]>
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 | ||
3e2a0cc3 FY |
269 | #ifdef CONFIG_HOTPLUG_CPU |
270 | /* | |
271 | * Boot CPU0 entry point. It's called from play_dead(). Everything has been set | |
272 | * up already except stack. We just set up stack here. Then call | |
273 | * start_secondary(). | |
274 | */ | |
275 | ENTRY(start_cpu0) | |
276 | movl stack_start, %ecx | |
277 | movl %ecx, %esp | |
278 | jmp *(initial_code) | |
279 | ENDPROC(start_cpu0) | |
280 | #endif | |
281 | ||
1da177e4 LT |
282 | /* |
283 | * Non-boot CPU entry point; entered from trampoline.S | |
284 | * We can't lgdt here, because lgdt itself uses a data segment, but | |
52de74dd | 285 | * we know the trampoline has already loaded the boot_gdt for us. |
f8657e1b VG |
286 | * |
287 | * If cpu hotplug is not supported then this code can go in init section | |
288 | * which will be freed later | |
1da177e4 | 289 | */ |
78b89ecd | 290 | __CPUINIT |
1da177e4 LT |
291 | ENTRY(startup_32_smp) |
292 | cld | |
293 | movl $(__BOOT_DS),%eax | |
294 | movl %eax,%ds | |
295 | movl %eax,%es | |
296 | movl %eax,%fs | |
297 | movl %eax,%gs | |
11d4c3f9 PA |
298 | movl pa(stack_start),%ecx |
299 | movl %eax,%ss | |
300 | leal -__PAGE_OFFSET(%ecx),%esp | |
48927bbb | 301 | |
d50d8fe1 | 302 | default_entry: |
021ef050 PA |
303 | #define CR0_STATE (X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | \ |
304 | X86_CR0_NE | X86_CR0_WP | X86_CR0_AM | \ | |
305 | X86_CR0_PG) | |
306 | movl $(CR0_STATE & ~X86_CR0_PG),%eax | |
307 | movl %eax,%cr0 | |
308 | ||
1da177e4 | 309 | /* |
9efb58de BP |
310 | * We want to start out with EFLAGS unambiguously cleared. Some BIOSes leave |
311 | * bits like NT set. This would confuse the debugger if this code is traced. So | |
312 | * initialize them properly now before switching to protected mode. That means | |
313 | * DF in particular (even though we have cleared it earlier after copying the | |
314 | * command line) because GCC expects it. | |
315 | */ | |
316 | pushl $0 | |
317 | popfl | |
318 | ||
319 | /* | |
320 | * New page tables may be in 4Mbyte page mode and may be using the global pages. | |
1da177e4 | 321 | * |
9efb58de BP |
322 | * NOTE! If we are on a 486 we may have no cr4 at all! Specifically, cr4 exists |
323 | * if and only if CPUID exists and has flags other than the FPU flag set. | |
1da177e4 | 324 | */ |
9efb58de | 325 | movl $-1,pa(X86_CPUID) # preset CPUID level |
5a5a51db PA |
326 | movl $X86_EFLAGS_ID,%ecx |
327 | pushl %ecx | |
9efb58de | 328 | popfl # set EFLAGS=ID |
5a5a51db | 329 | pushfl |
9efb58de BP |
330 | popl %eax # get EFLAGS |
331 | testl $X86_EFLAGS_ID,%eax # did EFLAGS.ID remained set? | |
332 | jz 6f # hw disallowed setting of ID bit | |
333 | # which means no CPUID and no CR4 | |
334 | ||
335 | xorl %eax,%eax | |
336 | cpuid | |
337 | movl %eax,pa(X86_CPUID) # save largest std CPUID function | |
5a5a51db | 338 | |
6662c34f PA |
