blob: b2cc73768a9daaa5f6e568bd4977f6fea7889d87 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 *
5 * Enhanced CPU detection and feature setting code by Mike Jagdis
6 * and Martin Mares, November 1997.
7 */
8
9.text
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <linux/threads.h>
Sam Ravnborg8b2f7ff2008-01-30 13:33:28 +010011#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/linkage.h>
13#include <asm/segment.h>
14#include <asm/page.h>
15#include <asm/pgtable.h>
16#include <asm/desc.h>
17#include <asm/cache.h>
18#include <asm/thread_info.h>
Sam Ravnborg86feeaa2005-09-09 19:28:28 +020019#include <asm/asm-offsets.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <asm/setup.h>
Ian Campbell551889a2008-02-09 23:24:09 +010021#include <asm/processor-flags.h>
22
23/* Physical address */
24#define pa(X) ((X) - __PAGE_OFFSET)
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
26/*
27 * References to members of the new_cpu_data structure.
28 */
29
30#define X86 new_cpu_data+CPUINFO_x86
31#define X86_VENDOR new_cpu_data+CPUINFO_x86_vendor
32#define X86_MODEL new_cpu_data+CPUINFO_x86_model
33#define X86_MASK new_cpu_data+CPUINFO_x86_mask
34#define X86_HARD_MATH new_cpu_data+CPUINFO_hard_math
35#define X86_CPUID new_cpu_data+CPUINFO_cpuid_level
36#define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability
37#define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id
38
39/*
40 * This is how much memory *in addition to the memory covered up to
Jeremy Fitzhardinge9ce8c2e2007-05-02 19:27:16 +020041 * and including _end* we need mapped initially.
42 * We need:
43 * - one bit for each possible page, but only in low memory, which means
44 * 2^32/4096/8 = 128K worst case (4G/4G split.)
45 * - enough space to map all low memory, which means
46 * (2^32/4096) / 1024 pages (worst case, non PAE)
47 * (2^32/4096) / 512 + 4 pages (worst case for PAE)
48 * - a few pages for allocator use before the kernel pagetable has
49 * been set up
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 *
51 * Modulo rounding, each megabyte assigned here requires a kilobyte of
52 * memory, which is currently unreclaimed.
53 *
54 * This should be a multiple of a page.
55 */
Jeremy Fitzhardinge9ce8c2e2007-05-02 19:27:16 +020056LOW_PAGES = 1<<(32-PAGE_SHIFT_asm)
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Ingo Molnar1e3e1972007-10-17 18:04:34 +020058/*
59 * To preserve the DMA pool in PAGEALLOC kernels, we'll allocate
60 * pagetables from above the 16MB DMA limit, so we'll have to set
61 * up pagetables 16MB more (worst-case):
62 */
63#ifdef CONFIG_DEBUG_PAGEALLOC
64LOW_PAGES = LOW_PAGES + 0x1000000
65#endif
66
Jeremy Fitzhardinge9ce8c2e2007-05-02 19:27:16 +020067#if PTRS_PER_PMD > 1
68PAGE_TABLE_SIZE = (LOW_PAGES / PTRS_PER_PMD) + PTRS_PER_PGD
69#else
70PAGE_TABLE_SIZE = (LOW_PAGES / PTRS_PER_PGD)
71#endif
72BOOTBITMAP_SIZE = LOW_PAGES / 8
73ALLOCATOR_SLOP = 4
74
75INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_SIZE_asm
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
77/*
78 * 32-bit kernel entrypoint; only used by the boot CPU. On entry,
79 * %esi points to the real-mode code as a 32-bit pointer.
80 * CS and DS must be 4 GB flat segments, but we don't depend on
81 * any particular GDT layout, because we load our own as soon as we
82 * can.
83 */
Vivek Goyalf8657e12007-02-13 13:26:22 +010084.section .text.head,"ax",@progbits
Linus Torvalds1da177e2005-04-16 15:20:36 -070085ENTRY(startup_32)
Rusty Russella24e7852007-10-21 16:41:35 -070086 /* test KEEP_SEGMENTS flag to see if the bootloader is asking
87 us to not reload segments */
88 testb $(1<<6), BP_loadflags(%esi)
89 jnz 2f
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
91/*
92 * Set segments to known values.
