arch/m32r/mm/init.c

   1 /*
   2  *  linux/arch/m32r/mm/init.c
   3  *
   4  *  Copyright (c) 2001, 2002  Hitoshi Yamamoto
   5  *
   6  *  Some code taken from sh version.
   7  *    Copyright (C) 1999  Niibe Yutaka
   8  *    Based on linux/arch/i386/mm/init.c:
   9  *      Copyright (C) 1995  Linus Torvalds
  10  */
  11
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/mm.h>
  15 #include <linux/pagemap.h>
  16 #include <linux/bootmem.h>
  17 #include <linux/swap.h>
  18 #include <linux/highmem.h>
  19 #include <linux/bitops.h>
  20 #include <linux/nodemask.h>
  21 #include <linux/pfn.h>
  22 #include <asm/types.h>
  23 #include <asm/processor.h>
  24 #include <asm/page.h>
  25 #include <asm/pgtable.h>
  26 #include <asm/pgalloc.h>
  27 #include <asm/mmu_context.h>
  28 #include <asm/setup.h>
  29 #include <asm/tlb.h>
  30
  31 /* References to section boundaries */
  32 extern char _text, _etext, _edata;
  33 extern char __init_begin, __init_end;
  34
  35 pgd_t swapper_pg_dir[1024];
  36
  37 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  38
  39 /*
  40  * Cache of MMU context last used.
  41  */
  42 #ifndef CONFIG_SMP
  43 unsigned long mmu_context_cache_dat;
  44 #else
  45 unsigned long mmu_context_cache_dat[NR_CPUS];
  46 #endif
  47 static unsigned long hole_pages;
  48
  49 /*
  50  * function prototype
  51  */
  52 void __init paging_init(void);
  53 void __init mem_init(void);
  54 void free_initmem(void);
  55 #ifdef CONFIG_BLK_DEV_INITRD
  56 void free_initrd_mem(unsigned long, unsigned long);
  57 #endif
  58
  59 /* It'd be good if these lines were in the standard header file. */
  60 #define START_PFN(nid)          (NODE_DATA(nid)->bdata->node_min_pfn)
  61 #define MAX_LOW_PFN(nid)        (NODE_DATA(nid)->bdata->node_low_pfn)
  62
  63 #ifndef CONFIG_DISCONTIGMEM
  64 unsigned long __init zone_sizes_init(void)
  65 {
  66         unsigned long  zones_size[MAX_NR_ZONES] = {0, };
  67         unsigned long  max_dma;
  68         unsigned long  low;
  69         unsigned long  start_pfn;
  70
  71 #ifdef CONFIG_MMU
  72         start_pfn = START_PFN(0);
  73         max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
  74         low = MAX_LOW_PFN(0);
  75
  76         if (low < max_dma){
  77                 zones_size[ZONE_DMA] = low - start_pfn;
  78                 zones_size[ZONE_NORMAL] = 0;
  79         } else {
  80                 zones_size[ZONE_DMA] = low - start_pfn;
  81                 zones_size[ZONE_NORMAL] = low - max_dma;
  82         }
  83 #else
  84         zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
  85         zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
  86         start_pfn = __MEMORY_START >> PAGE_SHIFT;
  87 #endif /* CONFIG_MMU */
  88
  89         free_area_init_node(0, zones_size, start_pfn, 0);
  90
  91         return 0;
  92 }
  93 #else   /* CONFIG_DISCONTIGMEM */
  94 extern unsigned long zone_sizes_init(void);
  95 #endif  /* CONFIG_DISCONTIGMEM */
  96
  97 /*======================================================================*
  98  * paging_init() : sets up the page tables
  99  *======================================================================*/
 100 void __init paging_init(void)
 101 {
 102 #ifdef CONFIG_MMU
 103         int  i;
 104         pgd_t *pg_dir;
 105
 106         /* We don't need kernel mapping as hardware support that. */
 107         pg_dir = swapper_pg_dir;
 108
 109         for (i = 0 ; i < USER_PTRS_PER_PGD * 2 ; i++)
 110                 pgd_val(pg_dir[i]) = 0;
 111 #endif /* CONFIG_MMU */
 112         hole_pages = zone_sizes_init();
 113 }
 114
 115 int __init reservedpages_count(void)
 116 {
 117         int reservedpages, nid, i;
 118
 119         reservedpages = 0;
 120         for_each_online_node(nid) {
 121                 unsigned long flags;
