drivers/gpu/drm/i915/i915_sysfs.c

   1 /*
   2  * Copyright © 2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Ben Widawsky <ben@bwidawsk.net>
  25  *
  26  */
  27
  28 #include <linux/device.h>
  29 #include <linux/module.h>
  30 #include <linux/stat.h>
  31 #include <linux/sysfs.h>
  32 #include "intel_drv.h"
  33 #include "i915_drv.h"
  34
  35 #define dev_to_drm_minor(d) dev_get_drvdata((d))
  36
  37 #ifdef CONFIG_PM
  38 static u32 calc_residency(struct drm_device *dev, const u32 reg)
  39 {
  40         struct drm_i915_private *dev_priv = dev->dev_private;
  41         u64 raw_time; /* 32b value may overflow during fixed point math */
  42         u64 units = 128ULL, div = 100000ULL, bias = 100ULL;
  43         u32 ret;
  44
  45         if (!intel_enable_rc6(dev))
  46                 return 0;
  47
  48         intel_runtime_pm_get(dev_priv);
  49
  50         /* On VLV and CHV, residency time is in CZ units rather than 1.28us */
  51         if (IS_VALLEYVIEW(dev)) {
  52                 u32 reg, czcount_30ns;
  53
  54                 if (IS_CHERRYVIEW(dev))
  55                         reg = CHV_CLK_CTL1;
  56                 else
  57                         reg = VLV_CLK_CTL2;
  58
  59                 czcount_30ns = I915_READ(reg) >> CLK_CTL2_CZCOUNT_30NS_SHIFT;
  60
  61                 if (!czcount_30ns) {
  62                         WARN(!czcount_30ns, "bogus CZ count value");
  63                         ret = 0;
  64                         goto out;
  65                 }
  66
  67                 units = 0;
  68                 div = 1000000ULL;
  69
  70                 if (IS_CHERRYVIEW(dev)) {
  71                         /* Special case for 320Mhz */
  72                         if (czcount_30ns == 1) {
  73                                 div = 10000000ULL;
  74                                 units = 3125ULL;
  75                         } else {
  76                                 /* chv counts are one less */
  77                                 czcount_30ns += 1;
  78                         }
  79                 }
  80
  81                 if (units == 0)
  82                         units = DIV_ROUND_UP_ULL(30ULL * bias,
  83                                                  (u64)czcount_30ns);
  84
  85                 if (I915_READ(VLV_COUNTER_CONTROL) & VLV_COUNT_RANGE_HIGH)
  86                         units <<= 8;
  87
  88                 div = div * bias;
  89         }
  90
  91         raw_time = I915_READ(reg) * units;
  92         ret = DIV_ROUND_UP_ULL(raw_time, div);
  93
  94 out:
  95         intel_runtime_pm_put(dev_priv);
  96         return ret;
  97 }
  98
  99 static ssize_t
 100 show_rc6_mask(struct device *kdev, struct device_attribute *attr, char *buf)
 101 {
 102         struct drm_minor *dminor = dev_to_drm_minor(kdev);
 103         return snprintf(buf, PAGE_SIZE, "%x\n", intel_enable_rc6(dminor->dev));
 104 }
 105
 106 static ssize_t
 107 show_rc6_ms(struct device *kdev, struct device_attribute *attr, char *buf)
 108 {
 109         struct drm_minor *dminor = dev_get_drvdata(kdev);
 110         u32 rc6_residency = calc_residency(dminor->dev, GEN6_GT_GFX_RC6);
 111         return snprintf(buf, PAGE_SIZE, "%u\n", rc6_residency);
 112 }
 113
 114 static ssize_t
 115 show_rc6p_ms(struct device *kdev, struct device_attribute *attr, char *buf)
 116 {
 117         struct drm_minor *dminor = dev_to_drm_minor(kdev);
 118         u32 rc6p_residency = calc_residency(dminor->dev, GEN6_GT_GFX_RC6p);
