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 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 if (IS_ENABLED(CONFIG_ZONE_DMA)) { 90 max_dma = PFN_DOWN(arm64_dma_phys_limit); 91 zone_size[ZONE_DMA] = max_dma - min; 92 } 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 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) { 105 unsigned long dma_end = min(end, max_dma); 106 zhole_size[ZONE_DMA] -= dma_end - start; 107 } 108 109 if (end > max_dma) { 110 unsigned long normal_end = min(end, max); 111 unsigned long normal_start = max(start, max_dma); 112 zhole_size[ZONE_NORMAL] -= normal_end - normal_start; 113 } 114 } 115 116 free_area_init_node(0, zone_size, min, zhole_size); 117 } 118 119 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 120 int pfn_valid(unsigned long pfn) 121 { 122 return memblock_is_memory(pfn << PAGE_SHIFT); 123 } 124 EXPORT_SYMBOL(pfn_valid); 125 #endif 126 127 #ifndef CONFIG_SPARSEMEM 128 static void arm64_memory_present(void) 129 { 130 } 131 #else 132 static void arm64_memory_present(void) 133 { 134 struct memblock_region *reg; 135 136 for_each_memblock(memory, reg) 137 memory_present(0, memblock_region_memory_base_pfn(reg), 138 memblock_region_memory_end_pfn(reg)); 139 } 140 #endif 141 142 static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX; 143 144 /* 145 * Limit the memory size that was specified via FDT. 146 */ 147 static int __init early_mem(char *p) 148 { 149 if (!p) 150 return 1; 151 152 memory_limit = memparse(p, &p) & PAGE_MASK; 153 pr_notice("Memory limited to %lldMB\n", memory_limit >> 20); 154 155 return 0; 156 } 157 early_param("mem", early_mem); 158 159 void __init arm64_memblock_init(void) 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 arm64_dma_phys_limit = max_zone_dma_phys(); 178 else 179 arm64_dma_phys_limit = PHYS_MASK + 1; 180 dma_contiguous_reserve(arm64_dma_phys_limit); 181 182 memblock_allow_resize(); 183 memblock_dump_all(); 184 } 185 186 void __init bootmem_init(void) 187 { 188 unsigned long min, max; 189 190 min = PFN_UP(memblock_start_of_DRAM()); 191 max = PFN_DOWN(memblock_end_of_DRAM()); 192 193 early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT); 194 195 /* 196 * Sparsemem tries to allocate bootmem in memory_present(), so must be 197 * done after the fixed reservations. 198 */ 199 arm64_memory_present(); 200 201 sparse_init(); 202 zone_sizes_init(min, max); 203 204 high_memory = __va((max << PAGE_SHIFT) - 1) + 1; 205 max_pfn = max_low_pfn = max; 206 } 207 208 #ifndef CONFIG_SPARSEMEM_VMEMMAP 209 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn) 210 { 211 struct page *start_pg, *end_pg; 212 unsigned long pg, pgend; 213 214 /* 215 * Convert start_pfn/end_pfn to a struct page pointer. 216 */ 217 start_pg = pfn_to_page(start_pfn - 1) + 1; 218 end_pg = pfn_to_page(end_pfn - 1) + 1; 219 220 /* 221 * Convert to physical addresses, and round start upwards and end 222 * downwards. 223 */ 224 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 225 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 226 227 /* 228 * If there are free pages between these, free the section of the 229 * memmap array. 230 */ 231 if (pg < pgend) 232 free_bootmem(pg, pgend - pg); 233 } 234 235 /* 236 * The mem_map array can get very big. Free the unused area of the memory map. 237 */ 238 static void __init free_unused_memmap(void) 239 { 240 unsigned long start, prev_end = 0; 241 struct memblock_region *reg; 242 243 for_each_memblock(memory, reg) { 244 start = __phys_to_pfn(reg->base); 245 246 #ifdef CONFIG_SPARSEMEM 247 /* 248 * Take care not to free memmap entries that don't exist due 249 * to SPARSEMEM sections which aren't present. 