arch/mips/powertv/memory.c

   1 /*
   2  * Carsten Langgaard, carstenl@mips.com
   3  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
   4  * Portions copyright (C) 2009 Cisco Systems, Inc.
   5  *
   6  *  This program is free software; you can distribute it and/or modify it
   7  *  under the terms of the GNU General Public License (Version 2) as
   8  *  published by the Free Software Foundation.
   9  *
  10  *  This program is distributed in the hope it will be useful, but WITHOUT
  11  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  *  for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License along
  16  *  with this program; if not, write to the Free Software Foundation, Inc.,
  17  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  18  *
  19  * Apparently originally from arch/mips/malta-memory.c. Modified to work
  20  * with the PowerTV bootloader.
  21  */
  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 #include "init.h"
  35
  36 /* Memory constants */
  37 #define KIBIBYTE(n)             ((n) * 1024)    /* Number of kibibytes */
  38 #define MEBIBYTE(n)             ((n) * KIBIBYTE(1024)) /* Number of mebibytes */
  39 #define DEFAULT_MEMSIZE         MEBIBYTE(256)   /* If no memsize provided */
  40 #define LOW_MEM_MAX             MEBIBYTE(252)   /* Max usable low mem */
  41 #define RES_BOOTLDR_MEMSIZE     MEBIBYTE(1)     /* Memory reserved for bldr */
  42 #define BOOT_MEM_SIZE           KIBIBYTE(256)   /* Memory reserved for bldr */
  43 #define PHYS_MEM_START          0x10000000      /* Start of physical memory */
  44
  45 char __initdata cmdline[COMMAND_LINE_SIZE];
  46
  47 void __init prom_meminit(void)
  48 {
  49         char *memsize_str;
  50         unsigned long memsize = 0;
  51         unsigned int physend;
  52         char *ptr;
  53         int low_mem;
  54         int high_mem;
  55
  56         /* Check the command line first for a memsize directive */
  57         strcpy(cmdline, arcs_cmdline);
  58         ptr = strstr(cmdline, "memsize=");
  59         if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
  60                 ptr = strstr(ptr, " memsize=");
  61
  62         if (ptr) {
  63                 memsize = memparse(ptr + 8, &ptr);
  64         } else {
  65                 /* otherwise look in the environment */
  66                 memsize_str = prom_getenv("memsize");
  67
  68                 if (memsize_str != NULL) {
  69                         pr_info("prom memsize = %s\n", memsize_str);
  70                         memsize = simple_strtol(memsize_str, NULL, 0);
  71                 }
  72
  73                 if (memsize == 0) {
  74                         if (_prom_memsize != 0) {
  75                                 memsize = _prom_memsize;
  76                                 pr_info("_prom_memsize = 0x%lx\n", memsize);
  77                                 /* add in memory that the bootloader doesn't
  78                                  * report */
  79                                 memsize += BOOT_MEM_SIZE;
  80                         } else {
  81                                 memsize = DEFAULT_MEMSIZE;
  82                                 pr_info("Memsize not passed by bootloader, "
  83                                         "defaulting to 0x%lx\n", memsize);
  84                         }
  85                 }
  86         }
  87
  88         physend = PFN_ALIGN(&_end) - 0x80000000;
  89         if (memsize > LOW_MEM_MAX) {
  90                 low_mem = LOW_MEM_MAX;
  91                 high_mem = memsize - low_mem;
  92         } else {
  93                 low_mem = memsize;
  94                 high_mem = 0;
  95         }
  96
  97 /*
  98  * TODO: We will use the hard code for memory configuration until
  99  * the bootloader releases their device tree to us.
 100  */
 101         /*
 102          * Add the memory reserved for use by the bootloader to the
 103          * memory map.
 104          */
 105         add_memory_region(PHYS_MEM_START, RES_BOOTLDR_MEMSIZE,
 106                 BOOT_MEM_RESERVED);
 107 #ifdef CONFIG_HIGHMEM_256_128
 108         /*
 109          * Add memory in low for general use by the kernel and its friends
 110          * (like drivers, applications, etc).
 111          */
 112         add_memory_region(PHYS_MEM_START + RES_BOOTLDR_MEMSIZE,
 113                 LOW_MEM_MAX - RES_BOOTLDR_MEMSIZE, BOOT_MEM_RAM);
 114         /*
 115          * Add the memory reserved for reset vector.
 116          */
 117         add_memory_region(0x1fc00000, MEBIBYTE(4), BOOT_MEM_RESERVED);
 118         /*
 119          * Add the memory reserved.
 120          */
 121         add_memory_region(0x20000000, MEBIBYTE(1024 + 75), BOOT_MEM_RESERVED);
 122         /*
 123          * Add memory in high for general use by the kernel and its friends
 124          * (like drivers, applications, etc).
 125          *
 126          * 75MB is reserved for devices which are using the memory in high.
 127          */
 128         add_memory_region(0x60000000 + MEBIBYTE(75), MEBIBYTE(128 - 75),
 129                 BOOT_MEM_RAM);
 130 #elif defined CONFIG_HIGHMEM_128_128
 131         /*
 132          * Add memory in low for general use by the kernel and its friends
 133          * (like drivers, applications, etc).
 134          */
 135         add_memory_region(PHYS_MEM_START + RES_BOOTLDR_MEMSIZE,
 136                 MEBIBYTE(128) - RES_BOOTLDR_MEMSIZE, BOOT_MEM_RAM);
 137         /*
 138          * Add the memory reserved.
 139          */
 140         add_memory_region(PHYS_MEM_START + MEBIBYTE(128),
 141                 MEBIBYTE(128 + 1024 + 75), BOOT_MEM_RESERVED);
 142         /*
 143          * Add memory in high for general use by the kernel and its friends
 144          * (like drivers, applications, etc).
 145          *
 146          * 75MB is reserved for devices which are using the memory in high.
 147          */
 148         add_memory_region(0x60000000 + MEBIBYTE(75), MEBIBYTE(128 - 75),
 149                 BOOT_MEM_RAM);
 150 #else
 151         /* Add low memory regions for either:
 152          *   - no-highmemory configuration case -OR-
 153          *   - highmemory "HIGHMEM_LOWBANK_ONLY" case
 154          */
 155         /*
 156          * Add memory for general use by the kernel and its friends
 157          * (like drivers, applications, etc).
 158          */
 159         add_memory_region(PHYS_MEM_START + RES_BOOTLDR_MEMSIZE,
 160                 low_mem - RES_BOOTLDR_MEMSIZE, BOOT_MEM_RAM);
 161         /*
 162          * Add the memory reserved for reset vector.
 163          */
 164         add_memory_region(0x1fc00000, MEBIBYTE(4), BOOT_MEM_RESERVED);
 165 #endif
 166 }
 167
 168 void __init prom_free_prom_memory(void)
 169 {
 170         unsigned long addr;
 171         int i;
 172
 173         for (i = 0; i < boot_mem_map.nr_map; i++) {
 174                 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
 175                         continue;
 176
 177                 addr = boot_mem_map.map[i].addr;
 178                 free_init_pages("prom memory",
 179                                 addr, addr + boot_mem_map.map[i].size);
 180         }
 181 }