xref: /linux/drivers/gpu/drm/i915/display/intel_fbc.c (revision cad151904379b302a62e8967b7db6ba2e883a212)
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 <linux/string_helpers.h>
42 
43 #include <drm/drm_blend.h>
44 #include <drm/drm_fourcc.h>
45 
46 #include "i915_drv.h"
47 #include "i915_reg.h"
48 #include "i915_utils.h"
49 #include "i915_vgpu.h"
50 #include "i915_vma.h"
51 #include "intel_cdclk.h"
52 #include "intel_de.h"
53 #include "intel_display_device.h"
54 #include "intel_display_trace.h"
55 #include "intel_display_types.h"
56 #include "intel_fbc.h"
57 #include "intel_frontbuffer.h"
58 
59 #define for_each_fbc_id(__dev_priv, __fbc_id) \
60 	for ((__fbc_id) = INTEL_FBC_A; (__fbc_id) < I915_MAX_FBCS; (__fbc_id)++) \
61 		for_each_if(DISPLAY_RUNTIME_INFO(__dev_priv)->fbc_mask & BIT(__fbc_id))
62 
63 #define for_each_intel_fbc(__dev_priv, __fbc, __fbc_id) \
64 	for_each_fbc_id((__dev_priv), (__fbc_id)) \
65 		for_each_if((__fbc) = (__dev_priv)->display.fbc[(__fbc_id)])
66 
67 struct intel_fbc_funcs {
68 	void (*activate)(struct intel_fbc *fbc);
69 	void (*deactivate)(struct intel_fbc *fbc);
70 	bool (*is_active)(struct intel_fbc *fbc);
71 	bool (*is_compressing)(struct intel_fbc *fbc);
72 	void (*nuke)(struct intel_fbc *fbc);
73 	void (*program_cfb)(struct intel_fbc *fbc);
74 	void (*set_false_color)(struct intel_fbc *fbc, bool enable);
75 };
76 
77 struct intel_fbc_state {
78 	struct intel_plane *plane;
79 	unsigned int cfb_stride;
80 	unsigned int cfb_size;
81 	unsigned int fence_y_offset;
82 	u16 override_cfb_stride;
83 	u16 interval;
84 	s8 fence_id;
85 };
86 
87 struct intel_fbc {
88 	struct drm_i915_private *i915;
89 	const struct intel_fbc_funcs *funcs;
90 
91 	/*
92 	 * This is always the inner lock when overlapping with
93 	 * struct_mutex and it's the outer lock when overlapping
94 	 * with stolen_lock.
95 	 */
96 	struct mutex lock;
97 	unsigned int busy_bits;
98 
99 	struct i915_stolen_fb compressed_fb, compressed_llb;
100 
101 	enum intel_fbc_id id;
102 
103 	u8 limit;
104 
105 	bool false_color;
106 
107 	bool active;
108 	bool activated;
109 	bool flip_pending;
110 
111 	bool underrun_detected;
112 	struct work_struct underrun_work;
113 
114 	/*
115 	 * This structure contains everything that's relevant to program the
116 	 * hardware registers. When we want to figure out if we need to disable
117 	 * and re-enable FBC for a new configuration we just check if there's
118 	 * something different in the struct. The genx_fbc_activate functions
119 	 * are supposed to read from it in order to program the registers.
120 	 */
121 	struct intel_fbc_state state;
122 	const char *no_fbc_reason;
123 };
124 
125 /* plane stride in pixels */
126 static unsigned int intel_fbc_plane_stride(const struct intel_plane_state *plane_state)
127 {
128 	const struct drm_framebuffer *fb = plane_state->hw.fb;
129 	unsigned int stride;
130 
131 	stride = plane_state->view.color_plane[0].mapping_stride;
132 	if (!drm_rotation_90_or_270(plane_state->hw.rotation))
133 		stride /= fb->format->cpp[0];
134 
135 	return stride;
136 }
137 
138 /* plane stride based cfb stride in bytes, assuming 1:1 compression limit */
139 static unsigned int _intel_fbc_cfb_stride(const struct intel_plane_state *plane_state)
140 {
141 	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
142 
143 	return intel_fbc_plane_stride(plane_state) * cpp;
144 }
145 
146 /* minimum acceptable cfb stride in bytes, assuming 1:1 compression limit */
147 static unsigned int skl_fbc_min_cfb_stride(const struct intel_plane_state *plane_state)
148 {
149 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
150 	unsigned int limit = 4; /* 1:4 compression limit is the worst case */
151 	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
152 	unsigned int width = drm_rect_width(&plane_state->uapi.src) >> 16;
153 	unsigned int height = 4; /* FBC segment is 4 lines */
154 	unsigned int stride;
155 
156 	/* minimum segment stride we can use */
157 	stride = width * cpp * height / limit;
158 
159 	/*
160 	 * Wa_16011863758: icl+
161 	 * Avoid some hardware segment address miscalculation.
162 	 */
163 	if (DISPLAY_VER(i915) >= 11)
164 		stride += 64;
165 
166 	/*
167 	 * At least some of the platforms require each 4 line segment to
168 	 * be 512 byte aligned. Just do it always for simplicity.
169 	 */
170 	stride = ALIGN(stride, 512);
171 
172 	/* convert back to single line equivalent with 1:1 compression limit */
173 	return stride * limit / height;
174 }
175 
176 /* properly aligned cfb stride in bytes, assuming 1:1 compression limit */
177 static unsigned int intel_fbc_cfb_stride(const struct intel_plane_state *plane_state)
178 {
179 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
180 	unsigned int stride = _intel_fbc_cfb_stride(plane_state);
181 
182 	/*
183 	 * At least some of the platforms require each 4 line segment to
184 	 * be 512 byte aligned. Aligning each line to 512 bytes guarantees
185 	 * that regardless of the compression limit we choose later.
186 	 */
187 	if (DISPLAY_VER(i915) >= 9)
188 		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(plane_state));
189 	else
190 		return stride;
191 }
192 
193 static unsigned int intel_fbc_cfb_size(const struct intel_plane_state *plane_state)
194 {
195 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
196 	int lines = drm_rect_height(&plane_state->uapi.src) >> 16;
197 
198 	if (DISPLAY_VER(i915) == 7)
199 		lines = min(lines, 2048);
200 	else if (DISPLAY_VER(i915) >= 8)
201 		lines = min(lines, 2560);
202 
203 	return lines * intel_fbc_cfb_stride(plane_state);
204 }
205 
206 static u16 intel_fbc_override_cfb_stride(const struct intel_plane_state *plane_state)
207 {
208 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
209 	unsigned int stride_aligned = intel_fbc_cfb_stride(plane_state);
210 	unsigned int stride = _intel_fbc_cfb_stride(plane_state);
211 	const struct drm_framebuffer *fb = plane_state->hw.fb;
212 
213 	/*
214 	 * Override stride in 64 byte units per 4 line segment.
215 	 *
216 	 * Gen9 hw miscalculates cfb stride for linear as
217 	 * PLANE_STRIDE*512 instead of PLANE_STRIDE*64, so
218 	 * we always need to use the override there.
