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/irq.h"
  29 #include "hw/sysbus.h"
  30 #include "migration/vmstate.h"
  31 #include "trace.h"
  32 #include "qapi/error.h"
  33 #include "qemu/error-report.h"
  34 #include "qemu/module.h"
  35 #include "qapi/error.h"
  36 #include "hw/display/milkymist_tmu2.h"
  37
  38 #include <X11/Xlib.h>
  39 #include <epoxy/gl.h>
  40 #include <epoxy/glx.h>
  41
  42 enum {
  43     R_CTL = 0,
  44     R_HMESHLAST,
  45     R_VMESHLAST,
  46     R_BRIGHTNESS,
  47     R_CHROMAKEY,
  48     R_VERTICESADDR,
  49     R_TEXFBUF,
  50     R_TEXHRES,
  51     R_TEXVRES,
  52     R_TEXHMASK,
  53     R_TEXVMASK,
  54     R_DSTFBUF,
  55     R_DSTHRES,
  56     R_DSTVRES,
  57     R_DSTHOFFSET,
  58     R_DSTVOFFSET,
  59     R_DSTSQUAREW,
  60     R_DSTSQUAREH,
  61     R_ALPHA,
  62     R_MAX
  63 };
  64
  65 enum {
  66     CTL_START_BUSY  = (1<<0),
  67     CTL_CHROMAKEY   = (1<<1),
  68 };
  69
  70 enum {
  71     MAX_BRIGHTNESS = 63,
  72     MAX_ALPHA      = 63,
  73 };
  74
  75 enum {
  76     MESH_MAXSIZE = 128,
  77 };
  78
  79 struct vertex {
  80     int x;
  81     int y;
  82 } QEMU_PACKED;
  83
  84 #define TYPE_MILKYMIST_TMU2 "milkymist-tmu2"
  85 #define MILKYMIST_TMU2(obj) \
  86     OBJECT_CHECK(MilkymistTMU2State, (obj), TYPE_MILKYMIST_TMU2)
  87
  88 struct MilkymistTMU2State {
  89     SysBusDevice parent_obj;
  90
  91     MemoryRegion regs_region;
  92     Chardev *chr;
  93     qemu_irq irq;
  94
  95     uint32_t regs[R_MAX];
  96
  97     Display *dpy;
  98     GLXFBConfig glx_fb_config;
  99     GLXContext glx_context;
 100 };
 101 typedef struct MilkymistTMU2State MilkymistTMU2State;
 102
 103 static const int glx_fbconfig_attr[] = {
 104     GLX_GREEN_SIZE, 5,
 105     GLX_GREEN_SIZE, 6,
 106     GLX_BLUE_SIZE, 5,
 107     None
 108 };
 109
 110 static int tmu2_glx_init(MilkymistTMU2State *s)
 111 {
 112     GLXFBConfig *configs;
 113     int nelements;
 114
 115     s->dpy = XOpenDisplay(NULL); /* FIXME: call XCloseDisplay() */
 116     if (s->dpy == NULL) {
 117         return 1;
 118     }
 119
 120     configs = glXChooseFBConfig(s->dpy, 0, glx_fbconfig_attr, &nelements);
 121     if (configs == NULL) {
 122         return 1;
 123     }
 124
 125     s->glx_fb_config = *configs;
 126     XFree(configs);
 127
 128     /* FIXME: call glXDestroyContext() */
 129     s->glx_context = glXCreateNewContext(s->dpy, s->glx_fb_config,
 130             GLX_RGBA_TYPE, NULL, 1);
 131     if (s->glx_context == NULL) {
 132         return 1;
 133     }
 134
 135     return 0;
 136 }
 137
 138 static void tmu2_gl_map(struct vertex *mesh, int texhres, int texvres,
 139         int hmeshlast, int vmeshlast, int ho, int vo, int sw, int sh)
 140 {
 141     int x, y;
 142     int x0, y0, x1, y1;
 143     int u0, v0, u1, v1, u2, v2, u3, v3;
 144     double xscale = 1.0 / ((double)(64 * texhres));
 145     double yscale = 1.0 / ((double)(64 * texvres));
 146
 147     glLoadIdentity();
 148     glTranslatef(ho, vo, 0);
 149     glEnable(GL_TEXTURE_2D);
 150     glBegin(GL_QUADS);
 151
 152     for (y = 0; y < vmeshlast; y++) {
 153         y0 = y * sh;
 154         y1 = y0 + sh;
 155         for (x = 0; x < hmeshlast; x++) {
