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 #include <asm/pgtable.h>
  23
  24 /* Don't add a printk in there. printk relies on the PDA which is not initialized
  25    yet. */
  26 static void __init clear_bss(void)
  27 {
  28         extern char __bss_start[], __bss_end[];
  29         memset(__bss_start, 0,
  30                (unsigned long) __bss_end - (unsigned long) __bss_start);
  31 }
  32
  33 #define NEW_CL_POINTER          0x228   /* Relative to real mode data */
  34 #define OLD_CL_MAGIC_ADDR       0x90020
  35 #define OLD_CL_MAGIC            0xA33F
  36 #define OLD_CL_BASE_ADDR        0x90000
  37 #define OLD_CL_OFFSET           0x90022
  38
  39 extern char saved_command_line[];
  40
  41 static void __init copy_bootdata(char *real_mode_data)
  42 {
  43         int new_data;
  44         char * command_line;
  45
  46         memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE);
  47         new_data = *(int *) (x86_boot_params + NEW_CL_POINTER);
  48         if (!new_data) {
  49                 if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) {
  50                         printk("so old bootloader that it does not support commandline?!\n");
  51                         return;
  52                 }
  53                 new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET;
  54                 printk("old bootloader convention, maybe loadlin?\n");
  55         }
  56         command_line = (char *) ((u64)(new_data));
  57         memcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
  58         printk("Bootdata ok (command line is %s)\n", saved_command_line);
  59 }
  60
  61 static void __init setup_boot_cpu_data(void)
  62 {
  63         unsigned int dummy, eax;
  64
  65         /* get vendor info */
  66         cpuid(0, (unsigned int *)&boot_cpu_data.cpuid_level,
  67               (unsigned int *)&boot_cpu_data.x86_vendor_id[0],
  68               (unsigned int *)&boot_cpu_data.x86_vendor_id[8],
  69               (unsigned int *)&boot_cpu_data.x86_vendor_id[4]);
  70
  71         /* get cpu type */
  72         cpuid(1, &eax, &dummy, &dummy,
  73                 (unsigned int *) &boot_cpu_data.x86_capability);
  74         boot_cpu_data.x86 = (eax >> 8) & 0xf;
  75         boot_cpu_data.x86_model = (eax >> 4) & 0xf;
  76         boot_cpu_data.x86_mask = eax & 0xf;
  77 }
  78
  79 extern char _end[];
  80
  81 void __init x86_64_start_kernel(char * real_mode_data)
  82 {
  83         char *s;
  84         int i;
  85
  86         for (i = 0; i < 256; i++)
  87                 set_intr_gate(i, early_idt_handler);
  88         asm volatile("lidt %0" :: "m" (idt_descr));
  89         clear_bss();
  90
  91         /*
  92          * switch to init_level4_pgt from boot_level4_pgt
  93          */
  94         memcpy(init_level4_pgt, boot_level4_pgt, PTRS_PER_PGD*sizeof(pgd_t));
  95         asm volatile("movq %0,%%cr3" :: "r" (__pa_symbol(&init_level4_pgt)));
  96
  97         pda_init(0);
  98         copy_bootdata(real_mode_data);
  99 #ifdef CONFIG_SMP
 100         cpu_set(0, cpu_online_map);
 101 #endif
 102         s = strstr(saved_command_line, "earlyprintk=");
 103         if (s != NULL)
 104                 setup_early_printk(s);
 105 #ifdef CONFIG_NUMA
 106         s = strstr(saved_command_line, "numa=");
 107         if (s != NULL)
 108                 numa_setup(s+5);
 109 #endif
 110 #ifdef CONFIG_X86_IO_APIC
 111         if (strstr(saved_command_line, "disableapic"))
 112                 disable_apic = 1;
 113 #endif
 114         /* You need early console to see that */
 115         if (__pa_symbol(&_end) >= KERNEL_TEXT_SIZE)
 116                 panic("Kernel too big for kernel mapping\n");
 117
 118         setup_boot_cpu_data();
 119         start_kernel();
 120 }