locore.s revision 36596
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 1.107 1998/04/06 15:42:26 peter 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_bootp.h" 48#include "opt_cpu.h" 49#include "opt_ddb.h" 50#include "opt_nfs.h" 51#include "opt_userconfig.h" 52#include "opt_vm86.h" 53 54#include <sys/syscall.h> 55#include <sys/reboot.h> 56 57#include <machine/asmacros.h> 58#include <machine/cputypes.h> 59#include <machine/psl.h> 60#include <machine/pmap.h> 61#include <machine/specialreg.h> 62 63#include "assym.s" 64 65/* 66 * XXX 67 * 68 * Note: This version greatly munged to avoid various assembler errors 69 * that may be fixed in newer versions of gas. Perhaps newer versions 70 * will have more pleasant appearance. 71 */ 72 73/* 74 * PTmap is recursive pagemap at top of virtual address space. 75 * Within PTmap, the page directory can be found (third indirection). 76 */ 77 .globl _PTmap,_PTD,_PTDpde 78 .set _PTmap,(PTDPTDI << PDRSHIFT) 79 .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 80 .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 81 82/* 83 * APTmap, APTD is the alternate recursive pagemap. 84 * It's used when modifying another process's page tables. 85 */ 86 .globl _APTmap,_APTD,_APTDpde 87 .set _APTmap,APTDPTDI << PDRSHIFT 88 .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 89 .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 90 91/* 92 * Globals 93 */ 94 .data 95 ALIGN_DATA /* just to be sure */ 96 97 .globl HIDENAME(tmpstk) 98 .space 0x2000 /* space for tmpstk - temporary stack */ 99HIDENAME(tmpstk): 100 101 .globl _boothowto,_bootdev 102 103 .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 104 .globl _cpu_high, _cpu_feature 105 106_cpu: .long 0 /* are we 386, 386sx, or 486 */ 107_cpu_id: .long 0 /* stepping ID */ 108_cpu_high: .long 0 /* highest arg to CPUID */ 109_cpu_feature: .long 0 /* features */ 110_cpu_vendor: .space 20 /* CPU origin code */ 111_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 112 113_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 114physfree: .long 0 /* phys addr of next free page */ 115 116#ifdef SMP 117cpu0pp: .long 0 /* phys addr cpu0 private pg */ 118cpu0pt: .long 0 /* phys addr cpu0 private pt */ 119 120 .globl _cpu0prvpage,_cpu0prvpt 121_cpu0prvpage: .long 0 /* relocated version */ 122_cpu0prvpt: .long 0 /* relocated version */ 123#endif /* SMP */ 124 125 .globl _IdlePTD 126_IdlePTD: .long 0 /* phys addr of kernel PTD */ 127 128#ifdef SMP 129 .globl _KPTphys 130#endif 131_KPTphys: .long 0 /* phys addr of kernel page tables */ 132 133 .globl _proc0paddr 134_proc0paddr: .long 0 /* address of proc 0 address space */ 135p0upa: .long 0 /* phys addr of proc0's UPAGES */ 136 137#ifdef VM86 138 .globl _vm86paddr, _vm86pa 139_vm86paddr: .long 0 /* address of vm86 region */ 140_vm86pa: .long 0 /* phys addr of vm86 region */ 141#endif 142 143#ifdef BDE_DEBUGGER 144 .globl _bdb_exists /* flag to indicate BDE debugger is present */ 145_bdb_exists: .long 0 146#endif 147 148 149/********************************************************************** 150 * 151 * Some handy macros 152 * 153 */ 154 155#define R(foo) ((foo)-KERNBASE) 156 157#define ALLOCPAGES(foo) \ 158 movl R(physfree), %esi ; \ 