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