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DPMI works now with allocated descriptiors.
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DPMI 32 has the problem that its stack is too large for
64 K. BIOS31 doesn't work.
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albert committed Oct 31, 2001
1 parent 5cb9fd6 commit 95d6456
Showing 1 changed file with 41 additions and 27 deletions.
68 changes: 41 additions & 27 deletions ci86.gnr
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Original file line number Diff line number Diff line change
Expand Up @@ -245,8 +245,9 @@ MAXCHUNK EQU 1024 *100000H /CHUNKSIZE
_HOSTED_DPMI_({
;{DPMI segment defines.}
;{We can't aim for better than level privilege level 3.}
IDENTIFY_TOGGLE EQU 040H ;{ The Big and Granularity bits are complemented}
IDENTIFY_TOGGLE EQU 040H ;{ The Big (and Granularity, not yet) bits are complemented}
;{ on switching to 32 bits mode in 6th byte.}
CODE_TOGGLE EQU 08H ;{ Toggle between code and data, in the 5th byte.}
});_END_({_HOSTED_DPMI_})
_SWITCH_({
;{ Segments @ Valid in real mode % Valid in protected mode }
Expand Down Expand Up @@ -832,8 +833,6 @@ EMsgS EQU $-EMsg

; If we reach this point, we are operating in protected mode
DPMISUCCESS:
_SUPPRESSED({ DON'T BOTHER WITH THIS FOR THE MOMENT.
IT MAKES NO SENSE FOR 16 BITS, AND DOESN'T WORK FOR 32 BITS
; -------------- Alias descriptors for CS and DS --------
MOV AX,000AH ;{Alias for LDT descriptor.}
MOV BX,CS
Expand All @@ -849,7 +848,7 @@ IT MAKES NO SENSE FOR 16 BITS, AND DOESN'T WORK FOR 32 BITS
MOV DX,AX
ERRMSG2: JC ERRMSG ;{Could not allocate.}

; -------------- Adapt the segments to 32 bits --------
; -------------- Get new segments, possibly 32 bits --------
; Throughout this section : CX is an alias for CS , DX for DS.

LEA DI,[Scratch]
Expand All @@ -860,9 +859,10 @@ ERRMSG2: JC ERRMSG ;{Could not allocate.}
JC ERRMSG2
MOV AL,[DI+6]
_BITS32_({ XOR AL, IDENTIFY_TOGGLE },{dnl})
MOV AL,0FAH
MOV [DI+5],AL
MOV [DI+6],AL
MOV AL,[DI+5]
XOR AL, CODE_TOGGLE
MOV [DI+5],AL
MOV AX,000CH ;{Set Description.}
MOV BX,CX
INT 31H
Expand All @@ -884,16 +884,14 @@ _BITS32_({ XOR AL, IDENTIFY_TOGGLE },{dnl})
JC ERRMSG2

; -------------- Use the alias descriptors for CS and DS --------
THE POINT OF THIS VIRTUOSO DISPLAY, WASTE ANOTHER 64 K OF MEMORY.
MOV ES,CX ;{CX -> ES -> CS}.
ES
JMP SWITCHSEG
SWITCHSEG:
PUSH CX ; {Corrected code segment}
MOV BX, HERE6
PUSH BX ; {Correct program counter}
RETF ; {Returning to HERE6 now}
HERE6:
MOV DS,DX
});_END_({_SUPPRESSED})
MOV AX,DS
MOV ES,AX
MOV SS,AX
MOV ES,DX
MOV SS,DX
; ######################### DPMI END ###############################################################

});_END_({_HOSTED_DPMI_})
Expand Down Expand Up @@ -1686,7 +1684,7 @@ USINI: DC STRUSA ;{ User area currently in use, cold value same as next.}
DC STRTIB ;{ INIT (TIB) 4}
DC BSIN ;{ RUBOUT: get rid of latest char 5}
DC 0 ;{ AVAILABLE 6}
DC 1 ;{ INIT (WARNING) 7}
DC 0 ;{ INIT (WARNING) 7}
DC INITDP ;{ INIT (FENCE) 8}
DC INITDP ;{ INIT (DP) 9}
DC _DEA(ENV) ;{ INIT (VOC-LINK) 10}
Expand Down Expand Up @@ -2574,6 +2572,28 @@ _BITS16_({_SWITCH_({ JMPHERE_FROM_PROT},{dnl})},{dnl})
_BITS16_({_SWITCH_({ JMPHERE_FROM_REAL},{dnl})},{dnl})
_NEXT
;
worddoc( {MEMORY},{LES},{load_extra_segment},{seg --- seg1},{},
{Change the value of the extra segment register forthvar({ES})
temporarily to forthvar({seg}) leaving the old value forthvar({seg1}) .
The target of the
the forthcode({MOVE}) and forthcode({CMOVE}) instructions will now
be in the new extra segment instead of the data segment.
This word must be used in a definition in pairs such that upon exit
forthvar({ES}) has its original value.
Typically used in the form forthsamp({<something> LES BUFFER
FAR-BUFFER <amount> MOVE LES DROP }). _VERBOSE_({Normally
forthvar({ES}) is the same as forthvar({DS}) , leaving it
different may lead to a crash.})
},
{{L@},{L!}},
{{." No test"},{No test} },
enddoc)
CODE_HEADER({LES},{LLES})
POP AX
PUSH ES
MOV ES, AX
_NEXT
;
});_END_({_LOAD_})
worddoc( {DEFINING},{:},{colon},{},{ISO,FIG,E,L0},
{Used in the form called a colon-definition:
Expand Down Expand Up @@ -6149,7 +6169,7 @@ Under DPMI we have to do this via a special call to the
unadorned interrupt, which is in this case protected mode,
interrupt 31H function 0300H. In behalf of this registers are
saved and restored in forthcode({REG-SET}) . Unadorned calls to
real intterupts are only available as forthcode({BIOSP}) .})
real interrupts are only available as forthcode({BIOS31}) .})
_VERBOSE_({ forthsamp({1 AND}) leaves a zero if the call was successful.})
},{{BDOS}}, {}, enddoc)
_NORMAL_BIOS_({
Expand Down Expand Up @@ -6260,8 +6280,8 @@ SaveCS: DW 0000
SaveSP: DW 0000
SaveSS: DW 0000
;
worddoc( {OPERATINGSYSTEM},{BIOSP},{biosp},{a b c d di---ar br cr dr fl},{},
{Do a call of ``BIOS'' interrupt 2FH, directly from
worddoc( {OPERATINGSYSTEM},{BIOS31},{bios31},{a b c d di---ar br cr dr fl},{},
{Do a call of ``BIOS'' interrupt 31H, directly from
protected mode. _VERBOSE_({The word forthcode({BIOS}) simulates
a real mode interrupt; that is what you usually want.})
dnl forthsamp({i})
Expand All @@ -6278,21 +6298,17 @@ forthsamp({1 AND}) leaves a zero if the call was successful.})
; In protected mode with different selectors for code
; and data this is dubious. If it turns out to work, this could
; be made in a general trap generator.
CODE_HEADER({BIOSP},{BIOSP})
CODE_HEADER({BIOS31},{BIOS31})
POP DI
POP DX
POP CX
POP BX
POP AX
PUSH HIP ;{ Save Forth registers. NEEDED? }
PUSH RPO
XCHG SI,AX ;{ Save AX in (already free) SI}
XCHG {SI},{AX}
RQBIOS: INT(2FH) ;{ Request number to be overwritten.}
RQBIOS: INT(31) ;{ Request number to be overwritten.}
PUSHF ;{ Save status into DI }
POP {DI}
XCHG {SI},{AX} ;{ Save AX in (still free) SI }
XCHG SI,AX
POP RPO ;{ Restore Forth registers. NEEDED? }
POP HIP
PUSH AX
Expand All @@ -6301,8 +6317,6 @@ RQBIOS: INT(2FH) ;{ Request number to be overwritten.}
PUSH DX
PUSH DI ;{ i.e. flags }
_NEXT
;{ Not yet self modifying, but we want to. }
;{ SELF MODIFYING CODE ENDS HERE! YOU HAVE BEEN WARNED!}
});_END_({_SIMULATE_BIOS_})
worddoc( {OPERATINGSYSTEM},{BDOS},{bdos},{a b c d i---ar br cr dr fl},{},
{Do a call of ``BDOS'' interrupt (21H) with forthsamp({a b c d}) in
Expand Down

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