Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * |
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 | |
1da177e4 | 10 | #include <linux/threads.h> |
8b2f7fff | 11 | #include <linux/init.h> |
1da177e4 LT |
12 | #include <linux/linkage.h> |
13 | #include <asm/segment.h> | |
0341c14d JF |
14 | #include <asm/page_types.h> |
15 | #include <asm/pgtable_types.h> | |
1da177e4 LT |
16 | #include <asm/cache.h> |
17 | #include <asm/thread_info.h> | |
86feeaa8 | 18 | #include <asm/asm-offsets.h> |
1da177e4 | 19 | #include <asm/setup.h> |
551889a6 | 20 | #include <asm/processor-flags.h> |
8a50e513 PA |
21 | #include <asm/msr-index.h> |
22 | #include <asm/cpufeature.h> | |
60a5317f | 23 | #include <asm/percpu.h> |
4c5023a3 | 24 | #include <asm/nops.h> |
551889a6 IC |
25 | |
26 | /* Physical address */ | |
27 | #define pa(X) ((X) - __PAGE_OFFSET) | |
1da177e4 LT |
28 | |
29 | /* | |
30 | * References to members of the new_cpu_data structure. | |
31 | */ | |
32 | ||
33 | #define X86 new_cpu_data+CPUINFO_x86 | |
34 | #define X86_VENDOR new_cpu_data+CPUINFO_x86_vendor | |
35 | #define X86_MODEL new_cpu_data+CPUINFO_x86_model | |
36 | #define X86_MASK new_cpu_data+CPUINFO_x86_mask | |
37 | #define X86_HARD_MATH new_cpu_data+CPUINFO_hard_math | |
38 | #define X86_CPUID new_cpu_data+CPUINFO_cpuid_level | |
39 | #define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability | |
40 | #define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id | |
41 | ||
42 | /* | |
c090f532 JF |
43 | * This is how much memory in addition to the memory covered up to |
44 | * and including _end we need mapped initially. | |
9ce8c2ed | 45 | * We need: |
2bd2753f YL |
46 | * (KERNEL_IMAGE_SIZE/4096) / 1024 pages (worst case, non PAE) |
47 | * (KERNEL_IMAGE_SIZE/4096) / 512 + 4 pages (worst case for PAE) | |
1da177e4 LT |
48 | * |
49 | * Modulo rounding, each megabyte assigned here requires a kilobyte of | |
50 | * memory, which is currently unreclaimed. | |
51 | * | |
52 | * This should be a multiple of a page. | |
2bd2753f YL |
53 | * |
54 | * KERNEL_IMAGE_SIZE should be greater than pa(_end) | |
55 | * and small than max_low_pfn, otherwise will waste some page table entries | |
1da177e4 | 56 | */ |
1da177e4 | 57 | |
9ce8c2ed | 58 | #if PTRS_PER_PMD > 1 |
c090f532 | 59 | #define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD) |
9ce8c2ed | 60 | #else |
c090f532 | 61 | #define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD) |
9ce8c2ed | 62 | #endif |
9ce8c2ed | 63 | |
147dd561 PA |
64 | /* Number of possible pages in the lowmem region */ |
65 | LOWMEM_PAGES = (((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT) | |
66 | ||
c090f532 | 67 | /* Enough space to fit pagetables for the low memory linear map */ |
147dd561 | 68 | MAPPING_BEYOND_END = PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT |
c090f532 JF |
69 | |
70 | /* | |
71 | * Worst-case size of the kernel mapping we need to make: | |
147dd561 PA |
72 | * a relocatable kernel can live anywhere in lowmem, so we need to be able |
73 | * to map all of lowmem. | |
c090f532 | 74 | */ |
147dd561 | 75 | KERNEL_PAGES = LOWMEM_PAGES |
c090f532 | 76 | |
7bf04be8 | 77 | INIT_MAP_SIZE = PAGE_TABLE_SIZE(KERNEL_PAGES) * PAGE_SIZE |
2bd2753f | 78 | RESERVE_BRK(pagetables, INIT_MAP_SIZE) |
796216a5 | 79 | |
1da177e4 LT |
80 | /* |
81 | * 32-bit kernel entrypoint; only used by the boot CPU. On entry, | |
82 | * %esi points to the real-mode code as a 32-bit pointer. | |
