arch/mips/mips-boards/generic/memory.c

   1 /*
   2  * Carsten Langgaard, carstenl@mips.com
   3  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
   4  *
   5  *  This program is free software; you can distribute it and/or modify it
   6  *  under the terms of the GNU General Public License (Version 2) as
   7  *  published by the Free Software Foundation.
   8  *
   9  *  This program is distributed in the hope it will be useful, but WITHOUT
  10  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  *  for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License along
  15  *  with this program; if not, write to the Free Software Foundation, Inc.,
  16  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  17  *
  18  * PROM library functions for acquiring/using memory descriptors given to
  19  * us from the YAMON.
  20  */
  21 #include <linux/config.h>
  22 #include <linux/init.h>
  23 #include <linux/mm.h>
  24 #include <linux/bootmem.h>
  25
  26 #include <asm/bootinfo.h>
  27 #include <asm/page.h>
  28
  29 #include <asm/mips-boards/prom.h>
  30
  31 /*#define DEBUG*/
  32
  33 enum yamon_memtypes {
  34         yamon_dontuse,
  35         yamon_prom,
  36         yamon_free,
  37 };
  38 struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];
  39
  40 #ifdef DEBUG
  41 static char *mtypes[3] = {
  42         "Dont use memory",
  43         "YAMON PROM memory",
  44         "Free memmory",
  45 };
  46 #endif
  47
  48 /* References to section boundaries */
  49 extern char _end;
  50
  51 #define PFN_ALIGN(x)    (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
  52
  53
  54 struct prom_pmemblock * __init prom_getmdesc(void)
  55 {
  56         char *memsize_str;
  57         unsigned int memsize;
  58
  59         memsize_str = prom_getenv("memsize");
  60         if (!memsize_str) {
  61                 prom_printf("memsize not set in boot prom, set to default (32Mb)\n");
  62                 memsize = 0x02000000;
  63         } else {
  64 #ifdef DEBUG
  65                 prom_printf("prom_memsize = %s\n", memsize_str);
  66 #endif
  67                 memsize = simple_strtol(memsize_str, NULL, 0);
  68         }
  69
  70         memset(mdesc, 0, sizeof(mdesc));
  71
  72         mdesc[0].type = yamon_dontuse;
  73         mdesc[0].base = 0x00000000;
  74         mdesc[0].size = 0x00001000;
  75
  76         mdesc[1].type = yamon_prom;
  77         mdesc[1].base = 0x00001000;
  78         mdesc[1].size = 0x000ef000;
  79
  80 #ifdef CONFIG_MIPS_MALTA
  81         /*
  82          * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
  83          * south bridge and PCI access always forwarded to the ISA Bus and
  84          * BIOSCS# is always generated.
  85          * This mean that this area can't be used as DMA memory for PCI
  86          * devices.
  87          */
  88         mdesc[2].type = yamon_dontuse;
  89         mdesc[2].base = 0x000f0000;
  90         mdesc[2].size = 0x00010000;
  91 #else
  92         mdesc[2].type = yamon_prom;
  93         mdesc[2].base = 0x000f0000;
  94         mdesc[2].size = 0x00010000;
  95 #endif
  96
  97         mdesc[3].type = yamon_dontuse;
  98         mdesc[3].base = 0x00100000;
  99         mdesc[3].size = CPHYSADDR(PFN_ALIGN(&_end)) - mdesc[3].base;
 100
 101         mdesc[4].type = yamon_free;
 102         mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
 103         mdesc[4].size = memsize - mdesc[4].base;
 104
 105         return &mdesc[0];
 106 }
 107
 108 static int __init prom_memtype_classify (unsigned int type)
 109 {
 110         switch (type) {
 111         case yamon_free:
 112                 return BOOT_MEM_RAM;
 113         case yamon_prom:
 114                 return BOOT_MEM_ROM_DATA;
 115         default:
 116                 return BOOT_MEM_RESERVED;
 117         }
 118 }
 119
 120 void __init prom_meminit(void)
 121 {
 122         struct prom_pmemblock *p;
 123
 124 #ifdef DEBUG
 125         prom_printf("YAMON MEMORY DESCRIPTOR dump:\n");
 126         p = prom_getmdesc();
 127         while (p->size) {
 128                 int i = 0;
 129                 prom_printf("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
 130                             i, p, p->base, p->size, mtypes[p->type]);
 131                 p++;
 132                 i++;
 133         }
 134 #endif
 135         p = prom_getmdesc();
 136
 137         while (p->size) {
 138                 long type;
 139                 unsigned long base, size;
 140
 141                 type = prom_memtype_classify (p->type);
 142                 base = p->base;
 143                 size = p->size;
 144
 145                 add_memory_region(base, size, type);
 146                 p++;
 147         }
 148 }
 149
 150 unsigned long __init prom_free_prom_memory(void)
 151 {
 152         unsigned long freed = 0;
 153         unsigned long addr;
 154         int i;
 155
 156         for (i = 0; i < boot_mem_map.nr_map; i++) {
 157                 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
 158                         continue;
 159
 160                 addr = boot_mem_map.map[i].addr;
 161                 while (addr < boot_mem_map.map[i].addr
 162                               + boot_mem_map.map[i].size) {
 163                         ClearPageReserved(virt_to_page(__va(addr)));
 164                         set_page_count(virt_to_page(__va(addr)), 1);
 165                         free_page((unsigned long)__va(addr));
 166                         addr += PAGE_SIZE;
 167                         freed += PAGE_SIZE;
 168                 }
 169         }
 170         printk("Freeing prom memory: %ldkb freed\n", freed >> 10);
 171
 172         return freed;
 173 }