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 <drm/drm_fourcc.h>
42 
43 #include "i915_drv.h"
44 #include "i915_vgpu.h"
45 #include "intel_cdclk.h"
46 #include "intel_de.h"
47 #include "intel_display_trace.h"
48 #include "intel_display_types.h"
49 #include "intel_fbc.h"
50 #include "intel_frontbuffer.h"
51 
52 #define for_each_fbc_id(__dev_priv, __fbc_id) \
53 	for ((__fbc_id) = INTEL_FBC_A; (__fbc_id) < I915_MAX_FBCS; (__fbc_id)++) \
54 		for_each_if(INTEL_INFO(__dev_priv)->display.fbc_mask & BIT(__fbc_id))
55 
56 #define for_each_intel_fbc(__dev_priv, __fbc, __fbc_id) \
57 	for_each_fbc_id((__dev_priv), (__fbc_id)) \
58 		for_each_if((__fbc) = (__dev_priv)->fbc[(__fbc_id)])
59 
60 struct intel_fbc_funcs {
61 	void (*activate)(struct intel_fbc *fbc);
62 	void (*deactivate)(struct intel_fbc *fbc);
63 	bool (*is_active)(struct intel_fbc *fbc);
64 	bool (*is_compressing)(struct intel_fbc *fbc);
65 	void (*nuke)(struct intel_fbc *fbc);
66 	void (*program_cfb)(struct intel_fbc *fbc);
67 	void (*set_false_color)(struct intel_fbc *fbc, bool enable);
68 };
69 
70 struct intel_fbc_state {
71 	struct intel_plane *plane;
72 	unsigned int cfb_stride;
73 	unsigned int cfb_size;
74 	unsigned int fence_y_offset;
75 	u16 override_cfb_stride;
76 	u16 interval;
77 	s8 fence_id;
78 };
79 
80 struct intel_fbc {
81 	struct drm_i915_private *i915;
82 	const struct intel_fbc_funcs *funcs;
83 
84 	/*
85 	 * This is always the inner lock when overlapping with
86 	 * struct_mutex and it's the outer lock when overlapping
87 	 * with stolen_lock.
88 	 */
89 	struct mutex lock;
90 	unsigned int possible_framebuffer_bits;
91 	unsigned int busy_bits;
92 
93 	struct drm_mm_node compressed_fb;
94 	struct drm_mm_node compressed_llb;
95 
96 	enum intel_fbc_id id;
97 
98 	u8 limit;
99 
100 	bool false_color;
101 
102 	bool active;
103 	bool activated;
104 	bool flip_pending;
105 
106 	bool underrun_detected;
107 	struct work_struct underrun_work;
108 
109 	/*
110 	 * This structure contains everything that's relevant to program the
111 	 * hardware registers. When we want to figure out if we need to disable
112 	 * and re-enable FBC for a new configuration we just check if there's
113 	 * something different in the struct. The genx_fbc_activate functions
114 	 * are supposed to read from it in order to program the registers.
115 	 */
116 	struct intel_fbc_state state;
117 	const char *no_fbc_reason;
118 };
119 
120 /* plane stride in pixels */
121 static unsigned int intel_fbc_plane_stride(const struct intel_plane_state *plane_state)
122 {
123 	const struct drm_framebuffer *fb = plane_state->hw.fb;
124 	unsigned int stride;
125 
126 	stride = plane_state->view.color_plane[0].mapping_stride;
127 	if (!drm_rotation_90_or_270(plane_state->hw.rotation))
128 		stride /= fb->format->cpp[0];
129 
130 	return stride;
131 }
132 
133 /* plane stride based cfb stride in bytes, assuming 1:1 compression limit */
134 static unsigned int _intel_fbc_cfb_stride(const struct intel_plane_state *plane_state)
135 {
136 	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
137 
138 	return intel_fbc_plane_stride(plane_state) * cpp;
139 }
140 
141 /* minimum acceptable cfb stride in bytes, assuming 1:1 compression limit */
142 static unsigned int skl_fbc_min_cfb_stride(const struct intel_plane_state *plane_state)
143 {
144 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
145 	unsigned int limit = 4; /* 1:4 compression limit is the worst case */
146 	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
147 	unsigned int width = drm_rect_width(&plane_state->uapi.src) >> 16;
148 	unsigned int height = 4; /* FBC segment is 4 lines */
149 	unsigned int stride;
150 
151 	/* minimum segment stride we can use */
152 	stride = width * cpp * height / limit;
153 
154 	/*
155 	 * Wa_16011863758: icl+
156 	 * Avoid some hardware segment address miscalculation.
157 	 */
158 	if (DISPLAY_VER(i915) >= 11)
159 		stride += 64;
160 
161 	/*
162 	 * At least some of the platforms require each 4 line segment to
163 	 * be 512 byte aligned. Just do it always for simplicity.
164 	 */
165 	stride = ALIGN(stride, 512);
166 
167 	/* convert back to single line equivalent with 1:1 compression limit */
168 	return stride * limit / height;
169 }
170 
171 /* properly aligned cfb stride in bytes, assuming 1:1 compression limit */
172 static unsigned int intel_fbc_cfb_stride(const struct intel_plane_state *plane_state)
173 {
174 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
175 	unsigned int stride = _intel_fbc_cfb_stride(plane_state);
176 
177 	/*
178 	 * At least some of the platforms require each 4 line segment to
179 	 * be 512 byte aligned. Aligning each line to 512 bytes guarantees
180 	 * that regardless of the compression limit we choose later.
181 	 */
182 	if (DISPLAY_VER(i915) >= 9)
183 		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(plane_state));
184 	else
185 		return stride;
186 }
187 
188 static unsigned int intel_fbc_cfb_size(const struct intel_plane_state *plane_state)
189 {
190 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
191 	int lines = drm_rect_height(&plane_state->uapi.src) >> 16;
192 
193 	if (DISPLAY_VER(i915) == 7)
194 		lines = min(lines, 2048);
195 	else if (DISPLAY_VER(i915) >= 8)
196 		lines = min(lines, 2560);
197 
198 	return lines * intel_fbc_cfb_stride(plane_state);
199 }
200 
201 static u16 intel_fbc_override_cfb_stride(const struct intel_plane_state *plane_state)
202 {
203 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
204 	unsigned int stride_aligned = intel_fbc_cfb_stride(plane_state);
205 	unsigned int stride = _intel_fbc_cfb_stride(plane_state);
206 	const struct drm_framebuffer *fb = plane_state->hw.fb;
207 
208 	/*
209 	 * Override stride in 64 byte units per 4 line segment.
210 	 *
211 	 * Gen9 hw miscalculates cfb stride for linear as
212 	 * PLANE_STRIDE*512 instead of PLANE_STRIDE*64, so
213 	 * we always need to use the override there.
214 	 */
215 	if (stride != stride_aligned ||
216 	    (DISPLAY_VER(i915) == 9 && fb->modifier == DRM_FORMAT_MOD_LINEAR))
217 		return stride_aligned * 4 / 64;
218 
219 	return 0;
220 }
221 
222 static u32 i8xx_fbc_ctl(struct intel_fbc *fbc)
223 {
224 	const struct intel_fbc_state *fbc_state = &fbc->state;
225 	struct drm_i915_private *i915 = fbc->i915;
226 	unsigned int cfb_stride;
227 	u32 fbc_ctl;
228 
229 	cfb_stride = fbc_state->cfb_stride / fbc->limit;
230 
231 	/* FBC_CTL wants 32B or 64B units */
232 	if (DISPLAY_VER(i915) == 2)
233 		cfb_stride = (cfb_stride / 32) - 1;
234 	else
235 		cfb_stride = (cfb_stride / 64) - 1;
236 
237 	fbc_ctl = FBC_CTL_PERIODIC |
238 		FBC_CTL_INTERVAL(fbc_state->interval) |
239 		FBC_CTL_STRIDE(cfb_stride);
240 
241 	if (IS_I945GM(i915))
242 		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
243 
244 	if (fbc_state->fence_id >= 0)
245 		fbc_ctl |= FBC_CTL_FENCENO(fbc_state->fence_id);
246 
247 	return fbc_ctl;
248 }
249 
250 static u32 i965_fbc_ctl2(struct intel_fbc *fbc)
251 {
252 	const struct intel_fbc_state *fbc_state = &fbc->state;
253 	u32 fbc_ctl2;
254 
255 	fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM |
256 		FBC_CTL_PLANE(fbc_state->plane->i9xx_plane);
257 
258 	if (fbc_state->fence_id >= 0)
259 		fbc_ctl2 |= FBC_CTL_CPU_FENCE_EN;
260 
261 	return fbc_ctl2;
262 }
263 
264 static void i8xx_fbc_deactivate(struct intel_fbc *fbc)
265 {
266 	struct drm_i915_private *i915 = fbc->i915;
267 	u32 fbc_ctl;
268 
269 	/* Disable compression */
270 	fbc_ctl = intel_de_read(i915, FBC_CONTROL);
271 	if ((fbc_ctl & FBC_CTL_EN) == 0)
272 		return;
273 
274 	fbc_ctl &= ~FBC_CTL_EN;
275 	intel_de_write(i915, FBC_CONTROL, fbc_ctl);
276 
277 	/* Wait for compressing bit to clear */
278 	if (intel_de_wait_for_clear(i915, FBC_STATUS,
279 				    FBC_STAT_COMPRESSING, 10)) {
280 		drm_dbg_kms(&i915->drm, "FBC idle timed out\n");
281 		return;
282 	}
283 }
284 
285 static void i8xx_fbc_activate(struct intel_fbc *fbc)
286 {
287 	const struct intel_fbc_state *fbc_state = &fbc->state;
288 	struct drm_i915_private *i915 = fbc->i915;
289 	int i;
290 
291 	/* Clear old tags */
292 	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
293 		intel_de_write(i915, FBC_TAG(i), 0);
294 
295 	if (DISPLAY_VER(i915) == 4) {
296 		intel_de_write(i915, FBC_CONTROL2,
297 			       i965_fbc_ctl2(fbc));
298 		intel_de_write(i915, FBC_FENCE_OFF,
299 			       fbc_state->fence_y_offset);
300 	}
301 
302 	intel_de_write(i915, FBC_CONTROL,
303 		       FBC_CTL_EN | i8xx_fbc_ctl(fbc));
304 }
305 
306 static bool i8xx_fbc_is_active(struct intel_fbc *fbc)
307 {
308 	return intel_de_read(fbc->i915, FBC_CONTROL) & FBC_CTL_EN;
309 }
310 
311 static bool i8xx_fbc_is_compressing(struct intel_fbc *fbc)
312 {
313 	return intel_de_read(fbc->i915, FBC_STATUS) &
314 		(FBC_STAT_COMPRESSING | FBC_STAT_COMPRESSED);
315 }
316 
317 static void i8xx_fbc_nuke(struct intel_fbc *fbc)
318 {
319 	struct intel_fbc_state *fbc_state = &fbc->state;
320 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
321 	struct drm_i915_private *dev_priv = fbc->i915;
322 
323 	spin_lock_irq(&dev_priv->uncore.lock);
324 	intel_de_write_fw(dev_priv, DSPADDR(i9xx_plane),
325 			  intel_de_read_fw(dev_priv, DSPADDR(i9xx_plane)));
326 	spin_unlock_irq(&dev_priv->uncore.lock);
327 }
328 
329 static void i8xx_fbc_program_cfb(struct intel_fbc *fbc)
330 {
331 	struct drm_i915_private *i915 = fbc->i915;
332 
333 	GEM_BUG_ON(range_overflows_end_t(u64, i915->dsm.start,
334 					 fbc->compressed_fb.start, U32_MAX));
335 	GEM_BUG_ON(range_overflows_end_t(u64, i915->dsm.start,
336 					 fbc->compressed_llb.start, U32_MAX));
337 
338 	intel_de_write(i915, FBC_CFB_BASE,
339 		       i915->dsm.start + fbc->compressed_fb.start);
340 	intel_de_write(i915, FBC_LL_BASE,
341 		       i915->dsm.start + fbc->compressed_llb.start);
342 }
343 
344 static const struct intel_fbc_funcs i8xx_fbc_funcs = {
345 	.activate = i8xx_fbc_activate,
346 	.deactivate = i8xx_fbc_deactivate,
347 	.is_active = i8xx_fbc_is_active,
348 	.is_compressing = i8xx_fbc_is_compressing,
349 	.nuke = i8xx_fbc_nuke,
350 	.program_cfb = i8xx_fbc_program_cfb,
351 };
352 
353 static void i965_fbc_nuke(struct intel_fbc *fbc)
354 {
355 	struct intel_fbc_state *fbc_state = &fbc->state;
356 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
357 	struct drm_i915_private *dev_priv = fbc->i915;
358 
359 	spin_lock_irq(&dev_priv->uncore.lock);
360 	intel_de_write_fw(dev_priv, DSPSURF(i9xx_plane),
361 			  intel_de_read_fw(dev_priv, DSPSURF(i9xx_plane)));
362 	spin_unlock_irq(&dev_priv->uncore.lock);
363 }
364 
365 static const struct intel_fbc_funcs i965_fbc_funcs = {
366 	.activate = i8xx_fbc_activate,
367 	.deactivate = i8xx_fbc_deactivate,
368 	.is_active = i8xx_fbc_is_active,
369 	.is_compressing = i8xx_fbc_is_compressing,
370 	.nuke = i965_fbc_nuke,
371 	.program_cfb = i8xx_fbc_program_cfb,
372 };
373 
374 static u32 g4x_dpfc_ctl_limit(struct intel_fbc *fbc)
375 {
376 	switch (fbc->limit) {
377 	default:
378 		MISSING_CASE(fbc->limit);
379 		fallthrough;
380 	case 1:
381 		return DPFC_CTL_LIMIT_1X;
382 	case 2:
383 		return DPFC_CTL_LIMIT_2X;
384 	case 4:
385 		return DPFC_CTL_LIMIT_4X;
386 	}
387 }
388 
389 static u32 g4x_dpfc_ctl(struct intel_fbc *fbc)
390 {
391 	const struct intel_fbc_state *fbc_state = &fbc->state;
392 	struct drm_i915_private *i915 = fbc->i915;
393 	u32 dpfc_ctl;
394 
395 	dpfc_ctl = g4x_dpfc_ctl_limit(fbc) |
396 		DPFC_CTL_PLANE_G4X(fbc_state->plane->i9xx_plane);
397 
398 	if (IS_G4X(i915))
399 		dpfc_ctl |= DPFC_CTL_SR_EN;
400 
401 	if (fbc_state->fence_id >= 0) {
402 		dpfc_ctl |= DPFC_CTL_FENCE_EN_G4X;
403 
404 		if (DISPLAY_VER(i915) < 6)
405 			dpfc_ctl |= DPFC_CTL_FENCENO(fbc_state->fence_id);
406 	}
407 
408 	return dpfc_ctl;
409 }
410 
411 static void g4x_fbc_activate(struct intel_fbc *fbc)
412 {
413 	const struct intel_fbc_state *fbc_state = &fbc->state;
414 	struct drm_i915_private *i915 = fbc->i915;
415 
416 	intel_de_write(i915, DPFC_FENCE_YOFF,
417 		       fbc_state->fence_y_offset);
418 
419 	intel_de_write(i915, DPFC_CONTROL,
420 		       DPFC_CTL_EN | g4x_dpfc_ctl(fbc));
421 }
422 
423 static void g4x_fbc_deactivate(struct intel_fbc *fbc)
424 {
425 	struct drm_i915_private *i915 = fbc->i915;
426 	u32 dpfc_ctl;
427 
428 	/* Disable compression */
429 	dpfc_ctl = intel_de_read(i915, DPFC_CONTROL);
430 	if (dpfc_ctl & DPFC_CTL_EN) {
431 		dpfc_ctl &= ~DPFC_CTL_EN;
432 		intel_de_write(i915, DPFC_CONTROL, dpfc_ctl);
433 	}
434 }
435 
436 static bool g4x_fbc_is_active(struct intel_fbc *fbc)
437 {
438 	return intel_de_read(fbc->i915, DPFC_CONTROL) & DPFC_CTL_EN;
439 }
440 
441 static bool g4x_fbc_is_compressing(struct intel_fbc *fbc)
442 {
443 	return intel_de_read(fbc->i915, DPFC_STATUS) & DPFC_COMP_SEG_MASK;
444 }
445 
446 static void g4x_fbc_program_cfb(struct intel_fbc *fbc)
447 {
448 	struct drm_i915_private *i915 = fbc->i915;
449 
450 	intel_de_write(i915, DPFC_CB_BASE, fbc->compressed_fb.start);
451 }
452 
453 static const struct intel_fbc_funcs g4x_fbc_funcs = {
454 	.activate = g4x_fbc_activate,
455 	.deactivate = g4x_fbc_deactivate,
456 	.is_active = g4x_fbc_is_active,
457 	.is_compressing = g4x_fbc_is_compressing,
458 	.nuke = i965_fbc_nuke,
459 	.program_cfb = g4x_fbc_program_cfb,
460 };
461 
462 static void ilk_fbc_activate(struct intel_fbc *fbc)
463 {
464 	struct intel_fbc_state *fbc_state = &fbc->state;
465 	struct drm_i915_private *i915 = fbc->i915;
466 
467 	intel_de_write(i915, ILK_DPFC_FENCE_YOFF(fbc->id),
468 		       fbc_state->fence_y_offset);
469 
470 	intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id),
471 		       DPFC_CTL_EN | g4x_dpfc_ctl(fbc));
472 }
473 
474 static void ilk_fbc_deactivate(struct intel_fbc *fbc)
475 {
476 	struct drm_i915_private *i915 = fbc->i915;
477 	u32 dpfc_ctl;
478 
479 	/* Disable compression */
480 	dpfc_ctl = intel_de_read(i915, ILK_DPFC_CONTROL(fbc->id));
481 	if (dpfc_ctl & DPFC_CTL_EN) {
482 		dpfc_ctl &= ~DPFC_CTL_EN;
483 		intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id), dpfc_ctl);
484 	}
485 }
486 
487 static bool ilk_fbc_is_active(struct intel_fbc *fbc)
488 {
489 	return intel_de_read(fbc->i915, ILK_DPFC_CONTROL(fbc->id)) & DPFC_CTL_EN;
490 }
491 
492 static bool ilk_fbc_is_compressing(struct intel_fbc *fbc)
493 {
494 	return intel_de_read(fbc->i915, ILK_DPFC_STATUS(fbc->id)) & DPFC_COMP_SEG_MASK;
495 }
496 
497 static void ilk_fbc_program_cfb(struct intel_fbc *fbc)
498 {
499 	struct drm_i915_private *i915 = fbc->i915;
500 
501 	intel_de_write(i915, ILK_DPFC_CB_BASE(fbc->id), fbc->compressed_fb.start);
502 }
503 
504 static const struct intel_fbc_funcs ilk_fbc_funcs = {
505 	.activate = ilk_fbc_activate,
506 	.deactivate = ilk_fbc_deactivate,
507 	.is_active = ilk_fbc_is_active,
508 	.is_compressing = ilk_fbc_is_compressing,
509 	.nuke = i965_fbc_nuke,
510 	.program_cfb = ilk_fbc_program_cfb,
511 };
512 
513 static void snb_fbc_program_fence(struct intel_fbc *fbc)
514 {
515 	const struct intel_fbc_state *fbc_state = &fbc->state;
516 	struct drm_i915_private *i915 = fbc->i915;
517 	u32 ctl = 0;
518 
519 	if (fbc_state->fence_id >= 0)
520 		ctl = SNB_DPFC_FENCE_EN | SNB_DPFC_FENCENO(fbc_state->fence_id);
521 
522 	intel_de_write(i915, SNB_DPFC_CTL_SA, ctl);
523 	intel_de_write(i915, SNB_DPFC_CPU_FENCE_OFFSET, fbc_state->fence_y_offset);
524 }
525 
526 static void snb_fbc_activate(struct intel_fbc *fbc)
527 {
528 	snb_fbc_program_fence(fbc);
529 
530 	ilk_fbc_activate(fbc);
531 }
532 
533 static void snb_fbc_nuke(struct intel_fbc *fbc)
534 {
535 	struct drm_i915_private *i915 = fbc->i915;
536 
537 	intel_de_write(i915, MSG_FBC_REND_STATE(fbc->id), FBC_REND_NUKE);
538 	intel_de_posting_read(i915, MSG_FBC_REND_STATE(fbc->id));
539 }
540 
541 static const struct intel_fbc_funcs snb_fbc_funcs = {
542 	.activate = snb_fbc_activate,
543 	.deactivate = ilk_fbc_deactivate,
544 	.is_active = ilk_fbc_is_active,
545 	.is_compressing = ilk_fbc_is_compressing,
546 	.nuke = snb_fbc_nuke,
547 	.program_cfb = ilk_fbc_program_cfb,
548 };
549 
550 static void glk_fbc_program_cfb_stride(struct intel_fbc *fbc)
551 {
552 	const struct intel_fbc_state *fbc_state = &fbc->state;
553 	struct drm_i915_private *i915 = fbc->i915;
554 	u32 val = 0;
555 
556 	if (fbc_state->override_cfb_stride)
557 		val |= FBC_STRIDE_OVERRIDE |
558 			FBC_STRIDE(fbc_state->override_cfb_stride / fbc->limit);
559 
560 	intel_de_write(i915, GLK_FBC_STRIDE(fbc->id), val);
561 }
562 
563 static void skl_fbc_program_cfb_stride(struct intel_fbc *fbc)
564 {
565 	const struct intel_fbc_state *fbc_state = &fbc->state;
566 	struct drm_i915_private *i915 = fbc->i915;
567 	u32 val = 0;
568 
569 	/* Display WA #0529: skl, kbl, bxt. */
570 	if (fbc_state->override_cfb_stride)
571 		val |= CHICKEN_FBC_STRIDE_OVERRIDE |
572 			CHICKEN_FBC_STRIDE(fbc_state->override_cfb_stride / fbc->limit);
573 
574 	intel_de_rmw(i915, CHICKEN_MISC_4,
575 		     CHICKEN_FBC_STRIDE_OVERRIDE |
576 		     CHICKEN_FBC_STRIDE_MASK, val);
577 }
578 
579 static u32 ivb_dpfc_ctl(struct intel_fbc *fbc)
580 {
581 	const struct intel_fbc_state *fbc_state = &fbc->state;
582 	struct drm_i915_private *i915 = fbc->i915;
583 	u32 dpfc_ctl;
584 
585 	dpfc_ctl = g4x_dpfc_ctl_limit(fbc);
586 
587 	if (IS_IVYBRIDGE(i915))
588 		dpfc_ctl |= DPFC_CTL_PLANE_IVB(fbc_state->plane->i9xx_plane);
589 
590 	if (fbc_state->fence_id >= 0)
591 		dpfc_ctl |= DPFC_CTL_FENCE_EN_IVB;
592 
593 	if (fbc->false_color)
594 		dpfc_ctl |= DPFC_CTL_FALSE_COLOR;
595 
596 	return dpfc_ctl;
597 }
598 
599 static void ivb_fbc_activate(struct intel_fbc *fbc)
600 {
601 	struct drm_i915_private *i915 = fbc->i915;
602 
603 	if (DISPLAY_VER(i915) >= 10)
604 		glk_fbc_program_cfb_stride(fbc);
605 	else if (DISPLAY_VER(i915) == 9)
606 		skl_fbc_program_cfb_stride(fbc);
607 
608 	if (to_gt(i915)->ggtt->num_fences)
609 		snb_fbc_program_fence(fbc);
610 
611 	intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id),
612 		       DPFC_CTL_EN | ivb_dpfc_ctl(fbc));
613 }
614 
615 static bool ivb_fbc_is_compressing(struct intel_fbc *fbc)
616 {
617 	return intel_de_read(fbc->i915, ILK_DPFC_STATUS2(fbc->id)) & DPFC_COMP_SEG_MASK_IVB;
618 }
619 
620 static void ivb_fbc_set_false_color(struct intel_fbc *fbc,
621 				    bool enable)
622 {
623 	intel_de_rmw(fbc->i915, ILK_DPFC_CONTROL(fbc->id),
624 		     DPFC_CTL_FALSE_COLOR, enable ? DPFC_CTL_FALSE_COLOR : 0);
625 }
626 
627 static const struct intel_fbc_funcs ivb_fbc_funcs = {
628 	.activate = ivb_fbc_activate,
629 	.deactivate = ilk_fbc_deactivate,
630 	.is_active = ilk_fbc_is_active,
631 	.is_compressing = ivb_fbc_is_compressing,
632 	.nuke = snb_fbc_nuke,
633 	.program_cfb = ilk_fbc_program_cfb,
634 	.set_false_color = ivb_fbc_set_false_color,
635 };
636 
637 static bool intel_fbc_hw_is_active(struct intel_fbc *fbc)
638 {
639 	return fbc->funcs->is_active(fbc);
640 }
641 
642 static void intel_fbc_hw_activate(struct intel_fbc *fbc)
643 {
644 	trace_intel_fbc_activate(fbc->state.plane);
645 
646 	fbc->active = true;
647 	fbc->activated = true;
648 
649 	fbc->funcs->activate(fbc);
650 }
651 
652 static void intel_fbc_hw_deactivate(struct intel_fbc *fbc)
653 {
654 	trace_intel_fbc_deactivate(fbc->state.plane);
655 
656 	fbc->active = false;
657 
658 	fbc->funcs->deactivate(fbc);
659 }
660 
661 static bool intel_fbc_is_compressing(struct intel_fbc *fbc)
662 {
663 	return fbc->funcs->is_compressing(fbc);
664 }
665 
666 static void intel_fbc_nuke(struct intel_fbc *fbc)
667 {
668 	trace_intel_fbc_nuke(fbc->state.plane);
669 
670 	fbc->funcs->nuke(fbc);
671 }
672 
673 static void intel_fbc_activate(struct intel_fbc *fbc)
674 {
675 	intel_fbc_hw_activate(fbc);
676 	intel_fbc_nuke(fbc);
677 
678 	fbc->no_fbc_reason = NULL;
679 }
680 
681 static void intel_fbc_deactivate(struct intel_fbc *fbc, const char *reason)
682 {
683 	struct drm_i915_private *i915 = fbc->i915;
684 
685 	drm_WARN_ON(&i915->drm, !mutex_is_locked(&fbc->lock));
686 
687 	if (fbc->active)
688 		intel_fbc_hw_deactivate(fbc);
689 
690 	fbc->no_fbc_reason = reason;
691 }
692 
693 static u64 intel_fbc_cfb_base_max(struct drm_i915_private *i915)
694 {
695 	if (DISPLAY_VER(i915) >= 5 || IS_G4X(i915))
696 		return BIT_ULL(28);
697 	else
698 		return BIT_ULL(32);
699 }
700 
701 static u64 intel_fbc_stolen_end(struct drm_i915_private *i915)
702 {
703 	u64 end;
704 
705 	/* The FBC hardware for BDW/SKL doesn't have access to the stolen
706 	 * reserved range size, so it always assumes the maximum (8mb) is used.
707 	 * If we enable FBC using a CFB on that memory range we'll get FIFO
708 	 * underruns, even if that range is not reserved by the BIOS. */
709 	if (IS_BROADWELL(i915) ||
710 	    (DISPLAY_VER(i915) == 9 && !IS_BROXTON(i915)))
711 		end = resource_size(&i915->dsm) - 8 * 1024 * 1024;
712 	else
713 		end = U64_MAX;
714 
715 	return min(end, intel_fbc_cfb_base_max(i915));
716 }
717 
718 static int intel_fbc_min_limit(const struct intel_plane_state *plane_state)
719 {
720 	return plane_state->hw.fb->format->cpp[0] == 2 ? 2 : 1;
721 }
722 
723 static int intel_fbc_max_limit(struct drm_i915_private *i915)
724 {
725 	/* WaFbcOnly1to1Ratio:ctg */
726 	if (IS_G4X(i915))
727 		return 1;
728 
729 	/*
730 	 * FBC2 can only do 1:1, 1:2, 1:4, we limit
731 	 * FBC1 to the same out of convenience.
732 	 */
733 	return 4;
734 }
735 
736 static int find_compression_limit(struct intel_fbc *fbc,
737 				  unsigned int size, int min_limit)
738 {
739 	struct drm_i915_private *i915 = fbc->i915;
740 	u64 end = intel_fbc_stolen_end(i915);
741 	int ret, limit = min_limit;
742 
743 	size /= limit;
744 
745 	/* Try to over-allocate to reduce reallocations and fragmentation. */
746 	ret = i915_gem_stolen_insert_node_in_range(i915, &fbc->compressed_fb,
747 						   size <<= 1, 4096, 0, end);
748 	if (ret == 0)
749 		return limit;
750 
751 	for (; limit <= intel_fbc_max_limit(i915); limit <<= 1) {
752 		ret = i915_gem_stolen_insert_node_in_range(i915, &fbc->compressed_fb,
753 							   size >>= 1, 4096, 0, end);
754 		if (ret == 0)
755 			return limit;
756 	}
757 
758 	return 0;
759 }
760 
761 static int intel_fbc_alloc_cfb(struct intel_fbc *fbc,
762 			       unsigned int size, int min_limit)
763 {
764 	struct drm_i915_private *i915 = fbc->i915;
765 	int ret;
766 
767 	drm_WARN_ON(&i915->drm,
768 		    drm_mm_node_allocated(&fbc->compressed_fb));
769 	drm_WARN_ON(&i915->drm,
770 		    drm_mm_node_allocated(&fbc->compressed_llb));
771 
772 	if (DISPLAY_VER(i915) < 5 && !IS_G4X(i915)) {
773 		ret = i915_gem_stolen_insert_node(i915, &fbc->compressed_llb,
774 						  4096, 4096);
775 		if (ret)
776 			goto err;
777 	}
778 
779 	ret = find_compression_limit(fbc, size, min_limit);
780 	if (!ret)
781 		goto err_llb;
782 	else if (ret > min_limit)
783 		drm_info_once(&i915->drm,
784 			      "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");
785 
786 	fbc->limit = ret;
787 
788 	drm_dbg_kms(&i915->drm,
789 		    "reserved %llu bytes of contiguous stolen space for FBC, limit: %d\n",
790 		    fbc->compressed_fb.size, fbc->limit);
791 
792 	return 0;
793 
794 err_llb:
795 	if (drm_mm_node_allocated(&fbc->compressed_llb))
796 		i915_gem_stolen_remove_node(i915, &fbc->compressed_llb);
797 err:
798 	if (drm_mm_initialized(&i915->mm.stolen))
799 		drm_info_once(&i915->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);
800 	return -ENOSPC;
801 }
802 
803 static void intel_fbc_program_cfb(struct intel_fbc *fbc)
804 {
805 	fbc->funcs->program_cfb(fbc);
806 }
807 
808 static void __intel_fbc_cleanup_cfb(struct intel_fbc *fbc)
809 {
810 	struct drm_i915_private *i915 = fbc->i915;
811 
812 	if (WARN_ON(intel_fbc_hw_is_active(fbc)))
813 		return;
814 
815 	if (drm_mm_node_allocated(&fbc->compressed_llb))
816 		i915_gem_stolen_remove_node(i915, &fbc->compressed_llb);
817 	if (drm_mm_node_allocated(&fbc->compressed_fb))
818 		i915_gem_stolen_remove_node(i915, &fbc->compressed_fb);
819 }
820 
821 void intel_fbc_cleanup(struct drm_i915_private *i915)
822 {
823 	struct intel_fbc *fbc;
824 	enum intel_fbc_id fbc_id;
825 
826 	for_each_intel_fbc(i915, fbc, fbc_id) {
827 		mutex_lock(&fbc->lock);
828 		__intel_fbc_cleanup_cfb(fbc);
829 		mutex_unlock(&fbc->lock);
830 
831 		kfree(fbc);
832 	}
833 }
834 
835 static bool stride_is_valid(const struct intel_plane_state *plane_state)
836 {
837 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
838 	const struct drm_framebuffer *fb = plane_state->hw.fb;
839 	unsigned int stride = intel_fbc_plane_stride(plane_state) *
840 		fb->format->cpp[0];
841 
842 	/* This should have been caught earlier. */
843 	if (drm_WARN_ON_ONCE(&i915->drm, (stride & (64 - 1)) != 0))
844 		return false;
845 
846 	/* Below are the additional FBC restrictions. */
847 	if (stride < 512)
848 		return false;
849 
850 	if (DISPLAY_VER(i915) == 2 || DISPLAY_VER(i915) == 3)
851 		return stride == 4096 || stride == 8192;
852 
853 	if (DISPLAY_VER(i915) == 4 && !IS_G4X(i915) && stride < 2048)
854 		return false;
855 
856 	/* Display WA #1105: skl,bxt,kbl,cfl,glk */
857 	if ((DISPLAY_VER(i915) == 9 || IS_GEMINILAKE(i915)) &&
858 	    fb->modifier == DRM_FORMAT_MOD_LINEAR && stride & 511)
859 		return false;
860 
861 	if (stride > 16384)
862 		return false;
863 
864 	return true;
865 }
866 
867 static bool pixel_format_is_valid(const struct intel_plane_state *plane_state)
868 {
869 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
870 	const struct drm_framebuffer *fb = plane_state->hw.fb;
871 
872 	switch (fb->format->format) {
873 	case DRM_FORMAT_XRGB8888:
874 	case DRM_FORMAT_XBGR8888:
875 		return true;
876 	case DRM_FORMAT_XRGB1555:
877 	case DRM_FORMAT_RGB565:
878 		/* 16bpp not supported on gen2 */
879 		if (DISPLAY_VER(i915) == 2)
880 			return false;
881 		/* WaFbcOnly1to1Ratio:ctg */
882 		if (IS_G4X(i915))
883 			return false;
884 		return true;
885 	default:
886 		return false;
887 	}
888 }
889 
890 static bool rotation_is_valid(const struct intel_plane_state *plane_state)
891 {
892 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
893 	const struct drm_framebuffer *fb = plane_state->hw.fb;
894 	unsigned int rotation = plane_state->hw.rotation;
895 
896 	if (DISPLAY_VER(i915) >= 9 && fb->format->format == DRM_FORMAT_RGB565 &&
897 	    drm_rotation_90_or_270(rotation))
898 		return false;
899 	else if (DISPLAY_VER(i915) <= 4 && !IS_G4X(i915) &&
900 		 rotation != DRM_MODE_ROTATE_0)
901 		return false;
902 
903 	return true;
904 }
905 
906 /*
907  * For some reason, the hardware tracking starts looking at whatever we
908  * programmed as the display plane base address register. It does not look at
909  * the X and Y offset registers. That's why we include the src x/y offsets
910  * instead of just looking at the plane size.
911  */
912 static bool intel_fbc_hw_tracking_covers_screen(const struct intel_plane_state *plane_state)
913 {
914 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
915 	unsigned int effective_w, effective_h, max_w, max_h;
916 
917 	if (DISPLAY_VER(i915) >= 10) {
918 		max_w = 5120;
919 		max_h = 4096;
920 	} else if (DISPLAY_VER(i915) >= 8 || IS_HASWELL(i915)) {
921 		max_w = 4096;
922 		max_h = 4096;
923 	} else if (IS_G4X(i915) || DISPLAY_VER(i915) >= 5) {
924 		max_w = 4096;
925 		max_h = 2048;
926 	} else {
927 		max_w = 2048;
928 		max_h = 1536;
929 	}
930 
931 	effective_w = plane_state->view.color_plane[0].x +
932 		(drm_rect_width(&plane_state->uapi.src) >> 16);
933 	effective_h = plane_state->view.color_plane[0].y +
934 		(drm_rect_height(&plane_state->uapi.src) >> 16);
935 
936 	return effective_w <= max_w && effective_h <= max_h;
937 }
938 
939 static bool tiling_is_valid(const struct intel_plane_state *plane_state)
940 {
941 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
942 	const struct drm_framebuffer *fb = plane_state->hw.fb;
943 
944 	switch (fb->modifier) {
945 	case DRM_FORMAT_MOD_LINEAR:
946 	case I915_FORMAT_MOD_Y_TILED:
947 	case I915_FORMAT_MOD_Yf_TILED:
948 		return DISPLAY_VER(i915) >= 9;
949 	case I915_FORMAT_MOD_X_TILED:
950 		return true;
951 	default:
952 		return false;
953 	}
954 }
955 
956 static void intel_fbc_update_state(struct intel_atomic_state *state,
957 				   struct intel_crtc *crtc,
958 				   struct intel_plane *plane)
959 {
960 	struct drm_i915_private *i915 = to_i915(state->base.dev);
961 	const struct intel_crtc_state *crtc_state =
962 		intel_atomic_get_new_crtc_state(state, crtc);
963 	const struct intel_plane_state *plane_state =
964 		intel_atomic_get_new_plane_state(state, plane);
965 	struct intel_fbc *fbc = plane->fbc;
966 	struct intel_fbc_state *fbc_state = &fbc->state;
967 
968 	WARN_ON(plane_state->no_fbc_reason);
969 
970 	fbc_state->plane = plane;
971 
972 	/* FBC1 compression interval: arbitrary choice of 1 second */
973 	fbc_state->interval = drm_mode_vrefresh(&crtc_state->hw.adjusted_mode);
974 
975 	fbc_state->fence_y_offset = intel_plane_fence_y_offset(plane_state);
976 
977 	drm_WARN_ON(&i915->drm, plane_state->flags & PLANE_HAS_FENCE &&
978 		    !plane_state->ggtt_vma->fence);
979 
980 	if (plane_state->flags & PLANE_HAS_FENCE &&
981 	    plane_state->ggtt_vma->fence)
982 		fbc_state->fence_id = plane_state->ggtt_vma->fence->id;
983 	else
984 		fbc_state->fence_id = -1;
985 
986 	fbc_state->cfb_stride = intel_fbc_cfb_stride(plane_state);
987 	fbc_state->cfb_size = intel_fbc_cfb_size(plane_state);
988 	fbc_state->override_cfb_stride = intel_fbc_override_cfb_stride(plane_state);
989 }
990 
991 static bool intel_fbc_is_fence_ok(const struct intel_plane_state *plane_state)
992 {
993 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
994 
995 	/* The use of a CPU fence is one of two ways to detect writes by the
996 	 * CPU to the scanout and trigger updates to the FBC.
997 	 *
998 	 * The other method is by software tracking (see
999 	 * intel_fbc_invalidate/flush()), it will manually notify FBC and nuke
1000 	 * the current compressed buffer and recompress it.
1001 	 *
1002 	 * Note that is possible for a tiled surface to be unmappable (and
1003 	 * so have no fence associated with it) due to aperture constraints
1004 	 * at the time of pinning.
1005 	 *
1006 	 * FIXME with 90/270 degree rotation we should use the fence on
1007 	 * the normal GTT view (the rotated view doesn't even have a
1008 	 * fence). Would need changes to the FBC fence Y offset as well.
1009 	 * For now this will effectively disable FBC with 90/270 degree
1010 	 * rotation.
1011 	 */
1012 	return DISPLAY_VER(i915) >= 9 ||
1013 		(plane_state->flags & PLANE_HAS_FENCE &&
1014 		 plane_state->ggtt_vma->fence);
1015 }
1016 
1017 static bool intel_fbc_is_cfb_ok(const struct intel_plane_state *plane_state)
1018 {
1019 	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
1020 	struct intel_fbc *fbc = plane->fbc;
1021 
1022 	return intel_fbc_min_limit(plane_state) <= fbc->limit &&
1023 		intel_fbc_cfb_size(plane_state) <= fbc->compressed_fb.size * fbc->limit;
1024 }
1025 
1026 static bool intel_fbc_is_ok(const struct intel_plane_state *plane_state)
1027 {
1028 	return !plane_state->no_fbc_reason &&
1029 		intel_fbc_is_fence_ok(plane_state) &&
1030 		intel_fbc_is_cfb_ok(plane_state);
1031 }
1032 
1033 static int intel_fbc_check_plane(struct intel_atomic_state *state,
1034 				 struct intel_plane *plane)
1035 {
1036 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1037 	struct intel_plane_state *plane_state =
1038 		intel_atomic_get_new_plane_state(state, plane);
1039 	const struct drm_framebuffer *fb = plane_state->hw.fb;
1040 	struct intel_crtc *crtc = to_intel_crtc(plane_state->uapi.crtc);
1041 	const struct intel_crtc_state *crtc_state;
1042 	struct intel_fbc *fbc = plane->fbc;
1043 
1044 	if (!fbc)
1045 		return 0;
1046 
1047 	if (intel_vgpu_active(i915)) {
1048 		plane_state->no_fbc_reason = "VGPU active";
1049 		return 0;
1050 	}
1051 
1052 	if (!i915->params.enable_fbc) {
1053 		plane_state->no_fbc_reason = "disabled per module param or by default";
1054 		return 0;
1055 	}
1056 
1057 	if (!plane_state->uapi.visible) {
1058 		plane_state->no_fbc_reason = "plane not visible";
1059 		return 0;
1060 	}
1061 
1062 	crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
1063 
1064 	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE) {
1065 		plane_state->no_fbc_reason = "interlaced mode not supported";
1066 		return 0;
1067 	}
1068 
1069 	if (crtc_state->double_wide) {
1070 		plane_state->no_fbc_reason = "double wide pipe not supported";
1071 		return 0;
1072 	}
1073 
1074 	/*
1075 	 * Display 12+ is not supporting FBC with PSR2.
1076 	 * Recommendation is to keep this combination disabled
1077 	 * Bspec: 50422 HSD: 14010260002
1078 	 */
1079 	if (DISPLAY_VER(i915) >= 12 && crtc_state->has_psr2) {
1080 		plane_state->no_fbc_reason = "PSR2 enabled";
1081 		return false;
1082 	}
1083 
1084 	if (!pixel_format_is_valid(plane_state)) {
1085 		plane_state->no_fbc_reason = "pixel format not supported";
1086 		return 0;
1087 	}
1088 
1089 	if (!tiling_is_valid(plane_state)) {
1090 		plane_state->no_fbc_reason = "tiling not supported";
1091 		return 0;
1092 	}
1093 
1094 	if (!rotation_is_valid(plane_state)) {
1095 		plane_state->no_fbc_reason = "rotation not supported";
1096 		return 0;
1097 	}
1098 
1099 	if (!stride_is_valid(plane_state)) {
1100 		plane_state->no_fbc_reason = "stride not supported";
1101 		return 0;
1102 	}
1103 
1104 	if (plane_state->hw.pixel_blend_mode != DRM_MODE_BLEND_PIXEL_NONE &&
1105 	    fb->format->has_alpha) {
1106 		plane_state->no_fbc_reason = "per-pixel alpha not supported";
1107 		return false;
1108 	}
1109 
1110 	if (!intel_fbc_hw_tracking_covers_screen(plane_state)) {
1111 		plane_state->no_fbc_reason = "plane size too big";
1112 		return 0;
1113 	}
1114 
1115 	/*
1116 	 * Work around a problem on GEN9+ HW, where enabling FBC on a plane
1117 	 * having a Y offset that isn't divisible by 4 causes FIFO underrun
1118 	 * and screen flicker.
1119 	 */
1120 	if (DISPLAY_VER(i915) >= 9 &&
1121 	    plane_state->view.color_plane[0].y & 3) {
1122 		plane_state->no_fbc_reason = "plane start Y offset misaligned";
1123 		return false;
1124 	}
1125 
1126 	/* Wa_22010751166: icl, ehl, tgl, dg1, rkl */
1127 	if (DISPLAY_VER(i915) >= 11 &&
1128 	    (plane_state->view.color_plane[0].y +
1129 	     (drm_rect_height(&plane_state->uapi.src) >> 16)) & 3) {
1130 		plane_state->no_fbc_reason = "plane end Y offset misaligned";
1131 		return false;
1132 	}
1133 
1134 	/* WaFbcExceedCdClockThreshold:hsw,bdw */
1135 	if (IS_HASWELL(i915) || IS_BROADWELL(i915)) {
1136 		const struct intel_cdclk_state *cdclk_state;
1137 
1138 		cdclk_state = intel_atomic_get_cdclk_state(state);
1139 		if (IS_ERR(cdclk_state))
1140 			return PTR_ERR(cdclk_state);
1141 
1142 		if (crtc_state->pixel_rate >= cdclk_state->logical.cdclk * 95 / 100) {
1143 			plane_state->no_fbc_reason = "pixel rate too high";
1144 			return 0;
1145 		}
1146 	}
1147 
1148 	plane_state->no_fbc_reason = NULL;
1149 
1150 	return 0;
1151 }
1152 
1153 
1154 static bool intel_fbc_can_flip_nuke(struct intel_atomic_state *state,
1155 				    struct intel_crtc *crtc,
1156 				    struct intel_plane *plane)
1157 {
1158 	const struct intel_crtc_state *new_crtc_state =
1159 		intel_atomic_get_new_crtc_state(state, crtc);
1160 	const struct intel_plane_state *old_plane_state =
1161 		intel_atomic_get_old_plane_state(state, plane);
1162 	const struct intel_plane_state *new_plane_state =
1163 		intel_atomic_get_new_plane_state(state, plane);
1164 	const struct drm_framebuffer *old_fb = old_plane_state->hw.fb;
1165 	const struct drm_framebuffer *new_fb = new_plane_state->hw.fb;
1166 
1167 	if (drm_atomic_crtc_needs_modeset(&new_crtc_state->uapi))
1168 		return false;
1169 
1170 	if (!intel_fbc_is_ok(old_plane_state) ||
1171 	    !intel_fbc_is_ok(new_plane_state))
1172 		return false;
1173 
1174 	if (old_fb->format->format != new_fb->format->format)
1175 		return false;
1176 
1177 	if (old_fb->modifier != new_fb->modifier)
1178 		return false;
1179 
1180 	if (intel_fbc_plane_stride(old_plane_state) !=
1181 	    intel_fbc_plane_stride(new_plane_state))
1182 		return false;
1183 
1184 	if (intel_fbc_cfb_stride(old_plane_state) !=
1185 	    intel_fbc_cfb_stride(new_plane_state))
1186 		return false;
1187 
1188 	if (intel_fbc_cfb_size(old_plane_state) !=
1189 	    intel_fbc_cfb_size(new_plane_state))
1190 		return false;
1191 
1192 	if (intel_fbc_override_cfb_stride(old_plane_state) !=
1193 	    intel_fbc_override_cfb_stride(new_plane_state))
1194 		return false;
1195 
1196 	return true;
1197 }
1198 
1199 static bool __intel_fbc_pre_update(struct intel_atomic_state *state,
1200 				   struct intel_crtc *crtc,
1201 				   struct intel_plane *plane)
1202 {
1203 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1204 	struct intel_fbc *fbc = plane->fbc;
1205 	bool need_vblank_wait = false;
1206 
1207 	fbc->flip_pending = true;
1208 
1209 	if (intel_fbc_can_flip_nuke(state, crtc, plane))
1210 		return need_vblank_wait;
1211 
1212 	intel_fbc_deactivate(fbc, "update pending");
1213 
1214 	/*
1215 	 * Display WA #1198: glk+
1216 	 * Need an extra vblank wait between FBC disable and most plane
1217 	 * updates. Bspec says this is only needed for plane disable, but
1218 	 * that is not true. Touching most plane registers will cause the
1219 	 * corruption to appear. Also SKL/derivatives do not seem to be
1220 	 * affected.
1221 	 *
1222 	 * TODO: could optimize this a bit by sampling the frame
1223 	 * counter when we disable FBC (if it was already done earlier)
1224 	 * and skipping the extra vblank wait before the plane update
1225 	 * if at least one frame has already passed.
1226 	 */
1227 	if (fbc->activated && DISPLAY_VER(i915) >= 10)
1228 		need_vblank_wait = true;
1229 	fbc->activated = false;
1230 
1231 	return need_vblank_wait;
1232 }
1233 
1234 bool intel_fbc_pre_update(struct intel_atomic_state *state,
1235 			  struct intel_crtc *crtc)
1236 {
1237 	const struct intel_plane_state *plane_state;
1238 	bool need_vblank_wait = false;
1239 	struct intel_plane *plane;
1240 	int i;
1241 
1242 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1243 		struct intel_fbc *fbc = plane->fbc;
1244 
1245 		if (!fbc || plane->pipe != crtc->pipe)
1246 			continue;
1247 
1248 		mutex_lock(&fbc->lock);
1249 
1250 		if (fbc->state.plane == plane)
1251 			need_vblank_wait |= __intel_fbc_pre_update(state, crtc, plane);
1252 
1253 		mutex_unlock(&fbc->lock);
1254 	}
1255 
1256 	return need_vblank_wait;
1257 }
1258 
1259 static void __intel_fbc_disable(struct intel_fbc *fbc)
1260 {
1261 	struct drm_i915_private *i915 = fbc->i915;
1262 	struct intel_plane *plane = fbc->state.plane;
1263 
1264 	drm_WARN_ON(&i915->drm, !mutex_is_locked(&fbc->lock));
1265 	drm_WARN_ON(&i915->drm, fbc->active);
1266 
1267 	drm_dbg_kms(&i915->drm, "Disabling FBC on [PLANE:%d:%s]\n",
1268 		    plane->base.base.id, plane->base.name);
1269 
1270 	__intel_fbc_cleanup_cfb(fbc);
1271 
1272 	fbc->state.plane = NULL;
1273 }
1274 
1275 static void __intel_fbc_post_update(struct intel_fbc *fbc)
1276 {
1277 	struct drm_i915_private *i915 = fbc->i915;
1278 
1279 	drm_WARN_ON(&i915->drm, !mutex_is_locked(&fbc->lock));
1280 
1281 	if (!fbc->busy_bits)
1282 		intel_fbc_activate(fbc);
1283 	else
1284 		intel_fbc_deactivate(fbc, "frontbuffer write");
1285 }
1286 
1287 void intel_fbc_post_update(struct intel_atomic_state *state,
1288 			   struct intel_crtc *crtc)
1289 {
1290 	const struct intel_plane_state *plane_state;
1291 	struct intel_plane *plane;
1292 	int i;
1293 
1294 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1295 		struct intel_fbc *fbc = plane->fbc;
1296 
1297 		if (!fbc || plane->pipe != crtc->pipe)
1298 			continue;
1299 
1300 		mutex_lock(&fbc->lock);
1301 
1302 		if (fbc->state.plane == plane) {
1303 			fbc->flip_pending = false;
1304 			__intel_fbc_post_update(fbc);
1305 		}
1306 
1307 		mutex_unlock(&fbc->lock);
1308 	}
1309 }
1310 
1311 static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
1312 {
1313 	if (fbc->state.plane)
1314 		return fbc->state.plane->frontbuffer_bit;
1315 	else
1316 		return fbc->possible_framebuffer_bits;
1317 }
1318 
1319 static void __intel_fbc_invalidate(struct intel_fbc *fbc,
1320 				   unsigned int frontbuffer_bits,
1321 				   enum fb_op_origin origin)
1322 {
1323 	if (origin == ORIGIN_FLIP || origin == ORIGIN_CURSOR_UPDATE)
1324 		return;
1325 
1326 	mutex_lock(&fbc->lock);
1327 
1328 	fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
1329 
1330 	if (fbc->state.plane && fbc->busy_bits)
1331 		intel_fbc_deactivate(fbc, "frontbuffer write");
1332 
1333 	mutex_unlock(&fbc->lock);
1334 }
1335 
1336 void intel_fbc_invalidate(struct drm_i915_private *i915,
1337 			  unsigned int frontbuffer_bits,
1338 			  enum fb_op_origin origin)
1339 {
1340 	struct intel_fbc *fbc;
1341 	enum intel_fbc_id fbc_id;
1342 
1343 	for_each_intel_fbc(i915, fbc, fbc_id)
1344 		__intel_fbc_invalidate(fbc, frontbuffer_bits, origin);
1345 
1346 }
1347 
1348 static void __intel_fbc_flush(struct intel_fbc *fbc,
1349 			      unsigned int frontbuffer_bits,
1350 			      enum fb_op_origin origin)
1351 {
1352 	mutex_lock(&fbc->lock);
1353 
1354 	fbc->busy_bits &= ~frontbuffer_bits;
1355 
1356 	if (origin == ORIGIN_FLIP || origin == ORIGIN_CURSOR_UPDATE)
1357 		goto out;
1358 
1359 	if (!fbc->busy_bits && fbc->state.plane &&
1360 	    (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
1361 		if (fbc->active)
1362 			intel_fbc_nuke(fbc);
1363 		else if (!fbc->flip_pending)
1364 			__intel_fbc_post_update(fbc);
1365 	}
1366 
1367 out:
1368 	mutex_unlock(&fbc->lock);
1369 }
1370 
1371 void intel_fbc_flush(struct drm_i915_private *i915,
1372 		     unsigned int frontbuffer_bits,
1373 		     enum fb_op_origin origin)
1374 {
1375 	struct intel_fbc *fbc;
1376 	enum intel_fbc_id fbc_id;
1377 
1378 	for_each_intel_fbc(i915, fbc, fbc_id)
1379 		__intel_fbc_flush(fbc, frontbuffer_bits, origin);
1380 }
1381 
1382 int intel_fbc_atomic_check(struct intel_atomic_state *state)
1383 {
1384 	struct intel_plane_state *plane_state;
1385 	struct intel_plane *plane;
1386 	int i;
1387 
1388 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1389 		int ret;
1390 
1391 		ret = intel_fbc_check_plane(state, plane);
1392 		if (ret)
1393 			return ret;
1394 	}
1395 
1396 	return 0;
1397 }
1398 
1399 static void __intel_fbc_enable(struct intel_atomic_state *state,
1400 			       struct intel_crtc *crtc,
1401 			       struct intel_plane *plane)
1402 {
1403 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1404 	const struct intel_plane_state *plane_state =
1405 		intel_atomic_get_new_plane_state(state, plane);
1406 	struct intel_fbc *fbc = plane->fbc;
1407 
1408 	if (fbc->state.plane) {
1409 		if (fbc->state.plane != plane)
1410 			return;
1411 
1412 		if (intel_fbc_is_ok(plane_state)) {
1413 			intel_fbc_update_state(state, crtc, plane);
1414 			return;
1415 		}
1416 
1417 		__intel_fbc_disable(fbc);
1418 	}
1419 
1420 	drm_WARN_ON(&i915->drm, fbc->active);
1421 
1422 	fbc->no_fbc_reason = plane_state->no_fbc_reason;
1423 	if (fbc->no_fbc_reason)
1424 		return;
1425 
1426 	if (!intel_fbc_is_fence_ok(plane_state)) {
1427 		fbc->no_fbc_reason = "framebuffer not fenced";
1428 		return;
1429 	}
1430 
1431 	if (fbc->underrun_detected) {
1432 		fbc->no_fbc_reason = "FIFO underrun";
1433 		return;
1434 	}
1435 
1436 	if (intel_fbc_alloc_cfb(fbc, intel_fbc_cfb_size(plane_state),
1437 				intel_fbc_min_limit(plane_state))) {
1438 		fbc->no_fbc_reason = "not enough stolen memory";
1439 		return;
1440 	}
1441 
1442 	drm_dbg_kms(&i915->drm, "Enabling FBC on [PLANE:%d:%s]\n",
1443 		    plane->base.base.id, plane->base.name);
1444 	fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1445 
1446 	intel_fbc_update_state(state, crtc, plane);
1447 
1448 	intel_fbc_program_cfb(fbc);
1449 }
1450 
1451 /**
1452  * intel_fbc_disable - disable FBC if it's associated with crtc
1453  * @crtc: the CRTC
1454  *
1455  * This function disables FBC if it's associated with the provided CRTC.
1456  */
1457 void intel_fbc_disable(struct intel_crtc *crtc)
1458 {
1459 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
1460 	struct intel_plane *plane;
1461 
1462 	for_each_intel_plane(&i915->drm, plane) {
1463 		struct intel_fbc *fbc = plane->fbc;
1464 
1465 		if (!fbc || plane->pipe != crtc->pipe)
1466 			continue;
1467 
1468 		mutex_lock(&fbc->lock);
1469 		if (fbc->state.plane == plane)
1470 			__intel_fbc_disable(fbc);
1471 		mutex_unlock(&fbc->lock);
1472 	}
1473 }
1474 
1475 void intel_fbc_update(struct intel_atomic_state *state,
1476 		      struct intel_crtc *crtc)
1477 {
1478 	const struct intel_crtc_state *crtc_state =
1479 		intel_atomic_get_new_crtc_state(state, crtc);
1480 	const struct intel_plane_state *plane_state;
1481 	struct intel_plane *plane;
1482 	int i;
1483 
1484 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1485 		struct intel_fbc *fbc = plane->fbc;
1486 
1487 		if (!fbc || plane->pipe != crtc->pipe)
1488 			continue;
1489 
1490 		mutex_lock(&fbc->lock);
1491 
1492 		if (crtc_state->update_pipe && plane_state->no_fbc_reason) {
1493 			if (fbc->state.plane == plane)
1494 				__intel_fbc_disable(fbc);
1495 		} else {
1496 			__intel_fbc_enable(state, crtc, plane);
1497 		}
1498 
1499 		mutex_unlock(&fbc->lock);
1500 	}
1501 }
1502 
1503 /**
1504  * intel_fbc_global_disable - globally disable FBC
1505  * @i915: i915 device instance
1506  *
1507  * This function disables FBC regardless of which CRTC is associated with it.
1508  */
1509 void intel_fbc_global_disable(struct drm_i915_private *i915)
1510 {
1511 	struct intel_fbc *fbc;
1512 	enum intel_fbc_id fbc_id;
1513 
1514 	for_each_intel_fbc(i915, fbc, fbc_id) {
1515 		mutex_lock(&fbc->lock);
1516 		if (fbc->state.plane)
1517 			__intel_fbc_disable(fbc);
1518 		mutex_unlock(&fbc->lock);
1519 	}
1520 }
1521 
1522 static void intel_fbc_underrun_work_fn(struct work_struct *work)
1523 {
1524 	struct intel_fbc *fbc = container_of(work, typeof(*fbc), underrun_work);
1525 	struct drm_i915_private *i915 = fbc->i915;
1526 
1527 	mutex_lock(&fbc->lock);
1528 
1529 	/* Maybe we were scheduled twice. */
1530 	if (fbc->underrun_detected || !fbc->state.plane)
1531 		goto out;
1532 
1533 	drm_dbg_kms(&i915->drm, "Disabling FBC due to FIFO underrun.\n");
1534 	fbc->underrun_detected = true;
1535 
1536 	intel_fbc_deactivate(fbc, "FIFO underrun");
1537 	if (!fbc->flip_pending)
1538 		intel_crtc_wait_for_next_vblank(intel_crtc_for_pipe(i915, fbc->state.plane->pipe));
1539 	__intel_fbc_disable(fbc);
1540 out:
1541 	mutex_unlock(&fbc->lock);
1542 }
1543 
1544 static void __intel_fbc_reset_underrun(struct intel_fbc *fbc)
1545 {
1546 	struct drm_i915_private *i915 = fbc->i915;
1547 
1548 	cancel_work_sync(&fbc->underrun_work);
1549 
1550 	mutex_lock(&fbc->lock);
1551 
1552 	if (fbc->underrun_detected) {
1553 		drm_dbg_kms(&i915->drm,
1554 			    "Re-allowing FBC after fifo underrun\n");
1555 		fbc->no_fbc_reason = "FIFO underrun cleared";
1556 	}
1557 
1558 	fbc->underrun_detected = false;
1559 	mutex_unlock(&fbc->lock);
1560 }
1561 
1562 /*
1563  * intel_fbc_reset_underrun - reset FBC fifo underrun status.
1564  * @i915: the i915 device
1565  *
1566  * See intel_fbc_handle_fifo_underrun_irq(). For automated testing we
1567  * want to re-enable FBC after an underrun to increase test coverage.
1568  */
1569 void intel_fbc_reset_underrun(struct drm_i915_private *i915)
1570 {
1571 	struct intel_fbc *fbc;
1572 	enum intel_fbc_id fbc_id;
1573 
1574 	for_each_intel_fbc(i915, fbc, fbc_id)
1575 		__intel_fbc_reset_underrun(fbc);
1576 }
1577 
1578 static void __intel_fbc_handle_fifo_underrun_irq(struct intel_fbc *fbc)
1579 {
1580 	/*
1581 	 * There's no guarantee that underrun_detected won't be set to true
1582 	 * right after this check and before the work is scheduled, but that's
1583 	 * not a problem since we'll check it again under the work function
1584 	 * while FBC is locked. This check here is just to prevent us from
1585 	 * unnecessarily scheduling the work, and it relies on the fact that we
1586 	 * never switch underrun_detect back to false after it's true.
1587 	 */
1588 	if (READ_ONCE(fbc->underrun_detected))
1589 		return;
1590 
1591 	schedule_work(&fbc->underrun_work);
1592 }
1593 
1594 /**
1595  * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
1596  * @i915: i915 device
1597  *
1598  * Without FBC, most underruns are harmless and don't really cause too many
1599  * problems, except for an annoying message on dmesg. With FBC, underruns can
1600  * become black screens or even worse, especially when paired with bad
1601  * watermarks. So in order for us to be on the safe side, completely disable FBC
1602  * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
1603  * already suggests that watermarks may be bad, so try to be as safe as
1604  * possible.
1605  *
1606  * This function is called from the IRQ handler.
1607  */
1608 void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *i915)
1609 {
1610 	struct intel_fbc *fbc;
1611 	enum intel_fbc_id fbc_id;
1612 
1613 	for_each_intel_fbc(i915, fbc, fbc_id)
1614 		__intel_fbc_handle_fifo_underrun_irq(fbc);
1615 }
1616 
1617 /*
1618  * The DDX driver changes its behavior depending on the value it reads from
1619  * i915.enable_fbc, so sanitize it by translating the default value into either
1620  * 0 or 1 in order to allow it to know what's going on.
1621  *
1622  * Notice that this is done at driver initialization and we still allow user
1623  * space to change the value during runtime without sanitizing it again. IGT
1624  * relies on being able to change i915.enable_fbc at runtime.
1625  */
1626 static int intel_sanitize_fbc_option(struct drm_i915_private *i915)
1627 {
1628 	if (i915->params.enable_fbc >= 0)
1629 		return !!i915->params.enable_fbc;
1630 
1631 	if (!HAS_FBC(i915))
1632 		return 0;
1633 
1634 	if (IS_BROADWELL(i915) || DISPLAY_VER(i915) >= 9)
1635 		return 1;
1636 
1637 	return 0;
1638 }
1639 
1640 static bool need_fbc_vtd_wa(struct drm_i915_private *i915)
1641 {
1642 	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
1643 	if (intel_vtd_active(i915) &&
1644 	    (IS_SKYLAKE(i915) || IS_BROXTON(i915))) {
1645 		drm_info(&i915->drm,
1646 			 "Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
1647 		return true;
1648 	}
1649 
1650 	return false;
1651 }
1652 
1653 void intel_fbc_add_plane(struct intel_fbc *fbc, struct intel_plane *plane)
1654 {
1655 	if (!fbc)
1656 		return;
1657 
1658 	plane->fbc = fbc;
1659 	fbc->possible_framebuffer_bits |= plane->frontbuffer_bit;
1660 }
1661 
1662 static struct intel_fbc *intel_fbc_create(struct drm_i915_private *i915,
1663 					  enum intel_fbc_id fbc_id)
1664 {
1665 	struct intel_fbc *fbc;
1666 
1667 	fbc = kzalloc(sizeof(*fbc), GFP_KERNEL);
1668 	if (!fbc)
1669 		return NULL;
1670 
1671 	fbc->id = fbc_id;
1672 	fbc->i915 = i915;
1673 	INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
1674 	mutex_init(&fbc->lock);
1675 
1676 	if (DISPLAY_VER(i915) >= 7)
1677 		fbc->funcs = &ivb_fbc_funcs;
1678 	else if (DISPLAY_VER(i915) == 6)
1679 		fbc->funcs = &snb_fbc_funcs;
1680 	else if (DISPLAY_VER(i915) == 5)
1681 		fbc->funcs = &ilk_fbc_funcs;
1682 	else if (IS_G4X(i915))
1683 		fbc->funcs = &g4x_fbc_funcs;
1684 	else if (DISPLAY_VER(i915) == 4)
1685 		fbc->funcs = &i965_fbc_funcs;
1686 	else
1687 		fbc->funcs = &i8xx_fbc_funcs;
1688 
1689 	return fbc;
1690 }
1691 
1692 /**
1693  * intel_fbc_init - Initialize FBC
1694  * @i915: the i915 device
1695  *
1696  * This function might be called during PM init process.
1697  */
1698 void intel_fbc_init(struct drm_i915_private *i915)
1699 {
1700 	enum intel_fbc_id fbc_id;
1701 
1702 	if (!drm_mm_initialized(&i915->mm.stolen))
1703 		mkwrite_device_info(i915)->display.fbc_mask = 0;
1704 
1705 	if (need_fbc_vtd_wa(i915))
1706 		mkwrite_device_info(i915)->display.fbc_mask = 0;
1707 
1708 	i915->params.enable_fbc = intel_sanitize_fbc_option(i915);
1709 	drm_dbg_kms(&i915->drm, "Sanitized enable_fbc value: %d\n",
1710 		    i915->params.enable_fbc);
1711 
1712 	for_each_fbc_id(i915, fbc_id) {
1713 		struct intel_fbc *fbc;
1714 
1715 		fbc = intel_fbc_create(i915, fbc_id);
1716 		if (!fbc)
1717 			continue;
1718 
1719 		/*
1720 		 * We still don't have any sort of hardware state readout
1721 		 * for FBC, so deactivate it in case the BIOS activated it
1722 		 * to make sure software matches the hardware state.
1723 		 */
1724 		if (intel_fbc_hw_is_active(fbc))
1725 			intel_fbc_hw_deactivate(fbc);
1726 
1727 		i915->fbc[fbc->id] = fbc;
1728 	}
1729 }
1730 
1731 static int intel_fbc_debugfs_status_show(struct seq_file *m, void *unused)
1732 {
1733 	struct intel_fbc *fbc = m->private;
1734 	struct drm_i915_private *i915 = fbc->i915;
1735 	struct intel_plane *plane;
1736 	intel_wakeref_t wakeref;
1737 
1738 	drm_modeset_lock_all(&i915->drm);
1739 
1740 	wakeref = intel_runtime_pm_get(&i915->runtime_pm);
1741 	mutex_lock(&fbc->lock);
1742 
1743 	if (fbc->active) {
1744 		seq_puts(m, "FBC enabled\n");
1745 		seq_printf(m, "Compressing: %s\n",
1746 			   yesno(intel_fbc_is_compressing(fbc)));
1747 	} else {
1748 		seq_printf(m, "FBC disabled: %s\n", fbc->no_fbc_reason);
1749 	}
1750 
1751 	for_each_intel_plane(&i915->drm, plane) {
1752 		const struct intel_plane_state *plane_state =
1753 			to_intel_plane_state(plane->base.state);
1754 
1755 		if (plane->fbc != fbc)
1756 			continue;
1757 
1758 		seq_printf(m, "%c [PLANE:%d:%s]: %s\n",
1759 			   fbc->state.plane == plane ? '*' : ' ',
1760 			   plane->base.base.id, plane->base.name,
1761 			   plane_state->no_fbc_reason ?: "FBC possible");
1762 	}
1763 
1764 	mutex_unlock(&fbc->lock);
1765 	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
1766 
1767 	drm_modeset_unlock_all(&i915->drm);
1768 
1769 	return 0;
1770 }
1771 
1772 DEFINE_SHOW_ATTRIBUTE(intel_fbc_debugfs_status);
1773 
1774 static int intel_fbc_debugfs_false_color_get(void *data, u64 *val)
1775 {
1776 	struct intel_fbc *fbc = data;
1777 
1778 	*val = fbc->false_color;
1779 
1780 	return 0;
1781 }
1782 
1783 static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
1784 {
1785 	struct intel_fbc *fbc = data;
1786 
1787 	mutex_lock(&fbc->lock);
1788 
1789 	fbc->false_color = val;
1790 
1791 	if (fbc->active)
1792 		fbc->funcs->set_false_color(fbc, fbc->false_color);
1793 
1794 	mutex_unlock(&fbc->lock);
1795 
1796 	return 0;
1797 }
1798 
1799 DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
1800 			intel_fbc_debugfs_false_color_get,
1801 			intel_fbc_debugfs_false_color_set,
1802 			"%llu\n");
1803 
1804 static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
1805 				  struct dentry *parent)
1806 {
1807 	debugfs_create_file("i915_fbc_status", 0444, parent,
1808 			    fbc, &intel_fbc_debugfs_status_fops);
1809 
1810 	if (fbc->funcs->set_false_color)
1811 		debugfs_create_file("i915_fbc_false_color", 0644, parent,
1812 				    fbc, &intel_fbc_debugfs_false_color_fops);
1813 }
1814 
1815 void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
1816 {
1817 	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1818 
1819 	if (plane->fbc)
1820 		intel_fbc_debugfs_add(plane->fbc, crtc->base.debugfs_entry);
1821 }
1822 
1823 /* FIXME: remove this once igt is on board with per-crtc stuff */
1824 void intel_fbc_debugfs_register(struct drm_i915_private *i915)
1825 {
1826 	struct drm_minor *minor = i915->drm.primary;
1827 	struct intel_fbc *fbc;
1828 
1829 	fbc = i915->fbc[INTEL_FBC_A];
1830 	if (fbc)
1831 		intel_fbc_debugfs_add(fbc, minor->debugfs_root);
1832 }
1833