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/ioport.h>
16 #include <linux/libfdt.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 #include <linux/slab.h>
25 #include <linux/memblock.h>
26 #include <linux/kmemleak.h>
27 #include <linux/cma.h>
28 #include <linux/dma-map-ops.h>
29
30 #include "of_private.h"
31
32 static struct reserved_mem reserved_mem_array[MAX_RESERVED_REGIONS] __initdata;
33 static struct reserved_mem *reserved_mem __refdata = reserved_mem_array;
34 static int total_reserved_mem_cnt = MAX_RESERVED_REGIONS;
35 static int reserved_mem_count;
36
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)37 static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
38 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
39 phys_addr_t *res_base)
40 {
41 phys_addr_t base;
42 int err = 0;
43
44 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
45 align = !align ? SMP_CACHE_BYTES : align;
46 base = memblock_phys_alloc_range(size, align, start, end);
47 if (!base)
48 return -ENOMEM;
49
50 *res_base = base;
51 if (nomap) {
52 err = memblock_mark_nomap(base, size);
53 if (err)
54 memblock_phys_free(base, size);
55 }
56
57 if (!err)
58 kmemleak_ignore_phys(base);
59
60 return err;
61 }
62
63 /*
64 * alloc_reserved_mem_array() - allocate memory for the reserved_mem
65 * array using memblock
66 *
67 * This function is used to allocate memory for the reserved_mem
68 * array according to the total number of reserved memory regions
69 * defined in the DT.
70 * After the new array is allocated, the information stored in
71 * the initial static array is copied over to this new array and
72 * the new array is used from this point on.
73 */
alloc_reserved_mem_array(void)74 static void __init alloc_reserved_mem_array(void)
75 {
76 struct reserved_mem *new_array;
77 size_t alloc_size, copy_size, memset_size;
78
79 alloc_size = array_size(total_reserved_mem_cnt, sizeof(*new_array));
80 if (alloc_size == SIZE_MAX) {
81 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -EOVERFLOW);
82 return;
83 }
84
85 new_array = memblock_alloc(alloc_size, SMP_CACHE_BYTES);
86 if (!new_array) {
87 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -ENOMEM);
88 return;
89 }
90
91 copy_size = array_size(reserved_mem_count, sizeof(*new_array));
92 if (copy_size == SIZE_MAX) {
93 memblock_free(new_array, alloc_size);
94 total_reserved_mem_cnt = MAX_RESERVED_REGIONS;
95 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -EOVERFLOW);
96 return;
97 }
98
99 memset_size = alloc_size - copy_size;
100
101 memcpy(new_array, reserved_mem, copy_size);
102 memset(new_array + reserved_mem_count, 0, memset_size);
103
104 reserved_mem = new_array;
105 }
106
107 static void __init fdt_init_reserved_mem_node(struct reserved_mem *rmem);
108 /*
109 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
110 */
fdt_reserved_mem_save_node(unsigned long node,const char * uname,phys_addr_t base,phys_addr_t size)111 static void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
112 phys_addr_t base, phys_addr_t size)
113 {
114 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
115
116 if (reserved_mem_count == total_reserved_mem_cnt) {
117 pr_err("not enough space for all defined regions.\n");
118 return;
119 }
120
121 rmem->fdt_node = node;
122 rmem->name = uname;
123 rmem->base = base;
124 rmem->size = size;
125
126 /* Call the region specific initialization function */
127 fdt_init_reserved_mem_node(rmem);
128
129 reserved_mem_count++;
130 return;
131 }
132
early_init_dt_reserve_memory(phys_addr_t base,phys_addr_t size,bool nomap)133 static int __init early_init_dt_reserve_memory(phys_addr_t base,
134 phys_addr_t size, bool nomap)
135 {
136 if (nomap) {
137 /*
138 * If the memory is already reserved (by another region), we
139 * should not allow it to be marked nomap, but don't worry
140 * if the region isn't memory as it won't be mapped.