159 movl $((foo)*PAGE_SIZE), %eax ; \ 160 addl %esi, %eax ; \ 161 movl %eax, R(physfree) ; \ 162 movl %esi, %edi ; \ 163 movl $((foo)*PAGE_SIZE),%ecx ; \ 164 xorl %eax,%eax ; \ 165 cld ; \ 166 rep ; \ 167 stosb 168 169/* 170 * fillkpt 171 * eax = page frame address 172 * ebx = index into page table 173 * ecx = how many pages to map 174 * base = base address of page dir/table 175 * prot = protection bits 176 */ 177#define fillkpt(base, prot) \ 178 shll $2,%ebx ; \ 179 addl base,%ebx ; \ 180 orl $PG_V,%eax ; \ 181 orl prot,%eax ; \ 1821: movl %eax,(%ebx) ; \ 183 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 184 addl $4,%ebx ; /* next pte */ \ 185 loop 1b 186 187/* 188 * fillkptphys(prot) 189 * eax = physical address 190 * ecx = how many pages to map 191 * prot = protection bits 192 */ 193#define fillkptphys(prot) \ 194 movl %eax, %ebx ; \ 195 shrl $PAGE_SHIFT, %ebx ; \ 196 fillkpt(R(_KPTphys), prot) 197 198 .text 199/********************************************************************** 200 * 201 * This is where the bootblocks start us, set the ball rolling... 202 * 203 */ 204NON_GPROF_ENTRY(btext) 205 206#ifdef PC98 207 jmp 1f 208 .globl _pc98_system_parameter 209 .org 0x400 210_pc98_system_parameter: 211 .space 0x240 /* BIOS parameter block */ 2121: 213 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 214 movl $0xa1000,%esi 215 movl $0x100000,%edi 216 movl $0x0630,%ecx 217 cld 218 rep 219 movsb 220#else /* IBM-PC */ 221#ifdef BDE_DEBUGGER 222#ifdef BIOS_STEALS_3K 223 cmpl $0x0375c339,0x95504 224#else 225 cmpl $0x0375c339,0x96104 /* XXX - debugger signature */ 226#endif 227 jne 1f 228 movb $1,R(_bdb_exists) 2291: 230#endif 231 232/* Tell the bios to warmboot next time */ 233 movw $0x1234,0x472 234#endif /* PC98 */ 235 236/* Set up a real frame in case the double return in newboot is executed. */ 237 pushl %ebp 238 movl %esp, %ebp 239 240/* Don't trust what the BIOS gives for eflags. */ 241 pushl $PSL_KERNEL 242 popfl 243 244/* 245 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 246 * to set %cs, %ds, %es and %ss. 247 */ 248 mov %ds, %ax 249 mov %ax, %fs 250 mov %ax, %gs 251 252 call recover_bootinfo 253 254/* Get onto a stack that we can trust. */ 255/* 256 * XXX this step is delayed in case recover_bootinfo needs to return via 257 * the old stack, but it need not be, since recover_bootinfo actually 258 * returns via the old frame. 259 */ 260 movl $R(HIDENAME(tmpstk)),%esp 261 262#ifdef PC98 263 testb $0x02,0x100620 /* pc98_machine_type & M_EPSON_PC98 */ 264 jz 3f 265 cmpb $0x0b,0x100624 /* epson_machine_id <= 0x0b */ 266 ja 3f 267 268 /* count up memory */ 269 movl $0x100000,%eax /* next, talley remaining memory */ 270 movl $0xFFF-0x100,%ecx 2711: movl 0(%eax),%ebx /* save location to check */ 272 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 273 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 274 jne 2f 275 movl %ebx,0(%eax) /* restore memory */ 276 addl $PAGE_SIZE,%eax 277 loop 1b 2782: subl $0x100000,%eax 279 shrl $17,%eax 280 movb %al,0x100401 2813: 282#endif 283 284 call identify_cpu 285 286/* clear bss */ 287/* 288 * XXX this should be done a little earlier. 