drivers/of/of_reserved_mem.c

   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 <[email protected]>
   8  * Author: Josh Cartwright <[email protected]>
   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 #define pr_fmt(fmt)     "OF: reserved mem: " fmt
  17
  18 #include <linux/err.h>
  19 #include <linux/of.h>
  20 #include <linux/of_fdt.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/mm.h>
  23 #include <linux/sizes.h>
  24 #include <linux/of_reserved_mem.h>
  25 #include <linux/sort.h>
  26
  27 #define MAX_RESERVED_REGIONS    16
  28 static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
  29 static int reserved_mem_count;
  30
  31 #if defined(CONFIG_HAVE_MEMBLOCK)
  32 #include <linux/memblock.h>
  33 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
  34         phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
  35         phys_addr_t *res_base)
  36 {
  37         phys_addr_t base;
  38         /*
  39          * We use __memblock_alloc_base() because memblock_alloc_base()
  40          * panic()s on allocation failure.
  41          */
  42         end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
  43         base = __memblock_alloc_base(size, align, end);
  44         if (!base)
  45                 return -ENOMEM;
  46
  47         /*
  48          * Check if the allocated region fits in to start..end window
  49          */
  50         if (base < start) {
  51                 memblock_free(base, size);
  52                 return -ENOMEM;
  53         }
  54
  55         *res_base = base;
  56         if (nomap)
  57                 return memblock_remove(base, size);
  58         return 0;
  59 }
  60 #else
  61 int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
  62         phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
  63         phys_addr_t *res_base)
  64 {
  65         pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
  66                   size, nomap ? " (nomap)" : "");
  67         return -ENOSYS;
  68 }
  69 #endif
  70
  71 /**
  72  * res_mem_save_node() - save fdt node for second pass initialization
  73  */
  74 void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
  75                                       phys_addr_t base, phys_addr_t size)
  76 {
  77         struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
  78
  79         if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
  80                 pr_err("not enough space all defined regions.\n");
  81                 return;
  82         }
  83
  84         rmem->fdt_node = node;
  85         rmem->name = uname;
  86         rmem->base = base;
  87         rmem->size = size;
  88
  89         reserved_mem_count++;
  90         return;
  91 }
  92
  93 /**
  94  * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align'
  95  *                        and 'alloc-ranges' properties
  96  */
  97 static int __init __reserved_mem_alloc_size(unsigned long node,
  98         const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
  99 {
 100         int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
 101         phys_addr_t start = 0, end = 0;
 102         phys_addr_t base = 0, align = 0, size;
 103         int len;
 104         const __be32 *prop;
 105         int nomap;
 106         int ret;
 107
 108         prop = of_get_flat_dt_prop(node, "size", &len);
 109         if (!prop)
 110                 return -EINVAL;
 111
 112         if (len != dt_root_size_cells * sizeof(__be32)) {
 113                 pr_err("invalid size property in '%s' node.\n", 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("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)
 132             && of_flat_dt_is_compatible(node, "shared-dma-pool")
 133             && of_get_flat_dt_prop(node, "reusable", NULL)
 134             && !of_get_flat_dt_prop(node, "no-map", NULL)) {
 135                 unsigned long order =
 136                         max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
 137
 138                 align = max(align, (phys_addr_t)PAGE_SIZE << order);
 139         }
 140
 141         prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
 142         if (prop) {
 143
 144                 if (len % t_len != 0) {
 145                         pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
 146                                uname);
 147                         return -EINVAL;
 148                 }
 149
 150                 base = 0;
 151
 152                 while (len > 0) {
 153                         start = dt_mem_next_cell(dt_root_addr_cells, &prop);
 154                         end = start + dt_mem_next_cell(dt_root_size_cells,
 155                                                        &prop);
 156
 157                         ret = early_init_dt_alloc_reserved_memory_arch(size,
 158                                         align, start, end, nomap, &base);
 159                         if (ret == 0) {
 160                                 pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
 161                                         uname, &base,
 162                                         (unsigned long)size / SZ_1M);
 163                                 break;
 164                         }
 165                         len -= t_len;
 166                 }
 167
 168         } else {
 169                 ret = early_init_dt_alloc_reserved_memory_arch(size, align,
 170                                                         0, 0, nomap, &base);
 171                 if (ret == 0)
 172                         pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
 173                                 uname, &base, (unsigned long)size / SZ_1M);
 174         }
 175
 176         if (base == 0) {
 177                 pr_info("failed to allocate memory for node '%s'\n", uname);
 178                 return -ENOMEM;
 179         }