 156             x0 = x * sw;
 157             x1 = x0 + sw;
 158
 159             u0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].x);
 160             v0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].y);
 161             u1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].x);
 162             v1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].y);
 163             u2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].x);
 164             v2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].y);
 165             u3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].x);
 166             v3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].y);
 167
 168             glTexCoord2d(((double)u0) * xscale, ((double)v0) * yscale);
 169             glVertex3i(x0, y0, 0);
 170             glTexCoord2d(((double)u1) * xscale, ((double)v1) * yscale);
 171             glVertex3i(x1, y0, 0);
 172             glTexCoord2d(((double)u2) * xscale, ((double)v2) * yscale);
 173             glVertex3i(x1, y1, 0);
 174             glTexCoord2d(((double)u3) * xscale, ((double)v3) * yscale);
 175             glVertex3i(x0, y1, 0);
 176         }
 177     }
 178
 179     glEnd();
 180 }
 181
 182 static void tmu2_start(MilkymistTMU2State *s)
 183 {
 184     int pbuffer_attrib[6] = {
 185         GLX_PBUFFER_WIDTH,
 186         0,
 187         GLX_PBUFFER_HEIGHT,
 188         0,
 189         GLX_PRESERVED_CONTENTS,
 190         True
 191     };
 192
 193     GLXPbuffer pbuffer;
 194     GLuint texture;
 195     void *fb;
 196     hwaddr fb_len;
 197     void *mesh;
 198     hwaddr mesh_len;
 199     float m;
 200
 201     trace_milkymist_tmu2_start();
 202
 203     /* Create and set up a suitable OpenGL context */
 204     pbuffer_attrib[1] = s->regs[R_DSTHRES];
 205     pbuffer_attrib[3] = s->regs[R_DSTVRES];
 206     pbuffer = glXCreatePbuffer(s->dpy, s->glx_fb_config, pbuffer_attrib);
 207     glXMakeContextCurrent(s->dpy, pbuffer, pbuffer, s->glx_context);
 208
 209     /* Fixup endianness. TODO: would it work on BE hosts? */
 210     glPixelStorei(GL_UNPACK_SWAP_BYTES, 1);
 211     glPixelStorei(GL_PACK_SWAP_BYTES, 1);
 212
 213     /* Row alignment */
 214     glPixelStorei(GL_UNPACK_ALIGNMENT, 2);
 215     glPixelStorei(GL_PACK_ALIGNMENT, 2);
 216
 217     /* Read the QEMU source framebuffer into an OpenGL texture */
 218     glGenTextures(1, &texture);
 219     glBindTexture(GL_TEXTURE_2D, texture);
 220     fb_len = 2ULL * s->regs[R_TEXHRES] * s->regs[R_TEXVRES];
 221     fb = cpu_physical_memory_map(s->regs[R_TEXFBUF], &fb_len, false);
 222     if (fb == NULL) {
 223         glDeleteTextures(1, &texture);
 224         glXMakeContextCurrent(s->dpy, None, None, NULL);
 225         glXDestroyPbuffer(s->dpy, pbuffer);
 226         return;
 227     }
 228     glTexImage2D(GL_TEXTURE_2D, 0, 3, s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 229             0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, fb);
 230     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 231
 232     /* Set up texturing options */
 233     /* WARNING:
 234      * Many cases of TMU2 masking are not supported by OpenGL.
