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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-05 17:55:20 -0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-05-05 17:55:20 -0400
commitea62ccd00fd0b6720b033adfc9984f31130ce195 (patch)
tree9837b797b2466fffcb0af96c388b06eae9c3df18 /arch/x86_64/kernel/head.S
parent886a0768affe9a32f18c45f8e1393bca9ece5392 (diff)
parent35060b6a9a4e1c89bc6fbea61090e302dbc61847 (diff)
Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (231 commits) [PATCH] i386: Don't delete cpu_devs data to identify different x86 types in late_initcall [PATCH] i386: type may be unused [PATCH] i386: Some additional chipset register values validation. [PATCH] i386: Add missing !X86_PAE dependincy to the 2G/2G split. [PATCH] x86-64: Don't exclude asm-offsets.c in Documentation/dontdiff [PATCH] i386: avoid redundant preempt_disable in __unlazy_fpu [PATCH] i386: white space fixes in i387.h [PATCH] i386: Drop noisy e820 debugging printks [PATCH] x86-64: Fix allnoconfig error in genapic_flat.c [PATCH] x86-64: Shut up warnings for vfat compat ioctls on other file systems [PATCH] x86-64: Share identical video.S between i386 and x86-64 [PATCH] x86-64: Remove CONFIG_REORDER [PATCH] x86-64: Print type and size correctly for unknown compat ioctls [PATCH] i386: Remove copy_*_user BUG_ONs for (size < 0) [PATCH] i386: Little cleanups in smpboot.c [PATCH] x86-64: Don't enable NUMA for a single node in K8 NUMA scanning [PATCH] x86: Use RDTSCP for synchronous get_cycles if possible [PATCH] i386: Add X86_FEATURE_RDTSCP [PATCH] i386: Implement X86_FEATURE_SYNC_RDTSC on i386 [PATCH] i386: Implement alternative_io for i386 ... Fix up trivial conflict in include/linux/highmem.h manually. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86_64/kernel/head.S')
-rw-r--r--arch/x86_64/kernel/head.S340
1 files changed, 169 insertions, 171 deletions
diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index 598a4d0351fc..1fab487dee86 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -5,6 +5,7 @@
5 * Copyright (C) 2000 Pavel Machek <pavel@suse.cz> 5 * Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
6 * Copyright (C) 2000 Karsten Keil <kkeil@suse.de> 6 * Copyright (C) 2000 Karsten Keil <kkeil@suse.de>
7 * Copyright (C) 2001,2002 Andi Kleen <ak@suse.de> 7 * Copyright (C) 2001,2002 Andi Kleen <ak@suse.de>
8 * Copyright (C) 2005 Eric Biederman <ebiederm@xmission.com>
8 */ 9 */
9 10
10 11
@@ -13,97 +14,131 @@
13#include <linux/init.h> 14#include <linux/init.h>
14#include <asm/desc.h> 15#include <asm/desc.h>
15#include <asm/segment.h> 16#include <asm/segment.h>
17#include <asm/pgtable.h>
16#include <asm/page.h> 18#include <asm/page.h>
17#include <asm/msr.h> 19#include <asm/msr.h>
18#include <asm/cache.h> 20#include <asm/cache.h>
19 21
20/* we are not able to switch in one step to the final KERNEL ADRESS SPACE 22/* we are not able to switch in one step to the final KERNEL ADRESS SPACE
21 * because we need identity-mapped pages on setup so define __START_KERNEL to 23 * because we need identity-mapped pages.
22 * 0x100000 for this stage 24 *
23 *
24 */ 25 */
25 26
26 .text 27 .text
27 .section .bootstrap.text 28 .section .bootstrap.text
28 .code32 29 .code64
29 .globl startup_32 30 .globl startup_64
30/* %bx: 1 if coming from smp trampoline on secondary cpu */ 31startup_64:
31startup_32: 32
32
33 /* 33 /*
34 * At this point the CPU runs in 32bit protected mode (CS.D = 1) with 34 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
35 * paging disabled and the point of this file is to switch to 64bit 35 * and someone has loaded an identity mapped page table
36 * long mode with a kernel mapping for kerneland to jump into the 36 * for us. These identity mapped page tables map all of the
37 * kernel virtual addresses. 37 * kernel pages and possibly all of memory.
38 * There is no stack until we set one up. 38 *
39 * %esi holds a physical pointer to real_mode_data.
