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/sections.h> 39 #include <asm/setup.h> 40 #include <asm/sizes.h> 41 #include <asm/tlb.h> 42 43 #include "mm.h" 44 45 phys_addr_t memstart_addr __read_mostly = 0; 46 47 #ifdef CONFIG_BLK_DEV_INITRD 48 static int __init early_initrd(char *p) 49 { 50 unsigned long start, size; 51 char *endp; 52 53 start = memparse(p, &endp); 54 if (*endp == ',') { 55 size = memparse(endp + 1, NULL); 56 57 initrd_start = (unsigned long)__va(start); 58 initrd_end = (unsigned long)__va(start + size); 59 } 60 return 0; 61 } 62 early_param("initrd", early_initrd); 63 #endif 64 65 /* 66 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It 67 * currently assumes that for memory starting above 4G, 32-bit devices will 68 * use a DMA offset. 69 */ 70 static phys_addr_t max_zone_dma_phys(void) 71 { 72 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32); 73 return min(offset + (1ULL << 32), memblock_end_of_DRAM()); 74 } 75 76 static void __init zone_sizes_init(unsigned long min, unsigned long max) 77 { 78 struct memblock_region *reg; 79 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 80 unsigned long max_dma = min; 81 82 memset(zone_size, 0, sizeof(zone_size)); 83 84 /* 4GB maximum for 32-bit only capable devices */ 85 if (IS_ENABLED(CONFIG_ZONE_DMA)) { 86 max_dma = PFN_DOWN(max_zone_dma_phys()); 87 zone_size[ZONE_DMA] = max_dma - min; 88 } 89 zone_size[ZONE_NORMAL] = max - max_dma; 90 91 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 92 93 for_each_memblock(memory, reg) { 94 unsigned long start = memblock_region_memory_base_pfn(reg); 95 unsigned long end = memblock_region_memory_end_pfn(reg); 96 97 if (start >= max) 98 continue; 99 100 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) { 101 unsigned long dma_end = min(end, max_dma); 102 zhole_size[ZONE_DMA] -= dma_end - start; 103 } 104 105 if (end > max_dma) { 106 unsigned long normal_end = min(end, max); 107 unsigned long normal_start = max(start, max_dma); 108 zhole_size[ZONE_NORMAL] -= normal_end - normal_start; 109 } 110 } 111 112 free_area_init_node(0, zone_size, min, zhole_size); 113 } 114 115 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 116 int pfn_valid(unsigned long pfn) 117 { 118 return memblock_is_memory(pfn << PAGE_SHIFT); 119 } 120 EXPORT_SYMBOL(pfn_valid); 121 #endif 122 123 #ifndef CONFIG_SPARSEMEM 124 static void arm64_memory_present(void) 125 { 126 } 127 #else 128 static void arm64_memory_present(void) 129 { 130 struct memblock_region *reg; 131 132 for_each_memblock(memory, reg) 133 memory_present(0, memblock_region_memory_base_pfn(reg), 134 memblock_region_memory_end_pfn(reg)); 135 } 136 #endif 137 138 void __init arm64_memblock_init(void) 139 { 140 phys_addr_t dma_phys_limit = 0; 141 142 /* 143 * Register the kernel text, kernel data, initrd, and initial 144 * pagetables with memblock. 145 */ 146 memblock_reserve(__pa(_text), _end - _text); 147 #ifdef CONFIG_BLK_DEV_INITRD 148 if (initrd_start) 149 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start); 150 #endif 151 152 if (!efi_enabled(EFI_MEMMAP)) 153 early_init_fdt_scan_reserved_mem(); 154 155 /* 4GB maximum for 32-bit only capable devices */ 156 if (IS_ENABLED(CONFIG_ZONE_DMA)) 157 dma_phys_limit = max_zone_dma_phys(); 158 dma_contiguous_reserve(dma_phys_limit); 159 160 memblock_allow_resize(); 161 memblock_dump_all(); 162 } 163 164 void __init bootmem_init(void) 165 { 166 unsigned long min, max; 167 168 min = PFN_UP(memblock_start_of_DRAM()); 169 max = PFN_DOWN(memblock_end_of_DRAM()); 170 171 /* 172 * Sparsemem tries to allocate bootmem in memory_present(), so must be 173 * done after the fixed reservations. 174 */ 175 arm64_memory_present(); 176 177 sparse_init(); 178 zone_sizes_init(min, max); 179 180 high_memory = __va((max << PAGE_SHIFT) - 1) + 1; 181 max_pfn = max_low_pfn = max; 182 } 183 184 #ifndef CONFIG_SPARSEMEM_VMEMMAP 185 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) 186 { 187 struct page *start_pg, *end_pg; 188 unsigned long pg, pgend; 189 190 /* 191 * Convert start_pfn/end_pfn to a struct page pointer. 192 */ 193 start_pg = pfn_to_page(start_pfn - 1) + 1; 194 end_pg = pfn_to_page(end_pfn - 1) + 1; 195 196 /* 197 * Convert to physical addresses, and round start upwards and end 198 * downwards. 199 */ 200 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 201 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 202 203 /* 204 * If there are free pages between these, free the section of the 205 * memmap array. 