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 #if defined(CONFIG_DEBUG_FS)
26 #include <linux/debugfs.h>
27 #include <linux/seq_file.h>
28 #endif
29
30 #define MAX_RESERVED_REGIONS 64
31 static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
32 static int reserved_mem_count;
33 #if defined(CONFIG_DEBUG_FS)
34 #define DT_RESERVED_MEM "dt_reserved_mem"
35 static int dynamic_reserved_mem_count;
36 static const char *dynamic_reserved_mem_array[MAX_RESERVED_REGIONS];
37 static int cma_reserved_mem_count;
38 static const char *cma_reserved_mem_array[MAX_RESERVED_REGIONS];
39 #endif
40
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)41 static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
42 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
43 phys_addr_t *res_base)
44 {
45 phys_addr_t base;
46
47 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
48 align = !align ? SMP_CACHE_BYTES : align;
49 base = memblock_find_in_range(start, end, size, align);
50 if (!base)
51 return -ENOMEM;
52
53 *res_base = base;
54 if (nomap)
55 return memblock_remove(base, size);
56
57 return memblock_reserve(base, size);
58 }
59
60 /**
61 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization
62 */
fdt_reserved_mem_save_node(unsigned long node,const char * uname,phys_addr_t base,phys_addr_t size)63 void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
64 phys_addr_t base, phys_addr_t size)
65 {
66 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
67
68 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
69 pr_err("not enough space for all defined regions.\n");
70 return;
71 }
72
73 rmem->fdt_node = node;
74 rmem->name = uname;
75 rmem->base = base;
76 rmem->size = size;
77 #if defined(CONFIG_DEBUG_FS)
78 if ((of_get_flat_dt_prop(node, "reusable", NULL))
79 && (cma_reserved_mem_count < MAX_RESERVED_REGIONS)) {
80 cma_reserved_mem_array[cma_reserved_mem_count] = uname;
81 cma_reserved_mem_count++;
82 }
83 #endif
84
85 reserved_mem_count++;
86 return;
87 }
88
89 /**
90 * __reserved_mem_alloc_size() - allocate reserved memory described by
91 * 'size', 'alignment' and 'alloc-ranges' properties.
92 */
__reserved_mem_alloc_size(unsigned long node,const char * uname,phys_addr_t * res_base,phys_addr_t * res_size)93 static int __init __reserved_mem_alloc_size(unsigned long node,
94 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
95 {
96 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
97 phys_addr_t start = 0, end = 0;
98 phys_addr_t base = 0, align = 0, size;
99 int len;
100 const __be32 *prop;
101 bool nomap;
102 int ret;
103
104 prop = of_get_flat_dt_prop(node, "size", &len);
105 if (!prop)
106 return -EINVAL;
107
108 if (len != dt_root_size_cells * sizeof(__be32)) {
109 pr_err("invalid size property in '%s' node.\n", uname);
110 return -EINVAL;
111 }
112 size = dt_mem_next_cell(dt_root_size_cells, &prop);
113
114 prop = of_get_flat_dt_prop(node, "alignment", &len);
115 if (prop) {
116 if (len != dt_root_addr_cells * sizeof(__be32)) {
117 pr_err("invalid alignment property in '%s' node.\n",
118 uname);
119 return -EINVAL;
120 }
121 align = dt_mem_next_cell(dt_root_addr_cells, &prop);
122 }
123
124 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
125
126 /* Need adjust the alignment to satisfy the CMA requirement */
127 if (IS_ENABLED(CONFIG_CMA)
128 && of_flat_dt_is_compatible(node, "shared-dma-pool")
129 && of_get_flat_dt_prop(node, "reusable", NULL)
130 && !nomap) {
131 unsigned long order =
132 max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
133
134 align = max(align, (phys_addr_t)PAGE_SIZE << order);
135 }
136
137 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
138 if (prop) {
139
140 if (len % t_len != 0) {
141 pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
142 uname);
143 return -EINVAL;
144 }
145
146 base = 0;
147
148 while (len > 0) {
