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 #include <linux/efi.h>
  36 #include <linux/swiotlb.h>
  37
  38 #include <asm/fixmap.h>
  39 #include <asm/memory.h>
  40 #include <asm/sections.h>
  41 #include <asm/setup.h>
  42 #include <asm/sizes.h>
  43 #include <asm/tlb.h>
  44 #include <asm/alternative.h>
  45
  46 #include "mm.h"
  47
  48 phys_addr_t memstart_addr __read_mostly = 0;
  49 phys_addr_t arm64_dma_phys_limit __read_mostly;
  50
  51 #ifdef CONFIG_BLK_DEV_INITRD
  52 static int __init early_initrd(char *p)
  53 {
  54         unsigned long start, size;
  55         char *endp;
  56
  57         start = memparse(p, &endp);
  58         if (*endp == ',') {
  59                 size = memparse(endp + 1, NULL);
  60
  61                 initrd_start = (unsigned long)__va(start);
  62                 initrd_end = (unsigned long)__va(start + size);
  63         }
  64         return 0;
  65 }
  66 early_param("initrd", early_initrd);
  67 #endif
  68
  69 /*
  70  * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
  71  * currently assumes that for memory starting above 4G, 32-bit devices will
  72  * use a DMA offset.
  73  */
  74 static phys_addr_t __init max_zone_dma_phys(void)
  75 {
  76         phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
  77         return min(offset + (1ULL << 32), memblock_end_of_DRAM());
  78 }
  79
  80 static void __init zone_sizes_init(unsigned long min, unsigned long max)
  81 {
  82         struct memblock_region *reg;
  83         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  84         unsigned long max_dma = min;
  85
  86         memset(zone_size, 0, sizeof(zone_size));
  87
  88         /* 4GB maximum for 32-bit only capable devices */
  89 #ifdef CONFIG_ZONE_DMA
  90         max_dma = PFN_DOWN(arm64_dma_phys_limit);
  91         zone_size[ZONE_DMA] = max_dma - min;
  92 #endif
  93         zone_size[ZONE_NORMAL] = max - max_dma;
  94
  95         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  96
  97         for_each_memblock(memory, reg) {
  98                 unsigned long start = memblock_region_memory_base_pfn(reg);
  99                 unsigned long end = memblock_region_memory_end_pfn(reg);
 100
 101                 if (start >= max)
 102                         continue;
 103
 104 #ifdef CONFIG_ZONE_DMA
 105                 if (start < max_dma) {
 106                         unsigned long dma_end = min(end, max_dma);
 107                         zhole_size[ZONE_DMA] -= dma_end - start;
 108                 }
 109 #endif
 110                 if (end > max_dma) {
 111                         unsigned long normal_end = min(end, max);
 112                         unsigned long normal_start = max(start, max_dma);
 113                         zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
 114                 }
 115         }
 116
 117         free_area_init_node(0, zone_size, min, zhole_size);
 118 }
 119
 120 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 121 int pfn_valid(unsigned long pfn)
 122 {
 123         return memblock_is_map_memory(pfn << PAGE_SHIFT);
 124 }
 125 EXPORT_SYMBOL(pfn_valid);
 126 #endif
 127
 128 #ifndef CONFIG_SPARSEMEM
 129 static void __init arm64_memory_present(void)
 130 {
 131 }
 132 #else
 133 static void __init arm64_memory_present(void)
 134 {
 135         struct memblock_region *reg;
 136
 137         for_each_memblock(memory, reg)
 138                 memory_present(0, memblock_region_memory_base_pfn(reg),
 139                                memblock_region_memory_end_pfn(reg));
 140 }
 141 #endif
 142
 143 static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
 144
 145 /*
 146  * Limit the memory size that was specified via FDT.
 147  */
 148 static int __init early_mem(char *p)
 149 {
 150         if (!p)
 151                 return 1;
 152
 153         memory_limit = memparse(p, &p) & PAGE_MASK;
 154         pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
 155
 156         return 0;
 157 }
 158 early_param("mem", early_mem);
 159
 160 void __init arm64_memblock_init(void)
 161 {
 162         memblock_enforce_memory_limit(memory_limit);
 163
 164         /*
 165          * Register the kernel text, kernel data, initrd, and initial
 166          * pagetables with memblock.
 167          */
 168         memblock_reserve(__pa(_text), _end - _text);
 169 #ifdef CONFIG_BLK_DEV_INITRD
 170         if (initrd_start)
 171                 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
 172 #endif
 173
 174         early_init_fdt_scan_reserved_mem();
 175
 176         /* 4GB maximum for 32-bit only capable devices */
 177         if (IS_ENABLED(CONFIG_ZONE_DMA))
 178                 arm64_dma_phys_limit = max_zone_dma_phys();
 179         else
 180                 arm64_dma_phys_limit = PHYS_MASK + 1;
 181         dma_contiguous_reserve(arm64_dma_phys_limit);
 182
 183         memblock_allow_resize();
 184         memblock_dump_all();
 185 }
 186
 187 void __init bootmem_init(void)
 188 {
 189         unsigned long min, max;
 190
 191         min = PFN_UP(memblock_start_of_DRAM());
 192         max = PFN_DOWN(memblock_end_of_DRAM());
 193
 194         early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT);
 195
 196         /*
 197          * Sparsemem tries to allocate bootmem in memory_present(), so must be
 198          * done after the fixed reservations.
 199          */
 200         arm64_memory_present();
 201
 202         sparse_init();
 203         zone_sizes_init(min, max);
 204
 205         high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
 206         max_pfn = max_low_pfn = max;
 207 }
 208
 209 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 210 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 211 {
 212         struct page *start_pg, *end_pg;
 213         unsigned long pg, pgend;
 214
 215         /*
 216          * Convert start_pfn/end_pfn to a struct page pointer.
