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.h"
  28 #include "sysbus.h"
  29 #include "trace.h"
  30 #include "qemu-error.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 } __attribute__((packed));
  77
  78 struct MilkymistTMU2State {
  79     SysBusDevice busdev;
  80     CharDriverState *chr;
  81     qemu_irq irq;
  82
  83     uint32_t regs[R_MAX];
  84
  85     Display *dpy;
  86     GLXFBConfig glx_fb_config;
  87     GLXContext glx_context;
  88 };
  89 typedef struct MilkymistTMU2State MilkymistTMU2State;
  90
  91 static const int glx_fbconfig_attr[] = {
  92     GLX_GREEN_SIZE, 5,
  93     GLX_GREEN_SIZE, 6,
  94     GLX_BLUE_SIZE, 5,
  95     None
  96 };
  97
  98 static int tmu2_glx_init(MilkymistTMU2State *s)
  99 {
 100     GLXFBConfig *configs;
 101     int nelements;
 102
 103     s->dpy = XOpenDisplay(NULL); /* FIXME: call XCloseDisplay() */
 104     if (s->dpy == NULL) {
 105         return 1;
 106     }
 107
 108     configs = glXChooseFBConfig(s->dpy, 0, glx_fbconfig_attr, &nelements);
 109     if (configs == NULL) {
 110         return 1;
 111     }
 112
 113     s->glx_fb_config = *configs;
 114     XFree(configs);
 115
 116     /* FIXME: call glXDestroyContext() */
 117     s->glx_context = glXCreateNewContext(s->dpy, s->glx_fb_config,
 118             GLX_RGBA_TYPE, NULL, 1);
 119     if (s->glx_context == NULL) {
 120         return 1;
 121     }
 122
 123     return 0;
 124 }
 125
 126 static void tmu2_gl_map(struct vertex *mesh, int texhres, int texvres,
 127         int hmeshlast, int vmeshlast, int ho, int vo, int sw, int sh)
 128 {
 129     int x, y;
 130     int x0, y0, x1, y1;
 131     int u0, v0, u1, v1, u2, v2, u3, v3;
 132     double xscale = 1.0 / ((double)(64 * texhres));
 133     double yscale = 1.0 / ((double)(64 * texvres));
 134
 135     glLoadIdentity();
 136     glTranslatef(ho, vo, 0);
 137     glEnable(GL_TEXTURE_2D);
 138     glBegin(GL_QUADS);
 139
 140     for (y = 0; y < vmeshlast; y++) {
 141         y0 = y * sh;
 142         y1 = y0 + sh;
 143         for (x = 0; x < hmeshlast; x++) {
 144             x0 = x * sw;
 145             x1 = x0 + sw;
 146
 147             u0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].x);
 148             v0 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x].y);
 149             u1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].x);
 150             v1 = be32_to_cpu(mesh[MESH_MAXSIZE * y + x + 1].y);
 151             u2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].x);
 152             v2 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x + 1].y);
 153             u3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].x);
 154             v3 = be32_to_cpu(mesh[MESH_MAXSIZE * (y + 1) + x].y);
 155
 156             glTexCoord2d(((double)u0) * xscale, ((double)v0) * yscale);
 157             glVertex3i(x0, y0, 0);
 158             glTexCoord2d(((double)u1) * xscale, ((double)v1) * yscale);
 159             glVertex3i(x1, y0, 0);
 160             glTexCoord2d(((double)u2) * xscale, ((double)v2) * yscale);
 161             glVertex3i(x1, y1, 0);
 162             glTexCoord2d(((double)u3) * xscale, ((double)v3) * yscale);
 163             glVertex3i(x0, y1, 0);
 164         }
 165     }
 166
 167     glEnd();
 168 }
 169
 170 static void tmu2_start(MilkymistTMU2State *s)
 171 {
 172     int pbuffer_attrib[6] = {
 173         GLX_PBUFFER_WIDTH,
 174         0,
 175         GLX_PBUFFER_HEIGHT,
 176         0,
 177         GLX_PRESERVED_CONTENTS,
 178         True
 179     };
 180
 181     GLXPbuffer pbuffer;
 182     GLuint texture;
 183     void *fb;
 184     target_phys_addr_t fb_len;
 185     void *mesh;
 186     target_phys_addr_t mesh_len;
 187     float m;
 188
 189     trace_milkymist_tmu2_start();
 190
 191     /* Create and set up a suitable OpenGL context */
 192     pbuffer_attrib[1] = s->regs[R_DSTHRES];
 193     pbuffer_attrib[3] = s->regs[R_DSTVRES];
 194     pbuffer = glXCreatePbuffer(s->dpy, s->glx_fb_config, pbuffer_attrib);
 195     glXMakeContextCurrent(s->dpy, pbuffer, pbuffer, s->glx_context);
 196
 197     /* Fixup endianness. TODO: would it work on BE hosts? */
 198     glPixelStorei(GL_UNPACK_SWAP_BYTES, 1);
 199     glPixelStorei(GL_PACK_SWAP_BYTES, 1);
 200
 201     /* Row alignment */
 202     glPixelStorei(GL_UNPACK_ALIGNMENT, 2);
 203     glPixelStorei(GL_PACK_ALIGNMENT, 2);
 204
 205     /* Read the QEMU source framebuffer into an OpenGL texture */
 206     glGenTextures(1, &texture);
 207     glBindTexture(GL_TEXTURE_2D, texture);
 208     fb_len = 2*s->regs[R_TEXHRES]*s->regs[R_TEXVRES];
 209     fb = cpu_physical_memory_map(s->regs[R_TEXFBUF], &fb_len, 0);
 210     if (fb == NULL) {
 211         glDeleteTextures(1, &texture);
 212         glXMakeContextCurrent(s->dpy, None, None, NULL);
 213         glXDestroyPbuffer(s->dpy, pbuffer);
 214         return;
 215     }
 216     glTexImage2D(GL_TEXTURE_2D, 0, 3, s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 217             0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, fb);
 218     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 219
 220     /* Set up texturing options */
 221     /* WARNING:
 222      * Many cases of TMU2 masking are not supported by OpenGL.
 223      * We only implement the most common ones:
 224      *  - full bilinear filtering vs. nearest texel
 225      *  - texture clamping vs. texture wrapping
 226      */
 227     if ((s->regs[R_TEXHMASK] & 0x3f) > 0x20) {
 228         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 229         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 230     } else {
 231         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 232         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 233     }
 234     if ((s->regs[R_TEXHMASK] >> 6) & s->regs[R_TEXHRES]) {
 235         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
 236     } else {
 237         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 238     }
 239     if ((s->regs[R_TEXVMASK] >> 6) & s->regs[R_TEXVRES]) {
 240         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 241     } else {
 242         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 243     }
 244
 245     /* Translucency and decay */
 246     glEnable(GL_BLEND);
 247     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 248     m = (float)(s->regs[R_BRIGHTNESS] + 1) / 64.0f;
 249     glColor4f(m, m, m, (float)(s->regs[R_ALPHA] + 1) / 64.0f);
 250
 251     /* Read the QEMU dest. framebuffer into the OpenGL framebuffer */
 252     fb_len = 2 * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 253     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 0);
