locore.s revision 26267
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 1.87 1997/05/15 19:12:56 tegge 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#include "opt_smp_privpages.h" 51#include "opt_serial.h" 52 53#include <sys/errno.h> 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#if defined(SMP) && defined(SMP_PRIVPAGES) 64#include <machine/apic.h> 65#endif /* SMP && PRIVPAGES */ 66 67#include "assym.s" 68 69/* 70 * XXX 71 * 72 * Note: This version greatly munged to avoid various assembler errors 73 * that may be fixed in newer versions of gas. Perhaps newer versions 74 * will have more pleasant appearance. 75 */ 76 77/* 78 * PTmap is recursive pagemap at top of virtual address space. 79 * Within PTmap, the page directory can be found (third indirection). 80 */ 81 .globl _PTmap,_PTD,_PTDpde 82 .set _PTmap,(PTDPTDI << PDRSHIFT) 83 .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 84 .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 85 86/* 87 * APTmap, APTD is the alternate recursive pagemap. 88 * It's used when modifying another process's page tables. 89 */ 90 .globl _APTmap,_APTD,_APTDpde 91 .set _APTmap,APTDPTDI << PDRSHIFT 92 .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 93 .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 94 95/* 96 * Globals 97 */ 98 .data 99 ALIGN_DATA /* just to be sure */ 100 101 .globl HIDENAME(tmpstk) 102 .space 0x2000 /* space for tmpstk - temporary stack */ 103HIDENAME(tmpstk): 104 105 .globl _boothowto,_bootdev 106 107 .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 108 .globl _cpu_high, _cpu_feature 109 110_cpu: .long 0 /* are we 386, 386sx, or 486 */ 111_cpu_id: .long 0 /* stepping ID */ 112_cpu_high: .long 0 /* highest arg to CPUID */ 113_cpu_feature: .long 0 /* features */ 114_cpu_vendor: .space 20 /* CPU origin code */ 115_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 116 117_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 118physfree: .long 0 /* phys addr of next free page */ 119 120#if defined(SMP) && defined(SMP_PRIVPAGES) 121cpu0pp: .long 0 /* phys addr cpu0 private pg */ 122cpu0pt: .long 0 /* phys addr cpu0 private pt */ 123 124 .globl _cpu0prvpage,_cpu0prvpt 125_cpu0prvpage: .long 0 /* relocated version */ 126_cpu0prvpt: .long 0 /* relocated version */ 127#endif /* SMP && PRIVPAGES */ 128 129 .globl _IdlePTD 130_IdlePTD: .long 0 /* phys addr of kernel PTD */ 131 132_KPTphys: .long 0 /* phys addr of kernel page tables */ 133 134 .globl _proc0paddr 135_proc0paddr: .long 0 /* address of proc 0 address space */ 136p0upa: .long 0 /* phys addr of proc0's UPAGES */ 137 138#ifdef BDE_DEBUGGER 139 .globl _bdb_exists /* flag to indicate BDE debugger is present */ 140_bdb_exists: .long 0 141#endif 142 143 144/********************************************************************** 145 * 146 * Some handy macros 147 * 148 */ 149 150#define R(foo) ((foo)-KERNBASE) 151 152#define ALLOCPAGES(foo) \ 153 movl R(physfree), %esi ; \ 154 movl $((foo)*PAGE_SIZE), %eax ; \ 155 addl %esi, %eax ; \ 156 movl %eax, R(physfree) ; \ 157 movl %esi, %edi ; \ 158 movl $((foo)*PAGE_SIZE),%ecx ; \ 159 xorl %eax,%eax ; \ 160 cld ; \ 161 rep ; \ 162 stosb 163 164/* 165 * fillkpt 166 * eax = page frame address 167 * ebx = index into page table 168 * ecx = how many pages to map 169 * base = base address of page dir/table 170 * prot = protection bits 171 */ 172#define fillkpt(base, prot) \ 173 shll $2,%ebx ; \ 174 addl base,%ebx ; \ 175 orl $PG_V,%eax ; \ 176 orl prot,%eax ; \ 