kernel/drivers/gpu/drm/via/via_dma.c

   1 /* via_dma.c -- DMA support for the VIA Unichrome/Pro
   2  *
   3  * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Copyright 2004 Digeo, Inc., Palo Alto, CA, U.S.A.
   7  * All Rights Reserved.
   8  *
   9  * Copyright 2004 The Unichrome project.
  10  * All Rights Reserved.
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a
  13  * copy of this software and associated documentation files (the "Software"),
  14  * to deal in the Software without restriction, including without limitation
  15  * the rights to use, copy, modify, merge, publish, distribute, sub license,
  16  * and/or sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice (including the
  20  * next paragraph) shall be included in all copies or substantial portions
  21  * of the Software.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  24  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  25  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  26  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  27  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  28  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  29  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  30  *
  31  * Authors:
  32  *    Tungsten Graphics,
  33  *    Erdi Chen,
  34  *    Thomas Hellstrom.
  35  */
  36
  37 #include <drm/drmP.h>
  38 #include <drm/via_drm.h>
  39 #include "via_drv.h"
  40 #include "via_3d_reg.h"
  41
  42 #define CMDBUF_ALIGNMENT_SIZE   (0x100)
  43 #define CMDBUF_ALIGNMENT_MASK   (0x0ff)
  44
  45 /* defines for VIA 3D registers */
  46 #define VIA_REG_STATUS          0x400
  47 #define VIA_REG_TRANSET         0x43C
  48 #define VIA_REG_TRANSPACE       0x440
  49
  50 /* VIA_REG_STATUS(0x400): Engine Status */
  51 #define VIA_CMD_RGTR_BUSY       0x00000080      /* Command Regulator is busy */
  52 #define VIA_2D_ENG_BUSY         0x00000001      /* 2D Engine is busy */
  53 #define VIA_3D_ENG_BUSY         0x00000002      /* 3D Engine is busy */
  54 #define VIA_VR_QUEUE_BUSY       0x00020000      /* Virtual Queue is busy */
  55
  56 #define SetReg2DAGP(nReg, nData) {                              \
  57         *((uint32_t *)(vb)) = ((nReg) >> 2) | HALCYON_HEADER1;  \
  58         *((uint32_t *)(vb) + 1) = (nData);                      \
  59         vb = ((uint32_t *)vb) + 2;                              \
  60         dev_priv->dma_low += 8;                                 \
  61 }
  62
  63 #define via_flush_write_combine() mb()
  64
  65 #define VIA_OUT_RING_QW(w1, w2) do {            \
  66         *vb++ = (w1);                           \
  67         *vb++ = (w2);                           \
  68         dev_priv->dma_low += 8;                 \
  69 } while (0)
  70
  71 static void via_cmdbuf_start(drm_via_private_t *dev_priv);
  72 static void via_cmdbuf_pause(drm_via_private_t *dev_priv);
  73 static void via_cmdbuf_reset(drm_via_private_t *dev_priv);
  74 static void via_cmdbuf_rewind(drm_via_private_t *dev_priv);
  75 static int via_wait_idle(drm_via_private_t *dev_priv);
  76 static void via_pad_cache(drm_via_private_t *dev_priv, int qwords);
  77
  78 /*
  79  * Free space in command buffer.
  80  */
  81
  82 static uint32_t via_cmdbuf_space(drm_via_private_t *dev_priv)
  83 {
  84         uint32_t agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
  85         uint32_t hw_addr = *(dev_priv->hw_addr_ptr) - agp_base;
  86
  87         return ((hw_addr <= dev_priv->dma_low) ?
  88                 (dev_priv->dma_high + hw_addr - dev_priv->dma_low) :
  89                 (hw_addr - dev_priv->dma_low));
  90 }
  91
  92 /*
  93  * How much does the command regulator lag behind?
  94  */
  95
  96 static uint32_t via_cmdbuf_lag(drm_via_private_t *dev_priv)
  97 {
  98         uint32_t agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
  99         uint32_t hw_addr = *(dev_priv->hw_addr_ptr) - agp_base;
 100
 101         return ((hw_addr <= dev_priv->dma_low) ?
