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/segment.h>
  36 #include <asm/page.h>
  37 #include <asm/pgtable.h>
  38 #include <asm/system.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 unsigned long empty_zero_page;
  46
  47 extern unsigned long memory_start;
  48 extern unsigned long memory_end;
  49
  50 /*
  51  * paging_init() continues the virtual memory environment setup which
  52  * was begun by the code in arch/head.S.
  53  * The parameters are pointers to where to stick the starting and ending
  54  * addresses of available kernel virtual memory.
  55  */
  56 void __init paging_init(void)
  57 {
  58         /*
  59          * Make sure start_mem is page aligned, otherwise bootmem and
  60          * page_alloc get different views of the world.
  61          */
  62         unsigned long end_mem   = memory_end & PAGE_MASK;
  63         unsigned long zones_size[MAX_NR_ZONES] = {0, };
  64
  65         empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
  66         memset((void *)empty_zero_page, 0, PAGE_SIZE);
  67
  68         /*
  69          * Set up SFC/DFC registers (user data space).
  70          */
  71         set_fs (USER_DS);
  72
  73         zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
  74         free_area_init(zones_size);
  75 }
  76
  77 void __init mem_init(void)
  78 {
  79         int codek = 0, datak = 0, initk = 0;
  80         unsigned long tmp;
  81         extern char _etext, _stext, _sdata, _ebss, __init_begin, __init_end;
  82         extern unsigned int _ramend, _rambase;
  83         unsigned long len = _ramend - _rambase;
  84         unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */
  85         unsigned long end_mem   = memory_end; /* DAVIDM - this must not include kernel stack at top */
  86
  87         pr_debug("Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
  88
  89         end_mem &= PAGE_MASK;
  90         high_memory = (void *) end_mem;
  91
  92         start_mem = PAGE_ALIGN(start_mem);
  93         max_mapnr = num_physpages = (((unsigned long) high_memory) - PAGE_OFFSET) >> PAGE_SHIFT;
  94
  95         /* this will put all memory onto the freelists */
  96         totalram_pages = free_all_bootmem();
  97
  98         codek = (&_etext - &_stext) >> 10;
  99         datak = (&_ebss - &_sdata) >> 10;
 100         initk = (&__init_begin - &__init_end) >> 10;
 101
 102         tmp = nr_free_pages() << PAGE_SHIFT;
 103         printk(KERN_INFO "Memory available: %luk/%luk RAM, (%dk kernel code, %dk data)\n",
 104                tmp >> 10,
 105                len >> 10,
 106                codek,
 107                datak
 108                );
 109 }
 110
 111
 112 #ifdef CONFIG_BLK_DEV_INITRD
 113 void free_initrd_mem(unsigned long start, unsigned long end)
 114 {
 115         int pages = 0;
 116         for (; start < end; start += PAGE_SIZE) {
 117                 ClearPageReserved(virt_to_page(start));
 118                 init_page_count(virt_to_page(start));
 119                 free_page(start);
 120                 totalram_pages++;
 121                 pages++;
 122         }
 123         printk (KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages * (PAGE_SIZE / 1024));
 124 }
 125 #endif
 126
 127 void free_initmem(void)
 128 {
 129 #ifdef CONFIG_RAMKERNEL
 130         unsigned long addr;
 131         extern char __init_begin, __init_end;
 132         /*
 133          * The following code should be cool even if these sections
 134          * are not page aligned.
 135          */
 136         addr = PAGE_ALIGN((unsigned long)(&__init_begin));
 137         /* next to check that the page we free is not a partial page */
 138         for (; addr + PAGE_SIZE < (unsigned long)(&__init_end); addr +=PAGE_SIZE) {
 139                 ClearPageReserved(virt_to_page(addr));
 140                 init_page_count(virt_to_page(addr));
 141                 free_page(addr);
 142                 totalram_pages++;
 143         }
 144         printk(KERN_NOTICE "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n",
 145                         (addr - PAGE_ALIGN((long) &__init_begin)) >> 10,
 146                         (int)(PAGE_ALIGN((unsigned long)(&__init_begin))),
 147                         (int)(addr - PAGE_SIZE));
 148 #endif
 149 }
 150