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/sections.h>
  35 #include <asm/setup.h>
  36 #include <asm/sizes.h>
  37 #include <asm/tlb.h>
  38
  39 #include "mm.h"
  40
  41 phys_addr_t memstart_addr __read_mostly = 0;
  42
  43 #ifdef CONFIG_BLK_DEV_INITRD
  44 static int __init early_initrd(char *p)
  45 {
  46         unsigned long start, size;
  47         char *endp;
  48
  49         start = memparse(p, &endp);
  50         if (*endp == ',') {
  51                 size = memparse(endp + 1, NULL);
  52
  53                 initrd_start = (unsigned long)__va(start);
  54                 initrd_end = (unsigned long)__va(start + size);
  55         }
  56         return 0;
  57 }
  58 early_param("initrd", early_initrd);
  59 #endif
  60
  61 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
  62
  63 static void __init zone_sizes_init(unsigned long min, unsigned long max)
  64 {
  65         struct memblock_region *reg;
  66         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  67         unsigned long max_dma32 = min;
  68
  69         memset(zone_size, 0, sizeof(zone_size));
  70
  71 #ifdef CONFIG_ZONE_DMA32
  72         /* 4GB maximum for 32-bit only capable devices */
  73         max_dma32 = max(min, min(max, MAX_DMA32_PFN));
  74         zone_size[ZONE_DMA32] = max_dma32 - min;
  75 #endif
  76         zone_size[ZONE_NORMAL] = max - max_dma32;
  77
  78         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  79
  80         for_each_memblock(memory, reg) {
  81                 unsigned long start = memblock_region_memory_base_pfn(reg);
  82                 unsigned long end = memblock_region_memory_end_pfn(reg);
  83
  84                 if (start >= max)
  85                         continue;
  86 #ifdef CONFIG_ZONE_DMA32
  87                 if (start < max_dma32) {
  88                         unsigned long dma_end = min(end, max_dma32);
  89                         zhole_size[ZONE_DMA32] -= dma_end - start;
  90                 }
  91 #endif
  92                 if (end > max_dma32) {
  93                         unsigned long normal_end = min(end, max);
  94                         unsigned long normal_start = max(start, max_dma32);
  95                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
  96                 }
  97         }
  98
  99         free_area_init_node(0, zone_size, min, zhole_size);
 100 }
 101
 102 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 103 int pfn_valid(unsigned long pfn)
 104 {
 105         return memblock_is_memory(pfn << PAGE_SHIFT);
 106 }
 107 EXPORT_SYMBOL(pfn_valid);
 108 #endif
 109
 110 #ifndef CONFIG_SPARSEMEM
 111 static void arm64_memory_present(void)
 112 {
 113 }
 114 #else
 115 static void arm64_memory_present(void)
 116 {
 117         struct memblock_region *reg;
 118
 119         for_each_memblock(memory, reg)
 120                 memory_present(0, memblock_region_memory_base_pfn(reg),
 121                                memblock_region_memory_end_pfn(reg));
 122 }
 123 #endif
 124
 125 void __init arm64_memblock_init(void)
 126 {
 127         u64 *reserve_map, base, size;
 128
 129         /* Register the kernel text, kernel data and initrd with memblock */
 130         memblock_reserve(__pa(_text), _end - _text);
 131 #ifdef CONFIG_BLK_DEV_INITRD
 132         if (initrd_start)
 133                 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
 134 #endif
 135
 136         /*
 137          * Reserve the page tables.  These are already in use,
 138          * and can only be in node 0.
 139          */
 140         memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
 141         memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
 142
 143         /* Reserve the dtb region */
 144         memblock_reserve(virt_to_phys(initial_boot_params),
 145                          be32_to_cpu(initial_boot_params->totalsize));
 146
 147         /*
 148          * Process the reserve map.  This will probably overlap the initrd
 149          * and dtb locations which are already reserved, but overlapping
 150          * doesn't hurt anything
 151          */
 152         reserve_map = ((void*)initial_boot_params) +
 153                         be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 154         while (1) {
 155                 base = be64_to_cpup(reserve_map++);
 156                 size = be64_to_cpup(reserve_map++);
 157                 if (!size)
 158                         break;
 159                 memblock_reserve(base, size);
 160         }
 161
 162         memblock_allow_resize();
 163         memblock_dump_all();
 164 }
 165
 166 void __init bootmem_init(void)
 167 {
 168         unsigned long min, max;
 169
 170         min = PFN_UP(memblock_start_of_DRAM());
 171         max = PFN_DOWN(memblock_end_of_DRAM());
 172
 173         /*
 174          * Sparsemem tries to allocate bootmem in memory_present(), so must be
 175          * done after the fixed reservations.
 176          */
 177         arm64_memory_present();
 178
 179         sparse_init();
 180         zone_sizes_init(min, max);
 181
 182         high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
 183         max_pfn = max_low_pfn = max;
 184 }
 185
 186 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 187 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 188 {
 189         struct page *start_pg, *end_pg;
 190         unsigned long pg, pgend;
 191
 192         /*
 193          * Convert start_pfn/end_pfn to a struct page pointer.
 194          */
 195         start_pg = pfn_to_page(start_pfn - 1) + 1;
 196         end_pg = pfn_to_page(end_pfn - 1) + 1;
 197
 198         /*
 199          * Convert to physical addresses, and round start upwards and end
 200          * downwards.
 201          */
 202         pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
 203         pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
 204
 205         /*
 206          * If there are free pages between these, free the section of the
 207          * memmap array.
 208          */
 209         if (pg < pgend)
 210                 free_bootmem(pg, pgend - pg);
 211 }
 212
 213 /*
 214  * The mem_map array can get very big. Free the unused area of the memory map.
 215  */
 216 static void __init free_unused_memmap(void)
 217 {
 218         unsigned long start, prev_end = 0;
 219         struct memblock_region *reg;
 220
 221         for_each_memblock(memory, reg) {
 222                 start = __phys_to_pfn(reg->base);
 223
 224 #ifdef CONFIG_SPARSEMEM
 225                 /*
 226                  * Take care not to free memmap entries that don't exist due
 227                  * to SPARSEMEM sections which aren't present.
 228                  */
 229                 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
 230 #endif
 231                 /*
 232                  * If we had a previous bank, and there is a space between the
 233                  * current bank and the previous, free it.
 234                  */
 235                 if (prev_end && prev_end < start)
 236                         free_memmap(prev_end, start);
 237
 238                 /*
 239                  * Align up here since the VM subsystem insists that the
 240                  * memmap entries are valid from the bank end aligned to
 241                  * MAX_ORDER_NR_PAGES.
 242                  */
 243                 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
 244                                  MAX_ORDER_NR_PAGES);
 245         }
 246
 247 #ifdef CONFIG_SPARSEMEM
 248         if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
 249                 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
 250 #endif
 251 }
 252 #endif  /* !CONFIG_SPARSEMEM_VMEMMAP */
 253
 254 /*
 255  * mem_init() marks the free areas in the mem_map and tells us how much memory
 256  * is free.  This is done after various parts of the system have claimed their
 257  * memory after the kernel image.
 258  */
 259 void __init mem_init(void)
 260 {
 261         arm64_swiotlb_init();
 262
 263         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 264
 265 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 266         free_unused_memmap();
 267 #endif
 268         /* this will put all unused low memory onto the freelists */
 269         free_all_bootmem();
 270
 271         mem_init_print_info(NULL);
 272
 273 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 274 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 275 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 276
 277         pr_notice("Virtual kernel memory layout:\n"
 278                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 279 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 280                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 281 #endif
 282                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 283                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 284                   "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 285                   "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 286                   "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
 287                   MLM(VMALLOC_START, VMALLOC_END),
 288 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 289                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 290                       (unsigned long)virt_to_page(high_memory)),
 291 #endif
 292                   MLM(MODULES_VADDR, MODULES_END),
 293                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 294
 295                   MLK_ROUNDUP(__init_begin, __init_end),
 296                   MLK_ROUNDUP(_text, _etext),
 297                   MLK_ROUNDUP(_sdata, _edata));
 298
 299 #undef MLK
 300 #undef MLM
 301 #undef MLK_ROUNDUP
 302
 303         /*
 304          * Check boundaries twice: Some fundamental inconsistencies can be
 305          * detected at build time already.
 306          */
 307 #ifdef CONFIG_COMPAT
 308         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 309 #endif
 310         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 311         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 312
 313         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 314                 extern int sysctl_overcommit_memory;
 315                 /*
 316                  * On a machine this small we won't get anywhere without
 317                  * overcommit, so turn it on by default.
 318                  */
 319                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 320         }
 321 }
 322
 323 void free_initmem(void)
 324 {
 325         free_initmem_default(0);
 326 }
 327
 328 #ifdef CONFIG_BLK_DEV_INITRD
 329
 330 static int keep_initrd;
 331
 332 void free_initrd_mem(unsigned long start, unsigned long end)
 333 {
 334         if (!keep_initrd)
 335                 free_reserved_area((void *)start, (void *)end, 0, "initrd");
 336 }
 337
 338 static int __init keepinitrd_setup(char *__unused)
 339 {
 340         keep_initrd = 1;
 341         return 1;
 342 }
 343
 344 __setup("keepinitrd", keepinitrd_setup);
 345 #endif