locore.s revision 27993
1/*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * William Jolitz. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: @(#)locore.s 7.3 (Berkeley) 5/13/91 37 * $Id: locore.s,v 1.93 1997/07/20 08:37:18 bde Exp $ 38 * 39 * originally from: locore.s, by William F. Jolitz 40 * 41 * Substantially rewritten by David Greenman, Rod Grimes, 42 * Bruce Evans, Wolfgang Solfrank, Poul-Henning Kamp 43 * and many others. 44 */ 45 46#include "apm.h" 47#include "opt_cpu.h" 48#include "opt_ddb.h" 49#include "opt_userconfig.h" 50 51#include <sys/syscall.h> 52#include <sys/reboot.h> 53 54#include <machine/asmacros.h> 55#include <machine/cputypes.h> 56#include <machine/psl.h> 57#include <machine/pmap.h> 58#include <machine/specialreg.h> 59 60#include "assym.s" 61 62/* 63 * XXX 64 * 65 * Note: This version greatly munged to avoid various assembler errors 66 * that may be fixed in newer versions of gas. Perhaps newer versions 67 * will have more pleasant appearance. 68 */ 69 70/* 71 * PTmap is recursive pagemap at top of virtual address space. 72 * Within PTmap, the page directory can be found (third indirection). 73 */ 74 .globl _PTmap,_PTD,_PTDpde 75 .set _PTmap,(PTDPTDI << PDRSHIFT) 76 .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 77 .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 78 79/* 80 * APTmap, APTD is the alternate recursive pagemap. 81 * It's used when modifying another process's page tables. 82 */ 83 .globl _APTmap,_APTD,_APTDpde 84 .set _APTmap,APTDPTDI << PDRSHIFT 85 .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 86 .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 87 88#ifdef SMP 89 .globl _SMP_prvstart 90 .set _SMP_prvstart,(MPPTDI << PDRSHIFT) 91 92 .globl _SMP_prvpage,_SMP_prvpt,_lapic,_SMP_ioapic 93 .set _SMP_prvpage,_SMP_prvstart 94 .set _SMP_prvpt,_SMP_prvstart + PAGE_SIZE 95 .set _lapic,_SMP_prvstart + (2 * PAGE_SIZE) 96 .set _SMP_ioapic,_SMP_prvstart + (16 * PAGE_SIZE) 97 98 .globl _cpuid,_curproc,_curpcb,_npxproc,_runtime,_cpu_lockid 99 .globl _common_tss,_other_cpus 100 .set _cpuid,_SMP_prvpage+0 101 .set _curproc,_SMP_prvpage+4 102 .set _curpcb,_SMP_prvpage+8 103 .set _npxproc,_SMP_prvpage+12 104 .set _runtime,_SMP_prvpage+16 /* 8 bytes struct timeval */ 105 .set _cpu_lockid,_SMP_prvpage+24 106 .set _common_tss,_SMP_prvpage+28 /* 104 bytes long, next = 132 */ 107 .set _other_cpus,_SMP_prvpage+132 /* bitmap of available CPUs, 108 excluding ourself */ 109 110/* Fetch the .set's for the local apic */ 111#include "i386/i386/mp_apicdefs.s" 112 113#endif 114 115/* 116 * Globals 117 */ 118 .data 119 ALIGN_DATA /* just to be sure */ 120 121 .globl HIDENAME(tmpstk) 122 .space 0x2000 /* space for tmpstk - temporary stack */ 123HIDENAME(tmpstk): 124 125 .globl _boothowto,_bootdev 126 127 .