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 36 #include <asm/fixmap.h> 37 #include <asm/sections.h> 38 #include <asm/setup.h> 39 #include <asm/sizes.h> 40 #include <asm/tlb.h> 41 42 #include "mm.h" 43 44 phys_addr_t memstart_addr __read_mostly = 0; 45 46 #ifdef CONFIG_BLK_DEV_INITRD 47 static int __init early_initrd(char *p) 48 { 49 unsigned long start, size; 50 char *endp; 51 52 start = memparse(p, &endp); 53 if (*endp == ',') { 54 size = memparse(endp + 1, NULL); 55 56 initrd_start = (unsigned long)__va(start); 57 initrd_end = (unsigned long)__va(start + size); 58 } 59 return 0; 60 } 61 early_param("initrd", early_initrd); 62 #endif 63 64 /* 65 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It 66 * currently assumes that for memory starting above 4G, 32-bit devices will 67 * use a DMA offset. 68 */ 69 static phys_addr_t max_zone_dma_phys(void) 70 { 71 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32); 72 return min(offset + (1ULL << 32), memblock_end_of_DRAM()); 73 } 74 75 static void __init zone_sizes_init(unsigned long min, unsigned long max) 76 { 77 struct memblock_region *reg; 78 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 79 unsigned long max_dma = min; 80 81 memset(zone_size, 0, sizeof(zone_size)); 82 83 /* 4GB maximum for 32-bit only capable devices */ 84 if (IS_ENABLED(CONFIG_ZONE_DMA)) { 85 max_dma = PFN_DOWN(max_zone_dma_phys()); 86 zone_size[ZONE_DMA] = max_dma - min; 87 } 88 zone_size[ZONE_NORMAL] = max - max_dma; 89 90 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 91 92 for_each_memblock(memory, reg) { 93 unsigned long start = memblock_region_memory_base_pfn(reg); 94 unsigned long end = memblock_region_memory_end_pfn(reg); 95 96 if (start >= max) 97 continue; 98 99 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) { 100 unsigned long dma_end = min(end, max_dma); 101 zhole_size[ZONE_DMA] -= dma_end - start; 102 } 103 104 if (end > max_dma) { 105 unsigned long normal_end = min(end, max); 106 unsigned long normal_start = max(start, max_dma); 107 zhole_size[ZONE_NORMAL] -= normal_end - normal_start; 108 } 109 } 110 111 free_area_init_node(0, zone_size, min, zhole_size); 112 } 113 114 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 115 int pfn_valid(unsigned long pfn) 116 { 117 return memblock_is_memory(pfn << PAGE_SHIFT); 118 } 119 EXPORT_SYMBOL(pfn_valid); 120 #endif 121 122 #ifndef CONFIG_SPARSEMEM 123 static void arm64_memory_present(void) 124 { 125 } 126 #else 127 static void arm64_memory_present(void) 128 { 129 struct memblock_region *reg; 130 131 for_each_memblock(memory, reg) 132 memory_present(0, memblock_region_memory_base_pfn(reg), 133 memblock_region_memory_end_pfn(reg)); 134 } 135 #endif 136 137 void __init arm64_memblock_init(void) 138 { 139 phys_addr_t dma_phys_limit = 0; 140 141 /* 142 * Register the kernel text, kernel data, initrd, and initial 143 * pagetables with memblock. 144 */ 145 memblock_reserve(__pa(_text), _end - _text); 146 #ifdef CONFIG_BLK_DEV_INITRD 147 if (initrd_start) 148 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start); 149 #endif 150 151 early_init_fdt_scan_reserved_mem(); 152 153 /* 4GB maximum for 32-bit only capable devices */ 154 if (IS_ENABLED(CONFIG_ZONE_DMA)) 155 dma_phys_limit = max_zone_dma_phys(); 156 dma_contiguous_reserve(dma_phys_limit); 157 158 memblock_allow_resize(); 159 memblock_dump_all(); 160 } 161 162 void __init bootmem_init(void) 163 { 164 unsigned long min, max; 165 166 min = PFN_UP(memblock_start_of_DRAM()); 167 max = PFN_DOWN(memblock_end_of_DRAM()); 168 169 /* 170 * Sparsemem tries to allocate bootmem in memory_present(), so must be 171 * done after the fixed reservations. 172 */ 173 arm64_memory_present(); 174 175 sparse_init(); 176 zone_sizes_init(min, max); 177 178 high_memory = __va((max << PAGE_SHIFT) - 1) + 1; 179 max_pfn = max_low_pfn = max; 180 } 181 182 #ifndef CONFIG_SPARSEMEM_VMEMMAP 183 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) 184 { 185 struct page *start_pg, *end_pg; 186 unsigned long pg, pgend; 187 188 /* 189 * Convert start_pfn/end_pfn to a struct page pointer. 190 */ 191 start_pg = pfn_to_page(start_pfn - 1) + 1; 192 end_pg = pfn_to_page(end_pfn - 1) + 1; 193 194 /* 195 * Convert to physical addresses, and round start upwards and end 196 * downwards. 197 */ 198 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 199 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 200 201 /* 202 * If there are free pages between these, free the section of the 203 * memmap array. 