locore.s revision 61422
14Srgrimes/*- 24Srgrimes * Copyright (c) 1990 The Regents of the University of California. 34Srgrimes * All rights reserved. 44Srgrimes * 54Srgrimes * This code is derived from software contributed to Berkeley by 64Srgrimes * William Jolitz. 74Srgrimes * 84Srgrimes * Redistribution and use in source and binary forms, with or without 94Srgrimes * modification, are permitted provided that the following conditions 104Srgrimes * are met: 114Srgrimes * 1. Redistributions of source code must retain the above copyright 124Srgrimes * notice, this list of conditions and the following disclaimer. 134Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 144Srgrimes * notice, this list of conditions and the following disclaimer in the 154Srgrimes * documentation and/or other materials provided with the distribution. 164Srgrimes * 3. All advertising materials mentioning features or use of this software 174Srgrimes * must display the following acknowledgement: 184Srgrimes * This product includes software developed by the University of 194Srgrimes * California, Berkeley and its contributors. 204Srgrimes * 4. Neither the name of the University nor the names of its contributors 214Srgrimes * may be used to endorse or promote products derived from this software 224Srgrimes * without specific prior written permission. 234Srgrimes * 244Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 254Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 264Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 274Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 284Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 294Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 304Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 314Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 324Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 334Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 344Srgrimes * SUCH DAMAGE. 354Srgrimes * 36556Srgrimes * from: @(#)locore.s 7.3 (Berkeley) 5/13/91 3750477Speter * $FreeBSD: head/sys/i386/i386/locore.s 61422 2000-06-08 17:53:43Z bde $ 3815392Sphk * 39757Sdg * originally from: locore.s, by William F. Jolitz 40757Sdg * 41757Sdg * Substantially rewritten by David Greenman, Rod Grimes, 4215392Sphk * Bruce Evans, Wolfgang Solfrank, Poul-Henning Kamp 4315392Sphk * and many others. 444Srgrimes */ 454Srgrimes 4632358Seivind#include "opt_bootp.h" 4737272Sjmg#include "opt_nfsroot.h" 4814835Sbde 4914835Sbde#include <sys/syscall.h> 505908Sbde#include <sys/reboot.h> 514Srgrimes 5214835Sbde#include <machine/asmacros.h> 5314835Sbde#include <machine/cputypes.h> 5414835Sbde#include <machine/psl.h> 5515543Sphk#include <machine/pmap.h> 5614835Sbde#include <machine/specialreg.h> 5714835Sbde 5814835Sbde#include "assym.s" 5914835Sbde 604Srgrimes/* 61757Sdg * XXX 62757Sdg * 634Srgrimes * Note: This version greatly munged to avoid various assembler errors 644Srgrimes * that may be fixed in newer versions of gas. Perhaps newer versions 654Srgrimes * will have more pleasant appearance. 664Srgrimes */ 674Srgrimes 68200Sdg/* 694Srgrimes * PTmap is recursive pagemap at top of virtual address space. 704Srgrimes * Within PTmap, the page directory can be found (third indirection). 714Srgrimes */ 723861Sbde .globl _PTmap,_PTD,_PTDpde 7315543Sphk .set _PTmap,(PTDPTDI << PDRSHIFT) 7415543Sphk .set _PTD,_PTmap + (PTDPTDI * PAGE_SIZE) 75757Sdg .set _PTDpde,_PTD + (PTDPTDI * PDESIZE) 76592Srgrimes 773861Sbde/* 784Srgrimes * APTmap, APTD is the alternate recursive pagemap. 794Srgrimes * It's used when modifying another process's page tables. 804Srgrimes */ 81592Srgrimes .globl _APTmap,_APTD,_APTDpde 82592Srgrimes .set _APTmap,APTDPTDI << PDRSHIFT 8315543Sphk .set _APTD,_APTmap + (APTDPTDI * PAGE_SIZE) 84757Sdg .set _APTDpde,_PTD + (APTDPTDI * PDESIZE) 854Srgrimes 864Srgrimes/* 87556Srgrimes * Globals 88556Srgrimes */ 89556Srgrimes .data 9014835Sbde ALIGN_DATA /* just to be sure */ 91134Sdg 9225083Sjdp .globl HIDENAME(tmpstk) 9313729Sdg .space 0x2000 /* space for tmpstk - temporary stack */ 9425083SjdpHIDENAME(tmpstk): 953842Sdg 963861Sbde .globl _boothowto,_bootdev 97134Sdg 9815565Sphk .globl _cpu,_cpu_vendor,_cpu_id,_bootinfo 996308Sphk .globl _cpu_high, _cpu_feature 1002783Ssos 10146129Sluoqi_cpu: .long 0 /* are we 386, 386sx, or 486 */ 1022216Sbde_cpu_id: .long 0 /* stepping ID */ 1036308Sphk_cpu_high: .long 0 /* highest arg to CPUID */ 1046308Sphk_cpu_feature: .long 0 /* features */ 1052216Sbde_cpu_vendor: .space 20 /* CPU origin code */ 1065908Sbde_bootinfo: .space BOOTINFO_SIZE /* bootinfo that we can handle */ 1074Srgrimes 108757Sdg_KERNend: .long 0 /* phys addr end