sys/src/cmd/aux/vga/ics2494.c

   1 /*
   2  * Integrated Circuit Systems, Inc.
   3  * ICS2494[A] Dual Video/Memory Clock Generator.
   4  */
   5 #include <u.h>
   6 #include <libc.h>
   7 #include <bio.h>
   8
   9 #include "pci.h"
  10 #include "vga.h"
  11
  12 typedef struct {
  13         char*   name[2];
  14         ulong   frequency[16];
  15 } Pattern;
  16
  17 static Pattern patterns[] = {
  18         { "237", "304",
  19          50350000,  56644000,  65000000,  72000000,  80000000,  89800000,  63000000,  75000000,
  20          25175000,  28322000,  31500000,  36000000,  40000000,  44900000,  50000000,  65000000,
  21         },
  22
  23         { "324", 0,
  24          50350000,  56644000,  65000000,  72000000,  80000000,  89800000,  63000000,  75000000,
  25          83078000,  93463000, 100000000, 104000000, 108000000, 120000000, 130000000, 134700000,
  26         },
  27
  28         { 0,
  29         },
  30 };
  31
  32 static void
  33 init(Vga* vga, Ctlr* ctlr)
  34 {
  35         Pattern *pattern;
  36         char *p;
  37         int f, index, divisor, maxdivisor;
  38
  39         if(ctlr->flag & Finit)
  40                 return;
  41
  42         if(vga->f[0] == 0)
  43                 vga->f[0] = vga->mode->frequency;
  44
  45         if((p = strchr(ctlr->name, '-')) == 0)
  46                 error("%s: unknown pattern\n", ctlr->name);
  47         p++;
  48
  49         for(pattern = patterns; pattern->name[0]; pattern++){
  50                 if(strcmp(pattern->name[0], p) == 0)
  51                         break;
  52                 if(pattern->name[1] && strcmp(pattern->name[1], p) == 0)
  53                         break;
  54         }
  55         if(pattern->name[0] == 0)
  56                 error("%s: unknown pattern\n", ctlr->name);
  57
  58         maxdivisor = 1;
  59         if(vga->ctlr && (vga->ctlr->flag & Hclkdiv))
  60                 maxdivisor = 8;
  61         for(index = 0; index < 16; index++){
  62                 for(divisor = 1; divisor <= maxdivisor; divisor <<= 1){
  63                         f = vga->f[0] - pattern->frequency[index]/divisor;
  64                         if(f < 0)
  65                                 f = -f;
  66                         if(f < 1000000){
  67                                 /*vga->f = pattern->frequency[index];*/
  68                                 vga->d[0] = divisor;
  69                                 vga->i[0] = index;
  70
  71                                 ctlr->flag |= Finit;
  72                                 return;
  73                         }
  74                 }
  75         }
  76         error("%s: can't find frequency %ld\n", ctlr->name, vga->f[0]);
  77 }
  78
  79 Ctlr ics2494 = {
  80         "ics2494",                      /* name */
  81         0,                              /* snarf */
  82         0,                              /* options */
  83         init,                           /* init */
  84         0,                              /* load */
  85         0,                              /* dump */
  86 };
  87
  88 Ctlr ics2494a = {
  89         "ics2494a",                     /* name */
  90         0,                              /* snarf */
  91         0,                              /* options */
  92         init,                           /* init */
  93         0,                              /* load */
  94         0,                              /* dump */
  95 };