40 *
41 * We come here either directly from a 64bit bootloader, or from
42 * arch/x86_64/boot/compressed/head.S.
43 *
44 * We only come here initially at boot nothing else comes here.
45 *
46 * Since we may be loaded at an address different from what we were
47 * compiled to run at we first fixup the physical addresses in our page
48 * tables and then reload them.
39 */ 49 */
40 50
41 /* Initialize the %ds segment register */ 51 /* Compute the delta between the address I am compiled to run at and the
42 movl $__KERNEL_DS,%eax 52 * address I am actually running at.
43 movl %eax,%ds
44
45 /* Load new GDT with the 64bit segments using 32bit descriptor */
46 lgdt pGDT32 - __START_KERNEL_map
47
48 /* If the CPU doesn't support CPUID this will double fault.
49 * Unfortunately it is hard to check for CPUID without a stack.
50 */ 53 */
51 54 leaq _text(%rip), %rbp
52 /* Check if extended functions are implemented */ 55 subq $_text - __START_KERNEL_map, %rbp
53 movl $0x80000000, %eax 56
54 cpuid 57 /* Is the address not 2M aligned? */
55 cmpl $0x80000000, %eax 58 movq %rbp, %rax
56 jbe no_long_mode 59 andl $~LARGE_PAGE_MASK, %eax
57 /* Check if long mode is implemented */ 60 testl %eax, %eax
58 mov $0x80000001, %eax 61 jnz bad_address
59 cpuid 62
60 btl $29, %edx 63 /* Is the address too large? */
61 jnc no_long_mode 64 leaq _text(%rip), %rdx
62 65 movq $PGDIR_SIZE, %rax
63 /* 66 cmpq %rax, %rdx
64 * Prepare for entering 64bits mode 67 jae bad_address
68
69 /* Fixup the physical addresses in the page table
65 */ 70 */
71 addq %rbp, init_level4_pgt + 0(%rip)
72 addq %rbp, init_level4_pgt + (258*8)(%rip)
73 addq %rbp, init_level4_pgt + (511*8)(%rip)
74
75 addq %rbp, level3_ident_pgt + 0(%rip)
76 addq %rbp, level3_kernel_pgt + (510*8)(%rip)
77
78 /* Add an Identity mapping if I am above 1G */
79 leaq _text(%rip), %rdi
80 andq $LARGE_PAGE_MASK, %rdi
81
82 movq %rdi, %rax
83 shrq $PUD_SHIFT, %rax
84 andq $(PTRS_PER_PUD - 1), %rax
85 jz ident_complete
86
87 leaq (level2_spare_pgt - __START_KERNEL_map + _KERNPG_TABLE)(%rbp), %rdx
88 leaq level3_ident_pgt(%rip), %rbx
89 movq %rdx, 0(%rbx, %rax, 8)
90
91 movq %rdi, %rax
92 shrq $PMD_SHIFT, %rax
93 andq $(PTRS_PER_PMD - 1), %rax
94 leaq __PAGE_KERNEL_LARGE_EXEC(%rdi), %rdx
95 leaq level2_spare_pgt(%rip), %rbx
96 movq %rdx, 0(%rbx, %rax, 8)
97ident_complete:
98
99 /* Fixup the kernel text+data virtual addresses
100 */
101 leaq level2_kernel_pgt(%rip), %rdi
102 leaq 4096(%rdi), %r8
103 /* See if it is a valid page table entry */
1041: testq $1, 0(%rdi)
105 jz 2f
106 addq %rbp, 0(%rdi)
107 /* Go to the next page */
1082: addq $8, %rdi
109 cmp %r8, %rdi
110 jne 1b
111
112 /* Fixup phys_base */
113 addq %rbp, phys_base(%rip)
66 114
67 /* Enable PAE mode */ 115#ifdef CONFIG_SMP
68 xorl %eax, %eax 116 addq %rbp, trampoline_level4_pgt + 0(%rip)
69 btsl $5, %eax 117 addq %rbp, trampoline_level4_pgt + (511*8)(%rip)
70 movl %eax, %cr4 118#endif
71 119#ifdef CONFIG_ACPI_SLEEP
72 /* Setup early boot stage 4 level pagetables */ 120 addq %rbp, wakeup_level4_pgt + 0(%rip)
73 movl $(boot_level4_pgt - __START_KERNEL_map), %eax 121 addq %rbp, wakeup_level4_pgt + (511*8)(%rip)
74 movl %eax, %cr3 122#endif
75
76 /* Setup EFER (Extended Feature Enable Register) */
77 movl $MSR_EFER, %ecx
78 rdmsr
79
80 /* Enable Long Mode */
81 btsl $_EFER_LME, %eax
82
83 /* Make changes effective */
84 wrmsr
85 123
86 xorl %eax, %eax 124 /* Due to ENTRY(), sometimes the empty space gets filled with
87 btsl $31, %eax /* Enable paging and in turn activate Long Mode */ 125 * zeros. Better take a jmp than relying on empty space being
88 btsl $0, %eax /* Enable protected mode */ 126 * filled with 0x90 (nop)
89 /* Make changes effective */
90 movl %eax, %cr0
91 /*
92 * At this point we're in long mode but in 32bit compatibility mode
93 * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
94 * EFER.LMA = 1). Now we want to jump in 64bit mode, to do that we use
95 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
96 */ 127 */
97 ljmp $__KERNEL_CS, $(startup_64 - __START_KERNEL_map) 128 jmp secondary_startup_64
98 129ENTRY(secondary_startup_64)
99 .code64 130 /*
100 .org 0x100 131 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
101 .globl startup_64 132 * and someone has loaded a mapped page table.
