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
  34 #include <asm/prom.h>
  35 #include <asm/sections.h>
  36 #include <asm/setup.h>
  37 #include <asm/sizes.h>
  38 #include <asm/tlb.h>
  39
  40 #include "mm.h"
  41
  42 static unsigned long phys_initrd_start __initdata = 0;
  43 static unsigned long phys_initrd_size __initdata = 0;
  44
  45 phys_addr_t memstart_addr __read_mostly = 0;
  46
  47 void __init early_init_dt_setup_initrd_arch(unsigned long start,
  48                                             unsigned long end)
  49 {
  50         phys_initrd_start = start;
  51         phys_initrd_size = end - start;
  52 }
  53
  54 static int __init early_initrd(char *p)
  55 {
  56         unsigned long start, size;
  57         char *endp;
  58
  59         start = memparse(p, &endp);
  60         if (*endp == ',') {
  61                 size = memparse(endp + 1, NULL);
  62
  63                 phys_initrd_start = start;
  64                 phys_initrd_size = size;
  65         }
  66         return 0;
  67 }
  68 early_param("initrd", early_initrd);
  69
  70 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
  71
  72 static void __init zone_sizes_init(unsigned long min, unsigned long max)
  73 {
  74         struct memblock_region *reg;
  75         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  76         unsigned long max_dma32 = min;
  77
  78         memset(zone_size, 0, sizeof(zone_size));
  79
  80 #ifdef CONFIG_ZONE_DMA32
  81         /* 4GB maximum for 32-bit only capable devices */
  82         max_dma32 = max(min, min(max, MAX_DMA32_PFN));
  83         zone_size[ZONE_DMA32] = max_dma32 - min;
  84 #endif
  85         zone_size[ZONE_NORMAL] = max - max_dma32;
  86
  87         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  88
  89         for_each_memblock(memory, reg) {
  90                 unsigned long start = memblock_region_memory_base_pfn(reg);
  91                 unsigned long end = memblock_region_memory_end_pfn(reg);
  92
  93                 if (start >= max)
  94                         continue;
  95 #ifdef CONFIG_ZONE_DMA32
  96                 if (start < max_dma32) {
  97                         unsigned long dma_end = min(end, max_dma32);
  98                         zhole_size[ZONE_DMA32] -= dma_end - start;
  99                 }
 100 #endif
 101                 if (end > max_dma32) {
 102                         unsigned long normal_end = min(end, max);
 103                         unsigned long normal_start = max(start, max_dma32);
 104                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
 105                 }
 106         }
 107
 108         free_area_init_node(0, zone_size, min, zhole_size);
 109 }
 110
 111 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 112 int pfn_valid(unsigned long pfn)
 113 {
 114         return memblock_is_memory(pfn << PAGE_SHIFT);
 115 }
 116 EXPORT_SYMBOL(pfn_valid);
 117 #endif
 118
 119 #ifndef CONFIG_SPARSEMEM
 120 static void arm64_memory_present(void)
 121 {
 122 }
 123 #else
 124 static void arm64_memory_present(void)
 125 {
 126         struct memblock_region *reg;
 127
 128         for_each_memblock(memory, reg)
 129                 memory_present(0, memblock_region_memory_base_pfn(reg),
 130                                memblock_region_memory_end_pfn(reg));
 131 }
 132 #endif
 133
 134 void __init arm64_memblock_init(void)
 135 {
 136         u64 *reserve_map, base, size;
 137
 138         /* Register the kernel text, kernel data and initrd with memblock */
 139         memblock_reserve(__pa(_text), _end - _text);
 140 #ifdef CONFIG_BLK_DEV_INITRD
 141         if (phys_initrd_size) {
 142                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 143
 144                 /* Now convert initrd to virtual addresses */
 145                 initrd_start = __phys_to_virt(phys_initrd_start);
 146                 initrd_end = initrd_start + phys_initrd_size;
 147         }
 148 #endif
 149
 150         /*
 151          * Reserve the page tables.  These are already in use,
 152          * and can only be in node 0.
