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/bios_ebda.h>
27 #include <asm/trampoline.h>
28
29 /* boot cpu pda */
30 static struct x8664_pda _boot_cpu_pda;
31
32 #ifdef CONFIG_SMP
33 /*
34 * We install an empty cpu_pda pointer table to indicate to early users
35 * (numa_set_node) that the cpu_pda pointer table for cpus other than
36 * the boot cpu is not yet setup.
37 */
38 static struct x8664_pda *__cpu_pda[NR_CPUS] __initdata;
39 #else
40 static struct x8664_pda *__cpu_pda[NR_CPUS] __read_mostly;
41 #endif
42
x86_64_init_pda(void)43 void __init x86_64_init_pda(void)
44 {
45 _cpu_pda = __cpu_pda;
46 cpu_pda(0) = &_boot_cpu_pda;
47 pda_init(0);
48 }
49
zap_identity_mappings(void)50 static void __init zap_identity_mappings(void)
51 {
52 pgd_t *pgd = pgd_offset_k(0UL);
53 pgd_clear(pgd);
54 __flush_tlb_all();
55 }
56
57 /* Don't add a printk in there. printk relies on the PDA which is not initialized
58 yet. */
clear_bss(void)59 static void __init clear_bss(void)
60 {
61 memset(__bss_start, 0,
62 (unsigned long) __bss_stop - (unsigned long) __bss_start);
63 }
64
copy_bootdata(char * real_mode_data)65 static void __init copy_bootdata(char *real_mode_data)
66 {
67 char * command_line;
68
69 memcpy(&boot_params, real_mode_data, sizeof boot_params);
70 if (boot_params.hdr.cmd_line_ptr) {
71 command_line = __va(boot_params.hdr.cmd_line_ptr);
72 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
73 }
74 }
75
x86_64_start_kernel(char * real_mode_data)76 void __init x86_64_start_kernel(char * real_mode_data)
77 {
78 int i;
79
80 /*
81 * Build-time sanity checks on the kernel image and module
82 * area mappings. (these are purely build-time and produce no code)
83 */
84 BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START);
85 BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE);
86 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
87 BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0);
88 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
89 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
90 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
91 (__START_KERNEL & PGDIR_MASK)));
92 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
93
94 /* clear bss before set_intr_gate with early_idt_handler */
95 clear_bss();
96
97 /* Make NULL pointers segfault */
98 zap_identity_mappings();
99
100 /* Cleanup the over mapped high alias */
101 cleanup_highmap();
102
103 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
104 #ifdef CONFIG_EARLY_PRINTK
105 set_intr_gate(i, &early_idt_handlers[i]);
106 #else
107 set_intr_gate(i, early_idt_handler);
108 #endif
109 }
110 load_idt((const struct desc_ptr *)&idt_descr);
111
112 if (console_loglevel == 10)
113 early_printk("Kernel alive\n");
114
115 x86_64_init_pda();
116
117 x86_64_start_reservations(real_mode_data);
118 }
119
x86_64_start_reservations(char * real_mode_data)120 void __init x86_64_start_reservations(char *real_mode_data)
121 {
122 copy_bootdata(__va(real_mode_data));
123
124 reserve_trampoline_memory();
125
126 reserve_early(__pa_symbol(&_text), __pa_symbol(&_end), "TEXT DATA BSS");
127
128 #ifdef CONFIG_BLK_DEV_INITRD
129 /* Reserve INITRD */
130 if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
131 unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
132 unsigned long ramdisk_size = boot_params.hdr.ramdisk_size;
133 unsigned long ramdisk_end = ramdisk_image + ramdisk_size;
134 reserve_early(ramdisk_image, ramdisk_end, "RAMDISK");
135 }
136 #endif
137
138 reserve_ebda_region();
139
140 /*
141 * At this point everything still needed from the boot loader
142 * or BIOS or kernel text should be early reserved or marked not
143 * RAM in e820. All other memory is free game.
144 */
145
146 start_kernel();
147 }
148