Merge tag 'drm-misc-fixes-2017-11-02' of git://anongit.freedesktop.org/drm/drm-misc...
[sfrench/cifs-2.6.git] / drivers / gpu / drm / i915 / intel_pipe_crc.c
1 /*
2  * Copyright © 2013 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  * Author: Damien Lespiau <damien.lespiau@intel.com>
24  *
25  */
26
27 #include <linux/seq_file.h>
28 #include <linux/circ_buf.h>
29 #include <linux/ctype.h>
30 #include <linux/debugfs.h>
31 #include "intel_drv.h"
32
33 struct pipe_crc_info {
34         const char *name;
35         struct drm_i915_private *dev_priv;
36         enum pipe pipe;
37 };
38
39 static int i915_pipe_crc_open(struct inode *inode, struct file *filep)
40 {
41         struct pipe_crc_info *info = inode->i_private;
42         struct drm_i915_private *dev_priv = info->dev_priv;
43         struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[info->pipe];
44
45         if (info->pipe >= INTEL_INFO(dev_priv)->num_pipes)
46                 return -ENODEV;
47
48         spin_lock_irq(&pipe_crc->lock);
49
50         if (pipe_crc->opened) {
51                 spin_unlock_irq(&pipe_crc->lock);
52                 return -EBUSY; /* already open */
53         }
54
55         pipe_crc->opened = true;
56         filep->private_data = inode->i_private;
57
58         spin_unlock_irq(&pipe_crc->lock);
59
60         return 0;
61 }
62
63 static int i915_pipe_crc_release(struct inode *inode, struct file *filep)
64 {
65         struct pipe_crc_info *info = inode->i_private;
66         struct drm_i915_private *dev_priv = info->dev_priv;
67         struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[info->pipe];
68
69         spin_lock_irq(&pipe_crc->lock);
70         pipe_crc->opened = false;
71         spin_unlock_irq(&pipe_crc->lock);
72
73         return 0;
74 }
75
76 /* (6 fields, 8 chars each, space separated (5) + '\n') */
77 #define PIPE_CRC_LINE_LEN       (6 * 8 + 5 + 1)
78 /* account for \'0' */
79 #define PIPE_CRC_BUFFER_LEN     (PIPE_CRC_LINE_LEN + 1)
80
81 static int pipe_crc_data_count(struct intel_pipe_crc *pipe_crc)
82 {
83         lockdep_assert_held(&pipe_crc->lock);
84         return CIRC_CNT(pipe_crc->head, pipe_crc->tail,
85                         INTEL_PIPE_CRC_ENTRIES_NR);
86 }
87
88 static ssize_t
89 i915_pipe_crc_read(struct file *filep, char __user *user_buf, size_t count,
90                    loff_t *pos)
91 {
92         struct pipe_crc_info *info = filep->private_data;
93         struct drm_i915_private *dev_priv = info->dev_priv;
94         struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[info->pipe];
95         char buf[PIPE_CRC_BUFFER_LEN];
96         int n_entries;
97         ssize_t bytes_read;
98
99         /*
100          * Don't allow user space to provide buffers not big enough to hold
101          * a line of data.
