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"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
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9 * Software is furnished to do so, subject to the following conditions:
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
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
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 <drm/drm_fourcc.h>
44 #include "i915_trace.h"
45 #include "i915_vgpu.h"
46 #include "intel_display_types.h"
47 #include "intel_fbc.h"
48 #include "intel_frontbuffer.h"
51 * For SKL+, the plane source size used by the hardware is based on the value we
52 * write to the PLANE_SIZE register. For BDW-, the hardware looks at the value
53 * we wrote to PIPESRC.
55 static void intel_fbc_get_plane_source_size(const struct intel_fbc_state_cache *cache,
56 int *width, int *height)
59 *width = cache->plane.src_w;
61 *height = cache->plane.src_h;
64 static int intel_fbc_calculate_cfb_size(struct drm_i915_private *dev_priv,
65 const struct intel_fbc_state_cache *cache)
69 intel_fbc_get_plane_source_size(cache, NULL, &lines);
70 if (IS_GEN(dev_priv, 7))
71 lines = min(lines, 2048);
72 else if (INTEL_GEN(dev_priv) >= 8)
73 lines = min(lines, 2560);
75 /* Hardware needs the full buffer stride, not just the active area. */
76 return lines * cache->fb.stride;
79 static void i8xx_fbc_deactivate(struct drm_i915_private *dev_priv)
83 /* Disable compression */
84 fbc_ctl = intel_de_read(dev_priv, FBC_CONTROL);
85 if ((fbc_ctl & FBC_CTL_EN) == 0)
88 fbc_ctl &= ~FBC_CTL_EN;
89 intel_de_write(dev_priv, FBC_CONTROL, fbc_ctl);
91 /* Wait for compressing bit to clear */
92 if (intel_de_wait_for_clear(dev_priv, FBC_STATUS,
93 FBC_STAT_COMPRESSING, 10)) {
94 drm_dbg_kms(&dev_priv->drm, "FBC idle timed out\n");
99 static void i8xx_fbc_activate(struct drm_i915_private *dev_priv)
101 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
106 /* Note: fbc.threshold == 1 for i8xx */
107 cfb_pitch = params->cfb_size / FBC_LL_SIZE;
108 if (params->fb.stride < cfb_pitch)
109 cfb_pitch = params->fb.stride;
111 /* FBC_CTL wants 32B or 64B units */
112 if (IS_GEN(dev_priv, 2))
113 cfb_pitch = (cfb_pitch / 32) - 1;
115 cfb_pitch = (cfb_pitch / 64) - 1;
118 for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
119 intel_de_write(dev_priv, FBC_TAG(i), 0);
121 if (IS_GEN(dev_priv, 4)) {
125 fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM;
126 fbc_ctl2 |= FBC_CTL_PLANE(params->crtc.i9xx_plane);
127 if (params->fence_id >= 0)
128 fbc_ctl2 |= FBC_CTL_CPU_FENCE;
129 intel_de_write(dev_priv, FBC_CONTROL2, fbc_ctl2);
130 intel_de_write(dev_priv, FBC_FENCE_OFF,
131 params->fence_y_offset);
135 fbc_ctl = FBC_CTL_INTERVAL(params->interval);
136 fbc_ctl |= FBC_CTL_EN | FBC_CTL_PERIODIC;
137 if (IS_I945GM(dev_priv))
138 fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
139 fbc_ctl |= FBC_CTL_STRIDE(cfb_pitch & 0xff);
140 if (params->fence_id >= 0)
141 fbc_ctl |= FBC_CTL_FENCENO(params->fence_id);
142 intel_de_write(dev_priv, FBC_CONTROL, fbc_ctl);
145 static bool i8xx_fbc_is_active(struct drm_i915_private *dev_priv)
147 return intel_de_read(dev_priv, FBC_CONTROL) & FBC_CTL_EN;
150 static void g4x_fbc_activate(struct drm_i915_private *dev_priv)
152 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
155 dpfc_ctl = DPFC_CTL_PLANE(params->crtc.i9xx_plane) | DPFC_SR_EN;
156 if (params->fb.format->cpp[0] == 2)
157 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
159 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
161 if (params->fence_id >= 0) {
162 dpfc_ctl |= DPFC_CTL_FENCE_EN | params->fence_id;
163 intel_de_write(dev_priv, DPFC_FENCE_YOFF,
164 params->fence_y_offset);
166 intel_de_write(dev_priv, DPFC_FENCE_YOFF, 0);
170 intel_de_write(dev_priv, DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
173 static void g4x_fbc_deactivate(struct drm_i915_private *dev_priv)
177 /* Disable compression */
178 dpfc_ctl = intel_de_read(dev_priv, DPFC_CONTROL);
179 if (dpfc_ctl & DPFC_CTL_EN) {
180 dpfc_ctl &= ~DPFC_CTL_EN;
181 intel_de_write(dev_priv, DPFC_CONTROL, dpfc_ctl);
185 static bool g4x_fbc_is_active(struct drm_i915_private *dev_priv)
187 return intel_de_read(dev_priv, DPFC_CONTROL) & DPFC_CTL_EN;
190 static void i8xx_fbc_recompress(struct drm_i915_private *dev_priv)
192 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
193 enum i9xx_plane_id i9xx_plane = params->crtc.i9xx_plane;
195 spin_lock_irq(&dev_priv->uncore.lock);
196 intel_de_write_fw(dev_priv, DSPADDR(i9xx_plane),
197 intel_de_read_fw(dev_priv, DSPADDR(i9xx_plane)));
198 spin_unlock_irq(&dev_priv->uncore.lock);
201 static void i965_fbc_recompress(struct drm_i915_private *dev_priv)
203 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