93 */
Ian Campbell551889a2008-02-09 23:24:09 +010094 lgdt pa(boot_gdt_descr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070095 movl $(__BOOT_DS),%eax
96 movl %eax,%ds
97 movl %eax,%es
98 movl %eax,%fs
99 movl %eax,%gs
Rusty Russella24e7852007-10-21 16:41:35 -07001002:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
102/*
103 * Clear BSS first so that there are no surprises...
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 */
Rusty Russella24e7852007-10-21 16:41:35 -0700105 cld
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 xorl %eax,%eax
Ian Campbell551889a2008-02-09 23:24:09 +0100107 movl $pa(__bss_start),%edi
108 movl $pa(__bss_stop),%ecx
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 subl %edi,%ecx
110 shrl $2,%ecx
111 rep ; stosl
Vivek Goyal484b90c2005-09-03 15:56:31 -0700112/*
113 * Copy bootup parameters out of the way.
114 * Note: %esi still has the pointer to the real-mode data.
115 * With the kexec as boot loader, parameter segment might be loaded beyond
116 * kernel image and might not even be addressable by early boot page tables.
117 * (kexec on panic case). Hence copy out the parameters before initializing
118 * page tables.
119 */
Ian Campbell551889a2008-02-09 23:24:09 +0100120 movl $pa(boot_params),%edi
Vivek Goyal484b90c2005-09-03 15:56:31 -0700121 movl $(PARAM_SIZE/4),%ecx
122 cld
123 rep
124 movsl
Ian Campbell551889a2008-02-09 23:24:09 +0100125 movl pa(boot_params) + NEW_CL_POINTER,%esi
Vivek Goyal484b90c2005-09-03 15:56:31 -0700126 andl %esi,%esi
H. Peter Anvinfa76dab2007-10-23 22:37:25 +0200127 jz 1f # No comand line
Ian Campbell551889a2008-02-09 23:24:09 +0100128 movl $pa(boot_command_line),%edi
Vivek Goyal484b90c2005-09-03 15:56:31 -0700129 movl $(COMMAND_LINE_SIZE/4),%ecx
130 rep
131 movsl
1321:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
Rusty Russella24e7852007-10-21 16:41:35 -0700134#ifdef CONFIG_PARAVIRT
Ian Campbell551889a2008-02-09 23:24:09 +0100135 /* This is can only trip for a broken bootloader... */
136 cmpw $0x207, pa(boot_params + BP_version)
Rusty Russella24e7852007-10-21 16:41:35 -0700137 jb default_entry
138
139 /* Paravirt-compatible boot parameters. Look to see what architecture
140 we're booting under. */
Ian Campbell551889a2008-02-09 23:24:09 +0100141 movl pa(boot_params + BP_hardware_subarch), %eax
Rusty Russella24e7852007-10-21 16:41:35 -0700142 cmpl $num_subarch_entries, %eax
143 jae bad_subarch
144
Ian Campbell551889a2008-02-09 23:24:09 +0100145 movl pa(subarch_entries)(,%eax,4), %eax
Rusty Russella24e7852007-10-21 16:41:35 -0700146 subl $__PAGE_OFFSET, %eax
147 jmp *%eax
148
149bad_subarch:
150WEAK(lguest_entry)
151WEAK(xen_entry)
152 /* Unknown implementation; there's really
153 nothing we can do at this point. */
154 ud2a
Sam Ravnborg8b2f7ff2008-01-30 13:33:28 +0100155
156 __INITDATA
157
Rusty Russella24e7852007-10-21 16:41:35 -0700158subarch_entries:
159 .long default_entry /* normal x86/PC */
160 .long lguest_entry /* lguest hypervisor */
161 .long xen_entry /* Xen hypervisor */
162num_subarch_entries = (. - subarch_entries) / 4
163.previous
164#endif /* CONFIG_PARAVIRT */
165
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166/*
167 * Initialize page tables. This creates a PDE and a set of page
168 * tables, which are located immediately beyond _end. The variable
169 * init_pg_tables_end is set up to point to the first "safe" location.
170 * Mappings are created both at virtual address 0 (identity mapping)
171 * and PAGE_OFFSET for up to _end+sizeof(page tables)+INIT_MAP_BEYOND_END.
172 *
Ian Campbell551889a2008-02-09 23:24:09 +0100173 * Note that the stack is not yet set up!
