1 /* 2 * Device tree based initialization code for reserved memory. 3 * 4 * Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved. 5 * Copyright (c) 2013,2014 Samsung Electronics Co., Ltd. 6 * http://www.samsung.com 7 * Author: Marek Szyprowski <m.szyprowski@samsung.com> 8 * Author: Josh Cartwright <joshc@codeaurora.org> 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License as 12 * published by the Free Software Foundation; either version 2 of the 13 * License or (at your optional) any later version of the license. 14 */ 15 16 #include <linux/err.h> 17 #include <linux/of.h> 18 #include <linux/of_fdt.h> 19 #include <linux/of_platform.h> 20 #include <linux/mm.h> 21 #include <linux/sizes.h> 22 #include <linux/of_reserved_mem.h> 23 #include <linux/sort.h> 24 #include <linux/slab.h> 25 26 #define MAX_RESERVED_REGIONS 16 27 static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS]; 28 static int reserved_mem_count; 29 30 #if defined(CONFIG_HAVE_MEMBLOCK) 31 #include <linux/memblock.h> 32 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, 33 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap, 34 phys_addr_t *res_base) 35 { 36 phys_addr_t base; 37 /* 38 * We use __memblock_alloc_base() because memblock_alloc_base() 39 * panic()s on allocation failure. 40 */ 41 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end; 42 base = __memblock_alloc_base(size, align, end); 43 if (!base) 44 return -ENOMEM; 45 46 /* 47 * Check if the allocated region fits in to start..end window 48 */ 49 if (base < start) { 50 memblock_free(base, size); 51 return -ENOMEM; 52 } 53 54 *res_base = base; 55 if (nomap) 56 return memblock_remove(base, size); 57 return 0; 58 } 59 #else 60 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, 61 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap, 62 phys_addr_t *res_base) 63 { 64 pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n", 65 size, nomap ? " (nomap)" : ""); 66 return -ENOSYS; 67 } 68 #endif 69 70 /** 71 * res_mem_save_node() - save fdt node for second pass initialization 72 */ 73 void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname, 74 phys_addr_t base, phys_addr_t size) 75 { 76 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count]; 77 78 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) { 79 pr_err("Reserved memory: not enough space all defined regions.\n"); 80 return; 81 } 82 83 rmem->fdt_node = node; 84 rmem->name = uname; 85 rmem->base = base; 86 rmem->size = size; 87 88 reserved_mem_count++; 89 return; 90 } 91 92 /** 93 * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align' 94 * and 'alloc-ranges' properties 95 */ 96 static int __init __reserved_mem_alloc_size(unsigned long node, 97 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size) 98 { 99 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32); 100 phys_addr_t start = 0, end = 0; 101 phys_addr_t base = 0, align = 0, size; 102 int len; 103 const __be32 *prop; 104 int nomap; 105 int ret; 106 107 prop = of_get_flat_dt_prop(node, "size", &len); 108 if (!prop) 109 return -EINVAL; 110 111 if (len != dt_root_size_cells * sizeof(__be32)) { 112 pr_err("Reserved memory: invalid size property in '%s' node.\n", 113 uname); 114 return -EINVAL; 115 } 116 size = dt_mem_next_cell(dt_root_size_cells, &prop); 117 118 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; 119 120 prop = of_get_flat_dt_prop(node, "alignment", &len); 121 if (prop) { 122 if (len != dt_root_addr_cells * sizeof(__be32)) { 123 pr_err("Reserved memory: invalid alignment property in '%s' node.\n", 124 uname); 125 return -EINVAL; 126 } 127 align = dt_mem_next_cell(dt_root_addr_cells, &prop); 128 } 129 130 /* Need adjust the alignment to satisfy the CMA requirement */ 131 if (IS_ENABLED(CONFIG_CMA) && of_flat_dt_is_compatible(node, "shared-dma-pool")) 132 align = max(align, (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); 133 134 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len); 135 if (prop) { 136 137 if (len % t_len != 0) { 138 pr_err("Reserved memory: invalid alloc-ranges property in '%s', skipping node.\n", 139 uname); 140 return -EINVAL; 141 } 142 143 base = 0; 144 145 while (len > 0) { 146 start = dt_mem_next_cell(dt_root_addr_cells, &prop); 147 end = start + dt_mem_next_cell(dt_root_size_cells, 148 &prop); 149 150 ret = early_init_dt_alloc_reserved_memory_arch(size, 151 align, start, end, nomap, &base); 152 if (ret == 0) { 153 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n", 154 uname, &base, 155 (unsigned long)size / SZ_1M); 156 break; 157 } 158 len -= t_len; 159 } 160 161 } else { 162 ret = early_init_dt_alloc_reserved_memory_arch(size, align, 163 0, 0, nomap, &base); 164 if (ret == 0) 165 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n", 166 uname, &base, (unsigned long)size / SZ_1M); 167 } 168 169 if (base == 0) { 170 pr_info("Reserved memory: failed to allocate memory for node '%s'\n", 171 uname); 172 return -ENOMEM; 173 } 174 175 *res_base = base; 176 *res_size = size; 177 178 return 0; 179 } 180 181 static const struct of_device_id __rmem_of_table_sentinel 182 __used __section(__reservedmem_of_table_end); 183 184 /** 185 * res_mem_init_node() - call region specific reserved memory init code 186 */ 187 static int __init __reserved_mem_init_node(struct reserved_mem *rmem) 188 { 189 extern const struct of_device_id __reservedmem_of_table[]; 190 const struct of_device_id *i; 191 192 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) { 193 reservedmem_of_init_fn initfn = i->data; 194 const char *compat = i->compatible; 195 196 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat)) 197 continue; 198 199 if (initfn(rmem) == 0) { 200 pr_info("Reserved memory: initialized node %s, compatible id %s\n", 201 rmem->name, compat); 202 return 0; 203 } 204 } 205 return -ENOENT; 206 } 207 208 static int __init __rmem_cmp(const void *a, const void *b) 209 { 210 const struct reserved_mem *ra = a, *rb = b; 211 212 if (ra->base < rb->base) 213 return -1; 214 215 if (ra->base > rb->base) 216 return 1; 217 218 return 0; 219 } 220 221 static void __init __rmem_check_for_overlap(void) 222 { 223 int i; 224 225 if (reserved_mem_count < 2) 226 return; 227 228 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]), 229 __rmem_cmp, NULL); 230 for (i = 0; i < reserved_mem_count - 1; i++) { 231 struct reserved_mem *this, *next; 232 233 this = &reserved_mem[i]; 234 next = &reserved_mem[i + 1]; 235 if (!(this->base && next->base)) 236 continue; 237 if (this->base + this->size > next->base) { 238 phys_addr_t this_end, next_end; 239 240 this_end = this->base + this->size; 241 next_end = next->base + next->size; 242 pr_err("Reserved memory: OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n", 243 this->name, &this->base, &this_end, 244 next->name, &next->base, &next_end); 245 } 246 } 247 } 248 249 /** 250 * fdt_init_reserved_mem - allocate and init all saved reserved memory regions 251 */ 252 void __init fdt_init_reserved_mem(void) 253 { 254 int i; 255 256 /* check for overlapping reserved regions */ 257 __rmem_check_for_overlap(); 258 259 for (i = 0; i < reserved_mem_count; i++) { 260 struct reserved_mem *rmem = &reserved_mem[i]; 261 unsigned long node = rmem->fdt_node; 262 int len; 263 const __be32 *prop; 264 int err = 0; 265 266 prop = of_get_flat_dt_prop(node, "phandle", &len); 267 if (!prop) 268 prop = of_get_flat_dt_prop(node, "linux,phandle", &len); 269 if (prop) 270 rmem->phandle = of_read_number(prop, len/4); 271 272 if (rmem->size == 0) 273 err = __reserved_mem_alloc_size(node, rmem->name, 274 &rmem->base, &rmem->size); 275 if (err == 0) 276 __reserved_mem_init_node(rmem); 277 } 278 } 279 280 static inline struct reserved_mem *__find_rmem(struct device_node *node) 281 { 282 unsigned int i; 283 284 if (!node->phandle) 285 return NULL; 286 287 for (i = 0; i < reserved_mem_count; i++) 288 if (reserved_mem[i].phandle == node->phandle) 289 return &reserved_mem[i]; 290 return NULL; 291 } 292 293 struct rmem_assigned_device { 294 struct device *dev; 295 struct reserved_mem *rmem; 296 struct list_head list; 297 }; 298 299 static LIST_HEAD(of_rmem_assigned_device_list); 300 static DEFINE_MUTEX(of_rmem_assigned_device_mutex); 301 302 /** 303 * of_reserved_mem_device_init_by_idx() - assign reserved memory region to 304 * given device 305 * @dev: Pointer to the device to configure 306 * @np: Pointer to the device_node with 'reserved-memory' property 307 * @idx: Index of selected region 308 * 309 * This function assigns respective DMA-mapping operations based on reserved 310 * memory region specified by 'memory-region' property in @np node to the @dev 311 * device. When driver needs to use more than one reserved memory region, it 312 * should allocate child devices and initialize regions by name for each of 313 * child device. 314 * 315 * Returns error code or zero on success. 316 */ 317 int of_reserved_mem_device_init_by_idx(struct device *dev, 318 struct device_node *np, int idx) 319 { 320 struct rmem_assigned_device *rd; 321 struct device_node *target; 322 struct reserved_mem *rmem; 323 int ret; 324 325 if (!np || !dev) 326 return -EINVAL; 327 328 target = of_parse_phandle(np, "memory-region", idx); 329 if (!target) 330 return -ENODEV; 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 } 358 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx); 359 360 /** 361 * of_reserved_mem_device_release() - release reserved memory device structures 362 * @dev: Pointer to the device to deconfigure 363 * 364 * This function releases structures allocated for memory region handling for 365 * the given device. 366 */ 367 void of_reserved_mem_device_release(struct device *dev) 368 { 369 struct rmem_assigned_device *rd; 370 struct reserved_mem *rmem = NULL; 371 372 mutex_lock(&of_rmem_assigned_device_mutex); 373 list_for_each_entry(rd, &of_rmem_assigned_device_list, list) { 374 if (rd->dev == dev) { 375 rmem = rd->rmem; 376 list_del(&rd->list); 377 kfree(rd); 378 break; 379 } 380 } 381 mutex_unlock(&of_rmem_assigned_device_mutex); 382 383 if (!rmem || !rmem->ops || !rmem->ops->device_release) 384 return; 385 386 rmem->ops->device_release(rmem, dev); 387 } 388 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release); 389