2 * prepare to run common code
4 * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
7 #define DISABLE_BRANCH_PROFILING
8 #include <linux/init.h>
9 #include <linux/linkage.h>
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/percpu.h>
14 #include <linux/start_kernel.h>
16 #include <linux/memblock.h>
18 #include <asm/processor.h>
19 #include <asm/proto.h>
21 #include <asm/setup.h>
23 #include <asm/pgtable.h>
24 #include <asm/tlbflush.h>
25 #include <asm/sections.h>
26 #include <asm/kdebug.h>
28 #include <asm/bios_ebda.h>
29 #include <asm/bootparam_utils.h>
30 #include <asm/microcode.h>
31 #include <asm/kasan.h>
34 * Manage page tables very early on.
36 extern pgd_t early_level4_pgt[PTRS_PER_PGD];
37 extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
38 static unsigned int __initdata next_early_pgt = 2;
39 pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
41 /* Wipe all early page tables except for the kernel symbol map */
42 static void __init reset_early_page_tables(void)
44 memset(early_level4_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
46 write_cr3(__pa_nodebug(early_level4_pgt));
49 /* Create a new PMD entry */
50 int __init early_make_pgtable(unsigned long address)
52 unsigned long physaddr = address - __PAGE_OFFSET;
57 /* Invalid address or early pgt is done ? */
58 if (physaddr >= MAXMEM || read_cr3() != __pa_nodebug(early_level4_pgt))
62 pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
66 * The use of __START_KERNEL_map rather than __PAGE_OFFSET here is
67 * critical -- __PAGE_OFFSET would point us back into the dynamic
68 * range and we might end up looping forever...
71 pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
73 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
74 reset_early_page_tables();
78 pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
79 memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
80 *pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
82 pud_p += pud_index(address);
86 pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
88 if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
89 reset_early_page_tables();
93 pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
94 memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
95 *pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
97 pmd = (physaddr & PMD_MASK) + early_pmd_flags;
98 pmd_p[pmd_index(address)] = pmd;
103 /* Don't add a printk in there. printk relies on the PDA which is not initialized
105 static void __init clear_bss(void)
107 memset(__bss_start, 0,
108 (unsigned long) __bss_stop - (unsigned long) __bss_start);
109 memset(__brk_base, 0,
110 (unsigned long) __brk_limit - (unsigned long) __brk_base);
113 static unsigned long get_cmd_line_ptr(void)
115 unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
117 cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
122 static void __init copy_bootdata(char *real_mode_data)
125 unsigned long cmd_line_ptr;
127 memcpy(&boot_params, real_mode_data, sizeof boot_params);
128 sanitize_boot_params(&boot_params);
129 cmd_line_ptr = get_cmd_line_ptr();
131 command_line = __va(cmd_line_ptr);
132 memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
136 asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
141 * Build-time sanity checks on the kernel image and module
142 * area mappings. (these are purely build-time and produce no code)
144 BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map);
145 BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE);
146 BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
147 BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0);
148 BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
149 BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
150 BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
151 (__START_KERNEL & PGDIR_MASK)));
152 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
156 /* Kill off the identity-map trampoline */
157 reset_early_page_tables();
161 clear_page(init_level4_pgt);
165 for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
166 set_intr_gate(i, early_idt_handler_array[i]);
167 load_idt((const struct desc_ptr *)&idt_descr);
169 copy_bootdata(__va(real_mode_data));
172 * Load microcode early on BSP.
176 /* set init_level4_pgt kernel high mapping*/
177 init_level4_pgt[511] = early_level4_pgt[511];
179 x86_64_start_reservations(real_mode_data);
182 void __init x86_64_start_reservations(char *real_mode_data)
184 /* version is always not zero if it is copied */
185 if (!boot_params.hdr.version)
186 copy_bootdata(__va(real_mode_data));
188 x86_early_init_platform_quirks();
190 switch (boot_params.hdr.hardware_subarch) {
191 case X86_SUBARCH_INTEL_MID:
192 x86_intel_mid_early_setup();