102          */
103         if (count < PIPE_CRC_LINE_LEN)
104                 return -EINVAL;
105
106         if (pipe_crc->source == INTEL_PIPE_CRC_SOURCE_NONE)
107                 return 0;
108
109         /* nothing to read */
110         spin_lock_irq(&pipe_crc->lock);
111         while (pipe_crc_data_count(pipe_crc) == 0) {
112                 int ret;
113
114                 if (filep->f_flags & O_NONBLOCK) {
115                         spin_unlock_irq(&pipe_crc->lock);
116                         return -EAGAIN;
117                 }
118
119                 ret = wait_event_interruptible_lock_irq(pipe_crc->wq,
120                                 pipe_crc_data_count(pipe_crc), pipe_crc->lock);
121                 if (ret) {
122                         spin_unlock_irq(&pipe_crc->lock);
123                         return ret;
124                 }
125         }
126
127         /* We now have one or more entries to read */
128         n_entries = count / PIPE_CRC_LINE_LEN;
129
130         bytes_read = 0;
131         while (n_entries > 0) {
132                 struct intel_pipe_crc_entry *entry =
133                         &pipe_crc->entries[pipe_crc->tail];
134
135                 if (CIRC_CNT(pipe_crc->head, pipe_crc->tail,
136                              INTEL_PIPE_CRC_ENTRIES_NR) < 1)
137                         break;
138
139                 BUILD_BUG_ON_NOT_POWER_OF_2(INTEL_PIPE_CRC_ENTRIES_NR);
140                 pipe_crc->tail = (pipe_crc->tail + 1) &
141                                  (INTEL_PIPE_CRC_ENTRIES_NR - 1);
142
143                 bytes_read += snprintf(buf, PIPE_CRC_BUFFER_LEN,
144                                        "%8u %8x %8x %8x %8x %8x\n",
145                                        entry->frame, entry->crc[0],
146                                        entry->crc[1], entry->crc[2],
147                                        entry->crc[3], entry->crc[4]);
148
149                 spin_unlock_irq(&pipe_crc->lock);
150
151                 if (copy_to_user(user_buf, buf, PIPE_CRC_LINE_LEN))
152                         return -EFAULT;
153
154                 user_buf += PIPE_CRC_LINE_LEN;
155                 n_entries--;
156
157                 spin_lock_irq(&pipe_crc->lock);
158         }
159
160         spin_unlock_irq(&pipe_crc->lock);
161
162         return bytes_read;
163 }
164
165 static const struct file_operations i915_pipe_crc_fops = {
166         .owner = THIS_MODULE,
167         .open = i915_pipe_crc_open,
168         .read = i915_pipe_crc_read,
169         .release = i915_pipe_crc_release,
170 };
171
172 static struct pipe_crc_info i915_pipe_crc_data[I915_MAX_PIPES] = {
173         {
174                 .name = "i915_pipe_A_crc",
175                 .pipe = PIPE_A,
176         },
177         {
178                 .name = "i915_pipe_B_crc",
179                 .pipe = PIPE_B,
180         },
181         {
182                 .name = "i915_pipe_C_crc",
183                 .pipe = PIPE_C,
184         },
185 };
186
187 static const char * const pipe_crc_sources[] = {
188         "none",
189         "plane1",
190         "plane2",
191         "pf",
192         "pipe",
193         "TV",
194         "DP-B",
195         "DP-C",
196         "DP-D",
197         "auto",
198 };
199
200 static const char *pipe_crc_source_name(enum intel_pipe_crc_source source)
201 {
202         BUILD_BUG_ON(ARRAY_SIZE(pipe_crc_sources) != INTEL_PIPE_CRC_SOURCE_MAX);
203         return pipe_crc_sources[source];
204 }
205
206 static int display_crc_ctl_show(struct seq_file *m, void *data)
207 {
208         struct drm_i915_private *dev_priv = m->private;
209         enum pipe pipe;
210
211         for_each_pipe(dev_priv, pipe)
212                 seq_printf(m, "%c %s\n", pipe_name(pipe),
213                            pipe_crc_source_name(dev_priv->pipe_crc[pipe].source));
214
215         return 0;
216 }
217
218 static int display_crc_ctl_open(struct inode *inode, struct file *file)
219 {
220         return single_open(file, display_crc_ctl_show, inode->i_private);
221 }
222
223 static int i8xx_pipe_crc_ctl_reg(enum intel_pipe_crc_source *source,
224                                  uint32_t *val)
225 {
226         if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
227                 *source = INTEL_PIPE_CRC_SOURCE_PIPE;
228
229         switch (*source) {
230         case INTEL_PIPE_CRC_SOURCE_PIPE:
231                 *val = PIPE_CRC_ENABLE | PIPE_CRC_INCLUDE_BORDER_I8XX;
232                 break;