289 * 290 * XXX we don't check that there is memory for our bss and page tables 291 * before using it. 292 * 293 * XXX the boot program somewhat bogusly clears the bss. We still have 294 * to do it in case we were unzipped by kzipboot. Then the boot program 295 * only clears kzipboot's bss. 296 * 297 * XXX the gdt and idt are still somewhere in the boot program. We 298 * depend on the convention that the boot program is below 1MB and we 299 * are above 1MB to keep the gdt and idt away from the bss and page 300 * tables. The idt is only used if BDE_DEBUGGER is enabled. 301 */ 302 movl $R(_end),%ecx 303 movl $R(_edata),%edi 304 subl %edi,%ecx 305 xorl %eax,%eax 306 cld 307 rep 308 stosb 309 310#if NAPM > 0 311#ifndef VM86 312/* 313 * XXX it's not clear that APM can live in the current environonment. 314 * Only pc-relative addressing works. 315 */ 316 call _apm_setup 317#endif 318#endif 319 320 call create_pagetables 321 322#ifdef VM86 323/* 324 * If the CPU has support for VME, turn it on. 325 */ 326 testl $CPUID_VME, R(_cpu_feature) 327 jz 1f 328 movl %cr4, %eax 329 orl $CR4_VME, %eax 330 movl %eax, %cr4 3311: 332#endif /* VM86 */ 333 334#ifdef BDE_DEBUGGER 335/* 336 * Adjust as much as possible for paging before enabling paging so that the 337 * adjustments can be traced. 338 */ 339 call bdb_prepare_paging 340#endif 341 342/* Now enable paging */ 343 movl R(_IdlePTD), %eax 344 movl %eax,%cr3 /* load ptd addr into mmu */ 345 movl %cr0,%eax /* get control word */ 346 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 347 movl %eax,%cr0 /* and let's page NOW! */ 348 349#ifdef BDE_DEBUGGER 350/* 351 * Complete the adjustments for paging so that we can keep tracing through 352 * initi386() after the low (physical) addresses for the gdt and idt become 353 * invalid. 354 */ 355 call bdb_commit_paging 356#endif 357 358 pushl $begin /* jump to high virtualized address */ 359 ret 360 361/* now running relocated at KERNBASE where the system is linked to run */ 362begin: 363 /* set up bootstrap stack */ 364 movl _proc0paddr,%esp /* location of in-kernel pages */ 365 addl $UPAGES*PAGE_SIZE,%esp /* bootstrap stack end location */ 366 xorl %eax,%eax /* mark end of frames */ 367 movl %eax,%ebp 368 movl _proc0paddr,%eax 369 movl _IdlePTD, %esi 370 movl %esi,PCB_CR3(%eax) 371 movl $_proc0,_curproc 372 373 movl physfree, %esi 374 pushl %esi /* value of first for init386(first) */ 375 call _init386 /* wire 386 chip for unix operation */ 376 popl %esi 377 378 .globl __ucodesel,__udatasel 379 380 pushl $0 /* unused */ 381 pushl __udatasel /* ss */ 382 pushl $0 /* esp - filled in by execve() */ 383 pushl $PSL_USER /* eflags (IOPL 0, int enab) */ 384 pushl __ucodesel /* cs */ 385 pushl $0 /* eip - filled in by execve() */ 386 subl $(12*4),%esp /* space for rest of registers */ 387 388 pushl %esp /* call main with frame pointer */ 389 call _main /* autoconfiguration, mountroot etc */ 390 391 hlt /* never returns to here */ 392 393/* 394 * When starting init, call this to configure the process for user 395 * mode. This will be inherited by other processes. 396 */ 397NON_GPROF_ENTRY(prepare_usermode) 398 /* 399 * Now we've run main() and determined what cpu-type we are, we can 400 * enable write protection and alignment checking on i486 cpus and 401 * above. 