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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/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 max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT;
80
81 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
82#ifdef CONFIG_EARLY_PRINTK
83 set_intr_gate(i, &early_idt_handlers[i]);
84#else
85 set_intr_gate(i, early_idt_handler);
86#endif
87 }
88 load_idt((const struct desc_ptr *)&idt_descr);
89
90 if (console_loglevel == 10)
91 early_printk("Kernel alive\n");
92
93 x86_64_start_reservations(real_mode_data);
94}
95
96void __init x86_64_start_reservations(char *real_mode_data)
97{
98 copy_bootdata(__va(real_mode_data));
99
100 memblock_reserve(__pa_symbol(&_text),
101 __pa_symbol(&__bss_stop) - __pa_symbol(&_text));
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 memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
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}
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/bios_ebda.h>
28#include <asm/bootparam_utils.h>
29#include <asm/microcode.h>
30#include <asm/kasan.h>
31
32/*
33 * Manage page tables very early on.
34 */
35extern pgd_t early_level4_pgt[PTRS_PER_PGD];
36extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
37static unsigned int __initdata next_early_pgt = 2;
38pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
39
40/* Wipe all early page tables except for the kernel symbol map */
41static void __init reset_early_page_tables(void)
42{
43 memset(early_level4_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
44 next_early_pgt = 0;
45 write_cr3(__pa_nodebug(early_level4_pgt));
46}
47
48/* Create a new PMD entry */
49int __init early_make_pgtable(unsigned long address)
50{
51 unsigned long physaddr = address - __PAGE_OFFSET;
52 pgdval_t pgd, *pgd_p;
53 pudval_t pud, *pud_p;
54 pmdval_t pmd, *pmd_p;
55
56 /* Invalid address or early pgt is done ? */
57 if (physaddr >= MAXMEM || read_cr3() != __pa_nodebug(early_level4_pgt))
58 return -1;
59
60again:
61 pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
62 pgd = *pgd_p;
63
64 /*
65 * The use of __START_KERNEL_map rather than __PAGE_OFFSET here is
66 * critical -- __PAGE_OFFSET would point us back into the dynamic
67 * range and we might end up looping forever...
68 */
69 if (pgd)
70 pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
71 else {
72 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
73 reset_early_page_tables();
74 goto again;
75 }
76
77 pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
78 memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
79 *pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
80 }
81 pud_p += pud_index(address);
82 pud = *pud_p;
83
84 if (pud)
85 pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
86 else {
87 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
88 reset_early_page_tables();
89 goto again;
90 }
91
92 pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
93 memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
94 *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
95 }
96 pmd = (physaddr & PMD_MASK) + early_pmd_flags;
97 pmd_p[pmd_index(address)] = pmd;
98
99 return 0;
100}
101
102/* Don't add a printk in there. printk relies on the PDA which is not initialized
103 yet. */
104static void __init clear_bss(void)
105{
106 memset(__bss_start, 0,
107 (unsigned long) __bss_stop - (unsigned long) __bss_start);
108}
109
110static unsigned long get_cmd_line_ptr(void)
111{
112 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
113
114 cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
115
116 return cmd_line_ptr;
117}
118
119static void __init copy_bootdata(char *real_mode_data)
120{
121 char * command_line;
122 unsigned long cmd_line_ptr;
123
124 memcpy(&boot_params, real_mode_data, sizeof boot_params);
125 sanitize_boot_params(&boot_params);
126 cmd_line_ptr = get_cmd_line_ptr();
127 if (cmd_line_ptr) {
128 command_line = __va(cmd_line_ptr);
129 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
130 }
131}
132
133asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
134{
135 int i;
136
137 /*
138 * Build-time sanity checks on the kernel image and module
139 * area mappings. (these are purely build-time and produce no code)
140 */
141 BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map);
142 BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE);
143 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
144 BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0);
145 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
146 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
147 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
148 (__START_KERNEL & PGDIR_MASK)));
149 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
150
151 cr4_init_shadow();
152
153 /* Kill off the identity-map trampoline */
154 reset_early_page_tables();
155
156 clear_bss();
157
158 clear_page(init_level4_pgt);
159
160 kasan_early_init();
161
162 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
163 set_intr_gate(i, early_idt_handler_array[i]);
164 load_idt((const struct desc_ptr *)&idt_descr);
165
166 copy_bootdata(__va(real_mode_data));
167
168 /*
169 * Load microcode early on BSP.
170 */
171 load_ucode_bsp();
172
173 /* set init_level4_pgt kernel high mapping*/
174 init_level4_pgt[511] = early_level4_pgt[511];
175
176 x86_64_start_reservations(real_mode_data);
177}
178
179void __init x86_64_start_reservations(char *real_mode_data)
180{
181 /* version is always not zero if it is copied */
182 if (!boot_params.hdr.version)
183 copy_bootdata(__va(real_mode_data));
184
185 reserve_ebda_region();
186
187 switch (boot_params.hdr.hardware_subarch) {
188 case X86_SUBARCH_INTEL_MID:
189 x86_intel_mid_early_setup();
190 break;
191 default:
192 break;
193 }
194
195 start_kernel();
196}