233         case INTEL_PIPE_CRC_SOURCE_NONE:
234                 *val = 0;
235                 break;
236         default:
237                 return -EINVAL;
238         }
239
240         return 0;
241 }
242
243 static int i9xx_pipe_crc_auto_source(struct drm_i915_private *dev_priv,
244                                      enum pipe pipe,
245                                      enum intel_pipe_crc_source *source)
246 {
247         struct drm_device *dev = &dev_priv->drm;
248         struct intel_encoder *encoder;
249         struct intel_crtc *crtc;
250         struct intel_digital_port *dig_port;
251         int ret = 0;
252
253         *source = INTEL_PIPE_CRC_SOURCE_PIPE;
254
255         drm_modeset_lock_all(dev);
256         for_each_intel_encoder(dev, encoder) {
257                 if (!encoder->base.crtc)
258                         continue;
259
260                 crtc = to_intel_crtc(encoder->base.crtc);
261
262                 if (crtc->pipe != pipe)
263                         continue;
264
265                 switch (encoder->type) {
266                 case INTEL_OUTPUT_TVOUT:
267                         *source = INTEL_PIPE_CRC_SOURCE_TV;
268                         break;
269                 case INTEL_OUTPUT_DP:
270                 case INTEL_OUTPUT_EDP:
271                         dig_port = enc_to_dig_port(&encoder->base);
272                         switch (dig_port->port) {
273                         case PORT_B:
274                                 *source = INTEL_PIPE_CRC_SOURCE_DP_B;
275                                 break;
276                         case PORT_C:
277                                 *source = INTEL_PIPE_CRC_SOURCE_DP_C;
278                                 break;
279                         case PORT_D:
280                                 *source = INTEL_PIPE_CRC_SOURCE_DP_D;
281                                 break;
282                         default:
283                                 WARN(1, "nonexisting DP port %c\n",
284                                      port_name(dig_port->port));
285                                 break;
286                         }
287                         break;
288                 default:
289                         break;
290                 }
291         }
292         drm_modeset_unlock_all(dev);
293
294         return ret;
295 }
296
297 static int vlv_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
298                                 enum pipe pipe,
299                                 enum intel_pipe_crc_source *source,
300                                 uint32_t *val)
301 {
302         bool need_stable_symbols = false;
303
304         if (*source == INTEL_PIPE_CRC_SOURCE_AUTO) {
305                 int ret = i9xx_pipe_crc_auto_source(dev_priv, pipe, source);
306                 if (ret)
307                         return ret;
308         }
309
310         switch (*source) {
311         case INTEL_PIPE_CRC_SOURCE_PIPE:
312                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_VLV;
313                 break;
314         case INTEL_PIPE_CRC_SOURCE_DP_B:
315                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_B_VLV;
316                 need_stable_symbols = true;
317                 break;
318         case INTEL_PIPE_CRC_SOURCE_DP_C:
319                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_C_VLV;
320                 need_stable_symbols = true;
321                 break;
322         case INTEL_PIPE_CRC_SOURCE_DP_D:
323                 if (!IS_CHERRYVIEW(dev_priv))
324                         return -EINVAL;
325                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_D_VLV;
326                 need_stable_symbols = true;
327                 break;
328         case INTEL_PIPE_CRC_SOURCE_NONE:
329                 *val = 0;
330                 break;
331         default:
332                 return -EINVAL;
333         }
334
335         /*
336          * When the pipe CRC tap point is after the transcoders we need
337          * to tweak symbol-level features to produce a deterministic series of
338          * symbols for a given frame. We need to reset those features only once
339          * a frame (instead of every nth symbol):
340          *   - DC-balance: used to ensure a better clock recovery from the data
341          *     link (SDVO)
342          *   - DisplayPort scrambling: used for EMI reduction
343          */
344         if (need_stable_symbols) {
345                 uint32_t tmp = I915_READ(PORT_DFT2_G4X);