102startup_64: 133 *
103 /* We come here either from startup_32 134 * %esi holds a physical pointer to real_mode_data.
104 * or directly from a 64bit bootloader. 135 *
105 * Since we may have come directly from a bootloader we 136 * We come here either from startup_64 (using physical addresses)
106 * reload the page tables here. 137 * or from trampoline.S (using virtual addresses).
138 *
139 * Using virtual addresses from trampoline.S removes the need
140 * to have any identity mapped pages in the kernel page table
141 * after the boot processor executes this code.
107 */ 142 */
108 143
109 /* Enable PAE mode and PGE */ 144 /* Enable PAE mode and PGE */
@@ -113,9 +148,15 @@ startup_64:
113 movq %rax, %cr4 148 movq %rax, %cr4
114 149
115 /* Setup early boot stage 4 level pagetables. */ 150 /* Setup early boot stage 4 level pagetables. */
116 movq $(boot_level4_pgt - __START_KERNEL_map), %rax 151 movq $(init_level4_pgt - __START_KERNEL_map), %rax
152 addq phys_base(%rip), %rax
117 movq %rax, %cr3 153 movq %rax, %cr3
118 154
155 /* Ensure I am executing from virtual addresses */
156 movq $1f, %rax
157 jmp *%rax
1581:
159
119 /* Check if nx is implemented */ 160 /* Check if nx is implemented */
120 movl $0x80000001, %eax 161 movl $0x80000001, %eax
121 cpuid 162 cpuid
@@ -124,17 +165,11 @@ startup_64:
124 /* Setup EFER (Extended Feature Enable Register) */ 165 /* Setup EFER (Extended Feature Enable Register) */
125 movl $MSR_EFER, %ecx 166 movl $MSR_EFER, %ecx
126 rdmsr 167 rdmsr
127 168 btsl $_EFER_SCE, %eax /* Enable System Call */
128 /* Enable System Call */ 169 btl $20,%edi /* No Execute supported? */
129 btsl $_EFER_SCE, %eax
130
131 /* No Execute supported? */
132 btl $20,%edi
133 jnc 1f 170 jnc 1f
134 btsl $_EFER_NX, %eax 171 btsl $_EFER_NX, %eax
1351: 1721: wrmsr /* Make changes effective */
136 /* Make changes effective */
137 wrmsr
138 173
139 /* Setup cr0 */ 174 /* Setup cr0 */
140#define CR0_PM 1 /* protected mode */ 175#define CR0_PM 1 /* protected mode */
@@ -161,7 +196,7 @@ startup_64:
161 * addresses where we're currently running on. We have to do that here 196 * addresses where we're currently running on. We have to do that here
162 * because in 32bit we couldn't load a 64bit linear address. 197 * because in 32bit we couldn't load a 64bit linear address.
