xref: /linux/drivers/gpu/drm/i915/display/intel_bw.c (revision bf5802238dc181b1f7375d358af1d01cd72d1c11)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include <drm/drm_atomic_state_helper.h>
7 
8 #include "i915_drv.h"
9 #include "i915_reg.h"
10 #include "i915_utils.h"
11 #include "intel_atomic.h"
12 #include "intel_bw.h"
13 #include "intel_cdclk.h"
14 #include "intel_display_core.h"
15 #include "intel_display_types.h"
16 #include "skl_watermark.h"
17 #include "intel_mchbar_regs.h"
18 #include "intel_pcode.h"
19 
20 /* Parameters for Qclk Geyserville (QGV) */
21 struct intel_qgv_point {
22 	u16 dclk, t_rp, t_rdpre, t_rc, t_ras, t_rcd;
23 };
24 
25 struct intel_psf_gv_point {
26 	u8 clk; /* clock in multiples of 16.6666 MHz */
27 };
28 
29 struct intel_qgv_info {
30 	struct intel_qgv_point points[I915_NUM_QGV_POINTS];
31 	struct intel_psf_gv_point psf_points[I915_NUM_PSF_GV_POINTS];
32 	u8 num_points;
33 	u8 num_psf_points;
34 	u8 t_bl;
35 	u8 max_numchannels;
36 	u8 channel_width;
37 	u8 deinterleave;
38 };
39 
40 static int dg1_mchbar_read_qgv_point_info(struct drm_i915_private *dev_priv,
41 					  struct intel_qgv_point *sp,
42 					  int point)
43 {
44 	u32 dclk_ratio, dclk_reference;
45 	u32 val;
46 
47 	val = intel_uncore_read(&dev_priv->uncore, SA_PERF_STATUS_0_0_0_MCHBAR_PC);
48 	dclk_ratio = REG_FIELD_GET(DG1_QCLK_RATIO_MASK, val);
49 	if (val & DG1_QCLK_REFERENCE)
50 		dclk_reference = 6; /* 6 * 16.666 MHz = 100 MHz */
51 	else
52 		dclk_reference = 8; /* 8 * 16.666 MHz = 133 MHz */
53 	sp->dclk = DIV_ROUND_UP((16667 * dclk_ratio * dclk_reference) + 500, 1000);
54 
55 	val = intel_uncore_read(&dev_priv->uncore, SKL_MC_BIOS_DATA_0_0_0_MCHBAR_PCU);
56 	if (val & DG1_GEAR_TYPE)
57 		sp->dclk *= 2;
58 
59 	if (sp->dclk == 0)
60 		return -EINVAL;
61 
62 	val = intel_uncore_read(&dev_priv->uncore, MCHBAR_CH0_CR_TC_PRE_0_0_0_MCHBAR);
63 	sp->t_rp = REG_FIELD_GET(DG1_DRAM_T_RP_MASK, val);
64 	sp->t_rdpre = REG_FIELD_GET(DG1_DRAM_T_RDPRE_MASK, val);
65 
66 	val = intel_uncore_read(&dev_priv->uncore, MCHBAR_CH0_CR_TC_PRE_0_0_0_MCHBAR_HIGH);
67 	sp->t_rcd = REG_FIELD_GET(DG1_DRAM_T_RCD_MASK, val);
68 	sp->t_ras = REG_FIELD_GET(DG1_DRAM_T_RAS_MASK, val);
69 
70 	sp->t_rc = sp->t_rp + sp->t_ras;
71 
72 	return 0;
73 }
74 
75 static int icl_pcode_read_qgv_point_info(struct drm_i915_private *dev_priv,
76 					 struct intel_qgv_point *sp,
77 					 int point)
78 {
79 	u32 val = 0, val2 = 0;
80 	u16 dclk;
81 	int ret;
82 
83 	ret = snb_pcode_read(&dev_priv->uncore, ICL_PCODE_MEM_SUBSYSYSTEM_INFO |
84 			     ICL_PCODE_MEM_SS_READ_QGV_POINT_INFO(point),
