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 25 #define MAX_RESERVED_REGIONS 16 26 static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS]; 27 static int reserved_mem_count; 28 29 #if defined(CONFIG_HAVE_MEMBLOCK) 30 #include <linux/memblock.h> 31 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, 32 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap, 33 phys_addr_t *res_base) 34 { 35 phys_addr_t base; 36 /* 37 * We use __memblock_alloc_base() because memblock_alloc_base() 38 * panic()s on allocation failure. 39 */ 40 end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end; 41 base = __memblock_alloc_base(size, align, end); 42 if (!base) 43 return -ENOMEM; 44 45 /* 46 * Check if the allocated region fits in to start..end window 47 */ 48 if (base < start) { 49 memblock_free(base, size); 50 return -ENOMEM; 51 } 52 53 *res_base = base; 54 if (nomap) 55 return memblock_remove(base, size); 56 return 0; 57 } 58 #else 59 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, 60 phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap, 61 phys_addr_t *res_base) 62 { 63 pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n", 64 size, nomap ? " (nomap)" : ""); 65 return -ENOSYS; 66 } 67 #endif 68 69 /** 70 * res_mem_save_node() - save fdt node for second pass initialization 71 */ 72 void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname, 73 phys_addr_t base, phys_addr_t size) 74 { 75 struct reserved_mem *rmem = &reserved_mem[reserved_mem_count]; 76 77 if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) { 78 pr_err("Reserved memory: not enough space all defined regions.\n"); 79 return; 80 } 81 82 rmem->fdt_node = node; 83 rmem->name = uname; 84 rmem->base = base; 85 rmem->size = size; 86 87 reserved_mem_count++; 88 return; 89 } 90 91 /** 92 * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align' 93 * and 'alloc-ranges' properties 94 */ 95 static int __init __reserved_mem_alloc_size(unsigned long node, 96 const char *uname, phys_addr_t *res_base, phys_addr_t *res_size) 97 { 98 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32); 99 phys_addr_t start = 0, end = 0; 100 phys_addr_t base = 0, align = 0, size; 101 int len; 102 const __be32 *prop; 103 int nomap; 104 int ret; 105 106 prop = of_get_flat_dt_prop(node, "size", &len); 107 if (!prop) 108 return -EINVAL; 109 110 if (len != dt_root_size_cells * sizeof(__be32)) { 111 pr_err("Reserved memory: invalid size property in '%s' node.\n", 112 uname); 113 return -EINVAL; 114 } 115 size = dt_mem_next_cell(dt_root_size_cells, &prop); 116 117 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; 118 119 prop = of_get_flat_dt_prop(node, "alignment", &len); 120 if (prop) { 121 if (len != dt_root_addr_cells * sizeof(__be32)) { 122 pr_err("Reserved memory: invalid alignment property in '%s' node.\n", 123 uname); 124 return -EINVAL; 125 } 126 align = dt_mem_next_cell(dt_root_addr_cells, &prop); 127 } 128 129 /* Need adjust the alignment to satisfy the CMA requirement */ 130 if (IS_ENABLED(CONFIG_CMA) && of_flat_dt_is_compatible(node, "shared-dma-pool")) 131 align = max(align, (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); 132 133 prop = of_get_flat_dt_prop(node, "alloc-ranges", &len); 134 if (prop) { 135 136 if (len % t_len != 0) { 137 pr_err("Reserved memory: invalid alloc-ranges property in '%s', skipping node.\n", 138 uname); 139 return -EINVAL; 140 } 141 142 base = 0; 143 144 while (len > 0) { 145 start = dt_mem_next_cell(dt_root_addr_cells, &prop); 146 end = start + dt_mem_next_cell(dt_root_size_cells, 147 &prop); 148 149 ret = early_init_dt_alloc_reserved_memory_arch(size, 150 align, start, end, nomap, &base); 151 if (ret == 0) { 152 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n", 153 uname, &base, 154 (unsigned long)size / SZ_1M); 155 break; 156 } 157 len -= t_len; 158 } 159 160 } else { 161 ret = early_init_dt_alloc_reserved_memory_arch(size, align, 162 0, 0, nomap, &base); 163 if (ret == 0) 164 pr_debug("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n", 165 uname, &base, (unsigned long)size / SZ_1M); 166 } 167 168 if (base == 0) { 169 pr_info("Reserved memory: failed to allocate memory for node '%s'\n", 170 uname); 171 return -ENOMEM; 172 } 173 174 *res_base = base; 175 *res_size = size; 176 177 return 0; 178 } 179 180 static const struct of_device_id __rmem_of_table_sentinel 