83 | * CS and DS must be 4 GB flat segments, but we don't depend on | |
84 | * any particular GDT layout, because we load our own as soon as we | |
85 | * can. | |
86 | */ | |
4ae59b91 | 87 | __HEAD |
1da177e4 | 88 | ENTRY(startup_32) |
11d4c3f9 PA |
89 | movl pa(stack_start),%ecx |
90 | ||
a24e7851 RR |
91 | /* test KEEP_SEGMENTS flag to see if the bootloader is asking |
92 | us to not reload segments */ | |
93 | testb $(1<<6), BP_loadflags(%esi) | |
94 | jnz 2f | |
1da177e4 LT |
95 | |
96 | /* | |
97 | * Set segments to known values. | |
98 | */ | |
551889a6 | 99 | lgdt pa(boot_gdt_descr) |
1da177e4 LT |
100 | movl $(__BOOT_DS),%eax |
101 | movl %eax,%ds | |
102 | movl %eax,%es | |
103 | movl %eax,%fs | |
104 | movl %eax,%gs | |
11d4c3f9 | 105 | movl %eax,%ss |
a24e7851 | 106 | 2: |
11d4c3f9 | 107 | leal -__PAGE_OFFSET(%ecx),%esp |
1da177e4 LT |
108 | |
109 | /* | |
110 | * Clear BSS first so that there are no surprises... | |
1da177e4 | 111 | */ |
a24e7851 | 112 | cld |
1da177e4 | 113 | xorl %eax,%eax |
551889a6 IC |
114 | movl $pa(__bss_start),%edi |
115 | movl $pa(__bss_stop),%ecx | |
1da177e4 LT |
116 | subl %edi,%ecx |
117 | shrl $2,%ecx | |
118 | rep ; stosl | |
484b90c4 VG |
119 | /* |
120 | * Copy bootup parameters out of the way. | |
121 | * Note: %esi still has the pointer to the real-mode data. | |
122 | * With the kexec as boot loader, parameter segment might be loaded beyond | |
123 | * kernel image and might not even be addressable by early boot page tables. | |
124 | * (kexec on panic case). Hence copy out the parameters before initializing | |
125 | * page tables. | |
126 | */ | |
551889a6 | 127 | movl $pa(boot_params),%edi |
484b90c4 VG |
128 | movl $(PARAM_SIZE/4),%ecx |
129 | cld | |
130 | rep | |
131 | movsl | |
551889a6 | 132 | movl pa(boot_params) + NEW_CL_POINTER,%esi |
484b90c4 | 133 | andl %esi,%esi |
b595076a | 134 | jz 1f # No command line |
551889a6 | 135 | movl $pa(boot_command_line),%edi |
484b90c4 VG |
136 | movl $(COMMAND_LINE_SIZE/4),%ecx |
137 | rep | |
138 | movsl | |
139 | 1: | |
1da177e4 | 140 | |
dc3119e7 | 141 | #ifdef CONFIG_OLPC |
fd699c76 AS |
142 | /* save OFW's pgdir table for later use when calling into OFW */ |
143 | movl %cr3, %eax | |
144 | movl %eax, pa(olpc_ofw_pgd) | |
145 | #endif | |
146 | ||
1da177e4 LT |
147 | /* |
148 | * Initialize page tables. This creates a PDE and a set of page | |
2bd2753f | 149 | * tables, which are located immediately beyond __brk_base. The variable |
ccf3fe02 | 150 | * _brk_end is set up to point to the first "safe" location. |
1da177e4 | 151 | * Mappings are created both at virtual address 0 (identity mapping) |
2bd2753f | 152 | * and PAGE_OFFSET for up to _end. |
1da177e4 | 153 | */ |
551889a6 IC |
154 | #ifdef CONFIG_X86_PAE |
155 | ||
156 | /* | |
b40827fa BP |
157 | * In PAE mode initial_page_table is statically defined to contain |
158 | * enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3 | |
159 | * entries). The identity mapping is handled by pointing two PGD entries | |
160 | * to the first kernel PMD. | |
551889a6 | 161 | * |
b40827fa | 162 | * Note the upper half of each PMD or PTE are always zero at this stage. |
551889a6 IC |
163 | */ |
164 | ||
86b2b70e | 165 | #define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */ |
551889a6 IC |
166 | |
167 | xorl %ebx,%ebx /* %ebx is kept at zero */ | |
168 | ||
ccf3fe02 | 169 | movl $pa(__brk_base), %edi |
b40827fa | 170 | movl $pa(initial_pg_pmd), %edx |
b2bc2731 | 171 | movl $PTE_IDENT_ATTR, %eax |