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 */
Ian Campbell551889a2008-02-09 23:24:09 +0100175#define PTE_ATTR 0x007 /* PRESENT+RW+USER */
176#define PDE_ATTR 0x067 /* PRESENT+RW+USER+DIRTY+ACCESSED */
177#define PGD_ATTR 0x001 /* PRESENT (no other attributes) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178
Rusty Russella24e7852007-10-21 16:41:35 -0700179default_entry:
Ian Campbell551889a2008-02-09 23:24:09 +0100180#ifdef CONFIG_X86_PAE
181
182 /*
183 * In PAE mode swapper_pg_dir is statically defined to contain enough
184 * entries to cover the VMSPLIT option (that is the top 1, 2 or 3
185 * entries). The identity mapping is handled by pointing two PGD
186 * entries to the first kernel PMD.
187 *
188 * Note the upper half of each PMD or PTE are always zero at
189 * this stage.
190 */
191
192#define KPMDS ((0x100000000-__PAGE_OFFSET) >> 30) /* Number of kernel PMDs */
193
194 xorl %ebx,%ebx /* %ebx is kept at zero */
195
196 movl $pa(pg0), %edi
197 movl $pa(swapper_pg_pmd), %edx
198 movl $PTE_ATTR, %eax
Linus Torvalds1da177e2005-04-16 15:20:36 -070019910:
Ian Campbell551889a2008-02-09 23:24:09 +0100200 leal PDE_ATTR(%edi),%ecx /* Create PMD entry */
201 movl %ecx,(%edx) /* Store PMD entry */
202 /* Upper half already zero */
203 addl $8,%edx
204 movl $512,%ecx
20511:
206 stosl
207 xchgl %eax,%ebx
208 stosl
209 xchgl %eax,%ebx
210 addl $0x1000,%eax
211 loop 11b
212
213 /*
214 * End condition: we must map up to and including INIT_MAP_BEYOND_END
215 * bytes beyond the end of our own page tables.
216 */
217 leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp
218 cmpl %ebp,%eax
219 jb 10b
2201:
221 movl %edi,pa(init_pg_tables_end)
222
223 /* Do early initialization of the fixmap area */
224 movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax
225 movl %eax,pa(swapper_pg_pmd+0x1000*KPMDS-8)
226#else /* Not PAE */
227
228page_pde_offset = (__PAGE_OFFSET >> 20);
229
230 movl $pa(pg0), %edi
231 movl $pa(swapper_pg_dir), %edx
232 movl $PTE_ATTR, %eax
23310:
234 leal PDE_ATTR(%edi),%ecx /* Create PDE entry */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 movl %ecx,(%edx) /* Store identity PDE entry */
236 movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */
237 addl $4,%edx
238 movl $1024, %ecx
23911:
240 stosl
241 addl $0x1000,%eax
242 loop 11b
Ian Campbell551889a2008-02-09 23:24:09 +0100243 /*
244 * End condition: we must map up to and including INIT_MAP_BEYOND_END
245 * bytes beyond the end of our own page tables; the +0x007 is
246 * the attribute bits
247 */
248 leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 cmpl %ebp,%eax
250 jb 10b
Ian Campbell551889a2008-02-09 23:24:09 +0100251 movl %edi,pa(init_pg_tables_end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252
Ian Campbell551889a2008-02-09 23:24:09 +0100253 /* Do early initialization of the fixmap area */
254 movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax
255 movl %eax,pa(swapper_pg_dir+0xffc)
256#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 jmp 3f
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258/*
259 * Non-boot CPU entry point; entered from trampoline.S
260 * We can't lgdt here, because lgdt itself uses a data segment, but
Sebastien Dugue52de74d2007-05-02 19:27:10 +0200261 * we know the trampoline has already loaded the boot_gdt for us.
Vivek Goyalf8657e12007-02-13 13:26:22 +0100262 *
263 * If cpu hotplug is not supported then this code can go in init section
264 * which will be freed later
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 */
Vivek Goyalf8657e12007-02-13 13:26:22 +0100266
Andi Kleen5fe44862007-08-10 22:31:10 +0200267#ifndef CONFIG_HOTPLUG_CPU
Vivek Goyalf8657e12007-02-13 13:26:22 +0100268.section .init.text,"ax",@progbits
269#endif
270
271#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272ENTRY(startup_32_smp)
273 cld
274 movl $(__BOOT_DS),%eax
275 movl %eax,%ds
276 movl %eax,%es
277 movl %eax,%fs
278 movl %eax,%gs
Ian Campbell5756dd52008-01-30 13:33:27 +0100279#endif /* CONFIG_SMP */
2803:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
282/*
283 * New page tables may be in 4Mbyte page mode and may
284 * be using the global pages.