1771: movl %eax,(%ebx) ; \ 178 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 179 addl $4,%ebx ; /* next pte */ \ 180 loop 1b 181 182/* 183 * fillkptphys(prot) 184 * eax = physical address 185 * ecx = how many pages to map 186 * prot = protection bits 187 */ 188#define fillkptphys(prot) \ 189 movl %eax, %ebx ; \ 190 shrl $PAGE_SHIFT, %ebx ; \ 191 fillkpt(R(_KPTphys), prot) 192 193 .text 194/********************************************************************** 195 * 196 * This is where the bootblocks start us, set the ball rolling... 197 * 198 */ 199NON_GPROF_ENTRY(btext) 200 201#ifdef PC98 202 jmp 1f 203 .globl _pc98_system_parameter 204 .org 0x400 205_pc98_system_parameter: 206 .space 0x240 /* BIOS parameter block */ 2071: 208 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 209 movl $0xa1000,%esi 210 movl $0x100000,%edi 211 movl $0x0630,%ecx 212 cld 213 rep 214 movsb 215#else /* IBM-PC */ 216#ifdef BDE_DEBUGGER 217#ifdef BIOS_STEALS_3K 218 cmpl $0x0375c339,0x95504 219#else 220 cmpl $0x0375c339,0x96104 /* XXX - debugger signature */ 221#endif 222 jne 1f 223 movb $1,R(_bdb_exists) 2241: 225#endif 226 227/* Tell the bios to warmboot next time */ 228 movw $0x1234,0x472 229#endif /* PC98 */ 230 231/* Set up a real frame in case the double return in newboot is executed. */ 232 pushl %ebp 233 movl %esp, %ebp 234 235/* Don't trust what the BIOS gives for eflags. */ 236 pushl $PSL_KERNEL 237 popfl 238 239/* 240 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 241 * to set %cs, %ds, %es and %ss. 242 */ 243 mov %ds, %ax 244 mov %ax, %fs 245 mov %ax, %gs 246 247 call recover_bootinfo 248 249/* Get onto a stack that we can trust. */ 250/* 251 * XXX this step is delayed in case recover_bootinfo needs to return via 252 * the old stack, but it need not be, since recover_bootinfo actually 253 * returns via the old frame. 254 */ 255 movl $R(HIDENAME(tmpstk)),%esp 256 257#ifdef PC98 258 testb $0x02,0x100620 /* pc98_machine_type & M_EPSON_PC98 */ 259 jz 3f 260 cmpb $0x0b,0x100624 /* epson_machine_id <= 0x0b */ 261 ja 3f 262 263 /* count up memory */ 264 movl $0x100000,%eax /* next, talley remaining memory */ 265 movl $0xFFF-0x100,%ecx 2661: movl 0(%eax),%ebx /* save location to check */ 267 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 268 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 269 jne 2f 270 movl %ebx,0(%eax) /* restore memory */ 271 addl $PAGE_SIZE,%eax 272 loop 1b 2732: subl $0x100000,%eax 274 shrl $17,%eax 275 movb %al,0x100401 2763: 277#endif 278 279 call identify_cpu 280 281/* clear bss */ 282/* 283 * XXX this should be done a little earlier. 284 * 285 * XXX we don't check that there is memory for our bss and page tables 286 * before using it. 287 * 288 * XXX the boot program somewhat bogusly clears the bss. We still have 289 * to do it in case we were unzipped by kzipboot. Then the boot program 290 * only clears kzipboot's bss. 291 * 292 * XXX the gdt and idt are still somewhere in the boot program. We 293 * depend on the convention that the boot program is below 1MB and we 294 * are above 1MB to keep the gdt and idt away from the bss and page 295 * tables. The idt is only used if BDE_DEBUGGER is enabled. 296 */ 297 movl $R(_end),%ecx 298 movl $R(_edata),%edi 299 subl %edi,%ecx 300 xorl %eax,%eax 301 cld 302 rep 303 stosb 304 305#if NAPM > 0 306/* 307 * XXX it's not clear that APM can live in the current environonment. 308 * Only pc-relative addressing works. 