 119         if (IS_VALLEYVIEW(dminor->dev))
 120                 rc6p_residency = 0;
 121         return snprintf(buf, PAGE_SIZE, "%u\n", rc6p_residency);
 122 }
 123
 124 static ssize_t
 125 show_rc6pp_ms(struct device *kdev, struct device_attribute *attr, char *buf)
 126 {
 127         struct drm_minor *dminor = dev_to_drm_minor(kdev);
 128         u32 rc6pp_residency = calc_residency(dminor->dev, GEN6_GT_GFX_RC6pp);
 129         if (IS_VALLEYVIEW(dminor->dev))
 130                 rc6pp_residency = 0;
 131         return snprintf(buf, PAGE_SIZE, "%u\n", rc6pp_residency);
 132 }
 133
 134 static DEVICE_ATTR(rc6_enable, S_IRUGO, show_rc6_mask, NULL);
 135 static DEVICE_ATTR(rc6_residency_ms, S_IRUGO, show_rc6_ms, NULL);
 136 static DEVICE_ATTR(rc6p_residency_ms, S_IRUGO, show_rc6p_ms, NULL);
 137 static DEVICE_ATTR(rc6pp_residency_ms, S_IRUGO, show_rc6pp_ms, NULL);
 138
 139 static struct attribute *rc6_attrs[] = {
 140         &dev_attr_rc6_enable.attr,
 141         &dev_attr_rc6_residency_ms.attr,
 142         NULL
 143 };
 144
 145 static struct attribute_group rc6_attr_group = {
 146         .name = power_group_name,
 147         .attrs =  rc6_attrs
 148 };
 149
 150 static struct attribute *rc6p_attrs[] = {
 151         &dev_attr_rc6p_residency_ms.attr,
 152         &dev_attr_rc6pp_residency_ms.attr,
 153         NULL
 154 };
 155
 156 static struct attribute_group rc6p_attr_group = {
 157         .name = power_group_name,
 158         .attrs =  rc6p_attrs
 159 };
 160 #endif
 161
 162 static int l3_access_valid(struct drm_device *dev, loff_t offset)
 163 {
 164         if (!HAS_L3_DPF(dev))
 165                 return -EPERM;
 166
 167         if (offset % 4 != 0)
 168                 return -EINVAL;
 169
 170         if (offset >= GEN7_L3LOG_SIZE)
 171                 return -ENXIO;
 172
 173         return 0;
 174 }
 175
 176 static ssize_t
 177 i915_l3_read(struct file *filp, struct kobject *kobj,
 178              struct bin_attribute *attr, char *buf,
 179              loff_t offset, size_t count)
 180 {
 181         struct device *dev = container_of(kobj, struct device, kobj);
 182         struct drm_minor *dminor = dev_to_drm_minor(dev);
 183         struct drm_device *drm_dev = dminor->dev;
 184         struct drm_i915_private *dev_priv = drm_dev->dev_private;
 185         int slice = (int)(uintptr_t)attr->private;
 186         int ret;
 187
 188         count = round_down(count, 4);
 189
 190         ret = l3_access_valid(drm_dev, offset);
 191         if (ret)
 192                 return ret;
 193
 194         count = min_t(size_t, GEN7_L3LOG_SIZE - offset, count);
 195
 196         ret = i915_mutex_lock_interruptible(drm_dev);
 197         if (ret)
 198                 return ret;
 199
 200         if (dev_priv->l3_parity.remap_info[slice])
 201                 memcpy(buf,
 202                        dev_priv->l3_parity.remap_info[slice] + (offset/4),
 203                        count);
 204         else
 205                 memset(buf, 0, count);
 206
 207         mutex_unlock(&drm_dev->struct_mutex);
 208
 209         return count;
 210 }
 211
 212 static ssize_t
 213 i915_l3_write(struct file *filp, struct kobject *kobj,
 214               struct bin_attribute *attr, char *buf,
 215               loff_t offset, size_t count)
 216 {
 217         struct device *dev = container_of(kobj, struct device, kobj);
 218         struct drm_minor *dminor = dev_to_drm_minor(dev);
 219         struct drm_device *drm_dev = dminor->dev;