163 */ 198 */
164 lgdt cpu_gdt_descr 199 lgdt cpu_gdt_descr(%rip)
165 200
166 /* set up data segments. actually 0 would do too */ 201 /* set up data segments. actually 0 would do too */
167 movl $__KERNEL_DS,%eax 202 movl $__KERNEL_DS,%eax
@@ -212,6 +247,9 @@ initial_code:
212init_rsp: 247init_rsp:
213 .quad init_thread_union+THREAD_SIZE-8 248 .quad init_thread_union+THREAD_SIZE-8
214 249
250bad_address:
251 jmp bad_address
252
215ENTRY(early_idt_handler) 253ENTRY(early_idt_handler)
216 cmpl $2,early_recursion_flag(%rip) 254 cmpl $2,early_recursion_flag(%rip)
217 jz 1f 255 jz 1f
@@ -240,110 +278,66 @@ early_idt_msg:
240early_idt_ripmsg: 278early_idt_ripmsg:
241 .asciz "RIP %s\n" 279 .asciz "RIP %s\n"
242 280
243.code32 281.balign PAGE_SIZE
244ENTRY(no_long_mode)
245 /* This isn't an x86-64 CPU so hang */
2461:
247 jmp 1b
248
249.org 0xf00
250 .globl pGDT32
251pGDT32:
252 .word gdt_end-cpu_gdt_table-1
253 .long cpu_gdt_table-__START_KERNEL_map
254
255.org 0xf10
256ljumpvector:
257 .long startup_64-__START_KERNEL_map
258 .word __KERNEL_CS
259 282
260ENTRY(stext)
261ENTRY(_stext)
262
263 $page = 0
264#define NEXT_PAGE(name) \ 283#define NEXT_PAGE(name) \
265 $page = $page + 1; \ 284 .balign PAGE_SIZE; \
266 .org $page * 0x1000; \
267 phys_/**/name = $page * 0x1000 + __PHYSICAL_START; \
268ENTRY(name) 285ENTRY(name)
269 286
287/* Automate the creation of 1 to 1 mapping pmd entries */
288#define PMDS(START, PERM, COUNT) \
289 i = 0 ; \
290 .rept (COUNT) ; \
291 .quad (START) + (i << 21) + (PERM) ; \
292 i = i + 1 ; \
293 .endr
294
295 /*
296 * This default setting generates an ident mapping at address 0x100000
297 * and a mapping for the kernel that precisely maps virtual address
298 * 0xffffffff80000000 to physical address 0x000000. (always using
299 * 2Mbyte large pages provided by PAE mode)
300 */
270NEXT_PAGE(init_level4_pgt) 301NEXT_PAGE(init_level4_pgt)
271 /* This gets initialized in x86_64_start_kernel */ 302 .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
272 .fill 512,8,0 303 .fill 257,8,0
304 .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
305 .fill 252,8,0
306 /* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
307 .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
273 308
274NEXT_PAGE(level3_ident_pgt) 309NEXT_PAGE(level3_ident_pgt)
275 .quad phys_level2_ident_pgt | 0x007 310 .quad level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
276 .fill 511,8,0 311 .fill 511,8,0
277 312
278NEXT_PAGE(level3_kernel_pgt) 313NEXT_PAGE(level3_kernel_pgt)
279 .fill 510,8,0 314 .fill 510,8,0
280 /* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */ 315 /* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */
281 .quad phys_level2_kernel_pgt | 0x007 316 .quad level2_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
282 .fill 1,8,0 317 .fill 1,8,0
283 318
284NEXT_PAGE(level2_ident_pgt) 319NEXT_PAGE(level2_ident_pgt)
285 /* 40MB for bootup. */ 320 /* Since I easily can, map the first 1G.
286 i = 0 321 * Don't set NX because code runs from these pages.
287 .rept 20 322 */
288 .quad i << 21 | 0x083 323 PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC, PTRS_PER_PMD)
289 i = i + 1 324
290 .endr
291 /* Temporary mappings for the super early allocator in arch/x86_64/mm/init.c */
292 .globl temp_boot_pmds
293temp_boot_pmds:
294 .fill 492,8,0
295
296NEXT_PAGE(level2_kernel_pgt) 325NEXT_PAGE(level2_kernel_pgt)
297 /* 40MB kernel mapping. The kernel code cannot be bigger than that. 326 /* 40MB kernel mapping. The kernel code cannot be bigger than that.
