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
  74     uint8_t passthrough;
  75
  76
  77     struct v3_console_ops * ops;
  78     void * private_data;
  79
  80
  81
  82 };
  83
  84
  85
  86
  87 static void passthrough_in(uint16_t port, void * src, uint_t length) {
  88     switch (length) {
  89         case 1:
  90             *(uint8_t *)src = v3_inb(port);
  91             break;
  92         case 2:
  93             *(uint16_t *)src = v3_inw(port);
  94             break;
  95         case 4:
  96             *(uint32_t *)src = v3_indw(port);
  97             break;
  98         default:
  99             break;
 100     }
 101 }
 102
 103
 104 static void passthrough_out(uint16_t port, void * src, uint_t length) {
 105     switch (length) {
 106         case 1:
 107             v3_outb(port, *(uint8_t *)src);
 108             break;
 109         case 2:
 110             v3_outw(port, *(uint16_t *)src);
 111             break;
 112         case 4:
 113             v3_outdw(port, *(uint32_t *)src);
 114             break;
 115         default:
 116             break;
 117     }
 118 }
 119
 120 static int video_write_mem(struct guest_info * core, addr_t guest_addr, void * dest, uint_t length, void * priv_data) {
 121     struct vm_device * dev = (struct vm_device *)priv_data;
 122     struct video_internal * state = (struct video_internal *)dev->private_data;
 123     uint_t fb_offset = guest_addr - START_ADDR;
 124     uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL;
 125     uint_t screen_length;
 126
 127     PrintDebug("Guest address: %p length = %d, fb_offset=%d, screen_offset=%d\n",
 128                (void *)guest_addr, length, fb_offset, screen_byte_offset);
 129
 130     if (state->passthrough) {
 131         memcpy(state->framebuf + fb_offset, V3_VAddr((void *)guest_addr), length);
 132     }
 133
 134     if ((fb_offset >= screen_byte_offset) && (fb_offset < (screen_byte_offset + SCREEN_SIZE))) {
 135         uint_t screen_pos = fb_offset - screen_byte_offset;
 136         uint_t x = (screen_pos % BYTES_PER_ROW) / BYTES_PER_COL;
 137         uint_t y = screen_pos / BYTES_PER_ROW;
 138         PrintDebug("Sending Screen update\n");
 139
 140         if (state->ops) {
 141             PrintDebug("\tcalling update_screen()\n");
 142
 143             /* avoid updates past end of screen */
 144             screen_length = SCREEN_SIZE - screen_byte_offset;
 145             if (screen_length > length) screen_length = length;
 146             state->ops->update_screen(x, y, screen_length, state->private_data);
 147         }
 148     }
 149
 150     return length;
 151 }
 152
 153 static int video_read_port(struct guest_info * core, uint16_t port, void * dest, uint_t length, void * priv_data) {
 154     struct video_internal * video_state = priv_data;
 155
 156
 157     PrintDebug("Video: Read port 0x%x\n", port);
 158
 159     if (video_state->passthrough) {
 160         passthrough_in(port, dest, length);
 161     }
 162
 163     return length;
 164 }
 165
 166
 167
 168 static int video_write_port(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 169     struct video_internal * video_state = priv_data;
 170
 171
 172     PrintDebug("Video: write port 0x%x...\n", port);
 173
 174     if (video_state->passthrough) {
 175         passthrough_out(port, src, length);
 176     }
 177
 178     return length;
 179 }
 180
 181
 182
 183 static int crtc_data_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 184     struct video_internal * video_state = priv_data;
 185     uint8_t val = *(uint8_t *)src;
 186     uint_t index = video_state->crtc_index_reg;
 187
 188     if (length != 1) {
 189         PrintError("Invalid write length for port 0x%x\n", port);
 190         return -1;
 191     }
 192
 193     PrintDebug("Video: write on port 0x%x... (val=0x%x)\n", port, val);
 194
 195     video_state->crtc_data_regs[index] = val;
 196
 197     switch (index) {
 198         case 0x0c: { // scroll high byte
 199             uint16_t tmp_val = val;
 200             video_state->tmp_screen_offset = ((tmp_val << 8) & 0xff00);
 201             break;
 202         }
 203         case 0x0d: {  // Scroll low byte
 204             int diff = 0;
 205
 206             video_state->tmp_screen_offset += val;
 207             diff = (video_state->tmp_screen_offset - video_state->screen_offset) / NUM_COLS;
 208
 209             // Update the true offset value
 210             video_state->screen_offset = video_state->tmp_screen_offset;
 211             video_state->tmp_screen_offset = 0;
 212
 213             PrintDebug("Scroll lines = %d, new screen offset=%d\n",
