arch/score/mm/init.c

   1 /*
   2  * arch/score/mm/init.c
   3  *
   4  * Score Processor version.
   5  *
   6  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   7  *  Lennox Wu <lennox.wu@sunplusct.com>
   8  *  Chen Liqin <liqin.chen@sunplusct.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see the file COPYING, or write
  22  * to the Free Software Foundation, Inc.,
  23  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  24  */
  25
  26 #include <linux/errno.h>
  27 #include <linux/bootmem.h>
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/mm.h>
  31 #include <linux/mman.h>
  32 #include <linux/pagemap.h>
  33 #include <linux/proc_fs.h>
  34 #include <linux/sched.h>
  35 #include <linux/initrd.h>
  36
  37 #include <asm/sections.h>
  38 #include <asm/tlb.h>
  39
  40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  41
  42 unsigned long empty_zero_page;
  43 EXPORT_SYMBOL_GPL(empty_zero_page);
  44
  45 static struct kcore_list kcore_mem, kcore_vmalloc;
  46
  47 static unsigned long setup_zero_page(void)
  48 {
  49         struct page *page;
  50
  51         empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, 0);
  52         if (!empty_zero_page)
  53                 panic("Oh boy, that early out of memory?");
  54
  55         page = virt_to_page((void *) empty_zero_page);
  56         SetPageReserved(page);
  57
  58         return 1UL;
  59 }
  60
  61 #ifndef CONFIG_NEED_MULTIPLE_NODES
  62 static int __init page_is_ram(unsigned long pagenr)
  63 {
  64         if (pagenr >= min_low_pfn && pagenr < max_low_pfn)
  65                 return 1;
  66         else
  67                 return 0;
  68 }
  69
  70 void __init paging_init(void)
  71 {
  72         unsigned long max_zone_pfns[MAX_NR_ZONES];
  73         unsigned long lastpfn;
  74
  75         pagetable_init();
  76         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
  77         lastpfn = max_low_pfn;
  78         free_area_init_nodes(max_zone_pfns);
  79 }
  80
  81 void __init mem_init(void)
  82 {
  83         unsigned long codesize, reservedpages, datasize, initsize;
  84         unsigned long tmp, ram = 0;
  85
  86         max_mapnr = max_low_pfn;
  87         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
  88         totalram_pages += free_all_bootmem();
  89         totalram_pages -= setup_zero_page();    /* Setup zeroed pages. */
  90         reservedpages = 0;
  91
  92         for (tmp = 0; tmp < max_low_pfn; tmp++)
  93                 if (page_is_ram(tmp)) {
  94                         ram++;
  95                         if (PageReserved(pfn_to_page(tmp)))
  96                                 reservedpages++;
  97                 }
  98
  99         num_physpages = ram;
 100         codesize = (unsigned long) &_etext - (unsigned long) &_text;
 101         datasize = (unsigned long) &_edata - (unsigned long) &_etext;
 102         initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
 103
 104         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 105         kclist_add(&kcore_vmalloc, (void *) VMALLOC_START,
 106                         VMALLOC_END - VMALLOC_START);
 107
 108         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 109                         "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 110                         (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 111                         ram << (PAGE_SHIFT-10), codesize >> 10,
 112                         reservedpages << (PAGE_SHIFT-10), datasize >> 10,
 113                         initsize >> 10,
 114                         (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 115 }
 116 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 117
 118 static void free_init_pages(const char *what, unsigned long begin, unsigned long end)
 119 {
 120         unsigned long pfn;
 121
 122         for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
 123                 struct page *page = pfn_to_page(pfn);
 124                 void *addr = phys_to_virt(PFN_PHYS(pfn));
 125
 126                 ClearPageReserved(page);
 127                 init_page_count(page);
 128                 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
 129                 __free_page(page);
 130                 totalram_pages++;
 131         }
 132         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 133 }
 134
 135 #ifdef CONFIG_BLK_DEV_INITRD
 136 void free_initrd_mem(unsigned long start, unsigned long end)
 137 {
 138         free_init_pages("initrd memory",
 139                 virt_to_phys((void *) start),
 140                 virt_to_phys((void *) end));
 141 }
 142 #endif
 143
 144 void __init_refok free_initmem(void)
 145 {
 146         free_init_pages("unused kernel memory",
 147         __pa(&__init_begin),
 148         __pa(&__init_end));
 149 }
 150
 151 unsigned long pgd_current;
 152
 153 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
 154
 155 /*
 156  * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
 157  * are constants.  So we use the variants from asm-offset.h until that gcc
 158  * will officially be retired.
 159  */
 160 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PTE_ORDER);
 161 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);