arch/x86_64/kernel/head64.c

   1 /*
   2  *  linux/arch/x86_64/kernel/head64.c -- prepare to run common code
   3  *
   4  *  Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
   5  *
   6  *  $Id: head64.c,v 1.22 2001/07/06 14:28:20 ak Exp $
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/linkage.h>
  11 #include <linux/types.h>
  12 #include <linux/kernel.h>
  13 #include <linux/string.h>
  14 #include <linux/percpu.h>
  15
  16 #include <asm/processor.h>
  17 #include <asm/proto.h>
  18 #include <asm/smp.h>
  19 #include <asm/bootsetup.h>
  20 #include <asm/setup.h>
  21 #include <asm/desc.h>
  22
  23 /* Don't add a printk in there. printk relies on the PDA which is not initialized
  24    yet. */
  25 static void __init clear_bss(void)
  26 {
  27         extern char __bss_start[], __bss_end[];
  28         memset(__bss_start, 0,
  29                (unsigned long) __bss_end - (unsigned long) __bss_start);
  30 }
  31
  32 extern char x86_boot_params[2048];
  33
  34 #define NEW_CL_POINTER          0x228   /* Relative to real mode data */
  35 #define OLD_CL_MAGIC_ADDR       0x90020
  36 #define OLD_CL_MAGIC            0xA33F
  37 #define OLD_CL_BASE_ADDR        0x90000
  38 #define OLD_CL_OFFSET           0x90022
  39
  40 extern char saved_command_line[];
  41
  42 static void __init copy_bootdata(char *real_mode_data)
  43 {
  44         int new_data;
  45         char * command_line;
  46
  47         memcpy(x86_boot_params, real_mode_data, 2048);
  48         new_data = *(int *) (x86_boot_params + NEW_CL_POINTER);
  49         if (!new_data) {
  50                 if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) {
  51                         printk("so old bootloader that it does not support commandline?!\n");
  52                         return;
  53                 }
  54                 new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET;
  55                 printk("old bootloader convention, maybe loadlin?\n");
  56         }
  57         command_line = (char *) ((u64)(new_data));
  58         memcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
  59         printk("Bootdata ok (command line is %s)\n", saved_command_line);
  60 }
  61
  62 static void __init setup_boot_cpu_data(void)
  63 {
  64         unsigned int dummy, eax;
  65
  66         /* get vendor info */
  67         cpuid(0, (unsigned int *)&boot_cpu_data.cpuid_level,
  68               (unsigned int *)&boot_cpu_data.x86_vendor_id[0],
  69               (unsigned int *)&boot_cpu_data.x86_vendor_id[8],
  70               (unsigned int *)&boot_cpu_data.x86_vendor_id[4]);
  71
  72         /* get cpu type */
  73         cpuid(1, &eax, &dummy, &dummy,
  74                 (unsigned int *) &boot_cpu_data.x86_capability);
  75         boot_cpu_data.x86 = (eax >> 8) & 0xf;
  76         boot_cpu_data.x86_model = (eax >> 4) & 0xf;
  77         boot_cpu_data.x86_mask = eax & 0xf;
  78 }
  79
  80 extern char _end[];
  81
  82 void __init x86_64_start_kernel(char * real_mode_data)
  83 {
  84         char *s;
  85         int i;
  86
  87         for (i = 0; i < 256; i++)
  88                 set_intr_gate(i, early_idt_handler);
  89         asm volatile("lidt %0" :: "m" (idt_descr));
  90         clear_bss();
  91         pda_init(0);
  92         copy_bootdata(real_mode_data);
  93 #ifdef CONFIG_SMP
  94         cpu_set(0, cpu_online_map);
  95 #endif
  96         /* default console: */
  97         if (!strstr(saved_command_line, "console="))
  98                 strcat(saved_command_line, " console=tty0");
  99         s = strstr(saved_command_line, "earlyprintk=");
 100         if (s != NULL)
 101                 setup_early_printk(s);
 102 #ifdef CONFIG_DISCONTIGMEM
 103         s = strstr(saved_command_line, "numa=");
 104         if (s != NULL)
 105                 numa_setup(s+5);
 106 #endif
 107 #ifdef CONFIG_X86_IO_APIC
 108         if (strstr(saved_command_line, "disableapic"))
 109                 disable_apic = 1;
 110 #endif
 111         /* You need early console to see that */
 112         if (__pa_symbol(&_end) >= KERNEL_TEXT_SIZE)
 113                 panic("Kernel too big for kernel mapping\n");
 114
 115         setup_boot_cpu_data();
 116         start_kernel();
 117 }