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 128 .globl _cpu_high, _cpu_feature 129 130_cpu: .long 0 /* are we 386, 386sx, or 486 */ 131_cpu_id: .long 0 /* stepping ID */ 132_cpu_high: .long 0 /* highest arg to CPUID */ 133_cpu_feature: .long 0 /* features */ 134_cpu_vendor: .space 20 /* CPU origin code */ 135_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 136 137_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 138physfree: .long 0 /* phys addr of next free page */ 139 140#ifdef SMP 141cpu0pp: .long 0 /* phys addr cpu0 private pg */ 142cpu0pt: .long 0 /* phys addr cpu0 private pt */ 143 144 .globl _cpu0prvpage,_cpu0prvpt 145_cpu0prvpage: .long 0 /* relocated version */ 146_cpu0prvpt: .long 0 /* relocated version */ 147#endif /* SMP */ 148 149 .globl _IdlePTD 150_IdlePTD: .long 0 /* phys addr of kernel PTD */ 151 152#ifdef SMP 153 .globl _KPTphys 154#endif 155_KPTphys: .long 0 /* phys addr of kernel page tables */ 156 157 .globl _proc0paddr 158_proc0paddr: .long 0 /* address of proc 0 address space */ 159p0upa: .long 0 /* phys addr of proc0's UPAGES */ 160 161#ifdef BDE_DEBUGGER 162 .globl _bdb_exists /* flag to indicate BDE debugger is present */ 163_bdb_exists: .long 0 164#endif 165 166 167/********************************************************************** 168 * 169 * Some handy macros 170 * 171 */ 172 173#define R(foo) ((foo)-KERNBASE) 174 175#define ALLOCPAGES(foo) \ 176 movl R(physfree), %esi ; \ 177 movl $((foo)*PAGE_SIZE), %eax ; \ 178 addl %esi, %eax ; \ 179 movl %eax, R(physfree) ; \ 180 movl %esi, %edi ; \ 181 movl $((foo)*PAGE_SIZE),%ecx ; \ 182 xorl %eax,%eax ; \ 183 cld ; \ 184 rep ; \ 185 stosb 186 187/* 188 * fillkpt 189 * eax = page frame address 190 * ebx = index into page table 191 * ecx = how many pages to map 192 * base = base address of page dir/table 193 * prot = protection bits 194 */ 195#define fillkpt(base, prot) \ 196 shll $2,%ebx ; \ 197 addl base,%ebx ; \ 198 orl $PG_V,%eax ; \ 199 orl prot,%eax ; \ 2001: movl %eax,(%ebx) ; \ 201 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 202 addl $4,%ebx ; /* next pte */ \ 203 loop 1b 204 205/* 206 * fillkptphys(prot) 207 * eax = physical address 208 * ecx = how many pages to map 209 * prot = protection bits 210 */ 211#define fillkptphys(prot) \ 212 movl %eax, %ebx ; \ 213 shrl $PAGE_SHIFT, %ebx ; \ 214 fillkpt(R(_KPTphys), prot) 215 216 .text 217/********************************************************************** 218 * 219 * This is where the bootblocks start us, set the ball rolling... 220 * 221 */ 222NON_GPROF_ENTRY(btext) 223 224#ifdef PC98 225 jmp 1f 226 .globl _pc98_system_parameter 227 .org 0x400 228_pc98_system_parameter: 229 .space 0x240 /* BIOS parameter block */ 2301: 231 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 232 movl $0xa1000,%esi 233 movl $0x100000,%edi 234 movl $0x0630,%ecx 235 cld 236 rep 237 movsb 238#else /* IBM-PC */ 239#ifdef BDE_DEBUGGER 240#ifdef BIOS_STEALS_3K 241 cmpl $0x0375c339,0x95504 242#else 243 cmpl $0x0375c339,0x96104 /* XXX - debugger signature */ 244#endif 245 jne 1f 246 movb $1,R(_bdb_exists) 2471: 248#endif 249 250/* Tell the bios to warmboot next time */ 251 movw $0x1234,0x472 252#endif /* PC98 */ 253 254/* Set up a real frame in case the double return in newboot is executed. */ 255 pushl %ebp 256 movl %esp, %ebp 257 258/* Don't trust what the BIOS gives for eflags. */ 259 pushl $PSL_KERNEL 260 popfl 261 262/* 263 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 264 * to set %cs, %ds, %es and %ss. 265 */ 266 mov %ds, %ax 267 mov %ax, %fs 268 mov %ax, %gs 269 270 call recover_bootinfo 271 272/* Get onto a stack that we can trust. */ 273/* 274 * XXX this step is delayed in case recover_bootinfo needs to return via 275 * the old stack, but it need not be, since recover_bootinfo actually 276 * returns via the old frame. 