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 #include <linux/swiotlb.h> 37 38 #include <asm/fixmap.h> 39 #include <asm/memory.h> 40 #include <asm/sections.h> 41 #include <asm/setup.h> 42 #include <asm/sizes.h> 43 #include <asm/tlb.h> 44 #include <asm/alternative.h> 45 46 #include "mm.h" 47 48 phys_addr_t memstart_addr __read_mostly = 0; 49 phys_addr_t arm64_dma_phys_limit __read_mostly; 50 51 #ifdef CONFIG_BLK_DEV_INITRD 52 static int __init early_initrd(char *p) 53 { 54 unsigned long start, size; 55 char *endp; 56 57 start = memparse(p, &endp); 58 if (*endp == ',') { 59 size = memparse(endp + 1, NULL); 60 61 initrd_start = (unsigned long)__va(start); 62 initrd_end = (unsigned long)__va(start + size); 63 } 64 return 0; 65 } 66 early_param("initrd", early_initrd); 67 #endif 68 69 /* 70 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It 71 * currently assumes that for memory starting above 4G, 32-bit devices will 72 * use a DMA offset. 73 */ 74 static phys_addr_t __init max_zone_dma_phys(void) 75 { 76 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32); 77 return min(offset + (1ULL << 32), memblock_end_of_DRAM()); 78 } 79 80 static void __init zone_sizes_init(unsigned long min, unsigned long max) 81 { 82 struct memblock_region *reg; 83 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 84 unsigned long max_dma = min; 85 86 memset(zone_size, 0, sizeof(zone_size)); 87 88 /* 4GB maximum for 32-bit only capable devices */ 89 #ifdef CONFIG_ZONE_DMA 90 max_dma = PFN_DOWN(arm64_dma_phys_limit); 91 zone_size[ZONE_DMA] = max_dma - min; 92 #endif 93 zone_size[ZONE_NORMAL] = max - max_dma; 94 95 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 96 97 for_each_memblock(memory, reg) { 98 unsigned long start = memblock_region_memory_base_pfn(reg); 99 unsigned long end = memblock_region_memory_end_pfn(reg); 100 101 if (start >= max) 102 continue; 103 104 #ifdef CONFIG_ZONE_DMA 105 if (start < max_dma) { 106 unsigned long dma_end = min(end, max_dma); 107 zhole_size[ZONE_DMA] -= dma_end - start; 108 } 109 #endif 110 if (end > max_dma) { 111 unsigned long normal_end = min(end, max); 112 unsigned long normal_start = max(start, max_dma); 113 zhole_size[ZONE_NORMAL] -= normal_end - normal_start; 114 } 115 } 116 117 free_area_init_node(0, zone_size, min, zhole_size); 118 } 119 120 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 121 int pfn_valid(unsigned long pfn) 122 { 123 return memblock_is_map_memory(pfn << PAGE_SHIFT); 124 } 125 EXPORT_SYMBOL(pfn_valid); 126 #endif 127 128 #ifndef CONFIG_SPARSEMEM 129 static void __init arm64_memory_present(void) 130 { 131 } 132 #else 133 static void __init arm64_memory_present(void) 134 { 135 struct memblock_region *reg; 136 137 for_each_memblock(memory, reg) 138 memory_present(0, memblock_region_memory_base_pfn(reg), 139 memblock_region_memory_end_pfn(reg)); 140 } 141 #endif 142 143 static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX; 144 145 /* 146 * Limit the memory size that was specified via FDT. 147 */ 148 static int __init early_mem(char *p) 149 { 150 if (!p) 151 return 1; 152 153 memory_limit = memparse(p, &p) & PAGE_MASK; 154 pr_notice("Memory limited to %lldMB\n", memory_limit >> 20); 155 156 return 0; 157 } 158 early_param("mem", early_mem); 159 160 void __init arm64_memblock_init(void) 161 { 162 memblock_enforce_memory_limit(memory_limit); 163 164 /* 165 * Register the kernel text, kernel data, initrd, and initial 166 * pagetables with memblock. 167 */ 168 memblock_reserve(__pa(_text), _end - _text); 169 #ifdef CONFIG_BLK_DEV_INITRD 170 if (initrd_start) 171 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start); 172 #endif 173 174 early_init_fdt_scan_reserved_mem(); 175 176 /* 4GB maximum for 32-bit only capable devices */ 177 if (IS_ENABLED(CONFIG_ZONE_DMA)) 178 arm64_dma_phys_limit = max_zone_dma_phys(); 179 else 180 arm64_dma_phys_limit = PHYS_MASK + 1; 181 dma_contiguous_reserve(arm64_dma_phys_limit); 182 183 memblock_allow_resize(); 184 memblock_dump_all(); 185 } 186 187 void __init bootmem_init(void) 188 { 189 unsigned long min, max; 190 191 min = PFN_UP(memblock_start_of_DRAM()); 192 max = PFN_DOWN(memblock_end_of_DRAM()); 193 194 early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT); 195 196 /* 197 * Sparsemem tries to allocate bootmem in memory_present(), so must be 198 * done after the fixed reservations. 199 */ 200 arm64_memory_present(); 201 202 sparse_init(); 203 zone_sizes_init(min, max); 204 205 high_memory = __va((max << PAGE_SHIFT) - 1) + 1; 206 max_pfn = max_low_pfn = max; 207 } 208 209 #ifndef CONFIG_SPARSEMEM_VMEMMAP 210 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) 211 { 212 struct page *start_pg, *end_pg; 213 unsigned long pg, pgend; 214 215 /* 216 * Convert start_pfn/end_pfn to a struct page pointer. 217 */ 218 start_pg = pfn_to_page(start_pfn - 1) + 1; 219 end_pg = pfn_to_page(end_pfn - 1) + 1; 220 221 /* 222 * Convert to physical addresses, and round start upwards and end 223 * downwards. 