palacios/src/devices/cga.c

   1 /*
   2  * This file is part of the Palacios Virtual Machine Monitor developed
   3  * by the V3VEE Project with funding from the United States National
   4  * Science Foundation and the Department of Energy.
   5  *
   6  * The V3VEE Project is a joint project between Northwestern University
   7  * and the University of New Mexico.  You can find out more at
   8  * http://www.v3vee.org
   9  *
  10  * Copyright (c) 2009, Robert Deloatch <rtdeloatch@gmail.com>
  11  * Copyright (c) 2009, Steven Jaconette <stevenjaconette2007@u.northwestern.edu>
  12  * Copyright (c) 2009, The V3VEE Project <http://www.v3vee.org>
  13  * All rights reserved.
  14  *
  15  * Author: Robdert Deloatch <rtdeloatch@gmail.com>
  16  *         Steven Jaconette <stevenjaconette2007@u.northwestern.edu>
  17  *
  18  * This is free software.  You are permitted to use,
  19  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
  20  */
  21
  22 #include <palacios/vmm.h>
  23 #include <palacios/vmm_dev_mgr.h>
  24 #include <palacios/vmm_emulator.h>
  25 #include <palacios/vm_guest_mem.h>
  26 #include <palacios/vmm_io.h>
  27
  28 #include <devices/console.h>
  29
  30
  31
  32
  33 #ifndef DEBUG_CGA
  34 #undef PrintDebug
  35 #define PrintDebug(fmt, args...)
  36 #endif
  37
  38
  39 #define START_ADDR 0xB8000
  40 #define END_ADDR 0xC0000
  41
  42 #define FRAMEBUF_SIZE (END_ADDR - START_ADDR)
  43 #define SCREEN_SIZE 4000
  44
  45 #define BASE_CGA_PORT 0x3B0
  46
  47 #define NUM_COLS 80
  48 #define NUM_ROWS 25
  49 #define BYTES_PER_ROW (NUM_COLS * 2)
  50 #define BYTES_PER_COL 2
  51
  52
  53 struct video_internal {
  54     uint8_t * framebuf;
  55     addr_t framebuf_pa;
  56
  57     // These store the values for unhandled ports, in case of a read op
  58     uint8_t port_store[44];
  59
  60
  61     uint8_t crtc_index_reg;          // io port 3D4
  62     uint8_t crtc_data_regs[25];      // io port 3D5
  63
  64     /* IMPORTANT: These are column offsets _NOT_ byte offsets */
  65     uint16_t screen_offset; // relative to the framebuffer
  66     uint16_t cursor_offset; // relative to the framebuffer
  67     /* ** */
  68
  69     // updating the screen offset is not atomic,
  70     // so we need a temp variable to hold the partial update
  71     uint16_t tmp_screen_offset;
  72
  73     struct vm_device * dev;
  74
  75
  76     uint8_t passthrough;
  77
  78
  79     struct v3_console_ops * ops;
  80     void * private_data;
  81
  82
  83
  84 };
  85
  86
  87
  88
  89 static void passthrough_in(uint16_t port, void * src, uint_t length) {
  90     switch (length) {
  91         case 1:
  92             *(uint8_t *)src = v3_inb(port);
  93             break;
  94         case 2:
  95             *(uint16_t *)src = v3_inw(port);
  96             break;
  97         case 4:
  98             *(uint32_t *)src = v3_indw(port);
  99             break;
 100         default:
 101             break;
 102     }
 103 }
 104
 105
 106 static void passthrough_out(uint16_t port, void * src, uint_t length) {
 107     switch (length) {
 108         case 1:
 109             v3_outb(port, *(uint8_t *)src);
 110             break;
 111         case 2:
 112             v3_outw(port, *(uint16_t *)src);
 113             break;
 114         case 4:
 115             v3_outdw(port, *(uint32_t *)src);
 116             break;
 117         default:
 118             break;
 119     }
 120 }
 121
 122 static int video_write_mem(struct guest_info * core, addr_t guest_addr, void * dest, uint_t length, void * priv_data) {
 123     struct vm_device * dev = (struct vm_device *)priv_data;
 124     struct video_internal * state = (struct video_internal *)dev->private_data;
 125     uint_t fb_offset = guest_addr - START_ADDR;
 126     uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL;
 127     uint_t screen_length;
 128
 129     PrintDebug("Guest address: %p length = %d, fb_offset=%d, screen_offset=%d\n",
 130                (void *)guest_addr, length, fb_offset, screen_byte_offset);
 131
 132     if (state->passthrough) {
 133         memcpy(state->framebuf + fb_offset, V3_VAddr((void *)guest_addr), length);
 134     }