 220         struct drm_i915_private *dev_priv = drm_dev->dev_private;
 221         struct intel_context *ctx;
 222         u32 *temp = NULL; /* Just here to make handling failures easy */
 223         int slice = (int)(uintptr_t)attr->private;
 224         int ret;
 225
 226         if (!HAS_HW_CONTEXTS(drm_dev))
 227                 return -ENXIO;
 228
 229         ret = l3_access_valid(drm_dev, offset);
 230         if (ret)
 231                 return ret;
 232
 233         ret = i915_mutex_lock_interruptible(drm_dev);
 234         if (ret)
 235                 return ret;
 236
 237         if (!dev_priv->l3_parity.remap_info[slice]) {
 238                 temp = kzalloc(GEN7_L3LOG_SIZE, GFP_KERNEL);
 239                 if (!temp) {
 240                         mutex_unlock(&drm_dev->struct_mutex);
 241                         return -ENOMEM;
 242                 }
 243         }
 244
 245         ret = i915_gpu_idle(drm_dev);
 246         if (ret) {
 247                 kfree(temp);
 248                 mutex_unlock(&drm_dev->struct_mutex);
 249                 return ret;
 250         }
 251
 252         /* TODO: Ideally we really want a GPU reset here to make sure errors
 253          * aren't propagated. Since I cannot find a stable way to reset the GPU
 254          * at this point it is left as a TODO.
 255         */
 256         if (temp)
 257                 dev_priv->l3_parity.remap_info[slice] = temp;
 258
 259         memcpy(dev_priv->l3_parity.remap_info[slice] + (offset/4), buf, count);
 260
 261         /* NB: We defer the remapping until we switch to the context */
 262         list_for_each_entry(ctx, &dev_priv->context_list, link)
 263                 ctx->remap_slice |= (1<<slice);
 264
 265         mutex_unlock(&drm_dev->struct_mutex);
 266
 267         return count;
 268 }
 269
 270 static struct bin_attribute dpf_attrs = {
 271         .attr = {.name = "l3_parity", .mode = (S_IRUSR | S_IWUSR)},
 272         .size = GEN7_L3LOG_SIZE,
 273         .read = i915_l3_read,
 274         .write = i915_l3_write,
 275         .mmap = NULL,
 276         .private = (void *)0
 277 };
 278
 279 static struct bin_attribute dpf_attrs_1 = {
 280         .attr = {.name = "l3_parity_slice_1", .mode = (S_IRUSR | S_IWUSR)},
 281         .size = GEN7_L3LOG_SIZE,
 282         .read = i915_l3_read,
 283         .write = i915_l3_write,
 284         .mmap = NULL,
 285         .private = (void *)1
 286 };
 287
 288 static ssize_t gt_cur_freq_mhz_show(struct device *kdev,
 289                                     struct device_attribute *attr, char *buf)
 290 {
 291         struct drm_minor *minor = dev_to_drm_minor(kdev);
 292         struct drm_device *dev = minor->dev;
 293         struct drm_i915_private *dev_priv = dev->dev_private;
 294         int ret;
 295
 296         flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 297
 298         intel_runtime_pm_get(dev_priv);
 299
 300         mutex_lock(&dev_priv->rps.hw_lock);
 301         if (IS_VALLEYVIEW(dev_priv->dev)) {
 302                 u32 freq;
 303                 freq = vlv_punit_read(dev_priv, PUNIT_REG_GPU_FREQ_STS);
 304                 ret = vlv_gpu_freq(dev_priv, (freq >> 8) & 0xff);
 305         } else {
 306                 ret = dev_priv->rps.cur_freq * GT_FREQUENCY_MULTIPLIER;
 307         }
 308         mutex_unlock(&dev_priv->rps.hw_lock);
 309
 310         intel_runtime_pm_put(dev_priv);
 311
 312         return snprintf(buf, PAGE_SIZE, "%d\n", ret);
 313 }
 314
 315 static ssize_t vlv_rpe_freq_mhz_show(struct device *kdev,
