locore.s revision 121986
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 121986 2003-11-03 21:53:38Z jhb $ 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_compat.h" 48#include "opt_nfsroot.h" 49#include "opt_pmap.h" 50 51#include <sys/syscall.h> 52#include <sys/reboot.h> 53 54#include <machine/asmacros.h> 55#include <machine/cputypes.h> 56#include <machine/psl.h> 57#include <machine/pmap.h> 58#include <machine/specialreg.h> 59 60#include "assym.s" 61 62/* 63 * XXX 64 * 65 * Note: This version greatly munged to avoid various assembler errors 66 * that may be fixed in newer versions of gas. Perhaps newer versions 67 * will have more pleasant appearance. 68 */ 69 70/* 71 * PTmap is recursive pagemap at top of virtual address space. 72 * Within PTmap, the page directory can be found (third indirection). 73 */ 74 .globl PTmap,PTD,PTDpde 75 .set PTmap,(PTDPTDI << PDRSHIFT) 76 .set PTD,PTmap + (PTDPTDI * PAGE_SIZE) 77 .set PTDpde,PTD + (PTDPTDI * PDESIZE) 78 79#ifdef SMP 80/* 81 * Define layout of per-cpu address space. 82 * This is "constructed" in locore.s on the BSP and in mp_machdep.c 83 * for each AP. DO NOT REORDER THESE WITHOUT UPDATING THE REST! 84 */ 85 .globl SMP_prvspace 86 .set SMP_prvspace,(MPPTDI << PDRSHIFT) 87#endif /* SMP */ 88 89/* 90 * Compiled KERNBASE location and the kernel load address 91 */ 92 .globl kernbase 93 .set kernbase,KERNBASE 94 .globl kernload 95 .set kernload,KERNLOAD 96 97/* 98 * Globals 99 */ 100 .data 101 ALIGN_DATA /* just to be sure */ 102 103 .space 0x2000 /* space for tmpstk - temporary stack */ 104tmpstk: 105 106 .globl bootinfo 107bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 108 109 .globl KERNend 110KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 111physfree: .long 0 /* phys addr of next free page */ 112 113#ifdef SMP 114 .globl cpu0prvpage 115cpu0pp: .long 0 /* phys addr cpu0 private pg */ 116cpu0prvpage: .long 0 /* relocated version */ 117 118 .globl SMPpt 119SMPptpa: .long 0 /* phys addr SMP page table */ 120SMPpt: .long 0 /* relocated version */ 121#endif /* SMP */ 122 123 .globl IdlePTD 124IdlePTD: .long 0 /* phys addr of kernel PTD */ 125 126#ifdef PAE 127 .globl IdlePDPT 128IdlePDPT: .long 0 /* phys addr of kernel PDPT */ 129#endif 130 131#ifdef SMP 132 .globl KPTphys 133#endif 134KPTphys: .long 0 /* phys addr of kernel page tables */ 135 136 .globl proc0uarea, proc0kstack 137proc0uarea: .long 0 /* address of proc 0 uarea space */ 138proc0kstack: .long 0 /* address of proc 0 kstack space */ 139p0upa: .long 0 /* phys addr of proc0's UAREA */ 140p0kpa: .long 0 /* phys addr of proc0's STACK */ 141 142vm86phystk: .long 0 /* PA of vm86/bios stack */ 143 144 .globl vm86paddr, vm86pa 145vm86paddr: .long 0 /* address of vm86 region */ 146vm86pa: .long 0 /* phys addr of vm86 region */ 147 148#ifdef PC98 149 .globl pc98_system_parameter 150pc98_system_parameter: 151 .space 0x240 152#endif 153 154/********************************************************************** 155 * 156 * Some handy macros 157 * 158 */ 159 160#define R(foo) ((foo)-KERNBASE) 161 162#define ALLOCPAGES(foo) \ 163 movl R(physfree), %esi ; \ 164 movl $((foo)*PAGE_SIZE), %eax ; \ 165 addl %esi, %eax ; \ 166 movl %eax, R(physfree) ; \ 167 movl %esi, %edi ; \ 168 movl $((foo)*PAGE_SIZE),%ecx ; \ 169 xorl %eax,%eax ; \ 170 cld ; \ 171 rep ; \ 172 stosb 173 174/* 175 * fillkpt 176 * eax = page frame address 177 * ebx = index into page table 178 * ecx = how many pages to map 179 * base = base address of page dir/table 180 * prot = protection bits 181 */ 182#define fillkpt(base, prot) \ 183 shll $PTESHIFT,%ebx ; \ 184 addl base,%ebx ; \ 185 orl $PG_V,%eax ; \ 186 orl prot,%eax ; \ 1871: movl %eax,(%ebx) ; \ 188 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 189 addl $PTESIZE,%ebx ; /* next pte */ \ 190 loop 1b 191 192/* 193 * fillkptphys(prot) 194 * eax = physical address 195 * ecx = how many pages to map 196 * prot = protection bits 197 */ 198#define fillkptphys(prot) \ 199 movl %eax, %ebx ; \ 200 shrl $PAGE_SHIFT, %ebx ; \ 201 fillkpt(R(KPTphys), prot) 202 203 .text 204/********************************************************************** 205 * 206 * This is where the bootblocks start us, set the ball rolling... 207 * 208 */ 209NON_GPROF_ENTRY(btext) 210 211#ifdef PC98 212 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 213 movl $0xa1400,%esi 214 movl $R(pc98_system_parameter),%edi 215 movl $0x0240,%ecx 216 cld 217 rep 218 movsb 219#else /* IBM-PC */ 220/* Tell the bios to warmboot next time */ 221 movw $0x1234,0x472 222#endif /* PC98 */ 223 224/* Set up a real frame in case the double return in newboot is executed. */ 225 pushl %ebp 226 movl %esp, %ebp 227 228/* Don't trust what the BIOS gives for eflags. */ 229 pushl $PSL_KERNEL 230 popfl 231 232/* 233 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 234 * to set %cs, %ds, %es and %ss. 235 */ 236 mov %ds, %ax 237 mov %ax, %fs 238 mov %ax, %gs 239 240/* 241 * Clear the bss. Not all boot programs do it, and it is our job anyway. 242 * 243 * XXX we don't check that there is memory for our bss and page tables 244 * before using it. 245 * 246 * Note: we must be careful to not overwrite an active gdt or idt. They 247 * inactive from now until we switch to new ones, since we don't load any 248 * more segment registers or permit interrupts until after the switch. 249 */ 250 movl $R(end),%ecx 251 movl $R(edata),%edi 252 subl %edi,%ecx 253 xorl %eax,%eax 254 cld 255 rep 256 stosb 257 258 call recover_bootinfo 259 260/* Get onto a stack that we can trust. */ 261/* 262 * XXX this step is delayed in case recover_bootinfo needs to return via 263 * the old stack, but it need not be, since recover_bootinfo actually 264 * returns via the old frame. 265 */ 266 movl $R(tmpstk),%esp 267 268#ifdef PC98 269 /* pc98_machine_type & M_EPSON_PC98 */ 270 testb $0x02,R(pc98_system_parameter)+220 271 jz 3f 272 /* epson_machine_id <= 0x0b */ 273 cmpb $0x0b,R(pc98_system_parameter)+224 274 ja 3f 275 276 /* count up memory */ 277 movl $0x100000,%eax /* next, talley remaining memory */ 278 movl $0xFFF-0x100,%ecx 2791: movl 0(%eax),%ebx /* save location to check */ 280 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 281 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 282 jne 2f 283 movl %ebx,0(%eax) /* restore memory */ 284 addl $PAGE_SIZE,%eax 285 loop 1b 2862: subl $0x100000,%eax 287 shrl $17,%eax 288 movb %al,R(pc98_system_parameter)+1 2893: 290 291 movw R(pc98_system_parameter+0x86),%ax 292 movw %ax,R(cpu_id) 293#endif 294 295 call identify_cpu 296 call create_pagetables 297 298/* 299 * If the CPU has support for VME, turn it on. 300 */ 301 testl $CPUID_VME, R(cpu_feature) 302 jz 1f 303 movl %cr4, %eax 304 orl $CR4_VME, %eax 305 movl %eax, %cr4 3061: 307 308/* Now enable paging */ 309#ifdef PAE 310 movl R(IdlePDPT), %eax 311 movl %eax, %cr3 312 movl %cr4, %eax 313 orl $CR4_PAE, %eax 314 movl %eax, %cr4 315#else 316 movl R(IdlePTD), %eax 317 movl %eax,%cr3 /* load ptd addr into mmu */ 318#endif 319 movl %cr0,%eax /* get control word */ 320 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 321 movl %eax,%cr0 /* and let's page NOW! */ 322 323 pushl $begin /* jump to high virtualized address */ 324 ret 325 326/* now running relocated at KERNBASE where the system is linked to run */ 327begin: 328 /* set up bootstrap stack */ 329 movl proc0kstack,%eax /* location of in-kernel stack */ 330 /* bootstrap stack end location */ 331 leal (KSTACK_PAGES*PAGE_SIZE-PCB_SIZE)(%eax),%esp 332 333 xorl %ebp,%ebp /* mark end of frames */ 334 335#ifdef PAE 336 movl IdlePDPT,%esi 337#else 338 movl IdlePTD,%esi 339#endif 340 movl %esi,(KSTACK_PAGES*PAGE_SIZE-PCB_SIZE+PCB_CR3)(%eax) 341 342 pushl physfree /* value of first for init386(first) */ 343 call init386 /* wire 386 chip for unix operation */ 344 345 /* 346 * Clean up the stack in a way that db_numargs() understands, so 347 * that backtraces in ddb don't underrun the stack. Traps for 348 * inaccessible memory are more fatal than usual this early. 349 */ 350 addl $4,%esp 351 352 call mi_startup /* autoconfiguration, mountroot etc */ 353 /* NOTREACHED */ 354 addl $0,%esp /* for db_numargs() again */ 355 356/* 357 * Signal trampoline, copied to top of user stack 358 */ 359NON_GPROF_ENTRY(sigcode) 360 calll *SIGF_HANDLER(%esp) 361 leal SIGF_UC(%esp),%eax /* get ucontext */ 362 pushl %eax 363 testl $PSL_VM,UC_EFLAGS(%eax) 364 jne 1f 365 movl UC_GS(%eax),%gs /* restore %gs */ 3661: 367 movl $SYS_sigreturn,%eax 368 pushl %eax /* junk to fake return addr. */ 369 int $0x80 /* enter kernel with args */ 370 /* on stack */ 3711: 372 jmp 1b 373 374#ifdef COMPAT_FREEBSD4 375 ALIGN_TEXT 376freebsd4_sigcode: 377 calll *SIGF_HANDLER(%esp) 378 leal SIGF_UC4(%esp),%eax /* get ucontext */ 379 pushl %eax 380 testl $PSL_VM,UC4_EFLAGS(%eax) 381 jne 1f 382 movl UC4_GS(%eax),%gs /* restore %gs */ 3831: 384 movl $344,%eax /* 4.x SYS_sigreturn */ 385 pushl %eax /* junk to fake return addr. */ 386 int $0x80 /* enter kernel with args */ 387 /* on stack */ 3881: 389 jmp 1b 390#endif 391 392#ifdef COMPAT_43 393 ALIGN_TEXT 394osigcode: 395 call *SIGF_HANDLER(%esp) /* call signal handler */ 396 lea SIGF_SC(%esp),%eax /* get sigcontext */ 397 pushl %eax 398 testl $PSL_VM,SC_PS(%eax) 399 jne 9f 400 movl SC_GS(%eax),%gs /* restore %gs */ 4019: 402 movl $103,%eax /* 3.x SYS_sigreturn */ 403 pushl %eax /* junk to fake return addr. */ 404 int $0x80 /* enter kernel with args */ 4050: jmp 0b 406#endif /* COMPAT_43 */ 407 408 ALIGN_TEXT 409esigcode: 410 411 .data 412 .globl szsigcode 413szsigcode: 414 .long esigcode-sigcode 415#ifdef COMPAT_FREEBSD4 416 .globl szfreebsd4_sigcode 417szfreebsd4_sigcode: 418 .long esigcode-freebsd4_sigcode 419#endif 420#ifdef COMPAT_43 421 .globl szosigcode 422szosigcode: 423 .long esigcode-osigcode 424#endif 425 .text 426 427/********************************************************************** 428 * 429 * Recover the bootinfo passed to us from the boot program 430 * 431 */ 432recover_bootinfo: 433 /* 434 * This code is called in different ways depending on what loaded 435 * and started the kernel. This is used to detect how we get the 436 * arguments from the other code and what we do with them. 437 * 438 * Old disk boot blocks: 439 * (*btext)(howto, bootdev, cyloffset, esym); 440 * [return address == 0, and can NOT be returned to] 441 * [cyloffset was not supported by the FreeBSD boot code 442 * and always passed in as 0] 443 * [esym is also known as total in the boot code, and 444 * was never properly supported by the FreeBSD boot code] 445 * 446 * Old diskless netboot code: 447 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 448 * [return address != 0, and can NOT be returned to] 449 * If we are being booted by this code it will NOT work, 450 * so we are just going to halt if we find this case. 451 * 452 * New uniform boot code: 453 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 454 * [return address != 0, and can be returned to] 455 * 456 * There may seem to be a lot of wasted arguments in here, but 457 * that is so the newer boot code can still load very old kernels 458 * and old boot code can load new kernels. 459 */ 460 461 /* 462 * The old style disk boot blocks fake a frame on the stack and 463 * did an lret to get here. The frame on the stack has a return 464 * address of 0. 465 */ 466 cmpl $0,4(%ebp) 467 je olddiskboot 468 469 /* 470 * We have some form of return address, so this is either the 471 * old diskless netboot code, or the new uniform code. That can 472 * be detected by looking at the 5th argument, if it is 0 473 * we are being booted by the new uniform boot code. 474 */ 475 cmpl $0,24(%ebp) 476 je newboot 477 478 /* 479 * Seems we have been loaded by the old diskless boot code, we 480 * don't stand a chance of running as the diskless structure 481 * changed considerably between the two, so just halt. 482 */ 483 hlt 484 485 /* 486 * We have been loaded by the new uniform boot code. 487 * Let's check the bootinfo version, and if we do not understand 488 * it we return to the loader with a status of 1 to indicate this error 489 */ 490newboot: 491 movl 28(%ebp),%ebx /* &bootinfo.version */ 492 movl BI_VERSION(%ebx),%eax 493 cmpl $1,%eax /* We only understand version 1 */ 494 je 1f 495 movl $1,%eax /* Return status */ 496 leave 497 /* 498 * XXX this returns to our caller's caller (as is required) since 499 * we didn't set up a frame and our caller did. 500 */ 501 ret 502 5031: 504 /* 505 * If we have a kernelname copy it in 506 */ 507 movl BI_KERNELNAME(%ebx),%esi 508 cmpl $0,%esi 509 je 2f /* No kernelname */ 510 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 511 movl $R(kernelname),%edi 512 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 513 je 1f 514 movb $'/',(%edi) 515 incl %edi 516 decl %ecx 5171: 518 cld 519 rep 520 movsb 521 5222: 523 /* 524 * Determine the size of the boot loader's copy of the bootinfo 525 * struct. This is impossible to do properly because old versions 526 * of the struct don't contain a size field and there are 2 old 527 * versions with the same version number. 528 */ 529 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 530 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 531 je got_bi_size /* no, sizeless version */ 532 movl BI_SIZE(%ebx),%ecx 533got_bi_size: 534 535 /* 536 * Copy the common part of the bootinfo struct 537 */ 538 movl %ebx,%esi 539 movl $R(bootinfo),%edi 540 cmpl $BOOTINFO_SIZE,%ecx 541 jbe got_common_bi_size 542 movl $BOOTINFO_SIZE,%ecx 543got_common_bi_size: 544 cld 545 rep 546 movsb 547 548#ifdef NFS_ROOT 549#ifndef BOOTP_NFSV3 550 /* 551 * If we have a nfs_diskless structure copy it in 552 */ 553 movl BI_NFS_DISKLESS(%ebx),%esi 554 cmpl $0,%esi 555 je olddiskboot 556 movl $R(nfs_diskless),%edi 557 movl $NFSDISKLESS_SIZE,%ecx 558 cld 559 rep 560 movsb 561 movl $R(nfs_diskless_valid),%edi 562 movl $1,(%edi) 563#endif 564#endif 565 566 /* 567 * The old style disk boot. 568 * (*btext)(howto, bootdev, cyloffset, esym); 569 * Note that the newer boot code just falls into here to pick 570 * up howto and bootdev, cyloffset and esym are no longer used 571 */ 572olddiskboot: 573 movl 8(%ebp),%eax 574 movl %eax,R(boothowto) 575 movl 12(%ebp),%eax 576 movl %eax,R(bootdev) 577 578 ret 579 580 581/********************************************************************** 582 * 583 * Identify the CPU and initialize anything special about it 584 * 585 */ 586identify_cpu: 587 588 /* Try to toggle alignment check flag; does not exist on 386. */ 589 pushfl 590 popl %eax 591 movl %eax,%ecx 592 orl $PSL_AC,%eax 593 pushl %eax 594 popfl 595 pushfl 596 popl %eax 597 xorl %ecx,%eax 598 andl $PSL_AC,%eax 599 pushl %ecx 600 popfl 601 602 testl %eax,%eax 603 jnz try486 604 605 /* NexGen CPU does not have aligment check flag. */ 606 pushfl 607 movl $0x5555, %eax 608 xorl %edx, %edx 609 movl $2, %ecx 610 clc 611 divl %ecx 612 jz trynexgen 613 popfl 614 movl $CPU_386,R(cpu) 615 jmp 3f 616 617trynexgen: 618 popfl 619 movl $CPU_NX586,R(cpu) 620 movl $0x4778654e,R(cpu_vendor) # store vendor string 621 movl $0x72446e65,R(cpu_vendor+4) 622 movl $0x6e657669,R(cpu_vendor+8) 623 movl $0,R(cpu_vendor+12) 624 jmp 3f 625 626try486: /* Try to toggle identification flag; does not exist on early 486s. */ 627 pushfl 628 popl %eax 629 movl %eax,%ecx 630 xorl $PSL_ID,%eax 631 pushl %eax 632 popfl 633 pushfl 634 popl %eax 635 xorl %ecx,%eax 636 andl $PSL_ID,%eax 637 pushl %ecx 638 popfl 639 640 testl %eax,%eax 641 jnz trycpuid 642 movl $CPU_486,R(cpu) 643 644 /* 645 * Check Cyrix CPU 646 * Cyrix CPUs do not change the undefined flags following 647 * execution of the divide instruction which divides 5 by 2. 648 * 649 * Note: CPUID is enabled on M2, so it passes another way. 650 */ 651 pushfl 652 movl $0x5555, %eax 653 xorl %edx, %edx 654 movl $2, %ecx 655 clc 656 divl %ecx 657 jnc trycyrix 658 popfl 659 jmp 3f /* You may use Intel CPU. */ 660 661trycyrix: 662 popfl 663 /* 664 * IBM Bluelighting CPU also doesn't change the undefined flags. 665 * Because IBM doesn't disclose the information for Bluelighting 666 * CPU, we couldn't distinguish it from Cyrix's (including IBM 667 * brand of Cyrix CPUs). 668 */ 669 movl $0x69727943,R(cpu_vendor) # store vendor string 670 movl $0x736e4978,R(cpu_vendor+4) 671 movl $0x64616574,R(cpu_vendor+8) 672 jmp 3f 673 674trycpuid: /* Use the `cpuid' instruction. */ 675 xorl %eax,%eax 676 cpuid # cpuid 0 677 movl %eax,R(cpu_high) # highest capability 678 movl %ebx,R(cpu_vendor) # store vendor string 679 movl %edx,R(cpu_vendor+4) 680 movl %ecx,R(cpu_vendor+8) 681 movb $0,R(cpu_vendor+12) 682 683 movl $1,%eax 684 cpuid # cpuid 1 685 movl %eax,R(cpu_id) # store cpu_id 686 movl %ebx,R(cpu_procinfo) # store cpu_procinfo 687 movl %edx,R(cpu_feature) # store cpu_feature 688 rorl $8,%eax # extract family type 689 andl $15,%eax 690 cmpl $5,%eax 691 jae 1f 692 693 /* less than Pentium; must be 486 */ 694 movl $CPU_486,R(cpu) 695 jmp 3f 6961: 697 /* a Pentium? */ 698 cmpl $5,%eax 699 jne 2f 700 movl $CPU_586,R(cpu) 701 jmp 3f 7022: 703 /* Greater than Pentium...call it a Pentium Pro */ 704 movl $CPU_686,R(cpu) 7053: 706 ret 707 708 709/********************************************************************** 710 * 711 * Create the first page directory and its page tables. 712 * 713 */ 714 715create_pagetables: 716 717/* Find end of kernel image (rounded up to a page boundary). */ 718 movl $R(_end),%esi 719 720/* Include symbols, if any. */ 721 movl R(bootinfo+BI_ESYMTAB),%edi 722 testl %edi,%edi 723 je over_symalloc 724 movl %edi,%esi 725 movl $KERNBASE,%edi 726 addl %edi,R(bootinfo+BI_SYMTAB) 727 addl %edi,R(bootinfo+BI_ESYMTAB) 728over_symalloc: 729 730/* If we are told where the end of the kernel space is, believe it. */ 731 movl R(bootinfo+BI_KERNEND),%edi 732 testl %edi,%edi 733 je no_kernend 734 movl %edi,%esi 735no_kernend: 736 737 addl $PDRMASK,%esi /* Play conservative for now, and */ 738 andl $~PDRMASK,%esi /* ... wrap to next 4M. */ 739 movl %esi,R(KERNend) /* save end of kernel */ 740 movl %esi,R(physfree) /* next free page is at end of kernel */ 741 742/* Allocate Kernel Page Tables */ 743 ALLOCPAGES(NKPT) 744 movl %esi,R(KPTphys) 745 746/* Allocate Page Table Directory */ 747#ifdef PAE 748 /* XXX only need 32 bytes (easier for now) */ 749 ALLOCPAGES(1) 750 movl %esi,R(IdlePDPT) 751#endif 752 ALLOCPAGES(NPGPTD) 753 movl %esi,R(IdlePTD) 754 755/* Allocate UPAGES */ 756 ALLOCPAGES(UAREA_PAGES) 757 movl %esi,R(p0upa) 758 addl $KERNBASE, %esi 759 movl %esi, R(proc0uarea) 760 761 ALLOCPAGES(KSTACK_PAGES) 762 movl %esi,R(p0kpa) 763 addl $KERNBASE, %esi 764 movl %esi, R(proc0kstack) 765 766 ALLOCPAGES(1) /* vm86/bios stack */ 767 movl %esi,R(vm86phystk) 768 769 ALLOCPAGES(3) /* pgtable + ext + IOPAGES */ 770 movl %esi,R(vm86pa) 771 addl $KERNBASE, %esi 772 movl %esi, R(vm86paddr) 773 774#ifdef SMP 775/* Allocate cpu0's private data page */ 776 ALLOCPAGES(1) 777 movl %esi,R(cpu0pp) 778 addl $KERNBASE, %esi 779 movl %esi, R(cpu0prvpage) /* relocated to KVM space */ 780 781/* Allocate SMP page table page */ 782 ALLOCPAGES(1) 783 movl %esi,R(SMPptpa) 784 addl $KERNBASE, %esi 785 movl %esi, R(SMPpt) /* relocated to KVM space */ 786#endif /* SMP */ 787 788/* Map page zero read-write so bios32 calls can use it */ 789 xorl %eax, %eax 790 movl $PG_RW,%edx 791 movl $1,%ecx 792 fillkptphys(%edx) 793 794/* Map read-only from page 1 to the beginning of the kernel text section */ 795 movl $PAGE_SIZE, %eax 796 xorl %edx,%edx 797 movl $R(btext),%ecx 798 addl $PAGE_MASK,%ecx 799 subl %eax,%ecx 800 shrl $PAGE_SHIFT,%ecx 801 fillkptphys(%edx) 802 803/* 804 * Enable PSE and PGE. 805 */ 806#ifndef DISABLE_PSE 807 testl $CPUID_PSE, R(cpu_feature) 808 jz 1f 809 movl $PG_PS, R(pseflag) 810 movl %cr4, %eax 811 orl $CR4_PSE, %eax 812 movl %eax, %cr4 8131: 814#endif 815#ifndef DISABLE_PG_G 816 testl $CPUID_PGE, R(cpu_feature) 817 jz 2f 818 movl $PG_G, R(pgeflag) 819 movl %cr4, %eax 820 orl $CR4_PGE, %eax 821 movl %eax, %cr4 8222: 823#endif 824 825/* 826 * Write page tables for the kernel starting at btext and 827 * until the end. Make sure to map read+write. We do this even 828 * if we've enabled PSE above, we'll just switch the corresponding kernel 829 * PDEs before we turn on paging. 830 * 831 * XXX: We waste some pages here in the PSE case! DON'T BLINDLY REMOVE 832 * THIS! SMP needs the page table to be there to map the kernel P==V. 833 */ 834 movl $R(btext),%eax 835 addl $PAGE_MASK, %eax 836 andl $~PAGE_MASK, %eax 837 movl $PG_RW,%edx 838 movl R(KERNend),%ecx 839 subl %eax,%ecx 840 shrl $PAGE_SHIFT,%ecx 841 fillkptphys(%edx) 842 843/* Map page directory. */ 844#ifdef PAE 845 movl R(IdlePDPT), %eax 846 movl $1, %ecx 847 fillkptphys($PG_RW) 848#endif 849 850 movl R(IdlePTD), %eax 851 movl $NPGPTD, %ecx 852 fillkptphys($PG_RW) 853 854/* Map proc0's UPAGES in the physical way ... */ 855 movl R(p0upa), %eax 856 movl $(UAREA_PAGES), %ecx 857 fillkptphys($PG_RW) 858 859/* Map proc0's KSTACK in the physical way ... */ 860 movl R(p0kpa), %eax 861 movl $(KSTACK_PAGES), %ecx 862 fillkptphys($PG_RW) 863 864/* Map ISA hole */ 865 movl $ISA_HOLE_START, %eax 866 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 867 fillkptphys($PG_RW) 868 869/* Map space for the vm86 region */ 870 movl R(vm86phystk), %eax 871 movl $4, %ecx 872 fillkptphys($PG_RW) 873 874/* Map page 0 into the vm86 page table */ 875 movl $0, %eax 876 movl $0, %ebx 877 movl $1, %ecx 878 fillkpt(R(vm86pa), $PG_RW|PG_U) 879 880/* ...likewise for the ISA hole */ 881 movl $ISA_HOLE_START, %eax 882 movl $ISA_HOLE_START>>PAGE_SHIFT, %ebx 883 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 884 fillkpt(R(vm86pa), $PG_RW|PG_U) 885 886#ifdef SMP 887/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 888 movl R(cpu0pp), %eax 889 movl $1, %ecx 890 fillkptphys($PG_RW) 891 892/* Map SMP page table page into global kmem FWIW */ 893 movl R(SMPptpa), %eax 894 movl $1, %ecx 895 fillkptphys($PG_RW) 896 897/* Map the private page into the SMP page table */ 898 movl R(cpu0pp), %eax 899 movl $0, %ebx /* pte offset = 0 */ 900 movl $1, %ecx /* one private page coming right up */ 901 fillkpt(R(SMPptpa), $PG_RW) 902 903/* ... and put the page table table in the pde. */ 904 movl R(SMPptpa), %eax 905 movl $MPPTDI, %ebx 906 movl $1, %ecx 907 fillkpt(R(IdlePTD), $PG_RW) 908 909/* Fakeup VA for the local apic to allow early traps. */ 910 ALLOCPAGES(1) 911 movl %esi, %eax 912 movl $(NPTEPG-1), %ebx /* pte offset = NTEPG-1 */ 913 movl $1, %ecx /* one private pt coming right up */ 914 fillkpt(R(SMPptpa), $PG_RW) 915#endif /* SMP */ 916 917/* install a pde for temporary double map of bottom of VA */ 918 movl R(KPTphys), %eax 919 xorl %ebx, %ebx 920 movl $NKPT, %ecx 921 fillkpt(R(IdlePTD), $PG_RW) 922 923/* 924 * For the non-PSE case, install PDEs for PTs covering the kernel. 925 * For the PSE case, do the same, but clobber the ones corresponding 926 * to the kernel (from btext to KERNend) with 4M ('PS') PDEs immediately 927 * after. 928 */ 929 movl R(KPTphys), %eax 930 movl $KPTDI, %ebx 931 movl $NKPT, %ecx 932 fillkpt(R(IdlePTD), $PG_RW) 933 cmpl $0,R(pseflag) 934 je done_pde 935 936 movl R(KERNend), %ecx 937 movl $KERNLOAD, %eax 938 subl %eax, %ecx 939 shrl $PDRSHIFT, %ecx 940 movl $(KPTDI+(KERNLOAD/(1 << PDRSHIFT))), %ebx 941 shll $PDESHIFT, %ebx 942 addl R(IdlePTD), %ebx 943 orl $(PG_V|PG_RW|PG_PS), %eax 9441: movl %eax, (%ebx) 945 addl $(1 << PDRSHIFT), %eax 946 addl $PDESIZE, %ebx 947 loop 1b 948 949done_pde: 950/* install a pde recursively mapping page directory as a page table */ 951 movl R(IdlePTD), %eax 952 movl $PTDPTDI, %ebx 953 movl $NPGPTD,%ecx 954 fillkpt(R(IdlePTD), $PG_RW) 955 956#ifdef PAE 957 movl R(IdlePTD), %eax 958 xorl %ebx, %ebx 959 movl $NPGPTD, %ecx 960 fillkpt(R(IdlePDPT), $0x0) 961#endif 962 963 ret 964