 122                 pgdat_resize_lock(NODE_DATA(nid), &flags);
 123                 for (i = 0 ; i < MAX_LOW_PFN(nid) - START_PFN(nid) ; i++)
 124                         if (PageReserved(nid_page_nr(nid, i)))
 125                                 reservedpages++;
 126                 pgdat_resize_unlock(NODE_DATA(nid), &flags);
 127         }
 128
 129         return reservedpages;
 130 }
 131
 132 /*======================================================================*
 133  * mem_init() :
 134  * orig : arch/sh/mm/init.c
 135  *======================================================================*/
 136 void __init mem_init(void)
 137 {
 138         int codesize, reservedpages, datasize, initsize;
 139         int nid;
 140 #ifndef CONFIG_MMU
 141         extern unsigned long memory_end;
 142 #endif
 143
 144         num_physpages = 0;
 145         for_each_online_node(nid)
 146                 num_physpages += MAX_LOW_PFN(nid) - START_PFN(nid) + 1;
 147
 148         num_physpages -= hole_pages;
 149
 150 #ifndef CONFIG_DISCONTIGMEM
 151         max_mapnr = num_physpages;
 152 #endif  /* CONFIG_DISCONTIGMEM */
 153
 154 #ifdef CONFIG_MMU
 155         high_memory = (void *)__va(PFN_PHYS(MAX_LOW_PFN(0)));
 156 #else
 157         high_memory = (void *)(memory_end & PAGE_MASK);
 158 #endif /* CONFIG_MMU */
 159
 160         /* clear the zero-page */
 161         memset(empty_zero_page, 0, PAGE_SIZE);
 162
 163         /* this will put all low memory onto the freelists */
 164         for_each_online_node(nid)
 165                 totalram_pages += free_all_bootmem_node(NODE_DATA(nid));
 166
 167         reservedpages = reservedpages_count() - hole_pages;
 168         codesize = (unsigned long) &_etext - (unsigned long)&_text;
 169         datasize = (unsigned long) &_edata - (unsigned long)&_etext;
 170         initsize = (unsigned long) &__init_end - (unsigned long)&__init_begin;
 171
 172         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
 173                 "%dk reserved, %dk data, %dk init)\n",
 174                 nr_free_pages() << (PAGE_SHIFT-10),
 175                 num_physpages << (PAGE_SHIFT-10),
 176                 codesize >> 10,
 177                 reservedpages << (PAGE_SHIFT-10),
 178                 datasize >> 10,
 179                 initsize >> 10);
 180 }
 181
 182 /*======================================================================*
 183  * free_initmem() :
 184  * orig : arch/sh/mm/init.c
 185  *======================================================================*/
 186 void free_initmem(void)
 187 {
 188         unsigned long addr;
 189
 190         addr = (unsigned long)(&__init_begin);
 191         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 192                 ClearPageReserved(virt_to_page(addr));
 193                 init_page_count(virt_to_page(addr));
 194                 free_page(addr);
 195                 totalram_pages++;
 196         }
 197         printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", \
 198           (int)(&__init_end - &__init_begin) >> 10);
 199 }
 200
 201 #ifdef CONFIG_BLK_DEV_INITRD
 202 /*======================================================================*
 203  * free_initrd_mem() :
 204  * orig : arch/sh/mm/init.c
 205  *======================================================================*/
 206 void free_initrd_mem(unsigned long start, unsigned long end)
 207 {
 208         unsigned long p;
 209         for (p = start; p < end; p += PAGE_SIZE) {
 210                 ClearPageReserved(virt_to_page(p));
 211                 init_page_count(virt_to_page(p));
 212                 free_page(p);
 213                 totalram_pages++;
 214         }
 215         printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 216 }
 217 #endif