Clean up all of the 16-bit assembly code in the x86 bootstrap to work
with the new binutils. Now that we have a decent assembler, all the old m4 macros are no longer needed. Instead, straight assembly can be used since as(1) now understands 16-bit addressing, branches, etc. Also, several bugs have been fixed in as(1), allowing boot0.s to be further cleaned up.
This commit is contained in:
John Baldwin
parent
716f301734
commit
638bac9fc0
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=60821
@ -22,9 +22,9 @@ boot0: boot0.o
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objcopy -S -O binary boot0.out ${.TARGET}
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.endif
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boot0.o: boot0.m4 boot0.s
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(cd ${.CURDIR}; ${M4} -DFLAGS=${B0FLAGS} -DTICKS=${B0TICKS} \
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boot0.m4 boot0.s) | ${AS} ${AFLAGS} -o ${.TARGET}
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boot0.o: boot0.s
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${AS} ${AFLAGS} --defsym FLAGS=${B0FLAGS} --defsym TICKS=${B0TICKS} \
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${.IMPSRC} -o ${.TARGET}
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CLEANFILES+= boot0.out boot0.o
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@ -1,77 +0,0 @@
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#
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# Copyright (c) 1998 Robert Nordier
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms are freely
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# permitted provided that the above copyright notice and this
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# paragraph and the following disclaimer are duplicated in all
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# such forms.
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#
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# This software is provided "AS IS" and without any express or
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# implied warranties, including, without limitation, the implied
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# warranties of merchantability and fitness for a particular
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# purpose.
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#
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# $FreeBSD$
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define(_al,0x0)dnl
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define(_cl,0x1)dnl
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define(_dl,0x2)dnl
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define(_bl,0x3)dnl
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define(_ah,0x4)dnl
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define(_ch,0x5)dnl
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define(_dh,0x6)dnl
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define(_bh,0x7)dnl
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define(_ax,0x0)dnl
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define(_cx,0x1)dnl
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define(_dx,0x2)dnl
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define(_bx,0x3)dnl
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define(_sp,0x4)dnl
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define(_bp,0x5)dnl
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define(_si,0x6)dnl
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define(_di,0x7)dnl
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define(_es,0x0)dnl
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define(_cs,0x1)dnl
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define(_ss,0x2)dnl
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define(_ds,0x3)dnl
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define(_fs,0x4)dnl
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define(_gs,0x5)dnl
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define(_bx_si,0x0)dnl
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define(_bx_di,0x1)dnl
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define(_bp_si,0x2)dnl
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define(_bp_di,0x3)dnl
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define(_si_,0x4)dnl
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define(_di_,0x5)dnl
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define(_bp_,0x6)dnl
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define(_bx_,0x7)dnl
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define(o16,`.byte 0x66')dnl
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define(addw1r,`.byte 0x3; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
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define(addwia,`.byte 0x5; .word $1')dnl
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define(btwr1,`.word 0xa30f; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
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define(btswr1,`.word 0xab0f; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
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define(cmpbmr,`.byte 0x3a; .byte 0x6 | ($2 << 0x3); .word $1')dnl
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define(cmpw1r,`.byte 0x3b; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
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define(cmpwi2,`.byte 0x81; .byte 0xb8 | $3; .word $2; .word $1')dnl
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define(addwir,`.byte 0x83; .byte 0xc0 | $2; .byte $1')dnl
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define(movbr0,`.byte 0x88; .byte ($1 << 0x3) | $2')dnl
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define(movbr1,`.byte 0x88; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
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define(movwr1,`.byte 0x89; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
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define(movb0r,`.byte 0x8a; .byte ($2 << 0x3) | $1')dnl
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define(addb0r,`.byte 0x2; .byte ($2 << 0x3) | $1')dnl
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define(movb1r,`.byte 0x8a; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
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define(movw1r,`.byte 0x8b; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
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define(movws1,`.byte 0x8c; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
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define(movwir,`.byte 0xb8 | $2; .word $1')dnl
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define(movbi0,`.byte 0xc6; .byte $2; .byte $1')dnl
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define(callwi,`.byte 0xe8; .word $1 - . - 0x2')dnl
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define(jmpnwi,`.byte 0xe9; .word $1 - . - 0x2')dnl
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define(tstbi1,`.byte 0xf6; .byte 0x40 | $3; .byte $2; .byte $1')dnl
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define(incb1,`.byte 0xfe; .byte 0x40 | $2; .byte $1')dnl
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define(pushw1,`.byte 0xff; .byte 0x70 | $2; .byte $1')dnl
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define(retn,`.byte 0xc3')dnl
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@ -79,32 +79,23 @@ start: cld # String ops inc
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#
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# Relocate to the new copy of the code.
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#
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incb1(-0xe,_di_) # Sector number
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/* incb $-0xe(%di) */
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jmpnwi(main-LOAD+ORIGIN) # To relocated code
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/* jmp main-LOAD+ORIGIN */
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incb -0xe(%di) # Sector number
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jmp main-LOAD+ORIGIN # To relocated code
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#
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# Check what flags were loaded with us, specifically, Use a predefined Drive.
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# If what the bios gives us is bad, use the '0' in the block instead, as well.
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#
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main: tstbi1(0x20,_FLAGS,_bp_) # Set number drive?
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/* testb $(0x20+_FLAGS)(%bp) */
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.code32
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main: testb $0x20,_FLAGS(%bp) # Set number drive?
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jnz main.1 # Yes
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.code16
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testb %dl,%dl # Drive number valid?
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.code32
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js main.2 # Possibly (0x80 set)
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.code16
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main.1: movb1r(_SETDRV,_bp_,_dl) # Drive number to use
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/* movb $_SETDRV(%bp),%dl */
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main.1: movb _SETDRV(%bp),%dl # Drive number to use
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#
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# Whatever we decided to use, now store it into the fake
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# partition entry that lives in the data space above us.
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#
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main.2: movbr1(_dl,_FAKE,_bp_) # Save drive number
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/* movb %dl,$_FAKE(%bp) */
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callwi(putn) # To new line
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main.2: movb %dl,_FAKE(%bp) # Save drive number
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callw putn # To new line
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pushw %dx # Save drive number
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#
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# Start out with a pointer to the 4th byte of the first table entry
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@ -119,51 +110,39 @@ main.2: movbr1(_dl,_FAKE,_bp_) # Save drive number
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# Loop around on the partition table, printing values until we
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# pass a 256 byte boundary. The end of loop test is at main.5.
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#
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main.3: movbr1(_ch,-0x4,_bx_) # Zero active flag (ch == 0)
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/* movb %ch,$-0x4(%bx) */
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btwr1(_dx,_FLAGS,_bp_) # Entry enabled?
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/* bt %dx,$_FLAGS(%bp) */
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.code32
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main.3: movb %ch,-0x4(%bx) # Zero active flag (ch == 0)
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btw %dx,_FLAGS(%bp) # Entry enabled?
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jnc main.5 # No
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.code16
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#
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# If any of the entries in the table are
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# the same as the 'type' in the slice table entry,
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# then this is an empty or non bootable partition. Skip it.
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#
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movb0r(_bx_,_al) # Load type
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/* movb (%bx),%al */
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movb (%bx),%al # Load type
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movw $tables,%di # Lookup tables
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movb $TBL0SZ,%cl # Number of entries
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repne # Exclude
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scasb # partition?
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.code32
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je main.5 # Yes
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.code16
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#
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# Now scan the table of known types
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#
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movb $TBL1SZ,%cl # Number of entries
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repne # Known
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scasb # type?
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.code32
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jne main.4 # No
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.code16
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#
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# If it matches get the matching element in the
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# next array. if it doesn't, we are already
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# pointing at its first element which points to a "?".
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#
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addw $TBL1SZ,%di # Adjust
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main.4: movb0r(_di_,_cl) # Partition
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/* movb (%di),%cl */
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main.4: movb (%di),%cl # Partition
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addw %cx,%di # description
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callwi(putx) # Display it
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callw putx # Display it
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main.5: incw %dx # Next item
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addb $0x10,%bl # Next entry
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.code32
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jnc main.3 # Till done
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.code16
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#
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# Passed a 256 byte boundary..
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# table is finished.
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@ -172,16 +151,12 @@ main.5: incw %dx # Next item
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popw %ax # Drive number
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subb $0x80-0x1,%al # Does next
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cmpb NHRDRV,%al # drive exist? (from BIOS?)
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.code32
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jb main.6 # Yes
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.code16
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# If not then if there is only one drive,
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# Don't display drive as an option.
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#
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decw %ax # Already drive 0?
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.code32
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jz main.7 # Yes
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.code16
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# If it was illegal or we cycled through them,
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# then go back to drive 0.
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#
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@ -194,48 +169,38 @@ main.5: incw %dx # Next item
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# end of string.
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#
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main.6: addb $'0'|0x80,%al # Save next
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movbr1(_al,_NXTDRV,_bp_) # drive number
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/* movb %al,$NXTDRV(%bp) */
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movb %al,_NXTDRV(%bp) # drive number
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movw $drive,%di # Display
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callwi(putx) # item
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callw putx # item
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#
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# Now that we've printed the drive (if we needed to), display a prompt.
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# Get ready for the input byt noting the time.
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#
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main.7: movw $prompt,%si # Display
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callwi(putstr) # prompt
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movb1r(_OPT,_bp_,_dl) # Display
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/* movb $_OPT(%bp),%dl */
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callw putstr # prompt
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movb _OPT(%bp),%dl # Display
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decw %si # default
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callwi(putkey) # key
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callw putkey # key
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xorb %ah,%ah # BIOS: Get
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int $0x1a # system time
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movw %dx,%di # Ticks when
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addw1r(_TICKS,_bp_,_di) # timeout
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/* addw $_TICKS(%bp),%di */
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addw _TICKS(%bp),%di # timeout
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#
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# Busy loop, looking for keystrokes but
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# keeping one eye on the time.
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#
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main.8: movb $0x1,%ah # BIOS: Check
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int $0x16 # for keypress
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.code32
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jnz main.11 # Have one
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.code16
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xorb %ah,%ah # BIOS: Get
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int $0x1a # system time
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cmpw %di,%dx # Timeout?
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.code32
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jb main.8 # No
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.code16
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#
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# If timed out or defaulting, come here.
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#
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main.9: movb1r(_OPT,_bp_,_al) # Load default
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/* movb $_OPT(%bp),%al */
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.code32
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main.9: movb _OPT(%bp),%al # Load default
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jmp main.12 # Join common code
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.code16
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#
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# User's last try was bad, beep in displeasure.
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# Since nothing was printed, just continue on as if the user
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@ -244,7 +209,7 @@ main.9: movb1r(_OPT,_bp_,_al) # Load default
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# occurs or the user hits a good key.
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#
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main.10: movb $0x7,%al # Signal
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callwi(putchr) # error
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callw putchr # error
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#
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# Get the keystroke.
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#
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@ -255,18 +220,14 @@ main.11: xorb %ah,%ah # BIOS: Get
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# If it's CR act as if timed out.
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#
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cmpb $KEY_ENTER,%al # Enter pressed?
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.code32
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je main.9 # Yes
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.code16
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#
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# Otherwise check if legal
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# If not ask again.
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#
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subb $KEY_F1,%al # Less F1 scan code
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cmpb $0x4,%al # F1..F5?
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.code32
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ja main.10 # No
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.code16
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#
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# We have a selection.
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# but if it's a bad selection go back to complain.
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@ -274,54 +235,40 @@ main.11: xorb %ah,%ah # BIOS: Get
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# Anything not printed is not an option.
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#
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main.12: cbtw # Option
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btwr1(_ax,_MNUOPT,_bp_) # enabled?
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/* btw %ax,$_MNUOPT(%bp) */
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.code32
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btw %ax,_MNUOPT(%bp) # enabled?
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jnc main.10 # No
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.code16
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#
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# Save the info in the original tables
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# for rewriting to the disk.
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#
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movbr1(_al,_OPT,_bp_) # Save option
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/* movb %al,$OPT(%bp) */
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movb %al,_OPT(%bp) # Save option
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movw $FAKE,%si # Partition for write
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movb0r(_si_,_dl) # Drive number
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/* movb (%si),%dl */
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movb (%si),%dl # Drive number
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movw %si,%bx # Partition for read
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cmpb $0x4,%al # F5 pressed?
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pushf # Save
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.code32
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je main.13 # Yes
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.code16
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shlb $0x4,%al # Point to
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addw $partbl,%ax # selected
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xchgw %bx,%ax # partition
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movbi0(0x80,_bx_) # Flag active
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/* movb $0x80,(%bx) */
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movb $0x80,(%bx) # Flag active
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#
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# If not asked to do a write-back (flags 0x40) don't do one.
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#
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main.13: pushw %bx # Save
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tstbi1(0x40,_FLAGS,_bp_) # No updates?
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/* testb $0x40,$_FLAGS(%bp) */
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.code32
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testb $0x40,_FLAGS(%bp) # No updates?
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jnz main.14 # Yes
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.code16
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movw $start,%bx # Data to write
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movb $0x3,%ah # Write sector
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callwi(intx13) # to disk
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callw intx13 # to disk
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main.14: popw %si # Restore
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popf # Restore
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#
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# If going to next drive, replace drive with selected one.
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# Remember to un-ascii it. Hey 0x80 is already set, cool!
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#
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.code32
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jne main.15 # If not F5
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.code16
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movb1r(_NXTDRV,_bp_,_dl) # Next drive
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/* movb $_NXTDRV(%bp),%dl */
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movb _NXTDRV(%bp),%dl # Next drive
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subb $'0',%dl # number
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#
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# load selected bootsector to the LOAD location in RAM.
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@ -331,58 +278,43 @@ main.14: popw %si # Restore
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#
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main.15: movw $LOAD,%bx # Address for read
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movb $0x2,%ah # Read sector
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callwi(intx13) # from disk
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.code32
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callw intx13 # from disk
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jc main.10 # If error
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.code16
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cmpwi2(MAGIC,0x1fe,_bx_) # Bootable?
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/* cmpw $MAGIC,$0x1fe(%bx) */
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.code32
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cmpw $MAGIC,0x1fe(%bx) # Bootable?
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jne main.10 # No
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.code16
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pushw %si # Save
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movw $crlf,%si # Leave some
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callwi(puts) # space
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callw puts # space
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popw %si # Restore
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.code32
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jmp *%ebx # Invoke bootstrap
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/* jmp *%bx */
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.code16
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jmp *%bx # Invoke bootstrap
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#
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# Display routines
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#
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putkey: movb $'F',%al # Display
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callwi(putchr) # 'F'
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callw putchr # 'F'
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movb $'1',%al # Prepare
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addb %dl,%al # digit
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.code32
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jmp putstr.1 # Display the rest
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.code16
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#
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# Display the option and note that it is a valid option.
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# That last point is a bit tricky..