551889a6 | 172 | 10: |
b2bc2731 | 173 | leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */ |
551889a6 IC |
174 | movl %ecx,(%edx) /* Store PMD entry */ |
175 | /* Upper half already zero */ | |
176 | addl $8,%edx | |
177 | movl $512,%ecx | |
178 | 11: | |
179 | stosl | |
180 | xchgl %eax,%ebx | |
181 | stosl | |
182 | xchgl %eax,%ebx | |
183 | addl $0x1000,%eax | |
184 | loop 11b | |
185 | ||
186 | /* | |
c090f532 | 187 | * End condition: we must map up to the end + MAPPING_BEYOND_END. |
551889a6 | 188 | */ |
c090f532 | 189 | movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp |
551889a6 IC |
190 | cmpl %ebp,%eax |
191 | jb 10b | |
192 | 1: | |
ccf3fe02 JF |
193 | addl $__PAGE_OFFSET, %edi |
194 | movl %edi, pa(_brk_end) | |
6af61a76 YL |
195 | shrl $12, %eax |
196 | movl %eax, pa(max_pfn_mapped) | |
551889a6 IC |
197 | |
198 | /* Do early initialization of the fixmap area */ | |
b40827fa BP |
199 | movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax |
200 | movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8) | |
551889a6 IC |
201 | #else /* Not PAE */ |
202 | ||
203 | page_pde_offset = (__PAGE_OFFSET >> 20); | |
204 | ||
ccf3fe02 | 205 | movl $pa(__brk_base), %edi |
b40827fa | 206 | movl $pa(initial_page_table), %edx |
b2bc2731 | 207 | movl $PTE_IDENT_ATTR, %eax |
1da177e4 | 208 | 10: |
b2bc2731 | 209 | leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */ |
1da177e4 LT |
210 | movl %ecx,(%edx) /* Store identity PDE entry */ |
211 | movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */ | |
212 | addl $4,%edx | |
213 | movl $1024, %ecx | |
214 | 11: | |
215 | stosl | |
216 | addl $0x1000,%eax | |
217 | loop 11b | |
551889a6 | 218 | /* |
c090f532 | 219 | * End condition: we must map up to the end + MAPPING_BEYOND_END. |
551889a6 | 220 | */ |
c090f532 | 221 | movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp |
1da177e4 LT |
222 | cmpl %ebp,%eax |
223 | jb 10b | |
ccf3fe02 JF |
224 | addl $__PAGE_OFFSET, %edi |
225 | movl %edi, pa(_brk_end) | |
6af61a76 YL |
226 | shrl $12, %eax |
227 | movl %eax, pa(max_pfn_mapped) | |
17d57a92 | 228 | |
551889a6 | 229 | /* Do early initialization of the fixmap area */ |
b40827fa BP |
230 | movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax |
231 | movl %eax,pa(initial_page_table+0xffc) | |
551889a6 | 232 | #endif |
d50d8fe1 RR |
233 | |
234 | #ifdef CONFIG_PARAVIRT | |
235 | /* This is can only trip for a broken bootloader... */ | |
236 | cmpw $0x207, pa(boot_params + BP_version) | |
237 | jb default_entry | |
238 | ||
239 | /* Paravirt-compatible boot parameters. Look to see what architecture | |
240 | we're booting under. */ | |
241 | movl pa(boot_params + BP_hardware_subarch), %eax | |
242 | cmpl $num_subarch_entries, %eax | |
243 | jae bad_subarch | |
244 | ||
245 | movl pa(subarch_entries)(,%eax,4), %eax | |
246 | subl $__PAGE_OFFSET, %eax | |
247 | jmp *%eax | |
248 | ||
249 | bad_subarch: | |
250 | WEAK(lguest_entry) | |
251 | WEAK(xen_entry) | |
252 | /* Unknown implementation; there's really | |
253 | nothing we can do at this point. */ | |
254 | ud2a | |
255 | ||
256 | __INITDATA | |
257 | ||
258 | subarch_entries: | |
259 | .long default_entry /* normal x86/PC */ | |
260 | .long lguest_entry /* lguest hypervisor */ | |
261 | .long xen_entry /* Xen hypervisor */ | |
262 | .long default_entry /* Moorestown MID */ | |
263 | num_subarch_entries = (. - subarch_entries) / 4 | |
264 | .previous | |
265 | #else | |
266 | jmp default_entry | |
