arch/blackfin/mm/init.c

   1 /*
   2  * File:         arch/blackfin/mm/init.c
   3  * Based on:
   4  * Author:
   5  *
   6  * Created:
   7  * Description:
   8  *
   9  * Modified:
  10  *               Copyright 2004-2006 Analog Devices Inc.
  11  *
  12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, see the file COPYING, or write
  26  * to the Free Software Foundation, Inc.,
  27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  28  */
  29
  30 #include <linux/swap.h>
  31 #include <linux/bootmem.h>
  32 #include <asm/bfin-global.h>
  33 #include <asm/uaccess.h>
  34 #include <asm/l1layout.h>
  35 #include "blackfin_sram.h"
  36
  37 /*
  38  * BAD_PAGE is the page that is used for page faults when linux
  39  * is out-of-memory. Older versions of linux just did a
  40  * do_exit(), but using this instead means there is less risk
  41  * for a process dying in kernel mode, possibly leaving a inode
  42  * unused etc..
  43  *
  44  * BAD_PAGETABLE is the accompanying page-table: it is initialized
  45  * to point to BAD_PAGE entries.
  46  *
  47  * ZERO_PAGE is a special page that is used for zero-initialized
  48  * data and COW.
  49  */
  50 static unsigned long empty_bad_page_table;
  51
  52 static unsigned long empty_bad_page;
  53
  54 unsigned long empty_zero_page;
  55
  56 void show_mem(void)
  57 {
  58         unsigned long i;
  59         int free = 0, total = 0, reserved = 0, shared = 0;
  60
  61         int cached = 0;
  62         printk(KERN_INFO "Mem-info:\n");
  63         show_free_areas();
  64         i = max_mapnr;
  65         while (i-- > 0) {
  66                 total++;
  67                 if (PageReserved(mem_map + i))
  68                         reserved++;
  69                 else if (PageSwapCache(mem_map + i))
  70                         cached++;
  71                 else if (!page_count(mem_map + i))
  72                         free++;
  73                 else
  74                         shared += page_count(mem_map + i) - 1;
  75         }
  76         printk(KERN_INFO "%d pages of RAM\n", total);
  77         printk(KERN_INFO "%d free pages\n", free);
  78         printk(KERN_INFO "%d reserved pages\n", reserved);
  79         printk(KERN_INFO "%d pages shared\n", shared);
  80         printk(KERN_INFO "%d pages swap cached\n", cached);
  81 }
  82
  83 /*
  84  * paging_init() continues the virtual memory environment setup which
  85  * was begun by the code in arch/head.S.
  86  * The parameters are pointers to where to stick the starting and ending
  87  * addresses  of available kernel virtual memory.
  88  */
  89 void paging_init(void)
  90 {
  91         /*
  92          * make sure start_mem is page aligned,  otherwise bootmem and
  93          * page_alloc get different views og the world
  94          */
  95         unsigned long end_mem = memory_end & PAGE_MASK;
  96
  97         pr_debug("start_mem is %#lx   virtual_end is %#lx\n", PAGE_ALIGN(memory_start), end_mem);
  98
  99         /*
 100          * initialize the bad page table and bad page to point
 101          * to a couple of allocated pages
 102          */
 103         empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
 104         empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
 105         empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
 106         memset((void *)empty_zero_page, 0, PAGE_SIZE);
 107
 108         /*
 109          * Set up SFC/DFC registers (user data space)
 110          */
 111         set_fs(KERNEL_DS);
 112
 113         pr_debug("free_area_init -> start_mem is %#lx   virtual_end is %#lx\n",
 114                 PAGE_ALIGN(memory_start), end_mem);
 115
 116         {
 117                 unsigned long zones_size[MAX_NR_ZONES] = { 0, };
 118
 119                 zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
 120 #ifdef CONFIG_HIGHMEM
 121                 zones_size[ZONE_HIGHMEM] = 0;
 122 #endif
 123                 free_area_init(zones_size);
 124         }
 125 }
 126
 127 void mem_init(void)
 128 {
 129         unsigned int codek = 0, datak = 0, initk = 0;
 130         unsigned long tmp;
 131         unsigned int len = _ramend - _rambase;
 132         unsigned long start_mem = memory_start;
 133         unsigned long end_mem = memory_end;
 134
 135         end_mem &= PAGE_MASK;
 136         high_memory = (void *)end_mem;
 137
 138         start_mem = PAGE_ALIGN(start_mem);
 139         max_mapnr = num_physpages = MAP_NR(high_memory);
 140         printk(KERN_INFO "Physical pages: %lx\n", num_physpages);
 141
 142         /* This will put all memory onto the freelists. */
 143         totalram_pages = free_all_bootmem();
 144
 145         codek = (_etext - _stext) >> 10;
 146         datak = (__bss_stop - __bss_start) >> 10;
 147         initk = (__init_end - __init_begin) >> 10;
 148
 149         tmp = nr_free_pages() << PAGE_SHIFT;
 150         printk(KERN_INFO
 151              "Memory available: %luk/%uk RAM, (%uk init code, %uk kernel code, %uk data, %uk dma)\n",
 152              tmp >> 10, len >> 10, initk, codek, datak, DMA_UNCACHED_REGION >> 10);
 153
 154         /* Initialize the blackfin L1 Memory. */
 155         l1sram_init();
 156         l1_data_sram_init();
 157         l1_inst_sram_init();
 158
 159         /* Allocate this once; never free it.  We assume this gives us a
 160            pointer to the start of L1 scratchpad memory; panic if it
 161            doesn't.  */
 162         tmp = (unsigned long)l1sram_alloc(sizeof(struct l1_scratch_task_info));
 163         if (tmp != (unsigned long)L1_SCRATCH_TASK_INFO) {
 164                 printk(KERN_EMERG "mem_init(): Did not get the right address from l1sram_alloc: %08lx != %08lx\n",
 165                         tmp, (unsigned long)L1_SCRATCH_TASK_INFO);
 166                 panic("No L1, time to give up\n");
 167         }
 168 }
 169
 170 #ifdef CONFIG_BLK_DEV_INITRD
 171 void free_initrd_mem(unsigned long start, unsigned long end)
 172 {
 173         int pages = 0;
 174         for (; start < end; start += PAGE_SIZE) {
 175                 ClearPageReserved(virt_to_page(start));
 176                 init_page_count(virt_to_page(start));
 177                 free_page(start);
 178                 totalram_pages++;
 179                 pages++;
 180         }
 181         printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
 182 }
 183 #endif
 184
 185 void free_initmem(void)
 186 {
 187 #ifdef CONFIG_RAMKERNEL
 188         unsigned long addr;
 189 /*
 190  *      the following code should be cool even if these sections
 191  *      are not page aligned.
 192  */
 193         addr = PAGE_ALIGN((unsigned long)(__init_begin));
 194         /* next to check that the page we free is not a partial page */
 195         for (; addr + PAGE_SIZE < (unsigned long)(__init_end);
 196              addr += PAGE_SIZE) {
 197                 ClearPageReserved(virt_to_page(addr));
 198                 init_page_count(virt_to_page(addr));
 199                 free_page(addr);
 200                 totalram_pages++;
 201         }
 202         printk(KERN_NOTICE
 203                "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n",
 204                (addr - PAGE_ALIGN((long)__init_begin)) >> 10,
 205                (int)(PAGE_ALIGN((unsigned long)(__init_begin))),
 206                (int)(addr - PAGE_SIZE));
 207 #endif
 208 }