Annotation of src/sys/arch/i386/i386/locore.S, Revision 1.43
1.43 ! mrg 1: /* $NetBSD: locore.S,v 1.42 2006/07/08 20:30:00 christos Exp $ */
1.1 fvdl 2:
3: /*-
1.32 mycroft 4: * Copyright (c) 1998, 2000, 2004 The NetBSD Foundation, Inc.
1.1 fvdl 5: * All rights reserved.
6: *
7: * This code is derived from software contributed to The NetBSD Foundation
8: * by Charles M. Hannum.
9: *
10: * Redistribution and use in source and binary forms, with or without
11: * modification, are permitted provided that the following conditions
12: * are met:
13: * 1. Redistributions of source code must retain the above copyright
14: * notice, this list of conditions and the following disclaimer.
15: * 2. Redistributions in binary form must reproduce the above copyright
16: * notice, this list of conditions and the following disclaimer in the
17: * documentation and/or other materials provided with the distribution.
18: * 3. All advertising materials mentioning features or use of this software
19: * must display the following acknowledgement:
20: * This product includes software developed by the NetBSD
21: * Foundation, Inc. and its contributors.
22: * 4. Neither the name of The NetBSD Foundation nor the names of its
23: * contributors may be used to endorse or promote products derived
24: * from this software without specific prior written permission.
25: *
26: * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27: * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28: * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29: * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30: * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36: * POSSIBILITY OF SUCH DAMAGE.
37: */
38:
39: /*-
40: * Copyright (c) 1990 The Regents of the University of California.
41: * All rights reserved.
42: *
43: * This code is derived from software contributed to Berkeley by
44: * William Jolitz.
45: *
46: * Redistribution and use in source and binary forms, with or without
47: * modification, are permitted provided that the following conditions
48: * are met:
49: * 1. Redistributions of source code must retain the above copyright
50: * notice, this list of conditions and the following disclaimer.
51: * 2. Redistributions in binary form must reproduce the above copyright
52: * notice, this list of conditions and the following disclaimer in the
53: * documentation and/or other materials provided with the distribution.
1.12 agc 54: * 3. Neither the name of the University nor the names of its contributors
1.1 fvdl 55: * may be used to endorse or promote products derived from this software
56: * without specific prior written permission.
57: *
58: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68: * SUCH DAMAGE.
69: *
70: * @(#)locore.s 7.3 (Berkeley) 5/13/91
71: */
72:
1.18 christos 73: #include "opt_compat_netbsd.h"
74: #include "opt_compat_oldboot.h"
1.1 fvdl 75: #include "opt_cputype.h"
76: #include "opt_ddb.h"
77: #include "opt_ipkdb.h"
1.18 christos 78: #include "opt_lockdebug.h"
1.1 fvdl 79: #include "opt_multiprocessor.h"
80: #include "opt_realmem.h"
1.18 christos 81: #include "opt_user_ldt.h"
82: #include "opt_vm86.h"
1.1 fvdl 83:
84: #include "npx.h"
85: #include "assym.h"
86: #include "lapic.h"
87: #include "ioapic.h"
1.8 fvdl 88: #include "ksyms.h"
1.1 fvdl 89:
90: #include <sys/errno.h>
91: #include <sys/syscall.h>
92:
93: #include <machine/cputypes.h>
94: #include <machine/segments.h>
95: #include <machine/specialreg.h>
96: #include <machine/trap.h>
97:
98: #if NLAPIC > 0
99: #include <machine/i82489reg.h>
100: #endif
101:
1.37 jmmv 102: #include <machine/multiboot.h>
103:
1.1 fvdl 104: /* LINTSTUB: include <sys/types.h> */
105: /* LINTSTUB: include <machine/cpu.h> */
106: /* LINTSTUB: include <sys/systm.h> */
107:
108: #include <machine/asm.h>
109:
110: #if defined(MULTIPROCESSOR)
1.30 junyoung 111:
1.5 thorpej 112: #define SET_CURLWP(lwp,cpu) \
1.1 fvdl 113: movl CPUVAR(SELF),cpu ; \
1.5 thorpej 114: movl lwp,CPUVAR(CURLWP) ; \
115: movl cpu,L_CPU(lwp)
1.30 junyoung 116:
1.1 fvdl 117: #else
118:
1.5 thorpej 119: #define SET_CURLWP(lwp,tcpu) movl lwp,CPUVAR(CURLWP)
120: #define GET_CURLWP(reg) movl CPUVAR(CURLWP),reg
1.1 fvdl 121:
122: #endif
123:
124: #define SET_CURPCB(reg) movl reg,CPUVAR(CURPCB)
1.24 yamt 125:
1.1 fvdl 126: #define CLEAR_RESCHED(reg) movl reg,CPUVAR(RESCHED)
127:
128: /* XXX temporary kluge; these should not be here */
129: /* Get definitions for IOM_BEGIN, IOM_END, and IOM_SIZE */
130: #include <dev/isa/isareg.h>
131:
132:
133: /* Disallow old names for REALBASEMEM */
134: #ifdef BIOSBASEMEM
135: #error BIOSBASEMEM option deprecated; use REALBASEMEM only if memory size reported by latest boot block is incorrect
136: #endif
137:
138: /* Disallow old names for REALEXTMEM */
139: #ifdef EXTMEM_SIZE
140: #error EXTMEM_SIZE option deprecated; use REALEXTMEM only if memory size reported by latest boot block is incorrect
141: #endif
142: #ifdef BIOSEXTMEM
143: #error BIOSEXTMEM option deprecated; use REALEXTMEM only if memory size reported by latest boot block is incorrect
144: #endif
145:
146: #include <machine/frameasm.h>
147:
148:
149: #ifdef MULTIPROCESSOR
150: #include <machine/i82489reg.h>
151: #endif
1.30 junyoung 152:
1.1 fvdl 153: /*
154: * Initialization
155: */
156: .data
157:
158: .globl _C_LABEL(cpu)
1.38 jmmv 159: .globl _C_LABEL(esym)
160: .globl _C_LABEL(atdevbase)
1.40 yamt 161: .globl _C_LABEL(proc0uarea),_C_LABEL(PDPpaddr)
1.1 fvdl 162: .globl _C_LABEL(gdt)
163: #ifdef I586_CPU
164: .globl _C_LABEL(idt)
165: #endif
1.30 junyoung 166: .globl _C_LABEL(lapic_tpr)
167:
1.1 fvdl 168: #if NLAPIC > 0
169: #ifdef __ELF__
1.7 thorpej 170: .align PAGE_SIZE
1.1 fvdl 171: #else
172: .align 12
173: #endif
174: .globl _C_LABEL(local_apic), _C_LABEL(lapic_id)
175: _C_LABEL(local_apic):
176: .space LAPIC_ID
1.30 junyoung 177: _C_LABEL(lapic_id):
1.1 fvdl 178: .long 0x00000000
179: .space LAPIC_TPRI-(LAPIC_ID+4)
1.30 junyoung 180: _C_LABEL(lapic_tpr):
1.1 fvdl 181: .space LAPIC_PPRI-LAPIC_TPRI
1.30 junyoung 182: _C_LABEL(lapic_ppr):
1.1 fvdl 183: .space LAPIC_ISR-LAPIC_PPRI
184: _C_LABEL(lapic_isr):
1.7 thorpej 185: .space PAGE_SIZE-LAPIC_ISR
1.1 fvdl 186: #else
1.30 junyoung 187: _C_LABEL(lapic_tpr):
1.1 fvdl 188: .long 0
189: #endif
1.30 junyoung 190:
1.1 fvdl 191:
192: _C_LABEL(cpu): .long 0 # are we 386, 386sx, or 486,
193: # or Pentium, or..
