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v4.6
   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
  21 * DEALINGS IN THE SOFTWARE.
  22 */
  23
  24/**
  25 * DOC: Frame Buffer Compression (FBC)
  26 *
  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.
  30 *
  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.
  34 *
  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.
  39 */
  40
  41#include "intel_drv.h"
  42#include "i915_drv.h"
  43
  44static inline bool fbc_supported(struct drm_i915_private *dev_priv)
  45{
  46	return HAS_FBC(dev_priv);
  47}
  48
  49static inline bool fbc_on_pipe_a_only(struct drm_i915_private *dev_priv)
  50{
  51	return IS_HASWELL(dev_priv) || INTEL_INFO(dev_priv)->gen >= 8;
  52}
  53
  54static inline bool fbc_on_plane_a_only(struct drm_i915_private *dev_priv)
  55{
  56	return INTEL_INFO(dev_priv)->gen < 4;
  57}
  58
  59static inline bool no_fbc_on_multiple_pipes(struct drm_i915_private *dev_priv)
  60{
  61	return INTEL_INFO(dev_priv)->gen <= 3;
  62}
  63
  64/*
  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.
  71 */
  72static unsigned int get_crtc_fence_y_offset(struct intel_crtc *crtc)
  73{
  74	return crtc->base.y - crtc->adjusted_y;
  75}
  76
  77/*
  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.
  81 */
  82static void intel_fbc_get_plane_source_size(struct intel_fbc_state_cache *cache,
  83					    int *width, int *height)
  84{
  85	int w, h;
  86
  87	if (intel_rotation_90_or_270(cache->plane.rotation)) {
  88		w = cache->plane.src_h;
  89		h = cache->plane.src_w;
  90	} else {
  91		w = cache->plane.src_w;
  92		h = cache->plane.src_h;
  93	}
  94
  95	if (width)
  96		*width = w;
  97	if (height)
  98		*height = h;
  99}
 100
 101static int intel_fbc_calculate_cfb_size(struct drm_i915_private *dev_priv,
 102					struct intel_fbc_state_cache *cache)
 103{
 104	int lines;
 105
 106	intel_fbc_get_plane_source_size(cache, NULL, &lines);
 107	if (INTEL_INFO(dev_priv)->gen >= 7)
 108		lines = min(lines, 2048);
 
 
 109
 110	/* Hardware needs the full buffer stride, not just the active area. */
 111	return lines * cache->fb.stride;
 112}
 113
 114static void i8xx_fbc_deactivate(struct drm_i915_private *dev_priv)
 115{
 116	u32 fbc_ctl;
 117
 118	/* Disable compression */
 119	fbc_ctl = I915_READ(FBC_CONTROL);
 120	if ((fbc_ctl & FBC_CTL_EN) == 0)
 121		return;
 122
 123	fbc_ctl &= ~FBC_CTL_EN;
 124	I915_WRITE(FBC_CONTROL, fbc_ctl);
 125
 126	/* Wait for compressing bit to clear */
 127	if (wait_for((I915_READ(FBC_STATUS) & FBC_STAT_COMPRESSING) == 0, 10)) {
 
 
 128		DRM_DEBUG_KMS("FBC idle timed out\n");
 129		return;
 130	}
 131}
 132
 133static void i8xx_fbc_activate(struct drm_i915_private *dev_priv)
 134{
 135	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 136	int cfb_pitch;
 137	int i;
 138	u32 fbc_ctl;
 139
 140	/* Note: fbc.threshold == 1 for i8xx */
 141	cfb_pitch = params->cfb_size / FBC_LL_SIZE;
 142	if (params->fb.stride < cfb_pitch)
 143		cfb_pitch = params->fb.stride;
 144
 145	/* FBC_CTL wants 32B or 64B units */
 146	if (IS_GEN2(dev_priv))
 147		cfb_pitch = (cfb_pitch / 32) - 1;
 148	else
 149		cfb_pitch = (cfb_pitch / 64) - 1;
 150
 151	/* Clear old tags */
 152	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
 153		I915_WRITE(FBC_TAG(i), 0);
 154
 155	if (IS_GEN4(dev_priv)) {
 156		u32 fbc_ctl2;
 157
 158		/* Set it up... */
 159		fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
 160		fbc_ctl2 |= FBC_CTL_PLANE(params->crtc.plane);
 161		I915_WRITE(FBC_CONTROL2, fbc_ctl2);
 162		I915_WRITE(FBC_FENCE_OFF, params->crtc.fence_y_offset);
 163	}
 164
 165	/* enable it... */
 166	fbc_ctl = I915_READ(FBC_CONTROL);
 167	fbc_ctl &= 0x3fff << FBC_CTL_INTERVAL_SHIFT;
 168	fbc_ctl |= FBC_CTL_EN | FBC_CTL_PERIODIC;
 169	if (IS_I945GM(dev_priv))
 170		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
 171	fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
 172	fbc_ctl |= params->fb.fence_reg;
 173	I915_WRITE(FBC_CONTROL, fbc_ctl);
 174}
 175
 176static bool i8xx_fbc_is_active(struct drm_i915_private *dev_priv)
 177{
 178	return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
 179}
 180
 181static void g4x_fbc_activate(struct drm_i915_private *dev_priv)
 182{
 183	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 184	u32 dpfc_ctl;
 185
 186	dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane) | DPFC_SR_EN;
 187	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 188		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 189	else
 190		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 191	dpfc_ctl |= DPFC_CTL_FENCE_EN | params->fb.fence_reg;
 192
 193	I915_WRITE(DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
 
 
 
 
 
 194
 195	/* enable it... */
 196	I915_WRITE(DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 197}
 198
 199static void g4x_fbc_deactivate(struct drm_i915_private *dev_priv)
 200{
 201	u32 dpfc_ctl;
 202
 203	/* Disable compression */
 204	dpfc_ctl = I915_READ(DPFC_CONTROL);
 205	if (dpfc_ctl & DPFC_CTL_EN) {
 206		dpfc_ctl &= ~DPFC_CTL_EN;
 207		I915_WRITE(DPFC_CONTROL, dpfc_ctl);
 208	}
 209}
 210
 211static bool g4x_fbc_is_active(struct drm_i915_private *dev_priv)
 212{
 213	return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
 214}
 215
 216/* This function forces a CFB recompression through the nuke operation. */
 217static void intel_fbc_recompress(struct drm_i915_private *dev_priv)
 218{
 219	I915_WRITE(MSG_FBC_REND_STATE, FBC_REND_NUKE);
 220	POSTING_READ(MSG_FBC_REND_STATE);
 221}
 222
 223static void ilk_fbc_activate(struct drm_i915_private *dev_priv)
 224{
 225	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 226	u32 dpfc_ctl;
 227	int threshold = dev_priv->fbc.threshold;
 228
 229	dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane);
 230	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 231		threshold++;
 232
 233	switch (threshold) {
 234	case 4:
 235	case 3:
 236		dpfc_ctl |= DPFC_CTL_LIMIT_4X;
 237		break;
 238	case 2:
 239		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 240		break;
 241	case 1:
 242		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 243		break;
 244	}
 245	dpfc_ctl |= DPFC_CTL_FENCE_EN;
 246	if (IS_GEN5(dev_priv))
 247		dpfc_ctl |= params->fb.fence_reg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 248
 249	I915_WRITE(ILK_DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
 250	I915_WRITE(ILK_FBC_RT_BASE, params->fb.ggtt_offset | ILK_FBC_RT_VALID);
 
 251	/* enable it... */
 252	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 253
 254	if (IS_GEN6(dev_priv)) {
 255		I915_WRITE(SNB_DPFC_CTL_SA,
 256			   SNB_CPU_FENCE_ENABLE | params->fb.fence_reg);
 257		I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
 258	}
 259
 260	intel_fbc_recompress(dev_priv);
 261}
 262
 263static void ilk_fbc_deactivate(struct drm_i915_private *dev_priv)
 264{
 265	u32 dpfc_ctl;
 266
 267	/* Disable compression */
 268	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
 269	if (dpfc_ctl & DPFC_CTL_EN) {
 270		dpfc_ctl &= ~DPFC_CTL_EN;
 271		I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);
 272	}
 273}
 274
 275static bool ilk_fbc_is_active(struct drm_i915_private *dev_priv)
 276{
 277	return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
 278}
 279
 280static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
 281{
 282	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 283	u32 dpfc_ctl;
 284	int threshold = dev_priv->fbc.threshold;
 285
 286	dpfc_ctl = 0;
 287	if (IS_IVYBRIDGE(dev_priv))
 288		dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.plane);
 289
 290	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 291		threshold++;
 292
 293	switch (threshold) {
 294	case 4:
 295	case 3:
 296		dpfc_ctl |= DPFC_CTL_LIMIT_4X;
 297		break;
 298	case 2:
 299		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 300		break;
 301	case 1:
 302		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 303		break;
 304	}
 305
 306	dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
 
 
 
 
 
 
 
 
 
 307
 308	if (dev_priv->fbc.false_color)
 309		dpfc_ctl |= FBC_CTL_FALSE_COLOR;
 310
 311	if (IS_IVYBRIDGE(dev_priv)) {
 312		/* WaFbcAsynchFlipDisableFbcQueue:ivb */
 313		I915_WRITE(ILK_DISPLAY_CHICKEN1,
 314			   I915_READ(ILK_DISPLAY_CHICKEN1) |
 315			   ILK_FBCQ_DIS);
 316	} else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
 317		/* WaFbcAsynchFlipDisableFbcQueue:hsw,bdw */
 318		I915_WRITE(CHICKEN_PIPESL_1(params->crtc.pipe),
 319			   I915_READ(CHICKEN_PIPESL_1(params->crtc.pipe)) |
 320			   HSW_FBCQ_DIS);
 321	}
 322
 323	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 324
 325	I915_WRITE(SNB_DPFC_CTL_SA,
 326		   SNB_CPU_FENCE_ENABLE | params->fb.fence_reg);
 327	I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
 328
 329	intel_fbc_recompress(dev_priv);
 330}
 331
 332static bool intel_fbc_hw_is_active(struct drm_i915_private *dev_priv)
 333{
 334	if (INTEL_INFO(dev_priv)->gen >= 5)
 335		return ilk_fbc_is_active(dev_priv);
 336	else if (IS_GM45(dev_priv))
 337		return g4x_fbc_is_active(dev_priv);
 338	else
 339		return i8xx_fbc_is_active(dev_priv);
 340}
 341
 342static void intel_fbc_hw_activate(struct drm_i915_private *dev_priv)
 343{
 344	struct intel_fbc *fbc = &dev_priv->fbc;
 345
 346	fbc->active = true;
 347
 348	if (INTEL_INFO(dev_priv)->gen >= 7)
 349		gen7_fbc_activate(dev_priv);
 350	else if (INTEL_INFO(dev_priv)->gen >= 5)
 351		ilk_fbc_activate(dev_priv);
 352	else if (IS_GM45(dev_priv))
 353		g4x_fbc_activate(dev_priv);
 354	else
 355		i8xx_fbc_activate(dev_priv);
 356}
 357
 358static void intel_fbc_hw_deactivate(struct drm_i915_private *dev_priv)
 359{
 360	struct intel_fbc *fbc = &dev_priv->fbc;
 361
 362	fbc->active = false;
 363
 364	if (INTEL_INFO(dev_priv)->gen >= 5)
 365		ilk_fbc_deactivate(dev_priv);
 366	else if (IS_GM45(dev_priv))
 367		g4x_fbc_deactivate(dev_priv);
 368	else
 369		i8xx_fbc_deactivate(dev_priv);
 370}
 371
 372/**
 373 * intel_fbc_is_active - Is FBC active?
 374 * @dev_priv: i915 device instance
 375 *
 376 * This function is used to verify the current state of FBC.
 
 377 * FIXME: This should be tracked in the plane config eventually
 378 *        instead of queried at runtime for most callers.
 379 */
 380bool intel_fbc_is_active(struct drm_i915_private *dev_priv)
 381{
 382	return dev_priv->fbc.active;
 383}
 384
 385static void intel_fbc_work_fn(struct work_struct *__work)
 386{
 387	struct drm_i915_private *dev_priv =
 388		container_of(__work, struct drm_i915_private, fbc.work.work);
 389	struct intel_fbc *fbc = &dev_priv->fbc;
 390	struct intel_fbc_work *work = &fbc->work;
 391	struct intel_crtc *crtc = fbc->crtc;
 392	struct drm_vblank_crtc *vblank = &dev_priv->dev->vblank[crtc->pipe];
 393
 394	if (drm_crtc_vblank_get(&crtc->base)) {
 395		DRM_ERROR("vblank not available for FBC on pipe %c\n",
 396			  pipe_name(crtc->pipe));
 397
 398		mutex_lock(&fbc->lock);
 399		work->scheduled = false;
 400		mutex_unlock(&fbc->lock);
 401		return;
 402	}
 403
 404retry:
 405	/* Delay the actual enabling to let pageflipping cease and the
 406	 * display to settle before starting the compression. Note that
 407	 * this delay also serves a second purpose: it allows for a
 408	 * vblank to pass after disabling the FBC before we attempt
 409	 * to modify the control registers.
 410	 *
 411	 * WaFbcWaitForVBlankBeforeEnable:ilk,snb
 412	 *
 413	 * It is also worth mentioning that since work->scheduled_vblank can be
 414	 * updated multiple times by the other threads, hitting the timeout is
 415	 * not an error condition. We'll just end up hitting the "goto retry"
 416	 * case below.
 417	 */
 418	wait_event_timeout(vblank->queue,
 419		drm_crtc_vblank_count(&crtc->base) != work->scheduled_vblank,
 420		msecs_to_jiffies(50));
 421
 422	mutex_lock(&fbc->lock);
 423
 424	/* Were we cancelled? */
 425	if (!work->scheduled)
 426		goto out;
 427
 428	/* Were we delayed again while this function was sleeping? */
 429	if (drm_crtc_vblank_count(&crtc->base) == work->scheduled_vblank) {
 430		mutex_unlock(&fbc->lock);
 431		goto retry;
 432	}
 433
 434	intel_fbc_hw_activate(dev_priv);
 435
 436	work->scheduled = false;
 437
 438out:
 439	mutex_unlock(&fbc->lock);
 440	drm_crtc_vblank_put(&crtc->base);
 441}
 442
 443static void intel_fbc_schedule_activation(struct intel_crtc *crtc)
 444{
 445	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 446	struct intel_fbc *fbc = &dev_priv->fbc;
 447	struct intel_fbc_work *work = &fbc->work;
 448
 449	WARN_ON(!mutex_is_locked(&fbc->lock));
 450
 451	if (drm_crtc_vblank_get(&crtc->base)) {
 452		DRM_ERROR("vblank not available for FBC on pipe %c\n",
 453			  pipe_name(crtc->pipe));
 454		return;
 455	}
 456
 457	/* It is useless to call intel_fbc_cancel_work() or cancel_work() in
 458	 * this function since we're not releasing fbc.lock, so it won't have an
 459	 * opportunity to grab it to discover that it was cancelled. So we just
 460	 * update the expected jiffy count. */
 461	work->scheduled = true;
 462	work->scheduled_vblank = drm_crtc_vblank_count(&crtc->base);
 463	drm_crtc_vblank_put(&crtc->base);
 464
 465	schedule_work(&work->work);
 466}
 467
 468static void intel_fbc_deactivate(struct drm_i915_private *dev_priv)
 469{
 470	struct intel_fbc *fbc = &dev_priv->fbc;
 471
 472	WARN_ON(!mutex_is_locked(&fbc->lock));
 473
 474	/* Calling cancel_work() here won't help due to the fact that the work
 475	 * function grabs fbc->lock. Just set scheduled to false so the work
 476	 * function can know it was cancelled. */
 477	fbc->work.scheduled = false;
 478
 479	if (fbc->active)
 480		intel_fbc_hw_deactivate(dev_priv);
 481}
 482
 483static bool multiple_pipes_ok(struct intel_crtc *crtc)
 
 484{
 485	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 486	struct drm_plane *primary = crtc->base.primary;
 487	struct intel_fbc *fbc = &dev_priv->fbc;
 488	enum pipe pipe = crtc->pipe;
 489
 490	/* Don't even bother tracking anything we don't need. */
 491	if (!no_fbc_on_multiple_pipes(dev_priv))
 492		return true;
 493
 494	WARN_ON(!drm_modeset_is_locked(&primary->mutex));
 495
 496	if (to_intel_plane_state(primary->state)->visible)
 497		fbc->visible_pipes_mask |= (1 << pipe);
 498	else
 499		fbc->visible_pipes_mask &= ~(1 << pipe);
 500
 501	return (fbc->visible_pipes_mask & ~(1 << pipe)) != 0;
 502}
 503
 504static int find_compression_threshold(struct drm_i915_private *dev_priv,
 505				      struct drm_mm_node *node,
 506				      int size,
 507				      int fb_cpp)
 508{
 
 509	int compression_threshold = 1;
 510	int ret;
 511	u64 end;
 512
 513	/* The FBC hardware for BDW/SKL doesn't have access to the stolen
 514	 * reserved range size, so it always assumes the maximum (8mb) is used.
 515	 * If we enable FBC using a CFB on that memory range we'll get FIFO
 516	 * underruns, even if that range is not reserved by the BIOS. */
 517	if (IS_BROADWELL(dev_priv) ||
 518	    IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv))
 519		end = dev_priv->gtt.stolen_size - 8 * 1024 * 1024;
 520	else
 521		end = dev_priv->gtt.stolen_usable_size;
 522
 523	/* HACK: This code depends on what we will do in *_enable_fbc. If that
 524	 * code changes, this code needs to change as well.
 525	 *
 526	 * The enable_fbc code will attempt to use one of our 2 compression
 527	 * thresholds, therefore, in that case, we only have 1 resort.
 528	 */
 529
 530	/* Try to over-allocate to reduce reallocations and fragmentation. */
 531	ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1,
 532						   4096, 0, end);
 533	if (ret == 0)
 534		return compression_threshold;
 535
 536again:
 537	/* HW's ability to limit the CFB is 1:4 */
 538	if (compression_threshold > 4 ||
 539	    (fb_cpp == 2 && compression_threshold == 2))
 540		return 0;
 541
 542	ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1,
 543						   4096, 0, end);
 544	if (ret && INTEL_INFO(dev_priv)->gen <= 4) {
 545		return 0;
 546	} else if (ret) {
 547		compression_threshold <<= 1;
 548		goto again;
 549	} else {
 550		return compression_threshold;
 551	}
 552}
 553
 554static int intel_fbc_alloc_cfb(struct intel_crtc *crtc)
 555{
 556	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 557	struct intel_fbc *fbc = &dev_priv->fbc;
 558	struct drm_mm_node *uninitialized_var(compressed_llb);
 559	int size, fb_cpp, ret;
 560
 561	WARN_ON(drm_mm_node_allocated(&fbc->compressed_fb));
 562
 563	size = intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache);
 564	fb_cpp = drm_format_plane_cpp(fbc->state_cache.fb.pixel_format, 0);
 565
 566	ret = find_compression_threshold(dev_priv, &fbc->compressed_fb,
 567					 size, fb_cpp);
 568	if (!ret)
 569		goto err_llb;
 570	else if (ret > 1) {
 571		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");
 572
 573	}
 574
 575	fbc->threshold = ret;
 576
 577	if (INTEL_INFO(dev_priv)->gen >= 5)
 578		I915_WRITE(ILK_DPFC_CB_BASE, fbc->compressed_fb.start);
 579	else if (IS_GM45(dev_priv)) {
 580		I915_WRITE(DPFC_CB_BASE, fbc->compressed_fb.start);
 581	} else {
 582		compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 583		if (!compressed_llb)
 584			goto err_fb;
 585
 586		ret = i915_gem_stolen_insert_node(dev_priv, compressed_llb,
 587						  4096, 4096);
 588		if (ret)
 589			goto err_fb;
 590
 591		fbc->compressed_llb = compressed_llb;
 592
 593		I915_WRITE(FBC_CFB_BASE,
 594			   dev_priv->mm.stolen_base + fbc->compressed_fb.start);
 595		I915_WRITE(FBC_LL_BASE,
 596			   dev_priv->mm.stolen_base + compressed_llb->start);
 597	}
 598
 599	DRM_DEBUG_KMS("reserved %llu bytes of contiguous stolen space for FBC, threshold: %d\n",
 600		      fbc->compressed_fb.size, fbc->threshold);
 601
 602	return 0;
 603
 604err_fb:
 605	kfree(compressed_llb);
 606	i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
 607err_llb:
 608	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);
 609	return -ENOSPC;
 610}
 611
 612static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
 613{
 614	struct intel_fbc *fbc = &dev_priv->fbc;
 615
 616	if (drm_mm_node_allocated(&fbc->compressed_fb))
 617		i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
 618
 619	if (fbc->compressed_llb) {
 620		i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb);
 621		kfree(fbc->compressed_llb);
 622	}
 623}
 624
 625void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
 626{
 627	struct intel_fbc *fbc = &dev_priv->fbc;
 628
 629	if (!fbc_supported(dev_priv))
 630		return;
 631
 632	mutex_lock(&fbc->lock);
 633	__intel_fbc_cleanup_cfb(dev_priv);
 634	mutex_unlock(&fbc->lock);
 635}
 636
 637static bool stride_is_valid(struct drm_i915_private *dev_priv,
 638			    unsigned int stride)
 639{
 640	/* These should have been caught earlier. */
 641	WARN_ON(stride < 512);
 642	WARN_ON((stride & (64 - 1)) != 0);
 643
 644	/* Below are the additional FBC restrictions. */
 645
 646	if (IS_GEN2(dev_priv) || IS_GEN3(dev_priv))
 647		return stride == 4096 || stride == 8192;
 648
 649	if (IS_GEN4(dev_priv) && !IS_G4X(dev_priv) && stride < 2048)
 650		return false;
 651
 652	if (stride > 16384)
 653		return false;
 654
 655	return true;
 656}
 657
 658static bool pixel_format_is_valid(struct drm_i915_private *dev_priv,
 659				  uint32_t pixel_format)
 660{
 661	switch (pixel_format) {
 662	case DRM_FORMAT_XRGB8888:
 663	case DRM_FORMAT_XBGR8888:
 664		return true;
 665	case DRM_FORMAT_XRGB1555:
 666	case DRM_FORMAT_RGB565:
 667		/* 16bpp not supported on gen2 */
 668		if (IS_GEN2(dev_priv))
 669			return false;
 670		/* WaFbcOnly1to1Ratio:ctg */
 671		if (IS_G4X(dev_priv))
 672			return false;
 673		return true;
 674	default:
 675		return false;
 676	}
 677}
 678
 679/*
 680 * For some reason, the hardware tracking starts looking at whatever we
 681 * programmed as the display plane base address register. It does not look at
 682 * the X and Y offset registers. That's why we look at the crtc->adjusted{x,y}
 683 * variables instead of just looking at the pipe/plane size.
 684 */
 685static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc)
 686{
 687	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 688	struct intel_fbc *fbc = &dev_priv->fbc;
 689	unsigned int effective_w, effective_h, max_w, max_h;
 690
 691	if (INTEL_INFO(dev_priv)->gen >= 8 || IS_HASWELL(dev_priv)) {
 692		max_w = 4096;
 693		max_h = 4096;
 694	} else if (IS_G4X(dev_priv) || INTEL_INFO(dev_priv)->gen >= 5) {
 695		max_w = 4096;
 696		max_h = 2048;
 697	} else {
 698		max_w = 2048;
 699		max_h = 1536;
 700	}
 701
 702	intel_fbc_get_plane_source_size(&fbc->state_cache, &effective_w,
 703					&effective_h);
 704	effective_w += crtc->adjusted_x;
 705	effective_h += crtc->adjusted_y;
 706
 707	return effective_w <= max_w && effective_h <= max_h;
 708}
 709
 710static void intel_fbc_update_state_cache(struct intel_crtc *crtc)
 
 
 711{
 712	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 713	struct intel_fbc *fbc = &dev_priv->fbc;
 714	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 715	struct intel_crtc_state *crtc_state =
 716		to_intel_crtc_state(crtc->base.state);
 717	struct intel_plane_state *plane_state =
 718		to_intel_plane_state(crtc->base.primary->state);
 719	struct drm_framebuffer *fb = plane_state->base.fb;
 720	struct drm_i915_gem_object *obj;
 721
 722	WARN_ON(!drm_modeset_is_locked(&crtc->base.mutex));
 723	WARN_ON(!drm_modeset_is_locked(&crtc->base.primary->mutex));
 724
 725	cache->crtc.mode_flags = crtc_state->base.adjusted_mode.flags;
 726	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 727		cache->crtc.hsw_bdw_pixel_rate =
 728			ilk_pipe_pixel_rate(crtc_state);
 729
 730	cache->plane.rotation = plane_state->base.rotation;
 731	cache->plane.src_w = drm_rect_width(&plane_state->src) >> 16;
 732	cache->plane.src_h = drm_rect_height(&plane_state->src) >> 16;
 733	cache->plane.visible = plane_state->visible;
 734
 735	if (!cache->plane.visible)
 736		return;
 737
 738	obj = intel_fb_obj(fb);
 739
 740	/* FIXME: We lack the proper locking here, so only run this on the
 741	 * platforms that need. */
 742	if (INTEL_INFO(dev_priv)->gen >= 5 && INTEL_INFO(dev_priv)->gen < 7)
 743		cache->fb.ilk_ggtt_offset = i915_gem_obj_ggtt_offset(obj);
 744	cache->fb.pixel_format = fb->pixel_format;
 745	cache->fb.stride = fb->pitches[0];
 746	cache->fb.fence_reg = obj->fence_reg;
 747	cache->fb.tiling_mode = obj->tiling_mode;
 748}
 749
 750static bool intel_fbc_can_activate(struct intel_crtc *crtc)
 751{
 752	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 753	struct intel_fbc *fbc = &dev_priv->fbc;
 754	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 755
 756	if (!cache->plane.visible) {
 
 
 
 
 
 
 
 
 757		fbc->no_fbc_reason = "primary plane not visible";
 758		return false;
 759	}
 760
 761	if ((cache->crtc.mode_flags & DRM_MODE_FLAG_INTERLACE) ||
 762	    (cache->crtc.mode_flags & DRM_MODE_FLAG_DBLSCAN)) {
 763		fbc->no_fbc_reason = "incompatible mode";
 764		return false;
 765	}
 766
 767	if (!intel_fbc_hw_tracking_covers_screen(crtc)) {
 768		fbc->no_fbc_reason = "mode too large for compression";
 769		return false;
 770	}
 771
 772	/* The use of a CPU fence is mandatory in order to detect writes
 773	 * by the CPU to the scanout and trigger updates to the FBC.
 
 
 
 
 774	 */
 775	if (cache->fb.tiling_mode != I915_TILING_X ||
 776	    cache->fb.fence_reg == I915_FENCE_REG_NONE) {
 777		fbc->no_fbc_reason = "framebuffer not tiled or fenced";
 778		return false;
 779	}
 780	if (INTEL_INFO(dev_priv)->gen <= 4 && !IS_G4X(dev_priv) &&
 781	    cache->plane.rotation != BIT(DRM_ROTATE_0)) {
 782		fbc->no_fbc_reason = "rotation unsupported";
 783		return false;
 784	}
 785
 786	if (!stride_is_valid(dev_priv, cache->fb.stride)) {
 787		fbc->no_fbc_reason = "framebuffer stride not supported";
 788		return false;
 789	}
 790
 791	if (!pixel_format_is_valid(dev_priv, cache->fb.pixel_format)) {
 792		fbc->no_fbc_reason = "pixel format is invalid";
 793		return false;
 794	}
 795
 796	/* WaFbcExceedCdClockThreshold:hsw,bdw */
 797	if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
 798	    cache->crtc.hsw_bdw_pixel_rate >= dev_priv->cdclk_freq * 95 / 100) {
 799		fbc->no_fbc_reason = "pixel rate is too big";
 800		return false;
 801	}
 802
 803	/* It is possible for the required CFB size change without a
 804	 * crtc->disable + crtc->enable since it is possible to change the
 805	 * stride without triggering a full modeset. Since we try to
 806	 * over-allocate the CFB, there's a chance we may keep FBC enabled even
 807	 * if this happens, but if we exceed the current CFB size we'll have to
 808	 * disable FBC. Notice that it would be possible to disable FBC, wait
 809	 * for a frame, free the stolen node, then try to reenable FBC in case
 810	 * we didn't get any invalidate/deactivate calls, but this would require
 811	 * a lot of tracking just for a specific case. If we conclude it's an
 812	 * important case, we can implement it later. */
 813	if (intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache) >
 814	    fbc->compressed_fb.size * fbc->threshold) {
 815		fbc->no_fbc_reason = "CFB requirements changed";
 816		return false;
 817	}
 818
 819	return true;
 820}
 821
 822static bool intel_fbc_can_choose(struct intel_crtc *crtc)
 823{
 824	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 825	struct intel_fbc *fbc = &dev_priv->fbc;
 826	bool enable_by_default = IS_HASWELL(dev_priv) ||
 827				 IS_BROADWELL(dev_priv);
 828
 829	if (intel_vgpu_active(dev_priv->dev)) {
 830		fbc->no_fbc_reason = "VGPU is active";
 831		return false;
 832	}
 833
 834	if (i915.enable_fbc < 0 && !enable_by_default) {
 835		fbc->no_fbc_reason = "disabled per chip default";
 836		return false;
 837	}
 838
 839	if (!i915.enable_fbc) {
 840		fbc->no_fbc_reason = "disabled per module param";
 841		return false;
 842	}
 843
 844	if (fbc_on_pipe_a_only(dev_priv) && crtc->pipe != PIPE_A) {
 845		fbc->no_fbc_reason = "no enabled pipes can have FBC";
 846		return false;
 847	}
 848
 849	if (fbc_on_plane_a_only(dev_priv) && crtc->plane != PLANE_A) {
 850		fbc->no_fbc_reason = "no enabled planes can have FBC";
 851		return false;
 852	}
 853
 854	return true;
 855}
 856
 857static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
 858				     struct intel_fbc_reg_params *params)
 859{
 860	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 861	struct intel_fbc *fbc = &dev_priv->fbc;
 862	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 863
 864	/* Since all our fields are integer types, use memset here so the
 865	 * comparison function can rely on memcmp because the padding will be
 866	 * zero. */
 867	memset(params, 0, sizeof(*params));
 868
 
 
 869	params->crtc.pipe = crtc->pipe;
 870	params->crtc.plane = crtc->plane;
 871	params->crtc.fence_y_offset = get_crtc_fence_y_offset(crtc);
 872
 873	params->fb.pixel_format = cache->fb.pixel_format;
 874	params->fb.stride = cache->fb.stride;
 875	params->fb.fence_reg = cache->fb.fence_reg;
 876
 877	params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);
 878
 879	params->fb.ggtt_offset = cache->fb.ilk_ggtt_offset;
 880}
 881
 882static bool intel_fbc_reg_params_equal(struct intel_fbc_reg_params *params1,
 883				       struct intel_fbc_reg_params *params2)
 884{
 885	/* We can use this since intel_fbc_get_reg_params() does a memset. */
 886	return memcmp(params1, params2, sizeof(*params1)) == 0;
 887}
 888
 889void intel_fbc_pre_update(struct intel_crtc *crtc)
 
 
 890{
 891	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 892	struct intel_fbc *fbc = &dev_priv->fbc;
 893
 894	if (!fbc_supported(dev_priv))
 895		return;
 896
 897	mutex_lock(&fbc->lock);
 898
 899	if (!multiple_pipes_ok(crtc)) {
 900		fbc->no_fbc_reason = "more than one pipe active";
 901		goto deactivate;
 902	}
 903
 904	if (!fbc->enabled || fbc->crtc != crtc)
 905		goto unlock;
 906
 907	intel_fbc_update_state_cache(crtc);
 908
 909deactivate:
 910	intel_fbc_deactivate(dev_priv);
 911unlock:
 912	mutex_unlock(&fbc->lock);
 913}
 914
 915static void __intel_fbc_post_update(struct intel_crtc *crtc)
 916{
 917	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 918	struct intel_fbc *fbc = &dev_priv->fbc;
 919	struct intel_fbc_reg_params old_params;
 920
 921	WARN_ON(!mutex_is_locked(&fbc->lock));
 922
 923	if (!fbc->enabled || fbc->crtc != crtc)
 924		return;
 925
 926	if (!intel_fbc_can_activate(crtc)) {
 927		WARN_ON(fbc->active);
 928		return;
 929	}
 930
 931	old_params = fbc->params;
 932	intel_fbc_get_reg_params(crtc, &fbc->params);
 933
 934	/* If the scanout has not changed, don't modify the FBC settings.
 935	 * Note that we make the fundamental assumption that the fb->obj
 936	 * cannot be unpinned (and have its GTT offset and fence revoked)
 937	 * without first being decoupled from the scanout and FBC disabled.
 938	 */
 939	if (fbc->active &&
 940	    intel_fbc_reg_params_equal(&old_params, &fbc->params))
 941		return;
 942
 943	intel_fbc_deactivate(dev_priv);
 944	intel_fbc_schedule_activation(crtc);
 945	fbc->no_fbc_reason = "FBC enabled (active or scheduled)";
 946}
 947
 948void intel_fbc_post_update(struct intel_crtc *crtc)
 949{
 950	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
 951	struct intel_fbc *fbc = &dev_priv->fbc;
 952
 953	if (!fbc_supported(dev_priv))
 954		return;
 955
 956	mutex_lock(&fbc->lock);
 957	__intel_fbc_post_update(crtc);
 958	mutex_unlock(&fbc->lock);
 959}
 960
 961static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
 962{
 963	if (fbc->enabled)
 964		return to_intel_plane(fbc->crtc->base.primary)->frontbuffer_bit;
 965	else
 966		return fbc->possible_framebuffer_bits;
 967}
 968
 969void intel_fbc_invalidate(struct drm_i915_private *dev_priv,
 970			  unsigned int frontbuffer_bits,
 971			  enum fb_op_origin origin)
 972{
 973	struct intel_fbc *fbc = &dev_priv->fbc;
 974
 975	if (!fbc_supported(dev_priv))
 976		return;
 977
 978	if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
 979		return;
 980
 981	mutex_lock(&fbc->lock);
 982
 983	fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
 984
 985	if (fbc->enabled && fbc->busy_bits)
 986		intel_fbc_deactivate(dev_priv);
 987
 988	mutex_unlock(&fbc->lock);
 989}
 990
 991void intel_fbc_flush(struct drm_i915_private *dev_priv,
 992		     unsigned int frontbuffer_bits, enum fb_op_origin origin)
 993{
 994	struct intel_fbc *fbc = &dev_priv->fbc;
 995
 996	if (!fbc_supported(dev_priv))
 997		return;
 998
 999	if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
1000		return;
1001
1002	mutex_lock(&fbc->lock);
1003
1004	fbc->busy_bits &= ~frontbuffer_bits;
1005
 
 
 
1006	if (!fbc->busy_bits && fbc->enabled &&
1007	    (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
1008		if (fbc->active)
1009			intel_fbc_recompress(dev_priv);
1010		else
1011			__intel_fbc_post_update(fbc->crtc);
1012	}
1013
 
1014	mutex_unlock(&fbc->lock);
1015}
1016
1017/**
1018 * intel_fbc_choose_crtc - select a CRTC to enable FBC on
1019 * @dev_priv: i915 device instance
1020 * @state: the atomic state structure
1021 *
1022 * This function looks at the proposed state for CRTCs and planes, then chooses
1023 * which pipe is going to have FBC by setting intel_crtc_state->enable_fbc to
1024 * true.
1025 *
1026 * Later, intel_fbc_enable is going to look for state->enable_fbc and then maybe
1027 * enable FBC for the chosen CRTC. If it does, it will set dev_priv->fbc.crtc.
1028 */
1029void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv,
1030			   struct drm_atomic_state *state)
1031{
1032	struct intel_fbc *fbc = &dev_priv->fbc;
1033	struct drm_crtc *crtc;
1034	struct drm_crtc_state *crtc_state;
1035	struct drm_plane *plane;
1036	struct drm_plane_state *plane_state;
1037	bool fbc_crtc_present = false;
1038	int i, j;
1039
1040	mutex_lock(&fbc->lock);
1041
1042	for_each_crtc_in_state(state, crtc, crtc_state, i) {
1043		if (fbc->crtc == to_intel_crtc(crtc)) {
1044			fbc_crtc_present = true;
1045			break;
1046		}
1047	}
1048	/* This atomic commit doesn't involve the CRTC currently tied to FBC. */
1049	if (!fbc_crtc_present && fbc->crtc != NULL)
1050		goto out;
1051
1052	/* Simply choose the first CRTC that is compatible and has a visible
1053	 * plane. We could go for fancier schemes such as checking the plane
1054	 * size, but this would just affect the few platforms that don't tie FBC
1055	 * to pipe or plane A. */
1056	for_each_plane_in_state(state, plane, plane_state, i) {
1057		struct intel_plane_state *intel_plane_state =
1058			to_intel_plane_state(plane_state);
 
 
1059
1060		if (!intel_plane_state->visible)
1061			continue;
1062
1063		for_each_crtc_in_state(state, crtc, crtc_state, j) {
1064			struct intel_crtc_state *intel_crtc_state =
1065				to_intel_crtc_state(crtc_state);
1066
1067			if (plane_state->crtc != crtc)
1068				continue;
1069
1070			if (!intel_fbc_can_choose(to_intel_crtc(crtc)))
1071				break;
1072
1073			intel_crtc_state->enable_fbc = true;
1074			goto out;
1075		}
1076	}
1077
 
 
 
1078out:
1079	mutex_unlock(&fbc->lock);
1080}
1081
1082/**
1083 * intel_fbc_enable: tries to enable FBC on the CRTC
1084 * @crtc: the CRTC
 
 
1085 *
1086 * This function checks if the given CRTC was chosen for FBC, then enables it if
1087 * possible. Notice that it doesn't activate FBC. It is valid to call
1088 * intel_fbc_enable multiple times for the same pipe without an
1089 * intel_fbc_disable in the middle, as long as it is deactivated.
1090 */
1091void intel_fbc_enable(struct intel_crtc *crtc)
 
 
1092{
1093	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
1094	struct intel_fbc *fbc = &dev_priv->fbc;
1095
1096	if (!fbc_supported(dev_priv))
1097		return;
1098
1099	mutex_lock(&fbc->lock);
1100
1101	if (fbc->enabled) {
1102		WARN_ON(fbc->crtc == NULL);
1103		if (fbc->crtc == crtc) {
1104			WARN_ON(!crtc->config->enable_fbc);
1105			WARN_ON(fbc->active);
1106		}
1107		goto out;
1108	}
1109
1110	if (!crtc->config->enable_fbc)
1111		goto out;
1112
1113	WARN_ON(fbc->active);
1114	WARN_ON(fbc->crtc != NULL);
1115
1116	intel_fbc_update_state_cache(crtc);
1117	if (intel_fbc_alloc_cfb(crtc)) {
1118		fbc->no_fbc_reason = "not enough stolen memory";
1119		goto out;
1120	}
1121
1122	DRM_DEBUG_KMS("Enabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1123	fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1124
1125	fbc->enabled = true;
1126	fbc->crtc = crtc;
1127out:
1128	mutex_unlock(&fbc->lock);
1129}
1130
1131/**
1132 * __intel_fbc_disable - disable FBC
1133 * @dev_priv: i915 device instance
1134 *
1135 * This is the low level function that actually disables FBC. Callers should
1136 * grab the FBC lock.
1137 */
1138static void __intel_fbc_disable(struct drm_i915_private *dev_priv)
1139{
1140	struct intel_fbc *fbc = &dev_priv->fbc;
1141	struct intel_crtc *crtc = fbc->crtc;
1142
1143	WARN_ON(!mutex_is_locked(&fbc->lock));
1144	WARN_ON(!fbc->enabled);
1145	WARN_ON(fbc->active);
1146	WARN_ON(crtc->active);
1147
1148	DRM_DEBUG_KMS("Disabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1149
1150	__intel_fbc_cleanup_cfb(dev_priv);
1151
1152	fbc->enabled = false;
1153	fbc->crtc = NULL;
1154}
1155
1156/**
1157 * intel_fbc_disable - disable FBC if it's associated with crtc
1158 * @crtc: the CRTC
1159 *
1160 * This function disables FBC if it's associated with the provided CRTC.
1161 */
1162void intel_fbc_disable(struct intel_crtc *crtc)
1163{
1164	struct drm_i915_private *dev_priv = crtc->base.dev->dev_private;
1165	struct intel_fbc *fbc = &dev_priv->fbc;
1166
1167	if (!fbc_supported(dev_priv))
1168		return;
1169
1170	mutex_lock(&fbc->lock);
1171	if (fbc->crtc == crtc) {
1172		WARN_ON(!fbc->enabled);
1173		WARN_ON(fbc->active);
1174		__intel_fbc_disable(dev_priv);
1175	}
1176	mutex_unlock(&fbc->lock);
1177
1178	cancel_work_sync(&fbc->work.work);
1179}
1180
1181/**
1182 * intel_fbc_global_disable - globally disable FBC
1183 * @dev_priv: i915 device instance
1184 *
1185 * This function disables FBC regardless of which CRTC is associated with it.
1186 */
1187void intel_fbc_global_disable(struct drm_i915_private *dev_priv)
1188{
1189	struct intel_fbc *fbc = &dev_priv->fbc;
1190
1191	if (!fbc_supported(dev_priv))
1192		return;
1193
1194	mutex_lock(&fbc->lock);
1195	if (fbc->enabled)
1196		__intel_fbc_disable(dev_priv);
1197	mutex_unlock(&fbc->lock);
1198
1199	cancel_work_sync(&fbc->work.work);
1200}
1201
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1202/**
1203 * intel_fbc_init_pipe_state - initialize FBC's CRTC visibility tracking
1204 * @dev_priv: i915 device instance
1205 *
1206 * The FBC code needs to track CRTC visibility since the older platforms can't
1207 * have FBC enabled while multiple pipes are used. This function does the
1208 * initial setup at driver load to make sure FBC is matching the real hardware.
1209 */
1210void intel_fbc_init_pipe_state(struct drm_i915_private *dev_priv)
1211{
1212	struct intel_crtc *crtc;
1213
1214	/* Don't even bother tracking anything if we don't need. */
1215	if (!no_fbc_on_multiple_pipes(dev_priv))
1216		return;
1217
1218	for_each_intel_crtc(dev_priv->dev, crtc)
1219		if (intel_crtc_active(&crtc->base) &&
1220		    to_intel_plane_state(crtc->base.primary->state)->visible)
1221			dev_priv->fbc.visible_pipes_mask |= (1 << crtc->pipe);
1222}
1223
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1224/**
1225 * intel_fbc_init - Initialize FBC
1226 * @dev_priv: the i915 device
1227 *
1228 * This function might be called during PM init process.
1229 */
1230void intel_fbc_init(struct drm_i915_private *dev_priv)
1231{
1232	struct intel_fbc *fbc = &dev_priv->fbc;
1233	enum pipe pipe;
1234
1235	INIT_WORK(&fbc->work.work, intel_fbc_work_fn);
 
1236	mutex_init(&fbc->lock);
1237	fbc->enabled = false;
1238	fbc->active = false;
1239	fbc->work.scheduled = false;
1240
 
 
 
 
 
 
1241	if (!HAS_FBC(dev_priv)) {
1242		fbc->no_fbc_reason = "unsupported by this chipset";
1243		return;
1244	}
1245
1246	for_each_pipe(dev_priv, pipe) {
1247		fbc->possible_framebuffer_bits |=
1248				INTEL_FRONTBUFFER_PRIMARY(pipe);
1249
1250		if (fbc_on_pipe_a_only(dev_priv))
1251			break;
1252	}
1253
1254	/* This value was pulled out of someone's hat */
1255	if (INTEL_INFO(dev_priv)->gen <= 4 && !IS_GM45(dev_priv))
1256		I915_WRITE(FBC_CONTROL, 500 << FBC_CTL_INTERVAL_SHIFT);
1257
1258	/* We still don't have any sort of hardware state readout for FBC, so
1259	 * deactivate it in case the BIOS activated it to make sure software
1260	 * matches the hardware state. */
1261	if (intel_fbc_hw_is_active(dev_priv))
1262		intel_fbc_hw_deactivate(dev_priv);
1263}
v4.10.11
   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
  21 * DEALINGS IN THE SOFTWARE.
  22 */
  23
  24/**
  25 * DOC: Frame Buffer Compression (FBC)
  26 *
  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.
  30 *
  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.
  34 *
  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.
  39 */
  40
  41#include "intel_drv.h"
  42#include "i915_drv.h"
  43
  44static inline bool fbc_supported(struct drm_i915_private *dev_priv)
  45{
  46	return HAS_FBC(dev_priv);
  47}
  48
  49static inline bool fbc_on_pipe_a_only(struct drm_i915_private *dev_priv)
  50{
  51	return IS_HASWELL(dev_priv) || INTEL_GEN(dev_priv) >= 8;
  52}
  53
  54static inline bool fbc_on_plane_a_only(struct drm_i915_private *dev_priv)
  55{
  56	return INTEL_GEN(dev_priv) < 4;
  57}
  58
  59static inline bool no_fbc_on_multiple_pipes(struct drm_i915_private *dev_priv)
  60{
  61	return INTEL_GEN(dev_priv) <= 3;
  62}
  63
  64/*
  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.
  71 */
  72static unsigned int get_crtc_fence_y_offset(struct intel_crtc *crtc)
  73{
  74	return crtc->base.y - crtc->adjusted_y;
  75}
  76
  77/*
  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.
  81 */
  82static void intel_fbc_get_plane_source_size(struct intel_fbc_state_cache *cache,
  83					    int *width, int *height)
  84{
  85	int w, h;
  86
  87	if (drm_rotation_90_or_270(cache->plane.rotation)) {
  88		w = cache->plane.src_h;
  89		h = cache->plane.src_w;
  90	} else {
  91		w = cache->plane.src_w;
  92		h = cache->plane.src_h;
  93	}
  94
  95	if (width)
  96		*width = w;
  97	if (height)
  98		*height = h;
  99}
 100
 101static int intel_fbc_calculate_cfb_size(struct drm_i915_private *dev_priv,
 102					struct intel_fbc_state_cache *cache)
 103{
 104	int lines;
 105
 106	intel_fbc_get_plane_source_size(cache, NULL, &lines);
 107	if (INTEL_GEN(dev_priv) == 7)
 108		lines = min(lines, 2048);
 109	else if (INTEL_GEN(dev_priv) >= 8)
 110		lines = min(lines, 2560);
 111
 112	/* Hardware needs the full buffer stride, not just the active area. */
 113	return lines * cache->fb.stride;
 114}
 115
 116static void i8xx_fbc_deactivate(struct drm_i915_private *dev_priv)
 117{
 118	u32 fbc_ctl;
 119
 120	/* Disable compression */
 121	fbc_ctl = I915_READ(FBC_CONTROL);
 122	if ((fbc_ctl & FBC_CTL_EN) == 0)
 123		return;
 124
 125	fbc_ctl &= ~FBC_CTL_EN;
 126	I915_WRITE(FBC_CONTROL, fbc_ctl);
 127
 128	/* Wait for compressing bit to clear */
 129	if (intel_wait_for_register(dev_priv,
 130				    FBC_STATUS, FBC_STAT_COMPRESSING, 0,
 131				    10)) {
 132		DRM_DEBUG_KMS("FBC idle timed out\n");
 133		return;
 134	}
 135}
 136
 137static void i8xx_fbc_activate(struct drm_i915_private *dev_priv)
 138{
 139	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 140	int cfb_pitch;
 141	int i;
 142	u32 fbc_ctl;
 143
 144	/* Note: fbc.threshold == 1 for i8xx */
 145	cfb_pitch = params->cfb_size / FBC_LL_SIZE;
 146	if (params->fb.stride < cfb_pitch)
 147		cfb_pitch = params->fb.stride;
 148
 149	/* FBC_CTL wants 32B or 64B units */
 150	if (IS_GEN2(dev_priv))
 151		cfb_pitch = (cfb_pitch / 32) - 1;
 152	else
 153		cfb_pitch = (cfb_pitch / 64) - 1;
 154
 155	/* Clear old tags */
 156	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
 157		I915_WRITE(FBC_TAG(i), 0);
 158
 159	if (IS_GEN4(dev_priv)) {
 160		u32 fbc_ctl2;
 161
 162		/* Set it up... */
 163		fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
 164		fbc_ctl2 |= FBC_CTL_PLANE(params->crtc.plane);
 165		I915_WRITE(FBC_CONTROL2, fbc_ctl2);
 166		I915_WRITE(FBC_FENCE_OFF, params->crtc.fence_y_offset);
 167	}
 168
 169	/* enable it... */
 170	fbc_ctl = I915_READ(FBC_CONTROL);
 171	fbc_ctl &= 0x3fff << FBC_CTL_INTERVAL_SHIFT;
 172	fbc_ctl |= FBC_CTL_EN | FBC_CTL_PERIODIC;
 173	if (IS_I945GM(dev_priv))
 174		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
 175	fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
 176	fbc_ctl |= params->vma->fence->id;
 177	I915_WRITE(FBC_CONTROL, fbc_ctl);
 178}
 179
 180static bool i8xx_fbc_is_active(struct drm_i915_private *dev_priv)
 181{
 182	return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
 183}
 184
 185static void g4x_fbc_activate(struct drm_i915_private *dev_priv)
 186{
 187	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 188	u32 dpfc_ctl;
 189
 190	dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane) | DPFC_SR_EN;
 191	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 192		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 193	else
 194		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 
 195
 196	if (params->vma->fence) {
 197		dpfc_ctl |= DPFC_CTL_FENCE_EN | params->vma->fence->id;
 198		I915_WRITE(DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
 199	} else {
 200		I915_WRITE(DPFC_FENCE_YOFF, 0);
 201	}
 202
 203	/* enable it... */
 204	I915_WRITE(DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 205}
 206
 207static void g4x_fbc_deactivate(struct drm_i915_private *dev_priv)
 208{
 209	u32 dpfc_ctl;
 210
 211	/* Disable compression */
 212	dpfc_ctl = I915_READ(DPFC_CONTROL);
 213	if (dpfc_ctl & DPFC_CTL_EN) {
 214		dpfc_ctl &= ~DPFC_CTL_EN;
 215		I915_WRITE(DPFC_CONTROL, dpfc_ctl);
 216	}
 217}
 218
 219static bool g4x_fbc_is_active(struct drm_i915_private *dev_priv)
 220{
 221	return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
 222}
 223
 224/* This function forces a CFB recompression through the nuke operation. */
 225static void intel_fbc_recompress(struct drm_i915_private *dev_priv)
 226{
 227	I915_WRITE(MSG_FBC_REND_STATE, FBC_REND_NUKE);
 228	POSTING_READ(MSG_FBC_REND_STATE);
 229}
 230
 231static void ilk_fbc_activate(struct drm_i915_private *dev_priv)
 232{
 233	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 234	u32 dpfc_ctl;
 235	int threshold = dev_priv->fbc.threshold;
 236
 237	dpfc_ctl = DPFC_CTL_PLANE(params->crtc.plane);
 238	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 239		threshold++;
 240
 241	switch (threshold) {
 242	case 4:
 243	case 3:
 244		dpfc_ctl |= DPFC_CTL_LIMIT_4X;
 245		break;
 246	case 2:
 247		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 248		break;
 249	case 1:
 250		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 251		break;
 252	}
 253
 254	if (params->vma->fence) {
 255		dpfc_ctl |= DPFC_CTL_FENCE_EN;
 256		if (IS_GEN5(dev_priv))
 257			dpfc_ctl |= params->vma->fence->id;
 258		if (IS_GEN6(dev_priv)) {
 259			I915_WRITE(SNB_DPFC_CTL_SA,
 260				   SNB_CPU_FENCE_ENABLE |
 261				   params->vma->fence->id);
 262			I915_WRITE(DPFC_CPU_FENCE_OFFSET,
 263				   params->crtc.fence_y_offset);
 264		}
 265	} else {
 266		if (IS_GEN6(dev_priv)) {
 267			I915_WRITE(SNB_DPFC_CTL_SA, 0);
 268			I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
 269		}
 270	}
 271
 272	I915_WRITE(ILK_DPFC_FENCE_YOFF, params->crtc.fence_y_offset);
 273	I915_WRITE(ILK_FBC_RT_BASE,
 274		   i915_ggtt_offset(params->vma) | ILK_FBC_RT_VALID);
 275	/* enable it... */
 276	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 277
 
 
 
 
 
 
 278	intel_fbc_recompress(dev_priv);
 279}
 280
 281static void ilk_fbc_deactivate(struct drm_i915_private *dev_priv)
 282{
 283	u32 dpfc_ctl;
 284
 285	/* Disable compression */
 286	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
 287	if (dpfc_ctl & DPFC_CTL_EN) {
 288		dpfc_ctl &= ~DPFC_CTL_EN;
 289		I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);
 290	}
 291}
 292
 293static bool ilk_fbc_is_active(struct drm_i915_private *dev_priv)
 294{
 295	return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
 296}
 297
 298static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
 299{
 300	struct intel_fbc_reg_params *params = &dev_priv->fbc.params;
 301	u32 dpfc_ctl;
 302	int threshold = dev_priv->fbc.threshold;
 303
 304	dpfc_ctl = 0;
 305	if (IS_IVYBRIDGE(dev_priv))
 306		dpfc_ctl |= IVB_DPFC_CTL_PLANE(params->crtc.plane);
 307
 308	if (drm_format_plane_cpp(params->fb.pixel_format, 0) == 2)
 309		threshold++;
 310
 311	switch (threshold) {
 312	case 4:
 313	case 3:
 314		dpfc_ctl |= DPFC_CTL_LIMIT_4X;
 315		break;
 316	case 2:
 317		dpfc_ctl |= DPFC_CTL_LIMIT_2X;
 318		break;
 319	case 1:
 320		dpfc_ctl |= DPFC_CTL_LIMIT_1X;
 321		break;
 322	}
 323
 324	if (params->vma->fence) {
 325		dpfc_ctl |= IVB_DPFC_CTL_FENCE_EN;
 326		I915_WRITE(SNB_DPFC_CTL_SA,
 327			   SNB_CPU_FENCE_ENABLE |
 328			   params->vma->fence->id);
 329		I915_WRITE(DPFC_CPU_FENCE_OFFSET, params->crtc.fence_y_offset);
 330	} else {
 331		I915_WRITE(SNB_DPFC_CTL_SA,0);
 332		I915_WRITE(DPFC_CPU_FENCE_OFFSET, 0);
 333	}
 334
 335	if (dev_priv->fbc.false_color)
 336		dpfc_ctl |= FBC_CTL_FALSE_COLOR;
 337
 338	if (IS_IVYBRIDGE(dev_priv)) {
 339		/* WaFbcAsynchFlipDisableFbcQueue:ivb */
 340		I915_WRITE(ILK_DISPLAY_CHICKEN1,
 341			   I915_READ(ILK_DISPLAY_CHICKEN1) |
 342			   ILK_FBCQ_DIS);
 343	} else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
 344		/* WaFbcAsynchFlipDisableFbcQueue:hsw,bdw */
 345		I915_WRITE(CHICKEN_PIPESL_1(params->crtc.pipe),
 346			   I915_READ(CHICKEN_PIPESL_1(params->crtc.pipe)) |
 347			   HSW_FBCQ_DIS);
 348	}
 349
 350	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 351
 
 
 
 
 352	intel_fbc_recompress(dev_priv);
 353}
 354
 355static bool intel_fbc_hw_is_active(struct drm_i915_private *dev_priv)
 356{
 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);
 361	else
 362		return i8xx_fbc_is_active(dev_priv);
 363}
 364
 365static void intel_fbc_hw_activate(struct drm_i915_private *dev_priv)
 366{
 367	struct intel_fbc *fbc = &dev_priv->fbc;
 368
 369	fbc->active = true;
 370
 371	if (INTEL_GEN(dev_priv) >= 7)
 372		gen7_fbc_activate(dev_priv);
 373	else if (INTEL_GEN(dev_priv) >= 5)
 374		ilk_fbc_activate(dev_priv);
 375	else if (IS_GM45(dev_priv))
 376		g4x_fbc_activate(dev_priv);
 377	else
 378		i8xx_fbc_activate(dev_priv);
 379}
 380
 381static void intel_fbc_hw_deactivate(struct drm_i915_private *dev_priv)
 382{
 383	struct intel_fbc *fbc = &dev_priv->fbc;
 384
 385	fbc->active = false;
 386
 387	if (INTEL_GEN(dev_priv) >= 5)
 388		ilk_fbc_deactivate(dev_priv);
 389	else if (IS_GM45(dev_priv))
 390		g4x_fbc_deactivate(dev_priv);
 391	else
 392		i8xx_fbc_deactivate(dev_priv);
 393}
 394
 395/**
 396 * intel_fbc_is_active - Is FBC active?
 397 * @dev_priv: i915 device instance
 398 *
 399 * This function is used to verify the current state of FBC.
 400 *
 401 * FIXME: This should be tracked in the plane config eventually
 402 * instead of queried at runtime for most callers.
 403 */
 404bool intel_fbc_is_active(struct drm_i915_private *dev_priv)
 405{
 406	return dev_priv->fbc.active;
 407}
 408
 409static void intel_fbc_work_fn(struct work_struct *__work)
 410{
 411	struct drm_i915_private *dev_priv =
 412		container_of(__work, struct drm_i915_private, fbc.work.work);
 413	struct intel_fbc *fbc = &dev_priv->fbc;
 414	struct intel_fbc_work *work = &fbc->work;
 415	struct intel_crtc *crtc = fbc->crtc;
 416	struct drm_vblank_crtc *vblank = &dev_priv->drm.vblank[crtc->pipe];
 417
 418	if (drm_crtc_vblank_get(&crtc->base)) {
 419		DRM_ERROR("vblank not available for FBC on pipe %c\n",
 420			  pipe_name(crtc->pipe));
 421
 422		mutex_lock(&fbc->lock);
 423		work->scheduled = false;
 424		mutex_unlock(&fbc->lock);
 425		return;
 426	}
 427
 428retry:
 429	/* Delay the actual enabling to let pageflipping cease and the
 430	 * display to settle before starting the compression. Note that
 431	 * this delay also serves a second purpose: it allows for a
 432	 * vblank to pass after disabling the FBC before we attempt
 433	 * to modify the control registers.
 434	 *
 435	 * WaFbcWaitForVBlankBeforeEnable:ilk,snb
 436	 *
 437	 * It is also worth mentioning that since work->scheduled_vblank can be
 438	 * updated multiple times by the other threads, hitting the timeout is
 439	 * not an error condition. We'll just end up hitting the "goto retry"
 440	 * case below.
 441	 */
 442	wait_event_timeout(vblank->queue,
 443		drm_crtc_vblank_count(&crtc->base) != work->scheduled_vblank,
 444		msecs_to_jiffies(50));
 445
 446	mutex_lock(&fbc->lock);
 447
 448	/* Were we cancelled? */
 449	if (!work->scheduled)
 450		goto out;
 451
 452	/* Were we delayed again while this function was sleeping? */
 453	if (drm_crtc_vblank_count(&crtc->base) == work->scheduled_vblank) {
 454		mutex_unlock(&fbc->lock);
 455		goto retry;
 456	}
 457
 458	intel_fbc_hw_activate(dev_priv);
 459
 460	work->scheduled = false;
 461
 462out:
 463	mutex_unlock(&fbc->lock);
 464	drm_crtc_vblank_put(&crtc->base);
 465}
 466
 467static void intel_fbc_schedule_activation(struct intel_crtc *crtc)
 468{
 469	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 470	struct intel_fbc *fbc = &dev_priv->fbc;
 471	struct intel_fbc_work *work = &fbc->work;
 472
 473	WARN_ON(!mutex_is_locked(&fbc->lock));
 474
 475	if (drm_crtc_vblank_get(&crtc->base)) {
 476		DRM_ERROR("vblank not available for FBC on pipe %c\n",
 477			  pipe_name(crtc->pipe));
 478		return;
 479	}
 480
 481	/* It is useless to call intel_fbc_cancel_work() or cancel_work() in
 482	 * this function since we're not releasing fbc.lock, so it won't have an
 483	 * opportunity to grab it to discover that it was cancelled. So we just
 484	 * update the expected jiffy count. */
 485	work->scheduled = true;
 486	work->scheduled_vblank = drm_crtc_vblank_count(&crtc->base);
 487	drm_crtc_vblank_put(&crtc->base);
 488
 489	schedule_work(&work->work);
 490}
 491
 492static void intel_fbc_deactivate(struct drm_i915_private *dev_priv)
 493{
 494	struct intel_fbc *fbc = &dev_priv->fbc;
 495
 496	WARN_ON(!mutex_is_locked(&fbc->lock));
 497
 498	/* Calling cancel_work() here won't help due to the fact that the work
 499	 * function grabs fbc->lock. Just set scheduled to false so the work
 500	 * function can know it was cancelled. */
 501	fbc->work.scheduled = false;
 502
 503	if (fbc->active)
 504		intel_fbc_hw_deactivate(dev_priv);
 505}
 506
 507static bool multiple_pipes_ok(struct intel_crtc *crtc,
 508			      struct intel_plane_state *plane_state)
 509{
 510	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 
 511	struct intel_fbc *fbc = &dev_priv->fbc;
 512	enum pipe pipe = crtc->pipe;
 513
 514	/* Don't even bother tracking anything we don't need. */
 515	if (!no_fbc_on_multiple_pipes(dev_priv))
 516		return true;
 517
 518	if (plane_state->base.visible)
 
 
 519		fbc->visible_pipes_mask |= (1 << pipe);
 520	else
 521		fbc->visible_pipes_mask &= ~(1 << pipe);
 522
 523	return (fbc->visible_pipes_mask & ~(1 << pipe)) != 0;
 524}
 525
 526static int find_compression_threshold(struct drm_i915_private *dev_priv,
 527				      struct drm_mm_node *node,
 528				      int size,
 529				      int fb_cpp)
 530{
 531	struct i915_ggtt *ggtt = &dev_priv->ggtt;
 532	int compression_threshold = 1;
 533	int ret;
 534	u64 end;
 535
 536	/* The FBC hardware for BDW/SKL doesn't have access to the stolen
 537	 * reserved range size, so it always assumes the maximum (8mb) is used.
 538	 * If we enable FBC using a CFB on that memory range we'll get FIFO
 539	 * underruns, even if that range is not reserved by the BIOS. */
 540	if (IS_BROADWELL(dev_priv) ||
 541	    IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv))
 542		end = ggtt->stolen_size - 8 * 1024 * 1024;
 543	else
 544		end = ggtt->stolen_usable_size;
 545
 546	/* HACK: This code depends on what we will do in *_enable_fbc. If that
 547	 * code changes, this code needs to change as well.
 548	 *
 549	 * The enable_fbc code will attempt to use one of our 2 compression
 550	 * thresholds, therefore, in that case, we only have 1 resort.
 551	 */
 552
 553	/* Try to over-allocate to reduce reallocations and fragmentation. */
 554	ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size <<= 1,
 555						   4096, 0, end);
 556	if (ret == 0)
 557		return compression_threshold;
 558
 559again:
 560	/* HW's ability to limit the CFB is 1:4 */
 561	if (compression_threshold > 4 ||
 562	    (fb_cpp == 2 && compression_threshold == 2))
 563		return 0;
 564
 565	ret = i915_gem_stolen_insert_node_in_range(dev_priv, node, size >>= 1,
 566						   4096, 0, end);
 567	if (ret && INTEL_GEN(dev_priv) <= 4) {
 568		return 0;
 569	} else if (ret) {
 570		compression_threshold <<= 1;
 571		goto again;
 572	} else {
 573		return compression_threshold;
 574	}
 575}
 576
 577static int intel_fbc_alloc_cfb(struct intel_crtc *crtc)
 578{
 579	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 580	struct intel_fbc *fbc = &dev_priv->fbc;
 581	struct drm_mm_node *uninitialized_var(compressed_llb);
 582	int size, fb_cpp, ret;
 583
 584	WARN_ON(drm_mm_node_allocated(&fbc->compressed_fb));
 585
 586	size = intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache);
 587	fb_cpp = drm_format_plane_cpp(fbc->state_cache.fb.pixel_format, 0);
 588
 589	ret = find_compression_threshold(dev_priv, &fbc->compressed_fb,
 590					 size, fb_cpp);
 591	if (!ret)
 592		goto err_llb;
 593	else if (ret > 1) {
 594		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");
 595
 596	}
 597
 598	fbc->threshold = ret;
 599
 600	if (INTEL_GEN(dev_priv) >= 5)
 601		I915_WRITE(ILK_DPFC_CB_BASE, fbc->compressed_fb.start);
 602	else if (IS_GM45(dev_priv)) {
 603		I915_WRITE(DPFC_CB_BASE, fbc->compressed_fb.start);
 604	} else {
 605		compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
 606		if (!compressed_llb)
 607			goto err_fb;
 608
 609		ret = i915_gem_stolen_insert_node(dev_priv, compressed_llb,
 610						  4096, 4096);
 611		if (ret)
 612			goto err_fb;
 613
 614		fbc->compressed_llb = compressed_llb;
 615
 616		I915_WRITE(FBC_CFB_BASE,
 617			   dev_priv->mm.stolen_base + fbc->compressed_fb.start);
 618		I915_WRITE(FBC_LL_BASE,
 619			   dev_priv->mm.stolen_base + compressed_llb->start);
 620	}
 621
 622	DRM_DEBUG_KMS("reserved %llu bytes of contiguous stolen space for FBC, threshold: %d\n",
 623		      fbc->compressed_fb.size, fbc->threshold);
 624
 625	return 0;
 626
 627err_fb:
 628	kfree(compressed_llb);
 629	i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
 630err_llb:
 631	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);
 632	return -ENOSPC;
 633}
 634
 635static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
 636{
 637	struct intel_fbc *fbc = &dev_priv->fbc;
 638
 639	if (drm_mm_node_allocated(&fbc->compressed_fb))
 640		i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb);
 641
 642	if (fbc->compressed_llb) {
 643		i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb);
 644		kfree(fbc->compressed_llb);
 645	}
 646}
 647
 648void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
 649{
 650	struct intel_fbc *fbc = &dev_priv->fbc;
 651
 652	if (!fbc_supported(dev_priv))
 653		return;
 654
 655	mutex_lock(&fbc->lock);
 656	__intel_fbc_cleanup_cfb(dev_priv);
 657	mutex_unlock(&fbc->lock);
 658}
 659
 660static bool stride_is_valid(struct drm_i915_private *dev_priv,
 661			    unsigned int stride)
 662{
 663	/* These should have been caught earlier. */
 664	WARN_ON(stride < 512);
 665	WARN_ON((stride & (64 - 1)) != 0);
 666
 667	/* Below are the additional FBC restrictions. */
 668
 669	if (IS_GEN2(dev_priv) || IS_GEN3(dev_priv))
 670		return stride == 4096 || stride == 8192;
 671
 672	if (IS_GEN4(dev_priv) && !IS_G4X(dev_priv) && stride < 2048)
 673		return false;
 674
 675	if (stride > 16384)
 676		return false;
 677
 678	return true;
 679}
 680
 681static bool pixel_format_is_valid(struct drm_i915_private *dev_priv,
 682				  uint32_t pixel_format)
 683{
 684	switch (pixel_format) {
 685	case DRM_FORMAT_XRGB8888:
 686	case DRM_FORMAT_XBGR8888:
 687		return true;
 688	case DRM_FORMAT_XRGB1555:
 689	case DRM_FORMAT_RGB565:
 690		/* 16bpp not supported on gen2 */
 691		if (IS_GEN2(dev_priv))
 692			return false;
 693		/* WaFbcOnly1to1Ratio:ctg */
 694		if (IS_G4X(dev_priv))
 695			return false;
 696		return true;
 697	default:
 698		return false;
 699	}
 700}
 701
 702/*
 703 * For some reason, the hardware tracking starts looking at whatever we
 704 * programmed as the display plane base address register. It does not look at
 705 * the X and Y offset registers. That's why we look at the crtc->adjusted{x,y}
 706 * variables instead of just looking at the pipe/plane size.
 707 */
 708static bool intel_fbc_hw_tracking_covers_screen(struct intel_crtc *crtc)
 709{
 710	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 711	struct intel_fbc *fbc = &dev_priv->fbc;
 712	unsigned int effective_w, effective_h, max_w, max_h;
 713
 714	if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv)) {
 715		max_w = 4096;
 716		max_h = 4096;
 717	} else if (IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
 718		max_w = 4096;
 719		max_h = 2048;
 720	} else {
 721		max_w = 2048;
 722		max_h = 1536;
 723	}
 724
 725	intel_fbc_get_plane_source_size(&fbc->state_cache, &effective_w,
 726					&effective_h);
 727	effective_w += crtc->adjusted_x;
 728	effective_h += crtc->adjusted_y;
 729
 730	return effective_w <= max_w && effective_h <= max_h;
 731}
 732
 733static void intel_fbc_update_state_cache(struct intel_crtc *crtc,
 734					 struct intel_crtc_state *crtc_state,
 735					 struct intel_plane_state *plane_state)
 736{
 737	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 738	struct intel_fbc *fbc = &dev_priv->fbc;
 739	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 
 
 
 
 740	struct drm_framebuffer *fb = plane_state->base.fb;
 
 741
 742	cache->vma = NULL;
 
 743
 744	cache->crtc.mode_flags = crtc_state->base.adjusted_mode.flags;
 745	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 746		cache->crtc.hsw_bdw_pixel_rate =
 747			ilk_pipe_pixel_rate(crtc_state);
 748
 749	cache->plane.rotation = plane_state->base.rotation;
 750	cache->plane.src_w = drm_rect_width(&plane_state->base.src) >> 16;
 751	cache->plane.src_h = drm_rect_height(&plane_state->base.src) >> 16;
 752	cache->plane.visible = plane_state->base.visible;
 753
 754	if (!cache->plane.visible)
 755		return;
 756
 
 
 
 
 
 
 757	cache->fb.pixel_format = fb->pixel_format;
 758	cache->fb.stride = fb->pitches[0];
 759
 760	cache->vma = plane_state->vma;
 761}
 762
 763static bool intel_fbc_can_activate(struct intel_crtc *crtc)
 764{
 765	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 766	struct intel_fbc *fbc = &dev_priv->fbc;
 767	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 768
 769	/* We don't need to use a state cache here since this information is
 770	 * global for all CRTC.
 771	 */
 772	if (fbc->underrun_detected) {
 773		fbc->no_fbc_reason = "underrun detected";
 774		return false;
 775	}
 776
 777	if (!cache->vma) {
 778		fbc->no_fbc_reason = "primary plane not visible";
 779		return false;
 780	}
 781
 782	if ((cache->crtc.mode_flags & DRM_MODE_FLAG_INTERLACE) ||
 783	    (cache->crtc.mode_flags & DRM_MODE_FLAG_DBLSCAN)) {
 784		fbc->no_fbc_reason = "incompatible mode";
 785		return false;
 786	}
 787
 788	if (!intel_fbc_hw_tracking_covers_screen(crtc)) {
 789		fbc->no_fbc_reason = "mode too large for compression";
 790		return false;
 791	}
 792
 793	/* The use of a CPU fence is mandatory in order to detect writes
 794	 * by the CPU to the scanout and trigger updates to the FBC.
 795	 *
 796	 * Note that is possible for a tiled surface to be unmappable (and
 797	 * so have no fence associated with it) due to aperture constaints
 798	 * at the time of pinning.
 799	 */
 800	if (!cache->vma->fence) {
 
 801		fbc->no_fbc_reason = "framebuffer not tiled or fenced";
 802		return false;
 803	}
 804	if (INTEL_GEN(dev_priv) <= 4 && !IS_G4X(dev_priv) &&
 805	    cache->plane.rotation != DRM_ROTATE_0) {
 806		fbc->no_fbc_reason = "rotation unsupported";
 807		return false;
 808	}
 809
 810	if (!stride_is_valid(dev_priv, cache->fb.stride)) {
 811		fbc->no_fbc_reason = "framebuffer stride not supported";
 812		return false;
 813	}
 814
 815	if (!pixel_format_is_valid(dev_priv, cache->fb.pixel_format)) {
 816		fbc->no_fbc_reason = "pixel format is invalid";
 817		return false;
 818	}
 819
 820	/* WaFbcExceedCdClockThreshold:hsw,bdw */
 821	if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
 822	    cache->crtc.hsw_bdw_pixel_rate >= dev_priv->cdclk_freq * 95 / 100) {
 823		fbc->no_fbc_reason = "pixel rate is too big";
 824		return false;
 825	}
 826
 827	/* It is possible for the required CFB size change without a
 828	 * crtc->disable + crtc->enable since it is possible to change the
 829	 * stride without triggering a full modeset. Since we try to
 830	 * over-allocate the CFB, there's a chance we may keep FBC enabled even
 831	 * if this happens, but if we exceed the current CFB size we'll have to
 832	 * disable FBC. Notice that it would be possible to disable FBC, wait
 833	 * for a frame, free the stolen node, then try to reenable FBC in case
 834	 * we didn't get any invalidate/deactivate calls, but this would require
 835	 * a lot of tracking just for a specific case. If we conclude it's an
 836	 * important case, we can implement it later. */
 837	if (intel_fbc_calculate_cfb_size(dev_priv, &fbc->state_cache) >
 838	    fbc->compressed_fb.size * fbc->threshold) {
 839		fbc->no_fbc_reason = "CFB requirements changed";
 840		return false;
 841	}
 842
 843	return true;
 844}
 845
 846static bool intel_fbc_can_enable(struct drm_i915_private *dev_priv)
 847{
 
 848	struct intel_fbc *fbc = &dev_priv->fbc;
 
 
 849
 850	if (intel_vgpu_active(dev_priv)) {
 851		fbc->no_fbc_reason = "VGPU is active";
 852		return false;
 853	}
 854
 
 
 
 
 
 855	if (!i915.enable_fbc) {
 856		fbc->no_fbc_reason = "disabled per module param or by default";
 857		return false;
 858	}
 859
 860	if (fbc->underrun_detected) {
 861		fbc->no_fbc_reason = "underrun detected";
 
 
 
 
 
 862		return false;
 863	}
 864
 865	return true;
 866}
 867
 868static void intel_fbc_get_reg_params(struct intel_crtc *crtc,
 869				     struct intel_fbc_reg_params *params)
 870{
 871	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 872	struct intel_fbc *fbc = &dev_priv->fbc;
 873	struct intel_fbc_state_cache *cache = &fbc->state_cache;
 874
 875	/* Since all our fields are integer types, use memset here so the
 876	 * comparison function can rely on memcmp because the padding will be
 877	 * zero. */
 878	memset(params, 0, sizeof(*params));
 879
 880	params->vma = cache->vma;
 881
 882	params->crtc.pipe = crtc->pipe;
 883	params->crtc.plane = crtc->plane;
 884	params->crtc.fence_y_offset = get_crtc_fence_y_offset(crtc);
 885
 886	params->fb.pixel_format = cache->fb.pixel_format;
 887	params->fb.stride = cache->fb.stride;
 
 888
 889	params->cfb_size = intel_fbc_calculate_cfb_size(dev_priv, cache);
 
 
 890}
 891
 892static bool intel_fbc_reg_params_equal(struct intel_fbc_reg_params *params1,
 893				       struct intel_fbc_reg_params *params2)
 894{
 895	/* We can use this since intel_fbc_get_reg_params() does a memset. */
 896	return memcmp(params1, params2, sizeof(*params1)) == 0;
 897}
 898
 899void intel_fbc_pre_update(struct intel_crtc *crtc,
 900			  struct intel_crtc_state *crtc_state,
 901			  struct intel_plane_state *plane_state)
 902{
 903	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 904	struct intel_fbc *fbc = &dev_priv->fbc;
 905
 906	if (!fbc_supported(dev_priv))
 907		return;
 908
 909	mutex_lock(&fbc->lock);
 910
 911	if (!multiple_pipes_ok(crtc, plane_state)) {
 912		fbc->no_fbc_reason = "more than one pipe active";
 913		goto deactivate;
 914	}
 915
 916	if (!fbc->enabled || fbc->crtc != crtc)
 917		goto unlock;
 918
 919	intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
 920
 921deactivate:
 922	intel_fbc_deactivate(dev_priv);
 923unlock:
 924	mutex_unlock(&fbc->lock);
 925}
 926
 927static void __intel_fbc_post_update(struct intel_crtc *crtc)
 928{
 929	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 930	struct intel_fbc *fbc = &dev_priv->fbc;
 931	struct intel_fbc_reg_params old_params;
 932
 933	WARN_ON(!mutex_is_locked(&fbc->lock));
 934
 935	if (!fbc->enabled || fbc->crtc != crtc)
 936		return;
 937
 938	if (!intel_fbc_can_activate(crtc)) {
 939		WARN_ON(fbc->active);
 940		return;
 941	}
 942
 943	old_params = fbc->params;
 944	intel_fbc_get_reg_params(crtc, &fbc->params);
 945
 946	/* If the scanout has not changed, don't modify the FBC settings.
 947	 * Note that we make the fundamental assumption that the fb->obj
 948	 * cannot be unpinned (and have its GTT offset and fence revoked)
 949	 * without first being decoupled from the scanout and FBC disabled.
 950	 */
 951	if (fbc->active &&
 952	    intel_fbc_reg_params_equal(&old_params, &fbc->params))
 953		return;
 954
 955	intel_fbc_deactivate(dev_priv);
 956	intel_fbc_schedule_activation(crtc);
 957	fbc->no_fbc_reason = "FBC enabled (active or scheduled)";
 958}
 959
 960void intel_fbc_post_update(struct intel_crtc *crtc)
 961{
 962	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 963	struct intel_fbc *fbc = &dev_priv->fbc;
 964
 965	if (!fbc_supported(dev_priv))
 966		return;
 967
 968	mutex_lock(&fbc->lock);
 969	__intel_fbc_post_update(crtc);
 970	mutex_unlock(&fbc->lock);
 971}
 972
 973static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
 974{
 975	if (fbc->enabled)
 976		return to_intel_plane(fbc->crtc->base.primary)->frontbuffer_bit;
 977	else
 978		return fbc->possible_framebuffer_bits;
 979}
 980
 981void intel_fbc_invalidate(struct drm_i915_private *dev_priv,
 982			  unsigned int frontbuffer_bits,
 983			  enum fb_op_origin origin)
 984{
 985	struct intel_fbc *fbc = &dev_priv->fbc;
 986
 987	if (!fbc_supported(dev_priv))
 988		return;
 989
 990	if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
 991		return;
 992
 993	mutex_lock(&fbc->lock);
 994
 995	fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
 996
 997	if (fbc->enabled && fbc->busy_bits)
 998		intel_fbc_deactivate(dev_priv);
 999
1000	mutex_unlock(&fbc->lock);
1001}
1002
1003void intel_fbc_flush(struct drm_i915_private *dev_priv,
1004		     unsigned int frontbuffer_bits, enum fb_op_origin origin)
1005{
1006	struct intel_fbc *fbc = &dev_priv->fbc;
1007
1008	if (!fbc_supported(dev_priv))
1009		return;
1010
 
 
 
1011	mutex_lock(&fbc->lock);
1012
1013	fbc->busy_bits &= ~frontbuffer_bits;
1014
1015	if (origin == ORIGIN_GTT || origin == ORIGIN_FLIP)
1016		goto out;
1017
1018	if (!fbc->busy_bits && fbc->enabled &&
1019	    (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
1020		if (fbc->active)
1021			intel_fbc_recompress(dev_priv);
1022		else
1023			__intel_fbc_post_update(fbc->crtc);
1024	}
1025
1026out:
1027	mutex_unlock(&fbc->lock);
1028}
1029
1030/**
1031 * intel_fbc_choose_crtc - select a CRTC to enable FBC on
1032 * @dev_priv: i915 device instance
1033 * @state: the atomic state structure
1034 *
1035 * This function looks at the proposed state for CRTCs and planes, then chooses
1036 * which pipe is going to have FBC by setting intel_crtc_state->enable_fbc to
1037 * true.
1038 *
1039 * Later, intel_fbc_enable is going to look for state->enable_fbc and then maybe
1040 * enable FBC for the chosen CRTC. If it does, it will set dev_priv->fbc.crtc.
1041 */
1042void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv,
1043			   struct drm_atomic_state *state)
1044{
1045	struct intel_fbc *fbc = &dev_priv->fbc;
 
 
1046	struct drm_plane *plane;
1047	struct drm_plane_state *plane_state;
1048	bool crtc_chosen = false;
1049	int i;
1050
1051	mutex_lock(&fbc->lock);
1052
1053	/* Does this atomic commit involve the CRTC currently tied to FBC? */
1054	if (fbc->crtc &&
1055	    !drm_atomic_get_existing_crtc_state(state, &fbc->crtc->base))
1056		goto out;
1057
1058	if (!intel_fbc_can_enable(dev_priv))
 
 
1059		goto out;
1060
1061	/* Simply choose the first CRTC that is compatible and has a visible
1062	 * plane. We could go for fancier schemes such as checking the plane
1063	 * size, but this would just affect the few platforms that don't tie FBC
1064	 * to pipe or plane A. */
1065	for_each_plane_in_state(state, plane, plane_state, i) {
1066		struct intel_plane_state *intel_plane_state =
1067			to_intel_plane_state(plane_state);
1068		struct intel_crtc_state *intel_crtc_state;
1069		struct intel_crtc *crtc = to_intel_crtc(plane_state->crtc);
1070
1071		if (!intel_plane_state->base.visible)
1072			continue;
1073
1074		if (fbc_on_pipe_a_only(dev_priv) && crtc->pipe != PIPE_A)
1075			continue;
 
1076
1077		if (fbc_on_plane_a_only(dev_priv) && crtc->plane != PLANE_A)
1078			continue;
1079
1080		intel_crtc_state = to_intel_crtc_state(
1081			drm_atomic_get_existing_crtc_state(state, &crtc->base));
1082
1083		intel_crtc_state->enable_fbc = true;
1084		crtc_chosen = true;
1085		break;
1086	}
1087
1088	if (!crtc_chosen)
1089		fbc->no_fbc_reason = "no suitable CRTC for FBC";
1090
1091out:
1092	mutex_unlock(&fbc->lock);
1093}
1094
1095/**
1096 * intel_fbc_enable: tries to enable FBC on the CRTC
1097 * @crtc: the CRTC
1098 * @crtc_state: corresponding &drm_crtc_state for @crtc
1099 * @plane_state: corresponding &drm_plane_state for the primary plane of @crtc
1100 *
1101 * This function checks if the given CRTC was chosen for FBC, then enables it if
1102 * possible. Notice that it doesn't activate FBC. It is valid to call
1103 * intel_fbc_enable multiple times for the same pipe without an
1104 * intel_fbc_disable in the middle, as long as it is deactivated.
1105 */
1106void intel_fbc_enable(struct intel_crtc *crtc,
1107		      struct intel_crtc_state *crtc_state,
1108		      struct intel_plane_state *plane_state)
1109{
1110	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1111	struct intel_fbc *fbc = &dev_priv->fbc;
1112
1113	if (!fbc_supported(dev_priv))
1114		return;
1115
1116	mutex_lock(&fbc->lock);
1117
1118	if (fbc->enabled) {
1119		WARN_ON(fbc->crtc == NULL);
1120		if (fbc->crtc == crtc) {
1121			WARN_ON(!crtc_state->enable_fbc);
1122			WARN_ON(fbc->active);
1123		}
1124		goto out;
1125	}
1126
1127	if (!crtc_state->enable_fbc)
1128		goto out;
1129
1130	WARN_ON(fbc->active);
1131	WARN_ON(fbc->crtc != NULL);
1132
1133	intel_fbc_update_state_cache(crtc, crtc_state, plane_state);
1134	if (intel_fbc_alloc_cfb(crtc)) {
1135		fbc->no_fbc_reason = "not enough stolen memory";
1136		goto out;
1137	}
1138
1139	DRM_DEBUG_KMS("Enabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1140	fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1141
1142	fbc->enabled = true;
1143	fbc->crtc = crtc;
1144out:
1145	mutex_unlock(&fbc->lock);
1146}
1147
1148/**
1149 * __intel_fbc_disable - disable FBC
1150 * @dev_priv: i915 device instance
1151 *
1152 * This is the low level function that actually disables FBC. Callers should
1153 * grab the FBC lock.
1154 */
1155static void __intel_fbc_disable(struct drm_i915_private *dev_priv)
1156{
1157	struct intel_fbc *fbc = &dev_priv->fbc;
1158	struct intel_crtc *crtc = fbc->crtc;
1159
1160	WARN_ON(!mutex_is_locked(&fbc->lock));
1161	WARN_ON(!fbc->enabled);
1162	WARN_ON(fbc->active);
1163	WARN_ON(crtc->active);
1164
1165	DRM_DEBUG_KMS("Disabling FBC on pipe %c\n", pipe_name(crtc->pipe));
1166
1167	__intel_fbc_cleanup_cfb(dev_priv);
1168
1169	fbc->enabled = false;
1170	fbc->crtc = NULL;
1171}
1172
1173/**
1174 * intel_fbc_disable - disable FBC if it's associated with crtc
1175 * @crtc: the CRTC
1176 *
1177 * This function disables FBC if it's associated with the provided CRTC.
1178 */
1179void intel_fbc_disable(struct intel_crtc *crtc)
1180{
1181	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
1182	struct intel_fbc *fbc = &dev_priv->fbc;
1183
1184	if (!fbc_supported(dev_priv))
1185		return;
1186
1187	mutex_lock(&fbc->lock);
1188	if (fbc->crtc == crtc)
 
 
1189		__intel_fbc_disable(dev_priv);
 
1190	mutex_unlock(&fbc->lock);
1191
1192	cancel_work_sync(&fbc->work.work);
1193}
1194
1195/**
1196 * intel_fbc_global_disable - globally disable FBC
1197 * @dev_priv: i915 device instance
1198 *
1199 * This function disables FBC regardless of which CRTC is associated with it.
1200 */
1201void intel_fbc_global_disable(struct drm_i915_private *dev_priv)
1202{
1203	struct intel_fbc *fbc = &dev_priv->fbc;
1204
1205	if (!fbc_supported(dev_priv))
1206		return;
1207
1208	mutex_lock(&fbc->lock);
1209	if (fbc->enabled)
1210		__intel_fbc_disable(dev_priv);
1211	mutex_unlock(&fbc->lock);
1212
1213	cancel_work_sync(&fbc->work.work);
1214}
1215
1216static void intel_fbc_underrun_work_fn(struct work_struct *work)
1217{
1218	struct drm_i915_private *dev_priv =
1219		container_of(work, struct drm_i915_private, fbc.underrun_work);
1220	struct intel_fbc *fbc = &dev_priv->fbc;
1221
1222	mutex_lock(&fbc->lock);
1223
1224	/* Maybe we were scheduled twice. */
1225	if (fbc->underrun_detected)
1226		goto out;
1227
1228	DRM_DEBUG_KMS("Disabling FBC due to FIFO underrun.\n");
1229	fbc->underrun_detected = true;
1230
1231	intel_fbc_deactivate(dev_priv);
1232out:
1233	mutex_unlock(&fbc->lock);
1234}
1235
1236/**
1237 * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
1238 * @dev_priv: i915 device instance
1239 *
1240 * Without FBC, most underruns are harmless and don't really cause too many
1241 * problems, except for an annoying message on dmesg. With FBC, underruns can
1242 * become black screens or even worse, especially when paired with bad
1243 * watermarks. So in order for us to be on the safe side, completely disable FBC
1244 * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
1245 * already suggests that watermarks may be bad, so try to be as safe as
1246 * possible.
1247 *
1248 * This function is called from the IRQ handler.
1249 */
1250void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv)
1251{
1252	struct intel_fbc *fbc = &dev_priv->fbc;
1253
1254	if (!fbc_supported(dev_priv))
1255		return;
1256
1257	/* There's no guarantee that underrun_detected won't be set to true
1258	 * right after this check and before the work is scheduled, but that's
1259	 * not a problem since we'll check it again under the work function
1260	 * while FBC is locked. This check here is just to prevent us from
1261	 * unnecessarily scheduling the work, and it relies on the fact that we
1262	 * never switch underrun_detect back to false after it's true. */
1263	if (READ_ONCE(fbc->underrun_detected))
1264		return;
1265
1266	schedule_work(&fbc->underrun_work);
1267}
1268
1269/**
1270 * intel_fbc_init_pipe_state - initialize FBC's CRTC visibility tracking
1271 * @dev_priv: i915 device instance
1272 *
1273 * The FBC code needs to track CRTC visibility since the older platforms can't
1274 * have FBC enabled while multiple pipes are used. This function does the
1275 * initial setup at driver load to make sure FBC is matching the real hardware.
1276 */
1277void intel_fbc_init_pipe_state(struct drm_i915_private *dev_priv)
1278{
1279	struct intel_crtc *crtc;
1280
1281	/* Don't even bother tracking anything if we don't need. */
1282	if (!no_fbc_on_multiple_pipes(dev_priv))
1283		return;
1284
1285	for_each_intel_crtc(&dev_priv->drm, crtc)
1286		if (intel_crtc_active(crtc) &&
1287		    to_intel_plane_state(crtc->base.primary->state)->base.visible)
1288			dev_priv->fbc.visible_pipes_mask |= (1 << crtc->pipe);
1289}
1290
1291/*
1292 * The DDX driver changes its behavior depending on the value it reads from
1293 * i915.enable_fbc, so sanitize it by translating the default value into either
1294 * 0 or 1 in order to allow it to know what's going on.
1295 *
1296 * Notice that this is done at driver initialization and we still allow user
1297 * space to change the value during runtime without sanitizing it again. IGT
1298 * relies on being able to change i915.enable_fbc at runtime.
1299 */
1300static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv)
1301{
1302	if (i915.enable_fbc >= 0)
1303		return !!i915.enable_fbc;
1304
1305	if (!HAS_FBC(dev_priv))
1306		return 0;
1307
1308	if (IS_BROADWELL(dev_priv))
1309		return 1;
1310
1311	return 0;
1312}
1313
1314static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv)
1315{
1316#ifdef CONFIG_INTEL_IOMMU
1317	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
1318	if (intel_iommu_gfx_mapped &&
1319	    (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) {
1320		DRM_INFO("Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
1321		return true;
1322	}
1323#endif
1324
1325	return false;
1326}
1327
1328/**
1329 * intel_fbc_init - Initialize FBC
1330 * @dev_priv: the i915 device
1331 *
1332 * This function might be called during PM init process.
1333 */
1334void intel_fbc_init(struct drm_i915_private *dev_priv)
1335{
1336	struct intel_fbc *fbc = &dev_priv->fbc;
1337	enum pipe pipe;
1338
1339	INIT_WORK(&fbc->work.work, intel_fbc_work_fn);
1340	INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
1341	mutex_init(&fbc->lock);
1342	fbc->enabled = false;
1343	fbc->active = false;
1344	fbc->work.scheduled = false;
1345
1346	if (need_fbc_vtd_wa(dev_priv))
1347		mkwrite_device_info(dev_priv)->has_fbc = false;
1348
1349	i915.enable_fbc = intel_sanitize_fbc_option(dev_priv);
1350	DRM_DEBUG_KMS("Sanitized enable_fbc value: %d\n", i915.enable_fbc);
1351
1352	if (!HAS_FBC(dev_priv)) {
1353		fbc->no_fbc_reason = "unsupported by this chipset";
1354		return;
1355	}
1356
1357	for_each_pipe(dev_priv, pipe) {
1358		fbc->possible_framebuffer_bits |=
1359				INTEL_FRONTBUFFER_PRIMARY(pipe);
1360
1361		if (fbc_on_pipe_a_only(dev_priv))
1362			break;
1363	}
1364
1365	/* This value was pulled out of someone's hat */
1366	if (INTEL_GEN(dev_priv) <= 4 && !IS_GM45(dev_priv))
1367		I915_WRITE(FBC_CONTROL, 500 << FBC_CTL_INTERVAL_SHIFT);
1368
1369	/* We still don't have any sort of hardware state readout for FBC, so
1370	 * deactivate it in case the BIOS activated it to make sure software
1371	 * matches the hardware state. */
1372	if (intel_fbc_hw_is_active(dev_priv))
1373		intel_fbc_hw_deactivate(dev_priv);
1374}