1 /* 2 * arch/xtensa/mm/init.c 3 * 4 * Derived from MIPS, PPC. 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file "COPYING" in the main directory of this archive 8 * for more details. 9 * 10 * Copyright (C) 2001 - 2005 Tensilica Inc. 11 * Copyright (C) 2014 Cadence Design Systems Inc. 12 * 13 * Chris Zankel <chris@zankel.net> 14 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> 15 * Marc Gauthier 16 * Kevin Chea 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/errno.h> 21 #include <linux/bootmem.h> 22 #include <linux/gfp.h> 23 #include <linux/highmem.h> 24 #include <linux/swap.h> 25 #include <linux/mman.h> 26 #include <linux/nodemask.h> 27 #include <linux/mm.h> 28 29 #include <asm/bootparam.h> 30 #include <asm/page.h> 31 #include <asm/sections.h> 32 #include <asm/sysmem.h> 33 34 struct sysmem_info sysmem __initdata; 35 36 static void __init sysmem_dump(void) 37 { 38 unsigned i; 39 40 pr_debug("Sysmem:\n"); 41 for (i = 0; i < sysmem.nr_banks; ++i) 42 pr_debug(" 0x%08lx - 0x%08lx (%ldK)\n", 43 sysmem.bank[i].start, sysmem.bank[i].end, 44 (sysmem.bank[i].end - sysmem.bank[i].start) >> 10); 45 } 46 47 /* 48 * Find bank with maximal .start such that bank.start <= start 49 */ 50 static inline struct meminfo * __init find_bank(unsigned long start) 51 { 52 unsigned i; 53 struct meminfo *it = NULL; 54 55 for (i = 0; i < sysmem.nr_banks; ++i) 56 if (sysmem.bank[i].start <= start) 57 it = sysmem.bank + i; 58 else 59 break; 60 return it; 61 } 62 63 /* 64 * Move all memory banks starting at 'from' to a new place at 'to', 65 * adjust nr_banks accordingly. 66 * Both 'from' and 'to' must be inside the sysmem.bank. 67 * 68 * Returns: 0 (success), -ENOMEM (not enough space in the sysmem.bank). 69 */ 70 static int __init move_banks(struct meminfo *to, struct meminfo *from) 71 { 72 unsigned n = sysmem.nr_banks - (from - sysmem.bank); 73 74 if (to > from && to - from + sysmem.nr_banks > SYSMEM_BANKS_MAX) 75 return -ENOMEM; 76 if (to != from) 77 memmove(to, from, n * sizeof(struct meminfo)); 78 sysmem.nr_banks += to - from; 79 return 0; 80 } 81 82 /* 83 * Add new bank to sysmem. Resulting sysmem is the union of bytes of the 84 * original sysmem and the new bank. 85 * 86 * Returns: 0 (success), < 0 (error) 87 */ 88 int __init add_sysmem_bank(unsigned long start, unsigned long end) 89 { 90 unsigned i; 91 struct meminfo *it = NULL; 92 unsigned long sz; 93 unsigned long bank_sz = 0; 94 95 if (start == end || 96 (start < end) != (PAGE_ALIGN(start) < (end & PAGE_MASK))) { 97 pr_warn("Ignoring small memory bank 0x%08lx size: %ld bytes\n", 98 start, end - start); 99 return -EINVAL; 100 } 101 102 start = PAGE_ALIGN(start); 103 end &= PAGE_MASK; 104 sz = end - start; 105 106 it = find_bank(start); 107 108 if (it) 109 bank_sz = it->end - it->start; 110 111 if (it && bank_sz >= start - it->start) { 112 if (end - it->start > bank_sz) 113 it->end = end; 114 else 115 return 0; 116 } else { 117 if (!it) 118 it = sysmem.bank; 119 else 120 ++it; 121 122 if (it - sysmem.bank < sysmem.nr_banks && 123 it->start - start <= sz) { 124 it->start = start; 125 if (it->end - it->start < sz) 126 it->end = end; 127 else 128 return 0; 129 } else { 130 if (move_banks(it + 1, it) < 0) { 131 pr_warn("Ignoring memory bank 0x%08lx size %ld bytes\n", 132 start, end - start); 133 return -EINVAL; 134 } 135 it->start = start; 136 it->end = end; 137 return 0; 138 } 139 } 140 sz = it->end - it->start; 141 for (i = it + 1 - sysmem.bank; i < sysmem.nr_banks; ++i) 142 if (sysmem.bank[i].start - it->start <= sz) { 143 if (sz < sysmem.bank[i].end - it->start) 144 it->end = sysmem.bank[i].end; 145 } else { 146 break; 147 } 148 149 move_banks(it + 1, sysmem.bank + i); 150 return 0; 151 } 152 153 /* 154 * mem_reserve(start, end, must_exist) 155 * 156 * Reserve some memory from the memory pool. 157 * If must_exist is set and a part of the region being reserved does not exist 158 * memory map is not altered. 159 * 160 * Parameters: 161 * start Start of region, 162 * end End of region, 163 * must_exist Must exist in memory pool. 164 * 165 * Returns: 166 * 0 (success) 167 * < 0 (error) 168 */ 169 170 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist) 171 { 172 struct meminfo *it; 173 struct meminfo *rm = NULL; 174 unsigned long sz; 175 unsigned long bank_sz = 0; 176 177 start = start & PAGE_MASK; 178 end = PAGE_ALIGN(end); 179 sz = end - start; 180 if (!sz) 181 return -EINVAL; 182 183 it = find_bank(start); 184 185 if (it) 186 bank_sz = it->end - it->start; 187 188 if ((!it || end - it->start > bank_sz) && must_exist) { 189 pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n", 190 start, end); 191 return -EINVAL; 192 } 193 194 if (it && start - it->start <= bank_sz) { 195 if (start == it->start) { 196 if (end - it->start < bank_sz) { 197 it->start = end; 198 return 0; 199 } else { 200 rm = it; 201 } 202 } else { 203 it->end = start; 204 if (end - it->start < bank_sz) 205 return add_sysmem_bank(end, 206 it->start + bank_sz); 207 ++it; 208 } 209 } 210 211 if (!it) 212 it = sysmem.bank; 213 214 for (; it < sysmem.bank + sysmem.nr_banks; ++it) { 215 if (it->end - start <= sz) { 216 if (!rm) 217 rm = it; 218 } else { 219 if (it->start - start < sz) 220 it->start = end; 221 break; 222 } 223 } 224 225 if (rm) 226 move_banks(rm, it); 227 228 return 0; 229 } 230 231 232 /* 233 * Initialize the bootmem system and give it all low memory we have available. 234 */ 235 236 void __init bootmem_init(void) 237 { 238 unsigned long pfn; 239 unsigned long bootmap_start, bootmap_size; 240 int i; 241 242 sysmem_dump(); 243 max_low_pfn = max_pfn = 0; 244 min_low_pfn = ~0; 245 246 for (i=0; i < sysmem.nr_banks; i++) { 247 pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT; 248 if (pfn < min_low_pfn) 249 min_low_pfn = pfn; 250 pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT; 251 if (pfn > max_pfn) 252 max_pfn = pfn; 253 } 254 255 if (min_low_pfn > max_pfn) 256 panic("No memory found!\n"); 257 258 max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? 259 max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; 260 261 /* Find an area to use for the bootmem bitmap. */ 262 263 bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn); 264 bootmap_size <<= PAGE_SHIFT; 265 bootmap_start = ~0; 266 267 for (i=0; i<sysmem.nr_banks; i++) 268 if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) { 269 bootmap_start = sysmem.bank[i].start; 270 break; 271 } 272 273 if (bootmap_start == ~0UL) 274 panic("Cannot find %ld bytes for bootmap\n", bootmap_size); 275 276 /* Reserve the bootmem bitmap area */ 277 278 mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1); 279 bootmap_size = init_bootmem_node(NODE_DATA(0), 280 bootmap_start >> PAGE_SHIFT, 281 min_low_pfn, 282 max_low_pfn); 283 284 /* Add all remaining memory pieces into the bootmem map */ 285 286 for (i = 0; i < sysmem.nr_banks; i++) { 287 if (sysmem.bank[i].start >> PAGE_SHIFT < max_low_pfn) { 288 unsigned long end = min(max_low_pfn << PAGE_SHIFT, 289 sysmem.bank[i].end); 290 free_bootmem(sysmem.bank[i].start, 291 end - sysmem.bank[i].start); 292 } 293 } 294 295 } 296 297 298 void __init zones_init(void) 299 { 300 /* All pages are DMA-able, so we put them all in the DMA zone. */ 301 unsigned long zones_size[MAX_NR_ZONES] = { 302 [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET, 303 #ifdef CONFIG_HIGHMEM 304 [ZONE_HIGHMEM] = max_pfn - max_low_pfn, 305 #endif 306 }; 307 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); 308 } 309 310 /* 311 * Initialize memory pages. 312 */ 313 314 void __init mem_init(void) 315 { 316 #ifdef CONFIG_HIGHMEM 317 unsigned long tmp; 318 319 reset_all_zones_managed_pages(); 320 for (tmp = max_low_pfn; tmp < max_pfn; tmp++) 321 free_highmem_page(pfn_to_page(tmp)); 322 #endif 323 324 max_mapnr = max_pfn - ARCH_PFN_OFFSET; 325 high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); 326 327 free_all_bootmem(); 328 329 mem_init_print_info(NULL); 330 pr_info("virtual kernel memory layout:\n" 331 #ifdef CONFIG_HIGHMEM 332 " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 333 " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n" 334 #endif 335 " vmalloc : 0x%08x - 0x%08x (%5u MB)\n" 336 " lowmem : 0x%08x - 0x%08lx (%5lu MB)\n", 337 #ifdef CONFIG_HIGHMEM 338 PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE, 339 (LAST_PKMAP*PAGE_SIZE) >> 10, 340 FIXADDR_START, FIXADDR_TOP, 341 (FIXADDR_TOP - FIXADDR_START) >> 10, 342 #endif 343 VMALLOC_START, VMALLOC_END, 344 (VMALLOC_END - VMALLOC_START) >> 20, 345 PAGE_OFFSET, PAGE_OFFSET + 346 (max_low_pfn - min_low_pfn) * PAGE_SIZE, 347 ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20); 348 } 349 350 #ifdef CONFIG_BLK_DEV_INITRD 351 extern int initrd_is_mapped; 352 353 void free_initrd_mem(unsigned long start, unsigned long end) 354 { 355 if (initrd_is_mapped) 356 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 357 } 358 #endif 359 360 void free_initmem(void) 361 { 362 free_initmem_default(-1); 363 } 364 365 static void __init parse_memmap_one(char *p) 366 { 367 char *oldp; 368 unsigned long start_at, mem_size; 369 370 if (!p) 371 return; 372 373 oldp = p; 374 mem_size = memparse(p, &p); 375 if (p == oldp) 376 return; 377 378 switch (*p) { 379 case '@': 380 start_at = memparse(p + 1, &p); 381 add_sysmem_bank(start_at, start_at + mem_size); 382 break; 383 384 case '$': 385 start_at = memparse(p + 1, &p); 386 mem_reserve(start_at, start_at + mem_size, 0); 387 break; 388 389 case 0: 390 mem_reserve(mem_size, 0, 0); 391 break; 392 393 default: 394 pr_warn("Unrecognized memmap syntax: %s\n", p); 395 break; 396 } 397 } 398 399 static int __init parse_memmap_opt(char *str) 400 { 401 while (str) { 402 char *k = strchr(str, ','); 403 404 if (k) 405 *k++ = 0; 406 407 parse_memmap_one(str); 408 str = k; 409 } 410 411 return 0; 412 } 413 early_param("memmap", parse_memmap_opt); 414