arch/arm64/mm/init.c

   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/prom.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 static unsigned long phys_initrd_start __initdata = 0;
  45 static unsigned long phys_initrd_size __initdata = 0;
  46
  47 phys_addr_t memstart_addr __read_mostly = 0;
  48
  49 void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
  50 {
  51         phys_initrd_start = start;
  52         phys_initrd_size = end - start;
  53 }
  54
  55 static int __init early_initrd(char *p)
  56 {
  57         unsigned long start, size;
  58         char *endp;
  59
  60         start = memparse(p, &endp);
  61         if (*endp == ',') {
  62                 size = memparse(endp + 1, NULL);
  63
  64                 phys_initrd_start = start;
  65                 phys_initrd_size = size;
  66         }
  67         return 0;
  68 }
  69 early_param("initrd", early_initrd);
  70
  71 static void __init zone_sizes_init(unsigned long min, unsigned long max)
  72 {
  73         struct memblock_region *reg;
  74         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  75         unsigned long max_dma = min;
  76
  77         memset(zone_size, 0, sizeof(zone_size));
  78
  79         /* 4GB maximum for 32-bit only capable devices */
  80         if (IS_ENABLED(CONFIG_ZONE_DMA)) {
  81                 unsigned long max_dma_phys =
  82                         (unsigned long)dma_to_phys(NULL, DMA_BIT_MASK(32) + 1);
  83                 max_dma = max(min, min(max, max_dma_phys >> PAGE_SHIFT));
  84                 zone_size[ZONE_DMA] = max_dma - min;
  85         }
  86         zone_size[ZONE_NORMAL] = max - max_dma;
  87
  88         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  89
  90         for_each_memblock(memory, reg) {
  91                 unsigned long start = memblock_region_memory_base_pfn(reg);
  92                 unsigned long end = memblock_region_memory_end_pfn(reg);
  93
  94                 if (start >= max)
  95                         continue;
  96
  97                 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
  98                         unsigned long dma_end = min(end, max_dma);
  99                         zhole_size[ZONE_DMA] -= dma_end - start;
 100                 }
 101
 102                 if (end > max_dma) {
 103                         unsigned long normal_end = min(end, max);
 104                         unsigned long normal_start = max(start, max_dma);
 105                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
 106                 }
 107         }
 108
 109         free_area_init_node(0, zone_size, min, zhole_size);
 110 }
 111
 112 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 113 int pfn_valid(unsigned long pfn)
 114 {
 115         return memblock_is_memory(pfn << PAGE_SHIFT);
 116 }
 117 EXPORT_SYMBOL(pfn_valid);
 118 #endif
 119
 120 #ifndef CONFIG_SPARSEMEM
 121 static void arm64_memory_present(void)
 122 {
 123 }
 124 #else
 125 static void arm64_memory_present(void)
 126 {
 127         struct memblock_region *reg;
 128
 129         for_each_memblock(memory, reg)
 130                 memory_present(0, memblock_region_memory_base_pfn(reg),
 131                                memblock_region_memory_end_pfn(reg));
 132 }
 133 #endif
 134
 135 void __init arm64_memblock_init(void)
 136 {
 137         u64 *reserve_map, base, size;
 138
 139         /*
 140          * Register the kernel text, kernel data, initrd, and initial
 141          * pagetables with memblock.
 142          */
 143         memblock_reserve(__pa(_text), _end - _text);
 144 #ifdef CONFIG_BLK_DEV_INITRD
 145         if (phys_initrd_size) {
 146                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 147
 148                 /* Now convert initrd to virtual addresses */
 149                 initrd_start = __phys_to_virt(phys_initrd_start);
 150                 initrd_end = initrd_start + phys_initrd_size;
 151         }
 152 #endif
 153
 154         /* Reserve the dtb region */
 155         memblock_reserve(virt_to_phys(initial_boot_params),
 156                          be32_to_cpu(initial_boot_params->totalsize));
 157
 158         /*
 159          * Process the reserve map.  This will probably overlap the initrd
 160          * and dtb locations which are already reserved, but overlapping
 161          * doesn't hurt anything
 162          */
 163         reserve_map = ((void*)initial_boot_params) +
 164                         be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 165         while (1) {
 166                 base = be64_to_cpup(reserve_map++);
 167                 size = be64_to_cpup(reserve_map++);
 168                 if (!size)
 169                         break;
 170                 memblock_reserve(base, size);
 171         }
 172
 173         early_init_fdt_scan_reserved_mem();
 174         dma_contiguous_reserve(0);
 175
 176         memblock_allow_resize();
 177         memblock_dump_all();
 178 }
 179
 180 void __init bootmem_init(void)
 181 {
 182         unsigned long min, max;
 183
 184         min = PFN_UP(memblock_start_of_DRAM());
 185         max = PFN_DOWN(memblock_end_of_DRAM());
 186
 187         /*
 188          * Sparsemem tries to allocate bootmem in memory_present(), so must be
 189          * done after the fixed reservations.
 190          */
 191         arm64_memory_present();
 192
 193         sparse_init();
 194         zone_sizes_init(min, max);
 195
 196         high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
 197         max_pfn = max_low_pfn = max;
 198 }
 199
 200 /*
 201  * Poison init memory with an undefined instruction (0x0).
 202  */
 203 static inline void poison_init_mem(void *s, size_t count)
 204 {
 205         memset(s, 0, count);
 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(start + __phys_to_pfn(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         unsigned long reserved_pages, free_pages;
 284         struct memblock_region *reg;
 285
 286         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 287
 288 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 289         /* this will put all unused low memory onto the freelists */
 290         free_unused_memmap();
 291 #endif
 292
 293         totalram_pages += free_all_bootmem();
 294
 295         reserved_pages = free_pages = 0;
 296
 297         for_each_memblock(memory, reg) {
 298                 unsigned int pfn1, pfn2;
 299                 struct page *page, *end;
 300
 301                 pfn1 = __phys_to_pfn(reg->base);
 302                 pfn2 = pfn1 + __phys_to_pfn(reg->size);
 303
 304                 page = pfn_to_page(pfn1);
 305                 end  = pfn_to_page(pfn2 - 1) + 1;
 306
 307                 do {
 308                         if (PageReserved(page))
 309                                 reserved_pages++;
 310                         else if (!page_count(page))
 311                                 free_pages++;
 312                         page++;
 313                 } while (page < end);
 314         }
 315
 316         /*
 317          * Since our memory may not be contiguous, calculate the real number
 318          * of pages we have in this system.
 319          */
 320         pr_info("Memory:");
 321         num_physpages = 0;
 322         for_each_memblock(memory, reg) {
 323                 unsigned long pages = memblock_region_memory_end_pfn(reg) -
 324                         memblock_region_memory_base_pfn(reg);
 325                 num_physpages += pages;
 326                 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
 327         }
 328         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 329
 330         pr_notice("Memory: %luk/%luk available, %luk reserved\n",
 331                   nr_free_pages() << (PAGE_SHIFT-10),
 332                   free_pages << (PAGE_SHIFT-10),
 333                   reserved_pages << (PAGE_SHIFT-10));
 334
 335 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 336 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 337 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 338
 339         pr_notice("Virtual kernel memory layout:\n"
 340                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 341 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 342                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 343 #endif
 344                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 345                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 346                   "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 347                   "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 348                   "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
 349                   MLM(VMALLOC_START, VMALLOC_END),
 350 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 351                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 352                       (unsigned long)virt_to_page(high_memory)),
 353 #endif
 354                   MLM(MODULES_VADDR, MODULES_END),
 355                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 356
 357                   MLK_ROUNDUP(__init_begin, __init_end),
 358                   MLK_ROUNDUP(_text, _etext),
 359                   MLK_ROUNDUP(_sdata, _edata));
 360
 361 #undef MLK
 362 #undef MLM
 363 #undef MLK_ROUNDUP
 364
 365         /*
 366          * Check boundaries twice: Some fundamental inconsistencies can be
 367          * detected at build time already.
 368          */
 369 #ifdef CONFIG_COMPAT
 370         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 371 #endif
 372         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 373         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 374
 375         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 376                 extern int sysctl_overcommit_memory;
 377                 /*
 378                  * On a machine this small we won't get anywhere without
 379                  * overcommit, so turn it on by default.
 380                  */
 381                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 382         }
 383 }
 384
 385 void free_initmem(void)
 386 {
 387         poison_init_mem(__init_begin, __init_end - __init_begin);
 388         free_initmem_default(0);
 389 }
 390
 391 #ifdef CONFIG_BLK_DEV_INITRD
 392
 393 static int keep_initrd;
 394
 395 void free_initrd_mem(unsigned long start, unsigned long end)
 396 {
 397         if (!keep_initrd) {
 398                 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
 399                 free_reserved_area(start, end, 0, "initrd");
 400         }
 401 }
 402
 403 static int __init keepinitrd_setup(char *__unused)
 404 {
 405         keep_initrd = 1;
 406         return 1;
 407 }
 408
 409 __setup("keepinitrd", keepinitrd_setup);
 410 #endif