141 */
142 if (memblock_overlaps_region(&memblock.memory, base, size) &&
143 memblock_is_region_reserved(base, size))
144 return -EBUSY;
145
146 return memblock_mark_nomap(base, size);
147 }
148 return memblock_reserve(base, size);
149 }
150
151 /*
152 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
153 */
__reserved_mem_reserve_reg(unsigned long node,const char * uname)154 static int __init __reserved_mem_reserve_reg(unsigned long node,
155 const char *uname)
156 {
157 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
158 phys_addr_t base, size;
159 int len;
160 const __be32 *prop;
161 bool nomap;
162
163 prop = of_get_flat_dt_prop(node, "reg", &len);
164 if (!prop)
165 return -ENOENT;
166
167 if (len && len % t_len != 0) {
168 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
169 uname);
170 return -EINVAL;
171 }
172
173 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
174
175 while (len >= t_len) {
176 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
177 size = dt_mem_next_cell(dt_root_size_cells, &prop);
178
179 if (size && early_init_dt_reserve_memory(base, size, nomap) == 0) {
180 /* Architecture specific contiguous memory fixup. */
181 if (of_flat_dt_is_compatible(node, "shared-dma-pool") &&
182 of_get_flat_dt_prop(node, "reusable", NULL))
183 dma_contiguous_early_fixup(base, size);
184 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
185 uname, &base, (unsigned long)(size / SZ_1M));
186 } else {
187 pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
188 uname, &base, (unsigned long)(size / SZ_1M));
189 }
190
191 len -= t_len;
192 }
193 return 0;
194 }
195
196 /*
197 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
198 * in /reserved-memory matches the values supported by the current implementation,
199 * also check if ranges property has been provided
200 */
__reserved_mem_check_root(unsigned long node)201 static int __init __reserved_mem_check_root(unsigned long node)
202 {
203 const __be32 *prop;
204
205 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
206 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
207 return -EINVAL;
208
209 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
210 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
211 return -EINVAL;
212
213 prop = of_get_flat_dt_prop(node, "ranges", NULL);
214 if (!prop)
215 return -EINVAL;
216 return 0;
217 }
218
219 static void __init __rmem_check_for_overlap(void);
220
221 /**
222 * fdt_scan_reserved_mem_reg_nodes() - Store info for the "reg" defined
223 * reserved memory regions.
224 *
225 * This function is used to scan through the DT and store the
226 * information for the reserved memory regions that are defined using
227 * the "reg" property. The region node number, name, base address, and
228 * size are all stored in the reserved_mem array by calling the
229 * fdt_reserved_mem_save_node() function.
230 */
fdt_scan_reserved_mem_reg_nodes(void)231 void __init fdt_scan_reserved_mem_reg_nodes(void)
232 {
233 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
234 const void *fdt = initial_boot_params;
235 phys_addr_t base, size;
236 const __be32 *prop;
237 int node, child;
238 int len;
239
240 if (!fdt)
241 return;
242
243 node = fdt_path_offset(fdt, "/reserved-memory");
244 if (node < 0) {
245 pr_info("Reserved memory: No reserved-memory node in the DT\n");
246 return;
247 }
248
249 /* Attempt dynamic allocation of a new reserved_mem array */
250 alloc_reserved_mem_array();
251
252 if (__reserved_mem_check_root(node)) {
253 pr_err("Reserved memory: unsupported node format, ignoring\n");
254 return;
255 }
256
257 fdt_for_each_subnode(child, fdt, node) {
258 const char *uname;
259
260 prop = of_get_flat_dt_prop(child, "reg", &len);
261 if (!prop)
262 continue;
263 if (!of_fdt_device_is_available(fdt, child))
264 continue;
265
266 uname = fdt_get_name(fdt, child, NULL);
267 if (len && len % t_len != 0) {
268 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
269 uname);
270 continue;
271 }
272
273 if (len > t_len)
274 pr_warn("%s() ignores %d regions in node '%s'\n",
275 __func__, len / t_len - 1, uname);
276
277 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
278 size = dt_mem_next_cell(dt_root_size_cells, &prop);
279
280 if (size)
281 fdt_reserved_mem_save_node(child, uname, base, size);
282 }
283
284 /* check for overlapping reserved regions */
285 __rmem_check_for_overlap();
286 }
287
288 static int __init __reserved_mem_alloc_size(unsigned long node, const char *uname);
289
290 /*
291 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
292 */
fdt_scan_reserved_mem(void)293 int __init fdt_scan_reserved_mem(void)
294 {
295 int node, child;
296 int dynamic_nodes_cnt = 0, count = 0;
297 int dynamic_nodes[MAX_RESERVED_REGIONS];
298 const void *fdt = initial_boot_params;
299
300 node = fdt_path_offset(fdt, "/reserved-memory");
301 if (node < 0)
302 return -ENODEV;
303
304 if (__reserved_mem_check_root(node) != 0) {
305 pr_err("Reserved memory: unsupported node format, ignoring\n");
306 return -EINVAL;
307 }
308
309 fdt_for_each_subnode(child, fdt, node) {
310 const char *uname;
311 int err;
312
313 if (!of_fdt_device_is_available(fdt, child))
314 continue;
315
316 uname = fdt_get_name(fdt, child, NULL);
317
318 err = __reserved_mem_reserve_reg(child, uname);
319 if (!err)
320 count++;
321 /*
322 * Save the nodes for the dynamically-placed regions
323 * into an array which will be used for allocation right
324 * after all the statically-placed regions are reserved
325 * or marked as no-map. This is done to avoid dynamically
326 * allocating from one of the statically-placed regions.
