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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_size() - allocate reserved memory described by
82 * 'size', 'alignment' and 'alloc-ranges' properties.
83 */
84static 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;
90 int len;
91 const __be32 *prop;
92 bool 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)) {
100 pr_err("invalid size property in '%s' node.\n", uname);
101 return -EINVAL;
102 }
103 size = dt_mem_next_cell(dt_root_size_cells, &prop);
104
105 prop = of_get_flat_dt_prop(node, "alignment", &len);
106 if (prop) {
107 if (len != dt_root_addr_cells * sizeof(__be32)) {
108 pr_err("invalid alignment property in '%s' node.\n",
109 uname);
110 return -EINVAL;
111 }
112 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
113 }
114
115 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
116
117 /* Need adjust the alignment to satisfy the CMA requirement */
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)
121 && !nomap)
122 align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
123
124 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
125 if (prop) {
126
127 if (len % t_len != 0) {
128 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
129 uname);
130 return -EINVAL;
131 }
132
133 base = 0;
134
135 while (len > 0) {
136 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
137 end = start + dt_mem_next_cell(dt_root_size_cells,
138 &prop);
139
140 ret = early_init_dt_alloc_reserved_memory_arch(size,
141 align, start, end, nomap, &base);
142 if (ret == 0) {
143 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
144 uname, &base,
145 (unsigned long)(size / SZ_1M));
146 break;
147 }
148 len -= t_len;
149 }
150
151 } else {
152 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
153 0, 0, nomap, &base);
154 if (ret == 0)
155 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
156 uname, &base, (unsigned long)(size / SZ_1M));
157 }
158
159 if (base == 0) {
160 pr_err("failed to allocate memory for node '%s': size %lu MiB\n",
161 uname, (unsigned long)(size / SZ_1M));
162 return -ENOMEM;
163 }
164
165 *res_base = base;
166 *res_size = size;
167
168 return 0;
169}
170
171static const struct of_device_id __rmem_of_table_sentinel
172 __used __section("__reservedmem_of_table_end");
173
174/*
175 * __reserved_mem_init_node() - call region specific reserved memory init code
176 */
177static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
178{
179 extern const struct of_device_id __reservedmem_of_table[];
180 const struct of_device_id *i;
181 int ret = -ENOENT;
182
183 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
184 reservedmem_of_init_fn initfn = i->data;
185 const char *compat = i->compatible;
186
187 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
188 continue;
189
190 ret = initfn(rmem);
191 if (ret == 0) {
192 pr_info("initialized node %s, compatible id %s\n",
193 rmem->name, compat);
194 break;
195 }
196 }
197 return ret;
198}
199
200static int __init __rmem_cmp(const void *a, const void *b)
201{
202 const struct reserved_mem *ra = a, *rb = b;
203
204 if (ra->base < rb->base)
205 return -1;
206
207 if (ra->base > rb->base)
208 return 1;
209
210 /*
211 * Put the dynamic allocations (address == 0, size == 0) before static
212 * allocations at address 0x0 so that overlap detection works
213 * correctly.
