1 /* 2 * Based on arch/arm/mm/init.c 3 * 4 * Copyright (C) 1995-2005 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/kernel.h> 21 #include <linux/export.h> 22 #include <linux/errno.h> 23 #include <linux/swap.h> 24 #include <linux/init.h> 25 #include <linux/bootmem.h> 26 #include <linux/mman.h> 27 #include <linux/nodemask.h> 28 #include <linux/initrd.h> 29 #include <linux/gfp.h> 30 #include <linux/memblock.h> 31 #include <linux/sort.h> 32 #include <linux/of_fdt.h> 33 #include <linux/dma-mapping.h> 34 #include <linux/dma-contiguous.h> 35 #include <linux/efi.h> 36 37 #include <asm/fixmap.h> 38 #include <asm/memory.h> 39 #include <asm/sections.h> 40 #include <asm/setup.h> 41 #include <asm/sizes.h> 42 #include <asm/tlb.h> 43 #include <asm/alternative.h> 44 45 #include "mm.h" 46 47 phys_addr_t memstart_addr __read_mostly = 0; 48 49 #ifdef CONFIG_BLK_DEV_INITRD 50 static int __init early_initrd(char *p) 51 { 52 unsigned long start, size; 53 char *endp; 54 55 start = memparse(p, &endp); 56 if (*endp == ',') { 57 size = memparse(endp + 1, NULL); 58 59 initrd_start = (unsigned long)__va(start); 60 initrd_end = (unsigned long)__va(start + size); 61 } 62 return 0; 63 } 64 early_param("initrd", early_initrd); 65 #endif 66 67 /* 68 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It 69 * currently assumes that for memory starting above 4G, 32-bit devices will 70 * use a DMA offset. 71 */ 72 static phys_addr_t max_zone_dma_phys(void) 73 { 74 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32); 75 return min(offset + (1ULL << 32), memblock_end_of_DRAM()); 76 } 77 78 static void __init zone_sizes_init(unsigned long min, unsigned long max) 79 { 80 struct memblock_region *reg; 81 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 82 unsigned long max_dma = min; 83 84 memset(zone_size, 0, sizeof(zone_size)); 85 86 /* 4GB maximum for 32-bit only capable devices */ 87 if (IS_ENABLED(CONFIG_ZONE_DMA)) { 88 max_dma = PFN_DOWN(max_zone_dma_phys()); 89 zone_size[ZONE_DMA] = max_dma - min; 90 } 91 zone_size[ZONE_NORMAL] = max - max_dma; 92 93 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 94 95 for_each_memblock(memory, reg) { 96 unsigned long start = memblock_region_memory_base_pfn(reg); 97 unsigned long end = memblock_region_memory_end_pfn(reg); 98 99 if (start >= max) 100 continue; 101 102 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) { 103 unsigned long dma_end = min(end, max_dma); 104 zhole_size[ZONE_DMA] -= dma_end - start; 105 } 106 107 if (end > max_dma) { 108 unsigned long normal_end = min(end, max); 109 unsigned long normal_start = max(start, max_dma); 110 zhole_size[ZONE_NORMAL] -= normal_end - normal_start; 111 } 112 } 113 114 free_area_init_node(0, zone_size, min, zhole_size); 115 } 116 117 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 118 int pfn_valid(unsigned long pfn) 119 { 120 return memblock_is_memory(pfn << PAGE_SHIFT); 121 } 122 EXPORT_SYMBOL(pfn_valid); 123 #endif 124 125 #ifndef CONFIG_SPARSEMEM 126 static void arm64_memory_present(void) 127 { 128 } 129 #else 130 static void arm64_memory_present(void) 131 { 132 struct memblock_region *reg; 133 134 for_each_memblock(memory, reg) 135 memory_present(0, memblock_region_memory_base_pfn(reg), 136 memblock_region_memory_end_pfn(reg)); 137 } 138 #endif 139 140 static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX; 141 142 /* 143 * Limit the memory size that was specified via FDT. 144 */ 145 static int __init early_mem(char *p) 146 { 147 if (!p) 148 return 1; 149 150 memory_limit = memparse(p, &p) & PAGE_MASK; 151 pr_notice("Memory limited to %lldMB\n", memory_limit >> 20); 152 153 return 0; 154 } 155 early_param("mem", early_mem); 156 157 void __init arm64_memblock_init(void) 158 { 159 phys_addr_t dma_phys_limit = 0; 160 161 memblock_enforce_memory_limit(memory_limit); 162 163 /* 164 * Register the kernel text, kernel data, initrd, and initial 165 * pagetables with memblock. 166 */ 167 memblock_reserve(__pa(_text), _end - _text); 168 #ifdef CONFIG_BLK_DEV_INITRD 169 if (initrd_start) 170 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start); 171 #endif 172 173 early_init_fdt_scan_reserved_mem(); 174 175 /* 4GB maximum for 32-bit only capable devices */ 176 if (IS_ENABLED(CONFIG_ZONE_DMA)) 177 dma_phys_limit = max_zone_dma_phys(); 178 dma_contiguous_reserve(dma_phys_limit); 179 180 memblock_allow_resize(); 181 memblock_dump_all(); 182 } 183 184 void __init bootmem_init(void) 185 { 186 unsigned long min, max; 187 188 min = PFN_UP(memblock_start_of_DRAM()); 189 max = PFN_DOWN(memblock_end_of_DRAM()); 190 191 /* 192 * Sparsemem tries to allocate bootmem in memory_present(), so must be 193 * done after the fixed reservations. 194 */ 195 arm64_memory_present(); 196 197 sparse_init(); 198 zone_sizes_init(min, max); 199 200 high_memory = __va((max << PAGE_SHIFT) - 1) + 1; 201 max_pfn = max_low_pfn = max; 202 } 203 204 #ifndef CONFIG_SPARSEMEM_VMEMMAP 205 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) 206 { 207 struct page *start_pg, *end_pg; 208 unsigned long pg, pgend; 209 210 /* 211 * Convert start_pfn/end_pfn to a struct page pointer. 