init.c 3.8 KB

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  1. /*
  2. * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  3. *
  4. * This program is free software; you can redistribute it and/or modify
  5. * it under the terms of the GNU General Public License version 2 as
  6. * published by the Free Software Foundation.
  7. */
  8. #include <linux/kernel.h>
  9. #include <linux/mm.h>
  10. #include <linux/bootmem.h>
  11. #include <linux/memblock.h>
  12. #include <linux/swap.h>
  13. #include <linux/module.h>
  14. #include <asm/page.h>
  15. #include <asm/pgalloc.h>
  16. #include <asm/sections.h>
  17. #include <asm/arcregs.h>
  18. pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
  19. char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
  20. EXPORT_SYMBOL(empty_zero_page);
  21. /* Default tot mem from .config */
  22. static unsigned long arc_mem_sz = 0x20000000; /* some default */
  23. /* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
  24. static int __init setup_mem_sz(char *str)
  25. {
  26. arc_mem_sz = memparse(str, NULL) & PAGE_MASK;
  27. /* early console might not be setup yet - it will show up later */
  28. pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(arc_mem_sz));
  29. return 0;
  30. }
  31. early_param("mem", setup_mem_sz);
  32. void __init early_init_dt_add_memory_arch(u64 base, u64 size)
  33. {
  34. arc_mem_sz = size & PAGE_MASK;
  35. pr_info("Memory size set via devicetree %ldM\n", TO_MB(arc_mem_sz));
  36. }
  37. /*
  38. * First memory setup routine called from setup_arch()
  39. * 1. setup swapper's mm @init_mm
  40. * 2. Count the pages we have and setup bootmem allocator
  41. * 3. zone setup
  42. */
  43. void __init setup_arch_memory(void)
  44. {
  45. unsigned long zones_size[MAX_NR_ZONES] = { 0, 0 };
  46. unsigned long end_mem = CONFIG_LINUX_LINK_BASE + arc_mem_sz;
  47. init_mm.start_code = (unsigned long)_text;
  48. init_mm.end_code = (unsigned long)_etext;
  49. init_mm.end_data = (unsigned long)_edata;
  50. init_mm.brk = (unsigned long)_end;
  51. /*
  52. * We do it here, so that memory is correctly instantiated
  53. * even if "mem=xxx" cmline over-ride is given and/or
  54. * DT has memory node. Each causes an update to @arc_mem_sz
  55. * and we finally add memory one here
  56. */
  57. memblock_add(CONFIG_LINUX_LINK_BASE, arc_mem_sz);
  58. /*------------- externs in mm need setting up ---------------*/
  59. /* first page of system - kernel .vector starts here */
  60. min_low_pfn = PFN_DOWN(CONFIG_LINUX_LINK_BASE);
  61. /* Last usable page of low mem (no HIGHMEM yet for ARC port) */
  62. max_low_pfn = max_pfn = PFN_DOWN(end_mem);
  63. max_mapnr = max_low_pfn - min_low_pfn;
  64. /*------------- reserve kernel image -----------------------*/
  65. memblock_reserve(CONFIG_LINUX_LINK_BASE,
  66. __pa(_end) - CONFIG_LINUX_LINK_BASE);
  67. memblock_dump_all();
  68. /*-------------- node setup --------------------------------*/
  69. memset(zones_size, 0, sizeof(zones_size));
  70. zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
  71. /*
  72. * We can't use the helper free_area_init(zones[]) because it uses
  73. * PAGE_OFFSET to compute the @min_low_pfn which would be wrong
  74. * when our kernel doesn't start at PAGE_OFFSET, i.e.
  75. * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE
  76. */
  77. free_area_init_node(0, /* node-id */
  78. zones_size, /* num pages per zone */
  79. min_low_pfn, /* first pfn of node */
  80. NULL); /* NO holes */
  81. }
  82. /*
  83. * mem_init - initializes memory
  84. *
  85. * Frees up bootmem
  86. * Calculates and displays memory available/used
  87. */
  88. void __init mem_init(void)
  89. {
  90. high_memory = (void *)(CONFIG_LINUX_LINK_BASE + arc_mem_sz);
  91. free_all_bootmem();
  92. mem_init_print_info(NULL);
  93. }
  94. /*
  95. * free_initmem: Free all the __init memory.
  96. */
  97. void __init_refok free_initmem(void)
  98. {
  99. free_initmem_default(-1);
  100. }
  101. #ifdef CONFIG_BLK_DEV_INITRD
  102. void __init free_initrd_mem(unsigned long start, unsigned long end)
  103. {
  104. free_reserved_area((void *)start, (void *)end, -1, "initrd");
  105. }
  106. #endif
  107. #ifdef CONFIG_OF_FLATTREE
  108. void __init early_init_dt_setup_initrd_arch(unsigned long start,
  109. unsigned long end)
  110. {
  111. pr_err("%s(%lx, %lx)\n", __func__, start, end);
  112. }
  113. #endif /* CONFIG_OF_FLATTREE */