206 */ 207 if (pg < pgend) 208 free_bootmem(pg, pgend - pg); 209 } 210 211 /* 212 * The mem_map array can get very big. Free the unused area of the memory map. 213 */ 214 static void __init free_unused_memmap(void) 215 { 216 unsigned long start, prev_end = 0; 217 struct memblock_region *reg; 218 219 for_each_memblock(memory, reg) { 220 start = __phys_to_pfn(reg->base); 221 222 #ifdef CONFIG_SPARSEMEM 223 /* 224 * Take care not to free memmap entries that don't exist due 225 * to SPARSEMEM sections which aren't present. 226 */ 227 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); 228 #endif 229 /* 230 * If we had a previous bank, and there is a space between the 231 * current bank and the previous, free it. 232 */ 233 if (prev_end && prev_end < start) 234 free_memmap(prev_end, start); 235 236 /* 237 * Align up here since the VM subsystem insists that the 238 * memmap entries are valid from the bank end aligned to 239 * MAX_ORDER_NR_PAGES. 240 */ 241 prev_end = ALIGN(start + __phys_to_pfn(reg->size), 242 MAX_ORDER_NR_PAGES); 243 } 244 245 #ifdef CONFIG_SPARSEMEM 246 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) 247 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); 248 #endif 249 } 250 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ 251 252 /* 253 * mem_init() marks the free areas in the mem_map and tells us how much memory 254 * is free. This is done after various parts of the system have claimed their 255 * memory after the kernel image. 256 */ 257 void __init mem_init(void) 258 { 259 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map; 260 261 #ifndef CONFIG_SPARSEMEM_VMEMMAP 262 free_unused_memmap(); 263 #endif 264 /* this will put all unused low memory onto the freelists */ 265 free_all_bootmem(); 266 267 mem_init_print_info(NULL); 268 269 #define MLK(b, t) b, t, ((t) - (b)) >> 10 270 #define MLM(b, t) b, t, ((t) - (b)) >> 20 271 #define MLG(b, t) b, t, ((t) - (b)) >> 30 272 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 273 274 pr_notice("Virtual kernel memory layout:\n" 275 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n" 276 #ifdef CONFIG_SPARSEMEM_VMEMMAP 277 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n" 278 " 0x%16lx - 0x%16lx (%6ld MB actual)\n" 279 #endif 280 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n" 281 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n" 282 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n" 283 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n" 284 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n" 285 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n" 286 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n", 287 MLG(VMALLOC_START, VMALLOC_END), 288 #ifdef CONFIG_SPARSEMEM_VMEMMAP 289 MLG((unsigned long)vmemmap, 290 (unsigned long)vmemmap + VMEMMAP_SIZE), 291 MLM((unsigned long)virt_to_page(PAGE_OFFSET), 292 (unsigned long)virt_to_page(high_memory)), 293 #endif 294 MLM((unsigned long)PCI_IOBASE, (unsigned long)PCI_IOBASE + SZ_16M), 295 MLK(FIXADDR_START, FIXADDR_TOP), 296 MLM(MODULES_VADDR, MODULES_END), 297 MLM(PAGE_OFFSET, (unsigned long)high_memory), 298 MLK_ROUNDUP(__init_begin, __init_end), 299 MLK_ROUNDUP(_text, _etext), 300 MLK_ROUNDUP(_sdata, _edata)); 301 302 #undef MLK 303 #undef MLM 304 #undef MLK_ROUNDUP 305 306 /* 307 * Check boundaries twice: Some fundamental inconsistencies can be 308 * detected at build time already. 309 */ 310 #ifdef CONFIG_COMPAT 311 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); 312 #endif 313 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 314 BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 315 316 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { 317 extern int sysctl_overcommit_memory; 318 /* 319 * On a machine this small we won't get anywhere without 320 * overcommit, so turn it on by default. 321 */ 322 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 323 } 324 } 325 326 void free_initmem(void) 327 { 328 free_initmem_default(0); 329 } 330 331 #ifdef CONFIG_BLK_DEV_INITRD 332 333 static int keep_initrd; 334 335 void free_initrd_mem(unsigned long start, unsigned long end) 336 { 337 if (!keep_initrd) 338 free_reserved_area((void *)start, (void *)end, 0, "initrd"); 339 } 340 341 static int __init keepinitrd_setup(char *__unused) 342 { 343 keep_initrd = 1; 344 return 1; 345 } 346 347 __setup("keepinitrd", keepinitrd_setup); 348 #endif 349