diff options
Diffstat (limited to 'private/mvdm/dpmi/dxvcpi.asm')
| -rw-r--r-- | private/mvdm/dpmi/dxvcpi.asm | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/private/mvdm/dpmi/dxvcpi.asm b/private/mvdm/dpmi/dxvcpi.asm new file mode 100644 index 000000000..b9d9a0308 --- /dev/null +++ b/private/mvdm/dpmi/dxvcpi.asm @@ -0,0 +1,586 @@ + PAGE ,132 + TITLE DXVCPI.ASM -- Dos Extender VCPI Support Code + +; Copyright (c) Microsoft Corporation 1990-1991. All Rights Reserved. + +;*** dxvcpi.asm - vcpi detection/maintenance/cleanup code (resident) +; +; Copyright <C> 1990, Microsoft Corporation +; +; Purpose: +; +; Revision History: +; +; +; 08-07-90 earleh Allow program to boot without LIM 3.2 page frame. +; 05/07/90 jimmat Started incorporating VCPI changes from languages group. +; +; [] 20-Feb-1990 Dans Created +; +;************************************************************************/ + +.286p + +; ------------------------------------------------------- +; INCLUDE FILE DEFINITIONS +; ------------------------------------------------------- + +.xlist +.sall +include segdefs.inc +include gendefs.inc +include pmdefs.inc +.list + +; This entire file is only for VCPI support + +if VCPI + +.xlist +.sall +include dxvcpi.inc +.list +; +; miscellaneous equates +; +; +; also in dxmmgr.asm +; +.ERRE CB_MEMHDR EQ 10h ;size of memory block header +; +; also in dxmmgr.asm +; +; +; data +; + +DXDATA segment + +; +; Externs +; + +extrn idCpuType:word +extrn bpGDT:fword + +extrn cKbInitialHeapSize:word +extrn cbHeapSize:dword +extrn dsegCurrent:word +extrn hmemHeap:word +extrn lpfnXMSFunc:DWORD + +extrn selGDT:WORD +; +; Definitions, data +; + +public fEms +fEMS db 0 ; ems present + +public fVCPI +fVCPI db 0 ; vcpi present + +public iddxsystype +iddxsystype db DXINDOS ; type of memory used to hold + ; final dx Pmode data. +public segBootPmode +segBootPmode dw 0 ; segment of block used to + ; build system tables in real +align 4 + +public cFreePages +cFreePages dd 0 ; free 4k pages, updated on each + ; allocation. +public bpdxsyspages +bpdxsyspages dd DXPMPAGES-1 dup(0) +; +; pointer (off of SEL_DXPT) where next free page table entry is +; +; we initialize dxpt1 to have cptdx+2 entries in it (see +; SetupPageTables in dxvcpibt.asm) +; + +; +; Offset in zeroth page table of first page table entry that belongs +; to DX. Set by initial call to GetVCPIInterface. +; +public pPteFirst +pPteFirst dd 0 + +; +; Offset in block pointed to by SEL_DXPT of where to put next page +; table entry when allocating extended memory by the page. +; +public pPteNext +pPteNext dd 0 + +; +; Maximum number of user page table entries that will fit in our +; original page table buffers. +; +public cPteMax +cPteMax dd 0 + +EXTRN hmem_XMS_Table:WORD +EXTRN hmem_XMS_Count:WORD + +public hmem_System_Block +hmem_System_Block dw 0 + +DXDATA ends + + +DXPMCODE segment + +IFDEF ROM + %OUT VCPI Support not compatible with ROM! Code segment variables! + .ERR +ENDIF + +; +; Data set up in real mode prior to relocation of DX into vcpi +; (read only after init time anyway) +; + +public fnVCPIPM, fnVCPIPMoff + +fnVCPIPM label fword ; vcpi interface entrypoint +fnVCPIPMoff dd 0 ; set up in GetVCPIInterface + dw SEL_VCPI ; we know what this is. + +externFP NSetSegmentDscr + extrn XMScontrol:FAR + +pmxmssvc macro fcn + ifnb <fcn> + mov ah, fcn + endif + call XMScontrol +endm + +DXPMCODE ends + +DXCODE segment +; +; Data set up in real mode prior to relocation of DX into vcpi +; (read only after init time anyway) +; + +public WdebVCPI, fnVCPI, fnVCPIoff + +;--------- WdebVCPIInfo structure ----------- + +public laVTP, V86ToPm + +; +; Begin WDEB386 VCPI notification structure. The following variables +; are copied by WDEB386 when we send it a VCPI presence notification, +; just after entering protected mode. The structure of this block of variables +; must not be changed without also changing the format of the data +; structure used by WDEB386. +; +;--------- WdebVCPIInfo structure ----------- +WdebVCPI LABEL BYTE + +fnVCPI label fword ; vcpi interface entrypoint +fnVCPIoff dd 0 ; set up in GetVCPIInterface + dw SEL_VCPI ; we know what this is. + + dw SEL_VCPIALLMEM ; for Wdeb386 information + +laVTP dd 0 ; linear address of next structure +; +; End WDEB386 VCPI notification structure. +; + +; Structure for switching from v86 mode to protect mode via VCPI + + EXTRN epmVCPI:BYTE + +V86ToPm VTP <,,, SEL_LDT, SEL_TSS, OFFSET epmVCPI, 0, SEL_DXCODE0> + + externFP AddXMStoVCPIHeap + +DXCODE ends + + +DXCODE segment + + assume cs:DXCODE, ds:DXDATA, es:nothing + + +;*** FreeEMSHandle - free DX system memory +; +; Purpose: free the VCPI pages OR XMS block we allocated for system use +; +; Register +; Usage: eax, edx, si, cx +; +; Input: none +; +; Output: VCPI DOS Extender system pages freed +; XMS handle deallocated +; +; Returns: nothing +; +; Exceptions: No operation if none of these entities have been +; allocated yet +; +; Notes: +; +;************************************************************************/ +cProc FreeEMSHandle,<NEAR,PUBLIC,<> +cBegin + lea si,bpdxsyspages ; Load VCPI system pages array. + mov cx,DXPMPAGES-1 ; (First page was in PSP block.) + cld +.386 +FreeVCPI_syspage: + lodsd ; fetch next page + or eax,eax ; page present? + jz FreeVCPI_Done ; No, could have been XMS. + and ax,0f000h ; Yes, clear lower 12 bits. + mov edx,eax + RMvcpi vcpiFREEPAGE ; and free it. + loop FreeVCPI_syspage ; loop until all freed +.286p +FreeVCPI_Done: + test iddxsystype,DXINXMS ; loaded in XMS? + jz FreeEMSHandle_ret ; No. + mov dx,hmem_System_Block ; Yes, load block + xmssvc 0dh ; unlock XMS block + mov dx,hmem_System_Block + xmssvc 0ah ; free XMS block +FreeEMSHandle_ret: +cEnd + +DXCODE ends + +;************************************************************** +; 386 only code from here on down!!! +;************************************************************** +.386p + +include prot386.inc + +DXCODE segment + + assume cs:DXCODE, ds:DXDATA, es:nothing + +DXCODE ends + + +DXPMCODE segment + assume cs:DXPMCODE + +;************************************************************** +;*** CallVCPIPM +; +; Utility routine to call VCPI server in protected mode. Masks out +; interrupts during the call because QEMM enables the processor +; interrupt flag when you call it. +; +; Entry: AX = VCPI function code. +; Uses: Depends upon call. +; +; Note: There is a copy of this routine in dxvcpi.asm and another +; in dxvcpibt.asm. This is to allow near calls. The copy +; in dxvcpibt.asm is discarded after initialization time. +; +;************************************************************** +cProc CallVCPIPM,<NEAR>,<si> +cBegin + + push ax ; save function code +; +; Shut out all interrupts. +; QEMM 5.0 enables interrupts during this call. All our interrupt +; handlers are in the user code ring. A workaround is to shut off +; hardware interrupts during the call. +; + + in al,INTA01 + IO_Delay + mov si, ax + mov al,0FFh + out INTA01,al + IO_Delay + + pop ax ;restore function code + db 9Ah ;call far SEL_CALLVCPI:0 + dw 0,SEL_CALLVCPI or STD_RING + +; Restore the state of the interrupt mask register + + xchg si, ax + out INTA01,al + IO_Delay + xchg si, ax +cEnd + +;************************************************************************/ +;*** AllocVCPIMem +; +; Purpose: to allocate a block of memory from VCPI +; +; Register +; Usage: eax, ebx, edx, ecx, es +; +; Input: ECX has number of 4k pages to allocate +; ES:EDI points to page table entries to fill. +; +; Output: pPteNext updated with next free pte +; cFreePages updated with number of free 4k pages from vcpi +; +; Returns: if success, linear ptr in eax +; if fail, eax 0, ebx has number of 4k pages available. +; +; Exceptions: +; +; Notes: maximum allocation is 65535 4k pages (more than enough) +; at one time. +; Also, this is PROTECT MODE ONLY. +; +;************************************************************************/ +cProc AllocVCPIMem,<NEAR,PUBLIC>,<bx,dx> +cBegin + ; + ; Compute the number of entries free in our page table + ; + mov edx, cPteMax + cmp ecx, edx ; compare request with PTEs + jb @F + ; + ; our page tables have less room than the vcpi server can allocate, + ; so adjust our count downward to reflect that + ; + mov ecx, edx +@@: + cmp ecx, cFreePages ; compare request with pages we are + ; allowed to allocate + jb @F ; request < max.? + mov ecx, cFreePages ; No, clip. +@@: + jecxz AVM_exit ; ECX = pages to allocate + +AVM_getpage: + + PMvcpi vcpiALLOCPAGE + + or ah, ah + jnz AVM_exit ; something happened...not as much + ; as vcpi said was there. + dec cPteMax ; fix up free PTEs + dec cFreePages ; and free VCPI pages +; +; make it a page table entry, and store into page table +; don't need to worry about the tlb here, since not-present +; pages are not cached in the tlb. +; + or dx, NEWPTEMASK + mov eax, edx + stos dword ptr es:[edi] + + dec ecx + jnz AVM_getpage ; next allocate + +AVM_exit: +cEnd + +;************************************************************************/ +;*** VCPISpace +; +; Purpose: Return maximum possible VCPI memory allocation. +; +; Uses: +; +; Input: +; +; Output: +; +; Return: EAX = maximum possible VCPI pages we can get. +; +; Exceptions: +; +; Notes: +; +;************************************************************************/ +cProc VCPISpace,<NEAR,PUBLIC>,<edx> +cBegin + + PMvcpi vcpiCFREEPAGES ; EDX = free VCPI pages + cmp edx,cFreePages ; clip to maximum EMS allocation + jb VS_00 + mov edx,cFreePages +VS_00: + mov eax,cPteMax ; clip to space in page tables + cmp edx,eax + jb VS_01 + mov edx,eax +VS_01: + mov eax,edx +cEnd + +;************************************************************************/ +;*** FreeVCPIHeap +; +; Purpose: To free the Extended Memory heap memory. +; +; Register +; Usage: eax, ebx, ecx, edx +; +; Input: +; +; Output: All VCPI pages allocated for the heap are freed. +; All XMS blocks allocated for the heap are freed. +; Page table entries are set to zero. +; +; +; Returns: nothing +; +; Exceptions: none +; +; Notes: Protect mode only +; +;************************************************************************/ +cProc FreeVCPIHeap,<NEAR,PUBLIC>,<es,edi,si,eax,edx> +cBegin + + mov ax, SEL_DXPT ; set up es with the selector + mov es, ax ; for our page tables + mov edi, pPteFirst ; point to first page allocated + mov ecx, pPteNext ; point to first unallocated PTE + sub ecx, edi + jbe Free_XMS_Handles + shr ecx, 2 ; ECX = pages to free + +startloop: + mov edx, es:[edi] ; get pte into edx + and dx, 0f000h ; mask off 12 lsb's + + PMvcpi vcpiFREEPAGE ; free the page + + xor eax, eax + stos dword ptr es:[edi] ; clear out PTE + dec ecx + jnz startloop +@@: +Free_XMS_Handles: + lea si, hmem_XMS_Table ; si points to XMS handle array + mov cx,[hmem_XMS_Count] + jcxz No_XMS_Handles + +Free_XMS_Handles_Loop: + mov dx,[si] + pmxmssvc 0dh ; unlock any XMS blocks + mov dx,[si] + pmxmssvc 0ah ; free any XMS blocks + add si,2 ; point to next slot in handle array + loop Free_XMS_Handles_Loop ; loop if more handle slots + +No_XMS_Handles: + +cEnd + +AddXMStoVCPIHeapCall label dword + dw offset dxcode:AddXMStoVCPIHeap,SEL_DXCODE or STD_RING + +;*** AddVCPIHeap +; +; Purpose: to replace the himem specific code in AddToXmemHeap +; +; Register +; Usage: all preserved except return values in bx:dx +; +; Input: dx:cx is the minimum block length required (bytes). +; +; Output: cbHeapSize is updated if a heap is allocated +; +; Returns: bx:dx is 32bit linear address of allocated block if success, +; cy clear, else cy set +; +; Exceptions: +; +; Notes: +; +;************************************************************************/ +cProc AddVCPIHeap,<NEAR,PUBLIC>,<eax,ecx> +localD cbNeeded +cBegin + + push ebx ; save extended registers + push edx + + add cx, CB_MEMHDR * 3 ; add memory manager overhead + adc dx, 0 + movzx ecx,cx + shl edx,16d + or ecx,edx ; ECX = minimum bytes wanted + mov cbNeeded,ecx + add ecx,CBPAGE386-1 + shr ecx,12d ; ECX = minimum pages wanted + mov eax, cPteMax + cmp ecx,eax ; make sure we have enough + jna AVH_00 ; page table entries + mov ecx,eax ; ECX = minimum pages wanted +AVH_00: + + mov cbHeapSize,0 + + mov ax, SEL_DXPT ; ES -> user page tables + mov es, ax + mov edi, pPteNext ; Point to first unused PTE + or edi, edi ; Initialized? + jnz AVH_10 ; Yes, skip XMS allocate. + mov edi, pPteFirst ; No, initialize first unused PTE. + mov pPteNext, edi + + cCall AddXMStoVCPIHeapCall + + mov pPteFirst,edi ; VCPI allocations start here + +AVH_10: + mov ebx, pPteNext ; EBX = first PTE + shl ebx, 10d ; EBX = linear address of start of block + mov dx, bx + shr ebx, 16d ; DX:BX = linear address of block + + mov eax, edi + sub eax, pPteNext + shr eax, 2 ; AX = count of pages allocated + sub ecx, eax ; Get what we asked for? + jbe AVH_Done ; Yes. + + cCall AllocVCPIMem ; allocate it from VCPI + ; cx has number of 4k pages +AVH_Done: + mov eax, edi + sub eax, pPteNext + mov pPteNext, edi + or eax, eax + jz AVH_BadExit + shl eax, 10d ; EAX = count of bytes allocated + sub eax, CB_MEMHDR * 3 ; deduct overhead + mov cbHeapSize, eax + clc + jmp AVH_Exit +AVH_BadExit: + stc +AVH_Exit: +; +; Result is in BX:DX, but we have to save restore the MSW of EBX and +; that of EDX before we return to our caller. +; + mov ax,dx + pop edx + mov dx,ax + mov ax,bx + pop ebx + mov bx,ax +cEnd + +DXPMCODE ends + +endif ;VCPI + + end |