277 */ 278 movl $R(HIDENAME(tmpstk)),%esp 279 280#ifdef PC98 281 testb $0x02,0x100620 /* pc98_machine_type & M_EPSON_PC98 */ 282 jz 3f 283 cmpb $0x0b,0x100624 /* epson_machine_id <= 0x0b */ 284 ja 3f 285 286 /* count up memory */ 287 movl $0x100000,%eax /* next, talley remaining memory */ 288 movl $0xFFF-0x100,%ecx 2891: movl 0(%eax),%ebx /* save location to check */ 290 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 291 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 292 jne 2f 293 movl %ebx,0(%eax) /* restore memory */ 294 addl $PAGE_SIZE,%eax 295 loop 1b 2962: subl $0x100000,%eax 297 shrl $17,%eax 298 movb %al,0x100401 2993: 300#endif 301 302 call identify_cpu 303 304/* clear bss */ 305/* 306 * XXX this should be done a little earlier. 307 * 308 * XXX we don't check that there is memory for our bss and page tables 309 * before using it. 310 * 311 * XXX the boot program somewhat bogusly clears the bss. We still have 312 * to do it in case we were unzipped by kzipboot. Then the boot program 313 * only clears kzipboot's bss. 314 * 315 * XXX the gdt and idt are still somewhere in the boot program. We 316 * depend on the convention that the boot program is below 1MB and we 317 * are above 1MB to keep the gdt and idt away from the bss and page 318 * tables. The idt is only used if BDE_DEBUGGER is enabled. 319 */ 320 movl $R(_end),%ecx 321 movl $R(_edata),%edi 322 subl %edi,%ecx 323 xorl %eax,%eax 324 cld 325 rep 326 stosb 327 328#if NAPM > 0 329/* 330 * XXX it's not clear that APM can live in the current environonment. 331 * Only pc-relative addressing works. 332 */ 333 call _apm_setup 334#endif 335 336 call create_pagetables 337 338#ifdef VM86 339/* 340 * If the CPU has support for VME, turn it on. 341 */ 342 testl $CPUID_VME, R(_cpu_feature) 343 jz 1f 344 movl %cr4, %eax 345 orl $CR4_VME, %eax 346 movl %eax, %cr4 3471: 348#endif /* VM86 */ 349 350#ifdef BDE_DEBUGGER 351/* 352 * Adjust as much as possible for paging before enabling paging so that the 353 * adjustments can be traced. 354 */ 355 call bdb_prepare_paging 356#endif 357 358/* Now enable paging */ 359 movl R(_IdlePTD), %eax 360 movl %eax,%cr3 /* load ptd addr into mmu */ 361 movl %cr0,%eax /* get control word */ 362 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 363 movl %eax,%cr0 /* and let's page NOW! */ 364 365#ifdef BDE_DEBUGGER 366/* 367 * Complete the adjustments for paging so that we can keep tracing through 368 * initi386() after the low (physical) addresses for the gdt and idt become 369 * invalid. 370 */ 371 call bdb_commit_paging 372#endif 373 374 pushl $begin /* jump to high virtualized address */ 375 ret 376 377/* now running relocated at KERNBASE where the system is linked to run */ 378begin: 379 /* set up bootstrap stack */ 380 movl _proc0paddr,%esp /* location of in-kernel pages */ 381 addl $UPAGES*PAGE_SIZE,%esp /* bootstrap stack end location */ 382 xorl %eax,%eax /* mark end of frames */ 383 movl %eax,%ebp 384 movl _proc0paddr,%eax 385 movl _IdlePTD, %esi 386 movl %esi,PCB_CR3(%eax) 387 388 movl physfree, %esi 389 pushl %esi /* value of first for init386(first) */ 390 call _init386 /* wire 386 chip for unix operation */ 391 popl %esi 392 393 .globl __ucodesel,__udatasel 394 395 pushl $0 /* unused */ 396 pushl __udatasel /* ss */ 397 pushl $0 /* esp - filled in by execve() */ 398 pushl $PSL_USER /* eflags (IOPL 0, int enab) */ 399 pushl __ucodesel /* cs */ 400 pushl $0 /* eip - filled in by execve() */ 401 subl $(12*4),%esp /* space for rest of registers */ 402 403 pushl %esp /* call main with frame pointer */ 404 call _main /* autoconfiguration, mountroot etc */ 405 406 hlt /* never returns to here */ 407 408/* 409 * When starting init, call this to configure the process for user 410 * mode. This will be inherited by other processes. 411 */ 412NON_GPROF_ENTRY(prepare_usermode) 413 /* 414 * Now we've run main() and determined what cpu-type we are, we can 415 * enable write protection and alignment checking on i486 cpus and 416 * above. 417 */ 418#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) 419 cmpl $CPUCLASS_386,_cpu_class 420 je 1f 421 movl %cr0,%eax /* get control word */ 422 orl $CR0_WP|CR0_AM,%eax /* enable i486 features */ 423 movl %eax,%cr0 /* and do it */ 4241: 425#endif 426 /* 427 * on return from main(), we are process 1 428 * set up address space and stack so that we can 'return' to user mode 429 */ 430 movl __ucodesel,%eax 431 movl __udatasel,%ecx 432 433#if 0 434 movl %cx,%ds 435#endif 436 movl %cx,%es 437 movl %ax,%fs /* double map cs to fs */ 438 movl %cx,%gs /* and ds to gs */ 439 ret /* goto user! */ 440 441 442#define LCALL(x,y) .byte 0x9a ; .long y ; .word x 443 444/* 445 * Signal trampoline, copied to top of user stack 446 */ 447NON_GPROF_ENTRY(sigcode) 448 call SIGF_HANDLER(%esp) 449 lea SIGF_SC(%esp),%eax /* scp (the call may have clobbered the */ 450 /* copy at 8(%esp)) */ 451 pushl %eax 452 pushl %eax /* junk to fake return address */ 453 movl $SYS_sigreturn,%eax /* sigreturn() */ 454 LCALL(0x7,0) /* enter kernel with args on stack */ 455 hlt /* never gets here */ 456 ALIGN_TEXT 457_esigcode: 458 459 .data 460 .globl _szsigcode 461_szsigcode: 462 .long _esigcode-_sigcode 463 .text 464 465/********************************************************************** 466 * 467 * Recover the bootinfo passed to us from the boot program 468 * 469 */ 470recover_bootinfo: 471 /* 472 * This code is called in different ways depending on what loaded 473 * and started the kernel. This is used to detect how we get the 474 * arguments from the other code and what we do with them. 475 * 476 * Old disk boot blocks: 477 * (*btext)(howto, bootdev, cyloffset, esym); 478 * [return address == 0, and can NOT be returned to] 479 * [cyloffset was not supported by the FreeBSD boot code 480 * and always passed in as 0] 481 * [esym is also known as total in the boot code, and 482 * was never properly supported by the FreeBSD boot code] 483 * 484 * Old diskless netboot code: 485 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 486 * [return address != 0, and can NOT be returned to] 487 * If we are being booted by this code it will NOT work, 488 * so we are just going to halt if we find this case. 489 * 490 * New uniform boot code: 491 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 492 * [return address != 0, and can be returned to] 493 * 494 * There may seem to be a lot of wasted arguments in here, but 495 * that is so the newer boot code can still load very old kernels 496 * and old boot code can load new kernels. 497 */ 498 499 /* 500 * The old style disk boot blocks fake a frame on the stack and 501 * did an lret to get here. The frame on the stack has a return 502 * address of 0. 503 */ 504 cmpl $0,4(%ebp) 505 je olddiskboot 506 507 /* 508 * We have some form of return address, so this is either the 509 * old diskless netboot code, or the new uniform code. That can 510 * be detected by looking at the 5th argument, if it is 0 511 * we are being booted by the new uniform boot code. 512 */ 513 cmpl $0,24(%ebp) 514 je newboot 515 516 /* 517 * Seems we have been loaded by the old diskless boot code, we 518 * don't stand a chance of running as the diskless structure 519 * changed considerably between the two, so just halt. 520 */ 521 hlt 522 523 /* 524 * We have been loaded by the new uniform boot code. 525 * Let's check the bootinfo version, and if we do not understand 526 * it we return to the loader with a status of 1 to indicate this error 527 */ 528newboot: 529 movl 28(%ebp),%ebx /* &bootinfo.version */ 530 movl BI_VERSION(%ebx),%eax 531 cmpl $1,%eax /* We only understand version 1 */ 532 je 1f 533 movl $1,%eax /* Return status */ 534 leave 535 /* 536 * XXX this returns to our caller's caller (as is required) since 537 * we didn't set up a frame and our caller did. 538 */ 539 ret 540 5411: 542 /* 543 * If we have a kernelname copy it in 544 */ 545 movl BI_KERNELNAME(%ebx),%esi 546 cmpl $0,%esi 547 je 2f /* No kernelname */ 548 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 549 movl $R(_kernelname),%edi 550 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 551 je 1f 552 movb $'/',(%edi) 553 incl %edi 554 decl %ecx 5551: 556 cld 557 rep 558 movsb 559 5602: 561 /* 562 * Determine the size of the boot loader's copy of the bootinfo 563 * struct. This is impossible to do properly because old versions 564 * of the struct don't contain a size field and there are 2 old 565 * versions with the same version number. 566 */ 567 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 568 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 569 je got_bi_size /* no, sizeless version */ 570 movl BI_SIZE(%ebx),%ecx 571got_bi_size: 572 573 /* 574 * Copy the common part of the bootinfo struct 575 */ 576 movl %ebx,%esi 577 movl $R(_bootinfo),%edi 578 cmpl $BOOTINFO_SIZE,%ecx 579 jbe got_common_bi_size 580 movl $BOOTINFO_SIZE,%ecx 581got_common_bi_size: 582 cld 583 rep 584 movsb 585 586#ifdef NFS 587#ifndef BOOTP_NFSV3 588 /* 589 * If we have a nfs_diskless structure copy it in 590 */ 591 movl BI_NFS_DISKLESS(%ebx),%esi 592 cmpl $0,%esi 593 je olddiskboot 594 movl $R(_nfs_diskless),%edi 595 movl $NFSDISKLESS_SIZE,%ecx 596 cld 597 rep 598 movsb 599 movl $R(_nfs_diskless_valid),%edi 600 movl $1,(%edi) 601#endif 602#endif 603 604 /* 605 * The old style disk boot. 606 * (*btext)(howto, bootdev, cyloffset, esym); 607 * Note that the newer boot code just falls into here to pick 608 * up howto and bootdev, cyloffset and esym are no longer used 609 */ 610olddiskboot: 611 movl 8(%ebp),%eax 612 movl %eax,R(_boothowto) 613 movl 12(%ebp),%eax 614 movl %eax,R(_bootdev) 615 616#if defined(USERCONFIG_BOOT) && defined(USERCONFIG) 617#ifdef PC98 618 movl $0x90200, %esi 619#else 620 movl $0x10200, %esi 621#endif 622 movl $R(_userconfig_from_boot),%edi 623 movl $512,%ecx 624 cld 625 rep 626 movsb 627#endif /* USERCONFIG_BOOT */ 628 629 ret 630 631 632/********************************************************************** 633 * 634 * Identify the CPU and initialize anything special about it 635 * 636 */ 637identify_cpu: 638 639 /* Try to toggle alignment check flag; does not exist on 386. */ 640 pushfl 641 popl %eax 642 movl %eax,%ecx 643 orl $PSL_AC,%eax 644 pushl %eax 645 popfl 646 pushfl 647 popl %eax 648 xorl %ecx,%eax 649 andl $PSL_AC,%eax 650 pushl %ecx 651 popfl 652 653 testl %eax,%eax 654 jnz try486 655 656 /* NexGen CPU does not have aligment check flag. */ 657 pushfl 658 movl $0x5555, %eax 659 xorl %edx, %edx 660 movl $2, %ecx 661 clc 662 divl %ecx 663 jz trynexgen 664 popfl 665 movl $CPU_386,R(_cpu) 666 jmp 3f 667 668trynexgen: 669 popfl 670 movl $CPU_NX586,R(_cpu) 671 movl $0x4778654e,R(_cpu_vendor) # store vendor string 672 movl $0x72446e65,R(_cpu_vendor+4) 673 movl $0x6e657669,R(_cpu_vendor+8) 674 movl $0,R(_cpu_vendor+12) 675 jmp 3f 676 677try486: /* Try to toggle identification flag; does not exist on early 486s. */ 678 pushfl 679 popl %eax 680 movl %eax,%ecx 681 xorl $PSL_ID,%eax 682 pushl %eax 683 popfl 684 pushfl 685 popl %eax 686 xorl %ecx,%eax 687 andl $PSL_ID,%eax 688 pushl %ecx 689 popfl 690 691 testl %eax,%eax 692 jnz trycpuid 693 movl $CPU_486,R(_cpu) 694 695 /* 696 * Check Cyrix CPU 697 * Cyrix CPUs do not change the undefined flags following 698 * execution of the divide instruction which divides 5 by 2. 699 * 700 * Note: CPUID is enabled on M2, so it passes another way. 701 */ 702 pushfl 703 movl $0x5555, %eax 704 xorl %edx, %edx 705 movl $2, %ecx 706 clc 707 divl %ecx 708 jnc trycyrix 709 popfl 710 jmp 3f /* You may use Intel CPU. */ 711 712trycyrix: 713 popfl 714 /* 715 * IBM Bluelighting CPU also doesn't change the undefined flags. 716 * Because IBM doesn't disclose the information for Bluelighting 717 * CPU, we couldn't distinguish it from Cyrix's (including IBM 718 * brand of Cyrix CPUs). 719 */ 720 movl $0x69727943,R(_cpu_vendor) # store vendor string 721 movl $0x736e4978,R(_cpu_vendor+4) 722 movl $0x64616574,R(_cpu_vendor+8) 723 jmp 3f 724 725trycpuid: /* Use the `cpuid' instruction. */ 726 xorl %eax,%eax 727 .byte 0x0f,0xa2 # cpuid 0 728 movl %eax,R(_cpu_high) # highest capability 729 movl %ebx,R(_cpu_vendor) # store vendor string 730 movl %edx,R(_cpu_vendor+4) 731 movl %ecx,R(_cpu_vendor+8) 732 movb $0,R(_cpu_vendor+12) 733 734 movl $1,%eax 735 .byte 0x0f,0xa2 # cpuid 1 736 movl %eax,R(_cpu_id) # store cpu_id 737 movl %edx,R(_cpu_feature) # store cpu_feature 738 rorl $8,%eax # extract family type 739 andl $15,%eax 740 cmpl $5,%eax 741 jae 1f 742 743 /* less than Pentium; must be 486 */ 744 movl $CPU_486,R(_cpu) 745 jmp 3f 7461: 747 /* a Pentium? */ 748 cmpl $5,%eax 749 jne 2f 750 movl $CPU_586,R(_cpu) 751 jmp 3f 7522: 753 /* Greater than Pentium...call it a Pentium Pro */ 754 movl $CPU_686,R(_cpu) 7553: 756 ret 757 758 759/********************************************************************** 760 * 761 * Create the first page directory and its page tables. 