346
347                 tmp |= DC_BALANCE_RESET_VLV;
348                 switch (pipe) {
349                 case PIPE_A:
350                         tmp |= PIPE_A_SCRAMBLE_RESET;
351                         break;
352                 case PIPE_B:
353                         tmp |= PIPE_B_SCRAMBLE_RESET;
354                         break;
355                 case PIPE_C:
356                         tmp |= PIPE_C_SCRAMBLE_RESET;
357                         break;
358                 default:
359                         return -EINVAL;
360                 }
361                 I915_WRITE(PORT_DFT2_G4X, tmp);
362         }
363
364         return 0;
365 }
366
367 static int i9xx_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
368                                  enum pipe pipe,
369                                  enum intel_pipe_crc_source *source,
370                                  uint32_t *val)
371 {
372         bool need_stable_symbols = false;
373
374         if (*source == INTEL_PIPE_CRC_SOURCE_AUTO) {
375                 int ret = i9xx_pipe_crc_auto_source(dev_priv, pipe, source);
376                 if (ret)
377                         return ret;
378         }
379
380         switch (*source) {
381         case INTEL_PIPE_CRC_SOURCE_PIPE:
382                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_I9XX;
383                 break;
384         case INTEL_PIPE_CRC_SOURCE_TV:
385                 if (!SUPPORTS_TV(dev_priv))
386                         return -EINVAL;
387                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_TV_PRE;
388                 break;
389         case INTEL_PIPE_CRC_SOURCE_DP_B:
390                 if (!IS_G4X(dev_priv))
391                         return -EINVAL;
392                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_B_G4X;
393                 need_stable_symbols = true;
394                 break;
395         case INTEL_PIPE_CRC_SOURCE_DP_C:
396                 if (!IS_G4X(dev_priv))
397                         return -EINVAL;
398                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_C_G4X;
399                 need_stable_symbols = true;
400                 break;
401         case INTEL_PIPE_CRC_SOURCE_DP_D:
402                 if (!IS_G4X(dev_priv))
403                         return -EINVAL;
404                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_D_G4X;
405                 need_stable_symbols = true;
406                 break;
407         case INTEL_PIPE_CRC_SOURCE_NONE:
408                 *val = 0;
409                 break;
410         default:
411                 return -EINVAL;
412         }
413
414         /*
415          * When the pipe CRC tap point is after the transcoders we need
416          * to tweak symbol-level features to produce a deterministic series of
417          * symbols for a given frame. We need to reset those features only once
418          * a frame (instead of every nth symbol):
419          *   - DC-balance: used to ensure a better clock recovery from the data
420          *     link (SDVO)
421          *   - DisplayPort scrambling: used for EMI reduction
422          */
423         if (need_stable_symbols) {
424                 uint32_t tmp = I915_READ(PORT_DFT2_G4X);
425
426                 WARN_ON(!IS_G4X(dev_priv));
427
428                 I915_WRITE(PORT_DFT_I9XX,
429                            I915_READ(PORT_DFT_I9XX) | DC_BALANCE_RESET);
430
431                 if (pipe == PIPE_A)
432                         tmp |= PIPE_A_SCRAMBLE_RESET;
433                 else
434                         tmp |= PIPE_B_SCRAMBLE_RESET;
435
436                 I915_WRITE(PORT_DFT2_G4X, tmp);
437         }
438
439         return 0;
440 }
441
442 static void vlv_undo_pipe_scramble_reset(struct drm_i915_private *dev_priv,
443                                          enum pipe pipe)
444 {
445         uint32_t tmp = I915_READ(PORT_DFT2_G4X);
446
447         switch (pipe) {
448         case PIPE_A:
449                 tmp &= ~PIPE_A_SCRAMBLE_RESET;
450                 break;
451         case PIPE_B:
452                 tmp &= ~PIPE_B_SCRAMBLE_RESET;
453                 break;
454         case PIPE_C:
455                 tmp &= ~PIPE_C_SCRAMBLE_RESET;
456                 break;
457         default:
458                 return;
459         }
460         if (!(tmp & PIPE_SCRAMBLE_RESET_MASK))
461                 tmp &= ~DC_BALANCE_RESET_VLV;
462         I915_WRITE(PORT_DFT2_G4X, tmp);
463
464 }
465
