2 * Copyright © 2014 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
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11 * The above copyright notice and this permission notice (including the next
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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
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20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
25 * DOC: Frame Buffer Compression (FBC)
27 * FBC tries to save memory bandwidth (and so power consumption) by
28 * compressing the amount of memory used by the display. It is total
29 * transparent to user space and completely handled in the kernel.
31 * The benefits of FBC are mostly visible with solid backgrounds and
32 * variation-less patterns. It comes from keeping the memory footprint small
33 * and having fewer memory pages opened and accessed for refreshing the display.
35 * i915 is responsible to reserve stolen memory for FBC and configure its
36 * offset on proper registers. The hardware takes care of all
37 * compress/decompress. However there are many known cases where we have to
38 * forcibly disable it to allow proper screen updates.
41 #include "intel_drv.h"
44 static inline bool fbc_supported(struct drm_i915_private *dev_priv)
46 return HAS_FBC(dev_priv);
49 static inline bool fbc_on_pipe_a_only(struct drm_i915_private *dev_priv)
51 return IS_HASWELL(dev_priv) || INTEL_GEN(dev_priv) >= 8;
54 static inline bool fbc_on_plane_a_only(struct drm_i915_private *dev_priv)
56 return INTEL_GEN(dev_priv) < 4;
59 static inline bool no_fbc_on_multiple_pipes(struct drm_i915_private *dev_priv)
61 return INTEL_GEN(dev_priv) <= 3;
65 * In some platforms where the CRTC's x:0/y:0 coordinates doesn't match the
66 * frontbuffer's x:0/y:0 coordinates we lie to the hardware about the plane's
67 * origin so the x and y offsets can actually fit the registers. As a
68 * consequence, the fence doesn't really start exactly at the display plane
69 * address we program because it starts at the real start of the buffer, so we
70 * have to take this into consideration here.
72 static unsigned int get_crtc_fence_y_offset(struct intel_crtc *crtc)
74 return crtc->base.y - crtc->adjusted_y;
78 * For SKL+, the plane source size used by the hardware is based on the value we
79 * write to the PLANE_SIZE register. For BDW-, the hardware looks at the value
80 * we wrote to PIPESRC.
82 static void intel_fbc_get_plane_source_size(struct intel_fbc_state_cache *cache,
83 int *width, int *height)
86 *width = cache->plane.src_w;
88 *height = cache->plane.src_h;
91 static int intel_fbc_calculate_cfb_size(struct drm_i915_private *dev_priv,
92 struct intel_fbc_state_cache *cache)
96 intel_fbc_get_plane_source_size(cache, NULL, &lines);
97 if (INTEL_GEN(dev_priv) == 7)
98 lines = min(lines, 2048);
99 else if (INTEL_GEN(dev_priv) >= 8)
100 lines = min(lines, 2560);
102 /* Hardware needs the full buffer stride, not just the active area. */
103 return lines * cache->fb.stride;
106 static void i8xx_fbc_deactivate(struct drm_i915_private *dev_priv)
110 /* Disable compression */
111 fbc_ctl = I915_READ(FBC_CONTROL);
112 if ((fbc_ctl & FBC_CTL_EN) == 0)
115 fbc_ctl &= ~FBC_CTL_EN;
116 I915_WRITE(FBC_CONTROL, fbc_ctl);
118 /* Wait for compressing bit to clear */
119 if (intel_wait_for_register(dev_priv,
120 FBC_STATUS, FBC_STAT_COMPRESSING, 0,
122 DRM_DEBUG_KMS("FBC idle timed out\n");
127 static void i8xx_fbc_activate(struct drm_i915_private *dev_priv)
129 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
134 /* Note: fbc.threshold == 1 for i8xx */
135 cfb_pitch = params->cfb_size / FBC_LL_SIZE;
136 if (params->fb.stride < cfb_pitch)
137 cfb_pitch = params->fb.stride;
139 /* FBC_CTL wants 32B or 64B units */
140 if (IS_GEN2(dev_priv))
141 cfb_pitch = (cfb_pitch / 32) - 1;
143 cfb_pitch = (cfb_pitch / 64) - 1;
146 for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
147 I915_WRITE(FBC_TAG(i), 0);
149 if (IS_GEN4(dev_priv)) {
153 fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
154 fbc_ctl2 |= FBC_CTL_PLANE(params->crtc.plane);
155 I915_WRITE(FBC_CONTROL2, fbc_ctl2);
156 I915_WRITE(FBC_FENCE_OFF, params->crtc.fence_y_offset);
160 fbc_ctl = I915_READ(FBC_CONTROL);
161 fbc_ctl &= 0x3fff << FBC_CTL_INTERVAL_SHIFT;
162 fbc_ctl |= FBC_CTL_EN | FBC_CTL_PERIODIC;
163 if (IS_I945GM(dev_priv))
164 fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
165 fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
166 fbc_ctl |= params->vma->fence->id;
167 I915_WRITE(FBC_CONTROL, fbc_ctl);
170 static bool i8xx_fbc_is_active(struct drm_i915_private *dev_priv)
172 return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
175 static void g4x_fbc_activate(struct drm_i915_private *dev_priv)
177 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
180 dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane) | DPFC_SR_EN;
