / SZ_1M));
208 }
209
210 if (base == 0) {
211 pr_err("failed to allocate memory for node '%s': size %lu MiB\n",
212 uname, (unsigned long)(size / SZ_1M));
213 return -ENOMEM;
214 }
215
216 *res_base = base;
217 *res_size = size;
218
219 return 0;
220}
221
222static const struct of_device_id __rmem_of_table_sentinel
223 __used __section("__reservedmem_of_table_end");
224
225/*
226 * __reserved_mem_init_node() - call region specific reserved memory init code
227 */
228static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
229{
230 extern const struct of_device_id __reservedmem_of_table[];
231 const struct of_device_id *i;
232 int ret = -ENOENT;
233
234 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
235 reservedmem_of_init_fn initfn = i->data;
236 const char *compat = i->compatible;
237
238 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
239 continue;
240
241 ret = initfn(rmem);
242 if (ret == 0) {
243 pr_info("initialized node %s, compatible id %s\n",
244 rmem->name, compat);
245 break;
246 }
247 }
248 return ret;
249}
250
251static int __init __rmem_cmp(const void *a, const void *b)
252{
253 const struct reserved_mem *ra = a, *rb = b;
254
255 if (ra->base < rb->base)
256 return -1;
257
258 if (ra->base > rb->base)
259 return 1;
260
261 /*
262 * Put the dynamic allocations (address == 0, size == 0) before static
263 * allocations at address 0x0 so that overlap detection works
264 * correctly.
265 */
266 if (ra->size < rb->size)
267 return -1;
268 if (ra->size > rb->size)
269 return 1;
270
271 if (ra->fdt_node < rb->fdt_node)
272 return -1;
273 if (ra->fdt_node > rb->fdt_node)
274 return 1;
275
276 return 0;
277}
278
279static void __init __rmem_check_for_overlap(void)
280{
281 int i;
282
283 if (reserved_mem_count < 2)
284 return;
285
286 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
287 __rmem_cmp, NULL);
288 for (i = 0; i < reserved_mem_count - 1; i++) {
289 struct reserved_mem *this, *next;
290
291 this = &reserved_mem[i];
292 next = &reserved_mem[i + 1];
293
294 if (this->base + this->size > next->base) {
295 phys_addr_t this_end, next_end;
296
297 this_end = this->base + this->size;
298 next_end = next->base + next->size;
299 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
300 this->name, &this->base, &this_end,
301 next->name, &next->base, &next_end);
302 }
303 }
304}
305
306/**
307 * fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
308 */
309void __init fdt_init_reserved_mem(void)
310{
311 int i;
312
313 /* check for overlapping reserved regions */
314 __rmem_check_for_overlap();
315
316 for (i = 0; i < reserved_mem_count; i++) {
317 struct reserved_mem *rmem = &reserved_mem[i];
318 unsigned long node = rmem->fdt_node;
319 int len;
320 const __be32 *prop;
321 int err = 0;
322 bool nomap;
323
324 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
325 prop = of_get_flat_dt_prop(node, "phandle", &len);
326 if (!prop)
327 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
328 if (prop)
329 rmem->phandle = of_read_number(prop, len/4);
330
331 if (rmem->size == 0)
332 err = __reserved_mem_alloc_size(node, rmem->name,
333 &rmem->base, &rmem->size);
334 if (err == 0) {
335 err = __reserved_mem_init_node(rmem);
336 if (err != 0 && err != -ENOENT) {
337 pr_info("node %s compatible matching fail\n",
338 rmem->name);
339 if (nomap)
340 memblock_clear_nomap(rmem->base, rmem->size);
341 else
342 memblock_phys_free(rmem->base,
343 rmem->size);
344 } else {
345 phys_addr_t end = rmem->base + rmem->size - 1;
346 bool reusable =
347 (of_get_flat_dt_prop(node, "reusable", NULL)) != NULL;
348
349 pr_info("%pa..%pa (%lu KiB) %s %s %s\n",
350 &rmem->base, &end, (unsigned long)(rmem->size / SZ_1K),
351 nomap ? "nomap" : "map",
352 reusable ? "reusable" : "non-reusable",
353 rmem->name ? rmem->name : "unknown");
354 }
355 }
356 }
357}
358
359static inline struct reserved_mem *__find_rmem(struct device_node *node)
360{
361 unsigned int i;
362
363 if (!node->phandle)
364 return NULL;
365
366 for (i = 0; i < reserved_mem_count; i++)
367 if (reserved_mem[i].phandle == node->phandle)
368 return &reserved_mem[i];
369 return NULL;
370}
371
372struct rmem_assigned_device {
373 struct device *dev;
374 struct reserved_mem *rmem;
375 struct list_head list;
376};
377
378static LIST_HEAD(of_rmem_assigned_device_list);
379static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
380
381/**
382 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
383 * given device
384 * @dev: Pointer to the device to configure
385 * @np: Pointer to the device_node with 'reserved-memory' property
386 * @idx: Index of selected region
387 *
388 * This function assigns respective DMA-mapping operations based on reserved
389 * memory region specified by 'memory-region' property in @np node to the @dev
390 * device. When driver needs to use more than one reserved memory region, it
391 * should allocate child devices and initialize regions by name for each of
392 * child device.
