locore.s revision 69006
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 * $FreeBSD: head/sys/i386/i386/locore.s 69006 2000-11-21 20:16:49Z markm $ 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 "opt_bootp.h" 47#include "opt_nfsroot.h" 48 49#include <sys/syscall.h> 50#include <sys/reboot.h> 51 52#include <machine/asmacros.h> 53#include <machine/cputypes.h> 54#include <machine/psl.h> 55#include <machine/pmap.h> 56#include <machine/specialreg.h> 57 58#include "assym.s" 59 60/* 61 * XXX 62 * 63 * Note: This version greatly munged to avoid various assembler errors 64 * that may be fixed in newer versions of gas. Perhaps newer versions 65 * will have more pleasant appearance. 66 */ 67 68/* 69 * PTmap is recursive pagemap at top of virtual address space. 70 * Within PTmap, the page directory can be found (third indirection). 71 */ 72 .globl _PTmap,_PTD,_PTDpde 73 .set _PTmap,(PTDPTDI << PDRSHIFT) 74 .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 75 .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 76 77/* 78 * APTmap, APTD is the alternate recursive pagemap. 79 * It's used when modifying another process's page tables. 80 */ 81 .globl _APTmap,_APTD,_APTDpde 82 .set _APTmap,APTDPTDI << PDRSHIFT 83 .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 84 .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 85 86/* 87 * Globals 88 */ 89 .data 90 ALIGN_DATA /* just to be sure */ 91 92 .globl HIDENAME(tmpstk) 93 .space 0x2000 /* space for tmpstk - temporary stack */ 94HIDENAME(tmpstk): 95 96 .globl _boothowto,_bootdev 97 98 .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 99 .globl _cpu_high, _cpu_feature 100 101_cpu: .long 0 /* are we 386, 386sx, or 486 */ 102_cpu_id: .long 0 /* stepping ID */ 103_cpu_high: .long 0 /* highest arg to CPUID */ 104_cpu_feature: .long 0 /* features */ 105_cpu_vendor: .space 20 /* CPU origin code */ 106_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 107 108_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 109physfree: .long 0 /* phys addr of next free page */ 110 111#ifdef SMP 112 .globl _cpu0prvpage 113cpu0pp: .long 0 /* phys addr cpu0 private pg */ 114_cpu0prvpage: .long 0 /* relocated version */ 115 116 .globl _SMPpt 117SMPptpa: .long 0 /* phys addr SMP page table */ 118_SMPpt: .long 0 /* relocated version */ 119#endif /* SMP */ 120 121 .globl _IdlePTD 122_IdlePTD: .long 0 /* phys addr of kernel PTD */ 123 124#ifdef SMP 125 .globl _KPTphys 126#endif 127_KPTphys: .long 0 /* phys addr of kernel page tables */ 128 129 .globl _proc0paddr 130_proc0paddr: .long 0 /* address of proc 0 address space */ 131p0upa: .long 0 /* phys addr of proc0's UPAGES */ 132 133vm86phystk: .long 0 /* PA of vm86/bios stack */ 134 135 .globl _vm86paddr, _vm86pa 136_vm86paddr: .long 0 /* address of vm86 region */ 137_vm86pa: .long 0 /* phys addr of vm86 region */ 138 139#ifdef BDE_DEBUGGER 140 .globl _bdb_exists /* flag to indicate BDE debugger is present */ 141_bdb_exists: .long 0 142#endif 143 144#ifdef PC98 145 .globl _pc98_system_parameter 146_pc98_system_parameter: 147 .space 0x240 148#endif 149 150/********************************************************************** 151 * 152 * Some handy macros 153 * 154 */ 155 156#define R(foo) ((foo)-KERNBASE) 157 158#define ALLOCPAGES(foo) \ 159 movl R(physfree), %esi ; \ 160 movl $((foo)*PAGE_SIZE), %eax ; \ 161 addl %esi, %eax ; \ 162 movl %eax, R(physfree) ; \ 163 movl %esi, %edi ; \ 164 movl $((foo)*PAGE_SIZE),%ecx ; \ 165 xorl %eax,%eax ; \ 166 cld ; \ 167 rep ; \ 168 stosb 169 170/* 171 * fillkpt 172 * eax = page frame address 173 * ebx = index into page table 174 * ecx = how many pages to map 175 * base = base address of page dir/table 176 * prot = protection bits 177 */ 178#define fillkpt(base, prot) \ 179 shll $2,%ebx ; \ 180 addl base,%ebx ; \ 181 orl $PG_V,%eax ; \ 182 orl prot,%eax ; \ 1831: movl %eax,(%ebx) ; \ 184 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 185 addl $4,%ebx ; /* next pte */ \ 186 loop 1b 187 188/* 189 * fillkptphys(prot) 190 * eax = physical address 191 * ecx = how many pages to map 192 * prot = protection bits 193 */ 194#define fillkptphys(prot) \ 195 movl %eax, %ebx ; \ 196 shrl $PAGE_SHIFT, %ebx ; \ 197 fillkpt(R(_KPTphys), prot) 198 199 .text 200/********************************************************************** 201 * 202 * This is where the bootblocks start us, set the ball rolling... 203 * 204 */ 205NON_GPROF_ENTRY(btext) 206 207#ifdef PC98 208 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 209 movl $0xa1400,%esi 210 movl $R(_pc98_system_parameter),%edi 211 movl $0x0240,%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/* Tell the bios to warmboot next time */ 227 movw $0x1234,0x472 228#endif /* PC98 */ 229 230/* Set up a real frame in case the double return in newboot is executed. */ 231 pushl %ebp 232 movl %esp, %ebp 233 234/* Don't trust what the BIOS gives for eflags. */ 235 pushl $PSL_KERNEL 236 popfl 237 238/* 239 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 240 * to set %cs, %ds, %es and %ss. 241 */ 242 mov %ds, %ax 243 mov %ax, %fs 244 mov %ax, %gs 245 246 call recover_bootinfo 247 248/* Get onto a stack that we can trust. */ 249/* 250 * XXX this step is delayed in case recover_bootinfo needs to return via 251 * the old stack, but it need not be, since recover_bootinfo actually 252 * returns via the old frame. 253 */ 254 movl $R(HIDENAME(tmpstk)),%esp 255 256#ifdef PC98 257 /* pc98_machine_type & M_EPSON_PC98 */ 258 testb $0x02,R(_pc98_system_parameter)+220 259 jz 3f 260 /* epson_machine_id <= 0x0b */ 261 cmpb $0x0b,R(_pc98_system_parameter)+224 262 ja 3f 263 264 /* count up memory */ 265 movl $0x100000,%eax /* next, talley remaining memory */ 266 movl $0xFFF-0x100,%ecx 2671: movl 0(%eax),%ebx /* save location to check */ 268 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 269 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 270 jne 2f 271 movl %ebx,0(%eax) /* restore memory */ 272 addl $PAGE_SIZE,%eax 273 loop 1b 2742: subl $0x100000,%eax 275 shrl $17,%eax 276 movb %al,R(_pc98_system_parameter)+1 2773: 278 279 movw R(_pc98_system_parameter+0x86),%ax 280 movw %ax,R(_cpu_id) 281#endif 282 283 call identify_cpu 284 285/* clear bss */ 286/* 287 * XXX this should be done a little earlier. 288 * 289 * XXX we don't check that there is memory for our bss and page tables 290 * before using it. 291 * 292 * XXX the boot program somewhat bogusly clears the bss. We still have 293 * to do it in case we were unzipped by kzipboot. Then the boot program 294 * only clears kzipboot's bss. 295 * 296 * XXX the gdt and idt are still somewhere in the boot program. We 297 * depend on the convention that the boot program is below 1MB and we 298 * are above 1MB to keep the gdt and idt away from the bss and page 299 * tables. The idt is only used if BDE_DEBUGGER is enabled. 300 */ 301 movl $R(_end),%ecx 302 movl $R(_edata),%edi 303 subl %edi,%ecx 304 xorl %eax,%eax 305 cld 306 rep 307 stosb 308 309 call create_pagetables 310 311/* 312 * If the CPU has support for VME, turn it on. 313 */ 314 testl $CPUID_VME, R(_cpu_feature) 315 jz 1f 316 movl %cr4, %eax 317 orl $CR4_VME, %eax 318 movl %eax, %cr4 3191: 320 321#ifdef BDE_DEBUGGER 322/* 323 * Adjust as much as possible for paging before enabling paging so that the 324 * adjustments can be traced. 325 */ 326 call bdb_prepare_paging 327#endif 328 329/* Now enable paging */ 330 movl R(_IdlePTD), %eax 331 movl %eax,%cr3 /* load ptd addr into mmu */ 332 movl %cr0,%eax /* get control word */ 333 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 334 movl %eax,%cr0 /* and let's page NOW! */ 335 336#ifdef BDE_DEBUGGER 337/* 338 * Complete the adjustments for paging so that we can keep tracing through 339 * initi386() after the low (physical) addresses for the gdt and idt become 340 * invalid. 341 */ 342 call bdb_commit_paging 343#endif 344 345 pushl $begin /* jump to high virtualized address */ 346 ret 347 348/* now running relocated at KERNBASE where the system is linked to run */ 349begin: 350 /* set up bootstrap stack */ 351 movl _proc0paddr,%eax /* location of in-kernel pages */ 352 leal UPAGES*PAGE_SIZE(%eax),%esp /* bootstrap stack end location */ 353 354 xorl %ebp,%ebp /* mark end of frames */ 355 356 movl _IdlePTD,%esi 357 movl %esi,PCB_CR3(%eax) 358 359 pushl physfree /* value of first for init386(first) */ 360 call _init386 /* wire 386 chip for unix operation */ 361 362 /* 363 * Clean up the stack in a way that db_numargs() understands, so 364 * that backtraces in ddb don't underrun the stack. Traps for 365 * inaccessible memory are more fatal than usual this early. 366 */ 367 addl $4,%esp 368 369 call _mi_startup /* autoconfiguration, mountroot etc */ 370 /* NOTREACHED */ 371 addl $0,%esp /* for db_numargs() again */ 372 373/* 374 * Signal trampoline, copied to top of user stack 375 */ 376NON_GPROF_ENTRY(sigcode) 377 call *SIGF_HANDLER(%esp) /* call signal handler */ 378 lea SIGF_UC(%esp),%eax /* get ucontext_t */ 379 pushl %eax 380 testl $PSL_VM,UC_EFLAGS(%eax) 381 jne 9f 382 movl UC_GS(%eax),%gs /* restore %gs */ 3839: 384 movl $SYS_sigreturn,%eax 385 pushl %eax /* junk to fake return addr. */ 386 int $0x80 /* enter kernel with args */ 3870: jmp 0b 388 389 ALIGN_TEXT 390_osigcode: 391 call *SIGF_HANDLER(%esp) /* call signal handler */ 392 lea SIGF_SC(%esp),%eax /* get sigcontext */ 393 pushl %eax 394 testl $PSL_VM,SC_PS(%eax) 395 jne 9f 396 movl SC_GS(%eax),%gs /* restore %gs */ 3979: 398 movl $0x01d516,SC_TRAPNO(%eax) /* magic: 0ldSiG */ 399 movl $SYS_sigreturn,%eax 400 pushl %eax /* junk to fake return addr. */ 401 int $0x80 /* enter kernel with args */ 4020: jmp 0b 403 404 ALIGN_TEXT 405_esigcode: 406 407 .data 408 .globl _szsigcode, _szosigcode 409_szsigcode: 410 .long _esigcode-_sigcode 411_szosigcode: 412 .long _esigcode-_osigcode 413 .text 414 415/********************************************************************** 416 * 417 * Recover the bootinfo passed to us from the boot program 418 * 419 */ 420recover_bootinfo: 421 /* 422 * This code is called in different ways depending on what loaded 423 * and started the kernel. This is used to detect how we get the 424 * arguments from the other code and what we do with them. 425 * 426 * Old disk boot blocks: 427 * (*btext)(howto, bootdev, cyloffset, esym); 428 * [return address == 0, and can NOT be returned to] 429 * [cyloffset was not supported by the FreeBSD boot code 430 * and always passed in as 0] 431 * [esym is also known as total in the boot code, and 432 * was never properly supported by the FreeBSD boot code] 433 * 434 * Old diskless netboot code: 435 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 436 * [return address != 0, and can NOT be returned to] 437 * If we are being booted by this code it will NOT work, 438 * so we are just going to halt if we find this case. 439 * 440 * New uniform boot code: 441 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 442 * [return address != 0, and can be returned to] 443 * 444 * There may seem to be a lot of wasted arguments in here, but 445 * that is so the newer boot code can still load very old kernels 446 * and old boot code can load new kernels. 447 */ 448 449 /* 450 * The old style disk boot blocks fake a frame on the stack and 451 * did an lret to get here. The frame on the stack has a return 452 * address of 0. 453 */ 454 cmpl $0,4(%ebp) 455 je olddiskboot 456 457 /* 458 * We have some form of return address, so this is either the 459 * old diskless netboot code, or the new uniform code. That can 460 * be detected by looking at the 5th argument, if it is 0 461 * we are being booted by the new uniform boot code. 462 */ 463 cmpl $0,24(%ebp) 464 je newboot 465 466 /* 467 * Seems we have been loaded by the old diskless boot code, we 468 * don't stand a chance of running as the diskless structure 469 * changed considerably between the two, so just halt. 470 */ 471 hlt 472 473 /* 474 * We have been loaded by the new uniform boot code. 475 * Let's check the bootinfo version, and if we do not understand 476 * it we return to the loader with a status of 1 to indicate this error 477 */ 478newboot: 479 movl 28(%ebp),%ebx /* &bootinfo.version */ 480 movl BI_VERSION(%ebx),%eax 481 cmpl $1,%eax /* We only understand version 1 */ 482 je 1f 483 movl $1,%eax /* Return status */ 484 leave 485 /* 486 * XXX this returns to our caller's caller (as is required) since 487 * we didn't set up a frame and our caller did. 488 */ 489 ret 490 4911: 492 /* 493 * If we have a kernelname copy it in 494 */ 495 movl BI_KERNELNAME(%ebx),%esi 496 cmpl $0,%esi 497 je 2f /* No kernelname */ 498 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 499 movl $R(_kernelname),%edi 500 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 501 je 1f 502 movb $'/',(%edi) 503 incl %edi 504 decl %ecx 5051: 506 cld 507 rep 508 movsb 509 5102: 511 /* 512 * Determine the size of the boot loader's copy of the bootinfo 513 * struct. This is impossible to do properly because old versions 514 * of the struct don't contain a size field and there are 2 old 515 * versions with the same version number. 516 */ 517 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 518 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 519 je got_bi_size /* no, sizeless version */ 520 movl BI_SIZE(%ebx),%ecx 521got_bi_size: 522 523 /* 524 * Copy the common part of the bootinfo struct 525 */ 526 movl %ebx,%esi 527 movl $R(_bootinfo),%edi 528 cmpl $BOOTINFO_SIZE,%ecx 529 jbe got_common_bi_size 530 movl $BOOTINFO_SIZE,%ecx 531got_common_bi_size: 532 cld 533 rep 534 movsb 535 536#ifdef NFS_ROOT 537#ifndef BOOTP_NFSV3 538 /* 539 * If we have a nfs_diskless structure copy it in 540 */ 541 movl BI_NFS_DISKLESS(%ebx),%esi 542 cmpl $0,%esi 543 je olddiskboot 544 movl $R(_nfs_diskless),%edi 545 movl $NFSDISKLESS_SIZE,%ecx 546 cld 547 rep 548 movsb 549 movl $R(_nfs_diskless_valid),%edi 550 movl $1,(%edi) 551#endif 552#endif 553 554 /* 555 * The old style disk boot. 556 * (*btext)(howto, bootdev, cyloffset, esym); 557 * Note that the newer boot code just falls into here to pick 558 * up howto and bootdev, cyloffset and esym are no longer used 559 */ 560olddiskboot: 561 movl 8(%ebp),%eax 562 movl %eax,R(_boothowto) 563 movl 12(%ebp),%eax 564 movl %eax,R(_bootdev) 565 566 ret 567 568 569/********************************************************************** 570 * 571 * Identify the CPU and initialize anything special about it 572 * 573 */ 574identify_cpu: 575 576 /* Try to toggle alignment check flag; does not exist on 386. */ 577 pushfl 578 popl %eax 579 movl %eax,%ecx 580 orl $PSL_AC,%eax 581 pushl %eax 582 popfl 583 pushfl 584 popl %eax 585 xorl %ecx,%eax 586 andl $PSL_AC,%eax 587 pushl %ecx 588 popfl 589 590 testl %eax,%eax 591 jnz try486 592 593 /* NexGen CPU does not have aligment check flag. */ 594 pushfl 595 movl $0x5555, %eax 596 xorl %edx, %edx 597 movl $2, %ecx 598 clc 599 divl %ecx 600 jz trynexgen 601 popfl 602 movl $CPU_386,R(_cpu) 603 jmp 3f 604 605trynexgen: 606 popfl 607 movl $CPU_NX586,R(_cpu) 608 movl $0x4778654e,R(_cpu_vendor) # store vendor string 609 movl $0x72446e65,R(_cpu_vendor+4) 610 movl $0x6e657669,R(_cpu_vendor+8) 611 movl $0,R(_cpu_vendor+12) 612 jmp 3f 613 614try486: /* Try to toggle identification flag; does not exist on early 486s. */ 615 pushfl 616 popl %eax 617 movl %eax,%ecx 618 xorl $PSL_ID,%eax 619 pushl %eax 620 popfl 621 pushfl 622 popl %eax 623 xorl %ecx,%eax 624 andl $PSL_ID,%eax 625 pushl %ecx 626 popfl 627 628 testl %eax,%eax 629 jnz trycpuid 630 movl $CPU_486,R(_cpu) 631 632 /* 633 * Check Cyrix CPU 634 * Cyrix CPUs do not change the undefined flags following 635 * execution of the divide instruction which divides 5 by 2. 636 * 637 * Note: CPUID is enabled on M2, so it passes another way. 638 */ 639 pushfl 640 movl $0x5555, %eax 641 xorl %edx, %edx 642 movl $2, %ecx 643 clc 644 divl %ecx 645 jnc trycyrix 646 popfl 647 jmp 3f /* You may use Intel CPU. */ 648 649trycyrix: 650 popfl 651 /* 652 * IBM Bluelighting CPU also doesn't change the undefined flags. 653 * Because IBM doesn't disclose the information for Bluelighting 654 * CPU, we couldn't distinguish it from Cyrix's (including IBM 655 * brand of Cyrix CPUs). 656 */ 657 movl $0x69727943,R(_cpu_vendor) # store vendor string 658 movl $0x736e4978,R(_cpu_vendor+4) 659 movl $0x64616574,R(_cpu_vendor+8) 660 jmp 3f 661 662trycpuid: /* Use the `cpuid' instruction. */ 663 xorl %eax,%eax 664 cpuid # cpuid 0 665 movl %eax,R(_cpu_high) # highest capability 666 movl %ebx,R(_cpu_vendor) # store vendor string 667 movl %edx,R(_cpu_vendor+4) 668 movl %ecx,R(_cpu_vendor+8) 669 movb $0,R(_cpu_vendor+12) 670 671 movl $1,%eax 672 cpuid # cpuid 1 673 movl %eax,R(_cpu_id) # store cpu_id 674 movl %edx,R(_cpu_feature) # store cpu_feature 675 rorl $8,%eax # extract family type 676 andl $15,%eax 677 cmpl $5,%eax 678 jae 1f 679 680 /* less than Pentium; must be 486 */ 681 movl $CPU_486,R(_cpu) 682 jmp 3f 6831: 684 /* a Pentium? */ 685 cmpl $5,%eax 686 jne 2f 687 movl $CPU_586,R(_cpu) 688 jmp 3f 6892: 690 /* Greater than Pentium...call it a Pentium Pro */ 691 movl $CPU_686,R(_cpu) 6923: 693 ret 694 695 696/********************************************************************** 697 * 698 * Create the first page directory and its page tables. 699 * 700 */ 701 702create_pagetables: 703 704 testl $CPUID_PGE, R(_cpu_feature) 705 jz 1f 706 movl %cr4, %eax 707 orl $CR4_PGE, %eax 708 movl %eax, %cr4 7091: 710 711/* Find end of kernel image (rounded up to a page boundary). */ 712 movl $R(_end),%esi 713 714/* Include symbols, if any. */ 715 movl R(_bootinfo+BI_ESYMTAB),%edi 716 testl %edi,%edi 717 je over_symalloc 718 movl %edi,%esi 719 movl $KERNBASE,%edi 720 addl %edi,R(_bootinfo+BI_SYMTAB) 721 addl %edi,R(_bootinfo+BI_ESYMTAB) 722over_symalloc: 723 724/* If we are told where the end of the kernel space is, believe it. */ 725 movl R(_bootinfo+BI_KERNEND),%edi 726 testl %edi,%edi 727 je no_kernend 728 movl %edi,%esi 729no_kernend: 730 731 addl $PAGE_MASK,%esi 732 andl $~PAGE_MASK,%esi 733 movl %esi,R(_KERNend) /* save end of kernel */ 734 movl %esi,R(physfree) /* next free page is at end of kernel */ 735 736/* Allocate Kernel Page Tables */ 737 ALLOCPAGES(NKPT) 738 movl %esi,R(_KPTphys) 739 740/* Allocate Page Table Directory */ 741 ALLOCPAGES(1) 742 movl %esi,R(_IdlePTD) 743 744/* Allocate UPAGES */ 745 ALLOCPAGES(UPAGES) 746 movl %esi,R(p0upa) 747 addl $KERNBASE, %esi 748 movl %esi, R(_proc0paddr) 749 750 ALLOCPAGES(1) /* vm86/bios stack */ 751 movl %esi,R(vm86phystk) 752 753 ALLOCPAGES(3) /* pgtable + ext + IOPAGES */ 754 movl %esi,R(_vm86pa) 755 addl $KERNBASE, %esi 756 movl %esi, R(_vm86paddr) 757 758#ifdef SMP 759/* Allocate cpu0's private data page */ 760 ALLOCPAGES(1) 761 movl %esi,R(cpu0pp) 762 addl $KERNBASE, %esi 763 movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 764 765/* Allocate SMP page table page */ 766 ALLOCPAGES(1) 767 movl %esi,R(SMPptpa) 768 addl $KERNBASE, %esi 769 movl %esi, R(_SMPpt) /* relocated to KVM space */ 770#endif /* SMP */ 771 772/* Map read-only from zero to the end of the kernel text section */ 773 xorl %eax, %eax 774#ifdef BDE_DEBUGGER 775/* If the debugger is present, actually map everything read-write. */ 776 cmpl $0,R(_bdb_exists) 777 jne map_read_write 778#endif 779 xorl %edx,%edx 780 781#if !defined(SMP) 782 testl $CPUID_PGE, R(_cpu_feature) 783 jz 2f 784 orl $PG_G,%edx 785#endif 786 7872: movl $R(_etext),%ecx 788 addl $PAGE_MASK,%ecx 789 shrl $PAGE_SHIFT,%ecx 790 fillkptphys(%edx) 791 792/* Map read-write, data, bss and symbols */ 793 movl $R(_etext),%eax 794 addl $PAGE_MASK, %eax 795 andl $~PAGE_MASK, %eax 796map_read_write: 797 movl $PG_RW,%edx 798#if !defined(SMP) 799 testl $CPUID_PGE, R(_cpu_feature) 800 jz 1f 801 orl $PG_G,%edx 802#endif 803 8041: movl R(_KERNend),%ecx 805 subl %eax,%ecx 806 shrl $PAGE_SHIFT,%ecx 807 fillkptphys(%edx) 808 809/* Map page directory. */ 810 movl R(_IdlePTD), %eax 811 movl $1, %ecx 812 fillkptphys($PG_RW) 813 814/* Map proc0's UPAGES in the physical way ... */ 815 movl R(p0upa), %eax 816 movl $UPAGES, %ecx 817 fillkptphys($PG_RW) 818 819/* Map ISA hole */ 820 movl $ISA_HOLE_START, %eax 821 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 822 fillkptphys($PG_RW) 823 824/* Map space for the vm86 region */ 825 movl R(vm86phystk), %eax 826 movl $4, %ecx 827 fillkptphys($PG_RW) 828 829/* Map page 0 into the vm86 page table */ 830 movl $0, %eax 831 movl $0, %ebx 832 movl $1, %ecx 833 fillkpt(R(_vm86pa), $PG_RW|PG_U) 834 835/* ...likewise for the ISA hole */ 836 movl $ISA_HOLE_START, %eax 837 movl $ISA_HOLE_START>>PAGE_SHIFT, %ebx 838 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 839 fillkpt(R(_vm86pa), $PG_RW|PG_U) 840 841#ifdef SMP 842/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 843 movl R(cpu0pp), %eax 844 movl $1, %ecx 845 fillkptphys($PG_RW) 846 847/* Map SMP page table page into global kmem FWIW */ 848 movl R(SMPptpa), %eax 849 movl $1, %ecx 850 fillkptphys($PG_RW) 851 852/* Map the private page into the SMP page table */ 853 movl R(cpu0pp), %eax 854 movl $0, %ebx /* pte offset = 0 */ 855 movl $1, %ecx /* one private page coming right up */ 856 fillkpt(R(SMPptpa), $PG_RW) 857 858/* ... and put the page table table in the pde. */ 859 movl R(SMPptpa), %eax 860 movl $MPPTDI, %ebx 861 movl $1, %ecx 862 fillkpt(R(_IdlePTD), $PG_RW) 863 864/* Fakeup VA for the local apic to allow early traps. */ 865 ALLOCPAGES(1) 866 movl %esi, %eax 867 movl $(NPTEPG-1), %ebx /* pte offset = NTEPG-1 */ 868 movl $1, %ecx /* one private pt coming right up */ 869 fillkpt(R(SMPptpa), $PG_RW) 870#endif /* SMP */ 871 872/* install a pde for temporary double map of bottom of VA */ 873 movl R(_KPTphys), %eax 874 xorl %ebx, %ebx 875 movl $1, %ecx 876 fillkpt(R(_IdlePTD), $PG_RW) 877 878/* install pde's for pt's */ 879 movl R(_KPTphys), %eax 880 movl $KPTDI, %ebx 881 movl $NKPT, %ecx 882 fillkpt(R(_IdlePTD), $PG_RW) 883 884/* install a pde recursively mapping page directory as a page table */ 885 movl R(_IdlePTD), %eax 886 movl $PTDPTDI, %ebx 887 movl $1,%ecx 888 fillkpt(R(_IdlePTD), $PG_RW) 889 890 ret 891 892#ifdef BDE_DEBUGGER 893bdb_prepare_paging: 894 cmpl $0,R(_bdb_exists) 895 je bdb_prepare_paging_exit 896 897 subl $6,%esp 898 899 /* 900 * Copy and convert debugger entries from the bootstrap gdt and idt 901 * to the kernel gdt and idt. Everything is still in low memory. 902 * Tracing continues to work after paging is enabled because the 903 * low memory addresses remain valid until everything is relocated. 904 * However, tracing through the setidt() that initializes the trace 905 * trap will crash. 906 */ 907 sgdt (%esp) 908 movl 2(%esp),%esi /* base address of bootstrap gdt */ 909 movl $R(_gdt),%edi 910 movl %edi,2(%esp) /* prepare to load kernel gdt */ 911 movl $8*18/4,%ecx 912 cld 913 rep /* copy gdt */ 914 movsl 915 movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 916 movb $0x92,-8+5(%edi) 917 lgdt (%esp) 918 919 sidt (%esp) 920 movl 2(%esp),%esi /* base address of current idt */ 921 movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 922 movw 8(%esi),%ax 923 movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 924 movl 8+2(%esi),%eax 925 movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 926 movl 24+4(%esi),%eax /* same for bpt descriptor */ 927 movw 24(%esi),%ax 928 movl %eax,R(bdb_bpt_ljmp+1) 929 movl 24+2(%esi),%eax 930 movw %ax,R(bdb_bpt_ljmp+5) 931 movl R(_idt),%edi 932 movl %edi,2(%esp) /* prepare to load kernel idt */ 933 movl $8*4/4,%ecx 934 cld 935 rep /* copy idt */ 936 movsl 937 lidt (%esp) 938 939 addl $6,%esp 940 941bdb_prepare_paging_exit: 942 ret 943 944/* Relocate debugger gdt entries and gdt and idt pointers. */ 945bdb_commit_paging: 946 cmpl $0,_bdb_exists 947 je bdb_commit_paging_exit 948 949 movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 950 movl $9,%ecx 951reloc_gdt: 952 movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 953 addl $8,%eax /* now KERNBASE>>24 */ 954 loop reloc_gdt 955 956 subl $6,%esp 957 sgdt (%esp) 958 addl $KERNBASE,2(%esp) 959 lgdt (%esp) 960 sidt (%esp) 961 addl $KERNBASE,2(%esp) 962 lidt (%esp) 963 addl $6,%esp 964 965 int $3 966 967bdb_commit_paging_exit: 968 ret 969 970#endif /* BDE_DEBUGGER */ 971