267 | #endif /* CONFIG_PARAVIRT */ | |
268 | ||
1da177e4 LT |
269 | /* |
270 | * Non-boot CPU entry point; entered from trampoline.S | |
271 | * We can't lgdt here, because lgdt itself uses a data segment, but | |
52de74dd | 272 | * we know the trampoline has already loaded the boot_gdt for us. |
f8657e1b VG |
273 | * |
274 | * If cpu hotplug is not supported then this code can go in init section | |
275 | * which will be freed later | |
1da177e4 | 276 | */ |
78b89ecd | 277 | __CPUINIT |
1da177e4 LT |
278 | ENTRY(startup_32_smp) |
279 | cld | |
280 | movl $(__BOOT_DS),%eax | |
281 | movl %eax,%ds | |
282 | movl %eax,%es | |
283 | movl %eax,%fs | |
284 | movl %eax,%gs | |
11d4c3f9 PA |
285 | movl pa(stack_start),%ecx |
286 | movl %eax,%ss | |
287 | leal -__PAGE_OFFSET(%ecx),%esp | |
48927bbb | 288 | |
d50d8fe1 | 289 | default_entry: |
1da177e4 LT |
290 | /* |
291 | * New page tables may be in 4Mbyte page mode and may | |
292 | * be using the global pages. | |
293 | * | |
294 | * NOTE! If we are on a 486 we may have no cr4 at all! | |
6662c34f PA |
295 | * Specifically, cr4 exists if and only if CPUID exists |
296 | * and has flags other than the FPU flag set. | |
1da177e4 | 297 | */ |
5a5a51db PA |
298 | movl $X86_EFLAGS_ID,%ecx |
299 | pushl %ecx | |
300 | popfl | |
301 | pushfl | |
302 | popl %eax | |
303 | pushl $0 | |
304 | popfl | |
305 | pushfl | |
306 | popl %edx | |
307 | xorl %edx,%eax | |
308 | testl %ecx,%eax | |
309 | jz 6f # No ID flag = no CPUID = no CR4 | |
310 | ||
6662c34f PA |
311 | movl $1,%eax |
312 | cpuid | |
313 | andl $~1,%edx # Ignore CPUID.FPU | |
314 | jz 6f # No flags or only CPUID.FPU = no CR4 | |
315 | ||
5a5a51db | 316 | movl pa(mmu_cr4_features),%eax |
1da177e4 LT |
317 | movl %eax,%cr4 |
318 | ||
8a50e513 PA |
319 | testb $X86_CR4_PAE, %al # check if PAE is enabled |
320 | jz 6f | |
1da177e4 LT |
321 | |
322 | /* Check if extended functions are implemented */ | |
323 | movl $0x80000000, %eax | |
324 | cpuid | |
8a50e513 PA |
325 | /* Value must be in the range 0x80000001 to 0x8000ffff */ |
326 | subl $0x80000001, %eax | |
327 | cmpl $(0x8000ffff-0x80000001), %eax | |
328 | ja 6f | |
ebba638a KC |
329 | |
330 | /* Clear bogus XD_DISABLE bits */ | |
331 | call verify_cpu | |
332 | ||
1da177e4 LT |
333 | mov $0x80000001, %eax |
334 | cpuid | |
335 | /* Execute Disable bit supported? */ | |
8a50e513 | 336 | btl $(X86_FEATURE_NX & 31), %edx |
1da177e4 LT |
337 | jnc 6f |
338 | ||
339 | /* Setup EFER (Extended Feature Enable Register) */ | |
8a50e513 | 340 | movl $MSR_EFER, %ecx |
1da177e4 LT |
341 | rdmsr |
342 | ||
8a50e513 | 343 | btsl $_EFER_NX, %eax |
1da177e4 LT |
344 | /* Make changes effective */ |
345 | wrmsr | |
346 | ||
347 | 6: | |
1da177e4 LT |
348 | |
349 | /* | |
350 | * Enable paging | |
351 | */ | |
b40827fa | 352 | movl $pa(initial_page_table), %eax |
1da177e4 LT |
353 | movl %eax,%cr3 /* set the page table pointer.. */ |
354 | movl %cr0,%eax | |
551889a6 | 355 | orl $X86_CR0_PG,%eax |
1da177e4 LT |
356 | movl %eax,%cr0 /* ..and set paging (PG) bit */ |
357 | ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */ | |
358 | 1: | |
11d4c3f9 PA |
359 | /* Shift the stack pointer to a virtual address */ |
360 | addl $__PAGE_OFFSET, %esp | |
1da177e4 LT |
361 | |
362 | /* | |
363 | * Initialize eflags. Some BIOS's leave bits like NT set. This would | |
364 | * confuse the debugger if this code is traced. | |
365 | * XXX - best to initialize before switching to protected mode. | |