762 * 763 */ 764 765create_pagetables: 766 767 testl $CPUID_PGE, R(_cpu_feature) 768 jz 1f 769 movl %cr4, %eax 770 orl $CR4_PGE, %eax 771 movl %eax, %cr4 7721: 773 774/* Find end of kernel image (rounded up to a page boundary). */ 775 movl $R(_end),%esi 776 777/* include symbols in "kernel image" if they are loaded and useful */ 778#ifdef DDB 779 movl R(_bootinfo+BI_ESYMTAB),%edi 780 testl %edi,%edi 781 je over_symalloc 782 movl %edi,%esi 783 movl $KERNBASE,%edi 784 addl %edi,R(_bootinfo+BI_SYMTAB) 785 addl %edi,R(_bootinfo+BI_ESYMTAB) 786over_symalloc: 787#endif 788 789 addl $PAGE_MASK,%esi 790 andl $~PAGE_MASK,%esi 791 movl %esi,R(_KERNend) /* save end of kernel */ 792 movl %esi,R(physfree) /* next free page is at end of kernel */ 793 794/* Allocate Kernel Page Tables */ 795 ALLOCPAGES(NKPT) 796 movl %esi,R(_KPTphys) 797 798/* Allocate Page Table Directory */ 799 ALLOCPAGES(1) 800 movl %esi,R(_IdlePTD) 801 802/* Allocate UPAGES */ 803 ALLOCPAGES(UPAGES) 804 movl %esi,R(p0upa) 805 addl $KERNBASE, %esi 806 movl %esi, R(_proc0paddr) 807 808#ifdef SMP 809/* Allocate cpu0's private data page */ 810 ALLOCPAGES(1) 811 movl %esi,R(cpu0pp) 812 addl $KERNBASE, %esi 813 movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 814 815/* Allocate cpu0's private page table for mapping priv page, apic, etc */ 816 ALLOCPAGES(1) 817 movl %esi,R(cpu0pt) 818 addl $KERNBASE, %esi 819 movl %esi, R(_cpu0prvpt) /* relocated to KVM space */ 820#endif /* SMP */ 821 822/* Map read-only from zero to the end of the kernel text section */ 823 xorl %eax, %eax 824#ifdef BDE_DEBUGGER 825/* If the debugger is present, actually map everything read-write. */ 826 cmpl $0,R(_bdb_exists) 827 jne map_read_write 828#endif 829 xorl %edx,%edx 830 831#if !defined(SMP) 832 testl $CPUID_PGE, R(_cpu_feature) 833 jz 2f 834 orl $PG_G,%edx 835#endif 836 8372: movl $R(_etext),%ecx 838 addl $PAGE_MASK,%ecx 839 shrl $PAGE_SHIFT,%ecx 840 fillkptphys(%edx) 841 842/* Map read-write, data, bss and symbols */ 843 movl $R(_etext),%eax 844 addl $PAGE_MASK, %eax 845 andl $~PAGE_MASK, %eax 846map_read_write: 847 movl $PG_RW,%edx 848#if !defined(SMP) 849 testl $CPUID_PGE, R(_cpu_feature) 850 jz 1f 851 orl $PG_G,%edx 852#endif 853 8541: movl R(_KERNend),%ecx 855 subl %eax,%ecx 856 shrl $PAGE_SHIFT,%ecx 857 fillkptphys(%edx) 858 859/* Map page directory. */ 860 movl R(_IdlePTD), %eax 861 movl $1, %ecx 862 fillkptphys($PG_RW) 863 864/* Map proc0's UPAGES in the physical way ... */ 865 movl R(p0upa), %eax 866 movl $UPAGES, %ecx 867 fillkptphys($PG_RW) 868 869/* Map ISA hole */ 870 movl $ISA_HOLE_START, %eax 871 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 872 fillkptphys($PG_RW) 873 874#ifdef SMP 875/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 876 movl R(cpu0pp), %eax 877 movl $1, %ecx 878 fillkptphys($PG_RW) 879 880/* Map cpu0's private page table into global kmem FWIW */ 881 movl R(cpu0pt), %eax 882 movl $1, %ecx 883 fillkptphys($PG_RW) 884 885/* Map the private