85 			     &val, &val2);
86 	if (ret)
87 		return ret;
88 
89 	dclk = val & 0xffff;
90 	sp->dclk = DIV_ROUND_UP((16667 * dclk) + (DISPLAY_VER(dev_priv) >= 12 ? 500 : 0),
91 				1000);
92 	sp->t_rp = (val & 0xff0000) >> 16;
93 	sp->t_rcd = (val & 0xff000000) >> 24;
94 
95 	sp->t_rdpre = val2 & 0xff;
96 	sp->t_ras = (val2 & 0xff00) >> 8;
97 
98 	sp->t_rc = sp->t_rp + sp->t_ras;
99 
100 	return 0;
101 }
102 
103 static int adls_pcode_read_psf_gv_point_info(struct drm_i915_private *dev_priv,
104 					    struct intel_psf_gv_point *points)
105 {
106 	u32 val = 0;
107 	int ret;
108 	int i;
109 
110 	ret = snb_pcode_read(&dev_priv->uncore, ICL_PCODE_MEM_SUBSYSYSTEM_INFO |
111 			     ADL_PCODE_MEM_SS_READ_PSF_GV_INFO, &val, NULL);
112 	if (ret)
113 		return ret;
114 
115 	for (i = 0; i < I915_NUM_PSF_GV_POINTS; i++) {
116 		points[i].clk = val & 0xff;
117 		val >>= 8;
118 	}
119 
120 	return 0;
121 }
122 
123 static u16 icl_qgv_points_mask(struct drm_i915_private *i915)
124 {
125 	unsigned int num_psf_gv_points = i915->display.bw.max[0].num_psf_gv_points;
126 	unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points;
127 	u16 qgv_points = 0, psf_points = 0;
128 
129 	/*
130 	 * We can _not_ use the whole ADLS_QGV_PT_MASK here, as PCode rejects
131 	 * it with failure if we try masking any unadvertised points.
132 	 * So need to operate only with those returned from PCode.
133 	 */
134 	if (num_qgv_points > 0)
135 		qgv_points = GENMASK(num_qgv_points - 1, 0);
136 
137 	if (num_psf_gv_points > 0)
138 		psf_points = GENMASK(num_psf_gv_points - 1, 0);
139 
140 	return ICL_PCODE_REQ_QGV_PT(qgv_points) | ADLS_PCODE_REQ_PSF_PT(psf_points);
141 }
142 
143 static bool is_sagv_enabled(struct drm_i915_private *i915, u16 points_mask)
144 {
145 	return !is_power_of_2(~points_mask & icl_qgv_points_mask(i915) &
146 			      ICL_PCODE_REQ_QGV_PT_MASK);
147 }
148 
149 int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv,
150 				  u32 points_mask)
151 {
152 	int ret;
153 
154 	if (DISPLAY_VER(dev_priv) >= 14)
155 		return 0;
156 
157 	/* bspec says to keep retrying for at least 1 ms */
158 	ret = skl_pcode_request(&dev_priv->uncore, ICL_PCODE_SAGV_DE_MEM_SS_CONFIG,
159 				points_mask,
160 				ICL_PCODE_REP_QGV_MASK | ADLS_PCODE_REP_PSF_MASK,
161 				ICL_PCODE_REP_QGV_SAFE | ADLS_PCODE_REP_PSF_SAFE,
162 				1);
163 
164 	if (ret < 0) {
165 		drm_err(&dev_priv->drm, "Failed to disable qgv points (%d) points: 0x%x\n", ret, points_mask);
166 		return ret;
167 	}
168 
169 	dev_priv->display.sagv.status = is_sagv_enabled(dev_priv, points_mask) ?