 316                                      struct device_attribute *attr, char *buf)
 317 {
 318         struct drm_minor *minor = dev_to_drm_minor(kdev);
 319         struct drm_device *dev = minor->dev;
 320         struct drm_i915_private *dev_priv = dev->dev_private;
 321
 322         return snprintf(buf, PAGE_SIZE, "%d\n",
 323                         vlv_gpu_freq(dev_priv, dev_priv->rps.efficient_freq));
 324 }
 325
 326 static ssize_t gt_max_freq_mhz_show(struct device *kdev, struct device_attribute *attr, char *buf)
 327 {
 328         struct drm_minor *minor = dev_to_drm_minor(kdev);
 329         struct drm_device *dev = minor->dev;
 330         struct drm_i915_private *dev_priv = dev->dev_private;
 331         int ret;
 332
 333         flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 334
 335         mutex_lock(&dev_priv->rps.hw_lock);
 336         if (IS_VALLEYVIEW(dev_priv->dev))
 337                 ret = vlv_gpu_freq(dev_priv, dev_priv->rps.max_freq_softlimit);
 338         else
 339                 ret = dev_priv->rps.max_freq_softlimit * GT_FREQUENCY_MULTIPLIER;
 340         mutex_unlock(&dev_priv->rps.hw_lock);
 341
 342         return snprintf(buf, PAGE_SIZE, "%d\n", ret);
 343 }
 344
 345 static ssize_t gt_max_freq_mhz_store(struct device *kdev,
 346                                      struct device_attribute *attr,
 347                                      const char *buf, size_t count)
 348 {
 349         struct drm_minor *minor = dev_to_drm_minor(kdev);
 350         struct drm_device *dev = minor->dev;
 351         struct drm_i915_private *dev_priv = dev->dev_private;
 352         u32 val;
 353         ssize_t ret;
 354
 355         ret = kstrtou32(buf, 0, &val);
 356         if (ret)
 357                 return ret;
 358
 359         flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 360
 361         mutex_lock(&dev_priv->rps.hw_lock);
 362
 363         if (IS_VALLEYVIEW(dev_priv->dev))
 364                 val = vlv_freq_opcode(dev_priv, val);
 365         else
 366                 val /= GT_FREQUENCY_MULTIPLIER;
 367
 368         if (val < dev_priv->rps.min_freq ||
 369             val > dev_priv->rps.max_freq ||
 370             val < dev_priv->rps.min_freq_softlimit) {
 371                 mutex_unlock(&dev_priv->rps.hw_lock);
 372                 return -EINVAL;
 373         }
 374
 375         if (val > dev_priv->rps.rp0_freq)
 376                 DRM_DEBUG("User requested overclocking to %d\n",
 377                           val * GT_FREQUENCY_MULTIPLIER);
 378
 379         dev_priv->rps.max_freq_softlimit = val;
 380
 381         if (dev_priv->rps.cur_freq > val) {
 382                 if (IS_VALLEYVIEW(dev))
 383                         valleyview_set_rps(dev, val);
 384                 else
 385                         gen6_set_rps(dev, val);
 386         } else if (!IS_VALLEYVIEW(dev)) {
 387                 /* We still need gen6_set_rps to process the new max_delay and
 388                  * update the interrupt limits even though frequency request is
 389                  * unchanged. */
 390                 gen6_set_rps(dev, dev_priv->rps.cur_freq);
 391         }
 392
 393         mutex_unlock(&dev_priv->rps.hw_lock);
 394
 395         return count;
 396 }
 397
 398 static ssize_t gt_min_freq_mhz_show(struct device *kdev, struct device_attribute *attr, char *buf)
 399 {
 400         struct drm_minor *minor = dev_to_drm_minor(kdev);
 401         struct drm_device *dev = minor->dev;
