freebsd-dev/usr.sbin/pcvt/set2061/ICD2061Aalt.c
1995-05-30 03:57:47 +00:00

298 lines
6.0 KiB
C

/*
* This code is derived from code available from the STB bulletin board
*/
/* $XFree86: mit/server/ddx/x386/common_hw/ICD2061Aalt.c,v 2.6 1994/04/15 05:10:30 dawes Exp $ */
#ifndef KERNEL
#include "compiler.h"
#else
#define GCCUSESGAS
#define PCVT_STANDALONE 1
#endif
#define SEQREG 0x03C4
#define MISCREG 0x03C2
#define MISCREAD 0x03CC
double fref = 14.31818 * 2.0;
char ascclk[] = "VIDEO CLOCK ?";
unsigned short clknum;
unsigned short vlbus_flag;
unsigned short card;
unsigned short crtcaddr;
unsigned short clockreg;
static double range[15] = {50.0, 51.0, 53.2, 58.5, 60.7, 64.4, 66.8, 73.5,
75.6, 80.9, 83.2, 91.5, 100.0, 120.0, 120.0};
#ifdef __STDC__
static double genratio(unsigned int *p, unsigned int *q, double tgt);
static double f(unsigned int p, unsigned int q, double basefreq);
#if 0
static void prtbinary(unsigned int size, unsigned int val);
#endif
static void wait_vb();
static void wrt_clk_bit(unsigned int value);
static void init_clock(unsigned long setup, unsigned short crtcport);
#else
static double genratio();
static double f();
#if 0
static void prtbinary();
#endif
static void wait_vb();
static void wrt_clk_bit();
static void init_clock();
#endif
void AltICD2061SetClock(frequency, select)
register long frequency; /* in Hz */
int select;
{
unsigned int m, mval, ival;
int i;
long dwv;
double realval;
double freq, fvco;
double dev, devx;
double delta, deltax;
unsigned int p, q;
unsigned int bestp, bestq;
unsigned char tmp;
crtcaddr=(inb(0x3CC) & 0x01) ? 0x3D4 : 0x3B4;
outb(crtcaddr, 0x11); /* Unlock CRTC registers */
tmp = inb(crtcaddr + 1);
outb(crtcaddr + 1, tmp & ~0x80);
outw(crtcaddr, 0x4838); /* Unlock S3 register set */
outw(crtcaddr, 0xA039);
clknum = select;
freq = ((double)frequency)/1000000.0;
if (freq > range[14])
freq =range[14];
else if (freq <= 6.99)
freq = 7.0;
/*
* Calculate values to load into ICD 2061A clock chip to set frequency
*/
delta = 999.0;
dev = 999.0;
ival = 99;
mval = 99;
fvco = freq / 2;
for (m = 0; m < 8; m++) {
fvco *= 2.0;
for (i = 14; i >= 0; i--)
if (fvco >= range[i])
break;
if (i < 0)
continue;
if (i == 14)
break;
devx = (fvco - (range[i] + range[i+1])/2)/fvco;
if (devx < 0)
devx = -devx;
deltax = genratio(&p, &q, fvco);
if (delta < deltax)
continue;
if (deltax < delta || devx < dev) {
bestp = p;
bestq = q;
delta = deltax;
dev = devx;
ival = i;
mval = m;
}
}
fvco = fref;
for (m=0; m<mval; m++)
fvco /= 2.0;
realval = f(bestp, bestq, fvco);
dwv = ((((((long)ival << 7) | bestp) << 3) | mval) << 7) | bestq;
/*
* Write ICD 2061A clock chip
*/
init_clock(((unsigned long)dwv) | (((long)clknum) << 21), crtcaddr);
wait_vb();
wait_vb();
wait_vb();
wait_vb();
wait_vb();
wait_vb();
wait_vb(); /* 0.10 second delay... */
}
static double f(p, q, base)
unsigned int p;
unsigned int q;
double base;
{
return(base * (p + 3)/(q + 2));
}
static double genratio(p, q, tgt)
unsigned int *p;
unsigned int *q;
double tgt;
{
int k, m;
double test, mindiff;
unsigned int mmax;
mindiff = 999999999.0;
for (k = 13; k < 69; k++) { /* q={15..71}:Constraint 2 on page 14 */
m = 50.0*k/fref - 3;
if (m < 0)
m = 0;
mmax = 120*k/fref - 3; /* m..mmax is constraint 3 on page 14 */
if (mmax > 128)
mmax = 128;
while (m < mmax) {
test = f(m, k, fref) - tgt;
if (test < 0) test = -test;
if (mindiff > test) {
mindiff = test;
*p = m;
*q = k;
}
m++;
}
}
return (mindiff);
}
#if 0
static void prtbinary(size, val)
unsigned int size;
unsigned int val;
{
unsigned int mask;
int k;
mask = 1;
for (k=size; --k > 0 || mask <= val/2;)
mask <<= 1;
while (mask) {
fputc((mask&val)? '1': '0' , stderr);
mask >>= 1;
}
}
#endif
static void wait_vb()
{
while ((inb(crtcaddr+6) & 0x08) == 0)
;
while (inb(crtcaddr+6) & 0x08)
;
}
#ifdef __STDC__
static void init_clock(unsigned long setup, unsigned short crtcport)
#else
static void init_clock(setup, crtcport)
unsigned long setup;
unsigned short crtcport;
#endif
{
unsigned char nclk[2], clk[2];
unsigned short restore42;
unsigned short oldclk;
unsigned short bitval;
int i;
unsigned char c;
#ifndef PCVT_STANDALONE
(void)xf86DisableInterrupts();
#endif
oldclk = inb(0x3CC);
outb(crtcport, 0x42);
restore42 = inb(crtcport+1);
outw(0x3C4, 0x0100);
outb(0x3C4, 1);
c = inb(0x3C5);
outb(0x3C5, 0x20 | c);
outb(crtcport, 0x42);
outb(crtcport+1, 0x03);
outw(0x3C4, 0x0300);
nclk[0] = oldclk & 0xF3;
nclk[1] = nclk[0] | 0x08;
clk[0] = nclk[0] | 0x04;
clk[1] = nclk[0] | 0x0C;
outb(crtcport, 0x42);
i = inw(crtcport);
outw(0x3C4, 0x0100);
wrt_clk_bit(oldclk | 0x08);
wrt_clk_bit(oldclk | 0x0C);
for (i=0; i<5; i++) {
wrt_clk_bit(nclk[1]);
wrt_clk_bit(clk[1]);
}
wrt_clk_bit(nclk[1]);
wrt_clk_bit(nclk[0]);
wrt_clk_bit(clk[0]);
wrt_clk_bit(nclk[0]);
wrt_clk_bit(clk[0]);
for (i=0; i<24; i++) {
bitval = setup & 0x01;
setup >>= 1;
wrt_clk_bit(clk[1-bitval]);
wrt_clk_bit(nclk[1-bitval]);
wrt_clk_bit(nclk[bitval]);
wrt_clk_bit(clk[bitval]);
}
wrt_clk_bit(clk[1]);
wrt_clk_bit(nclk[1]);
wrt_clk_bit(clk[1]);
outb(0x3C4, 1);
c = inb(0x3C5);
outb(0x3C5, 0xDF & c);
outb(crtcport, 0x42);
outb(crtcport+1, restore42);
outb(0x3C2, oldclk);
outw(0x3C4, 0x0300);
#ifndef PCVT_STANDALONE
xf86EnableInterrupts();
#endif
}
static void wrt_clk_bit(value)
unsigned int value;
{
int j;
outb(0x3C2, value);
for (j=2; --j; )
inb(0x200);
}