170 		I915_SAGV_ENABLED : I915_SAGV_DISABLED;
171 
172 	return 0;
173 }
174 
175 static int mtl_read_qgv_point_info(struct drm_i915_private *dev_priv,
176 				   struct intel_qgv_point *sp, int point)
177 {
178 	u32 val, val2;
179 	u16 dclk;
180 
181 	val = intel_uncore_read(&dev_priv->uncore,
182 				MTL_MEM_SS_INFO_QGV_POINT_LOW(point));
183 	val2 = intel_uncore_read(&dev_priv->uncore,
184 				 MTL_MEM_SS_INFO_QGV_POINT_HIGH(point));
185 	dclk = REG_FIELD_GET(MTL_DCLK_MASK, val);
186 	sp->dclk = DIV_ROUND_CLOSEST(16667 * dclk, 1000);
187 	sp->t_rp = REG_FIELD_GET(MTL_TRP_MASK, val);
188 	sp->t_rcd = REG_FIELD_GET(MTL_TRCD_MASK, val);
189 
190 	sp->t_rdpre = REG_FIELD_GET(MTL_TRDPRE_MASK, val2);
191 	sp->t_ras = REG_FIELD_GET(MTL_TRAS_MASK, val2);
192 
193 	sp->t_rc = sp->t_rp + sp->t_ras;
194 
195 	return 0;
196 }
197 
198 static int
199 intel_read_qgv_point_info(struct drm_i915_private *dev_priv,
200 			  struct intel_qgv_point *sp,
201 			  int point)
202 {
203 	if (DISPLAY_VER(dev_priv) >= 14)
204 		return mtl_read_qgv_point_info(dev_priv, sp, point);
205 	else if (IS_DG1(dev_priv))
206 		return dg1_mchbar_read_qgv_point_info(dev_priv, sp, point);
207 	else
208 		return icl_pcode_read_qgv_point_info(dev_priv, sp, point);
209 }
210 
211 static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
212 			      struct intel_qgv_info *qi,
213 			      bool is_y_tile)
214 {
215 	const struct dram_info *dram_info = &dev_priv->dram_info;
216 	int i, ret;
217 
218 	qi->num_points = dram_info->num_qgv_points;
219 	qi->num_psf_points = dram_info->num_psf_gv_points;
220 
221 	if (DISPLAY_VER(dev_priv) >= 14) {
222 		switch (dram_info->type) {
223 		case INTEL_DRAM_DDR4:
224 			qi->t_bl = 4;
225 			qi->max_numchannels = 2;
226 			qi->channel_width = 64;
227 			qi->deinterleave = 2;
228 			break;
229 		case INTEL_DRAM_DDR5:
230 			qi->t_bl = 8;
231 			qi->max_numchannels = 4;
232 			qi->channel_width = 32;
233 			qi->deinterleave = 2;
234 			break;
235 		case INTEL_DRAM_LPDDR4:
236 		case INTEL_DRAM_LPDDR5:
237 			qi->t_bl = 16;
238 			qi->max_numchannels = 8;
239 			qi->channel_width = 16;
240 			qi->deinterleave = 4;
241 			break;
242 		default:
243 			MISSING_CASE(dram_info->type);
244 			return -EINVAL;
245 		}
246 	} else if (DISPLAY_VER(dev_priv) >= 12) {
247 		switch (dram_info->type) {
248 		case INTEL_DRAM_DDR4:
249 			qi->t_bl = is_y_tile ? 8 : 4;
250 			qi->max_numchannels = 2;
251 			qi->channel_width = 64;
252 			qi->deinterleave = is_y_tile ? 1 : 2;
253 			break;
254 		case INTEL_DRAM_DDR5:
255 			qi->t_bl = is_y_tile ? 16 : 8;
256 			qi->max_numchannels = 4;
257 			qi->channel_width = 32;
258 			qi->deinterleave = is_y_tile ? 1 : 2;
259 			break;
260 		case INTEL_DRAM_LPDDR4:
261 			if (IS_ROCKETLAKE(dev_priv)) {
262 				qi->t_bl = 8;
263 				qi->max_numchannels = 4;
264 				qi->channel_width = 32;
265 				qi->deinterleave = 2;
266 				break;
267 			}
268 			fallthrough;
269 		case INTEL_DRAM_LPDDR5:
270 			qi->t_bl = 16;
271 			qi->max_numchannels = 8;
272 			qi->channel_width = 16;
273 			qi->deinterleave = is_y_tile ? 2 : 4;
274 			break;
275 		default:
276 			qi->t_bl = 16;
277 			qi->max_numchannels = 1;
278 			break;
279 		}
280 	} else if (DISPLAY_VER(dev_priv) == 11) {
281 		qi->t_bl = dev_priv->dram_info.type == INTEL_DRAM_DDR4 ? 4 : 8;
282 		qi->max_numchannels = 1;
283 	}
284 
285 	if (drm_WARN_ON(&dev_priv->drm,
286 			qi->num_points > ARRAY_SIZE(qi->points)))
287 		qi->num_points = ARRAY_SIZE(qi->points);
288 
289 	for (i = 0; i < qi->num_points; i++) {
290 		struct intel_qgv_point *sp = &qi->points[i];
291 
292 		ret = intel_read_qgv_point_info(dev_priv, sp, i);
293 		if (ret)
294 			return ret;
295 
296 		drm_dbg_kms(&dev_priv->drm,
