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
   7 #include <linux/init.h>
   8 #include <linux/linkage.h>
   9 #include <linux/types.h>
  10 #include <linux/kernel.h>
  11 #include <linux/string.h>
  12 #include <linux/percpu.h>
  13
  14 #include <asm/processor.h>
  15 #include <asm/proto.h>
  16 #include <asm/smp.h>
  17 #include <asm/bootsetup.h>
  18 #include <asm/setup.h>
  19 #include <asm/desc.h>
  20 #include <asm/pgtable.h>
  21 #include <asm/sections.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         memset(__bss_start, 0,
  28                (unsigned long) __bss_stop - (unsigned long) __bss_start);
  29 }
  30
  31 #define NEW_CL_POINTER          0x228   /* Relative to real mode data */
  32 #define OLD_CL_MAGIC_ADDR       0x90020
  33 #define OLD_CL_MAGIC            0xA33F
  34 #define OLD_CL_BASE_ADDR        0x90000
  35 #define OLD_CL_OFFSET           0x90022
  36
  37 extern char saved_command_line[];
  38
  39 static void __init copy_bootdata(char *real_mode_data)
  40 {
  41         int new_data;
  42         char * command_line;
  43
  44         memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE);
  45         new_data = *(int *) (x86_boot_params + NEW_CL_POINTER);
  46         if (!new_data) {
  47                 if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) {
  48                         printk("so old bootloader that it does not support commandline?!\n");
  49                         return;
  50                 }
  51                 new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET;
  52                 printk("old bootloader convention, maybe loadlin?\n");
  53         }
  54         command_line = (char *) ((u64)(new_data));
  55         memcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
  56         printk("Bootdata ok (command line is %s)\n", saved_command_line);
  57 }
  58
  59 static void __init setup_boot_cpu_data(void)
  60 {
  61         unsigned int dummy, eax;
  62
  63         /* get vendor info */
  64         cpuid(0, (unsigned int *)&boot_cpu_data.cpuid_level,
  65               (unsigned int *)&boot_cpu_data.x86_vendor_id[0],
  66               (unsigned int *)&boot_cpu_data.x86_vendor_id[8],
  67               (unsigned int *)&boot_cpu_data.x86_vendor_id[4]);
  68
  69         /* get cpu type */
  70         cpuid(1, &eax, &dummy, &dummy,
  71                 (unsigned int *) &boot_cpu_data.x86_capability);
  72         boot_cpu_data.x86 = (eax >> 8) & 0xf;
  73         boot_cpu_data.x86_model = (eax >> 4) & 0xf;
  74         boot_cpu_data.x86_mask = eax & 0xf;
  75 }
  76
  77 void __init x86_64_start_kernel(char * real_mode_data)
  78 {
  79         char *s;
  80         int i;
  81
  82         for (i = 0; i < 256; i++)
  83                 set_intr_gate(i, early_idt_handler);
  84         asm volatile("lidt %0" :: "m" (idt_descr));
  85         clear_bss();
  86
  87         /*
  88          * This must be called really, really early:
  89          */
  90         lockdep_init();
  91
  92         /*
  93          * switch to init_level4_pgt from boot_level4_pgt
  94          */
  95         memcpy(init_level4_pgt, boot_level4_pgt, PTRS_PER_PGD*sizeof(pgd_t));
  96         asm volatile("movq %0,%%cr3" :: "r" (__pa_symbol(&init_level4_pgt)));
  97
  98         for (i = 0; i < NR_CPUS; i++)
  99                 cpu_pda(i) = &boot_cpu_pda[i];
 100
 101         pda_init(0);
 102         copy_bootdata(real_mode_data);
 103 #ifdef CONFIG_SMP
 104         cpu_set(0, cpu_online_map);
 105 #endif
 106         s = strstr(saved_command_line, "earlyprintk=");
 107         if (s != NULL)
 108                 setup_early_printk(strchr(s, '=') + 1);
 109 #ifdef CONFIG_NUMA
 110         s = strstr(saved_command_line, "numa=");
 111         if (s != NULL)
 112                 numa_setup(s+5);
 113 #endif
 114 #ifdef CONFIG_X86_IO_APIC
 115         if (strstr(saved_command_line, "disableapic"))
 116                 disable_apic = 1;
 117 #endif
 118         /* You need early console to see that */
 119         if (__pa_symbol(&_end) >= KERNEL_TEXT_SIZE)
 120                 panic("Kernel too big for kernel mapping\n");
 121
 122         setup_boot_cpu_data();
 123         start_kernel();
 124 }