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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/libfdt.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_platform.h>
19#include <linux/mm.h>
20#include <linux/sizes.h>
21#include <linux/of_reserved_mem.h>
22#include <linux/sort.h>
23#include <linux/slab.h>
24#include <linux/memblock.h>
25#include <linux/kmemleak.h>
26#include <linux/cma.h>
27
28#include "of_private.h"
29
30static struct reserved_mem reserved_mem_array[MAX_RESERVED_REGIONS] __initdata;
31static struct reserved_mem *reserved_mem __refdata = reserved_mem_array;
32static int total_reserved_mem_cnt = MAX_RESERVED_REGIONS;
33static int reserved_mem_count;
34
35static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
36 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
37 phys_addr_t *res_base)
38{
39 phys_addr_t base;
40 int err = 0;
41
42 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
43 align = !align ? SMP_CACHE_BYTES : align;
44 base = memblock_phys_alloc_range(size, align, start, end);
45 if (!base)
46 return -ENOMEM;
47
48 *res_base = base;
49 if (nomap) {
50 err = memblock_mark_nomap(base, size);
51 if (err)
52 memblock_phys_free(base, size);
53 }
54
55 if (!err)
56 kmemleak_ignore_phys(base);
57
58 return err;
59}
60
61/*
62 * alloc_reserved_mem_array() - allocate memory for the reserved_mem
63 * array using memblock
64 *
65 * This function is used to allocate memory for the reserved_mem
66 * array according to the total number of reserved memory regions
67 * defined in the DT.
68 * After the new array is allocated, the information stored in
69 * the initial static array is copied over to this new array and
70 * the new array is used from this point on.
71 */
72static void __init alloc_reserved_mem_array(void)
73{
74 struct reserved_mem *new_array;
75 size_t alloc_size, copy_size, memset_size;
76
77 alloc_size = array_size(total_reserved_mem_cnt, sizeof(*new_array));
78 if (alloc_size == SIZE_MAX) {
79 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -EOVERFLOW);
80 return;
81 }
82
83 new_array = memblock_alloc(alloc_size, SMP_CACHE_BYTES);
84 if (!new_array) {
85 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -ENOMEM);
86 return;
87 }
88
89 copy_size = array_size(reserved_mem_count, sizeof(*new_array));
90 if (copy_size == SIZE_MAX) {
91 memblock_free(new_array, alloc_size);
92 total_reserved_mem_cnt = MAX_RESERVED_REGIONS;
93 pr_err("Failed to allocate memory for reserved_mem array with err: %d", -EOVERFLOW);
94 return;
95 }
96
97 memset_size = alloc_size - copy_size;
98
99 memcpy(new_array, reserved_mem, copy_size);
100 memset(new_array + reserved_mem_count, 0, memset_size);
101
102 reserved_mem = new_array;
103}
104
105static void __init fdt_init_reserved_mem_node(struct reserved_mem *rmem);
106/*
107 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
108 */
109static void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
110 phys_addr_t base, phys_addr_t size)
111{
112 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
113
114 if (reserved_mem_count == total_reserved_mem_cnt) {
115 pr_err("not enough space for all defined regions.\n");
116 return;
117 }
118
119 rmem->fdt_node = node;
120 rmem->name = uname;
121 rmem->base = base;
122 rmem->size = size;
123
124 /* Call the region specific initialization function */
125 fdt_init_reserved_mem_node(rmem);
126
127 reserved_mem_count++;
128 return;
129}
130
131static int __init early_init_dt_reserve_memory(phys_addr_t base,
132 phys_addr_t size, bool nomap)
133{
134 if (nomap) {
135 /*
136 * If the memory is already reserved (by another region), we
137 * should not allow it to be marked nomap, but don't worry
138 * if the region isn't memory as it won't be mapped.
139 */
140 if (memblock_overlaps_region(&memblock.memory, base, size) &&
141 memblock_is_region_reserved(base, size))
142 return -EBUSY;
143
144 return memblock_mark_nomap(base, size);
145 }
146 return memblock_reserve(base, size);
147}
148
149/*
150 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
151 */
152static int __init __reserved_mem_reserve_reg(unsigned long node,
153 const char *uname)
154{
155 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
156 phys_addr_t base, size;
157 int len;
158 const __be32 *prop;
159 bool nomap;
160
161 prop = of_get_flat_dt_prop(node, "reg", &len);
162 if (!prop)
163 return -ENOENT;
164
165 if (len && len % t_len != 0) {
166 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
167 uname);
168 return -EINVAL;
169 }
170
171 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
172
173 while (len >= t_len) {
174 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
175 size = dt_mem_next_cell(dt_root_size_cells, &prop);
176
177 if (size &&
178 early_init_dt_reserve_memory(base, size, nomap) == 0)
179 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
180 uname, &base, (unsigned long)(size / SZ_1M));
181 else
182 pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
183 uname, &base, (unsigned long)(size / SZ_1M));
184
185 len -= t_len;
186 }
187 return 0;
188}
189
190/*
191 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
192 * in /reserved-memory matches the values supported by the current implementation,
193 * also check if ranges property has been provided
194 */
195static int __init __reserved_mem_check_root(unsigned long node)
196{
197 const __be32 *prop;
198
199 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
200 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
201 return -EINVAL;
202
203 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
204 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
205 return -EINVAL;
206
207 prop = of_get_flat_dt_prop(node, "ranges", NULL);
208 if (!prop)
209 return -EINVAL;
210 return 0;
211}
212
213static void __init __rmem_check_for_overlap(void);
214
215/**
216 * fdt_scan_reserved_mem_reg_nodes() - Store info for the "reg" defined
217 * reserved memory regions.