 235      * We only implement the most common ones:
 236      *  - full bilinear filtering vs. nearest texel
 237      *  - texture clamping vs. texture wrapping
 238      */
 239     if ((s->regs[R_TEXHMASK] & 0x3f) > 0x20) {
 240         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 241         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 242     } else {
 243         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 244         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 245     }
 246     if ((s->regs[R_TEXHMASK] >> 6) & s->regs[R_TEXHRES]) {
 247         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
 248     } else {
 249         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 250     }
 251     if ((s->regs[R_TEXVMASK] >> 6) & s->regs[R_TEXVRES]) {
 252         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 253     } else {
 254         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 255     }
 256
 257     /* Translucency and decay */
 258     glEnable(GL_BLEND);
 259     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 260     m = (float)(s->regs[R_BRIGHTNESS] + 1) / 64.0f;
 261     glColor4f(m, m, m, (float)(s->regs[R_ALPHA] + 1) / 64.0f);
 262
 263     /* Read the QEMU dest. framebuffer into the OpenGL framebuffer */
 264     fb_len = 2ULL * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 265     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, false);
 266     if (fb == NULL) {
 267         glDeleteTextures(1, &texture);
 268         glXMakeContextCurrent(s->dpy, None, None, NULL);
 269         glXDestroyPbuffer(s->dpy, pbuffer);
 270         return;
 271     }
 272
 273     glDrawPixels(s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 274             GL_UNSIGNED_SHORT_5_6_5, fb);
 275     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 276     glViewport(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES]);
 277     glMatrixMode(GL_PROJECTION);
 278     glLoadIdentity();
 279     glOrtho(0.0, s->regs[R_DSTHRES], 0.0, s->regs[R_DSTVRES], -1.0, 1.0);
 280     glMatrixMode(GL_MODELVIEW);
 281
 282     /* Map the texture */
 283     mesh_len = MESH_MAXSIZE*MESH_MAXSIZE*sizeof(struct vertex);
 284     mesh = cpu_physical_memory_map(s->regs[R_VERTICESADDR], &mesh_len, false);
 285     if (mesh == NULL) {
 286         glDeleteTextures(1, &texture);
 287         glXMakeContextCurrent(s->dpy, None, None, NULL);
 288         glXDestroyPbuffer(s->dpy, pbuffer);
 289         return;
 290     }
 291
 292     tmu2_gl_map((struct vertex *)mesh,
 293         s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 294         s->regs[R_HMESHLAST], s->regs[R_VMESHLAST],
 295         s->regs[R_DSTHOFFSET], s->regs[R_DSTVOFFSET],
 296         s->regs[R_DSTSQUAREW], s->regs[R_DSTSQUAREH]);
 297     cpu_physical_memory_unmap(mesh, mesh_len, 0, mesh_len);
 298
 299     /* Write back the OpenGL framebuffer to the QEMU framebuffer */
 300     fb_len = 2ULL * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 301     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, true);
 302     if (fb == NULL) {
 303         glDeleteTextures(1, &texture);
 304         glXMakeContextCurrent(s->dpy, None, None, NULL);
 305         glXDestroyPbuffer(s->dpy, pbuffer);
 306         return;
 307     }
 308
 309     glReadPixels(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 310             GL_UNSIGNED_SHORT_5_6_5, fb);
 311     cpu_physical_memory_unmap(fb, fb_len, 1, fb_len);
 312
 313     /* Free OpenGL allocs */
 314     glDeleteTextures(1, &texture);
 315     glXMakeContextCurrent(s->dpy, None, None, NULL);
 316     glXDestroyPbuffer(s->dpy, pbuffer);
 317
 318     s->regs[R_CTL] &= ~CTL_START_BUSY;
 319
 320     trace_milkymist_tmu2_pulse_irq();
 321     qemu_irq_pulse(s->irq);
 322 }
 323
 324 static uint64_t tmu2_read(void *opaque, hwaddr addr,
 325                           unsigned size)
 326 {
 327     MilkymistTMU2State *s = opaque;
 328     uint32_t r = 0;
 329
 330     addr >>= 2;
 331     switch (addr) {
 332     case R_CTL:
 333     case R_HMESHLAST:
 334     case R_VMESHLAST:
 335     case R_BRIGHTNESS:
 336     case R_CHROMAKEY:
 337     case R_VERTICESADDR:
 338     case R_TEXFBUF:
 339     case R_TEXHRES:
 340     case R_TEXVRES:
 341     case R_TEXHMASK:
 342     case R_TEXVMASK:
 343     case R_DSTFBUF:
 344     case R_DSTHRES:
 345     case R_DSTVRES:
 346     case R_DSTHOFFSET:
 347     case R_DSTVOFFSET:
 348     case R_DSTSQUAREW:
 349     case R_DSTSQUAREH:
 350     case R_ALPHA:
 351         r = s->regs[addr];
 352         break;
 353
 354     default:
 355         error_report("milkymist_tmu2: read access to unknown register 0x"
 356                 TARGET_FMT_plx, addr << 2);
 357         break;
 358     }
 359
 360     trace_milkymist_tmu2_memory_read(addr << 2, r);
 361
 362     return r;
 363 }
 364
 365 static void tmu2_check_registers(MilkymistTMU2State *s)
 366 {
 367     if (s->regs[R_BRIGHTNESS] > MAX_BRIGHTNESS) {
 368         error_report("milkymist_tmu2: max brightness is %d", MAX_BRIGHTNESS);
 369     }
 370
 371     if (s->regs[R_ALPHA] > MAX_ALPHA) {
 372         error_report("milkymist_tmu2: max alpha is %d", MAX_ALPHA);
 373     }
 374
 375     if (s->regs[R_VERTICESADDR] & 0x07) {
 376         error_report("milkymist_tmu2: vertex mesh address has to be 64-bit "
 377                 "aligned");
 378     }
 379
 380     if (s->regs[R_TEXFBUF] & 0x01) {
 381         error_report("milkymist_tmu2: texture buffer address has to be "
 382                 "16-bit aligned");
 383     }
 384 }
 385
 386 static void tmu2_write(void *opaque, hwaddr addr, uint64_t value,
 387                        unsigned size)
 388 {
 389     MilkymistTMU2State *s = opaque;
 390
 391     trace_milkymist_tmu2_memory_write(addr, value);
 392
 393     addr >>= 2;
 394     switch (addr) {
 395     case R_CTL:
 396         s->regs[addr] = value;
 397         if (value & CTL_START_BUSY) {
 398             tmu2_start(s);
 399         }
 400         break;
 401     case R_BRIGHTNESS:
 402     case R_HMESHLAST:
 403     case R_VMESHLAST:
 404     case R_CHROMAKEY:
 405     case R_VERTICESADDR:
 406     case R_TEXFBUF:
 407     case R_TEXHRES:
 408     case R_TEXVRES:
 409     case R_TEXHMASK:
 410     case R_TEXVMASK:
 411     case R_DSTFBUF:
 412     case R_DSTHRES:
 413     case R_DSTVRES:
 414     case R_DSTHOFFSET:
 415     case R_DSTVOFFSET:
 416     case R_DSTSQUAREW:
 417     case R_DSTSQUAREH:
 418     case R_ALPHA:
 419         s->regs[addr] = value;
 420         break;
 421
 422     default:
 423         error_report("milkymist_tmu2: write access to unknown register 0x"
 424                 TARGET_FMT_plx, addr << 2);
 425         break;
 426     }
 427
 428     tmu2_check_registers(s);
 429 }
 430
 431 static const MemoryRegionOps tmu2_mmio_ops = {
 432     .read = tmu2_read,
 433     .write = tmu2_write,
 434     .valid = {
 435         .min_access_size = 4,