214 */
215 if (ra->size < rb->size)
216 return -1;
217 if (ra->size > rb->size)
218 return 1;
219
220 return 0;
221}
222
223static void __init __rmem_check_for_overlap(void)
224{
225 int i;
226
227 if (reserved_mem_count < 2)
228 return;
229
230 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
231 __rmem_cmp, NULL);
232 for (i = 0; i < reserved_mem_count - 1; i++) {
233 struct reserved_mem *this, *next;
234
235 this = &reserved_mem[i];
236 next = &reserved_mem[i + 1];
237
238 if (this->base + this->size > next->base) {
239 phys_addr_t this_end, next_end;
240
241 this_end = this->base + this->size;
242 next_end = next->base + next->size;
243 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
244 this->name, &this->base, &this_end,
245 next->name, &next->base, &next_end);
246 }
247 }
248}
249
250/**
251 * fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
252 */
253void __init fdt_init_reserved_mem(void)
254{
255 int i;
256
257 /* check for overlapping reserved regions */
258 __rmem_check_for_overlap();
259
260 for (i = 0; i < reserved_mem_count; i++) {
261 struct reserved_mem *rmem = &reserved_mem[i];
262 unsigned long node = rmem->fdt_node;
263 int len;
264 const __be32 *prop;
265 int err = 0;
266 bool nomap;
267
268 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
269 prop = of_get_flat_dt_prop(node, "phandle", &len);
270 if (!prop)
271 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
272 if (prop)
273 rmem->phandle = of_read_number(prop, len/4);
274
275 if (rmem->size == 0)
276 err = __reserved_mem_alloc_size(node, rmem->name,
277 &rmem->base, &rmem->size);
278 if (err == 0) {
279 err = __reserved_mem_init_node(rmem);
280 if (err != 0 && err != -ENOENT) {
281 pr_info("node %s compatible matching fail\n",
282 rmem->name);
283 if (nomap)
284 memblock_clear_nomap(rmem->base, rmem->size);
285 else
286 memblock_phys_free(rmem->base,
287 rmem->size);
288 }
289 }
290 }
291}
292
293static inline struct reserved_mem *__find_rmem(struct device_node *node)
294{
295 unsigned int i;
296
297 if (!node->phandle)
298 return NULL;
299
300 for (i = 0; i < reserved_mem_count; i++)
301 if (reserved_mem[i].phandle == node->phandle)
302 return &reserved_mem[i];
303 return NULL;
304}
305
306struct rmem_assigned_device {
307 struct device *dev;
308 struct reserved_mem *rmem;
309 struct list_head list;
310};
311
312static LIST_HEAD(of_rmem_assigned_device_list);
313static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
314
315/**
316 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
317 * given device
318 * @dev: Pointer to the device to configure
319 * @np: Pointer to the device_node with 'reserved-memory' property
320 * @idx: Index of selected region
321 *
322 * This function assigns respective DMA-mapping operations based on reserved
323 * memory region specified by 'memory-region' property in @np node to the @dev
324 * device. When driver needs to use more than one reserved memory region, it
325 * should allocate child devices and initialize regions by name for each of
326 * child device.
327 *
328 * Returns error code or zero on success.
329 */
330int of_reserved_mem_device_init_by_idx(struct device *dev,
331 struct device_node *np, int idx)
332{
333 struct rmem_assigned_device *rd;
334 struct device_node *target;
335 struct reserved_mem *rmem;
336 int ret;
337
338 if (!np || !dev)
339 return -EINVAL;
340
341 target = of_parse_phandle(np, "memory-region", idx);
342 if (!target)
343 return -ENODEV;
344
345 if (!of_device_is_available(target)) {
346 of_node_put(target);
347 return 0;
348 }
349
350 rmem = __find_rmem(target);
351 of_node_put(target);
352
353 if (!rmem || !rmem->ops || !rmem->ops->device_init)
354 return -EINVAL;
355
356 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
357 if (!rd)
358 return -ENOMEM;
359
360 ret = rmem->ops->device_init(rmem, dev);
361 if (ret == 0) {
362 rd->dev = dev;
363 rd->rmem = rmem;
364
365 mutex_lock(&of_rmem_assigned_device_mutex);
366 list_add(&rd->list, &of_rmem_assigned_device_list);
367 mutex_unlock(&of_rmem_assigned_device_mutex);
368
369 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
370 } else {
371 kfree(rd);
372 }
373
374 return ret;
375}
376EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
377
378/**
379 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
380 * to given device
381 * @dev: pointer to the device to configure
382 * @np: pointer to the device node with 'memory-region' property
383 * @name: name of the selected memory region
384 *
385 * Returns: 0 on success or a negative error-code on failure.
386 */
387int of_reserved_mem_device_init_by_name(struct device *dev,
388 struct device_node *np,
389 const char *name)
390{
391 int idx = of_property_match_string(np, "memory-region-names", name);
392
393 return of_reserved_mem_device_init_by_idx(dev, np, idx);
394}
395EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
396
397/**
398 * of_reserved_mem_device_release() - release reserved memory device structures
399 * @dev: Pointer to the device to deconfigure
400 *
401 * This function releases structures allocated for memory region handling for
402 * the given device.