309 */ 310 call _apm_setup 311#endif 312 313 call create_pagetables 314 315#ifdef BDE_DEBUGGER 316/* 317 * Adjust as much as possible for paging before enabling paging so that the 318 * adjustments can be traced. 319 */ 320 call bdb_prepare_paging 321#endif 322 323/* Now enable paging */ 324 movl R(_IdlePTD), %eax 325 movl %eax,%cr3 /* load ptd addr into mmu */ 326 movl %cr0,%eax /* get control word */ 327 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 328 movl %eax,%cr0 /* and let's page NOW! */ 329 330#ifdef BDE_DEBUGGER 331/* 332 * Complete the adjustments for paging so that we can keep tracing through 333 * initi386() after the low (physical) addresses for the gdt and idt become 334 * invalid. 335 */ 336 call bdb_commit_paging 337#endif 338 339 pushl $begin /* jump to high virtualized address */ 340 ret 341 342/* now running relocated at KERNBASE where the system is linked to run */ 343begin: 344 /* set up bootstrap stack */ 345 movl _proc0paddr,%esp /* location of in-kernel pages */ 346 addl $UPAGES*PAGE_SIZE,%esp /* bootstrap stack end location */ 347 xorl %eax,%eax /* mark end of frames */ 348 movl %eax,%ebp 349 movl _proc0paddr,%eax 350 movl _IdlePTD, %esi 351 movl %esi,PCB_CR3(%eax) 352 353 movl physfree, %esi 354 pushl %esi /* value of first for init386(first) */ 355 call _init386 /* wire 386 chip for unix operation */ 356 popl %esi 357 358 .globl __ucodesel,__udatasel 359 360 pushl $0 /* unused */ 361 pushl __udatasel /* ss */ 362 pushl $0 /* esp - filled in by execve() */ 363 pushl $PSL_USER /* eflags (IOPL 0, int enab) */ 364 pushl __ucodesel /* cs */ 365 pushl $0 /* eip - filled in by execve() */ 366 subl $(12*4),%esp /* space for rest of registers */ 367 368 pushl %esp /* call main with frame pointer */ 369 call _main /* autoconfiguration, mountroot etc */ 370 371 hlt /* never returns to here */ 372 373/* 374 * When starting init, call this to configure the process for user 375 * mode. This will be inherited by other processes. 376 */ 377NON_GPROF_ENTRY(prepare_usermode) 378 /* 379 * Now we've run main() and determined what cpu-type we are, we can 380 * enable write protection and alignment checking on i486 cpus and 381 * above. 382 */ 383#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) 384 cmpl $CPUCLASS_386,_cpu_class 385 je 1f 386 movl %cr0,%eax /* get control word */ 387 orl $CR0_WP|CR0_AM,%eax /* enable i486 features */ 388 movl %eax,%cr0 /* and do it */ 3891: 390#endif 391 /* 392 * on return from main(), we are process 1 393 * set up address space and stack so that we can 'return' to user mode 394 */ 395 movl __ucodesel,%eax 396 movl __udatasel,%ecx 397 398#if 0 399 movl %cx,%ds 400#endif 401 movl %cx,%es 402 movl %ax,%fs /* double map cs to fs */ 403 movl %cx,%gs /* and ds to gs */ 404 ret /* goto user! */ 405 406 407#define LCALL(x,y) .byte 0x9a ; .long y ; .word x 408 409/* 410 * Signal trampoline, copied to top of user stack 411 */ 412NON_GPROF_ENTRY(sigcode) 413 call SIGF_HANDLER(%esp) 414 lea SIGF_SC(%esp),%eax /* scp (the call may have clobbered the */ 415 /* copy at 8(%esp)) */ 416 pushl %eax 417 pushl %eax /* junk to fake return address */ 418 movl $SYS_sigreturn,%eax /* sigreturn() */ 419 LCALL(0x7,0) /* enter kernel with args on stack */ 420 hlt /* never gets here */ 421 ALIGN_TEXT 422_esigcode: 423 424 .data 425 .globl _szsigcode 426_szsigcode: 427 .long _esigcode-_sigcode 428 .text 429 430/********************************************************************** 431 * 432 * Recover the bootinfo passed to us from the boot program 433 * 434 */ 