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