 436         .max_access_size = 4,
 437     },
 438     .endianness = DEVICE_NATIVE_ENDIAN,
 439 };
 440
 441 static void milkymist_tmu2_reset(DeviceState *d)
 442 {
 443     MilkymistTMU2State *s = MILKYMIST_TMU2(d);
 444     int i;
 445
 446     for (i = 0; i < R_MAX; i++) {
 447         s->regs[i] = 0;
 448     }
 449 }
 450
 451 static void milkymist_tmu2_init(Object *obj)
 452 {
 453     MilkymistTMU2State *s = MILKYMIST_TMU2(obj);
 454     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
 455
 456     sysbus_init_irq(dev, &s->irq);
 457
 458     memory_region_init_io(&s->regs_region, obj, &tmu2_mmio_ops, s,
 459             "milkymist-tmu2", R_MAX * 4);
 460     sysbus_init_mmio(dev, &s->regs_region);
 461 }
 462
 463 static void milkymist_tmu2_realize(DeviceState *dev, Error **errp)
 464 {
 465     MilkymistTMU2State *s = MILKYMIST_TMU2(dev);
 466
 467     if (tmu2_glx_init(s)) {
 468         error_setg(errp, "tmu2_glx_init failed");
 469     }
 470 }
 471
 472 static const VMStateDescription vmstate_milkymist_tmu2 = {
 473     .name = "milkymist-tmu2",
 474     .version_id = 1,
 475     .minimum_version_id = 1,
 476     .fields = (VMStateField[]) {
 477         VMSTATE_UINT32_ARRAY(regs, MilkymistTMU2State, R_MAX),
 478         VMSTATE_END_OF_LIST()
 479     }
 480 };
 481
 482 static void milkymist_tmu2_class_init(ObjectClass *klass, void *data)
 483 {
 484     DeviceClass *dc = DEVICE_CLASS(klass);
 485
 486     dc->realize = milkymist_tmu2_realize;
 487     dc->reset = milkymist_tmu2_reset;
 488     dc->vmsd = &vmstate_milkymist_tmu2;
 489 }
 490
 491 static const TypeInfo milkymist_tmu2_info = {
 492     .name          = TYPE_MILKYMIST_TMU2,
 493     .parent        = TYPE_SYS_BUS_DEVICE,
 494     .instance_size = sizeof(MilkymistTMU2State),
 495     .instance_init = milkymist_tmu2_init,
 496     .class_init    = milkymist_tmu2_class_init,
 497 };
 498
 499 static void milkymist_tmu2_register_types(void)
 500 {
 501     type_register_static(&milkymist_tmu2_info);
 502 }
 503
 504 type_init(milkymist_tmu2_register_types)
 505
 506 DeviceState *milkymist_tmu2_create(hwaddr base, qemu_irq irq)
 507 {
 508     DeviceState *dev;
 509     Display *d;
 510     GLXFBConfig *configs;
 511     int nelements;
 512     int ver_major, ver_minor;
 513
 514     /* check that GLX will work */
 515     d = XOpenDisplay(NULL);
 516     if (d == NULL) {
 517         return NULL;
 518     }
 519
 520     if (!glXQueryVersion(d, &ver_major, &ver_minor)) {
 521         /*
 522          * Yeah, sometimes getting the GLX version can fail.
 523          * Isn't X beautiful?
 524          */
 525         XCloseDisplay(d);
 526         return NULL;
 527     }
 528
 529     if ((ver_major < 1) || ((ver_major == 1) && (ver_minor < 3))) {
 530         printf("Your GLX version is %d.%d,"
 531           "but TMU emulation needs at least 1.3. TMU disabled.\n",
 532           ver_major, ver_minor);
 533         XCloseDisplay(d);
 534         return NULL;
 535     }
 536
 537     configs = glXChooseFBConfig(d, 0, glx_fbconfig_attr, &nelements);
 538     if (configs == NULL) {
 539         XCloseDisplay(d);
 540         return NULL;
 541     }
 542
 543     XFree(configs);
 544     XCloseDisplay(d);
 545
 546     dev = qdev_new(TYPE_MILKYMIST_TMU2);
 547     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
 548     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
 549     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);
 550
 551     return dev;
 552 }