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