403 */
404void of_reserved_mem_device_release(struct device *dev)
405{
406 struct rmem_assigned_device *rd, *tmp;
407 LIST_HEAD(release_list);
408
409 mutex_lock(&of_rmem_assigned_device_mutex);
410 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
411 if (rd->dev == dev)
412 list_move_tail(&rd->list, &release_list);
413 }
414 mutex_unlock(&of_rmem_assigned_device_mutex);
415
416 list_for_each_entry_safe(rd, tmp, &release_list, list) {
417 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
418 rd->rmem->ops->device_release(rd->rmem, dev);
419
420 kfree(rd);
421 }
422}
423EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
424
425/**
426 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
427 * @np: node pointer of the desired reserved-memory region
428 *
429 * This function allows drivers to acquire a reference to the reserved_mem
430 * struct based on a device node handle.
431 *
432 * Returns a reserved_mem reference, or NULL on error.
433 */
434struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
435{
436 const char *name;
437 int i;
438
439 if (!np->full_name)
440 return NULL;
441
442 name = kbasename(np->full_name);
443 for (i = 0; i < reserved_mem_count; i++)
444 if (!strcmp(reserved_mem[i].name, name))
445 return &reserved_mem[i];
446
447 return NULL;
448}
449EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);
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
25#define MAX_RESERVED_REGIONS 64
26static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
27static int reserved_mem_count;
28
29static int __init 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{
33 phys_addr_t base;
34
35 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
36 align = !align ? SMP_CACHE_BYTES : align;
37 base = memblock_find_in_range(start, end, size, align);
38 if (!base)
39 return -ENOMEM;
40
41 *res_base = base;
42 if (nomap)
43 return memblock_remove(base, size);
44
45 return memblock_reserve(base, size);
46}
47
48/**
49 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
50 */
51void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
52 phys_addr_t base, phys_addr_t size)
53{
54 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
55
56 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
57 pr_err("not enough space for all defined regions.\n");
58 return;
59 }
60
61 rmem->fdt_node = node;
62 rmem->name = uname;
63 rmem->base = base;
64 rmem->size = size;
65
66 reserved_mem_count++;
67 return;
68}
69
70/**
71 * __reserved_mem_alloc_size() - allocate reserved memory described by
72 * 'size', 'alignment' and 'alloc-ranges' properties.
73 */
74static int __init __reserved_mem_alloc_size(unsigned long node,
75 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
76{
77 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
78 phys_addr_t start = 0, end = 0;
79 phys_addr_t base = 0, align = 0, size;
80 int len;
81 const __be32 *prop;
82 bool nomap;
83 int ret;
84
85 prop = of_get_flat_dt_prop(node, "size", &len);
86 if (!prop)
87 return -EINVAL;
88
89 if (len != dt_root_size_cells * sizeof(__be32)) {
90 pr_err("invalid size property in '%s' node.\n", uname);
91 return -EINVAL;
92 }
93 size = dt_mem_next_cell(dt_root_size_cells, &prop);
94
95 prop = of_get_flat_dt_prop(node, "alignment", &len);
96 if (prop) {
97 if (len != dt_root_addr_cells * sizeof(__be32)) {
98 pr_err("invalid alignment property in '%s' node.\n",
99 uname);
100 return -EINVAL;
101 }
102 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
103 }
104
105 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
106
107 /* Need adjust the alignment to satisfy the CMA requirement */
108 if (IS_ENABLED(CONFIG_CMA)
109 && of_flat_dt_is_compatible(node, "shared-dma-pool")
110 && of_get_flat_dt_prop(node, "reusable", NULL)
111 && !nomap) {
112 unsigned long order =
113 max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
114
115 align = max(align, (phys_addr_t)PAGE_SIZE << order);
116 }
117
118 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
119 if (prop) {
120
121 if (len % t_len != 0) {
122 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
123 uname);
124 return -EINVAL;
125 }
126
127 base = 0;
128
129 while (len > 0) {
130 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
131 end = start + dt_mem_next_cell(dt_root_size_cells,
132 &prop);
133
134 ret = early_init_dt_alloc_reserved_memory_arch(size,
135 align, start, end, nomap, &base);
136 if (ret == 0) {
137 pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
