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