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|
/* $OpenBSD: gidt.S,v 1.21 1998/04/18 07:39:51 deraadt Exp $ */
/*
* Copyright (c) 1997 Michael Shalayeff
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Michael Shalayeff.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
.file "gidt.S"
#include <machine/asm.h>
#define _LOCORE
#include <machine/trap.h>
#include <debug_md.h>
#undef _LOCORE
#include <assym.h>
#define addr32 .byte 0x67
#define data32 .byte 0x66
#define SNULL 0x00
#define S32TEXT 0x08
#define S32DATA 0x10
#define S16TEXT 0x18
#define S16DATA 0x20
#ifdef GIDT_DEBUG
#define gidt_debug0 ; \
movl $0xb8000, %eax ; \
movl $0x47314730, (%eax)
#define gidt_debug1 ; \
data32 ; \
movl $(0xb8000 - LINKADDR), %eax ; \
data32 ; \
addr32 ; \
movl $0x4f314f30, (%eax)
#define gidt_debug2 ; \
data32 ; \
movl $0xb8004, %eax ; \
data32 ; \
addr32 ; \
movl $0x47334732, (%eax)
#define gidt_debug3 ; \
data32 ; \
movl $0xb8004, %eax ; \
data32 ; \
addr32 ; \
movl $0x4f334f32, (%eax)
#define gidt_debug4 ; \
movl $0xb8008, %eax ; \
movl $0x47344733, (%eax)
#else
#define gidt_debug0 /* gidt_debug0 */
#define gidt_debug1 /* gidt_debug1 */
#define gidt_debug2 /* gidt_debug2 */
#define gidt_debug3 /* gidt_debug3 */
#define gidt_debug4 /* gidt_debug4 */
#endif
#define prot2real \
gidt_debug0; \
\
movl $S16DATA, %ax; \
/* ljmp $S16TEXT, $1f */; \
.byte 0xea; /* Change to 16bit mode */ \
.long 1f - LINKADDR; \
.word S16TEXT; \
1: \
movl %ax, %ds; \
movl %ax, %es; \
gidt_debug1; \
\
movl %cr0, %eax; /* disable pmmm */ \
data32; \
andl $~CR0_PE, %eax; \
movl %eax, %cr0; \
\
/* ljmp (LINKADDR >> 4), $1f */; \
.byte 0xea; /* load real mode cs:ip */ \
.word 1f; \
.word (LINKADDR >> 4); \
1: \
data32; \
xorl %eax, %eax; /* setup: %ds, %es, %ss */ \
movl %ax, %ds; \
movl %ax, %es; \
movl %ax, %ss; \
\
gidt_debug2; \
\
addr32; \
data32; \
lidt Idtr_real; /* load idtr for real mode */
#define real2prot \
gidt_debug3; \
\
addr32; \
data32; \
lgdt Gdtr; /* load the gdtr */ \
\
movl %cr0, %eax; /* enable pmmm */ \
data32; \
orl $CR0_PE, %eax; \
movl %eax, %cr0; \
\
data32; \
ljmp $S32TEXT, $1f; /* reload %cs flush pipeline */\
1: \
/* reload 32bit %ds, %ss, %es */ \
movl $S32DATA, %eax; \
movl %ax, %ds; \
movl %ax, %ss; \
movl %ax, %es; \
\
gidt_debug4; \
\
/* load idtr for debugger and DOS/BIOS iface */ \
lidt Idtr;
.globl _C_LABEL(BIOS_regs)
.text
.globl _ASM_LABEL(pmm_init)
.globl _C_LABEL(_rtt)
ENTRY(_rtt)
#ifdef GIDT_DEBUG
movl $0xb8000, %ebx
movl $0x4f514f51, (%ebx)
#endif
movw $0x1234, %ax
movw %ax, 0x472 /* warm boot */
/* Try to use the KBD to reboot system */
movb $0xfe, %al
outb %al, $0x64
movl $0x5000, %ecx
1: inb $0x84, %al
loop 1b
movb $0xfe, %al
outb %al, $0x64
#ifdef GIDT_DEBUG
movl $0xb8000, %ebx
movl $0x07310731, (%ebx)
#endif
/* Try to cause a tripple fault... */
lidt Idtr_reset
xorl %eax, %eax
divl %eax, %eax
/* Again... */
int $0x8
/* Again... */
movl $0, %esp /* segment violation */
ret
.align 3, 0x90
pmm_init:
/* reload new gdt */
lgdt Gdtr
ljmp $S32TEXT, $1f
1:
movl $S32DATA, %eax
movl %eax, %ds
movl %eax, %ss
movl %eax, %es
movl %eax, %fs
movl %eax, %gs
/* load idtr for interrupts */
lidt Idtr
ret
#define IPROC(n) X/**/n
#define IEMU(n) IPROC(emu/**/n)
.align 3
idt:
#define idte(e) \
.word IPROC(e), S32TEXT, (0x80|SDT_SYS386TGT) << 8, (LINKADDR >> 16)
/* internal (0-31) */
idte(de); idte(db); idte(nmi); idte(bp); idte(of); idte(br)
idte(ud); idte(nm); idte(df); idte(fo); idte(ts); idte(np)
idte(ss); idte(gp); idte(pf); idte(xx); idte(mf); idte(ac)
idte(mc)
idte(xx); idte(xx); idte(xx); idte(xx); idte(xx); idte(xx)
idte(xx); idte(xx); idte(xx); idte(xx); idte(xx); idte(xx)
idte(xx)
/* Maskable interrupts (32-255) */
/* BIOS entry points (32-63) */
/* DOS entry points (64-80) */
#define idtb(b) idte(emu/**/b)
idtb(0); idtb(1); idtb(2); idtb(3); idtb(4); idtb(5)
idtb(6); idtb(7); idtb(8); idtb(9); idtb(10); idtb(11)
idtb(12); idtb(13); idtb(14); idtb(15); idtb(16); idtb(17)
idtb(18); idtb(19); idtb(20); idtb(21); idtb(22); idtb(23)
idtb(24); idtb(25); idtb(26); idtb(27); idtb(28); idtb(29)
idtb(30); idtb(31); idtb(32); idtb(33); idtb(34); idtb(35)
idtb(36); idtb(37); idtb(38); idtb(39); idtb(40); idtb(41)
idtb(42); idtb(43); idtb(44); idtb(45); idtb(46); idtb(47)
#undef idte
Idtr: .word . - idt - 1
.long idt
.word 0
.align 3
Idtr_real: .word 1023
.long 0
.word 0
.align 3
Idtr_reset: .long 0, 0
.align 3
gdt:
/* 0x00 : null */
.space 8
/* 0x08 : flat code */
.word 0xFFFF # lolimit
.word 0 # lobase
.byte 0 # midbase
.byte SDT_MEMERAC | 0 | 0x80 # RXAC, dpl = 0, present
.byte 0xf | 0 | 0x40 | 0x80 # hilimit, xx, 32bit, 4k granularity
.byte 0 # hibase
/* 0x10 : flat data */
.word 0xFFFF # lolimit
.word 0 # lobase
.byte 0 # midbase
.byte SDT_MEMRWA | 0 | 0x80 # RWA, dpl = 0, present
.byte 0xf | 0 | 0x40 | 0x80 # hilimit, xx, 32bit, 4k granularity
.byte 0 # hibase
/* 0x18 : 16 bit code */
.word 0xFFFF # lolimit
.word (LINKADDR & 0xffff) # lobase
.byte (LINKADDR >> 16) & 0xff # midbase
.byte SDT_MEMERAC | 0 | 0x80 # RXAC, dpl = 0, present
.byte 0xf | 0 | 0 | 0 # hilimit, xx, 16bit, byte granularity
.byte (LINKADDR >> 20) & 0xff # hibase
/* 0x20 : 16 bit data */
.word 0xFFFF # lolimit
.word (LINKADDR & 0xffff) # lobase
.byte (LINKADDR >> 16) & 0xff # midbase
.byte SDT_MEMRWA | 0 | 0x80 # RWA, dpl = 0, present
.byte 0xf | 0 | 0 | 0 # hilimit, xx, 16bit, byte granularity
.byte (LINKADDR >> 20) & 0xff # hibase
Gdtr: .word . - gdt - 1
.long gdt
.word 0
#define IENTRY(name,type) \
IPROC(name): \
pushl $type ; \
jmp 1f
#define IENTRY_ERR(name,err,type) \
IPROC(name): \
pushl $err ; \
pushl $type ; \
jmp 1f
IPROC(xx):
pushl $1
pushl $T_RESERVED
jmp 1f
IENTRY_ERR(de,0,T_DIVIDE) /* #DE divide by zero */
IENTRY_ERR(db,0,T_TRCTRAP) /* #DB debug */
IENTRY_ERR(nmi,0,T_NMI) /* NMI */
IENTRY_ERR(bp,0,T_BPTFLT) /* #BP breakpoint */
IENTRY_ERR(of,0,T_OFLOW) /* #OF overflow */
IENTRY_ERR(br,0,T_BOUND) /* #BR BOUND range exceeded */
IENTRY_ERR(ud,0,T_PRIVINFLT) /* #UD invalid opcode */
IENTRY_ERR(nm,0,T_DNA) /* #NM device not available */
IENTRY(df,T_DOUBLEFLT) /* #DF double fault */
IENTRY_ERR(fo,0,T_FPOPFLT) /* #FO coprocessor segment overrun */
IENTRY(ts,T_TSSFLT) /* #TS innvalid TSS */
IENTRY(np,T_SEGNPFLT) /* #NP segmant not present */
IENTRY(ss,T_STKFLT) /* #SS stack fault */
IENTRY(gp,T_PROTFLT) /* #GP general protection */
IENTRY(pf,T_PAGEFLT) /* #PF page fault */
IENTRY_ERR(mf,0,T_ARITHTRAP) /* #MF floating point error */
IENTRY(ac,T_ALIGNFLT) /* #AC alignment check */
IENTRY(mc,T_MACHK) /* #MC machine check */
.globl alltraps
1: /* save on jumps */
jmp alltraps
#define IEMUENT(n) IEMU(n): pushl $n; jmp 1f
IEMUENT(0); IEMUENT(1); IEMUENT(2); IEMUENT(3)
IEMUENT(4); IEMUENT(5); IEMUENT(6); IEMUENT(7)
IEMUENT(8); IEMUENT(9); IEMUENT(10); IEMUENT(11)
IEMUENT(12); IEMUENT(13); IEMUENT(14); IEMUENT(15)
IEMUENT(16); IEMUENT(17); IEMUENT(18); IEMUENT(19)
IEMUENT(20); IEMUENT(21); IEMUENT(22); IEMUENT(23)
IEMUENT(24); IEMUENT(25); IEMUENT(26); IEMUENT(27)
IEMUENT(28); IEMUENT(29); IEMUENT(30); IEMUENT(31)
1: jmp EMUh /* redirect for short jumps */
IEMUENT(32); IEMUENT(33); IEMUENT(34); IEMUENT(35)
IEMUENT(36); IEMUENT(37); IEMUENT(38); IEMUENT(39)
IEMUENT(40); IEMUENT(41); IEMUENT(42); IEMUENT(43)
IEMUENT(44); IEMUENT(45); IEMUENT(46); IEMUENT(47)
1: jmp EMUh
/*
* entry point for BIOS real-mode interface
* all the magic for real-prot mode switching is here
*
* Call: %eax, %ecx, %edx, %ebx, %ebp, %esi, %edi, %es, %ds
* Return: %eax, %edx, %ecx, %eflags (as returned from BIOS)
*
*/
.globl EMUh
.align 3, 0x90
EMUh:
/* save %eax */
movl %eax, 3f
popl %eax
pushal
pushl %ds
pushl %es
pushl %fs
pushl %gs
/* save BIOS int vector */
movb %al, intno
prot2real
pushl %ds
addr32
movl _C_LABEL(BIOS_regs)+(biosr_es), %eax
movl %ax, %es
addr32
movl _C_LABEL(BIOS_regs)+(biosr_ds), %eax
movl %ax, %ds
data32
# movl Leax, %eax
.byte 0xb8
3: .long 0x90909090 /* restore %eax */
;sti
int $0
intno = . - 1
;cli
popl %ds
addr32
data32
movl %ebx, _C_LABEL(BIOS_regs)+(biosr_bx)
movl %es, %bx
addr32
movl %bx, _C_LABEL(BIOS_regs)+(biosr_es)
movb %ah, %bh /* save flags to return to caller */
lahf
xchgb %ah, %bh
addr32
data32
movl %eax, 2f /* save %eax */
real2prot
# movl Leax, %eax
.byte 0xb8
2: .long 0x90909090 /* eax */
/* pass BIOS return values back to caller */
movl %eax, 0xb*4(%esp)
movl %ecx, 0xa*4(%esp)
movl %edx, 0x9*4(%esp)
movb %bh , 0xe*4(%esp)
/* save registers into save area */
movl %eax, _C_LABEL(BIOS_regs)+biosr_ax
movl %ecx, _C_LABEL(BIOS_regs)+biosr_cx
movl %edx, _C_LABEL(BIOS_regs)+biosr_dx
movl %ebp, _C_LABEL(BIOS_regs)+biosr_bp
movl %esi, _C_LABEL(BIOS_regs)+biosr_si
movl %edi, _C_LABEL(BIOS_regs)+biosr_di
popl %gs
popl %fs
popl %es
popl %ds
popal
iret
/* Call buffer at 07c0:0000 in real mode to simulate a BIOS boot */
ENTRY(bootbuf)
popl %eax /* Don't need return address */
popl %esi /* Buffer */
popl %edx /* Device */
prot2real /* Switch */
/* Set up stack */
cli
xorl %ax, %ax
movl %ax, %ss
data32
movl $0xfffc, %esp
sti
/* Jump to buffer */
addr32
ljmp $0x0, $0x7c00
|