297 			    "QGV %d: DCLK=%d tRP=%d tRDPRE=%d tRAS=%d tRCD=%d tRC=%d\n",
298 			    i, sp->dclk, sp->t_rp, sp->t_rdpre, sp->t_ras,
299 			    sp->t_rcd, sp->t_rc);
300 	}
301 
302 	if (qi->num_psf_points > 0) {
303 		ret = adls_pcode_read_psf_gv_point_info(dev_priv, qi->psf_points);
304 		if (ret) {
305 			drm_err(&dev_priv->drm, "Failed to read PSF point data; PSF points will not be considered in bandwidth calculations.\n");
306 			qi->num_psf_points = 0;
307 		}
308 
309 		for (i = 0; i < qi->num_psf_points; i++)
310 			drm_dbg_kms(&dev_priv->drm,
311 				    "PSF GV %d: CLK=%d \n",
312 				    i, qi->psf_points[i].clk);
313 	}
314 
315 	return 0;
316 }
317 
318 static int adl_calc_psf_bw(int clk)
319 {
320 	/*
321 	 * clk is multiples of 16.666MHz (100/6)
322 	 * According to BSpec PSF GV bandwidth is
323 	 * calculated as BW = 64 * clk * 16.666Mhz
324 	 */
325 	return DIV_ROUND_CLOSEST(64 * clk * 100, 6);
326 }
327 
328 static int icl_sagv_max_dclk(const struct intel_qgv_info *qi)
329 {
330 	u16 dclk = 0;
331 	int i;
332 
333 	for (i = 0; i < qi->num_points; i++)
334 		dclk = max(dclk, qi->points[i].dclk);
335 
336 	return dclk;
337 }
338 
339 struct intel_sa_info {
340 	u16 displayrtids;
341 	u8 deburst, deprogbwlimit, derating;
342 };
343 
344 static const struct intel_sa_info icl_sa_info = {
345 	.deburst = 8,
346 	.deprogbwlimit = 25, /* GB/s */
347 	.displayrtids = 128,
348 	.derating = 10,
349 };
350 
351 static const struct intel_sa_info tgl_sa_info = {
352 	.deburst = 16,
353 	.deprogbwlimit = 34, /* GB/s */
354 	.displayrtids = 256,
355 	.derating = 10,
356 };
357 
358 static const struct intel_sa_info rkl_sa_info = {
359 	.deburst = 8,
360 	.deprogbwlimit = 20, /* GB/s */
361 	.displayrtids = 128,
362 	.derating = 10,
363 };
364 
365 static const struct intel_sa_info adls_sa_info = {
366 	.deburst = 16,
367 	.deprogbwlimit = 38, /* GB/s */
368 	.displayrtids = 256,
369 	.derating = 10,
370 };
371 
372 static const struct intel_sa_info adlp_sa_info = {
373 	.deburst = 16,
374 	.deprogbwlimit = 38, /* GB/s */
375 	.displayrtids = 256,
376 	.derating = 20,
377 };
378 
379 static const struct intel_sa_info mtl_sa_info = {
380 	.deburst = 32,
381 	.deprogbwlimit = 38, /* GB/s */
382 	.displayrtids = 256,
383 	.derating = 10,
384 };
385 
386 static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa)
387 {
388 	struct intel_qgv_info qi = {};
389 	bool is_y_tile = true; /* assume y tile may be used */
390 	int num_channels = max_t(u8, 1, dev_priv->dram_info.num_channels);
391 	int ipqdepth, ipqdepthpch = 16;
392 	int dclk_max;
393 	int maxdebw;
394 	int num_groups = ARRAY_SIZE(dev_priv->display.bw.max);
395 	int i, ret;
396 
397 	ret = icl_get_qgv_points(dev_priv, &qi, is_y_tile);
398 	if (ret) {
399 		drm_dbg_kms(&dev_priv->drm,
400 			    "Failed to get memory subsystem information, ignoring bandwidth limits");
401 		return ret;
402 	}
403 
404 	dclk_max = icl_sagv_max_dclk(&qi);
405 	maxdebw = min(sa->deprogbwlimit * 1000, dclk_max * 16 * 6 / 10);
406 	ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels);
407 	qi.deinterleave = DIV_ROUND_UP(num_channels, is_y_tile ? 4 : 2);
408 
409 	for (i = 0; i < num_groups; i++) {
410 		struct intel_bw_info *bi = &dev_priv->display.bw.max[i];
411 		int clpchgroup;
412 		int j;
413 
414 		clpchgroup = (sa->deburst * qi.deinterleave / num_channels) << i;
415 		bi->num_planes = (ipqdepth - clpchgroup) / clpchgroup + 1;
416 
417 		bi->num_qgv_points = qi.num_points;
418 		bi->num_psf_gv_points = qi.num_psf_points;
419 
420 		for (j = 0; j < qi.num_points; j++) {
421 			const struct intel_qgv_point *sp = &qi.points[j];
422 			int ct, bw;
423 
424 			/*
425 			 * Max row cycle time
426 			 *
427 			 * FIXME what is the logic behind the
428 			 * assumed burst length?