393 *
394 * Returns error code or zero on success.
395 */
396int of_reserved_mem_device_init_by_idx(struct device *dev,
397 struct device_node *np, int idx)
398{
399 struct rmem_assigned_device *rd;
400 struct device_node *target;
401 struct reserved_mem *rmem;
402 int ret;
403
404 if (!np || !dev)
405 return -EINVAL;
406
407 target = of_parse_phandle(np, "memory-region", idx);
408 if (!target)
409 return -ENODEV;
410
411 if (!of_device_is_available(target)) {
412 of_node_put(target);
413 return 0;
414 }
415
416 rmem = __find_rmem(target);
417 of_node_put(target);
418
419 if (!rmem || !rmem->ops || !rmem->ops->device_init)
420 return -EINVAL;
421
422 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
423 if (!rd)
424 return -ENOMEM;
425
426 ret = rmem->ops->device_init(rmem, dev);
427 if (ret == 0) {
428 rd->dev = dev;
429 rd->rmem = rmem;
430
431 mutex_lock(&of_rmem_assigned_device_mutex);
432 list_add(&rd->list, &of_rmem_assigned_device_list);
433 mutex_unlock(&of_rmem_assigned_device_mutex);
434
435 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
436 } else {
437 kfree(rd);
438 }
439
440 return ret;
441}
442EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
443
444/**
445 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
446 * to given device
447 * @dev: pointer to the device to configure
448 * @np: pointer to the device node with 'memory-region' property
449 * @name: name of the selected memory region
450 *
451 * Returns: 0 on success or a negative error-code on failure.
452 */
453int of_reserved_mem_device_init_by_name(struct device *dev,
454 struct device_node *np,
455 const char *name)
456{
457 int idx = of_property_match_string(np, "memory-region-names", name);
458
459 return of_reserved_mem_device_init_by_idx(dev, np, idx);
460}
461EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
462
463/**
464 * of_reserved_mem_device_release() - release reserved memory device structures
465 * @dev: Pointer to the device to deconfigure
466 *
467 * This function releases structures allocated for memory region handling for
468 * the given device.
469 */
470void of_reserved_mem_device_release(struct device *dev)
471{
472 struct rmem_assigned_device *rd, *tmp;
473 LIST_HEAD(release_list);
474
475 mutex_lock(&of_rmem_assigned_device_mutex);
476 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
477 if (rd->dev == dev)
478 list_move_tail(&rd->list, &release_list);
479 }
480 mutex_unlock(&of_rmem_assigned_device_mutex);
481
482 list_for_each_entry_safe(rd, tmp, &release_list, list) {
483 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
484 rd->rmem->ops->device_release(rd->rmem, dev);
485
486 kfree(rd);
487 }
488}
489EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
490
491/**
492 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
493 * @np: node pointer of the desired reserved-memory region
494 *
495 * This function allows drivers to acquire a reference to the reserved_mem
496 * struct based on a device node handle.
497 *
498 * Returns a reserved_mem reference, or NULL on error.
499 */
500struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
501{
502 const char *name;
503 int i;
504
505 if (!np->full_name)
506 return NULL;
507
508 name = kbasename(np->full_name);
509 for (i = 0; i < reserved_mem_count; i++)
510 if (!strcmp(reserved_mem[i].name, name))
511 return &reserved_mem[i];
512
513 return NULL;
514}
515EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);