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#
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putx: btswr1(_dx,_MNUOPT,_bp_) # Enable menu option
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/* btsw %dx,$_MNUOPT(%bp) */
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putx: btsw %dx,_MNUOPT(%bp) # Enable menu option
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movw $item,%si # Display
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callwi(putkey) # key
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callw putkey # key
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movw %di,%si # Display the rest
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puts: callwi(putstr) # Display string
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puts: callw putstr # Display string
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putn: movw $crlf,%si # To next line
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putstr: lodsb # Get byte
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testb $0x80,%al # End of string?
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.code32
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jnz putstr.2 # Yes
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.code16
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putstr.1: callwi(putchr) # Display char
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.code32
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putstr.1: callw putchr # Display char
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jmp putstr # Continue
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.code16
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putstr.2: andb $~0x80,%al # Clear MSB
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putchr: pushw %bx # Save
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@ -390,26 +322,19 @@ putchr: pushw %bx # Save
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movb $0xe,%ah # BIOS: Display
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int $0x10 # character
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popw %bx # Restore
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retn # To caller
|
||||
retw # To caller
|
||||
|
||||
# One-sector disk I/O routine
|
||||
|
||||
intx13: movb1r(0x1,_si_,_dh) # Load head
|
||||
/* movb $0x1(%si),%dh */
|
||||
movw1r(0x2,_si_,_cx) # Load cylinder:sector
|
||||
/* movw $0x2(%si),%cx */
|
||||
intx13: movb 0x1(%si),%dh # Load head
|
||||
movw 0x2(%si),%cx # Load cylinder:sector
|
||||
movb $0x1,%al # Sector count
|
||||
pushw %si # Save
|
||||
movw %sp,%di # Save
|
||||
tstbi1(0x80,_FLAGS,_bp_) # Use packet interface?
|
||||
/* testb $0x80,$_FLAGS(%bp) */
|
||||
.code32
|
||||
testb $0x80,_FLAGS(%bp) # Use packet interface?
|
||||
jz intx13.1 # No
|
||||
.code16
|
||||
pushl $0x0 # Set the
|
||||
o16 # LBA
|
||||
pushw1(0x8,_si_) # address
|
||||
/* pushl $0x8(%si) */
|
||||
pushl 0x8(%si) # LBA address
|
||||
pushw %es # Set the transfer
|
||||
pushw %bx # buffer address
|
||||
push $0x1 # Block count
|
||||
@ -420,7 +345,7 @@ intx13: movb1r(0x1,_si_,_dh) # Load head
|
||||
intx13.1: int $0x13 # BIOS: Disk I/O
|
||||
movw %di,%sp # Restore
|
||||
popw %si # Restore
|
||||
retn # To caller
|
||||
retw # To caller
|
||||
|
||||
# Menu strings
|
||||
|
||||
|
||||
@ -9,8 +9,6 @@ CLEANFILES+= boot1 boot1.out boot1.o \
|
||||
boot2.ldr boot2.bin boot2.ld boot2.out boot2.o \
|
||||
sio.o
|
||||
|
||||
M4?= m4
|
||||
|
||||
# A value of 0x80 enables LBA support.
|
||||
B1FLAGS= 0
|
||||
|
||||
@ -45,9 +43,8 @@ boot1: boot1.out
|
||||
boot1.out: boot1.o
|
||||
${LD} ${LDFLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} boot1.o
|
||||
|
||||
boot1.o: boot1.m4 boot1.s
|
||||
(cd ${.CURDIR}; ${M4} -DFLAGS=${B1FLAGS} boot1.m4 boot1.s) | \
|
||||
${AS} ${AFLAGS} -o ${.TARGET}
|
||||
boot1.o: boot1.s
|
||||
${AS} ${AFLAGS} --defsym FLAGS=${B1FLAGS} ${.IMPSRC} -o ${.TARGET}
|
||||
|
||||
boot2: boot2.ldr boot2.bin ${BTX}/btx/btx
|
||||
btxld -v -E ${ORG2} -f bin -b ${BTX}/btx/btx -l boot2.ldr \
|
||||
@ -67,10 +64,10 @@ boot2.out: boot2.o sio.o
|
||||
${BTX}/lib/crt0.o boot2.o sio.o
|
||||
|
||||
sio.o: sio.s
|
||||
(cd ${.CURDIR}; ${M4} -DSIOPRT=${BOOT_COMCONSOLE_PORT} \
|
||||
-DSIOFMT=${B2SIOFMT} \
|
||||
-DSIOSPD=${BOOT_COMCONSOLE_SPEED} sio.s) | \
|
||||
${AS} ${AFLAGS} -o ${.TARGET}
|
||||
${AS} ${AFLAGS} --defsym SIOPRT=${BOOT_COMCONSOLE_PORT} \
|
||||
--defsym SIOFMT=${B2SIOFMT} \
|
||||
--defsym SIOSPD=${BOOT_COMCONSOLE_SPEED} \
|
||||
${.IMPSRC} -o ${.TARGET}
|
||||
|
||||
install:
|
||||
${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m ${BINMODE} \
|
||||
|
||||
@ -32,6 +32,7 @@
|
||||
|
||||
.globl start
|
||||
.globl xread
|
||||
.code16
|
||||
|
||||
start: jmp main # Start recognizably
|
||||
|
||||
@ -39,75 +40,75 @@ start: jmp main # Start recognizably
|
||||
|
||||
# External read from disk
|
||||
|
||||
xread: pushl %ss # Address
|
||||
popl %ds # data
|
||||
xread.1: o16 # Starting
|
||||
pushb $0x0 # absolute
|
||||
pushl %ecx # block
|
||||
pushl %eax # number
|
||||
pushl %es # Address of
|
||||
pushl %ebx # transfer buffer
|
||||
xorl %eax,%eax # Number of
|
||||
xread: push %ss # Address
|
||||
pop %ds # data
|
||||
xread.1: # Starting
|
||||
pushl $0x0 # absolute
|
||||
push %cx # block
|
||||
push %ax # number
|
||||
push %es # Address of
|
||||
push %bx # transfer buffer
|
||||
xor %ax,%ax # Number of
|
||||
movb %dh,%al # blocks to
|
||||
pushl %eax # transfer
|
||||
pushb $0x10 # Size of packet
|
||||
movl %esp,%ebp # Packet pointer
|
||||
callwi(read) # Read from disk
|
||||
leaw1r(0x10,_bp_,_sp) # Clear stack
|
||||
push %ax # transfer
|
||||
push $0x10 # Size of packet
|
||||
mov %sp,%bp # Packet pointer
|
||||
callw read # Read from disk
|
||||
lea 0x10(%bp),%sp # Clear stack
|
||||
lret # To far caller
|
||||
|
||||
# Bootstrap
|
||||
|
||||
main: cld # String ops inc
|
||||
xorl %ecx,%ecx # Zero
|
||||
movl %cx,%es # Address
|
||||
movl %cx,%ds # data
|
||||
movl %cx,%ss # Set up
|
||||
movwir(start,_sp) # stack
|
||||
movl %esp,%esi # Source
|
||||
movwir(MEM_REL,_di) # Destination
|
||||
xor %cx,%cx # Zero
|
||||
mov %cx,%es # Address
|
||||
mov %cx,%ds # data
|
||||
mov %cx,%ss # Set up
|
||||
mov $start,%sp # stack
|
||||
mov %sp,%si # Source
|
||||
mov $MEM_REL,%di # Destination
|
||||
incb %ch # Word count
|
||||
rep # Copy
|
||||
movsl # code
|
||||
movwir(part4,_si) # Partition
|
||||
movsw # code
|
||||
mov $part4,%si # Partition
|
||||
cmpb $0x80,%dl # Hard drive?
|
||||
jb main.4 # No
|
||||
movb $0x1,%dh # Block count
|
||||
callwi(nread) # Read MBR
|
||||
movwir(0x1,_cx) # Two passes
|
||||
main.1: movwir(MEM_BUF+PRT_OFF,_si) # Partition table
|
||||
callw nread # Read MBR
|
||||
mov $0x1,%cx # Two passes
|
||||
main.1: mov $MEM_BUF+PRT_OFF,%si # Partition table
|
||||
movb $0x1,%dh # Partition
|
||||
main.2: cmpbi1(PRT_BSD,0x4,_si_) # Our partition type?
|
||||
main.2: cmpb $PRT_BSD,0x4(%si) # Our partition type?
|
||||
jne main.3 # No
|
||||
jecxz main.5 # If second pass
|
||||
tstbi0(0x80,_si_) # Active?
|
||||
jcxz main.5 # If second pass
|
||||
testb $0x80,(%si) # Active?
|
||||
jnz main.5 # Yes
|
||||
main.3: addl $0x10,%esi # Next entry
|
||||
main.3: add $0x10,%si # Next entry
|
||||
incb %dh # Partition
|
||||
cmpb $0x1+PRT_NUM,%dh # In table?
|
||||
jb main.2 # Yes
|
||||
decl %ecx # Do two
|
||||
jecxz main.1 # passes
|
||||
movwir(msg_part,_si) # Message
|
||||
dec %cx # Do two
|
||||
jcxz main.1 # passes
|
||||
mov $msg_part,%si # Message
|
||||
jmp error # Error
|
||||
main.4: xorl %edx,%edx # Partition:drive
|
||||
main.5: movwrm(_dx,MEM_ARG) # Save args
|
||||
main.4: xor %dx,%dx # Partition:drive
|
||||
main.5: mov %dx,MEM_ARG # Save args
|
||||
movb $0x10,%dh # Sector count
|
||||
callwi(nread) # Read disk
|
||||
movwir(MEM_BTX,_bx) # BTX
|
||||
movw1r(0xa,_bx_,_si) # Point past
|
||||
addl %ebx,%esi # it
|
||||
movwir(MEM_USR+SIZ_PAG,_di) # Client page 1
|
||||
movwir(MEM_BTX+0xe*SIZ_SEC,_cx) # Byte
|
||||
subl %esi,%ecx # count
|
||||
callw nread # Read disk
|
||||
mov $MEM_BTX,%bx # BTX
|
||||
mov 0xa(%bx),%si # Point past
|
||||
add %bx,%si # it
|
||||
mov $MEM_USR+SIZ_PAG,%di # Client page 1
|
||||
mov $MEM_BTX+0xe*SIZ_SEC,%cx # Byte
|
||||
sub %si,%cx # count
|
||||
rep # Relocate
|
||||
movsb # client
|
||||
subl %edi,%ecx # Byte count
|
||||
sub %di,%cx # Byte count
|
||||
xorb %al,%al # Zero
|
||||
rep # assumed
|
||||
stosb # bss
|
||||
callwi(seta20) # Enable A20
|
||||
jmpnwi(start+MEM_JMP-MEM_ORG) # Start BTX
|
||||
callw seta20 # Enable A20
|
||||
jmp start+MEM_JMP-MEM_ORG # Start BTX
|
||||
|
||||
# Enable A20
|
||||
|
||||
@ -123,30 +124,30 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
# Local read from disk
|
||||
|
||||
nread: movwir(MEM_BUF,_bx) # Transfer buffer
|
||||
movw1r(0x8,_si_,_ax) # Get
|
||||
movw1r(0xa,_si_,_cx) # LBA
|
||||
pushl %cs # Read from
|
||||
callwi(xread.1) # disk
|
||||
nread: mov $MEM_BUF,%bx # Transfer buffer
|
||||
mov 0x8(%si),%ax # Get
|
||||
mov 0xa(%si),%cx # LBA
|
||||
push %cs # Read from
|
||||
callw xread.1 # disk
|
||||
jnc return # If success
|
||||
movwir(msg_read,_si) # Message
|
||||
mov $msg_read,%si # Message
|
||||
|
||||
# Error exit
|
||||
|
||||
error: callwi(putstr) # Display message
|
||||
movwir(prompt,_si) # Display
|
||||
callwi(putstr) # prompt
|
||||
error: callw putstr # Display message
|
||||
mov $prompt,%si # Display
|
||||
callw putstr # prompt
|
||||
xorb %ah,%ah # BIOS: Get
|
||||
int $0x16 # keypress
|
||||
int $0x19 # BIOS: Reboot
|
||||
|
||||
# Display string
|
||||
|
||||
putstr.0: movwir(0x7,_bx) # Page:attribute
|
||||
putstr.0: mov $0x7,%bx # Page:attribute
|
||||
movb $0xe,%ah # BIOS: Display
|
||||
int $0x10 # character
|
||||
putstr: lodsb # Get char
|
||||
@ -155,87 +156,84 @@ putstr: lodsb # Get char
|
||||
|
||||
ereturn: movb $0x1,%ah # Invalid
|
||||
stc # argument
|
||||
return: ret # To caller
|
||||
return: retw # To caller
|
||||
|
||||
# Read from disk
|
||||
|
||||
read: cs_ # LBA support
|
||||
tstbim(0x80,MEM_REL+flags-start)# enabled?
|
||||
read: testb $0x80,%cs:MEM_REL+flags-start # LBA support enabled?
|
||||
jz read.1 # No
|
||||
movwir(0x55aa,_bx) # Magic
|
||||
pushl %edx # Save
|
||||
mov $0x55aa,%bx # Magic
|
||||
push %dx # Save
|
||||
movb $0x41,%ah # BIOS: Check
|
||||
int $0x13 # extensions present
|
||||
popl %edx # Restore
|
||||
pop %dx # Restore
|
||||
jc read.1 # If error
|
||||
cmpwir(0xaa55,_bx) # Magic?
|
||||
cmp $0xaa55,%bx # Magic?
|
||||
jne read.1 # No
|
||||
testb $0x1,%cl # Packet interface?
|
||||
jz read.1 # No
|
||||
movl %ebp,%esi # Disk packet
|
||||
mov %bp,%si # Disk packet
|
||||
movb $0x42,%ah # BIOS: Extended
|
||||
int $0x13 # read
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
read.1: pushl %edx # Save
|
||||
read.1: push %dx # Save
|
||||
movb $0x8,%ah # BIOS: Get drive
|
||||
int $0x13 # parameters
|
||||
movb %dh,%ch # Max head number
|
||||
popl %edx # Restore
|
||||
pop %dx # Restore
|
||||
jc return # If error
|
||||
andb $0x3f,%cl # Sectors per track
|
||||
jz ereturn # If zero
|
||||
cli # Disable interrupts
|
||||
o16 # Get
|
||||
movw1r(0x8,_bp_,_ax) # LBA
|
||||
pushl %edx # Save
|
||||
movzbw %cl,%bx # Divide by
|
||||
xorw %dx,%dx # sectors
|
||||
divw %bx,%ax # per track
|
||||
mov 0x8(%bp),%eax # Get LBA
|
||||
push %dx # Save
|
||||
movzbl %cl,%ebx # Divide by
|
||||
xor %edx,%edx # sectors
|
||||
div %ebx # per track
|
||||
movb %ch,%bl # Max head number
|
||||
movb %dl,%ch # Sector number
|
||||
incl %ebx # Divide by
|
||||
inc %bx # Divide by
|
||||
xorb %dl,%dl # number
|
||||
divw %bx,%ax # of heads
|
||||
div %ebx # of heads
|
||||
movb %dl,%bh # Head number
|
||||
popl %edx # Restore
|
||||
o16 # Cylinder number
|
||||
cmpl $0x3ff,%eax # supportable?