204 enum i9xx_plane_id i9xx_plane = params->crtc.i9xx_plane;
206 spin_lock_irq(&dev_priv->uncore.lock);
207 intel_de_write_fw(dev_priv, DSPSURF(i9xx_plane),
208 intel_de_read_fw(dev_priv, DSPSURF(i9xx_plane)));
209 spin_unlock_irq(&dev_priv->uncore.lock);
212 /* This function forces a CFB recompression through the nuke operation. */
213 static void snb_fbc_recompress(struct drm_i915_private *dev_priv)
215 struct intel_fbc *fbc = &dev_priv->fbc;
217 trace_intel_fbc_nuke(fbc->crtc);
219 intel_de_write(dev_priv, MSG_FBC_REND_STATE, FBC_REND_NUKE);
220 intel_de_posting_read(dev_priv, MSG_FBC_REND_STATE);
223 static void intel_fbc_recompress(struct drm_i915_private *dev_priv)
225 if (INTEL_GEN(dev_priv) >= 6)
226 snb_fbc_recompress(dev_priv);
227 else if (INTEL_GEN(dev_priv) >= 4)
228 i965_fbc_recompress(dev_priv);
230 i8xx_fbc_recompress(dev_priv);
233 static void ilk_fbc_activate(struct drm_i915_private *dev_priv)
235 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
237 int threshold = dev_priv->fbc.threshold;
239 dpfc_ctl = DPFC_CTL_PLANE(params->crtc.i9xx_plane);
240 if (params->fb.format->cpp[0] == 2)
246 dpfc_ctl |= DPFC_CTL_LIMIT_4X;
249 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
252 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
256 if (params->fence_id >= 0) {
257 dpfc_ctl |= DPFC_CTL_FENCE_EN;
258 if (IS_GEN(dev_priv, 5))
259 dpfc_ctl |= params->fence_id;
260 if (IS_GEN(dev_priv, 6)) {
261 intel_de_write(dev_priv, SNB_DPFC_CTL_SA,
262 SNB_CPU_FENCE_ENABLE | params->fence_id);
263 intel_de_write(dev_priv, DPFC_CPU_FENCE_OFFSET,
264 params->fence_y_offset);
267 if (IS_GEN(dev_priv, 6)) {
268 intel_de_write(dev_priv, SNB_DPFC_CTL_SA, 0);
269 intel_de_write(dev_priv, DPFC_CPU_FENCE_OFFSET, 0);
273 intel_de_write(dev_priv, ILK_DPFC_FENCE_YOFF,
274 params->fence_y_offset);
276 intel_de_write(dev_priv, ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
278 intel_fbc_recompress(dev_priv);
281 static void ilk_fbc_deactivate(struct drm_i915_private *dev_priv)
285 /* Disable compression */
286 dpfc_ctl = intel_de_read(dev_priv, ILK_DPFC_CONTROL);
287 if (dpfc_ctl & DPFC_CTL_EN) {
288 dpfc_ctl &= ~DPFC_CTL_EN;
289 intel_de_write(dev_priv, ILK_DPFC_CONTROL, dpfc_ctl);
293 static bool ilk_fbc_is_active(struct drm_i915_private *dev_priv)
295 return intel_de_read(dev_priv, ILK_DPFC_CONTROL) & DPFC_CTL_EN;
298 static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
300 struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
302 int threshold = dev_priv->fbc.threshold;
304 /* Display WA #0529: skl, kbl, bxt. */
305 if (IS_GEN9_BC(dev_priv) || IS_BROXTON(dev_priv)) {
306 u32 val = intel_de_read(dev_priv, CHICKEN_MISC_4);
308 val &= ~(FBC_STRIDE_OVERRIDE | FBC_STRIDE_MASK);
310 if (params->gen9_wa_cfb_stride)
311 val |= FBC_STRIDE_OVERRIDE | params->gen9_wa_cfb_stride;
313 intel_de_write(dev_priv, CHICKEN_MISC_4, val);
317 if (IS_IVYBRIDGE(dev_priv))
318 dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.i9xx_plane);
320 if (params->fb.format->cpp[0] == 2)
326 dpfc_ctl |= DPFC_CTL_LIMIT_4X;
329 dpfc_ctl |= DPFC_CTL_LIMIT_2X;
332 dpfc_ctl |= DPFC_CTL_LIMIT_1X;
336 if (params->fence_id >= 0) {
337 dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
338 intel_de_write(dev_priv, SNB_DPFC_CTL_SA,
339 SNB_CPU_FENCE_ENABLE | params->fence_id);
340 intel_de_write(dev_priv, DPFC_CPU_FENCE_OFFSET,
341 params->fence_y_offset);
342 } else if (dev_priv->ggtt.num_fences) {
343 intel_de_write(dev_priv, SNB_DPFC_CTL_SA, 0);
344 intel_de_write(dev_priv, DPFC_CPU_FENCE_OFFSET, 0);
347 if (dev_priv->fbc.false_color)
348 dpfc_ctl |= FBC_CTL_FALSE_COLOR;
350 intel_de_write(dev_priv, ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
352 intel_fbc_recompress(dev_priv);
355 static bool intel_fbc_hw_is_active(struct drm_i915_private *dev_priv)
357 if (INTEL_GEN(dev_priv) >= 5)
358 return ilk_fbc_is_active(dev_priv);
359 else if (IS_GM45(dev_priv))
360 return g4x_fbc_is_active(dev_priv);
362 return i8xx_fbc_is_active(dev_priv);
365 static void intel_fbc_hw_activate(struct drm_i915_private *dev_priv)
367 struct intel_fbc *fbc = &dev_priv->fbc;
369 trace_intel_fbc_activate(fbc->crtc);
372 fbc->activated = true;
374 if (INTEL_GEN(dev_priv) >= 7)
375 gen7_fbc_activate(dev_priv);
376 else if (INTEL_GEN(dev_priv) >= 5)
377 ilk_fbc_activate(dev_priv);
378 else if (IS_GM45(dev_priv))
379 g4x_fbc_activate(dev_priv);
381 i8xx_fbc_activate(dev_priv);
384 static void intel_fbc_hw_deactivate(struct drm_i915_private *dev_priv)
386 struct intel_fbc *fbc = &dev_priv->fbc;
388 trace_intel_fbc_deactivate(fbc->crtc);
392 if (INTEL_GEN(dev_priv) >= 5)
393 ilk_fbc_deactivate(dev_priv);
394 else if (IS_GM45(dev_priv))
395 g4x_fbc_deactivate(dev_priv);
397 i8xx_fbc_deactivate(dev_priv);
401 * intel_fbc_is_active - Is FBC active?