 180
 181         *res_base = base;
 182         *res_size = size;
 183
 184         return 0;
 185 }
 186
 187 static const struct of_device_id __rmem_of_table_sentinel
 188         __used __section(__reservedmem_of_table_end);
 189
 190 /**
 191  * res_mem_init_node() - call region specific reserved memory init code
 192  */
 193 static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
 194 {
 195         extern const struct of_device_id __reservedmem_of_table[];
 196         const struct of_device_id *i;
 197
 198         for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
 199                 reservedmem_of_init_fn initfn = i->data;
 200                 const char *compat = i->compatible;
 201
 202                 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
 203                         continue;
 204
 205                 if (initfn(rmem) == 0) {
 206                         pr_info("initialized node %s, compatible id %s\n",
 207                                 rmem->name, compat);
 208                         return 0;
 209                 }
 210         }
 211         return -ENOENT;
 212 }
 213
 214 static int __init __rmem_cmp(const void *a, const void *b)
 215 {
 216         const struct reserved_mem *ra = a, *rb = b;
 217
 218         if (ra->base < rb->base)
 219                 return -1;
 220
 221         if (ra->base > rb->base)
 222                 return 1;
 223
 224         return 0;
 225 }
 226
 227 static void __init __rmem_check_for_overlap(void)
 228 {
 229         int i;
 230
 231         if (reserved_mem_count < 2)
 232                 return;
 233
 234         sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
 235              __rmem_cmp, NULL);
 236         for (i = 0; i < reserved_mem_count - 1; i++) {
 237                 struct reserved_mem *this, *next;
 238
 239                 this = &reserved_mem[i];
 240                 next = &reserved_mem[i + 1];
 241                 if (!(this->base && next->base))
 242                         continue;
 243                 if (this->base + this->size > next->base) {
 244                         phys_addr_t this_end, next_end;
 245
 246                         this_end = this->base + this->size;
 247                         next_end = next->base + next->size;
 248                         pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
 249                                this->name, &this->base, &this_end,
 250                                next->name, &next->base, &next_end);
 251                 }
 252         }
 253 }
 254
 255 /**
 256  * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
 257  */
 258 void __init fdt_init_reserved_mem(void)
 259 {
 260         int i;
 261
 262         /* check for overlapping reserved regions */
 263         __rmem_check_for_overlap();
 264
 265         for (i = 0; i < reserved_mem_count; i++) {
 266                 struct reserved_mem *rmem = &reserved_mem[i];
 267                 unsigned long node = rmem->fdt_node;
 268                 int len;
 269                 const __be32 *prop;
 270                 int err = 0;
 271
 272                 prop = of_get_flat_dt_prop(node, "phandle", &len);
 273                 if (!prop)
 274                         prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
 275                 if (prop)
 276                         rmem->phandle = of_read_number(prop, len/4);
 277
 278                 if (rmem->size == 0)
 279                         err = __reserved_mem_alloc_size(node, rmem->name,
 280                                                  &rmem->base, &rmem->size);
 281                 if (err == 0)
 282                         __reserved_mem_init_node(rmem);
 283         }
 284 }
 285
 286 static inline struct reserved_mem *__find_rmem(struct device_node *node)
 287 {
 288         unsigned int i;
 289
 290         if (!node->phandle)
 291                 return NULL;
 292
 293         for (i = 0; i < reserved_mem_count; i++)
 294                 if (reserved_mem[i].phandle == node->phandle)
 295                         return &reserved_mem[i];
 296         return NULL;
 297 }
 298
 299 /**
 300  * of_reserved_mem_device_init() - assign reserved memory region to given device
 301  *
 302  * This function assign memory region pointed by "memory-region" device tree
 303  * property to the given device.
 304  */
 305 int of_reserved_mem_device_init(struct device *dev)
 306 {
 307         struct reserved_mem *rmem;
 308         struct device_node *np;
 309         int ret;
 310
 311         np = of_parse_phandle(dev->of_node, "memory-region", 0);
 312         if (!np)
 313                 return -ENODEV;
 314
 315         rmem = __find_rmem(np);
 316         of_node_put(np);
 317
 318         if (!rmem || !rmem->ops || !rmem->ops->device_init)
 319                 return -EINVAL;
 320
 321         ret = rmem->ops->device_init(rmem, dev);
 322         if (ret == 0)
 323                 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
 324
 325         return ret;
 326 }
 327 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init);
 328
 329 /**
 330  * of_reserved_mem_device_release() - release reserved memory device structures
 331  *
 332  * This function releases structures allocated for memory region handling for
 333  * the given device.
 334  */
 335 void of_reserved_mem_device_release(struct device *dev)
 336 {
 337         struct reserved_mem *rmem;
 338         struct device_node *np;
 339
 340         np = of_parse_phandle(dev->of_node, "memory-region", 0);
 341         if (!np)
 342                 return;
 343
 344         rmem = __find_rmem(np);
 345         of_node_put(np);
 346
 347         if (!rmem || !rmem->ops || !rmem->ops->device_release)
 348                 return;
 349
 350         rmem->ops->device_release(rmem, dev);
 351 }
 352 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);