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(u64 start, u64 end)
  48 {
  49         phys_initrd_start = start;
  50         phys_initrd_size = end - start;
  51 }
  52
  53 static int __init early_initrd(char *p)
  54 {
  55         unsigned long start, size;
  56         char *endp;
  57
  58         start = memparse(p, &endp);
  59         if (*endp == ',') {
  60                 size = memparse(endp + 1, NULL);
  61
  62                 phys_initrd_start = start;
  63                 phys_initrd_size = size;
  64         }
  65         return 0;
  66 }
  67 early_param("initrd", early_initrd);
  68
  69 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
  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_dma32 = min;
  76
  77         memset(zone_size, 0, sizeof(zone_size));
  78
  79 #ifdef CONFIG_ZONE_DMA32
  80         /* 4GB maximum for 32-bit only capable devices */
  81         max_dma32 = max(min, min(max, MAX_DMA32_PFN));
  82         zone_size[ZONE_DMA32] = max_dma32 - min;
  83 #endif
  84         zone_size[ZONE_NORMAL] = max - max_dma32;
  85
  86         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  87
  88         for_each_memblock(memory, reg) {
  89                 unsigned long start = memblock_region_memory_base_pfn(reg);
  90                 unsigned long end = memblock_region_memory_end_pfn(reg);
  91
  92                 if (start >= max)
  93                         continue;
  94 #ifdef CONFIG_ZONE_DMA32
  95                 if (start < max_dma32) {
  96                         unsigned long dma_end = min(end, max_dma32);
  97                         zhole_size[ZONE_DMA32] -= dma_end - start;
  98                 }
  99 #endif
 100                 if (end > max_dma32) {
 101                         unsigned long normal_end = min(end, max);
 102                         unsigned long normal_start = max(start, max_dma32);
 103                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
 104                 }
 105         }
 106
 107         free_area_init_node(0, zone_size, min, zhole_size);
 108 }
 109
 110 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 111 int pfn_valid(unsigned long pfn)
 112 {
 113         return memblock_is_memory(pfn << PAGE_SHIFT);
 114 }
 115 EXPORT_SYMBOL(pfn_valid);
 116 #endif
 117
 118 #ifndef CONFIG_SPARSEMEM
 119 static void arm64_memory_present(void)
 120 {
 121 }
 122 #else
 123 static void arm64_memory_present(void)
 124 {
 125         struct memblock_region *reg;
 126
 127         for_each_memblock(memory, reg)
 128                 memory_present(0, memblock_region_memory_base_pfn(reg),
 129                                memblock_region_memory_end_pfn(reg));
 130 }
 131 #endif
 132
 133 void __init arm64_memblock_init(void)
 134 {
 135         u64 *reserve_map, base, size;
 136
 137         /* Register the kernel text, kernel data and initrd with memblock */
 138         memblock_reserve(__pa(_text), _end - _text);
 139 #ifdef CONFIG_BLK_DEV_INITRD
 140         if (phys_initrd_size) {
 141                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 142
 143                 /* Now convert initrd to virtual addresses */
 144                 initrd_start = __phys_to_virt(phys_initrd_start);
 145                 initrd_end = initrd_start + phys_initrd_size;
 146         }
 147 #endif
 148
 149         /*
 150          * Reserve the page tables.  These are already in use,
 151          * and can only be in node 0.
 152          */
 153         memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
 154         memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
 155
 156         /* Reserve the dtb region */
 157         memblock_reserve(virt_to_phys(initial_boot_params),
 158                          be32_to_cpu(initial_boot_params->totalsize));
 159
 160         /*
 161          * Process the reserve map.  This will probably overlap the initrd
 162          * and dtb locations which are already reserved, but overlapping
 163          * doesn't hurt anything
 164          */
 165         reserve_map = ((void*)initial_boot_params) +
 166                         be32_to_cpu(initial_boot_params->off_mem_rsvmap);
 167         while (1) {
 168                 base = be64_to_cpup(reserve_map++);
 169                 size = be64_to_cpup(reserve_map++);
 170                 if (!size)
 171                         break;
 172                 memblock_reserve(base, size);
 173         }
 174
 175         memblock_allow_resize();
 176         memblock_dump_all();
 177 }
 178
 179 void __init bootmem_init(void)
 180 {
 181         unsigned long min, max;
 182
 183         min = PFN_UP(memblock_start_of_DRAM());
 184         max = PFN_DOWN(memblock_end_of_DRAM());
 185
 186         /*
 187          * Sparsemem tries to allocate bootmem in memory_present(), so must be
 188          * done after the fixed reservations.
 189          */
 190         arm64_memory_present();
 191
 192         sparse_init();
 193         zone_sizes_init(min, max);
 194
 195         high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
 196         max_pfn = max_low_pfn = max;
 197 }
 198
 199 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 200 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 201 {
 202         struct page *start_pg, *end_pg;
 203         unsigned long pg, pgend;
 204
 205         /*
 206          * Convert start_pfn/end_pfn to a struct page pointer.
 207          */
 208         start_pg = pfn_to_page(start_pfn - 1) + 1;
 209         end_pg = pfn_to_page(end_pfn - 1) + 1;
 210
 211         /*
 212          * Convert to physical addresses, and round start upwards and end
 213          * downwards.
 214          */
 215         pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
 216         pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
 217
 218         /*
 219          * If there are free pages between these, free the section of the
 220          * memmap array.
 221          */
 222         if (pg < pgend)
 223                 free_bootmem(pg, pgend - pg);
 224 }
 225
 226 /*
 227  * The mem_map array can get very big. Free the unused area of the memory map.
 228  */
 229 static void __init free_unused_memmap(void)
 230 {
 231         unsigned long start, prev_end = 0;
 232         struct memblock_region *reg;
 233
 234         for_each_memblock(memory, reg) {
 235                 start = __phys_to_pfn(reg->base);
 236
 237 #ifdef CONFIG_SPARSEMEM
 238                 /*
 239                  * Take care not to free memmap entries that don't exist due
 240                  * to SPARSEMEM sections which aren't present.
 241                  */
 242                 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
 243 #endif
 244                 /*
 245                  * If we had a previous bank, and there is a space between the
 246                  * current bank and the previous, free it.
 247                  */
 248                 if (prev_end && prev_end < start)
 249                         free_memmap(prev_end, start);
 250
 251                 /*
 252                  * Align up here since the VM subsystem insists that the
 253                  * memmap entries are valid from the bank end aligned to
 254                  * MAX_ORDER_NR_PAGES.
 255                  */
 256                 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
 257                                  MAX_ORDER_NR_PAGES);
 258         }
 259
 260 #ifdef CONFIG_SPARSEMEM
 261         if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
 262                 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
 263 #endif
 264 }
 265 #endif  /* !CONFIG_SPARSEMEM_VMEMMAP */
 266
 267 /*
 268  * mem_init() marks the free areas in the mem_map and tells us how much memory
 269  * is free.  This is done after various parts of the system have claimed their
 270  * memory after the kernel image.
 271  */
 272 void __init mem_init(void)
 273 {
 274         arm64_swiotlb_init();
 275
 276         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 277
 278 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 279         free_unused_memmap();
 280 #endif
 281         /* this will put all unused low memory onto the freelists */
 282         free_all_bootmem();
 283
 284         mem_init_print_info(NULL);
 285
 286 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 287 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 288 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 289
 290         pr_notice("Virtual kernel memory layout:\n"
 291                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 292 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 293                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 294 #endif
 295                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 296                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 297                   "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 298                   "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
 299                   "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
 300                   MLM(VMALLOC_START, VMALLOC_END),
 301 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 302                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 303                       (unsigned long)virt_to_page(high_memory)),
 304 #endif
 305                   MLM(MODULES_VADDR, MODULES_END),
 306                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 307
 308                   MLK_ROUNDUP(__init_begin, __init_end),
 309                   MLK_ROUNDUP(_text, _etext),
 310                   MLK_ROUNDUP(_sdata, _edata));
 311
 312 #undef MLK
 313 #undef MLM
 314 #undef MLK_ROUNDUP
 315
 316         /*
 317          * Check boundaries twice: Some fundamental inconsistencies can be
 318          * detected at build time already.
 319          */
 320 #ifdef CONFIG_COMPAT
 321         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 322 #endif
 323         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 324         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 325
 326         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 327                 extern int sysctl_overcommit_memory;
 328                 /*
 329                  * On a machine this small we won't get anywhere without
 330                  * overcommit, so turn it on by default.
 331                  */
 332                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 333         }
 334 }
 335
 336 void free_initmem(void)
 337 {
 338         free_initmem_default(0);
 339 }
 340
 341 #ifdef CONFIG_BLK_DEV_INITRD
 342
 343 static int keep_initrd;
 344
 345 void free_initrd_mem(unsigned long start, unsigned long end)
 346 {
 347         if (!keep_initrd)
 348                 free_reserved_area((void *)start, (void *)end, 0, "initrd");
 349 }
 350
 351 static int __init keepinitrd_setup(char *__unused)
 352 {
 353         keep_initrd = 1;
 354         return 1;
 355 }
 356
 357 __setup("keepinitrd", keepinitrd_setup);
 358 #endif