466 static void g4x_undo_pipe_scramble_reset(struct drm_i915_private *dev_priv,
467                                          enum pipe pipe)
468 {
469         uint32_t tmp = I915_READ(PORT_DFT2_G4X);
470
471         if (pipe == PIPE_A)
472                 tmp &= ~PIPE_A_SCRAMBLE_RESET;
473         else
474                 tmp &= ~PIPE_B_SCRAMBLE_RESET;
475         I915_WRITE(PORT_DFT2_G4X, tmp);
476
477         if (!(tmp & PIPE_SCRAMBLE_RESET_MASK)) {
478                 I915_WRITE(PORT_DFT_I9XX,
479                            I915_READ(PORT_DFT_I9XX) & ~DC_BALANCE_RESET);
480         }
481 }
482
483 static int ilk_pipe_crc_ctl_reg(enum intel_pipe_crc_source *source,
484                                 uint32_t *val)
485 {
486         if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
487                 *source = INTEL_PIPE_CRC_SOURCE_PIPE;
488
489         switch (*source) {
490         case INTEL_PIPE_CRC_SOURCE_PLANE1:
491                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PRIMARY_ILK;
492                 break;
493         case INTEL_PIPE_CRC_SOURCE_PLANE2:
494                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_SPRITE_ILK;
495                 break;
496         case INTEL_PIPE_CRC_SOURCE_PIPE:
497                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_ILK;
498                 break;
499         case INTEL_PIPE_CRC_SOURCE_NONE:
500                 *val = 0;
501                 break;
502         default:
503                 return -EINVAL;
504         }
505
506         return 0;
507 }
508
509 static void hsw_pipe_A_crc_wa(struct drm_i915_private *dev_priv,
510                               bool enable)
511 {
512         struct drm_device *dev = &dev_priv->drm;
513         struct intel_crtc *crtc = intel_get_crtc_for_pipe(dev_priv, PIPE_A);
514         struct intel_crtc_state *pipe_config;
515         struct drm_atomic_state *state;
516         struct drm_modeset_acquire_ctx ctx;
517         int ret = 0;
518
519         drm_modeset_acquire_init(&ctx, 0);
520
521         state = drm_atomic_state_alloc(dev);
522         if (!state) {
523                 ret = -ENOMEM;
524                 goto unlock;
525         }
526
527         state->acquire_ctx = &ctx;
528
529 retry:
530         pipe_config = intel_atomic_get_crtc_state(state, crtc);
531         if (IS_ERR(pipe_config)) {
532                 ret = PTR_ERR(pipe_config);
533                 goto put_state;
534         }
535
536         if (HAS_IPS(dev_priv)) {
537                 /*
538                  * When IPS gets enabled, the pipe CRC changes. Since IPS gets
539                  * enabled and disabled dynamically based on package C states,
540                  * user space can't make reliable use of the CRCs, so let's just
541                  * completely disable it.
542                  */
543                 pipe_config->ips_force_disable = enable;
544                 if (pipe_config->ips_enabled == enable)
545                         pipe_config->base.connectors_changed = true;
546         }
547
548         if (IS_HASWELL(dev_priv)) {
549                 pipe_config->pch_pfit.force_thru = enable;
550                 if (pipe_config->cpu_transcoder == TRANSCODER_EDP &&
551                     pipe_config->pch_pfit.enabled != enable)
552                         pipe_config->base.connectors_changed = true;
553         }
554
555         ret = drm_atomic_commit(state);
556
557 put_state:
558         if (ret == -EDEADLK) {
559                 drm_atomic_state_clear(state);
560                 drm_modeset_backoff(&ctx);
561                 goto retry;
562         }
563
564         drm_atomic_state_put(state);
565 unlock:
566         WARN(ret, "Toggling workaround to %i returns %i\n", enable, ret);
567         drm_modeset_drop_locks(&ctx);
568         drm_modeset_acquire_fini(&ctx);
569 }
570
571 static int ivb_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
572                                 enum pipe pipe,
573                                 enum intel_pipe_crc_source *source,
574                                 uint32_t *val)
575 {
576         if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
577                 *source = INTEL_PIPE_CRC_SOURCE_PF;
578
579         switch (*source) {
580         case INTEL_PIPE_CRC_SOURCE_PLANE1:
581                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PRIMARY_IVB;
582                 break;
583         case INTEL_PIPE_CRC_SOURCE_PLANE2:
584                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_SPRITE_IVB;
585                 break;
586         case INTEL_PIPE_CRC_SOURCE_PF:
587                 if ((IS_HASWELL(dev_priv) ||
588                      IS_BROADWELL(dev_priv)) && pipe == PIPE_A)
589                         hsw_pipe_A_crc_wa(dev_priv, true);
590
591                 *val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PF_IVB;
592                 break;
593         case INTEL_PIPE_CRC_SOURCE_NONE:
594                 *val = 0;
595                 break;
596         default:
597                 return -EINVAL;
598         }
599
600         return 0;
601 }
602
603 static int get_new_crc_ctl_reg(struct drm_i915_private *dev_priv,
604                                enum pipe pipe,
605                                enum intel_pipe_crc_source *source, u32 *val)
606 {
607         if (IS_GEN2(dev_priv))
608                 return i8xx_pipe_crc_ctl_reg(source, val);
609         else if (INTEL_GEN(dev_priv) < 5)
610                 return i9xx_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
611         else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
612                 return vlv_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
613         else if (IS_GEN5(dev_priv) || IS_GEN6(dev_priv))
614                 return ilk_pipe_crc_ctl_reg(source, val);
615         else
616                 return ivb_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
617 }
618
619 static int pipe_crc_set_source(struct drm_i915_private *dev_priv,
620                                enum pipe pipe,
621                                enum intel_pipe_crc_source source)
622 {
623         struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe];
624         enum intel_display_power_domain power_domain;
625         u32 val = 0; /* shut up gcc */
626         int ret;
627
628         if (pipe_crc->source == source)
629                 return 0;
630
631         /* forbid changing the source without going back to 'none' */
632         if (pipe_crc->source && source)
633                 return -EINVAL;
634
635         power_domain = POWER_DOMAIN_PIPE(pipe);
636         if (!intel_display_power_get_if_enabled(dev_priv, power_domain)) {
637                 DRM_DEBUG_KMS("Trying to capture CRC while pipe is off\n");
638                 return -EIO;
639         }
640
641         ret = get_new_crc_ctl_reg(dev_priv, pipe, &source, &val);
642         if (ret != 0)
643                 goto out;
644
645         /* none -> real source transition */
646         if (source) {
647                 struct intel_pipe_crc_entry *entries;
648
649                 DRM_DEBUG_DRIVER("collecting CRCs for pipe %c, %s\n",
650                                  pipe_name(pipe), pipe_crc_source_name(source));
651
652                 entries = kcalloc(INTEL_PIPE_CRC_ENTRIES_NR,
653                                   sizeof(pipe_crc->entries[0]),
654                                   GFP_KERNEL);
655                 if (!entries) {
656                         ret = -ENOMEM;
657                         goto out;
658                 }
659
660                 spin_lock_irq(&pipe_crc->lock);
661                 kfree(pipe_crc->entries);
662                 pipe_crc->entries = entries;
663                 pipe_crc->head = 0;
664                 pipe_crc->tail = 0;
665                 spin_unlock_irq(&pipe_crc->lock);
666         }
667
668         pipe_crc->source = source;
669
670         I915_WRITE(PIPE_CRC_CTL(pipe), val);
671         POSTING_READ(PIPE_CRC_CTL(pipe));
672
673         /* real source -> none transition */
674         if (!source) {
675                 struct intel_pipe_crc_entry *entries;
676                 struct intel_crtc *crtc = intel_get_crtc_for_pipe(dev_priv,
677                                                                   pipe);
678
679                 DRM_DEBUG_DRIVER("stopping CRCs for pipe %c\n",
680                                  pipe_name(pipe));
681
682                 drm_modeset_lock(&crtc->base.mutex, NULL);
683                 if (crtc->base.state->active)
684                         intel_wait_for_vblank(dev_priv, pipe);
685                 drm_modeset_unlock(&crtc->base.mutex);
686
687                 spin_lock_irq(&pipe_crc->lock);
688                 entries = pipe_crc->entries;
689                 pipe_crc->entries = NULL;
690                 pipe_crc->head = 0;
691                 pipe_crc->tail = 0;
692                 spin_unlock_irq(&pipe_crc->lock);
693