435recover_bootinfo: 436 /* 437 * This code is called in different ways depending on what loaded 438 * and started the kernel. This is used to detect how we get the 439 * arguments from the other code and what we do with them. 440 * 441 * Old disk boot blocks: 442 * (*btext)(howto, bootdev, cyloffset, esym); 443 * [return address == 0, and can NOT be returned to] 444 * [cyloffset was not supported by the FreeBSD boot code 445 * and always passed in as 0] 446 * [esym is also known as total in the boot code, and 447 * was never properly supported by the FreeBSD boot code] 448 * 449 * Old diskless netboot code: 450 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 451 * [return address != 0, and can NOT be returned to] 452 * If we are being booted by this code it will NOT work, 453 * so we are just going to halt if we find this case. 454 * 455 * New uniform boot code: 456 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 457 * [return address != 0, and can be returned to] 458 * 459 * There may seem to be a lot of wasted arguments in here, but 460 * that is so the newer boot code can still load very old kernels 461 * and old boot code can load new kernels. 462 */ 463 464 /* 465 * The old style disk boot blocks fake a frame on the stack and 466 * did an lret to get here. The frame on the stack has a return 467 * address of 0. 468 */ 469 cmpl $0,4(%ebp) 470 je olddiskboot 471 472 /* 473 * We have some form of return address, so this is either the 474 * old diskless netboot code, or the new uniform code. That can 475 * be detected by looking at the 5th argument, if it is 0 476 * we are being booted by the new uniform boot code. 477 */ 478 cmpl $0,24(%ebp) 479 je newboot 480 481 /* 482 * Seems we have been loaded by the old diskless boot code, we 483 * don't stand a chance of running as the diskless structure 484 * changed considerably between the two, so just halt. 485 */ 486 hlt 487 488 /* 489 * We have been loaded by the new uniform boot code. 490 * Let's check the bootinfo version, and if we do not understand 491 * it we return to the loader with a status of 1 to indicate this error 492 */ 493newboot: 494 movl 28(%ebp),%ebx /* &bootinfo.version */ 495 movl BI_VERSION(%ebx),%eax 496 cmpl $1,%eax /* We only understand version 1 */ 497 je 1f 498 movl $1,%eax /* Return status */ 499 leave 500 /* 501 * XXX this returns to our caller's caller (as is required) since 502 * we didn't set up a frame and our caller did. 503 */ 504 ret 505 5061: 507 /* 508 * If we have a kernelname copy it in 509 */ 510 movl BI_KERNELNAME(%ebx),%esi 511 cmpl $0,%esi 512 je 2f /* No kernelname */ 513 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 514 movl $R(_kernelname),%edi 515 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 516 je 1f 517 movb $'/',(%edi) 518 incl %edi 519 decl %ecx 5201: 521 cld 522 rep 523 movsb 524 5252: 526 /* 527 * Determine the size of the boot loader's copy of the bootinfo 528 * struct. This is impossible to do properly because old versions 529 * of the struct don't contain a size field and there are 2 old 530 * versions with the same version number. 