339 | movl $1,%eax |
340 | cpuid | |
9efb58de BP |
341 | andl $~1,%edx # Ignore CPUID.FPU |
342 | jz 6f # No flags or only CPUID.FPU = no CR4 | |
6662c34f | 343 | |
5a5a51db | 344 | movl pa(mmu_cr4_features),%eax |
1da177e4 LT |
345 | movl %eax,%cr4 |
346 | ||
8a50e513 PA |
347 | testb $X86_CR4_PAE, %al # check if PAE is enabled |
348 | jz 6f | |
1da177e4 LT |
349 | |
350 | /* Check if extended functions are implemented */ | |
351 | movl $0x80000000, %eax | |
352 | cpuid | |
8a50e513 PA |
353 | /* Value must be in the range 0x80000001 to 0x8000ffff */ |
354 | subl $0x80000001, %eax | |
355 | cmpl $(0x8000ffff-0x80000001), %eax | |
356 | ja 6f | |
ebba638a KC |
357 | |
358 | /* Clear bogus XD_DISABLE bits */ | |
359 | call verify_cpu | |
360 | ||
1da177e4 LT |
361 | mov $0x80000001, %eax |
362 | cpuid | |
363 | /* Execute Disable bit supported? */ | |
8a50e513 | 364 | btl $(X86_FEATURE_NX & 31), %edx |
1da177e4 LT |
365 | jnc 6f |
366 | ||
367 | /* Setup EFER (Extended Feature Enable Register) */ | |
8a50e513 | 368 | movl $MSR_EFER, %ecx |
1da177e4 LT |
369 | rdmsr |
370 | ||
8a50e513 | 371 | btsl $_EFER_NX, %eax |
1da177e4 LT |
372 | /* Make changes effective */ |
373 | wrmsr | |
374 | ||
375 | 6: | |
1da177e4 LT |
376 | |
377 | /* | |
378 | * Enable paging | |
379 | */ | |
b40827fa | 380 | movl $pa(initial_page_table), %eax |
1da177e4 | 381 | movl %eax,%cr3 /* set the page table pointer.. */ |
021ef050 | 382 | movl $CR0_STATE,%eax |
1da177e4 LT |
383 | movl %eax,%cr0 /* ..and set paging (PG) bit */ |
384 | ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */ | |
385 | 1: | |
11d4c3f9 PA |
386 | /* Shift the stack pointer to a virtual address */ |
387 | addl $__PAGE_OFFSET, %esp | |
1da177e4 | 388 | |
1da177e4 LT |
389 | /* |
390 | * start system 32-bit setup. We need to re-do some of the things done | |
391 | * in 16-bit mode for the "real" operations. | |
392 | */ | |
4c5023a3 PA |
393 | movl setup_once_ref,%eax |
394 | andl %eax,%eax | |
395 | jz 1f # Did we do this already? | |
396 | call *%eax | |
397 | 1: | |
166df91d | 398 | |
1da177e4 | 399 | /* |
166df91d | 400 | * Check if it is 486 |
1da177e4 | 401 | */ |
c3a22a26 | 402 | cmpl $-1,X86_CPUID |
1da177e4 LT |
403 | je is486 |
404 | ||
405 | /* get vendor info */ | |
406 | xorl %eax,%eax # call CPUID with 0 -> return vendor ID | |
407 | cpuid | |
408 | movl %eax,X86_CPUID # save CPUID level | |
409 | movl %ebx,X86_VENDOR_ID # lo 4 chars | |
410 | movl %edx,X86_VENDOR_ID+4 # next 4 chars | |
411 | movl %ecx,X86_VENDOR_ID+8 # last 4 chars | |
412 | ||
413 | orl %eax,%eax # do we have processor info as well? | |
414 | je is486 | |
415 | ||
416 | movl $1,%eax # Use the CPUID instruction to get CPU type | |
417 | cpuid | |
418 | movb %al,%cl # save reg for future use | |
419 | andb $0x0f,%ah # mask processor family | |
420 | movb %ah,X86 | |
421 | andb $0xf0,%al # mask model | |
422 | shrb $4,%al | |
423 | movb %al,X86_MODEL | |