 102                 (dev_priv->dma_low - hw_addr) :
 103                 (dev_priv->dma_wrap + dev_priv->dma_low - hw_addr));
 104 }
 105
 106 /*
 107  * Check that the given size fits in the buffer, otherwise wait.
 108  */
 109
 110 static inline int
 111 via_cmdbuf_wait(drm_via_private_t *dev_priv, unsigned int size)
 112 {
 113         uint32_t agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
 114         uint32_t cur_addr, hw_addr, next_addr;
 115         volatile uint32_t *hw_addr_ptr;
 116         uint32_t count;
 117         hw_addr_ptr = dev_priv->hw_addr_ptr;
 118         cur_addr = dev_priv->dma_low;
 119         next_addr = cur_addr + size + 512 * 1024;
 120         count = 1000000;
 121         do {
 122                 hw_addr = *hw_addr_ptr - agp_base;
 123                 if (count-- == 0) {
 124                         DRM_ERROR
 125                             ("via_cmdbuf_wait timed out hw %x cur_addr %x next_addr %x\n",
 126                              hw_addr, cur_addr, next_addr);
 127                         return -1;
 128                 }
 129                 if  ((cur_addr < hw_addr) && (next_addr >= hw_addr))
 130                         msleep(1);
 131         } while ((cur_addr < hw_addr) && (next_addr >= hw_addr));
 132         return 0;
 133 }
 134
 135 /*
 136  * Checks whether buffer head has reach the end. Rewind the ring buffer
 137  * when necessary.
 138  *
 139  * Returns virtual pointer to ring buffer.
 140  */
 141
 142 static inline uint32_t *via_check_dma(drm_via_private_t * dev_priv,
 143                                       unsigned int size)
 144 {
 145         if ((dev_priv->dma_low + size + 4 * CMDBUF_ALIGNMENT_SIZE) >
 146             dev_priv->dma_high) {
 147                 via_cmdbuf_rewind(dev_priv);
 148         }
 149         if (via_cmdbuf_wait(dev_priv, size) != 0)
 150                 return NULL;
 151
 152         return (uint32_t *) (dev_priv->dma_ptr + dev_priv->dma_low);
 153 }
 154
 155 int via_dma_cleanup(struct drm_device *dev)
 156 {
 157         if (dev->dev_private) {
 158                 drm_via_private_t *dev_priv =
 159                     (drm_via_private_t *) dev->dev_private;
 160
 161                 if (dev_priv->ring.virtual_start) {
 162                         via_cmdbuf_reset(dev_priv);
 163
 164                         drm_legacy_ioremapfree(&dev_priv->ring.map, dev);
 165                         dev_priv->ring.virtual_start = NULL;
 166                 }
 167
 168         }
 169
 170         return 0;
 171 }
 172
 173 static int via_initialize(struct drm_device *dev,
 174                           drm_via_private_t *dev_priv,
 175                           drm_via_dma_init_t *init)
 176 {
 177         if (!dev_priv || !dev_priv->mmio) {
 178                 DRM_ERROR("via_dma_init called before via_map_init\n");
 179                 return -EFAULT;
 180         }
 181
 182         if (dev_priv->ring.virtual_start != NULL) {
 183                 DRM_ERROR("called again without calling cleanup\n");
 184                 return -EFAULT;
 185         }
 186
 187         if (!dev->agp || !dev->agp->base) {
 188                 DRM_ERROR("called with no agp memory available\n");
 189                 return -EFAULT;
 190         }
 191
 192         if (dev_priv->chipset == VIA_DX9_0) {
 193                 DRM_ERROR("AGP DMA is not supported on this chip\n");
 194                 return -EINVAL;
 195         }
 196
 197         dev_priv->ring.map.offset = dev->agp->base + init->offset;
 198         dev_priv->ring.map.size = init->size;
 199         dev_priv->ring.map.type = 0;
 200         dev_priv->ring.map.flags = 0;
 201         dev_priv->ring.map.mtrr = 0;
 202
 203         drm_legacy_ioremap(&dev_priv->ring.map, dev);
 204
 205         if (dev_priv->ring.map.handle == NULL) {
 206                 via_dma_cleanup(dev);
 207                 DRM_ERROR("can not ioremap virtual address for"
 208                           " ring buffer\n");
 209                 return -ENOMEM;
 210         }
 211
 212         dev_priv->ring.virtual_start = dev_priv->ring.map.handle;
 213
 214         dev_priv->dma_ptr = dev_priv->ring.virtual_start;
 215         dev_priv->dma_low = 0;
 216         dev_priv->dma_high = init->size;
 217         dev_priv->dma_wrap = init->size;
 218         dev_priv->dma_offset = init->offset;
 219         dev_priv->last_pause_ptr = NULL;
 220         dev_priv->hw_addr_ptr =
 221                 (volatile uint32_t *)((char *)dev_priv->mmio->handle +
 222                 init->reg_pause_addr);
 223
 224         via_cmdbuf_start(dev_priv);
 225
 226         return 0;
 227 }
 228
 229 static int via_dma_init(struct drm_device *dev, void *data, struct drm_file *file_priv)
 230 {
 231         drm_via_private_t *dev_priv = (drm_via_private_t *) dev->dev_private;
 232         drm_via_dma_init_t *init = data;
 233         int retcode = 0;
 234
 235         switch (init->func) {
 236         case VIA_INIT_DMA:
 237                 if (!capable(CAP_SYS_ADMIN))
 238                         retcode = -EPERM;
 239                 else
 240                         retcode = via_initialize(dev, dev_priv, init);
 241                 break;
 242         case VIA_CLEANUP_DMA:
 243                 if (!capable(CAP_SYS_ADMIN))
 244                         retcode = -EPERM;
 245                 else
 246                         retcode = via_dma_cleanup(dev);
 247                 break;
 248         case VIA_DMA_INITIALIZED:
 249                 retcode = (dev_priv->ring.virtual_start != NULL) ?
 250                         0 : -EFAULT;
 251                 break;
 252         default:
 253                 retcode = -EINVAL;
 254                 break;
 255         }
 256
 257         return retcode;
 258 }
 259
 260 static int via_dispatch_cmdbuffer(struct drm_device *dev, drm_via_cmdbuffer_t *cmd)
 261 {
 262         drm_via_private_t *dev_priv;
 263         uint32_t *vb;
 264         int ret;
 265
 266         dev_priv = (drm_via_private_t *) dev->dev_private;
 267
 268         if (dev_priv->ring.virtual_start == NULL) {
 269                 DRM_ERROR("called without initializing AGP ring buffer.\n");
 270                 return -EFAULT;
 271         }
 272
 273         if (cmd->size > VIA_PCI_BUF_SIZE)
 274                 return -ENOMEM;
 275
 276         if (copy_from_user(dev_priv->pci_buf, cmd->buf, cmd->size))
 277                 return -EFAULT;
 278
 279         /*
 280          * Running this function on AGP memory is dead slow. Therefore
 281          * we run it on a temporary cacheable system memory buffer and
 282          * copy it to AGP memory when ready.
 283          */
 284
 285         if ((ret =
 286              via_verify_command_stream((uint32_t *) dev_priv->pci_buf,
 287                                        cmd->size, dev, 1))) {
 288                 return ret;
 289         }
 290
 291         vb = via_check_dma(dev_priv, (cmd->size < 0x100) ? 0x102 : cmd->size);
 292         if (vb == NULL)
 293                 return -EAGAIN;
 294
 295         memcpy(vb, dev_priv->pci_buf, cmd->size);
 296
 297         dev_priv->dma_low += cmd->size;
 298
 299         /*
 300          * Small submissions somehow stalls the CPU. (AGP cache effects?)
 301          * pad to greater size.
 302          */
 303
 304         if (cmd->size < 0x100)
 305                 via_pad_cache(dev_priv, (0x100 - cmd->size) >> 3);
 306         via_cmdbuf_pause(dev_priv);
 307
 308         return 0;
 309 }
 310
 311 int via_driver_dma_quiescent(struct drm_device *dev)
 312 {
 313         drm_via_private_t *dev_priv = dev->dev_private;
 314
 315         if (!via_wait_idle(dev_priv))
 316                 return -EBUSY;
 317         return 0;
 318 }
 319
 320 static int via_flush_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv)
 321 {
 322
 323         LOCK_TEST_WITH_RETURN(dev, file_priv);
 324
 325         return via_driver_dma_quiescent(dev);
 326 }
 327
 328 static int via_cmdbuffer(struct drm_device *dev, void *data, struct drm_file *file_priv)
 329 {
 330         drm_via_cmdbuffer_t *cmdbuf = data;
 331         int ret;
 332
 333         LOCK_TEST_WITH_RETURN(dev, file_priv);
 334
 335         DRM_DEBUG("buf %p size %lu\n", cmdbuf->buf, cmdbuf->size);
 336
 337         ret = via_dispatch_cmdbuffer(dev, cmdbuf);
 338         return ret;
 339 }
 340
 341 static int via_dispatch_pci_cmdbuffer(struct drm_device *dev,
 342                                       drm_via_cmdbuffer_t *cmd)
 343 {
 344         drm_via_private_t *dev_priv = dev->dev_private;
 345         int ret;
 346
 347         if (cmd->size > VIA_PCI_BUF_SIZE)
 348                 return -ENOMEM;
 349         if (copy_from_user(dev_priv->pci_buf, cmd->buf, cmd->size))
 350                 return -EFAULT;
 351
 352         if ((ret =
 353              via_verify_command_stream((uint32_t *) dev_priv->pci_buf,
 354                                        cmd->size, dev, 0))) {
 355                 return ret;
 356         }
 357
 358         ret =
 359             via_parse_command_stream(dev, (const uint32_t *)dev_priv->pci_buf,
 360                                      cmd->size);
 361         return ret;
 362 }
 363
 364 static int via_pci_cmdbuffer(struct drm_device *dev, void *data, struct drm_file *file_priv)
 365 {
 366         drm_via_cmdbuffer_t *cmdbuf = data;
 367         int ret;
 368
 369         LOCK_TEST_WITH_RETURN(dev, file_priv);
 370
 371         DRM_DEBUG("buf %p size %lu\n", cmdbuf->buf, cmdbuf->size);
 372
 373         ret = via_dispatch_pci_cmdbuffer(dev, cmdbuf);
 374         return ret;
 375 }
 376
 377 static inline uint32_t *via_align_buffer(drm_via_private_t *dev_priv,
 378                                          uint32_t * vb, int qw_count)
 379 {
 380         for (; qw_count > 0; --qw_count)
 381                 VIA_OUT_RING_QW(HC_DUMMY, HC_DUMMY);
 382         return vb;
 383 }
 384
 385 /*
 386  * This function is used internally by ring buffer management code.
 387  *
 388  * Returns virtual pointer to ring buffer.
 389  */
 390 static inline uint32_t *via_get_dma(drm_via_private_t *dev_priv)
 391 {
 392         return (uint32_t *) (dev_priv->dma_ptr + dev_priv->dma_low);
 393 }
 394
 395 /*
 396  * Hooks a segment of data into the tail of the ring-buffer by
 397  * modifying the pause address stored in the buffer itself. If
 398  * the regulator has already paused, restart it.
 399  */
 400 static int via_hook_segment(drm_via_private_t *dev_priv,
 401                             uint32_t pause_addr_hi, uint32_t pause_addr_lo,
 402                             int no_pci_fire)
 403 {
 404         int paused, count;
 405         volatile uint32_t *paused_at = dev_priv->last_pause_ptr;
 406         uint32_t reader, ptr;
 407         uint32_t diff;
 408
 409         paused = 0;
 410         via_flush_write_combine();
 411         (void) *(volatile uint32_t *)(via_get_dma(dev_priv) - 1);
 412
 413         *paused_at = pause_addr_lo;
 414         via_flush_write_combine();
 415         (void) *paused_at;
 416
 417         reader = *(dev_priv->hw_addr_ptr);
 418         ptr = ((volatile char *)paused_at - dev_priv->dma_ptr) +
 419                 dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr + 4;
 420
 421         dev_priv->last_pause_ptr = via_get_dma(dev_priv) - 1;
 422
 423         /*
 424          * If there is a possibility that the command reader will
 425          * miss the new pause address and pause on the old one,
 426          * In that case we need to program the new start address
 427          * using PCI.
 428          */
 429
 430         diff = (uint32_t) (ptr - reader) - dev_priv->dma_diff;
 431         count = 10000000;
 432         while (diff == 0 && count--) {
 433                 paused = (VIA_READ(0x41c) & 0x80000000);
 434                 if (paused)
 435                         break;
 436                 reader = *(dev_priv->hw_addr_ptr);
 437                 diff = (uint32_t) (ptr - reader) - dev_priv->dma_diff;
 438         }
 439
 440         paused = VIA_READ(0x41c) & 0x80000000;
 441
 442         if (paused && !no_pci_fire) {
 443                 reader = *(dev_priv->hw_addr_ptr);
 444                 diff = (uint32_t) (ptr - reader) - dev_priv->dma_diff;
 445                 diff &= (dev_priv->dma_high - 1);
 446                 if (diff != 0 && diff < (dev_priv->dma_high >> 1)) {
 447                         DRM_ERROR("Paused at incorrect address. "
 448                                   "0x%08x, 0x%08x 0x%08x\n",
 449                                   ptr, reader, dev_priv->dma_diff);
 450                 } else if (diff == 0) {
 451                         /*
 452                          * There is a concern that these writes may stall the PCI bus
 453                          * if the GPU is not idle. However, idling the GPU first
 454                          * doesn't make a difference.
 455                          */
 456
 457                         VIA_WRITE(VIA_REG_TRANSET, (HC_ParaType_PreCR << 16));
 458                         VIA_WRITE(VIA_REG_TRANSPACE, pause_addr_hi);
 459                         VIA_WRITE(VIA_REG_TRANSPACE, pause_addr_lo);
 460                         VIA_READ(VIA_REG_TRANSPACE);
 461                 }
 462         }
 463         return paused;
 464 }
 465
 466 static int via_wait_idle(drm_via_private_t *dev_priv)
 467 {
 468         int count = 10000000;
 469
 470         while (!(VIA_READ(VIA_REG_STATUS) & VIA_VR_QUEUE_BUSY) && --count)
 471                 ;
 472
 473         while (count && (VIA_READ(VIA_REG_STATUS) &
 474                            (VIA_CMD_RGTR_BUSY | VIA_2D_ENG_BUSY |
 475                             VIA_3D_ENG_BUSY)))
 476                 --count;
 477         return count;
 478 }
 479
 480 static uint32_t *via_align_cmd(drm_via_private_t *dev_priv, uint32_t cmd_type,
 481                                uint32_t addr, uint32_t *cmd_addr_hi,
 482                                uint32_t *cmd_addr_lo, int skip_wait)
 483 {
 484         uint32_t agp_base;
 485         uint32_t cmd_addr, addr_lo, addr_hi;
 486         uint32_t *vb;
 487         uint32_t qw_pad_count;
 488
 489         if (!skip_wait)
 490                 via_cmdbuf_wait(dev_priv, 2 * CMDBUF_ALIGNMENT_SIZE);
 491
 492         vb = via_get_dma(dev_priv);
 493         VIA_OUT_RING_QW(HC_HEADER2 | ((VIA_REG_TRANSET >> 2) << 12) |
 494                         (VIA_REG_TRANSPACE >> 2), HC_ParaType_PreCR << 16);
 495         agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
 496         qw_pad_count = (CMDBUF_ALIGNMENT_SIZE >> 3) -
 497             ((dev_priv->dma_low & CMDBUF_ALIGNMENT_MASK) >> 3);
 498
 499         cmd_addr = (addr) ? addr :
 500             agp_base + dev_priv->dma_low - 8 + (qw_pad_count << 3);
 501         addr_lo = ((HC_SubA_HAGPBpL << 24) | (cmd_type & HC_HAGPBpID_MASK) |
 502                    (cmd_addr & HC_HAGPBpL_MASK));
 503         addr_hi = ((HC_SubA_HAGPBpH << 24) | (cmd_addr >> 24));
 504
 505         vb = via_align_buffer(dev_priv, vb, qw_pad_count - 1);
 506         VIA_OUT_RING_QW(*cmd_addr_hi = addr_hi, *cmd_addr_lo = addr_lo);
 507         return vb;
 508 }
 509
 510 static void via_cmdbuf_start(drm_via_private_t *dev_priv)
 511 {
 512         uint32_t pause_addr_lo, pause_addr_hi;
 513         uint32_t start_addr, start_addr_lo;
 514         uint32_t end_addr, end_addr_lo;
 515         uint32_t command;
 516         uint32_t agp_base;
 517         uint32_t ptr;
 518         uint32_t reader;
 519         int count;
 520
 521         dev_priv->dma_low = 0;
 522
 523         agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
 524         start_addr = agp_base;
 525         end_addr = agp_base + dev_priv->dma_high;
 526
 527         start_addr_lo = ((HC_SubA_HAGPBstL << 24) | (start_addr & 0xFFFFFF));
 528         end_addr_lo = ((HC_SubA_HAGPBendL << 24) | (end_addr & 0xFFFFFF));
 529         command = ((HC_SubA_HAGPCMNT << 24) | (start_addr >> 24) |
 530                    ((end_addr & 0xff000000) >> 16));
 531
 532         dev_priv->last_pause_ptr =
 533             via_align_cmd(dev_priv, HC_HAGPBpID_PAUSE, 0,
 534                           &pause_addr_hi, &pause_addr_lo, 1) - 1;
 535
 536         via_flush_write_combine();
 537         (void) *(volatile uint32_t *)dev_priv->last_pause_ptr;
 538
 539         VIA_WRITE(VIA_REG_TRANSET, (HC_ParaType_PreCR << 16));
 540         VIA_WRITE(VIA_REG_TRANSPACE, command);
 541         VIA_WRITE(VIA_REG_TRANSPACE, start_addr_lo);
 542         VIA_WRITE(VIA_REG_TRANSPACE, end_addr_lo);
 543
 544         VIA_WRITE(VIA_REG_TRANSPACE, pause_addr_hi);
 545         VIA_WRITE(VIA_REG_TRANSPACE, pause_addr_lo);
 546         wmb();
 547         VIA_WRITE(VIA_REG_TRANSPACE, command | HC_HAGPCMNT_MASK);
 548         VIA_READ(VIA_REG_TRANSPACE);
 549
 550         dev_priv->dma_diff = 0;
 551
 552         count = 10000000;
 553         while (!(VIA_READ(0x41c) & 0x80000000) && count--);
 554
 555         reader = *(dev_priv->hw_addr_ptr);
 556         ptr = ((volatile char *)dev_priv->last_pause_ptr - dev_priv->dma_ptr) +
 557             dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr + 4;
 558
 559         /*
 560          * This is the difference between where we tell the
 561          * command reader to pause and where it actually pauses.
 562          * This differs between hw implementation so we need to
 563          * detect it.
 564          */
 565
 566         dev_priv->dma_diff = ptr - reader;
 567 }
 568
 569 static void via_pad_cache(drm_via_private_t *dev_priv, int qwords)
 570 {
 571         uint32_t *vb;
 572
 573         via_cmdbuf_wait(dev_priv, qwords + 2);
 574         vb = via_get_dma(dev_priv);
 575         VIA_OUT_RING_QW(HC_HEADER2, HC_ParaType_NotTex << 16);
 576         via_align_buffer(dev_priv, vb, qwords);
 577 }
 578
 579 static inline void via_dummy_bitblt(drm_via_private_t *dev_priv)
 580 {
 581         uint32_t *vb = via_get_dma(dev_priv);
 582         SetReg2DAGP(0x0C, (0 | (0 << 16)));
 583         SetReg2DAGP(0x10, 0 | (0 << 16));
 584         SetReg2DAGP(0x0, 0x1 | 0x2000 | 0xAA000000);
 585 }
 586
 587 static void via_cmdbuf_jump(drm_via_private_t *dev_priv)
 588 {
 589         uint32_t agp_base;
 590         uint32_t pause_addr_lo, pause_addr_hi;
 591         uint32_t jump_addr_lo, jump_addr_hi;
 592         volatile uint32_t *last_pause_ptr;
 593         uint32_t dma_low_save1, dma_low_save2;
 594
 595         agp_base = dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr;
 596         via_align_cmd(dev_priv, HC_HAGPBpID_JUMP, 0, &jump_addr_hi,
 597                       &jump_addr_lo, 0);
 598
 599         dev_priv->dma_wrap = dev_priv->dma_low;
 600
 601         /*
 602          * Wrap command buffer to the beginning.