181 if (params->fb.format->cpp[0] == 2)
182 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
184 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
186 if (params->vma->fence) {
187 dpfc_ctl |= DPFC_CTL_FENCE_EN | params->vma->fence->id;
188 I915_WRITE(DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
190 I915_WRITE(DPFC_FENCE_YOFF, 0);
194 I915_WRITE(DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
197 static void g4x_fbc_deactivate(struct drm_i915_private *dev_priv)
201 /* Disable compression */
202 dpfc_ctl = I915_READ(DPFC_CONTROL);
203 if (dpfc_ctl & DPFC_CTL_EN) {
204 dpfc_ctl &= ~DPFC_CTL_EN;
205 I915_WRITE(DPFC_CONTROL, dpfc_ctl);
209 static bool g4x_fbc_is_active(struct drm_i915_private *dev_priv)
211 return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
214 /* This function forces a CFB recompression through the nuke operation. */
215 static void intel_fbc_recompress(struct drm_i915_private *dev_priv)
217 I915_WRITE(MSG_FBC_REND_STATE, FBC_REND_NUKE);
218 POSTING_READ(MSG_FBC_REND_STATE);
221 static void ilk_fbc_activate(struct drm_i915_private *dev_priv)
223 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
225 int threshold = dev_priv->fbc.threshold;
227 dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane);
228 if (params->fb.format->cpp[0] == 2)
234 dpfc_ctl |= DPFC_CTL_LIMIT_4X;
237 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
240 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
244 if (params->vma->fence) {
245 dpfc_ctl |= DPFC_CTL_FENCE_EN;
246 if (IS_GEN5(dev_priv))
247 dpfc_ctl |= params->vma->fence->id;
248 if (IS_GEN6(dev_priv)) {
249 I915_WRITE(SNB_DPFC_CTL_SA,
250 SNB_CPU_FENCE_ENABLE |
251 params->vma->fence->id);
252 I915_WRITE(DPFC_CPU_FENCE_OFFSET,
253 params->crtc.fence_y_offset);
256 if (IS_GEN6(dev_priv)) {
257 I915_WRITE(SNB_DPFC_CTL_SA, 0);
258 I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
262 I915_WRITE(ILK_DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
263 I915_WRITE(ILK_FBC_RT_BASE,
264 i915_ggtt_offset(params->vma) | ILK_FBC_RT_VALID);
266 I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
268 intel_fbc_recompress(dev_priv);
271 static void ilk_fbc_deactivate(struct drm_i915_private *dev_priv)
275 /* Disable compression */
276 dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
277 if (dpfc_ctl & DPFC_CTL_EN) {
278 dpfc_ctl &= ~DPFC_CTL_EN;
279 I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);
283 static bool ilk_fbc_is_active(struct drm_i915_private *dev_priv)
285 return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
288 static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
290 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
292 int threshold = dev_priv->fbc.threshold;
295 if (IS_IVYBRIDGE(dev_priv))
296 dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.plane);
298 if (params->fb.format->cpp[0] == 2)
304 dpfc_ctl |= DPFC_CTL_LIMIT_4X;
307 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
310 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
314 if (params->vma->fence) {
315 dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
316 I915_WRITE(SNB_DPFC_CTL_SA,
317 SNB_CPU_FENCE_ENABLE |
318 params->vma->fence->id);
319 I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
321 I915_WRITE(SNB_DPFC_CTL_SA,0);
322 I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
325 if (dev_priv->fbc.false_color)
326 dpfc_ctl |= FBC_CTL_FALSE_COLOR;
328 if (IS_IVYBRIDGE(dev_priv)) {
329 /* WaFbcAsynchFlipDisableFbcQueue:ivb */
330 I915_WRITE(ILK_DISPLAY_CHICKEN1,
331 I915_READ(ILK_DISPLAY_CHICKEN1) |
333 } else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
334 /* WaFbcAsynchFlipDisableFbcQueue:hsw,bdw */
335 I915_WRITE(CHICKEN_PIPESL_1(params->crtc.pipe),
336 I915_READ(CHICKEN_PIPESL_1(params->crtc.pipe)) |
340 I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
342 intel_fbc_recompress(dev_priv);
345 static bool intel_fbc_hw_is_active(struct drm_i915_private *dev_priv)
347 if (INTEL_GEN(dev_priv) >= 5)
348 return ilk_fbc_is_active(dev_priv);
349 else if (IS_GM45(dev_priv))
350 return g4x_fbc_is_active(dev_priv);
352 return i8xx_fbc_is_active(dev_priv);
355 static void intel_fbc_hw_activate(struct drm_i915_private *dev_priv)
357 struct intel_fbc *fbc = &dev_priv->fbc;
361 if (INTEL_GEN(dev_priv) >= 7)
362 gen7_fbc_activate(dev_priv);
363 else if (INTEL_GEN(dev_priv) >= 5)
364 ilk_fbc_activate(dev_priv);
365 else if (IS_GM45(dev_priv))
366 g4x_fbc_activate(dev_priv);
368 i8xx_fbc_activate(dev_priv);
371 static void intel_fbc_hw_deactivate(struct drm_i915_private *dev_priv)
373 struct intel_fbc *fbc = &dev_priv->fbc;
377 if (INTEL_GEN(dev_priv) >= 5)
378 ilk_fbc_deactivate(dev_priv);
379 else if (IS_GM45(dev_priv))
380 g4x_fbc_deactivate(dev_priv);
382 i8xx_fbc_deactivate(dev_priv);
386 * intel_fbc_is_active - Is FBC active?
