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/string.h>
  26
  27 #include <asm/bootinfo.h>
  28 #include <asm/page.h>
  29
  30 #include <asm/mips-boards/prom.h>
  31
  32 /*#define DEBUG*/
  33
  34 enum yamon_memtypes {
  35         yamon_dontuse,
  36         yamon_prom,
  37         yamon_free,
  38 };
  39 struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];
  40
  41 #ifdef DEBUG
  42 static char *mtypes[3] = {
  43         "Dont use memory",
  44         "YAMON PROM memory",
  45         "Free memmory",
  46 };
  47 #endif
  48
  49 /* References to section boundaries */
  50 extern char _end;
  51
  52 #define PFN_ALIGN(x)    (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
  53
  54
  55 struct prom_pmemblock * __init prom_getmdesc(void)
  56 {
  57         char *memsize_str;
  58         unsigned int memsize;
  59         char cmdline[CL_SIZE], *ptr;
  60
  61         /* Check the command line first for a memsize directive */
  62         strcpy(cmdline, arcs_cmdline);
  63         ptr = strstr(cmdline, "memsize=");
  64         if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
  65                 ptr = strstr(ptr, " memsize=");
  66
  67         if (ptr) {
  68                 memsize = memparse(ptr + 8, &ptr);
  69         }
  70         else {
  71                 /* otherwise look in the environment */
  72                 memsize_str = prom_getenv("memsize");
  73                 if (!memsize_str) {
  74                         prom_printf("memsize not set in boot prom, set to default (32Mb)\n");
  75                         memsize = 0x02000000;
  76                 } else {
  77 #ifdef DEBUG
  78                         prom_printf("prom_memsize = %s\n", memsize_str);
  79 #endif
  80                         memsize = simple_strtol(memsize_str, NULL, 0);
  81                 }
  82         }
  83         memset(mdesc, 0, sizeof(mdesc));
  84
  85         mdesc[0].type = yamon_dontuse;
  86         mdesc[0].base = 0x00000000;
  87         mdesc[0].size = 0x00001000;
  88
  89         mdesc[1].type = yamon_prom;
  90         mdesc[1].base = 0x00001000;
  91         mdesc[1].size = 0x000ef000;
  92
  93 #ifdef CONFIG_MIPS_MALTA
  94         /*
  95          * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
  96          * south bridge and PCI access always forwarded to the ISA Bus and
  97          * BIOSCS# is always generated.
  98          * This mean that this area can't be used as DMA memory for PCI
  99          * devices.
 100          */
 101         mdesc[2].type = yamon_dontuse;
 102         mdesc[2].base = 0x000f0000;
 103         mdesc[2].size = 0x00010000;
 104 #else
 105         mdesc[2].type = yamon_prom;
 106         mdesc[2].base = 0x000f0000;
 107         mdesc[2].size = 0x00010000;
 108 #endif
 109
 110         mdesc[3].type = yamon_dontuse;
 111         mdesc[3].base = 0x00100000;
 112         mdesc[3].size = CPHYSADDR(PFN_ALIGN(&_end)) - mdesc[3].base;
 113
 114         mdesc[4].type = yamon_free;
 115         mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
 116         mdesc[4].size = memsize - mdesc[4].base;
 117
 118         return &mdesc[0];
 119 }
 120
 121 static int __init prom_memtype_classify (unsigned int type)
 122 {
 123         switch (type) {
 124         case yamon_free:
 125                 return BOOT_MEM_RAM;
 126         case yamon_prom:
 127                 return BOOT_MEM_ROM_DATA;
 128         default:
 129                 return BOOT_MEM_RESERVED;
 130         }
 131 }
 132
 133 void __init prom_meminit(void)
 134 {
 135         struct prom_pmemblock *p;
 136
 137 #ifdef DEBUG
 138         prom_printf("YAMON MEMORY DESCRIPTOR dump:\n");
 139         p = prom_getmdesc();
 140         while (p->size) {
 141                 int i = 0;
 142                 prom_printf("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
 143                             i, p, p->base, p->size, mtypes[p->type]);
 144                 p++;
 145                 i++;
 146         }
 147 #endif
 148         p = prom_getmdesc();
 149
 150         while (p->size) {
 151                 long type;
 152                 unsigned long base, size;
 153
 154                 type = prom_memtype_classify (p->type);
 155                 base = p->base;
 156                 size = p->size;
 157
 158                 add_memory_region(base, size, type);
 159                 p++;
 160         }
 161 }
 162
 163 unsigned long __init prom_free_prom_memory(void)
 164 {
 165         unsigned long freed = 0;
 166         unsigned long addr;
 167         int i;
 168
 169         for (i = 0; i < boot_mem_map.nr_map; i++) {
 170                 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
 171                         continue;
 172
 173                 addr = boot_mem_map.map[i].addr;
 174                 while (addr < boot_mem_map.map[i].addr
 175                               + boot_mem_map.map[i].size) {
 176                         ClearPageReserved(virt_to_page(__va(addr)));
 177                         set_page_count(virt_to_page(__va(addr)), 1);
 178                         free_page((unsigned long)__va(addr));
 179                         addr += PAGE_SIZE;
 180                         freed += PAGE_SIZE;
 181                 }
 182         }
 183         printk("Freeing prom memory: %ldkb freed\n", freed >> 10);
 184
 185         return freed;
 186 }