sys/src/9/pc/vgavesa.c

   1 /*
   2  * vga driver using just vesa bios to set up.
   3  */
   4 #include "u.h"
   5 #include "../port/lib.h"
   6 #include "mem.h"
   7 #include "dat.h"
   8 #include "fns.h"
   9 #include "io.h"
  10 #include "../port/error.h"
  11
  12 #define Ureg Ureg386
  13 #include "/386/include/ureg.h"
  14 typedef struct Ureg386 Ureg386;
  15
  16 #define Image   IMAGE
  17 #include <draw.h>
  18 #include <memdraw.h>
  19 #include <cursor.h>
  20 #include "screen.h"
  21
  22 enum {
  23         Cdisable = 0,
  24         Cenable,
  25         Cblank,
  26
  27         RealModeBuf = 0x9000,
  28 };
  29
  30 static uchar modebuf[0x1000];
  31 static Chan *creg, *cmem;
  32 static QLock vesaq;
  33 static Rendez vesar;
  34 static int vesactl;
  35
  36 #define WORD(p) ((p)[0] | ((p)[1]<<8))
  37 #define LONG(p) ((p)[0] | ((p)[1]<<8) | ((p)[2]<<16) | ((p)[3]<<24))
  38 #define PWORD(p, v) (p)[0] = (v); (p)[1] = (v)>>8
  39 #define PLONG(p, v) (p)[0] = (v); (p)[1] = (v)>>8; (p)[2] = (v)>>16; (p)[3] = (v)>>24
  40
  41 static uchar*
  42 vbesetup(Ureg386 *u, int ax)
  43 {
  44         memset(modebuf, 0, sizeof modebuf);
  45         memset(u, 0, sizeof *u);
  46         u->ax = ax;
  47         u->es = (RealModeBuf>>4)&0xF000;
  48         u->di = RealModeBuf&0xFFFF;
  49         return modebuf;
  50 }
  51
  52 static void
  53 vbecall(Ureg386 *u)
  54 {
  55         if(devtab[cmem->type]->write(cmem, modebuf, sizeof(modebuf), RealModeBuf) != sizeof(modebuf))
  56                 error("write modebuf");
  57         u->trap = 0x10;
  58         if(devtab[creg->type]->write(creg, u, sizeof(*u), 0) != sizeof(*u))
  59                 error("write ureg");
  60         if(devtab[creg->type]->read(creg, u, sizeof(*u), 0) != sizeof(*u))
  61                 error("read ureg");
  62         if((u->ax&0xFFFF) != 0x004F)
  63                 error("vesa bios error");
  64         if(devtab[cmem->type]->read(cmem, modebuf, sizeof(modebuf), RealModeBuf) != sizeof(modebuf))
  65                 error("read modebuf");
  66 }
  67
  68 static void
  69 vbecheck(void)
  70 {
  71         Ureg386 u;
  72         uchar *p;
  73
  74         p = vbesetup(&u, 0x4F00);
  75         strcpy((char*)p, "VBE2");
  76         vbecall(&u);
  77         if(memcmp((char*)p, "VESA", 4) != 0)
  78                 error("bad vesa signature");
  79         if(p[5] < 2)
  80                 error("bad vesa version");
  81 }
  82
  83 static int
  84 vbegetmode(void)
  85 {
  86         Ureg386 u;
  87
  88         vbesetup(&u, 0x4F03);
  89         vbecall(&u);
  90         return u.bx;
  91 }
  92
  93 static uchar*
  94 vbemodeinfo(int mode)
  95 {
  96         uchar *p;
  97         Ureg386 u;
  98
  99         p = vbesetup(&u, 0x4F01);
 100         u.cx = mode;
 101         vbecall(&u);
 102         return p;
 103 }
 104
 105 static void
 106 vesalinear(VGAscr *scr, int, int)
 107 {
 108         int i, mode, size, havesize;
 109         ulong paddr;
 110         Pcidev *pci;
 111         uchar *p;
 112
 113         vbecheck();
 114         mode = vbegetmode();
 115         /*
 116          * bochs loses the top bits - cannot use this
 117         if((mode&(1<<14)) == 0)
 118                 error("not in linear graphics mode");
 119          */
 120         mode &= 0x3FFF;
 121         p = vbemodeinfo(mode);
 122         if(!(WORD(p+0) & (1<<4)))
 123                 error("not in VESA graphics mode");
 124         if(!(WORD(p+0) & (1<<7)))
 125                 error("not in linear graphics mode");
 126
 127         paddr = LONG(p+40);
 128         size = WORD(p+20)*WORD(p+16);
 129
 130         /*
 131          * figure out max size of memory so that we have
 132          * enough if the screen is resized.
 133          */
 134         pci = nil;
 135         havesize = 0;
 136         while(!havesize && (pci = pcimatch(pci, 0, 0)) != nil){
 137                 if(pci->ccrb != Pcibcdisp)
 138                         continue;
 139                 for(i=0; i<nelem(pci->mem); i++){
 140                         ulong a, e;
 141
 142                         if(pci->mem[i].bar&1)   /* not memory */
 143                                 continue;
 144                         a = pci->mem[i].bar & ~0xF;
 145                         e = a + pci->mem[i].size;
 146                         if(paddr >= a && (paddr+size) <= e){
 147                                 size = e - paddr;
 148                                 havesize = 1;
 149                                 break;
 150                         }
 151                 }
 152         }
 153
 154         /* no pci - heuristic guess */
 155         if(!havesize)
 156                 if(size < 4*1024*1024)
 157                         size = 4*1024*1024;
 158                 else
 159                         size = ROUND(size, 1024*1024);
 160
 161         vgalinearaddr(scr, paddr, size);
 162         if(scr->apsize)
 163                 addvgaseg("vesascreen", scr->paddr, scr->apsize);
 164
 165         scr->softscreen = 1;
 166 }
 167
 168 static int
 169 gotctl(void *arg)
 170 {
 171         return vesactl != *((int*)arg);
 172 }
 173
 174 static void
 175 vesaproc(void*)
 176 {
 177         Ureg386 u;
 178         int ctl;
 179
 180         ctl = Cenable;
 181         while(ctl != Cdisable){
 182                 if(!waserror()){
 183                         sleep(&vesar, gotctl, &ctl);
 184                         ctl = vesactl;
 185
 186                         vbesetup(&u, 0x4f10);
 187                         if(ctl == Cblank)
 188                                 u.bx = 0x0101;
 189                         else
 190                                 u.bx = 0x0001;
 191
 192                         /*
 193                          * dont wait forever here. some BIOS get stuck
 194                          * in i/o poll loop after blank/unblank for some
 195                          * reason. (Thinkpad A22p)
 196                          */
 197                         procalarm(10000);
 198                         vbecall(&u);
 199
 200                         poperror();
 201                 }
 202                 procalarm(0);
 203                 up->notepending = 0;
 204         }
 205         cclose(cmem);
 206         cclose(creg);
 207         cmem = creg = nil;
 208         qunlock(&vesaq);
 209
 210         pexit("", 1);
 211 }
 212
 213 static void
 214 vesaenable(VGAscr *)
 215 {
 216         eqlock(&vesaq);
 217         if(waserror()){
 218                 qunlock(&vesaq);
 219                 nexterror();
 220         }
 221         cmem = namec("/dev/realmodemem", Aopen, ORDWR, 0);
 222         if(waserror()){
 223                 cclose(cmem);
 224                 cmem = nil;
 225                 nexterror();
 226         }
 227         creg = namec("/dev/realmode", Aopen, ORDWR, 0);
 228         poperror();
 229         poperror();
 230
 231         vesactl = Cenable;
 232         kproc("vesa", vesaproc, nil);
 233 }
 234
 235 static void
 236 vesadisable(VGAscr *)
 237 {
 238         vesactl = Cdisable;
 239         wakeup(&vesar);
 240
 241         /* wait for vesaproc to finish */
 242         qlock(&vesaq);
 243         qunlock(&vesaq);
 244 }
 245
 246 static void
 247 vesablank(VGAscr *, int blank)
 248 {
 249         if(vesactl != Cdisable){
 250                 vesactl = blank ? Cblank : Cenable;
 251                 wakeup(&vesar);
 252         }
 253 }
 254
 255 static void
 256 vesadrawinit(VGAscr *scr)
 257 {
 258         scr->blank = vesablank;
 259 }
 260
 261 VGAdev vgavesadev = {
 262         "vesa",
 263         vesaenable,
 264         vesadisable,
 265         0,
 266         vesalinear,
 267         vesadrawinit,
 268 };