424 | andb $0x0f,%cl # mask mask revision | |
425 | movb %cl,X86_MASK | |
426 | movl %edx,X86_CAPABILITY | |
427 | ||
c3a22a26 BP |
428 | is486: |
429 | movb $4,X86 | |
430 | movl $0x50022,%ecx # set AM, WP, NE and MP | |
166df91d | 431 | movl %cr0,%eax |
1da177e4 LT |
432 | andl $0x80000011,%eax # Save PG,PE,ET |
433 | orl %ecx,%eax | |
434 | movl %eax,%cr0 | |
435 | ||
436 | call check_x87 | |
2a57ff1a | 437 | lgdt early_gdt_descr |
1da177e4 LT |
438 | lidt idt_descr |
439 | ljmp $(__KERNEL_CS),$1f | |
440 | 1: movl $(__KERNEL_DS),%eax # reload all the segment registers | |
441 | movl %eax,%ss # after changing gdt. | |
442 | ||
443 | movl $(__USER_DS),%eax # DS/ES contains default USER segment | |
444 | movl %eax,%ds | |
445 | movl %eax,%es | |
446 | ||
0dd76d73 BG |
447 | movl $(__KERNEL_PERCPU), %eax |
448 | movl %eax,%fs # set this cpu's percpu | |
449 | ||
60a5317f | 450 | movl $(__KERNEL_STACK_CANARY),%eax |
464d1a78 | 451 | movl %eax,%gs |
60a5317f TH |
452 | |
453 | xorl %eax,%eax # Clear LDT | |
1da177e4 | 454 | lldt %ax |
f95d47ca | 455 | |
26fd5e08 | 456 | pushl $0 # fake return address for unwinder |
e3f77edf | 457 | jmp *(initial_code) |
1da177e4 LT |
458 | |
459 | /* | |
460 | * We depend on ET to be correct. This checks for 287/387. | |
461 | */ | |
462 | check_x87: | |
463 | movb $0,X86_HARD_MATH | |
464 | clts | |
465 | fninit | |
466 | fstsw %ax | |
467 | cmpb $0,%al | |
468 | je 1f | |
469 | movl %cr0,%eax /* no coprocessor: have to set bits */ | |
470 | xorl $4,%eax /* set EM */ | |
471 | movl %eax,%cr0 | |
472 | ret | |
473 | ALIGN | |
474 | 1: movb $1,X86_HARD_MATH | |
475 | .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */ | |
476 | ret | |
477 | ||
4c5023a3 PA |
478 | |
479 | #include "verify_cpu.S" | |
480 | ||
1da177e4 | 481 | /* |
4c5023a3 | 482 | * setup_once |
1da177e4 | 483 | * |
4c5023a3 | 484 | * The setup work we only want to run on the BSP. |
1da177e4 LT |
485 | * |
486 | * Warning: %esi is live across this function. | |
487 | */ | |
4c5023a3 PA |
488 | __INIT |
489 | setup_once: | |
490 | /* | |
491 | * Set up a idt with 256 entries pointing to ignore_int, | |
492 | * interrupt gates. It doesn't actually load idt - that needs | |
493 | * to be done on each CPU. Interrupts are enabled elsewhere, | |
494 | * when we can be relatively sure everything is ok. | |
495 | */ | |
1da177e4 | 496 | |
4c5023a3 PA |
497 | movl $idt_table,%edi |
498 | movl $early_idt_handlers,%eax | |
499 | movl $NUM_EXCEPTION_VECTORS,%ecx | |
500 | 1: | |
1da177e4 | 501 | movl %eax,(%edi) |
4c5023a3 PA |
502 | movl %eax,4(%edi) |
503 | /* interrupt gate, dpl=0, present */ | |
504 | movl $(0x8E000000 + __KERNEL_CS),2(%edi) | |
505 | addl $9,%eax | |
1da177e4 | 506 | addl $8,%edi |
4c5023a3 | 507 | loop 1b |
ec5c0926 | 508 | |
4c5023a3 PA |
509 | movl $256 - NUM_EXCEPTION_VECTORS,%ecx |
510 | movl $ignore_int,%edx | |
ec5c0926 | 511 | movl $(__KERNEL_CS << 16),%eax |