531 */ 532 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 533 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 534 je got_bi_size /* no, sizeless version */ 535 movl BI_SIZE(%ebx),%ecx 536got_bi_size: 537 538 /* 539 * Copy the common part of the bootinfo struct 540 */ 541 movl %ebx,%esi 542 movl $R(_bootinfo),%edi 543 cmpl $BOOTINFO_SIZE,%ecx 544 jbe got_common_bi_size 545 movl $BOOTINFO_SIZE,%ecx 546got_common_bi_size: 547 cld 548 rep 549 movsb 550 551#ifdef NFS 552#ifndef BOOTP_NFSV3 553 /* 554 * If we have a nfs_diskless structure copy it in 555 */ 556 movl BI_NFS_DISKLESS(%ebx),%esi 557 cmpl $0,%esi 558 je olddiskboot 559 movl $R(_nfs_diskless),%edi 560 movl $NFSDISKLESS_SIZE,%ecx 561 cld 562 rep 563 movsb 564 movl $R(_nfs_diskless_valid),%edi 565 movl $1,(%edi) 566#endif 567#endif 568 569 /* 570 * The old style disk boot. 571 * (*btext)(howto, bootdev, cyloffset, esym); 572 * Note that the newer boot code just falls into here to pick 573 * up howto and bootdev, cyloffset and esym are no longer used 574 */ 575olddiskboot: 576 movl 8(%ebp),%eax 577 movl %eax,R(_boothowto) 578 movl 12(%ebp),%eax 579 movl %eax,R(_bootdev) 580 581#if defined(USERCONFIG_BOOT) && defined(USERCONFIG) 582#ifdef PC98 583 movl $0x90200, %esi 584#else 585 movl $0x10200, %esi 586#endif 587 movl $R(_userconfig_from_boot),%edi 588 movl $512,%ecx 589 cld 590 rep 591 movsb 592#endif /* USERCONFIG_BOOT */ 593 594 ret 595 596 597/********************************************************************** 598 * 599 * Identify the CPU and initialize anything special about it 600 * 601 */ 602identify_cpu: 603 604 /* Try to toggle alignment check flag; does not exist on 386. */ 605 pushfl 606 popl %eax 607 movl %eax,%ecx 608 orl $PSL_AC,%eax 609 pushl %eax 610 popfl 611 pushfl 612 popl %eax 613 xorl %ecx,%eax 614 andl $PSL_AC,%eax 615 pushl %ecx 616 popfl 617 618 testl %eax,%eax 619 jnz try486 620 621 /* NexGen CPU does not have aligment check flag. */ 622 pushfl 623 movl $0x5555, %eax 624 xorl %edx, %edx 625 movl $2, %ecx 626 clc 627 divl %ecx 628 jz trynexgen 629 popfl 630 movl $CPU_386,R(_cpu) 631 jmp 3f 632 633trynexgen: 634 movl $CPU_NX586,R(_cpu) 635 movl $0x4778654e,R(_cpu_vendor) # store vendor string 636 movl $0x72446e65,R(_cpu_vendor+4) 637 movl $0x6e657669,R(_cpu_vendor+8) 638 movl $0,R(_cpu_vendor+12) 639 jmp 3f 640 641try486: /* Try to toggle identification flag; does not exist on early 486s. */ 642 pushfl 643 popl %eax 644 movl %eax,%ecx 645 xorl $PSL_ID,%eax 646 pushl %eax 647 popfl 648 pushfl 649 popl %eax 650 xorl %ecx,%eax 651 andl $PSL_ID,%eax 652 pushl %ecx 653 popfl 654 655 testl %eax,%eax 656 jnz trycpuid 657 movl $CPU_486,R(_cpu) 658 659 /* 660 * Check Cyrix CPU 661 * Cyrix CPUs do not change the undefined flags following 662 * execution of the divide instruction which divides 5 by 2. 663 * 664 * Note: CPUID is enabled on M2, so it passes another way. 665 */ 666 pushfl 667 movl $0x5555, %eax 668 xorl %edx, %edx 669 movl $2, %ecx 670 clc 671 divl %ecx 672 jnc trycyrix 673 popfl 674 jmp 3f /* You may use Intel CPU. */ 675 676trycyrix: 677 popfl 678 /* 679 * IBM Bluelighting CPU also doesn't change the undefined flags. 680 * Because IBM doesn't disclose the information for Bluelighting 681 * CPU, we couldn't distinguish it from Cyrix's (including IBM 682 * brand of Cyrix CPUs). 683 */ 684 movl $0x69727943,R(_cpu_vendor) # store vendor string 685 movl $0x736e4978,R(_cpu_vendor+4) 686 movl $0x64616574,R(_cpu_vendor+8) 687 jmp 3f 688 689trycpuid: /* Use the `cpuid' instruction. */ 690 xorl %eax,%eax 691 .byte 0x0f,0xa2 # cpuid 0 692 movl %eax,R(_cpu_high) # highest capability 693 movl %ebx,R(_cpu_vendor) # store vendor string 694 movl %edx,R(_cpu_vendor+4) 695 movl %ecx,R(_cpu_vendor+8) 696 movb $0,R(_cpu_vendor+12) 697 698 movl $1,%eax 699 .byte 0x0f,0xa2 # cpuid 1 700 movl %eax,R(_cpu_id) # store cpu_id 701 movl %edx,R(_cpu_feature) # store cpu_feature 702 rorl $8,%eax # extract family type 703 andl $15,%eax 704 cmpl $5,%eax 705 jae 1f 706 707 /* less than Pentium; must be 486 */ 708 movl $CPU_486,R(_cpu) 709 jmp 3f 7101: 711 /* a Pentium? */ 712 cmpl $5,%eax 713 jne 2f 714 movl $CPU_586,R(_cpu) 715 jmp 3f 7162: 717 /* Greater than Pentium...call it a Pentium Pro */ 718 movl $CPU_686,R(_cpu) 7193: 720 ret 721 722 723/********************************************************************** 724 * 725 * Create the first page directory and its page tables. 