arch/x86_64/kernel/head64-xen.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  *  Jun Nakajima <jun.nakajima@intel.com>
   7  *      Modified for Xen.
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/linkage.h>
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <linux/string.h>
  15 #include <linux/percpu.h>
  16 #include <linux/module.h>
  17
  18 #include <asm/processor.h>
  19 #include <asm/proto.h>
  20 #include <asm/smp.h>
  21 #include <asm/bootsetup.h>
  22 #include <asm/setup.h>
  23 #include <asm/desc.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/sections.h>
  26
  27 unsigned long start_pfn;
  28
  29 /* Don't add a printk in there. printk relies on the PDA which is not initialized
  30    yet. */
  31 #if 0
  32 static void __init clear_bss(void)
  33 {
  34         memset(__bss_start, 0,
  35                (unsigned long) __bss_stop - (unsigned long) __bss_start);
  36 }
  37 #endif
  38
  39 #define NEW_CL_POINTER          0x228   /* Relative to real mode data */
  40 #define OLD_CL_MAGIC_ADDR       0x90020
  41 #define OLD_CL_MAGIC            0xA33F
  42 #define OLD_CL_BASE_ADDR        0x90000
  43 #define OLD_CL_OFFSET           0x90022
  44
  45 extern char saved_command_line[];
  46
  47 static void __init copy_bootdata(char *real_mode_data)
  48 {
  49 #ifndef CONFIG_XEN
  50         int new_data;
  51         char * command_line;
  52
  53         memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE);
  54         new_data = *(int *) (x86_boot_params + NEW_CL_POINTER);
  55         if (!new_data) {
  56                 if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) {
  57                         printk("so old bootloader that it does not support commandline?!\n");
  58                         return;
  59                 }
  60                 new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET;
  61                 printk("old bootloader convention, maybe loadlin?\n");
  62         }
  63         command_line = (char *) ((u64)(new_data));
  64         memcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
  65 #else
  66         int max_cmdline;
  67
  68         if ((max_cmdline = MAX_GUEST_CMDLINE) > COMMAND_LINE_SIZE)
  69                 max_cmdline = COMMAND_LINE_SIZE;
  70         memcpy(saved_command_line, xen_start_info->cmd_line, max_cmdline);
  71         saved_command_line[max_cmdline-1] = '\0';
  72 #endif
  73         printk("Bootdata ok (command line is %s)\n", saved_command_line);
  74 }
  75
  76 static void __init setup_boot_cpu_data(void)
  77 {
  78         unsigned int dummy, eax;
  79
  80         /* get vendor info */
  81         cpuid(0, (unsigned int *)&boot_cpu_data.cpuid_level,
  82               (unsigned int *)&boot_cpu_data.x86_vendor_id[0],
  83               (unsigned int *)&boot_cpu_data.x86_vendor_id[8],
  84               (unsigned int *)&boot_cpu_data.x86_vendor_id[4]);
  85
  86         /* get cpu type */
  87         cpuid(1, &eax, &dummy, &dummy,
  88                 (unsigned int *) &boot_cpu_data.x86_capability);
  89         boot_cpu_data.x86 = (eax >> 8) & 0xf;
  90         boot_cpu_data.x86_model = (eax >> 4) & 0xf;
  91         boot_cpu_data.x86_mask = eax & 0xf;
  92 }
  93
  94 #include <xen/interface/memory.h>
  95 unsigned long *machine_to_phys_mapping;
  96 EXPORT_SYMBOL(machine_to_phys_mapping);
  97 unsigned int machine_to_phys_order;
  98 EXPORT_SYMBOL(machine_to_phys_order);
  99
 100 void __init x86_64_start_kernel(char * real_mode_data)
 101 {
 102         struct xen_machphys_mapping mapping;
 103         unsigned long machine_to_phys_nr_ents;
 104         char *s;
 105         int i;
 106
 107         xen_start_info = (struct start_info *)real_mode_data;
 108         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 109                 phys_to_machine_mapping =
 110                         (unsigned long *)xen_start_info->mfn_list;
 111                 start_pfn = (__pa(xen_start_info->pt_base) >> PAGE_SHIFT) +
 112                         xen_start_info->nr_pt_frames;
 113         }
 114
 115         machine_to_phys_mapping = (unsigned long *)MACH2PHYS_VIRT_START;
 116         machine_to_phys_nr_ents = MACH2PHYS_NR_ENTRIES;
 117         if (HYPERVISOR_memory_op(XENMEM_machphys_mapping, &mapping) == 0) {
 118                 machine_to_phys_mapping = (unsigned long *)mapping.v_start;
 119                 machine_to_phys_nr_ents = mapping.max_mfn + 1;
 120         }
 121         while ((1UL << machine_to_phys_order) < machine_to_phys_nr_ents )
 122                 machine_to_phys_order++;
 123
 124 #if 0
 125         for (i = 0; i < 256; i++)
 126                 set_intr_gate(i, early_idt_handler);
 127         asm volatile("lidt %0" :: "m" (idt_descr));
 128 #endif
 129
 130         /*
 131          * This must be called really, really early:
 132          */
 133         lockdep_init();
 134
 135         for (i = 0; i < NR_CPUS; i++)
 136                 cpu_pda(i) = &boot_cpu_pda[i];
 137
 138         pda_init(0);
 139         copy_bootdata(real_mode_data);
 140 #ifdef CONFIG_SMP
 141         cpu_set(0, cpu_online_map);
 142 #endif
 143         s = strstr(saved_command_line, "earlyprintk=");
 144         if (s != NULL)
 145                 setup_early_printk(strchr(s, '=') + 1);
 146 #ifdef CONFIG_NUMA
 147         s = strstr(saved_command_line, "numa=");
 148         if (s != NULL)
 149                 numa_setup(s+5);
 150 #endif
 151 #ifdef CONFIG_X86_IO_APIC
 152         if (strstr(saved_command_line, "disableapic"))
 153                 disable_apic = 1;
 154 #endif
 155         /* You need early console to see that */
 156         if (__pa_symbol(&_end) >= KERNEL_TEXT_SIZE)
 157                 panic("Kernel too big for kernel mapping\n");
 158
 159         setup_boot_cpu_data();
 160         start_kernel();
 161 }