hw/milkymist-tmu2.c

   1 /*
   2  *  QEMU model of the Milkymist texture mapping unit.
   3  *
   4  *  Copyright (c) 2010 Michael Walle <michael@walle.cc>
   5  *  Copyright (c) 2010 Sebastien Bourdeauducq
   6  *                       <sebastien.bourdeauducq@lekernel.net>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  20  *
  21  *
  22  * Specification available at:
  23  *   http://www.milkymist.org/socdoc/tmu2.pdf
  24  *
  25  */
  26
  27 #include "hw/hw.h"
  28 #include "hw/sysbus.h"
  29 #include "trace.h"
  30 #include "qemu/error-report.h"
  31
  32 #include <X11/Xlib.h>
  33 #include <GL/gl.h>
  34 #include <GL/glx.h>
  35
  36 enum {
  37     R_CTL = 0,
  38     R_HMESHLAST,
  39     R_VMESHLAST,
  40     R_BRIGHTNESS,
  41     R_CHROMAKEY,
  42     R_VERTICESADDR,
  43     R_TEXFBUF,
  44     R_TEXHRES,
  45     R_TEXVRES,
  46     R_TEXHMASK,
  47     R_TEXVMASK,
  48     R_DSTFBUF,
  49     R_DSTHRES,
  50     R_DSTVRES,
  51     R_DSTHOFFSET,
  52     R_DSTVOFFSET,
  53     R_DSTSQUAREW,
  54     R_DSTSQUAREH,
  55     R_ALPHA,
  56     R_MAX
  57 };
  58
  59 enum {
  60     CTL_START_BUSY  = (1<<0),
  61     CTL_CHROMAKEY   = (1<<1),
  62 };
  63
  64 enum {
  65     MAX_BRIGHTNESS = 63,
  66     MAX_ALPHA      = 63,
  67 };
  68
  69 enum {
  70     MESH_MAXSIZE = 128,
  71 };
  72
  73 struct vertex {
  74     int x;
  75     int y;
  76 } QEMU_PACKED;
  77
  78 struct MilkymistTMU2State {
  79     SysBusDevice busdev;
  80     MemoryRegion regs_region;
  81     CharDriverState *chr;
  82     qemu_irq irq;
  83
  84     uint32_t regs[R_MAX];
  85
  86     Display *dpy;
  87     GLXFBConfig glx_fb_config;
  88     GLXContext glx_context;
  89 };
  90 typedef struct MilkymistTMU2State MilkymistTMU2State;
  91
  92 static const int glx_fbconfig_attr[] = {
  93     GLX_GREEN_SIZE, 5,
  94     GLX_GREEN_SIZE, 6,
  95     GLX_BLUE_SIZE, 5,
  96     None
  97 };
  98
  99 static int tmu2_glx_init(MilkymistTMU2State *s)
 100 {
 101     GLXFBConfig *configs;
 102     int nelements;
 103
 104     s->dpy = XOpenDisplay(NULL); /* FIXME: call XCloseDisplay() */
 105     if (s->dpy == NULL) {
 106         return 1;
 107     }
 108
 109     configs = glXChooseFBConfig(s->dpy, 0, glx_fbconfig_attr, &nelements);
 110     if (configs == NULL) {
 111         return 1;
 112     }
 113
 114     s->glx_fb_config = *configs;
 115     XFree(configs);
 116
 117     /* FIXME: call glXDestroyContext() */
 118     s->glx_context = glXCreateNewContext(s->dpy, s->glx_fb_config,
 119             GLX_RGBA_TYPE, NULL, 1);
 120     if (s->glx_context == NULL) {
 121         return 1;
 122     }
 123
 124     return 0;
 125 }
 126
 127 static void tmu2_gl_map(struct vertex *mesh, int texhres, int texvres,
 128         int hmeshlast, int vmeshlast, int ho, int vo, int sw, int sh)
 129 {
 130     int x, y;
 131     int x0, y0, x1, y1;
 132     int u0, v0, u1, v1, u2, v2, u3, v3;
 133     double xscale = 1.0 / ((double)(64 * texhres));
 134     double yscale = 1.0 / ((double)(64 * texvres));
 135
 136     glLoadIdentity();
 137     glTranslatef(ho, vo, 0);
 138     glEnable(GL_TEXTURE_2D);
 139     glBegin(GL_QUADS);
 140
 141     for (y = 0; y < vmeshlast; y++) {
 142         y0 = y * sh;
 143         y1 = y0 + sh;
 144         for (x = 0; x < hmeshlast; x++) {
 145             x0 = x * sw;
 146             x1 = x0 + sw;
 147
 148             u0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].x);
 149             v0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].y);
 150             u1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].x);
 151             v1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].y);
 152             u2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].x);
 153             v2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].y);
 154             u3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].x);
 155             v3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].y);
 156
 157             glTexCoord2d(((double)u0) * xscale, ((double)v0) * yscale);
 158             glVertex3i(x0, y0, 0);
 159             glTexCoord2d(((double)u1) * xscale, ((double)v1) * yscale);
 160             glVertex3i(x1, y0, 0);
 161             glTexCoord2d(((double)u2) * xscale, ((double)v2) * yscale);
 162             glVertex3i(x1, y1, 0);
 163             glTexCoord2d(((double)u3) * xscale, ((double)v3) * yscale);
 164             glVertex3i(x0, y1, 0);
 165         }
 166     }
 167
 168     glEnd();
 169 }
 170
 171 static void tmu2_start(MilkymistTMU2State *s)
 172 {
 173     int pbuffer_attrib[6] = {
 174         GLX_PBUFFER_WIDTH,
 175         0,
 176         GLX_PBUFFER_HEIGHT,
 177         0,
 178         GLX_PRESERVED_CONTENTS,
 179         True
 180     };
 181
 182     GLXPbuffer pbuffer;
 183     GLuint texture;
 184     void *fb;
 185     hwaddr fb_len;
 186     void *mesh;
 187     hwaddr mesh_len;
 188     float m;
 189
 190     trace_milkymist_tmu2_start();
 191
 192     /* Create and set up a suitable OpenGL context */
 193     pbuffer_attrib[1] = s->regs[R_DSTHRES];
 194     pbuffer_attrib[3] = s->regs[R_DSTVRES];
 195     pbuffer = glXCreatePbuffer(s->dpy, s->glx_fb_config, pbuffer_attrib);
 196     glXMakeContextCurrent(s->dpy, pbuffer, pbuffer, s->glx_context);
 197
 198     /* Fixup endianness. TODO: would it work on BE hosts? */
 199     glPixelStorei(GL_UNPACK_SWAP_BYTES, 1);
 200     glPixelStorei(GL_PACK_SWAP_BYTES, 1);
 201
 202     /* Row alignment */
 203     glPixelStorei(GL_UNPACK_ALIGNMENT, 2);
 204     glPixelStorei(GL_PACK_ALIGNMENT, 2);
 205
 206     /* Read the QEMU source framebuffer into an OpenGL texture */
 207     glGenTextures(1, &texture);
 208     glBindTexture(GL_TEXTURE_2D, texture);
 209     fb_len = 2*s->regs[R_TEXHRES]*s->regs[R_TEXVRES];
 210     fb = cpu_physical_memory_map(s->regs[R_TEXFBUF], &fb_len, 0);
 211     if (fb == NULL) {
 212         glDeleteTextures(1, &texture);
 213         glXMakeContextCurrent(s->dpy, None, None, NULL);
 214         glXDestroyPbuffer(s->dpy, pbuffer);
 215         return;
 216     }
 217     glTexImage2D(GL_TEXTURE_2D, 0, 3, s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 218             0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, fb);
 219     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 220
 221     /* Set up texturing options */
 222     /* WARNING:
 223      * Many cases of TMU2 masking are not supported by OpenGL.
 224      * We only implement the most common ones:
 225      *  - full bilinear filtering vs. nearest texel
 226      *  - texture clamping vs. texture wrapping
 227      */
 228     if ((s->regs[R_TEXHMASK] & 0x3f) > 0x20) {
 229         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 230         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 231     } else {
 232         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 233         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 234     }
 235     if ((s->regs[R_TEXHMASK] >> 6) & s->regs[R_TEXHRES]) {
 236         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
 237     } else {
 238         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 239     }
 240     if ((s->regs[R_TEXVMASK] >> 6) & s->regs[R_TEXVRES]) {
 241         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 242     } else {
 243         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 244     }
 245
 246     /* Translucency and decay */
 247     glEnable(GL_BLEND);
 248     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 249     m = (float)(s->regs[R_BRIGHTNESS] + 1) / 64.0f;
 250     glColor4f(m, m, m, (float)(s->regs[R_ALPHA] + 1) / 64.0f);
 251
 252     /* Read the QEMU dest. framebuffer into the OpenGL framebuffer */
 253     fb_len = 2 * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 254     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 0);
 255     if (fb == NULL) {
 256         glDeleteTextures(1, &texture);
 257         glXMakeContextCurrent(s->dpy, None, None, NULL);
 258         glXDestroyPbuffer(s->dpy, pbuffer);
 259         return;
 260     }
 261
 262     glDrawPixels(s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 263             GL_UNSIGNED_SHORT_5_6_5, fb);
 264     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 265     glViewport(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES]);
 266     glMatrixMode(GL_PROJECTION);
 267     glLoadIdentity();
 268     glOrtho(0.0, s->regs[R_DSTHRES], 0.0, s->regs[R_DSTVRES], -1.0, 1.0);
 269     glMatrixMode(GL_MODELVIEW);
 270
 271     /* Map the texture */
 272     mesh_len = MESH_MAXSIZE*MESH_MAXSIZE*sizeof(struct vertex);
 273     mesh = cpu_physical_memory_map(s->regs[R_VERTICESADDR], &mesh_len, 0);
 274     if (mesh == NULL) {
 275         glDeleteTextures(1, &texture);
 276         glXMakeContextCurrent(s->dpy, None, None, NULL);
 277         glXDestroyPbuffer(s->dpy, pbuffer);
 278         return;
 279     }
 280
 281     tmu2_gl_map((struct vertex *)mesh,
 282         s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 283         s->regs[R_HMESHLAST], s->regs[R_VMESHLAST],
 284         s->regs[R_DSTHOFFSET], s->regs[R_DSTVOFFSET],
 285         s->regs[R_DSTSQUAREW], s->regs[R_DSTSQUAREH]);
 286     cpu_physical_memory_unmap(mesh, mesh_len, 0, mesh_len);
 287
 288     /* Write back the OpenGL framebuffer to the QEMU framebuffer */
 289     fb_len = 2 * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 290     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 1);
 291     if (fb == NULL) {
 292         glDeleteTextures(1, &texture);
 293         glXMakeContextCurrent(s->dpy, None, None, NULL);
 294         glXDestroyPbuffer(s->dpy, pbuffer);
 295         return;
 296     }
 297
 298     glReadPixels(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 299             GL_UNSIGNED_SHORT_5_6_5, fb);
 300     cpu_physical_memory_unmap(fb, fb_len, 1, fb_len);
 301
 302     /* Free OpenGL allocs */
 303     glDeleteTextures(1, &texture);
 304     glXMakeContextCurrent(s->dpy, None, None, NULL);
 305     glXDestroyPbuffer(s->dpy, pbuffer);
 306
 307     s->regs[R_CTL] &= ~CTL_START_BUSY;
 308
 309     trace_milkymist_tmu2_pulse_irq();
 310     qemu_irq_pulse(s->irq);
 311 }
 312
 313 static uint64_t tmu2_read(void *opaque, hwaddr addr,
 314                           unsigned size)
 315 {
 316     MilkymistTMU2State *s = opaque;
 317     uint32_t r = 0;
 318
 319     addr >>= 2;
 320     switch (addr) {
 321     case R_CTL:
 322     case R_HMESHLAST:
 323     case R_VMESHLAST:
 324     case R_BRIGHTNESS:
 325     case R_CHROMAKEY:
 326     case R_VERTICESADDR:
 327     case R_TEXFBUF:
 328     case R_TEXHRES:
 329     case R_TEXVRES:
 330     case R_TEXHMASK:
 331     case R_TEXVMASK:
 332     case R_DSTFBUF:
 333     case R_DSTHRES:
 334     case R_DSTVRES:
 335     case R_DSTHOFFSET:
 336     case R_DSTVOFFSET:
 337     case R_DSTSQUAREW:
 338     case R_DSTSQUAREH:
 339     case R_ALPHA:
 340         r = s->regs[addr];
 341         break;
 342
 343     default:
 344         error_report("milkymist_tmu2: read access to unknown register 0x"
 345                 TARGET_FMT_plx, addr << 2);
 346         break;
 347     }
 348
 349     trace_milkymist_tmu2_memory_read(addr << 2, r);
 350
 351     return r;
 352 }
 353
 354 static void tmu2_check_registers(MilkymistTMU2State *s)
 355 {
 356     if (s->regs[R_BRIGHTNESS] > MAX_BRIGHTNESS) {
 357         error_report("milkymist_tmu2: max brightness is %d", MAX_BRIGHTNESS);
 358     }
 359
 360     if (s->regs[R_ALPHA] > MAX_ALPHA) {
 361         error_report("milkymist_tmu2: max alpha is %d", MAX_ALPHA);
 362     }
 363
 364     if (s->regs[R_VERTICESADDR] & 0x07) {
 365         error_report("milkymist_tmu2: vertex mesh address has to be 64-bit "
 366                 "aligned");
 367     }
 368
 369     if (s->regs[R_TEXFBUF] & 0x01) {
 370         error_report("milkymist_tmu2: texture buffer address has to be "
 371                 "16-bit aligned");
 372     }
 373 }
 374
 375 static void tmu2_write(void *opaque, hwaddr addr, uint64_t value,
 376                        unsigned size)
 377 {
 378     MilkymistTMU2State *s = opaque;
 379
 380     trace_milkymist_tmu2_memory_write(addr, value);
 381
 382     addr >>= 2;
 383     switch (addr) {
 384     case R_CTL:
 385         s->regs[addr] = value;
 386         if (value & CTL_START_BUSY) {
 387             tmu2_start(s);
 388         }
 389         break;
 390     case R_BRIGHTNESS:
 391     case R_HMESHLAST:
 392     case R_VMESHLAST:
 393     case R_CHROMAKEY:
 394     case R_VERTICESADDR:
 395     case R_TEXFBUF:
 396     case R_TEXHRES:
 397     case R_TEXVRES:
 398     case R_TEXHMASK:
 399     case R_TEXVMASK:
 400     case R_DSTFBUF:
 401     case R_DSTHRES:
 402     case R_DSTVRES:
 403     case R_DSTHOFFSET:
 404     case R_DSTVOFFSET:
 405     case R_DSTSQUAREW:
 406     case R_DSTSQUAREH:
 407     case R_ALPHA:
 408         s->regs[addr] = value;
 409         break;
 410
 411     default:
 412         error_report("milkymist_tmu2: write access to unknown register 0x"
 413                 TARGET_FMT_plx, addr << 2);
 414         break;
 415     }
 416
 417     tmu2_check_registers(s);
 418 }
 419
 420 static const MemoryRegionOps tmu2_mmio_ops = {
 421     .read = tmu2_read,
 422     .write = tmu2_write,
 423     .valid = {
 424         .min_access_size = 4,
 425         .max_access_size = 4,
 426     },
 427     .endianness = DEVICE_NATIVE_ENDIAN,
 428 };
 429
 430 static void milkymist_tmu2_reset(DeviceState *d)
 431 {
 432     MilkymistTMU2State *s = container_of(d, MilkymistTMU2State, busdev.qdev);
 433     int i;
 434
 435     for (i = 0; i < R_MAX; i++) {
 436         s->regs[i] = 0;
 437     }
 438 }
 439
 440 static int milkymist_tmu2_init(SysBusDevice *dev)
 441 {
 442     MilkymistTMU2State *s = FROM_SYSBUS(typeof(*s), dev);
 443
 444     if (tmu2_glx_init(s)) {
 445         return 1;
 446     }
 447
 448     sysbus_init_irq(dev, &s->irq);
 449
 450     memory_region_init_io(&s->regs_region, &tmu2_mmio_ops, s,
 451             "milkymist-tmu2", R_MAX * 4);
 452     sysbus_init_mmio(dev, &s->regs_region);
 453
 454     return 0;
 455 }
 456
 457 static const VMStateDescription vmstate_milkymist_tmu2 = {
 458     .name = "milkymist-tmu2",
 459     .version_id = 1,
 460     .minimum_version_id = 1,
 461     .minimum_version_id_old = 1,
 462     .fields      = (VMStateField[]) {
 463         VMSTATE_UINT32_ARRAY(regs, MilkymistTMU2State, R_MAX),
 464         VMSTATE_END_OF_LIST()
 465     }
 466 };
 467
 468 static void milkymist_tmu2_class_init(ObjectClass *klass, void *data)
 469 {
 470     DeviceClass *dc = DEVICE_CLASS(klass);
 471     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 472
 473     k->init = milkymist_tmu2_init;
 474     dc->reset = milkymist_tmu2_reset;
 475     dc->vmsd = &vmstate_milkymist_tmu2;
 476 }
 477
 478 static const TypeInfo milkymist_tmu2_info = {
 479     .name          = "milkymist-tmu2",
 480     .parent        = TYPE_SYS_BUS_DEVICE,
 481     .instance_size = sizeof(MilkymistTMU2State),
 482     .class_init    = milkymist_tmu2_class_init,
 483 };
 484
 485 static void milkymist_tmu2_register_types(void)
 486 {
 487     type_register_static(&milkymist_tmu2_info);
 488 }
 489
 490 type_init(milkymist_tmu2_register_types)