hw/display/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://milkymist.walle.cc/socdoc/tmu2.pdf
  24  *
  25  */
  26
  27 #include "qemu/osdep.h"
  28 #include "hw/hw.h"
  29 #include "hw/sysbus.h"
  30 #include "trace.h"
  31 #include "qapi/error.h"
  32 #include "qemu/error-report.h"
  33 #include "qemu/module.h"
  34 #include "qapi/error.h"
  35 #include "hw/display/milkymist_tmu2.h"
  36
  37 #include <X11/Xlib.h>
  38 #include <epoxy/gl.h>
  39 #include <epoxy/glx.h>
  40
  41 enum {
  42     R_CTL = 0,
  43     R_HMESHLAST,
  44     R_VMESHLAST,
  45     R_BRIGHTNESS,
  46     R_CHROMAKEY,
  47     R_VERTICESADDR,
  48     R_TEXFBUF,
  49     R_TEXHRES,
  50     R_TEXVRES,
  51     R_TEXHMASK,
  52     R_TEXVMASK,
  53     R_DSTFBUF,
  54     R_DSTHRES,
  55     R_DSTVRES,
  56     R_DSTHOFFSET,
  57     R_DSTVOFFSET,
  58     R_DSTSQUAREW,
  59     R_DSTSQUAREH,
  60     R_ALPHA,
  61     R_MAX
  62 };
  63
  64 enum {
  65     CTL_START_BUSY  = (1<<0),
  66     CTL_CHROMAKEY   = (1<<1),
  67 };
  68
  69 enum {
  70     MAX_BRIGHTNESS = 63,
  71     MAX_ALPHA      = 63,
  72 };
  73
  74 enum {
  75     MESH_MAXSIZE = 128,
  76 };
  77
  78 struct vertex {
  79     int x;
  80     int y;
  81 } QEMU_PACKED;
  82
  83 #define TYPE_MILKYMIST_TMU2 "milkymist-tmu2"
  84 #define MILKYMIST_TMU2(obj) \
  85     OBJECT_CHECK(MilkymistTMU2State, (obj), TYPE_MILKYMIST_TMU2)
  86
  87 struct MilkymistTMU2State {
  88     SysBusDevice parent_obj;
  89
  90     MemoryRegion regs_region;
  91     Chardev *chr;
  92     qemu_irq irq;
  93
  94     uint32_t regs[R_MAX];
  95
  96     Display *dpy;
  97     GLXFBConfig glx_fb_config;
  98     GLXContext glx_context;
  99 };
 100 typedef struct MilkymistTMU2State MilkymistTMU2State;
 101
 102 static const int glx_fbconfig_attr[] = {
 103     GLX_GREEN_SIZE, 5,
 104     GLX_GREEN_SIZE, 6,
 105     GLX_BLUE_SIZE, 5,
 106     None
 107 };
 108
 109 static int tmu2_glx_init(MilkymistTMU2State *s)
 110 {
 111     GLXFBConfig *configs;
 112     int nelements;
 113
 114     s->dpy = XOpenDisplay(NULL); /* FIXME: call XCloseDisplay() */
 115     if (s->dpy == NULL) {
 116         return 1;
 117     }
 118
 119     configs = glXChooseFBConfig(s->dpy, 0, glx_fbconfig_attr, &nelements);
 120     if (configs == NULL) {
 121         return 1;
 122     }
 123
 124     s->glx_fb_config = *configs;
 125     XFree(configs);
 126
 127     /* FIXME: call glXDestroyContext() */
 128     s->glx_context = glXCreateNewContext(s->dpy, s->glx_fb_config,
 129             GLX_RGBA_TYPE, NULL, 1);
 130     if (s->glx_context == NULL) {
 131         return 1;
 132     }
 133
 134     return 0;
 135 }
 136
 137 static void tmu2_gl_map(struct vertex *mesh, int texhres, int texvres,
 138         int hmeshlast, int vmeshlast, int ho, int vo, int sw, int sh)
 139 {
 140     int x, y;
 141     int x0, y0, x1, y1;
 142     int u0, v0, u1, v1, u2, v2, u3, v3;
 143     double xscale = 1.0 / ((double)(64 * texhres));
 144     double yscale = 1.0 / ((double)(64 * texvres));
 145
 146     glLoadIdentity();
 147     glTranslatef(ho, vo, 0);
 148     glEnable(GL_TEXTURE_2D);
 149     glBegin(GL_QUADS);
 150
 151     for (y = 0; y < vmeshlast; y++) {
 152         y0 = y * sh;