726 * 727 */ 728 729create_pagetables: 730 731 testl $CPUID_PGE, R(_cpu_feature) 732 jz 1f 733 movl %cr4, %eax 734 orl $CR4_PGE, %eax 735 movl %eax, %cr4 7361: 737 738/* Find end of kernel image (rounded up to a page boundary). */ 739 movl $R(_end),%esi 740 741/* include symbols in "kernel image" if they are loaded and useful */ 742#ifdef DDB 743 movl R(_bootinfo+BI_ESYMTAB),%edi 744 testl %edi,%edi 745 je over_symalloc 746 movl %edi,%esi 747 movl $KERNBASE,%edi 748 addl %edi,R(_bootinfo+BI_SYMTAB) 749 addl %edi,R(_bootinfo+BI_ESYMTAB) 750over_symalloc: 751#endif 752 753 addl $PAGE_MASK,%esi 754 andl $~PAGE_MASK,%esi 755 movl %esi,R(_KERNend) /* save end of kernel */ 756 movl %esi,R(physfree) /* next free page is at end of kernel */ 757 758/* Allocate Kernel Page Tables */ 759 ALLOCPAGES(NKPT) 760 movl %esi,R(_KPTphys) 761 762/* Allocate Page Table Directory */ 763 ALLOCPAGES(1) 764 movl %esi,R(_IdlePTD) 765 766/* Allocate UPAGES */ 767 ALLOCPAGES(UPAGES) 768 movl %esi,R(p0upa) 769 addl $KERNBASE, %esi 770 movl %esi, R(_proc0paddr) 771 772#if defined(SMP) && defined(SMP_PRIVPAGES) 773/* Allocate cpu0's private data page */ 774 ALLOCPAGES(1) 775 movl %esi,R(cpu0pp) 776 addl $KERNBASE, %esi 777 movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 778 779/* Allocate cpu0's private page table for mapping priv page, apic, etc */ 780 ALLOCPAGES(1) 781 movl %esi,R(cpu0pt) 782 addl $KERNBASE, %esi 783 movl %esi, R(_cpu0prvpt) /* relocated to KVM space */ 784#endif /* SMP && SMP_PRIVPAGES */ 785 786/* Map read-only from zero to the end of the kernel text section */ 787 xorl %eax, %eax 788#ifdef BDE_DEBUGGER 789/* If the debugger is present, actually map everything read-write. */ 790 cmpl $0,R(_bdb_exists) 791 jne map_read_write 792#endif 793 xorl %edx,%edx 794 testl $CPUID_PGE, R(_cpu_feature) 795 jz 2f 796 orl $PG_G,%edx 797 7982: movl $R(_etext),%ecx 799 addl $PAGE_MASK,%ecx 800 shrl $PAGE_SHIFT,%ecx 801 fillkptphys(%edx) 802 803/* Map read-write, data, bss and symbols */ 804 movl $R(_etext),%eax 805 addl $PAGE_MASK, %eax 806 andl $~PAGE_MASK, %eax 807map_read_write: 808 movl $PG_RW,%edx 809 testl $CPUID_PGE, R(_cpu_feature) 810 jz 1f 811 orl $PG_G,%edx 812 8131: movl R(_KERNend),%ecx 814 subl %eax,%ecx 815 shrl $PAGE_SHIFT,%ecx 816 fillkptphys(%edx) 817 818/* Map page directory. */ 819 movl R(_IdlePTD), %eax 820 movl $1, %ecx 821 fillkptphys($PG_RW) 822 823/* Map proc0's UPAGES in the physical way ... */ 824 movl R(p0upa), %eax 825 movl $UPAGES, %ecx 826 fillkptphys($PG_RW) 827 828/* Map ISA hole */ 829 movl $ISA_HOLE_START, %eax 830 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 831 fillkptphys($PG_RW) 832 833#if defined(SMP) && defined(SMP_PRIVPAGES) 834/* Map cpu0's private page into global KVM */ 835 movl R(cpu0pp), %eax 836 movl $1, %ecx 837 fillkptphys($PG_RW) 838 839/* Map cpu0's private page table into global KVM */ 840 movl R(cpu0pt), %eax 841 movl $1, %ecx 842 fillkptphys($PG_RW) 843 844/* Map the private page into