219 	 */
220 	if (stride != stride_aligned ||
221 	    (DISPLAY_VER(i915) == 9 && fb->modifier == DRM_FORMAT_MOD_LINEAR))
222 		return stride_aligned * 4 / 64;
223 
224 	return 0;
225 }
226 
227 static u32 i8xx_fbc_ctl(struct intel_fbc *fbc)
228 {
229 	const struct intel_fbc_state *fbc_state = &fbc->state;
230 	struct drm_i915_private *i915 = fbc->i915;
231 	unsigned int cfb_stride;
232 	u32 fbc_ctl;
233 
234 	cfb_stride = fbc_state->cfb_stride / fbc->limit;
235 
236 	/* FBC_CTL wants 32B or 64B units */
237 	if (DISPLAY_VER(i915) == 2)
238 		cfb_stride = (cfb_stride / 32) - 1;
239 	else
240 		cfb_stride = (cfb_stride / 64) - 1;
241 
242 	fbc_ctl = FBC_CTL_PERIODIC |
243 		FBC_CTL_INTERVAL(fbc_state->interval) |
244 		FBC_CTL_STRIDE(cfb_stride);
245 
246 	if (IS_I945GM(i915))
247 		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
248 
249 	if (fbc_state->fence_id >= 0)
250 		fbc_ctl |= FBC_CTL_FENCENO(fbc_state->fence_id);
251 
252 	return fbc_ctl;
253 }
254 
255 static u32 i965_fbc_ctl2(struct intel_fbc *fbc)
256 {
257 	const struct intel_fbc_state *fbc_state = &fbc->state;
258 	u32 fbc_ctl2;
259 
260 	fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM |
261 		FBC_CTL_PLANE(fbc_state->plane->i9xx_plane);
262 
263 	if (fbc_state->fence_id >= 0)
264 		fbc_ctl2 |= FBC_CTL_CPU_FENCE_EN;
265 
266 	return fbc_ctl2;
267 }
268 
269 static void i8xx_fbc_deactivate(struct intel_fbc *fbc)
270 {
271 	struct drm_i915_private *i915 = fbc->i915;
272 	u32 fbc_ctl;
273 
274 	/* Disable compression */
275 	fbc_ctl = intel_de_read(i915, FBC_CONTROL);
276 	if ((fbc_ctl & FBC_CTL_EN) == 0)
277 		return;
278 
279 	fbc_ctl &= ~FBC_CTL_EN;
280 	intel_de_write(i915, FBC_CONTROL, fbc_ctl);
281 
282 	/* Wait for compressing bit to clear */
283 	if (intel_de_wait_for_clear(i915, FBC_STATUS,
284 				    FBC_STAT_COMPRESSING, 10)) {
285 		drm_dbg_kms(&i915->drm, "FBC idle timed out\n");
286 		return;
287 	}
288 }
289 
290 static void i8xx_fbc_activate(struct intel_fbc *fbc)
291 {
292 	const struct intel_fbc_state *fbc_state = &fbc->state;
293 	struct drm_i915_private *i915 = fbc->i915;
294 	int i;
295 
296 	/* Clear old tags */
297 	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
298 		intel_de_write(i915, FBC_TAG(i), 0);
299 
300 	if (DISPLAY_VER(i915) == 4) {
301 		intel_de_write(i915, FBC_CONTROL2,
302 			       i965_fbc_ctl2(fbc));
303 		intel_de_write(i915, FBC_FENCE_OFF,
304 			       fbc_state->fence_y_offset);
305 	}
306 
307 	intel_de_write(i915, FBC_CONTROL,
308 		       FBC_CTL_EN | i8xx_fbc_ctl(fbc));
309 }
310 
311 static bool i8xx_fbc_is_active(struct intel_fbc *fbc)
312 {
313 	return intel_de_read(fbc->i915, FBC_CONTROL) & FBC_CTL_EN;
314 }
315 
316 static bool i8xx_fbc_is_compressing(struct intel_fbc *fbc)
317 {
318 	return intel_de_read(fbc->i915, FBC_STATUS) &
319 		(FBC_STAT_COMPRESSING | FBC_STAT_COMPRESSED);
320 }
321 
322 static void i8xx_fbc_nuke(struct intel_fbc *fbc)
323 {
324 	struct intel_fbc_state *fbc_state = &fbc->state;
325 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
326 	struct drm_i915_private *dev_priv = fbc->i915;
327 
328 	intel_de_write_fw(dev_priv, DSPADDR(i9xx_plane),
329 			  intel_de_read_fw(dev_priv, DSPADDR(i9xx_plane)));
330 }
331 
332 static void i8xx_fbc_program_cfb(struct intel_fbc *fbc)
333 {
334 	struct drm_i915_private *i915 = fbc->i915;
335 
336 	drm_WARN_ON(&i915->drm,
337 		    range_overflows_end_t(u64, i915_gem_stolen_area_address(i915),
338 					  i915_gem_stolen_node_offset(&fbc->compressed_fb),
339 					  U32_MAX));
340 	drm_WARN_ON(&i915->drm,
341 		    range_overflows_end_t(u64, i915_gem_stolen_area_address(i915),
342 					  i915_gem_stolen_node_offset(&fbc->compressed_llb),
343 					  U32_MAX));
344 	intel_de_write(i915, FBC_CFB_BASE,
345 		       i915_gem_stolen_node_address(i915, &fbc->compressed_fb));
346 	intel_de_write(i915, FBC_LL_BASE,
347 		       i915_gem_stolen_node_address(i915, &fbc->compressed_llb));
348 }
349 
350 static const struct intel_fbc_funcs i8xx_fbc_funcs = {
351 	.activate = i8xx_fbc_activate,
352 	.deactivate = i8xx_fbc_deactivate,
353 	.is_active = i8xx_fbc_is_active,
354 	.is_compressing = i8xx_fbc_is_compressing,
355 	.nuke = i8xx_fbc_nuke,
356 	.program_cfb = i8xx_fbc_program_cfb,
357 };
358 
359 static void i965_fbc_nuke(struct intel_fbc *fbc)
360 {
361 	struct intel_fbc_state *fbc_state = &fbc->state;
362 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
363 	struct drm_i915_private *dev_priv = fbc->i915;
364 
365 	intel_de_write_fw(dev_priv, DSPSURF(i9xx_plane),
366 			  intel_de_read_fw(dev_priv, DSPSURF(i9xx_plane)));
367 }
368 
369 static const struct intel_fbc_funcs i965_fbc_funcs = {
370 	.activate = i8xx_fbc_activate,
371 	.deactivate = i8xx_fbc_deactivate,
372 	.is_active = i8xx_fbc_is_active,
373 	.is_compressing = i8xx_fbc_is_compressing,
374 	.nuke = i965_fbc_nuke,
375 	.program_cfb = i8xx_fbc_program_cfb,
376 };
377 
378 static u32 g4x_dpfc_ctl_limit(struct intel_fbc *fbc)
379 {
380 	switch (fbc->limit) {
381 	default:
382 		MISSING_CASE(fbc->limit);
383 		fallthrough;
384 	case 1:
385 		return DPFC_CTL_LIMIT_1X;
386 	case 2:
387 		return DPFC_CTL_LIMIT_2X;
388 	case 4:
389 		return DPFC_CTL_LIMIT_4X;
390 	}
391 }
392 
393 static u32 g4x_dpfc_ctl(struct intel_fbc *fbc)
394 {
395 	const struct intel_fbc_state *fbc_state = &fbc->state;
396 	struct drm_i915_private *i915 = fbc->i915;
397 	u32 dpfc_ctl;
398 
399 	dpfc_ctl = g4x_dpfc_ctl_limit(fbc) |
400 		DPFC_CTL_PLANE_G4X(fbc_state->plane->i9xx_plane);
401 
402 	if (IS_G4X(i915))
403 		dpfc_ctl |= DPFC_CTL_SR_EN;
404 
405 	if (fbc_state->fence_id >= 0) {
406 		dpfc_ctl |= DPFC_CTL_FENCE_EN_G4X;
407 
408 		if (DISPLAY_VER(i915) < 6)
409 			dpfc_ctl |= DPFC_CTL_FENCENO(fbc_state->fence_id);
410 	}
411 
412 	return dpfc_ctl;
413 }
414 
415 static void g4x_fbc_activate(struct intel_fbc *fbc)
416 {
417 	const struct intel_fbc_state *fbc_state = &fbc->state;
418 	struct drm_i915_private *i915 = fbc->i915;
419 
420 	intel_de_write(i915, DPFC_FENCE_YOFF,
421 		       fbc_state->fence_y_offset);
422 
423 	intel_de_write(i915, DPFC_CONTROL,
424 		       DPFC_CTL_EN | g4x_dpfc_ctl(fbc));
425 }
426 
427 static void g4x_fbc_deactivate(struct intel_fbc *fbc)
428 {
429 	struct drm_i915_private *i915 = fbc->i915;
430 	u32 dpfc_ctl;
431 
432 	/* Disable compression */
433 	dpfc_ctl = intel_de_read(i915, DPFC_CONTROL);
434 	if (dpfc_ctl & DPFC_CTL_EN) {
435 		dpfc_ctl &= ~DPFC_CTL_EN;
436 		intel_de_write(i915, DPFC_CONTROL, dpfc_ctl);
437 	}
438 }
439 
440 static bool g4x_fbc_is_active(struct intel_fbc *fbc)
441 {
442 	return intel_de_read(fbc->i915, DPFC_CONTROL) & DPFC_CTL_EN;
443 }
444 
445 static bool g4x_fbc_is_compressing(struct intel_fbc *fbc)
446 {
447 	return intel_de_read(fbc->i915, DPFC_STATUS) & DPFC_COMP_SEG_MASK;
448 }
449 
450 static void g4x_fbc_program_cfb(struct intel_fbc *fbc)
451 {
452 	struct drm_i915_private *i915 = fbc->i915;
453 
454 	intel_de_write(i915, DPFC_CB_BASE,
455 		       i915_gem_stolen_node_offset(&fbc->compressed_fb));
456 }
457 
458 static const struct intel_fbc_funcs g4x_fbc_funcs = {
459 	.activate = g4x_fbc_activate,
460 	.deactivate = g4x_fbc_deactivate,
461 	.is_active = g4x_fbc_is_active,
462 	.is_compressing = g4x_fbc_is_compressing,
463 	.nuke = i965_fbc_nuke,
464 	.program_cfb = g4x_fbc_program_cfb,
465 };
466 
467 static void ilk_fbc_activate(struct intel_fbc *fbc)
468 {
469 	struct intel_fbc_state *fbc_state = &fbc->state;
470 	struct drm_i915_private *i915 = fbc->i915;
471 
472 	intel_de_write(i915, ILK_DPFC_FENCE_YOFF(fbc->id),
473 		       fbc_state->fence_y_offset);
474 
475 	intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id),
476 		       DPFC_CTL_EN | g4x_dpfc_ctl(fbc));
477 }
478 
479 static void ilk_fbc_deactivate(struct intel_fbc *fbc)
480 {
481 	struct drm_i915_private *i915 = fbc->i915;