218 *
219 * This function is used to scan through the DT and store the
220 * information for the reserved memory regions that are defined using
221 * the "reg" property. The region node number, name, base address, and
222 * size are all stored in the reserved_mem array by calling the
223 * fdt_reserved_mem_save_node() function.
224 */
225void __init fdt_scan_reserved_mem_reg_nodes(void)
226{
227 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
228 const void *fdt = initial_boot_params;
229 phys_addr_t base, size;
230 const __be32 *prop;
231 int node, child;
232 int len;
233
234 if (!fdt)
235 return;
236
237 node = fdt_path_offset(fdt, "/reserved-memory");
238 if (node < 0) {
239 pr_info("Reserved memory: No reserved-memory node in the DT\n");
240 return;
241 }
242
243 /* Attempt dynamic allocation of a new reserved_mem array */
244 alloc_reserved_mem_array();
245
246 if (__reserved_mem_check_root(node)) {
247 pr_err("Reserved memory: unsupported node format, ignoring\n");
248 return;
249 }
250
251 fdt_for_each_subnode(child, fdt, node) {
252 const char *uname;
253
254 prop = of_get_flat_dt_prop(child, "reg", &len);
255 if (!prop)
256 continue;
257 if (!of_fdt_device_is_available(fdt, child))
258 continue;
259
260 uname = fdt_get_name(fdt, child, NULL);
261 if (len && len % t_len != 0) {
262 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
263 uname);
264 continue;
265 }
266
267 if (len > t_len)
268 pr_warn("%s() ignores %d regions in node '%s'\n",
269 __func__, len / t_len - 1, uname);
270
271 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
272 size = dt_mem_next_cell(dt_root_size_cells, &prop);
273
274 if (size)
275 fdt_reserved_mem_save_node(child, uname, base, size);
276 }
277
278 /* check for overlapping reserved regions */
279 __rmem_check_for_overlap();
280}
281
282static int __init __reserved_mem_alloc_size(unsigned long node, const char *uname);
283
284/*
285 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
286 */
287int __init fdt_scan_reserved_mem(void)
288{
289 int node, child;
290 int dynamic_nodes_cnt = 0, count = 0;
291 int dynamic_nodes[MAX_RESERVED_REGIONS];
292 const void *fdt = initial_boot_params;
293
294 node = fdt_path_offset(fdt, "/reserved-memory");
295 if (node < 0)
296 return -ENODEV;
297
298 if (__reserved_mem_check_root(node) != 0) {
299 pr_err("Reserved memory: unsupported node format, ignoring\n");
300 return -EINVAL;
301 }
302
303 fdt_for_each_subnode(child, fdt, node) {
304 const char *uname;
305 int err;
306
307 if (!of_fdt_device_is_available(fdt, child))
308 continue;
309
310 uname = fdt_get_name(fdt, child, NULL);
311
312 err = __reserved_mem_reserve_reg(child, uname);
313 if (!err)
314 count++;
315 /*
316 * Save the nodes for the dynamically-placed regions
317 * into an array which will be used for allocation right
318 * after all the statically-placed regions are reserved
319 * or marked as no-map. This is done to avoid dynamically
320 * allocating from one of the statically-placed regions.
321 */
322 if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL)) {
323 dynamic_nodes[dynamic_nodes_cnt] = child;
324 dynamic_nodes_cnt++;
325 }
326 }
327 for (int i = 0; i < dynamic_nodes_cnt; i++) {
328 const char *uname;
329 int err;
330
331 child = dynamic_nodes[i];
332 uname = fdt_get_name(fdt, child, NULL);
333 err = __reserved_mem_alloc_size(child, uname);
334 if (!err)
335 count++;
336 }
337 total_reserved_mem_cnt = count;
338 return 0;
339}
340
341/*
342 * __reserved_mem_alloc_in_range() - allocate reserved memory described with
343 * 'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing
344 * reserved regions to keep the reserved memory contiguous if possible.
345 */
346static int __init __reserved_mem_alloc_in_range(phys_addr_t size,
347 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
348 phys_addr_t *res_base)
349{
350 bool prev_bottom_up = memblock_bottom_up();
351 bool bottom_up = false, top_down = false;
352 int ret, i;
353
354 for (i = 0; i < reserved_mem_count; i++) {
355 struct reserved_mem *rmem = &reserved_mem[i];
356
357 /* Skip regions that were not reserved yet */
358 if (rmem->size == 0)
359 continue;
360
361 /*
362 * If range starts next to an existing reservation, use bottom-up:
363 * |....RRRR................RRRRRRRR..............|
364 * --RRRR------
365 */
366 if (start >= rmem->base && start <= (rmem->base + rmem->size))
367 bottom_up = true;
368
369 /*
370 * If range ends next to an existing reservation, use top-down:
371 * |....RRRR................RRRRRRRR..............|
372 * -------RRRR-----
373 */
374 if (end >= rmem->base && end <= (rmem->base + rmem->size))
375 top_down = true;
376 }
377
378 /* Change setting only if either bottom-up or top-down was selected */
379 if (bottom_up != top_down)
380 memblock_set_bottom_up(bottom_up);
381
382 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
383 start, end, nomap, res_base);
384
385 /* Restore old setting if needed */
386 if (bottom_up != top_down)
387 memblock_set_bottom_up(prev_bottom_up);
388
389 return ret;
390}
391
392/*
393 * __reserved_mem_alloc_size() - allocate reserved memory described by
394 * 'size', 'alignment' and 'alloc-ranges' properties.
395 */
396static int __init __reserved_mem_alloc_size(unsigned long node, const char *uname)
397{
398 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
399 phys_addr_t start = 0, end = 0;
400 phys_addr_t base = 0, align = 0, size;
401 int len;
402 const __be32 *prop;
403 bool nomap;
404 int ret;
405
406 prop = of_get_flat_dt_prop(node, "size", &len);
407 if (!prop)
408 return -EINVAL;
409
410 if (len != dt_root_size_cells * sizeof(__be32)) {
411 pr_err("invalid size property in '%s' node.\n", uname);
412 return -EINVAL;
413 }
414 size = dt_mem_next_cell(dt_root_size_cells, &prop);
415
416 prop = of_get_flat_dt_prop(node, "alignment", &len);
417 if (prop) {
418 if (len != dt_root_addr_cells * sizeof(__be32)) {
419 pr_err("invalid alignment property in '%s' node.\n",
420 uname);
421 return -EINVAL;
422 }
423 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
424 }
425
426 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
427
428 /* Need adjust the alignment to satisfy the CMA requirement */
429 if (IS_ENABLED(CONFIG_CMA)
430 && of_flat_dt_is_compatible(node, "shared-dma-pool")
431 && of_get_flat_dt_prop(node, "reusable", NULL)
432 && !nomap)
433 align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
434
435 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
436 if (prop) {
437
438 if (len % t_len != 0) {
439 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
440 uname);
441 return -EINVAL;
442 }
443
444 base = 0;
445
446 while (len > 0) {
447 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
448 end = start + dt_mem_next_cell(dt_root_size_cells,
449 &prop);
450
451 ret = __reserved_mem_alloc_in_range(size, align,
452 start, end, nomap, &base);
453 if (ret == 0) {
454 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
455 uname, &base,
456 (unsigned long)(size / SZ_1M));
457 break;
458 }
459 len -= t_len;
460 }
461
462 } else {
463 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
464 0, 0, nomap, &base);
465 if (ret == 0)
466 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
467 uname, &base, (unsigned long)(size / SZ_1M));
468 }
469
470 if (base == 0) {
471 pr_err("failed to allocate memory for node '%s': size %lu MiB\n",
472 uname, (unsigned long)(size / SZ_1M));
473 return -ENOMEM;
474 }
475
476 /* Save region in the reserved_mem array */
477 fdt_reserved_mem_save_node(node, uname, base, size);
478 return 0;
479}
480
481static const struct of_device_id __rmem_of_table_sentinel
482 __used __section("__reservedmem_of_table_end");
483
484/*
485 * __reserved_mem_init_node() - call region specific reserved memory init code
486 */
487static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
488{
489 extern const struct of_device_id __reservedmem_of_table[];
490 const struct of_device_id *i;
491 int ret = -ENOENT;
492
493 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
494 reservedmem_of_init_fn initfn = i->data;
495 const char *compat = i->compatible;
496
497 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
498 continue;
499
500 ret = initfn(rmem);
501 if (ret == 0) {
502 pr_info("initialized node %s, compatible id %s\n",
503 rmem->name, compat);
504 break;
505 }
506 }
507 return ret;
508}
509
510static int __init __rmem_cmp(const void *a, const void *b)
511{
512 const struct reserved_mem *ra = a, *rb = b;
513
514 if (ra->base < rb->base)
515 return -1;
516
517 if (ra->base > rb->base)
518 return 1;
519
520 /*
521 * Put the dynamic allocations (address == 0, size == 0) before static
522 * allocations at address 0x0 so that overlap detection works
523 * correctly.
524 */
525 if (ra->size < rb->size)
526 return -1;
527 if (ra->size > rb->size)
528 return 1;
529
530 if (ra->fdt_node < rb->fdt_node)
531 return -1;
532 if (ra->fdt_node > rb->fdt_node)
533 return 1;
534
535 return 0;
536}
537
538static void __init __rmem_check_for_overlap(void)
539{
540 int i;
541
542 if (reserved_mem_count < 2)
543 return;
544
545 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
546 __rmem_cmp, NULL);
547 for (i = 0; i < reserved_mem_count - 1; i++) {
548 struct reserved_mem *this, *next;
549
550 this = &reserved_mem[i];
551 next = &reserved_mem[i + 1];
552
553 if (this->base + this->size > next->base) {
554 phys_addr_t this_end, next_end;
555
556 this_end = this->base + this->size;
557 next_end = next->base + next->size;
558 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
559 this->name, &this->base, &this_end,
560 next->name, &next->base, &next_end);
561 }
562 }
563}
564
565/**
566 * fdt_init_reserved_mem_node() - Initialize a reserved memory region
567 * @rmem: reserved_mem struct of the memory region to be initialized.
568 *
569 * This function is used to call the region specific initialization
570 * function for a reserved memory region.
571 */
572static void __init fdt_init_reserved_mem_node(struct reserved_mem *rmem)
573{
574 unsigned long node = rmem->fdt_node;
575 int err = 0;
576 bool nomap;
577
578 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
579
580 err = __reserved_mem_init_node(rmem);
581 if (err != 0 && err != -ENOENT) {
582 pr_info("node %s compatible matching fail\n", rmem->name);
583 if (nomap)
584 memblock_clear_nomap(rmem->base, rmem->size);
585 else
586 memblock_phys_free(rmem->base, rmem->size);
587 } else {
588 phys_addr_t end = rmem->base + rmem->size - 1;
589 bool reusable =
590 (of_get_flat_dt_prop(node, "reusable", NULL)) != NULL;
591
592 pr_info("%pa..%pa (%lu KiB) %s %s %s\n",
593 &rmem->base, &end, (unsigned long)(rmem->size / SZ_1K),
594 nomap ? "nomap" : "map",
595 reusable ? "reusable" : "non-reusable",
596 rmem->name ? rmem->name : "unknown");
597 }
598}
599
600struct rmem_assigned_device {
601 struct device *dev;
602 struct reserved_mem *rmem;
603 struct list_head list;
604};
605
606static LIST_HEAD(of_rmem_assigned_device_list);
607static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
608
609/**
610 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
611 * given device
612 * @dev: Pointer to the device to configure
613 * @np: Pointer to the device_node with 'reserved-memory' property
614 * @idx: Index of selected region
615 *
616 * This function assigns respective DMA-mapping operations based on reserved
617 * memory region specified by 'memory-region' property in @np node to the @dev
618 * device. When driver needs to use more than one reserved memory region, it
619 * should allocate child devices and initialize regions by name for each of
620 * child device.
621 *
622 * Returns error code or zero on success.
623 */
624int of_reserved_mem_device_init_by_idx(struct device *dev,
625 struct device_node *np, int idx)
626{
627 struct rmem_assigned_device *rd;
628 struct device_node *target;
629 struct reserved_mem *rmem;
630 int ret;
631
632 if (!np || !dev)
633 return -EINVAL;
634
635 target = of_parse_phandle(np, "memory-region", idx);
636 if (!target)
637 return -ENODEV;
638
639 if (!of_device_is_available(target)) {
640 of_node_put(target);
641 return 0;
642 }
643
644 rmem = of_reserved_mem_lookup(target);
645 of_node_put(target);
646
647 if (!rmem || !rmem->ops || !rmem->ops->device_init)
648 return -EINVAL;
649
650 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
651 if (!rd)
652 return -ENOMEM;
653
654 ret = rmem->ops->device_init(rmem, dev);
655 if (ret == 0) {
656 rd->dev = dev;
657 rd->rmem = rmem;
658
659 mutex_lock(&of_rmem_assigned_device_mutex);
660 list_add(&rd->list, &of_rmem_assigned_device_list);
661 mutex_unlock(&of_rmem_assigned_device_mutex);
662
663 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
664 } else {
665 kfree(rd);
666 }
667
668 return ret;
669}
670EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
671
672/**
673 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
674 * to given device
675 * @dev: pointer to the device to configure
676 * @np: pointer to the device node with 'memory-region' property
677 * @name: name of the selected memory region
678 *
679 * Returns: 0 on success or a negative error-code on failure.
680 */
681int of_reserved_mem_device_init_by_name(struct device *dev,
682 struct device_node *np,
683 const char *name)
684{
685 int idx = of_property_match_string(np, "memory-region-names", name);
686
687 return of_reserved_mem_device_init_by_idx(dev, np, idx);
688}
689EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
690
691/**
692 * of_reserved_mem_device_release() - release reserved memory device structures
693 * @dev: Pointer to the device to deconfigure
694 *
695 * This function releases structures allocated for memory region handling for
696 * the given device.
697 */
698void of_reserved_mem_device_release(struct device *dev)
699{
700 struct rmem_assigned_device *rd, *tmp;
701 LIST_HEAD(release_list);
702
703 mutex_lock(&of_rmem_assigned_device_mutex);
704 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
705 if (rd->dev == dev)
706 list_move_tail(&rd->list, &release_list);
707 }
708 mutex_unlock(&of_rmem_assigned_device_mutex);
709
710 list_for_each_entry_safe(rd, tmp, &release_list, list) {
711 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
712 rd->rmem->ops->device_release(rd->rmem, dev);
713
714 kfree(rd);
715 }
716}
717EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
718
719/**
720 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
721 * @np: node pointer of the desired reserved-memory region
722 *
723 * This function allows drivers to acquire a reference to the reserved_mem
724 * struct based on a device node handle.
725 *
726 * Returns a reserved_mem reference, or NULL on error.
727 */
728struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
729{
730 const char *name;
731 int i;
732
733 if (!np->full_name)
734 return NULL;
735
736 name = kbasename(np->full_name);
737 for (i = 0; i < reserved_mem_count; i++)
738 if (!strcmp(reserved_mem[i].name, name))
739 return &reserved_mem[i];
740
741 return NULL;
742}
743EXPORT_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/libfdt.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_platform.h>
19#include <linux/mm.h>
20#include <linux/sizes.h>
21#include <linux/of_reserved_mem.h>
22#include <linux/sort.h>
23#include <linux/slab.h>
24#include <linux/memblock.h>
25#include <linux/kmemleak.h>
26#include <linux/cma.h>
27
28#include "of_private.h"
29
30#define MAX_RESERVED_REGIONS 64
31static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
32static int reserved_mem_count;
33
34static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
35 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
36 phys_addr_t *res_base)
37{
38 phys_addr_t base;
39 int err = 0;
40
41 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
42 align = !align ? SMP_CACHE_BYTES : align;
43 base = memblock_phys_alloc_range(size, align, start, end);
44 if (!base)
45 return -ENOMEM;
46
47 *res_base = base;
48 if (nomap) {
49 err = memblock_mark_nomap(base, size);
50 if (err)
51 memblock_phys_free(base, size);
52 }
53
54 kmemleak_ignore_phys(base);
55
56 return err;
57}
58
59/*
60 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
61 */
62static void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
63 phys_addr_t base, phys_addr_t size)
64{
65 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
66
67 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
68 pr_err("not enough space for all defined regions.\n");
69 return;
70 }
71
72 rmem->fdt_node = node;
73 rmem->name = uname;
74 rmem->base = base;
75 rmem->size = size;
76
77 reserved_mem_count++;
78 return;
79}
80
81static int __init early_init_dt_reserve_memory(phys_addr_t base,
82 phys_addr_t size, bool nomap)
83{
84 if (nomap) {
85 /*
86 * If the memory is already reserved (by another region), we
87 * should not allow it to be marked nomap, but don't worry
88 * if the region isn't memory as it won't be mapped.
89 */
90 if (memblock_overlaps_region(&memblock.memory, base, size) &&
91 memblock_is_region_reserved(base, size))
92 return -EBUSY;
93
94 return memblock_mark_nomap(base, size);
95 }
96 return memblock_reserve(base, size);
97}
98
99/*
100 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
101 */
102static int __init __reserved_mem_reserve_reg(unsigned long node,
103 const char *uname)
104{
105 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
106 phys_addr_t base, size;
107 int len;
108 const __be32 *prop;
109 int first = 1;
110 bool nomap;
111
112 prop = of_get_flat_dt_prop(node, "reg", &len);
113 if (!prop)
114 return -ENOENT;
115
116 if (len && len % t_len != 0) {
117 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
118 uname);
119 return -EINVAL;
120 }
121
122 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
123
124 while (len >= t_len) {
125 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
126 size = dt_mem_next_cell(dt_root_size_cells, &prop);
127
128 if (size &&
129 early_init_dt_reserve_memory(base, size, nomap) == 0)
130 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
131 uname, &base, (unsigned long)(size / SZ_1M));
132 else
133 pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
134 uname, &base, (unsigned long)(size / SZ_1M));
135
136 len -= t_len;
137 if (first) {
138 fdt_reserved_mem_save_node(node, uname, base, size);
139 first = 0;
140 }
141 }
142 return 0;
143}
144
145/*
146 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
147 * in /reserved-memory matches the values supported by the current implementation,
148 * also check if ranges property has been provided
149 */
150static int __init __reserved_mem_check_root(unsigned long node)
151{
152 const __be32 *prop;
153
154 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
155 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
156 return -EINVAL;
157
158 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
159 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
160 return -EINVAL;
161
162 prop = of_get_flat_dt_prop(node, "ranges", NULL);
163 if (!prop)
164 return -EINVAL;
165 return 0;
166}
167
168/*
169 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
170 */
171int __init fdt_scan_reserved_mem(void)
172{
173 int node, child;
174 const void *fdt = initial_boot_params;
175
176 node = fdt_path_offset(fdt, "/reserved-memory");
177 if (node < 0)
178 return -ENODEV;
179
180 if (__reserved_mem_check_root(node) != 0) {
181 pr_err("Reserved memory: unsupported node format, ignoring\n");
182 return -EINVAL;
183 }
184
185 fdt_for_each_subnode(child, fdt, node) {
186 const char *uname;
187 int err;
188
189 if (!of_fdt_device_is_available(fdt, child))
190 continue;
191
192 uname = fdt_get_name(fdt, child, NULL);
193
194 err = __reserved_mem_reserve_reg(child, uname);
195 if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))
196 fdt_reserved_mem_save_node(child, uname, 0, 0);
197 }
198 return 0;
199}
200
201/*
202 * __reserved_mem_alloc_in_range() - allocate reserved memory described with
203 * 'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing
204 * reserved regions to keep the reserved memory contiguous if possible.
205 */
206static int __init __reserved_mem_alloc_in_range(phys_addr_t size,
207 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
208 phys_addr_t *res_base)
209{
210 bool prev_bottom_up = memblock_bottom_up();
211 bool bottom_up = false, top_down = false;
212 int ret, i;
213
214 for (i = 0; i < reserved_mem_count; i++) {
215 struct reserved_mem *rmem = &reserved_mem[i];
216
217 /* Skip regions that were not reserved yet */
218 if (rmem->size == 0)
219 continue;
220
221 /*
222 * If range starts next to an existing reservation, use bottom-up:
223 * |....RRRR................RRRRRRRR..............|
224 * --RRRR------
225 */
226 if (start >= rmem->base && start <= (rmem->base + rmem->size))
227 bottom_up = true;
228
229 /*
230 * If range ends next to an existing reservation, use top-down:
231 * |....RRRR................RRRRRRRR..............|
232 * -------RRRR-----
233 */
234 if (end >= rmem->base && end <= (rmem->base + rmem->size))
235 top_down = true;
236 }
237
238 /* Change setting only if either bottom-up or top-down was selected */
239 if (bottom_up != top_down)
240 memblock_set_bottom_up(bottom_up);
241
242 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
243 start, end, nomap, res_base);
244
245 /* Restore old setting if needed */
246 if (bottom_up != top_down)
247 memblock_set_bottom_up(prev_bottom_up);
248
249 return ret;
250}
251
252/*
253 * __reserved_mem_alloc_size() - allocate reserved memory described by
254 * 'size', 'alignment' and 'alloc-ranges' properties.
