target/linux/ar7/files/arch/mips/ar7/memory.c

   1 /*
   2  * Based on arch/mips/mm/init.c
   3  * Copyright (C) 1994 - 2000 Ralf Baechle
   4  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   5  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
   6  * Copyright (C) 2000 MIPS Technologies, Inc.  All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  */
  22 #include <linux/bootmem.h>
  23 #include <linux/init.h>
  24 #include <linux/mm.h>
  25 #include <linux/module.h>
  26 #include <linux/pfn.h>
  27 #include <linux/proc_fs.h>
  28 #include <linux/string.h>
  29 #include <linux/swap.h>
  30
  31 #include <asm/bootinfo.h>
  32 #include <asm/page.h>
  33 #include <asm/sections.h>
  34
  35 #include <asm/mips-boards/prom.h>
  36
  37 static int __init memsize(void)
  38 {
  39         u32 size = (64 << 20);
  40         u32 *addr = (u32 *)KSEG1ADDR(0x14000000 + size - 4);
  41         u32 *kernel_end = (u32 *)KSEG1ADDR(CPHYSADDR((u32)&_end));
  42         u32 *tmpaddr = addr;
  43
  44         while (tmpaddr > kernel_end) {
  45                 *tmpaddr = (u32)tmpaddr;
  46                 size >>= 1;
  47                 tmpaddr -= size >> 2;
  48         }
  49
  50         do {
  51                 tmpaddr += size >> 2;
  52                 if (*tmpaddr != (u32)tmpaddr)
  53                         break;
  54                 size <<= 1;
  55         } while (size < (64 << 20));
  56
  57         writel(tmpaddr, &addr);
  58
  59         return size;
  60 }
  61
  62 void __init prom_meminit(void)
  63 {
  64         unsigned long pages;
  65
  66         pages = memsize() >> PAGE_SHIFT;
  67         add_memory_region(PHYS_OFFSET, pages << PAGE_SHIFT,
  68                           BOOT_MEM_RAM);
  69 }
  70
  71 void __init prom_free_prom_memory(void)
  72 {
  73         return;
  74 }