250 */ 251 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION)); 252 #endif 253 /* 254 * If we had a previous bank, and there is a space between the 255 * current bank and the previous, free it. 256 */ 257 if (prev_end && prev_end < start) 258 free_memmap(prev_end, start); 259 260 /* 261 * Align up here since the VM subsystem insists that the 262 * memmap entries are valid from the bank end aligned to 263 * MAX_ORDER_NR_PAGES. 264 */ 265 prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size), 266 MAX_ORDER_NR_PAGES); 267 } 268 269 #ifdef CONFIG_SPARSEMEM 270 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) 271 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION)); 272 #endif 273 } 274 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ 275 276 /* 277 * mem_init() marks the free areas in the mem_map and tells us how much memory 278 * is free. This is done after various parts of the system have claimed their 279 * memory after the kernel image. 280 */ 281 void __init mem_init(void) 282 { 283 swiotlb_init(1); 284 285 set_max_mapnr(pfn_to_page(max_pfn) - mem_map); 286 287 #ifndef CONFIG_SPARSEMEM_VMEMMAP 288 free_unused_memmap(); 289 #endif 290 /* this will put all unused low memory onto the freelists */ 291 free_all_bootmem(); 292 293 mem_init_print_info(NULL); 294 295 #define MLK(b, t) b, t, ((t) - (b)) >> 10 296 #define MLM(b, t) b, t, ((t) - (b)) >> 20 297 #define MLG(b, t) b, t, ((t) - (b)) >> 30 298 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 299 300 pr_notice("Virtual kernel memory layout:\n" 301 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n" 302 #ifdef CONFIG_SPARSEMEM_VMEMMAP 303 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n" 304 " 0x%16lx - 0x%16lx (%6ld MB actual)\n" 305 #endif 306 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n" 307 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n" 308 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n" 309 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n" 310 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n" 311 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n" 312 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n", 313 MLG(VMALLOC_START, VMALLOC_END), 314 #ifdef CONFIG_SPARSEMEM_VMEMMAP 315 MLG((unsigned long)vmemmap, 316 (unsigned long)vmemmap + VMEMMAP_SIZE), 317 MLM((unsigned long)virt_to_page(PAGE_OFFSET), 318 (unsigned long)virt_to_page(high_memory)), 319 #endif 320 MLK(FIXADDR_START, FIXADDR_TOP), 321 MLM(PCI_IO_START, PCI_IO_END), 322 MLM(MODULES_VADDR, MODULES_END), 323 MLM(PAGE_OFFSET, (unsigned long)high_memory), 324 MLK_ROUNDUP(__init_begin, __init_end), 325 MLK_ROUNDUP(_text, _etext), 326 MLK_ROUNDUP(_sdata, _edata)); 327 328 #undef MLK 329 #undef MLM 330 #undef MLK_ROUNDUP 331 332 /* 333 * Check boundaries twice: Some fundamental inconsistencies can be 334 * detected at build time already. 335 */ 336 #ifdef CONFIG_COMPAT 337 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); 338 #endif 339 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 340 BUG_ON(TASK_SIZE_64 > MODULES_VADDR); 341 342 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { 343 extern int sysctl_overcommit_memory; 344 /* 345 * On a machine this small we won't get anywhere without 346 * overcommit, so turn it on by default. 347 */ 348 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 349 } 350 } 351 352 void free_initmem(void) 353 { 354 fixup_init(); 355 free_initmem_default(0); 356 free_alternatives_memory(); 357 } 358 359 #ifdef CONFIG_BLK_DEV_INITRD 360 361 static int keep_initrd __initdata; 362 363 void __init free_initrd_mem(unsigned long start, unsigned long end) 364 { 365 if (!keep_initrd) 366 free_reserved_area((void *)start, (void *)end, 0, "initrd"); 367 } 368 369 static int __init keepinitrd_setup(char *__unused) 370 { 371 keep_initrd = 1; 372 return 1; 373 } 374 375 __setup("keepinitrd", keepinitrd_setup); 376 #endif 377