|
||||
pop %dx # Restore
|
||||
cmpl $0x3ff,%eax # Cylinder number supportable?
|
||||
sti # Enable interrupts
|
||||
ja ereturn # No
|
||||
xchgb %al,%ah # Set up cylinder
|
||||
rorb $0x2,%al # number
|
||||
orb %ch,%al # Merge
|
||||
incl %eax # sector
|
||||
xchgl %eax,%ecx # number
|
||||
inc %ax # sector
|
||||
xchg %ax,%cx # number
|
||||
movb %bh,%dh # Head number
|
||||
subb %ah,%al # Sectors this track
|
||||
movb1r(0x2,_bp_,_ah) # Blocks to read
|
||||
mov 0x2(%bp),%ah # Blocks to read
|
||||
cmpb %ah,%al # To read
|
||||
jb read.2 # this
|
||||
movb %ah,%al # track
|
||||
read.2: movwir(0x5,_di) # Try count
|
||||
read.3: lesw1r(0x4,_bp_,_bx) # Transfer buffer
|
||||
pushl %eax # Save
|
||||
read.2: mov $0x5,%di # Try count
|
||||
read.3: les 0x4(%bp),%bx # Transfer buffer
|
||||
push %ax # Save
|
||||
movb $0x2,%ah # BIOS: Read
|
||||
int $0x13 # from disk
|
||||
popl %ebx # Restore
|
||||
pop %bx # Restore
|
||||
jnc read.4 # If success
|
||||
decl %edi # Retry?
|
||||
dec %di # Retry?
|
||||
jz read.6 # No
|
||||
xorb %ah,%ah # BIOS: Reset
|
||||
int $0x13 # disk system
|
||||
xchgl %ebx,%eax # Block count
|
||||
xchg %bx,%ax # Block count
|
||||
jmp read.3 # Continue
|
||||
read.4: movzbl %bl,%eax # Sectors read
|
||||
addwr1(_ax,0x8,_bp_) # Adjust
|
||||
read.4: movzbw %bl,%ax # Sectors read
|
||||
add %ax,0x8(%bp) # Adjust
|
||||
jnc read.5 # LBA,
|
||||
incw1(0xa,_bp_) # transfer
|
||||
incw 0xa(%bp) # transfer
|
||||
read.5: shlb %bl # buffer
|
||||
addbr1(_bl,0x5,_bp_) # pointer,
|
||||
subbr1(_al,0x2,_bp_) # block count
|
||||
add %bl,0x5(%bp) # pointer,
|
||||
sub %al,0x2(%bp) # block count
|
||||
ja read.1 # If not done
|
||||
read.6: ret # To caller
|
||||
read.6: retw # To caller
|
||||
|
||||
# Messages
|
||||
|
||||
|
||||
@ -1,66 +0,0 @@
|
||||
#
|
||||
# Copyright (c) 1998 Robert Nordier
|
||||
# All rights reserved.
|
||||
#
|
||||
# Redistribution and use in source and binary forms are freely
|
||||
# permitted provided that the above copyright notice and this
|
||||
# paragraph and the following disclaimer are duplicated in all
|
||||
# such forms.
|
||||
#
|
||||
# This software is provided "AS IS" and without any express or
|
||||
# implied warranties, including, without limitation, the implied
|
||||
# warranties of merchantability and fitness for a particular
|
||||
# purpose.
|
||||
#
|
||||
|
||||
# $FreeBSD$
|
||||
|
||||
define(_al,0x0)dnl
|
||||
define(_cl,0x1)dnl
|
||||
define(_dl,0x2)dnl
|
||||
define(_bl,0x3)dnl
|
||||
define(_ah,0x4)dnl
|
||||
define(_ch,0x5)dnl
|
||||
define(_dh,0x6)dnl
|
||||
define(_bh,0x7)dnl
|
||||
|
||||
define(_ax,0x0)dnl
|
||||
define(_cx,0x1)dnl
|
||||
define(_dx,0x2)dnl
|
||||
define(_bx,0x3)dnl
|
||||
define(_sp,0x4)dnl
|
||||
define(_bp,0x5)dnl
|
||||
define(_si,0x6)dnl
|
||||
define(_di,0x7)dnl
|
||||
|
||||
define(_bx_si,0x0)dnl
|
||||
define(_bx_di,0x1)dnl
|
||||
define(_bp_si,0x2)dnl
|
||||
define(_bp_di,0x3)dnl
|
||||
define(_si_,0x4)dnl
|
||||
define(_di_,0x5)dnl
|
||||
define(_bp_,0x6)dnl
|
||||
define(_bx_,0x7)dnl
|
||||
|
||||
define(cs_,`.byte 0x2e')dnl
|
||||
define(o16,`.byte 0x66')dnl
|
||||
|
||||
define(addbr1,`.byte 0x0; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(addwr1,`.byte 0x1; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(subbr1,`.byte 0x28; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(cmpbi1,`.byte 0x80; .byte 0x78 | $3; .byte $2; .byte $1')dnl
|
||||
define(cmpwir,`.byte 0x81; .byte 0xf8 | $2; .word $1')dnl
|
||||
define(movbr1,`.byte 0x88; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(movwr1,`.byte 0x89; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(movwrm,`.byte 0x89; .byte 0x6 | ($1 << 0x3); .word $2')dnl
|
||||
define(movb1r,`.byte 0x8a; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
|
||||
define(movw1r,`.byte 0x8b; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
|
||||
define(leaw1r,`.byte 0x8d; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
|
||||
define(movwir,`.byte 0xb8 | $2; .word $1')dnl
|
||||
define(lesw1r,`.byte 0xc4; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
|
||||
define(movbi1,`.byte 0xc6; .byte 0x40 | $3; .byte $2; .byte $1')dnl
|
||||
define(callwi,`.byte 0xe8; .word $1 - . - 0x2')dnl
|
||||
define(jmpnwi,`.byte 0xe9; .word $1 - . - 0x2')dnl
|
||||
define(tstbi0,`.byte 0xf6; .byte $2; .byte $1')dnl
|
||||
define(tstbim,`.byte 0xf6; .byte 0x6; .word $2; .byte $1')dnl
|
||||
define(incw1,`.byte 0xff; .byte 0x40 | $2; .byte $1')dnl
|
||||
@ -32,6 +32,7 @@
|
||||
|
||||
.globl start
|
||||
.globl xread
|
||||
.code16
|
||||
|
||||
start: jmp main # Start recognizably
|
||||
|
||||
@ -39,75 +40,75 @@ start: jmp main # Start recognizably
|
||||
|
||||
# External read from disk
|
||||
|
||||
xread: pushl %ss # Address
|
||||
popl %ds # data
|
||||
xread.1: o16 # Starting
|
||||
pushb $0x0 # absolute
|
||||
pushl %ecx # block
|
||||
pushl %eax # number
|
||||
pushl %es # Address of
|
||||
pushl %ebx # transfer buffer
|
||||
xorl %eax,%eax # Number of
|
||||
xread: push %ss # Address
|
||||
pop %ds # data
|
||||
xread.1: # Starting
|
||||
pushl $0x0 # absolute
|
||||
push %cx # block
|
||||
push %ax # number
|
||||
push %es # Address of
|
||||
push %bx # transfer buffer
|
||||
xor %ax,%ax # Number of
|
||||
movb %dh,%al # blocks to
|
||||
pushl %eax # transfer
|
||||
pushb $0x10 # Size of packet
|
||||
movl %esp,%ebp # Packet pointer
|
||||
callwi(read) # Read from disk
|
||||
leaw1r(0x10,_bp_,_sp) # Clear stack
|
||||
push %ax # transfer
|
||||
push $0x10 # Size of packet
|
||||
mov %sp,%bp # Packet pointer
|
||||
callw read # Read from disk
|
||||
lea 0x10(%bp),%sp # Clear stack
|
||||
lret # To far caller
|
||||
|
||||
# Bootstrap
|
||||
|
||||
main: cld # String ops inc
|
||||
xorl %ecx,%ecx # Zero
|
||||
movl %cx,%es # Address
|
||||
movl %cx,%ds # data
|
||||
movl %cx,%ss # Set up
|
||||
movwir(start,_sp) # stack
|
||||
movl %esp,%esi # Source
|
||||
movwir(MEM_REL,_di) # Destination
|
||||
xor %cx,%cx # Zero
|
||||
mov %cx,%es # Address
|
||||
mov %cx,%ds # data
|
||||
mov %cx,%ss # Set up
|
||||
mov $start,%sp # stack
|
||||
mov %sp,%si # Source
|
||||
mov $MEM_REL,%di # Destination
|
||||
incb %ch # Word count
|
||||
rep # Copy
|
||||
movsl # code
|
||||
movwir(part4,_si) # Partition
|
||||
movsw # code
|
||||
mov $part4,%si # Partition
|
||||
cmpb $0x80,%dl # Hard drive?
|
||||
jb main.4 # No
|
||||
movb $0x1,%dh # Block count
|
||||
callwi(nread) # Read MBR
|
||||
movwir(0x1,_cx) # Two passes
|
||||
main.1: movwir(MEM_BUF+PRT_OFF,_si) # Partition table
|
||||
callw nread # Read MBR
|
||||
mov $0x1,%cx # Two passes
|
||||
main.1: mov $MEM_BUF+PRT_OFF,%si # Partition table
|
||||
movb $0x1,%dh # Partition
|
||||
main.2: cmpbi1(PRT_BSD,0x4,_si_) # Our partition type?
|
||||
main.2: cmpb $PRT_BSD,0x4(%si) # Our partition type?
|
||||
jne main.3 # No
|
||||
jecxz main.5 # If second pass
|
||||
tstbi0(0x80,_si_) # Active?
|
||||
jcxz main.5 # If second pass
|
||||
testb $0x80,(%si) # Active?
|
||||
jnz main.5 # Yes
|
||||
main.3: addl $0x10,%esi # Next entry
|
||||
main.3: add $0x10,%si # Next entry
|
||||
incb %dh # Partition
|
||||
cmpb $0x1+PRT_NUM,%dh # In table?
|
||||
jb main.2 # Yes
|
||||
decl %ecx # Do two
|
||||
jecxz main.1 # passes
|
||||
movwir(msg_part,_si) # Message
|
||||
dec %cx # Do two
|
||||
jcxz main.1 # passes
|
||||
mov $msg_part,%si # Message
|
||||
jmp error # Error
|
||||
main.4: xorl %edx,%edx # Partition:drive
|
||||
main.5: movwrm(_dx,MEM_ARG) # Save args
|
||||
main.4: xor %dx,%dx # Partition:drive
|
||||
main.5: mov %dx,MEM_ARG # Save args
|
||||
movb $0x10,%dh # Sector count
|
||||
callwi(nread) # Read disk
|
||||
movwir(MEM_BTX,_bx) # BTX
|
||||
movw1r(0xa,_bx_,_si) # Point past
|
||||
addl %ebx,%esi # it
|
||||
movwir(MEM_USR+SIZ_PAG,_di) # Client page 1
|
||||
movwir(MEM_BTX+0xe*SIZ_SEC,_cx) # Byte
|
||||
subl %esi,%ecx # count
|
||||
callw nread # Read disk
|
||||
mov $MEM_BTX,%bx # BTX
|
||||
mov 0xa(%bx),%si # Point past
|
||||
add %bx,%si # it
|
||||
mov $MEM_USR+SIZ_PAG,%di # Client page 1
|
||||
mov $MEM_BTX+0xe*SIZ_SEC,%cx # Byte
|
||||
sub %si,%cx # count
|
||||
rep # Relocate
|
||||
movsb # client
|
||||
subl %edi,%ecx # Byte count
|
||||
sub %di,%cx # Byte count
|
||||
xorb %al,%al # Zero
|
||||
rep # assumed
|
||||
stosb # bss
|
||||
callwi(seta20) # Enable A20
|
||||
jmpnwi(start+MEM_JMP-MEM_ORG) # Start BTX
|
||||
callw seta20 # Enable A20
|
||||
jmp start+MEM_JMP-MEM_ORG # Start BTX
|
||||
|
||||
# Enable A20
|
||||
|
||||
@ -123,30 +124,30 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
# Local read from disk
|
||||
|
||||
nread: movwir(MEM_BUF,_bx) # Transfer buffer
|
||||
movw1r(0x8,_si_,_ax) # Get
|
||||
movw1r(0xa,_si_,_cx) # LBA
|
||||
pushl %cs # Read from
|
||||
callwi(xread.1) # disk
|
||||
nread: mov $MEM_BUF,%bx # Transfer buffer
|
||||
mov 0x8(%si),%ax # Get
|
||||
mov 0xa(%si),%cx # LBA
|
||||
push %cs # Read from
|
||||
callw xread.1 # disk
|
||||
jnc return # If success
|
||||
movwir(msg_read,_si) # Message
|
||||
mov $msg_read,%si # Message
|
||||
|
||||
# Error exit
|
||||
|
||||
error: callwi(putstr) # Display message
|
||||
movwir(prompt,_si) # Display
|
||||
callwi(putstr) # prompt
|
||||
error: callw putstr # Display message
|
||||
mov $prompt,%si # Display
|
||||
callw putstr # prompt
|
||||
xorb %ah,%ah # BIOS: Get
|
||||
int $0x16 # keypress
|
||||
int $0x19 # BIOS: Reboot
|
||||
|
||||
# Display string
|
||||
|
||||
putstr.0: movwir(0x7,_bx) # Page:attribute
|
||||
putstr.0: mov $0x7,%bx # Page:attribute
|
||||
movb $0xe,%ah # BIOS: Display
|
||||
int $0x10 # character
|
||||
putstr: lodsb # Get char
|
||||
@ -155,87 +156,84 @@ putstr: lodsb # Get char
|
||||
|
||||
ereturn: movb $0x1,%ah # Invalid
|
||||
stc # argument
|
||||
return: ret # To caller
|
||||
return: retw # To caller
|
||||
|
||||
# Read from disk
|
||||
|
||||
read: cs_ # LBA support
|
||||
tstbim(0x80,MEM_REL+flags-start)# enabled?
|
||||
read: testb $0x80,%cs:MEM_REL+flags-start # LBA support enabled?
|
||||
jz read.1 # No
|
||||
movwir(0x55aa,_bx) # Magic
|
||||
pushl %edx # Save
|
||||
mov $0x55aa,%bx # Magic
|
||||
push %dx # Save
|
||||
movb $0x41,%ah # BIOS: Check
|
||||
int $0x13 # extensions present
|
||||
popl %edx # Restore
|
||||
pop %dx # Restore
|
||||
jc read.1 # If error
|
||||
cmpwir(0xaa55,_bx) # Magic?
|
||||
cmp $0xaa55,%bx # Magic?
|
||||
jne read.1 # No
|
||||
testb $0x1,%cl # Packet interface?
|
||||
jz read.1 # No
|
||||
movl %ebp,%esi # Disk packet
|
||||
mov %bp,%si # Disk packet
|
||||
movb $0x42,%ah # BIOS: Extended
|
||||
int $0x13 # read
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
read.1: pushl %edx # Save
|
||||
read.1: push %dx # Save
|
||||
movb $0x8,%ah # BIOS: Get drive
|
||||
int $0x13 # parameters
|
||||
movb %dh,%ch # Max head number
|
||||
popl %edx # Restore
|
||||
pop %dx # Restore
|
||||
jc return # If error
|
||||
andb $0x3f,%cl # Sectors per track
|
||||
jz ereturn # If zero
|
||||
cli # Disable interrupts
|
||||
o16 # Get
|
||||
movw1r(0x8,_bp_,_ax) # LBA
|
||||
pushl %edx # Save
|
||||
movzbw %cl,%bx # Divide by
|
||||
xorw %dx,%dx # sectors
|
||||
divw %bx,%ax # per track
|
||||
mov 0x8(%bp),%eax # Get LBA
|
||||
push %dx # Save
|
||||
movzbl %cl,%ebx # Divide by
|
||||
xor %edx,%edx # sectors
|
||||
div %ebx # per track
|
||||
movb %ch,%bl # Max head number
|
||||
movb %dl,%ch # Sector number
|
||||
incl %ebx # Divide by
|
||||
inc %bx # Divide by
|
||||
xorb %dl,%dl # number
|
||||
divw %bx,%ax # of heads
|
||||
div %ebx # of heads
|
||||
movb %dl,%bh # Head number
|
||||
popl %edx # Restore
|
||||
o16 # Cylinder number
|
||||
cmpl $0x3ff,%eax # supportable?
|
||||
pop %dx # Restore
|
||||
cmpl $0x3ff,%eax # Cylinder number supportable?
|
||||
sti # Enable interrupts
|
||||
ja ereturn # No
|
||||
xchgb %al,%ah # Set up cylinder
|
||||
rorb $0x2,%al # number
|
||||
orb %ch,%al # Merge
|
||||
incl %eax # sector
|
||||
xchgl %eax,%ecx # number
|
||||
inc %ax # sector
|
||||
xchg %ax,%cx # number
|
||||
movb %bh,%dh # Head number
|
||||
subb %ah,%al # Sectors this track
|
||||
movb1r(0x2,_bp_,_ah) # Blocks to read
|
||||
mov 0x2(%bp),%ah # Blocks to read
|
||||
cmpb %ah,%al # To read
|
||||
jb read.2 # this
|
||||
movb %ah,%al # track
|
||||
read.2: movwir(0x5,_di) # Try count
|
||||
read.3: lesw1r(0x4,_bp_,_bx) # Transfer buffer
|
||||
pushl %eax # Save
|
||||
read.2: mov $0x5,%di # Try count
|
||||
read.3: les 0x4(%bp),%bx # Transfer buffer
|
||||
push %ax # Save
|
||||
movb $0x2,%ah # BIOS: Read
|
||||
int $0x13 # from disk
|
||||
popl %ebx # Restore
|
||||
pop %bx # Restore
|
||||
jnc read.4 # If success
|
||||
decl %edi # Retry?
|
||||
dec %di # Retry?
|
||||
jz read.6 # No
|
||||
xorb %ah,%ah # BIOS: Reset
|
||||
int $0x13 # disk system
|
||||
xchgl %ebx,%eax # Block count
|
||||
xchg %bx,%ax # Block count
|
||||
jmp read.3 # Continue
|
||||
read.4: movzbl %bl,%eax # Sectors read
|
||||
addwr1(_ax,0x8,_bp_) # Adjust
|
||||
read.4: movzbw %bl,%ax # Sectors read
|
||||
add %ax,0x8(%bp) # Adjust
|
||||
jnc read.5 # LBA,
|
||||
incw1(0xa,_bp_) # transfer
|
||||
incw 0xa(%bp) # transfer
|
||||
read.5: shlb %bl # buffer
|
||||
addbr1(_bl,0x5,_bp_) # pointer,
|
||||
subbr1(_al,0x2,_bp_) # block count
|
||||
add %bl,0x5(%bp) # pointer,
|
||||
sub %al,0x2(%bp) # block count
|
||||
ja read.1 # If not done
|
||||
read.6: ret # To caller
|
||||
read.6: retw # To caller
|
||||
|
||||
# Messages
|
||||
|
||||
|
||||
@ -19,8 +19,8 @@ btx: btx.o
|
||||
objcopy -S -O binary btx.out ${.TARGET}
|
||||
.endif
|
||||
|
||||
btx.o: btx.m4 btx.s
|
||||
(cd ${.CURDIR}; ${M4} ${M4FLAGS} btx.m4 btx.s) | \
|
||||
btx.o: btx.s
|
||||
(cd ${.CURDIR}; ${M4} ${M4FLAGS} btx.s) | \
|
||||
${AS} ${AFLAGS} -o ${.TARGET}
|
||||
|
||||
CLEANFILES+= btx btx.out btx.o
|
||||
|
||||
@ -94,6 +94,7 @@
|
||||
# Code segment.
|
||||
#
|
||||
.globl start
|
||||
.code16
|
||||
start: # Start of code
|
||||
#
|
||||
# BTX header.
|
||||
@ -111,116 +112,115 @@ btx_hdr: .byte 0xeb # Machine ID
|
||||
# Initialization routine.
|
||||
#
|
||||
init: cli # Disable interrupts
|
||||
xorl %eax,%eax # Zero/segment
|
||||
movl %ax,%ss # Set up
|
||||
movwir(MEM_ESP0,_sp) # stack
|
||||
movl %ax,%es # Address
|
||||
movl %ax,%ds # data
|
||||
pushw $0x2 # Clear
|
||||
popfw # flags
|
||||
xor %ax,%ax # Zero/segment
|
||||
mov %ax,%ss # Set up
|
||||
mov $MEM_ESP0,%sp # stack
|
||||
mov %ax,%es # Address
|
||||
mov %ax,%ds # data
|
||||
pushl $0x2 # Clear
|
||||
popfl # flags
|
||||
#
|
||||
# Initialize memory.
|
||||
#
|
||||
movwir(MEM_IDT,_di) # Memory to initialize
|
||||
movwir((MEM_ORG-MEM_IDT)/2,_cx) # Words to zero
|
||||
pushl %edi # Save
|
||||
mov $MEM_IDT,%di # Memory to initialize
|
||||
mov $(MEM_ORG-MEM_IDT)/2,%cx # Words to zero
|
||||
push %di # Save
|
||||
rep # Zero-fill
|
||||
stosl # memory
|
||||
popl %edi # Restore
|
||||
stosw # memory
|
||||
pop %di # Restore
|
||||
#
|
||||
# Create IDT.
|
||||
#
|
||||
movwir(idtctl,_si) # Control string
|
||||
mov $idtctl,%si # Control string
|
||||
init.1: lodsb # Get entry
|
||||
cwde # count
|
||||
xchgl %eax,%ecx # as word
|
||||
jecxz init.4 # If done
|
||||
cbw # count
|
||||
xchg %ax,%cx # as word
|
||||
jcxz init.4 # If done
|
||||
lodsb # Get segment
|
||||
xchgl %eax,%edx # P:DPL:type
|
||||
lodsl # Get control
|
||||
xchgl %eax,%ebx # set
|
||||
lodsl # Get handler offset
|
||||
movb $SEL_SCODE,%dh # Segment selector
|
||||
init.2: shrl %ebx # Handle this int?
|
||||
xchg %ax,%dx # P:DPL:type
|
||||
lodsw # Get control
|
||||
xchg %ax,%bx # set
|
||||
lodsw # Get handler offset
|
||||
mov $SEL_SCODE,%dh # Segment selector
|
||||
init.2: shr %bx # Handle this int?
|
||||
jnc init.3 # No
|
||||
movwr0(_ax,_di_) # Set handler offset
|
||||
movbr1(_dh,0x2,_di_) # and selector
|
||||
movbr1(_dl,0x5,_di_) # Set P:DPL:type
|
||||
addwia(0x4) # Next handler
|
||||
init.3: leaw1r(0x8,_di_,_di) # Next entry
|
||||
mov %ax,(%di) # Set handler offset
|
||||
mov %dh,0x2(%di) # and selector
|
||||
mov %dl,0x5(%di) # Set P:DPL:type
|
||||
add $0x4,%ax # Next handler
|
||||
init.3: lea 0x8(%di),%di # Next entry
|
||||
loop init.2 # Till set done
|
||||
jmp init.1 # Continue
|
||||
#
|
||||
# Initialize TSS.
|
||||
#
|
||||
init.4: movbi1(_ESP0H,TSS_ESP0+1,_di_) # Set ESP0
|
||||
movbi1(SEL_SDATA,TSS_SS0,_di_) # Set SS0
|
||||
movbi1(_ESP1H,TSS_ESP1+1,_di_) # Set ESP1
|
||||
movbi1(_TSSIO,TSS_MAP,_di_) # Set I/O bit map base
|
||||
init.4: movb $_ESP0H,TSS_ESP0+1(%di) # Set ESP0
|
||||
movb $SEL_SDATA,TSS_SS0(%di) # Set SS0
|
||||
movb $_ESP1H,TSS_ESP1+1(%di) # Set ESP1
|
||||
movb $_TSSIO,TSS_MAP(%di) # Set I/O bit map base
|
||||
ifdef(`PAGING',`
|
||||
#
|
||||
# Create page directory.
|
||||
#
|
||||
xorw %dx,%dx # Page
|
||||
movb $PAG_SIZ>>0x8,%dh # size
|
||||
xorw %ax,%ax # Zero
|
||||
movwir(MEM_DIR,_di) # Page directory
|
||||
movb $PAG_CNT>>0xa,%cl # Entries
|
||||
movwir(MEM_TBL|0x7,_ax) # First entry
|
||||
init.5: stosw # Write entry
|
||||
addl %edx,%eax # To next
|
||||
xor %edx,%edx # Page
|
||||
mov $PAG_SIZ>>0x8,%dh # size
|
||||
xor %eax,%eax # Zero
|
||||
mov $MEM_DIR,%di # Page directory
|
||||
mov $PAG_CNT>>0xa,%cl # Entries
|
||||
mov $MEM_TBL|0x7,%ax # First entry
|
||||
init.5: stosl # Write entry
|
||||
add %dx,%ax # To next
|
||||
loop init.5 # Till done
|
||||
#
|
||||
# Create page tables.
|
||||
#
|
||||
movwir(MEM_TBL,_di) # Page table
|
||||
movb $PAG_CNT>>0x8,%ch # Entries
|
||||
xorl %eax,%eax # Start address
|
||||
init.6: movb $0x7,%al # Set U:W:P flags
|
||||
cmpwmr(btx_hdr+0x8,_cx) # Standard user page?
|
||||
mov $MEM_TBL,%di # Page table
|
||||
mov $PAG_CNT>>0x8,%ch # Entries
|
||||
xor %ax,%ax # Start address
|
||||
init.6: mov $0x7,%al # Set U:W:P flags
|
||||
cmp btx_hdr+0x8,%cx # Standard user page?
|
||||
jb init.7 # Yes
|
||||
cmpwir(PAG_CNT-MEM_BTX>>0xc,_cx)# BTX memory?
|
||||
cmp $PAG_CNT-MEM_BTX>>0xc,%cx # BTX memory?
|
||||
jae init.7 # No or first page
|
||||
andb $~0x2,%al # Clear W flag
|
||||
cmpwir(PAG_CNT-MEM_USR>>0xc,_cx)# User page zero?
|
||||
and $~0x2,%al # Clear W flag
|
||||
cmp $PAG_CNT-MEM_USR>>0xc,%cx # User page zero?
|
||||
jne init.7 # No
|
||||
tstbim(0x80,btx_hdr+0x7) # Unmap it?
|
||||
testb $0x80,btx_hdr+0x7 # Unmap it?
|
||||
jz init.7 # No
|
||||
andb $~0x1,%al # Clear P flag
|
||||
init.7: stosw # Set entry
|
||||
addw %dx,%ax # Next address
|
||||
and $~0x1,%al # Clear P flag
|
||||
init.7: stosl # Set entry
|
||||
add %edx,%eax # Next address
|
||||
loop init.6 # Till done
|
||||
')
|
||||
#
|
||||
# Bring up the system.
|
||||
#
|
||||
movwir(0x2820,_bx) # Set protected mode
|
||||
callwi(setpic) # IRQ offsets
|
||||
lidtwm(idtdesc) # Set IDT
|
||||
mov $0x2820,%bx # Set protected mode
|
||||
callw setpic # IRQ offsets
|
||||
lidt idtdesc # Set IDT
|
||||
ifdef(`PAGING',`
|
||||
xorw %ax,%ax # Set base
|
||||
movb $MEM_DIR>>0x8,%ah # of page
|
||||
movl %eax,%cr3 # directory
|
||||
xor %eax,%eax # Set base
|
||||
mov $MEM_DIR>>0x8,%ah # of page
|
||||
mov %eax,%cr3 # directory
|
||||
')
|
||||
lgdtwm(gdtdesc) # Set GDT
|
||||
movl %cr0,%eax # Switch to
|
||||
lgdt gdtdesc # Set GDT
|
||||
mov %cr0,%eax # Switch to protected
|
||||
ifdef(`PAGING',`
|
||||
o16 # protected mode
|
||||
orl $0x80000001,%eax # and enable paging
|
||||
or $0x80000001,%eax # mode and enable paging
|
||||
',`
|
||||
o16 # protected mode
|
||||
orl $0x01,%eax #
|
||||
or $0x01,%eax # mode
|
||||
')
|
||||
movl %eax,%cr0 #
|
||||
jmpfwi(SEL_SCODE,init.8) # To 32-bit code
|
||||
mov %eax,%cr0 #
|
||||
ljmp $SEL_SCODE,$init.8 # To 32-bit code
|
||||
.code32
|
||||
init.8: xorl %ecx,%ecx # Zero
|
||||
movb $SEL_SDATA,%cl # To 32-bit
|
||||
movl %cx,%ss # stack
|
||||
movw %cx,%ss # stack
|
||||
#
|
||||
# Launch user task.
|
||||
#
|
||||
movb $SEL_TSS,%cl # Set task
|
||||
ltrl %ecx # register
|
||||
ltr %cx # register
|
||||
movl $MEM_USR,%edx # User base address
|
||||
movzwl %ss:BDA_MEM,%eax # Get free memory
|
||||
shll $0xa,%eax # To bytes
|
||||
@ -229,8 +229,8 @@ init.8: xorl %ecx,%ecx # Zero
|
||||
movb $SEL_UDATA,%cl # User data selector
|
||||
pushl %ecx # Set SS
|
||||
pushl %eax # Set ESP
|
||||
pushl $0x202 # Set flags (IF set)
|
||||
pushl $SEL_UCODE # Set CS
|
||||
push $0x202 # Set flags (IF set)
|
||||
push $SEL_UCODE # Set CS
|
||||
pushl btx_hdr+0xc # Set EIP
|
||||
pushl %ecx # Set GS
|
||||
pushl %ecx # Set FS
|
||||
@ -238,7 +238,7 @@ init.8: xorl %ecx,%ecx # Zero
|
||||
pushl %ecx # Set ES
|
||||
pushl %edx # Set EAX
|
||||
movb $0x7,%cl # Set remaining
|
||||
init.9: pushb $0x0 # general
|
||||
init.9: push $0x0 # general
|
||||
loop init.9 # registers
|
||||
popa # and initialize
|
||||
popl %es # Initialize
|
||||
@ -266,43 +266,41 @@ ifdef(`PAGING',`
|
||||
#
|
||||
# To 16 bits.
|
||||
#
|
||||
o16 # Reload
|
||||
jmpfwi(SEL_RCODE,exit.1) # CS
|
||||
exit.1: movb $SEL_RDATA,%cl # 16-bit selector
|
||||
movl %cx,%ss # Reload SS
|
||||
movl %cx,%ds # Load
|
||||
movl %cx,%es # remaining
|
||||
movl %cx,%fs # segment
|
||||
movl %cx,%gs # registers
|
||||
ljmpw $SEL_RCODE,$exit.1 # Reload CS
|
||||
.code16
|
||||
exit.1: mov $SEL_RDATA,%cl # 16-bit selector
|
||||
mov %cx,%ss # Reload SS
|
||||
mov %cx,%ds # Load
|
||||
mov %cx,%es # remaining
|
||||
mov %cx,%fs # segment
|
||||
mov %cx,%gs # registers
|
||||
#
|
||||
# To real-address mode.
|
||||
#
|
||||
decl %eax # Switch to
|
||||
movl %eax,%cr0 # real mode
|
||||
jmpfwi(0x0,exit.2) # Reload CS
|
||||
exit.2: xorl %eax,%eax # Real mode segment
|
||||
movl %ax,%ss # Reload SS
|
||||
movl %ax,%ds # Address data
|
||||
movwir(0x7008,_bx) # Set real mode
|
||||
callwi(setpic) # IRQ offsets
|
||||
lidtwm(ivtdesc) # Set IVT
|
||||
dec %ax # Switch to
|
||||
mov %eax,%cr0 # real mode
|
||||
ljmp $0x0,$exit.2 # Reload CS
|
||||
exit.2: xor %ax,%ax # Real mode segment
|
||||
mov %ax,%ss # Reload SS
|
||||
mov %ax,%ds # Address data
|
||||
mov $0x7008,%bx # Set real mode
|
||||
callw setpic # IRQ offsets
|
||||
lidt ivtdesc # Set IVT
|
||||
#
|
||||
# Reboot or await reset.
|
||||
#
|
||||
sti # Enable interrupts
|
||||
tstbim(0x1,btx_hdr+0x7) # Reboot?
|
||||
testb $0x1,btx_hdr+0x7 # Reboot?
|
||||
exit.3: jz exit.3 # No
|
||||
.code16
|
||||
movw $0x1234, BDA_BOOT # Do a warm boot
|
||||
jmpfwi(0xffff,0x0) # reboot the machine
|
||||
.code32
|
||||
ljmp $0xffff,$0x0 # reboot the machine
|
||||
#
|
||||
# Set IRQ offsets by reprogramming 8259A PICs.
|
||||
#
|
||||
setpic: inb $0x21,%al # Save master
|
||||
pushl %eax # IMR
|
||||
inb $0xa1,%al # Save slave
|
||||
pushl %eax # IMR
|
||||
setpic: in $0x21,%al # Save master
|
||||
push %ax # IMR
|
||||
in $0xa1,%al # Save slave
|
||||
push %ax # IMR
|
||||
movb $0x11,%al # ICW1 to
|
||||
outb %al,$0x20 # master,
|
||||
outb %al,$0xa0 # slave
|
||||
@ -317,11 +315,12 @@ setpic: inb $0x21,%al # Save master
|
||||
movb $0x1,%al # ICW4 to
|
||||
outb %al,$0x21 # master,
|
||||
outb %al,$0xa1 # slave
|
||||
popl %eax # Restore slave
|
||||
pop %ax # Restore slave
|
||||
outb %al,$0xa1 # IMR
|
||||
popl %eax # Restore master
|
||||
pop %ax # Restore master
|
||||
outb %al,$0x21 # IMR
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
.code32
|
||||
#
|
||||
# Initiate return from V86 mode to user mode.
|
||||
#
|
||||
@ -329,33 +328,33 @@ inthlt: hlt # To supervisor mode
|
||||
#
|
||||
# Exception jump table.
|
||||
#
|
||||
intx00: pushb $0x0 # Int 0x0: #DE
|
||||
intx00: push $0x0 # Int 0x0: #DE
|
||||
jmp ex_noc # Divide error
|
||||
pushb $0x1 # Int 0x1: #DB
|
||||
push $0x1 # Int 0x1: #DB
|
||||
jmp ex_noc # Debug
|
||||
pushb $0x3 # Int 0x3: #BP
|
||||
push $0x3 # Int 0x3: #BP
|
||||
jmp ex_noc # Breakpoint
|
||||
pushb $0x4 # Int 0x4: #OF
|
||||
push $0x4 # Int 0x4: #OF
|
||||
jmp ex_noc # Overflow
|
||||
pushb $0x5 # Int 0x5: #BR
|
||||
push $0x5 # Int 0x5: #BR
|
||||
jmp ex_noc # BOUND range exceeded
|
||||
pushb $0x6 # Int 0x6: #UD
|
||||
push $0x6 # Int 0x6: #UD
|
||||
jmp ex_noc # Invalid opcode
|
||||
pushb $0x7 # Int 0x7: #NM
|
||||
push $0x7 # Int 0x7: #NM
|
||||
jmp ex_noc # Device not available
|
||||
pushb $0x8 # Int 0x8: #DF
|
||||
push $0x8 # Int 0x8: #DF
|
||||
jmp except # Double fault
|
||||
pushb $0xa # Int 0xa: #TS
|
||||
push $0xa # Int 0xa: #TS
|
||||
jmp except # Invalid TSS
|
||||
pushb $0xb # Int 0xb: #NP
|
||||
push $0xb # Int 0xb: #NP
|
||||
jmp except # Segment not present
|
||||
pushb $0xc # Int 0xc: #SS
|
||||
push $0xc # Int 0xc: #SS
|
||||
jmp except # Stack segment fault
|
||||
pushb $0xd # Int 0xd: #GP
|
||||
push $0xd # Int 0xd: #GP
|
||||
jmp ex_v86 # General protection
|
||||
pushb $0xe # Int 0xe: #PF
|
||||
push $0xe # Int 0xe: #PF
|
||||
jmp except # Page fault
|
||||
intx10: pushb $0x10 # Int 0x10: #MF
|
||||
intx10: push $0x10 # Int 0x10: #MF
|
||||
jmp ex_noc # Floating-point error
|
||||
#
|
||||
# Handle #GP exception.
|
||||
@ -392,7 +391,7 @@ except: cld # String ops inc
|
||||
except.1: pushl 0x50(%esp,1) # Set GS, FS, DS, ES
|
||||
decb %al # (if V86 mode), and
|
||||
jne except.1 # SS, ESP
|
||||
except.2: pushl $SEL_SDATA # Set up
|
||||
except.2: push $SEL_SDATA # Set up
|
||||
popl %ds # to
|
||||
pushl %ds # address
|
||||
popl %es # data
|
||||
@ -538,7 +537,7 @@ v86sti: orb $0x2,0x31(%ebp) # Set IF
|
||||
v86pushf: subl %ecx,%ebx # Adjust SP
|
||||
cmpb $0x4,%cl # 32-bit
|
||||
je v86pushf.1 # Yes
|
||||
o16 # 16-bit
|
||||
data16 # 16-bit
|
||||
v86pushf.1: movl %edx,(%ebx) # Save flags
|
||||
jmp v86mon.6 # Finish up
|
||||
#
|
||||
@ -555,7 +554,7 @@ v86iret: movzwl (%ebx),%esi # Load V86 IP
|
||||
v86popf: cmpb $0x4,%cl # 32-bit?
|
||||
je v86popf.1 # Yes
|
||||
movl %edx,%eax # Initialize
|
||||
o16 # 16-bit
|
||||
data16 # 16-bit
|
||||
v86popf.1: movl (%ebx),%eax # Load flags
|
||||
addl %ecx,%ebx # Adjust SP
|
||||
andl $V86_FLG,%eax # Merge
|
||||
@ -654,37 +653,37 @@ v86intn.3: subl %edi,%esi # From
|
||||
#
|
||||
# Hardware interrupt jump table.
|
||||
#
|
||||
intx20: pushb $0x8 # Int 0x20: IRQ0
|
||||
intx20: push $0x8 # Int 0x20: IRQ0
|
||||
jmp int_hw # V86 int 0x8
|
||||
pushb $0x9 # Int 0x21: IRQ1
|
||||
push $0x9 # Int 0x21: IRQ1
|
||||
jmp int_hw # V86 int 0x9
|
||||
pushb $0xa # Int 0x22: IRQ2
|
||||
push $0xa # Int 0x22: IRQ2
|
||||
jmp int_hw # V86 int 0xa
|
||||
pushb $0xb # Int 0x23: IRQ3
|
||||
push $0xb # Int 0x23: IRQ3
|
||||
jmp int_hw # V86 int 0xb
|
||||
pushb $0xc # Int 0x24: IRQ4
|
||||
push $0xc # Int 0x24: IRQ4
|
||||
jmp int_hw # V86 int 0xc
|
||||
pushb $0xd # Int 0x25: IRQ5
|
||||
push $0xd # Int 0x25: IRQ5
|
||||
jmp int_hw # V86 int 0xd
|
||||
pushb $0xe # Int 0x26: IRQ6
|
||||
push $0xe # Int 0x26: IRQ6
|
||||
jmp int_hw # V86 int 0xe
|
||||
pushb $0xf # Int 0x27: IRQ7
|
||||
push $0xf # Int 0x27: IRQ7
|
||||
jmp int_hw # V86 int 0xf
|
||||
pushb $0x70 # Int 0x28: IRQ8
|
||||
push $0x70 # Int 0x28: IRQ8
|
||||
jmp int_hw # V86 int 0x70
|
||||
pushb $0x71 # Int 0x29: IRQ9
|
||||
push $0x71 # Int 0x29: IRQ9
|
||||
jmp int_hw # V86 int 0x71
|
||||
pushb $0x72 # Int 0x2a: IRQ10
|
||||
push $0x72 # Int 0x2a: IRQ10
|
||||
jmp int_hw # V86 int 0x72
|
||||
pushb $0x73 # Int 0x2b: IRQ11
|
||||
push $0x73 # Int 0x2b: IRQ11
|
||||
jmp int_hw # V86 int 0x73
|
||||
pushb $0x74 # Int 0x2c: IRQ12
|
||||
push $0x74 # Int 0x2c: IRQ12
|
||||
jmp int_hw # V86 int 0x74
|
||||
pushb $0x75 # Int 0x2d: IRQ13
|
||||
push $0x75 # Int 0x2d: IRQ13
|
||||
jmp int_hw # V86 int 0x75
|
||||
pushb $0x76 # Int 0x2e: IRQ14
|
||||
push $0x76 # Int 0x2e: IRQ14
|
||||
jmp int_hw # V86 int 0x76
|
||||
pushb $0x77 # Int 0x2f: IRQ15
|
||||
push $0x77 # Int 0x2f: IRQ15
|
||||
jmp int_hw # V86 int 0x77
|
||||
#
|
||||
# Reflect hardware interrupts.
|
||||
@ -733,7 +732,7 @@ intusr: std # String ops dec
|
||||
pushl %fs # and
|
||||
pushl %ds # point
|
||||
pushl %es # to them
|
||||
pushb $SEL_SDATA # Set up
|
||||
push $SEL_SDATA # Set up
|
||||
popl %ds # to
|
||||
pushl %ds # address
|
||||
popl %es # data
|
||||
@ -863,7 +862,7 @@ dump.2: testb $DMP_MEM,%ch # Dump memory?
|
||||
pushl %ds # Save
|
||||
testb $0x2,0x52(%ebx) # V86 mode?
|
||||
jnz dump.3 # Yes
|
||||
verrl 0x4(%esi) # Readable selector?
|
||||
verr 0x4(%esi) # Readable selector?
|
||||
jnz dump.3 # No
|
||||
ldsl (%esi),%esi # Load pointer
|
||||
jmp dump.4 # Join common code
|
||||
|
||||
@ -1,59 +0,0 @@
|
||||
#
|
||||
# Copyright (c) 1998 Robert Nordier
|
||||
# All rights reserved.
|
||||
#
|
||||
# Redistribution and use in source and binary forms are freely
|
||||
# permitted provided that the above copyright notice and this
|
||||
# paragraph and the following disclaimer are duplicated in all
|
||||
# such forms.
|
||||
#
|
||||
# This software is provided "AS IS" and without any express or
|
||||
# implied warranties, including, without limitation, the implied
|
||||
# warranties of merchantability and fitness for a particular
|
||||
# purpose.
|
||||
#
|
||||
|
||||
# $FreeBSD$
|
||||
|
||||
define(_al,0x0)dnl
|
||||
define(_cl,0x1)dnl
|
||||
define(_dl,0x2)dnl
|
||||
define(_bl,0x3)dnl
|
||||
define(_ah,0x4)dnl
|
||||
define(_ch,0x5)dnl
|
||||
define(_dh,0x6)dnl
|
||||
define(_bh,0x7)dnl
|
||||
|
||||
define(_ax,0x0)dnl
|
||||
define(_cx,0x1)dnl
|
||||
define(_dx,0x2)dnl
|
||||
define(_bx,0x3)dnl
|
||||
define(_sp,0x4)dnl
|
||||
define(_bp,0x5)dnl
|
||||
define(_si,0x6)dnl
|
||||
define(_di,0x7)dnl
|
||||
|
||||
define(_bx_si,0x0)dnl
|
||||
define(_bx_di,0x1)dnl
|
||||
define(_bp_si,0x2)dnl
|
||||
define(_bp_di,0x3)dnl
|
||||
define(_si_,0x4)dnl
|
||||
define(_di_,0x5)dnl
|
||||
define(_bp_,0x6)dnl
|
||||
define(_bx_,0x7)dnl
|
||||
|
||||
define(o16,`.byte 0x66')dnl
|
||||
|
||||
define(addwia,`.byte 0x5; .word $1')dnl
|
||||
define(lgdtwm,`.byte 0xf; .byte 0x1; .byte 0x16; .word $1')dnl
|
||||
define(lidtwm,`.byte 0xf; .byte 0x1; .byte 0x1e; .word $1')dnl
|
||||
define(cmpwmr,`.byte 0x3b; .byte ($2 << 0x3) | 0x6; .word $1')dnl
|
||||
define(cmpwir,`.byte 0x81; .byte 0xf8 | $2; .word $1')dnl
|
||||
define(movbr1,`.byte 0x88; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
|
||||
define(movwr0,`.byte 0x89; .byte ($1 << 0x3) | $2')dnl
|
||||
define(leaw1r,`.byte 0x8d; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
|
||||
define(movwir,`.byte 0xb8 | $2; .word $1')dnl
|
||||
define(movbi1,`.byte 0xc6; .byte 0x40 | $3; .byte $2; .byte $1')dnl
|
||||
define(callwi,`.byte 0xe8; .word $1 - . - 0x2')dnl
|
||||
define(jmpfwi,`.byte 0xea; .word $2; .word $1')dnl
|
||||
define(tstbim,`.byte 0xf6; .byte 0x6; .word $2; .byte $1')dnl
|
||||
@ -94,6 +94,7 @@
|
||||
# Code segment.
|
||||
#
|
||||
.globl start
|
||||
.code16
|
||||
start: # Start of code
|
||||
#
|
||||
# BTX header.
|
||||
@ -111,116 +112,115 @@ btx_hdr: .byte 0xeb # Machine ID
|
||||
# Initialization routine.
|
||||
#
|
||||
init: cli # Disable interrupts
|
||||
xorl %eax,%eax # Zero/segment
|
||||
movl %ax,%ss # Set up
|
||||
movwir(MEM_ESP0,_sp) # stack
|
||||
movl %ax,%es # Address
|
||||
movl %ax,%ds # data
|
||||
pushw $0x2 # Clear
|
||||
popfw # flags
|
||||
xor %ax,%ax # Zero/segment
|
||||
mov %ax,%ss # Set up
|
||||
mov $MEM_ESP0,%sp # stack
|
||||
mov %ax,%es # Address
|
||||
mov %ax,%ds # data
|
||||
pushl $0x2 # Clear
|
||||
popfl # flags
|
||||
#
|
||||
# Initialize memory.
|
||||
#
|
||||
movwir(MEM_IDT,_di) # Memory to initialize
|
||||
movwir((MEM_ORG-MEM_IDT)/2,_cx) # Words to zero
|
||||
pushl %edi # Save
|
||||
mov $MEM_IDT,%di # Memory to initialize
|
||||
mov $(MEM_ORG-MEM_IDT)/2,%cx # Words to zero
|
||||
push %di # Save
|
||||
rep # Zero-fill
|
||||
stosl # memory
|
||||
popl %edi # Restore
|
||||
stosw # memory
|
||||
pop %di # Restore
|
||||
#
|
||||
# Create IDT.
|
||||
#
|
||||
movwir(idtctl,_si) # Control string
|
||||
mov $idtctl,%si # Control string
|
||||
init.1: lodsb # Get entry
|
||||
cwde # count
|
||||
xchgl %eax,%ecx # as word
|
||||
jecxz init.4 # If done
|
||||
cbw # count
|
||||
xchg %ax,%cx # as word
|
||||
jcxz init.4 # If done
|
||||
lodsb # Get segment
|
||||
xchgl %eax,%edx # P:DPL:type
|
||||
lodsl # Get control
|
||||
xchgl %eax,%ebx # set
|
||||
lodsl # Get handler offset
|
||||
movb $SEL_SCODE,%dh # Segment selector
|
||||
init.2: shrl %ebx # Handle this int?
|
||||
xchg %ax,%dx # P:DPL:type
|
||||
lodsw # Get control
|
||||
xchg %ax,%bx # set
|
||||
lodsw # Get handler offset
|
||||
mov $SEL_SCODE,%dh # Segment selector
|
||||
init.2: shr %bx # Handle this int?
|
||||
jnc init.3 # No
|
||||
movwr0(_ax,_di_) # Set handler offset
|
||||
movbr1(_dh,0x2,_di_) # and selector
|
||||
movbr1(_dl,0x5,_di_) # Set P:DPL:type
|
||||
addwia(0x4) # Next handler
|
||||
init.3: leaw1r(0x8,_di_,_di) # Next entry
|
||||
mov %ax,(%di) # Set handler offset
|
||||
mov %dh,0x2(%di) # and selector
|
||||
mov %dl,0x5(%di) # Set P:DPL:type
|
||||
add $0x4,%ax # Next handler
|
||||
init.3: lea 0x8(%di),%di # Next entry
|
||||
loop init.2 # Till set done
|
||||
jmp init.1 # Continue
|
||||
#
|
||||
# Initialize TSS.
|
||||
#
|
||||
init.4: movbi1(_ESP0H,TSS_ESP0+1,_di_) # Set ESP0
|
||||
movbi1(SEL_SDATA,TSS_SS0,_di_) # Set SS0
|
||||
movbi1(_ESP1H,TSS_ESP1+1,_di_) # Set ESP1
|
||||
movbi1(_TSSIO,TSS_MAP,_di_) # Set I/O bit map base
|
||||
init.4: movb $_ESP0H,TSS_ESP0+1(%di) # Set ESP0
|
||||
movb $SEL_SDATA,TSS_SS0(%di) # Set SS0
|
||||
movb $_ESP1H,TSS_ESP1+1(%di) # Set ESP1
|
||||
movb $_TSSIO,TSS_MAP(%di) # Set I/O bit map base
|
||||
ifdef(`PAGING',`
|
||||
#
|
||||
# Create page directory.
|
||||
#
|
||||
xorw %dx,%dx # Page
|
||||
movb $PAG_SIZ>>0x8,%dh # size
|
||||
xorw %ax,%ax # Zero
|
||||
movwir(MEM_DIR,_di) # Page directory
|
||||
movb $PAG_CNT>>0xa,%cl # Entries
|
||||
movwir(MEM_TBL|0x7,_ax) # First entry
|
||||
init.5: stosw # Write entry
|
||||
addl %edx,%eax # To next
|
||||
xor %edx,%edx # Page
|
||||
mov $PAG_SIZ>>0x8,%dh # size
|
||||
xor %eax,%eax # Zero
|
||||
mov $MEM_DIR,%di # Page directory
|
||||
mov $PAG_CNT>>0xa,%cl # Entries
|
||||
mov $MEM_TBL|0x7,%ax # First entry
|
||||
init.5: stosl # Write entry
|
||||
add %dx,%ax # To next
|
||||
loop init.5 # Till done
|
||||
#
|
||||
# Create page tables.
|
||||
#
|
||||
movwir(MEM_TBL,_di) # Page table
|
||||
movb $PAG_CNT>>0x8,%ch # Entries
|
||||
xorl %eax,%eax # Start address
|
||||
init.6: movb $0x7,%al # Set U:W:P flags
|
||||
cmpwmr(btx_hdr+0x8,_cx) # Standard user page?
|
||||
mov $MEM_TBL,%di # Page table
|
||||
mov $PAG_CNT>>0x8,%ch # Entries
|
||||
xor %ax,%ax # Start address
|
||||
init.6: mov $0x7,%al # Set U:W:P flags
|
||||
cmp btx_hdr+0x8,%cx # Standard user page?
|
||||
jb init.7 # Yes
|
||||
cmpwir(PAG_CNT-MEM_BTX>>0xc,_cx)# BTX memory?
|
||||
cmp $PAG_CNT-MEM_BTX>>0xc,%cx # BTX memory?
|
||||
jae init.7 # No or first page
|
||||
andb $~0x2,%al # Clear W flag
|
||||
cmpwir(PAG_CNT-MEM_USR>>0xc,_cx)# User page zero?
|
||||
and $~0x2,%al # Clear W flag
|
||||
cmp $PAG_CNT-MEM_USR>>0xc,%cx # User page zero?
|
||||
jne init.7 # No
|
||||
tstbim(0x80,btx_hdr+0x7) # Unmap it?
|
||||
testb $0x80,btx_hdr+0x7 # Unmap it?
|
||||
jz init.7 # No
|
||||
andb $~0x1,%al # Clear P flag
|
||||
init.7: stosw # Set entry
|
||||
addw %dx,%ax # Next address
|
||||
and $~0x1,%al # Clear P flag
|
||||
init.7: stosl # Set entry
|
||||
add %edx,%eax # Next address
|
||||
loop init.6 # Till done
|
||||
')
|
||||
#
|
||||
# Bring up the system.
|
||||
#
|
||||
movwir(0x2820,_bx) # Set protected mode
|
||||
callwi(setpic) # IRQ offsets
|
||||
lidtwm(idtdesc) # Set IDT
|
||||
mov $0x2820,%bx # Set protected mode
|
||||
callw setpic # IRQ offsets
|
||||
lidt idtdesc # Set IDT
|
||||
ifdef(`PAGING',`
|
||||
xorw %ax,%ax # Set base
|
||||
movb $MEM_DIR>>0x8,%ah # of page
|
||||
movl %eax,%cr3 # directory
|
||||
xor %eax,%eax # Set base
|
||||
mov $MEM_DIR>>0x8,%ah # of page
|
||||
mov %eax,%cr3 # directory
|
||||
')
|
||||
lgdtwm(gdtdesc) # Set GDT
|
||||
movl %cr0,%eax # Switch to
|
||||
lgdt gdtdesc # Set GDT
|
||||
mov %cr0,%eax # Switch to protected
|
||||
ifdef(`PAGING',`
|
||||
o16 # protected mode
|
||||
orl $0x80000001,%eax # and enable paging
|
||||
or $0x80000001,%eax # mode and enable paging
|
||||
',`
|
||||
o16 # protected mode
|
||||
orl $0x01,%eax #
|
||||
or $0x01,%eax # mode
|
||||
')
|
||||
movl %eax,%cr0 #
|
||||
jmpfwi(SEL_SCODE,init.8) # To 32-bit code
|
||||
mov %eax,%cr0 #
|
||||
ljmp $SEL_SCODE,$init.8 # To 32-bit code
|
||||
.code32
|
||||
init.8: xorl %ecx,%ecx # Zero
|
||||
movb $SEL_SDATA,%cl # To 32-bit
|
||||
movl %cx,%ss # stack
|
||||
movw %cx,%ss # stack
|
||||
#
|
||||
# Launch user task.
|
||||
#
|
||||
movb $SEL_TSS,%cl # Set task
|
||||
ltrl %ecx # register
|
||||
ltr %cx # register
|
||||
movl $MEM_USR,%edx # User base address
|
||||
movzwl %ss:BDA_MEM,%eax # Get free memory
|
||||
shll $0xa,%eax # To bytes
|
||||
@ -229,8 +229,8 @@ init.8: xorl %ecx,%ecx # Zero
|
||||
movb $SEL_UDATA,%cl # User data selector
|
||||
pushl %ecx # Set SS
|
||||
pushl %eax # Set ESP
|
||||
pushl $0x202 # Set flags (IF set)
|
||||
pushl $SEL_UCODE # Set CS
|
||||
push $0x202 # Set flags (IF set)
|
||||
push $SEL_UCODE # Set CS
|
||||
pushl btx_hdr+0xc # Set EIP
|
||||
pushl %ecx # Set GS
|
||||
pushl %ecx # Set FS
|
||||
@ -238,7 +238,7 @@ init.8: xorl %ecx,%ecx # Zero
|
||||
pushl %ecx # Set ES
|
||||
pushl %edx # Set EAX
|
||||
movb $0x7,%cl # Set remaining
|
||||
init.9: pushb $0x0 # general
|
||||
init.9: push $0x0 # general
|
||||
loop init.9 # registers
|
||||
popa # and initialize
|
||||
popl %es # Initialize
|
||||
@ -266,43 +266,41 @@ ifdef(`PAGING',`
|
||||
#
|
||||
# To 16 bits.
|
||||
#
|
||||
o16 # Reload
|
||||
jmpfwi(SEL_RCODE,exit.1) # CS
|
||||
exit.1: movb $SEL_RDATA,%cl # 16-bit selector
|
||||
movl %cx,%ss # Reload SS
|
||||
movl %cx,%ds # Load
|
||||
movl %cx,%es # remaining
|
||||
movl %cx,%fs # segment
|
||||
movl %cx,%gs # registers
|
||||
ljmpw $SEL_RCODE,$exit.1 # Reload CS
|
||||
.code16
|
||||
exit.1: mov $SEL_RDATA,%cl # 16-bit selector
|
||||
mov %cx,%ss # Reload SS
|
||||
mov %cx,%ds # Load
|
||||
mov %cx,%es # remaining
|
||||
mov %cx,%fs # segment
|
||||
mov %cx,%gs # registers
|
||||
#
|
||||
# To real-address mode.
|
||||
#
|
||||
decl %eax # Switch to
|
||||
movl %eax,%cr0 # real mode
|
||||
jmpfwi(0x0,exit.2) # Reload CS
|
||||
exit.2: xorl %eax,%eax # Real mode segment
|
||||
movl %ax,%ss # Reload SS
|
||||
movl %ax,%ds # Address data
|
||||
movwir(0x7008,_bx) # Set real mode
|
||||
callwi(setpic) # IRQ offsets
|
||||
lidtwm(ivtdesc) # Set IVT
|
||||
dec %ax # Switch to
|
||||
mov %eax,%cr0 # real mode
|
||||
ljmp $0x0,$exit.2 # Reload CS
|
||||
exit.2: xor %ax,%ax # Real mode segment
|
||||
mov %ax,%ss # Reload SS
|
||||
mov %ax,%ds # Address data
|
||||
mov $0x7008,%bx # Set real mode
|
||||
callw setpic # IRQ offsets
|
||||
lidt ivtdesc # Set IVT
|
||||
#
|
||||
# Reboot or await reset.
|
||||
#
|
||||
sti # Enable interrupts
|
||||
tstbim(0x1,btx_hdr+0x7) # Reboot?
|
||||
testb $0x1,btx_hdr+0x7 # Reboot?
|
||||
exit.3: jz exit.3 # No
|
||||
.code16
|
||||
movw $0x1234, BDA_BOOT # Do a warm boot
|
||||
jmpfwi(0xffff,0x0) # reboot the machine
|
||||
.code32
|
||||
ljmp $0xffff,$0x0 # reboot the machine
|
||||
#
|
||||
# Set IRQ offsets by reprogramming 8259A PICs.
|
||||
#
|
||||
setpic: inb $0x21,%al # Save master
|
||||
pushl %eax # IMR
|
||||
inb $0xa1,%al # Save slave
|
||||
pushl %eax # IMR
|
||||
setpic: in $0x21,%al # Save master
|
||||
push %ax # IMR
|
||||
in $0xa1,%al # Save slave
|
||||
push %ax # IMR
|
||||
movb $0x11,%al # ICW1 to
|
||||
outb %al,$0x20 # master,
|
||||
outb %al,$0xa0 # slave
|
||||
@ -317,11 +315,12 @@ setpic: inb $0x21,%al # Save master
|
||||
movb $0x1,%al # ICW4 to
|
||||
outb %al,$0x21 # master,
|
||||
outb %al,$0xa1 # slave
|
||||
popl %eax # Restore slave
|
||||
pop %ax # Restore slave
|
||||
outb %al,$0xa1 # IMR
|
||||
popl %eax # Restore master
|
||||
pop %ax # Restore master
|
||||
outb %al,$0x21 # IMR
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
.code32
|
||||
#
|
||||
# Initiate return from V86 mode to user mode.
|
||||
#
|
||||
@ -329,33 +328,33 @@ inthlt: hlt # To supervisor mode
|
||||
#
|
||||
# Exception jump table.
|
||||
#
|
||||
intx00: pushb $0x0 # Int 0x0: #DE
|
||||
intx00: push $0x0 # Int 0x0: #DE
|
||||
jmp ex_noc # Divide error
|
||||
pushb $0x1 # Int 0x1: #DB
|
||||
push $0x1 # Int 0x1: #DB
|
||||
jmp ex_noc # Debug
|
||||
pushb $0x3 # Int 0x3: #BP
|
||||
push $0x3 # Int 0x3: #BP
|
||||
jmp ex_noc # Breakpoint
|
||||
pushb $0x4 # Int 0x4: #OF
|
||||
push $0x4 # Int 0x4: #OF
|
||||
jmp ex_noc # Overflow
|
||||
pushb $0x5 # Int 0x5: #BR
|
||||
push $0x5 # Int 0x5: #BR
|
||||
jmp ex_noc # BOUND range exceeded
|
||||
pushb $0x6 # Int 0x6: #UD
|
||||
push $0x6 # Int 0x6: #UD
|
||||
jmp ex_noc # Invalid opcode
|
||||
pushb $0x7 # Int 0x7: #NM
|
||||
push $0x7 # Int 0x7: #NM
|
||||
jmp ex_noc # Device not available
|
||||
pushb $0x8 # Int 0x8: #DF
|
||||
push $0x8 # Int 0x8: #DF
|
||||
jmp except # Double fault
|
||||
pushb $0xa # Int 0xa: #TS
|
||||
push $0xa # Int 0xa: #TS
|
||||
jmp except # Invalid TSS
|
||||
pushb $0xb # Int 0xb: #NP
|
||||
push $0xb # Int 0xb: #NP
|
||||
jmp except # Segment not present
|
||||
pushb $0xc # Int 0xc: #SS
|
||||
push $0xc # Int 0xc: #SS
|
||||
jmp except # Stack segment fault
|
||||
pushb $0xd # Int 0xd: #GP
|
||||
push $0xd # Int 0xd: #GP
|
||||
jmp ex_v86 # General protection
|
||||
pushb $0xe # Int 0xe: #PF
|
||||
push $0xe # Int 0xe: #PF
|
||||
jmp except # Page fault
|
||||
intx10: pushb $0x10 # Int 0x10: #MF
|
||||
intx10: push $0x10 # Int 0x10: #MF
|
||||
jmp ex_noc # Floating-point error
|
||||
#
|
||||
# Handle #GP exception.
|
||||
@ -392,7 +391,7 @@ except: cld # String ops inc
|
||||
except.1: pushl 0x50(%esp,1) # Set GS, FS, DS, ES
|
||||
decb %al # (if V86 mode), and
|
||||
jne except.1 # SS, ESP
|
||||
except.2: pushl $SEL_SDATA # Set up
|
||||
except.2: push $SEL_SDATA # Set up
|
||||
popl %ds # to
|
||||
pushl %ds # address
|
||||
popl %es # data
|
||||
@ -538,7 +537,7 @@ v86sti: orb $0x2,0x31(%ebp) # Set IF
|
||||
v86pushf: subl %ecx,%ebx # Adjust SP
|
||||
cmpb $0x4,%cl # 32-bit
|
||||
je v86pushf.1 # Yes
|
||||
o16 # 16-bit
|
||||
data16 # 16-bit
|
||||
v86pushf.1: movl %edx,(%ebx) # Save flags
|
||||
jmp v86mon.6 # Finish up
|
||||
#
|
||||
@ -555,7 +554,7 @@ v86iret: movzwl (%ebx),%esi # Load V86 IP
|
||||
v86popf: cmpb $0x4,%cl # 32-bit?
|
||||
je v86popf.1 # Yes
|
||||
movl %edx,%eax # Initialize
|
||||
o16 # 16-bit
|
||||
data16 # 16-bit
|
||||
v86popf.1: movl (%ebx),%eax # Load flags
|
||||
addl %ecx,%ebx # Adjust SP
|
||||
andl $V86_FLG,%eax # Merge
|
||||
@ -654,37 +653,37 @@ v86intn.3: subl %edi,%esi # From
|
||||
#
|
||||
# Hardware interrupt jump table.
|
||||
#
|
||||
intx20: pushb $0x8 # Int 0x20: IRQ0
|
||||
intx20: push $0x8 # Int 0x20: IRQ0
|
||||
jmp int_hw # V86 int 0x8
|
||||
pushb $0x9 # Int 0x21: IRQ1
|
||||
push $0x9 # Int 0x21: IRQ1
|
||||
jmp int_hw # V86 int 0x9
|
||||
pushb $0xa # Int 0x22: IRQ2
|
||||
push $0xa # Int 0x22: IRQ2
|
||||
jmp int_hw # V86 int 0xa
|
||||
pushb $0xb # Int 0x23: IRQ3
|
||||
push $0xb # Int 0x23: IRQ3
|
||||
jmp int_hw # V86 int 0xb
|
||||
pushb $0xc # Int 0x24: IRQ4
|
||||
push $0xc # Int 0x24: IRQ4
|
||||
jmp int_hw # V86 int 0xc
|
||||
pushb $0xd # Int 0x25: IRQ5
|
||||
push $0xd # Int 0x25: IRQ5
|
||||
jmp int_hw # V86 int 0xd
|
||||
pushb $0xe # Int 0x26: IRQ6
|
||||
push $0xe # Int 0x26: IRQ6
|
||||
jmp int_hw # V86 int 0xe
|
||||
pushb $0xf # Int 0x27: IRQ7
|
||||
push $0xf # Int 0x27: IRQ7
|
||||
jmp int_hw # V86 int 0xf
|
||||
pushb $0x70 # Int 0x28: IRQ8
|
||||
push $0x70 # Int 0x28: IRQ8
|
||||
jmp int_hw # V86 int 0x70
|
||||
pushb $0x71 # Int 0x29: IRQ9
|
||||
push $0x71 # Int 0x29: IRQ9
|
||||
jmp int_hw # V86 int 0x71
|
||||
pushb $0x72 # Int 0x2a: IRQ10
|
||||
push $0x72 # Int 0x2a: IRQ10
|
||||
jmp int_hw # V86 int 0x72
|
||||
pushb $0x73 # Int 0x2b: IRQ11
|
||||
push $0x73 # Int 0x2b: IRQ11
|
||||
jmp int_hw # V86 int 0x73
|
||||
pushb $0x74 # Int 0x2c: IRQ12
|
||||
push $0x74 # Int 0x2c: IRQ12
|
||||
jmp int_hw # V86 int 0x74
|
||||
pushb $0x75 # Int 0x2d: IRQ13
|
||||
push $0x75 # Int 0x2d: IRQ13
|
||||
jmp int_hw # V86 int 0x75
|
||||
pushb $0x76 # Int 0x2e: IRQ14
|
||||
push $0x76 # Int 0x2e: IRQ14
|
||||
jmp int_hw # V86 int 0x76
|
||||
pushb $0x77 # Int 0x2f: IRQ15
|
||||
push $0x77 # Int 0x2f: IRQ15
|
||||
jmp int_hw # V86 int 0x77
|
||||
#
|
||||
# Reflect hardware interrupts.
|
||||
@ -733,7 +732,7 @@ intusr: std # String ops dec
|
||||
pushl %fs # and
|
||||
pushl %ds # point
|
||||
pushl %es # to them
|
||||
pushb $SEL_SDATA # Set up
|
||||
push $SEL_SDATA # Set up
|
||||
popl %ds # to
|
||||
pushl %ds # address
|
||||
popl %es # data
|
||||
@ -863,7 +862,7 @@ dump.2: testb $DMP_MEM,%ch # Dump memory?
|
||||
pushl %ds # Save
|
||||
testb $0x2,0x52(%ebx) # V86 mode?
|
||||
jnz dump.3 # Yes
|
||||
verrl 0x4(%esi) # Readable selector?
|
||||
verr 0x4(%esi) # Readable selector?
|
||||
jnz dump.3 # No
|
||||
ldsl (%esi),%esi # Load pointer
|
||||
jmp dump.4 # Join common code
|
||||
|
||||
@ -81,13 +81,13 @@ start: cld # string ops inc
|
||||
movw %ax, %ds # setup the
|
||||
movw %ax, %es # data segments
|
||||
movw $welcome_msg, %si # %ds:(%si) -> welcome message
|
||||
call putstr # display the welcome message
|
||||
callw putstr # display the welcome message
|
||||
#
|
||||
# Setup the arguments that the loader is expecting from boot[12]
|
||||
#
|
||||
movw $bootinfo_msg, %si # %ds:(%si) -> boot args message
|
||||
call putstr # display the message
|
||||
movl $MEM_ARG, %ebx # %ds:(%ebx) -> boot args
|
||||
callw putstr # display the message
|
||||
movl $MEM_ARG, %bx # %ds:(%bx) -> boot args
|
||||
movw %bx, %di # %es:(%di) -> boot args
|
||||
xorl %eax, %eax # zero %eax
|
||||
movw $(MEM_ARG_SIZE/4), %cx # Size of arguments in 32-bit
|
||||
@ -95,18 +95,18 @@ start: cld # string ops inc
|
||||
rep # Clear the arguments
|
||||
stosl # to zero
|
||||
popw %dx # restore BIOS boot device
|
||||
movb %dl, 0x4(%ebx) # set kargs->bootdev
|
||||
orb $KARGS_FLAGS_CD, 0x8(%ebx) # kargs->bootflags |=
|
||||
movb %dl, 0x4(%bx) # set kargs->bootdev
|
||||
orb $KARGS_FLAGS_CD, 0x8(%bx) # kargs->bootflags |=
|
||||
# KARGS_FLAGS_CD
|
||||
#
|
||||
# Turn on the A20 address line
|
||||
#
|
||||
call seta20 # Turn A20 on
|
||||
callw seta20 # Turn A20 on
|
||||
#
|
||||
# Relocate the loader and BTX using a very lazy protected mode
|
||||
#
|
||||
movw $relocate_msg, %si # Display the
|
||||
call putstr # relocation message
|
||||
callw putstr # relocation message
|
||||
movl end+AOUT_ENTRY, %edi # %edi is the destination
|
||||
movl $(end+AOUT_HEADER), %esi # %esi is
|
||||
# the start of the text
|
||||
@ -118,9 +118,8 @@ start: cld # string ops inc
|
||||
movl %cr0, %eax # Turn on
|
||||
orb $0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # long jump to
|
||||
.word pm_start # clear the instruction
|
||||
.word SEL_SCODE # pre-fetch queue
|
||||
ljmp $SEL_SCODE,$pm_start # long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
.code32
|
||||
pm_start: movw $SEL_SDATA, %ax # Initialize
|
||||
movw %ax, %ds # %ds and
|
||||
@ -152,9 +151,8 @@ pm_16: movw $SEL_RDATA, %ax # Initialize
|
||||
movl %cr0, %eax # Turn off
|
||||
andb $~0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # Long jump to
|
||||
.word pm_end # clear the instruction
|
||||
.word 0x0 # pre-fetch
|
||||
ljmp $0,$pm_end # Long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
pm_end: sti # Turn interrupts back on now
|
||||
#
|
||||
# Copy the BTX client to MEM_BTX_CLIENT
|
||||
@ -185,10 +183,8 @@ pm_end: sti # Turn interrupts back on now
|
||||
# Now we just start up BTX and let it do the rest
|
||||
#
|
||||
movw $jump_message, %si # Display the
|
||||
call putstr # jump message
|
||||
.byte 0xea # Jump to
|
||||
.word MEM_BTX_ENTRY # BTX entry
|
||||
.word 0x0 # point
|
||||
callw putstr # jump message
|
||||
ljmp $0,$MEM_BTX_ENTRY # Jump to the BTX entry point
|
||||
|
||||
#
|
||||
# Display a null-terminated string
|
||||
@ -196,7 +192,7 @@ pm_end: sti # Turn interrupts back on now
|
||||
putstr: lodsb # load %al from %ds:(%si)
|
||||
testb %al,%al # stop at null
|
||||
jnz putc # if the char != null, output it
|
||||
ret # return when null is hit
|
||||
retw # return when null is hit
|
||||
putc: movw $0x7,%bx # attribute for output
|
||||
movb $0xe,%ah # BIOS: put_char
|
||||
int $0x10 # call BIOS, print char in %al
|
||||
@ -217,7 +213,7 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
#
|
||||
# BTX client to start btxldr
|
||||
|
||||
@ -81,13 +81,13 @@ start: cld # string ops inc
|
||||
movw %ax, %ds # setup the
|
||||
movw %ax, %es # data segments
|
||||
movw $welcome_msg, %si # %ds:(%si) -> welcome message
|
||||
call putstr # display the welcome message
|
||||
callw putstr # display the welcome message
|
||||
#
|
||||
# Setup the arguments that the loader is expecting from boot[12]
|
||||
#
|
||||
movw $bootinfo_msg, %si # %ds:(%si) -> boot args message
|
||||
call putstr # display the message
|
||||
movl $MEM_ARG, %ebx # %ds:(%ebx) -> boot args
|
||||
callw putstr # display the message
|
||||
movl $MEM_ARG, %bx # %ds:(%bx) -> boot args
|
||||
movw %bx, %di # %es:(%di) -> boot args
|
||||
xorl %eax, %eax # zero %eax
|
||||
movw $(MEM_ARG_SIZE/4), %cx # Size of arguments in 32-bit
|
||||
@ -95,18 +95,18 @@ start: cld # string ops inc
|
||||
rep # Clear the arguments
|
||||
stosl # to zero
|
||||
popw %dx # restore BIOS boot device
|
||||
movb %dl, 0x4(%ebx) # set kargs->bootdev
|
||||
orb $KARGS_FLAGS_CD, 0x8(%ebx) # kargs->bootflags |=
|
||||
movb %dl, 0x4(%bx) # set kargs->bootdev
|
||||
orb $KARGS_FLAGS_CD, 0x8(%bx) # kargs->bootflags |=
|
||||
# KARGS_FLAGS_CD
|
||||
#
|
||||
# Turn on the A20 address line
|
||||
#
|
||||
call seta20 # Turn A20 on
|
||||
callw seta20 # Turn A20 on
|
||||
#
|
||||
# Relocate the loader and BTX using a very lazy protected mode
|
||||
#
|
||||
movw $relocate_msg, %si # Display the
|
||||
call putstr # relocation message
|
||||
callw putstr # relocation message
|
||||
movl end+AOUT_ENTRY, %edi # %edi is the destination
|
||||
movl $(end+AOUT_HEADER), %esi # %esi is
|
||||
# the start of the text
|
||||
@ -118,9 +118,8 @@ start: cld # string ops inc
|
||||
movl %cr0, %eax # Turn on
|
||||
orb $0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # long jump to
|
||||
.word pm_start # clear the instruction
|
||||
.word SEL_SCODE # pre-fetch queue
|
||||
ljmp $SEL_SCODE,$pm_start # long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
.code32
|
||||
pm_start: movw $SEL_SDATA, %ax # Initialize
|
||||
movw %ax, %ds # %ds and
|
||||
@ -152,9 +151,8 @@ pm_16: movw $SEL_RDATA, %ax # Initialize
|
||||
movl %cr0, %eax # Turn off
|
||||
andb $~0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # Long jump to
|
||||
.word pm_end # clear the instruction
|
||||
.word 0x0 # pre-fetch
|
||||
ljmp $0,$pm_end # Long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
pm_end: sti # Turn interrupts back on now
|
||||
#
|
||||
# Copy the BTX client to MEM_BTX_CLIENT
|
||||
@ -185,10 +183,8 @@ pm_end: sti # Turn interrupts back on now
|
||||
# Now we just start up BTX and let it do the rest
|
||||
#
|
||||
movw $jump_message, %si # Display the
|
||||
call putstr # jump message
|
||||
.byte 0xea # Jump to
|
||||
.word MEM_BTX_ENTRY # BTX entry
|
||||
.word 0x0 # point
|
||||
callw putstr # jump message
|
||||
ljmp $0,$MEM_BTX_ENTRY # Jump to the BTX entry point
|
||||
|
||||
#
|
||||
# Display a null-terminated string
|
||||
@ -196,7 +192,7 @@ pm_end: sti # Turn interrupts back on now
|
||||
putstr: lodsb # load %al from %ds:(%si)
|
||||
testb %al,%al # stop at null
|
||||
jnz putc # if the char != null, output it
|
||||
ret # return when null is hit
|
||||
retw # return when null is hit
|
||||
putc: movw $0x7,%bx # attribute for output
|
||||
movb $0xe,%ah # BIOS: put_char
|
||||
int $0x10 # call BIOS, print char in %al
|
||||
@ -217,7 +213,7 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
#
|
||||
# BTX client to start btxldr
|
||||
|
||||
@ -9,8 +9,6 @@ CLEANFILES+= boot1 boot1.out boot1.o \
|
||||
boot2.ldr boot2.bin boot2.ld boot2.out boot2.o \
|
||||
sio.o
|
||||
|
||||
M4?= m4
|
||||
|
||||
# A value of 0x80 enables LBA support.
|
||||
B1FLAGS= 0
|
||||
|
||||
@ -45,9 +43,8 @@ boot1: boot1.out
|
||||
boot1.out: boot1.o
|
||||
${LD} ${LDFLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} boot1.o
|
||||
|
||||
boot1.o: boot1.m4 boot1.s
|
||||
(cd ${.CURDIR}; ${M4} -DFLAGS=${B1FLAGS} boot1.m4 boot1.s) | \
|
||||
${AS} ${AFLAGS} -o ${.TARGET}
|
||||
boot1.o: boot1.s
|
||||
${AS} ${AFLAGS} --defsym FLAGS=${B1FLAGS} ${.IMPSRC} -o ${.TARGET}
|
||||
|
||||
boot2: boot2.ldr boot2.bin ${BTX}/btx/btx
|
||||
btxld -v -E ${ORG2} -f bin -b ${BTX}/btx/btx -l boot2.ldr \
|
||||
@ -67,10 +64,10 @@ boot2.out: boot2.o sio.o
|
||||
${BTX}/lib/crt0.o boot2.o sio.o
|
||||
|
||||
sio.o: sio.s
|
||||
(cd ${.CURDIR}; ${M4} -DSIOPRT=${BOOT_COMCONSOLE_PORT} \
|
||||
-DSIOFMT=${B2SIOFMT} \
|
||||
-DSIOSPD=${BOOT_COMCONSOLE_SPEED} sio.s) | \
|
||||
${AS} ${AFLAGS} -o ${.TARGET}
|
||||
${AS} ${AFLAGS} --defsym SIOPRT=${BOOT_COMCONSOLE_PORT} \
|
||||
--defsym SIOFMT=${B2SIOFMT} \
|
||||
--defsym SIOSPD=${BOOT_COMCONSOLE_SPEED} \
|
||||
${.IMPSRC} -o ${.TARGET}
|
||||
|
||||
install:
|
||||
${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m ${BINMODE} \
|
||||
|
||||
@ -85,31 +85,31 @@ start: cld # string ops inc
|
||||
addl %ebx, %ecx # the PXENV+ struct and
|
||||
pushl %ecx # save it on the stack
|
||||
movw $welcome_msg, %si # %ds:(%si) -> welcome message
|
||||
call putstr # display the welcome message
|
||||
callw putstr # display the welcome message
|
||||
#
|
||||
# Setup the arguments that the loader is expecting from boot[12]
|
||||
#
|
||||
movw $bootinfo_msg, %si # %ds:(%si) -> boot args message
|
||||
call putstr # display the message
|
||||
movl $MEM_ARG, %ebx # %ds:(%ebx) -> boot args
|
||||
callw putstr # display the message
|
||||
movl $MEM_ARG, %bx # %ds:(%bx) -> boot args
|
||||
movw %bx, %di # %es:(%di) -> boot args
|
||||
xorl %eax, %eax # zero %eax
|
||||
movw $(MEM_ARG_SIZE/4), %cx # Size of arguments in 32-bit
|
||||
# dwords
|
||||
rep # Clear the arguments
|
||||
stosl # to zero
|
||||
orb $KARGS_FLAGS_PXE, 0x8(%ebx) # kargs->bootflags |=
|
||||
orb $KARGS_FLAGS_PXE, 0x8(%bx) # kargs->bootflags |=
|
||||
# KARGS_FLAGS_PXE
|
||||
popl 0xc(%ebx) # kargs->pxeinfo = *PXENV+
|
||||
popl 0xc(%bx) # kargs->pxeinfo = *PXENV+
|
||||
#
|
||||
# Turn on the A20 address line
|
||||
#
|
||||
call seta20 # Turn A20 on
|
||||
callw seta20 # Turn A20 on
|
||||
#
|
||||
# Relocate the loader and BTX using a very lazy protected mode
|
||||
#
|
||||
movw $relocate_msg, %si # Display the
|
||||
call putstr # relocation message
|
||||
callw putstr # relocation message
|
||||
movl end+AOUT_ENTRY, %edi # %edi is the destination
|
||||
movl $(end+AOUT_HEADER), %esi # %esi is
|
||||
# the start of the text
|
||||
@ -121,9 +121,8 @@ start: cld # string ops inc
|
||||
movl %cr0, %eax # Turn on
|
||||
orb $0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # long jump to
|
||||
.word pm_start # clear the instruction
|
||||
.word SEL_SCODE # pre-fetch queue
|
||||
ljmp $SEL_SCODE,$pm_start # long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
.code32
|
||||
pm_start: movw $SEL_SDATA, %ax # Initialize
|
||||
movw %ax, %ds # %ds and
|
||||
@ -155,9 +154,8 @@ pm_16: movw $SEL_RDATA, %ax # Initialize
|
||||
movl %cr0, %eax # Turn off
|
||||
andb $~0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # Long jump to
|
||||
.word pm_end # clear the instruction
|
||||
.word 0x0 # pre-fetch
|
||||
ljmp $0,$pm_end # Long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
pm_end: sti # Turn interrupts back on now
|
||||
#
|
||||
# Copy the BTX client to MEM_BTX_CLIENT
|
||||
@ -188,10 +186,8 @@ pm_end: sti # Turn interrupts back on now
|
||||
# Now we just start up BTX and let it do the rest
|
||||
#
|
||||
movw $jump_message, %si # Display the
|
||||
call putstr # jump message
|
||||
.byte 0xea # Jump to
|
||||
.word MEM_BTX_ENTRY # BTX entry
|
||||
.word 0x0 # point
|
||||
callw putstr # jump message
|
||||
ljmp $0,$MEM_BTX_ENTRY # Jump to the BTX entry point
|
||||
|
||||
#
|
||||
# Display a null-terminated string
|
||||
@ -199,7 +195,7 @@ pm_end: sti # Turn interrupts back on now
|
||||
putstr: lodsb # load %al from %ds:(%si)
|
||||
testb %al,%al # stop at null
|
||||
jnz putc # if the char != null, output it
|
||||
ret # return when null is hit
|
||||
retw # return when null is hit
|
||||
putc: movw $0x7,%bx # attribute for output
|
||||
movb $0xe,%ah # BIOS: put_char
|
||||
int $0x10 # call BIOS, print char in %al
|
||||
@ -220,7 +216,7 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
#
|
||||
# BTX client to start btxldr
|
||||
|
||||
@ -85,31 +85,31 @@ start: cld # string ops inc
|
||||
addl %ebx, %ecx # the PXENV+ struct and
|
||||
pushl %ecx # save it on the stack
|
||||
movw $welcome_msg, %si # %ds:(%si) -> welcome message
|
||||
call putstr # display the welcome message
|
||||
callw putstr # display the welcome message
|
||||
#
|
||||
# Setup the arguments that the loader is expecting from boot[12]
|
||||
#
|
||||
movw $bootinfo_msg, %si # %ds:(%si) -> boot args message
|
||||
call putstr # display the message
|
||||
movl $MEM_ARG, %ebx # %ds:(%ebx) -> boot args
|
||||
callw putstr # display the message
|
||||
movl $MEM_ARG, %bx # %ds:(%bx) -> boot args
|
||||
movw %bx, %di # %es:(%di) -> boot args
|
||||
xorl %eax, %eax # zero %eax
|
||||
movw $(MEM_ARG_SIZE/4), %cx # Size of arguments in 32-bit
|
||||
# dwords
|
||||
rep # Clear the arguments
|
||||
stosl # to zero
|
||||
orb $KARGS_FLAGS_PXE, 0x8(%ebx) # kargs->bootflags |=
|
||||
orb $KARGS_FLAGS_PXE, 0x8(%bx) # kargs->bootflags |=
|
||||
# KARGS_FLAGS_PXE
|
||||
popl 0xc(%ebx) # kargs->pxeinfo = *PXENV+
|
||||
popl 0xc(%bx) # kargs->pxeinfo = *PXENV+
|
||||
#
|
||||
# Turn on the A20 address line
|
||||
#
|
||||
call seta20 # Turn A20 on
|
||||
callw seta20 # Turn A20 on
|
||||
#
|
||||
# Relocate the loader and BTX using a very lazy protected mode
|
||||
#
|
||||
movw $relocate_msg, %si # Display the
|
||||
call putstr # relocation message
|
||||
callw putstr # relocation message
|
||||
movl end+AOUT_ENTRY, %edi # %edi is the destination
|
||||
movl $(end+AOUT_HEADER), %esi # %esi is
|
||||
# the start of the text
|
||||
@ -121,9 +121,8 @@ start: cld # string ops inc
|
||||
movl %cr0, %eax # Turn on
|
||||
orb $0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # long jump to
|
||||
.word pm_start # clear the instruction
|
||||
.word SEL_SCODE # pre-fetch queue
|
||||
ljmp $SEL_SCODE,$pm_start # long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
.code32
|
||||
pm_start: movw $SEL_SDATA, %ax # Initialize
|
||||
movw %ax, %ds # %ds and
|
||||
@ -155,9 +154,8 @@ pm_16: movw $SEL_RDATA, %ax # Initialize
|
||||
movl %cr0, %eax # Turn off
|
||||
andb $~0x1, %al # protected
|
||||
movl %eax, %cr0 # mode
|
||||
.byte 0xea # Long jump to
|
||||
.word pm_end # clear the instruction
|
||||
.word 0x0 # pre-fetch
|
||||
ljmp $0,$pm_end # Long jump to clear the
|
||||
# instruction pre-fetch queue
|
||||
pm_end: sti # Turn interrupts back on now
|
||||
#
|
||||
# Copy the BTX client to MEM_BTX_CLIENT
|
||||
@ -188,10 +186,8 @@ pm_end: sti # Turn interrupts back on now
|
||||
# Now we just start up BTX and let it do the rest
|
||||
#
|
||||
movw $jump_message, %si # Display the
|
||||
call putstr # jump message
|
||||
.byte 0xea # Jump to
|
||||
.word MEM_BTX_ENTRY # BTX entry
|
||||
.word 0x0 # point
|
||||
callw putstr # jump message
|
||||
ljmp $0,$MEM_BTX_ENTRY # Jump to the BTX entry point
|
||||
|
||||
#
|
||||
# Display a null-terminated string
|
||||
@ -199,7 +195,7 @@ pm_end: sti # Turn interrupts back on now
|
||||
putstr: lodsb # load %al from %ds:(%si)
|
||||
testb %al,%al # stop at null
|
||||
jnz putc # if the char != null, output it
|
||||
ret # return when null is hit
|
||||
retw # return when null is hit
|
||||
putc: movw $0x7,%bx # attribute for output
|
||||
movb $0xe,%ah # BIOS: put_char
|
||||
int $0x10 # call BIOS, print char in %al
|
||||
@ -220,7 +216,7 @@ seta20.2: inb $0x64,%al # Get status
|
||||
movb $0xdf,%al # Enable
|
||||
outb %al,$0x60 # A20
|
||||
sti # Enable interrupts
|
||||
ret # To caller
|
||||
retw # To caller
|
||||
|
||||
#
|
||||
# BTX client to start btxldr
|
||||
|
||||
Loading…
Reference in New Issue
Block a user