327 */
328 if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL)) {
329 dynamic_nodes[dynamic_nodes_cnt] = child;
330 dynamic_nodes_cnt++;
331 }
332 }
333 for (int i = 0; i < dynamic_nodes_cnt; i++) {
334 const char *uname;
335 int err;
336
337 child = dynamic_nodes[i];
338 uname = fdt_get_name(fdt, child, NULL);
339 err = __reserved_mem_alloc_size(child, uname);
340 if (!err)
341 count++;
342 }
343 total_reserved_mem_cnt = count;
344 return 0;
345 }
346
347 /*
348 * __reserved_mem_alloc_in_range() - allocate reserved memory described with
349 * 'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing
350 * reserved regions to keep the reserved memory contiguous if possible.
351 */
__reserved_mem_alloc_in_range(phys_addr_t size,phys_addr_t align,phys_addr_t start,phys_addr_t end,bool nomap,phys_addr_t * res_base)352 static int __init __reserved_mem_alloc_in_range(phys_addr_t size,
353 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
354 phys_addr_t *res_base)
355 {
356 bool prev_bottom_up = memblock_bottom_up();
357 bool bottom_up = false, top_down = false;
358 int ret, i;
359
360 for (i = 0; i < reserved_mem_count; i++) {
361 struct reserved_mem *rmem = &reserved_mem[i];
362
363 /* Skip regions that were not reserved yet */
364 if (rmem->size == 0)
365 continue;
366
367 /*
368 * If range starts next to an existing reservation, use bottom-up:
369 * |....RRRR................RRRRRRRR..............|
370 * --RRRR------
371 */
372 if (start >= rmem->base && start <= (rmem->base + rmem->size))
373 bottom_up = true;
374
375 /*
376 * If range ends next to an existing reservation, use top-down:
377 * |....RRRR................RRRRRRRR..............|
378 * -------RRRR-----
379 */
380 if (end >= rmem->base && end <= (rmem->base + rmem->size))
381 top_down = true;
382 }
383
384 /* Change setting only if either bottom-up or top-down was selected */
385 if (bottom_up != top_down)
386 memblock_set_bottom_up(bottom_up);
387
388 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
389 start, end, nomap, res_base);
390
391 /* Restore old setting if needed */
392 if (bottom_up != top_down)
393 memblock_set_bottom_up(prev_bottom_up);
394
395 return ret;
396 }
397
398 /*
399 * __reserved_mem_alloc_size() - allocate reserved memory described by
400 * 'size', 'alignment' and 'alloc-ranges' properties.
401 */
__reserved_mem_alloc_size(unsigned long node,const char * uname)402 static int __init __reserved_mem_alloc_size(unsigned long node, const char *uname)
403 {
404 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
405 phys_addr_t start = 0, end = 0;
406 phys_addr_t base = 0, align = 0, size;
407 int len;
408 const __be32 *prop;
409 bool nomap;
410 int ret;
411
412 prop = of_get_flat_dt_prop(node, "size", &len);
413 if (!prop)
414 return -EINVAL;
415
416 if (len != dt_root_size_cells * sizeof(__be32)) {
417 pr_err("invalid size property in '%s' node.\n", uname);
418 return -EINVAL;
419 }
420 size = dt_mem_next_cell(dt_root_size_cells, &prop);
421
422 prop = of_get_flat_dt_prop(node, "alignment", &len);
423 if (prop) {
424 if (len != dt_root_addr_cells * sizeof(__be32)) {
425 pr_err("invalid alignment property in '%s' node.\n",
426 uname);
427 return -EINVAL;
428 }
429 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
430 }
431
432 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
433
434 /* Need adjust the alignment to satisfy the CMA requirement */
435 if (IS_ENABLED(CONFIG_CMA)
436 && of_flat_dt_is_compatible(node, "shared-dma-pool")
437 && of_get_flat_dt_prop(node, "reusable", NULL)
438 && !nomap)
439 align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
440
441 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
442 if (prop) {
443
444 if (len % t_len != 0) {
445 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
446 uname);
447 return -EINVAL;
448 }
449
450 while (len > 0) {
451 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
452 end = start + dt_mem_next_cell(dt_root_size_cells,
453 &prop);
454
455 base = 0;
456 ret = __reserved_mem_alloc_in_range(size, align,
457 start, end, nomap, &base);
458 if (ret == 0) {
459 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
460 uname, &base,
461 (unsigned long)(size / SZ_1M));
462 break;
463 }
464 len -= t_len;
465 }
466
467 } else {
468 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
469 0, 0, nomap, &base);
470 if (ret == 0)
471 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
472 uname, &base, (unsigned long)(size / SZ_1M));
473 }
474
475 if (base == 0) {
476 pr_err("failed to allocate memory for node '%s': size %lu MiB\n",
477 uname, (unsigned long)(size / SZ_1M));
478 return -ENOMEM;
479 }
480 /* Architecture specific contiguous memory fixup. */
481 if (of_flat_dt_is_compatible(node, "shared-dma-pool") &&
482 of_get_flat_dt_prop(node, "reusable", NULL))
483 dma_contiguous_early_fixup(base, size);
484 /* Save region in the reserved_mem array */
485 fdt_reserved_mem_save_node(node, uname, base, size);
486 return 0;
487 }
488
489 static const struct of_device_id __rmem_of_table_sentinel
490 __used __section("__reservedmem_of_table_end");
491
492 /*
493 * __reserved_mem_init_node() - call region specific reserved memory init code
494 */
__reserved_mem_init_node(struct reserved_mem * rmem)495 static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
496 {
497 extern const struct of_device_id __reservedmem_of_table[];
498 const struct of_device_id *i;
499 int ret = -ENOENT;
500
501 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
502 reservedmem_of_init_fn initfn = i->data;
503 const char *compat = i->compatible;
504
505 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
506 continue;
507
508 ret = initfn(rmem);
509 if (ret == 0) {
510 pr_info("initialized node %s, compatible id %s\n",
511 rmem->name, compat);
512 break;
513 }
514 }
515 return ret;
516 }
517
__rmem_cmp(const void * a,const void * b)518 static int __init __rmem_cmp(const void *a, const void *b)
519 {
520 const struct reserved_mem *ra = a, *rb = b;
521
522 if (ra->base < rb->base)
523 return -1;
524
525 if (ra->base > rb->base)
526 return 1;
527
528 /*
529 * Put the dynamic allocations (address == 0, size == 0) before static
530 * allocations at address 0x0 so that overlap detection works
531 * correctly.
532 */
533 if (ra->size < rb->size)
534 return -1;
535 if (ra->size > rb->size)
536 return 1;
537
538 if (ra->fdt_node < rb->fdt_node)
539 return -1;
540 if (ra->fdt_node > rb->fdt_node)
541 return 1;
542
543 return 0;
544 }
545
__rmem_check_for_overlap(void)546 static void __init __rmem_check_for_overlap(void)
547 {
548 int i;
549
550 if (reserved_mem_count < 2)
551 return;
552
553 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
554 __rmem_cmp, NULL);
555 for (i = 0; i < reserved_mem_count - 1; i++) {
556 struct reserved_mem *this, *next;
557
558 this = &reserved_mem[i];
559 next = &reserved_mem[i + 1];
560
561 if (this->base + this->size > next->base) {
562 phys_addr_t this_end, next_end;
563
564 this_end = this->base + this->size;
565 next_end = next->base + next->size;
566 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
567 this->name, &this->base, &this_end,
568 next->name, &next->base, &next_end);
569 }
570 }
571 }
572
573 /**
574 * fdt_init_reserved_mem_node() - Initialize a reserved memory region
575 * @rmem: reserved_mem struct of the memory region to be initialized.
576 *
577 * This function is used to call the region specific initialization
578 * function for a reserved memory region.
579 */
fdt_init_reserved_mem_node(struct reserved_mem * rmem)580 static void __init fdt_init_reserved_mem_node(struct reserved_mem *rmem)
581 {
582 unsigned long node = rmem->fdt_node;
583 int err = 0;
584 bool nomap;
585
586 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
587
588 err = __reserved_mem_init_node(rmem);
589 if (err != 0 && err != -ENOENT) {
590 pr_info("node %s compatible matching fail\n", rmem->name);
591 if (nomap)
592 memblock_clear_nomap(rmem->base, rmem->size);
593 else
594 memblock_phys_free(rmem->base, rmem->size);
595 } else {
596 phys_addr_t end = rmem->base + rmem->size - 1;
597 bool reusable =
598 (of_get_flat_dt_prop(node, "reusable", NULL)) != NULL;
599
600 pr_info("%pa..%pa (%lu KiB) %s %s %s\n",
601 &rmem->base, &end, (unsigned long)(rmem->size / SZ_1K),
602 nomap ? "nomap" : "map",
603 reusable ? "reusable" : "non-reusable",
604 rmem->name ? rmem->name : "unknown");
605 }
606 }
607
608 struct rmem_assigned_device {
609 struct device *dev;
610 struct reserved_mem *rmem;
611 struct list_head list;
612 };
613
614 static LIST_HEAD(of_rmem_assigned_device_list);
615 static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
616
617 /**
618 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
619 * given device
620 * @dev: Pointer to the device to configure
621 * @np: Pointer to the device_node with 'reserved-memory' property
622 * @idx: Index of selected region
623 *
624 * This function assigns respective DMA-mapping operations based on reserved
625 * memory region specified by 'memory-region' property in @np node to the @dev
626 * device. When driver needs to use more than one reserved memory region, it
627 * should allocate child devices and initialize regions by name for each of
628 * child device.
629 *
630 * Returns error code or zero on success.
631 */
of_reserved_mem_device_init_by_idx(struct device * dev,struct device_node * np,int idx)632 int of_reserved_mem_device_init_by_idx(struct device *dev,
633 struct device_node *np, int idx)
634 {
635 struct rmem_assigned_device *rd;
636 struct device_node *target;
637 struct reserved_mem *rmem;
638 int ret;
639
640 if (!np || !dev)
641 return -EINVAL;
642
643 target = of_parse_phandle(np, "memory-region", idx);
644 if (!target)
645 return -ENODEV;
646
647 if (!of_device_is_available(target)) {
648 of_node_put(target);
649 return 0;
650 }
651
652 rmem = of_reserved_mem_lookup(target);
653 of_node_put(target);
654
655 if (!rmem || !rmem->ops || !rmem->ops->device_init)
656 return -EINVAL;
657
658 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
659 if (!rd)
660 return -ENOMEM;
661
662 ret = rmem->ops->device_init(rmem, dev);
663 if (ret == 0) {
664 rd->dev = dev;
665 rd->rmem = rmem;
666
667 mutex_lock(&of_rmem_assigned_device_mutex);
668 list_add(&rd->list, &of_rmem_assigned_device_list);
669 mutex_unlock(&of_rmem_assigned_device_mutex);
670
671 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
672 } else {
673 kfree(rd);
674 }
675
676 return ret;
677 }
678 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
679
680 /**
681 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
682 * to given device
683 * @dev: pointer to the device to configure
684 * @np: pointer to the device node with 'memory-region' property
685 * @name: name of the selected memory region
686 *
687 * Returns: 0 on success or a negative error-code on failure.
688 */
of_reserved_mem_device_init_by_name(struct device * dev,struct device_node * np,const char * name)689 int of_reserved_mem_device_init_by_name(struct device *dev,
690 struct device_node *np,
691 const char *name)
692 {
693 int idx = of_property_match_string(np, "memory-region-names", name);
694
695 return of_reserved_mem_device_init_by_idx(dev, np, idx);
696 }
697 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
698
699 /**
700 * of_reserved_mem_device_release() - release reserved memory device structures
701 * @dev: Pointer to the device to deconfigure
702 *
703 * This function releases structures allocated for memory region handling for
704 * the given device.
705 */
of_reserved_mem_device_release(struct device * dev)706 void of_reserved_mem_device_release(struct device *dev)
707 {
708 struct rmem_assigned_device *rd, *tmp;
709 LIST_HEAD(release_list);
710
711 mutex_lock(&of_rmem_assigned_device_mutex);
712 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
713 if (rd->dev == dev)
714 list_move_tail(&rd->list, &release_list);
715 }
716 mutex_unlock(&of_rmem_assigned_device_mutex);
717
718 list_for_each_entry_safe(rd, tmp, &release_list, list) {
719 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
720 rd->rmem->ops->device_release(rd->rmem, dev);
721
722 kfree(rd);
723 }
724 }
725 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
726
727 /**
728 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
729 * @np: node pointer of the desired reserved-memory region
730 *
731 * This function allows drivers to acquire a reference to the reserved_mem
732 * struct based on a device node handle.
733 *
734 * Returns a reserved_mem reference, or NULL on error.
735 */
of_reserved_mem_lookup(struct device_node * np)736 struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
737 {
738 const char *name;
739 int i;
740
741 if (!np->full_name)
742 return NULL;
743
744 name = kbasename(np->full_name);
745 for (i = 0; i < reserved_mem_count; i++)
746 if (!strcmp(reserved_mem[i].name, name))
747 return &reserved_mem[i];
748
749 return NULL;
750 }
751 EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);
752
753 /**
754 * of_reserved_mem_region_to_resource() - Get a reserved memory region as a resource
755 * @np: node containing 'memory-region' property
756 * @idx: index of 'memory-region' property to lookup
757 * @res: Pointer to a struct resource to fill in with reserved region
758 *
759 * This function allows drivers to lookup a node's 'memory-region' property
760 * entries by index and return a struct resource for the entry.
761 *
762 * Returns 0 on success with @res filled in. Returns -ENODEV if 'memory-region'
763 * is missing or unavailable, -EINVAL for any other error.
764 */
of_reserved_mem_region_to_resource(const struct device_node * np,unsigned int idx,struct resource * res)765 int of_reserved_mem_region_to_resource(const struct device_node *np,
766 unsigned int idx, struct resource *res)
767 {
768 struct reserved_mem *rmem;
769
770 if (!np)
771 return -EINVAL;
772
773 struct device_node __free(device_node) *target = of_parse_phandle(np, "memory-region", idx);
774 if (!target || !of_device_is_available(target))
775 return -ENODEV;
776
777 rmem = of_reserved_mem_lookup(target);
778 if (!rmem)
779 return -EINVAL;
780
781 resource_set_range(res, rmem->base, rmem->size);
782 res->flags = IORESOURCE_MEM;
783 res->name = rmem->name;
784 return 0;
785 }
786 EXPORT_SYMBOL_GPL(of_reserved_mem_region_to_resource);
787
788 /**
789 * of_reserved_mem_region_to_resource_byname() - Get a reserved memory region as a resource
790 * @np: node containing 'memory-region' property
791 * @name: name of 'memory-region' property entry to lookup
792 * @res: Pointer to a struct resource to fill in with reserved region
793 *
794 * This function allows drivers to lookup a node's 'memory-region' property
795 * entries by name and return a struct resource for the entry.
796 *
797 * Returns 0 on success with @res filled in, or a negative error-code on
798 * failure.
799 */
of_reserved_mem_region_to_resource_byname(const struct device_node * np,const char * name,struct resource * res)800 int of_reserved_mem_region_to_resource_byname(const struct device_node *np,
801 const char *name,
802 struct resource *res)
803 {
804 int idx;
805
806 if (!name)
807 return -EINVAL;
808
809 idx = of_property_match_string(np, "memory-region-names", name);
810 if (idx < 0)
811 return idx;
812
813 return of_reserved_mem_region_to_resource(np, idx, res);
814 }
815 EXPORT_SYMBOL_GPL(of_reserved_mem_region_to_resource_byname);
816
817 /**
818 * of_reserved_mem_region_count() - Return the number of 'memory-region' entries
819 * @np: node containing 'memory-region' property
820 *
821 * This function allows drivers to retrieve the number of entries for a node's
822 * 'memory-region' property.
823 *
824 * Returns the number of entries on success, or negative error code on a
825 * malformed property.
826 */
of_reserved_mem_region_count(const struct device_node * np)827 int of_reserved_mem_region_count(const struct device_node *np)
828 {
829 return of_count_phandle_with_args(np, "memory-region", NULL);
830 }
831 EXPORT_SYMBOL_GPL(of_reserved_mem_region_count);
832