 254     if (fb == NULL) {
 255         glDeleteTextures(1, &texture);
 256         glXMakeContextCurrent(s->dpy, None, None, NULL);
 257         glXDestroyPbuffer(s->dpy, pbuffer);
 258         return;
 259     }
 260
 261     glDrawPixels(s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 262             GL_UNSIGNED_SHORT_5_6_5, fb);
 263     cpu_physical_memory_unmap(fb, fb_len, 0, fb_len);
 264     glViewport(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES]);
 265     glMatrixMode(GL_PROJECTION);
 266     glLoadIdentity();
 267     glOrtho(0.0, s->regs[R_DSTHRES], 0.0, s->regs[R_DSTVRES], -1.0, 1.0);
 268     glMatrixMode(GL_MODELVIEW);
 269
 270     /* Map the texture */
 271     mesh_len = MESH_MAXSIZE*MESH_MAXSIZE*sizeof(struct vertex);
 272     mesh = cpu_physical_memory_map(s->regs[R_VERTICESADDR], &mesh_len, 0);
 273     if (mesh == NULL) {
 274         glDeleteTextures(1, &texture);
 275         glXMakeContextCurrent(s->dpy, None, None, NULL);
 276         glXDestroyPbuffer(s->dpy, pbuffer);
 277         return;
 278     }
 279
 280     tmu2_gl_map((struct vertex *)mesh,
 281         s->regs[R_TEXHRES], s->regs[R_TEXVRES],
 282         s->regs[R_HMESHLAST], s->regs[R_VMESHLAST],
 283         s->regs[R_DSTHOFFSET], s->regs[R_DSTVOFFSET],
 284         s->regs[R_DSTSQUAREW], s->regs[R_DSTSQUAREH]);
 285     cpu_physical_memory_unmap(mesh, mesh_len, 0, mesh_len);
 286
 287     /* Write back the OpenGL framebuffer to the QEMU framebuffer */
 288     fb_len = 2 * s->regs[R_DSTHRES] * s->regs[R_DSTVRES];
 289     fb = cpu_physical_memory_map(s->regs[R_DSTFBUF], &fb_len, 1);
 290     if (fb == NULL) {
 291         glDeleteTextures(1, &texture);
 292         glXMakeContextCurrent(s->dpy, None, None, NULL);
 293         glXDestroyPbuffer(s->dpy, pbuffer);
 294         return;
 295     }
 296
 297     glReadPixels(0, 0, s->regs[R_DSTHRES], s->regs[R_DSTVRES], GL_RGB,
 298             GL_UNSIGNED_SHORT_5_6_5, fb);
 299     cpu_physical_memory_unmap(fb, fb_len, 1, fb_len);
 300
 301     /* Free OpenGL allocs */
 302     glDeleteTextures(1, &texture);
 303     glXMakeContextCurrent(s->dpy, None, None, NULL);
 304     glXDestroyPbuffer(s->dpy, pbuffer);
 305
 306     s->regs[R_CTL] &= ~CTL_START_BUSY;
 307
 308     trace_milkymist_tmu2_pulse_irq();
 309     qemu_irq_pulse(s->irq);
 310 }
 311
 312 static uint32_t tmu2_read(void *opaque, target_phys_addr_t addr)
 313 {
 314     MilkymistTMU2State *s = opaque;
 315     uint32_t r = 0;
 316
 317     addr >>= 2;
 318     switch (addr) {
 319     case R_CTL:
 320     case R_HMESHLAST:
 321     case R_VMESHLAST:
 322     case R_BRIGHTNESS:
 323     case R_CHROMAKEY:
 324     case R_VERTICESADDR:
 325     case R_TEXFBUF:
 326     case R_TEXHRES:
 327     case R_TEXVRES:
 328     case R_TEXHMASK:
 329     case R_TEXVMASK:
 330     case R_DSTFBUF:
 331     case R_DSTHRES:
 332     case R_DSTVRES:
 333     case R_DSTHOFFSET:
 334     case R_DSTVOFFSET:
 335     case R_DSTSQUAREW:
 336     case R_DSTSQUAREH:
 337     case R_ALPHA:
 338         r = s->regs[addr];
 339         break;
 340
 341     default:
 342         error_report("milkymist_tmu2: read access to unknown register 0x"
 343                 TARGET_FMT_plx, addr << 2);
 344         break;
 345     }
 346
 347     trace_milkymist_tmu2_memory_read(addr << 2, r);
 348
 349     return r;
 350 }
 351
 352 static void tmu2_check_registers(MilkymistTMU2State *s)
 353 {
 354     if (s->regs[R_BRIGHTNESS] > MAX_BRIGHTNESS) {
 355         error_report("milkymist_tmu2: max brightness is %d", MAX_BRIGHTNESS);
 356     }
 357
 358     if (s->regs[R_ALPHA] > MAX_ALPHA) {
 359         error_report("milkymist_tmu2: max alpha is %d", MAX_ALPHA);
 360     }
 361
 362     if (s->regs[R_VERTICESADDR] & 0x07) {
 363         error_report("milkymist_tmu2: vertex mesh address has to be 64-bit "
 364                 "aligned");
 365     }
 366
 367     if (s->regs[R_TEXFBUF] & 0x01) {
 368         error_report("milkymist_tmu2: texture buffer address has to be "
 369                 "16-bit aligned");
 370     }
 371 }
 372
 373 static void tmu2_write(void *opaque, target_phys_addr_t addr, uint32_t value)
 374 {
 375     MilkymistTMU2State *s = opaque;
 376
 377     trace_milkymist_tmu2_memory_write(addr, value);
 378
 379     addr >>= 2;
 380     switch (addr) {
 381     case R_CTL:
 382         s->regs[addr] = value;
 383         if (value & CTL_START_BUSY) {
 384             tmu2_start(s);
 385         }
 386         break;
 387     case R_BRIGHTNESS:
 388     case R_HMESHLAST:
 389     case R_VMESHLAST:
 390     case R_CHROMAKEY:
 391     case R_VERTICESADDR:
 392     case R_TEXFBUF:
 393     case R_TEXHRES:
 394     case R_TEXVRES:
 395     case R_TEXHMASK:
 396     case R_TEXVMASK:
 397     case R_DSTFBUF:
 398     case R_DSTHRES:
 399     case R_DSTVRES:
 400     case R_DSTHOFFSET:
 401     case R_DSTVOFFSET:
 402     case R_DSTSQUAREW:
 403     case R_DSTSQUAREH:
 404     case R_ALPHA:
 405         s->regs[addr] = value;
 406         break;
 407
 408     default:
 409         error_report("milkymist_tmu2: write access to unknown register 0x"
 410                 TARGET_FMT_plx, addr << 2);
 411         break;
 412     }
 413
 414     tmu2_check_registers(s);
 415 }
 416
 417 static CPUReadMemoryFunc * const tmu2_read_fn[] = {
 418     NULL,
 419     NULL,
 420     &tmu2_read,
 421 };
 422
 423 static CPUWriteMemoryFunc * const tmu2_write_fn[] = {
 424     NULL,
 425     NULL,
 426     &tmu2_write,
 427 };
 428
 429 static void milkymist_tmu2_reset(DeviceState *d)
 430 {
 431     MilkymistTMU2State *s = container_of(d, MilkymistTMU2State, busdev.qdev);
 432     int i;
 433
 434     for (i = 0; i < R_MAX; i++) {
 435         s->regs[i] = 0;
 436     }
 437 }
 438
 439 static int milkymist_tmu2_init(SysBusDevice *dev)
 440 {
 441     MilkymistTMU2State *s = FROM_SYSBUS(typeof(*s), dev);
 442     int tmu2_regs;
 443
 444     if (tmu2_glx_init(s)) {
 445         return 1;
 446     }
 447
 448     sysbus_init_irq(dev, &s->irq);
 449
 450     tmu2_regs = cpu_register_io_memory(tmu2_read_fn, tmu2_write_fn, s,
 451             DEVICE_NATIVE_ENDIAN);
 452     sysbus_init_mmio(dev, R_MAX * 4, tmu2_regs);
 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 SysBusDeviceInfo milkymist_tmu2_info = {
 469     .init = milkymist_tmu2_init,
 470     .qdev.name  = "milkymist-tmu2",
 471     .qdev.size  = sizeof(MilkymistTMU2State),
 472     .qdev.vmsd  = &vmstate_milkymist_tmu2,
 473     .qdev.reset = milkymist_tmu2_reset,
 474 };
 475
 476 static void milkymist_tmu2_register(void)
 477 {
 478     sysbus_register_withprop(&milkymist_tmu2_info);
 479 }
 480
 481 device_init(milkymist_tmu2_register)