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dosbox-wii/src/ints/ems.cpp
Carl.Kenner a0ed243c23 DOSBox 0.61
2009-05-02 21:53:27 +00:00

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/*
* Copyright (C) 2002-2004 The DOSBox Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* $Id: ems.cpp,v 1.31 2004/02/02 20:23:54 qbix79 Exp $ */
#include <string.h>
#include <stdlib.h>
#include "dosbox.h"
#include "callback.h"
#include "mem.h"
#include "paging.h"
#include "bios.h"
#include "keyboard.h"
#include "regs.h"
#include "inout.h"
#include "dos_inc.h"
#include "setup.h"
#define EMM_PAGEFRAME 0xE000
#define EMM_PAGEFRAME4K ((EMM_PAGEFRAME*16)/4096)
#define EMM_MAX_HANDLES 100 /* 255 Max */
#define EMM_PAGE_SIZE (16*1024U)
#define EMM_MAX_PAGES (32 * 1024 / 16 )
#define EMM_MAX_PHYS 4 /* 4 16kb pages in pageframe */
#define EMM_VERSION 0x40
#define NULL_HANDLE 0xffff
#define NULL_PAGE 0xffff
/* EMM errors */
#define EMM_NO_ERROR 0x00
#define EMM_SOFT_MAL 0x80
#define EMM_HARD_MAL 0x81
#define EMM_INVALID_HANDLE 0x83
#define EMM_FUNC_NOSUP 0x84
#define EMM_OUT_OF_HANDLES 0x85
#define EMM_OUT_OF_PHYS 0x87
#define EMM_OUT_OF_LOG 0x88
#define EMM_ZERO_PAGES 0x89
#define EMM_LOG_OUT_RANGE 0x8a
#define EMM_ILL_PHYS 0x8b
#define EMM_PAGE_MAP_SAVED 0x8d
#define EMM_INVALID_SUB 0x8f
#define EMM_FEAT_NOSUP 0x91
#define EMM_MOVE_OVLAP 0x92
#define EMM_MOVE_OVLAPI 0x97
#define EMM_NOT_FOUND 0xa0
class device_EMM : public DOS_Device {
public:
device_EMM(){name="EMMXXXX0";}
bool Read(Bit8u * data,Bit16u * size) { return false;}
bool Write(Bit8u * data,Bit16u * size){
LOG(LOG_IOCTL,LOG_NORMAL)("EMS:Write to device");
return false;
}
bool Seek(Bit32u * pos,Bit32u type){return false;}
bool Close(){return false;}
Bit16u GetInformation(void){return 0x8093;}
private:
Bit8u cache;
};
struct EMM_Mapping {
Bit16u handle;
Bit16u page;
};
struct EMM_Handle {
Bit16u pages;
MemHandle mem;
char name[8];
bool saved_page_map;
EMM_Mapping page_map[EMM_MAX_PHYS];
};
static EMM_Handle emm_handles[EMM_MAX_HANDLES];
static EMM_Mapping emm_mappings[EMM_MAX_PHYS];
static Bitu call_int67,call_vdma;
struct MoveRegion {
Bit32u bytes;
Bit8u src_type;
Bit16u src_handle;
Bit16u src_offset;
Bit16u src_page_seg;
Bit8u dest_type;
Bit16u dest_handle;
Bit16u dest_offset;
Bit16u dest_page_seg;
};
static Bit16u EMM_GetFreePages(void) {
Bitu count=MEM_FreeTotal()/4;
if (count>0x7fff) count=0x7fff;
return (Bit16u)count;
}
static bool INLINE ValidHandle(Bit16u handle) {
if (handle>=EMM_MAX_HANDLES) return false;
if (emm_handles[handle].pages==NULL_HANDLE) return false;
return true;
}
static Bit8u EMM_AllocateMemory(Bit16u pages,Bit16u & handle) {
/* Check for 0 page allocation */
if (!pages) return EMM_ZERO_PAGES;
/* Check for enough free pages */
if ((MEM_FreeTotal()/4)<pages) { handle=NULL_HANDLE; return EMM_OUT_OF_LOG;}
handle=1;
/* Check for a free handle */
while (emm_handles[handle].pages!=NULL_HANDLE) {
if (++handle>=EMM_MAX_HANDLES) {handle=NULL_HANDLE;return EMM_OUT_OF_HANDLES;}
}
MemHandle mem=MEM_AllocatePages(pages*4,false);
if (!mem) E_Exit("EMS:Memory allocation failure");
emm_handles[handle].pages=pages;
emm_handles[handle].mem=mem;
return EMM_NO_ERROR;
}
static Bit8u EMM_ReallocatePages(Bit16u handle,Bit16u & pages) {
/* Check for valid handle */
if (!ValidHandle(handle)) return EMM_INVALID_HANDLE;
/* Check for enough pages */
if (!MEM_ReAllocatePages(emm_handles[handle].mem,pages*4,false)) return EMM_OUT_OF_LOG;
/* Update size */
emm_handles[handle].pages=pages;
return EMM_NO_ERROR;
}
static Bit8u EMM_MapPage(Bitu phys_page,Bit16u handle,Bit16u log_page) {
// LOG_MSG("EMS MapPage handle %d phys %d log %d",handle,phys_page,log_page);
/* Check for too high physical page */
if (phys_page>=EMM_MAX_PHYS) return EMM_ILL_PHYS;
/* Check for valid handle */
if (!ValidHandle(handle)) return EMM_INVALID_HANDLE;
/* Check to do unmapping or mappning */
if (log_page<emm_handles[handle].pages) {
/* Mapping it is */
emm_mappings[phys_page].handle=handle;
emm_mappings[phys_page].page=log_page;
MemHandle memh=MEM_NextHandleAt(emm_handles[handle].mem,log_page*4);;
for (Bitu i=0;i<4;i++) {
PAGING_MapPage(EMM_PAGEFRAME4K+phys_page*4+i,memh);
memh=MEM_NextHandle(memh);
}
PAGING_ClearTLB();
return EMM_NO_ERROR;
} else if (log_page==NULL_PAGE) {
/* Unmapping it is */
emm_mappings[phys_page].handle=NULL_HANDLE;
emm_mappings[phys_page].page=NULL_PAGE;
for (Bitu i=0;i<4;i++)
PAGING_MapPage(EMM_PAGEFRAME4K+phys_page*4+i,EMM_PAGEFRAME4K+phys_page*4+i);
PAGING_ClearTLB();
return EMM_NO_ERROR;
} else {
/* Illegal logical page it is */
return EMM_LOG_OUT_RANGE;
}
}
static Bit8u EMM_ReleaseMemory(Bit16u handle) {
/* Check for valid handle */
if (!ValidHandle(handle)) return EMM_INVALID_HANDLE;
MEM_ReleasePages(emm_handles[handle].mem);
/* Reset handle */
emm_handles[handle].mem=0;
emm_handles[handle].pages=NULL_HANDLE;
emm_handles[handle].saved_page_map=false;
memset(&emm_handles[handle].name,0,8);
return EMM_NO_ERROR;
}
static Bit8u EMM_SavePageMap(Bit16u handle) {
/* Check for valid handle */
if (handle>=EMM_MAX_HANDLES || emm_handles[handle].pages==NULL_HANDLE) return EMM_INVALID_HANDLE;
/* Check for previous save */
if (emm_handles[handle].saved_page_map) return EMM_PAGE_MAP_SAVED;
/* Copy the mappings over */
for (Bitu i=0;i<EMM_MAX_PHYS;i++) {
emm_handles[handle].page_map[i].page=emm_mappings[i].page;
emm_handles[handle].page_map[i].handle=emm_mappings[i].handle;
}
emm_handles[handle].saved_page_map=true;
return EMM_NO_ERROR;
}
static Bit8u EMM_RestoreMappingTable(void) {
Bit8u result;
/* Move through the mappings table and setup mapping accordingly */
for (Bitu i=0;i<EMM_MAX_PHYS;i++) {
result=EMM_MapPage(i,emm_mappings[i].handle,emm_mappings[i].page);
}
return EMM_NO_ERROR;
}
static Bit8u EMM_RestorePageMap(Bit16u handle) {
/* Check for valid handle */
if (handle>=EMM_MAX_HANDLES || emm_handles[handle].pages==NULL_HANDLE) return EMM_INVALID_HANDLE;
/* Check for previous save */
if (!emm_handles[handle].saved_page_map) return EMM_INVALID_HANDLE;
/* Restore the mappings */
emm_handles[handle].saved_page_map=false;
for (Bitu i=0;i<EMM_MAX_PHYS;i++) {
emm_mappings[i].page=emm_handles[handle].page_map[i].page;
emm_mappings[i].handle=emm_handles[handle].page_map[i].handle;
}
return EMM_RestoreMappingTable();
}
static Bit8u EMM_GetPagesForAllHandles(PhysPt table,Bit16u & handles) {
handles=0;
for (Bit16u i=0;i<EMM_MAX_HANDLES;i++) {
if (emm_handles[i].pages!=NULL_HANDLE) {
handles++;
mem_writew(table,i);
mem_writew(table+2,emm_handles[i].pages);
table+=4;
}
}
return EMM_NO_ERROR;
}
static Bit8u EMM_PartialPageMapping(void) {
PhysPt list,data;Bit16u count;
switch (reg_al) {
case 0x00: /* Save Partial Page Map */
list = SegPhys(ds)+reg_si;
data = SegPhys(es)+reg_di;
count=mem_readw(list);list+=2;
mem_writew(data,count);data+=2;
for (;count>0;count--) {
Bit16u page=mem_readw(list);list+=2;
if ((page<EMM_PAGEFRAME) || (page>=EMM_PAGEFRAME+0x1000)) return EMM_ILL_PHYS;
page = (page-EMM_PAGEFRAME) / (EMM_PAGE_SIZE>>4);
mem_writew(data,page);data+=2;
MEM_BlockWrite(data,&emm_mappings[page],sizeof(EMM_Mapping));
data+=sizeof(EMM_Mapping);
}
break;
case 0x01: /* Restore Partial Page Map */
data = SegPhys(ds)+reg_si;
count= mem_readw(data);data+=2;
for (;count>0;count--) {
Bit16u page=mem_readw(data);data+=2;
if (page>=EMM_MAX_PHYS) return EMM_ILL_PHYS;
MEM_BlockRead(data,&emm_mappings[page],sizeof(EMM_Mapping));
data+=sizeof(EMM_Mapping);
}
return EMM_RestoreMappingTable();
break;
case 0x02: /* Get Partial Page Map Array Size */
reg_al=2+reg_bx*(2+sizeof(EMM_Mapping));
break;
default:
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X Subfunction %2X not supported",reg_ah,reg_al);
return EMM_FUNC_NOSUP;
}
return EMM_NO_ERROR;
}
static Bit8u HandleNameSearch(void) {
char name[9];
Bit16u handle=0;PhysPt data;
switch (reg_al) {
case 0x00: /* Get all handle names */
reg_al=0;data=SegPhys(es)+reg_di;
for (handle=0;handle<EMM_MAX_HANDLES;handle++) {
if (emm_handles[handle].pages!=NULL_HANDLE) {
reg_al++;
mem_writew(data,handle);
MEM_BlockWrite(data+2,emm_handles[handle].name,8);
data+=10;
}
}
break;
case 0x01: /* Search for a handle name */
MEM_StrCopy(SegPhys(ds)+reg_si,name,8);name[8]=0;
for (handle=0;handle<EMM_MAX_HANDLES;handle++) {
if (emm_handles[handle].pages!=NULL_HANDLE) {
if (!strncmp(name,emm_handles[handle].name,8)) {
reg_dx=handle;
return EMM_NO_ERROR;
}
}
}
return EMM_NOT_FOUND;
break;
case 0x02: /* Get Total number of handles */
reg_bx=EMM_MAX_HANDLES;
break;
default:
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X Subfunction %2X not supported",reg_ah,reg_al);
return EMM_FUNC_NOSUP;
}
return EMM_NO_ERROR;
}
static Bit8u GetSetHandleName(void) {
Bit16u handle=reg_dx;
switch (reg_al) {
case 0x00: /* Get Handle Name */
if (handle>=EMM_MAX_HANDLES || emm_handles[handle].pages==NULL_HANDLE) return EMM_INVALID_HANDLE;
MEM_BlockWrite(SegPhys(es)+reg_di,emm_handles[handle].name,8);
break;
case 0x01: /* Set Handle Name */
if (handle>=EMM_MAX_HANDLES || emm_handles[handle].pages==NULL_HANDLE) return EMM_INVALID_HANDLE;
MEM_BlockRead(SegPhys(es)+reg_di,emm_handles[handle].name,8);
break;
default:
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X Subfunction %2X not supported",reg_ah,reg_al);
return EMM_FUNC_NOSUP;
}
return EMM_NO_ERROR;
}
static void LoadMoveRegion(PhysPt data,MoveRegion & region) {
region.bytes=mem_readd(data+0x0);
region.src_type=mem_readb(data+0x4);
region.src_handle=mem_readw(data+0x5);
region.src_offset=mem_readw(data+0x7);
region.src_page_seg=mem_readw(data+0x9);
region.dest_type=mem_readb(data+0xb);
region.dest_handle=mem_readw(data+0xc);
region.dest_offset=mem_readw(data+0xe);
region.dest_page_seg=mem_readw(data+0x10);
}
static Bit8u MemoryRegion(void) {
MoveRegion region;
Bit8u buf_src[MEM_PAGE_SIZE];
Bit8u buf_dest[MEM_PAGE_SIZE];
if (reg_al>1) {
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X Subfunction %2X not supported",reg_ah,reg_al);
return EMM_FUNC_NOSUP;
}
LoadMoveRegion(SegPhys(ds)+reg_si,region);
/* Parse the region for information */
PhysPt src_mem,dest_mem;
MemHandle src_handle,dest_handle;
Bitu src_off,dest_off;Bitu src_remain,dest_remain;
if (!region.src_type) {
src_mem=region.src_page_seg*16+region.src_offset;
} else {
if (!ValidHandle(region.src_handle)) return EMM_INVALID_HANDLE;
if ((emm_handles[region.src_handle].pages*EMM_PAGE_SIZE) < ((region.src_page_seg*EMM_PAGE_SIZE)+region.src_offset+region.bytes)) return EMM_LOG_OUT_RANGE;
src_handle=emm_handles[region.src_handle].mem;
Bitu pages=region.src_page_seg*4+(region.src_offset/MEM_PAGE_SIZE);
for (;pages>0;pages--) src_handle=MEM_NextHandle(src_handle);
src_off=region.src_offset&(MEM_PAGE_SIZE-1);
src_remain=MEM_PAGE_SIZE-src_off;
}
if (!region.dest_type) {
dest_mem=region.dest_page_seg*16+region.dest_offset;
} else {
if (!ValidHandle(region.dest_handle)) return EMM_INVALID_HANDLE;
if (emm_handles[region.dest_handle].pages*EMM_PAGE_SIZE < (region.dest_page_seg*EMM_PAGE_SIZE)+region.dest_offset+region.bytes) return EMM_LOG_OUT_RANGE;
dest_handle=emm_handles[region.dest_handle].mem;
Bitu pages=region.dest_page_seg*4+(region.dest_offset/MEM_PAGE_SIZE);
for (;pages>0;pages--) dest_handle=MEM_NextHandle(dest_handle);
dest_off=region.dest_offset&(MEM_PAGE_SIZE-1);
dest_remain=MEM_PAGE_SIZE-dest_off;
}
Bitu toread;
while (region.bytes>0) {
if (region.bytes>MEM_PAGE_SIZE) toread=MEM_PAGE_SIZE;
else toread=region.bytes;
/* Read from the source */
if (!region.src_type) {
MEM_BlockRead(src_mem,buf_src,toread);
} else {
if (toread<src_remain) {
MEM_BlockRead((src_handle*MEM_PAGE_SIZE)+src_off,buf_src,toread);
} else {
MEM_BlockRead((src_handle*MEM_PAGE_SIZE)+src_off,buf_src,src_remain);
MEM_BlockRead((MEM_NextHandle(src_handle)*MEM_PAGE_SIZE),&buf_src[src_remain],toread-src_remain);
}
}
/* Check for a move */
if (reg_al==1) {
/* Read from the destination */
if (!region.dest_type) {
MEM_BlockRead(dest_mem,buf_dest,toread);
} else {
if (toread<dest_remain) {
MEM_BlockRead((dest_handle*MEM_PAGE_SIZE)+dest_off,buf_dest,toread);
} else {
MEM_BlockRead((dest_handle*MEM_PAGE_SIZE)+dest_off,buf_dest,dest_remain);
MEM_BlockRead((MEM_NextHandle(dest_handle)*MEM_PAGE_SIZE),&buf_dest[dest_remain],toread-dest_remain);
}
}
/* Write to the source */
if (!region.src_type) {
MEM_BlockWrite(src_mem,buf_dest,toread);
} else {
if (toread<src_remain) {
MEM_BlockWrite((src_handle*MEM_PAGE_SIZE)+src_off,buf_dest,toread);
} else {
MEM_BlockWrite((src_handle*MEM_PAGE_SIZE)+src_off,buf_dest,src_remain);
MEM_BlockWrite((MEM_NextHandle(src_handle)*MEM_PAGE_SIZE),&buf_dest[src_remain],toread-src_remain);
}
}
}
/* Write to the destination */
if (!region.dest_type) {
MEM_BlockWrite(dest_mem,buf_src,toread);
} else {
if (toread<dest_remain) {
MEM_BlockWrite((dest_handle*MEM_PAGE_SIZE)+dest_off,buf_src,toread);
} else {
MEM_BlockWrite((dest_handle*MEM_PAGE_SIZE)+dest_off,buf_src,dest_remain);
MEM_BlockWrite((MEM_NextHandle(dest_handle)*MEM_PAGE_SIZE),&buf_src[dest_remain],toread-dest_remain);
}
}
/* Advance the pointers */
if (!region.src_type) src_mem+=toread;
else src_handle=MEM_NextHandle(src_handle);
if (!region.dest_type) dest_mem+=toread;
else dest_handle=MEM_NextHandle(dest_handle);
region.bytes-=toread;
}
return EMM_NO_ERROR;
}
static Bitu INT67_Handler(void) {
Bitu i;
switch (reg_ah) {
case 0x40: /* Get Status */
reg_ah=EMM_NO_ERROR;
break;
case 0x41: /* Get PageFrame Segment */
reg_bx=EMM_PAGEFRAME;
reg_ah=EMM_NO_ERROR;
break;
case 0x42: /* Get number of pages */
reg_dx=MEM_TotalPages()/4; //Not entirely correct but okay
reg_bx=EMM_GetFreePages();
reg_ah=EMM_NO_ERROR;
break;
case 0x43: /* Get Handle and Allocate Pages */
reg_ah=EMM_AllocateMemory(reg_bx,reg_dx);
break;
case 0x44: /* Map Expanded Memory Page */
reg_ah=EMM_MapPage(reg_al,reg_dx,reg_bx);
break;
case 0x45: /* Release handle and free pages */
reg_ah=EMM_ReleaseMemory(reg_dx);
break;
case 0x46: /* Get EMM Version */
reg_ah=EMM_NO_ERROR;
reg_al=EMM_VERSION;
break;
case 0x47: /* Save Page Map */
reg_ah=EMM_SavePageMap(reg_dx);
break;
case 0x48: /* Restore Page Map */
reg_ah=EMM_RestorePageMap(reg_dx);
break;
case 0x4b: /* Get Handle Count */
reg_bx=0;
for (i=0;i<EMM_MAX_HANDLES;i++) if (emm_handles[i].pages!=NULL_HANDLE) reg_bx++;
reg_ah=EMM_NO_ERROR;
break;
case 0x4c: /* Get Pages for one Handle */
if (!ValidHandle(reg_dx)) {reg_ah=EMM_INVALID_HANDLE;break;}
reg_bx=emm_handles[reg_dx].pages;
reg_ah=EMM_NO_ERROR;
break;
case 0x4d: /* Get Pages for all Handles */
reg_ah=EMM_GetPagesForAllHandles(SegPhys(es)+reg_di,reg_bx);
break;
case 0x4e: /*Save/Restore Page Map */
switch (reg_al) {
case 0x00: /* Save Page Map */
MEM_BlockWrite(SegPhys(es)+reg_di,emm_mappings,sizeof(emm_mappings));
reg_ah=EMM_NO_ERROR;
break;
case 0x01: /* Restore Page Map */
MEM_BlockRead(SegPhys(ds)+reg_si,emm_mappings,sizeof(emm_mappings));
reg_ah=EMM_RestoreMappingTable();
break;
case 0x02: /* Save and Restore Page Map */
MEM_BlockWrite(SegPhys(es)+reg_di,emm_mappings,sizeof(emm_mappings));
MEM_BlockRead(SegPhys(ds)+reg_si,emm_mappings,sizeof(emm_mappings));
reg_ah=EMM_RestoreMappingTable();
break;
case 0x03: /* Get Page Map Array Size */
reg_al=sizeof(emm_mappings);
reg_ah=EMM_NO_ERROR;
break;
default:
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X Subfunction %2X not supported",reg_ah,reg_al);
reg_ah=EMM_FUNC_NOSUP;
break;
}
break;
case 0x4f: /* Save/Restore Partial Page Map */
reg_ah=EMM_PartialPageMapping();
break;
case 0x50: /* Map/Unmap multiple handle pages */
reg_ah = EMM_NO_ERROR;
switch (reg_al) {
case 0x00: // use physical page numbers
{ PhysPt data = SegPhys(ds)+reg_si;
for (int i=0; i<reg_cx; i++) {
Bit16u logPage = mem_readw(data); data+=2;
Bit16u physPage = mem_readw(data); data+=2;
reg_ah = EMM_MapPage(physPage,reg_dx,logPage);
if (reg_ah!=EMM_NO_ERROR) break;
};
} break;
case 0x01: // use segment address
{ PhysPt data = SegPhys(ds)+reg_si;
for (int i=0; i<reg_cx; i++) {
Bit16u logPage = mem_readw(data); data+=2;
Bit16u physPage = (mem_readw(data)-EMM_PAGEFRAME)/(0x1000/EMM_MAX_PHYS); data+=2;
reg_ah = EMM_MapPage(physPage,reg_dx,logPage);
if (reg_ah!=EMM_NO_ERROR) break;
};
}
break;
}
break;
case 0x51: /* Reallocate Pages */
reg_ah=EMM_ReallocatePages(reg_dx,reg_bx);
break;
case 0x53: // Set/Get Handlename
reg_ah=GetSetHandleName();
break;
case 0x54: /* Handle Functions */
reg_ah=HandleNameSearch();
break;
case 0x57: /* Memory region */
reg_ah=MemoryRegion();
if (reg_ah) LOG(LOG_MISC,LOG_ERROR)("EMS:Function 57 move failed");
break;
case 0x58: // Get mappable physical array address array
if (reg_al==0x00) {
PhysPt data = SegPhys(es)+reg_di;
Bit16u step = 0x1000 / EMM_MAX_PHYS;
for (Bit16u i=0; i<EMM_MAX_PHYS; i++) {
mem_writew(data,EMM_PAGEFRAME+step*i); data+=2;
mem_writew(data,i); data+=2;
};
};
// Set number of pages
reg_cx = EMM_MAX_PHYS;
reg_ah = EMM_NO_ERROR;
break;
case 0xDE: /* VCPI Functions */
LOG(LOG_MISC,LOG_ERROR)("EMS:VCPI Call %2X not supported",reg_al);
reg_ah=EMM_FUNC_NOSUP;
break;
default:
LOG(LOG_MISC,LOG_ERROR)("EMS:Call %2X not supported",reg_ah);
reg_ah=EMM_FUNC_NOSUP;
break;
}
return CBRET_NONE;
}
static Bitu INT4B_Handler() {
switch (reg_ah) {
case 0x81:
CALLBACK_SCF(true);
reg_ax=0x1;
break;
default:
LOG(LOG_MISC,LOG_WARN)("Unhandled interrupt 4B function %x",reg_ah);
break;
}
return CBRET_NONE;
}
void EMS_Init(Section* sec) {
/* Virtual DMA interrupt callback */
call_vdma=CALLBACK_Allocate();
CALLBACK_Setup(call_vdma,&INT4B_Handler,CB_IRET);
RealSetVec(0x4b,CALLBACK_RealPointer(call_vdma));
Section_prop * section=static_cast<Section_prop *>(sec);
if (!section->Get_bool("ems")) return;
BIOS_ZeroExtendedSize();
call_int67=CALLBACK_Allocate();
CALLBACK_Setup(call_int67,&INT67_Handler,CB_IRET);
/* Register the ems device */
DOS_Device * newdev = new device_EMM();
DOS_AddDevice(newdev);
/* Add a little hack so it appears that there is an actual ems device installed */
char * emsname="EMMXXXX0";
Bit16u seg=DOS_GetMemory(2); //We have 32 bytes
MEM_BlockWrite(PhysMake(seg,0xa),emsname,strlen(emsname)+1);
/* Copy the callback piece into the beginning, and set the interrupt vector to it*/
char buf[16];
MEM_BlockRead(PhysMake(CB_SEG,call_int67<<4),buf,0xa);
MEM_BlockWrite(PhysMake(seg,0),buf,0xa);
RealSetVec(0x67,RealMake(seg,0));
/* Clear handle and page tables */
Bitu i;
for (i=0;i<EMM_MAX_HANDLES;i++) {
emm_handles[i].mem=0;
emm_handles[i].pages=NULL_HANDLE;
memset(&emm_handles[i].name,0,8);
}
for (i=0;i<EMM_MAX_PHYS;i++) {
emm_mappings[i].page=NULL_PAGE;
emm_mappings[i].handle=NULL_HANDLE;
}
}
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