1 /*
2 * Copyright © 2014 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 * Daniel Vetter <daniel.vetter@ffwll.ch>
25 *
26 */
27
28 #include "i915_drv.h"
29 #include "i915_reg.h"
30 #include "intel_de.h"
31 #include "intel_display_irq.h"
32 #include "intel_display_trace.h"
33 #include "intel_display_types.h"
34 #include "intel_fbc.h"
35 #include "intel_fifo_underrun.h"
36 #include "intel_pch_display.h"
37
38 /**
39 * DOC: fifo underrun handling
40 *
41 * The i915 driver checks for display fifo underruns using the interrupt signals
42 * provided by the hardware. This is enabled by default and fairly useful to
43 * debug display issues, especially watermark settings.
44 *
45 * If an underrun is detected this is logged into dmesg. To avoid flooding logs
46 * and occupying the cpu underrun interrupts are disabled after the first
47 * occurrence until the next modeset on a given pipe.
48 *
49 * Note that underrun detection on gmch platforms is a bit more ugly since there
50 * is no interrupt (despite that the signalling bit is in the PIPESTAT pipe
51 * interrupt register). Also on some other platforms underrun interrupts are
52 * shared, which means that if we detect an underrun we need to disable underrun
53 * reporting on all pipes.
54 *
55 * The code also supports underrun detection on the PCH transcoder.
56 */
57
ivb_can_enable_err_int(struct drm_device * dev)58 static bool ivb_can_enable_err_int(struct drm_device *dev)
59 {
60 struct drm_i915_private *dev_priv = to_i915(dev);
61 struct intel_crtc *crtc;
62 enum pipe pipe;
63
64 lockdep_assert_held(&dev_priv->irq_lock);
65
66 for_each_pipe(dev_priv, pipe) {
67 crtc = intel_crtc_for_pipe(dev_priv, pipe);
68
69 if (crtc->cpu_fifo_underrun_disabled)
70 return false;
71 }
72
73 return true;
74 }
75
cpt_can_enable_serr_int(struct drm_device * dev)76 static bool cpt_can_enable_serr_int(struct drm_device *dev)
77 {
78 struct drm_i915_private *dev_priv = to_i915(dev);
79 enum pipe pipe;
80 struct intel_crtc *crtc;
81
82 lockdep_assert_held(&dev_priv->irq_lock);
83
84 for_each_pipe(dev_priv, pipe) {
85 crtc = intel_crtc_for_pipe(dev_priv, pipe);
86
87 if (crtc->pch_fifo_underrun_disabled)
88 return false;
89 }
90
91 return true;
92 }
93
i9xx_check_fifo_underruns(struct intel_crtc * crtc)94 static void i9xx_check_fifo_underruns(struct intel_crtc *crtc)
95 {
96 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
97 i915_reg_t reg = PIPESTAT(crtc->pipe);
98 u32 enable_mask;
99
100 lockdep_assert_held(&dev_priv->irq_lock);
101
102 if ((intel_de_read(dev_priv, reg) & PIPE_FIFO_UNDERRUN_STATUS) == 0)
103 return;
104
105 enable_mask = i915_pipestat_enable_mask(dev_priv, crtc->pipe);
106 intel_de_write(dev_priv, reg, enable_mask | PIPE_FIFO_UNDERRUN_STATUS);
107 intel_de_posting_read(dev_priv, reg);
108
109 trace_intel_cpu_fifo_underrun(dev_priv, crtc->pipe);
110 drm_err(&dev_priv->drm, "pipe %c underrun\n", pipe_name(crtc->pipe));
111 }
112
i9xx_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pipe,bool enable,bool old)113 static void i9xx_set_fifo_underrun_reporting(struct drm_device *dev,
114 enum pipe pipe,
115 bool enable, bool old)
116 {
117 struct drm_i915_private *dev_priv = to_i915(dev);
118 i915_reg_t reg = PIPESTAT(pipe);
119
120 lockdep_assert_held(&dev_priv->irq_lock);
121
122 if (enable) {
123 u32 enable_mask = i915_pipestat_enable_mask(dev_priv, pipe);
124
125 intel_de_write(dev_priv, reg,
126 enable_mask | PIPE_FIFO_UNDERRUN_STATUS);
127 intel_de_posting_read(dev_priv, reg);
128 } else {
129 if (old && intel_de_read(dev_priv, reg) & PIPE_FIFO_UNDERRUN_STATUS)
130 drm_err(&dev_priv->drm, "pipe %c underrun\n",
131 pipe_name(pipe));
132 }
133 }
134
ilk_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pipe,bool enable)135 static void ilk_set_fifo_underrun_reporting(struct drm_device *dev,
136 enum pipe pipe, bool enable)
137 {
138 struct drm_i915_private *dev_priv = to_i915(dev);
139 u32 bit = (pipe == PIPE_A) ?