 135
 136     if ((fb_offset >= screen_byte_offset) && (fb_offset < (screen_byte_offset + SCREEN_SIZE))) {
 137         uint_t screen_pos = fb_offset - screen_byte_offset;
 138         uint_t x = (screen_pos % BYTES_PER_ROW) / BYTES_PER_COL;
 139         uint_t y = screen_pos / BYTES_PER_ROW;
 140         PrintDebug("Sending Screen update\n");
 141
 142         if (state->ops) {
 143             PrintDebug("\tcalling update_screen()\n");
 144
 145             /* avoid updates past end of screen */
 146             screen_length = SCREEN_SIZE - screen_byte_offset;
 147             if (screen_length > length) screen_length = length;
 148             state->ops->update_screen(x, y, screen_length, state->private_data);
 149         }
 150     }
 151
 152     return length;
 153 }
 154
 155 static int video_read_port(struct guest_info * core, uint16_t port, void * dest, uint_t length, void * priv_data) {
 156     struct video_internal * video_state = priv_data;
 157
 158
 159     PrintDebug("Video: Read port 0x%x\n", port);
 160
 161     if (video_state->passthrough) {
 162         passthrough_in(port, dest, length);
 163     }
 164
 165     return length;
 166 }
 167
 168
 169
 170 static int video_write_port(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 171     struct video_internal * video_state = priv_data;
 172
 173
 174     PrintDebug("Video: write port 0x%x...\n", port);
 175
 176     if (video_state->passthrough) {
 177         passthrough_out(port, src, length);
 178     }
 179
 180     return length;
 181 }
 182
 183
 184
 185 static int crtc_data_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 186     struct video_internal * video_state = priv_data;
 187     uint8_t val = *(uint8_t *)src;
 188     uint_t index = video_state->crtc_index_reg;
 189
 190     if (length != 1) {
 191         PrintError("Invalid write length for port 0x%x\n", port);
 192         return -1;
 193     }
 194
 195     PrintDebug("Video: write on port 0x%x... (val=0x%x)\n", port, val);
 196
 197     video_state->crtc_data_regs[index] = val;
 198
 199     switch (index) {
 200         case 0x0c: { // scroll high byte
 201             uint16_t tmp_val = val;
 202             video_state->tmp_screen_offset = ((tmp_val << 8) & 0xff00);
 203             break;
 204         }
 205         case 0x0d: {  // Scroll low byte
 206             int diff = 0;
 207
 208             video_state->tmp_screen_offset += val;
 209             diff = (video_state->tmp_screen_offset - video_state->screen_offset) / NUM_COLS;
 210
 211             // Update the true offset value
 212             video_state->screen_offset = video_state->tmp_screen_offset;
 213             video_state->tmp_screen_offset = 0;
 214
 215             PrintDebug("Scroll lines = %d, new screen offset=%d\n",
 216                        diff, video_state->screen_offset * BYTES_PER_COL);
 217
 218             if (video_state->ops) {
 219                 if (video_state->ops->scroll(diff, video_state->private_data) == -1) {
 220                     PrintError("Error sending scroll event\n");
 221                     return -1;
 222                 }
 223             }
 224             break;
 225         }
 226         case 0x0E: {  // Cursor adjustment High byte
 227             uint16_t tmp_val = val;
 228             video_state->cursor_offset = ((tmp_val << 8) & 0xff00);
 229
 230             break;
 231         }
 232         case 0x0F: { // cursor adjustment low byte
 233             uint_t x = 0;
 234             uint_t y = 0;
 235
 236             video_state->cursor_offset += val;
 237
 238             x = video_state->cursor_offset % NUM_COLS;
 239             y = (video_state->cursor_offset - video_state->screen_offset) / NUM_COLS;
 240
 241             PrintDebug("New Cursor Location; X=%d Y=%d\n", x, y);
 242
 243             if (video_state->ops) {
 244                 if (video_state->ops->update_cursor(x, y, video_state->private_data) == -1) {
 245                     PrintError("Error updating cursor\n");
 246                     return -1;
 247                 }
 248             }
 249
 250             break;
 251         }
 252         default:
 253             break;
 254     }
 255
 256     if (video_state->passthrough) {
 257         passthrough_out(port, src, length);
 258     }
 259
 260     return length;
 261 }
 262
 263
 264 static int crtc_index_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 265     struct video_internal * video_state = priv_data;
 266
 267     if (length > 2) {
 268         PrintError("Invalid write length for crtc index register port: %d (0x%x)\n",
 269                    port, port);
 270         return -1;
 271     }
 272
 273
 274     video_state->crtc_index_reg = *(uint8_t *)src;
 275
 276     // Only do the passthrough IO for the first byte
 277     // the second byte will be done in the data register handler
 278     if (video_state->passthrough) {
 279         passthrough_out(port, src, 1);
 280     }
 281
 282     if (length == 2) {
 283         if (crtc_data_write(core, port + 1, src + 1, length - 1, video_state) != (length - 1)) {
 284             PrintError("could not handle implicit crtc data write\n");
 285             return -1;
 286         }
 287     }
 288
 289     return length;
 290 }
 291
 292
 293
 294 int v3_cons_get_fb(struct vm_device * frontend_dev, uint8_t * dst, uint_t offset, uint_t length) {
 295     struct video_internal * state = (struct video_internal *)frontend_dev->private_data;
 296     uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL;
 297
 298     PrintDebug("Getting framebuffer for screen; framebuf=%p, screen_offset=%d, offset=%d, length=%d\n",
 299                state->framebuf, screen_byte_offset, offset, length);
 300
 301     V3_ASSERT(screen_byte_offset <= FRAMEBUF_SIZE - SCREEN_SIZE);
 302     V3_ASSERT(offset < SCREEN_SIZE);
 303     V3_ASSERT(length <= SCREEN_SIZE);
 304     V3_ASSERT(offset + length <= SCREEN_SIZE);
 305     memcpy(dst, state->framebuf + screen_byte_offset + offset, length);
 306
 307     return 0;
 308 }
 309
 310
 311
 312 static int free_device(struct video_internal * video_state) {
 313
 314     if (video_state->framebuf_pa) {
 315         V3_FreePages((void *)(video_state->framebuf_pa), (FRAMEBUF_SIZE / 4096));
 316     }
 317
 318     v3_unhook_mem(video_state->dev->vm, V3_MEM_CORE_ANY, START_ADDR);
 319
 320
 321     V3_Free(video_state);
 322
 323     return 0;
 324 }
 325
 326
 327 static struct v3_device_ops dev_ops = {
 328     .free = (int (*)(void *))free_device,
 329 };
 330
 331 static int cga_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 332     struct video_internal * video_state = NULL;
 333     char * dev_id = v3_cfg_val(cfg, "ID");
 334     char * passthrough_str = v3_cfg_val(cfg, "passthrough");
 335     int ret = 0;
 336
 337     PrintDebug("video: init_device\n");
 338
 339     video_state = (struct video_internal *)V3_Malloc(sizeof(struct video_internal));
 340     memset(video_state, 0, sizeof(struct video_internal));
 341
 342     struct vm_device * dev = v3_add_device(vm, dev_id, &dev_ops, video_state);
 343
 344     if (dev == NULL) {
 345         PrintError("Could not attach device %s\n", dev_id);
 346         V3_Free(video_state);
 347         return -1;
 348     }
 349
 350     video_state->dev = dev;
 351
 352     video_state->framebuf_pa = (addr_t)V3_AllocPages(FRAMEBUF_SIZE / 4096);
 353     video_state->framebuf = V3_VAddr((void *)(video_state->framebuf_pa));
 354     memset(video_state->framebuf, 0, FRAMEBUF_SIZE);
 355
 356     PrintDebug("PA of array: %p\n", (void *)(video_state->framebuf_pa));
 357
 358     if ((passthrough_str != NULL) &&
 359         (strcasecmp(passthrough_str, "enable") == 0)) {;
 360         video_state->passthrough = 1;
 361     }
 362
 363
 364     if (video_state->passthrough) {
 365         PrintDebug("Enabling CGA Passthrough\n");
 366         if (v3_hook_write_mem(vm, V3_MEM_CORE_ANY, START_ADDR, END_ADDR,
 367                               START_ADDR, &video_write_mem, dev) == -1) {
 368             PrintDebug("\n\nVideo Hook failed.\n\n");
 369         }
 370     } else {
 371         if (v3_hook_write_mem(vm, V3_MEM_CORE_ANY, START_ADDR, END_ADDR,
 372                               video_state->framebuf_pa, &video_write_mem, dev) == -1) {
 373             PrintDebug("\n\nVideo Hook failed.\n\n");
