1/* 2 * 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#include <linux/start_kernel.h> 14#include <linux/io.h> 15 16#include <asm/processor.h> 17#include <asm/proto.h> 18#include <asm/smp.h> 19#include <asm/setup.h> 20#include <asm/desc.h> 21#include <asm/pgtable.h> 22#include <asm/tlbflush.h> 23#include <asm/sections.h> 24#include <asm/kdebug.h> 25#include <asm/e820.h> 26#include <asm/trampoline.h> 27#include <asm/bios_ebda.h> 28 29static void __init zap_identity_mappings(void) 30{ 31 pgd_t *pgd = pgd_offset_k(0UL); 32 pgd_clear(pgd); 33 __flush_tlb_all(); 34} 35 36/* Don't add a printk in there. printk relies on the PDA which is not initialized 37 yet. */ 38static void __init clear_bss(void) 39{ 40 memset(__bss_start, 0, 41 (unsigned long) __bss_stop - (unsigned long) __bss_start); 42} 43 44static void __init copy_bootdata(char *real_mode_data) 45{ 46 char * command_line; 47 48 memcpy(&boot_params, real_mode_data, sizeof boot_params); 49 if (boot_params.hdr.cmd_line_ptr) { 50 command_line = __va(boot_params.hdr.cmd_line_ptr); 51 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); 52 } 53} 54 55void __init x86_64_start_kernel(char * real_mode_data) 56{ 57 int i; 58 59 /* 60 * Build-time sanity checks on the kernel image and module 61 * area mappings. (these are purely build-time and produce no code) 62 */ 63 BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START); 64 BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE); 65 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); 66 BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0); 67 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); 68 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); 69 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == 70 (__START_KERNEL & PGDIR_MASK))); 71 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END); 72 73 /* clear bss before set_intr_gate with early_idt_handler */ 74 clear_bss(); 75 76 /* Make NULL pointers segfault */ 77 zap_identity_mappings(); 78 79 /* Cleanup the over mapped high alias */ 80 cleanup_highmap(); 81 82 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) { 83#ifdef CONFIG_EARLY_PRINTK 84 set_intr_gate(i, &early_idt_handlers[i]); 85#else 86 set_intr_gate(i, early_idt_handler); 87#endif 88 } 89 load_idt((const struct desc_ptr *)&idt_descr); 90 91 if (console_loglevel == 10) 92 early_printk("Kernel alive\n"); 93 94 x86_64_start_reservations(real_mode_data); 95} 96 97void __init x86_64_start_reservations(char *real_mode_data) 98{ 99 copy_bootdata(__va(real_mode_data)); 100 101 reserve_early(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS"); 102 103#ifdef CONFIG_BLK_DEV_INITRD 104 /* Reserve INITRD */ 105 if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) { 106 /* Assume only end is not page aligned */ 107 unsigned long ramdisk_image = boot_params.hdr.ramdisk_image; 108 unsigned long ramdisk_size = boot_params.hdr.ramdisk_size; 109 unsigned long ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size); 110 reserve_early(ramdisk_image, ramdisk_end, "RAMDISK"); 111 } 112#endif 113 114 reserve_ebda_region(); 115 116 /* 117 * At this point everything still needed from the boot loader 118 * or BIOS or kernel text should be early reserved or marked not 119 * RAM in e820. All other memory is free game. 120 */ 121 122 start_kernel(); 123} 124