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-contiguous.h>
  34
  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 phys_addr_t memstart_addr __read_mostly = 0;
  43
  44 #ifdef CONFIG_BLK_DEV_INITRD
  45 static int __init early_initrd(char *p)
  46 {
  47         unsigned long start, size;
  48         char *endp;
  49
  50         start = memparse(p, &endp);
  51         if (*endp == ',') {
  52                 size = memparse(endp + 1, NULL);
  53
  54                 initrd_start = (unsigned long)__va(start);
  55                 initrd_end = (unsigned long)__va(start + size);
  56         }
  57         return 0;
  58 }
  59 early_param("initrd", early_initrd);
  60 #endif
  61
  62 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
  63
  64 static void __init zone_sizes_init(unsigned long min, unsigned long max)
  65 {
  66         struct memblock_region *reg;
  67         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  68         unsigned long max_dma32 = min;
  69
  70         memset(zone_size, 0, sizeof(zone_size));
  71
  72 #ifdef CONFIG_ZONE_DMA32
  73         /* 4GB maximum for 32-bit only capable devices */
  74         max_dma32 = max(min, min(max, MAX_DMA32_PFN));
  75         zone_size[ZONE_DMA32] = max_dma32 - min;
  76 #endif
  77         zone_size[ZONE_NORMAL] = max - max_dma32;
  78
  79         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  80
  81         for_each_memblock(memory, reg) {
  82                 unsigned long start = memblock_region_memory_base_pfn(reg);
  83                 unsigned long end = memblock_region_memory_end_pfn(reg);
  84
  85                 if (start >= max)
  86                         continue;
  87 #ifdef CONFIG_ZONE_DMA32
  88                 if (start < max_dma32) {
  89                         unsigned long dma_end = min(end, max_dma32);
  90                         zhole_size[ZONE_DMA32] -= dma_end - start;
  91                 }
  92 #endif
  93                 if (end > max_dma32) {
  94                         unsigned long normal_end = min(end, max);
  95                         unsigned long normal_start = max(start, max_dma32);
  96                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
  97                 }
  98         }
  99
 100         free_area_init_node(0, zone_size, min, zhole_size);
 101 }
 102
 103 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 104 int pfn_valid(unsigned long pfn)
 105 {
 106         return memblock_is_memory(pfn << PAGE_SHIFT);
 107 }
 108 EXPORT_SYMBOL(pfn_valid);
 109 #endif
 110
 111 #ifndef CONFIG_SPARSEMEM
 112 static void arm64_memory_present(void)
 113 {
 114 }
 115 #else
 116 static void arm64_memory_present(void)
 117 {
 118         struct memblock_region *reg;
 119
 120         for_each_memblock(memory, reg)
 121                 memory_present(0, memblock_region_memory_base_pfn(reg),
 122                                memblock_region_memory_end_pfn(reg));
 123 }
 124 #endif
 125
 126 void __init arm64_memblock_init(void)
 127 {
 128         u64 *reserve_map, base, size;
 129
 130         /* Register the kernel text, kernel data and initrd with memblock */
 131         memblock_reserve(__pa(_text), _end - _text);
 132 #ifdef CONFIG_BLK_DEV_INITRD
 133         if (initrd_start)
 134                 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
 135 #endif
 136
 137         /*
 138          * Reserve the page tables.  These are already in use,
 139          * and can only be in node 0.
 140          */
 141         memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
 142         memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
 143
 144         /* Reserve the dtb region */
 145         memblock_reserve(virt_to_phys(initial_boot_params),
 146                          be32_to_cpu(initial_boot_params->totalsize));
 147
 148         /*
 149          * Process the reserve map.  This will probably overlap the initrd
 150          * and dtb locations which are already reserved, but overlapping
 151          * doesn't hurt anything
 152          */
 153         reserve_map = ((void*)initial_boot_params) +
 154                         be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 155         while (1) {
 156                 base = be64_to_cpup(reserve_map++);
 157                 size = be64_to_cpup(reserve_map++);
 158                 if (!size)
 159                         break;
 160                 memblock_reserve(base, size);
 161         }
 162
 163         dma_contiguous_reserve(0);
 164
 165         memblock_allow_resize();
 166         memblock_dump_all();
 167 }
 168
 169 void __init bootmem_init(void)
 170 {
 171         unsigned long min, max;
 172
 173         min = PFN_UP(memblock_start_of_DRAM());
 174         max = PFN_DOWN(memblock_end_of_DRAM());
 175
 176         /*
 177          * Sparsemem tries to allocate bootmem in memory_present(), so must be
 178          * done after the fixed reservations.
 179          */
 180         arm64_memory_present();
 181
 182         sparse_init();
 183         zone_sizes_init(min, max);
 184
 185         high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
 186         max_pfn = max_low_pfn = max;
 187 }
 188
 189 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 190 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 191 {
 192         struct page *start_pg, *end_pg;
 193         unsigned long pg, pgend;
 194
 195         /*
 196          * Convert start_pfn/end_pfn to a struct page pointer.
 197          */
 198         start_pg = pfn_to_page(start_pfn - 1) + 1;
 199         end_pg = pfn_to_page(end_pfn - 1) + 1;
 200
 201         /*
 202          * Convert to physical addresses, and round start upwards and end
 203          * downwards.
 204          */
 205         pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
 206         pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
 207
 208         /*
 209          * If there are free pages between these, free the section of the
 210          * memmap array.
 211          */
 212         if (pg < pgend)
 213                 free_bootmem(pg, pgend - pg);
 214 }
 215
 216 /*
 217  * The mem_map array can get very big. Free the unused area of the memory map.
 218  */
 219 static void __init free_unused_memmap(void)
 220 {
 221         unsigned long start, prev_end = 0;
 222         struct memblock_region *reg;
 223
 224         for_each_memblock(memory, reg) {
 225                 start = __phys_to_pfn(reg->base);
 226
 227 #ifdef CONFIG_SPARSEMEM
 228                 /*
 229                  * Take care not to free memmap entries that don't exist due
 230                  * to SPARSEMEM sections which aren't present.
 231                  */
 232                 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
 233 #endif
 234                 /*
 235                  * If we had a previous bank, and there is a space between the
 236                  * current bank and the previous, free it.
 237                  */
 238                 if (prev_end && prev_end < start)
 239                         free_memmap(prev_end, start);
 240
 241                 /*
 242                  * Align up here since the VM subsystem insists that the
 243                  * memmap entries are valid from the bank end aligned to
 244                  * MAX_ORDER_NR_PAGES.
 245                  */
 246                 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
 247                                  MAX_ORDER_NR_PAGES);
 248         }
 249
 250 #ifdef CONFIG_SPARSEMEM
 251         if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
 252                 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
 253 #endif
 254 }
 255 #endif  /* !CONFIG_SPARSEMEM_VMEMMAP */
 256
 257 /*
 258  * mem_init() marks the free areas in the mem_map and tells us how much memory
 259  * is free.  This is done after various parts of the system have claimed their
 260  * memory after the kernel image.
 261  */
 262 void __init mem_init(void)
 263 {
 264         arm64_swiotlb_init();
 265
 266         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 267
 268 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 269         free_unused_memmap();
 270 #endif
 271         /* this will put all unused low memory onto the freelists */
 272         free_all_bootmem();
 273
 274         mem_init_print_info(NULL);
 275
 276 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 277 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 278 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 279
 280         pr_notice("Virtual kernel memory layout:\n"
 281                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 282 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 283                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 284 #endif
 285                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 286                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 287                   "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 288                   "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 289                   "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
 290                   MLM(VMALLOC_START, VMALLOC_END),
 291 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 292                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 293                       (unsigned long)virt_to_page(high_memory)),
 294 #endif
 295                   MLM(MODULES_VADDR, MODULES_END),
 296                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 297
 298                   MLK_ROUNDUP(__init_begin, __init_end),
 299                   MLK_ROUNDUP(_text, _etext),
 300                   MLK_ROUNDUP(_sdata, _edata));
 301
 302 #undef MLK
 303 #undef MLM
 304 #undef MLK_ROUNDUP
 305
 306         /*
 307          * Check boundaries twice: Some fundamental inconsistencies can be
 308          * detected at build time already.
 309          */
 310 #ifdef CONFIG_COMPAT
 311         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 312 #endif
 313         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 314         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 315
 316         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 317                 extern int sysctl_overcommit_memory;
 318                 /*
 319                  * On a machine this small we won't get anywhere without
 320                  * overcommit, so turn it on by default.
 321                  */
 322                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 323         }
 324 }
 325
 326 void free_initmem(void)
 327 {
 328         free_initmem_default(0);
 329 }
 330
 331 #ifdef CONFIG_BLK_DEV_INITRD
 332
 333 static int keep_initrd;
 334
 335 void free_initrd_mem(unsigned long start, unsigned long end)
 336 {
 337         if (!keep_initrd)
 338                 free_reserved_area((void *)start, (void *)end, 0, "initrd");
 339 }
 340
 341 static int __init keepinitrd_setup(char *__unused)
 342 {
 343         keep_initrd = 1;
 344         return 1;
 345 }
 346
 347 __setup("keepinitrd", keepinitrd_setup);
 348 #endif