 153         y1 = y0 + sh;
 154         for (x = 0; x < hmeshlast; x++) {
 155             x0 = x * sw;
 156             x1 = x0 + sw;
 157
 158             u0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].x);
 159             v0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].y);
 160             u1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].x);
 161             v1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].y);
 162             u2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].x);
 163             v2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].y);
 164             u3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].x);
 165             v3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].y);
 166
 167             glTexCoord2d(((double)u0) * xscale, ((double)v0) * yscale);
 168             glVertex3i(x0, y0, 0);
 169             glTexCoord2d(((double)u1) * xscale, ((double)v1) * yscale);
 170             glVertex3i(x1, y0, 0);
 171             glTexCoord2d(((double)u2) * xscale, ((double)v2) * yscale);
 172             glVertex3i(x1, y1, 0);
 173             glTexCoord2d(((double)u3) * xscale, ((double)v3) * yscale);
 174             glVertex3i(x0, y1, 0);
 175         }
 176     }
 177
 178     glEnd();
 179 }
 180
 181 static void tmu2_start(MilkymistTMU2State *s)
 182 {
 183     int pbuffer_attrib[6] = {
 184         GLX_PBUFFER_WIDTH,
 185         0,
 186         GLX_PBUFFER_HEIGHT,
 187         0,
 188         GLX_PRESERVED_CONTENTS,
 189         True
 190     };
 191
 192     GLXPbuffer pbuffer;
 193     GLuint texture;
 194     void *fb;
 195     hwaddr fb_len;
 196     void *mesh;
 197     hwaddr mesh_len;
 198     float m;
 199
 200     trace_milkymist_tmu2_start();
 201
 202     /* Create and set up a suitable OpenGL context */
 203     pbuffer_attrib[1] = s->regs[R_DSTHRES];
 204     pbuffer_attrib[3] = s->regs[R_DSTVRES];
 205     pbuffer = glXCreatePbuffer(s->dpy, s->glx_fb_config, pbuffer_attrib);
 206     glXMakeContextCurrent(s->dpy, pbuffer, pbuffer, s->glx_context);
 207
 208     /* Fixup endianness. TODO: would it work on BE hosts? */
 209     glPixelStorei(GL_UNPACK_SWAP_BYTES, 1);
 210     glPixelStorei(GL_PACK_SWAP_BYTES, 1);
 211
 212     /* Row alignment */
 213     glPixelStorei(GL_UNPACK_ALIGNMENT, 2);
 214     glPixelStorei(GL_PACK_ALIGNMENT, 2);
 215
 216     /* Read the QEMU source framebuffer into an OpenGL texture */
 217     glGenTextures(1, &texture);
 218     glBindTexture(GL_TEXTURE_2D, texture);
 219     fb_len = 2ULL * s->regs[R_TEXHRES] * s->regs[R_TEXVRES];
 220     fb = cpu_physical_memory_map(s->regs[R_TEXFBUF], &fb_len, 0);
 221     if (fb == NULL) {
 222         glDeleteTextures(1, &texture);
 223         glXMakeContextCurrent(s->dpy, None, None, NULL);
 224         glXDestroyPbuffer(s->dpy, pbuffer);
 225         return;
 226     }
 227     glTexImage2D(GL_TEXTURE_2D, 0, 3, s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 228             0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, fb);
 229     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 230
 231     /* Set up texturing options */
 232     /* WARNING:
 233      * Many cases of TMU2 masking are not supported by OpenGL.
 234      * We only implement the most common ones:
 235      *  - full bilinear filtering vs. nearest texel
 236      *  - texture clamping vs. texture wrapping
 237      */
 238     if ((s->regs[R_TEXHMASK] & 0x3f) > 0x20) {
 239         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 240         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 241     } else {
 242         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 243         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 244     }
 245     if ((s->regs[R_TEXHMASK] >> 6) & s->regs[R_TEXHRES]) {
 246         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
 247     } else {
 248         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 249     }
 250     if ((s->regs[R_TEXVMASK] >> 6) & s->regs[R_TEXVRES]) {
 251         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 252     } else {
 253         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 254     }
 255
 256     /* Translucency and decay */
 257     glEnable(GL_BLEND);
 258     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 259     m = (float)(s->regs[R_BRIGHTNESS] + 1) / 64.0f;
 260     glColor4f(m, m, m, (float)(s->regs[R_ALPHA] + 1) / 64.0f);
 261
 262     /* Read the QEMU dest. framebuffer into the OpenGL framebuffer */
 263     fb_len = 2ULL * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 264     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 0);
 265     if (fb == NULL) {
 266         glDeleteTextures(1, &texture);
 267         glXMakeContextCurrent(s->dpy, None, None, NULL);
 268         glXDestroyPbuffer(s->dpy, pbuffer);
 269         return;
 270     }
 271
 272     glDrawPixels(s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 273             GL_UNSIGNED_SHORT_5_6_5, fb);
 274     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 275     glViewport(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES]);
 276     glMatrixMode(GL_PROJECTION);
 277     glLoadIdentity();
 278     glOrtho(0.0, s->regs[R_DSTHRES], 0.0, s->regs[R_DSTVRES], -1.0, 1.0);
 279     glMatrixMode(GL_MODELVIEW);
 280
 281     /* Map the texture */
 282     mesh_len = MESH_MAXSIZE*MESH_MAXSIZE*sizeof(struct vertex);
 283     mesh = cpu_physical_memory_map(s->regs[R_VERTICESADDR], &mesh_len, 0);
 284     if (mesh == NULL) {
 285         glDeleteTextures(1, &texture);
 286         glXMakeContextCurrent(s->dpy, None, None, NULL);
 287         glXDestroyPbuffer(s->dpy, pbuffer);
 288         return;
 289     }
 290
 291     tmu2_gl_map((struct vertex *)mesh,
 292         s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 293         s->regs[R_HMESHLAST], s->regs[R_VMESHLAST],
 294         s->regs[R_DSTHOFFSET], s->regs[R_DSTVOFFSET],
 295         s->regs[R_DSTSQUAREW], s->regs[R_DSTSQUAREH]);
 296     cpu_physical_memory_unmap(mesh, mesh_len, 0, mesh_len);
 297
 298     /* Write back the OpenGL framebuffer to the QEMU framebuffer */
 299     fb_len = 2ULL * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 300     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 1);
 301     if (fb == NULL) {
 302         glDeleteTextures(1, &texture);
 303         glXMakeContextCurrent(s->dpy, None, None, NULL);
 304         glXDestroyPbuffer(s->dpy, pbuffer);
 305         return;
 306     }
 307
 308     glReadPixels(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 309             GL_UNSIGNED_SHORT_5_6_5, fb);
 310     cpu_physical_memory_unmap(fb, fb_len, 1, fb_len);