366 | */ | |
367 | pushl $0 | |
368 | popfl | |
369 | ||
1da177e4 LT |
370 | /* |
371 | * start system 32-bit setup. We need to re-do some of the things done | |
372 | * in 16-bit mode for the "real" operations. | |
373 | */ | |
4c5023a3 PA |
374 | movl setup_once_ref,%eax |
375 | andl %eax,%eax | |
376 | jz 1f # Did we do this already? | |
377 | call *%eax | |
378 | 1: | |
379 | ||
1da177e4 LT |
380 | /* check if it is 486 or 386. */ |
381 | /* | |
382 | * XXX - this does a lot of unnecessary setup. Alignment checks don't | |
383 | * apply at our cpl of 0 and the stack ought to be aligned already, and | |
384 | * we don't need to preserve eflags. | |
385 | */ | |
4c5023a3 | 386 | movl $-1,X86_CPUID # -1 for no CPUID initially |
1da177e4 LT |
387 | movb $3,X86 # at least 386 |
388 | pushfl # push EFLAGS | |
389 | popl %eax # get EFLAGS | |
390 | movl %eax,%ecx # save original EFLAGS | |
391 | xorl $0x240000,%eax # flip AC and ID bits in EFLAGS | |
392 | pushl %eax # copy to EFLAGS | |
393 | popfl # set EFLAGS | |
394 | pushfl # get new EFLAGS | |
395 | popl %eax # put it in eax | |
396 | xorl %ecx,%eax # change in flags | |
397 | pushl %ecx # restore original EFLAGS | |
398 | popfl | |
399 | testl $0x40000,%eax # check if AC bit changed | |
400 | je is386 | |
401 | ||
402 | movb $4,X86 # at least 486 | |
403 | testl $0x200000,%eax # check if ID bit changed | |
404 | je is486 | |
405 | ||
406 | /* get vendor info */ | |
407 | xorl %eax,%eax # call CPUID with 0 -> return vendor ID | |
408 | cpuid | |
409 | movl %eax,X86_CPUID # save CPUID level | |
410 | movl %ebx,X86_VENDOR_ID # lo 4 chars | |
411 | movl %edx,X86_VENDOR_ID+4 # next 4 chars | |
412 | movl %ecx,X86_VENDOR_ID+8 # last 4 chars | |
413 | ||
414 | orl %eax,%eax # do we have processor info as well? | |
415 | je is486 | |
416 | ||
417 | movl $1,%eax # Use the CPUID instruction to get CPU type | |
418 | cpuid | |
419 | movb %al,%cl # save reg for future use | |
420 | andb $0x0f,%ah # mask processor family | |
421 | movb %ah,X86 | |
422 | andb $0xf0,%al # mask model | |
423 | shrb $4,%al | |
424 | movb %al,X86_MODEL | |
425 | andb $0x0f,%cl # mask mask revision | |
426 | movb %cl,X86_MASK | |
427 | movl %edx,X86_CAPABILITY | |
428 | ||
429 | is486: movl $0x50022,%ecx # set AM, WP, NE and MP | |
430 | jmp 2f | |
431 | ||
432 | is386: movl $2,%ecx # set MP | |
433 | 2: movl %cr0,%eax | |
434 | andl $0x80000011,%eax # Save PG,PE,ET | |
435 | orl %ecx,%eax | |
436 | movl %eax,%cr0 | |
437 | ||
438 | call check_x87 | |
2a57ff1a | 439 | lgdt early_gdt_descr |
1da177e4 LT |
440 | lidt idt_descr |
441 | ljmp $(__KERNEL_CS),$1f | |
442 | 1: movl $(__KERNEL_DS),%eax # reload all the segment registers | |
443 | movl %eax,%ss # after changing gdt. | |
444 | ||
445 | movl $(__USER_DS),%eax # DS/ES contains default USER segment | |
446 | movl %eax,%ds | |
447 | movl %eax,%es | |
448 | ||
0dd76d73 BG |
449 | movl $(__KERNEL_PERCPU), %eax |
450 | movl %eax,%fs # set this cpu's percpu | |
451 | ||
60a5317f | 452 | movl $(__KERNEL_STACK_CANARY),%eax |
464d1a78 | 453 | movl %eax,%gs |
60a5317f TH |
454 | |
455 | xorl %eax,%eax # Clear LDT | |
1da177e4 | 456 | lldt %ax |
f95d47ca | 457 | |
1da177e4 | 458 | cld # gcc2 wants the direction flag cleared at all times |
26fd5e08 | 459 | pushl $0 # fake return address for unwinder |
e3f77edf | 460 | jmp *(initial_code) |
1da177e4 LT |
461 | |
462 | /* | |
463 | * We depend on ET to be correct. This checks for 287/387. | |
464 | */ | |