194: _C_LABEL(atdevbase): .long 0 # location of start of iomem in virtual
1.40 yamt 195: _C_LABEL(proc0uarea): .long 0
1.31 junyoung 196: _C_LABEL(PDPpaddr): .long 0 # paddr of PDP, for libkvm
1.30 junyoung 197:
1.1 fvdl 198: .space 512
199: tmpstk:
200:
201:
1.35 yamt 202: #define _RELOC(x) ((x) - KERNBASE)
1.1 fvdl 203: #define RELOC(x) _RELOC(_C_LABEL(x))
204:
205: .text
206: .globl _C_LABEL(kernel_text)
207: .set _C_LABEL(kernel_text),KERNTEXTOFF
208:
209: .globl start
210: start: movw $0x1234,0x472 # warm boot
211:
1.37 jmmv 212: #if defined(MULTIBOOT)
213: jmp 1f
214:
215: .align 4
216: .globl Multiboot_Header
217: _C_LABEL(Multiboot_Header):
218: #define MULTIBOOT_HEADER_FLAGS (MULTIBOOT_HEADER_WANT_MEMORY | \
219: MULTIBOOT_HEADER_HAS_ADDR)
220: .long MULTIBOOT_HEADER_MAGIC
221: .long MULTIBOOT_HEADER_FLAGS
222: .long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
223: .long RELOC(Multiboot_Header)
224: .long RELOC(start)
225: .long RELOC(_edata)
226: .long RELOC(_end) + MULTIBOOT_SYMTAB_SPACE
227: .long RELOC(start)
228:
229: 1:
230: /* Check if we are being executed by a Multiboot-compliant boot
231: * loader. */
232: cmpl $MULTIBOOT_INFO_MAGIC,%eax
233: jne 1f
234:
1.43 ! mrg 235: /*
! 236: * Indeed, a multiboot-compliant boot loader executed us. We copy
1.37 jmmv 237: * the received Multiboot information structure into kernel's data
238: * space to process it later -- after we are relocated. It will
1.43 ! mrg 239: * be safer to run complex C code than doing it at this point.
! 240: */
1.37 jmmv 241: pushl %ebx # Address of Multiboot information
242: call _C_LABEL(multiboot_pre_reloc)
243: addl $4,%esp
1.38 jmmv 244: jmp 2f
1.37 jmmv 245: #endif
246:
247: 1:
1.1 fvdl 248: /*
1.38 jmmv 249: * At this point, we know that a NetBSD-specific boot loader
250: * booted this kernel. The stack carries the following parameters:
1.41 jmmv 251: * (boothowto, [bootdev], bootinfo, esym, biosextmem, biosbasemem),
1.38 jmmv 252: * 4 bytes each.
1.1 fvdl 253: */
1.38 jmmv 254: addl $4,%esp # Discard return address to boot loader
255: call _C_LABEL(native_loader)
256: addl $24,%esp
1.1 fvdl 257:
258: 2:
259: /* First, reset the PSL. */
260: pushl $PSL_MBO
261: popfl
262:
263: /* Clear segment registers; always null in proc0. */
264: xorl %eax,%eax
265: movw %ax,%fs
266: movw %ax,%gs
267: decl %eax
268: movl %eax,RELOC(cpu_info_primary)+CPU_INFO_LEVEL
269:
270: /* Find out our CPU type. */
271:
272: try386: /* Try to toggle alignment check flag; does not exist on 386. */
273: pushfl
274: popl %eax
275: movl %eax,%ecx
276: orl $PSL_AC,%eax
277: pushl %eax
278: popfl
279: pushfl
280: popl %eax
281: xorl %ecx,%eax
282: andl $PSL_AC,%eax
283: pushl %ecx
284: popfl
285:
286: testl %eax,%eax
287: jnz try486
288:
289: /*
290: * Try the test of a NexGen CPU -- ZF will not change on a DIV
291: * instruction on a NexGen, it will on an i386. Documented in
292: * Nx586 Processor Recognition Application Note, NexGen, Inc.
293: */
294: movl $0x5555,%eax
295: xorl %edx,%edx
296: movl $2,%ecx
297: divl %ecx
298: jnz is386
299:
300: isnx586:
301: /*
302: * Don't try cpuid, as Nx586s reportedly don't support the
303: * PSL_ID bit.
304: */
305: movl $CPU_NX586,RELOC(cpu)
306: jmp 2f
307:
308: is386:
309: movl $CPU_386,RELOC(cpu)
310: jmp 2f
311:
312: try486: /* Try to toggle identification flag; does not exist on early 486s. */
313: pushfl
314: popl %eax
315: movl %eax,%ecx
316: xorl $PSL_ID,%eax
317: pushl %eax
318: popfl
319: pushfl
320: popl %eax
321: xorl %ecx,%eax
322: andl $PSL_ID,%eax
323: pushl %ecx
324: popfl
325:
326: testl %eax,%eax
327: jnz try586
328: is486: movl $CPU_486,RELOC(cpu)
329: /*
330: * Check Cyrix CPU
331: * Cyrix CPUs do not change the undefined flags following
332: * execution of the divide instruction which divides 5 by 2.
333: *
334: * Note: CPUID is enabled on M2, so it passes another way.
335: */
336: pushfl
337: movl $0x5555, %eax
338: xorl %edx, %edx
339: movl $2, %ecx
340: clc
341: divl %ecx
342: jnc trycyrix486
343: popfl
344: jmp 2f
345: trycyrix486:
346: movl $CPU_6x86,RELOC(cpu) # set CPU type
347: /*
348: * Check for Cyrix 486 CPU by seeing if the flags change during a
349: * divide. This is documented in the Cx486SLC/e SMM Programmer's
350: * Guide.
351: */
352: xorl %edx,%edx
353: cmpl %edx,%edx # set flags to known state
354: pushfl
355: popl %ecx # store flags in ecx
356: movl $-1,%eax
357: movl $4,%ebx
358: divl %ebx # do a long division
359: pushfl
360: popl %eax
361: xorl %ecx,%eax # are the flags different?