149 start = dt_mem_next_cell(dt_root_addr_cells, &prop);
150 end = start + dt_mem_next_cell(dt_root_size_cells,
151 &prop);
152
153 ret = early_init_dt_alloc_reserved_memory_arch(size,
154 align, start, end, nomap, &base);
155 if (ret == 0) {
156 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
157 uname, &base,
158 (unsigned long)(size / SZ_1M));
159 break;
160 }
161 len -= t_len;
162 }
163
164 } else {
165 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
166 0, 0, nomap, &base);
167 if (ret == 0)
168 pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
169 uname, &base, (unsigned long)(size / SZ_1M));
170 }
171
172 if (base == 0) {
173 pr_info("failed to allocate memory for node '%s'\n", uname);
174 return -ENOMEM;
175 }
176
177 #if defined(CONFIG_DEBUG_FS)
178 if (dynamic_reserved_mem_count < MAX_RESERVED_REGIONS) {
179 dynamic_reserved_mem_array[dynamic_reserved_mem_count] = uname;
180 dynamic_reserved_mem_count++;
181 }
182 #endif
183
184 *res_base = base;
185 *res_size = size;
186
187 return 0;
188 }
189
190 static const struct of_device_id __rmem_of_table_sentinel
191 __used __section("__reservedmem_of_table_end");
192
193 /**
194 * __reserved_mem_init_node() - call region specific reserved memory init code
195 */
__reserved_mem_init_node(struct reserved_mem * rmem)196 static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
197 {
198 extern const struct of_device_id __reservedmem_of_table[];
199 const struct of_device_id *i;
200 int ret = -ENOENT;
201
202 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
203 reservedmem_of_init_fn initfn = i->data;
204 const char *compat = i->compatible;
205
206 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
207 continue;
208
209 ret = initfn(rmem);
210 if (ret == 0) {
211 pr_info("initialized node %s, compatible id %s\n",
212 rmem->name, compat);
213 break;
214 }
215 }
216 return ret;
217 }
218
__rmem_cmp(const void * a,const void * b)219 static int __init __rmem_cmp(const void *a, const void *b)
220 {
221 const struct reserved_mem *ra = a, *rb = b;
222
223 if (ra->base < rb->base)
224 return -1;
225
226 if (ra->base > rb->base)
227 return 1;
228
229 /*
230 * Put the dynamic allocations (address == 0, size == 0) before static
231 * allocations at address 0x0 so that overlap detection works
232 * correctly.
233 */
234 if (ra->size < rb->size)
235 return -1;
236 if (ra->size > rb->size)
237 return 1;
238
239 return 0;
240 }
241
__rmem_check_for_overlap(void)242 static void __init __rmem_check_for_overlap(void)
243 {
244 int i;
245
246 if (reserved_mem_count < 2)
247 return;
248
249 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
250 __rmem_cmp, NULL);
251 for (i = 0; i < reserved_mem_count - 1; i++) {
252 struct reserved_mem *this, *next;
253
254 this = &reserved_mem[i];
255 next = &reserved_mem[i + 1];
256
257 if (this->base + this->size > next->base) {
258 phys_addr_t this_end, next_end;
259
260 this_end = this->base + this->size;
261 next_end = next->base + next->size;
262 pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
263 this->name, &this->base, &this_end,
264 next->name, &next->base, &next_end);
265 }
266 }
267 }
268
269 /**
270 * fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
271 */
fdt_init_reserved_mem(void)272 void __init fdt_init_reserved_mem(void)
273 {
274 int i;
275
276 /* check for overlapping reserved regions */
277 __rmem_check_for_overlap();
278
279 for (i = 0; i < reserved_mem_count; i++) {
280 struct reserved_mem *rmem = &reserved_mem[i];
281 unsigned long node = rmem->fdt_node;
282 int len;
283 const __be32 *prop;
284 int err = 0;
285 bool nomap;
286
287 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
288 prop = of_get_flat_dt_prop(node, "phandle", &len);
289 if (!prop)
290 prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
291 if (prop)
292 rmem->phandle = of_read_number(prop, len/4);
293
294 if (rmem->size == 0)
