124 lines
3.5 KiB
C
124 lines
3.5 KiB
C
/*
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* 86Box A hypervisor and IBM PC system emulator that specializes in
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* running old operating systems and software designed for IBM
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* PC systems and compatibles from 1981 through fairly recent
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* system designs based on the PCI bus.
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*
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* Emulation of the IBM Expansion Unit (5161).
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*
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*
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*
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* Authors: Miran Grca, <mgrca8@gmail.com>
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*
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* Copyright 2016-2018 Miran Grca.
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*/
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <wchar.h>
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#include <86box/86box.h>
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#include <86box/device.h>
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#include <86box/io.h>
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#include <86box/apm.h>
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#include <86box/dma.h>
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#include <86box/mem.h>
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#include <86box/pci.h>
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#include <86box/timer.h>
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#include <86box/pit.h>
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#include <86box/plat_unused.h>
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#include <86box/port_92.h>
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#include <86box/machine.h>
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typedef struct ibm_5161_t {
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uint8_t regs[8];
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} ibm_5161_t;
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static void
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ibm_5161_out(uint16_t port, uint8_t val, void *priv)
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{
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ibm_5161_t *dev = (ibm_5161_t *) priv;
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dev->regs[port & 0x0007] = val;
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}
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static uint8_t
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ibm_5161_in(uint16_t port, void *priv)
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{
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const ibm_5161_t *dev = (ibm_5161_t *) priv;
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uint8_t ret = 0xff;
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ret = dev->regs[port & 0x0007];
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switch (port) {
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case 0x210: /* Write to latch expansion bus data (ED0-ED7) */
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/* Read to verify expansion bus data (ED0-ED7) */
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break;
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case 0x214: /* Write to latch data bus bits (DO - 07) */
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/* Read data bus bits (DO - D7) */
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break;
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case 0x211: /* Read high-order address bits (A8 - A 15) */
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case 0x215: /* Read high-order address bits (A8 - A 15) */
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ret = (get_last_addr() >> 8) & 0xff;
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break;
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case 0x212: /* Read low-order address bits (A0 - A7) */
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case 0x216: /* Read low-order address bits (A0 - A7) */
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ret = get_last_addr() & 0xff;
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break;
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case 0x213: /* Write 00 to disable expansion unit */
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/* Write 01 to enable expansion unit */
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/* Read status of expansion unit
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00 = enable/disable
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01 = wait-state request flag
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02-03 = not used
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04-07 = switch position
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1 = Off
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0 = On */
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ret = (dev->regs[3] & 0x01) | (((~(0xf - ((mem_size + isa_mem_size) >> 6))) & 0xf) << 4);
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break;
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default:
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break;
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}
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return ret;
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}
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static void
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ibm_5161_close(void *priv)
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{
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ibm_5161_t *dev = (ibm_5161_t *) priv;
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free(dev);
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}
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static void *
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ibm_5161_init(UNUSED(const device_t *info))
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{
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ibm_5161_t *dev = (ibm_5161_t *) calloc(1, sizeof(ibm_5161_t));
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/* Extender Card Registers */
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io_sethandler(0x0210, 0x0004,
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ibm_5161_in, NULL, NULL, ibm_5161_out, NULL, NULL, dev);
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/* Receiver Card Registers */
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io_sethandler(0x0214, 0x0003,
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ibm_5161_in, NULL, NULL, ibm_5161_out, NULL, NULL, dev);
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return dev;
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}
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const device_t ibm_5161_device = {
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.name = "IBM Expansion Unit (5161)",
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.internal_name = "ibm_5161",
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.flags = DEVICE_ISA,
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.local = 0,
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.init = ibm_5161_init,
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.close = ibm_5161_close,
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.reset = NULL,
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{ .available = NULL },
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.speed_changed = NULL,
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.force_redraw = NULL,
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.config = NULL
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};
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