wok-6.x annotate linld/stuff/src/_BEG.ASM @ rev 19571

linld: large image support with VCPI
author Pascal Bellard <pascal.bellard@slitaz.org>
date Thu Dec 22 21:06:17 2016 +0100 (2016-12-22)
parents 31c5cbbd9380
children 38eb1fe036b4
rev   line source
pascal@19515 1 ;***************************************************************
pascal@19515 2 ;****** This file is distributed under GPL
pascal@19515 3 ;***************************************************************
pascal@19515 4 ideal
pascal@19515 5 %crefref
pascal@19515 6 %noincl
pascal@19515 7 %nomacs
pascal@19515 8 p386
pascal@19515 9
pascal@19515 10 group DGROUP _TEXT,_DATA,_BSS
pascal@19515 11 assume cs:DGROUP,ds:DGROUP
pascal@19515 12
pascal@19515 13 segment _TEXT byte public use16 'CODE'
pascal@19515 14
pascal@19515 15 org 100h
pascal@19515 16 global _text_start:byte
pascal@19515 17 label _text_start byte
pascal@19546 18
pascal@19515 19 ;***************************************************************
pascal@19515 20 ; clear bss
pascal@19515 21 ;***************************************************************
pascal@19546 22 mov bx,offset _bss_start
pascal@19515 23 clearbss:
pascal@19546 24 mov [byte bx],0 ; clear bss + heap + sp
pascal@19546 25 inc bx
pascal@19546 26 jne clearbss
pascal@19571 27 cld
pascal@19546 28
pascal@19546 29 ;***************************************************************
pascal@19546 30 ; check CPU
pascal@19546 31 ;***************************************************************
pascal@19546 32
pascal@19546 33 ; Check for oldies
pascal@19546 34 mov bh, 0F0h
pascal@19546 35 pushf
pascal@19546 36 push bx ; < 286 : flags[12..15] are forced 1
pascal@19546 37 popf ; = 286 : flags[12..15] are forced 0
pascal@19546 38 pushf ; > 286 : only flags[15] is forced 0
pascal@19546 39 pop dx
pascal@19546 40 popf
pascal@19546 41 add dh,bh ; NS=386+, NC=286
pascal@19571 42 mov bx,offset msg_badcpu
pascal@19546 43 ifndef NO386
pascal@19546 44 js no_vcpi ;it is a 86/186/286, not a 386+
pascal@19546 45 else
pascal@19546 46 js endcpu
pascal@19546 47 endif
pascal@19546 48 ; Check for vm
pascal@19546 49 smsw ax ;SMSW cannot be trapped! :-)
pascal@19571 50 and al,1 ;MSW_PE
pascal@19546 51 ; We're in vm
pascal@19571 52 jz check_rm_paging
pascal@19546 53
pascal@19546 54 ;***************************************************************
pascal@19546 55 ; checks for vcpi
pascal@19546 56 ;***************************************************************
pascal@19546 57 label check_vcpi near
pascal@19546 58 push ds
pascal@19546 59 ; Check whether it is safe to call 67h (we trust only known EMM managers)
pascal@19546 60 push 0
pascal@19546 61 pop ds
pascal@19546 62 mov ds,[word 67h*4+2]
pascal@19546 63 cmp [dword 10+4],'0XXX'
pascal@19546 64 jne skip
pascal@19546 65 mov eax,'XMME'
pascal@19546 66 xor eax,[dword 10]
pascal@19546 67 ; QMME also works (as told by <J.S.Peatfield@damtp.cambridge.ac.uk>)
pascal@19546 68 shl eax,8
pascal@19546 69 skip:
pascal@19546 70 pop ds
pascal@19546 71 jne no_vcpi
pascal@19546 72
pascal@19546 73 ; Check emm manager status and version
pascal@19571 74 ;mov ah,40h ; get status
pascal@19571 75 ;int 67h
pascal@19571 76 ;test ah,ah
pascal@19571 77 ;jnz no_vcpi
pascal@19546 78 mov ah,46h ; get version
pascal@19546 79 int 67h
pascal@19546 80 test ah,ah
pascal@19546 81 jnz no_vcpi
pascal@19546 82 cmp al,40h ; version must be >= 4.0
pascal@19546 83 jb no_vcpi
pascal@19546 84 ; Check vcpi manager status
pascal@19546 85 ;;mov ax,5A01h ; ALLOCATE RAW PAGES
pascal@19546 86 ;;mov bx,4
pascal@19546 87 ;;int 67h
pascal@19546 88 ;;test ah,ah
pascal@19546 89 ;;jnz no_vcpi
pascal@19546 90 ;;push dx ;$ save handle
pascal@19546 91 mov ax,0DE00h ; check for vcpi present
pascal@19546 92 int 67h
pascal@19546 93 test ah,ah
pascal@19571 94 jnz no_vcpi
pascal@19546 95 is386vcpi:
pascal@19571 96 inc [_vcpi]
pascal@19546 97 extrn prepare_vcpi:near
pascal@19546 98 call prepare_vcpi
pascal@19546 99 ; get_vcpi_interface() || die("VCPI: low 640k: need 1:1 mapping");
pascal@19546 100 ;extrn _get_vcpi_interface:near
pascal@19546 101 ;call _get_vcpi_interface
pascal@19546 102 mov bx,offset msg_badmapping
pascal@19571 103 jnz endcpu
pascal@19571 104 no_vcpi:
pascal@19571 105 ;;pop dx ;$ handle
pascal@19571 106 ;;mov ax,4500h ; DEALLOCATE PAGES
pascal@19571 107 ;;int 67h
pascal@19571 108 extrn die:near
pascal@19571 109 godie:
pascal@19571 110 jmp near die
pascal@19571 111 check_rm_paging:
pascal@19571 112 ; It's a 386 in real mode, chk for paging (crazy but possible)
pascal@19571 113 mov edx,cr0
pascal@19571 114 shl edx,1 ;CR0_PG to CF
pascal@19571 115 jc no_vcpi
pascal@19546 116 endcpu:
pascal@19546 117
pascal@19515 118 ;***************************************************************
pascal@19515 119 ; build argv & argc
pascal@19515 120 ;***************************************************************
pascal@19546 121 extrn _heap_top:word
pascal@19546 122 mov di,[_heap_top]
pascal@19546 123 ;xor ax,ax
pascal@19546 124 ;push ax ; envp (already cleared)
pascal@19546 125 ;mov [word di],ax ; argv[0] = 0 (idem)
pascal@19515 126 mov si,80h
pascal@19515 127 lodsb
pascal@19515 128 cmp al,7Eh
pascal@19515 129 jbe alok
pascal@19515 130 mov al,7Eh
pascal@19515 131 alok:
pascal@19546 132 cbw
pascal@19515 133 xchg ax,bx
pascal@19515 134 mov [bx+si],bh ; set eos
pascal@19515 135 argbuild:
pascal@19515 136 mov bx,2 ; argc * 2
pascal@19515 137 argeos:
pascal@19515 138 mov dl,1 ; look for a start of string
pascal@19515 139 mov [byte si-1],bh ; mark eos
pascal@19515 140 mov ah,20h ; space will be eos
pascal@19515 141 arglp:
pascal@19515 142 lodsb
pascal@19515 143 cmp al,0h
pascal@19515 144 je argdone
pascal@19515 145 cmp al,20h
pascal@19515 146 jb argeos
pascal@19515 147 cmp al,ah
pascal@19515 148 je argeos
pascal@19515 149 cmp al,27h
pascal@19515 150 je isargstr
pascal@19515 151 cmp al,22h
pascal@19515 152 je isargstr
pascal@19515 153 or dl,dl
pascal@19515 154 je arglp ; not start of string
pascal@19515 155 dec si
pascal@19515 156 jmp newarg
pascal@19515 157 isargstr:
pascal@19515 158 mov ah,al ; expected eos
pascal@19515 159 newarg:
pascal@19515 160 mov [word bx+di],si ; argv[argc++] = si
pascal@19515 161 inc bx
pascal@19515 162 inc bx
pascal@19515 163 dec dx
pascal@19515 164 jmp arglp
pascal@19515 165 argdone:
pascal@19515 166 ;mov [word bx+di],0 ; argv[argc] = 0
pascal@19546 167 lea ax,[bx+di+2]
pascal@19546 168 mov [_heap_top],ax
pascal@19515 169 push di ; argv
pascal@19515 170 shr bx,1
pascal@19515 171 push bx ; argc
pascal@19515 172 ifndef filearg
pascal@19515 173 mov bx,[di+2] ; argv[1]
pascal@19515 174 cmp [byte bx],'@'
pascal@19515 175 jne argend
pascal@19546 176 inc bx
pascal@19515 177 extrn open:near
pascal@19515 178 call near open
pascal@19515 179 jc argend
pascal@19515 180 pop bx ; trash argc, argv >> 1Kb !
pascal@19546 181 global read_cmdline:near
pascal@19546 182 read_cmdline:
pascal@19515 183 push di
pascal@19515 184 push ax
pascal@19515 185 extrn _read:near
pascal@19515 186 call near _read
pascal@19515 187 pop bx ; fd for close
pascal@19515 188 pop si ; si=buffer=argv
pascal@19515 189 add di,ax
pascal@19515 190 pop ax ; trash sizemax=argv
pascal@19515 191 extrn close:near
pascal@19515 192 call near close
pascal@19515 193 jmp argbuild
pascal@19515 194 argend:
pascal@19515 195 endif
pascal@19515 196
pascal@19515 197 ;***************************************************************
pascal@19515 198 extrn _main:near
pascal@19515 199 call _main
pascal@19538 200
pascal@19515 201 ;***************************************************************
pascal@19515 202 global exit:near
pascal@19515 203 exit:
pascal@19515 204 mov ah,4Ch
pascal@19515 205 int 21h
pascal@19515 206 ends _TEXT
pascal@19515 207
pascal@19515 208 segment _DATA byte public use16 'DATA'
pascal@19515 209 global _data_start:byte
pascal@19515 210 label _data_start byte
pascal@19546 211 msg_badcpu db "I need 386+ CPU in real mode or under VCPI manager"
pascal@19546 212 global _vcpi:byte
pascal@19546 213 _vcpi db 0
pascal@19546 214 msg_badmapping db "VCPI: low 640k: need 1:1 mapping",0
pascal@19546 215
pascal@19515 216 ends _DATA
pascal@19515 217
pascal@19515 218 segment _BSS byte public use16 'BSS'
pascal@19515 219 global _bss_start:byte
pascal@19515 220 label _bss_start byte
pascal@19515 221 ends _BSS
pascal@19515 222
pascal@19515 223 end _text_start
pascal@19515 224
pascal@19515 225 ;###### END OF FILE ############################################