402 * @dev_priv: i915 device instance
404 * This function is used to verify the current state of FBC.
406 * FIXME: This should be tracked in the plane config eventually
407 * instead of queried at runtime for most callers.
409 bool intel_fbc_is_active(struct drm_i915_private *dev_priv)
411 return dev_priv->fbc.active;
414 static void intel_fbc_deactivate(struct drm_i915_private *dev_priv,
417 struct intel_fbc *fbc = &dev_priv->fbc;
419 drm_WARN_ON(&dev_priv->drm, !mutex_is_locked(&fbc->lock));
422 intel_fbc_hw_deactivate(dev_priv);
424 fbc->no_fbc_reason = reason;
427 static u64 intel_fbc_cfb_base_max(struct drm_i915_private *i915)
429 if (INTEL_GEN(i915) >= 5 || IS_G4X(i915))
435 static int find_compression_threshold(struct drm_i915_private *dev_priv,
436 struct drm_mm_node *node,
440 int compression_threshold = 1;
444 /* The FBC hardware for BDW/SKL doesn't have access to the stolen
445 * reserved range size, so it always assumes the maximum (8mb) is used.
446 * If we enable FBC using a CFB on that memory range we'll get FIFO
447 * underruns, even if that range is not reserved by the BIOS. */
448 if (IS_BROADWELL(dev_priv) || IS_GEN9_BC(dev_priv))
449 end = resource_size(&dev_priv->dsm) - 8 * 1024 * 1024;
453 end = min(end, intel_fbc_cfb_base_max(dev_priv));
455 /* HACK: This code depends on what we will do in *_enable_fbc. If that
456 * code changes, this code needs to change as well.
458 * The enable_fbc code will attempt to use one of our 2 compression
459 * thresholds, therefore, in that case, we only have 1 resort.
462 /* Try to over-allocate to reduce reallocations and fragmentation. */
463 ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1,
466 return compression_threshold;
469 /* HW's ability to limit the CFB is 1:4 */
470 if (compression_threshold > 4 ||
471 (fb_cpp == 2 && compression_threshold == 2))
474 ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1,
476 if (ret && INTEL_GEN(dev_priv) <= 4) {
479 compression_threshold <<= 1;
482 return compression_threshold;
486 static int intel_fbc_alloc_cfb(struct drm_i915_private *dev_priv,
487 unsigned int size, unsigned int fb_cpp)
489 struct intel_fbc *fbc = &dev_priv->fbc;
490 struct drm_mm_node *compressed_llb;
493 drm_WARN_ON(&dev_priv->drm,
494 drm_mm_node_allocated(&fbc->compressed_fb));
496 ret = find_compression_threshold(dev_priv, &fbc->compressed_fb,
501 drm_info_once(&dev_priv->drm,
502 "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");
505 fbc->threshold = ret;
507 if (INTEL_GEN(dev_priv) >= 5)
508 intel_de_write(dev_priv, ILK_DPFC_CB_BASE,
509 fbc->compressed_fb.start);
510 else if (IS_GM45(dev_priv)) {
511 intel_de_write(dev_priv, DPFC_CB_BASE,
512 fbc->compressed_fb.start);
514 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
518 ret = i915_gem_stolen_insert_node(dev_priv, compressed_llb,
523 fbc->compressed_llb = compressed_llb;
525 GEM_BUG_ON(range_overflows_end_t(u64, dev_priv->dsm.start,
526 fbc->compressed_fb.start,
528 GEM_BUG_ON(range_overflows_end_t(u64, dev_priv->dsm.start,
529 fbc->compressed_llb->start,
531 intel_de_write(dev_priv, FBC_CFB_BASE,
532 dev_priv->dsm.start + fbc->compressed_fb.start);
533 intel_de_write(dev_priv, FBC_LL_BASE,
534 dev_priv->dsm.start + compressed_llb->start);
537 drm_dbg_kms(&dev_priv->drm,
538 "reserved %llu bytes of contiguous stolen space for FBC, threshold: %d\n",
539 fbc->compressed_fb.size, fbc->threshold);
544 kfree(compressed_llb);
545 i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
547 if (drm_mm_initialized(&dev_priv->mm.stolen))
548 drm_info_once(&dev_priv->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);
552 static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
554 struct intel_fbc *fbc = &dev_priv->fbc;
556 if (WARN_ON(intel_fbc_hw_is_active(dev_priv)))
559 if (!drm_mm_node_allocated(&fbc->compressed_fb))
562 if (fbc->compressed_llb) {
563 i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb);
564 kfree(fbc->compressed_llb);
567 i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
570 void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
572 struct intel_fbc *fbc = &dev_priv->fbc;
574 if (!HAS_FBC(dev_priv))
577 mutex_lock(&fbc->lock);
578 __intel_fbc_cleanup_cfb(dev_priv);
579 mutex_unlock(&fbc->lock);
582 static bool stride_is_valid(struct drm_i915_private *dev_priv,
583 u64 modifier, unsigned int stride)
585 /* This should have been caught earlier. */
586 if (drm_WARN_ON_ONCE(&dev_priv->drm, (stride & (64 - 1)) != 0))
589 /* Below are the additional FBC restrictions. */
593 if (IS_GEN(dev_priv, 2) || IS_GEN(dev_priv, 3))
594 return stride == 4096 || stride == 8192;
596 if (IS_GEN(dev_priv, 4) && !IS_G4X(dev_priv) && stride < 2048)
599 /* Display WA #1105: skl,bxt,kbl,cfl,glk */
600 if (IS_GEN(dev_priv, 9) &&
601 modifier == DRM_FORMAT_MOD_LINEAR && stride & 511)
610 static bool pixel_format_is_valid(struct drm_i915_private *dev_priv,
613 switch (pixel_format) {
614 case DRM_FORMAT_XRGB8888:
615 case DRM_FORMAT_XBGR8888:
617 case DRM_FORMAT_XRGB1555:
618 case DRM_FORMAT_RGB565:
619 /* 16bpp not supported on gen2 */
620 if (IS_GEN(dev_priv, 2))
622 /* WaFbcOnly1to1Ratio:ctg */
623 if (IS_G4X(dev_priv))
631 static bool rotation_is_valid(struct drm_i915_private *dev_priv,
632 u32 pixel_format, unsigned int rotation)
634 if (INTEL_GEN(dev_priv) >= 9 && pixel_format == DRM_FORMAT_RGB565 &&
635 drm_rotation_90_or_270(rotation))
637 else if (INTEL_GEN(dev_priv) <= 4 && !IS_G4X(dev_priv) &&
638 rotation != DRM_MODE_ROTATE_0)
645 * For some reason, the hardware tracking starts looking at whatever we
646 * programmed as the display plane base address register. It does not look at
647 * the X and Y offset registers. That's why we include the src x/y offsets
648 * instead of just looking at the plane size.
650 static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc)
652 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
653 struct intel_fbc *fbc = &dev_priv->fbc;
654 unsigned int effective_w, effective_h, max_w, max_h;
656 if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) {
659 } else if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv)) {
662 } else if (IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
670 intel_fbc_get_plane_source_size(&fbc->state_cache, &effective_w,
672 effective_w += fbc->state_cache.plane.adjusted_x;
673 effective_h += fbc->state_cache.plane.adjusted_y;
675 return effective_w <= max_w && effective_h <= max_h;
678 static bool tiling_is_valid(struct drm_i915_private *dev_priv,
682 case DRM_FORMAT_MOD_LINEAR:
683 if (INTEL_GEN(dev_priv) >= 9)
686 case I915_FORMAT_MOD_X_TILED:
687 case I915_FORMAT_MOD_Y_TILED:
694 static void intel_fbc_update_state_cache(struct intel_crtc *crtc,
695 const struct intel_crtc_state *crtc_state,
696 const struct intel_plane_state *plane_state)
698 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
699 struct intel_fbc *fbc = &dev_priv->fbc;
700 struct intel_fbc_state_cache *cache = &fbc->state_cache;
701 struct drm_framebuffer *fb = plane_state->hw.fb;
703 cache->plane.visible = plane_state->uapi.visible;
704 if (!cache->plane.visible)
707 cache->crtc.mode_flags = crtc_state->hw.adjusted_mode.flags;
708 if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
709 cache->crtc.hsw_bdw_pixel_rate = crtc_state->pixel_rate;
711 cache->plane.rotation = plane_state->hw.rotation;
713 * Src coordinates are already rotated by 270 degrees for
714 * the 90/270 degree plane rotation cases (to match the
715 * GTT mapping), hence no need to account for rotation here.
717 cache->plane.src_w = drm_rect_width(&plane_state->uapi.src) >> 16;
718 cache->plane.src_h = drm_rect_height(&plane_state->uapi.src) >> 16;
719 cache->plane.adjusted_x = plane_state->color_plane[0].x;
720 cache->plane.adjusted_y = plane_state->color_plane[0].y;
722 cache->plane.pixel_blend_mode = plane_state->hw.pixel_blend_mode;
724 cache->fb.format = fb->format;
725 cache->fb.modifier = fb->modifier;
727 /* FIXME is this correct? */
728 cache->fb.stride = plane_state->color_plane[0].stride;
729 if (drm_rotation_90_or_270(plane_state->hw.rotation))
730 cache->fb.stride *= fb->format->cpp[0];
732 /* FBC1 compression interval: arbitrary choice of 1 second */
733 cache->interval = drm_mode_vrefresh(&crtc_state->hw.adjusted_mode);
735 cache->fence_y_offset = intel_plane_fence_y_offset(plane_state);
737 drm_WARN_ON(&dev_priv->drm, plane_state->flags & PLANE_HAS_FENCE &&
738 !plane_state->vma->fence);
740 if (plane_state->flags & PLANE_HAS_FENCE &&
741 plane_state->vma->fence)
742 cache->fence_id = plane_state->vma->fence->id;
744 cache->fence_id = -1;
746 cache->psr2_active = crtc_state->has_psr2;
749 static bool intel_fbc_cfb_size_changed(struct drm_i915_private *dev_priv)
751 struct intel_fbc *fbc = &dev_priv->fbc;
753 return intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache) >
754 fbc->compressed_fb.size * fbc->threshold;
757 static u16 intel_fbc_gen9_wa_cfb_stride(struct drm_i915_private *dev_priv)
759 struct intel_fbc *fbc = &dev_priv->fbc;
760 struct intel_fbc_state_cache *cache = &fbc->state_cache;
762 if ((IS_GEN9_BC(dev_priv) || IS_BROXTON(dev_priv)) &&
763 cache->fb.modifier != I915_FORMAT_MOD_X_TILED)
764 return DIV_ROUND_UP(cache->plane.src_w, 32 * fbc->threshold) * 8;
769 static bool intel_fbc_gen9_wa_cfb_stride_changed(struct drm_i915_private *dev_priv)
771 struct intel_fbc *fbc = &dev_priv->fbc;
773 return fbc->params.gen9_wa_cfb_stride != intel_fbc_gen9_wa_cfb_stride(dev_priv);
776 static bool intel_fbc_can_enable(struct drm_i915_private *dev_priv)
778 struct intel_fbc *fbc = &dev_priv->fbc;
780 if (intel_vgpu_active(dev_priv)) {
781 fbc->no_fbc_reason = "VGPU is active";
785 if (!dev_priv->params.enable_fbc) {
786 fbc->no_fbc_reason = "disabled per module param or by default";
790 if (fbc->underrun_detected) {
791 fbc->no_fbc_reason = "underrun detected";
798 static bool intel_fbc_can_activate(struct intel_crtc *crtc)
800 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
801 struct intel_fbc *fbc = &dev_priv->fbc;
802 struct intel_fbc_state_cache *cache = &fbc->state_cache;
804 if (!intel_fbc_can_enable(dev_priv))
807 if (!cache->plane.visible) {
808 fbc->no_fbc_reason = "primary plane not visible";
812 /* We don't need to use a state cache here since this information is
813 * global for all CRTC.
815 if (fbc->underrun_detected) {
816 fbc->no_fbc_reason = "underrun detected";
820 if (cache->crtc.mode_flags & DRM_MODE_FLAG_INTERLACE) {
821 fbc->no_fbc_reason = "incompatible mode";
825 if (!intel_fbc_hw_tracking_covers_screen(crtc)) {
826 fbc->no_fbc_reason = "mode too large for compression";
830 /* The use of a CPU fence is one of two ways to detect writes by the
831 * CPU to the scanout and trigger updates to the FBC.
833 * The other method is by software tracking (see
834 * intel_fbc_invalidate/flush()), it will manually notify FBC and nuke
835 * the current compressed buffer and recompress it.
837 * Note that is possible for a tiled surface to be unmappable (and
838 * so have no fence associated with it) due to aperture constraints
839 * at the time of pinning.
841 * FIXME with 90/270 degree rotation we should use the fence on
842 * the normal GTT view (the rotated view doesn't even have a
843 * fence). Would need changes to the FBC fence Y offset as well.
844 * For now this will effectively disable FBC with 90/270 degree
847 if (INTEL_GEN(dev_priv) < 9 && cache->fence_id < 0) {
848 fbc->no_fbc_reason = "framebuffer not tiled or fenced";
852 if (!pixel_format_is_valid(dev_priv, cache->fb.format->format)) {
853 fbc->no_fbc_reason = "pixel format is invalid";
857 if (!rotation_is_valid(dev_priv, cache->fb.format->format,
858 cache->plane.rotation)) {
859 fbc->no_fbc_reason = "rotation unsupported";
863 if (!tiling_is_valid(dev_priv, cache->fb.modifier)) {
864 fbc->no_fbc_reason = "tiling unsupported";
868 if (!stride_is_valid(dev_priv, cache->fb.modifier, cache->fb.stride)) {
869 fbc->no_fbc_reason = "framebuffer stride not supported";
873 if (cache->plane.pixel_blend_mode != DRM_MODE_BLEND_PIXEL_NONE &&
874 cache->fb.format->has_alpha) {
875 fbc->no_fbc_reason = "per-pixel alpha blending is incompatible with FBC";
879 /* WaFbcExceedCdClockThreshold:hsw,bdw */
880 if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
881 cache->crtc.hsw_bdw_pixel_rate >= dev_priv->cdclk.hw.cdclk * 95 / 100) {
882 fbc->no_fbc_reason = "pixel rate is too big";
886 /* It is possible for the required CFB size change without a
887 * crtc->disable + crtc->enable since it is possible to change the
888 * stride without triggering a full modeset. Since we try to
889 * over-allocate the CFB, there's a chance we may keep FBC enabled even
890 * if this happens, but if we exceed the current CFB size we'll have to
891 * disable FBC. Notice that it would be possible to disable FBC, wait
892 * for a frame, free the stolen node, then try to reenable FBC in case
893 * we didn't get any invalidate/deactivate calls, but this would require
894 * a lot of tracking just for a specific case. If we conclude it's an
895 * important case, we can implement it later. */
896 if (intel_fbc_cfb_size_changed(dev_priv)) {
897 fbc->no_fbc_reason = "CFB requirements changed";
902 * Work around a problem on GEN9+ HW, where enabling FBC on a plane
903 * having a Y offset that isn't divisible by 4 causes FIFO underrun
904 * and screen flicker.
906 if (INTEL_GEN(dev_priv) >= 9 &&
907 (fbc->state_cache.plane.adjusted_y & 3)) {
908 fbc->no_fbc_reason = "plane Y offset is misaligned";
912 /* Wa_22010751166: icl, ehl, tgl, dg1, rkl */
913 if (INTEL_GEN(dev_priv) >= 11 &&
914 (cache->plane.src_h + cache->plane.adjusted_y) % 4) {
915 fbc->no_fbc_reason = "plane height + offset is non-modulo of 4";
920 * Tigerlake is not supporting FBC with PSR2.
921 * Recommendation is to keep this combination disabled
922 * Bspec: 50422 HSD: 14010260002
924 if (fbc->state_cache.psr2_active && IS_TIGERLAKE(dev_priv)) {
925 fbc->no_fbc_reason = "not supported with PSR2";
932 static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
933 struct intel_fbc_reg_params *params)
935 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
936 struct intel_fbc *fbc = &dev_priv->fbc;
937 struct intel_fbc_state_cache *cache = &fbc->state_cache;
939 /* Since all our fields are integer types, use memset here so the
940 * comparison function can rely on memcmp because the padding will be
942 memset(params, 0, sizeof(*params));
944 params->fence_id = cache->fence_id;
945 params->fence_y_offset = cache->fence_y_offset;
947 params->interval = cache->interval;
949 params->crtc.pipe = crtc->pipe;
950 params->crtc.i9xx_plane = to_intel_plane(crtc->base.primary)->i9xx_plane;
952 params->fb.format = cache->fb.format;
953 params->fb.modifier = cache->fb.modifier;
954 params->fb.stride = cache->fb.stride;
956 params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);
958 params->gen9_wa_cfb_stride = cache->gen9_wa_cfb_stride;
960 params->plane_visible = cache->plane.visible;
963 static bool intel_fbc_can_flip_nuke(const struct intel_crtc_state *crtc_state)
965 struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
966 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
967 const struct intel_fbc *fbc = &dev_priv->fbc;
968 const struct intel_fbc_state_cache *cache = &fbc->state_cache;
969 const struct intel_fbc_reg_params *params = &fbc->params;
971 if (drm_atomic_crtc_needs_modeset(&crtc_state->uapi))
974 if (!params->plane_visible)
977 if (!intel_fbc_can_activate(crtc))
980 if (params->fb.format != cache->fb.format)
983 if (params->fb.modifier != cache->fb.modifier)
986 if (params->fb.stride != cache->fb.stride)
989 if (params->cfb_size != intel_fbc_calculate_cfb_size(dev_priv, cache))
992 if (params->gen9_wa_cfb_stride != cache->gen9_wa_cfb_stride)
998 bool intel_fbc_pre_update(struct intel_atomic_state *state,
999 struct intel_crtc *crtc)
1001 struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1002 const struct intel_crtc_state *crtc_state =
1003 intel_atomic_get_new_crtc_state(state, crtc);
1004 const struct intel_plane_state *plane_state =
1005 intel_atomic_get_new_plane_state(state, plane);
1006 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1007 struct intel_fbc *fbc = &dev_priv->fbc;
1008 const char *reason = "update pending";
1009 bool need_vblank_wait = false;
1011 if (!plane->has_fbc || !plane_state)
1012 return need_vblank_wait;
1014 mutex_lock(&fbc->lock);
1016 if (fbc->crtc != crtc)
1019 intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
1020 fbc->flip_pending = true;
1022 if (!intel_fbc_can_flip_nuke(crtc_state)) {
1023 intel_fbc_deactivate(dev_priv, reason);
1026 * Display WA #1198: glk+
1027 * Need an extra vblank wait between FBC disable and most plane
1028 * updates. Bspec says this is only needed for plane disable, but
1029 * that is not true. Touching most plane registers will cause the
1030 * corruption to appear. Also SKL/derivatives do not seem to be
1033 * TODO: could optimize this a bit by sampling the frame
1034 * counter when we disable FBC (if it was already done earlier)
1035 * and skipping the extra vblank wait before the plane update
1036 * if at least one frame has already passed.
1038 if (fbc->activated &&
1039 (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)))
1040 need_vblank_wait = true;
1041 fbc->activated = false;
1044 mutex_unlock(&fbc->lock);
1046 return need_vblank_wait;
1050 * __intel_fbc_disable - disable FBC
1051 * @dev_priv: i915 device instance
1053 * This is the low level function that actually disables FBC. Callers should
1054 * grab the FBC lock.
1056 static void __intel_fbc_disable(struct drm_i915_private *dev_priv)
1058 struct intel_fbc *fbc = &dev_priv->fbc;
1059 struct intel_crtc *crtc = fbc->crtc;
1061 drm_WARN_ON(&dev_priv->drm, !mutex_is_locked(&fbc->lock));
1062 drm_WARN_ON(&dev_priv->drm, !fbc->crtc);
1063 drm_WARN_ON(&dev_priv->drm, fbc->active);
1065 drm_dbg_kms(&dev_priv->drm, "Disabling FBC on pipe %c\n",
1066 pipe_name(crtc->pipe));
1068 __intel_fbc_cleanup_cfb(dev_priv);
1073 static void __intel_fbc_post_update(struct intel_crtc *crtc)
1075 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1076 struct intel_fbc *fbc = &dev_priv->fbc;
1078 drm_WARN_ON(&dev_priv->drm, !mutex_is_locked(&fbc->lock));
1080 if (fbc->crtc != crtc)
1083 fbc->flip_pending = false;
1085 if (!dev_priv->params.enable_fbc) {
1086 intel_fbc_deactivate(dev_priv, "disabled at runtime per module param");
1087 __intel_fbc_disable(dev_priv);
1092 intel_fbc_get_reg_params(crtc, &fbc->params);
1094 if (!intel_fbc_can_activate(crtc))
1097 if (!fbc->busy_bits)
1098 intel_fbc_hw_activate(dev_priv);
1100 intel_fbc_deactivate(dev_priv, "frontbuffer write");
1103 void intel_fbc_post_update(struct intel_atomic_state *state,
1104 struct intel_crtc *crtc)
1106 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1107 struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1108 const struct intel_plane_state *plane_state =
1109 intel_atomic_get_new_plane_state(state, plane);
1110 struct intel_fbc *fbc = &dev_priv->fbc;
1112 if (!plane->has_fbc || !plane_state)
1115 mutex_lock(&fbc->lock);
1116 __intel_fbc_post_update(crtc);
1117 mutex_unlock(&fbc->lock);
1120 static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
1123 return to_intel_plane(fbc->crtc->base.primary)->frontbuffer_bit;
1125 return fbc->possible_framebuffer_bits;
1128 void intel_fbc_invalidate(struct drm_i915_private *dev_priv,
1129 unsigned int frontbuffer_bits,
1130 enum fb_op_origin origin)
1132 struct intel_fbc *fbc = &dev_priv->fbc;
1134 if (!HAS_FBC(dev_priv))
1137 if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
1140 mutex_lock(&fbc->lock);
1142 fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
1144 if (fbc->crtc && fbc->busy_bits)
1145 intel_fbc_deactivate(dev_priv, "frontbuffer write");
1147 mutex_unlock(&fbc->lock);
1150 void intel_fbc_flush(struct drm_i915_private *dev_priv,
1151 unsigned int frontbuffer_bits, enum fb_op_origin origin)
1153 struct intel_fbc *fbc = &dev_priv->fbc;
1155 if (!HAS_FBC(dev_priv))
1159 * GTT tracking does not nuke the entire cfb
1160 * so don't clear busy_bits set for some other
1163 if (origin == ORIGIN_GTT)
1166 mutex_lock(&fbc->lock);
1168 fbc->busy_bits &= ~frontbuffer_bits;
1170 if (origin == ORIGIN_FLIP)
1173 if (!fbc->busy_bits && fbc->crtc &&
1174 (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
1176 intel_fbc_recompress(dev_priv);
1177 else if (!fbc->flip_pending)
1178 __intel_fbc_post_update(fbc->crtc);
1182 mutex_unlock(&fbc->lock);
1186 * intel_fbc_choose_crtc - select a CRTC to enable FBC on
1187 * @dev_priv: i915 device instance
1188 * @state: the atomic state structure
1190 * This function looks at the proposed state for CRTCs and planes, then chooses
1191 * which pipe is going to have FBC by setting intel_crtc_state->enable_fbc to
1194 * Later, intel_fbc_enable is going to look for state->enable_fbc and then maybe
1195 * enable FBC for the chosen CRTC. If it does, it will set dev_priv->fbc.crtc.
1197 void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv,
1198 struct intel_atomic_state *state)
1200 struct intel_fbc *fbc = &dev_priv->fbc;
1201 struct intel_plane *plane;
1202 struct intel_plane_state *plane_state;
1203 bool crtc_chosen = false;
1206 mutex_lock(&fbc->lock);
1208 /* Does this atomic commit involve the CRTC currently tied to FBC? */
1210 !intel_atomic_get_new_crtc_state(state, fbc->crtc))
1213 if (!intel_fbc_can_enable(dev_priv))
1216 /* Simply choose the first CRTC that is compatible and has a visible
1217 * plane. We could go for fancier schemes such as checking the plane
1218 * size, but this would just affect the few platforms that don't tie FBC
1219 * to pipe or plane A. */
1220 for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1221 struct intel_crtc_state *crtc_state;
1222 struct intel_crtc *crtc = to_intel_crtc(plane_state->hw.crtc);
1224 if (!plane->has_fbc)
1227 if (!plane_state->uapi.visible)
1230 crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
1232 crtc_state->enable_fbc = true;
1238 fbc->no_fbc_reason = "no suitable CRTC for FBC";
1241 mutex_unlock(&fbc->lock);
1245 * intel_fbc_enable: tries to enable FBC on the CRTC
1247 * @state: corresponding &drm_crtc_state for @crtc
1249 * This function checks if the given CRTC was chosen for FBC, then enables it if
1250 * possible. Notice that it doesn't activate FBC. It is valid to call
1251 * intel_fbc_enable multiple times for the same pipe without an
1252 * intel_fbc_disable in the middle, as long as it is deactivated.
1254 void intel_fbc_enable(struct intel_atomic_state *state,
1255 struct intel_crtc *crtc)
1257 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1258 struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1259 const struct intel_crtc_state *crtc_state =
1260 intel_atomic_get_new_crtc_state(state, crtc);
1261 const struct intel_plane_state *plane_state =
1262 intel_atomic_get_new_plane_state(state, plane);
1263 struct intel_fbc *fbc = &dev_priv->fbc;
1264 struct intel_fbc_state_cache *cache = &fbc->state_cache;
1266 if (!plane->has_fbc || !plane_state)
1269 mutex_lock(&fbc->lock);
1272 if (fbc->crtc != crtc ||
1273 (!intel_fbc_cfb_size_changed(dev_priv) &&
1274 !intel_fbc_gen9_wa_cfb_stride_changed(dev_priv)))
1277 __intel_fbc_disable(dev_priv);
1280 drm_WARN_ON(&dev_priv->drm, fbc->active);
1282 intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
1284 /* FIXME crtc_state->enable_fbc lies :( */
1285 if (!cache->plane.visible)
1288 if (intel_fbc_alloc_cfb(dev_priv,
1289 intel_fbc_calculate_cfb_size(dev_priv, cache),
1290 plane_state->hw.fb->format->cpp[0])) {
1291 cache->plane.visible = false;
1292 fbc->no_fbc_reason = "not enough stolen memory";
1296 cache->gen9_wa_cfb_stride = intel_fbc_gen9_wa_cfb_stride(dev_priv);
1298 drm_dbg_kms(&dev_priv->drm, "Enabling FBC on pipe %c\n",
1299 pipe_name(crtc->pipe));
1300 fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1304 mutex_unlock(&fbc->lock);
1308 * intel_fbc_disable - disable FBC if it's associated with crtc
1311 * This function disables FBC if it's associated with the provided CRTC.
1313 void intel_fbc_disable(struct intel_crtc *crtc)
1315 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1316 struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1317 struct intel_fbc *fbc = &dev_priv->fbc;
1319 if (!plane->has_fbc)
1322 mutex_lock(&fbc->lock);
1323 if (fbc->crtc == crtc)
1324 __intel_fbc_disable(dev_priv);
1325 mutex_unlock(&fbc->lock);
1329 * intel_fbc_global_disable - globally disable FBC
1330 * @dev_priv: i915 device instance
1332 * This function disables FBC regardless of which CRTC is associated with it.
1334 void intel_fbc_global_disable(struct drm_i915_private *dev_priv)
1336 struct intel_fbc *fbc = &dev_priv->fbc;
1338 if (!HAS_FBC(dev_priv))
1341 mutex_lock(&fbc->lock);
1343 drm_WARN_ON(&dev_priv->drm, fbc->crtc->active);
1344 __intel_fbc_disable(dev_priv);
1346 mutex_unlock(&fbc->lock);
1349 static void intel_fbc_underrun_work_fn(struct work_struct *work)
1351 struct drm_i915_private *dev_priv =
1352 container_of(work, struct drm_i915_private, fbc.underrun_work);
1353 struct intel_fbc *fbc = &dev_priv->fbc;
1355 mutex_lock(&fbc->lock);
1357 /* Maybe we were scheduled twice. */
1358 if (fbc->underrun_detected || !fbc->crtc)
1361 drm_dbg_kms(&dev_priv->drm, "Disabling FBC due to FIFO underrun.\n");
1362 fbc->underrun_detected = true;
1364 intel_fbc_deactivate(dev_priv, "FIFO underrun");
1366 mutex_unlock(&fbc->lock);
1370 * intel_fbc_reset_underrun - reset FBC fifo underrun status.
1371 * @dev_priv: i915 device instance
1373 * See intel_fbc_handle_fifo_underrun_irq(). For automated testing we
1374 * want to re-enable FBC after an underrun to increase test coverage.
1376 int intel_fbc_reset_underrun(struct drm_i915_private *dev_priv)
1380 cancel_work_sync(&dev_priv->fbc.underrun_work);
1382 ret = mutex_lock_interruptible(&dev_priv->fbc.lock);
1386 if (dev_priv->fbc.underrun_detected) {
1387 drm_dbg_kms(&dev_priv->drm,
1388 "Re-allowing FBC after fifo underrun\n");
1389 dev_priv->fbc.no_fbc_reason = "FIFO underrun cleared";
1392 dev_priv->fbc.underrun_detected = false;
1393 mutex_unlock(&dev_priv->fbc.lock);
1399 * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
1400 * @dev_priv: i915 device instance
1402 * Without FBC, most underruns are harmless and don't really cause too many
1403 * problems, except for an annoying message on dmesg. With FBC, underruns can
1404 * become black screens or even worse, especially when paired with bad
1405 * watermarks. So in order for us to be on the safe side, completely disable FBC
1406 * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
1407 * already suggests that watermarks may be bad, so try to be as safe as
1410 * This function is called from the IRQ handler.
1412 void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv)
1414 struct intel_fbc *fbc = &dev_priv->fbc;
1416 if (!HAS_FBC(dev_priv))
1419 /* There's no guarantee that underrun_detected won't be set to true
1420 * right after this check and before the work is scheduled, but that's
1421 * not a problem since we'll check it again under the work function
1422 * while FBC is locked. This check here is just to prevent us from
1423 * unnecessarily scheduling the work, and it relies on the fact that we
1424 * never switch underrun_detect back to false after it's true. */
1425 if (READ_ONCE(fbc->underrun_detected))
1428 schedule_work(&fbc->underrun_work);
1432 * The DDX driver changes its behavior depending on the value it reads from
1433 * i915.enable_fbc, so sanitize it by translating the default value into either
1434 * 0 or 1 in order to allow it to know what's going on.
1436 * Notice that this is done at driver initialization and we still allow user
1437 * space to change the value during runtime without sanitizing it again. IGT
1438 * relies on being able to change i915.enable_fbc at runtime.
1440 static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv)
1442 if (dev_priv->params.enable_fbc >= 0)
1443 return !!dev_priv->params.enable_fbc;
1445 if (!HAS_FBC(dev_priv))
1448 if (IS_BROADWELL(dev_priv) || INTEL_GEN(dev_priv) >= 9)
1454 static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv)
1456 /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
1457 if (intel_vtd_active() &&
1458 (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) {
1459 drm_info(&dev_priv->drm,
1460 "Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
1468 * intel_fbc_init - Initialize FBC
1469 * @dev_priv: the i915 device
1471 * This function might be called during PM init process.
1473 void intel_fbc_init(struct drm_i915_private *dev_priv)
1475 struct intel_fbc *fbc = &dev_priv->fbc;
1477 INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
1478 mutex_init(&fbc->lock);
1479 fbc->active = false;
1481 if (!drm_mm_initialized(&dev_priv->mm.stolen))
1482 mkwrite_device_info(dev_priv)->display.has_fbc = false;
1484 if (need_fbc_vtd_wa(dev_priv))
1485 mkwrite_device_info(dev_priv)->display.has_fbc = false;
1487 dev_priv->params.enable_fbc = intel_sanitize_fbc_option(dev_priv);
1488 drm_dbg_kms(&dev_priv->drm, "Sanitized enable_fbc value: %d\n",
1489 dev_priv->params.enable_fbc);
1491 if (!HAS_FBC(dev_priv)) {
1492 fbc->no_fbc_reason = "unsupported by this chipset";
1496 /* We still don't have any sort of hardware state readout for FBC, so
1497 * deactivate it in case the BIOS activated it to make sure software
1498 * matches the hardware state. */
1499 if (intel_fbc_hw_is_active(dev_priv))
1500 intel_fbc_hw_deactivate(dev_priv);