212 */ 213 start_pg = pfn_to_page(start_pfn - 1) + 1; 214 end_pg = pfn_to_page(end_pfn - 1) + 1; 215 216 /* 217 * Convert to physical addresses, and round start upwards and end 218 * downwards. 219 */ 220 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 221 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 222 223 /* 224 * If there are free pages between these, free the section of the 225 * memmap array. 226 */ 227 if (pg < pgend) 228 free_bootmem(pg, pgend - pg); 229 } 230 231 /* 232 * The mem_map array can get very big. Free the unused area of the memory map. 233 */ 234 static void __init free_unused_memmap(void) 235 { 236 unsigned long start, prev_end = 0; 237 struct memblock_region *reg; 238 239 for_each_memblock(memory, reg) { 240 start = __phys_to_pfn(reg->base); 241 242 #ifdef CONFIG_SPARSEMEM 243 /* 244 * Take care not to free memmap entries that don't exist due 245 * to SPARSEMEM sections which aren't present. 246 */ 247 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); 248 #endif 249 /* 250 * If we had a previous bank, and there is a space between the 251 * current bank and the previous, free it. 252 */ 253 if (prev_end && prev_end < start) 254 free_memmap(prev_end, start); 255 256 /* 257 * Align up here since the VM subsystem insists that the 258 * memmap entries are valid from the bank end aligned to 259 * MAX_ORDER_NR_PAGES. 260 */ 261 prev_end = ALIGN(start + __phys_to_pfn(reg->size), 262 MAX_ORDER_NR_PAGES); 263 } 264 265 #ifdef CONFIG_SPARSEMEM 266 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) 267 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); 268 #endif 269 } 270 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ 271 272 /* 273 * mem_init() marks the free areas in the mem_map and tells us how much memory 274 * is free. This is done after various parts of the system have claimed their 275 * memory after the kernel image. 276 */ 277 void __init mem_init(void) 278 { 279 set_max_mapnr(pfn_to_page(max_pfn) - mem_map); 280 281 #ifndef CONFIG_SPARSEMEM_VMEMMAP 282 free_unused_memmap(); 283 #endif 284 /* this will put all unused low memory onto the freelists */ 285 free_all_bootmem(); 286 287 mem_init_print_info(NULL); 288 289 #define MLK(b, t) b, t, ((t) - (b)) >> 10 290 #define MLM(b, t) b, t, ((t) - (b)) >> 20 291 #define MLG(b, t) b, t, ((t) - (b)) >> 30 292 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 293 294 pr_notice("Virtual kernel memory layout:\n" 295 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n" 296 #ifdef CONFIG_SPARSEMEM_VMEMMAP 297 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n" 298 " 0x%16lx - 0x%16lx (%6ld MB actual)\n" 299 #endif 300 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n" 301 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n" 302 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n" 303 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n" 304 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n" 305 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n" 306 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n", 307 MLG(VMALLOC_START, VMALLOC_END), 308 #ifdef CONFIG_SPARSEMEM_VMEMMAP 309 MLG((unsigned long)vmemmap, 310 (unsigned long)vmemmap + VMEMMAP_SIZE), 311 MLM((unsigned long)virt_to_page(PAGE_OFFSET), 312 (unsigned long)virt_to_page(high_memory)), 313 #endif 314 MLK(FIXADDR_START, FIXADDR_TOP), 315 MLM(PCI_IO_START, PCI_IO_END), 316 MLM(MODULES_VADDR, MODULES_END), 317 MLM(PAGE_OFFSET, (unsigned long)high_memory), 318 MLK_ROUNDUP(__init_begin, __init_end), 319 MLK_ROUNDUP(_text, _etext), 320 MLK_ROUNDUP(_sdata, _edata)); 321 322 #undef MLK 323 #undef MLM 324 #undef MLK_ROUNDUP 325 326 /* 327 * Check boundaries twice: Some fundamental inconsistencies can be 328 * detected at build time already. 329 */ 330 #ifdef CONFIG_COMPAT 331 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); 332 #endif 333 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 334 BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 335 336 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { 337 extern int sysctl_overcommit_memory; 338 /* 339 * On a machine this small we won't get anywhere without 340 * overcommit, so turn it on by default. 341 */ 342 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 343 } 344 } 345 346 void free_initmem(void) 347 { 348 fixup_init(); 349 free_initmem_default(0); 350 free_alternatives_memory(); 351 } 352 353 #ifdef CONFIG_BLK_DEV_INITRD 354 355 static int keep_initrd; 356 357 void free_initrd_mem(unsigned long start, unsigned long end) 358 { 359 if (!keep_initrd) 360 free_reserved_area((void *)start, (void *)end, 0, "initrd"); 361 } 362 363 static int __init keepinitrd_setup(char *__unused) 364 { 365 keep_initrd = 1; 366 return 1; 367 } 368 369 __setup("keepinitrd", keepinitrd_setup); 370 #endif 371