362: testl $0x8d5,%eax # only check C|PF|AF|Z|N|V
363: jne 2f # yes; must be Cyrix 6x86 CPU
364: movl $CPU_486DLC,RELOC(cpu) # set CPU type
365:
366: #ifndef CYRIX_CACHE_WORKS
367: /* Disable caching of the ISA hole only. */
368: invd
369: movb $CCR0,%al # Configuration Register index (CCR0)
370: outb %al,$0x22
371: inb $0x23,%al
372: orb $(CCR0_NC1|CCR0_BARB),%al
373: movb %al,%ah
374: movb $CCR0,%al
375: outb %al,$0x22
376: movb %ah,%al
377: outb %al,$0x23
378: invd
379: #else /* CYRIX_CACHE_WORKS */
380: /* Set cache parameters */
381: invd # Start with guaranteed clean cache
382: movb $CCR0,%al # Configuration Register index (CCR0)
383: outb %al,$0x22
384: inb $0x23,%al
385: andb $~CCR0_NC0,%al
386: #ifndef CYRIX_CACHE_REALLY_WORKS
387: orb $(CCR0_NC1|CCR0_BARB),%al
388: #else
389: orb $CCR0_NC1,%al
390: #endif
391: movb %al,%ah
392: movb $CCR0,%al
393: outb %al,$0x22
394: movb %ah,%al
395: outb %al,$0x23
396: /* clear non-cacheable region 1 */
397: movb $(NCR1+2),%al
398: outb %al,$0x22
399: movb $NCR_SIZE_0K,%al
400: outb %al,$0x23
401: /* clear non-cacheable region 2 */
402: movb $(NCR2+2),%al
403: outb %al,$0x22
404: movb $NCR_SIZE_0K,%al
405: outb %al,$0x23
406: /* clear non-cacheable region 3 */
407: movb $(NCR3+2),%al
408: outb %al,$0x22
409: movb $NCR_SIZE_0K,%al
410: outb %al,$0x23
411: /* clear non-cacheable region 4 */
412: movb $(NCR4+2),%al
413: outb %al,$0x22
414: movb $NCR_SIZE_0K,%al
415: outb %al,$0x23
416: /* enable caching in CR0 */
417: movl %cr0,%eax
418: andl $~(CR0_CD|CR0_NW),%eax
419: movl %eax,%cr0
420: invd
421: #endif /* CYRIX_CACHE_WORKS */
422:
423: jmp 2f
424:
425: try586: /* Use the `cpuid' instruction. */
426: xorl %eax,%eax
427: cpuid
428: movl %eax,RELOC(cpu_info_primary)+CPU_INFO_LEVEL
429:
430: 2:
431: /*
432: * Finished with old stack; load new %esp now instead of later so we
433: * can trace this code without having to worry about the trace trap
434: * clobbering the memory test or the zeroing of the bss+bootstrap page
435: * tables.
436: *
437: * The boot program should check:
438: * text+data <= &stack_variable - more_space_for_stack
439: * text+data+bss+pad+space_for_page_tables <= end_of_memory
440: * Oops, the gdt is in the carcass of the boot program so clearing
441: * the rest of memory is still not possible.
442: */
443: movl $_RELOC(tmpstk),%esp # bootstrap stack end location
444:
445: /*
446: * Virtual address space of kernel:
447: *
1.30 junyoung 448: * text | data | bss | [syms] | page dir | proc0 kstack
1.1 fvdl 449: * 0 1 2 3
450: */
1.7 thorpej 451: #define PROC0PDIR ((0) * PAGE_SIZE)
452: #define PROC0STACK ((1) * PAGE_SIZE)
453: #define SYSMAP ((1+UPAGES) * PAGE_SIZE)
454: #define TABLESIZE ((1+UPAGES) * PAGE_SIZE) /* + nkpde * PAGE_SIZE */
1.1 fvdl 455:
456: /* Find end of kernel image. */
457: movl $RELOC(end),%edi
1.8 fvdl 458: #if (NKSYMS || defined(DDB) || defined(LKM)) && !defined(SYMTAB_SPACE)
1.1 fvdl 459: /* Save the symbols (if loaded). */
460: movl RELOC(esym),%eax
461: testl %eax,%eax
462: jz 1f
1.35 yamt 463: subl $KERNBASE,%eax
1.1 fvdl 464: movl %eax,%edi
465: 1:
466: #endif
467:
468: /* Calculate where to start the bootstrap tables. */
469: movl %edi,%esi # edi = esym ? esym : end
470: addl $PGOFSET,%esi # page align up
471: andl $~PGOFSET,%esi
472:
473: /*
474: * Calculate the size of the kernel page table directory, and
1.29 mycroft 475: * how many entries it will have. Adjust nkpde to the actual
476: * kernel size automatically. Account for the bootstrap tables,
477: * round up, and add an extra 4MB.
1.1 fvdl 478: */
1.29 mycroft 479: leal TABLESIZE+NBPD+PDOFSET(%edi),%eax
480: shrl $PDSHIFT,%eax
1.1 fvdl 481: movl RELOC(nkpde),%ecx # get nkpde
1.29 mycroft 482: cmpl %ecx,%eax
483: jb 1f
484: movl %eax,%ecx
485: 1: cmpl $NKPTP_MIN,%ecx # larger than min?
1.1 fvdl 486: jge 1f
487: movl $NKPTP_MIN,%ecx # set at min
488: jmp 2f
489: 1: cmpl $NKPTP_MAX,%ecx # larger than max?
490: jle 2f
491: movl $NKPTP_MAX,%ecx
1.29 mycroft 492: 2: movl %ecx,RELOC(nkpde)
1.1 fvdl 493:
494: /* Clear memory for bootstrap tables. */
495: shll $PGSHIFT,%ecx
496: addl $TABLESIZE,%ecx
497: addl %esi,%ecx # end of tables
498: subl %edi,%ecx # size of tables
499: shrl $2,%ecx
500: xorl %eax,%eax
501: cld
502: rep
503: stosl
504:
505: /*
506: * fillkpt
507: * eax = pte (page frame | control | status)
508: * ebx = page table address
509: * ecx = number of pages to map
510: */
511: #define fillkpt \
512: 1: movl %eax,(%ebx) ; \
1.7 thorpej 513: addl $PAGE_SIZE,%eax ; /* increment physical address */ \
1.1 fvdl 514: addl $4,%ebx ; /* next pte */ \
515: loop 1b ;
516:
517: /*
518: * Build initial page tables.