465 | check_x87: | |
466 | movb $0,X86_HARD_MATH | |
467 | clts | |
468 | fninit | |
469 | fstsw %ax | |
470 | cmpb $0,%al | |
471 | je 1f | |
472 | movl %cr0,%eax /* no coprocessor: have to set bits */ | |
473 | xorl $4,%eax /* set EM */ | |
474 | movl %eax,%cr0 | |
475 | ret | |
476 | ALIGN | |
477 | 1: movb $1,X86_HARD_MATH | |
478 | .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */ | |
479 | ret | |
480 | ||
4c5023a3 PA |
481 | |
482 | #include "verify_cpu.S" | |
483 | ||
1da177e4 | 484 | /* |
4c5023a3 | 485 | * setup_once |
1da177e4 | 486 | * |
4c5023a3 | 487 | * The setup work we only want to run on the BSP. |
1da177e4 LT |
488 | * |
489 | * Warning: %esi is live across this function. | |
490 | */ | |
4c5023a3 PA |
491 | __INIT |
492 | setup_once: | |
493 | /* | |
494 | * Set up a idt with 256 entries pointing to ignore_int, | |
495 | * interrupt gates. It doesn't actually load idt - that needs | |
496 | * to be done on each CPU. Interrupts are enabled elsewhere, | |
497 | * when we can be relatively sure everything is ok. | |
498 | */ | |
1da177e4 | 499 | |
4c5023a3 PA |
500 | movl $idt_table,%edi |
501 | movl $early_idt_handlers,%eax | |
502 | movl $NUM_EXCEPTION_VECTORS,%ecx | |
503 | 1: | |
1da177e4 | 504 | movl %eax,(%edi) |
4c5023a3 PA |
505 | movl %eax,4(%edi) |
506 | /* interrupt gate, dpl=0, present */ | |
507 | movl $(0x8E000000 + __KERNEL_CS),2(%edi) | |
508 | addl $9,%eax | |
1da177e4 | 509 | addl $8,%edi |
4c5023a3 | 510 | loop 1b |
ec5c0926 | 511 | |
4c5023a3 PA |
512 | movl $256 - NUM_EXCEPTION_VECTORS,%ecx |
513 | movl $ignore_int,%edx | |
ec5c0926 | 514 | movl $(__KERNEL_CS << 16),%eax |
4c5023a3 | 515 | movw %dx,%ax /* selector = 0x0010 = cs */ |
ec5c0926 | 516 | movw $0x8E00,%dx /* interrupt gate - dpl=0, present */ |
4c5023a3 PA |
517 | 2: |
518 | movl %eax,(%edi) | |
519 | movl %edx,4(%edi) | |
520 | addl $8,%edi | |
521 | loop 2b | |
ec5c0926 | 522 | |
4c5023a3 PA |
523 | #ifdef CONFIG_CC_STACKPROTECTOR |
524 | /* | |
525 | * Configure the stack canary. The linker can't handle this by | |
526 | * relocation. Manually set base address in stack canary | |
527 | * segment descriptor. | |
528 | */ | |
529 | movl $gdt_page,%eax | |
530 | movl $stack_canary,%ecx | |
531 | movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax) | |
532 | shrl $16, %ecx | |
533 | movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax) | |
534 | movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax) | |
535 | #endif | |
ec5c0926 | 536 | |
4c5023a3 | 537 | andl $0,setup_once_ref /* Once is enough, thanks */ |
1da177e4 LT |
538 | ret |
539 | ||
4c5023a3 PA |
540 | ENTRY(early_idt_handlers) |
541 | # 36(%esp) %eflags | |
542 | # 32(%esp) %cs | |
543 | # 28(%esp) %eip | |
544 | # 24(%rsp) error code | |
545 | i = 0 | |
546 | .rept NUM_EXCEPTION_VECTORS | |
547 | .if (EXCEPTION_ERRCODE_MASK >> i) & 1 | |
548 | ASM_NOP2 | |
549 | .else | |
550 | pushl $0 # Dummy error code, to make stack frame uniform | |
551 | .endif | |
552 | pushl $i # 20(%esp) Vector number | |
553 | jmp early_idt_handler | |
554 | i = i + 1 | |
555 | .endr | |
556 | ENDPROC(early_idt_handlers) | |
557 | ||
558 | /* This is global to keep gas from relaxing the jumps */ | |
559 | ENTRY(early_idt_handler) | |
560 | cld | |
561 | cmpl $2,%ss:early_recursion_flag | |
562 | je hlt_loop | |
563 | incl %ss:early_recursion_flag | |
ec5c0926 | 564 | |
4c5023a3 PA |
565 | push %eax # 16(%esp) |
566 | push %ecx # 12(%esp) | |
567 | push %edx # 8(%esp) | |