429 			 */
430 			ct = max_t(int, sp->t_rc, sp->t_rp + sp->t_rcd +
431 				   (clpchgroup - 1) * qi.t_bl + sp->t_rdpre);
432 			bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct);
433 
434 			bi->deratedbw[j] = min(maxdebw,
435 					       bw * (100 - sa->derating) / 100);
436 
437 			drm_dbg_kms(&dev_priv->drm,
438 				    "BW%d / QGV %d: num_planes=%d deratedbw=%u\n",
439 				    i, j, bi->num_planes, bi->deratedbw[j]);
440 		}
441 	}
442 	/*
443 	 * In case if SAGV is disabled in BIOS, we always get 1
444 	 * SAGV point, but we can't send PCode commands to restrict it
445 	 * as it will fail and pointless anyway.
446 	 */
447 	if (qi.num_points == 1)
448 		dev_priv->display.sagv.status = I915_SAGV_NOT_CONTROLLED;
449 	else
450 		dev_priv->display.sagv.status = I915_SAGV_ENABLED;
451 
452 	return 0;
453 }
454 
455 static int tgl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa)
456 {
457 	struct intel_qgv_info qi = {};
458 	const struct dram_info *dram_info = &dev_priv->dram_info;
459 	bool is_y_tile = true; /* assume y tile may be used */
460 	int num_channels = max_t(u8, 1, dev_priv->dram_info.num_channels);
461 	int ipqdepth, ipqdepthpch = 16;
462 	int dclk_max;
463 	int maxdebw, peakbw;
464 	int clperchgroup;
465 	int num_groups = ARRAY_SIZE(dev_priv->display.bw.max);
466 	int i, ret;
467 
468 	ret = icl_get_qgv_points(dev_priv, &qi, is_y_tile);
469 	if (ret) {
470 		drm_dbg_kms(&dev_priv->drm,
471 			    "Failed to get memory subsystem information, ignoring bandwidth limits");
472 		return ret;
473 	}
474 
475 	if (DISPLAY_VER(dev_priv) < 14 &&
476 	    (dram_info->type == INTEL_DRAM_LPDDR4 || dram_info->type == INTEL_DRAM_LPDDR5))
477 		num_channels *= 2;
478 
479 	qi.deinterleave = qi.deinterleave ? : DIV_ROUND_UP(num_channels, is_y_tile ? 4 : 2);
480 
481 	if (num_channels < qi.max_numchannels && DISPLAY_VER(dev_priv) >= 12)
482 		qi.deinterleave = max(DIV_ROUND_UP(qi.deinterleave, 2), 1);
483 
484 	if (DISPLAY_VER(dev_priv) >= 12 && num_channels > qi.max_numchannels)
485 		drm_warn(&dev_priv->drm, "Number of channels exceeds max number of channels.");
486 	if (qi.max_numchannels != 0)
487 		num_channels = min_t(u8, num_channels, qi.max_numchannels);
488 
489 	dclk_max = icl_sagv_max_dclk(&qi);
490 
491 	peakbw = num_channels * DIV_ROUND_UP(qi.channel_width, 8) * dclk_max;
492 	maxdebw = min(sa->deprogbwlimit * 1000, peakbw * 6 / 10); /* 60% */
493 
494 	ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels);
495 	/*
496 	 * clperchgroup = 4kpagespermempage * clperchperblock,
497 	 * clperchperblock = 8 / num_channels * interleave
498 	 */
499 	clperchgroup = 4 * DIV_ROUND_UP(8, num_channels) * qi.deinterleave;
500 
501 	for (i = 0; i < num_groups; i++) {
502 		struct intel_bw_info *bi = &dev_priv->display.bw.max[i];
503 		struct intel_bw_info *bi_next;
504 		int clpchgroup;
505 		int j;
506 
507 		clpchgroup = (sa->deburst * qi.deinterleave / num_channels) << i;
508 
509 		if (i < num_groups - 1) {
510 			bi_next = &dev_priv->display.bw.max[i + 1];
511 
512 			if (clpchgroup < clperchgroup)
513 				bi_next->num_planes = (ipqdepth - clpchgroup) /
514 						       clpchgroup + 1;
515 			else
516 				bi_next->num_planes = 0;
517 		}
518 
519 		bi->num_qgv_points = qi.num_points;
520 		bi->num_psf_gv_points = qi.num_psf_points;
521 
522 		for (j = 0; j < qi.num_points; j++) {
523 			const struct intel_qgv_point *sp = &qi.points[j];
524 			int ct, bw;
525 
526 			/*
527 			 * Max row cycle time
528 			 *
529 			 * FIXME what is the logic behind the
530 			 * assumed burst length?