138 uname, &base,
139 (unsigned long)size / SZ_1M);
140 break;
141 }
142 len -= t_len;
143 }
144
145 } else {
146 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
147 0, 0, nomap, &base);
148 if (ret == 0)
149 pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
150 uname, &base, (unsigned long)size / SZ_1M);
151 }
152
153 if (base == 0) {
154 pr_info("failed to allocate memory for node '%s'\n", uname);
155 return -ENOMEM;
156 }
157
158 *res_base = base;
159 *res_size = size;
160
161 return 0;
162}
163
164static const struct of_device_id __rmem_of_table_sentinel
165 __used __section(__reservedmem_of_table_end);
166
167/**
168 * __reserved_mem_init_node() - call region specific reserved memory init code
169 */
170static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
171{
172 extern const struct of_device_id __reservedmem_of_table[];
173 const struct of_device_id *i;
174 int ret = -ENOENT;
175
176 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
177 reservedmem_of_init_fn initfn = i->data;
178 const char *compat = i->compatible;
179
180 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
181 continue;
182
183 ret = initfn(rmem);
184 if (ret == 0) {
185 pr_info("initialized node %s, compatible id %s\n",
186 rmem->name, compat);
187 break;
188 }
189 }
190 return ret;
191}
192
193static int __init __rmem_cmp(const void *a, const void *b)
194{
195 const struct reserved_mem *ra = a, *rb = b;
196
197 if (ra->base < rb->base)
198 return -1;
199
200 if (ra->base > rb->base)
201 return 1;
202
203 return 0;
204}
205
206static void __init __rmem_check_for_overlap(void)
207{
208 int i;
209
210 if (reserved_mem_count < 2)
211 return;
212
213 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
214 __rmem_cmp, NULL);
215 for (i = 0; i < reserved_mem_count - 1; i++) {
216 struct reserved_mem *this, *next;
217
218 this = &reserved_mem[i];
219 next = &reserved_mem[i + 1];
220 if (!(this->base && next->base))
221 continue;
222 if (this->base + this->size > next->base) {
223 phys_addr_t this_end, next_end;
224
225 this_end = this->base + this->size;
226 next_end = next->base + next->size;
227 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
228 this->name, &this->base, &this_end,
229 next->name, &next->base, &next_end);
230 }
231 }
232}
233
234/**
235 * fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
236 */
237void __init fdt_init_reserved_mem(void)
238{
239 int i;
240
241 /* check for overlapping reserved regions */
242 __rmem_check_for_overlap();
243
244 for (i = 0; i < reserved_mem_count; i++) {
245 struct reserved_mem *rmem = &reserved_mem[i];
246 unsigned long node = rmem->fdt_node;
247 int len;
248 const __be32 *prop;
249 int err = 0;
250 bool nomap;
251
252 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
253 prop = of_get_flat_dt_prop(node, "phandle", &len);
254 if (!prop)
255 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
256 if (prop)
257 rmem->phandle = of_read_number(prop, len/4);
258
259 if (rmem->size == 0)
260 err = __reserved_mem_alloc_size(node, rmem->name,
261 &rmem->base, &rmem->size);
262 if (err == 0) {
263 err = __reserved_mem_init_node(rmem);
264 if (err != 0 && err != -ENOENT) {
265 pr_info("node %s compatible matching fail\n",
266 rmem->name);
267 memblock_free(rmem->base, rmem->size);
268 if (nomap)
269 memblock_add(rmem->base, rmem->size);
270 }
271 }
272 }
273}
274
275static inline struct reserved_mem *__find_rmem(struct device_node *node)
276{
277 unsigned int i;
278
279 if (!node->phandle)
280 return NULL;
281
282 for (i = 0; i < reserved_mem_count; i++)
283 if (reserved_mem[i].phandle == node->phandle)
284 return &reserved_mem[i];
285 return NULL;
286}
287
288struct rmem_assigned_device {
289 struct device *dev;
290 struct reserved_mem *rmem;
291 struct list_head list;
292};
293
294static LIST_HEAD(of_rmem_assigned_device_list);
295static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
296
297/**
298 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
299 * given device
300 * @dev: Pointer to the device to configure
301 * @np: Pointer to the device_node with 'reserved-memory' property
302 * @idx: Index of selected region
303 *
304 * This function assigns respective DMA-mapping operations based on reserved
305 * memory region specified by 'memory-region' property in @np node to the @dev
306 * device. When driver needs to use more than one reserved memory region, it
307 * should allocate child devices and initialize regions by name for each of
308 * child device.