295 err = __reserved_mem_alloc_size(node, rmem->name,
296 &rmem->base, &rmem->size);
297 if (err == 0) {
298 err = __reserved_mem_init_node(rmem);
299 if (err != 0 && err != -ENOENT) {
300 pr_info("node %s compatible matching fail\n",
301 rmem->name);
302 memblock_free(rmem->base, rmem->size);
303 if (nomap)
304 memblock_add(rmem->base, rmem->size);
305 }
306 }
307 }
308 }
309
__find_rmem(struct device_node * node)310 static inline struct reserved_mem *__find_rmem(struct device_node *node)
311 {
312 unsigned int i;
313
314 if (!node->phandle)
315 return NULL;
316
317 for (i = 0; i < reserved_mem_count; i++)
318 if (reserved_mem[i].phandle == node->phandle)
319 return &reserved_mem[i];
320 return NULL;
321 }
322
323 struct rmem_assigned_device {
324 struct device *dev;
325 struct reserved_mem *rmem;
326 struct list_head list;
327 };
328
329 static LIST_HEAD(of_rmem_assigned_device_list);
330 static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
331
332 /**
333 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
334 * given device
335 * @dev: Pointer to the device to configure
336 * @np: Pointer to the device_node with 'reserved-memory' property
337 * @idx: Index of selected region
338 *
339 * This function assigns respective DMA-mapping operations based on reserved
340 * memory region specified by 'memory-region' property in @np node to the @dev
341 * device. When driver needs to use more than one reserved memory region, it
342 * should allocate child devices and initialize regions by name for each of
343 * child device.
344 *
345 * Returns error code or zero on success.
346 */
of_reserved_mem_device_init_by_idx(struct device * dev,struct device_node * np,int idx)347 int of_reserved_mem_device_init_by_idx(struct device *dev,
348 struct device_node *np, int idx)
349 {
350 struct rmem_assigned_device *rd;
351 struct device_node *target;
352 struct reserved_mem *rmem;
353 int ret;
354
355 if (!np || !dev)
356 return -EINVAL;
357
358 target = of_parse_phandle(np, "memory-region", idx);
359 if (!target)
360 return -ENODEV;
361
362 if (!of_device_is_available(target)) {
363 of_node_put(target);
364 return 0;
365 }
366
367 rmem = __find_rmem(target);
368 of_node_put(target);
369
370 if (!rmem || !rmem->ops || !rmem->ops->device_init)
371 return -EINVAL;
372
373 rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
374 if (!rd)
375 return -ENOMEM;
376
377 ret = rmem->ops->device_init(rmem, dev);
378 if (ret == 0) {
379 rd->dev = dev;
380 rd->rmem = rmem;
381
382 mutex_lock(&of_rmem_assigned_device_mutex);
383 list_add(&rd->list, &of_rmem_assigned_device_list);
384 mutex_unlock(&of_rmem_assigned_device_mutex);
385
386 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
387 } else {
388 kfree(rd);
389 }
390
391 return ret;
392 }
393 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
394
395 /**
396 * of_reserved_mem_device_init_by_name() - assign named reserved memory region
397 * to given device
398 * @dev: pointer to the device to configure
399 * @np: pointer to the device node with 'memory-region' property
400 * @name: name of the selected memory region
401 *
402 * Returns: 0 on success or a negative error-code on failure.
403 */
of_reserved_mem_device_init_by_name(struct device * dev,struct device_node * np,const char * name)404 int of_reserved_mem_device_init_by_name(struct device *dev,
405 struct device_node *np,
406 const char *name)
407 {
408 int idx = of_property_match_string(np, "memory-region-names", name);
409
410 return of_reserved_mem_device_init_by_idx(dev, np, idx);
411 }
412 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
413
414 /**
415 * of_reserved_mem_device_release() - release reserved memory device structures
416 * @dev: Pointer to the device to deconfigure
417 *
418 * This function releases structures allocated for memory region handling for
419 * the given device.
