86Box/src/video/vid_ics2494.c

/*
 * 86Box	A hypervisor and IBM PC system emulator that specializes in
 *		running old operating systems and software designed for IBM
 *		PC systems and compatibles from 1981 through fairly recent
 *		system designs based on the PCI bus.
 *
 *		This file is part of the 86Box distribution.
 *
 *		ICS2494 clock generator emulation.
 *
 *		Used by the AMI S3 924.
 *
 *
 *
 * Authors:	Miran Grca, <mgrca8@gmail.com>
 *
 *		Copyright 2020 Miran Grca.
 */
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <86box/86box.h>
#include <86box/device.h>


typedef struct ics2494_t
{
    float freq[16];
} ics2494_t;


#ifdef ENABLE_ics2494_LOG
int ics2494_do_log = ENABLE_ics2494_LOG;


static void
ics2494_log(const char *fmt, ...)
{
    va_list ap;

    if (ics2494_do_log) {
	va_start(ap, fmt);
	pclog_ex(fmt, ap);
	va_end(ap);
    }
}
#else
#define ics2494_log(fmt, ...)
#endif


float
ics2494_getclock(int clock, void *p)
{
    ics2494_t *ics2494 = (ics2494_t *) p;

    if (clock > 16)
	clock = 16;

    return ics2494->freq[clock];
}


static void *
ics2494_init(const device_t *info)
{
    ics2494_t *ics2494 = (ics2494_t *) malloc(sizeof(ics2494_t));
    memset(ics2494, 0, sizeof(ics2494_t));

    switch (info->local) {
	case 305:
		/* ICS2494A(N)-205 for S3 86C924 */
		ics2494->freq[0x0] =  25175000.0;
		ics2494->freq[0x1] =  28322000.0;
		ics2494->freq[0x2] =  40000000.0;
		ics2494->freq[0x3] =         0.0;
		ics2494->freq[0x4] =  50000000.0;
		ics2494->freq[0x5] =  77000000.0;
		ics2494->freq[0x6] =  36000000.0;
		ics2494->freq[0x7] =  44889000.0;
		ics2494->freq[0x8] = 130000000.0;
		ics2494->freq[0x9] = 120000000.0;
		ics2494->freq[0xa] =  80000000.0;
		ics2494->freq[0xb] =  31500000.0;
		ics2494->freq[0xc] = 110000000.0;
		ics2494->freq[0xd] =  65000000.0;
		ics2494->freq[0xe] =  75000000.0;
		ics2494->freq[0xf] =  94500000.0;
		break;
    }

    return ics2494;
}


static void
ics2494_close(void *priv)
{
    ics2494_t *ics2494 = (ics2494_t *) priv;

    if (ics2494)
	free(ics2494);
}


const device_t ics2494an_305_device =
{
        "ICS2494AN-305 Clock Generator",
        0, 305,
        ics2494_init, ics2494_close,
	NULL, { NULL }, NULL, NULL
};