 214                        diff, video_state->screen_offset * BYTES_PER_COL);
 215
 216             if (video_state->ops) {
 217                 if (video_state->ops->scroll(diff, video_state->private_data) == -1) {
 218                     PrintError("Error sending scroll event\n");
 219                     return -1;
 220                 }
 221             }
 222             break;
 223         }
 224         case 0x0E: {  // Cursor adjustment High byte
 225             uint16_t tmp_val = val;
 226             video_state->cursor_offset = ((tmp_val << 8) & 0xff00);
 227
 228             break;
 229         }
 230         case 0x0F: { // cursor adjustment low byte
 231             uint_t x = 0;
 232             uint_t y = 0;
 233
 234             video_state->cursor_offset += val;
 235
 236             x = video_state->cursor_offset % NUM_COLS;
 237             y = (video_state->cursor_offset - video_state->screen_offset) / NUM_COLS;
 238
 239             PrintDebug("New Cursor Location; X=%d Y=%d\n", x, y);
 240
 241             if (video_state->ops) {
 242                 if (video_state->ops->update_cursor(x, y, video_state->private_data) == -1) {
 243                     PrintError("Error updating cursor\n");
 244                     return -1;
 245                 }
 246             }
 247
 248             break;
 249         }
 250         default:
 251             break;
 252     }
 253
 254     if (video_state->passthrough) {
 255         passthrough_out(port, src, length);
 256     }
 257
 258     return length;
 259 }
 260
 261
 262 static int crtc_index_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * priv_data) {
 263     struct video_internal * video_state = priv_data;
 264
 265     if (length > 2) {
 266         PrintError("Invalid write length for crtc index register port: %d (0x%x)\n",
 267                    port, port);
 268         return -1;
 269     }
 270
 271
 272     video_state->crtc_index_reg = *(uint8_t *)src;
 273
 274     // Only do the passthrough IO for the first byte
 275     // the second byte will be done in the data register handler
 276     if (video_state->passthrough) {
 277         passthrough_out(port, src, 1);
 278     }
 279
 280     if (length == 2) {
 281         if (crtc_data_write(core, port + 1, src + 1, length - 1, video_state) != (length - 1)) {
 282             PrintError("could not handle implicit crtc data write\n");
 283             return -1;
 284         }
 285     }
 286
 287     return length;
 288 }
 289
 290
 291
 292 int v3_cons_get_fb(struct vm_device * frontend_dev, uint8_t * dst, uint_t offset, uint_t length) {
 293     struct video_internal * state = (struct video_internal *)frontend_dev->private_data;
 294     uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL;
 295
 296     PrintDebug("Getting framebuffer for screen; framebuf=%p, screen_offset=%d, offset=%d, length=%d\n",
 297                state->framebuf, screen_byte_offset, offset, length);
 298
 299     V3_ASSERT(screen_byte_offset <= FRAMEBUF_SIZE - SCREEN_SIZE);
 300     V3_ASSERT(offset < SCREEN_SIZE);
 301     V3_ASSERT(length <= SCREEN_SIZE);
 302     V3_ASSERT(offset + length <= SCREEN_SIZE);
 303     memcpy(dst, state->framebuf + screen_byte_offset + offset, length);
 304
 305     return 0;
 306 }
 307
 308
 309
 310 static int free_device(struct vm_device * dev) {
 311     struct video_internal * video_state = (struct video_internal *)dev->private_data;
 312
 313     if (video_state->framebuf_pa) {
 314         V3_FreePages((void *)(video_state->framebuf_pa), (FRAMEBUF_SIZE / 4096));
 315     }
 316
 317     v3_unhook_mem(dev->vm, V3_MEM_CORE_ANY, START_ADDR);
 318
 319
 320     V3_Free(video_state);
 321
 322     return 0;
 323 }
 324
 325
 326 static struct v3_device_ops dev_ops = {
 327     .free = free_device,
 328 };
 329
 330 static int cga_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 331     struct video_internal * video_state = NULL;
 332     char * dev_id = v3_cfg_val(cfg, "ID");
 333     char * passthrough_str = v3_cfg_val(cfg, "passthrough");
 334
 335     PrintDebug("video: init_device\n");
 336
 337     video_state = (struct video_internal *)V3_Malloc(sizeof(struct video_internal));
 338     memset(video_state, 0, sizeof(struct video_internal));
 339
 340     struct vm_device * dev = v3_allocate_device(dev_id, &dev_ops, video_state);
 341
 342     if (v3_attach_device(vm, dev) == -1) {
 343         PrintError("Could not attach device %s\n", dev_id);
 344         V3_Free(video_state);
 345         return -1;
 346     }
 347
 348     video_state->framebuf_pa = (addr_t)V3_AllocPages(FRAMEBUF_SIZE / 4096);
 349     video_state->framebuf = V3_VAddr((void *)(video_state->framebuf_pa));
 350     memset(video_state->framebuf, 0, FRAMEBUF_SIZE);
 351
 352     PrintDebug("PA of array: %p\n", (void *)(video_state->framebuf_pa));
 353
 354     if ((passthrough_str != NULL) &&
 355         (strcasecmp(passthrough_str, "enable") == 0)) {;
 356         video_state->passthrough = 1;
 357     }
 358
 359
 360     if (video_state->passthrough) {
 361         PrintDebug("Enabling CGA Passthrough\n");
 362         if (v3_hook_write_mem(vm, V3_MEM_CORE_ANY, START_ADDR, END_ADDR,
 363                               START_ADDR, &video_write_mem, dev) == -1) {
 364             PrintDebug("\n\nVideo Hook failed.\n\n");
 365         }
 366     } else {
 367         if (v3_hook_write_mem(vm, V3_MEM_CORE_ANY, START_ADDR, END_ADDR,
 368                               video_state->framebuf_pa, &video_write_mem, dev) == -1) {
 369             PrintDebug("\n\nVideo Hook failed.\n\n");
 370         }
 371     }
 372
 373
 374     v3_dev_hook_io(dev, 0x3b0, &video_read_port, &video_write_port);
 375     v3_dev_hook_io(dev, 0x3b1, &video_read_port, &video_write_port);
 376     v3_dev_hook_io(dev, 0x3b2, &video_read_port, &video_write_port);
 377     v3_dev_hook_io(dev, 0x3b3, &video_read_port, &video_write_port);
 378     v3_dev_hook_io(dev, 0x3b4, &video_read_port, &video_write_port);
 379     v3_dev_hook_io(dev, 0x3b5, &video_read_port, &video_write_port);
 380     v3_dev_hook_io(dev, 0x3b6, &video_read_port, &video_write_port);
 381     v3_dev_hook_io(dev, 0x3b7, &video_read_port, &video_write_port);
 382     v3_dev_hook_io(dev, 0x3b8, &video_read_port, &video_write_port);
 383     v3_dev_hook_io(dev, 0x3b9, &video_read_port, &video_write_port);
 384     v3_dev_hook_io(dev, 0x3ba, &video_read_port, &video_write_port);
 385     v3_dev_hook_io(dev, 0x3bb, &video_read_port, &video_write_port);
 386     v3_dev_hook_io(dev, 0x3c0, &video_read_port, &video_write_port);
 387     v3_dev_hook_io(dev, 0x3c1, &video_read_port, &video_write_port);
 388     v3_dev_hook_io(dev, 0x3c2, &video_read_port, &video_write_port);
 389     v3_dev_hook_io(dev, 0x3c3, &video_read_port, &video_write_port);
 390     v3_dev_hook_io(dev, 0x3c4, &video_read_port, &video_write_port);
 391     v3_dev_hook_io(dev, 0x3c5, &video_read_port, &video_write_port);
 392     v3_dev_hook_io(dev, 0x3c6, &video_read_port, &video_write_port);
 393     v3_dev_hook_io(dev, 0x3c7, &video_read_port, &video_write_port);
 394     v3_dev_hook_io(dev, 0x3c8, &video_read_port, &video_write_port);
 395     v3_dev_hook_io(dev, 0x3c9, &video_read_port, &video_write_port);
 396     v3_dev_hook_io(dev, 0x3ca, &video_read_port, &video_write_port);
 397     v3_dev_hook_io(dev, 0x3cb, &video_read_port, &video_write_port);
 398     v3_dev_hook_io(dev, 0x3cc, &video_read_port, &video_write_port);
 399     v3_dev_hook_io(dev, 0x3cd, &video_read_port, &video_write_port);
 400     v3_dev_hook_io(dev, 0x3ce, &video_read_port, &video_write_port);
 401     v3_dev_hook_io(dev, 0x3cf, &video_read_port, &video_write_port);
 402     v3_dev_hook_io(dev, 0x3d0, &video_read_port, &video_write_port);
 403     v3_dev_hook_io(dev, 0x3d1, &video_read_port, &video_write_port);
 404     v3_dev_hook_io(dev, 0x3d2, &video_read_port, &video_write_port);
 405     v3_dev_hook_io(dev, 0x3d3, &video_read_port, &video_write_port);
 406     v3_dev_hook_io(dev, 0x3d4, &video_read_port, &crtc_index_write);
 407     v3_dev_hook_io(dev, 0x3d5, &video_read_port, &crtc_data_write);
 408     v3_dev_hook_io(dev, 0x3d6, &video_read_port, &video_write_port);
 409     v3_dev_hook_io(dev, 0x3d7, &video_read_port, &video_write_port);
 410     v3_dev_hook_io(dev, 0x3d8, &video_read_port, &video_write_port);
 411     v3_dev_hook_io(dev, 0x3d9, &video_read_port, &video_write_port);
 412     v3_dev_hook_io(dev, 0x3da, &video_read_port, &video_write_port);
 413     v3_dev_hook_io(dev, 0x3db, &video_read_port, &video_write_port);
 414     v3_dev_hook_io(dev, 0x3dc, &video_read_port, &video_write_port);
 415     v3_dev_hook_io(dev, 0x3dd, &video_read_port, &video_write_port);
 416     v3_dev_hook_io(dev, 0x3de, &video_read_port, &video_write_port);
 417     v3_dev_hook_io(dev, 0x3df, &video_read_port, &video_write_port);
 418
 419
 420     return 0;
 421 }
 422
 423 device_register("CGA_VIDEO", cga_init);
 424
 425
 426 int v3_console_register_cga(struct vm_device * cga_dev, struct v3_console_ops * ops, void * private_data) {
 427     struct video_internal * video_state = (struct video_internal *)cga_dev->private_data;
 428
 429     video_state->ops = ops;
 430     video_state->private_data = private_data;
 431
 432     return 0;
 433 }