2 * prepare to run common code
4 * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
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>
15 #include <linux/memblock.h>
17 #include <asm/processor.h>
18 #include <asm/proto.h>
20 #include <asm/setup.h>
22 #include <asm/pgtable.h>
23 #include <asm/tlbflush.h>
24 #include <asm/sections.h>
25 #include <asm/kdebug.h>
27 #include <asm/bios_ebda.h>
28 #include <asm/bootparam_utils.h>
29 #include <asm/microcode.h>
30 #include <asm/kasan.h>
33 * Manage page tables very early on.
35 extern pgd_t early_level4_pgt
[PTRS_PER_PGD
];
36 extern pmd_t early_dynamic_pgts
[EARLY_DYNAMIC_PAGE_TABLES
][PTRS_PER_PMD
];
37 static unsigned int __initdata next_early_pgt
= 2;
38 pmdval_t early_pmd_flags
= __PAGE_KERNEL_LARGE
& ~(_PAGE_GLOBAL
| _PAGE_NX
);
40 /* Wipe all early page tables except for the kernel symbol map */
41 static void __init
reset_early_page_tables(void)
43 memset(early_level4_pgt
, 0, sizeof(pgd_t
)*(PTRS_PER_PGD
-1));
45 write_cr3(__pa_nodebug(early_level4_pgt
));
48 /* Create a new PMD entry */
49 int __init
early_make_pgtable(unsigned long address
)
51 unsigned long physaddr
= address
- __PAGE_OFFSET
;
56 /* Invalid address or early pgt is done ? */
57 if (physaddr
>= MAXMEM
|| read_cr3() != __pa_nodebug(early_level4_pgt
))
61 pgd_p
= &early_level4_pgt
[pgd_index(address
)].pgd
;
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...
70 pud_p
= (pudval_t
*)((pgd
& PTE_PFN_MASK
) + __START_KERNEL_map
- phys_base
);
72 if (next_early_pgt
>= EARLY_DYNAMIC_PAGE_TABLES
) {
73 reset_early_page_tables();
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
;
81 pud_p
+= pud_index(address
);
85 pmd_p
= (pmdval_t
*)((pud
& PTE_PFN_MASK
) + __START_KERNEL_map
- phys_base
);
87 if (next_early_pgt
>= EARLY_DYNAMIC_PAGE_TABLES
) {
88 reset_early_page_tables();
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
;
96 pmd
= (physaddr
& PMD_MASK
) + early_pmd_flags
;
97 pmd_p
[pmd_index(address
)] = pmd
;
102 /* Don't add a printk in there. printk relies on the PDA which is not initialized
104 static void __init
clear_bss(void)
106 memset(__bss_start
, 0,
107 (unsigned long) __bss_stop
- (unsigned long) __bss_start
);
110 static unsigned long get_cmd_line_ptr(void)
112 unsigned long cmd_line_ptr
= boot_params
.hdr
.cmd_line_ptr
;
114 cmd_line_ptr
|= (u64
)boot_params
.ext_cmd_line_ptr
<< 32;
119 static void __init
copy_bootdata(char *real_mode_data
)
122 unsigned long cmd_line_ptr
;
124 memcpy(&boot_params
, real_mode_data
, sizeof boot_params
);
125 sanitize_boot_params(&boot_params
);
126 cmd_line_ptr
= get_cmd_line_ptr();
128 command_line
= __va(cmd_line_ptr
);
129 memcpy(boot_command_line
, command_line
, COMMAND_LINE_SIZE
);
133 asmlinkage __visible
void __init
x86_64_start_kernel(char * real_mode_data
)
138 * Build-time sanity checks on the kernel image and module
139 * area mappings. (these are purely build-time and produce no code)
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
);
153 /* Kill off the identity-map trampoline */
154 reset_early_page_tables();
158 clear_page(init_level4_pgt
);
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
);
166 copy_bootdata(__va(real_mode_data
));
169 * Load microcode early on BSP.
173 /* set init_level4_pgt kernel high mapping*/
174 init_level4_pgt
[511] = early_level4_pgt
[511];
176 x86_64_start_reservations(real_mode_data
);
179 void __init
x86_64_start_reservations(char *real_mode_data
)
181 /* version is always not zero if it is copied */
182 if (!boot_params
.hdr
.version
)
183 copy_bootdata(__va(real_mode_data
));
185 reserve_ebda_region();
187 switch (boot_params
.hdr
.hardware_subarch
) {
188 case X86_SUBARCH_INTEL_MID
:
189 x86_intel_mid_early_setup();