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 #include <linux/memblock.h> 16 17 #include <asm/processor.h> 18 #include <asm/proto.h> 19 #include <asm/smp.h> 20 #include <asm/setup.h> 21 #include <asm/desc.h> 22 #include <asm/pgtable.h> 23 #include <asm/tlbflush.h> 24 #include <asm/sections.h> 25 #include <asm/kdebug.h> 26 #include <asm/e820.h> 27 #include <asm/trampoline.h> 28 #include <asm/bios_ebda.h> 29 30 static void __init zap_identity_mappings(void) 31 { 32 pgd_t *pgd = pgd_offset_k(0UL); 33 pgd_clear(pgd); 34 __flush_tlb_all(); 35 } 36 37 /* Don't add a printk in there. printk relies on the PDA which is not initialized 38 yet. */ 39 static void __init clear_bss(void) 40 { 41 memset(__bss_start, 0, 42 (unsigned long) __bss_stop - (unsigned long) __bss_start); 43 } 44 45 static void __init copy_bootdata(char *real_mode_data) 46 { 47 char * command_line; 48 49 memcpy(&boot_params, real_mode_data, sizeof boot_params); 50 if (boot_params.hdr.cmd_line_ptr) { 51 command_line = __va(boot_params.hdr.cmd_line_ptr); 52 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); 53 } 54 } 55 56 void __init x86_64_start_kernel(char * real_mode_data) 57 { 58 int i; 59 60 /* 61 * Build-time sanity checks on the kernel image and module 62 * area mappings. (these are purely build-time and produce no code) 63 */ 64 BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START); 65 BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE); 66 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); 67 BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0); 68 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); 69 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); 70 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == 71 (__START_KERNEL & PGDIR_MASK))); 72 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END); 73 74 /* clear bss before set_intr_gate with early_idt_handler */ 75 clear_bss(); 76 77 /* Make NULL pointers segfault */ 78 zap_identity_mappings(); 79 80 max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT; 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 97 void __init x86_64_start_reservations(char *real_mode_data) 98 { 99 copy_bootdata(__va(real_mode_data)); 100 101 memblock_init(); 102 103 memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS"); 104 105 #ifdef CONFIG_BLK_DEV_INITRD 106 /* Reserve INITRD */ 107 if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) { 108 /* Assume only end is not page aligned */ 109 unsigned long ramdisk_image = boot_params.hdr.ramdisk_image; 110 unsigned long ramdisk_size = boot_params.hdr.ramdisk_size; 111 unsigned long ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size); 112 memblock_x86_reserve_range(ramdisk_image, ramdisk_end, "RAMDISK"); 113 } 114 #endif 115 116 reserve_ebda_region(); 117 118 /* 119 * At this point everything still needed from the boot loader 120 * or BIOS or kernel text should be early reserved or marked not 121 * RAM in e820. All other memory is free game. 122 */ 123 124 start_kernel(); 125 } 126