of kernel (just after bss) */ 10915428Sphkphysfree: .long 0 /* phys addr of next free page */ 110757Sdg 11126812Speter#ifdef SMP 11246129Sluoqi .globl _cpu0prvpage 11325164Spetercpu0pp: .long 0 /* phys addr cpu0 private pg */ 11446129Sluoqi_cpu0prvpage: .long 0 /* relocated version */ 11525164Speter 11646129Sluoqi .globl _SMPpt 11746129SluoqiSMPptpa: .long 0 /* phys addr SMP page table */ 11846129Sluoqi_SMPpt: .long 0 /* relocated version */ 11926812Speter#endif /* SMP */ 12025164Speter 1213861Sbde .globl _IdlePTD 122757Sdg_IdlePTD: .long 0 /* phys addr of kernel PTD */ 1233861Sbde 12426812Speter#ifdef SMP 12526812Speter .globl _KPTphys 12626812Speter#endif 127757Sdg_KPTphys: .long 0 /* phys addr of kernel page tables */ 1284Srgrimes 129757Sdg .globl _proc0paddr 130757Sdg_proc0paddr: .long 0 /* address of proc 0 address space */ 13124693Speterp0upa: .long 0 /* phys addr of proc0's UPAGES */ 132134Sdg 13337889Sjlemonvm86phystk: .long 0 /* PA of vm86/bios stack */ 13437889Sjlemon 13534840Sjlemon .globl _vm86paddr, _vm86pa 13634840Sjlemon_vm86paddr: .long 0 /* address of vm86 region */ 13734840Sjlemon_vm86pa: .long 0 /* phys addr of vm86 region */ 13834840Sjlemon 13915428Sphk#ifdef BDE_DEBUGGER 14015428Sphk .globl _bdb_exists /* flag to indicate BDE debugger is present */ 14115428Sphk_bdb_exists: .long 0 14215428Sphk#endif 143718Swollman 14443434Skato#ifdef PC98 14543434Skato .globl _pc98_system_parameter 14643434Skato_pc98_system_parameter: 14743434Skato .space 0x240 14843434Skato#endif 14915428Sphk 15015392Sphk/********************************************************************** 15115392Sphk * 15215392Sphk * Some handy macros 15315392Sphk * 154556Srgrimes */ 155134Sdg 15615392Sphk#define R(foo) ((foo)-KERNBASE) 15715392Sphk 15815392Sphk#define ALLOCPAGES(foo) \ 15915392Sphk movl R(physfree), %esi ; \ 16015543Sphk movl $((foo)*PAGE_SIZE), %eax ; \ 16115392Sphk addl %esi, %eax ; \ 16215392Sphk movl %eax, R(physfree) ; \ 16315392Sphk movl %esi, %edi ; \ 16415543Sphk movl $((foo)*PAGE_SIZE),%ecx ; \ 16515392Sphk xorl %eax,%eax ; \ 16615428Sphk cld ; \ 16715428Sphk rep ; \ 16815428Sphk stosb 16915392Sphk 170134Sdg/* 17115392Sphk * fillkpt 17215565Sphk * eax = page frame address 17315565Sphk * ebx = index into page table 17415392Sphk * ecx = how many pages to map 17515565Sphk * base = base address of page dir/table 17615565Sphk * prot = protection bits 177134Sdg */ 17815565Sphk#define fillkpt(base, prot) \ 17919621Sdyson shll $2,%ebx ; \ 18019621Sdyson addl base,%ebx ; \ 18119621Sdyson orl $PG_V,%eax ; \ 18219621Sdyson orl prot,%eax ; \ 18315565Sphk1: movl %eax,(%ebx) ; \ 18415565Sphk addl $PAGE_SIZE,%eax ; /* increment physical address */ \ 18515565Sphk addl $4,%ebx ; /* next pte */ \ 18615428Sphk loop 1b 18715392Sphk 18815565Sphk/* 18915565Sphk * fillkptphys(prot) 19015565Sphk * eax = physical address 19115565Sphk * ecx = how many pages to map 19215565Sphk * prot = protection bits 19315565Sphk */ 19415565Sphk#define fillkptphys(prot) \ 19515565Sphk movl %eax, %ebx ; \ 19615565Sphk shrl $PAGE_SHIFT, %ebx ; \ 19715565Sphk fillkpt(R(_KPTphys), prot) 19815565Sphk 19915392Sphk .text 20015392Sphk/********************************************************************** 20115392Sphk * 20215392Sphk * This is where the bootblocks start us, set the ball rolling... 20315392Sphk * 20415392Sphk */ 2051321SdgNON_GPROF_ENTRY(btext) 2064Srgrimes 20724112Skato#ifdef PC98 20824112Skato /* save SYSTEM PARAMETER for resume (NS/T or other) */ 20943434Skato movl $0xa1400,%esi 21043434Skato movl $R(_pc98_system_parameter),%edi 21143434Skato movl $0x0240,%ecx 21224112Skato cld 21324112Skato rep 21424112Skato movsb 21524112Skato#else /* IBM-PC */ 21615428Sphk#ifdef BDE_DEBUGGER 21715428Sphk#ifdef BIOS_STEALS_3K 21815428Sphk cmpl $0x0375c339,0x95504 21915428Sphk#else 22015428Sphk cmpl $0x0375c339,0x96104 /* XXX - debugger signature */ 22115428Sphk#endif 22215428Sphk jne 1f 22315428Sphk movb $1,R(_bdb_exists) 22415428Sphk1: 22515428Sphk#endif 22615392Sphk/* Tell the bios to warmboot next time */ 22715392Sphk movw $0x1234,0x472 22854128Skato#endif /* PC98 */ 22915392Sphk 23015428Sphk/* Set up a real frame in case the double return in newboot is executed. */ 2313384Srgrimes pushl %ebp 2323384Srgrimes movl %esp, %ebp 2333384Srgrimes 23415392Sphk/* Don't trust what the BIOS gives for eflags. */ 2355603Sbde pushl $PSL_KERNEL 2362486Sdg popfl 23715428Sphk 23815428Sphk/* 23915428Sphk * Don't trust what the BIOS gives for %fs and %gs. Trust the bootstrap 24015428Sphk * to set %cs, %ds, %es and %ss. 24115428Sphk */ 24215428Sphk mov %ds, %ax 2434217Sphk mov %ax, %fs 2444217Sphk mov %ax, %gs 2454217Sphk 24615392Sphk call recover_bootinfo 24715392Sphk 24815428Sphk/* Get onto a stack that we can trust. */ 24915428Sphk/* 25015428Sphk * XXX this step is delayed in case recover_bootinfo needs to return via 25115428Sphk * the old stack, but it need not be, since recover_bootinfo actually 25215428Sphk * returns via the old frame. 25315428Sphk */ 25425083Sjdp movl $R(HIDENAME(tmpstk)),%esp 25515392Sphk 25624112Skato#ifdef PC98 25743447Skato /* pc98_machine_type & M_EPSON_PC98 */ 25843447Skato testb $0x02,R(_pc98_system_parameter)+220 25924112Skato jz 3f 26043447Skato /* epson_machine_id <= 0x0b */ 26143447Skato cmpb $0x0b,R(_pc98_system_parameter)+224 26224112Skato ja 3f 26324112Skato 26424112Skato /* count up memory */ 26524112Skato movl $0x100000,%eax /* next, talley remaining memory */ 26624112Skato movl $0xFFF-0x100,%ecx 26724112Skato1: movl 0(%eax),%ebx /* save location to check */ 26824112Skato movl $0xa55a5aa5,0(%eax) /* write test pattern */ 26924112Skato cmpl $0xa55a5aa5,0(%eax) /* does not check yet for rollover */ 27024112Skato jne 2f 27124112Skato movl %ebx,0(%eax) /* restore memory */ 27224112Skato addl $PAGE_SIZE,%eax 27324112Skato loop 1b 27424112Skato2: subl $0x100000,%eax 27524112Skato shrl $17,%eax 27643447Skato movb %al,R(_pc98_system_parameter)+1 27724112Skato3: 27858786Skato 27958786Skato movw R(_pc98_system_parameter+0x86),%ax 28058786Skato movw %ax,R(_cpu_id) 28124112Skato#endif 28224112Skato 28315392Sphk call identify_cpu 28415392Sphk 28515392Sphk/* clear bss */ 28615428Sphk/* 28717120Sbde * XXX this should be done a little earlier. 28815428Sphk * 28917120Sbde * XXX we don't check that there is memory for our bss and page tables 29017120Sbde * before using it. 29115428Sphk * 29215428Sphk * XXX the boot program somewhat bogusly clears the bss. We still have 29315428Sphk * to do it in case we were unzipped by kzipboot. Then the boot program 29415428Sphk * only clears kzipboot's bss. 29515428Sphk * 29615428Sphk * XXX the gdt and idt are still somewhere in the boot program. We 29715428Sphk * depend on the convention that the boot program is below 1MB and we 29815428Sphk * are above 1MB to keep the gdt and idt away from the bss and page 29917120Sbde * tables. The idt is only used if BDE_DEBUGGER is enabled. 30015428Sphk */ 30115392Sphk movl $R(_end),%ecx 30215392Sphk movl $R(_edata),%edi 30315392Sphk subl %edi,%ecx 30415392Sphk xorl %eax,%eax 30515428Sphk cld 30615428Sphk rep 30715428Sphk stosb 30815392Sphk 30915392Sphk call create_pagetables 31015392Sphk 31127993Sdyson/* 31227993Sdyson * If the CPU has support for VME, turn it on. 31327993Sdyson */ 31427993Sdyson testl $CPUID_VME, R(_cpu_feature) 31527993Sdyson jz 1f 31627993Sdyson movl %cr4, %eax 31727993Sdyson orl $CR4_VME, %eax 31827993Sdyson movl %eax, %cr4 31927993Sdyson1: 32027993Sdyson 32115428Sphk#ifdef BDE_DEBUGGER 32215428Sphk/* 32315428Sphk * Adjust as much as possible for paging before enabling paging so that the 32415428Sphk * adjustments can be traced. 32515428Sphk */ 32615428Sphk call bdb_prepare_paging 32715428Sphk#endif 32815428Sphk 32915392Sphk/* Now enable paging */ 33015392Sphk movl R(_IdlePTD), %eax 33115392Sphk movl %eax,%cr3 /* load ptd addr into mmu */ 33215392Sphk movl %cr0,%eax /* get control word */ 33315392Sphk orl $CR0_PE|CR0_PG,%eax /* enable paging */ 33415392Sphk movl %eax,%cr0 /* and let's page NOW! */ 33515392Sphk 33615428Sphk#ifdef BDE_DEBUGGER 33715428Sphk/* 33815428Sphk * Complete the adjustments for paging so that we can keep tracing through 33917120Sbde * initi386() after the low (physical) addresses for the gdt and idt become 34015428Sphk * invalid. 34115428Sphk */ 34215428Sphk call bdb_commit_paging 34315428Sphk#endif 34415428Sphk 34515428Sphk pushl $begin /* jump to high virtualized address */ 34615392Sphk ret 34715392Sphk 34815392Sphk/* now running relocated at KERNBASE where the system is linked to run */ 34915392Sphkbegin: 35015392Sphk /* set up bootstrap stack */ 35124691Speter movl _proc0paddr,%esp /* location of in-kernel pages */ 35224691Speter addl $UPAGES*PAGE_SIZE,%esp /* bootstrap stack end location */ 35315392Sphk xorl %eax,%eax /* mark end of frames */ 35415392Sphk movl %eax,%ebp 35515392Sphk movl _proc0paddr,%eax 35615392Sphk movl _IdlePTD, %esi 35715392Sphk movl %esi,PCB_CR3(%eax) 35815392Sphk 35915392Sphk movl physfree, %esi 36015392Sphk pushl %esi /* value of first for init386(first) */ 36115392Sphk call _init386 /* wire 386 chip for unix operation */ 36215392Sphk popl %esi 36315392Sphk 36415392Sphk .globl __ucodesel,__udatasel 36515392Sphk 36615392Sphk pushl $0 /* unused */ 36715392Sphk pushl __udatasel /* ss */ 36815392Sphk pushl $0 /* esp - filled in by execve() */ 36915392Sphk pushl $PSL_USER /* eflags (IOPL 0, int enab) */ 37015392Sphk pushl __ucodesel /* cs */ 37115392Sphk pushl $0 /* eip - filled in by execve() */ 37246129Sluoqi subl $(13*4),%esp /* space for rest of registers */ 37315392Sphk 37415392Sphk pushl %esp /* call main with frame pointer */ 37546823Speter call _mi_startup /* autoconfiguration, mountroot etc */ 37615392Sphk 37724691Speter hlt /* never returns to here */ 37815392Sphk 37924691Speter/* 38024691Speter * When starting init, call this to configure the process for user 38124691Speter * mode. This will be inherited by other processes. 38224691Speter */ 38324691SpeterNON_GPROF_ENTRY(prepare_usermode) 38415392Sphk /* 38524112Skato * Now we've run main() and determined what cpu-type we are, we can 38615392Sphk * enable write protection and alignment checking on i486 cpus and 38715392Sphk * above. 38815392Sphk */ 38915392Sphk#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) 39015392Sphk cmpl $CPUCLASS_386,_cpu_class 39115392Sphk je 1f 39215392Sphk movl %cr0,%eax /* get control word */ 39315392Sphk orl $CR0_WP|CR0_AM,%eax /* enable i486 features */ 39415392Sphk movl %eax,%cr0 /* and do it */ 39515428Sphk1: 39615392Sphk#endif 39715392Sphk /* 39815392Sphk * on return from main(), we are process 1 39915392Sphk * set up address space and stack so that we can 'return' to user mode 40015392Sphk */ 40115392Sphk movl __ucodesel,%eax 40215392Sphk movl __udatasel,%ecx 40315392Sphk 40446129Sluoqi#if 0 /* ds/es/fs are in trap frame */ 40560303Sobrien mov %cx,%ds 40660303Sobrien mov %cx,%es 40760303Sobrien mov %cx,%fs 40824691Speter#endif 40960303Sobrien mov %cx,%gs /* and ds to gs */ 41024691Speter ret /* goto user! */ 41115392Sphk 41224691Speter 41315392Sphk/* 41415392Sphk * Signal trampoline, copied to top of user stack 41515392Sphk */ 41615392SphkNON_GPROF_ENTRY(sigcode) 41760303Sobrien call *SIGF_HANDLER(%esp) /* call signal handler */ 41851984Smarcel lea SIGF_UC(%esp),%eax /* get ucontext_t */ 41915392Sphk pushl %eax 42052140Sluoqi testl $PSL_VM,UC_EFLAGS(%eax) 42152140Sluoqi jne 9f 42252140Sluoqi movl UC_GS(%eax),%gs /* restore %gs */ 42352140Sluoqi9: 42452140Sluoqi movl $SYS_sigreturn,%eax 42551792Smarcel pushl %eax /* junk to fake return addr. */ 42651792Smarcel int $0x80 /* enter kernel with args */ 42752140Sluoqi0: jmp 0b 42852140Sluoqi 42925083Sjdp ALIGN_TEXT 43052140Sluoqi_osigcode: 43160303Sobrien call *SIGF_HANDLER(%esp) /* call signal handler */ 43252140Sluoqi lea SIGF_SC(%esp),%eax /* get sigcontext */ 43352140Sluoqi pushl %eax 43452140Sluoqi testl $PSL_VM,SC_PS(%eax) 43552140Sluoqi jne 9f 43652140Sluoqi movl SC_GS(%eax),%gs /* restore %gs */ 43752140Sluoqi9: 43852140Sluoqi movl $0x01d516,SC_TRAPNO(%eax) /* magic: 0ldSiG */ 43952140Sluoqi movl $SYS_sigreturn,%eax 44052140Sluoqi pushl %eax /* junk to fake return addr. */ 44152140Sluoqi int $0x80 /* enter kernel with args */ 44252140Sluoqi0: jmp 0b 44352140Sluoqi 44452140Sluoqi ALIGN_TEXT 44515392Sphk_esigcode: 44615392Sphk 44715392Sphk .data 44854121Smarcel .globl _szsigcode, _szosigcode 44915392Sphk_szsigcode: 45015392Sphk .long _esigcode-_sigcode 45154121Smarcel_szosigcode: 45252140Sluoqi .long _esigcode-_osigcode 45315428Sphk .text 45415392Sphk 45515392Sphk/********************************************************************** 45615392Sphk * 45715392Sphk * Recover the bootinfo passed to us from the boot program 45815392Sphk * 45915392Sphk */ 46015392Sphkrecover_bootinfo: 46115392Sphk /* 4623284Srgrimes * This code is called in different ways depending on what loaded 4633284Srgrimes * and started the kernel. This is used to detect how we get the 4643284Srgrimes * arguments from the other code and what we do with them. 4653284Srgrimes * 4663284Srgrimes * Old disk boot blocks: 4673284Srgrimes * (*btext)(howto, bootdev, cyloffset, esym); 4683284Srgrimes * [return address == 0, and can NOT be returned to] 4693284Srgrimes * [cyloffset was not supported by the FreeBSD boot code 4703284Srgrimes * and always passed in as 0] 4713284Srgrimes * [esym is also known as total in the boot code, and 4723284Srgrimes * was never properly supported by the FreeBSD boot code] 4733284Srgrimes * 4743284Srgrimes * Old diskless netboot code: 4753284Srgrimes * (*btext)(0,0,0,0,&nfsdiskless,0,0,0); 4763284Srgrimes * [return address != 0, and can NOT be returned to] 4773284Srgrimes * If we are being booted by this code it will NOT work, 4783284Srgrimes * so we are just going to halt if we find this case. 4793284Srgrimes * 4803284Srgrimes * New uniform boot code: 4813284Srgrimes * (*btext)(howto, bootdev, 0, 0, 0, &bootinfo) 4823284Srgrimes * [return address != 0, and can be returned to] 4833284Srgrimes * 4843284Srgrimes * There may seem to be a lot of wasted arguments in here, but 4853384Srgrimes * that is so the newer boot code can still load very old kernels 4863384Srgrimes * and old boot code can load new kernels. 4874Srgrimes */ 4883284Srgrimes 4893284Srgrimes /* 4903284Srgrimes * The old style disk boot blocks fake a frame on the stack and 4913284Srgrimes * did an lret to get here. The frame on the stack has a return 4923284Srgrimes * address of 0. 4933284Srgrimes */ 4943384Srgrimes cmpl $0,4(%ebp) 49515392Sphk je olddiskboot 4963284Srgrimes 4973284Srgrimes /* 4983284Srgrimes * We have some form of return address, so this is either the 4993284Srgrimes * old diskless netboot code, or the new uniform code. That can 50015428Sphk * be detected by looking at the 5th argument, if it is 0 50115428Sphk * we are being booted by the new uniform boot code. 5023284Srgrimes */ 5033384Srgrimes cmpl $0,24(%ebp) 50415392Sphk je newboot 5053284Srgrimes 5063284Srgrimes /* 5073284Srgrimes * Seems we have been loaded by the old diskless boot code, we 5083284Srgrimes * don't stand a chance of running as the diskless structure 5093284Srgrimes * changed considerably between the two, so just halt. 5103284Srgrimes */ 5113284Srgrimes hlt 5123284Srgrimes 5133284Srgrimes /* 5143384Srgrimes * We have been loaded by the new uniform boot code. 51515428Sphk * Let's check the bootinfo version, and if we do not understand 5163384Srgrimes * it we return to the loader with a status of 1 to indicate this error 5173284Srgrimes */ 51815392Sphknewboot: 5193384Srgrimes movl 28(%ebp),%ebx /* &bootinfo.version */ 5205908Sbde movl BI_VERSION(%ebx),%eax 5213384Srgrimes cmpl $1,%eax /* We only understand version 1 */ 5223384Srgrimes je 1f 5233384Srgrimes movl $1,%eax /* Return status */ 5243384Srgrimes leave 52515428Sphk /* 52615428Sphk * XXX this returns to our caller's caller (as is required) since 52715428Sphk * we didn't set up a frame and our caller did. 52815428Sphk */ 5293384Srgrimes ret 5303284Srgrimes 5313384Srgrimes1: 5323284Srgrimes /* 5333384Srgrimes * If we have a kernelname copy it in 5343384Srgrimes */ 5355908Sbde movl BI_KERNELNAME(%ebx),%esi 5363384Srgrimes cmpl $0,%esi 5379344Sdg je 2f /* No kernelname */ 5389344Sdg movl $MAXPATHLEN,%ecx /* Brute force!!! */ 53915926Sphk movl $R(_kernelname),%edi 5409344Sdg cmpb $'/',(%esi) /* Make sure it starts with a slash */ 5419344Sdg je 1f 5429344Sdg movb $'/',(%edi) 5439344Sdg incl %edi 5449344Sdg decl %ecx 5459344Sdg1: 5463384Srgrimes cld 5473384Srgrimes rep 5483384Srgrimes movsb 5493384Srgrimes 5509344Sdg2: 55115428Sphk /* 5525908Sbde * Determine the size of the boot loader's copy of the bootinfo 5535908Sbde * struct. This is impossible to do properly because old versions 5545908Sbde * of the struct don't contain a size field and there are 2 old 5555908Sbde * versions with the same version number. 5564600Sphk */ 5575908Sbde movl $BI_ENDCOMMON,%ecx /* prepare for sizeless version */ 5585908Sbde testl $RB_BOOTINFO,8(%ebp) /* bi_size (and bootinfo) valid? */ 5595908Sbde je got_bi_size /* no, sizeless version */ 5605908Sbde movl BI_SIZE(%ebx),%ecx 5615908Sbdegot_bi_size: 5625908Sbde 56315428Sphk /* 5645908Sbde * Copy the common part of the bootinfo struct 5655908Sbde */ 5664600Sphk movl %ebx,%esi 56715926Sphk movl $R(_bootinfo),%edi 5685908Sbde cmpl $BOOTINFO_SIZE,%ecx 5695908Sbde jbe got_common_bi_size 5704600Sphk movl $BOOTINFO_SIZE,%ecx 5715908Sbdegot_common_bi_size: 5724600Sphk cld 5734600Sphk rep 5744600Sphk movsb 5754600Sphk 57638063Smsmith#ifdef NFS_ROOT 57725837Stegge#ifndef BOOTP_NFSV3 5783384Srgrimes /* 5793384Srgrimes * If we have a nfs_diskless structure copy it in 5803384Srgrimes */ 5815908Sbde movl BI_NFS_DISKLESS(%ebx),%esi 5823384Srgrimes cmpl $0,%esi 58315428Sphk je olddiskboot 58415926Sphk movl $R(_nfs_diskless),%edi 5853384Srgrimes movl $NFSDISKLESS_SIZE,%ecx 5863384Srgrimes cld 5873384Srgrimes rep 5883384Srgrimes movsb 58915926Sphk movl $R(_nfs_diskless_valid),%edi 5903795Sphk movl $1,(%edi) 5913406Sdg#endif 59225837Stegge#endif 5933384Srgrimes 5943384Srgrimes /* 5953284Srgrimes * The old style disk boot. 5963284Srgrimes * (*btext)(howto, bootdev, cyloffset, esym); 5973384Srgrimes * Note that the newer boot code just falls into here to pick 5983384Srgrimes * up howto and bootdev, cyloffset and esym are no longer used 5993284Srgrimes */ 60015392Sphkolddiskboot: 6013384Srgrimes movl 8(%ebp),%eax 60215926Sphk movl %eax,R(_boothowto) 6033384Srgrimes movl 12(%ebp),%eax 60415926Sphk movl %eax,R(_bootdev) 6052783Ssos 60615392Sphk ret 6073258Sdg 6081321Sdg 60915392Sphk/********************************************************************** 61015392Sphk * 61115392Sphk * Identify the CPU and initialize anything special about it 61215392Sphk * 61315392Sphk */ 61415392Sphkidentify_cpu: 61515392Sphk 6161998Swollman /* Try to toggle alignment check flag; does not exist on 386. */ 6171998Swollman pushfl 6181998Swollman popl %eax 6191998Swollman movl %eax,%ecx 6201998Swollman orl $PSL_AC,%eax 6211998Swollman pushl %eax 6221998Swollman popfl 6231998Swollman pushfl 6241998Swollman popl %eax 6251998Swollman xorl %ecx,%eax 6261998Swollman andl $PSL_AC,%eax 6271998Swollman pushl %ecx 6281998Swollman popfl 6291998Swollman 6301998Swollman testl %eax,%eax 63124112Skato jnz try486 63224112Skato 63324112Skato /* NexGen CPU does not have aligment check flag. */ 63424112Skato pushfl 63524112Skato movl $0x5555, %eax 63624112Skato xorl %edx, %edx 63724112Skato movl $2, %ecx 63824112Skato clc 63924112Skato divl %ecx 64024112Skato jz trynexgen 64124112Skato popfl 64215926Sphk movl $CPU_386,R(_cpu) 64313081Sdg jmp 3f 6441998Swollman 64524112Skatotrynexgen: 64627424Skato popfl 64724112Skato movl $CPU_NX586,R(_cpu) 64824112Skato movl $0x4778654e,R(_cpu_vendor) # store vendor string 64924112Skato movl $0x72446e65,R(_cpu_vendor+4) 65024112Skato movl $0x6e657669,R(_cpu_vendor+8) 65124112Skato movl $0,R(_cpu_vendor+12) 65224112Skato jmp 3f 65324112Skato 65424112Skatotry486: /* Try to toggle identification flag; does not exist on early 486s. */ 6551998Swollman pushfl 6561998Swollman popl %eax 6571998Swollman movl %eax,%ecx 6581998Swollman xorl $PSL_ID,%eax 6591998Swollman pushl %eax 6601998Swollman popfl 6611998Swollman pushfl 6621998Swollman popl %eax 6631998Swollman xorl %ecx,%eax 6641998Swollman andl $PSL_ID,%eax 6651998Swollman pushl %ecx 6661998Swollman popfl 6671998Swollman 6681998Swollman testl %eax,%eax 66924112Skato jnz trycpuid 67015926Sphk movl $CPU_486,R(_cpu) 6712495Spst 67224112Skato /* 67324112Skato * Check Cyrix CPU 67424112Skato * Cyrix CPUs do not change the undefined flags following 67524112Skato * execution of the divide instruction which divides 5 by 2. 67624112Skato * 67724112Skato * Note: CPUID is enabled on M2, so it passes another way. 67824112Skato */ 67924112Skato pushfl 68024112Skato movl $0x5555, %eax 68124112Skato xorl %edx, %edx 68224112Skato movl $2, %ecx 68324112Skato clc 68424112Skato divl %ecx 68524112Skato jnc trycyrix 68624112Skato popfl 68724112Skato jmp 3f /* You may use Intel CPU. */ 6882495Spst 68924112Skatotrycyrix: 69024112Skato popfl 69124112Skato /* 69224112Skato * IBM Bluelighting CPU also doesn't change the undefined flags. 69324112Skato * Because IBM doesn't disclose the information for Bluelighting 69424112Skato * CPU, we couldn't distinguish it from Cyrix's (including IBM 69524112Skato * brand of Cyrix CPUs). 69624112Skato */ 69715926Sphk movl $0x69727943,R(_cpu_vendor) # store vendor string 69824112Skato movl $0x736e4978,R(_cpu_vendor+4) 69924112Skato movl $0x64616574,R(_cpu_vendor+8) 70013014Sdg jmp 3f 7011998Swollman 70224112Skatotrycpuid: /* Use the `cpuid' instruction. */ 7031998Swollman xorl %eax,%eax 7046308Sphk .byte 0x0f,0xa2 # cpuid 0 70515926Sphk movl %eax,R(_cpu_high) # highest capability 70615926Sphk movl %ebx,R(_cpu_vendor) # store vendor string 70715926Sphk movl %edx,R(_cpu_vendor+4) 70815926Sphk movl %ecx,R(_cpu_vendor+8) 70915926Sphk movb $0,R(_cpu_vendor+12) 7101998Swollman 7111998Swollman movl $1,%eax 7126308Sphk .byte 0x0f,0xa2 # cpuid 1 71315926Sphk movl %eax,R(_cpu_id) # store cpu_id 71415926Sphk movl %edx,R(_cpu_feature) # store cpu_feature 7156308Sphk rorl $8,%eax # extract family type 7161998Swollman andl $15,%eax 7171998Swollman cmpl $5,%eax 7181998Swollman jae 1f 7191998Swollman 7201998Swollman /* less than Pentium; must be 486 */ 72115926Sphk movl $CPU_486,R(_cpu) 72213000Sdg jmp 3f 72313000Sdg1: 72413000Sdg /* a Pentium? */ 72513000Sdg cmpl $5,%eax 72613000Sdg jne 2f 72715926Sphk movl $CPU_586,R(_cpu) 72813000Sdg jmp 3f 729556Srgrimes2: 73013000Sdg /* Greater than Pentium...call it a Pentium Pro */ 73115926Sphk movl $CPU_686,R(_cpu) 73213000Sdg3: 73315392Sphk ret 734556Srgrimes 7354Srgrimes 73615392Sphk/********************************************************************** 737570Srgrimes * 73815428Sphk * Create the first page directory and its page tables. 73915392Sphk * 740570Srgrimes */ 741570Srgrimes 74215392Sphkcreate_pagetables: 74315392Sphk 74419621Sdyson testl $CPUID_PGE, R(_cpu_feature) 74519621Sdyson jz 1f 74619621Sdyson movl %cr4, %eax 74719621Sdyson orl $CR4_PGE, %eax 74819621Sdyson movl %eax, %cr4 74919621Sdyson1: 75019621Sdyson 75115428Sphk/* Find end of kernel image (rounded up to a page boundary). */ 75215392Sphk movl $R(_end),%esi 7534Srgrimes 75461422Sbde/* Include symbols, if any. */ 75515392Sphk movl R(_bootinfo+BI_ESYMTAB),%edi 7565908Sbde testl %edi,%edi 75715428Sphk je over_symalloc 7585908Sbde movl %edi,%esi 7595908Sbde movl $KERNBASE,%edi 76015392Sphk addl %edi,R(_bootinfo+BI_SYMTAB) 76115392Sphk addl %edi,R(_bootinfo+BI_ESYMTAB) 76215428Sphkover_symalloc: 7635908Sbde 76440081Smsmith/* If we are told where the end of the kernel space is, believe it. */ 76540081Smsmith movl R(_bootinfo+BI_KERNEND),%edi 76640081Smsmith testl %edi,%edi 76740081Smsmith je no_kernend 76840081Smsmith movl %edi,%esi 76940081Smsmithno_kernend: 77040081Smsmith 77115565Sphk addl $PAGE_MASK,%esi 77215565Sphk andl $~PAGE_MASK,%esi 77315392Sphk movl %esi,R(_KERNend) /* save end of kernel */ 77415428Sphk movl %esi,R(physfree) /* next free page is at end of kernel */ 775608Srgrimes 77615392Sphk/* Allocate Kernel Page Tables */ 77715392Sphk ALLOCPAGES(NKPT) 77815392Sphk movl %esi,R(_KPTphys) 779757Sdg 78015392Sphk/* Allocate Page Table Directory */ 78115392Sphk ALLOCPAGES(1) 78215392Sphk movl %esi,R(_IdlePTD) 7834Srgrimes 78415392Sphk/* Allocate UPAGES */ 78515392Sphk ALLOCPAGES(UPAGES) 78617120Sbde movl %esi,R(p0upa) 78715392Sphk addl $KERNBASE, %esi 78815392Sphk movl %esi, R(_proc0paddr) 7894Srgrimes 79037889Sjlemon ALLOCPAGES(1) /* vm86/bios stack */ 79137889Sjlemon movl %esi,R(vm86phystk) 79237889Sjlemon 79337889Sjlemon ALLOCPAGES(3) /* pgtable + ext + IOPAGES */ 79434840Sjlemon movl %esi,R(_vm86pa) 79534840Sjlemon addl $KERNBASE, %esi 79634840Sjlemon movl %esi, R(_vm86paddr) 79734840Sjlemon 79826812Speter#ifdef SMP 79925164Speter/* Allocate cpu0's private data page */ 80025164Speter ALLOCPAGES(1) 80125164Speter movl %esi,R(cpu0pp) 80225164Speter addl $KERNBASE, %esi 80325164Speter movl %esi, R(_cpu0prvpage) /* relocated to KVM space */ 80425164Speter 80546129Sluoqi/* Allocate SMP page table page */ 80625164Speter ALLOCPAGES(1) 80746129Sluoqi movl %esi,R(SMPptpa) 80825164Speter addl $KERNBASE, %esi 80946129Sluoqi movl %esi, R(_SMPpt) /* relocated to KVM space */ 81026812Speter#endif /* SMP */ 81125164Speter 81215392Sphk/* Map read-only from zero to the end of the kernel text section */ 81315565Sphk xorl %eax, %eax 81415428Sphk#ifdef BDE_DEBUGGER 81515428Sphk/* If the debugger is present, actually map everything read-write. */ 81615428Sphk cmpl $0,R(_bdb_exists) 81715428Sphk jne map_read_write 81815428Sphk#endif 81919621Sdyson xorl %edx,%edx 82027484Sdyson 82127484Sdyson#if !defined(SMP) 82219621Sdyson testl $CPUID_PGE, R(_cpu_feature) 82319621Sdyson jz 2f 82419621Sdyson orl $PG_G,%edx 82527484Sdyson#endif 82619621Sdyson 82719621Sdyson2: movl $R(_etext),%ecx 82815565Sphk addl $PAGE_MASK,%ecx 82915565Sphk shrl $PAGE_SHIFT,%ecx 83019621Sdyson fillkptphys(%edx) 831757Sdg 83215392Sphk/* Map read-write, data, bss and symbols */ 83315565Sphk movl $R(_etext),%eax 83415694Sphk addl $PAGE_MASK, %eax 83515694Sphk andl $~PAGE_MASK, %eax 83615428Sphkmap_read_write: 83719621Sdyson movl $PG_RW,%edx 83827484Sdyson#if !defined(SMP) 83919621Sdyson testl $CPUID_PGE, R(_cpu_feature) 84019621Sdyson jz 1f 84119621Sdyson orl $PG_G,%edx 84227484Sdyson#endif 84319621Sdyson 84419621Sdyson1: movl R(_KERNend),%ecx 845757Sdg subl %eax,%ecx 84615543Sphk shrl $PAGE_SHIFT,%ecx 84719621Sdyson fillkptphys(%edx) 848757Sdg 84915428Sphk/* Map page directory. */ 85015392Sphk movl R(_IdlePTD), %eax 85115392Sphk movl $1, %ecx 85219621Sdyson fillkptphys($PG_RW) 853757Sdg 85417120Sbde/* Map proc0's UPAGES in the physical way ... */ 85517120Sbde movl R(p0upa), %eax 85615392Sphk movl $UPAGES, %ecx 85719621Sdyson fillkptphys($PG_RW) 8584Srgrimes 85915565Sphk/* Map ISA hole */ 86015565Sphk movl $ISA_HOLE_START, %eax 86115565Sphk movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 86222130Sdg fillkptphys($PG_RW) 86315565Sphk 86434840Sjlemon/* Map space for the vm86 region */ 86537889Sjlemon movl R(vm86phystk), %eax 86634840Sjlemon movl $4, %ecx 86734840Sjlemon fillkptphys($PG_RW) 86834840Sjlemon 86934840Sjlemon/* Map page 0 into the vm86 page table */ 87034840Sjlemon movl $0, %eax 87134840Sjlemon movl $0, %ebx 87234840Sjlemon movl $1, %ecx 87334840Sjlemon fillkpt(R(_vm86pa), $PG_RW|PG_U) 87434840Sjlemon 87534840Sjlemon/* ...likewise for the ISA hole */ 87634840Sjlemon movl $ISA_HOLE_START, %eax 87734840Sjlemon movl $ISA_HOLE_START>>PAGE_SHIFT, %ebx 87834840Sjlemon movl $ISA_HOLE_LENGTH>>PAGE_SHIFT, %ecx 87934840Sjlemon fillkpt(R(_vm86pa), $PG_RW|PG_U) 88034840Sjlemon 88126812Speter#ifdef SMP 88226812Speter/* Map cpu0's private page into global kmem (4K @ cpu0prvpage) */ 88325164Speter movl R(cpu0pp), %eax 88425164Speter movl $1, %ecx 88525164Speter fillkptphys($PG_RW) 88625164Speter 88746129Sluoqi/* Map SMP page table page into global kmem FWIW */ 88846129Sluoqi movl R(SMPptpa), %eax 88925164Speter movl $1, %ecx 89025164Speter fillkptphys($PG_RW) 89125164Speter 89246129Sluoqi/* Map the private page into the SMP page table */ 89325164Speter movl R(cpu0pp), %eax 89425164Speter movl $0, %ebx /* pte offset = 0 */ 89525164Speter movl $1, %ecx /* one private page coming right up */ 89646129Sluoqi fillkpt(R(SMPptpa), $PG_RW) 89725164Speter 89826812Speter/* ... and put the page table table in the pde. */ 89946129Sluoqi movl R(SMPptpa), %eax 90025164Speter movl $MPPTDI, %ebx 90125164Speter movl $1, %ecx 90225164Speter fillkpt(R(_IdlePTD), $PG_RW) 90334840Sjlemon 90434840Sjlemon/* Fakeup VA for the local apic to allow early traps. */ 90534840Sjlemon ALLOCPAGES(1) 90634840Sjlemon movl %esi, %eax 90746129Sluoqi movl $(NPTEPG-1), %ebx /* pte offset = NTEPG-1 */ 90834840Sjlemon movl $1, %ecx /* one private pt coming right up */ 90946129Sluoqi fillkpt(R(SMPptpa), $PG_RW) 91034840Sjlemon 91134840Sjlemon/* Initialize mp lock to allow early traps */ 91234840Sjlemon movl $1, R(_mp_lock) 91326812Speter#endif /* SMP */ 91425164Speter 91515392Sphk/* install a pde for temporary double map of bottom of VA */ 91615392Sphk movl R(_KPTphys), %eax 91715565Sphk xorl %ebx, %ebx 91815565Sphk movl $1, %ecx 91919621Sdyson fillkpt(R(_IdlePTD), $PG_RW) 9204Srgrimes 92115392Sphk/* install pde's for pt's */ 92215392Sphk movl R(_KPTphys), %eax 92315565Sphk movl $KPTDI, %ebx 92415565Sphk movl $NKPT, %ecx 92519621Sdyson fillkpt(R(_IdlePTD), $PG_RW) 9264Srgrimes 92715392Sphk/* install a pde recursively mapping page directory as a page table */ 92815565Sphk movl R(_IdlePTD), %eax 92915565Sphk movl $PTDPTDI, %ebx 93015565Sphk movl $1,%ecx 93119621Sdyson fillkpt(R(_IdlePTD), $PG_RW) 9324Srgrimes 9334Srgrimes ret 93415428Sphk 93515428Sphk#ifdef BDE_DEBUGGER 93615428Sphkbdb_prepare_paging: 93715428Sphk cmpl $0,R(_bdb_exists) 93815428Sphk je bdb_prepare_paging_exit 93915428Sphk 94015428Sphk subl $6,%esp 94115428Sphk 94215428Sphk /* 94315428Sphk * Copy and convert debugger entries from the bootstrap gdt and idt 94415428Sphk * to the kernel gdt and idt. Everything is still in low memory. 94515428Sphk * Tracing continues to work after paging is enabled because the 94615428Sphk * low memory addresses remain valid until everything is relocated. 94715428Sphk * However, tracing through the setidt() that initializes the trace 94815428Sphk * trap will crash. 94915428Sphk */ 95015428Sphk sgdt (%esp) 95115428Sphk movl 2(%esp),%esi /* base address of bootstrap gdt */ 95215428Sphk movl $R(_gdt),%edi 95315428Sphk movl %edi,2(%esp) /* prepare to load kernel gdt */ 95415428Sphk movl $8*18/4,%ecx 95515428Sphk cld 95615428Sphk rep /* copy gdt */ 95715428Sphk movsl 95815428Sphk movl $R(_gdt),-8+2(%edi) /* adjust gdt self-ptr */ 95915428Sphk movb $0x92,-8+5(%edi) 96015428Sphk lgdt (%esp) 96115428Sphk 96215428Sphk sidt (%esp) 96315428Sphk movl 2(%esp),%esi /* base address of current idt */ 96415428Sphk movl 8+4(%esi),%eax /* convert dbg descriptor to ... */ 96515428Sphk movw 8(%esi),%ax 96615428Sphk movl %eax,R(bdb_dbg_ljmp+1) /* ... immediate offset ... */ 96715428Sphk movl 8+2(%esi),%eax 96815428Sphk movw %ax,R(bdb_dbg_ljmp+5) /* ... and selector for ljmp */ 96915428Sphk movl 24+4(%esi),%eax /* same for bpt descriptor */ 97015428Sphk movw 24(%esi),%ax 97115428Sphk movl %eax,R(bdb_bpt_ljmp+1) 97215428Sphk movl 24+2(%esi),%eax 97315428Sphk movw %ax,R(bdb_bpt_ljmp+5) 97448005Sbde movl R(_idt),%edi 97515428Sphk movl %edi,2(%esp) /* prepare to load kernel idt */ 97615428Sphk movl $8*4/4,%ecx 97715428Sphk cld 97815428Sphk rep /* copy idt */ 97915428Sphk movsl 98015428Sphk lidt (%esp) 98115428Sphk 98215428Sphk addl $6,%esp 98315428Sphk 98415428Sphkbdb_prepare_paging_exit: 98515428Sphk ret 98615428Sphk 98715428Sphk/* Relocate debugger gdt entries and gdt and idt pointers. */ 98815428Sphkbdb_commit_paging: 98915428Sphk cmpl $0,_bdb_exists 99015428Sphk je bdb_commit_paging_exit 99115428Sphk 99215428Sphk movl $_gdt+8*9,%eax /* adjust slots 9-17 */ 99315428Sphk movl $9,%ecx 99415428Sphkreloc_gdt: 99515428Sphk movb $KERNBASE>>24,7(%eax) /* top byte of base addresses, was 0, */ 99615428Sphk addl $8,%eax /* now KERNBASE>>24 */ 99715428Sphk loop reloc_gdt 99815428Sphk 99915428Sphk subl $6,%esp 100015428Sphk sgdt (%esp) 100115428Sphk addl $KERNBASE,2(%esp) 100215428Sphk lgdt (%esp) 100315428Sphk sidt (%esp) 100415428Sphk addl $KERNBASE,2(%esp) 100515428Sphk lidt (%esp) 100615428Sphk addl $6,%esp 100715428Sphk 100815428Sphk int $3 100915428Sphk 101015428Sphkbdb_commit_paging_exit: 101115428Sphk ret 101215428Sphk 101315428Sphk#endif /* BDE_DEBUGGER */ 1014