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 #include <linux/pfn.h>
  26 #include <linux/string.h>
  27
  28 #include <asm/bootinfo.h>
  29 #include <asm/page.h>
  30 #include <asm/sections.h>
  31
  32 #include <asm/mips-boards/prom.h>
  33
  34 /*#define DEBUG*/
  35
  36 enum yamon_memtypes {
  37         yamon_dontuse,
  38         yamon_prom,
  39         yamon_free,
  40 };
  41 struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];
  42
  43 #ifdef DEBUG
  44 static char *mtypes[3] = {
  45         "Dont use memory",
  46         "YAMON PROM memory",
  47         "Free memmory",
  48 };
  49 #endif
  50
  51 struct prom_pmemblock * __init prom_getmdesc(void)
  52 {
  53         char *memsize_str;
  54         unsigned int memsize;
  55         char cmdline[CL_SIZE], *ptr;
  56
  57         /* Check the command line first for a memsize directive */
  58         strcpy(cmdline, arcs_cmdline);
  59         ptr = strstr(cmdline, "memsize=");
  60         if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
  61                 ptr = strstr(ptr, " memsize=");
  62
  63         if (ptr) {
  64                 memsize = memparse(ptr + 8, &ptr);
  65         }
  66         else {
  67                 /* otherwise look in the environment */
  68                 memsize_str = prom_getenv("memsize");
  69                 if (!memsize_str) {
  70                         prom_printf("memsize not set in boot prom, set to default (32Mb)\n");
  71                         memsize = 0x02000000;
  72                 } else {
  73 #ifdef DEBUG
  74                         prom_printf("prom_memsize = %s\n", memsize_str);
  75 #endif
  76                         memsize = simple_strtol(memsize_str, NULL, 0);
  77                 }
  78         }
  79         memset(mdesc, 0, sizeof(mdesc));
  80
  81         mdesc[0].type = yamon_dontuse;
  82         mdesc[0].base = 0x00000000;
  83         mdesc[0].size = 0x00001000;
  84
  85         mdesc[1].type = yamon_prom;
  86         mdesc[1].base = 0x00001000;
  87         mdesc[1].size = 0x000ef000;
  88
  89 #ifdef CONFIG_MIPS_MALTA
  90         /*
  91          * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
  92          * south bridge and PCI access always forwarded to the ISA Bus and
  93          * BIOSCS# is always generated.
  94          * This mean that this area can't be used as DMA memory for PCI
  95          * devices.
  96          */
  97         mdesc[2].type = yamon_dontuse;
  98         mdesc[2].base = 0x000f0000;
  99         mdesc[2].size = 0x00010000;
 100 #else
 101         mdesc[2].type = yamon_prom;
 102         mdesc[2].base = 0x000f0000;
 103         mdesc[2].size = 0x00010000;
 104 #endif
 105
 106         mdesc[3].type = yamon_dontuse;
 107         mdesc[3].base = 0x00100000;
 108         mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) - mdesc[3].base;
 109
 110         mdesc[4].type = yamon_free;
 111         mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
 112         mdesc[4].size = memsize - mdesc[4].base;
 113
 114         return &mdesc[0];
 115 }
 116
 117 static int __init prom_memtype_classify (unsigned int type)
 118 {
 119         switch (type) {
 120         case yamon_free:
 121                 return BOOT_MEM_RAM;
 122         case yamon_prom:
 123                 return BOOT_MEM_ROM_DATA;
 124         default:
 125                 return BOOT_MEM_RESERVED;
 126         }
 127 }
 128
 129 void __init prom_meminit(void)
 130 {
 131         struct prom_pmemblock *p;
 132
 133 #ifdef DEBUG
 134         prom_printf("YAMON MEMORY DESCRIPTOR dump:\n");
 135         p = prom_getmdesc();
 136         while (p->size) {
 137                 int i = 0;
 138                 prom_printf("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
 139                             i, p, p->base, p->size, mtypes[p->type]);
 140                 p++;
 141                 i++;
 142         }
 143 #endif
 144         p = prom_getmdesc();
 145
 146         while (p->size) {
 147                 long type;
 148                 unsigned long base, size;
 149
 150                 type = prom_memtype_classify (p->type);
 151                 base = p->base;
 152                 size = p->size;
 153
 154                 add_memory_region(base, size, type);
 155                 p++;
 156         }
 157 }
 158
 159 unsigned long __init prom_free_prom_memory(void)
 160 {
 161         unsigned long freed = 0;
 162         unsigned long addr;
 163         int i;
 164
 165         for (i = 0; i < boot_mem_map.nr_map; i++) {
 166                 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
 167                         continue;
 168
 169                 addr = boot_mem_map.map[i].addr;
 170                 while (addr < boot_mem_map.map[i].addr
 171                               + boot_mem_map.map[i].size) {
 172                         ClearPageReserved(virt_to_page(__va(addr)));
 173                         init_page_count(virt_to_page(__va(addr)));
 174                         free_page((unsigned long)__va(addr));
 175                         addr += PAGE_SIZE;
 176                         freed += PAGE_SIZE;
 177                 }
 178         }
 179         printk("Freeing prom memory: %ldkb freed\n", freed >> 10);
 180
 181         return freed;
 182 }