page into the private page table into private space */ 886 movl R(cpu0pp), %eax 887 movl $0, %ebx /* pte offset = 0 */ 888 movl $1, %ecx /* one private page coming right up */ 889 fillkpt(R(cpu0pt), $PG_RW) 890 891/* Map the page table page into private space */ 892 movl R(cpu0pt), %eax 893 movl $1, %ebx /* pte offset = 1 */ 894 movl $1, %ecx /* one private pt coming right up */ 895 fillkpt(R(cpu0pt), $PG_RW) 896 897/* ... and put the page table table in the pde. */ 898 movl R(cpu0pt), %eax 899 movl $MPPTDI, %ebx 900 movl $1, %ecx 901 fillkpt(R(_IdlePTD), $PG_RW) 902#endif /* SMP */ 903 904/* install a pde for temporary double map of bottom of VA */ 905 movl R(_KPTphys), %eax 906 xorl %ebx, %ebx 907 movl $1, %ecx 908 fillkpt(R(_IdlePTD), $PG_RW) 909 910/* install pde's for pt's */ 911 movl R(_KPTphys), %eax 912 movl $KPTDI, %ebx 913 movl $NKPT, %ecx 914 fillkpt(R(_IdlePTD), $PG_RW) 915 916/* install a pde recursively mapping page directory as a page table */ 917 movl R(_IdlePTD), %eax 918 movl $PTDPTDI, %ebx 919 movl $1,%ecx 920 fillkpt(R(_IdlePTD), $PG_RW) 921 922 ret 923 924#ifdef BDE_DEBUGGER 925bdb_prepare_paging: 926 cmpl $0,R(_bdb_exists) 927 je bdb_prepare_paging_exit 928 929 subl $6,%esp 930 931 /* 932 * Copy and convert debugger entries from the bootstrap gdt and idt 933 * to the kernel gdt and idt. Everything is still in low memory. 934 * Tracing continues to work after paging is enabled because the 935 * low memory addresses remain valid until everything is relocated. 936 * However, tracing through the setidt() that initializes the trace 937 * trap will crash. 938 */ 939 sgdt (%esp) 940 movl 2(%esp),%esi /* base address of bootstrap gdt */ 941 movl $R(_gdt),%edi 942 movl %edi,2(%esp) /* prepare to load kernel gdt */ 943 movl $8*18/4,%ecx 944 cld 945 rep /* copy gdt */ 946 movsl 947 movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 948 movb $0x92,-8+5(%edi) 949 lgdt (%esp) 950 951 sidt (%esp) 952 movl 2(%esp),%esi /* base address of current idt */ 953 movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 954 movw 8(%esi),%ax 955 movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 956 movl 8+2(%esi),%eax 957 movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 958 movl 24+4(%esi),%eax /* same for bpt descriptor */ 959 movw 24(%esi),%ax 960 movl %eax,R(bdb_bpt_ljmp+1) 961 movl 24+2(%esi),%eax 962 movw %ax,R(bdb_bpt_ljmp+5) 963 movl $R(_idt),%edi 964 movl %edi,2(%esp) /* prepare to load kernel idt */ 965 movl $8*4/4,%ecx 966 cld 967 rep /* copy idt */ 968 movsl 969 lidt (%esp) 970 971 addl $6,%esp 972 973bdb_prepare_paging_exit: 974 ret 975 976/* Relocate debugger gdt entries and gdt and idt pointers. */ 977bdb_commit_paging: 978 cmpl $0,_bdb_exists 979 je bdb_commit_paging_exit 980 981 movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 982 movl $9,%ecx 983reloc_gdt: 984 movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 985 addl $8,%eax /* now KERNBASE>>24 */ 986 loop reloc_gdt 987 988 subl $6,%esp 989 sgdt (%esp) 990 addl $KERNBASE,2(%esp) 991 lgdt (%esp) 992 sidt (%esp) 993 addl $KERNBASE,2(%esp) 994 lidt (%esp) 995 addl $6,%esp 996 997 int $3 998 999bdb_commit_paging_exit: 1000 ret 1001 1002#endif /* BDE_DEBUGGER */ 1003