402 */ 403#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) 404 cmpl $CPUCLASS_386,_cpu_class 405 je 1f 406 movl %cr0,%eax /* get control word */ 407 orl $CR0_WP|CR0_AM,%eax /* enable i486 features */ 408 movl %eax,%cr0 /* and do it */ 4091: 410#endif 411 /* 412 * on return from main(), we are process 1 413 * set up address space and stack so that we can 'return' to user mode 414 */ 415 movl __ucodesel,%eax 416 movl __udatasel,%ecx 417 418#if 0 419 movl %cx,%ds 420#endif 421 movl %cx,%es 422 movl %ax,%fs /* double map cs to fs */ 423 movl %cx,%gs /* and ds to gs */ 424 ret /* goto user! */ 425 426 427#define LCALL(x,y) .byte 0x9a ; .long y ; .word x 428 429/* 430 * Signal trampoline, copied to top of user stack 431 */ 432NON_GPROF_ENTRY(sigcode) 433 call SIGF_HANDLER(%esp) 434 lea SIGF_SC(%esp),%eax /* scp (the call may have clobbered the */ 435 /* copy at 8(%esp)) */ 436 pushl %eax 437 pushl %eax /* junk to fake return address */ 438 movl $SYS_sigreturn,%eax /* sigreturn() */ 439 LCALL(0x7,0) /* enter kernel with args on stack */ 440 hlt /* never gets here */ 441 ALIGN_TEXT 442_esigcode: 443 444 .data 445 .globl _szsigcode 446_szsigcode: 447 .long _esigcode-_sigcode 448 .text 449 450/********************************************************************** 451 * 452 * Recover the bootinfo passed to us from the boot program 453 * 454 */ 455recover_bootinfo: 456 /* 457 * This code is called in different ways depending on what loaded 458 * and started the kernel. This is used to detect how we get the 459 * arguments from the other code and what we do with them. 460 * 461 * Old disk boot blocks: 462 * (*btext)(howto, bootdev, cyloffset, esym); 463 * [return address == 0, and can NOT be returned to] 464 * [cyloffset was not supported by the FreeBSD boot code 465 * and always passed in as 0] 466 * [esym is also known as total in the boot code, and 467 * was never properly supported by the FreeBSD boot code] 468 * 469 * Old diskless netboot code: 470 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 471 * [return address != 0, and can NOT be returned to] 472 * If we are being booted by this code it will NOT work, 473 * so we are just going to halt if we find this case. 474 * 475 * New uniform boot code: 476 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 477 * [return address != 0, and can be returned to] 478 * 479 * There may seem to be a lot of wasted arguments in here, but 480 * that is so the newer boot code can still load very old kernels 481 * and old boot code can load new kernels. 482 */ 483 484 /* 485 * The old style disk boot blocks fake a frame on the stack and 486 * did an lret to get here. The frame on the stack has a return 487 * address of 0. 488 */ 489 cmpl $0,4(%ebp) 490 je olddiskboot 491 492 /* 493 * We have some form of return address, so this is either the 494 * old diskless netboot code, or the new uniform code. That can 495 * be detected by looking at the 5th argument, if it is 0 496 * we are being booted by the new uniform boot code. 497 */ 498 cmpl $0,24(%ebp) 499 je newboot 500 501 /* 502 * Seems we have been loaded by the old diskless boot code, we 503 * don't stand a chance of running as the diskless structure 504 * changed considerably between the two, so