4c5023a3 | 512 | movw %dx,%ax /* selector = 0x0010 = cs */ |
ec5c0926 | 513 | movw $0x8E00,%dx /* interrupt gate - dpl=0, present */ |
4c5023a3 PA |
514 | 2: |
515 | movl %eax,(%edi) | |
516 | movl %edx,4(%edi) | |
517 | addl $8,%edi | |
518 | loop 2b | |
ec5c0926 | 519 | |
4c5023a3 PA |
520 | #ifdef CONFIG_CC_STACKPROTECTOR |
521 | /* | |
522 | * Configure the stack canary. The linker can't handle this by | |
523 | * relocation. Manually set base address in stack canary | |
524 | * segment descriptor. | |
525 | */ | |
526 | movl $gdt_page,%eax | |
527 | movl $stack_canary,%ecx | |
528 | movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax) | |
529 | shrl $16, %ecx | |
530 | movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax) | |
531 | movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax) | |
532 | #endif | |
ec5c0926 | 533 | |
4c5023a3 | 534 | andl $0,setup_once_ref /* Once is enough, thanks */ |
1da177e4 LT |
535 | ret |
536 | ||
4c5023a3 PA |
537 | ENTRY(early_idt_handlers) |
538 | # 36(%esp) %eflags | |
539 | # 32(%esp) %cs | |
540 | # 28(%esp) %eip | |
541 | # 24(%rsp) error code | |
542 | i = 0 | |
543 | .rept NUM_EXCEPTION_VECTORS | |
544 | .if (EXCEPTION_ERRCODE_MASK >> i) & 1 | |
545 | ASM_NOP2 | |
546 | .else | |
547 | pushl $0 # Dummy error code, to make stack frame uniform | |
548 | .endif | |
549 | pushl $i # 20(%esp) Vector number | |
550 | jmp early_idt_handler | |
551 | i = i + 1 | |
552 | .endr | |
553 | ENDPROC(early_idt_handlers) | |
554 | ||
555 | /* This is global to keep gas from relaxing the jumps */ | |
556 | ENTRY(early_idt_handler) | |
557 | cld | |
558 | cmpl $2,%ss:early_recursion_flag | |
559 | je hlt_loop | |
560 | incl %ss:early_recursion_flag | |
ec5c0926 | 561 | |
4c5023a3 PA |
562 | push %eax # 16(%esp) |
563 | push %ecx # 12(%esp) | |
564 | push %edx # 8(%esp) | |
565 | push %ds # 4(%esp) | |
566 | push %es # 0(%esp) | |
567 | movl $(__KERNEL_DS),%eax | |
568 | movl %eax,%ds | |
569 | movl %eax,%es | |
ec5c0926 | 570 | |
4c5023a3 PA |
571 | cmpl $(__KERNEL_CS),32(%esp) |
572 | jne 10f | |
ec5c0926 | 573 | |
4c5023a3 PA |
574 | leal 28(%esp),%eax # Pointer to %eip |
575 | call early_fixup_exception | |
576 | andl %eax,%eax | |
577 | jnz ex_entry /* found an exception entry */ | |
ec5c0926 | 578 | |
4c5023a3 | 579 | 10: |
ec5c0926 | 580 | #ifdef CONFIG_PRINTK |
4c5023a3 PA |
581 | xorl %eax,%eax |
582 | movw %ax,2(%esp) /* clean up the segment values on some cpus */ | |
583 | movw %ax,6(%esp) | |
584 | movw %ax,34(%esp) | |
585 | leal 40(%esp),%eax | |
586 | pushl %eax /* %esp before the exception */ | |
587 | pushl %ebx | |
588 | pushl %ebp | |
589 | pushl %esi | |
590 | pushl %edi | |
ec5c0926 CE |
591 | movl %cr2,%eax |
592 | pushl %eax | |
4c5023a3 | 593 | pushl (20+6*4)(%esp) /* trapno */ |
ec5c0926 | 594 | pushl $fault_msg |
ec5c0926 | 595 | call printk |
ec5c0926 | 596 | #endif |
94878efd | 597 | call dump_stack |
ec5c0926 CE |
598 | hlt_loop: |