298 When you change this change KERNEL_TEXT_SIZE in page.h too. */ 327 When you change this change KERNEL_TEXT_SIZE in page.h too. */
299 /* (2^48-(2*1024*1024*1024)-((2^39)*511)-((2^30)*510)) = 0 */ 328 /* (2^48-(2*1024*1024*1024)-((2^39)*511)-((2^30)*510)) = 0 */
300 i = 0 329 PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC|_PAGE_GLOBAL,
301 .rept 20 330 KERNEL_TEXT_SIZE/PMD_SIZE)
302 .quad i << 21 | 0x183
303 i = i + 1
304 .endr
305 /* Module mapping starts here */ 331 /* Module mapping starts here */
306 .fill 492,8,0 332 .fill (PTRS_PER_PMD - (KERNEL_TEXT_SIZE/PMD_SIZE)),8,0
307 333
308NEXT_PAGE(level3_physmem_pgt) 334NEXT_PAGE(level2_spare_pgt)
309 .quad phys_level2_kernel_pgt | 0x007 /* so that __va works even before pagetable_init */ 335 .fill 512,8,0
310 .fill 511,8,0
311 336
337#undef PMDS
312#undef NEXT_PAGE 338#undef NEXT_PAGE
313 339
314 .data 340 .data
315
316#ifdef CONFIG_ACPI_SLEEP
317 .align PAGE_SIZE
318ENTRY(wakeup_level4_pgt)
319 .quad phys_level3_ident_pgt | 0x007
320 .fill 255,8,0
321 .quad phys_level3_physmem_pgt | 0x007
322 .fill 254,8,0
323 /* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
324 .quad phys_level3_kernel_pgt | 0x007
325#endif
326
327#ifndef CONFIG_HOTPLUG_CPU
328 __INITDATA
329#endif
330 /*
331 * This default setting generates an ident mapping at address 0x100000
332 * and a mapping for the kernel that precisely maps virtual address
333 * 0xffffffff80000000 to physical address 0x000000. (always using
334 * 2Mbyte large pages provided by PAE mode)
335 */
336 .align PAGE_SIZE
337ENTRY(boot_level4_pgt)
338 .quad phys_level3_ident_pgt | 0x007
339 .fill 255,8,0
340 .quad phys_level3_physmem_pgt | 0x007
341 .fill 254,8,0
342 /* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
343 .quad phys_level3_kernel_pgt | 0x007
344
345 .data
346
347 .align 16 341 .align 16
348 .globl cpu_gdt_descr 342 .globl cpu_gdt_descr
349cpu_gdt_descr: 343cpu_gdt_descr:
@@ -357,6 +351,10 @@ gdt:
357 .endr 351 .endr
358#endif 352#endif
359 353
354ENTRY(phys_base)
355 /* This must match the first entry in level2_kernel_pgt */
356 .quad 0x0000000000000000
357
360/* We need valid kernel segments for data and code in long mode too 358/* We need valid kernel segments for data and code in long mode too
361 * IRET will check the segment types kkeil 2000/10/28 359 * IRET will check the segment types kkeil 2000/10/28
362 * Also sysret mandates a special GDT layout 360 * Also sysret mandates a special GDT layout
@@ -370,13 +368,13 @@ gdt:
370 368
371ENTRY(cpu_gdt_table) 369ENTRY(cpu_gdt_table)
372 .quad 0x0000000000000000 /* NULL descriptor */ 370 .quad 0x0000000000000000 /* NULL descriptor */
371 .quad 0x00cf9b000000ffff /* __KERNEL32_CS */
372 .quad 0x00af9b000000ffff /* __KERNEL_CS */
373 .quad 0x00cf93000000ffff /* __KERNEL_DS */
374 .quad 0x00cffb000000ffff /* __USER32_CS */
375 .quad 0x00cff3000000ffff /* __USER_DS, __USER32_DS */
376 .quad 0x00affb000000ffff /* __USER_CS */
373 .quad 0x0 /* unused */ 377 .quad 0x0 /* unused */
374 .quad 0x00af9a000000ffff /* __KERNEL_CS */
375 .quad 0x00cf92000000ffff /* __KERNEL_DS */
376 .quad 0x00cffa000000ffff /* __USER32_CS */
377 .quad 0x00cff2000000ffff /* __USER_DS, __USER32_DS */
378 .quad 0x00affa000000ffff /* __USER_CS */
379 .quad 0x00cf9a000000ffff /* __KERNEL32_CS */
380 .quad 0,0 /* TSS */ 378 .quad 0,0 /* TSS */
381 .quad 0,0 /* LDT */ 379 .quad 0,0 /* LDT */
382 .quad 0,0,0 /* three TLS descriptors */ 380 .quad 0,0,0 /* three TLS descriptors */