285 *
286 * NOTE! If we are on a 486 we may have no cr4 at all!
287 * So we do not try to touch it unless we really have
288 * some bits in it to set. This won't work if the BSP
289 * implements cr4 but this AP does not -- very unlikely
290 * but be warned! The same applies to the pse feature
291 * if not equally supported. --macro
292 *
293 * NOTE! We have to correct for the fact that we're
294 * not yet offset PAGE_OFFSET..
295 */
Ian Campbell551889a2008-02-09 23:24:09 +0100296#define cr4_bits pa(mmu_cr4_features)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 movl cr4_bits,%edx
298 andl %edx,%edx
299 jz 6f
300 movl %cr4,%eax # Turn on paging options (PSE,PAE,..)
301 orl %edx,%eax
302 movl %eax,%cr4
303
304 btl $5, %eax # check if PAE is enabled
305 jnc 6f
306
307 /* Check if extended functions are implemented */
308 movl $0x80000000, %eax
309 cpuid
310 cmpl $0x80000000, %eax
311 jbe 6f
312 mov $0x80000001, %eax
313 cpuid
314 /* Execute Disable bit supported? */
315 btl $20, %edx
316 jnc 6f
317
318 /* Setup EFER (Extended Feature Enable Register) */
319 movl $0xc0000080, %ecx
320 rdmsr
321
322 btsl $11, %eax
323 /* Make changes effective */
324 wrmsr
325
3266:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327
328/*
329 * Enable paging
330 */
Ian Campbell551889a2008-02-09 23:24:09 +0100331 movl $pa(swapper_pg_dir),%eax
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 movl %eax,%cr3 /* set the page table pointer.. */
333 movl %cr0,%eax
Ian Campbell551889a2008-02-09 23:24:09 +0100334 orl $X86_CR0_PG,%eax
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 movl %eax,%cr0 /* ..and set paging (PG) bit */
336 ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */
3371:
338 /* Set up the stack pointer */
339 lss stack_start,%esp
340
341/*
342 * Initialize eflags. Some BIOS's leave bits like NT set. This would
343 * confuse the debugger if this code is traced.
344 * XXX - best to initialize before switching to protected mode.
345 */
346 pushl $0
347 popfl
348
349#ifdef CONFIG_SMP
Ian Campbell50359502008-01-30 13:33:27 +0100350 cmpb $0, ready
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 jz 1f /* Initial CPU cleans BSS */
352 jmp checkCPUtype
3531:
354#endif /* CONFIG_SMP */
355
356/*
357 * start system 32-bit setup. We need to re-do some of the things done
358 * in 16-bit mode for the "real" operations.
359 */
360 call setup_idt
361
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362checkCPUtype:
363
364 movl $-1,X86_CPUID # -1 for no CPUID initially
365
366/* check if it is 486 or 386. */
367/*
368 * XXX - this does a lot of unnecessary setup. Alignment checks don't
369 * apply at our cpl of 0 and the stack ought to be aligned already, and
370 * we don't need to preserve eflags.
371 */
372
373 movb $3,X86 # at least 386
374 pushfl # push EFLAGS
375 popl %eax # get EFLAGS
376 movl %eax,%ecx # save original EFLAGS
377 xorl $0x240000,%eax # flip AC and ID bits in EFLAGS
378 pushl %eax # copy to EFLAGS
379 popfl # set EFLAGS
380 pushfl # get new EFLAGS
381 popl %eax # put it in eax
382 xorl %ecx,%eax # change in flags
383 pushl %ecx # restore original EFLAGS
384 popfl
385 testl $0x40000,%eax # check if AC bit changed
386 je is386
387
388 movb $4,X86 # at least 486
389 testl $0x200000,%eax # check if ID bit changed
390 je is486
391
392 /* get vendor info */
393 xorl %eax,%eax # call CPUID with 0 -> return vendor ID
394 cpuid
395 movl %eax,X86_CPUID # save CPUID level
396 movl %ebx,X86_VENDOR_ID # lo 4 chars
397 movl %edx,X86_VENDOR_ID+4 # next 4 chars
398 movl %ecx,X86_VENDOR_ID+8 # last 4 chars
399
400 orl %eax,%eax # do we have processor info as well?