224 */ 225 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 226 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 227 228 /* 229 * If there are free pages between these, free the section of the 230 * memmap array. 231 */ 232 if (pg < pgend) 233 free_bootmem(pg, pgend - pg); 234 } 235 236 /* 237 * The mem_map array can get very big. Free the unused area of the memory map. 238 */ 239 static void __init free_unused_memmap(void) 240 { 241 unsigned long start, prev_end = 0; 242 struct memblock_region *reg; 243 244 for_each_memblock(memory, reg) { 245 start = __phys_to_pfn(reg->base); 246 247 #ifdef CONFIG_SPARSEMEM 248 /* 249 * Take care not to free memmap entries that don't exist due 250 * to SPARSEMEM sections which aren't present. 251 */ 252 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); 253 #endif 254 /* 255 * If we had a previous bank, and there is a space between the 256 * current bank and the previous, free it. 257 */ 258 if (prev_end && prev_end < start) 259 free_memmap(prev_end, start); 260 261 /* 262 * Align up here since the VM subsystem insists that the 263 * memmap entries are valid from the bank end aligned to 264 * MAX_ORDER_NR_PAGES. 265 */ 266 prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size), 267 MAX_ORDER_NR_PAGES); 268 } 269 270 #ifdef CONFIG_SPARSEMEM 271 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) 272 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); 273 #endif 274 } 275 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ 276 277 /* 278 * mem_init() marks the free areas in the mem_map and tells us how much memory 279 * is free. This is done after various parts of the system have claimed their 280 * memory after the kernel image. 281 */ 282 void __init mem_init(void) 283 { 284 swiotlb_init(1); 285 286 set_max_mapnr(pfn_to_page(max_pfn) - mem_map); 287 288 #ifndef CONFIG_SPARSEMEM_VMEMMAP 289 free_unused_memmap(); 290 #endif 291 /* this will put all unused low memory onto the freelists */ 292 free_all_bootmem(); 293 294 mem_init_print_info(NULL); 295 296 #define MLK(b, t) b, t, ((t) - (b)) >> 10 297 #define MLM(b, t) b, t, ((t) - (b)) >> 20 298 #define MLG(b, t) b, t, ((t) - (b)) >> 30 299 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 300 301 pr_notice("Virtual kernel memory layout:\n" 302 #ifdef CONFIG_KASAN 303 " kasan : 0x%16lx - 0x%16lx (%6ld GB)\n" 304 #endif 305 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n" 306 #ifdef CONFIG_SPARSEMEM_VMEMMAP 307 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n" 308 " 0x%16lx - 0x%16lx (%6ld MB actual)\n" 309 #endif 310 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n" 311 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n" 312 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n" 313 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n" 314 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n" 315 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n" 316 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n", 317 #ifdef CONFIG_KASAN 318 MLG(KASAN_SHADOW_START, KASAN_SHADOW_END), 319 #endif 320 MLG(VMALLOC_START, VMALLOC_END), 321 #ifdef CONFIG_SPARSEMEM_VMEMMAP 322 MLG((unsigned long)vmemmap, 323 (unsigned long)vmemmap + VMEMMAP_SIZE), 324 MLM((unsigned long)virt_to_page(PAGE_OFFSET), 325 (unsigned long)virt_to_page(high_memory)), 326 #endif 327 MLK(FIXADDR_START, FIXADDR_TOP), 328 MLM(PCI_IO_START, PCI_IO_END), 329 MLM(MODULES_VADDR, MODULES_END), 330 MLM(PAGE_OFFSET, (unsigned long)high_memory), 331 MLK_ROUNDUP(__init_begin, __init_end), 332 MLK_ROUNDUP(_text, _etext), 333 MLK_ROUNDUP(_sdata, _edata)); 334 335 #undef MLK 336 #undef MLM 337 #undef MLK_ROUNDUP 338 339 /* 340 * Check boundaries twice: Some fundamental inconsistencies can be 341 * detected at build time already. 342 */ 343 #ifdef CONFIG_COMPAT 344 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); 345 #endif 346 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 347 BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 348 349 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { 350 extern int sysctl_overcommit_memory; 351 /* 352 * On a machine this small we won't get anywhere without 353 * overcommit, so turn it on by default. 354 */ 355 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 356 } 357 } 358 359 void free_initmem(void) 360 { 361 fixup_init(); 362 free_initmem_default(0); 363 } 364 365 #ifdef CONFIG_BLK_DEV_INITRD 366 367 static int keep_initrd __initdata; 368 369 void __init free_initrd_mem(unsigned long start, unsigned long end) 370 { 371 if (!keep_initrd) 372 free_reserved_area((void *)start, (void *)end, 0, "initrd"); 373 } 374 375 static int __init keepinitrd_setup(char *__unused) 376 { 377 keep_initrd = 1; 378 return 1; 379 } 380 381 __setup("keepinitrd", keepinitrd_setup); 382 #endif 383