204 */ 205 if (pg < pgend) 206 free_bootmem(pg, pgend - pg); 207 } 208 209 /* 210 * The mem_map array can get very big. Free the unused area of the memory map. 211 */ 212 static void __init free_unused_memmap(void) 213 { 214 unsigned long start, prev_end = 0; 215 struct memblock_region *reg; 216 217 for_each_memblock(memory, reg) { 218 start = __phys_to_pfn(reg->base); 219 220 #ifdef CONFIG_SPARSEMEM 221 /* 222 * Take care not to free memmap entries that don't exist due 223 * to SPARSEMEM sections which aren't present. 224 */ 225 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); 226 #endif 227 /* 228 * If we had a previous bank, and there is a space between the 229 * current bank and the previous, free it. 230 */ 231 if (prev_end && prev_end < start) 232 free_memmap(prev_end, start); 233 234 /* 235 * Align up here since the VM subsystem insists that the 236 * memmap entries are valid from the bank end aligned to 237 * MAX_ORDER_NR_PAGES. 238 */ 239 prev_end = ALIGN(start + __phys_to_pfn(reg->size), 240 MAX_ORDER_NR_PAGES); 241 } 242 243 #ifdef CONFIG_SPARSEMEM 244 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) 245 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); 246 #endif 247 } 248 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ 249 250 /* 251 * mem_init() marks the free areas in the mem_map and tells us how much memory 252 * is free. This is done after various parts of the system have claimed their 253 * memory after the kernel image. 254 */ 255 void __init mem_init(void) 256 { 257 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map; 258 259 #ifndef CONFIG_SPARSEMEM_VMEMMAP 260 free_unused_memmap(); 261 #endif 262 /* this will put all unused low memory onto the freelists */ 263 free_all_bootmem(); 264 265 mem_init_print_info(NULL); 266 267 #define MLK(b, t) b, t, ((t) - (b)) >> 10 268 #define MLM(b, t) b, t, ((t) - (b)) >> 20 269 #define MLG(b, t) b, t, ((t) - (b)) >> 30 270 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 271 272 pr_notice("Virtual kernel memory layout:\n" 273 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n" 274 #ifdef CONFIG_SPARSEMEM_VMEMMAP 275 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n" 276 " 0x%16lx - 0x%16lx (%6ld MB actual)\n" 277 #endif 278 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n" 279 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n" 280 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n" 281 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n" 282 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n" 283 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n" 284 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n", 285 MLG(VMALLOC_START, VMALLOC_END), 286 #ifdef CONFIG_SPARSEMEM_VMEMMAP 287 MLG((unsigned long)vmemmap, 288 (unsigned long)vmemmap + VMEMMAP_SIZE), 289 MLM((unsigned long)virt_to_page(PAGE_OFFSET), 290 (unsigned long)virt_to_page(high_memory)), 291 #endif 292 MLM((unsigned long)PCI_IOBASE, (unsigned long)PCI_IOBASE + SZ_16M), 293 MLK(FIXADDR_START, FIXADDR_TOP), 294 MLM(MODULES_VADDR, MODULES_END), 295 MLM(PAGE_OFFSET, (unsigned long)high_memory), 296 MLK_ROUNDUP(__init_begin, __init_end), 297 MLK_ROUNDUP(_text, _etext), 298 MLK_ROUNDUP(_sdata, _edata)); 299 300 #undef MLK 301 #undef MLM 302 #undef MLK_ROUNDUP 303 304 /* 305 * Check boundaries twice: Some fundamental inconsistencies can be 306 * detected at build time already. 307 */ 308 #ifdef CONFIG_COMPAT 309 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); 310 #endif 311 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 312 BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 313 314 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { 315 extern int sysctl_overcommit_memory; 316 /* 317 * On a machine this small we won't get anywhere without 318 * overcommit, so turn it on by default. 319 */ 320 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 321 } 322 } 323 324 void free_initmem(void) 325 { 326 free_initmem_default(0); 327 } 328 329 #ifdef CONFIG_BLK_DEV_INITRD 330 331 static int keep_initrd; 332 333 void free_initrd_mem(unsigned long start, unsigned long end) 334 { 335 if (!keep_initrd) 336 free_reserved_area((void *)start, (void *)end, 0, "initrd"); 337 } 338 339 static int __init keepinitrd_setup(char *__unused) 340 { 341 keep_initrd = 1; 342 return 1; 343 } 344 345 __setup("keepinitrd", keepinitrd_setup); 346 #endif 347