482 	u32 dpfc_ctl;
483 
484 	/* Disable compression */
485 	dpfc_ctl = intel_de_read(i915, ILK_DPFC_CONTROL(fbc->id));
486 	if (dpfc_ctl & DPFC_CTL_EN) {
487 		dpfc_ctl &= ~DPFC_CTL_EN;
488 		intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id), dpfc_ctl);
489 	}
490 }
491 
492 static bool ilk_fbc_is_active(struct intel_fbc *fbc)
493 {
494 	return intel_de_read(fbc->i915, ILK_DPFC_CONTROL(fbc->id)) & DPFC_CTL_EN;
495 }
496 
497 static bool ilk_fbc_is_compressing(struct intel_fbc *fbc)
498 {
499 	return intel_de_read(fbc->i915, ILK_DPFC_STATUS(fbc->id)) & DPFC_COMP_SEG_MASK;
500 }
501 
502 static void ilk_fbc_program_cfb(struct intel_fbc *fbc)
503 {
504 	struct drm_i915_private *i915 = fbc->i915;
505 
506 	intel_de_write(i915, ILK_DPFC_CB_BASE(fbc->id),
507 		       i915_gem_stolen_node_offset(&fbc->compressed_fb));
508 }
509 
510 static const struct intel_fbc_funcs ilk_fbc_funcs = {
511 	.activate = ilk_fbc_activate,
512 	.deactivate = ilk_fbc_deactivate,
513 	.is_active = ilk_fbc_is_active,
514 	.is_compressing = ilk_fbc_is_compressing,
515 	.nuke = i965_fbc_nuke,
516 	.program_cfb = ilk_fbc_program_cfb,
517 };
518 
519 static void snb_fbc_program_fence(struct intel_fbc *fbc)
520 {
521 	const struct intel_fbc_state *fbc_state = &fbc->state;
522 	struct drm_i915_private *i915 = fbc->i915;
523 	u32 ctl = 0;
524 
525 	if (fbc_state->fence_id >= 0)
526 		ctl = SNB_DPFC_FENCE_EN | SNB_DPFC_FENCENO(fbc_state->fence_id);
527 
528 	intel_de_write(i915, SNB_DPFC_CTL_SA, ctl);
529 	intel_de_write(i915, SNB_DPFC_CPU_FENCE_OFFSET, fbc_state->fence_y_offset);
530 }
531 
532 static void snb_fbc_activate(struct intel_fbc *fbc)
533 {
534 	snb_fbc_program_fence(fbc);
535 
536 	ilk_fbc_activate(fbc);
537 }
538 
539 static void snb_fbc_nuke(struct intel_fbc *fbc)
540 {
541 	struct drm_i915_private *i915 = fbc->i915;
542 
543 	intel_de_write(i915, MSG_FBC_REND_STATE(fbc->id), FBC_REND_NUKE);
544 	intel_de_posting_read(i915, MSG_FBC_REND_STATE(fbc->id));
545 }
546 
547 static const struct intel_fbc_funcs snb_fbc_funcs = {
548 	.activate = snb_fbc_activate,
549 	.deactivate = ilk_fbc_deactivate,
550 	.is_active = ilk_fbc_is_active,
551 	.is_compressing = ilk_fbc_is_compressing,
552 	.nuke = snb_fbc_nuke,
553 	.program_cfb = ilk_fbc_program_cfb,
554 };
555 
556 static void glk_fbc_program_cfb_stride(struct intel_fbc *fbc)
557 {
558 	const struct intel_fbc_state *fbc_state = &fbc->state;
559 	struct drm_i915_private *i915 = fbc->i915;
560 	u32 val = 0;
561 
562 	if (fbc_state->override_cfb_stride)
563 		val |= FBC_STRIDE_OVERRIDE |
564 			FBC_STRIDE(fbc_state->override_cfb_stride / fbc->limit);
565 
566 	intel_de_write(i915, GLK_FBC_STRIDE(fbc->id), val);
567 }
568 
569 static void skl_fbc_program_cfb_stride(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 val = 0;
574 
575 	/* Display WA #0529: skl, kbl, bxt. */
576 	if (fbc_state->override_cfb_stride)
577 		val |= CHICKEN_FBC_STRIDE_OVERRIDE |
578 			CHICKEN_FBC_STRIDE(fbc_state->override_cfb_stride / fbc->limit);
579 
580 	intel_de_rmw(i915, CHICKEN_MISC_4,
581 		     CHICKEN_FBC_STRIDE_OVERRIDE |
582 		     CHICKEN_FBC_STRIDE_MASK, val);
583 }
584 
585 static u32 ivb_dpfc_ctl(struct intel_fbc *fbc)
586 {
587 	const struct intel_fbc_state *fbc_state = &fbc->state;
588 	struct drm_i915_private *i915 = fbc->i915;
589 	u32 dpfc_ctl;
590 
591 	dpfc_ctl = g4x_dpfc_ctl_limit(fbc);
592 
593 	if (IS_IVYBRIDGE(i915))
594 		dpfc_ctl |= DPFC_CTL_PLANE_IVB(fbc_state->plane->i9xx_plane);
595 
596 	if (DISPLAY_VER(i915) >= 20)
597 		dpfc_ctl |= DPFC_CTL_PLANE_BINDING(fbc_state->plane->id);
598 
599 	if (fbc_state->fence_id >= 0)
600 		dpfc_ctl |= DPFC_CTL_FENCE_EN_IVB;
601 
602 	if (fbc->false_color)
603 		dpfc_ctl |= DPFC_CTL_FALSE_COLOR;
604 
605 	return dpfc_ctl;
606 }
607 
608 static void ivb_fbc_activate(struct intel_fbc *fbc)
609 {
610 	struct drm_i915_private *i915 = fbc->i915;
611 	u32 dpfc_ctl;
612 
613 	if (DISPLAY_VER(i915) >= 10)
614 		glk_fbc_program_cfb_stride(fbc);
615 	else if (DISPLAY_VER(i915) == 9)
616 		skl_fbc_program_cfb_stride(fbc);
617 
618 	if (intel_gt_support_legacy_fencing(to_gt(i915)))
619 		snb_fbc_program_fence(fbc);
620 
621 	/* wa_14019417088 Alternative WA*/
622 	dpfc_ctl = ivb_dpfc_ctl(fbc);
623 	if (DISPLAY_VER(i915) >= 20)
624 		intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id), dpfc_ctl);
625 
626 	intel_de_write(i915, ILK_DPFC_CONTROL(fbc->id),
627 		       DPFC_CTL_EN | dpfc_ctl);
628 }
629 
630 static bool ivb_fbc_is_compressing(struct intel_fbc *fbc)
631 {
632 	return intel_de_read(fbc->i915, ILK_DPFC_STATUS2(fbc->id)) & DPFC_COMP_SEG_MASK_IVB;
633 }
634 
635 static void ivb_fbc_set_false_color(struct intel_fbc *fbc,
636 				    bool enable)
637 {
638 	intel_de_rmw(fbc->i915, ILK_DPFC_CONTROL(fbc->id),
639 		     DPFC_CTL_FALSE_COLOR, enable ? DPFC_CTL_FALSE_COLOR : 0);
640 }
641 
642 static const struct intel_fbc_funcs ivb_fbc_funcs = {
643 	.activate = ivb_fbc_activate,
644 	.deactivate = ilk_fbc_deactivate,
645 	.is_active = ilk_fbc_is_active,
646 	.is_compressing = ivb_fbc_is_compressing,
647 	.nuke = snb_fbc_nuke,
648 	.program_cfb = ilk_fbc_program_cfb,
649 	.set_false_color = ivb_fbc_set_false_color,
650 };
651 
652 static bool intel_fbc_hw_is_active(struct intel_fbc *fbc)
653 {
654 	return fbc->funcs->is_active(fbc);
655 }
656 
657 static void intel_fbc_hw_activate(struct intel_fbc *fbc)
658 {
659 	trace_intel_fbc_activate(fbc->state.plane);
660 
661 	fbc->active = true;
662 	fbc->activated = true;
663 
664 	fbc->funcs->activate(fbc);
665 }
666 
667 static void intel_fbc_hw_deactivate(struct intel_fbc *fbc)
668 {
669 	trace_intel_fbc_deactivate(fbc->state.plane);
670 
671 	fbc->active = false;
672 
673 	fbc->funcs->deactivate(fbc);
674 }
675 
676 static bool intel_fbc_is_compressing(struct intel_fbc *fbc)
677 {
678 	return fbc->funcs->is_compressing(fbc);
679 }
680 
681 static void intel_fbc_nuke(struct intel_fbc *fbc)
682 {
683 	struct drm_i915_private *i915 = fbc->i915;
684 
685 	lockdep_assert_held(&fbc->lock);
686 	drm_WARN_ON(&i915->drm, fbc->flip_pending);
687 
688 	trace_intel_fbc_nuke(fbc->state.plane);
689 
690 	fbc->funcs->nuke(fbc);
691 }
692 
693 static void intel_fbc_activate(struct intel_fbc *fbc)
694 {
695 	lockdep_assert_held(&fbc->lock);
696 
697 	intel_fbc_hw_activate(fbc);
698 	intel_fbc_nuke(fbc);
699 
700 	fbc->no_fbc_reason = NULL;
701 }
702 
703 static void intel_fbc_deactivate(struct intel_fbc *fbc, const char *reason)
704 {
705 	lockdep_assert_held(&fbc->lock);
706 
707 	if (fbc->active)
708 		intel_fbc_hw_deactivate(fbc);
709 
710 	fbc->no_fbc_reason = reason;
711 }
712 
713 static u64 intel_fbc_cfb_base_max(struct drm_i915_private *i915)
714 {
715 	if (DISPLAY_VER(i915) >= 5 || IS_G4X(i915))
716 		return BIT_ULL(28);
717 	else
718 		return BIT_ULL(32);
719 }
720 
721 static u64 intel_fbc_stolen_end(struct drm_i915_private *i915)
722 {
723 	u64 end;
724 
725 	/* The FBC hardware for BDW/SKL doesn't have access to the stolen
726 	 * reserved range size, so it always assumes the maximum (8mb) is used.
727 	 * If we enable FBC using a CFB on that memory range we'll get FIFO
728 	 * underruns, even if that range is not reserved by the BIOS. */
729 	if (IS_BROADWELL(i915) ||
730 	    (DISPLAY_VER(i915) == 9 && !IS_BROXTON(i915)))
731 		end = i915_gem_stolen_area_size(i915) - 8 * 1024 * 1024;
732 	else
733 		end = U64_MAX;
734 
735 	return min(end, intel_fbc_cfb_base_max(i915));
736 }
737 
738 static int intel_fbc_min_limit(const struct intel_plane_state *plane_state)
739 {
740 	return plane_state->hw.fb->format->cpp[0] == 2 ? 2 : 1;
741 }
742 
743 static int intel_fbc_max_limit(struct drm_i915_private *i915)
744 {
745 	/* WaFbcOnly1to1Ratio:ctg */
746 	if (IS_G4X(i915))
747 		return 1;
748 
749 	/*
750 	 * FBC2 can only do 1:1, 1:2, 1:4, we limit
751 	 * FBC1 to the same out of convenience.
752 	 */
753 	return 4;
754 }
755 
756 static int find_compression_limit(struct intel_fbc *fbc,
757 				  unsigned int size, int min_limit)
758 {
759 	struct drm_i915_private *i915 = fbc->i915;
760 	u64 end = intel_fbc_stolen_end(i915);
761 	int ret, limit = min_limit;
762 
763 	size /= limit;
764 
765 	/* Try to over-allocate to reduce reallocations and fragmentation. */
766 	ret = i915_gem_stolen_insert_node_in_range(i915, &fbc->compressed_fb,
767 						   size <<= 1, 4096, 0, end);
768 	if (ret == 0)
769 		return limit;
770 
771 	for (; limit <= intel_fbc_max_limit(i915); limit <<= 1) {
772 		ret = i915_gem_stolen_insert_node_in_range(i915, &fbc->compressed_fb,
773 							   size >>= 1, 4096, 0, end);
774 		if (ret == 0)
775 			return limit;
776 	}
777 
778 	return 0;
779 }
780 
781 static int intel_fbc_alloc_cfb(struct intel_fbc *fbc,
782 			       unsigned int size, int min_limit)
783 {
784 	struct drm_i915_private *i915 = fbc->i915;
785 	int ret;
786 
787 	drm_WARN_ON(&i915->drm,
788 		    i915_gem_stolen_node_allocated(&fbc->compressed_fb));
789 	drm_WARN_ON(&i915->drm,
790 		    i915_gem_stolen_node_allocated(&fbc->compressed_llb));
791 
792 	if (DISPLAY_VER(i915) < 5 && !IS_G4X(i915)) {
793 		ret = i915_gem_stolen_insert_node(i915, &fbc->compressed_llb,
794 						  4096, 4096);
795 		if (ret)
796 			goto err;
797 	}
798 
799 	ret = find_compression_limit(fbc, size, min_limit);
800 	if (!ret)
801 		goto err_llb;
802 	else if (ret > min_limit)
803 		drm_info_once(&i915->drm,
804 			      "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");
805 
806 	fbc->limit = ret;
807 
808 	drm_dbg_kms(&i915->drm,
809 		    "reserved %llu bytes of contiguous stolen space for FBC, limit: %d\n",
810 		    i915_gem_stolen_node_size(&fbc->compressed_fb), fbc->limit);
811 	return 0;
812 
813 err_llb:
814 	if (i915_gem_stolen_node_allocated(&fbc->compressed_llb))
815 		i915_gem_stolen_remove_node(i915, &fbc->compressed_llb);
816 err:
817 	if (i915_gem_stolen_initialized(i915))
818 		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);
819 	return -ENOSPC;
820 }
821 
822 static void intel_fbc_program_cfb(struct intel_fbc *fbc)
823 {
824 	fbc->funcs->program_cfb(fbc);
825 }
826 
827 static void intel_fbc_program_workarounds(struct intel_fbc *fbc)
828 {
829 	/* Wa_22014263786:icl,jsl,tgl,dg1,rkl,adls,adlp,mtl */
830 	if (DISPLAY_VER(fbc->i915) >= 11 && !IS_DG2(fbc->i915))
831 		intel_de_rmw(fbc->i915, ILK_DPFC_CHICKEN(fbc->id), 0,
832 			     DPFC_CHICKEN_FORCE_SLB_INVALIDATION);
833 }
834 
835 static void __intel_fbc_cleanup_cfb(struct intel_fbc *fbc)
836 {
837 	struct drm_i915_private *i915 = fbc->i915;
838 
839 	if (WARN_ON(intel_fbc_hw_is_active(fbc)))
840 		return;
841 
842 	if (i915_gem_stolen_node_allocated(&fbc->compressed_llb))
843 		i915_gem_stolen_remove_node(i915, &fbc->compressed_llb);
844 	if (i915_gem_stolen_node_allocated(&fbc->compressed_fb))
845 		i915_gem_stolen_remove_node(i915, &fbc->compressed_fb);
846 }
847 
848 void intel_fbc_cleanup(struct drm_i915_private *i915)
849 {
850 	struct intel_fbc *fbc;
851 	enum intel_fbc_id fbc_id;
852 
853 	for_each_intel_fbc(i915, fbc, fbc_id) {
854 		mutex_lock(&fbc->lock);
855 		__intel_fbc_cleanup_cfb(fbc);
856 		mutex_unlock(&fbc->lock);
857 
858 		kfree(fbc);
859 	}
860 }
861 
862 static bool i8xx_fbc_stride_is_valid(const struct intel_plane_state *plane_state)
863 {
864 	const struct drm_framebuffer *fb = plane_state->hw.fb;
865 	unsigned int stride = intel_fbc_plane_stride(plane_state) *
866 		fb->format->cpp[0];
867 
868 	return stride == 4096 || stride == 8192;
869 }
870 
871 static bool i965_fbc_stride_is_valid(const struct intel_plane_state *plane_state)
872 {
873 	const struct drm_framebuffer *fb = plane_state->hw.fb;
874 	unsigned int stride = intel_fbc_plane_stride(plane_state) *
875 		fb->format->cpp[0];
876 
877 	return stride >= 2048 && stride <= 16384;
878 }
879 
880 static bool g4x_fbc_stride_is_valid(const struct intel_plane_state *plane_state)
881 {
882 	return true;
883 }
884 
885 static bool skl_fbc_stride_is_valid(const struct intel_plane_state *plane_state)
886 {
887 	const struct drm_framebuffer *fb = plane_state->hw.fb;
888 	unsigned int stride = intel_fbc_plane_stride(plane_state) *
889 		fb->format->cpp[0];
890 
891 	/* Display WA #1105: skl,bxt,kbl,cfl,glk */
892 	if (fb->modifier == DRM_FORMAT_MOD_LINEAR && stride & 511)
893 		return false;
894 
895 	return true;
896 }
897 
898 static bool icl_fbc_stride_is_valid(const struct intel_plane_state *plane_state)
899 {
900 	return true;
901 }
902 
903 static bool stride_is_valid(const struct intel_plane_state *plane_state)
904 {
905 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
906 
907 	if (DISPLAY_VER(i915) >= 11)
908 		return icl_fbc_stride_is_valid(plane_state);
909 	else if (DISPLAY_VER(i915) >= 9)
910 		return skl_fbc_stride_is_valid(plane_state);
911 	else if (DISPLAY_VER(i915) >= 5 || IS_G4X(i915))
912 		return g4x_fbc_stride_is_valid(plane_state);
913 	else if (DISPLAY_VER(i915) == 4)
914 		return i965_fbc_stride_is_valid(plane_state);
915 	else
916 		return i8xx_fbc_stride_is_valid(plane_state);
917 }
918 
919 static bool i8xx_fbc_pixel_format_is_valid(const struct intel_plane_state *plane_state)
920 {
921 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
922 	const struct drm_framebuffer *fb = plane_state->hw.fb;
923 
924 	switch (fb->format->format) {
925 	case DRM_FORMAT_XRGB8888:
926 	case DRM_FORMAT_XBGR8888:
927 		return true;
928 	case DRM_FORMAT_XRGB1555:
929 	case DRM_FORMAT_RGB565:
930 		/* 16bpp not supported on gen2 */
931 		if (DISPLAY_VER(i915) == 2)
932 			return false;
933 		return true;
934 	default:
935 		return false;
936 	}
937 }
938 
939 static bool g4x_fbc_pixel_format_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->format->format) {
945 	case DRM_FORMAT_XRGB8888:
946 	case DRM_FORMAT_XBGR8888:
947 		return true;
948 	case DRM_FORMAT_RGB565:
949 		/* WaFbcOnly1to1Ratio:ctg */
950 		if (IS_G4X(i915))
951 			return false;
952 		return true;
953 	default:
954 		return false;
955 	}
956 }
957 
958 static bool lnl_fbc_pixel_format_is_valid(const struct intel_plane_state *plane_state)
959 {
960 	const struct drm_framebuffer *fb = plane_state->hw.fb;
961 
962 	switch (fb->format->format) {
963 	case DRM_FORMAT_XRGB8888:
964 	case DRM_FORMAT_XBGR8888:
965 	case DRM_FORMAT_ARGB8888:
966 	case DRM_FORMAT_ABGR8888:
967 	case DRM_FORMAT_RGB565:
968 		return true;
969 	default:
970 		return false;
971 	}
972 }
973 
974 static bool pixel_format_is_valid(const struct intel_plane_state *plane_state)
975 {
976 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
977 
978 	if (DISPLAY_VER(i915) >= 20)
979 		return lnl_fbc_pixel_format_is_valid(plane_state);
980 	else if (DISPLAY_VER(i915) >= 5 || IS_G4X(i915))
981 		return g4x_fbc_pixel_format_is_valid(plane_state);
982 	else
983 		return i8xx_fbc_pixel_format_is_valid(plane_state);
984 }
985 
986 static bool i8xx_fbc_rotation_is_valid(const struct intel_plane_state *plane_state)
987 {
988 	return plane_state->hw.rotation == DRM_MODE_ROTATE_0;
989 }
990 
991 static bool g4x_fbc_rotation_is_valid(const struct intel_plane_state *plane_state)
992 {
993 	return true;
994 }
995 
996 static bool skl_fbc_rotation_is_valid(const struct intel_plane_state *plane_state)
997 {
998 	const struct drm_framebuffer *fb = plane_state->hw.fb;
999 	unsigned int rotation = plane_state->hw.rotation;
1000 
1001 	if (fb->format->format == DRM_FORMAT_RGB565 &&
1002 	    drm_rotation_90_or_270(rotation))
1003 		return false;
1004 
1005 	return true;
1006 }
1007 
1008 static bool rotation_is_valid(const struct intel_plane_state *plane_state)
1009 {
1010 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
1011 
1012 	if (DISPLAY_VER(i915) >= 9)
1013 		return skl_fbc_rotation_is_valid(plane_state);
1014 	else if (DISPLAY_VER(i915) >= 5 || IS_G4X(i915))
1015 		return g4x_fbc_rotation_is_valid(plane_state);
1016 	else
1017 		return i8xx_fbc_rotation_is_valid(plane_state);
1018 }
1019 
1020 /*
1021  * For some reason, the hardware tracking starts looking at whatever we
1022  * programmed as the display plane base address register. It does not look at
1023  * the X and Y offset registers. That's why we include the src x/y offsets
1024  * instead of just looking at the plane size.
1025  */
1026 static bool intel_fbc_hw_tracking_covers_screen(const struct intel_plane_state *plane_state)
1027 {
1028 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
1029 	unsigned int effective_w, effective_h, max_w, max_h;
1030 
1031 	if (DISPLAY_VER(i915) >= 11) {
1032 		max_w = 8192;
1033 		max_h = 4096;
1034 	} else if (DISPLAY_VER(i915) >= 10) {
1035 		max_w = 5120;
1036 		max_h = 4096;
1037 	} else if (DISPLAY_VER(i915) >= 7) {
1038 		max_w = 4096;
1039 		max_h = 4096;
1040 	} else if (IS_G4X(i915) || DISPLAY_VER(i915) >= 5) {
1041 		max_w = 4096;
1042 		max_h = 2048;
1043 	} else {
1044 		max_w = 2048;
1045 		max_h = 1536;
1046 	}
1047 
1048 	effective_w = plane_state->view.color_plane[0].x +
1049 		(drm_rect_width(&plane_state->uapi.src) >> 16);
1050 	effective_h = plane_state->view.color_plane[0].y +
1051 		(drm_rect_height(&plane_state->uapi.src) >> 16);
1052 
1053 	return effective_w <= max_w && effective_h <= max_h;
1054 }
1055 
1056 static bool intel_fbc_plane_size_valid(const struct intel_plane_state *plane_state)
1057 {
1058 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
1059 	unsigned int w, h, max_w, max_h;
1060 
1061 	if (DISPLAY_VER(i915) >= 10) {
1062 		max_w = 5120;
1063 		max_h = 4096;
1064 	} else if (DISPLAY_VER(i915) >= 8 || IS_HASWELL(i915)) {
1065 		max_w = 4096;
1066 		max_h = 4096;
1067 	} else if (IS_G4X(i915) || DISPLAY_VER(i915) >= 5) {
1068 		max_w = 4096;
1069 		max_h = 2048;
1070 	} else {
1071 		max_w = 2048;
1072 		max_h = 1536;
1073 	}
1074 
1075 	w = drm_rect_width(&plane_state->uapi.src) >> 16;
1076 	h = drm_rect_height(&plane_state->uapi.src) >> 16;
1077 
1078 	return w <= max_w && h <= max_h;
1079 }
1080 
1081 static bool i8xx_fbc_tiling_valid(const struct intel_plane_state *plane_state)
1082 {
1083 	const struct drm_framebuffer *fb = plane_state->hw.fb;
1084 
1085 	return fb->modifier == I915_FORMAT_MOD_X_TILED;
1086 }
1087 
1088 static bool skl_fbc_tiling_valid(const struct intel_plane_state *plane_state)
1089 {
1090 	const struct drm_framebuffer *fb = plane_state->hw.fb;
1091 
1092 	switch (fb->modifier) {
1093 	case DRM_FORMAT_MOD_LINEAR:
1094 	case I915_FORMAT_MOD_Y_TILED:
1095 	case I915_FORMAT_MOD_Yf_TILED:
1096 	case I915_FORMAT_MOD_4_TILED:
1097 	case I915_FORMAT_MOD_X_TILED:
1098 		return true;
1099 	default:
1100 		return false;
1101 	}
1102 }
1103 
1104 static bool tiling_is_valid(const struct intel_plane_state *plane_state)
1105 {
1106 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
1107 
1108 	if (DISPLAY_VER(i915) >= 9)
1109 		return skl_fbc_tiling_valid(plane_state);
1110 	else
1111 		return i8xx_fbc_tiling_valid(plane_state);
1112 }
1113 
1114 static void intel_fbc_update_state(struct intel_atomic_state *state,
1115 				   struct intel_crtc *crtc,
1116 				   struct intel_plane *plane)
1117 {
1118 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1119 	const struct intel_crtc_state *crtc_state =
1120 		intel_atomic_get_new_crtc_state(state, crtc);
1121 	const struct intel_plane_state *plane_state =
1122 		intel_atomic_get_new_plane_state(state, plane);
1123 	struct intel_fbc *fbc = plane->fbc;
1124 	struct intel_fbc_state *fbc_state = &fbc->state;
1125 
1126 	WARN_ON(plane_state->no_fbc_reason);
1127 	WARN_ON(fbc_state->plane && fbc_state->plane != plane);
1128 
1129 	fbc_state->plane = plane;
1130 
1131 	/* FBC1 compression interval: arbitrary choice of 1 second */
1132 	fbc_state->interval = drm_mode_vrefresh(&crtc_state->hw.adjusted_mode);
1133 
1134 	fbc_state->fence_y_offset = intel_plane_fence_y_offset(plane_state);
1135 
1136 	drm_WARN_ON(&i915->drm, plane_state->flags & PLANE_HAS_FENCE &&
1137 		    !intel_gt_support_legacy_fencing(to_gt(i915)));
1138 
1139 	if (plane_state->flags & PLANE_HAS_FENCE)
1140 		fbc_state->fence_id =  i915_vma_fence_id(plane_state->ggtt_vma);
1141 	else
1142 		fbc_state->fence_id = -1;
1143 
1144 	fbc_state->cfb_stride = intel_fbc_cfb_stride(plane_state);
1145 	fbc_state->cfb_size = intel_fbc_cfb_size(plane_state);
1146 	fbc_state->override_cfb_stride = intel_fbc_override_cfb_stride(plane_state);
1147 }
1148 
1149 static bool intel_fbc_is_fence_ok(const struct intel_plane_state *plane_state)
1150 {
1151 	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
1152 
1153 	/*
1154 	 * The use of a CPU fence is one of two ways to detect writes by the
1155 	 * CPU to the scanout and trigger updates to the FBC.
1156 	 *
1157 	 * The other method is by software tracking (see
1158 	 * intel_fbc_invalidate/flush()), it will manually notify FBC and nuke
1159 	 * the current compressed buffer and recompress it.
1160 	 *
1161 	 * Note that is possible for a tiled surface to be unmappable (and
1162 	 * so have no fence associated with it) due to aperture constraints
1163 	 * at the time of pinning.
1164 	 */
1165 	return DISPLAY_VER(i915) >= 9 ||
1166 		(plane_state->flags & PLANE_HAS_FENCE &&
1167 		 i915_vma_fence_id(plane_state->ggtt_vma) != -1);
1168 }
1169 
1170 static bool intel_fbc_is_cfb_ok(const struct intel_plane_state *plane_state)
1171 {
1172 	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
1173 	struct intel_fbc *fbc = plane->fbc;
1174 
1175 	return intel_fbc_min_limit(plane_state) <= fbc->limit &&
1176 		intel_fbc_cfb_size(plane_state) <= fbc->limit *
1177 			i915_gem_stolen_node_size(&fbc->compressed_fb);
1178 }
1179 
1180 static bool intel_fbc_is_ok(const struct intel_plane_state *plane_state)
1181 {
1182 	return !plane_state->no_fbc_reason &&
1183 		intel_fbc_is_fence_ok(plane_state) &&
1184 		intel_fbc_is_cfb_ok(plane_state);
1185 }
1186 
1187 static int intel_fbc_check_plane(struct intel_atomic_state *state,
1188 				 struct intel_plane *plane)
1189 {
1190 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1191 	struct intel_plane_state *plane_state =
1192 		intel_atomic_get_new_plane_state(state, plane);
1193 	const struct drm_framebuffer *fb = plane_state->hw.fb;
1194 	struct intel_crtc *crtc = to_intel_crtc(plane_state->hw.crtc);
1195 	const struct intel_crtc_state *crtc_state;
1196 	struct intel_fbc *fbc = plane->fbc;
1197 
1198 	if (!fbc)
1199 		return 0;
1200 
1201 	if (!i915_gem_stolen_initialized(i915)) {
1202 		plane_state->no_fbc_reason = "stolen memory not initialised";
1203 		return 0;
1204 	}
1205 
1206 	if (intel_vgpu_active(i915)) {
1207 		plane_state->no_fbc_reason = "VGPU active";
1208 		return 0;
1209 	}
1210 
1211 	if (!i915->display.params.enable_fbc) {
1212 		plane_state->no_fbc_reason = "disabled per module param or by default";
1213 		return 0;
1214 	}
1215 
1216 	if (!plane_state->uapi.visible) {
1217 		plane_state->no_fbc_reason = "plane not visible";
1218 		return 0;
1219 	}
1220 
1221 	crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
1222 
1223 	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE) {
1224 		plane_state->no_fbc_reason = "interlaced mode not supported";
1225 		return 0;
1226 	}
1227 
1228 	if (crtc_state->double_wide) {
1229 		plane_state->no_fbc_reason = "double wide pipe not supported";
1230 		return 0;
1231 	}
1232 
1233 	/*
1234 	 * Display 12+ is not supporting FBC with PSR2.
1235 	 * Recommendation is to keep this combination disabled
1236 	 * Bspec: 50422 HSD: 14010260002
1237 	 */
1238 	if (IS_DISPLAY_VER(i915, 12, 14) && crtc_state->has_psr2) {
1239 		plane_state->no_fbc_reason = "PSR2 enabled";
1240 		return 0;
1241 	}
1242 
1243 	/* Wa_14016291713 */
1244 	if ((IS_DISPLAY_VER(i915, 12, 13) ||
1245 	     IS_DISPLAY_IP_STEP(i915, IP_VER(14, 0), STEP_A0, STEP_C0)) &&
1246 	    crtc_state->has_psr) {
1247 		plane_state->no_fbc_reason = "PSR1 enabled (Wa_14016291713)";
1248 		return 0;
1249 	}
1250 
1251 	if (!pixel_format_is_valid(plane_state)) {
1252 		plane_state->no_fbc_reason = "pixel format not supported";
1253 		return 0;
1254 	}
1255 
1256 	if (!tiling_is_valid(plane_state)) {
1257 		plane_state->no_fbc_reason = "tiling not supported";
1258 		return 0;
1259 	}
1260 
1261 	if (!rotation_is_valid(plane_state)) {
1262 		plane_state->no_fbc_reason = "rotation not supported";
1263 		return 0;
1264 	}
1265 
1266 	if (!stride_is_valid(plane_state)) {
1267 		plane_state->no_fbc_reason = "stride not supported";
1268 		return 0;
1269 	}
1270 
1271 	if (DISPLAY_VER(i915) < 20 &&
1272 	    plane_state->hw.pixel_blend_mode != DRM_MODE_BLEND_PIXEL_NONE &&
1273 	    fb->format->has_alpha) {
1274 		plane_state->no_fbc_reason = "per-pixel alpha not supported";
1275 		return 0;
1276 	}
1277 
1278 	if (!intel_fbc_plane_size_valid(plane_state)) {
1279 		plane_state->no_fbc_reason = "plane size too big";
1280 		return 0;
1281 	}
1282 
1283 	if (!intel_fbc_hw_tracking_covers_screen(plane_state)) {
1284 		plane_state->no_fbc_reason = "surface size too big";
1285 		return 0;
1286 	}
1287 
1288 	/*
1289 	 * Work around a problem on GEN9+ HW, where enabling FBC on a plane
1290 	 * having a Y offset that isn't divisible by 4 causes FIFO underrun
1291 	 * and screen flicker.
1292 	 */
1293 	if (DISPLAY_VER(i915) >= 9 &&
1294 	    plane_state->view.color_plane[0].y & 3) {
1295 		plane_state->no_fbc_reason = "plane start Y offset misaligned";
1296 		return 0;
1297 	}
1298 
1299 	/* Wa_22010751166: icl, ehl, tgl, dg1, rkl */
1300 	if (DISPLAY_VER(i915) >= 11 &&
1301 	    (plane_state->view.color_plane[0].y +
1302 	     (drm_rect_height(&plane_state->uapi.src) >> 16)) & 3) {
1303 		plane_state->no_fbc_reason = "plane end Y offset misaligned";
1304 		return 0;
1305 	}
1306 
1307 	/* WaFbcExceedCdClockThreshold:hsw,bdw */
1308 	if (IS_HASWELL(i915) || IS_BROADWELL(i915)) {
1309 		const struct intel_cdclk_state *cdclk_state;
1310 
1311 		cdclk_state = intel_atomic_get_cdclk_state(state);
1312 		if (IS_ERR(cdclk_state))
1313 			return PTR_ERR(cdclk_state);
1314 
1315 		if (crtc_state->pixel_rate >= cdclk_state->logical.cdclk * 95 / 100) {
1316 			plane_state->no_fbc_reason = "pixel rate too high";
1317 			return 0;
1318 		}
1319 	}
1320 
1321 	plane_state->no_fbc_reason = NULL;
1322 
1323 	return 0;
1324 }
1325 
1326 
1327 static bool intel_fbc_can_flip_nuke(struct intel_atomic_state *state,
1328 				    struct intel_crtc *crtc,
1329 				    struct intel_plane *plane)
1330 {
1331 	const struct intel_crtc_state *new_crtc_state =
1332 		intel_atomic_get_new_crtc_state(state, crtc);
1333 	const struct intel_plane_state *old_plane_state =
1334 		intel_atomic_get_old_plane_state(state, plane);
1335 	const struct intel_plane_state *new_plane_state =
1336 		intel_atomic_get_new_plane_state(state, plane);
1337 	const struct drm_framebuffer *old_fb = old_plane_state->hw.fb;
1338 	const struct drm_framebuffer *new_fb = new_plane_state->hw.fb;
1339 
1340 	if (intel_crtc_needs_modeset(new_crtc_state))
1341 		return false;
1342 
1343 	if (!intel_fbc_is_ok(old_plane_state) ||
1344 	    !intel_fbc_is_ok(new_plane_state))
1345 		return false;
1346 
1347 	if (old_fb->format->format != new_fb->format->format)
1348 		return false;
1349 
1350 	if (old_fb->modifier != new_fb->modifier)
1351 		return false;
1352 
1353 	if (intel_fbc_plane_stride(old_plane_state) !=
1354 	    intel_fbc_plane_stride(new_plane_state))
1355 		return false;
1356 
1357 	if (intel_fbc_cfb_stride(old_plane_state) !=
1358 	    intel_fbc_cfb_stride(new_plane_state))
1359 		return false;
1360 
1361 	if (intel_fbc_cfb_size(old_plane_state) !=
1362 	    intel_fbc_cfb_size(new_plane_state))
1363 		return false;
1364 
1365 	if (intel_fbc_override_cfb_stride(old_plane_state) !=
1366 	    intel_fbc_override_cfb_stride(new_plane_state))
1367 		return false;
1368 
1369 	return true;
1370 }
1371 
1372 static bool __intel_fbc_pre_update(struct intel_atomic_state *state,
1373 				   struct intel_crtc *crtc,
1374 				   struct intel_plane *plane)
1375 {
1376 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1377 	struct intel_fbc *fbc = plane->fbc;
1378 	bool need_vblank_wait = false;
1379 
1380 	lockdep_assert_held(&fbc->lock);
1381 
1382 	fbc->flip_pending = true;
1383 
1384 	if (intel_fbc_can_flip_nuke(state, crtc, plane))
1385 		return need_vblank_wait;
1386 
1387 	intel_fbc_deactivate(fbc, "update pending");
1388 
1389 	/*
1390 	 * Display WA #1198: glk+
1391 	 * Need an extra vblank wait between FBC disable and most plane
1392 	 * updates. Bspec says this is only needed for plane disable, but
1393 	 * that is not true. Touching most plane registers will cause the
1394 	 * corruption to appear. Also SKL/derivatives do not seem to be
1395 	 * affected.
1396 	 *
1397 	 * TODO: could optimize this a bit by sampling the frame
1398 	 * counter when we disable FBC (if it was already done earlier)
1399 	 * and skipping the extra vblank wait before the plane update
1400 	 * if at least one frame has already passed.
1401 	 */
1402 	if (fbc->activated && DISPLAY_VER(i915) >= 10)
1403 		need_vblank_wait = true;
1404 	fbc->activated = false;
1405 
1406 	return need_vblank_wait;
1407 }
1408 
1409 bool intel_fbc_pre_update(struct intel_atomic_state *state,
1410 			  struct intel_crtc *crtc)
1411 {
1412 	const struct intel_plane_state __maybe_unused *plane_state;
1413 	bool need_vblank_wait = false;
1414 	struct intel_plane *plane;
1415 	int i;
1416 
1417 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1418 		struct intel_fbc *fbc = plane->fbc;
1419 
1420 		if (!fbc || plane->pipe != crtc->pipe)
1421 			continue;
1422 
1423 		mutex_lock(&fbc->lock);
1424 
1425 		if (fbc->state.plane == plane)
1426 			need_vblank_wait |= __intel_fbc_pre_update(state, crtc, plane);
1427 
1428 		mutex_unlock(&fbc->lock);
1429 	}
1430 
1431 	return need_vblank_wait;
1432 }
1433 
1434 static void __intel_fbc_disable(struct intel_fbc *fbc)
1435 {
1436 	struct drm_i915_private *i915 = fbc->i915;
1437 	struct intel_plane *plane = fbc->state.plane;
1438 
1439 	lockdep_assert_held(&fbc->lock);
1440 	drm_WARN_ON(&i915->drm, fbc->active);
1441 
1442 	drm_dbg_kms(&i915->drm, "Disabling FBC on [PLANE:%d:%s]\n",
1443 		    plane->base.base.id, plane->base.name);
1444 
1445 	__intel_fbc_cleanup_cfb(fbc);
1446 
1447 	fbc->state.plane = NULL;
1448 	fbc->flip_pending = false;
1449 	fbc->busy_bits = 0;
1450 }
1451 
1452 static void __intel_fbc_post_update(struct intel_fbc *fbc)
1453 {
1454 	lockdep_assert_held(&fbc->lock);
1455 
1456 	fbc->flip_pending = false;
1457 	fbc->busy_bits = 0;
1458 
1459 	intel_fbc_activate(fbc);
1460 }
1461 
1462 void intel_fbc_post_update(struct intel_atomic_state *state,
1463 			   struct intel_crtc *crtc)
1464 {
1465 	const struct intel_plane_state __maybe_unused *plane_state;
1466 	struct intel_plane *plane;
1467 	int i;
1468 
1469 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1470 		struct intel_fbc *fbc = plane->fbc;
1471 
1472 		if (!fbc || plane->pipe != crtc->pipe)
1473 			continue;
1474 
1475 		mutex_lock(&fbc->lock);
1476 
1477 		if (fbc->state.plane == plane)
1478 			__intel_fbc_post_update(fbc);
1479 
1480 		mutex_unlock(&fbc->lock);
1481 	}
1482 }
1483 
1484 static unsigned int intel_fbc_get_frontbuffer_bit(struct intel_fbc *fbc)
1485 {
1486 	if (fbc->state.plane)
1487 		return fbc->state.plane->frontbuffer_bit;
1488 	else
1489 		return 0;
1490 }
1491 
1492 static void __intel_fbc_invalidate(struct intel_fbc *fbc,
1493 				   unsigned int frontbuffer_bits,
1494 				   enum fb_op_origin origin)
1495 {
1496 	if (origin == ORIGIN_FLIP || origin == ORIGIN_CURSOR_UPDATE)
1497 		return;
1498 
1499 	mutex_lock(&fbc->lock);
1500 
1501 	frontbuffer_bits &= intel_fbc_get_frontbuffer_bit(fbc);
1502 	if (!frontbuffer_bits)
1503 		goto out;
1504 
1505 	fbc->busy_bits |= frontbuffer_bits;
1506 	intel_fbc_deactivate(fbc, "frontbuffer write");
1507 
1508 out:
1509 	mutex_unlock(&fbc->lock);
1510 }
1511 
1512 void intel_fbc_invalidate(struct drm_i915_private *i915,
1513 			  unsigned int frontbuffer_bits,
1514 			  enum fb_op_origin origin)
1515 {
1516 	struct intel_fbc *fbc;
1517 	enum intel_fbc_id fbc_id;
1518 
1519 	for_each_intel_fbc(i915, fbc, fbc_id)
1520 		__intel_fbc_invalidate(fbc, frontbuffer_bits, origin);
1521 
1522 }
1523 
1524 static void __intel_fbc_flush(struct intel_fbc *fbc,
1525 			      unsigned int frontbuffer_bits,
1526 			      enum fb_op_origin origin)
1527 {
1528 	mutex_lock(&fbc->lock);
1529 
1530 	frontbuffer_bits &= intel_fbc_get_frontbuffer_bit(fbc);
1531 	if (!frontbuffer_bits)
1532 		goto out;
1533 
1534 	fbc->busy_bits &= ~frontbuffer_bits;
1535 
1536 	if (origin == ORIGIN_FLIP || origin == ORIGIN_CURSOR_UPDATE)
1537 		goto out;
1538 
1539 	if (fbc->busy_bits || fbc->flip_pending)
1540 		goto out;
1541 
1542 	if (fbc->active)
1543 		intel_fbc_nuke(fbc);
1544 	else
1545 		intel_fbc_activate(fbc);
1546 
1547 out:
1548 	mutex_unlock(&fbc->lock);
1549 }
1550 
1551 void intel_fbc_flush(struct drm_i915_private *i915,
1552 		     unsigned int frontbuffer_bits,
1553 		     enum fb_op_origin origin)
1554 {
1555 	struct intel_fbc *fbc;
1556 	enum intel_fbc_id fbc_id;
1557 
1558 	for_each_intel_fbc(i915, fbc, fbc_id)
1559 		__intel_fbc_flush(fbc, frontbuffer_bits, origin);
1560 }
1561 
1562 int intel_fbc_atomic_check(struct intel_atomic_state *state)
1563 {
1564 	struct intel_plane_state __maybe_unused *plane_state;
1565 	struct intel_plane *plane;
1566 	int i;
1567 
1568 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1569 		int ret;
1570 
1571 		ret = intel_fbc_check_plane(state, plane);
1572 		if (ret)
1573 			return ret;
1574 	}
1575 
1576 	return 0;
1577 }
1578 
1579 static void __intel_fbc_enable(struct intel_atomic_state *state,
1580 			       struct intel_crtc *crtc,
1581 			       struct intel_plane *plane)
1582 {
1583 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1584 	const struct intel_plane_state *plane_state =
1585 		intel_atomic_get_new_plane_state(state, plane);
1586 	struct intel_fbc *fbc = plane->fbc;
1587 
1588 	lockdep_assert_held(&fbc->lock);
1589 
1590 	if (fbc->state.plane) {
1591 		if (fbc->state.plane != plane)
1592 			return;
1593 
1594 		if (intel_fbc_is_ok(plane_state)) {
1595 			intel_fbc_update_state(state, crtc, plane);
1596 			return;
1597 		}
1598 
1599 		__intel_fbc_disable(fbc);
1600 	}
1601 
1602 	drm_WARN_ON(&i915->drm, fbc->active);
1603 
1604 	fbc->no_fbc_reason = plane_state->no_fbc_reason;
1605 	if (fbc->no_fbc_reason)
1606 		return;
1607 
1608 	if (!intel_fbc_is_fence_ok(plane_state)) {
1609 		fbc->no_fbc_reason = "framebuffer not fenced";
1610 		return;
1611 	}
1612 
1613 	if (fbc->underrun_detected) {
1614 		fbc->no_fbc_reason = "FIFO underrun";
1615 		return;
1616 	}
1617 
1618 	if (intel_fbc_alloc_cfb(fbc, intel_fbc_cfb_size(plane_state),
1619 				intel_fbc_min_limit(plane_state))) {
1620 		fbc->no_fbc_reason = "not enough stolen memory";
1621 		return;
1622 	}
1623 
1624 	drm_dbg_kms(&i915->drm, "Enabling FBC on [PLANE:%d:%s]\n",
1625 		    plane->base.base.id, plane->base.name);
1626 	fbc->no_fbc_reason = "FBC enabled but not active yet\n";
1627 
1628 	intel_fbc_update_state(state, crtc, plane);
1629 
1630 	intel_fbc_program_workarounds(fbc);
1631 	intel_fbc_program_cfb(fbc);
1632 }
1633 
1634 /**
1635  * intel_fbc_disable - disable FBC if it's associated with crtc
1636  * @crtc: the CRTC
1637  *
1638  * This function disables FBC if it's associated with the provided CRTC.
1639  */
1640 void intel_fbc_disable(struct intel_crtc *crtc)
1641 {
1642 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
1643 	struct intel_plane *plane;
1644 
1645 	for_each_intel_plane(&i915->drm, plane) {
1646 		struct intel_fbc *fbc = plane->fbc;
1647 
1648 		if (!fbc || plane->pipe != crtc->pipe)
1649 			continue;
1650 
1651 		mutex_lock(&fbc->lock);
1652 		if (fbc->state.plane == plane)
1653 			__intel_fbc_disable(fbc);
1654 		mutex_unlock(&fbc->lock);
1655 	}
1656 }
1657 
1658 void intel_fbc_update(struct intel_atomic_state *state,
1659 		      struct intel_crtc *crtc)
1660 {
1661 	const struct intel_crtc_state *crtc_state =
1662 		intel_atomic_get_new_crtc_state(state, crtc);
1663 	const struct intel_plane_state *plane_state;
1664 	struct intel_plane *plane;
1665 	int i;
1666 
1667 	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
1668 		struct intel_fbc *fbc = plane->fbc;
1669 
1670 		if (!fbc || plane->pipe != crtc->pipe)
1671 			continue;
1672 
1673 		mutex_lock(&fbc->lock);
1674 
1675 		if (intel_crtc_needs_fastset(crtc_state) &&
1676 		    plane_state->no_fbc_reason) {
1677 			if (fbc->state.plane == plane)
1678 				__intel_fbc_disable(fbc);
1679 		} else {
1680 			__intel_fbc_enable(state, crtc, plane);
1681 		}
1682 
1683 		mutex_unlock(&fbc->lock);
1684 	}
1685 }
1686 
1687 static void intel_fbc_underrun_work_fn(struct work_struct *work)
1688 {
1689 	struct intel_fbc *fbc = container_of(work, typeof(*fbc), underrun_work);
1690 	struct drm_i915_private *i915 = fbc->i915;
1691 
1692 	mutex_lock(&fbc->lock);
1693 
1694 	/* Maybe we were scheduled twice. */
1695 	if (fbc->underrun_detected || !fbc->state.plane)
1696 		goto out;
1697 
1698 	drm_dbg_kms(&i915->drm, "Disabling FBC due to FIFO underrun.\n");
1699 	fbc->underrun_detected = true;
1700 
1701 	intel_fbc_deactivate(fbc, "FIFO underrun");
1702 	if (!fbc->flip_pending)
1703 		intel_crtc_wait_for_next_vblank(intel_crtc_for_pipe(i915, fbc->state.plane->pipe));
1704 	__intel_fbc_disable(fbc);
1705 out:
1706 	mutex_unlock(&fbc->lock);
1707 }
1708 
1709 static void __intel_fbc_reset_underrun(struct intel_fbc *fbc)
1710 {
1711 	struct drm_i915_private *i915 = fbc->i915;
1712 
1713 	cancel_work_sync(&fbc->underrun_work);
1714 
1715 	mutex_lock(&fbc->lock);
1716 
1717 	if (fbc->underrun_detected) {
1718 		drm_dbg_kms(&i915->drm,
1719 			    "Re-allowing FBC after fifo underrun\n");
1720 		fbc->no_fbc_reason = "FIFO underrun cleared";
1721 	}
1722 
1723 	fbc->underrun_detected = false;
1724 	mutex_unlock(&fbc->lock);
1725 }
1726 
1727 /*
1728  * intel_fbc_reset_underrun - reset FBC fifo underrun status.
1729  * @i915: the i915 device
1730  *
1731  * See intel_fbc_handle_fifo_underrun_irq(). For automated testing we
1732  * want to re-enable FBC after an underrun to increase test coverage.
1733  */
1734 void intel_fbc_reset_underrun(struct drm_i915_private *i915)
1735 {
1736 	struct intel_fbc *fbc;
1737 	enum intel_fbc_id fbc_id;
1738 
1739 	for_each_intel_fbc(i915, fbc, fbc_id)
1740 		__intel_fbc_reset_underrun(fbc);
1741 }
1742 
1743 static void __intel_fbc_handle_fifo_underrun_irq(struct intel_fbc *fbc)
1744 {
1745 	/*
1746 	 * There's no guarantee that underrun_detected won't be set to true
1747 	 * right after this check and before the work is scheduled, but that's
1748 	 * not a problem since we'll check it again under the work function
1749 	 * while FBC is locked. This check here is just to prevent us from
1750 	 * unnecessarily scheduling the work, and it relies on the fact that we
1751 	 * never switch underrun_detect back to false after it's true.
1752 	 */
1753 	if (READ_ONCE(fbc->underrun_detected))
1754 		return;
1755 
1756 	queue_work(fbc->i915->unordered_wq, &fbc->underrun_work);
1757 }
1758 
1759 /**
1760  * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun
1761  * @i915: i915 device
1762  *
1763  * Without FBC, most underruns are harmless and don't really cause too many
1764  * problems, except for an annoying message on dmesg. With FBC, underruns can
1765  * become black screens or even worse, especially when paired with bad
1766  * watermarks. So in order for us to be on the safe side, completely disable FBC
1767  * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe
1768  * already suggests that watermarks may be bad, so try to be as safe as
1769  * possible.
1770  *
1771  * This function is called from the IRQ handler.
1772  */
1773 void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *i915)
1774 {
1775 	struct intel_fbc *fbc;
1776 	enum intel_fbc_id fbc_id;
1777 
1778 	for_each_intel_fbc(i915, fbc, fbc_id)
1779 		__intel_fbc_handle_fifo_underrun_irq(fbc);
1780 }
1781 
1782 /*
1783  * The DDX driver changes its behavior depending on the value it reads from
1784  * i915.enable_fbc, so sanitize it by translating the default value into either
1785  * 0 or 1 in order to allow it to know what's going on.
1786  *
1787  * Notice that this is done at driver initialization and we still allow user
1788  * space to change the value during runtime without sanitizing it again. IGT
1789  * relies on being able to change i915.enable_fbc at runtime.
1790  */
1791 static int intel_sanitize_fbc_option(struct drm_i915_private *i915)
1792 {
1793 	if (i915->display.params.enable_fbc >= 0)
1794 		return !!i915->display.params.enable_fbc;
1795 
1796 	if (!HAS_FBC(i915))
1797 		return 0;
1798 
1799 	if (IS_BROADWELL(i915) || DISPLAY_VER(i915) >= 9)
1800 		return 1;
1801 
1802 	return 0;
1803 }
1804 
1805 static bool need_fbc_vtd_wa(struct drm_i915_private *i915)
1806 {
1807 	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
1808 	if (i915_vtd_active(i915) &&
1809 	    (IS_SKYLAKE(i915) || IS_BROXTON(i915))) {
1810 		drm_info(&i915->drm,
1811 			 "Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
1812 		return true;
1813 	}
1814 
1815 	return false;
1816 }
1817 
1818 void intel_fbc_add_plane(struct intel_fbc *fbc, struct intel_plane *plane)
1819 {
1820 	plane->fbc = fbc;
1821 }
1822 
1823 static struct intel_fbc *intel_fbc_create(struct drm_i915_private *i915,
1824 					  enum intel_fbc_id fbc_id)
1825 {
1826 	struct intel_fbc *fbc;
1827 
1828 	fbc = kzalloc(sizeof(*fbc), GFP_KERNEL);
1829 	if (!fbc)
1830 		return NULL;
1831 
1832 	fbc->id = fbc_id;
1833 	fbc->i915 = i915;
1834 	INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn);
1835 	mutex_init(&fbc->lock);
1836 
1837 	if (DISPLAY_VER(i915) >= 7)
1838 		fbc->funcs = &ivb_fbc_funcs;
1839 	else if (DISPLAY_VER(i915) == 6)
1840 		fbc->funcs = &snb_fbc_funcs;
1841 	else if (DISPLAY_VER(i915) == 5)
1842 		fbc->funcs = &ilk_fbc_funcs;
1843 	else if (IS_G4X(i915))
1844 		fbc->funcs = &g4x_fbc_funcs;
1845 	else if (DISPLAY_VER(i915) == 4)
1846 		fbc->funcs = &i965_fbc_funcs;
1847 	else
1848 		fbc->funcs = &i8xx_fbc_funcs;
1849 
1850 	return fbc;
1851 }
1852 
1853 /**
1854  * intel_fbc_init - Initialize FBC
1855  * @i915: the i915 device
1856  *
1857  * This function might be called during PM init process.
1858  */
1859 void intel_fbc_init(struct drm_i915_private *i915)
1860 {
1861 	enum intel_fbc_id fbc_id;
1862 
1863 	if (need_fbc_vtd_wa(i915))
1864 		DISPLAY_RUNTIME_INFO(i915)->fbc_mask = 0;
1865 
1866 	i915->display.params.enable_fbc = intel_sanitize_fbc_option(i915);
1867 	drm_dbg_kms(&i915->drm, "Sanitized enable_fbc value: %d\n",
1868 		    i915->display.params.enable_fbc);
1869 
1870 	for_each_fbc_id(i915, fbc_id)
1871 		i915->display.fbc[fbc_id] = intel_fbc_create(i915, fbc_id);
1872 }
1873 
1874 /**
1875  * intel_fbc_sanitize - Sanitize FBC
1876  * @i915: the i915 device
1877  *
1878  * Make sure FBC is initially disabled since we have no
1879  * idea eg. into which parts of stolen it might be scribbling
1880  * into.
1881  */
1882 void intel_fbc_sanitize(struct drm_i915_private *i915)
1883 {
1884 	struct intel_fbc *fbc;
1885 	enum intel_fbc_id fbc_id;
1886 
1887 	for_each_intel_fbc(i915, fbc, fbc_id) {
1888 		if (intel_fbc_hw_is_active(fbc))
1889 			intel_fbc_hw_deactivate(fbc);
1890 	}
1891 }
1892 
1893 static int intel_fbc_debugfs_status_show(struct seq_file *m, void *unused)
1894 {
1895 	struct intel_fbc *fbc = m->private;
1896 	struct drm_i915_private *i915 = fbc->i915;
1897 	struct intel_plane *plane;
1898 	intel_wakeref_t wakeref;
1899 
1900 	drm_modeset_lock_all(&i915->drm);
1901 
1902 	wakeref = intel_runtime_pm_get(&i915->runtime_pm);
1903 	mutex_lock(&fbc->lock);
1904 
1905 	if (fbc->active) {
1906 		seq_puts(m, "FBC enabled\n");
1907 		seq_printf(m, "Compressing: %s\n",
1908 			   str_yes_no(intel_fbc_is_compressing(fbc)));
1909 	} else {
1910 		seq_printf(m, "FBC disabled: %s\n", fbc->no_fbc_reason);
1911 	}
1912 
1913 	for_each_intel_plane(&i915->drm, plane) {
1914 		const struct intel_plane_state *plane_state =
1915 			to_intel_plane_state(plane->base.state);
1916 
1917 		if (plane->fbc != fbc)
1918 			continue;
1919 
1920 		seq_printf(m, "%c [PLANE:%d:%s]: %s\n",
1921 			   fbc->state.plane == plane ? '*' : ' ',
1922 			   plane->base.base.id, plane->base.name,
1923 			   plane_state->no_fbc_reason ?: "FBC possible");
1924 	}
1925 
1926 	mutex_unlock(&fbc->lock);
1927 	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
1928 
1929 	drm_modeset_unlock_all(&i915->drm);
1930 
1931 	return 0;
1932 }
1933 
1934 DEFINE_SHOW_ATTRIBUTE(intel_fbc_debugfs_status);
1935 
1936 static int intel_fbc_debugfs_false_color_get(void *data, u64 *val)
1937 {
1938 	struct intel_fbc *fbc = data;
1939 
1940 	*val = fbc->false_color;
1941 
1942 	return 0;
1943 }
1944 
1945 static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
1946 {
1947 	struct intel_fbc *fbc = data;
1948 
1949 	mutex_lock(&fbc->lock);
1950 
1951 	fbc->false_color = val;
1952 
1953 	if (fbc->active)
1954 		fbc->funcs->set_false_color(fbc, fbc->false_color);
1955 
1956 	mutex_unlock(&fbc->lock);
1957 
1958 	return 0;
1959 }
1960 
1961 DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
1962 			 intel_fbc_debugfs_false_color_get,
1963 			 intel_fbc_debugfs_false_color_set,
1964 			 "%llu\n");
1965 
1966 static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
1967 				  struct dentry *parent)
1968 {
1969 	debugfs_create_file("i915_fbc_status", 0444, parent,
1970 			    fbc, &intel_fbc_debugfs_status_fops);
1971 
1972 	if (fbc->funcs->set_false_color)
1973 		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
1974 					   fbc, &intel_fbc_debugfs_false_color_fops);
1975 }
1976 
1977 void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
1978 {
1979 	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
1980 
1981 	if (plane->fbc)
1982 		intel_fbc_debugfs_add(plane->fbc, crtc->base.debugfs_entry);
1983 }
1984 
1985 /* FIXME: remove this once igt is on board with per-crtc stuff */
1986 void intel_fbc_debugfs_register(struct drm_i915_private *i915)
1987 {
1988 	struct drm_minor *minor = i915->drm.primary;
1989 	struct intel_fbc *fbc;
1990 
1991 	fbc = i915->display.fbc[INTEL_FBC_A];
1992 	if (fbc)
1993 		intel_fbc_debugfs_add(fbc, minor->debugfs_root);
1994 }
1995