568 | push %ds # 4(%esp) | |
569 | push %es # 0(%esp) | |
570 | movl $(__KERNEL_DS),%eax | |
571 | movl %eax,%ds | |
572 | movl %eax,%es | |
ec5c0926 | 573 | |
4c5023a3 PA |
574 | cmpl $(__KERNEL_CS),32(%esp) |
575 | jne 10f | |
ec5c0926 | 576 | |
4c5023a3 PA |
577 | leal 28(%esp),%eax # Pointer to %eip |
578 | call early_fixup_exception | |
579 | andl %eax,%eax | |
580 | jnz ex_entry /* found an exception entry */ | |
ec5c0926 | 581 | |
4c5023a3 | 582 | 10: |
ec5c0926 | 583 | #ifdef CONFIG_PRINTK |
4c5023a3 PA |
584 | xorl %eax,%eax |
585 | movw %ax,2(%esp) /* clean up the segment values on some cpus */ | |
586 | movw %ax,6(%esp) | |
587 | movw %ax,34(%esp) | |
588 | leal 40(%esp),%eax | |
589 | pushl %eax /* %esp before the exception */ | |
590 | pushl %ebx | |
591 | pushl %ebp | |
592 | pushl %esi | |
593 | pushl %edi | |
ec5c0926 CE |
594 | movl %cr2,%eax |
595 | pushl %eax | |
4c5023a3 | 596 | pushl (20+6*4)(%esp) /* trapno */ |
ec5c0926 | 597 | pushl $fault_msg |
ec5c0926 | 598 | call printk |
ec5c0926 | 599 | #endif |
94878efd | 600 | call dump_stack |
ec5c0926 CE |
601 | hlt_loop: |
602 | hlt | |
603 | jmp hlt_loop | |
604 | ||
4c5023a3 PA |
605 | ex_entry: |
606 | pop %es | |
607 | pop %ds | |
608 | pop %edx | |
609 | pop %ecx | |
610 | pop %eax | |
611 | addl $8,%esp /* drop vector number and error code */ | |
612 | decl %ss:early_recursion_flag | |
613 | iret | |
614 | ENDPROC(early_idt_handler) | |
615 | ||
1da177e4 LT |
616 | /* This is the default interrupt "handler" :-) */ |
617 | ALIGN | |
618 | ignore_int: | |
619 | cld | |
d59745ce | 620 | #ifdef CONFIG_PRINTK |
1da177e4 LT |
621 | pushl %eax |
622 | pushl %ecx | |
623 | pushl %edx | |
624 | pushl %es | |
625 | pushl %ds | |
626 | movl $(__KERNEL_DS),%eax | |
627 | movl %eax,%ds | |
628 | movl %eax,%es | |
ec5c0926 CE |
629 | cmpl $2,early_recursion_flag |
630 | je hlt_loop | |
631 | incl early_recursion_flag | |
1da177e4 LT |
632 | pushl 16(%esp) |
633 | pushl 24(%esp) | |
634 | pushl 32(%esp) | |
635 | pushl 40(%esp) | |
636 | pushl $int_msg | |
637 | call printk | |
d5e397cb IM |
638 | |
639 | call dump_stack | |
640 | ||
1da177e4 LT |
641 | addl $(5*4),%esp |
642 | popl %ds | |
643 | popl %es | |
644 | popl %edx | |
645 | popl %ecx | |
646 | popl %eax | |
d59745ce | 647 | #endif |
1da177e4 | 648 | iret |
4c5023a3 PA |
649 | ENDPROC(ignore_int) |
650 | __INITDATA | |
651 | .align 4 | |
652 | early_recursion_flag: | |
653 | .long 0 | |
1da177e4 | 654 | |
4c5023a3 PA |
655 | __REFDATA |
656 | .align 4 | |
583323b9 TG |
657 | ENTRY(initial_code) |
658 | .long i386_start_kernel | |
4c5023a3 PA |
659 | ENTRY(setup_once_ref) |
660 | .long setup_once | |
583323b9 | 661 | |
1da177e4 LT |
662 | /* |
663 | * BSS section | |
664 | */ | |
02b7da37 | 665 | __PAGE_ALIGNED_BSS |
7bf04be8 | 666 | .align PAGE_SIZE |
551889a6 | 667 | #ifdef CONFIG_X86_PAE |
d50d8fe1 | 668 | initial_pg_pmd: |
551889a6 IC |
669 | .fill 1024*KPMDS,4,0 |
670 | #else | |
b40827fa | 671 | ENTRY(initial_page_table) |
1da177e4 | 672 | .fill 1024,4,0 |
551889a6 | 673 | #endif |
d50d8fe1 | 674 | initial_pg_fixmap: |
b1c931e3 | 675 | .fill 1024,4,0 |
1da177e4 LT |
676 | ENTRY(empty_zero_page) |
677 | .fill 4096,1,0 | |
b40827fa BP |
678 | ENTRY(swapper_pg_dir) |
679 | .fill 1024,4,0 | |
2bd2753f | 680 | |
1da177e4 LT |
681 | /* |
682 | * This starts the data section. | |
683 | */ | |
551889a6 | 684 | #ifdef CONFIG_X86_PAE |
abe1ee3a | 685 | __PAGE_ALIGNED_DATA |
551889a6 | 686 | /* Page-aligned for the benefit of paravirt? */ |