255 */
256static int __init __reserved_mem_alloc_size(unsigned long node,
257 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
258{
259 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
260 phys_addr_t start = 0, end = 0;
261 phys_addr_t base = 0, align = 0, size;
262 int len;
263 const __be32 *prop;
264 bool nomap;
265 int ret;
266
267 prop = of_get_flat_dt_prop(node, "size", &len);
268 if (!prop)
269 return -EINVAL;
270
271 if (len != dt_root_size_cells * sizeof(__be32)) {
272 pr_err("invalid size property in '%s' node.\n", uname);
273 return -EINVAL;
274 }
275 size = dt_mem_next_cell(dt_root_size_cells, &prop);
276
277 prop = of_get_flat_dt_prop(node, "alignment", &len);
278 if (prop) {
279 if (len != dt_root_addr_cells * sizeof(__be32)) {
280 pr_err("invalid alignment property in '%s' node.\n",
281 uname);
282 return -EINVAL;
283 }
284 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
285 }
286
287 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
288
289 /* Need adjust the alignment to satisfy the CMA requirement */
290 if (IS_ENABLED(CONFIG_CMA)
291 && of_flat_dt_is_compatible(node, "shared-dma-pool")
292 && of_get_flat_dt_prop(node, "reusable", NULL)
293 && !nomap)
294 align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
295
296 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
297 if (prop) {
298
299 if (len % t_len != 0) {
300 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
301 uname);
302 return -EINVAL;
303 }
304
305 base = 0;
306
307 while (len > 0) {
308 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
309 end = start + dt_mem_next_cell(dt_root_size_cells,
310 &prop);
311
312 ret = __reserved_mem_alloc_in_range(size, align,
313 start, end, nomap, &base);
314 if (ret == 0) {
315 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
316 uname, &base,
317 (unsigned long)(size / SZ_1M));
318 break;
319 }
320 len -= t_len;
321 }
322
323 } else {
324 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
325 0, 0, nomap, &base);
326 if (ret == 0)
327 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
328 uname, &base, (unsigned long)(size / SZ_1M));
329 }
330
331 if (base == 0) {
332 pr_err("failed to allocate memory for node '%s': size %lu MiB\n",
333 uname, (unsigned long)(size / SZ_1M));
334 return -ENOMEM;
335 }
336
337 *res_base = base;
338 *res_size = size;
339
340 return 0;
341}
342
343static const struct of_device_id __rmem_of_table_sentinel
344 __used __section("__reservedmem_of_table_end");
345
346/*
347 * __reserved_mem_init_node() - call region specific reserved memory init code
348 */
349static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
350{
351 extern const struct of_device_id __reservedmem_of_table[];
352 const struct of_device_id *i;
353 int ret = -ENOENT;
354
355 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
356 reservedmem_of_init_fn initfn = i->data;
357 const char *compat = i->compatible;
358
359 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
360 continue;
361
362 ret = initfn(rmem);
363 if (ret == 0) {
364 pr_info("initialized node %s, compatible id %s\n",
365 rmem->name, compat);
366 break;
367 }
368 }
369 return ret;
370}
371
372static int __init __rmem_cmp(const void *a, const void *b)
373{
374 const struct reserved_mem *ra = a, *rb = b;
375
376 if (ra->base < rb->base)
377 return -1;
378
379 if (ra->base > rb->base)
380 return 1;
381
382 /*
383 * Put the dynamic allocations (address == 0, size == 0) before static
384 * allocations at address 0x0 so that overlap detection works
385 * correctly.
386 */
387 if (ra->size < rb->size)
388 return -1;
389 if (ra->size > rb->size)
390 return 1;
391
392 if (ra->fdt_node < rb->fdt_node)
393 return -1;
394 if (ra->fdt_node > rb->fdt_node)
395 return 1;
396
397 return 0;
398}
399
400static void __init __rmem_check_for_overlap(void)
401{
402 int i;
403
404 if (reserved_mem_count < 2)
405 return;
406
407 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
408 __rmem_cmp, NULL);
409 for (i = 0; i < reserved_mem_count - 1; i++) {
410 struct reserved_mem *this, *next;
411
412 this = &reserved_mem[i];
413 next = &reserved_mem[i + 1];
414
415 if (this->base + this->size > next->base) {
416 phys_addr_t this_end, next_end;
417
418 this_end = this->base + this->size;
419 next_end = next->base + next->size;
420 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
421 this->name, &this->base, &this_end,
422 next->name, &next->base, &next_end);
423 }
424 }
425}
426
427/**
428 * fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
429 */
430void __init fdt_init_reserved_mem(void)
431{
432 int i;
433
434 /* check for overlapping reserved regions */
435 __rmem_check_for_overlap();
436
437 for (i = 0; i < reserved_mem_count; i++) {
438 struct reserved_mem *rmem = &reserved_mem[i];
439 unsigned long node = rmem->fdt_node;
440 int len;
441 const __be32 *prop;
442 int err = 0;
443 bool nomap;
444
445 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
446 prop = of_get_flat_dt_prop(node, "phandle", &len);
447 if (!prop)
448 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
449 if (prop)
450 rmem->phandle = of_read_number(prop, len/4);
451
452 if (rmem->size == 0)
453 err = __reserved_mem_alloc_size(node, rmem->name,
454 &rmem->base, &rmem->size);
455 if (err == 0) {
456 err = __reserved_mem_init_node(rmem);
457 if (err != 0 && err != -ENOENT) {
458 pr_info("node %s compatible matching fail\n",
459 rmem->name);
460 if (nomap)
461 memblock_clear_nomap(rmem->base, rmem->size);
462 else
463 memblock_phys_free(rmem->base,
464 rmem->size);
465 } else {
466 phys_addr_t end = rmem->base + rmem->size - 1;
467 bool reusable =
468 (of_get_flat_dt_prop(node, "reusable", NULL)) != NULL;
469
470 pr_info("%pa..%pa (%lu KiB) %s %s %s\n",
471 &rmem->base, &end, (unsigned long)(rmem->size / SZ_1K),
472 nomap ? "nomap" : "map",
473 reusable ? "reusable" : "non-reusable",
474 rmem->name ? rmem->name : "unknown");
475 }
476 }
477 }
478}
479
480static inline struct reserved_mem *__find_rmem(struct device_node *node)
481{
482 unsigned int i;
483
484 if (!node->phandle)
485 return NULL;
486
487 for (i = 0; i < reserved_mem_count; i++)
488 if (reserved_mem[i].phandle == node->phandle)
489 return &reserved_mem[i];
490 return NULL;
491}
492
493struct rmem_assigned_device {
494 struct device *dev;
495 struct reserved_mem *rmem;
496 struct list_head list;
497};
498
499static LIST_HEAD(of_rmem_assigned_device_list);
500static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
501
502/**
503 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
504 * given device
505 * @dev: Pointer to the device to configure
506 * @np: Pointer to the device_node with 'reserved-memory' property
507 * @idx: Index of selected region
508 *
509 * This function assigns respective DMA-mapping operations based on reserved
510 * memory region specified by 'memory-region' property in @np node to the @dev
511 * device. When driver needs to use more than one reserved memory region, it
512 * should allocate child devices and initialize regions by name for each of
513 * child device.
514 *
515 * Returns error code or zero on success.
516 */
517int of_reserved_mem_device_init_by_idx(struct device *dev,
518 struct device_node *np, int idx)
519{
520 struct rmem_assigned_device *rd;
521 struct device_node *target;
522 struct reserved_mem *rmem;
523 int ret;
524
525 if (!np || !dev)
526 return -EINVAL;
527
528 target = of_parse_phandle(np, "memory-region", idx);
529 if (!target)
530 return -ENODEV;
531
532 if (!of_device_is_available(target)) {
533 of_node_put(target);
534 return 0;
535 }
536
537 rmem = __find_rmem(target);
538 of_node_put(target);
539
540 if (!rmem || !rmem->ops || !rmem->ops->device_init)
541 return -EINVAL;
542
543 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
544 if (!rd)
545 return -ENOMEM;
546
547 ret = rmem->ops->device_init(rmem, dev);
548 if (ret == 0) {
549 rd->dev = dev;
550 rd->rmem = rmem;
551
552 mutex_lock(&of_rmem_assigned_device_mutex);
553 list_add(&rd->list, &of_rmem_assigned_device_list);
554 mutex_unlock(&of_rmem_assigned_device_mutex);
555
556 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
557 } else {
558 kfree(rd);
559 }
560
561 return ret;
562}
563EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
564
565/**
566 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
567 * to given device
568 * @dev: pointer to the device to configure
569 * @np: pointer to the device node with 'memory-region' property
570 * @name: name of the selected memory region
571 *
572 * Returns: 0 on success or a negative error-code on failure.
573 */
574int of_reserved_mem_device_init_by_name(struct device *dev,
575 struct device_node *np,
576 const char *name)
577{
578 int idx = of_property_match_string(np, "memory-region-names", name);
579
580 return of_reserved_mem_device_init_by_idx(dev, np, idx);
581}
582EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
583
584/**
585 * of_reserved_mem_device_release() - release reserved memory device structures
586 * @dev: Pointer to the device to deconfigure
587 *
588 * This function releases structures allocated for memory region handling for
589 * the given device.
590 */
591void of_reserved_mem_device_release(struct device *dev)
592{
593 struct rmem_assigned_device *rd, *tmp;
594 LIST_HEAD(release_list);
595
596 mutex_lock(&of_rmem_assigned_device_mutex);
597 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
598 if (rd->dev == dev)
599 list_move_tail(&rd->list, &release_list);
600 }
601 mutex_unlock(&of_rmem_assigned_device_mutex);
602
603 list_for_each_entry_safe(rd, tmp, &release_list, list) {
604 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
605 rd->rmem->ops->device_release(rd->rmem, dev);
606
607 kfree(rd);
608 }
609}
610EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
611
612/**
613 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
614 * @np: node pointer of the desired reserved-memory region
615 *
616 * This function allows drivers to acquire a reference to the reserved_mem
617 * struct based on a device node handle.
618 *
619 * Returns a reserved_mem reference, or NULL on error.
620 */
621struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
622{
623 const char *name;
624 int i;
625
626 if (!np->full_name)
627 return NULL;
628
629 name = kbasename(np->full_name);
630 for (i = 0; i < reserved_mem_count; i++)
631 if (!strcmp(reserved_mem[i].name, name))
632 return &reserved_mem[i];
633
634 return NULL;
635}
636EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);