401 je is486
402
403 movl $1,%eax # Use the CPUID instruction to get CPU type
404 cpuid
405 movb %al,%cl # save reg for future use
406 andb $0x0f,%ah # mask processor family
407 movb %ah,X86
408 andb $0xf0,%al # mask model
409 shrb $4,%al
410 movb %al,X86_MODEL
411 andb $0x0f,%cl # mask mask revision
412 movb %cl,X86_MASK
413 movl %edx,X86_CAPABILITY
414
415is486: movl $0x50022,%ecx # set AM, WP, NE and MP
416 jmp 2f
417
418is386: movl $2,%ecx # set MP
4192: movl %cr0,%eax
420 andl $0x80000011,%eax # Save PG,PE,ET
421 orl %ecx,%eax
422 movl %eax,%cr0
423
424 call check_x87
Rusty Russell2a57ff12007-02-13 13:26:26 +0100425 lgdt early_gdt_descr
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 lidt idt_descr
427 ljmp $(__KERNEL_CS),$1f
4281: movl $(__KERNEL_DS),%eax # reload all the segment registers
429 movl %eax,%ss # after changing gdt.
Jeremy Fitzhardinge7c3576d2007-05-02 19:27:16 +0200430 movl %eax,%fs # gets reset once there's real percpu
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431
432 movl $(__USER_DS),%eax # DS/ES contains default USER segment
433 movl %eax,%ds
434 movl %eax,%es
435
Jeremy Fitzhardinge464d1a72007-02-13 13:26:20 +0100436 xorl %eax,%eax # Clear GS and LDT
437 movl %eax,%gs
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 lldt %ax
Jeremy Fitzhardingef95d47c2006-12-07 02:14:02 +0100439
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 cld # gcc2 wants the direction flag cleared at all times
Jeremy Fitzhardinge26fd5e02006-10-21 18:37:02 +0200441 pushl $0 # fake return address for unwinder
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442#ifdef CONFIG_SMP
Shaohua Lid92de652005-06-25 14:54:49 -0700443 movb ready, %cl
444 movb $1, ready
Andi Kleen29fe5f32006-08-30 19:37:09 +0200445 cmpb $0,%cl # the first CPU calls start_kernel
Jeremy Fitzhardinge7c3576d2007-05-02 19:27:16 +0200446 je 1f
447 movl $(__KERNEL_PERCPU), %eax
448 movl %eax,%fs # set this cpu's percpu
449 jmp initialize_secondary # all other CPUs call initialize_secondary
4501:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451#endif /* CONFIG_SMP */
Eric W. Biederman700efc12008-02-23 09:58:20 +0100452 jmp i386_start_kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
454/*
455 * We depend on ET to be correct. This checks for 287/387.
456 */
457check_x87:
458 movb $0,X86_HARD_MATH
459 clts
460 fninit
461 fstsw %ax
462 cmpb $0,%al
463 je 1f
464 movl %cr0,%eax /* no coprocessor: have to set bits */
465 xorl $4,%eax /* set EM */
466 movl %eax,%cr0
467 ret
468 ALIGN
4691: movb $1,X86_HARD_MATH
470 .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */
471 ret
472
473/*
474 * setup_idt
475 *
476 * sets up a idt with 256 entries pointing to
477 * ignore_int, interrupt gates. It doesn't actually load
478 * idt - that can be done only after paging has been enabled
479 * and the kernel moved to PAGE_OFFSET. Interrupts
480 * are enabled elsewhere, when we can be relatively
481 * sure everything is ok.
482 *
483 * Warning: %esi is live across this function.
