arch/m68k/mm/init_no.c

   1 /*
   2  *  linux/arch/m68knommu/mm/init.c
   3  *
   4  *  Copyright (C) 1998  D. Jeff Dionne <jeff@lineo.ca>,
   5  *                      Kenneth Albanowski <kjahds@kjahds.com>,
   6  *  Copyright (C) 2000  Lineo, Inc.  (www.lineo.com)
   7  *
   8  *  Based on:
   9  *
  10  *  linux/arch/m68k/mm/init.c
  11  *
  12  *  Copyright (C) 1995  Hamish Macdonald
  13  *
  14  *  JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
  15  *  DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
  16  */
  17
  18 #include <linux/signal.h>
  19 #include <linux/sched.h>
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/string.h>
  23 #include <linux/types.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/mman.h>
  26 #include <linux/mm.h>
  27 #include <linux/swap.h>
  28 #include <linux/init.h>
  29 #include <linux/highmem.h>
  30 #include <linux/pagemap.h>
  31 #include <linux/bootmem.h>
  32 #include <linux/gfp.h>
  33
  34 #include <asm/setup.h>
  35 #include <asm/sections.h>
  36 #include <asm/segment.h>
  37 #include <asm/page.h>
  38 #include <asm/pgtable.h>
  39 #include <asm/machdep.h>
  40
  41 /*
  42  * ZERO_PAGE is a special page that is used for zero-initialized
  43  * data and COW.
  44  */
  45 void *empty_zero_page;
  46
  47 /*
  48  * paging_init() continues the virtual memory environment setup which
  49  * was begun by the code in arch/head.S.
  50  * The parameters are pointers to where to stick the starting and ending
  51  * addresses of available kernel virtual memory.
  52  */
  53 void __init paging_init(void)
  54 {
  55         /*
  56          * Make sure start_mem is page aligned, otherwise bootmem and
  57          * page_alloc get different views of the world.
  58          */
  59         unsigned long end_mem   = memory_end & PAGE_MASK;
  60         unsigned long zones_size[MAX_NR_ZONES] = {0, };
  61
  62         empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
  63         memset(empty_zero_page, 0, PAGE_SIZE);
  64
  65         /*
  66          * Set up SFC/DFC registers (user data space).
  67          */
  68         set_fs (USER_DS);
  69
  70         zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
  71         free_area_init(zones_size);
  72 }
  73
  74 void __init mem_init(void)
  75 {
  76         int codek = 0, datak = 0, initk = 0;
  77         unsigned long tmp;
  78         unsigned long len = _ramend - _rambase;
  79         unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */
  80         unsigned long end_mem   = memory_end; /* DAVIDM - this must not include kernel stack at top */
  81
  82         pr_debug("Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
  83
  84         end_mem &= PAGE_MASK;
  85         high_memory = (void *) end_mem;
  86
  87         start_mem = PAGE_ALIGN(start_mem);
  88         max_mapnr = num_physpages = (((unsigned long) high_memory) - PAGE_OFFSET) >> PAGE_SHIFT;
  89
  90         /* this will put all memory onto the freelists */
  91         totalram_pages = free_all_bootmem();
  92
  93         codek = (_etext - _stext) >> 10;
  94         datak = (_ebss - _sdata) >> 10;
  95         initk = (__init_begin - __init_end) >> 10;
  96
  97         tmp = nr_free_pages() << PAGE_SHIFT;
  98         printk(KERN_INFO "Memory available: %luk/%luk RAM, (%dk kernel code, %dk data)\n",
  99                tmp >> 10,
 100                len >> 10,
 101                codek,
 102                datak
 103                );
 104 }
 105
 106
 107 #ifdef CONFIG_BLK_DEV_INITRD
 108 void free_initrd_mem(unsigned long start, unsigned long end)
 109 {
 110         int pages = 0;
 111         for (; start < end; start += PAGE_SIZE) {
 112                 ClearPageReserved(virt_to_page(start));
 113                 init_page_count(virt_to_page(start));
 114                 free_page(start);
 115                 totalram_pages++;
 116                 pages++;
 117         }
 118         pr_notice("Freeing initrd memory: %luk freed\n",
 119                   pages * (PAGE_SIZE / 1024));
 120 }
 121 #endif
 122
 123 void free_initmem(void)
 124 {
 125 #ifdef CONFIG_RAMKERNEL
 126         unsigned long addr;
 127         /*
 128          * The following code should be cool even if these sections
 129          * are not page aligned.
 130          */
 131         addr = PAGE_ALIGN((unsigned long) __init_begin);
 132         /* next to check that the page we free is not a partial page */
 133         for (; addr + PAGE_SIZE < ((unsigned long) __init_end); addr += PAGE_SIZE) {
 134                 ClearPageReserved(virt_to_page(addr));
 135                 init_page_count(virt_to_page(addr));
 136                 free_page(addr);
 137                 totalram_pages++;
 138         }
 139         pr_notice("Freeing unused kernel memory: %luk freed (0x%x - 0x%x)\n",
 140                         (addr - PAGE_ALIGN((unsigned long) __init_begin)) >> 10,
 141                         (int)(PAGE_ALIGN((unsigned long) __init_begin)),
 142                         (int)(addr - PAGE_SIZE));
 143 #endif
 144 }
 145