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 <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                 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("Reserved memory: 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("Reserved memory: allocated memory for '%s' node: base %pa, size %ld 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("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n",
 169                                 uname, &base, (unsigned long)size / SZ_1M);
 170         }
 171
 172         if (base == 0) {
 173                 pr_info("Reserved memory: failed to allocate memory for node '%s'\n",
 174                         uname);
 175                 return -ENOMEM;
 176         }
 177
 178         *res_base = base;
 179         *res_size = size;
 180
 181         return 0;
 182 }
 183
 184 static const struct of_device_id __rmem_of_table_sentinel
 185         __used __section(__reservedmem_of_table_end);
 186
 187 /**
 188  * res_mem_init_node() - call region specific reserved memory init code
 189  */
 190 static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
 191 {
 192         extern const struct of_device_id __reservedmem_of_table[];
 193         const struct of_device_id *i;
 194
 195         for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
 196                 reservedmem_of_init_fn initfn = i->data;
 197                 const char *compat = i->compatible;
 198
 199                 if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
 200                         continue;
 201
 202                 if (initfn(rmem) == 0) {
 203                         pr_info("Reserved memory: initialized node %s, compatible id %s\n",
 204                                 rmem->name, compat);
 205                         return 0;
 206                 }
 207         }
 208         return -ENOENT;
 209 }
 210
 211 static int __init __rmem_cmp(const void *a, const void *b)
 212 {
 213         const struct reserved_mem *ra = a, *rb = b;
 214
 215         if (ra->base < rb->base)
 216                 return -1;
 217
 218         if (ra->base > rb->base)
 219                 return 1;
 220
 221         /*
 222          * Put the dynamic allocations (address == 0, size == 0) before static
 223          * allocations at address 0x0 so that overlap detection works
 224          * correctly.
 225          */
 226         if (ra->size < rb->size)
 227                 return -1;
 228         if (ra->size > rb->size)
 229                 return 1;
 230
 231         return 0;
 232 }
 233
 234 static void __init __rmem_check_for_overlap(void)
 235 {
 236         int i;
 237
 238         if (reserved_mem_count < 2)
 239                 return;
 240
 241         sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
 242              __rmem_cmp, NULL);
 243         for (i = 0; i < reserved_mem_count - 1; i++) {
 244                 struct reserved_mem *this, *next;
 245
 246                 this = &reserved_mem[i];
 247                 next = &reserved_mem[i + 1];
 248
 249                 if (this->base + this->size > next->base) {
 250                         phys_addr_t this_end, next_end;
 251
 252                         this_end = this->base + this->size;
 253                         next_end = next->base + next->size;
 254                         pr_err("Reserved memory: OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
 255                                this->name, &this->base, &this_end,
 256                                next->name, &next->base, &next_end);
 257                 }
 258         }
 259 }
 260
 261 /**
 262  * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
 263  */
 264 void __init fdt_init_reserved_mem(void)
 265 {
 266         int i;
 267
 268         /* check for overlapping reserved regions */
 269         __rmem_check_for_overlap();
 270
 271         for (i = 0; i < reserved_mem_count; i++) {
 272                 struct reserved_mem *rmem = &reserved_mem[i];
 273                 unsigned long node = rmem->fdt_node;
 274                 int len;
 275                 const __be32 *prop;
 276                 int err = 0;
 277
 278                 prop = of_get_flat_dt_prop(node, "phandle", &len);
 279                 if (!prop)
 280                         prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
 281                 if (prop)
 282                         rmem->phandle = of_read_number(prop, len/4);
 283
 284                 if (rmem->size == 0)
 285                         err = __reserved_mem_alloc_size(node, rmem->name,
 286                                                  &rmem->base, &rmem->size);
 287                 if (err == 0)
 288                         __reserved_mem_init_node(rmem);
 289         }
 290 }
 291
 292 static inline struct reserved_mem *__find_rmem(struct device_node *node)
 293 {
 294         unsigned int i;
 295
 296         if (!node->phandle)
 297                 return NULL;
 298
 299         for (i = 0; i < reserved_mem_count; i++)
 300                 if (reserved_mem[i].phandle == node->phandle)
 301                         return &reserved_mem[i];
 302         return NULL;
 303 }
 304
 305 /**
 306  * of_reserved_mem_device_init() - assign reserved memory region to given device
 307  *
 308  * This function assign memory region pointed by "memory-region" device tree
 309  * property to the given device.
 310  */
 311 int of_reserved_mem_device_init(struct device *dev)
 312 {
 313         struct reserved_mem *rmem;
 314         struct device_node *np;
 315         int ret;
 316
 317         np = of_parse_phandle(dev->of_node, "memory-region", 0);
 318         if (!np)
 319                 return -ENODEV;
 320
 321         rmem = __find_rmem(np);
 322         of_node_put(np);
 323
 324         if (!rmem || !rmem->ops || !rmem->ops->device_init)
 325                 return -EINVAL;
 326
 327         ret = rmem->ops->device_init(rmem, dev);
 328         if (ret == 0)
 329                 dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
 330
 331         return ret;
 332 }
 333 EXPORT_SYMBOL_GPL(of_reserved_mem_device_init);
 334
 335 /**
 336  * of_reserved_mem_device_release() - release reserved memory device structures
 337  *
 338  * This function releases structures allocated for memory region handling for
 339  * the given device.
 340  */
 341 void of_reserved_mem_device_release(struct device *dev)
 342 {
 343         struct reserved_mem *rmem;
 344         struct device_node *np;
 345
 346         np = of_parse_phandle(dev->of_node, "memory-region", 0);
 347         if (!np)
 348                 return;
 349
 350         rmem = __find_rmem(np);
 351         of_node_put(np);
 352
 353         if (!rmem || !rmem->ops || !rmem->ops->device_release)
 354                 return;
 355
 356         rmem->ops->device_release(rmem, dev);
 357 }
 358 EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);