 402         struct drm_i915_private *dev_priv = dev->dev_private;
 403         int ret;
 404
 405         flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 406
 407         mutex_lock(&dev_priv->rps.hw_lock);
 408         if (IS_VALLEYVIEW(dev_priv->dev))
 409                 ret = vlv_gpu_freq(dev_priv, dev_priv->rps.min_freq_softlimit);
 410         else
 411                 ret = dev_priv->rps.min_freq_softlimit * GT_FREQUENCY_MULTIPLIER;
 412         mutex_unlock(&dev_priv->rps.hw_lock);
 413
 414         return snprintf(buf, PAGE_SIZE, "%d\n", ret);
 415 }
 416
 417 static ssize_t gt_min_freq_mhz_store(struct device *kdev,
 418                                      struct device_attribute *attr,
 419                                      const char *buf, size_t count)
 420 {
 421         struct drm_minor *minor = dev_to_drm_minor(kdev);
 422         struct drm_device *dev = minor->dev;
 423         struct drm_i915_private *dev_priv = dev->dev_private;
 424         u32 val;
 425         ssize_t ret;
 426
 427         ret = kstrtou32(buf, 0, &val);
 428         if (ret)
 429                 return ret;
 430
 431         flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 432
 433         mutex_lock(&dev_priv->rps.hw_lock);
 434
 435         if (IS_VALLEYVIEW(dev))
 436                 val = vlv_freq_opcode(dev_priv, val);
 437         else
 438                 val /= GT_FREQUENCY_MULTIPLIER;
 439
 440         if (val < dev_priv->rps.min_freq ||
 441             val > dev_priv->rps.max_freq ||
 442             val > dev_priv->rps.max_freq_softlimit) {
 443                 mutex_unlock(&dev_priv->rps.hw_lock);
 444                 return -EINVAL;
 445         }
 446
 447         dev_priv->rps.min_freq_softlimit = val;
 448
 449         if (dev_priv->rps.cur_freq < val) {
 450                 if (IS_VALLEYVIEW(dev))
 451                         valleyview_set_rps(dev, val);
 452                 else
 453                         gen6_set_rps(dev, val);
 454         } else if (!IS_VALLEYVIEW(dev)) {
 455                 /* We still need gen6_set_rps to process the new min_delay and
 456                  * update the interrupt limits even though frequency request is
 457                  * unchanged. */
 458                 gen6_set_rps(dev, dev_priv->rps.cur_freq);
 459         }
 460
 461         mutex_unlock(&dev_priv->rps.hw_lock);
 462
 463         return count;
 464
 465 }
 466
 467 static DEVICE_ATTR(gt_cur_freq_mhz, S_IRUGO, gt_cur_freq_mhz_show, NULL);
 468 static DEVICE_ATTR(gt_max_freq_mhz, S_IRUGO | S_IWUSR, gt_max_freq_mhz_show, gt_max_freq_mhz_store);
 469 static DEVICE_ATTR(gt_min_freq_mhz, S_IRUGO | S_IWUSR, gt_min_freq_mhz_show, gt_min_freq_mhz_store);
 470
 471 static DEVICE_ATTR(vlv_rpe_freq_mhz, S_IRUGO, vlv_rpe_freq_mhz_show, NULL);
 472
 473 static ssize_t gt_rp_mhz_show(struct device *kdev, struct device_attribute *attr, char *buf);
 474 static DEVICE_ATTR(gt_RP0_freq_mhz, S_IRUGO, gt_rp_mhz_show, NULL);
 475 static DEVICE_ATTR(gt_RP1_freq_mhz, S_IRUGO, gt_rp_mhz_show, NULL);
 476 static DEVICE_ATTR(gt_RPn_freq_mhz, S_IRUGO, gt_rp_mhz_show, NULL);
 477
 478 /* For now we have a static number of RP states */
 479 static ssize_t gt_rp_mhz_show(struct device *kdev, struct device_attribute *attr, char *buf)
 480 {
 481         struct drm_minor *minor = dev_to_drm_minor(kdev);
 482         struct drm_device *dev = minor->dev;
 483         struct drm_i915_private *dev_priv = dev->dev_private;
 484         u32 val, rp_state_cap;
 485         ssize_t ret;
 486
 487         ret = mutex_lock_interruptible(&dev->struct_mutex);
 488         if (ret)
 489                 return ret;
 490         intel_runtime_pm_get(dev_priv);
 491         rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
 492         intel_runtime_pm_put(dev_priv);
 493         mutex_unlock(&dev->struct_mutex);
 494
 495         if (attr == &dev_attr_gt_RP0_freq_mhz) {
 496                 if (IS_VALLEYVIEW(dev))
 497                         val = vlv_gpu_freq(dev_priv, dev_priv->rps.rp0_freq);
 498                 else
 499                         val = ((rp_state_cap & 0x0000ff) >> 0) * GT_FREQUENCY_MULTIPLIER;
 500         } else if (attr == &dev_attr_gt_RP1_freq_mhz) {
 501                 if (IS_VALLEYVIEW(dev))
 502                         val = vlv_gpu_freq(dev_priv, dev_priv->rps.rp1_freq);
 503                 else
 504                         val = ((rp_state_cap & 0x00ff00) >> 8) * GT_FREQUENCY_MULTIPLIER;
 505         } else if (attr == &dev_attr_gt_RPn_freq_mhz) {
 506                 if (IS_VALLEYVIEW(dev))
 507                         val = vlv_gpu_freq(dev_priv, dev_priv->rps.min_freq);
 508                 else
 509                         val = ((rp_state_cap & 0xff0000) >> 16) * GT_FREQUENCY_MULTIPLIER;
 510         } else {
 511                 BUG();
 512         }
 513         return snprintf(buf, PAGE_SIZE, "%d\n", val);
 514 }
 515
 516 static const struct attribute *gen6_attrs[] = {
 517         &dev_attr_gt_cur_freq_mhz.attr,
 518         &dev_attr_gt_max_freq_mhz.attr,
 519         &dev_attr_gt_min_freq_mhz.attr,
 520         &dev_attr_gt_RP0_freq_mhz.attr,
 521         &dev_attr_gt_RP1_freq_mhz.attr,
 522         &dev_attr_gt_RPn_freq_mhz.attr,
 523         NULL,
 524 };
 525
 526 static const struct attribute *vlv_attrs[] = {
 527         &dev_attr_gt_cur_freq_mhz.attr,
 528         &dev_attr_gt_max_freq_mhz.attr,
 529         &dev_attr_gt_min_freq_mhz.attr,
 530         &dev_attr_gt_RP0_freq_mhz.attr,
 531         &dev_attr_gt_RP1_freq_mhz.attr,
 532         &dev_attr_gt_RPn_freq_mhz.attr,
 533         &dev_attr_vlv_rpe_freq_mhz.attr,
 534         NULL,
 535 };
 536
 537 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
 538                                 struct bin_attribute *attr, char *buf,
 539                                 loff_t off, size_t count)
 540 {
 541
 542         struct device *kdev = container_of(kobj, struct device, kobj);
 543         struct drm_minor *minor = dev_to_drm_minor(kdev);
 544         struct drm_device *dev = minor->dev;
 545         struct i915_error_state_file_priv error_priv;
 546         struct drm_i915_error_state_buf error_str;
 547         ssize_t ret_count = 0;
 548         int ret;
 549
 550         memset(&error_priv, 0, sizeof(error_priv));
 551
 552         ret = i915_error_state_buf_init(&error_str, to_i915(dev), count, off);
 553         if (ret)
 554                 return ret;
 555
 556         error_priv.dev = dev;
 557         i915_error_state_get(dev, &error_priv);
 558
 559         ret = i915_error_state_to_str(&error_str, &error_priv);
 560         if (ret)
 561                 goto out;
 562
 563         ret_count = count < error_str.bytes ? count : error_str.bytes;
 564
 565         memcpy(buf, error_str.buf, ret_count);
 566 out:
 567         i915_error_state_put(&error_priv);
 568         i915_error_state_buf_release(&error_str);
 569
 570         return ret ?: ret_count;
 571 }
 572
 573 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