420 */
of_reserved_mem_device_release(struct device * dev)421 void of_reserved_mem_device_release(struct device *dev)
422 {
423 struct rmem_assigned_device *rd, *tmp;
424 LIST_HEAD(release_list);
425
426 mutex_lock(&of_rmem_assigned_device_mutex);
427 list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
428 if (rd->dev == dev)
429 list_move_tail(&rd->list, &release_list);
430 }
431 mutex_unlock(&of_rmem_assigned_device_mutex);
432
433 list_for_each_entry_safe(rd, tmp, &release_list, list) {
434 if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
435 rd->rmem->ops->device_release(rd->rmem, dev);
436
437 kfree(rd);
438 }
439 }
440 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
441
442 /**
443 * of_reserved_mem_lookup() - acquire reserved_mem from a device node
444 * @np: node pointer of the desired reserved-memory region
445 *
446 * This function allows drivers to acquire a reference to the reserved_mem
447 * struct based on a device node handle.
448 *
449 * Returns a reserved_mem reference, or NULL on error.
450 */
of_reserved_mem_lookup(struct device_node * np)451 struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
452 {
453 const char *name;
454 int i;
455
456 if (!np->full_name)
457 return NULL;
458
459 name = kbasename(np->full_name);
460 for (i = 0; i < reserved_mem_count; i++)
461 if (!strcmp(reserved_mem[i].name, name))
462 return &reserved_mem[i];
463
464 return NULL;
465 }
466 EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);
467
468 #if defined(CONFIG_DEBUG_FS)
dt_reserved_memory_debug_show(struct seq_file * m,void * private)469 static int dt_reserved_memory_debug_show(struct seq_file *m, void *private)
470 {
471 struct reserved_mem *dt_reserved_mem = m->private;
472 struct reserved_mem *rmem = NULL;
473 int i = 0;
474 int j = 0;
475 int cma = 0;
476 int dynamic = 0;
477
478 seq_printf(m, " num [start .... end] [size]"
479 " [d/s] [cma] [name]\n");
480
481 for (i = 0; i < reserved_mem_count; i++) {
482 cma = 0;
483 dynamic = 0;
484 rmem = &(dt_reserved_mem[i]);
485
486 /* find out dynamic reserved memory node */
487 for (j = 0; j < dynamic_reserved_mem_count; j++) {
488 if (!strcmp(rmem->name, dynamic_reserved_mem_array[j])) {
489 dynamic = 1;
490 break;
491 }
492 }
493
494 /* find out cma reserved memory node */
495 for (j = 0; j < cma_reserved_mem_count; j++) {
496 if (!strcmp(rmem->name, cma_reserved_mem_array[j])) {
497 cma = 1;
498 break;
499 }
500 }
501
502 seq_printf(m, "%4d: [0x%016llx..0x%016llx] %8llukB %8s %8s %8s\n",
503 i,
504 (unsigned long long)rmem->base,
505 (unsigned long long)(rmem->base + rmem->size - 1),
506 (unsigned long long)rmem->size / SZ_1K,
507 (dynamic == 1) ? "d" : "s",
508 (cma == 1) ? "y" : "n",
509 rmem->name);
510 }
511
512 return 0;
513 }
514
dt_reserved_memory_debug_open(struct inode * inode,struct file * file)515 static int dt_reserved_memory_debug_open(struct inode *inode, struct file *file)
516 {
517 return single_open(file, dt_reserved_memory_debug_show, inode->i_private);
518 }
519
520 static const struct file_operations dt_reserved_memory_debug_fops = {
521 .open = dt_reserved_memory_debug_open,
522 .read = seq_read,
523 .llseek = seq_lseek,
524 .release = single_release,
525 };
526
dt_reserved_memory_init_debugfs(void)527 static int __init dt_reserved_memory_init_debugfs(void)
528 {
529 struct dentry *root = debugfs_create_dir(DT_RESERVED_MEM, NULL);
530 if (!root)
531 return -ENXIO;
532 debugfs_create_file("dt_reserved_memory",
533 S_IRUGO,
534 root,
535 reserved_mem,
536 &dt_reserved_memory_debug_fops);
537
538 return 0;
539 }
540 __initcall(dt_reserved_memory_init_debugfs);
541 #endif /* CONFIG_DEBUG_FS */
542