531 			 */
532 			ct = max_t(int, sp->t_rc, sp->t_rp + sp->t_rcd +
533 				   (clpchgroup - 1) * qi.t_bl + sp->t_rdpre);
534 			bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct);
535 
536 			bi->deratedbw[j] = min(maxdebw,
537 					       bw * (100 - sa->derating) / 100);
538 			bi->peakbw[j] = DIV_ROUND_CLOSEST(sp->dclk *
539 							  num_channels *
540 							  qi.channel_width, 8);
541 
542 			drm_dbg_kms(&dev_priv->drm,
543 				    "BW%d / QGV %d: num_planes=%d deratedbw=%u peakbw: %u\n",
544 				    i, j, bi->num_planes, bi->deratedbw[j],
545 				    bi->peakbw[j]);
546 		}
547 
548 		for (j = 0; j < qi.num_psf_points; j++) {
549 			const struct intel_psf_gv_point *sp = &qi.psf_points[j];
550 
551 			bi->psf_bw[j] = adl_calc_psf_bw(sp->clk);
552 
553 			drm_dbg_kms(&dev_priv->drm,
554 				    "BW%d / PSF GV %d: num_planes=%d bw=%u\n",
555 				    i, j, bi->num_planes, bi->psf_bw[j]);
556 		}
557 	}
558 
559 	/*
560 	 * In case if SAGV is disabled in BIOS, we always get 1
561 	 * SAGV point, but we can't send PCode commands to restrict it
562 	 * as it will fail and pointless anyway.
563 	 */
564 	if (qi.num_points == 1)
565 		dev_priv->display.sagv.status = I915_SAGV_NOT_CONTROLLED;
566 	else
567 		dev_priv->display.sagv.status = I915_SAGV_ENABLED;
568 
569 	return 0;
570 }
571 
572 static void dg2_get_bw_info(struct drm_i915_private *i915)
573 {
574 	unsigned int deratedbw = IS_DG2_G11(i915) ? 38000 : 50000;
575 	int num_groups = ARRAY_SIZE(i915->display.bw.max);
576 	int i;
577 
578 	/*
579 	 * DG2 doesn't have SAGV or QGV points, just a constant max bandwidth
580 	 * that doesn't depend on the number of planes enabled. So fill all the
581 	 * plane group with constant bw information for uniformity with other
582 	 * platforms. DG2-G10 platforms have a constant 50 GB/s bandwidth,
583 	 * whereas DG2-G11 platforms have 38 GB/s.
584 	 */
585 	for (i = 0; i < num_groups; i++) {
586 		struct intel_bw_info *bi = &i915->display.bw.max[i];
587 
588 		bi->num_planes = 1;
589 		/* Need only one dummy QGV point per group */
590 		bi->num_qgv_points = 1;
591 		bi->deratedbw[0] = deratedbw;
592 	}
593 
594 	i915->display.sagv.status = I915_SAGV_NOT_CONTROLLED;
595 }
596 
597 static unsigned int icl_max_bw_index(struct drm_i915_private *dev_priv,
598 				     int num_planes, int qgv_point)
599 {
600 	int i;
601 
602 	/*
603 	 * Let's return max bw for 0 planes
604 	 */
605 	num_planes = max(1, num_planes);
606 
607 	for (i = 0; i < ARRAY_SIZE(dev_priv->display.bw.max); i++) {
608 		const struct intel_bw_info *bi =
609 			&dev_priv->display.bw.max[i];
610 
611 		/*
612 		 * Pcode will not expose all QGV points when
613 		 * SAGV is forced to off/min/med/max.