the private page table (4K @ 0xff80000) */ 845 movl R(cpu0pp), %eax 846 movl $0, %ebx /* pte offset = 0 */ 847 movl $1, %ecx /* one private page coming right up */ 848 fillkpt(R(cpu0pt), $PG_RW) 849 850/* Map the default Local APIC address (4K @ 0xff801000) */ 851 movl $DEFAULT_APIC_BASE, %eax /* XXX just testing.. */ 852 movl $1, %ebx /* pte offset = 1 */ 853 movl $1, %ecx /* Bing! Local APIC appears */ 854 fillkpt(R(cpu0pt), $PG_RW|PG_N) 855 856/* Map the default IO APIC address (4K @ 0xff802000) */ 857 movl $DEFAULT_IO_APIC_BASE, %eax /* XXX just testing.. */ 858 movl $2, %ebx /* pte offset = 2 */ 859 movl $1, %ecx /* Bing! Local APIC appears */ 860 fillkpt(R(cpu0pt), $PG_RW|PG_N) 861 862/* ... and put the page table in the pde. */ 863 movl R(cpu0pt), %eax 864 movl $MPPTDI, %ebx 865 movl $1, %ecx 866 fillkpt(R(_IdlePTD), $PG_RW) 867#endif /* SMP && SMP_PRIVPAGES */ 868 869/* install a pde for temporary double map of bottom of VA */ 870 movl R(_KPTphys), %eax 871 xorl %ebx, %ebx 872 movl $1, %ecx 873 fillkpt(R(_IdlePTD), $PG_RW) 874 875/* install pde's for pt's */ 876 movl R(_KPTphys), %eax 877 movl $KPTDI, %ebx 878 movl $NKPT, %ecx 879 fillkpt(R(_IdlePTD), $PG_RW) 880 881/* install a pde recursively mapping page directory as a page table */ 882 movl R(_IdlePTD), %eax 883 movl $PTDPTDI, %ebx 884 movl $1,%ecx 885 fillkpt(R(_IdlePTD), $PG_RW) 886 887 ret 888 889#ifdef BDE_DEBUGGER 890bdb_prepare_paging: 891 cmpl $0,R(_bdb_exists) 892 je bdb_prepare_paging_exit 893 894 subl $6,%esp 895 896 /* 897 * Copy and convert debugger entries from the bootstrap gdt and idt 898 * to the kernel gdt and idt. Everything is still in low memory. 899 * Tracing continues to work after paging is enabled because the 900 * low memory addresses remain valid until everything is relocated. 901 * However, tracing through the setidt() that initializes the trace 902 * trap will crash. 903 */ 904 sgdt (%esp) 905 movl 2(%esp),%esi /* base address of bootstrap gdt */ 906 movl $R(_gdt),%edi 907 movl %edi,2(%esp) /* prepare to load kernel gdt */ 908 movl $8*18/4,%ecx 909 cld 910 rep /* copy gdt */ 911 movsl 912 movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 913 movb $0x92,-8+5(%edi) 914 lgdt (%esp) 915 916 sidt (%esp) 917 movl 2(%esp),%esi /* base address of current idt */ 918 movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 919 movw 8(%esi),%ax 920 movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 921 movl 8+2(%esi),%eax 922 movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 923 movl 24+4(%esi),%eax /* same for bpt descriptor */ 924 movw 24(%esi),%ax 925 movl %eax,R(bdb_bpt_ljmp+1) 926 movl 24+2(%esi),%eax 927 movw %ax,R(bdb_bpt_ljmp+5) 928 movl $R(_idt),%edi 929 movl %edi,2(%esp) /* prepare to load kernel idt */ 930 movl $8*4/4,%ecx 931 cld 932 rep /* copy idt */ 933 movsl 934 lidt (%esp) 935 936 addl $6,%esp 937 938bdb_prepare_paging_exit: 939 ret 940 941/* Relocate debugger gdt entries and gdt and idt pointers. */ 942bdb_commit_paging: 943 cmpl $0,_bdb_exists 944 je bdb_commit_paging_exit 945 946 movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 947 movl $9,%ecx 948reloc_gdt: 949 movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 950 addl $8,%eax /* now KERNBASE>>24 */ 951 loop reloc_gdt 952 953 subl $6,%esp 954 sgdt (%esp) 955 addl $KERNBASE,2(%esp) 956 lgdt (%esp) 957 sidt (%esp) 958 addl $KERNBASE,2(%esp) 959 lidt (%esp) 960 addl $6,%esp 961 962 int $3 963 964bdb_commit_paging_exit: 965 ret 966 967#endif /* BDE_DEBUGGER */ 968