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 <asm-generic/sections.h>
  36
  37 #include <asm/tlb.h>
  38
  39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  40
  41 /*
  42  * We have up to 8 empty zeroed pages so we can map one of the right colour
  43  * when needed.
  44  */
  45 unsigned long zero_page_mask;
  46 unsigned long empty_zero_page;
  47 EXPORT_SYMBOL_GPL(empty_zero_page);
  48
  49 static struct kcore_list kcore_mem, kcore_vmalloc;
  50
  51 unsigned long setup_zero_pages(void)
  52 {
  53         unsigned int order = 0;
  54         unsigned long size;
  55         struct page *page;
  56
  57         empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
  58         if (!empty_zero_page)
  59                 panic("Oh boy, that early out of memory?");
  60
  61         page = virt_to_page((void *) empty_zero_page);
  62         split_page(page, order);
  63         while (page < virt_to_page((void *) (empty_zero_page +
  64                                              (PAGE_SIZE << order)))) {
  65                 SetPageReserved(page);
  66                 page++;
  67         }
  68
  69         size = PAGE_SIZE << order;
  70         zero_page_mask = (size - 1) & PAGE_MASK;
  71
  72         return 1UL << order;
  73 }
  74
  75 #ifndef CONFIG_NEED_MULTIPLE_NODES
  76 static int __init page_is_ram(unsigned long pagenr)
  77 {
  78         if (pagenr >= min_low_pfn && pagenr < max_low_pfn)
  79                 return 1;
  80         else
  81                 return 0;
  82 }
  83
  84 void __init paging_init(void)
  85 {
  86         unsigned long max_zone_pfns[MAX_NR_ZONES];
  87         unsigned long lastpfn;
  88
  89         pagetable_init();
  90         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
  91         lastpfn = max_low_pfn;
  92         free_area_init_nodes(max_zone_pfns);
  93 }
  94
  95 void __init mem_init(void)
  96 {
  97         unsigned long codesize, reservedpages, datasize, initsize;
  98         unsigned long tmp, ram = 0;
  99
 100         max_mapnr = max_low_pfn;
 101         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 102         totalram_pages += free_all_bootmem();
 103         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages. */
 104         reservedpages = 0;
 105
 106         for (tmp = 0; tmp < max_low_pfn; tmp++)
 107                 if (page_is_ram(tmp)) {
 108                         ram++;
 109                         if (PageReserved(pfn_to_page(tmp)))
 110                                 reservedpages++;
 111                 }
 112
 113         num_physpages = ram;
 114         codesize = (unsigned long) &_etext - (unsigned long) &_text;
 115         datasize = (unsigned long) &_edata - (unsigned long) &_etext;
 116         initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
 117
 118         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 119         kclist_add(&kcore_vmalloc, (void *) VMALLOC_START,
 120                         VMALLOC_END - VMALLOC_START);
 121
 122         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 123                         "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 124                         (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 125                         ram << (PAGE_SHIFT-10), codesize >> 10,
 126                         reservedpages << (PAGE_SHIFT-10), datasize >> 10,
 127                         initsize >> 10,
 128                         (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 129 }
 130 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 131
 132 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
 133 {
 134         unsigned long pfn;
 135
 136         for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
 137                 struct page *page = pfn_to_page(pfn);
 138                 void *addr = phys_to_virt(PFN_PHYS(pfn));
 139
 140                 ClearPageReserved(page);
 141                 init_page_count(page);
 142                 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
 143                 __free_page(page);
 144                 totalram_pages++;
 145         }
 146         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 147 }
 148
 149 #ifdef CONFIG_BLK_DEV_INITRD
 150 void free_initrd_mem(unsigned long start, unsigned long end)
 151 {
 152         free_init_pages("initrd memory",
 153         virt_to_phys((void *) start),
 154         virt_to_phys((void *) end));
 155 }
 156 #endif
 157
 158 void __init_refok free_initmem(void)
 159 {
 160         free_init_pages("unused kernel memory",
 161             (unsigned long)__init_begin, (unsigned long)__init_end);
 162 }
 163
 164 unsigned long pgd_current;
 165
 166 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
 167
 168 /*
 169  * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
 170  * are constants.  So we use the variants from asm-offset.h until that gcc
 171  * will officially be retired.
 172  */
 173 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);