309 *
310 * Returns error code or zero on success.
311 */
312int of_reserved_mem_device_init_by_idx(struct device *dev,
313 struct device_node *np, int idx)
314{
315 struct rmem_assigned_device *rd;
316 struct device_node *target;
317 struct reserved_mem *rmem;
318 int ret;
319
320 if (!np || !dev)
321 return -EINVAL;
322
323 target = of_parse_phandle(np, "memory-region", idx);
324 if (!target)
325 return -ENODEV;
326
327 if (!of_device_is_available(target)) {
328 of_node_put(target);
329 return 0;
330 }
331
332 rmem = __find_rmem(target);
333 of_node_put(target);
334
335 if (!rmem || !rmem->ops || !rmem->ops->device_init)
336 return -EINVAL;
337
338 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
339 if (!rd)
340 return -ENOMEM;
341
342 ret = rmem->ops->device_init(rmem, dev);
343 if (ret == 0) {
344 rd->dev = dev;
345 rd->rmem = rmem;
346
347 mutex_lock(&of_rmem_assigned_device_mutex);
348 list_add(&rd->list, &of_rmem_assigned_device_list);
349 mutex_unlock(&of_rmem_assigned_device_mutex);
350
351 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
352 } else {
353 kfree(rd);
354 }
355
356 return ret;
357}
358EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
359
360/**
361 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
362 * to given device
363 * @dev: pointer to the device to configure
364 * @np: pointer to the device node with 'memory-region' property
365 * @name: name of the selected memory region
366 *
367 * Returns: 0 on success or a negative error-code on failure.
368 */
369int of_reserved_mem_device_init_by_name(struct device *dev,
370 struct device_node *np,
371 const char *name)
372{
373 int idx = of_property_match_string(np, "memory-region-names", name);
374
375 return of_reserved_mem_device_init_by_idx(dev, np, idx);
376}
377EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
378
379/**
380 * of_reserved_mem_device_release() - release reserved memory device structures
381 * @dev: Pointer to the device to deconfigure
382 *
383 * This function releases structures allocated for memory region handling for
384 * the given device.
385 */
386void of_reserved_mem_device_release(struct device *dev)
387{
388 struct rmem_assigned_device *rd, *tmp;
389 LIST_HEAD(release_list);
390
391 mutex_lock(&of_rmem_assigned_device_mutex);
392 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
393 if (rd->dev == dev)
394 list_move_tail(&rd->list, &release_list);
395 }
396 mutex_unlock(&of_rmem_assigned_device_mutex);
397
398 list_for_each_entry_safe(rd, tmp, &release_list, list) {
399 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
400 rd->rmem->ops->device_release(rd->rmem, dev);
401
402 kfree(rd);
403 }
404}
405EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
406
407/**
408 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
409 * @np: node pointer of the desired reserved-memory region
410 *
411 * This function allows drivers to acquire a reference to the reserved_mem
412 * struct based on a device node handle.
413 *
414 * Returns a reserved_mem reference, or NULL on error.
415 */
416struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
417{
418 const char *name;
419 int i;
420
421 if (!np->full_name)
422 return NULL;
423
424 name = kbasename(np->full_name);
425 for (i = 0; i < reserved_mem_count; i++)
426 if (!strcmp(reserved_mem[i].name, name))
427 return &reserved_mem[i];
428
429 return NULL;
430}
431EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);