 574                                  struct bin_attribute *attr, char *buf,
 575                                  loff_t off, size_t count)
 576 {
 577         struct device *kdev = container_of(kobj, struct device, kobj);
 578         struct drm_minor *minor = dev_to_drm_minor(kdev);
 579         struct drm_device *dev = minor->dev;
 580         int ret;
 581
 582         DRM_DEBUG_DRIVER("Resetting error state\n");
 583
 584         ret = mutex_lock_interruptible(&dev->struct_mutex);
 585         if (ret)
 586                 return ret;
 587
 588         i915_destroy_error_state(dev);
 589         mutex_unlock(&dev->struct_mutex);
 590
 591         return count;
 592 }
 593
 594 static struct bin_attribute error_state_attr = {
 595         .attr.name = "error",
 596         .attr.mode = S_IRUSR | S_IWUSR,
 597         .size = 0,
 598         .read = error_state_read,
 599         .write = error_state_write,
 600 };
 601
 602 void i915_setup_sysfs(struct drm_device *dev)
 603 {
 604         int ret;
 605
 606 #ifdef CONFIG_PM
 607         if (HAS_RC6(dev)) {
 608                 ret = sysfs_merge_group(&dev->primary->kdev->kobj,
 609                                         &rc6_attr_group);
 610                 if (ret)
 611                         DRM_ERROR("RC6 residency sysfs setup failed\n");
 612         }
 613         if (HAS_RC6p(dev)) {
 614                 ret = sysfs_merge_group(&dev->primary->kdev->kobj,
 615                                         &rc6p_attr_group);
 616                 if (ret)
 617                         DRM_ERROR("RC6p residency sysfs setup failed\n");
 618         }
 619 #endif
 620         if (HAS_L3_DPF(dev)) {
 621                 ret = device_create_bin_file(dev->primary->kdev, &dpf_attrs);
 622                 if (ret)
 623                         DRM_ERROR("l3 parity sysfs setup failed\n");
 624
 625                 if (NUM_L3_SLICES(dev) > 1) {
 626                         ret = device_create_bin_file(dev->primary->kdev,
 627                                                      &dpf_attrs_1);
 628                         if (ret)
 629                                 DRM_ERROR("l3 parity slice 1 setup failed\n");
 630                 }
 631         }
 632
 633         ret = 0;
 634         if (IS_VALLEYVIEW(dev))
 635                 ret = sysfs_create_files(&dev->primary->kdev->kobj, vlv_attrs);
 636         else if (INTEL_INFO(dev)->gen >= 6)
 637                 ret = sysfs_create_files(&dev->primary->kdev->kobj, gen6_attrs);
 638         if (ret)
 639                 DRM_ERROR("RPS sysfs setup failed\n");
 640
 641         ret = sysfs_create_bin_file(&dev->primary->kdev->kobj,
 642                                     &error_state_attr);
 643         if (ret)
 644                 DRM_ERROR("error_state sysfs setup failed\n");
 645 }
 646
 647 void i915_teardown_sysfs(struct drm_device *dev)
 648 {
 649         sysfs_remove_bin_file(&dev->primary->kdev->kobj, &error_state_attr);
 650         if (IS_VALLEYVIEW(dev))
 651                 sysfs_remove_files(&dev->primary->kdev->kobj, vlv_attrs);
 652         else
 653                 sysfs_remove_files(&dev->primary->kdev->kobj, gen6_attrs);
 654         device_remove_bin_file(dev->primary->kdev,  &dpf_attrs_1);
 655         device_remove_bin_file(dev->primary->kdev,  &dpf_attrs);
 656 #ifdef CONFIG_PM
 657         sysfs_unmerge_group(&dev->primary->kdev->kobj, &rc6_attr_group);
 658         sysfs_unmerge_group(&dev->primary->kdev->kobj, &rc6p_attr_group);
 659 #endif
 660 }