519: */
520: /* Calculate end of text segment, rounded to a page. */
521: leal (RELOC(etext)+PGOFSET),%edx
522: andl $~PGOFSET,%edx
1.30 junyoung 523:
1.1 fvdl 524: /* Skip over the first 1MB. */
525: movl $_RELOC(KERNTEXTOFF),%eax
526: movl %eax,%ecx
527: shrl $PGSHIFT,%ecx
528: leal (SYSMAP)(%esi,%ecx,4),%ebx
529:
530: /* Map the kernel text read-only. */
531: movl %edx,%ecx
532: subl %eax,%ecx
533: shrl $PGSHIFT,%ecx
534: orl $(PG_V|PG_KR),%eax
535: fillkpt
536:
537: /* Map the data, BSS, and bootstrap tables read-write. */
538: leal (PG_V|PG_KW)(%edx),%eax
539: movl RELOC(nkpde),%ecx
540: shll $PGSHIFT,%ecx
541: addl $TABLESIZE,%ecx
542: addl %esi,%ecx # end of tables
543: subl %edx,%ecx # subtract end of text
544: shrl $PGSHIFT,%ecx
545: fillkpt
546:
547: /* Map ISA I/O memory. */
548: movl $(IOM_BEGIN|PG_V|PG_KW/*|PG_N*/),%eax # having these bits set
549: movl $(IOM_SIZE>>PGSHIFT),%ecx # for this many pte s,
550: fillkpt
551:
552: /*
553: * Construct a page table directory.
554: */
555: /* Install PDEs for temporary double map of kernel. */
556: movl RELOC(nkpde),%ecx # for this many pde s,
557: leal (PROC0PDIR+0*4)(%esi),%ebx # which is where temp maps!
558: leal (SYSMAP+PG_V|PG_KW)(%esi),%eax # pte for KPT in proc 0,
559: fillkpt
560:
561: /* Map kernel PDEs. */
562: movl RELOC(nkpde),%ecx # for this many pde s,
563: leal (PROC0PDIR+PDSLOT_KERN*4)(%esi),%ebx # kernel pde offset
564: leal (SYSMAP+PG_V|PG_KW)(%esi),%eax # pte for KPT in proc 0,
565: fillkpt
566:
567: /* Install a PDE recursively mapping page directory as a page table! */
568: leal (PROC0PDIR+PG_V|PG_KW)(%esi),%eax # pte for ptd
569: movl %eax,(PROC0PDIR+PDSLOT_PTE*4)(%esi) # recursive PD slot
570:
1.31 junyoung 571: /* Save phys. addr of PDP, for libkvm. */
572: movl %esi,RELOC(PDPpaddr)
1.1 fvdl 573:
574: /* Load base of page directory and enable mapping. */
575: movl %esi,%eax # phys address of ptd in proc 0
576: movl %eax,%cr3 # load ptd addr into mmu
577: movl %cr0,%eax # get control word
578: # enable paging & NPX emulation
579: orl $(CR0_PE|CR0_PG|CR0_NE|CR0_TS|CR0_EM|CR0_MP),%eax
580: movl %eax,%cr0 # and let's page NOW!
581:
582: pushl $begin # jump to high mem
583: ret
584:
585: begin:
1.35 yamt 586: /* Now running relocated at KERNBASE. Remove double mapping. */
1.1 fvdl 587: movl _C_LABEL(nkpde),%ecx # for this many pde s,
588: leal (PROC0PDIR+0*4)(%esi),%ebx # which is where temp maps!
1.35 yamt 589: addl $(KERNBASE), %ebx # now use relocated address
1.1 fvdl 590: 1: movl $0,(%ebx)
591: addl $4,%ebx # next pde
592: loop 1b
593:
594: /* Relocate atdevbase. */
595: movl _C_LABEL(nkpde),%edx
596: shll $PGSHIFT,%edx
1.35 yamt 597: addl $(TABLESIZE+KERNBASE),%edx
1.1 fvdl 598: addl %esi,%edx
599: movl %edx,_C_LABEL(atdevbase)
600:
601: /* Set up bootstrap stack. */
1.35 yamt 602: leal (PROC0STACK+KERNBASE)(%esi),%eax
1.40 yamt 603: movl %eax,_C_LABEL(proc0uarea)
604: leal (KSTACK_SIZE-FRAMESIZE)(%eax),%esp
605: movl %esi,(KSTACK_SIZE+PCB_CR3)(%eax) # pcb->pcb_cr3
1.1 fvdl 606: xorl %ebp,%ebp # mark end of frames
607:
1.37 jmmv 608: #if defined(MULTIBOOT)
609: /* It is now safe to parse the Multiboot information structure
610: * we saved before from C code. Note that we cannot delay its
611: * parsing any more because initgdt (called below) needs to make
612: * use of this information. */
613: call _C_LABEL(multiboot_post_reloc)
614: #endif
615:
1.1 fvdl 616: subl $NGDT*8, %esp # space for temporary gdt
617: pushl %esp
618: call _C_LABEL(initgdt)
619: addl $4,%esp
1.30 junyoung 620:
1.1 fvdl 621: movl _C_LABEL(nkpde),%eax
622: shll $PGSHIFT,%eax
623: addl $TABLESIZE,%eax
624: addl %esi,%eax # skip past stack and page tables
625:
626: pushl %eax
627: call _C_LABEL(init386) # wire 386 chip for unix operation
628: addl $4+NGDT*8,%esp # pop temporary gdt
629:
630: #ifdef SAFARI_FIFO_HACK
631: movb $5,%al
632: movw $0x37b,%dx
633: outb %al,%dx
634: movw $0x37f,%dx
635: inb %dx,%al
636: movb %al,%cl
637:
638: orb $1,%cl
639:
640: movb $5,%al
641: movw $0x37b,%dx
642: outb %al,%dx
643: movw $0x37f,%dx
644: movb %cl,%al
645: outb %al,%dx
646: #endif /* SAFARI_FIFO_HACK */
647:
648: call _C_LABEL(main)
649:
650: /*
651: * void proc_trampoline(void);
652: * This is a trampoline function pushed onto the stack of a newly created
653: * process in order to do some additional setup. The trampoline is entered by
654: * cpu_switch()ing to the process, so we abuse the callee-saved registers used
655: * by cpu_switch() to store the information about the stub to call.
656: * NOTE: This function does not have a normal calling sequence!
657: */
658: /* LINTSTUB: Func: void proc_trampoline(void) */
659: NENTRY(proc_trampoline)
660: #ifdef MULTIPROCESSOR
661: call _C_LABEL(proc_trampoline_mp)
662: #endif
663: movl $IPL_NONE,CPUVAR(ILEVEL)
664: pushl %ebx
665: call *%esi
666: addl $4,%esp
1.24 yamt 667: DO_DEFERRED_SWITCH(%eax)
1.1 fvdl 668: INTRFASTEXIT
669: /* NOTREACHED */
670:
671: /*****************************************************************************/
1.16 christos 672: #ifdef COMPAT_16
1.1 fvdl 673: /*
674: * Signal trampoline; copied to top of user stack.
675: */
676: /* LINTSTUB: Var: char sigcode[1], esigcode[1]; */
677: NENTRY(sigcode)
678: /*
679: * Handler has returned here as if we called it. The sigcontext
680: * is on the stack after the 3 args "we" pushed.
681: */
682: leal 12(%esp),%eax # get pointer to sigcontext
683: movl %eax,4(%esp) # put it in the argument slot
684: # fake return address already there
1.17 christos 685: movl $SYS_compat_16___sigreturn14,%eax
1.1 fvdl 686: int $0x80 # enter kernel with args on stack
687: movl $SYS_exit,%eax
688: int $0x80 # exit if sigreturn fails
689: .globl _C_LABEL(esigcode)
690: _C_LABEL(esigcode):
1.16 christos 691: #endif
1.1 fvdl 692:
693: /*****************************************************************************/
694:
695: /*
696: * The following is i386-specific nonsense.