 311
 312     /* Free OpenGL allocs */
 313     glDeleteTextures(1, &texture);
 314     glXMakeContextCurrent(s->dpy, None, None, NULL);
 315     glXDestroyPbuffer(s->dpy, pbuffer);
 316
 317     s->regs[R_CTL] &= ~CTL_START_BUSY;
 318
 319     trace_milkymist_tmu2_pulse_irq();
 320     qemu_irq_pulse(s->irq);
 321 }
 322
 323 static uint64_t tmu2_read(void *opaque, hwaddr addr,
 324                           unsigned size)
 325 {
 326     MilkymistTMU2State *s = opaque;
 327     uint32_t r = 0;
 328
 329     addr >>= 2;
 330     switch (addr) {
 331     case R_CTL:
 332     case R_HMESHLAST:
 333     case R_VMESHLAST:
 334     case R_BRIGHTNESS:
 335     case R_CHROMAKEY:
 336     case R_VERTICESADDR:
 337     case R_TEXFBUF:
 338     case R_TEXHRES:
 339     case R_TEXVRES:
 340     case R_TEXHMASK:
 341     case R_TEXVMASK:
 342     case R_DSTFBUF:
 343     case R_DSTHRES:
 344     case R_DSTVRES:
 345     case R_DSTHOFFSET:
 346     case R_DSTVOFFSET:
 347     case R_DSTSQUAREW:
 348     case R_DSTSQUAREH:
 349     case R_ALPHA:
 350         r = s->regs[addr];
 351         break;
 352
 353     default:
 354         error_report("milkymist_tmu2: read access to unknown register 0x"
 355                 TARGET_FMT_plx, addr << 2);
 356         break;
 357     }
 358
 359     trace_milkymist_tmu2_memory_read(addr << 2, r);
 360
 361     return r;
 362 }
 363
 364 static void tmu2_check_registers(MilkymistTMU2State *s)
 365 {
 366     if (s->regs[R_BRIGHTNESS] > MAX_BRIGHTNESS) {
 367         error_report("milkymist_tmu2: max brightness is %d", MAX_BRIGHTNESS);
 368     }
 369
 370     if (s->regs[R_ALPHA] > MAX_ALPHA) {
 371         error_report("milkymist_tmu2: max alpha is %d", MAX_ALPHA);
 372     }
 373
 374     if (s->regs[R_VERTICESADDR] & 0x07) {
 375         error_report("milkymist_tmu2: vertex mesh address has to be 64-bit "
 376                 "aligned");
 377     }
 378
 379     if (s->regs[R_TEXFBUF] & 0x01) {
 380         error_report("milkymist_tmu2: texture buffer address has to be "
 381                 "16-bit aligned");
 382     }
 383 }
 384
 385 static void tmu2_write(void *opaque, hwaddr addr, uint64_t value,
 386                        unsigned size)
 387 {
 388     MilkymistTMU2State *s = opaque;
 389
 390     trace_milkymist_tmu2_memory_write(addr, value);
 391
 392     addr >>= 2;
 393     switch (addr) {
 394     case R_CTL:
 395         s->regs[addr] = value;
 396         if (value & CTL_START_BUSY) {
 397             tmu2_start(s);
 398         }
 399         break;
 400     case R_BRIGHTNESS:
 401     case R_HMESHLAST:
 402     case R_VMESHLAST:
 403     case R_CHROMAKEY:
 404     case R_VERTICESADDR:
 405     case R_TEXFBUF:
 406     case R_TEXHRES:
 407     case R_TEXVRES:
 408     case R_TEXHMASK:
 409     case R_TEXVMASK:
 410     case R_DSTFBUF:
 411     case R_DSTHRES:
 412     case R_DSTVRES:
 413     case R_DSTHOFFSET:
 414     case R_DSTVOFFSET:
 415     case R_DSTSQUAREW:
 416     case R_DSTSQUAREH:
 417     case R_ALPHA:
 418         s->regs[addr] = value;
 419         break;
 420
 421     default:
 422         error_report("milkymist_tmu2: write access to unknown register 0x"
 423                 TARGET_FMT_plx, addr << 2);
 424         break;
 425     }
 426
 427     tmu2_check_registers(s);
 428 }
 429
 430 static const MemoryRegionOps tmu2_mmio_ops = {
 431     .read = tmu2_read,
 432     .write = tmu2_write,
 433     .valid = {
 434         .min_access_size = 4,
 435         .max_access_size = 4,
 436     },
 437     .endianness = DEVICE_NATIVE_ENDIAN,
 438 };
 439
 440 static void milkymist_tmu2_reset(DeviceState *d)
 441 {
 442     MilkymistTMU2State *s = MILKYMIST_TMU2(d);
 443     int i;
 444
 445     for (i = 0; i < R_MAX; i++) {
 446         s->regs[i] = 0;
 447     }
 448 }
 449
 450 static void milkymist_tmu2_init(Object *obj)
 451 {
 452     MilkymistTMU2State *s = MILKYMIST_TMU2(obj);
 453     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 454
 455     sysbus_init_irq(dev, &s->irq);
 456
 457     memory_region_init_io(&s->regs_region, obj, &tmu2_mmio_ops, s,
 458             "milkymist-tmu2", R_MAX * 4);
 459     sysbus_init_mmio(dev, &s->regs_region);
 460 }
 461
 462 static void milkymist_tmu2_realize(DeviceState *dev, Error **errp)
 463 {
 464     MilkymistTMU2State *s = MILKYMIST_TMU2(dev);
 465
 466     if (tmu2_glx_init(s)) {
 467         error_setg(errp, "tmu2_glx_init failed");
 468     }
 469 }
 470
 471 static const VMStateDescription vmstate_milkymist_tmu2 = {
 472     .name = "milkymist-tmu2",
 473     .version_id = 1,
 474     .minimum_version_id = 1,
 475     .fields = (VMStateField[]) {
 476         VMSTATE_UINT32_ARRAY(regs, MilkymistTMU2State, R_MAX),
 477         VMSTATE_END_OF_LIST()
 478     }
 479 };
 480
 481 static void milkymist_tmu2_class_init(ObjectClass *klass, void *data)
 482 {
 483     DeviceClass *dc = DEVICE_CLASS(klass);
 484
 485     dc->realize = milkymist_tmu2_realize;
 486     dc->reset = milkymist_tmu2_reset;
 487     dc->vmsd = &vmstate_milkymist_tmu2;
 488 }
 489
 490 static const TypeInfo milkymist_tmu2_info = {
 491     .name          = TYPE_MILKYMIST_TMU2,
 492     .parent        = TYPE_SYS_BUS_DEVICE,
 493     .instance_size = sizeof(MilkymistTMU2State),
 494     .instance_init = milkymist_tmu2_init,
 495     .class_init    = milkymist_tmu2_class_init,
 496 };
 497
 498 static void milkymist_tmu2_register_types(void)
 499 {
 500     type_register_static(&milkymist_tmu2_info);
 501 }
 502
 503 type_init(milkymist_tmu2_register_types)
 504
 505 DeviceState *milkymist_tmu2_create(hwaddr base, qemu_irq irq)
 506 {
 507     DeviceState *dev;
 508     Display *d;
 509     GLXFBConfig *configs;
 510     int nelements;
 511     int ver_major, ver_minor;
 512
 513     /* check that GLX will work */
 514     d = XOpenDisplay(NULL);
 515     if (d == NULL) {
 516         return NULL;
 517     }
 518
 519     if (!glXQueryVersion(d, &ver_major, &ver_minor)) {
 520         /*
 521          * Yeah, sometimes getting the GLX version can fail.
 522          * Isn't X beautiful?
 523          */
 524         XCloseDisplay(d);
 525         return NULL;
 526     }
 527
 528     if ((ver_major < 1) || ((ver_major == 1) && (ver_minor < 3))) {
 529         printf("Your GLX version is %d.%d,"
 530           "but TMU emulation needs at least 1.3. TMU disabled.\n",
 531           ver_major, ver_minor);
 532         XCloseDisplay(d);
 533         return NULL;
 534     }
 535
 536     configs = glXChooseFBConfig(d, 0, glx_fbconfig_attr, &nelements);
 537     if (configs == NULL) {
 538         XCloseDisplay(d);
 539         return NULL;
 540     }
 541
 542     XFree(configs);
 543     XCloseDisplay(d);
 544
 545     dev = qdev_create(NULL, TYPE_MILKYMIST_TMU2);
 546     qdev_init_nofail(dev);
 547     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
 548     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);
 549
 550     return dev;
 551 }