387 * @dev_priv: i915 device instance
389 * This function is used to verify the current state of FBC.
391 * FIXME: This should be tracked in the plane config eventually
392 * instead of queried at runtime for most callers.
394 bool intel_fbc_is_active(struct drm_i915_private *dev_priv)
396 return dev_priv->fbc.active;
399 static void intel_fbc_work_fn(struct work_struct *__work)
401 struct drm_i915_private *dev_priv =
402 container_of(__work, struct drm_i915_private, fbc.work.work);
403 struct intel_fbc *fbc = &dev_priv->fbc;
404 struct intel_fbc_work *work = &fbc->work;
405 struct intel_crtc *crtc = fbc->crtc;
406 struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[crtc->pipe];
408 if (drm_crtc_vblank_get(&crtc->base)) {
409 /* CRTC is now off, leave FBC deactivated */
410 mutex_lock(&fbc->lock);
411 work->scheduled = false;
412 mutex_unlock(&fbc->lock);
417 /* Delay the actual enabling to let pageflipping cease and the
418 * display to settle before starting the compression. Note that
419 * this delay also serves a second purpose: it allows for a
420 * vblank to pass after disabling the FBC before we attempt
421 * to modify the control registers.
423 * WaFbcWaitForVBlankBeforeEnable:ilk,snb
425 * It is also worth mentioning that since work->scheduled_vblank can be
426 * updated multiple times by the other threads, hitting the timeout is
427 * not an error condition. We'll just end up hitting the "goto retry"
430 wait_event_timeout(vblank->queue,
431 drm_crtc_vblank_count(&crtc->base) != work->scheduled_vblank,
432 msecs_to_jiffies(50));
434 mutex_lock(&fbc->lock);
436 /* Were we cancelled? */
437 if (!work->scheduled)
440 /* Were we delayed again while this function was sleeping? */
441 if (drm_crtc_vblank_count(&crtc->base) == work->scheduled_vblank) {
442 mutex_unlock(&fbc->lock);
446 intel_fbc_hw_activate(dev_priv);
448 work->scheduled = false;
451 mutex_unlock(&fbc->lock);
452 drm_crtc_vblank_put(&crtc->base);
455 static void intel_fbc_schedule_activation(struct intel_crtc *crtc)
457 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
458 struct intel_fbc *fbc = &dev_priv->fbc;
459 struct intel_fbc_work *work = &fbc->work;
461 WARN_ON(!mutex_is_locked(&fbc->lock));
462 if (WARN_ON(!fbc->enabled))
465 if (drm_crtc_vblank_get(&crtc->base)) {
466 DRM_ERROR("vblank not available for FBC on pipe %c\n",
467 pipe_name(crtc->pipe));
471 /* It is useless to call intel_fbc_cancel_work() or cancel_work() in
472 * this function since we're not releasing fbc.lock, so it won't have an
473 * opportunity to grab it to discover that it was cancelled. So we just
474 * update the expected jiffy count. */
475 work->scheduled = true;
476 work->scheduled_vblank = drm_crtc_vblank_count(&crtc->base);
477 drm_crtc_vblank_put(&crtc->base);
479 schedule_work(&work->work);
482 static void intel_fbc_deactivate(struct drm_i915_private *dev_priv)
484 struct intel_fbc *fbc = &dev_priv->fbc;
486 WARN_ON(!mutex_is_locked(&fbc->lock));
488 /* Calling cancel_work() here won't help due to the fact that the work
489 * function grabs fbc->lock. Just set scheduled to false so the work
490 * function can know it was cancelled. */
491 fbc->work.scheduled = false;
494 intel_fbc_hw_deactivate(dev_priv);
497 static bool multiple_pipes_ok(struct intel_crtc *crtc,
498 struct intel_plane_state *plane_state)
500 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
501 struct intel_fbc *fbc = &dev_priv->fbc;
502 enum pipe pipe = crtc->pipe;
504 /* Don't even bother tracking anything we don't need. */
505 if (!no_fbc_on_multiple_pipes(dev_priv))
508 if (plane_state->base.visible)
509 fbc->visible_pipes_mask |= (1 << pipe);
511 fbc->visible_pipes_mask &= ~(1 << pipe);
513 return (fbc->visible_pipes_mask & ~(1 << pipe)) != 0;
516 static int find_compression_threshold(struct drm_i915_private *dev_priv,
517 struct drm_mm_node *node,
521 struct i915_ggtt *ggtt = &dev_priv->ggtt;
522 int compression_threshold = 1;
526 /* The FBC hardware for BDW/SKL doesn't have access to the stolen
527 * reserved range size, so it always assumes the maximum (8mb) is used.
528 * If we enable FBC using a CFB on that memory range we'll get FIFO
529 * underruns, even if that range is not reserved by the BIOS. */
530 if (IS_BROADWELL(dev_priv) || IS_GEN9_BC(dev_priv))
531 end = ggtt->stolen_size - 8 * 1024 * 1024;
535 /* HACK: This code depends on what we will do in *_enable_fbc. If that
536 * code changes, this code needs to change as well.
538 * The enable_fbc code will attempt to use one of our 2 compression
539 * thresholds, therefore, in that case, we only have 1 resort.
542 /* Try to over-allocate to reduce reallocations and fragmentation. */
543 ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1,
546 return compression_threshold;
549 /* HW's ability to limit the CFB is 1:4 */
550 if (compression_threshold > 4 ||
551 (fb_cpp == 2 && compression_threshold == 2))
554 ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1,
556 if (ret && INTEL_GEN(dev_priv) <= 4) {
559 compression_threshold <<= 1;
562 return compression_threshold;
566 static int intel_fbc_alloc_cfb(struct intel_crtc *crtc)
568 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
569 struct intel_fbc *fbc = &dev_priv->fbc;
570 struct drm_mm_node *uninitialized_var(compressed_llb);
571 int size, fb_cpp, ret;
573 WARN_ON(drm_mm_node_allocated(&fbc->compressed_fb));
575 size = intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache);
576 fb_cpp = fbc->state_cache.fb.format->cpp[0];
578 ret = find_compression_threshold(dev_priv, &fbc->compressed_fb,
583 DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n");
587 fbc->threshold = ret;
589 if (INTEL_GEN(dev_priv) >= 5)
590 I915_WRITE(ILK_DPFC_CB_BASE, fbc->compressed_fb.start);
591 else if (IS_GM45(dev_priv)) {
592 I915_WRITE(DPFC_CB_BASE, fbc->compressed_fb.start);
594 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
598 ret = i915_gem_stolen_insert_node(dev_priv, compressed_llb,
603 fbc->compressed_llb = compressed_llb;
605 I915_WRITE(FBC_CFB_BASE,
606 dev_priv->mm.stolen_base + fbc->compressed_fb.start);
607 I915_WRITE(FBC_LL_BASE,
608 dev_priv->mm.stolen_base + compressed_llb->start);
611 DRM_DEBUG_KMS("reserved %llu bytes of contiguous stolen space for FBC, threshold: %d\n",
612 fbc->compressed_fb.size, fbc->threshold);
617 kfree(compressed_llb);
618 i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
620 if (drm_mm_initialized(&dev_priv->mm.stolen))
621 pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
625 static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
627 struct intel_fbc *fbc = &dev_priv->fbc;
629 if (drm_mm_node_allocated(&fbc->compressed_fb))
630 i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
632 if (fbc->compressed_llb) {
633 i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb);
634 kfree(fbc->compressed_llb);
638 void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
640 struct intel_fbc *fbc = &dev_priv->fbc;
642 if (!fbc_supported(dev_priv))
645 mutex_lock(&fbc->lock);
646 __intel_fbc_cleanup_cfb(dev_priv);
647 mutex_unlock(&fbc->lock);
650 static bool stride_is_valid(struct drm_i915_private *dev_priv,
653 /* These should have been caught earlier. */
654 WARN_ON(stride < 512);
655 WARN_ON((stride & (64 - 1)) != 0);
657 /* Below are the additional FBC restrictions. */
659 if (IS_GEN2(dev_priv) || IS_GEN3(dev_priv))
660 return stride == 4096 || stride == 8192;
662 if (IS_GEN4(dev_priv) && !IS_G4X(dev_priv) && stride < 2048)
671 static bool pixel_format_is_valid(struct drm_i915_private *dev_priv,
672 uint32_t pixel_format)
674 switch (pixel_format) {
675 case DRM_FORMAT_XRGB8888:
676 case DRM_FORMAT_XBGR8888:
678 case DRM_FORMAT_XRGB1555:
679 case DRM_FORMAT_RGB565:
680 /* 16bpp not supported on gen2 */
681 if (IS_GEN2(dev_priv))
683 /* WaFbcOnly1to1Ratio:ctg */
684 if (IS_G4X(dev_priv))
693 * For some reason, the hardware tracking starts looking at whatever we
694 * programmed as the display plane base address register. It does not look at
695 * the X and Y offset registers. That's why we look at the crtc->adjusted{x,y}
696 * variables instead of just looking at the pipe/plane size.
698 static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc)
700 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
701 struct intel_fbc *fbc = &dev_priv->fbc;
702 unsigned int effective_w, effective_h, max_w, max_h;
704 if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv)) {
707 } else if (IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
715 intel_fbc_get_plane_source_size(&fbc->state_cache, &effective_w,
717 effective_w += crtc->adjusted_x;
718 effective_h += crtc->adjusted_y;
720 return effective_w <= max_w && effective_h <= max_h;
723 static void intel_fbc_update_state_cache(struct intel_crtc *crtc,
724 struct intel_crtc_state *crtc_state,
725 struct intel_plane_state *plane_state)
727 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
728 struct intel_fbc *fbc = &dev_priv->fbc;
729 struct intel_fbc_state_cache *cache = &fbc->state_cache;
730 struct drm_framebuffer *fb = plane_state->base.fb;
734 cache->crtc.mode_flags = crtc_state->base.adjusted_mode.flags;
735 if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
736 cache->crtc.hsw_bdw_pixel_rate = crtc_state->pixel_rate;
738 cache->plane.rotation = plane_state->base.rotation;
740 * Src coordinates are already rotated by 270 degrees for
741 * the 90/270 degree plane rotation cases (to match the
742 * GTT mapping), hence no need to account for rotation here.
744 cache->plane.src_w = drm_rect_width(&plane_state->base.src) >> 16;
745 cache->plane.src_h = drm_rect_height(&plane_state->base.src) >> 16;
746 cache->plane.visible = plane_state->base.visible;
748 if (!cache->plane.visible)
751 cache->fb.format = fb->format;
752 cache->fb.stride = fb->pitches[0];
754 cache->vma = plane_state->vma;
757 static bool intel_fbc_can_activate(struct intel_crtc *crtc)
759 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
760 struct intel_fbc *fbc = &dev_priv->fbc;
761 struct intel_fbc_state_cache *cache = &fbc->state_cache;
763 /* We don't need to use a state cache here since this information is
764 * global for all CRTC.
766 if (fbc->underrun_detected) {
767 fbc->no_fbc_reason = "underrun detected";
772 fbc->no_fbc_reason = "primary plane not visible";
776 if ((cache->crtc.mode_flags & DRM_MODE_FLAG_INTERLACE) ||
777 (cache->crtc.mode_flags & DRM_MODE_FLAG_DBLSCAN)) {
778 fbc->no_fbc_reason = "incompatible mode";
782 if (!intel_fbc_hw_tracking_covers_screen(crtc)) {
783 fbc->no_fbc_reason = "mode too large for compression";
787 /* The use of a CPU fence is mandatory in order to detect writes
788 * by the CPU to the scanout and trigger updates to the FBC.
790 * Note that is possible for a tiled surface to be unmappable (and
791 * so have no fence associated with it) due to aperture constaints
792 * at the time of pinning.
794 if (!cache->vma->fence) {
795 fbc->no_fbc_reason = "framebuffer not tiled or fenced";
798 if (INTEL_GEN(dev_priv) <= 4 && !IS_G4X(dev_priv) &&
799 cache->plane.rotation != DRM_MODE_ROTATE_0) {
800 fbc->no_fbc_reason = "rotation unsupported";
804 if (!stride_is_valid(dev_priv, cache->fb.stride)) {
805 fbc->no_fbc_reason = "framebuffer stride not supported";
809 if (!pixel_format_is_valid(dev_priv, cache->fb.format->format)) {
810 fbc->no_fbc_reason = "pixel format is invalid";
814 /* WaFbcExceedCdClockThreshold:hsw,bdw */
815 if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
816 cache->crtc.hsw_bdw_pixel_rate >= dev_priv->cdclk.hw.cdclk * 95 / 100) {
817 fbc->no_fbc_reason = "pixel rate is too big";
821 /* It is possible for the required CFB size change without a
822 * crtc->disable + crtc->enable since it is possible to change the
823 * stride without triggering a full modeset. Since we try to
824 * over-allocate the CFB, there's a chance we may keep FBC enabled even
825 * if this happens, but if we exceed the current CFB size we'll have to
826 * disable FBC. Notice that it would be possible to disable FBC, wait
827 * for a frame, free the stolen node, then try to reenable FBC in case
828 * we didn't get any invalidate/deactivate calls, but this would require
829 * a lot of tracking just for a specific case. If we conclude it's an
830 * important case, we can implement it later. */
831 if (intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache) >
832 fbc->compressed_fb.size * fbc->threshold) {
833 fbc->no_fbc_reason = "CFB requirements changed";
840 static bool intel_fbc_can_enable(struct drm_i915_private *dev_priv)
842 struct intel_fbc *fbc = &dev_priv->fbc;
844 if (intel_vgpu_active(dev_priv)) {
845 fbc->no_fbc_reason = "VGPU is active";
849 if (!i915.enable_fbc) {
850 fbc->no_fbc_reason = "disabled per module param or by default";
854 if (fbc->underrun_detected) {
855 fbc->no_fbc_reason = "underrun detected";
862 static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
863 struct intel_fbc_reg_params *params)
865 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
866 struct intel_fbc *fbc = &dev_priv->fbc;
867 struct intel_fbc_state_cache *cache = &fbc->state_cache;
869 /* Since all our fields are integer types, use memset here so the
870 * comparison function can rely on memcmp because the padding will be
872 memset(params, 0, sizeof(*params));
874 params->vma = cache->vma;
876 params->crtc.pipe = crtc->pipe;
877 params->crtc.plane = crtc->plane;
878 params->crtc.fence_y_offset = get_crtc_fence_y_offset(crtc);
880 params->fb.format = cache->fb.format;
881 params->fb.stride = cache->fb.stride;
883 params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);
886 static bool intel_fbc_reg_params_equal(struct intel_fbc_reg_params *params1,
887 struct intel_fbc_reg_params *params2)
889 /* We can use this since intel_fbc_get_reg_params() does a memset. */
890 return memcmp(params1, params2, sizeof(*params1)) == 0;
893 void intel_fbc_pre_update(struct intel_crtc *crtc,
894 struct intel_crtc_state *crtc_state,
895 struct intel_plane_state *plane_state)
897 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
898 struct intel_fbc *fbc = &dev_priv->fbc;
900 if (!fbc_supported(dev_priv))
903 mutex_lock(&fbc->lock);
905 if (!multiple_pipes_ok(crtc, plane_state)) {
906 fbc->no_fbc_reason = "more than one pipe active";
910 if (!fbc->enabled || fbc->crtc != crtc)
913 intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
916 intel_fbc_deactivate(dev_priv);
918 mutex_unlock(&fbc->lock);
921 static void __intel_fbc_post_update(struct intel_crtc *crtc)
923 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
924 struct intel_fbc *fbc = &dev_priv->fbc;
925 struct intel_fbc_reg_params old_params;
927 WARN_ON(!mutex_is_locked(&fbc->lock));
929 if (!fbc->enabled || fbc->crtc != crtc)
932 if (!intel_fbc_can_activate(crtc)) {
933 WARN_ON(fbc->active);
937 old_params = fbc->params;
938 intel_fbc_get_reg_params(crtc, &fbc->params);
940 /* If the scanout has not changed, don't modify the FBC settings.
941 * Note that we make the fundamental assumption that the fb->obj
942 * cannot be unpinned (and have its GTT offset and fence revoked)
943 * without first being decoupled from the scanout and FBC disabled.
946 intel_fbc_reg_params_equal(&old_params, &fbc->params))
949 intel_fbc_deactivate(dev_priv);
950 intel_fbc_schedule_activation(crtc);
951 fbc->no_fbc_reason = "FBC enabled (active or scheduled)";
954 void intel_fbc_post_update(struct intel_crtc *crtc)
956 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
957 struct intel_fbc *fbc = &dev_priv->fbc;
959 if (!fbc_supported(dev_priv))
962 mutex_lock(&fbc->lock);
963 __intel_fbc_post_update(crtc);
964 mutex_unlock(&fbc->lock);
967 static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
970 return to_intel_plane(fbc->crtc->base.primary)->frontbuffer_bit;
972 return fbc->possible_framebuffer_bits;
975 void intel_fbc_invalidate(struct drm_i915_private *dev_priv,
976 unsigned int frontbuffer_bits,
977 enum fb_op_origin origin)
979 struct intel_fbc *fbc = &dev_priv->fbc;
981 if (!fbc_supported(dev_priv))
984 if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
987 mutex_lock(&fbc->lock);
989 fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
991 if (fbc->enabled && fbc->busy_bits)
992 intel_fbc_deactivate(dev_priv);
994 mutex_unlock(&fbc->lock);
997 void intel_fbc_flush(struct drm_i915_private *dev_priv,
998 unsigned int frontbuffer_bits, enum fb_op_origin origin)
1000 struct intel_fbc *fbc = &dev_priv->fbc;
1002 if (!fbc_supported(dev_priv))
1005 mutex_lock(&fbc->lock);
1007 fbc->busy_bits &= ~frontbuffer_bits;
1009 if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
1012 if (!fbc->busy_bits && fbc->enabled &&
1013 (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
1015 intel_fbc_recompress(dev_priv);
1017 __intel_fbc_post_update(fbc->crtc);
1021 mutex_unlock(&fbc->lock);
1025 * intel_fbc_choose_crtc - select a CRTC to enable FBC on
1026 * @dev_priv: i915 device instance
1027 * @state: the atomic state structure
1029 * This function looks at the proposed state for CRTCs and planes, then chooses
1030 * which pipe is going to have FBC by setting intel_crtc_state->enable_fbc to
1033 * Later, intel_fbc_enable is going to look for state->enable_fbc and then maybe
1034 * enable FBC for the chosen CRTC. If it does, it will set dev_priv->fbc.crtc.
1036 void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv,
1037 struct drm_atomic_state *state)
1039 struct intel_fbc *fbc = &dev_priv->fbc;
1040 struct drm_plane *plane;
1041 struct drm_plane_state *plane_state;
1042 bool crtc_chosen = false;
1045 mutex_lock(&fbc->lock);
1047 /* Does this atomic commit involve the CRTC currently tied to FBC? */
1049 !drm_atomic_get_existing_crtc_state(state, &fbc->crtc->base))
1052 if (!intel_fbc_can_enable(dev_priv))
1055 /* Simply choose the first CRTC that is compatible and has a visible
1056 * plane. We could go for fancier schemes such as checking the plane
1057 * size, but this would just affect the few platforms that don't tie FBC
1058 * to pipe or plane A. */
1059 for_each_new_plane_in_state(state, plane, plane_state, i) {
1060 struct intel_plane_state *intel_plane_state =
1061 to_intel_plane_state(plane_state);
1062 struct intel_crtc_state *intel_crtc_state;
1063 struct intel_crtc *crtc = to_intel_crtc(plane_state->crtc);
1065 if (!intel_plane_state->base.visible)
1068 if (fbc_on_pipe_a_only(dev_priv) && crtc->pipe != PIPE_A)
1071 if (fbc_on_plane_a_only(dev_priv) && crtc->plane != PLANE_A)
1074 intel_crtc_state = to_intel_crtc_state(
1075 drm_atomic_get_existing_crtc_state(state, &crtc->base));
1077 intel_crtc_state->enable_fbc = true;
1083 fbc->no_fbc_reason = "no suitable CRTC for FBC";
1086 mutex_unlock(&fbc->lock);
1090 * intel_fbc_enable: tries to enable FBC on the CRTC
1092 * @crtc_state: corresponding &drm_crtc_state for @crtc
1093 * @plane_state: corresponding &drm_plane_state for the primary plane of @crtc
1095 * This function checks if the given CRTC was chosen for FBC, then enables it if
1096 * possible. Notice that it doesn't activate FBC. It is valid to call
1097 * intel_fbc_enable multiple times for the same pipe without an
1098 * intel_fbc_disable in the middle, as long as it is deactivated.
1100 void intel_fbc_enable(struct intel_crtc *crtc,
1101 struct intel_crtc_state *crtc_state,
1102 struct intel_plane_state *plane_state)
1104 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1105 struct intel_fbc *fbc = &dev_priv->fbc;
1107 if (!fbc_supported(dev_priv))
1110 mutex_lock(&fbc->lock);
1113 WARN_ON(fbc->crtc == NULL);
1114 if (fbc->crtc == crtc) {
1115 WARN_ON(!crtc_state->enable_fbc);
1116 WARN_ON(fbc->active);
1121 if (!crtc_state->enable_fbc)
1124 WARN_ON(fbc->active);
1125 WARN_ON(fbc->crtc != NULL);
1127 intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
1128 if (intel_fbc_alloc_cfb(crtc)) {
1129 fbc->no_fbc_reason = "not enough stolen memory";
1133 DRM_DEBUG_KMS("Enabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1134 fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1136 fbc->enabled = true;
1139 mutex_unlock(&fbc->lock);
1143 * __intel_fbc_disable - disable FBC
1144 * @dev_priv: i915 device instance
1146 * This is the low level function that actually disables FBC. Callers should
1147 * grab the FBC lock.
1149 static void __intel_fbc_disable(struct drm_i915_private *dev_priv)
1151 struct intel_fbc *fbc = &dev_priv->fbc;
1152 struct intel_crtc *crtc = fbc->crtc;
1154 WARN_ON(!mutex_is_locked(&fbc->lock));
1155 WARN_ON(!fbc->enabled);
1156 WARN_ON(fbc->active);
1157 WARN_ON(crtc->active);
1159 DRM_DEBUG_KMS("Disabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1161 __intel_fbc_cleanup_cfb(dev_priv);
1163 fbc->enabled = false;
1168 * intel_fbc_disable - disable FBC if it's associated with crtc
1171 * This function disables FBC if it's associated with the provided CRTC.
1173 void intel_fbc_disable(struct intel_crtc *crtc)
1175 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1176 struct intel_fbc *fbc = &dev_priv->fbc;
1178 if (!fbc_supported(dev_priv))
1181 mutex_lock(&fbc->lock);
1182 if (fbc->crtc == crtc)
1183 __intel_fbc_disable(dev_priv);
1184 mutex_unlock(&fbc->lock);
1186 cancel_work_sync(&fbc->work.work);
1190 * intel_fbc_global_disable - globally disable FBC
1191 * @dev_priv: i915 device instance
1193 * This function disables FBC regardless of which CRTC is associated with it.
1195 void intel_fbc_global_disable(struct drm_i915_private *dev_priv)
1197 struct intel_fbc *fbc = &dev_priv->fbc;
1199 if (!fbc_supported(dev_priv))
1202 mutex_lock(&fbc->lock);
1204 __intel_fbc_disable(dev_priv);
1205 mutex_unlock(&fbc->lock);
1207 cancel_work_sync(&fbc->work.work);
1210 static void intel_fbc_underrun_work_fn(struct work_struct *work)
1212 struct drm_i915_private *dev_priv =
1213 container_of(work, struct drm_i915_private, fbc.underrun_work);
1214 struct intel_fbc *fbc = &dev_priv->fbc;
1216 mutex_lock(&fbc->lock);
1218 /* Maybe we were scheduled twice. */
1219 if (fbc->underrun_detected || !fbc->enabled)
1222 DRM_DEBUG_KMS("Disabling FBC due to FIFO underrun.\n");
1223 fbc->underrun_detected = true;
1225 intel_fbc_deactivate(dev_priv);
1227 mutex_unlock(&fbc->lock);
1231 * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
1232 * @dev_priv: i915 device instance
1234 * Without FBC, most underruns are harmless and don't really cause too many
1235 * problems, except for an annoying message on dmesg. With FBC, underruns can
1236 * become black screens or even worse, especially when paired with bad
1237 * watermarks. So in order for us to be on the safe side, completely disable FBC
1238 * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
1239 * already suggests that watermarks may be bad, so try to be as safe as
1242 * This function is called from the IRQ handler.
1244 void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv)
1246 struct intel_fbc *fbc = &dev_priv->fbc;
1248 if (!fbc_supported(dev_priv))
1251 /* There's no guarantee that underrun_detected won't be set to true
1252 * right after this check and before the work is scheduled, but that's
1253 * not a problem since we'll check it again under the work function
1254 * while FBC is locked. This check here is just to prevent us from
1255 * unnecessarily scheduling the work, and it relies on the fact that we
1256 * never switch underrun_detect back to false after it's true. */
1257 if (READ_ONCE(fbc->underrun_detected))
1260 schedule_work(&fbc->underrun_work);
1264 * intel_fbc_init_pipe_state - initialize FBC's CRTC visibility tracking
1265 * @dev_priv: i915 device instance
1267 * The FBC code needs to track CRTC visibility since the older platforms can't
1268 * have FBC enabled while multiple pipes are used. This function does the
1269 * initial setup at driver load to make sure FBC is matching the real hardware.
1271 void intel_fbc_init_pipe_state(struct drm_i915_private *dev_priv)
1273 struct intel_crtc *crtc;
1275 /* Don't even bother tracking anything if we don't need. */
1276 if (!no_fbc_on_multiple_pipes(dev_priv))
1279 for_each_intel_crtc(&dev_priv->drm, crtc)
1280 if (intel_crtc_active(crtc) &&
1281 crtc->base.primary->state->visible)
1282 dev_priv->fbc.visible_pipes_mask |= (1 << crtc->pipe);
1286 * The DDX driver changes its behavior depending on the value it reads from
1287 * i915.enable_fbc, so sanitize it by translating the default value into either
1288 * 0 or 1 in order to allow it to know what's going on.
1290 * Notice that this is done at driver initialization and we still allow user
1291 * space to change the value during runtime without sanitizing it again. IGT
1292 * relies on being able to change i915.enable_fbc at runtime.
1294 static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv)
1296 if (i915.enable_fbc >= 0)
1297 return !!i915.enable_fbc;
1299 if (!HAS_FBC(dev_priv))
1302 /* https://bugs.freedesktop.org/show_bug.cgi?id=108085 */
1303 if (IS_GEMINILAKE(dev_priv))
1306 if (IS_BROADWELL(dev_priv) || INTEL_GEN(dev_priv) >= 9)
1312 static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv)
1314 /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
1315 if (intel_vtd_active() &&
1316 (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) {
1317 DRM_INFO("Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
1325 * intel_fbc_init - Initialize FBC
1326 * @dev_priv: the i915 device
1328 * This function might be called during PM init process.
1330 void intel_fbc_init(struct drm_i915_private *dev_priv)
1332 struct intel_fbc *fbc = &dev_priv->fbc;
1335 INIT_WORK(&fbc->work.work, intel_fbc_work_fn);
1336 INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
1337 mutex_init(&fbc->lock);
1338 fbc->enabled = false;
1339 fbc->active = false;
1340 fbc->work.scheduled = false;
1342 if (need_fbc_vtd_wa(dev_priv))
1343 mkwrite_device_info(dev_priv)->has_fbc = false;
1345 i915.enable_fbc = intel_sanitize_fbc_option(dev_priv);
1346 DRM_DEBUG_KMS("Sanitized enable_fbc value: %d\n", i915.enable_fbc);
1348 if (!HAS_FBC(dev_priv)) {
1349 fbc->no_fbc_reason = "unsupported by this chipset";
1353 for_each_pipe(dev_priv, pipe) {
1354 fbc->possible_framebuffer_bits |=
1355 INTEL_FRONTBUFFER_PRIMARY(pipe);
1357 if (fbc_on_pipe_a_only(dev_priv))
1361 /* This value was pulled out of someone's hat */
1362 if (INTEL_GEN(dev_priv) <= 4 && !IS_GM45(dev_priv))
1363 I915_WRITE(FBC_CONTROL, 500 << FBC_CTL_INTERVAL_SHIFT);
1365 /* We still don't have any sort of hardware state readout for FBC, so
1366 * deactivate it in case the BIOS activated it to make sure software
1367 * matches the hardware state. */
1368 if (intel_fbc_hw_is_active(dev_priv))
1369 intel_fbc_hw_deactivate(dev_priv);