694                 kfree(entries);
695
696                 if (IS_G4X(dev_priv))
697                         g4x_undo_pipe_scramble_reset(dev_priv, pipe);
698                 else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
699                         vlv_undo_pipe_scramble_reset(dev_priv, pipe);
700                 else if ((IS_HASWELL(dev_priv) ||
701                           IS_BROADWELL(dev_priv)) && pipe == PIPE_A)
702                         hsw_pipe_A_crc_wa(dev_priv, false);
703         }
704
705         ret = 0;
706
707 out:
708         intel_display_power_put(dev_priv, power_domain);
709
710         return ret;
711 }
712
713 /*
714  * Parse pipe CRC command strings:
715  *   command: wsp* object wsp+ name wsp+ source wsp*
716  *   object: 'pipe'
717  *   name: (A | B | C)
718  *   source: (none | plane1 | plane2 | pf)
719  *   wsp: (#0x20 | #0x9 | #0xA)+
720  *
721  * eg.:
722  *  "pipe A plane1"  ->  Start CRC computations on plane1 of pipe A
723  *  "pipe A none"    ->  Stop CRC
724  */
725 static int display_crc_ctl_tokenize(char *buf, char *words[], int max_words)
726 {
727         int n_words = 0;
728
729         while (*buf) {
730                 char *end;
731
732                 /* skip leading white space */
733                 buf = skip_spaces(buf);
734                 if (!*buf)
735                         break;  /* end of buffer */
736
737                 /* find end of word */
738                 for (end = buf; *end && !isspace(*end); end++)
739                         ;
740
741                 if (n_words == max_words) {
742                         DRM_DEBUG_DRIVER("too many words, allowed <= %d\n",
743                                          max_words);
744                         return -EINVAL; /* ran out of words[] before bytes */
745                 }
746
747                 if (*end)
748                         *end++ = '\0';
749                 words[n_words++] = buf;
750                 buf = end;
751         }
752
753         return n_words;
754 }
755
756 enum intel_pipe_crc_object {
757         PIPE_CRC_OBJECT_PIPE,
758 };
759
760 static const char * const pipe_crc_objects[] = {
761         "pipe",
762 };
763
764 static int
765 display_crc_ctl_parse_object(const char *buf, enum intel_pipe_crc_object *o)
766 {
767         int i;
768
769         for (i = 0; i < ARRAY_SIZE(pipe_crc_objects); i++)
770                 if (!strcmp(buf, pipe_crc_objects[i])) {
771                         *o = i;
772                         return 0;
773                 }
774
775         return -EINVAL;
776 }
777
778 static int display_crc_ctl_parse_pipe(struct drm_i915_private *dev_priv,
779                                       const char *buf, enum pipe *pipe)
780 {
781         const char name = buf[0];
782
783         if (name < 'A' || name >= pipe_name(INTEL_INFO(dev_priv)->num_pipes))
784                 return -EINVAL;
785
786         *pipe = name - 'A';
787
788         return 0;
789 }
790
791 static int
792 display_crc_ctl_parse_source(const char *buf, enum intel_pipe_crc_source *s)
793 {
794         int i;
795
796         if (!buf) {
797                 *s = INTEL_PIPE_CRC_SOURCE_NONE;
798                 return 0;
799         }
800
801         for (i = 0; i < ARRAY_SIZE(pipe_crc_sources); i++)
802                 if (!strcmp(buf, pipe_crc_sources[i])) {
803                         *s = i;
804                         return 0;
805                 }
806
807         return -EINVAL;
808 }
809
810 static int display_crc_ctl_parse(struct drm_i915_private *dev_priv,
811                                  char *buf, size_t len)
812 {
813 #define N_WORDS 3
814         int n_words;
815         char *words[N_WORDS];
816         enum pipe pipe;
817         enum intel_pipe_crc_object object;
818         enum intel_pipe_crc_source source;
819
820         n_words = display_crc_ctl_tokenize(buf, words, N_WORDS);
821         if (n_words != N_WORDS) {
822                 DRM_DEBUG_DRIVER("tokenize failed, a command is %d words\n",
823                                  N_WORDS);
824                 return -EINVAL;
825         }
826
827         if (display_crc_ctl_parse_object(words[0], &object) < 0) {
828                 DRM_DEBUG_DRIVER("unknown object %s\n", words[0]);
829                 return -EINVAL;
830         }
831
832         if (display_crc_ctl_parse_pipe(dev_priv, words[1], &pipe) < 0) {
833                 DRM_DEBUG_DRIVER("unknown pipe %s\n", words[1]);
834                 return -EINVAL;
835         }
836
