linux/arch/mn10300/mm/init.c
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   1/* MN10300 Memory management initialisation
   2 *
   3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
   4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   5 * Modified by David Howells (dhowells@redhat.com)
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public Licence
   9 * as published by the Free Software Foundation; either version
  10 * 2 of the Licence, or (at your option) any later version.
  11 */
  12#include <linux/signal.h>
  13#include <linux/sched.h>
  14#include <linux/kernel.h>
  15#include <linux/errno.h>
  16#include <linux/string.h>
  17#include <linux/types.h>
  18#include <linux/ptrace.h>
  19#include <linux/mman.h>
  20#include <linux/slab.h>
  21#include <linux/fs.h>
  22#include <linux/mm.h>
  23#include <linux/swap.h>
  24#include <linux/smp.h>
  25#include <linux/init.h>
  26#include <linux/initrd.h>
  27#include <linux/highmem.h>
  28#include <linux/pagemap.h>
  29#include <linux/bootmem.h>
  30
  31#include <asm/processor.h>
  32#include <asm/system.h>
  33#include <asm/uaccess.h>
  34#include <asm/pgtable.h>
  35#include <asm/pgalloc.h>
  36#include <asm/dma.h>
  37#include <asm/tlb.h>
  38#include <asm/sections.h>
  39
  40DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  41
  42unsigned long highstart_pfn, highend_pfn;
  43
  44/*
  45 * set up paging
  46 */
  47void __init paging_init(void)
  48{
  49        unsigned long zones_size[MAX_NR_ZONES] = {0,};
  50        pte_t *ppte;
  51        int loop;
  52
  53        /* main kernel space -> RAM mapping is handled as 1:1 transparent by
  54         * the MMU */
  55        memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
  56        memset(kernel_vmalloc_ptes, 0, sizeof(kernel_vmalloc_ptes));
  57
  58        /* load the VMALLOC area PTE table addresses into the kernel PGD */
  59        ppte = kernel_vmalloc_ptes;
  60        for (loop = VMALLOC_START / (PAGE_SIZE * PTRS_PER_PTE);
  61             loop < VMALLOC_END / (PAGE_SIZE * PTRS_PER_PTE);
  62             loop++
  63             ) {
  64                set_pgd(swapper_pg_dir + loop, __pgd(__pa(ppte) | _PAGE_TABLE));
  65                ppte += PAGE_SIZE / sizeof(pte_t);
  66        }
  67
  68        /* declare the sizes of the RAM zones (only use the normal zone) */
  69        zones_size[ZONE_NORMAL] =
  70                contig_page_data.bdata->node_low_pfn -
  71                contig_page_data.bdata->node_min_pfn;
  72
  73        /* pass the memory from the bootmem allocator to the main allocator */
  74        free_area_init(zones_size);
  75
  76        __flush_tlb_all();
  77}
  78
  79/*
  80 * transfer all the memory from the bootmem allocator to the runtime allocator
  81 */
  82void __init mem_init(void)
  83{
  84        int codesize, reservedpages, datasize, initsize;
  85        int tmp;
  86
  87        if (!mem_map)
  88                BUG();
  89
  90#define START_PFN       (contig_page_data.bdata->node_min_pfn)
  91#define MAX_LOW_PFN     (contig_page_data.bdata->node_low_pfn)
  92
  93        max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
  94        high_memory = (void *) __va(MAX_LOW_PFN * PAGE_SIZE);
  95
  96        /* clear the zero-page */
  97        memset(empty_zero_page, 0, PAGE_SIZE);
  98
  99        /* this will put all low memory onto the freelists */
 100        totalram_pages += free_all_bootmem();
 101
 102        reservedpages = 0;
 103        for (tmp = 0; tmp < num_physpages; tmp++)
 104                if (PageReserved(&mem_map[tmp]))
 105                        reservedpages++;
 106
 107        codesize =  (unsigned long) &_etext - (unsigned long) &_stext;
 108        datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 109        initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 110
 111        printk(KERN_INFO
 112               "Memory: %luk/%luk available"
 113               " (%dk kernel code, %dk reserved, %dk data, %dk init,"
 114               " %ldk highmem)\n",
 115               (unsigned long) nr_free_pages() << (PAGE_SHIFT - 10),
 116               max_mapnr << (PAGE_SHIFT - 10),
 117               codesize >> 10,
 118               reservedpages << (PAGE_SHIFT - 10),
 119               datasize >> 10,
 120               initsize >> 10,
 121               (unsigned long) (totalhigh_pages << (PAGE_SHIFT - 10))
 122               );
 123}
 124
 125/*
 126 *
 127 */
 128void free_init_pages(char *what, unsigned long begin, unsigned long end)
 129{
 130        unsigned long addr;
 131
 132        for (addr = begin; addr < end; addr += PAGE_SIZE) {
 133                ClearPageReserved(virt_to_page(addr));
 134                init_page_count(virt_to_page(addr));
 135                memset((void *) addr, 0xcc, PAGE_SIZE);
 136                free_page(addr);
 137                totalram_pages++;
 138        }
 139        printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 140}
 141
 142/*
 143 * recycle memory containing stuff only required for initialisation
 144 */
 145void free_initmem(void)
 146{
 147        free_init_pages("unused kernel memory",
 148                        (unsigned long) &__init_begin,
 149                        (unsigned long) &__init_end);
 150}
 151
 152/*
 153 * dispose of the memory on which the initial ramdisk resided
 154 */
 155#ifdef CONFIG_BLK_DEV_INITRD
 156void free_initrd_mem(unsigned long start, unsigned long end)
 157{
 158        free_init_pages("initrd memory", start, end);
 159}
 160#endif
 161