614 		 */
615 		if (qgv_point >= bi->num_qgv_points)
616 			return UINT_MAX;
617 
618 		if (num_planes >= bi->num_planes)
619 			return i;
620 	}
621 
622 	return UINT_MAX;
623 }
624 
625 static unsigned int tgl_max_bw_index(struct drm_i915_private *dev_priv,
626 				     int num_planes, int qgv_point)
627 {
628 	int i;
629 
630 	/*
631 	 * Let's return max bw for 0 planes
632 	 */
633 	num_planes = max(1, num_planes);
634 
635 	for (i = ARRAY_SIZE(dev_priv->display.bw.max) - 1; i >= 0; i--) {
636 		const struct intel_bw_info *bi =
637 			&dev_priv->display.bw.max[i];
638 
639 		/*
640 		 * Pcode will not expose all QGV points when
641 		 * SAGV is forced to off/min/med/max.
642 		 */
643 		if (qgv_point >= bi->num_qgv_points)
644 			return UINT_MAX;
645 
646 		if (num_planes <= bi->num_planes)
647 			return i;
648 	}
649 
650 	return 0;
651 }
652 
653 static unsigned int adl_psf_bw(struct drm_i915_private *dev_priv,
654 			       int psf_gv_point)
655 {
656 	const struct intel_bw_info *bi =
657 			&dev_priv->display.bw.max[0];
658 
659 	return bi->psf_bw[psf_gv_point];
660 }
661 
662 void intel_bw_init_hw(struct drm_i915_private *dev_priv)
663 {
664 	if (!HAS_DISPLAY(dev_priv))
665 		return;
666 
667 	if (DISPLAY_VER(dev_priv) >= 14)
668 		tgl_get_bw_info(dev_priv, &mtl_sa_info);
669 	else if (IS_DG2(dev_priv))
670 		dg2_get_bw_info(dev_priv);
671 	else if (IS_ALDERLAKE_P(dev_priv))
672 		tgl_get_bw_info(dev_priv, &adlp_sa_info);
673 	else if (IS_ALDERLAKE_S(dev_priv))
674 		tgl_get_bw_info(dev_priv, &adls_sa_info);
675 	else if (IS_ROCKETLAKE(dev_priv))
676 		tgl_get_bw_info(dev_priv, &rkl_sa_info);
677 	else if (DISPLAY_VER(dev_priv) == 12)
678 		tgl_get_bw_info(dev_priv, &tgl_sa_info);
679 	else if (DISPLAY_VER(dev_priv) == 11)
680 		icl_get_bw_info(dev_priv, &icl_sa_info);
681 }
682 
683 static unsigned int intel_bw_crtc_num_active_planes(const struct intel_crtc_state *crtc_state)
684 {
685 	/*
686 	 * We assume cursors are small enough
687 	 * to not not cause bandwidth problems.
688 	 */
689 	return hweight8(crtc_state->active_planes & ~BIT(PLANE_CURSOR));
690 }
691 
692 static unsigned int intel_bw_crtc_data_rate(const struct intel_crtc_state *crtc_state)
693 {
694 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
695 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
696 	unsigned int data_rate = 0;
697 	enum plane_id plane_id;
698 
699 	for_each_plane_id_on_crtc(crtc, plane_id) {
700 		/*
701 		 * We assume cursors are small enough
702 		 * to not not cause bandwidth problems.