just halt. 505 */ 506 hlt 507 508 /* 509 * We have been loaded by the new uniform boot code. 510 * Let's check the bootinfo version, and if we do not understand 511 * it we return to the loader with a status of 1 to indicate this error 512 */ 513newboot: 514 movl 28(%ebp),%ebx /* &bootinfo.version */ 515 movl BI_VERSION(%ebx),%eax 516 cmpl $1,%eax /* We only understand version 1 */ 517 je 1f 518 movl $1,%eax /* Return status */ 519 leave 520 /* 521 * XXX this returns to our caller's caller (as is required) since 522 * we didn't set up a frame and our caller did. 523 */ 524 ret 525 5261: 527 /* 528 * If we have a kernelname copy it in 529 */ 530 movl BI_KERNELNAME(%ebx),%esi 531 cmpl $0,%esi 532 je 2f /* No kernelname */ 533 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 534 movl $R(_kernelname),%edi 535 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 536 je 1f 537 movb $'/',(%edi) 538 incl %edi 539 decl %ecx 5401: 541 cld 542 rep 543 movsb 544 5452: 546 /* 547 * Determine the size of the boot loader's copy of the bootinfo 548 * struct. This is impossible to do properly because old versions 549 * of the struct don't contain a size field and there are 2 old 550 * versions with the same version number. 551 */ 552 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 553 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 554 je got_bi_size /* no, sizeless version */ 555 movl BI_SIZE(%ebx),%ecx 556got_bi_size: 557 558 /* 559 * Copy the common part of the bootinfo struct 560 */ 561 movl %ebx,%esi 562 movl $R(_bootinfo),%edi 563 cmpl $BOOTINFO_SIZE,%ecx 564 jbe got_common_bi_size 565 movl $BOOTINFO_SIZE,%ecx 566got_common_bi_size: 567 cld 568 rep 569 movsb 570 571#ifdef NFS 572#ifndef BOOTP_NFSV3 573 /* 574 * If we have a nfs_diskless structure copy it in 575 */ 576 movl BI_NFS_DISKLESS(%ebx),%esi 577 cmpl $0,%esi 578 je olddiskboot 579 movl $R(_nfs_diskless),%edi 580 movl $NFSDISKLESS_SIZE,%ecx 581 cld 582 rep 583 movsb 584 movl $R(_nfs_diskless_valid),%edi 585 movl $1,(%edi) 586#endif 587#endif 588 589 /* 590 * The old style disk boot. 591 * (*btext)(howto, bootdev, cyloffset, esym); 592 * Note that the newer boot code just falls into here to pick 593 * up howto and bootdev, cyloffset and esym are no longer used 594 */ 595olddiskboot: 596 movl 8(%ebp),%eax 597 movl %eax,R(_boothowto) 598 movl 12(%ebp),%eax 599 movl %eax,R(_bootdev) 600 601#if defined(USERCONFIG_BOOT) && defined(USERCONFIG) 602 movl $0x10200, %esi 603 movl $R(_userconfig_from_boot),%edi 604 movl $512,%ecx 605 cld 606 rep 607 movsb 608#endif /* USERCONFIG_BOOT */ 609 610 ret 611 612 613/********************************************************************** 614 * 615 * Identify the CPU and initialize anything special about it 616 * 617 */ 618identify_cpu: 619 620 /* Try to toggle alignment check flag; does not exist on 386. */ 621 pushfl 622 popl %eax 623 movl %eax,%ecx 624 orl $PSL_AC,%eax 625 pushl %eax 626 popfl 627 pushfl 628 popl %eax 629 xorl %ecx,%eax 630 andl $PSL_AC,%eax 631 pushl %ecx 632 popfl 633 634 testl %eax,%eax 635 jnz try486 636 637 /* NexGen CPU does not have aligment check flag. */ 638 pushfl 639 movl $0x5555, %eax 640 xorl %edx, %edx 641 movl $2, %ecx 642 clc 643 divl %ecx 644 