 374         }
 375     }
 376
 377
 378     ret |= v3_dev_hook_io(dev, 0x3b0, &video_read_port, &video_write_port);
 379     ret |= v3_dev_hook_io(dev, 0x3b1, &video_read_port, &video_write_port);
 380     ret |= v3_dev_hook_io(dev, 0x3b2, &video_read_port, &video_write_port);
 381     ret |= v3_dev_hook_io(dev, 0x3b3, &video_read_port, &video_write_port);
 382     ret |= v3_dev_hook_io(dev, 0x3b4, &video_read_port, &video_write_port);
 383     ret |= v3_dev_hook_io(dev, 0x3b5, &video_read_port, &video_write_port);
 384     ret |= v3_dev_hook_io(dev, 0x3b6, &video_read_port, &video_write_port);
 385     ret |= v3_dev_hook_io(dev, 0x3b7, &video_read_port, &video_write_port);
 386     ret |= v3_dev_hook_io(dev, 0x3b8, &video_read_port, &video_write_port);
 387     ret |= v3_dev_hook_io(dev, 0x3b9, &video_read_port, &video_write_port);
 388     ret |= v3_dev_hook_io(dev, 0x3ba, &video_read_port, &video_write_port);
 389     ret |= v3_dev_hook_io(dev, 0x3bb, &video_read_port, &video_write_port);
 390     ret |= v3_dev_hook_io(dev, 0x3c0, &video_read_port, &video_write_port);
 391     ret |= v3_dev_hook_io(dev, 0x3c1, &video_read_port, &video_write_port);
 392     ret |= v3_dev_hook_io(dev, 0x3c2, &video_read_port, &video_write_port);
 393     ret |= v3_dev_hook_io(dev, 0x3c3, &video_read_port, &video_write_port);
 394     ret |= v3_dev_hook_io(dev, 0x3c4, &video_read_port, &video_write_port);
 395     ret |= v3_dev_hook_io(dev, 0x3c5, &video_read_port, &video_write_port);
 396     ret |= v3_dev_hook_io(dev, 0x3c6, &video_read_port, &video_write_port);
 397     ret |= v3_dev_hook_io(dev, 0x3c7, &video_read_port, &video_write_port);
 398     ret |= v3_dev_hook_io(dev, 0x3c8, &video_read_port, &video_write_port);
 399     ret |= v3_dev_hook_io(dev, 0x3c9, &video_read_port, &video_write_port);
 400     ret |= v3_dev_hook_io(dev, 0x3ca, &video_read_port, &video_write_port);
 401     ret |= v3_dev_hook_io(dev, 0x3cb, &video_read_port, &video_write_port);
 402     ret |= v3_dev_hook_io(dev, 0x3cc, &video_read_port, &video_write_port);
 403     ret |= v3_dev_hook_io(dev, 0x3cd, &video_read_port, &video_write_port);
 404     ret |= v3_dev_hook_io(dev, 0x3ce, &video_read_port, &video_write_port);
 405     ret |= v3_dev_hook_io(dev, 0x3cf, &video_read_port, &video_write_port);
 406     ret |= v3_dev_hook_io(dev, 0x3d0, &video_read_port, &video_write_port);
 407     ret |= v3_dev_hook_io(dev, 0x3d1, &video_read_port, &video_write_port);
 408     ret |= v3_dev_hook_io(dev, 0x3d2, &video_read_port, &video_write_port);
 409     ret |= v3_dev_hook_io(dev, 0x3d3, &video_read_port, &video_write_port);
 410     ret |= v3_dev_hook_io(dev, 0x3d4, &video_read_port, &crtc_index_write);
 411     ret |= v3_dev_hook_io(dev, 0x3d5, &video_read_port, &crtc_data_write);
 412     ret |= v3_dev_hook_io(dev, 0x3d6, &video_read_port, &video_write_port);
 413     ret |= v3_dev_hook_io(dev, 0x3d7, &video_read_port, &video_write_port);
 414     ret |= v3_dev_hook_io(dev, 0x3d8, &video_read_port, &video_write_port);
 415     ret |= v3_dev_hook_io(dev, 0x3d9, &video_read_port, &video_write_port);
 416     ret |= v3_dev_hook_io(dev, 0x3da, &video_read_port, &video_write_port);
 417     ret |= v3_dev_hook_io(dev, 0x3db, &video_read_port, &video_write_port);
 418     ret |= v3_dev_hook_io(dev, 0x3dc, &video_read_port, &video_write_port);
 419     ret |= v3_dev_hook_io(dev, 0x3dd, &video_read_port, &video_write_port);
 420     ret |= v3_dev_hook_io(dev, 0x3de, &video_read_port, &video_write_port);
 421     ret |= v3_dev_hook_io(dev, 0x3df, &video_read_port, &video_write_port);
 422
 423     if (ret != 0) {
 424         PrintError("Error allocating cga io port\n");
 425         v3_remove_device(dev);
 426         return -1;
 427     }
 428
 429     return 0;
 430 }
 431
 432 device_register("CGA_VIDEO", cga_init);
 433
 434
 435 int v3_console_register_cga(struct vm_device * cga_dev, struct v3_console_ops * ops, void * private_data) {
 436     struct video_internal * video_state = (struct video_internal *)cga_dev->private_data;
 437
 438     video_state->ops = ops;
 439     video_state->private_data = private_data;
 440
 441     return 0;
 442 }