181 __used __section(__reservedmem_of_table_end); 182 183 /** 184 * res_mem_init_node() - call region specific reserved memory init code 185 */ 186 static int __init __reserved_mem_init_node(struct reserved_mem *rmem) 187 { 188 extern const struct of_device_id __reservedmem_of_table[]; 189 const struct of_device_id *i; 190 191 for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) { 192 reservedmem_of_init_fn initfn = i->data; 193 const char *compat = i->compatible; 194 195 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat)) 196 continue; 197 198 if (initfn(rmem) == 0) { 199 pr_info("Reserved memory: initialized node %s, compatible id %s\n", 200 rmem->name, compat); 201 return 0; 202 } 203 } 204 return -ENOENT; 205 } 206 207 static int __init __rmem_cmp(const void *a, const void *b) 208 { 209 const struct reserved_mem *ra = a, *rb = b; 210 211 if (ra->base < rb->base) 212 return -1; 213 214 if (ra->base > rb->base) 215 return 1; 216 217 return 0; 218 } 219 220 static void __init __rmem_check_for_overlap(void) 221 { 222 int i; 223 224 if (reserved_mem_count < 2) 225 return; 226 227 sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]), 228 __rmem_cmp, NULL); 229 for (i = 0; i < reserved_mem_count - 1; i++) { 230 struct reserved_mem *this, *next; 231 232 this = &reserved_mem[i]; 233 next = &reserved_mem[i + 1]; 234 if (!(this->base && next->base)) 235 continue; 236 if (this->base + this->size > next->base) { 237 phys_addr_t this_end, next_end; 238 239 this_end = this->base + this->size; 240 next_end = next->base + next->size; 241 pr_err("Reserved memory: OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n", 242 this->name, &this->base, &this_end, 243 next->name, &next->base, &next_end); 244 } 245 } 246 } 247 248 /** 249 * fdt_init_reserved_mem - allocate and init all saved reserved memory regions 250 */ 251 void __init fdt_init_reserved_mem(void) 252 { 253 int i; 254 255 /* check for overlapping reserved regions */ 256 __rmem_check_for_overlap(); 257 258 for (i = 0; i < reserved_mem_count; i++) { 259 struct reserved_mem *rmem = &reserved_mem[i]; 260 unsigned long node = rmem->fdt_node; 261 int len; 262 const __be32 *prop; 263 int err = 0; 264 265 prop = of_get_flat_dt_prop(node, "phandle", &len); 266 if (!prop) 267 prop = of_get_flat_dt_prop(node, "linux,phandle", &len); 268 if (prop) 269 rmem->phandle = of_read_number(prop, len/4); 270 271 if (rmem->size == 0) 272 err = __reserved_mem_alloc_size(node, rmem->name, 273 &rmem->base, &rmem->size); 274 if (err == 0) 275 __reserved_mem_init_node(rmem); 276 } 277 } 278 279 static inline struct reserved_mem *__find_rmem(struct device_node *node) 280 { 281 unsigned int i; 282 283 if (!node->phandle) 284 return NULL; 285 286 for (i = 0; i < reserved_mem_count; i++) 287 if (reserved_mem[i].phandle == node->phandle) 288 return &reserved_mem[i]; 289 return NULL; 290 } 291 292 /** 293 * of_reserved_mem_device_init() - assign reserved memory region to given device 294 * 295 * This function assign memory region pointed by "memory-region" device tree 296 * property to the given device. 297 */ 298 int of_reserved_mem_device_init(struct device *dev) 299 { 300 struct reserved_mem *rmem; 301 struct device_node *np; 302 int ret; 303 304 np = of_parse_phandle(dev->of_node, "memory-region", 0); 305 if (!np) 306 return -ENODEV; 307 308 rmem = __find_rmem(np); 309 of_node_put(np); 310 311 if (!rmem || !rmem->ops || !rmem->ops->device_init) 312 return -EINVAL; 313 314 ret = rmem->ops->device_init(rmem, dev); 315 if (ret == 0) 316 dev_info(dev, "assigned reserved memory node %s\n", rmem->name); 317 318 return ret; 319 } 320 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init); 321 322 /** 323 * of_reserved_mem_device_release() - release reserved memory device structures 324 * 325 * This function releases structures allocated for memory region handling for 326 * the given device. 327 */ 328 void of_reserved_mem_device_release(struct device *dev) 329 { 330 struct reserved_mem *rmem; 331 struct device_node *np; 332 333 np = of_parse_phandle(dev->of_node, "memory-region", 0); 334 if (!np) 335 return; 336 337 rmem = __find_rmem(np); 338 of_node_put(np); 339 340 if (!rmem || !rmem->ops || !rmem->ops->device_release) 341 return; 342 343 rmem->ops->device_release(rmem, dev); 344 } 345 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release); 346