root/arch/mips/kernel/setup.c

/* */

DEFINITIONS

1. setup_arch

   1 /*
   2  *  linux/arch/mips/kernel/setup.c
   3  *
   4  *  Copyright (C) 1995  Linus Torvalds
   5  */
   6 
   7 #include <linux/errno.h>
   8 #include <linux/sched.h>
   9 #include <linux/kernel.h>
  10 #include <linux/mm.h>
  11 #include <linux/stddef.h>
  12 #include <linux/unistd.h>
  13 #include <linux/ptrace.h>
  14 #include <linux/malloc.h>
  15 #include <linux/ldt.h>
  16 #include <linux/user.h>
  17 #include <linux/a.out.h>
  18 #include <linux/tty.h>
  19 
  20 #include <asm/bootinfo.h>
  21 #include <asm/segment.h>
  22 #include <asm/system.h>
  23 
  24 /*
  25  * Tell us the machine setup..
  26  */
  27 char wait_available;            /* set if the "wait" instruction available */
  28 
  29 /*
  30  * Bus types ..
  31  */
  32 int EISA_bus = 0;
  33 
  34 /*
  35  * Setup options
  36  */
  37 struct drive_info_struct drive_info;
  38 struct screen_info screen_info;
  39 
  40 unsigned char aux_device_present;
  41 extern int ramdisk_size;
  42 extern int root_mountflags;
  43 extern int end;
  44 
  45 extern char empty_zero_page[PAGE_SIZE];
  46 
  47 /*
  48  * Initialise this structure so that it will be placed in the
  49  * .data section of the object file
  50  */
  51 struct bootinfo boot_info = BOOT_INFO;
  52 
  53 /*
  54  * This is set up by the setup-routine at boot-time
  55  */
  56 #define PARAM   empty_zero_page
  57 #define EXT_MEM (boot_info.memupper)
  58 #define DRIVE_INFO (boot_info.drive_info)
  59 #define SCREEN_INFO (screen_info)
  60 #define MOUNT_ROOT_RDONLY (boot_info.mount_root_rdonly)
  61 #define RAMDISK_SIZE (boot_info.ramdisk_size)
  62 #if 0
  63 #define ORIG_ROOT_DEV (*(unsigned short *) (PARAM+0x1FC))
  64 #define AUX_DEVICE_INFO (*(unsigned char *) (PARAM+0x1FF))
  65 #endif
  66 #define COMMAND_LINE (boot_info.command_line)
  67 
  68 static char command_line[CL_SIZE] = { 0, };
  69 
  70 void setup_arch(char **cmdline_p,
     /*  */
  71         unsigned long * memory_start_p, unsigned long * memory_end_p)
  72 {
  73         unsigned long memory_start, memory_end;
  74         char c = ' ', *to = command_line, *from = COMMAND_LINE;
  75         int len = 0;
  76 
  77 #if 0
  78         ROOT_DEV = ORIG_ROOT_DEV;
  79 #endif
  80         drive_info = DRIVE_INFO;
  81         screen_info = SCREEN_INFO;
  82 #if 0
  83         aux_device_present = AUX_DEVICE_INFO;
  84 #endif
  85         memory_end = EXT_MEM;
  86         memory_end &= PAGE_MASK;
  87         ramdisk_size = RAMDISK_SIZE;
  88         if (MOUNT_ROOT_RDONLY)
  89                 root_mountflags |= MS_RDONLY;
  90         memory_start = (unsigned long) &end - KERNELBASE;
  91 
  92         for (;;) {
  93                 if (c == ' ' && *(unsigned long *)from == *(unsigned long *)"mem=") {
  94                         memory_end = simple_strtoul(from+4, &from, 0);
  95                         if ( *from == 'K' || *from == 'k' ) {
  96                                 memory_end = memory_end << 10;
  97                                 from++;
  98                         } else if ( *from == 'M' || *from == 'm' ) {
  99                                 memory_end = memory_end << 20;
 100                                 from++;
 101                         }
 102                 }
 103                 c = *(from++);
 104                 if (!c)
 105                         break;
 106                 if (CL_SIZE <= ++len)
 107                         break;
 108                 *(to++) = c;
 109         }
 110         *to = '\0';
 111         *cmdline_p = command_line;
 112         *memory_start_p = memory_start;
 113         *memory_end_p = memory_end;
 114 }

/* */