140 DE_PIPEA_FIFO_UNDERRUN : DE_PIPEB_FIFO_UNDERRUN;
141
142 if (enable)
143 ilk_enable_display_irq(dev_priv, bit);
144 else
145 ilk_disable_display_irq(dev_priv, bit);
146 }
147
ivb_check_fifo_underruns(struct intel_crtc * crtc)148 static void ivb_check_fifo_underruns(struct intel_crtc *crtc)
149 {
150 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
151 enum pipe pipe = crtc->pipe;
152 u32 err_int = intel_de_read(dev_priv, GEN7_ERR_INT);
153
154 lockdep_assert_held(&dev_priv->irq_lock);
155
156 if ((err_int & ERR_INT_FIFO_UNDERRUN(pipe)) == 0)
157 return;
158
159 intel_de_write(dev_priv, GEN7_ERR_INT, ERR_INT_FIFO_UNDERRUN(pipe));
160 intel_de_posting_read(dev_priv, GEN7_ERR_INT);
161
162 trace_intel_cpu_fifo_underrun(dev_priv, pipe);
163 drm_err(&dev_priv->drm, "fifo underrun on pipe %c\n", pipe_name(pipe));
164 }
165
ivb_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pipe,bool enable,bool old)166 static void ivb_set_fifo_underrun_reporting(struct drm_device *dev,
167 enum pipe pipe, bool enable,
168 bool old)
169 {
170 struct drm_i915_private *dev_priv = to_i915(dev);
171 if (enable) {
172 intel_de_write(dev_priv, GEN7_ERR_INT,
173 ERR_INT_FIFO_UNDERRUN(pipe));
174
175 if (!ivb_can_enable_err_int(dev))
176 return;
177
178 ilk_enable_display_irq(dev_priv, DE_ERR_INT_IVB);
179 } else {
180 ilk_disable_display_irq(dev_priv, DE_ERR_INT_IVB);
181
182 if (old &&
183 intel_de_read(dev_priv, GEN7_ERR_INT) & ERR_INT_FIFO_UNDERRUN(pipe)) {
184 drm_err(&dev_priv->drm,
185 "uncleared fifo underrun on pipe %c\n",
186 pipe_name(pipe));
187 }
188 }
189 }
190
191 static u32
icl_pipe_status_underrun_mask(struct drm_i915_private * dev_priv)192 icl_pipe_status_underrun_mask(struct drm_i915_private *dev_priv)
193 {
194 u32 mask = PIPE_STATUS_UNDERRUN;
195
196 if (DISPLAY_VER(dev_priv) >= 13)
197 mask |= PIPE_STATUS_SOFT_UNDERRUN_XELPD |
198 PIPE_STATUS_HARD_UNDERRUN_XELPD |
199 PIPE_STATUS_PORT_UNDERRUN_XELPD;
200
201 return mask;
202 }
203
bdw_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pipe,bool enable)204 static void bdw_set_fifo_underrun_reporting(struct drm_device *dev,
205 enum pipe pipe, bool enable)
206 {
207 struct drm_i915_private *dev_priv = to_i915(dev);
208 u32 mask = gen8_de_pipe_underrun_mask(dev_priv);
209
210 if (enable) {
211 if (DISPLAY_VER(dev_priv) >= 11)
212 intel_de_write(dev_priv, ICL_PIPESTATUS(pipe),
213 icl_pipe_status_underrun_mask(dev_priv));
214
215 bdw_enable_pipe_irq(dev_priv, pipe, mask);
216 } else {
217 bdw_disable_pipe_irq(dev_priv, pipe, mask);
218 }
219 }
220
ibx_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pch_transcoder,bool enable)221 static void ibx_set_fifo_underrun_reporting(struct drm_device *dev,
222 enum pipe pch_transcoder,
223 bool enable)
224 {
225 struct drm_i915_private *dev_priv = to_i915(dev);
226 u32 bit = (pch_transcoder == PIPE_A) ?
227 SDE_TRANSA_FIFO_UNDER : SDE_TRANSB_FIFO_UNDER;
228
229 if (enable)
230 ibx_enable_display_interrupt(dev_priv, bit);
231 else
232 ibx_disable_display_interrupt(dev_priv, bit);
233 }
234
cpt_check_pch_fifo_underruns(struct intel_crtc * crtc)235 static void cpt_check_pch_fifo_underruns(struct intel_crtc *crtc)
236 {
237 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
238 enum pipe pch_transcoder = crtc->pipe;
239 u32 serr_int = intel_de_read(dev_priv, SERR_INT);
240
241 lockdep_assert_held(&dev_priv->irq_lock);
242
243 if ((serr_int & SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder)) == 0)
244 return;
245
246 intel_de_write(dev_priv, SERR_INT,
247 SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder));
248 intel_de_posting_read(dev_priv, SERR_INT);
249
250 trace_intel_pch_fifo_underrun(dev_priv, pch_transcoder);
251 drm_err(&dev_priv->drm, "pch fifo underrun on pch transcoder %c\n",
252 pipe_name(pch_transcoder));
253 }
254
cpt_set_fifo_underrun_reporting(struct drm_device * dev,enum pipe pch_transcoder,bool enable,bool old)255 static void cpt_set_fifo_underrun_reporting(struct drm_device *dev,
256 enum pipe pch_transcoder,
257 bool enable, bool old)
258 {
259 struct drm_i915_private *dev_priv = to_i915(dev);
260
261 if (enable) {
262 intel_de_write(dev_priv, SERR_INT,
263 SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder));
264
265 if (!cpt_can_enable_serr_int(dev))
266 return;
267
268 ibx_enable_display_interrupt(dev_priv, SDE_ERROR_CPT);
269 } else {
270 ibx_disable_display_interrupt(dev_priv, SDE_ERROR_CPT);
271
272 if (old && intel_de_read(dev_priv, SERR_INT) &
273 SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder)) {
274 drm_err(&dev_priv->drm,
275 "uncleared pch fifo underrun on pch transcoder %c\n",
276 pipe_name(pch_transcoder));
277 }
278 }
279 }
280
__intel_set_cpu_fifo_underrun_reporting(struct drm_device * dev,enum pipe pipe,bool enable)281 static bool __intel_set_cpu_fifo_underrun_reporting(struct drm_device *dev,
282 enum pipe pipe, bool enable)
283 {
284 struct drm_i915_private *dev_priv = to_i915(dev);
285 struct intel_crtc *crtc = intel_crtc_for_pipe(dev_priv, pipe);
286 bool old;
287
288 lockdep_assert_held(&dev_priv->irq_lock);
289
290 old = !crtc->cpu_fifo_underrun_disabled;
291 crtc->cpu_fifo_underrun_disabled = !enable;
292
293 if (HAS_GMCH(dev_priv))
294 i9xx_set_fifo_underrun_reporting(dev, pipe, enable, old);
295 else if (IS_IRONLAKE(dev_priv) || IS_SANDYBRIDGE(dev_priv))
296 ilk_set_fifo_underrun_reporting(dev, pipe, enable);
297 else if (DISPLAY_VER(dev_priv) == 7)
298 ivb_set_fifo_underrun_reporting(dev, pipe, enable, old);
299 else if (DISPLAY_VER(dev_priv) >= 8)
300 bdw_set_fifo_underrun_reporting(dev, pipe, enable);
301
302 return old;
303 }
304
305 /**
306 * intel_set_cpu_fifo_underrun_reporting - set cpu fifo underrrun reporting state
307 * @dev_priv: i915 device instance
308 * @pipe: (CPU) pipe to set state for
309 * @enable: whether underruns should be reported or not
310 *
311 * This function sets the fifo underrun state for @pipe. It is used in the
312 * modeset code to avoid false positives since on many platforms underruns are
313 * expected when disabling or enabling the pipe.
314 *
315 * Notice that on some platforms disabling underrun reports for one pipe
316 * disables for all due to shared interrupts. Actual reporting is still per-pipe
317 * though.
318 *
319 * Returns the previous state of underrun reporting.
320 */
intel_set_cpu_fifo_underrun_reporting(struct drm_i915_private * dev_priv,enum pipe pipe,bool enable)321 bool intel_set_cpu_fifo_underrun_reporting(struct drm_i915_private *dev_priv,
322 enum pipe pipe, bool enable)
323 {
324 unsigned long flags;
325 bool ret;
326
327 spin_lock_irqsave(&dev_priv->irq_lock, flags);
328 ret = __intel_set_cpu_fifo_underrun_reporting(&dev_priv->drm, pipe,
329 enable);
330 spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
331
332 return ret;
333 }
334
335 /**
336 * intel_set_pch_fifo_underrun_reporting - set PCH fifo underrun reporting state
337 * @dev_priv: i915 device instance
338 * @pch_transcoder: the PCH transcoder (same as pipe on IVB and older)
339 * @enable: whether underruns should be reported or not
340 *
341 * This function makes us disable or enable PCH fifo underruns for a specific
342 * PCH transcoder. Notice that on some PCHs (e.g. CPT/PPT), disabling FIFO
343 * underrun reporting for one transcoder may also disable all the other PCH
344 * error interruts for the other transcoders, due to the fact that there's just
345 * one interrupt mask/enable bit for all the transcoders.
346 *
347 * Returns the previous state of underrun reporting.
348 */
intel_set_pch_fifo_underrun_reporting(struct drm_i915_private * dev_priv,enum pipe pch_transcoder,bool enable)349 bool intel_set_pch_fifo_underrun_reporting(struct drm_i915_private *dev_priv,
350 enum pipe pch_transcoder,
351 bool enable)
352 {
353 struct intel_crtc *crtc =
354 intel_crtc_for_pipe(dev_priv, pch_transcoder);
355 unsigned long flags;
356 bool old;
357
358 /*
359 * NOTE: Pre-LPT has a fixed cpu pipe -> pch transcoder mapping, but LPT
360 * has only one pch transcoder A that all pipes can use. To avoid racy
361 * pch transcoder -> pipe lookups from interrupt code simply store the
362 * underrun statistics in crtc A. Since we never expose this anywhere
363 * nor use it outside of the fifo underrun code here using the "wrong"
364 * crtc on LPT won't cause issues.
365 */
366
367 spin_lock_irqsave(&dev_priv->irq_lock, flags);
368
369 old = !crtc->pch_fifo_underrun_disabled;
370 crtc->pch_fifo_underrun_disabled = !enable;
371
372 if (HAS_PCH_IBX(dev_priv))
373 ibx_set_fifo_underrun_reporting(&dev_priv->drm,
374 pch_transcoder,
375 enable);
376 else
377 cpt_set_fifo_underrun_reporting(&dev_priv->drm,
378 pch_transcoder,
379 enable, old);
380
381 spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
382 return old;
383 }
384
385 /**
386 * intel_cpu_fifo_underrun_irq_handler - handle CPU fifo underrun interrupt
387 * @dev_priv: i915 device instance
388 * @pipe: (CPU) pipe to set state for
389 *
390 * This handles a CPU fifo underrun interrupt, generating an underrun warning
391 * into dmesg if underrun reporting is enabled and then disables the underrun
392 * interrupt to avoid an irq storm.
393 */
intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private * dev_priv,enum pipe pipe)394 void intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,
395 enum pipe pipe)
396 {
397 struct intel_crtc *crtc = intel_crtc_for_pipe(dev_priv, pipe);
398 u32 underruns = 0;
399
400 /* We may be called too early in init, thanks BIOS! */
401 if (crtc == NULL)
402 return;
403
404 /* GMCH can't disable fifo underruns, filter them. */
405 if (HAS_GMCH(dev_priv) &&
406 crtc->cpu_fifo_underrun_disabled)
407 return;
408
409 /*
410 * Starting with display version 11, the PIPE_STAT register records
411 * whether an underrun has happened, and on XELPD+, it will also record
412 * whether the underrun was soft/hard and whether it was triggered by
413 * the downstream port logic. We should clear these bits (which use
414 * write-1-to-clear logic) too.
415 *
416 * Note that although the IIR gives us the same underrun and soft/hard
417 * information, PIPE_STAT is the only place we can find out whether
418 * the underrun was caused by the downstream port.
419 */
420 if (DISPLAY_VER(dev_priv) >= 11) {
421 underruns = intel_de_read(dev_priv, ICL_PIPESTATUS(pipe)) &
422 icl_pipe_status_underrun_mask(dev_priv);
423 intel_de_write(dev_priv, ICL_PIPESTATUS(pipe), underruns);
424 }
425
426 if (intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false)) {
427 trace_intel_cpu_fifo_underrun(dev_priv, pipe);
428
429 if (DISPLAY_VER(dev_priv) >= 11)
430 drm_err(&dev_priv->drm, "CPU pipe %c FIFO underrun: %s%s%s%s\n",
431 pipe_name(pipe),
432 underruns & PIPE_STATUS_SOFT_UNDERRUN_XELPD ? "soft," : "",
433 underruns & PIPE_STATUS_HARD_UNDERRUN_XELPD ? "hard," : "",
434 underruns & PIPE_STATUS_PORT_UNDERRUN_XELPD ? "port," : "",
435 underruns & PIPE_STATUS_UNDERRUN ? "transcoder," : "");
436 else
437 drm_err(&dev_priv->drm, "CPU pipe %c FIFO underrun\n", pipe_name(pipe));
438 }
439
440 intel_fbc_handle_fifo_underrun_irq(dev_priv);
441 }
442
443 /**
444 * intel_pch_fifo_underrun_irq_handler - handle PCH fifo underrun interrupt
445 * @dev_priv: i915 device instance
446 * @pch_transcoder: the PCH transcoder (same as pipe on IVB and older)
447 *
448 * This handles a PCH fifo underrun interrupt, generating an underrun warning
449 * into dmesg if underrun reporting is enabled and then disables the underrun
450 * interrupt to avoid an irq storm.
451 */
intel_pch_fifo_underrun_irq_handler(struct drm_i915_private * dev_priv,enum pipe pch_transcoder)452 void intel_pch_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,
453 enum pipe pch_transcoder)
454 {
455 if (intel_set_pch_fifo_underrun_reporting(dev_priv, pch_transcoder,
456 false)) {
457 trace_intel_pch_fifo_underrun(dev_priv, pch_transcoder);
458 drm_err(&dev_priv->drm, "PCH transcoder %c FIFO underrun\n",
459 pipe_name(pch_transcoder));
460 }
461 }
462
463 /**
464 * intel_check_cpu_fifo_underruns - check for CPU fifo underruns immediately
465 * @dev_priv: i915 device instance
466 *
467 * Check for CPU fifo underruns immediately. Useful on IVB/HSW where the shared
468 * error interrupt may have been disabled, and so CPU fifo underruns won't
469 * necessarily raise an interrupt, and on GMCH platforms where underruns never
470 * raise an interrupt.
471 */
intel_check_cpu_fifo_underruns(struct drm_i915_private * dev_priv)472 void intel_check_cpu_fifo_underruns(struct drm_i915_private *dev_priv)
473 {
474 struct intel_crtc *crtc;
475
476 spin_lock_irq(&dev_priv->irq_lock);
477
478 for_each_intel_crtc(&dev_priv->drm, crtc) {
479 if (crtc->cpu_fifo_underrun_disabled)
480 continue;
481
482 if (HAS_GMCH(dev_priv))
483 i9xx_check_fifo_underruns(crtc);
484 else if (DISPLAY_VER(dev_priv) == 7)
485 ivb_check_fifo_underruns(crtc);
486 }
487
488 spin_unlock_irq(&dev_priv->irq_lock);
489 }
490
491 /**
492 * intel_check_pch_fifo_underruns - check for PCH fifo underruns immediately
493 * @dev_priv: i915 device instance
494 *
495 * Check for PCH fifo underruns immediately. Useful on CPT/PPT where the shared
496 * error interrupt may have been disabled, and so PCH fifo underruns won't
497 * necessarily raise an interrupt.
498 */
intel_check_pch_fifo_underruns(struct drm_i915_private * dev_priv)499 void intel_check_pch_fifo_underruns(struct drm_i915_private *dev_priv)
500 {
501 struct intel_crtc *crtc;
502
503 spin_lock_irq(&dev_priv->irq_lock);
504
505 for_each_intel_crtc(&dev_priv->drm, crtc) {
506 if (crtc->pch_fifo_underrun_disabled)
507 continue;
508
509 if (HAS_PCH_CPT(dev_priv))
510 cpt_check_pch_fifo_underruns(crtc);
511 }
512
513 spin_unlock_irq(&dev_priv->irq_lock);
514 }
515
intel_init_fifo_underrun_reporting(struct drm_i915_private * i915,struct intel_crtc * crtc,bool enable)516 void intel_init_fifo_underrun_reporting(struct drm_i915_private *i915,
517 struct intel_crtc *crtc,
518 bool enable)
519 {
520 crtc->cpu_fifo_underrun_disabled = !enable;
521
522 /*
523 * We track the PCH trancoder underrun reporting state
524 * within the crtc. With crtc for pipe A housing the underrun
525 * reporting state for PCH transcoder A, crtc for pipe B housing
526 * it for PCH transcoder B, etc. LPT-H has only PCH transcoder A,
527 * and marking underrun reporting as disabled for the non-existing
528 * PCH transcoders B and C would prevent enabling the south
529 * error interrupt (see cpt_can_enable_serr_int()).
530 */
531 if (intel_has_pch_trancoder(i915, crtc->pipe))
532 crtc->pch_fifo_underrun_disabled = !enable;
533 }
534