 603          */
 604
 605         dev_priv->dma_low = 0;
 606         if (via_cmdbuf_wait(dev_priv, CMDBUF_ALIGNMENT_SIZE) != 0)
 607                 DRM_ERROR("via_cmdbuf_jump failed\n");
 608
 609         via_dummy_bitblt(dev_priv);
 610         via_dummy_bitblt(dev_priv);
 611
 612         last_pause_ptr =
 613             via_align_cmd(dev_priv, HC_HAGPBpID_PAUSE, 0, &pause_addr_hi,
 614                           &pause_addr_lo, 0) - 1;
 615         via_align_cmd(dev_priv, HC_HAGPBpID_PAUSE, 0, &pause_addr_hi,
 616                       &pause_addr_lo, 0);
 617
 618         *last_pause_ptr = pause_addr_lo;
 619         dma_low_save1 = dev_priv->dma_low;
 620
 621         /*
 622          * Now, set a trap that will pause the regulator if it tries to rerun the old
 623          * command buffer. (Which may happen if via_hook_segment detecs a command regulator pause
 624          * and reissues the jump command over PCI, while the regulator has already taken the jump
 625          * and actually paused at the current buffer end).
 626          * There appears to be no other way to detect this condition, since the hw_addr_pointer
 627          * does not seem to get updated immediately when a jump occurs.
 628          */
 629
 630         last_pause_ptr =
 631                 via_align_cmd(dev_priv, HC_HAGPBpID_PAUSE, 0, &pause_addr_hi,
 632                               &pause_addr_lo, 0) - 1;
 633         via_align_cmd(dev_priv, HC_HAGPBpID_PAUSE, 0, &pause_addr_hi,
 634                       &pause_addr_lo, 0);
 635         *last_pause_ptr = pause_addr_lo;
 636
 637         dma_low_save2 = dev_priv->dma_low;
 638         dev_priv->dma_low = dma_low_save1;
 639         via_hook_segment(dev_priv, jump_addr_hi, jump_addr_lo, 0);
 640         dev_priv->dma_low = dma_low_save2;
 641         via_hook_segment(dev_priv, pause_addr_hi, pause_addr_lo, 0);
 642 }
 643
 644
 645 static void via_cmdbuf_rewind(drm_via_private_t *dev_priv)
 646 {
 647         via_cmdbuf_jump(dev_priv);
 648 }
 649
 650 static void via_cmdbuf_flush(drm_via_private_t *dev_priv, uint32_t cmd_type)
 651 {
 652         uint32_t pause_addr_lo, pause_addr_hi;
 653
 654         via_align_cmd(dev_priv, cmd_type, 0, &pause_addr_hi, &pause_addr_lo, 0);
 655         via_hook_segment(dev_priv, pause_addr_hi, pause_addr_lo, 0);
 656 }
 657
 658 static void via_cmdbuf_pause(drm_via_private_t *dev_priv)
 659 {
 660         via_cmdbuf_flush(dev_priv, HC_HAGPBpID_PAUSE);
 661 }
 662
 663 static void via_cmdbuf_reset(drm_via_private_t *dev_priv)
 664 {
 665         via_cmdbuf_flush(dev_priv, HC_HAGPBpID_STOP);
 666         via_wait_idle(dev_priv);
 667 }
 668
 669 /*
 670  * User interface to the space and lag functions.
 671  */
 672
 673 static int via_cmdbuf_size(struct drm_device *dev, void *data, struct drm_file *file_priv)
 674 {
 675         drm_via_cmdbuf_size_t *d_siz = data;
 676         int ret = 0;
 677         uint32_t tmp_size, count;
 678         drm_via_private_t *dev_priv;
 679
 680         DRM_DEBUG("\n");
 681         LOCK_TEST_WITH_RETURN(dev, file_priv);
 682
 683         dev_priv = (drm_via_private_t *) dev->dev_private;
 684
 685         if (dev_priv->ring.virtual_start == NULL) {
 686                 DRM_ERROR("called without initializing AGP ring buffer.\n");
 687                 return -EFAULT;
 688         }
 689
 690         count = 1000000;
 691         tmp_size = d_siz->size;
 692         switch (d_siz->func) {
 693         case VIA_CMDBUF_SPACE:
 694                 while (((tmp_size = via_cmdbuf_space(dev_priv)) < d_siz->size)
 695                        && --count) {
 696                         if (!d_siz->wait)
 697                                 break;
 698                 }
 699                 if (!count) {
 700                         DRM_ERROR("VIA_CMDBUF_SPACE timed out.\n");
 701                         ret = -EAGAIN;
 702                 }
 703                 break;
 704         case VIA_CMDBUF_LAG:
 705                 while (((tmp_size = via_cmdbuf_lag(dev_priv)) > d_siz->size)
 706                        && --count) {
 707                         if (!d_siz->wait)
 708                                 break;
 709                 }
 710                 if (!count) {
 711                         DRM_ERROR("VIA_CMDBUF_LAG timed out.\n");
 712                         ret = -EAGAIN;
 713                 }
 714                 break;
 715         default:
 716                 ret = -EFAULT;
 717         }
 718         d_siz->size = tmp_size;
 719
 720         return ret;
 721 }
 722
 723 const struct drm_ioctl_desc via_ioctls[] = {
 724         DRM_IOCTL_DEF_DRV(VIA_ALLOCMEM, via_mem_alloc, DRM_AUTH),
 725         DRM_IOCTL_DEF_DRV(VIA_FREEMEM, via_mem_free, DRM_AUTH),
 726         DRM_IOCTL_DEF_DRV(VIA_AGP_INIT, via_agp_init, DRM_AUTH|DRM_MASTER),
 727         DRM_IOCTL_DEF_DRV(VIA_FB_INIT, via_fb_init, DRM_AUTH|DRM_MASTER),
 728         DRM_IOCTL_DEF_DRV(VIA_MAP_INIT, via_map_init, DRM_AUTH|DRM_MASTER),
 729         DRM_IOCTL_DEF_DRV(VIA_DEC_FUTEX, via_decoder_futex, DRM_AUTH),
 730         DRM_IOCTL_DEF_DRV(VIA_DMA_INIT, via_dma_init, DRM_AUTH),
 731         DRM_IOCTL_DEF_DRV(VIA_CMDBUFFER, via_cmdbuffer, DRM_AUTH),
 732         DRM_IOCTL_DEF_DRV(VIA_FLUSH, via_flush_ioctl, DRM_AUTH),
 733         DRM_IOCTL_DEF_DRV(VIA_PCICMD, via_pci_cmdbuffer, DRM_AUTH),
 734         DRM_IOCTL_DEF_DRV(VIA_CMDBUF_SIZE, via_cmdbuf_size, DRM_AUTH),
 735         DRM_IOCTL_DEF_DRV(VIA_WAIT_IRQ, via_wait_irq, DRM_AUTH),
 736         DRM_IOCTL_DEF_DRV(VIA_DMA_BLIT, via_dma_blit, DRM_AUTH),
 737         DRM_IOCTL_DEF_DRV(VIA_BLIT_SYNC, via_dma_blit_sync, DRM_AUTH)
 738 };
 739
 740 int via_max_ioctl = ARRAY_SIZE(via_ioctls);