599 | hlt | |
600 | jmp hlt_loop | |
601 | ||
4c5023a3 PA |
602 | ex_entry: |
603 | pop %es | |
604 | pop %ds | |
605 | pop %edx | |
606 | pop %ecx | |
607 | pop %eax | |
608 | addl $8,%esp /* drop vector number and error code */ | |
609 | decl %ss:early_recursion_flag | |
610 | iret | |
611 | ENDPROC(early_idt_handler) | |
612 | ||
1da177e4 LT |
613 | /* This is the default interrupt "handler" :-) */ |
614 | ALIGN | |
615 | ignore_int: | |
616 | cld | |
d59745ce | 617 | #ifdef CONFIG_PRINTK |
1da177e4 LT |
618 | pushl %eax |
619 | pushl %ecx | |
620 | pushl %edx | |
621 | pushl %es | |
622 | pushl %ds | |
623 | movl $(__KERNEL_DS),%eax | |
624 | movl %eax,%ds | |
625 | movl %eax,%es | |
ec5c0926 CE |
626 | cmpl $2,early_recursion_flag |
627 | je hlt_loop | |
628 | incl early_recursion_flag | |
1da177e4 LT |
629 | pushl 16(%esp) |
630 | pushl 24(%esp) | |
631 | pushl 32(%esp) | |
632 | pushl 40(%esp) | |
633 | pushl $int_msg | |
634 | call printk | |
d5e397cb IM |
635 | |
636 | call dump_stack | |
637 | ||
1da177e4 LT |
638 | addl $(5*4),%esp |
639 | popl %ds | |
640 | popl %es | |
641 | popl %edx | |
642 | popl %ecx | |
643 | popl %eax | |
d59745ce | 644 | #endif |
1da177e4 | 645 | iret |
4c5023a3 PA |
646 | ENDPROC(ignore_int) |
647 | __INITDATA | |
648 | .align 4 | |
649 | early_recursion_flag: | |
650 | .long 0 | |
1da177e4 | 651 | |
4c5023a3 PA |
652 | __REFDATA |
653 | .align 4 | |
583323b9 TG |
654 | ENTRY(initial_code) |
655 | .long i386_start_kernel | |
4c5023a3 PA |
656 | ENTRY(setup_once_ref) |
657 | .long setup_once | |
583323b9 | 658 | |
1da177e4 LT |
659 | /* |
660 | * BSS section | |
661 | */ | |
02b7da37 | 662 | __PAGE_ALIGNED_BSS |
7bf04be8 | 663 | .align PAGE_SIZE |
551889a6 | 664 | #ifdef CONFIG_X86_PAE |
d50d8fe1 | 665 | initial_pg_pmd: |
551889a6 IC |
666 | .fill 1024*KPMDS,4,0 |
667 | #else | |
b40827fa | 668 | ENTRY(initial_page_table) |
1da177e4 | 669 | .fill 1024,4,0 |
551889a6 | 670 | #endif |
d50d8fe1 | 671 | initial_pg_fixmap: |
b1c931e3 | 672 | .fill 1024,4,0 |
1da177e4 LT |
673 | ENTRY(empty_zero_page) |
674 | .fill 4096,1,0 | |
b40827fa BP |
675 | ENTRY(swapper_pg_dir) |
676 | .fill 1024,4,0 | |
2bd2753f | 677 | |
1da177e4 LT |
678 | /* |
679 | * This starts the data section. | |
680 | */ | |
551889a6 | 681 | #ifdef CONFIG_X86_PAE |
abe1ee3a | 682 | __PAGE_ALIGNED_DATA |
551889a6 | 683 | /* Page-aligned for the benefit of paravirt? */ |
7bf04be8 | 684 | .align PAGE_SIZE |
b40827fa BP |
685 | ENTRY(initial_page_table) |
686 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */ | |
551889a6 | 687 | # if KPMDS == 3 |
b40827fa BP |
688 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
689 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0 | |
690 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x2000),0 | |
551889a6 IC |
691 | # elif KPMDS == 2 |
692 | .long 0,0 | |
b40827fa BP |
693 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