jz trynexgen 645 popfl 646 movl $CPU_386,R(_cpu) 647 jmp 3f 648 649trynexgen: 650 popfl 651 movl $CPU_NX586,R(_cpu) 652 movl $0x4778654e,R(_cpu_vendor) # store vendor string 653 movl $0x72446e65,R(_cpu_vendor+4) 654 movl $0x6e657669,R(_cpu_vendor+8) 655 movl $0,R(_cpu_vendor+12) 656 jmp 3f 657 658try486: /* Try to toggle identification flag; does not exist on early 486s. */ 659 pushfl 660 popl %eax 661 movl %eax,%ecx 662 xorl $PSL_ID,%eax 663 pushl %eax 664 popfl 665 pushfl 666 popl %eax 667 xorl %ecx,%eax 668 andl $PSL_ID,%eax 669 pushl %ecx 670 popfl 671 672 testl %eax,%eax 673 jnz trycpuid 674 movl $CPU_486,R(_cpu) 675 676 /* 677 * Check Cyrix CPU 678 * Cyrix CPUs do not change the undefined flags following 679 * execution of the divide instruction which divides 5 by 2. 680 * 681 * Note: CPUID is enabled on M2, so it passes another way. 682 */ 683 pushfl 684 movl $0x5555, %eax 685 xorl %edx, %edx 686 movl $2, %ecx 687 clc 688 divl %ecx 689 jnc trycyrix 690 popfl 691 jmp 3f /* You may use Intel CPU. */ 692 693trycyrix: 694 popfl 695 /* 696 * IBM Bluelighting CPU also doesn't change the undefined flags. 697 * Because IBM doesn't disclose the information for Bluelighting 698 * CPU, we couldn't distinguish it from Cyrix's (including IBM 699 * brand of Cyrix CPUs). 700 */ 701 movl $0x69727943,R(_cpu_vendor) # store vendor string 702 movl $0x736e4978,R(_cpu_vendor+4) 703 movl $0x64616574,R(_cpu_vendor+8) 704 jmp 3f 705 706trycpuid: /* Use the `cpuid' instruction. */ 707 xorl %eax,%eax 708 .byte 0x0f,0xa2 # cpuid 0 709 movl %eax,R(_cpu_high) # highest capability 710 movl %ebx,R(_cpu_vendor) # store vendor string 711 movl %edx,R(_cpu_vendor+4) 712 movl %ecx,R(_cpu_vendor+8) 713 movb $0,R(_cpu_vendor+12) 714 715 movl $1,%eax 716 .byte 0x0f,0xa2 # cpuid 1 717 movl %eax,R(_cpu_id) # store cpu_id 718 movl %edx,R(_cpu_feature) # store cpu_feature 719 rorl $8,%eax # extract family type 720 andl $15,%eax 721 cmpl $5,%eax 722 jae 1f 723 724 /* less than Pentium; must be 486 */ 725 movl $CPU_486,R(_cpu) 726 jmp 3f 7271: 728 /* a Pentium? */ 729 cmpl $5,%eax 730 jne 2f 731 movl $CPU_586,R(_cpu) 732 jmp 3f 7332: 734 /* Greater than Pentium...call it a Pentium Pro */ 735 movl $CPU_686,R(_cpu) 7363: 737 ret 738 739 740/********************************************************************** 741 * 742 * Create the first page directory and its page tables. 743 * 744 */ 745 746create_pagetables: 747 748 testl $CPUID_PGE, R(_cpu_feature) 749 jz 1f 750 movl %cr4, %eax 751 orl $CR4_PGE, %eax 752 movl %eax, %cr4 7531: 754 755/* Find end of kernel image (rounded up to a page boundary). */ 756 movl $R(_end),%esi 757 758/* include symbols in "kernel image" if they are loaded and useful */ 759#ifdef DDB 760 movl R(_bootinfo+BI_ESYMTAB),%edi 761 testl %edi,%edi 762 je over_symalloc 763 movl %edi,%esi 764 movl $KERNBASE,%edi 765 addl %edi,R(_bootinfo+BI_SYMTAB) 766 addl %edi,R(_bootinfo+BI_ESYMTAB) 767over_symalloc: 768#endif 769 770 addl $PAGE_MASK,%esi 771 andl $~PAGE_MASK,%esi 772 movl %esi,R(_KERNend) /* save end of kernel */ 773 movl %esi,R(physfree) /* next free page is at end of kernel */ 774 775/* Allocate Kernel Page Tables */ 776 ALLOCPAGES(NKPT) 777 movl %esi,R(_KPTphys) 778 779/* Allocate Page