7bf04be8 | 687 | .align PAGE_SIZE |
b40827fa BP |
688 | ENTRY(initial_page_table) |
689 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */ | |
551889a6 | 690 | # if KPMDS == 3 |
b40827fa BP |
691 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
692 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0 | |
693 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x2000),0 | |
551889a6 IC |
694 | # elif KPMDS == 2 |
695 | .long 0,0 | |
b40827fa BP |
696 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
697 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0 | |
551889a6 IC |
698 | # elif KPMDS == 1 |
699 | .long 0,0 | |
700 | .long 0,0 | |
b40827fa | 701 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
551889a6 IC |
702 | # else |
703 | # error "Kernel PMDs should be 1, 2 or 3" | |
704 | # endif | |
7bf04be8 | 705 | .align PAGE_SIZE /* needs to be page-sized too */ |
551889a6 IC |
706 | #endif |
707 | ||
1da177e4 | 708 | .data |
11d4c3f9 | 709 | .balign 4 |
1da177e4 LT |
710 | ENTRY(stack_start) |
711 | .long init_thread_union+THREAD_SIZE | |
1da177e4 | 712 | |
4c5023a3 | 713 | __INITRODATA |
1da177e4 | 714 | int_msg: |
d5e397cb | 715 | .asciz "Unknown interrupt or fault at: %p %p %p\n" |
1da177e4 | 716 | |
ec5c0926 | 717 | fault_msg: |
575ca735 VN |
718 | /* fault info: */ |
719 | .ascii "BUG: Int %d: CR2 %p\n" | |
4c5023a3 PA |
720 | /* regs pushed in early_idt_handler: */ |
721 | .ascii " EDI %p ESI %p EBP %p EBX %p\n" | |
722 | .ascii " ESP %p ES %p DS %p\n" | |
723 | .ascii " EDX %p ECX %p EAX %p\n" | |
575ca735 | 724 | /* fault frame: */ |
4c5023a3 | 725 | .ascii " vec %p err %p EIP %p CS %p flg %p\n" |
575ca735 VN |
726 | .ascii "Stack: %p %p %p %p %p %p %p %p\n" |
727 | .ascii " %p %p %p %p %p %p %p %p\n" | |
728 | .asciz " %p %p %p %p %p %p %p %p\n" | |
ec5c0926 | 729 | |
9702785a | 730 | #include "../../x86/xen/xen-head.S" |
5ead97c8 | 731 | |
1da177e4 LT |
732 | /* |
733 | * The IDT and GDT 'descriptors' are a strange 48-bit object | |
734 | * only used by the lidt and lgdt instructions. They are not | |
735 | * like usual segment descriptors - they consist of a 16-bit | |
736 | * segment size, and 32-bit linear address value: | |
737 | */ | |
738 | ||
4c5023a3 | 739 | .data |
1da177e4 LT |
740 | .globl boot_gdt_descr |
741 | .globl idt_descr | |
1da177e4 LT |
742 | |
743 | ALIGN | |
744 | # early boot GDT descriptor (must use 1:1 address mapping) | |
745 | .word 0 # 32 bit align gdt_desc.address | |
746 | boot_gdt_descr: | |
747 | .word __BOOT_DS+7 | |
52de74dd | 748 | .long boot_gdt - __PAGE_OFFSET |
1da177e4 LT |
749 | |
750 | .word 0 # 32-bit align idt_desc.address | |
751 | idt_descr: | |
752 | .word IDT_ENTRIES*8-1 # idt contains 256 entries | |
753 | .long idt_table | |
754 | ||
755 | # boot GDT descriptor (later on used by CPU#0): | |
756 | .word 0 # 32 bit align gdt_desc.address | |
2a57ff1a | 757 | ENTRY(early_gdt_descr) |
1da177e4 | 758 | .word GDT_ENTRIES*8-1 |
dd17c8f7 | 759 | .long gdt_page /* Overwritten for secondary CPUs */ |
1da177e4 | 760 | |
1da177e4 | 761 | /* |
52de74dd | 762 | * The boot_gdt must mirror the equivalent in setup.S and is |
1da177e4 LT |
763 | * used only for booting. |
764 | */ | |
765 | .align L1_CACHE_BYTES | |
52de74dd | 766 | ENTRY(boot_gdt) |
1da177e4 LT |
767 | .fill GDT_ENTRY_BOOT_CS,8,0 |
768 | .quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */ | |
769 | .quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */ |