include/pci_bus.h

/*
 *  Copyright (C) 2002-2020  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 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.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#ifndef DOSBOX_PCI_H
#define DOSBOX_PCI_H

#define PCI_MAX_PCIBUSSES                   255
#define PCI_MAX_PCIDEVICES                  32
#define PCI_MAX_PCIFUNCTIONS            8

class PCI_Device {
public:
        /* configuration space */
        unsigned char config[256];
        unsigned char config_writemask[256];

        PCI_Device(Bit16u vendor, Bit16u device);
        virtual ~PCI_Device();

        /* configuration space assistant functions */

        Bit16u getDeviceID() {
                return host_readw(config + 0x02);
        }
        void setDeviceID(const Bit16u device) {
                return host_writew(config + 0x02,device);
        }

        Bit16u getVendorID() {
                return host_readw(config + 0x00);
        }
        void setVendorID(const Bit16u vendor) {
                return host_writew(config + 0x00,vendor);
        }

        /* configuration space I/O */
        virtual void config_write(Bit8u regnum,Bitu iolen,Bit32u value) {
                if (iolen == 1) {
            const unsigned char mask = config_writemask[regnum];
            const unsigned char nmask = ~mask;
                        /* only allow writing to the bits marked off as writeable */
                        config[regnum] = (config[regnum] & nmask) + ((unsigned char)value & mask);
                }
                else if (iolen == 4 && (regnum&3) == 2) { /* unaligned DWORD write (subdividable into two WORD writes) */
                        config_write(regnum,2,value&0xFFFF);
                        config_write(regnum+2,2,value>>16);
                }
                else {
                        /* subdivide into 8-bit I/O */
                        /* NTS: If I recall, this virtual function call means that we'll call the
                         *      C++ subclass's config_write() NOT our own--right? */
                        for (Bitu i=0;i < iolen;i++) {
                                config_write((Bit8u)(regnum+i),1,value&0xFF);
                                value >>= 8U;
                        }
                }
        }
        virtual Bit32u config_read(Bit8u regnum,Bitu iolen) {
                /* subdivide into 8-bit I/O */
                Bit32u v=0;

                if (iolen == 1)
                        return config[regnum];
                else if (iolen == 4 && (regnum&3) == 2) { /* unaligned DWORD read (subdividable into two WORD reads) */
                        v = config_read(regnum,2);
                        v += config_read(regnum+2,2) << 16;
                }
                else {
                        /* NTS: If I recall, this virtual function call means that we'll call the
                         *      C++ subclass's config_read() NOT our own--right? */
                        for (Bitu i=0;i < iolen;i++)
                                v += ((config_read((Bit8u)(regnum+i),1)&0xFF) << ((iolen-i-1)*8));
                }

                return v;
        }
};

bool PCI_IsInitialized();

void PCI_AddSVGAS3_Device(void);
void PCI_RemoveSVGAS3_Device(void);

void PCI_AddSST_Device(Bitu type);
void PCI_RemoveSST_Device(void);

RealPt PCI_GetPModeInterface(void);

#endif