837         if (display_crc_ctl_parse_source(words[2], &source) < 0) {
838                 DRM_DEBUG_DRIVER("unknown source %s\n", words[2]);
839                 return -EINVAL;
840         }
841
842         return pipe_crc_set_source(dev_priv, pipe, source);
843 }
844
845 static ssize_t display_crc_ctl_write(struct file *file, const char __user *ubuf,
846                                      size_t len, loff_t *offp)
847 {
848         struct seq_file *m = file->private_data;
849         struct drm_i915_private *dev_priv = m->private;
850         char *tmpbuf;
851         int ret;
852
853         if (len == 0)
854                 return 0;
855
856         if (len > PAGE_SIZE - 1) {
857                 DRM_DEBUG_DRIVER("expected <%lu bytes into pipe crc control\n",
858                                  PAGE_SIZE);
859                 return -E2BIG;
860         }
861
862         tmpbuf = memdup_user_nul(ubuf, len);
863         if (IS_ERR(tmpbuf))
864                 return PTR_ERR(tmpbuf);
865
866         ret = display_crc_ctl_parse(dev_priv, tmpbuf, len);
867
868         kfree(tmpbuf);
869         if (ret < 0)
870                 return ret;
871
872         *offp += len;
873         return len;
874 }
875
876 const struct file_operations i915_display_crc_ctl_fops = {
877         .owner = THIS_MODULE,
878         .open = display_crc_ctl_open,
879         .read = seq_read,
880         .llseek = seq_lseek,
881         .release = single_release,
882         .write = display_crc_ctl_write
883 };
884
885 void intel_display_crc_init(struct drm_i915_private *dev_priv)
886 {
887         enum pipe pipe;
888
889         for_each_pipe(dev_priv, pipe) {
890                 struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe];
891
892                 pipe_crc->opened = false;
893                 spin_lock_init(&pipe_crc->lock);
894                 init_waitqueue_head(&pipe_crc->wq);
895         }
896 }
897
898 int intel_pipe_crc_create(struct drm_minor *minor)
899 {
900         struct drm_i915_private *dev_priv = to_i915(minor->dev);
901         struct dentry *ent;
902         int i;
903
904         for (i = 0; i < ARRAY_SIZE(i915_pipe_crc_data); i++) {
905                 struct pipe_crc_info *info = &i915_pipe_crc_data[i];
906
907                 info->dev_priv = dev_priv;
908                 ent = debugfs_create_file(info->name, S_IRUGO,
909                                           minor->debugfs_root, info,
910                                           &i915_pipe_crc_fops);
911                 if (!ent)
912                         return -ENOMEM;
913         }
914
915         return 0;
916 }
917
918 int intel_crtc_set_crc_source(struct drm_crtc *crtc, const char *source_name,
919                               size_t *values_cnt)
920 {
921         struct drm_i915_private *dev_priv = crtc->dev->dev_private;
922         struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[crtc->index];
923         enum intel_display_power_domain power_domain;
924         enum intel_pipe_crc_source source;
925         u32 val = 0; /* shut up gcc */
926         int ret = 0;
927
928         if (display_crc_ctl_parse_source(source_name, &source) < 0) {
929                 DRM_DEBUG_DRIVER("unknown source %s\n", source_name);
930                 return -EINVAL;
931         }
932
933         power_domain = POWER_DOMAIN_PIPE(crtc->index);
934         if (!intel_display_power_get_if_enabled(dev_priv, power_domain)) {
935                 DRM_DEBUG_KMS("Trying to capture CRC while pipe is off\n");
936                 return -EIO;
937         }
938
939         ret = get_new_crc_ctl_reg(dev_priv, crtc->index, &source, &val);
940         if (ret != 0)
941                 goto out;
942
943         I915_WRITE(PIPE_CRC_CTL(crtc->index), val);
944         POSTING_READ(PIPE_CRC_CTL(crtc->index));
945
946         if (!source) {
947                 if (IS_G4X(dev_priv))
948                         g4x_undo_pipe_scramble_reset(dev_priv, crtc->index);
949                 else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
950                         vlv_undo_pipe_scramble_reset(dev_priv, crtc->index);
951                 else if ((IS_HASWELL(dev_priv) ||
952                           IS_BROADWELL(dev_priv)) && crtc->index == PIPE_A)
953                         hsw_pipe_A_crc_wa(dev_priv, false);
954         }
955
956         pipe_crc->skipped = 0;
957         *values_cnt = 5;
958
959 out:
960         intel_display_power_put(dev_priv, power_domain);
961
962         return ret;
963 }