484 */
485setup_idt:
486 lea ignore_int,%edx
487 movl $(__KERNEL_CS << 16),%eax
488 movw %dx,%ax /* selector = 0x0010 = cs */
489 movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
490
491 lea idt_table,%edi
492 mov $256,%ecx
493rp_sidt:
494 movl %eax,(%edi)
495 movl %edx,4(%edi)
496 addl $8,%edi
497 dec %ecx
498 jne rp_sidt
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200499
500.macro set_early_handler handler,trapno
501 lea \handler,%edx
502 movl $(__KERNEL_CS << 16),%eax
503 movw %dx,%ax
504 movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
505 lea idt_table,%edi
506 movl %eax,8*\trapno(%edi)
507 movl %edx,8*\trapno+4(%edi)
508.endm
509
510 set_early_handler handler=early_divide_err,trapno=0
511 set_early_handler handler=early_illegal_opcode,trapno=6
512 set_early_handler handler=early_protection_fault,trapno=13
513 set_early_handler handler=early_page_fault,trapno=14
514
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 ret
516
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200517early_divide_err:
518 xor %edx,%edx
519 pushl $0 /* fake errcode */
520 jmp early_fault
521
522early_illegal_opcode:
523 movl $6,%edx
524 pushl $0 /* fake errcode */
525 jmp early_fault
526
527early_protection_fault:
528 movl $13,%edx
529 jmp early_fault
530
531early_page_fault:
532 movl $14,%edx
533 jmp early_fault
534
535early_fault:
536 cld
537#ifdef CONFIG_PRINTK
Ingo Molnar382f64a2007-10-17 18:04:41 +0200538 pusha
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200539 movl $(__KERNEL_DS),%eax
540 movl %eax,%ds
541 movl %eax,%es
542 cmpl $2,early_recursion_flag
543 je hlt_loop
544 incl early_recursion_flag
545 movl %cr2,%eax
546 pushl %eax
547 pushl %edx /* trapno */
548 pushl $fault_msg
549#ifdef CONFIG_EARLY_PRINTK
550 call early_printk
551#else
552 call printk
553#endif
554#endif
Ingo Molnar94878ef2008-01-30 13:33:09 +0100555 call dump_stack
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200556hlt_loop:
557 hlt
558 jmp hlt_loop
559
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560/* This is the default interrupt "handler" :-) */
561 ALIGN
562ignore_int:
563 cld
Matt Mackalld59745c2005-05-01 08:59:02 -0700564#ifdef CONFIG_PRINTK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 pushl %eax
566 pushl %ecx
567 pushl %edx
568 pushl %es
569 pushl %ds
570 movl $(__KERNEL_DS),%eax
571 movl %eax,%ds
572 movl %eax,%es
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200573 cmpl $2,early_recursion_flag
574 je hlt_loop
575 incl early_recursion_flag
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 pushl 16(%esp)
577 pushl 24(%esp)
578 pushl 32(%esp)
579 pushl 40(%esp)
580 pushl $int_msg
Ingo Molnarc0cdf192006-02-11 17:55:56 -0800581#ifdef CONFIG_EARLY_PRINTK
582 call early_printk
583#else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 call printk
Ingo Molnarc0cdf192006-02-11 17:55:56 -0800585#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 addl $(5*4),%esp
587 popl %ds
588 popl %es
589 popl %edx
590 popl %ecx
591 popl %eax
Matt Mackalld59745c2005-05-01 08:59:02 -0700592#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 iret
594
Vivek Goyalf8657e12007-02-13 13:26:22 +0100595.section .text
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596/*
597 * Real beginning of normal "text" segment
598 */
599ENTRY(stext)
600ENTRY(_stext)
601
602/*
603 * BSS section
604 */
Jeremy Fitzhardinge5ead97c2007-07-17 18:37:04 -0700605.section ".bss.page_aligned","wa"
606 .align PAGE_SIZE_asm
Ian Campbell551889a2008-02-09 23:24:09 +0100607#ifdef CONFIG_X86_PAE
Adrian Bunked2b7e22008-02-22 21:58:37 +0200608swapper_pg_pmd:
Ian Campbell551889a2008-02-09 23:24:09 +0100609 .fill 1024*KPMDS,4,0
610#else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611ENTRY(swapper_pg_dir)
612 .fill 1024,4,0
Ian Campbell551889a2008-02-09 23:24:09 +0100613#endif
Adrian Bunkaa65af3f2008-02-13 23:29:55 +0200614swapper_pg_fixmap:
Eric W. Bidermanb1c931e2007-07-15 23:37:28 -0700615 .fill 1024,4,0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616ENTRY(empty_zero_page)
617 .fill 4096,1,0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618/*
619 * This starts the data section.