 217          */
 218         start_pg = pfn_to_page(start_pfn - 1) + 1;
 219         end_pg = pfn_to_page(end_pfn - 1) + 1;
 220
 221         /*
 222          * Convert to physical addresses, and round start upwards and end
 223          * downwards.
 224          */
 225         pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
 226         pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
 227
 228         /*
 229          * If there are free pages between these, free the section of the
 230          * memmap array.
 231          */
 232         if (pg < pgend)
 233                 free_bootmem(pg, pgend - pg);
 234 }
 235
 236 /*
 237  * The mem_map array can get very big. Free the unused area of the memory map.
 238  */
 239 static void __init free_unused_memmap(void)
 240 {
 241         unsigned long start, prev_end = 0;
 242         struct memblock_region *reg;
 243
 244         for_each_memblock(memory, reg) {
 245                 start = __phys_to_pfn(reg->base);
 246
 247 #ifdef CONFIG_SPARSEMEM
 248                 /*
 249                  * Take care not to free memmap entries that don't exist due
 250                  * to SPARSEMEM sections which aren't present.
 251                  */
 252                 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
 253 #endif
 254                 /*
 255                  * If we had a previous bank, and there is a space between the
 256                  * current bank and the previous, free it.
 257                  */
 258                 if (prev_end && prev_end < start)
 259                         free_memmap(prev_end, start);
 260
 261                 /*
 262                  * Align up here since the VM subsystem insists that the
 263                  * memmap entries are valid from the bank end aligned to
 264                  * MAX_ORDER_NR_PAGES.
 265                  */
 266                 prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size),
 267                                  MAX_ORDER_NR_PAGES);
 268         }
 269
 270 #ifdef CONFIG_SPARSEMEM
 271         if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
 272                 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
 273 #endif
 274 }
 275 #endif  /* !CONFIG_SPARSEMEM_VMEMMAP */
 276
 277 /*
 278  * mem_init() marks the free areas in the mem_map and tells us how much memory
 279  * is free.  This is done after various parts of the system have claimed their
 280  * memory after the kernel image.
 281  */
 282 void __init mem_init(void)
 283 {
 284         swiotlb_init(1);
 285
 286         set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
 287
 288 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 289         free_unused_memmap();
 290 #endif
 291         /* this will put all unused low memory onto the freelists */
 292         free_all_bootmem();
 293
 294         mem_init_print_info(NULL);
 295
 296 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 297 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 298 #define MLG(b, t) b, t, ((t) - (b)) >> 30
 299 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 300
 301         pr_notice("Virtual kernel memory layout:\n"
 302 #ifdef CONFIG_KASAN
 303                   "    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n"
 304 #endif
 305                   "    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n"
 306 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 307                   "    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n"
 308                   "              0x%16lx - 0x%16lx   (%6ld MB actual)\n"
 309 #endif
 310                   "    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n"
 311                   "    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 312                   "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 313                   "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
 314                   "      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n"
 315                   "      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n"
 316                   "      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
 317 #ifdef CONFIG_KASAN
 318                   MLG(KASAN_SHADOW_START, KASAN_SHADOW_END),
 319 #endif
 320                   MLG(VMALLOC_START, VMALLOC_END),
 321 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 322                   MLG((unsigned long)vmemmap,
 323                       (unsigned long)vmemmap + VMEMMAP_SIZE),
 324                   MLM((unsigned long)virt_to_page(PAGE_OFFSET),
 325                       (unsigned long)virt_to_page(high_memory)),
 326 #endif
 327                   MLK(FIXADDR_START, FIXADDR_TOP),
 328                   MLM(PCI_IO_START, PCI_IO_END),
 329                   MLM(MODULES_VADDR, MODULES_END),
 330                   MLM(PAGE_OFFSET, (unsigned long)high_memory),
 331                   MLK_ROUNDUP(__init_begin, __init_end),
 332                   MLK_ROUNDUP(_text, _etext),
 333                   MLK_ROUNDUP(_sdata, _edata));
 334
 335 #undef MLK
 336 #undef MLM
 337 #undef MLK_ROUNDUP
 338
 339         /*
 340          * Check boundaries twice: Some fundamental inconsistencies can be
 341          * detected at build time already.
 342          */
 343 #ifdef CONFIG_COMPAT
 344         BUILD_BUG_ON(TASK_SIZE_32                       > TASK_SIZE_64);
 345 #endif
 346         BUILD_BUG_ON(TASK_SIZE_64                       > MODULES_VADDR);
 347         BUG_ON(TASK_SIZE_64                             > MODULES_VADDR);
 348
 349         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 350                 extern int sysctl_overcommit_memory;
 351                 /*
 352                  * On a machine this small we won't get anywhere without
 353                  * overcommit, so turn it on by default.
 354                  */
 355                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 356         }
 357 }
 358
 359 void free_initmem(void)
 360 {
 361         fixup_init();
 362         free_initmem_default(0);
 363 }
 364
 365 #ifdef CONFIG_BLK_DEV_INITRD
 366
 367 static int keep_initrd __initdata;
 368
 369 void __init free_initrd_mem(unsigned long start, unsigned long end)
 370 {
 371         if (!keep_initrd)
 372                 free_reserved_area((void *)start, (void *)end, 0, "initrd");
 373 }
 374
 375 static int __init keepinitrd_setup(char *__unused)
 376 {
 377         keep_initrd = 1;
 378         return 1;
 379 }
 380
 381 __setup("keepinitrd", keepinitrd_setup);
 382 #endif