694 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0 | |
551889a6 IC |
695 | # elif KPMDS == 1 |
696 | .long 0,0 | |
697 | .long 0,0 | |
b40827fa | 698 | .long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 |
551889a6 IC |
699 | # else |
700 | # error "Kernel PMDs should be 1, 2 or 3" | |
701 | # endif | |
7bf04be8 | 702 | .align PAGE_SIZE /* needs to be page-sized too */ |
551889a6 IC |
703 | #endif |
704 | ||
1da177e4 | 705 | .data |
11d4c3f9 | 706 | .balign 4 |
1da177e4 LT |
707 | ENTRY(stack_start) |
708 | .long init_thread_union+THREAD_SIZE | |
1da177e4 | 709 | |
4c5023a3 | 710 | __INITRODATA |
1da177e4 | 711 | int_msg: |
d5e397cb | 712 | .asciz "Unknown interrupt or fault at: %p %p %p\n" |
1da177e4 | 713 | |
ec5c0926 | 714 | fault_msg: |
575ca735 VN |
715 | /* fault info: */ |
716 | .ascii "BUG: Int %d: CR2 %p\n" | |
4c5023a3 PA |
717 | /* regs pushed in early_idt_handler: */ |
718 | .ascii " EDI %p ESI %p EBP %p EBX %p\n" | |
719 | .ascii " ESP %p ES %p DS %p\n" | |
720 | .ascii " EDX %p ECX %p EAX %p\n" | |
575ca735 | 721 | /* fault frame: */ |
4c5023a3 | 722 | .ascii " vec %p err %p EIP %p CS %p flg %p\n" |
575ca735 VN |
723 | .ascii "Stack: %p %p %p %p %p %p %p %p\n" |
724 | .ascii " %p %p %p %p %p %p %p %p\n" | |
725 | .asciz " %p %p %p %p %p %p %p %p\n" | |
ec5c0926 | 726 | |
9702785a | 727 | #include "../../x86/xen/xen-head.S" |
5ead97c8 | 728 | |
1da177e4 LT |
729 | /* |
730 | * The IDT and GDT 'descriptors' are a strange 48-bit object | |
731 | * only used by the lidt and lgdt instructions. They are not | |
732 | * like usual segment descriptors - they consist of a 16-bit | |
733 | * segment size, and 32-bit linear address value: | |
734 | */ | |
735 | ||
4c5023a3 | 736 | .data |
1da177e4 LT |
737 | .globl boot_gdt_descr |
738 | .globl idt_descr | |
1da177e4 LT |
739 | |
740 | ALIGN | |
741 | # early boot GDT descriptor (must use 1:1 address mapping) | |
742 | .word 0 # 32 bit align gdt_desc.address | |
743 | boot_gdt_descr: | |
744 | .word __BOOT_DS+7 | |
52de74dd | 745 | .long boot_gdt - __PAGE_OFFSET |
1da177e4 LT |
746 | |
747 | .word 0 # 32-bit align idt_desc.address | |
748 | idt_descr: | |
749 | .word IDT_ENTRIES*8-1 # idt contains 256 entries | |
750 | .long idt_table | |
751 | ||
752 | # boot GDT descriptor (later on used by CPU#0): | |
753 | .word 0 # 32 bit align gdt_desc.address | |
2a57ff1a | 754 | ENTRY(early_gdt_descr) |
1da177e4 | 755 | .word GDT_ENTRIES*8-1 |
dd17c8f7 | 756 | .long gdt_page /* Overwritten for secondary CPUs */ |
1da177e4 | 757 | |
1da177e4 | 758 | /* |
52de74dd | 759 | * The boot_gdt must mirror the equivalent in setup.S and is |
1da177e4 LT |
760 | * used only for booting. |
761 | */ | |
762 | .align L1_CACHE_BYTES | |
52de74dd | 763 | ENTRY(boot_gdt) |
1da177e4 LT |
764 | .fill GDT_ENTRY_BOOT_CS,8,0 |
765 | .quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */ | |
766 | .quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */ |