locore.s revision 28808
1295009Sjkim/*- 2280297Sjkim * Copyright (c) 1990 The Regents of the University of California. 3280297Sjkim * All rights reserved. 4280297Sjkim * 5109998Smarkm * This code is derived from software contributed to Berkeley by 6109998Smarkm * William Jolitz. 7109998Smarkm * 8109998Smarkm * Redistribution and use in source and binary forms, with or without 9109998Smarkm * modification, are permitted provided that the following conditions 10109998Smarkm * are met: 11109998Smarkm * 1. Redistributions of source code must retain the above copyright 12109998Smarkm * notice, this list of conditions and the following disclaimer. 13109998Smarkm * 2. Redistributions in binary form must reproduce the above copyright 14280297Sjkim * notice, this list of conditions and the following disclaimer in the 15109998Smarkm * documentation and/or other materials provided with the distribution. 16109998Smarkm * 3. All advertising materials mentioning features or use of this software 17109998Smarkm * must display the following acknowledgement: 18109998Smarkm * This product includes software developed by the University of 19109998Smarkm * California, Berkeley and its contributors. 20109998Smarkm * 4. Neither the name of the University nor the names of its contributors 21109998Smarkm * may be used to endorse or promote products derived from this software 22109998Smarkm * without specific prior written permission. 23109998Smarkm * 24109998Smarkm * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25109998Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26109998Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27109998Smarkm * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28109998Smarkm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29109998Smarkm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30109998Smarkm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31109998Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32109998Smarkm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33109998Smarkm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34109998Smarkm * SUCH DAMAGE. 35109998Smarkm * 36109998Smarkm * from: @(#)locore.s 7.3 (Berkeley) 5/13/91 37109998Smarkm * $Id: locore.s,v 1.95 1997/08/24 00:05:33 fsmp Exp $ 38109998Smarkm * 39109998Smarkm * originally from: locore.s, by William F. Jolitz 40109998Smarkm * 41109998Smarkm * Substantially rewritten by David Greenman, Rod Grimes, 42109998Smarkm * Bruce Evans, Wolfgang Solfrank, Poul-Henning Kamp 43109998Smarkm * and many others. 44109998Smarkm */ 45109998Smarkm 46109998Smarkm#include "apm.h" 47109998Smarkm#include "opt_cpu.h" 48109998Smarkm#include "opt_ddb.h" 49109998Smarkm#include "opt_userconfig.h" 50109998Smarkm 51109998Smarkm#include <sys/syscall.h> 52109998Smarkm#include <sys/reboot.h> 53109998Smarkm 54109998Smarkm#include <machine/asmacros.h> 55109998Smarkm#include <machine/cputypes.h> 56109998Smarkm#include <machine/psl.h> 57109998Smarkm#include <machine/pmap.h> 58109998Smarkm#include <machine/specialreg.h> 59109998Smarkm 60109998Smarkm#include "assym.s" 61280297Sjkim 62109998Smarkm/* 63280297Sjkim * XXX 64280297Sjkim * 65109998Smarkm * Note: This version greatly munged to avoid various assembler errors 66109998Smarkm * that may be fixed in newer versions of gas. Perhaps newer versions 67109998Smarkm * will have more pleasant appearance. 68109998Smarkm */ 69109998Smarkm 70280297Sjkim/* 71280297Sjkim * PTmap is recursive pagemap at top of virtual address space. 72280297Sjkim * Within PTmap, the page directory can be found (third indirection). 73280297Sjkim */ 74109998Smarkm .globl _PTmap,_PTD,_PTDpde 75280297Sjkim .set _PTmap,(PTDPTDI << PDRSHIFT) 76280297Sjkim .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 77280297Sjkim .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 78280297Sjkim 79109998Smarkm/* 80280297Sjkim * APTmap, APTD is the alternate recursive pagemap. 81280297Sjkim * It's used when modifying another process's page tables. 82280297Sjkim */ 83280297Sjkim .globl _APTmap,_APTD,_APTDpde 84109998Smarkm .set _APTmap,APTDPTDI << PDRSHIFT 85109998Smarkm .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 86109998Smarkm .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 87109998Smarkm 88109998Smarkm#ifdef SMP 89 .globl _SMP_prvstart 90 .set _SMP_prvstart,(MPPTDI << PDRSHIFT) 91 92 .globl _SMP_prvpage,_SMP_prvpt,_lapic,_SMP_ioapic 93 .globl _prv_CPAGE1,_prv_CPAGE2,_prv_CPAGE3 94 .globl _idlestack,_idlestack_top 95 .set _SMP_prvpage,_SMP_prvstart 96 .set _SMP_prvpt,_SMP_prvstart + PAGE_SIZE 97 .set _lapic,_SMP_prvstart + (2 * PAGE_SIZE) 98 .set _idlestack,_SMP_prvstart + (3 * PAGE_SIZE) 99 .set _idlestack_top,_SMP_prvstart + (4 * PAGE_SIZE) 100 .set _prv_CPAGE1,_SMP_prvstart + (4 * PAGE_SIZE) 101 .set _prv_CPAGE2,_SMP_prvstart + (5 * PAGE_SIZE) 102 .set _prv_CPAGE3,_SMP_prvstart + (6 * PAGE_SIZE) 103 .set _SMP_ioapic,_SMP_prvstart + (16 * PAGE_SIZE) 104 105 .globl _cpuid,_curproc,_curpcb,_npxproc,_runtime,_cpu_lockid 106 .globl _common_tss,_other_cpus,_my_idlePTD,_ss_tpr 107 .globl _prv_CMAP1,_prv_CMAP2,_prv_CMAP3 108 .set _cpuid,_SMP_prvpage+0 /* [0] */ 109 .set _curproc,_SMP_prvpage+4 /* [1] */ 110 .set _curpcb,_SMP_prvpage+8 /* [2] */ 111 .set _npxproc,_SMP_prvpage+12 /* [3] */ 112 .set _runtime,_SMP_prvpage+16 /* [4,5] */ 113 .set _cpu_lockid,_SMP_prvpage+24 /* [6] */ 114 .set _other_cpus,_SMP_prvpage+28 /* [7] bitmap of available CPUs, 115 excluding ourself */ 116 .set _my_idlePTD,_SMP_prvpage+32 /* [8] */ 117 .set _ss_tpr,_SMP_prvpage+36 /* [9] */ 118 .set _prv_CMAP1,_SMP_prvpage+40 /* [10] */ 119 .set _prv_CMAP2,_SMP_prvpage+44 /* [11] */ 120 .set _prv_CMAP3,_SMP_prvpage+48 /* [12] */ 121 .set _common_tss,_SMP_prvpage+52 /* 102 (ie: 104) bytes long */ 122 123/* Fetch the .set's for the local apic */ 124#include "i386/i386/mp_apicdefs.s" 125 126#endif 127 128/* 129 * Globals 130 */ 131 .data 132 ALIGN_DATA /* just to be sure */ 133 134 .globl HIDENAME(tmpstk) 135 .space 0x2000 /* space for tmpstk - temporary stack */ 136HIDENAME(tmpstk): 137 138 .globl _boothowto,_bootdev 139 140 .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 141 .globl _cpu_high, _cpu_feature 142 143_cpu: .long 0 /* are we 386, 386sx, or 486 */ 144_cpu_id: .long 0 /* stepping ID */ 145_cpu_high: .long 0 /* highest arg to CPUID */ 146_cpu_feature: .long 0 /* features */ 147_cpu_vendor: .space 20 /* CPU origin code */ 148_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 149 150_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 151physfree: .long 0 /* phys addr of next free page */ 152 153#ifdef SMP 154cpu0pp: .long 0 /* phys addr cpu0 private pg */ 155cpu0pt: .long 0 /* phys addr cpu0 private pt */ 156 157 .globl _cpu0prvpage,_cpu0prvpt 158_cpu0prvpage: .long 0 /* relocated version */ 159_cpu0prvpt: .long 0 /* relocated version */ 160#endif /* SMP */ 161 162 .globl _IdlePTD 163_IdlePTD: .long 0 /* phys addr of kernel PTD */ 164 165#ifdef SMP 166 .globl _KPTphys 167#endif 168_KPTphys: .long 0 /* phys addr of kernel page tables */ 169 170 .globl _proc0paddr 171_proc0paddr: .long 0 /* address of proc 0 address space */ 172p0upa: .long 0 /* phys addr of proc0's UPAGES */ 173 174#ifdef BDE_DEBUGGER 175 .globl _bdb_exists /* flag to indicate BDE debugger is present */ 176_bdb_exists: .long 0 177#endif 178 179 180/********************************************************************** 181 * 182 * Some handy macros 183 * 184 */ 185 186#define R(foo) ((foo)-KERNBASE) 187 188#define ALLOCPAGES(foo) \ 189 movl R(physfree), %esi ; \ 190 movl $((foo)*PAGE_SIZE), %eax ; \ 191 addl %esi, %eax ; \ 192 movl %eax, R(physfree) ; \ 193 movl %esi, %edi ; \ 194 movl $((foo)*PAGE_SIZE),%ecx ; \ 195 xorl %eax,%eax ; \ 196 cld ; \ 197 rep ; \ 198 stosb 199 200/* 201 * fillkpt 202 * eax = page frame address 203 * ebx = index into page table 204 * ecx = how many pages to map 205 * base = base address of page dir/table 206 * prot = protection bits 207 */ 208#define fillkpt(base, prot) \ 209 shll $2,%ebx ; \ 210 addl base,%ebx ; \ 211 orl $PG_V,%eax ; \ 212 orl prot,%eax ; \ 2131: movl %eax,(%ebx) ; \ 214 addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 215 addl $4,%ebx ; /* next pte */ \ 216 loop 1b 217 218/* 219 * fillkptphys(prot) 220 * eax = physical address 221 * ecx = how many pages to map 222 * prot = protection bits 223 */ 224#define fillkptphys(prot) \ 225 movl %eax, %ebx ; \ 226 shrl $PAGE_SHIFT, %ebx ; \ 227 fillkpt(R(_KPTphys), prot) 228 229 .text 230/********************************************************************** 231 * 232 * This is where the bootblocks start us, set the ball rolling... 233 * 234 */ 235NON_GPROF_ENTRY(btext) 236 237#ifdef PC98 238 jmp 1f 239 .globl _pc98_system_parameter 240 .org 0x400 241_pc98_system_parameter: 242 .space 0x240 /* BIOS parameter block */ 2431: 244 /* save SYSTEM PARAMETER for resume (NS/T or other) */ 245 movl $0xa1000,%esi 246 movl $0x100000,%edi 247 movl $0x0630,%ecx 248 cld 249 rep 250 movsb 251#else /* IBM-PC */ 252#ifdef BDE_DEBUGGER 253#ifdef BIOS_STEALS_3K 254 cmpl $0x0375c339,0x95504 255#else 256 cmpl $0x0375c339,0x96104 /* XXX - debugger signature */ 257#endif 258 jne 1f 259 movb $1,R(_bdb_exists) 2601: 261#endif 262 263/* Tell the bios to warmboot next time */ 264 movw $0x1234,0x472 265#endif /* PC98 */ 266 267/* Set up a real frame in case the double return in newboot is executed. */ 268 pushl %ebp 269 movl %esp, %ebp 270 271/* Don't trust what the BIOS gives for eflags. */ 272 pushl $PSL_KERNEL 273 popfl 274 275/* 276 * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 277 * to set %cs, %ds, %es and %ss. 278 */ 279 mov %ds, %ax 280 mov %ax, %fs 281 mov %ax, %gs 282 283 call recover_bootinfo 284 285/* Get onto a stack that we can trust. */ 286/* 287 * XXX this step is delayed in case recover_bootinfo needs to return via 288 * the old stack, but it need not be, since recover_bootinfo actually 289 * returns via the old frame. 290 */ 291 movl $R(HIDENAME(tmpstk)),%esp 292 293#ifdef PC98 294 testb $0x02,0x100620 /* pc98_machine_type & M_EPSON_PC98 */ 295 jz 3f 296 cmpb $0x0b,0x100624 /* epson_machine_id <= 0x0b */ 297 ja 3f 298 299 /* count up memory */ 300 movl $0x100000,%eax /* next, talley remaining memory */ 301 movl $0xFFF-0x100,%ecx 3021: movl 0(%eax),%ebx /* save location to check */ 303 movl $0xa55a5aa5,0(%eax) /* write test pattern */ 304 cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 305 jne 2f 306 movl %ebx,0(%eax) /* restore memory */ 307 addl $PAGE_SIZE,%eax 308 loop 1b 3092: subl $0x100000,%eax 310 shrl $17,%eax 311 movb %al,0x100401 3123: 313#endif 314 315 call identify_cpu 316 317/* clear bss */ 318/* 319 * XXX this should be done a little earlier. 320 * 321 * XXX we don't check that there is memory for our bss and page tables 322 * before using it. 323 * 324 * XXX the boot program somewhat bogusly clears the bss. We still have 325 * to do it in case we were unzipped by kzipboot. Then the boot program 326 * only clears kzipboot's bss. 327 * 328 * XXX the gdt and idt are still somewhere in the boot program. We 329 * depend on the convention that the boot program is below 1MB and we 330 * are above 1MB to keep the gdt and idt away from the bss and page 331 * tables. The idt is only used if BDE_DEBUGGER is enabled. 332 */ 333 movl $R(_end),%ecx 334 movl $R(_edata),%edi 335 subl %edi,%ecx 336 xorl %eax,%eax 337 cld 338 rep 339 stosb 340 341#if NAPM > 0 342/* 343 * XXX it's not clear that APM can live in the current environonment. 344 * Only pc-relative addressing works. 345 */ 346 call _apm_setup 347#endif 348 349 call create_pagetables 350 351#ifdef VM86 352/* 353 * If the CPU has support for VME, turn it on. 354 */ 355 testl $CPUID_VME, R(_cpu_feature) 356 jz 1f 357 movl %cr4, %eax 358 orl $CR4_VME, %eax 359 movl %eax, %cr4 3601: 361#endif /* VM86 */ 362 363#ifdef BDE_DEBUGGER 364/* 365 * Adjust as much as possible for paging before enabling paging so that the 366 * adjustments can be traced. 367 */ 368 call bdb_prepare_paging 369#endif 370 371/* Now enable paging */ 372 movl R(_IdlePTD), %eax 373 movl %eax,%cr3 /* load ptd addr into mmu */ 374 movl %cr0,%eax /* get control word */ 375 orl $CR0_PE|CR0_PG,%eax /* enable paging */ 376 movl %eax,%cr0 /* and let's page NOW! */ 377 378#ifdef BDE_DEBUGGER 379/* 380 * Complete the adjustments for paging so that we can keep tracing through 381 * initi386() after the low (physical) addresses for the gdt and idt become 382 * invalid. 383 */ 384 call bdb_commit_paging 385#endif 386 387 pushl $begin /* jump to high virtualized address */ 388 ret 389 390/* now running relocated at KERNBASE where the system is linked to run */ 391begin: 392 /* set up bootstrap stack */ 393 movl _proc0paddr,%esp /* location of in-kernel pages */ 394 addl $UPAGES*PAGE_SIZE,%esp /* bootstrap stack end location */ 395 xorl %eax,%eax /* mark end of frames */ 396 movl %eax,%ebp 397 movl _proc0paddr,%eax 398 movl _IdlePTD, %esi 399 movl %esi,PCB_CR3(%eax) 400 401 movl physfree, %esi 402 pushl %esi /* value of first for init386(first) */ 403 call _init386 /* wire 386 chip for unix operation */ 404 popl %esi 405 406 .globl __ucodesel,__udatasel 407 408 pushl $0 /* unused */ 409 pushl __udatasel /* ss */ 410 pushl $0 /* esp - filled in by execve() */ 411 pushl $PSL_USER /* eflags (IOPL 0, int enab) */ 412 pushl __ucodesel /* cs */ 413 pushl $0 /* eip - filled in by execve() */ 414 subl $(12*4),%esp /* space for rest of registers */ 415 416 pushl %esp /* call main with frame pointer */ 417 call _main /* autoconfiguration, mountroot etc */ 418 419 hlt /* never returns to here */ 420 421/* 422 * When starting init, call this to configure the process for user 423 * mode. This will be inherited by other processes. 424 */ 425NON_GPROF_ENTRY(prepare_usermode) 426 /* 427 * Now we've run main() and determined what cpu-type we are, we can 428 * enable write protection and alignment checking on i486 cpus and 429 * above. 430 */ 431#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) 432 cmpl $CPUCLASS_386,_cpu_class 433 je 1f 434 movl %cr0,%eax /* get control word */ 435 orl $CR0_WP|CR0_AM,%eax /* enable i486 features */ 436 movl %eax,%cr0 /* and do it */ 4371: 438#endif 439 /* 440 * on return from main(), we are process 1 441 * set up address space and stack so that we can 'return' to user mode 442 */ 443 movl __ucodesel,%eax 444 movl __udatasel,%ecx 445 446#if 0 447 movl %cx,%ds 448#endif 449 movl %cx,%es 450 movl %ax,%fs /* double map cs to fs */ 451 movl %cx,%gs /* and ds to gs */ 452 ret /* goto user! */ 453 454 455#define LCALL(x,y) .byte 0x9a ; .long y ; .word x 456 457/* 458 * Signal trampoline, copied to top of user stack 459 */ 460NON_GPROF_ENTRY(sigcode) 461 call SIGF_HANDLER(%esp) 462 lea SIGF_SC(%esp),%eax /* scp (the call may have clobbered the */ 463 /* copy at 8(%esp)) */ 464 pushl %eax 465 pushl %eax /* junk to fake return address */ 466 movl $SYS_sigreturn,%eax /* sigreturn() */ 467 LCALL(0x7,0) /* enter kernel with args on stack */ 468 hlt /* never gets here */ 469 ALIGN_TEXT 470_esigcode: 471 472 .data 473 .globl _szsigcode 474_szsigcode: 475 .long _esigcode-_sigcode 476 .text 477 478/********************************************************************** 479 * 480 * Recover the bootinfo passed to us from the boot program 481 * 482 */ 483recover_bootinfo: 484 /* 485 * This code is called in different ways depending on what loaded 486 * and started the kernel. This is used to detect how we get the 487 * arguments from the other code and what we do with them. 488 * 489 * Old disk boot blocks: 490 * (*btext)(howto, bootdev, cyloffset, esym); 491 * [return address == 0, and can NOT be returned to] 492 * [cyloffset was not supported by the FreeBSD boot code 493 * and always passed in as 0] 494 * [esym is also known as total in the boot code, and 495 * was never properly supported by the FreeBSD boot code] 496 * 497 * Old diskless netboot code: 498 * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 499 * [return address != 0, and can NOT be returned to] 500 * If we are being booted by this code it will NOT work, 501 * so we are just going to halt if we find this case. 502 * 503 * New uniform boot code: 504 * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 505 * [return address != 0, and can be returned to] 506 * 507 * There may seem to be a lot of wasted arguments in here, but 508 * that is so the newer boot code can still load very old kernels 509 * and old boot code can load new kernels. 510 */ 511 512 /* 513 * The old style disk boot blocks fake a frame on the stack and 514 * did an lret to get here. The frame on the stack has a return 515 * address of 0. 516 */ 517 cmpl $0,4(%ebp) 518 je olddiskboot 519 520 /* 521 * We have some form of return address, so this is either the 522 * old diskless netboot code, or the new uniform code. That can 523 * be detected by looking at the 5th argument, if it is 0 524 * we are being booted by the new uniform boot code. 525 */ 526 cmpl $0,24(%ebp) 527 je newboot 528 529 /* 530 * Seems we have been loaded by the old diskless boot code, we 531 * don't stand a chance of running as the diskless structure 532 * changed considerably between the two, so just halt. 533 */ 534 hlt 535 536 /* 537 * We have been loaded by the new uniform boot code. 538 * Let's check the bootinfo version, and if we do not understand 539 * it we return to the loader with a status of 1 to indicate this error 540 */ 541newboot: 542 movl 28(%ebp),%ebx /* &bootinfo.version */ 543 movl BI_VERSION(%ebx),%eax 544 cmpl $1,%eax /* We only understand version 1 */ 545 je 1f 546 movl $1,%eax /* Return status */ 547 leave 548 /* 549 * XXX this returns to our caller's caller (as is required) since 550 * we didn't set up a frame and our caller did. 551 */ 552 ret 553 5541: 555 /* 556 * If we have a kernelname copy it in 557 */ 558 movl BI_KERNELNAME(%ebx),%esi 559 cmpl $0,%esi 560 je 2f /* No kernelname */ 561 movl $MAXPATHLEN,%ecx /* Brute force!!! */ 562 movl $R(_kernelname),%edi 563 cmpb $'/',(%esi) /* Make sure it starts with a slash */ 564 je 1f 565 movb $'/',(%edi) 566 incl %edi 567 decl %ecx 5681: 569 cld 570 rep 571 movsb 572 5732: 574 /* 575 * Determine the size of the boot loader's copy of the bootinfo 576 * struct. This is impossible to do properly because old versions 577 * of the struct don't contain a size field and there are 2 old 578 * versions with the same version number. 579 */ 580 movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 581 testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 582 je got_bi_size /* no, sizeless version */ 583 movl BI_SIZE(%ebx),%ecx 584got_bi_size: 585 586 /* 587 * Copy the common part of the bootinfo struct 588 */ 589 movl %ebx,%esi 590 movl $R(_bootinfo),%edi 591 cmpl $BOOTINFO_SIZE,%ecx 592 jbe got_common_bi_size 593 movl $BOOTINFO_SIZE,%ecx 594got_common_bi_size: 595 cld 596 rep 597 movsb 598 599#ifdef NFS 600#ifndef BOOTP_NFSV3 601 /* 602 * If we have a nfs_diskless structure copy it in 603 */ 604 movl BI_NFS_DISKLESS(%ebx),%esi 605 cmpl $0,%esi 606 je olddiskboot 607 movl $R(_nfs_diskless),%edi 608 movl $NFSDISKLESS_SIZE,%ecx 609 cld 610 rep 611 movsb 612 movl $R(_nfs_diskless_valid),%edi 613 movl $1,(%edi) 614#endif 615#endif 616 617 /* 618 * The old style disk boot. 619 * (*btext)(howto, bootdev, cyloffset, esym); 620 * Note that the newer boot code just falls into here to pick 621 * up howto and bootdev, cyloffset and esym are no longer used 622 */ 623olddiskboot: 624 movl 8(%ebp),%eax 625 movl %eax,R(_boothowto) 626 movl 12(%ebp),%eax 627 movl %eax,R(_bootdev) 628 629#if defined(USERCONFIG_BOOT) && defined(USERCONFIG) 630#ifdef PC98 631 movl $0x90200, %esi 632#else 633 movl $0x10200, %esi 634#endif 635 movl $R(_userconfig_from_boot),%edi 636 movl $512,%ecx 637 cld 638 rep 639 movsb 640#endif /* USERCONFIG_BOOT */ 641 642 ret 643 644 645/********************************************************************** 646 * 647 * Identify the CPU and initialize anything special about it 648 * 649 */ 650identify_cpu: 651 652 /* Try to toggle alignment check flag; does not exist on 386. */ 653 pushfl 654 popl %eax 655 movl %eax,%ecx 656 orl $PSL_AC,%eax 657 pushl %eax 658 popfl 659 pushfl 660 popl %eax 661 xorl %ecx,%eax 662 andl $PSL_AC,%eax 663 pushl %ecx 664 popfl 665 666 testl %eax,%eax 667 jnz try486 668 669 /* NexGen CPU does not have aligment check flag. */ 670 pushfl 671 movl $0x5555, %eax 672 xorl %edx, %edx 673 movl $2, %ecx 674 clc 675 divl %ecx 676 jz trynexgen 677 popfl 678 movl $CPU_386,R(_cpu) 679 jmp 3f 680 681trynexgen: 682 popfl 683 movl $CPU_NX586,R(_cpu) 684 movl $0x4778654e,R(_cpu_vendor) # store vendor string 685 movl $0x72446e65,R(_cpu_vendor+4) 686 movl $0x6e657669,R(_cpu_vendor+8) 687 movl $0,R(_cpu_vendor+12) 688 jmp 3f 689 690try486: /* Try to toggle identification flag; does not exist on early 486s. */ 691 pushfl 692 popl %eax 693 movl %eax,%ecx 694 xorl $PSL_ID,%eax 695 pushl %eax 696 popfl 697 pushfl 698 popl %eax 699 xorl %ecx,%eax 700 andl $PSL_ID,%eax 701 pushl %ecx 702 popfl 703 704 testl %eax,%eax 705 jnz trycpuid 706 movl $CPU_486,R(_cpu) 707 708 /* 709 * Check Cyrix CPU 710 * Cyrix CPUs do not change the undefined flags following 711 * execution of the divide instruction which divides 5 by 2. 712 * 713 * Note: CPUID is enabled on M2, so it passes another way. 714 */ 715 pushfl 716 movl $0x5555, %eax 717 xorl %edx, %edx 718 movl $2, %ecx 719 clc 720 divl %ecx 721 jnc trycyrix 722 popfl 723 jmp 3f /* You may use Intel CPU. */ 724 725trycyrix: 726 popfl 727 /* 728 * IBM Bluelighting CPU also doesn't change the undefined flags. 729 * Because IBM doesn't disclose the information for Bluelighting 730 * CPU, we couldn't distinguish it from Cyrix's (including IBM 731 * brand of Cyrix CPUs). 732 */ 733 movl $0x69727943,R(_cpu_vendor) # store vendor string 734 movl $0x736e4978,R(_cpu_vendor+4) 735 movl $0x64616574,R(_cpu_vendor+8) 736 jmp 3f 737 738trycpuid: /* Use the `cpuid' instruction. */ 739 xorl %eax,%eax 740 .byte 0x0f,0xa2 # cpuid 0 741 movl %eax,R(_cpu_high) # highest capability 742 movl %ebx,R(_cpu_vendor) # store vendor string 743 movl %edx,R(_cpu_vendor+4) 744 movl %ecx,R(_cpu_vendor+8) 745 movb $0,R(_cpu_vendor+12) 746 747 movl $1,%eax 748 .byte 0x0f,0xa2 # cpuid 1 749 movl %eax,R(_cpu_id) # store cpu_id 750 movl %edx,R(_cpu_feature) # store cpu_feature 751 rorl $8,%eax # extract family type 752 andl $15,%eax 753 cmpl $5,%eax 754 jae 1f 755 756 /* less than Pentium; must be 486 */ 757 movl $CPU_486,R(_cpu) 758 jmp 3f 7591: 760 /* a Pentium? */ 761 cmpl $5,%eax 762 jne 2f 763 movl $CPU_586,R(_cpu) 764 jmp 3f 7652: 766 /* Greater than Pentium...call it a Pentium Pro */ 767 movl $CPU_686,R(_cpu) 7683: 769 ret 770 771 772/********************************************************************** 773 * 774 * Create the first page directory and its page tables. 775 * 776 */ 777 778create_pagetables: 779 780 testl $CPUID_PGE, R(_cpu_feature) 781 jz 1f 782 movl %cr4, %eax 783 orl $CR4_PGE, %eax 784 movl %eax, %cr4 7851: 786 787/* Find end of kernel image (rounded up to a page boundary). */ 788 movl $R(_end),%esi 789 790/* include symbols in "kernel image" if they are loaded and useful */ 791#ifdef DDB 792 movl R(_bootinfo+BI_ESYMTAB),%edi 793 testl %edi,%edi 794 je over_symalloc 795 movl %edi,%esi 796 movl $KERNBASE,%edi 797 addl %edi,R(_bootinfo+BI_SYMTAB) 798 addl %edi,R(_bootinfo+BI_ESYMTAB) 799over_symalloc: 800#endif 801 802 addl $PAGE_MASK,%esi 803 andl $~PAGE_MASK,%esi 804 movl %esi,R(_KERNend) /* save end of kernel */ 805 movl %esi,R(physfree) /* next free page is at end of kernel */ 806 807/* Allocate Kernel Page Tables */ 808 ALLOCPAGES(NKPT) 809 movl %esi,R(_KPTphys) 810 811/* Allocate Page Table Directory */ 812 ALLOCPAGES(1) 813 movl %esi,R(_IdlePTD) 814 815/* Allocate UPAGES */ 816 ALLOCPAGES(UPAGES) 817 movl %esi,R(p0upa) 818 addl $KERNBASE, %esi 819 movl %esi, R(_proc0paddr) 820 821#ifdef SMP 822/* Allocate cpu0's private data page */ 823 ALLOCPAGES(1) 824 movl %esi,R(cpu0pp) 825 addl $KERNBASE, %esi 826 movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 827 828/* Allocate cpu0's private page table for mapping priv page, apic, etc */ 829 ALLOCPAGES(1) 830 movl %esi,R(cpu0pt) 831 addl $KERNBASE, %esi 832 movl %esi, R(_cpu0prvpt) /* relocated to KVM space */ 833#endif /* SMP */ 834 835/* Map read-only from zero to the end of the kernel text section */ 836 xorl %eax, %eax 837#ifdef BDE_DEBUGGER 838/* If the debugger is present, actually map everything read-write. */ 839 cmpl $0,R(_bdb_exists) 840 jne map_read_write 841#endif 842 xorl %edx,%edx 843 844#if !defined(SMP) 845 testl $CPUID_PGE, R(_cpu_feature) 846 jz 2f 847 orl $PG_G,%edx 848#endif 849 8502: movl $R(_etext),%ecx 851 addl $PAGE_MASK,%ecx 852 shrl $PAGE_SHIFT,%ecx 853 fillkptphys(%edx) 854 855/* Map read-write, data, bss and symbols */ 856 movl $R(_etext),%eax 857 addl $PAGE_MASK, %eax 858 andl $~PAGE_MASK, %eax 859map_read_write: 860 movl $PG_RW,%edx 861#if !defined(SMP) 862 testl $CPUID_PGE, R(_cpu_feature) 863 jz 1f 864 orl $PG_G,%edx 865#endif 866 8671: movl R(_KERNend),%ecx 868 subl %eax,%ecx 869 shrl $PAGE_SHIFT,%ecx 870 fillkptphys(%edx) 871 872/* Map page directory. */ 873 movl R(_IdlePTD), %eax 874 movl $1, %ecx 875 fillkptphys($PG_RW) 876 877/* Map proc0's UPAGES in the physical way ... */ 878 movl R(p0upa), %eax 879 