620 */
Ian Campbell551889a2008-02-09 23:24:09 +0100621#ifdef CONFIG_X86_PAE
622.section ".data.page_aligned","wa"
623 /* Page-aligned for the benefit of paravirt? */
624 .align PAGE_SIZE_asm
625ENTRY(swapper_pg_dir)
626 .long pa(swapper_pg_pmd+PGD_ATTR),0 /* low identity map */
627# if KPMDS == 3
628 .long pa(swapper_pg_pmd+PGD_ATTR),0
629 .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0
630 .long pa(swapper_pg_pmd+PGD_ATTR+0x2000),0
631# elif KPMDS == 2
632 .long 0,0
633 .long pa(swapper_pg_pmd+PGD_ATTR),0
634 .long pa(swapper_pg_pmd+PGD_ATTR+0x1000),0
635# elif KPMDS == 1
636 .long 0,0
637 .long 0,0
638 .long pa(swapper_pg_pmd+PGD_ATTR),0
639# else
640# error "Kernel PMDs should be 1, 2 or 3"
641# endif
642 .align PAGE_SIZE_asm /* needs to be page-sized too */
643#endif
644
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645.data
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646ENTRY(stack_start)
647 .long init_thread_union+THREAD_SIZE
648 .long __BOOT_DS
649
650ready: .byte 0
651
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200652early_recursion_flag:
653 .long 0
654
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655int_msg:
656 .asciz "Unknown interrupt or fault at EIP %p %p %p\n"
657
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200658fault_msg:
Vegard Nossum575ca732008-04-25 21:02:34 +0200659/* fault info: */
660 .ascii "BUG: Int %d: CR2 %p\n"
661/* pusha regs: */
662 .ascii " EDI %p ESI %p EBP %p ESP %p\n"
663 .ascii " EBX %p EDX %p ECX %p EAX %p\n"
664/* fault frame: */
665 .ascii " err %p EIP %p CS %p flg %p\n"
666 .ascii "Stack: %p %p %p %p %p %p %p %p\n"
667 .ascii " %p %p %p %p %p %p %p %p\n"
668 .asciz " %p %p %p %p %p %p %p %p\n"
Chuck Ebbertec5c0922006-09-26 10:52:39 +0200669
Thomas Gleixner97027852007-10-11 11:16:51 +0200670#include "../../x86/xen/xen-head.S"
Jeremy Fitzhardinge5ead97c2007-07-17 18:37:04 -0700671
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672/*
673 * The IDT and GDT 'descriptors' are a strange 48-bit object
674 * only used by the lidt and lgdt instructions. They are not
675 * like usual segment descriptors - they consist of a 16-bit
676 * segment size, and 32-bit linear address value:
677 */
678
679.globl boot_gdt_descr
680.globl idt_descr
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681
682 ALIGN
683# early boot GDT descriptor (must use 1:1 address mapping)
684 .word 0 # 32 bit align gdt_desc.address
685boot_gdt_descr:
686 .word __BOOT_DS+7
Sebastien Dugue52de74d2007-05-02 19:27:10 +0200687 .long boot_gdt - __PAGE_OFFSET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688
689 .word 0 # 32-bit align idt_desc.address
690idt_descr:
691 .word IDT_ENTRIES*8-1 # idt contains 256 entries
692 .long idt_table
693
694# boot GDT descriptor (later on used by CPU#0):
695 .word 0 # 32 bit align gdt_desc.address
Rusty Russell2a57ff12007-02-13 13:26:26 +0100696ENTRY(early_gdt_descr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 .word GDT_ENTRIES*8-1
Jeremy Fitzhardinge7a61d352007-05-02 19:27:15 +0200698 .long per_cpu__gdt_page /* Overwritten for secondary CPUs */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700/*
Sebastien Dugue52de74d2007-05-02 19:27:10 +0200701 * The boot_gdt must mirror the equivalent in setup.S and is
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 * used only for booting.
703 */
704 .align L1_CACHE_BYTES
Sebastien Dugue52de74d2007-05-02 19:27:10 +0200705ENTRY(boot_gdt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 .fill GDT_ENTRY_BOOT_CS,8,0
707 .quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */
708 .quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */