locore.s revision 164607
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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)locore.s 7.3 (Berkeley) 5/13/91 33 * $FreeBSD: head/sys/i386/i386/locore.s 164607 2006-11-25 23:00:46Z ru $ 34 * 35 * originally from: locore.s, by William F. Jolitz 36 * 37 * Substantially rewritten by David Greenman, Rod Grimes, 38 * Bruce Evans, Wolfgang Solfrank, Poul-Henning Kamp 39 * and many others. 40 */ 41 42#include "opt_bootp.h" 43#include "opt_compat.h" 44#include "opt_nfsroot.h" 45#include "opt_pmap.h" 46 47#include <sys/syscall.h> 48#include <sys/reboot.h> 49 50#include <machine/asmacros.h> 51#include <machine/cputypes.h> 52#include <machine/psl.h> 53#include <machine/pmap.h> 54#include <machine/specialreg.h> 55 56#include "assym.s" 57 58/* 59 * XXX 60 * 61 * Note: This version greatly munged to avoid various assembler errors 62 * that may be fixed in newer versions of gas. Perhaps newer versions 63 * will have more pleasant appearance. 64 */ 65 66/* 67 * PTmap is recursive pagemap at top of virtual address space. 68 * Within PTmap, the page directory can be found (third indirection). 69 */ 70 .globl PTmap,PTD,PTDpde 71 .set PTmap,(PTDPTDI << PDRSHIFT) 72 .set PTD,PTmap + (PTDPTDI * PAGE_SIZE) 73 .set PTDpde,PTD + (PTDPTDI * PDESIZE) 74 75#ifdef SMP 76/* 77 * Define layout of per-cpu address space. 78 * This is "constructed" in locore.s on the BSP and in mp_machdep.c 79 * for each AP. DO NOT REORDER THESE WITHOUT UPDATING THE REST! 80 */ 81 .globl SMP_prvspace 82 .set SMP_prvspace,(MPPTDI << PDRSHIFT) 83#endif /* SMP */ 84 85/* 86 * Compiled KERNBASE location and the kernel load address 87 */ 88 .globl kernbase 89 .set kernbase,KERNBASE 90 .globl kernload 91 .set kernload,KERNLOAD 92 93/* 94 * Globals 95 */ 96 .data 97 ALIGN_DATA /* just to be sure */ 98 99 .space 0x2000 /* space for tmpstk - temporary stack */ 100tmpstk: 101 102 .globl bootinfo 103bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 104 105 .globl KERNend 106KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 107physfree: .long 0 /* phys addr of next free page */ 108 109#ifdef SMP 110 .globl cpu0prvpage 111cpu0pp: .long 0 /* phys addr cpu0 private pg */ 112cpu0prvpage: .long 0 /* relocated version */ 113 114 .globl SMPpt 115SMPptpa: .long 0 /* phys addr SMP page table */ 116SMPpt: .long 0 /* relocated version */ 117#endif /* SMP */ 118 119 .globl IdlePTD 120IdlePTD: .long 0 /* phys addr of kernel PTD */ 121 122#ifdef PAE 123 .globl IdlePDPT 124IdlePDPT: .long 0 /* phys addr of kernel PDPT */ 125#endif 126 127#ifdef SMP 128 .globl KPTphys 129#endif 130KPTphys: .long 0 /* phys addr of kernel page tables */ 131 132 .globl proc0kstack 133proc0uarea: .long 0 /* address of proc 0 uarea (unused)*/ 134proc0kstack: .long 0 /* address of proc 0 kstack space */ 135p0upa: .long 0 /* phys addr of proc0 UAREA (unused) */ 136p0kpa: .long 0 /* phys addr of proc0's STACK */ 137 138vm86phystk: .long 0 /* PA of vm86/bios stack */ 139 140 .globl vm86paddr, vm86pa 141vm86paddr: .long 0 /* address of vm86 region */ 142vm86pa: .long 0 /* phys addr of vm86 region */ 143 144#ifdef PC98 145 .globl pc98_system_parameter 146pc98_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 $PTESHIFT,%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 $PTESIZE,%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/* Tell the bios to warmboot next time */ 217 movw $0x1234,0x472 218#endif /* PC98 */ 219 220/* Set up a real frame in case the double return in newboot is executed. */ 221 pushl %ebp 222 movl %esp, %ebp 223 224/* Don't trust what the BIOS gives for eflags. */ 225 pushl $PSL_KERNEL 226 popfl 227 228/* 229 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 230 * to set %cs, %ds, %es and %ss. 231 */ 232 mov %ds, %ax 233 mov %ax, %fs 234 mov %ax, %gs 235 236/* 237 * Clear the bss. Not all boot programs do it, and it is our job anyway. 238 * 239 * XXX we don't check that there is memory for our bss and page tables 240 * before using it. 241 * 242 * Note: we must be careful to not overwrite an active gdt or idt. They 243 * inactive from now until we switch to new ones, since we don't load any 244 * more segment registers or permit interrupts until after the switch. 245 */ 246 movl $R(end),%ecx 247 movl $R(edata),%edi 248 subl %edi,%ecx 249 xorl %eax,%eax 250 cld 251 rep 252 stosb 253 254 call recover_bootinfo 255 256/* Get onto a stack that we can trust. */ 257/* 258 * XXX this step is delayed in case recover_bootinfo needs to return via 259 * the old stack, but it need not be, since recover_bootinfo actually 260 * returns via the old frame. 261 */ 262 movl $R(tmpstk),%esp 263 264#ifdef PC98 265 /* pc98_machine_type & M_EPSON_PC98 */ 266 testb $0x02,R(pc98_system_parameter)+220 267 jz 3f 268 /* epson_machine_id <= 0x0b */ 269 cmpb $0x0b,R(pc98_system_parameter)+224 270 ja 3f 271 272 /* count up memory */ 273 movl $0x100000,%eax /* next, talley remaining memory */ 274 movl $0xFFF-0x100,%ecx 2751: movl 0(%eax),%ebx /* save location to check */ 276 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 277 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 278 jne 2f 279 movl %ebx,0(%eax) /* restore memory */ 280 addl $PAGE_SIZE,%eax 281 loop 1b 2822: subl $0x100000,%eax 283 shrl $17,%eax 284 movb %al,R(pc98_system_parameter)+1 2853: 286 287 movw R(pc98_system_parameter+0x86),%ax 288 movw %ax,R(cpu_id) 289#endif 290 291 call identify_cpu 292 call create_pagetables 293 294/* 295 * If the CPU has support for VME, turn it on. 296 */ 297 testl $CPUID_VME, R(cpu_feature) 298 jz 1f 299 movl %cr4, %eax 300 orl $CR4_VME, %eax 301 movl %eax, %cr4 3021: 303 304/* Now enable paging */ 305#ifdef PAE 306 movl R(IdlePDPT), %eax 307 movl %eax, %cr3 308 movl %cr4, %eax 309 orl $CR4_PAE, %eax 310 movl %eax, %cr4 311#else 312 movl R(IdlePTD), %eax 313 movl %eax,%cr3 /* load ptd addr into mmu */ 314#endif 315 movl %cr0,%eax /* get control word */ 316 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 317 movl %eax,%cr0 /* and let's page NOW! */ 318 319 pushl $begin /* jump to high virtualized address */ 320 ret 321 322/* now running relocated at KERNBASE where the system is linked to run */ 323begin: 324 /* set up bootstrap stack */ 325 movl proc0kstack,%eax /* location of in-kernel stack */ 326 /* bootstrap stack end location */ 327 leal (KSTACK_PAGES*PAGE_SIZE-PCB_SIZE)(%eax),%esp 328 329 xorl %ebp,%ebp /* mark end of frames */ 330 331#ifdef PAE 332 movl IdlePDPT,%esi 333#else 334 movl IdlePTD,%esi 335#endif 336 movl %esi,(KSTACK_PAGES*PAGE_SIZE-PCB_SIZE+PCB_CR3)(%eax) 337 338 pushl physfree /* value of first for init386(first) */ 339 call init386 /* wire 386 chip for unix operation */ 340 341 /* 342 * Clean up the stack in a way that db_numargs() understands, so 343 * that backtraces in ddb don't underrun the stack. Traps for 344 * inaccessible memory are more fatal than usual this early. 345 */ 346 addl $4,%esp 347 348 call mi_startup /* autoconfiguration, mountroot etc */ 349 /* NOTREACHED */ 350 addl $0,%esp /* for db_numargs() again */ 351 352/* 353 * Signal trampoline, copied to top of user stack 354 */ 355NON_GPROF_ENTRY(sigcode) 356 calll *SIGF_HANDLER(%esp) 357 leal SIGF_UC(%esp),%eax /* get ucontext */ 358 pushl %eax 359 testl $PSL_VM,UC_EFLAGS(%eax) 360 jne 1f 361 movl UC_GS(%eax),%gs /* restore %gs */ 3621: 363 movl $SYS_sigreturn,%eax 364 pushl %eax /* junk to fake return addr. */ 365 int $0x80 /* enter kernel with args */ 366 /* on stack */ 3671: 368 jmp 1b 369 370#ifdef COMPAT_FREEBSD4 371 ALIGN_TEXT 372freebsd4_sigcode: 373 calll *SIGF_HANDLER(%esp) 374 leal SIGF_UC4(%esp),%eax /* get ucontext */ 375 pushl %eax 376 testl $PSL_VM,UC4_EFLAGS(%eax) 377 jne 1f 378 movl UC4_GS(%eax),%gs /* restore %gs */ 3791: 380 movl $344,%eax /* 4.x SYS_sigreturn */ 381 pushl %eax /* junk to fake return addr. */ 382 int $0x80 /* enter kernel with args */ 383 /* on stack */ 3841: 385 jmp 1b 386#endif 387 388#ifdef COMPAT_43 389 ALIGN_TEXT 390osigcode: 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 $103,%eax /* 3.x SYS_sigreturn */ 399 pushl %eax /* junk to fake return addr. */ 400 int $0x80 /* enter kernel with args */ 4010: jmp 0b 402#endif /* COMPAT_43 */ 403 404 ALIGN_TEXT 405esigcode: 406 407 .data 408 .globl szsigcode 409szsigcode: 410 .long esigcode-sigcode 411#ifdef COMPAT_FREEBSD4 412 .globl szfreebsd4_sigcode 413szfreebsd4_sigcode: 414 .long esigcode-freebsd4_sigcode 415#endif 416#ifdef COMPAT_43 417 .globl szosigcode 418szosigcode: 419 .long esigcode-osigcode 420#endif 421 .text 422 423/********************************************************************** 424 * 425 * Recover the bootinfo passed to us from the boot program 426 * 427 */ 428recover_bootinfo: 429 /* 430 * This code is called in different ways depending on what loaded 431 * and started the kernel. This is used to detect how we get the 432 * arguments from the other code and what we do with them. 433 * 434 * Old disk boot blocks: 435 * (*btext)(howto, bootdev, cyloffset, esym); 436 * [return address == 0, and can NOT be returned to] 437 * [cyloffset was not supported by the FreeBSD boot code 438 * and always passed in as 0] 439 * [esym is also known as total in the boot code, and 440 * was never properly supported by the FreeBSD boot code] 441 * 442 * Old diskless netboot code: 443 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 444 * [return address != 0, and can NOT be returned to] 445 * If we are being booted by this code it will NOT work, 446 * so we are just going to halt if we find this case. 447 * 448 * New uniform boot code: 449 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 450 * [return address != 0, and can be returned to] 451 * 452 * There may seem to be a lot of wasted arguments in here, but 453 * that is so the newer boot code can still load very old kernels 454 * and old boot code can load new kernels. 455 */ 456 457 /* 458 * The old style disk boot blocks fake a frame on the stack and 459 * did an lret to get here. The frame on the stack has a return 460 * address of 0. 461 */ 462 cmpl $0,4(%ebp) 463 je olddiskboot 464 465 /* 466 * We have some form of return address, so this is either the 467 * old diskless netboot code, or the new uniform code. That can 468 * be detected by looking at the 5th argument, if it is 0 469 * we are being booted by the new uniform boot code. 470 */ 471 cmpl $0,24(%ebp) 472 je newboot 473 474 /* 475 * Seems we have been loaded by the old diskless boot code, we 476 * don't stand a chance of running as the diskless structure 477 * changed considerably between the two, so just halt. 478 */ 479 hlt 480 481 /* 482 * We have been loaded by the new uniform boot code. 483 * Let's check the bootinfo version, and if we do not understand 484 * it we return to the loader with a status of 1 to indicate this error 485 */ 486newboot: 487 movl 28(%ebp),%ebx /* &bootinfo.version */ 488 movl BI_VERSION(%ebx),%eax 489 cmpl $1,%eax /* We only understand version 1 */ 490 je 1f 491 movl $1,%eax /* Return status */ 492 leave 493 /* 494 * XXX this returns to our caller's caller (as is required) since 495 * we didn't set up a frame and our caller did. 496 */ 497 ret 498 4991: 500 /* 501 * If we have a kernelname copy it in 502 */ 503 movl BI_KERNELNAME(%ebx),%esi 504 cmpl $0,%esi 505 je 2f /* No kernelname */ 506 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 507 movl $R(kernelname),%edi 508 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 509 je 1f 510 movb $'/',(%edi) 511 incl %edi 512 decl %ecx 5131: 514 cld 515 rep 516 movsb 517 5182: 519 /* 520 * Determine the size of the boot loader's copy of the bootinfo 521 * struct. This is impossible to do properly because old versions 522 * of the struct don't contain a size field and there are 2 old 523 * versions with the same version number. 524 */ 525 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 526 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 527 je got_bi_size /* no, sizeless version */ 528 movl BI_SIZE(%ebx),%ecx 529got_bi_size: 530 531 /* 532 * Copy the common part of the bootinfo struct 533 */ 534 movl %ebx,%esi 535 movl $R(bootinfo),%edi 536 cmpl $BOOTINFO_SIZE,%ecx 537 jbe got_common_bi_size 538 movl $BOOTINFO_SIZE,%ecx 539got_common_bi_size: 540 cld 541 rep 542 movsb 543 544#ifdef NFS_ROOT 545#ifndef BOOTP_NFSV3 546 /* 547 * If we have a nfs_diskless structure copy it in 548 */ 549 movl BI_NFS_DISKLESS(%ebx),%esi 550 cmpl $0,%esi 551 je olddiskboot 552 movl $R(nfs_diskless),%edi 553 movl $NFSDISKLESS_SIZE,%ecx 554 cld 555 rep 556 movsb 557 movl $R(nfs_diskless_valid),%edi 558 movl $1,(%edi) 559#endif 560#endif 561 562 /* 563 * The old style disk boot. 564 * (*btext)(howto, bootdev, cyloffset, esym); 565 * Note that the newer boot code just falls into here to pick 566 * up howto and bootdev, cyloffset and esym are no longer used 567 */ 568olddiskboot: 569 movl 8(%ebp),%eax 570 movl %eax,R(boothowto) 571 movl 12(%ebp),%eax 572 movl %eax,R(bootdev) 573 574 ret 575 576 577/********************************************************************** 578 * 579 * Identify the CPU and initialize anything special about it 580 * 581 */ 582identify_cpu: 583 584 /* Try to toggle alignment check flag; does not exist on 386. */ 585 pushfl 586 popl %eax 587 movl %eax,%ecx 588 orl $PSL_AC,%eax 589 pushl %eax 590 popfl 591 pushfl 592 popl %eax 593 xorl %ecx,%eax 594 andl $PSL_AC,%eax 595 pushl %ecx 596 popfl 597 598 testl %eax,%eax 599 jnz try486 600 601 /* NexGen CPU does not have aligment check flag. */ 602 pushfl 603 movl $0x5555, %eax 604 xorl %edx, %edx 605 movl $2, %ecx 606 clc 607 divl %ecx 608 jz trynexgen 609 popfl 610 movl $CPU_386,R(cpu) 611 jmp 3f 612 613trynexgen: 614 popfl 615 movl $CPU_NX586,R(cpu) 616 movl $0x4778654e,R(cpu_vendor) # store vendor string 617 movl $0x72446e65,R(cpu_vendor+4) 618 movl $0x6e657669,R(cpu_vendor+8) 619 movl $0,R(cpu_vendor+12) 620 jmp 3f 621 622try486: /* Try to toggle identification flag; does not exist on early 486s. */ 623 pushfl 624 popl %eax 625 movl %eax,%ecx 626 xorl $PSL_ID,%eax 627 pushl %eax 628 popfl 629 pushfl 630 popl %eax 631 xorl %ecx,%eax 632 andl $PSL_ID,%eax 633 pushl %ecx 634 popfl 635 636 testl %eax,%eax 637 jnz trycpuid 638 movl $CPU_486,R(cpu) 639 640 /* 641 * Check Cyrix CPU 642 * Cyrix CPUs do not change the undefined flags following 643 * execution of the divide instruction which divides 5 by 2. 644 * 645 * Note: CPUID is enabled on M2, so it passes another way. 646 */ 647 pushfl 648 movl $0x5555, %eax 649 xorl %edx, %edx 650 movl $2, %ecx 651 clc 652 divl %ecx 653 jnc trycyrix 654 popfl 655 jmp 3f /* You may use Intel CPU. */ 656 657trycyrix: 658 popfl 659 /* 660 * IBM Bluelighting CPU also doesn't change the undefined flags. 661 * Because IBM doesn't disclose the information for Bluelighting 662 * CPU, we couldn't distinguish it from Cyrix's (including IBM 663 * brand of Cyrix CPUs). 664 */ 665 movl $0x69727943,R(cpu_vendor) # store vendor string 666 movl $0x736e4978,R(cpu_vendor+4) 667 movl $0x64616574,R(cpu_vendor+8) 668 jmp 3f 669 670trycpuid: /* Use the `cpuid' instruction. */ 671 xorl %eax,%eax 672 cpuid # cpuid 0 673 movl %eax,R(cpu_high) # highest capability 674 movl %ebx,R(cpu_vendor) # store vendor string 675 movl %edx,R(cpu_vendor+4) 676 movl %ecx,R(cpu_vendor+8) 677 movb $0,R(cpu_vendor+12) 678 679 movl $1,%eax 680 cpuid # cpuid 1 681 movl %eax,R(cpu_id) # store cpu_id 682 movl %ebx,R(cpu_procinfo) # store cpu_procinfo 683 movl %edx,R(cpu_feature) # store cpu_feature 684 movl %ecx,R(cpu_feature2) # store cpu_feature2 685 rorl $8,%eax # extract family type 686 andl $15,%eax 687 cmpl $5,%eax 688 jae 1f 689 690 /* less than Pentium; must be 486 */ 691 movl $CPU_486,R(cpu) 692 jmp 3f 6931: 694 /* a Pentium? */ 695 cmpl $5,%eax 696 jne 2f 697 movl $CPU_586,R(cpu) 698 jmp 3f 6992: 700 /* Greater than Pentium...call it a Pentium Pro */ 701 movl $CPU_686,R(cpu) 7023: 703 ret 704 705 706/********************************************************************** 707 * 708 * Create the first page directory and its page tables. 709 * 710 */ 711 712create_pagetables: 713 714/* Find end of kernel image (rounded up to a page boundary). */ 715 movl $R(_end),%esi 716 717/* Include symbols, if any. */ 718 movl R(bootinfo+BI_ESYMTAB),%edi 719 testl %edi,%edi 720 je over_symalloc 721 movl %edi,%esi 722 movl $KERNBASE,%edi 723 addl %edi,R(bootinfo+BI_SYMTAB) 724 addl %edi,R(bootinfo+BI_ESYMTAB) 725over_symalloc: 726 727/* If we are told where the end of the kernel space is, believe it. */ 728 movl R(bootinfo+BI_KERNEND),%edi 729 testl %edi,%edi 730 je no_kernend 731 movl %edi,%esi 732no_kernend: 733 734 addl $PDRMASK,%esi /* Play conservative for now, and */ 735 andl $~PDRMASK,%esi /* ... wrap to next 4M. */ 736 movl %esi,R(KERNend) /* save end of kernel */ 737 movl %esi,R(physfree) /* next free page is at end of kernel */ 738 739/* Allocate Kernel Page Tables */ 740 ALLOCPAGES(NKPT) 741 movl %esi,R(KPTphys) 742 743/* Allocate Page Table Directory */ 744#ifdef PAE 745 /* XXX only need 32 bytes (easier for now) */ 746 ALLOCPAGES(1) 747 movl %esi,R(IdlePDPT) 748#endif 749 ALLOCPAGES(NPGPTD) 750 movl %esi,R(IdlePTD) 751 752/* Allocate KSTACK */ 753 ALLOCPAGES(KSTACK_PAGES) 754 movl %esi,R(p0kpa) 755 addl $KERNBASE, %esi 756 movl %esi, R(proc0kstack) 757 758 ALLOCPAGES(1) /* vm86/bios stack */ 759 movl %esi,R(vm86phystk) 760 761 ALLOCPAGES(3) /* pgtable + ext + IOPAGES */ 762 movl %esi,R(vm86pa) 763 addl $KERNBASE, %esi 764 movl %esi, R(vm86paddr) 765 766#ifdef SMP 767/* Allocate cpu0's private data page */ 768 ALLOCPAGES(1) 769 movl %esi,R(cpu0pp) 770 addl $KERNBASE, %esi 771 movl %esi, R(cpu0prvpage) /* relocated to KVM space */ 772 773/* Allocate SMP page table page */ 774 ALLOCPAGES(1) 775 movl %esi,R(SMPptpa) 776 addl $KERNBASE, %esi 777 movl %esi, R(SMPpt) /* relocated to KVM space */ 778#endif /* SMP */ 779 780/* Map page zero read-write so bios32 calls can use it */ 781 xorl %eax, %eax 782 movl $PG_RW,%edx 783 movl $1,%ecx 784 fillkptphys(%edx) 785 786/* Map read-only from page 1 to the beginning of the kernel text section */ 787 movl $PAGE_SIZE, %eax 788 xorl %edx,%edx 789 movl $R(btext),%ecx 790 addl $PAGE_MASK,%ecx 791 subl %eax,%ecx 792 shrl $PAGE_SHIFT,%ecx 793 fillkptphys(%edx) 794 795/* 796 * Enable PSE and PGE. 797 */ 798#ifndef DISABLE_PSE 799 testl $CPUID_PSE, R(cpu_feature) 800 jz 1f 801 movl $PG_PS, R(pseflag) 802 movl %cr4, %eax 803 orl $CR4_PSE, %eax 804 movl %eax, %cr4 8051: 806#endif 807#ifndef DISABLE_PG_G 808 testl $CPUID_PGE, R(cpu_feature) 809 jz 2f 810 movl $PG_G, R(pgeflag) 811 movl %cr4, %eax 812 orl $CR4_PGE, %eax 813 movl %eax, %cr4 8142: 815#endif 816 817/* 818 * Write page tables for the kernel starting at btext and 819 * until the end. Make sure to map read+write. We do this even 820 * if we've enabled PSE above, we'll just switch the corresponding kernel 821 * PDEs before we turn on paging. 822 * 823 * XXX: We waste some pages here in the PSE case! DON'T BLINDLY REMOVE 824 * THIS! SMP needs the page table to be there to map the kernel P==V. 825 */ 826 movl $R(btext),%eax 827 addl $PAGE_MASK, %eax 828 andl $~PAGE_MASK, %eax 829 movl $PG_RW,%edx 830 movl R(KERNend),%ecx 831 subl %eax,%ecx 832 shrl $PAGE_SHIFT,%ecx 833 fillkptphys(%edx) 834 835/* Map page directory. */ 836#ifdef PAE 837 movl R(IdlePDPT), %eax 838 movl $1, %ecx 839 fillkptphys($PG_RW) 840#endif 841 842 movl R(IdlePTD), %eax 843 movl $NPGPTD, %ecx 844 fillkptphys($PG_RW) 845 846/* Map proc0's KSTACK in the physical way ... */ 847 movl R(p0kpa), %eax 848 movl $(KSTACK_PAGES), %ecx 849 fillkptphys($PG_RW) 850 851/* Map ISA hole */ 852 movl $ISA_HOLE_START, %eax 853 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 854 fillkptphys($PG_RW) 855 856/* Map space for the vm86 region */ 857 movl R(vm86phystk), %eax 858 movl $4, %ecx 859 fillkptphys($PG_RW) 860 861/* Map page 0 into the vm86 page table */ 862 movl $0, %eax 863 movl $0, %ebx 864 movl $1, %ecx 865 fillkpt(R(vm86pa), $PG_RW|PG_U) 866 867/* ...likewise for the ISA hole */ 868 movl $ISA_HOLE_START, %eax 869 movl $ISA_HOLE_START>>PAGE_SHIFT, %ebx 870 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 871 fillkpt(R(vm86pa), $PG_RW|PG_U) 872 873#ifdef SMP 874/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 875 movl R(cpu0pp), %eax 876 movl $1, %ecx 877 fillkptphys($PG_RW) 878 879/* Map SMP page table page into global kmem FWIW */ 880 movl R(SMPptpa), %eax 881 movl $1, %ecx 882 fillkptphys($PG_RW) 883 884/* Map the private page into the SMP page table */ 885 movl R(cpu0pp), %eax 886 movl $0, %ebx /* pte offset = 0 */ 887 movl $1, %ecx /* one private page coming right up */ 888 fillkpt(R(SMPptpa), $PG_RW) 889 890/* ... and put the page table table in the pde. */ 891 movl R(SMPptpa), %eax 892 movl $MPPTDI, %ebx 893 movl $1, %ecx 894 fillkpt(R(IdlePTD), $PG_RW) 895 896/* Fakeup VA for the local apic to allow early traps. */ 897 ALLOCPAGES(1) 898 movl %esi, %eax 899 movl $(NPTEPG-1), %ebx /* pte offset = NTEPG-1 */ 900 movl $1, %ecx /* one private pt coming right up */ 901 fillkpt(R(SMPptpa), $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 $NKPT, %ecx 908 fillkpt(R(IdlePTD), $PG_RW) 909 910/* 911 * For the non-PSE case, install PDEs for PTs covering the KVA. 912 * For the PSE case, do the same, but clobber the ones corresponding 913 * to the kernel (from btext to KERNend) with 4M (2M for PAE) ('PS') 914 * PDEs immediately after. 915 */ 916 movl R(KPTphys), %eax 917 movl $KPTDI, %ebx 918 movl $NKPT, %ecx 919 fillkpt(R(IdlePTD), $PG_RW) 920 cmpl $0,R(pseflag) 921 je done_pde 922 923 movl R(KERNend), %ecx 924 movl $KERNLOAD, %eax 925 subl %eax, %ecx 926 shrl $PDRSHIFT, %ecx 927 movl $(KPTDI+(KERNLOAD/(1 << PDRSHIFT))), %ebx 928 shll $PDESHIFT, %ebx 929 addl R(IdlePTD), %ebx 930 orl $(PG_V|PG_RW|PG_PS), %eax 9311: movl %eax, (%ebx) 932 addl $(1 << PDRSHIFT), %eax 933 addl $PDESIZE, %ebx 934 loop 1b 935 936done_pde: 937/* install a pde recursively mapping page directory as a page table */ 938 movl R(IdlePTD), %eax 939 movl $PTDPTDI, %ebx 940 movl $NPGPTD,%ecx 941 fillkpt(R(IdlePTD), $PG_RW) 942 943#ifdef PAE 944 movl R(IdlePTD), %eax 945 xorl %ebx, %ebx 946 movl $NPGPTD, %ecx 947 fillkpt(R(IdlePDPT), $0x0) 948#endif 949 950 ret 951