697: */
698:
699: /*
700: * void lgdt(struct region_descriptor *rdp);
701: * Load a new GDT pointer (and do any necessary cleanup).
702: * XXX It's somewhat questionable whether reloading all the segment registers
703: * is necessary, since the actual descriptor data is not changed except by
704: * process creation and exit, both of which clean up via task switches. OTOH,
705: * this only happens at run time when the GDT is resized.
706: */
707: /* LINTSTUB: Func: void lgdt(struct region_descriptor *rdp) */
708: NENTRY(lgdt)
709: /* Reload the descriptor table. */
710: movl 4(%esp),%eax
711: lgdt (%eax)
712: /* Flush the prefetch queue. */
713: jmp 1f
714: nop
715: 1: /* Reload "stale" selectors. */
716: movl $GSEL(GDATA_SEL, SEL_KPL),%eax
717: movw %ax,%ds
718: movw %ax,%es
719: movw %ax,%gs
720: movw %ax,%ss
721: movl $GSEL(GCPU_SEL, SEL_KPL),%eax
722: movw %ax,%fs
723: /* Reload code selector by doing intersegment return. */
724: popl %eax
725: pushl $GSEL(GCODE_SEL, SEL_KPL)
726: pushl %eax
727: lret
728:
729: /*****************************************************************************/
730:
731: /*
732: * These functions are primarily used by DDB.
733: */
734:
735: /* LINTSTUB: Func: int setjmp (label_t *l) */
736: ENTRY(setjmp)
737: movl 4(%esp),%eax
738: movl %ebx,(%eax) # save ebx
739: movl %esp,4(%eax) # save esp
740: movl %ebp,8(%eax) # save ebp
741: movl %esi,12(%eax) # save esi
742: movl %edi,16(%eax) # save edi
743: movl (%esp),%edx # get rta
744: movl %edx,20(%eax) # save eip
745: xorl %eax,%eax # return (0);
746: ret
747:
748: /* LINTSTUB: Func: void longjmp (label_t *l) */
749: ENTRY(longjmp)
750: movl 4(%esp),%eax
751: movl (%eax),%ebx # restore ebx
752: movl 4(%eax),%esp # restore esp
753: movl 8(%eax),%ebp # restore ebp
754: movl 12(%eax),%esi # restore esi
755: movl 16(%eax),%edi # restore edi
756: movl 20(%eax),%edx # get rta
757: movl %edx,(%esp) # put in return frame
758: xorl %eax,%eax # return (1);
759: incl %eax
760: ret
761:
762: /*****************************************************************************/
763:
764: .globl _C_LABEL(sched_whichqs),_C_LABEL(sched_qs)
765: .globl _C_LABEL(uvmexp),_C_LABEL(panic)
766:
767: #ifdef DIAGNOSTIC
768: NENTRY(switch_error)
769: pushl $1f
770: call _C_LABEL(panic)
771: /* NOTREACHED */
772: 1: .asciz "cpu_switch"
773: #endif /* DIAGNOSTIC */
774:
775: /*
1.5 thorpej 776: * void cpu_switch(struct lwp *)
1.39 skrll 777: * Find a runnable lwp and switch to it. Wait if necessary. If the new
778: * lwp is the same as the old one, we short-circuit the context save and
1.1 fvdl 779: * restore.
1.30 junyoung 780: *
1.1 fvdl 781: * Note that the stack frame layout is known to "struct switchframe"
1.30 junyoung 782: * in <machine/frame.h> and to the code in cpu_fork() which initializes
1.5 thorpej 783: * it for a new lwp.
1.1 fvdl 784: */
785: ENTRY(cpu_switch)
786: pushl %ebx
787: pushl %esi
788: pushl %edi
789:
790: #ifdef DEBUG
791: cmpl $IPL_SCHED,CPUVAR(ILEVEL)
792: jae 1f
1.5 thorpej 793: pushl $2f
1.1 fvdl 794: call _C_LABEL(panic)
795: /* NOTREACHED */
1.5 thorpej 796: 2: .asciz "not splsched() in cpu_switch!"
1.30 junyoung 797: 1:
1.1 fvdl 798: #endif /* DEBUG */
1.30 junyoung 799:
1.5 thorpej 800: movl 16(%esp),%esi # current
1.1 fvdl 801:
802: /*
1.5 thorpej 803: * Clear curlwp so that we don't accumulate system time while idle.
804: * This also insures that schedcpu() will move the old lwp to
1.1 fvdl 805: * the correct queue if it happens to get called from the spllower()
806: * below and changes the priority. (See corresponding comment in
807: * userret()).
808: */
1.5 thorpej 809: movl $0,CPUVAR(CURLWP)
1.1 fvdl 810: /*
1.5 thorpej 811: * First phase: find new lwp.
1.1 fvdl 812: *
813: * Registers:
814: * %eax - queue head, scratch, then zero
815: * %ebx - queue number
816: * %ecx - cached value of whichqs
1.5 thorpej 817: * %edx - next lwp in queue
818: * %esi - old lwp
819: * %edi - new lwp
1.1 fvdl 820: */
821:
1.5 thorpej 822: /* Look for new lwp. */
1.1 fvdl 823: cli # splhigh doesn't do a cli
824: movl _C_LABEL(sched_whichqs),%ecx
825: bsfl %ecx,%ebx # find a full q
826: jnz switch_dequeue
827:
828: /*
829: * idling: save old context.
830: *
831: * Registers:
832: * %eax, %ecx - scratch
1.5 thorpej 833: * %esi - old lwp, then old pcb
1.1 fvdl 834: * %edi - idle pcb
835: */
836:
837: pushl %esi
1.24 yamt 838: call _C_LABEL(pmap_deactivate2) # pmap_deactivate(oldproc)
1.1 fvdl 839: addl $4,%esp
840:
1.5 thorpej 841: movl L_ADDR(%esi),%esi
1.1 fvdl 842:
843: /* Save stack pointers. */
844: movl %esp,PCB_ESP(%esi)
845: movl %ebp,PCB_EBP(%esi)
846:
847: /* Find idle PCB for this CPU */
848: #ifndef MULTIPROCESSOR
1.5 thorpej 849: movl $_C_LABEL(lwp0),%ebx
850: movl L_ADDR(%ebx),%edi
851: movl L_MD_TSS_SEL(%ebx),%edx
1.1 fvdl 852: #else
853: movl CPUVAR(IDLE_PCB),%edi
854: movl CPUVAR(IDLE_TSS_SEL),%edx
855: #endif
1.5 thorpej 856: movl $0,CPUVAR(CURLWP) /* In case we fault... */
1.1 fvdl 857:
858: /* Restore the idle context (avoid interrupts) */
859: cli
860:
861: /* Restore stack pointers. */
862: movl PCB_ESP(%edi),%esp
863: movl PCB_EBP(%edi),%ebp
864:
865: /* Switch TSS. Reset "task busy" flag before loading. */
1.26 yamt 866: movl %cr3,%eax
867: movl %eax,PCB_CR3(%edi)
1.1 fvdl 868: #ifdef MULTIPROCESSOR
869: movl CPUVAR(GDT),%eax
870: #else
871: movl _C_LABEL(gdt),%eax
872: #endif
873: andl $~0x0200,4-SEL_KPL(%eax,%edx,1)
874: ltr %dx
875:
876: /* We're always in the kernel, so we don't need the LDT. */
877:
878: /* Restore cr0 (including FPU state). */
879: movl PCB_CR0(%edi),%ecx
880: movl %ecx,%cr0
881:
882: /* Record new pcb. */
883: SET_CURPCB(%edi)
884:
885: xorl %esi,%esi
886: sti
1.30 junyoung 887: idle_unlock:
888: #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG)
1.1 fvdl 889: call _C_LABEL(sched_unlock_idle)
890: #endif
891: /* Interrupts are okay again. */
1.2 fvdl 892: pushl $IPL_NONE # spl0()
1.1 fvdl 893: call _C_LABEL(Xspllower) # process pending interrupts
1.2 fvdl 894: addl $4,%esp
1.1 fvdl 895: jmp idle_start
1.30 junyoung 896: idle_zero:
1.1 fvdl 897: sti
898: call _C_LABEL(uvm_pageidlezero)
899: cli
900: cmpl $0,_C_LABEL(sched_whichqs)
901: jnz idle_exit
902: idle_loop:
903: /* Try to zero some pages. */
904: movl _C_LABEL(uvm)+UVM_PAGE_IDLE_ZERO,%ecx
905: testl %ecx,%ecx
906: jnz idle_zero
907: sti
908: hlt
909: NENTRY(mpidle)
1.30 junyoung 910: idle_start:
1.1 fvdl 911: cli
912: cmpl $0,_C_LABEL(sched_whichqs)
913: jz idle_loop
1.30 junyoung 914: idle_exit:
1.1 fvdl 915: movl $IPL_HIGH,CPUVAR(ILEVEL) # splhigh
1.14 fvdl 916: sti
1.30 junyoung 917: #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG)
1.1 fvdl 918: call _C_LABEL(sched_lock_idle)
919: #endif
920: movl _C_LABEL(sched_whichqs),%ecx
921: bsfl %ecx,%ebx
922: jz idle_unlock
923:
1.30 junyoung 924: switch_dequeue:
925: /*
1.1 fvdl 926: * we're running at splhigh(), but it's otherwise okay to take
1.30 junyoung 927: * interrupts here.
1.1 fvdl 928: */
929: sti
930: leal _C_LABEL(sched_qs)(,%ebx,8),%eax # select q
931:
1.5 thorpej 932: movl L_FORW(%eax),%edi # unlink from front of process q
1.1 fvdl 933: #ifdef DIAGNOSTIC
934: cmpl %edi,%eax # linked to self (i.e. nothing queued)?
935: je _C_LABEL(switch_error) # not possible
936: #endif /* DIAGNOSTIC */
1.5 thorpej 937: movl L_FORW(%edi),%edx
938: movl %edx,L_FORW(%eax)
939: movl %eax,L_BACK(%edx)
1.1 fvdl 940:
941: cmpl %edx,%eax # q empty?
942: jne 3f
943:
944: btrl %ebx,%ecx # yes, clear to indicate empty
945: movl %ecx,_C_LABEL(sched_whichqs) # update q status
946:
947: 3: /* We just did it. */
948: xorl %eax,%eax
949: CLEAR_RESCHED(%eax)
950:
1.5 thorpej 951: switch_resume:
1.1 fvdl 952: #ifdef DIAGNOSTIC
1.5 thorpej 953: cmpl %eax,L_WCHAN(%edi) # Waiting for something?
1.1 fvdl 954: jne _C_LABEL(switch_error) # Yes; shouldn't be queued.
1.5 thorpej 955: cmpb $LSRUN,L_STAT(%edi) # In run state?
1.1 fvdl 956: jne _C_LABEL(switch_error) # No; shouldn't be queued.
957: #endif /* DIAGNOSTIC */
958:
1.5 thorpej 959: /* Isolate lwp. XXX Is this necessary? */
960: movl %eax,L_BACK(%edi)
1.1 fvdl 961:
1.5 thorpej 962: /* Record new lwp. */
963: movb $LSONPROC,L_STAT(%edi) # l->l_stat = LSONPROC
964: SET_CURLWP(%edi,%ecx)
1.1 fvdl 965:
1.5 thorpej 966: /* Skip context switch if same lwp. */
1.10 fvdl 967: xorl %ebx,%ebx
1.1 fvdl 968: cmpl %edi,%esi
969: je switch_return
970:
1.5 thorpej 971: /* If old lwp exited, don't bother. */
1.1 fvdl 972: testl %esi,%esi
973: jz switch_exited
974:
975: /*
976: * Second phase: save old context.
977: *
978: * Registers:
979: * %eax, %ecx - scratch
1.5 thorpej 980: * %esi - old lwp, then old pcb
981: * %edi - new lwp
1.1 fvdl 982: */
983:
984: pushl %esi
1.24 yamt 985: call _C_LABEL(pmap_deactivate2) # pmap_deactivate(oldproc)
1.1 fvdl 986: addl $4,%esp
987:
1.5 thorpej 988: movl L_ADDR(%esi),%esi
1.1 fvdl 989:
990: /* Save stack pointers. */
991: movl %esp,PCB_ESP(%esi)
992: movl %ebp,PCB_EBP(%esi)
993:
994: switch_exited:
995: /*
996: * Third phase: restore saved context.
997: *
998: * Registers:
999: * %eax, %ebx, %ecx, %edx - scratch
1000: * %esi - new pcb
1.5 thorpej 1001: * %edi - new lwp
1.1 fvdl 1002: */
1003:
1004: /* No interrupts while loading new state. */
1005: cli
1.5 thorpej 1006: movl L_ADDR(%edi),%esi
1.1 fvdl 1007:
1008: /* Restore stack pointers. */
1009: movl PCB_ESP(%esi),%esp
1010: movl PCB_EBP(%esi),%ebp
1011:
1012: #if 0
1013: /* Don't bother with the rest if switching to a system process. */
1.5 thorpej 1014: testl $P_SYSTEM,L_FLAG(%edi); XXX NJWLWP lwp's don't have P_SYSTEM!
1.1 fvdl 1015: jnz switch_restored
1016: #endif
1017:
1.26 yamt 1018: /* Switch TSS. Reset "task busy" flag before loading. */
1019: movl %cr3,%eax
1020: movl %eax,PCB_CR3(%esi) /* XXX should be done by pmap_activate? */
1.1 fvdl 1021: #ifdef MULTIPROCESSOR
1022: movl CPUVAR(GDT),%eax
1.30 junyoung 1023: #else
1.1 fvdl 1024: /* Load TSS info. */
1025: movl _C_LABEL(gdt),%eax
1026: #endif
1.5 thorpej 1027: movl L_MD_TSS_SEL(%edi),%edx
1.1 fvdl 1028:
1029: andl $~0x0200,4(%eax,%edx, 1)
1030: ltr %dx
1031:
1032: pushl %edi
1033: call _C_LABEL(pmap_activate) # pmap_activate(p)
1034: addl $4,%esp
1035:
1036: #if 0
1037: switch_restored:
1038: #endif
1039: /* Restore cr0 (including FPU state). */
1040: movl PCB_CR0(%esi),%ecx
1041: #ifdef MULTIPROCESSOR
1.30 junyoung 1042: /*
1.22 wiz 1043: * If our floating point registers are on a different CPU,
1.1 fvdl 1044: * clear CR0_TS so we'll trap rather than reuse bogus state.
1045: */
1046: movl PCB_FPCPU(%esi),%ebx
1047: cmpl CPUVAR(SELF),%ebx
1048: jz 1f
1049: orl $CR0_TS,%ecx
1.30 junyoung 1050: 1:
1051: #endif
1.1 fvdl 1052: movl %ecx,%cr0
1053:
1054: /* Record new pcb. */
1055: SET_CURPCB(%esi)
1056:
1057: /* Interrupts are okay again. */
1058: sti
1059:
1060: /*
1061: * Check for restartable atomic sequences (RAS)
1062: */
1.5 thorpej 1063: movl CPUVAR(CURLWP),%edi
1064: movl L_PROC(%edi),%esi
1.20 dsl 1065: cmpl $0,P_RASLIST(%esi)
1066: jne 2f
1.1 fvdl 1067: 1:
1.10 fvdl 1068: movl $1,%ebx
1.1 fvdl 1069:
1070: switch_return:
1.30 junyoung 1071: #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG)
1.1 fvdl 1072: call _C_LABEL(sched_unlock_idle)
1073: #endif
1.28 yamt 1074: cmpl $0,CPUVAR(IPENDING)
1075: jz 3f
1.2 fvdl 1076: pushl $IPL_NONE # spl0()
1.1 fvdl 1077: call _C_LABEL(Xspllower) # process pending interrupts
1.2 fvdl 1078: addl $4,%esp
1.28 yamt 1079: 3:
1.1 fvdl 1080: movl $IPL_HIGH,CPUVAR(ILEVEL) # splhigh()
1.9 fvdl 1081:
1082: movl %ebx,%eax
1.30 junyoung 1083:
1.1 fvdl 1084: popl %edi
1085: popl %esi
1086: popl %ebx
1087: ret
1.20 dsl 1088:
1089: 2: # check RAS list
1090: movl L_MD_REGS(%edi),%ebx
1091: movl TF_EIP(%ebx),%eax
1092: pushl %eax
1093: pushl %esi
1094: call _C_LABEL(ras_lookup)
1095: addl $8,%esp
1096: cmpl $-1,%eax
1097: je 1b
1098: movl %eax,TF_EIP(%ebx)
1099: jmp 1b
1.1 fvdl 1100:
1101: /*
1.5 thorpej 1102: * void cpu_switchto(struct lwp *current, struct lwp *next)
1103: * Switch to the specified next LWP.
1104: */
1105: ENTRY(cpu_switchto)
1106: pushl %ebx
1107: pushl %esi
1108: pushl %edi
1109:
1110: #ifdef DEBUG
1111: cmpl $IPL_SCHED,CPUVAR(ILEVEL)
1112: jae 1f
1113: pushl $2f
1114: call _C_LABEL(panic)
1115: /* NOTREACHED */
1116: 2: .asciz "not splsched() in cpu_switchto!"
1117: 1:
1118: #endif /* DEBUG */
1119:
1120: movl 16(%esp),%esi # current
1121: movl 20(%esp),%edi # next
1122:
1123: /*
1124: * Clear curlwp so that we don't accumulate system time while idle.
1125: * This also insures that schedcpu() will move the old process to
1126: * the correct queue if it happens to get called from the spllower()
1127: * below and changes the priority. (See corresponding comment in
1128: * usrret()).
1129: *
1130: * XXX Is this necessary? We know we won't go idle.
1131: */
1132: movl $0,CPUVAR(CURLWP)
1133:
1134: /*
1135: * We're running at splhigh(), but it's otherwise okay to take
1136: * interrupts here.
1137: */
1138: sti
1139:
1140: /* Jump into the middle of cpu_switch */
1141: xorl %eax,%eax
1142: jmp switch_resume
1143:
1144: /*
1.21 jdolecek 1145: * void cpu_exit(struct lwp *l)
1.30 junyoung 1146: * Switch to the appropriate idle context (lwp0's if uniprocessor; the CPU's
1147: * if multiprocessor) and deallocate the address space and kernel stack for p.
1.1 fvdl 1148: * Then jump into cpu_switch(), as if we were in the idle proc all along.
1149: */
1150: #ifndef MULTIPROCESSOR
1.5 thorpej 1151: .globl _C_LABEL(lwp0)
1.1 fvdl 1152: #endif
1.21 jdolecek 1153: /* LINTSTUB: Func: void cpu_exit(struct lwp *l) */
1154: ENTRY(cpu_exit)
1.1 fvdl 1155: movl 4(%esp),%edi # old process
1156: #ifndef MULTIPROCESSOR
1.5 thorpej 1157: movl $_C_LABEL(lwp0),%ebx
1158: movl L_ADDR(%ebx),%esi
1159: movl L_MD_TSS_SEL(%ebx),%edx
1.1 fvdl 1160: #else
1161: movl CPUVAR(IDLE_PCB),%esi
1162: movl CPUVAR(IDLE_TSS_SEL),%edx
1163: #endif
1164: /* In case we fault... */
1.5 thorpej 1165: movl $0,CPUVAR(CURLWP)
1.1 fvdl 1166:
1167: /* Restore the idle context. */
1168: cli
1169:
1170: /* Restore stack pointers. */
1171: movl PCB_ESP(%esi),%esp
1172: movl PCB_EBP(%esi),%ebp
1173:
1.26 yamt 1174: /* Switch TSS. Reset "task busy" flag before loading. */
1175: movl %cr3,%eax
1176: movl %eax,PCB_CR3(%esi)
1.1 fvdl 1177: #ifdef MULTIPROCESSOR
1178: movl CPUVAR(GDT),%eax
1.30 junyoung 1179: #else
1.1 fvdl 1180: /* Load TSS info. */
1181: movl _C_LABEL(gdt),%eax
1182: #endif
1183:
1184: andl $~0x0200,4-SEL_KPL(%eax,%edx,1)
1185: ltr %dx
1186:
1187: /* We're always in the kernel, so we don't need the LDT. */
1188:
1189: /* Restore cr0 (including FPU state). */
1190: movl PCB_CR0(%esi),%ecx
1191: movl %ecx,%cr0
1192:
1193: /* Record new pcb. */
1194: SET_CURPCB(%esi)
1195:
1196: /* Interrupts are okay again. */
1197: sti
1198:
1199: /*
1.21 jdolecek 1200: * Schedule the dead LWP's stack to be freed.
1.1 fvdl 1201: */
1.21 jdolecek 1202: pushl %edi
1203: call _C_LABEL(lwp_exit2)
1.1 fvdl 1204: addl $4,%esp
1205:
1206: /* Jump into cpu_switch() with the right state. */
1207: xorl %esi,%esi
1.5 thorpej 1208: movl %esi,CPUVAR(CURLWP)
1.1 fvdl 1209: jmp idle_start
1210:
1211: /*
1212: * void savectx(struct pcb *pcb);
1213: * Update pcb, saving current processor state.
1214: */
1215: /* LINTSTUB: Func: void savectx(struct pcb *pcb) */
1216: ENTRY(savectx)
1217: movl 4(%esp),%edx # edx = p->p_addr
1.30 junyoung 1218:
1.1 fvdl 1219: /* Save stack pointers. */
1220: movl %esp,PCB_ESP(%edx)
1221: movl %ebp,PCB_EBP(%edx)
1222:
1223: ret
1224:
1225: /*
1226: * Old call gate entry for syscall
1227: */
1228: /* LINTSTUB: Var: char Xosyscall[1]; */
1229: IDTVEC(osyscall)
1230: /* Set eflags in trap frame. */
1231: pushfl
1232: popl 8(%esp)
1233: pushl $7 # size of instruction for restart
1234: jmp syscall1
1235:
1236: /*
1237: * Trap gate entry for syscall
1238: */
1239: /* LINTSTUB: Var: char Xsyscall[1]; */
1240: IDTVEC(syscall)
1241: pushl $2 # size of instruction for restart
1242: syscall1:
1243: pushl $T_ASTFLT # trap # for doing ASTs
1244: INTRENTRY
1245:
1246: #ifdef DIAGNOSTIC
1.24 yamt 1247: cmpl $0, CPUVAR(WANT_PMAPLOAD)
1248: jz 1f
1249: pushl $6f
1250: call _C_LABEL(printf)
1251: addl $4, %esp
1252: 1:
1.1 fvdl 1253: movl CPUVAR(ILEVEL),%ebx
1254: testl %ebx,%ebx
1255: jz 1f
1256: pushl $5f
1257: call _C_LABEL(printf)
1258: addl $4,%esp
1259: #ifdef DDB
1260: int $3
1261: #endif
1.30 junyoung 1262: 1:
1.1 fvdl 1263: #endif /* DIAGNOSTIC */
1.5 thorpej 1264: movl CPUVAR(CURLWP),%edx
1265: movl %esp,L_MD_REGS(%edx) # save pointer to frame
1266: movl L_PROC(%edx),%edx
1.15 fvdl 1267: pushl %esp
1.1 fvdl 1268: call *P_MD_SYSCALL(%edx) # get pointer to syscall() function
1.15 fvdl 1269: addl $4,%esp
1.27 yamt 1270: .Lsyscall_checkast:
1.24 yamt 1271: /* Check for ASTs on exit to user mode. */
1.1 fvdl 1272: cli
1.5 thorpej 1273: CHECK_ASTPENDING(%eax)
1.1 fvdl 1274: je 1f
1275: /* Always returning to user mode here. */
1.5 thorpej 1276: CLEAR_ASTPENDING(%eax)
1.1 fvdl 1277: sti
1278: /* Pushed T_ASTFLT into tf_trapno on entry. */
1.15 fvdl 1279: pushl %esp
1.1 fvdl 1280: call _C_LABEL(trap)
1.15 fvdl 1281: addl $4,%esp
1.27 yamt 1282: jmp .Lsyscall_checkast /* re-check ASTs */
1.24 yamt 1283: 1: CHECK_DEFERRED_SWITCH(%eax)
1284: jnz 9f
1.1 fvdl 1285: #ifndef DIAGNOSTIC
1.24 yamt 1286: INTRFASTEXIT
1.1 fvdl 1287: #else /* DIAGNOSTIC */
1.24 yamt 1288: cmpl $IPL_NONE,CPUVAR(ILEVEL)
1.1 fvdl 1289: jne 3f
1290: INTRFASTEXIT
1291: 3: sti
1292: pushl $4f
1293: call _C_LABEL(printf)
1294: addl $4,%esp
1295: #ifdef DDB
1296: int $3
1297: #endif /* DDB */
1298: movl $IPL_NONE,CPUVAR(ILEVEL)
1299: jmp 2b
1300: 4: .asciz "WARNING: SPL NOT LOWERED ON SYSCALL EXIT\n"
1.30 junyoung 1301: 5: .asciz "WARNING: SPL NOT ZERO ON SYSCALL ENTRY\n"
1302: 6: .asciz "WARNING: WANT PMAPLOAD ON SYSCALL ENTRY\n"
1.1 fvdl 1303: #endif /* DIAGNOSTIC */
1.24 yamt 1304: 9: sti
1305: call _C_LABEL(pmap_load)
1.27 yamt 1306: jmp .Lsyscall_checkast /* re-check ASTs */
1.1 fvdl 1307:
1308: #if NNPX > 0
1309: /*
1310: * Special interrupt handlers. Someday intr0-intr15 will be used to count
1311: * interrupts. We'll still need a special exception 16 handler. The busy
1312: * latch stuff in probintr() can be moved to npxprobe().
1313: */
1314:
1315: /* LINTSTUB: Func: void probeintr(void) */
1316: NENTRY(probeintr)
1317: ss
1318: incl _C_LABEL(npx_intrs_while_probing)
1319: pushl %eax
1320: movb $0x20,%al # EOI (asm in strings loses cpp features)
1321: outb %al,$0xa0 # IO_ICU2
1322: outb %al,$0x20 # IO_ICU1
1323: movb $0,%al
1324: outb %al,$0xf0 # clear BUSY# latch
1325: popl %eax
1326: iret
1327:
1328: /* LINTSTUB: Func: void probetrap(void) */
1329: NENTRY(probetrap)
1330: ss
1331: incl _C_LABEL(npx_traps_while_probing)
1332: fnclex
1333: iret
1334:
1335: /* LINTSTUB: Func: int npx586bug1(int a, int b) */
1336: NENTRY(npx586bug1)
1337: fildl 4(%esp) # x
1338: fildl 8(%esp) # y
1339: fld %st(1)
1340: fdiv %st(1),%st # x/y
1341: fmulp %st,%st(1) # (x/y)*y
1342: fsubrp %st,%st(1) # x-(x/y)*y
1343: pushl $0
1344: fistpl (%esp)
1345: popl %eax
1346: ret
1347: #endif /* NNPX > 0 */
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