 153          */
 154         memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
 155         memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
 156
 157         /* Reserve the dtb region */
 158         memblock_reserve(virt_to_phys(initial_boot_params),
 159                          be32_to_cpu(initial_boot_params->totalsize));
 160
 161         /*
 162          * Process the reserve map.  This will probably overlap the initrd
 163          * and dtb locations which are already reserved, but overlapping
 164          * doesn't hurt anything
 165          */
 166         reserve_map = ((void*)initial_boot_params) +
 167                         be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 168         while (1) {
 169                 base = be64_to_cpup(reserve_map++);
 170                 size = be64_to_cpup(reserve_map++);
 171                 if (!size)
 172                         break;
 173                 memblock_reserve(base, size);
 174         }
 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         arm64_swiotlb_init();
 287
 288         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 289
 290 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 291         /* this will put all unused low memory onto the freelists */
 292         free_unused_memmap();
 293 #endif
 294
 295         totalram_pages += free_all_bootmem();
 296
 297         reserved_pages = free_pages = 0;
 298
 299         for_each_memblock(memory, reg) {
 300                 unsigned int pfn1, pfn2;
 301                 struct page *page, *end;
 302
 303                 pfn1 = __phys_to_pfn(reg->base);
 304                 pfn2 = pfn1 + __phys_to_pfn(reg->size);
 305
 306                 page = pfn_to_page(pfn1);
 307                 end  = pfn_to_page(pfn2 - 1) + 1;
 308
 309                 do {
 310                         if (PageReserved(page))
 311                                 reserved_pages++;
 312                         else if (!page_count(page))
 313                                 free_pages++;
 314                         page++;
 315                 } while (page < end);
 316         }
 317
 318         /*
 319          * Since our memory may not be contiguous, calculate the real number
 320          * of pages we have in this system.
 321          */
 322         pr_info("Memory:");
 323         num_physpages = 0;
 324         for_each_memblock(memory, reg) {
 325                 unsigned long pages = memblock_region_memory_end_pfn(reg) -
 326                         memblock_region_memory_base_pfn(reg);
 327                 num_physpages += pages;
 328                 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
 329         }
 330         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 331
 332         pr_notice("Memory: %luk/%luk available, %luk reserved\n",
 333                   nr_free_pages() << (PAGE_SHIFT-10),
 334                   free_pages << (PAGE_SHIFT-10),
 335                   reserved_pages << (PAGE_SHIFT-10));
 336
 337 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 338 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 339 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 340
 341         pr_notice("Virtual kernel memory layout:\n"
 342                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 343 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 344                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 345 #endif
 346                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 347                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 348                   "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 349                   "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 350                   "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
 351                   MLM(VMALLOC_START, VMALLOC_END),
 352 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 353                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 354                       (unsigned long)virt_to_page(high_memory)),
 355 #endif
 356                   MLM(MODULES_VADDR, MODULES_END),
 357                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 358
 359                   MLK_ROUNDUP(__init_begin, __init_end),
 360                   MLK_ROUNDUP(_text, _etext),
 361                   MLK_ROUNDUP(_sdata, _edata));
 362
 363 #undef MLK
 364 #undef MLM
 365 #undef MLK_ROUNDUP
 366
 367         /*
 368          * Check boundaries twice: Some fundamental inconsistencies can be
 369          * detected at build time already.
 370          */
 371 #ifdef CONFIG_COMPAT
 372         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 373 #endif
 374         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 375         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 376
 377         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 378                 extern int sysctl_overcommit_memory;
 379                 /*
 380                  * On a machine this small we won't get anywhere without
 381                  * overcommit, so turn it on by default.
 382                  */
 383                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 384         }
 385 }
 386
 387 void free_initmem(void)
 388 {
 389         poison_init_mem(__init_begin, __init_end - __init_begin);
 390         free_initmem_default(0);
 391 }
 392
 393 #ifdef CONFIG_BLK_DEV_INITRD
 394
 395 static int keep_initrd;
 396
 397 void free_initrd_mem(unsigned long start, unsigned long end)
 398 {
 399         if (!keep_initrd) {
 400                 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
 401                 free_reserved_area(start, end, 0, "initrd");
 402         }
 403 }
 404
 405 static int __init keepinitrd_setup(char *__unused)
 406 {
 407         keep_initrd = 1;
 408         return 1;
 409 }
 410
 411 __setup("keepinitrd", keepinitrd_setup);
 412 #endif