Table Directory */ 780 ALLOCPAGES(1) 781 movl %esi,R(_IdlePTD) 782 783/* Allocate UPAGES */ 784 ALLOCPAGES(UPAGES) 785 movl %esi,R(p0upa) 786 addl $KERNBASE, %esi 787 movl %esi, R(_proc0paddr) 788 789#ifdef VM86 790 ALLOCPAGES(4) /* IOPAGES + ext + stack */ 791 movl %esi,R(_vm86pa) 792 addl $KERNBASE, %esi 793 movl %esi, R(_vm86paddr) 794#endif /* VM86 */ 795 796#ifdef SMP 797/* Allocate cpu0's private data page */ 798 ALLOCPAGES(1) 799 movl %esi,R(cpu0pp) 800 addl $KERNBASE, %esi 801 movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 802 803/* Allocate cpu0's private page table for mapping priv page, apic, etc */ 804 ALLOCPAGES(1) 805 movl %esi,R(cpu0pt) 806 addl $KERNBASE, %esi 807 movl %esi, R(_cpu0prvpt) /* relocated to KVM space */ 808#endif /* SMP */ 809 810/* Map read-only from zero to the end of the kernel text section */ 811 xorl %eax, %eax 812#ifdef BDE_DEBUGGER 813/* If the debugger is present, actually map everything read-write. */ 814 cmpl $0,R(_bdb_exists) 815 jne map_read_write 816#endif 817 xorl %edx,%edx 818 819#if !defined(SMP) 820 testl $CPUID_PGE, R(_cpu_feature) 821 jz 2f 822 orl $PG_G,%edx 823#endif 824 8252: movl $R(_etext),%ecx 826 addl $PAGE_MASK,%ecx 827 shrl $PAGE_SHIFT,%ecx 828 fillkptphys(%edx) 829 830/* Map read-write, data, bss and symbols */ 831 movl $R(_etext),%eax 832 addl $PAGE_MASK, %eax 833 andl $~PAGE_MASK, %eax 834map_read_write: 835 movl $PG_RW,%edx 836#if !defined(SMP) 837 testl $CPUID_PGE, R(_cpu_feature) 838 jz 1f 839 orl $PG_G,%edx 840#endif 841 8421: movl R(_KERNend),%ecx 843 subl %eax,%ecx 844 shrl $PAGE_SHIFT,%ecx 845 fillkptphys(%edx) 846 847/* Map page directory. */ 848 movl R(_IdlePTD), %eax 849 movl $1, %ecx 850 fillkptphys($PG_RW) 851 852/* Map proc0's UPAGES in the physical way ... */ 853 movl R(p0upa), %eax 854 movl $UPAGES, %ecx 855 fillkptphys($PG_RW) 856 857/* Map ISA hole */ 858 movl $ISA_HOLE_START, %eax 859 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 860 fillkptphys($PG_RW) 861 862#ifdef VM86 863/* Map space for the vm86 region */ 864 movl R(_vm86pa), %eax 865 movl $4, %ecx 866 fillkptphys($PG_RW) 867 868/* Map page 0 into the vm86 page table */ 869 movl $0, %eax 870 movl $0, %ebx 871 movl $1, %ecx 872 fillkpt(R(_vm86pa), $PG_RW|PG_U) 873 874/* ...likewise for the ISA hole */ 875 movl $ISA_HOLE_START, %eax 876 movl $ISA_HOLE_START>>PAGE_SHIFT, %ebx 877 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 878 fillkpt(R(_vm86pa), $PG_RW|PG_U) 879#endif /* VM86 */ 880 881#ifdef SMP 882/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 883 movl R(cpu0pp), %eax 884 movl $1, %ecx 885 fillkptphys($PG_RW) 886 887/* Map cpu0's private page table into global kmem FWIW */ 888 movl R(cpu0pt), %eax 889 movl $1, %ecx 890 fillkptphys($PG_RW) 891 892/* Map the private page into the private page table into private space */ 893 movl R(cpu0pp), %eax 894 movl $0, %ebx /* pte offset = 0 */ 895 movl $1, %ecx /* one private page coming right up */ 896 fillkpt(R(cpu0pt), $PG_RW) 897 898/* Map the page table page into private space */ 899 movl R(cpu0pt), %eax 900 movl $1, %ebx /* pte offset = 1 */ 901 movl $1, %ecx /* one private pt coming right up */ 902 fillkpt(R(cpu0pt), $PG_RW) 903 904/* ... and put the page table table in the pde. */ 905 movl R(cpu0pt), %eax 906 movl $MPPTDI, %ebx 907 movl $1, %ecx 908 fillkpt(R(_IdlePTD), $PG_RW) 909 910/* Fakeup VA for the local apic to allow early traps. */ 911 ALLOCPAGES(1) 912 movl %esi, %eax 913 movl $2, %ebx /* pte offset = 2 */ 914 movl $1, %ecx /* one private pt coming right up */ 915 fillkpt(R(cpu0pt), $PG_RW) 916 917/* Initialize mp lock to allow early traps */ 918 movl $1, R(_mp_lock) 919 920/* Initialize my_idlePTD to IdlePTD */ 921 movl R(cpu0pp), %eax 922 movl R(_IdlePTD), %ecx 923 movl %ecx,GD_MY_IDLEPTD(%eax) 924 925#endif /* SMP */ 926 927/* install a pde for temporary double map of bottom of VA */ 928 movl R(_KPTphys), %eax 929 xorl %ebx, %ebx 930 movl $1, %ecx 931 fillkpt(R(_IdlePTD), $PG_RW) 932 933/* install pde's for pt's */ 934 movl R(_KPTphys), %eax 935 movl $KPTDI, %ebx 936 movl $NKPT, %ecx 937 fillkpt(R(_IdlePTD), $PG_RW) 938 939/* install a pde recursively mapping page directory as a page table */ 940 movl R(_IdlePTD), %eax 941 movl $PTDPTDI, %ebx 942 movl $1,%ecx 943 fillkpt(R(_IdlePTD), $PG_RW) 944 945 ret 946 947#ifdef BDE_DEBUGGER 948bdb_prepare_paging: 949 cmpl $0,R(_bdb_exists) 950 je bdb_prepare_paging_exit 951 952 subl $6,%esp 953 954 /* 955 * Copy and convert debugger entries from the bootstrap gdt and idt 956 * to the kernel gdt and idt. Everything is still in low memory. 957 * Tracing continues to work after paging is enabled because the 958 * low memory addresses remain valid until everything is relocated. 959 * However, tracing through the setidt() that initializes the trace 960 * trap will crash. 961 */ 962 sgdt (%esp) 963 movl 2(%esp),%esi /* base address of bootstrap gdt */ 964 movl $R(_gdt),%edi 965 movl %edi,2(%esp) /* prepare to load kernel gdt */ 966 movl $8*18/4,%ecx 967 cld 968 rep /* copy gdt */ 969 movsl 970 movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 971 movb $0x92,-8+5(%edi) 972 lgdt (%esp) 973 974 sidt (%esp) 975 movl 2(%esp),%esi /* base address of current idt */ 976 movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 977 movw 8(%esi),%ax 978 movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 979 movl 8+2(%esi),%eax 980 movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 981 movl 24+4(%esi),%eax /* same for bpt descriptor */ 982 movw 24(%esi),%ax 983 movl %eax,R(bdb_bpt_ljmp+1) 984 movl 24+2(%esi),%eax 985 movw %ax,R(bdb_bpt_ljmp+5) 986 movl $R(_idt),%edi 987 movl %edi,2(%esp) /* prepare to load kernel idt */ 988 movl $8*4/4,%ecx 989 cld 990 rep /* copy idt */ 991 movsl 992 lidt (%esp) 993 994 addl $6,%esp 995 996bdb_prepare_paging_exit: 997 ret 998 999/* Relocate debugger gdt entries and gdt and idt pointers. */ 1000bdb_commit_paging: 1001 cmpl $0,_bdb_exists 1002 je bdb_commit_paging_exit 1003 1004 movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 1005 movl $9,%ecx 1006reloc_gdt: 1007 movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 1008 addl $8,%eax /* now KERNBASE>>24 */ 1009 loop reloc_gdt 1010 1011 subl $6,%esp 1012 sgdt (%esp) 1013 addl $KERNBASE,2(%esp) 1014 lgdt (%esp) 1015 sidt (%esp) 1016 addl $KERNBASE,2(%esp) 1017 lidt (%esp) 1018 addl $6,%esp 1019 1020 int $3 1021 1022bdb_commit_paging_exit: 1023 ret 1024 1025#endif /* BDE_DEBUGGER */ 1026