movl $UPAGES, %ecx 880 fillkptphys($PG_RW) 881 882/* Map ISA hole */ 883 movl $ISA_HOLE_START, %eax 884 movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 885 fillkptphys($PG_RW) 886 887#ifdef SMP 888/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 889 movl R(cpu0pp), %eax 890 movl $1, %ecx 891 fillkptphys($PG_RW) 892 893/* Map cpu0's private page table into global kmem FWIW */ 894 movl R(cpu0pt), %eax 895 movl $1, %ecx 896 fillkptphys($PG_RW) 897 898/* Map the private page into the private page table into private space */ 899 movl R(cpu0pp), %eax 900 movl $0, %ebx /* pte offset = 0 */ 901 movl $1, %ecx /* one private page coming right up */ 902 fillkpt(R(cpu0pt), $PG_RW) 903 904/* Map the page table page into private space */ 905 movl R(cpu0pt), %eax 906 movl $1, %ebx /* pte offset = 1 */ 907 movl $1, %ecx /* one private pt coming right up */ 908 fillkpt(R(cpu0pt), $PG_RW) 909 910/* ... and put the page table table in the pde. */ 911 movl R(cpu0pt), %eax 912 movl $MPPTDI, %ebx 913 movl $1, %ecx 914 fillkpt(R(_IdlePTD), $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 $1, %ecx 921 fillkpt(R(_IdlePTD), $PG_RW) 922 923/* install pde's for pt's */ 924 movl R(_KPTphys), %eax 925 movl $KPTDI, %ebx 926 movl $NKPT, %ecx 927 fillkpt(R(_IdlePTD), $PG_RW) 928 929/* install a pde recursively mapping page directory as a page table */ 930 movl R(_IdlePTD), %eax 931 movl $PTDPTDI, %ebx 932 movl $1,%ecx 933 fillkpt(R(_IdlePTD), $PG_RW) 934 935 ret 936 937#ifdef BDE_DEBUGGER 938bdb_prepare_paging: 939 cmpl $0,R(_bdb_exists) 940 je bdb_prepare_paging_exit 941 942 subl $6,%esp 943 944 /* 945 * Copy and convert debugger entries from the bootstrap gdt and idt 946 * to the kernel gdt and idt. Everything is still in low memory. 947 * Tracing continues to work after paging is enabled because the 948 * low memory addresses remain valid until everything is relocated. 949 * However, tracing through the setidt() that initializes the trace 950 * trap will crash. 951 */ 952 sgdt (%esp) 953 movl 2(%esp),%esi /* base address of bootstrap gdt */ 954 movl $R(_gdt),%edi 955 movl %edi,2(%esp) /* prepare to load kernel gdt */ 956 movl $8*18/4,%ecx 957 cld 958 rep /* copy gdt */ 959 movsl 960 movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 961 movb $0x92,-8+5(%edi) 962 lgdt (%esp) 963 964 sidt (%esp) 965 movl 2(%esp),%esi /* base address of current idt */ 966 movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 967 movw 8(%esi),%ax 968 movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 969 movl 8+2(%esi),%eax 970 movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 971 movl 24+4(%esi),%eax /* same for bpt descriptor */ 972 movw 24(%esi),%ax 973 movl %eax,R(bdb_bpt_ljmp+1) 974 movl 24+2(%esi),%eax 975 movw %ax,R(bdb_bpt_ljmp+5) 976 movl $R(_idt),%edi 977 movl %edi,2(%esp) /* prepare to load kernel idt */ 978 movl $8*4/4,%ecx 979 cld 980 rep /* copy idt */ 981 movsl 982 lidt (%esp) 983 984 addl $6,%esp 985 986bdb_prepare_paging_exit: 987 ret 988 989/* Relocate debugger gdt entries and gdt and idt pointers. */ 990bdb_commit_paging: 991 cmpl $0,_bdb_exists 992 je bdb_commit_paging_exit 993 994 movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 995 movl $9,%ecx 996reloc_gdt: 997 movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 998 addl $8,%eax /* now KERNBASE>>24 */ 999 loop reloc_gdt 1000 1001 subl $6,%esp 1002 sgdt (%esp) 1003 addl $KERNBASE,2(%esp) 1004 lgdt (%esp) 1005 sidt (%esp) 1006 addl $KERNBASE,2(%esp) 1007 lidt (%esp) 1008 addl $6,%esp 1009 1010 int $3 1011 1012bdb_commit_paging_exit: 1013 ret 1014 1015#endif /* BDE_DEBUGGER */ 1016