arch/mips/powertv/init.c

   1 /*
   2  * Copyright (C) 1999, 2000, 2004, 2005  MIPS Technologies, Inc.
   3  *      All rights reserved.
   4  *      Authors: Carsten Langgaard <carstenl@mips.com>
   5  *               Maciej W. Rozycki <macro@mips.com>
   6  * Portions copyright (C) 2009 Cisco Systems, Inc.
   7  *
   8  *  This program is free software; you can distribute it and/or modify it
   9  *  under the terms of the GNU General Public License (Version 2) as
  10  *  published by the Free Software Foundation.
  11  *
  12  *  This program is distributed in the hope it will be useful, but WITHOUT
  13  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  *  for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License along
  18  *  with this program; if not, write to the Free Software Foundation, Inc.,
  19  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  20  *
  21  * PROM library initialisation code.
  22  */
  23 #include <linux/init.h>
  24 #include <linux/string.h>
  25 #include <linux/kernel.h>
  26
  27 #include <asm/bootinfo.h>
  28 #include <linux/io.h>
  29 #include <asm/cacheflush.h>
  30 #include <asm/traps.h>
  31
  32 #include <asm/mips-boards/generic.h>
  33 #include <asm/mach-powertv/asic.h>
  34
  35 #include "init.h"
  36
  37 static int *_prom_envp;
  38 unsigned long _prom_memsize;
  39
  40 /*
  41  * YAMON (32-bit PROM) pass arguments and environment as 32-bit pointer.
  42  * This macro take care of sign extension, if running in 64-bit mode.
  43  */
  44 #define prom_envp(index) ((char *)(long)_prom_envp[(index)])
  45
  46 char *prom_getenv(char *envname)
  47 {
  48         char *result = NULL;
  49
  50         if (_prom_envp != NULL) {
  51                 /*
  52                  * Return a pointer to the given environment variable.
  53                  * In 64-bit mode: we're using 64-bit pointers, but all pointers
  54                  * in the PROM structures are only 32-bit, so we need some
  55                  * workarounds, if we are running in 64-bit mode.
  56                  */
  57                 int i, index = 0;
  58
  59                 i = strlen(envname);
  60
  61                 while (prom_envp(index)) {
  62                         if (strncmp(envname, prom_envp(index), i) == 0) {
  63                                 result = prom_envp(index + 1);
  64                                 break;
  65                         }
  66                         index += 2;
  67                 }
  68         }
  69
  70         return result;
  71 }
  72
  73 void __init prom_init(void)
  74 {
  75         int prom_argc;
  76         char *prom_argv;
  77
  78         prom_argc = fw_arg0;
  79         prom_argv = (char *) fw_arg1;
  80         _prom_envp = (int *) fw_arg2;
  81         _prom_memsize = (unsigned long) fw_arg3;
  82
  83         if (prom_argc == 1) {
  84                 strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
  85                 strlcat(arcs_cmdline, prom_argv, COMMAND_LINE_SIZE);
  86         }
  87
  88         configure_platform();
  89         prom_meminit();
  90
  91 #ifndef CONFIG_BOOTLOADER_DRIVER
  92         pr_info("\nBootloader driver isn't loaded...\n");
  93 #endif
  94 }