703 		 */
704 		if (plane_id == PLANE_CURSOR)
705 			continue;
706 
707 		data_rate += crtc_state->data_rate[plane_id];
708 
709 		if (DISPLAY_VER(i915) < 11)
710 			data_rate += crtc_state->data_rate_y[plane_id];
711 	}
712 
713 	return data_rate;
714 }
715 
716 /* "Maximum Pipe Read Bandwidth" */
717 static int intel_bw_crtc_min_cdclk(const struct intel_crtc_state *crtc_state)
718 {
719 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
720 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
721 
722 	if (DISPLAY_VER(i915) < 12)
723 		return 0;
724 
725 	return DIV_ROUND_UP_ULL(mul_u32_u32(intel_bw_crtc_data_rate(crtc_state), 10), 512);
726 }
727 
728 void intel_bw_crtc_update(struct intel_bw_state *bw_state,
729 			  const struct intel_crtc_state *crtc_state)
730 {
731 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
732 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
733 
734 	bw_state->data_rate[crtc->pipe] =
735 		intel_bw_crtc_data_rate(crtc_state);
736 	bw_state->num_active_planes[crtc->pipe] =
737 		intel_bw_crtc_num_active_planes(crtc_state);
738 
739 	drm_dbg_kms(&i915->drm, "pipe %c data rate %u num active planes %u\n",
740 		    pipe_name(crtc->pipe),
741 		    bw_state->data_rate[crtc->pipe],
742 		    bw_state->num_active_planes[crtc->pipe]);
743 }
744 
745 static unsigned int intel_bw_num_active_planes(struct drm_i915_private *dev_priv,
746 					       const struct intel_bw_state *bw_state)
747 {
748 	unsigned int num_active_planes = 0;
749 	enum pipe pipe;
750 
751 	for_each_pipe(dev_priv, pipe)
752 		num_active_planes += bw_state->num_active_planes[pipe];
753 
754 	return num_active_planes;
755 }
756 
757 static unsigned int intel_bw_data_rate(struct drm_i915_private *dev_priv,
758 				       const struct intel_bw_state *bw_state)
759 {
760 	unsigned int data_rate = 0;
761 	enum pipe pipe;
762 
763 	for_each_pipe(dev_priv, pipe)
764 		data_rate += bw_state->data_rate[pipe];
765 
766 	if (DISPLAY_VER(dev_priv) >= 13 && i915_vtd_active(dev_priv))
767 		data_rate = DIV_ROUND_UP(data_rate * 105, 100);
768 
769 	return data_rate;
770 }
771 
772 struct intel_bw_state *
773 intel_atomic_get_old_bw_state(struct intel_atomic_state *state)
774 {
775 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
776 	struct intel_global_state *bw_state;
777 
778 	bw_state = intel_atomic_get_old_global_obj_state(state, &dev_priv->display.bw.obj);
779 
780 	return to_intel_bw_state(bw_state);
781 }
782 
783 struct intel_bw_state *
784 intel_atomic_get_new_bw_state(struct intel_atomic_state *state)
785 {
786 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
787 	struct intel_global_state *bw_state;
788 
789 	bw_state = intel_atomic_get_new_global_obj_state(state, &dev_priv->display.bw.obj);
790 
791 	return to_intel_bw_state(bw_state);
792 }
793 
794 struct intel_bw_state *
795 intel_atomic_get_bw_state(struct intel_atomic_state *state)
796 {
797 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
798 	struct intel_global_state *bw_state;
799 
800 	bw_state = intel_atomic_get_global_obj_state(state, &dev_priv->display.bw.obj);
801 	if (IS_ERR(bw_state))
802 		return ERR_CAST(bw_state);
803 
804 	return to_intel_bw_state(bw_state);
805 }
806 
807 static int mtl_find_qgv_points(struct drm_i915_private *i915,
808 			       unsigned int data_rate,
809 			       unsigned int num_active_planes,
810 			       struct intel_bw_state *new_bw_state)
811 {
812 	unsigned int best_rate = UINT_MAX;
813 	unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points;
814 	unsigned int qgv_peak_bw  = 0;
815 	int i;
816 	int ret;
817 
818 	ret = intel_atomic_lock_global_state(&new_bw_state->base);
819 	if (ret)
820 		return ret;
821 
822 	/*
823 	 * If SAGV cannot be enabled, disable the pcode SAGV by passing all 1's
824 	 * for qgv peak bw in PM Demand request. So assign UINT_MAX if SAGV is
825 	 * not enabled. PM Demand code will clamp the value for the register
826 	 */
827 	if (!intel_can_enable_sagv(i915, new_bw_state)) {
828 		new_bw_state->qgv_point_peakbw = U16_MAX;
829 		drm_dbg_kms(&i915->drm, "No SAGV, use UINT_MAX as peak bw.");
830 		return 0;
831 	}
832 
833 	/*
834 	 * Find the best QGV point by comparing the data_rate with max data rate
835 	 * offered per plane group
836 	 */
837 	for (i = 0; i < num_qgv_points; i++) {
838 		unsigned int bw_index =
839 			tgl_max_bw_index(i915, num_active_planes, i);
840 		unsigned int max_data_rate;
841 
842 		if (bw_index >= ARRAY_SIZE(i915->display.bw.max))
843 			continue;
844 
845 		max_data_rate = i915->display.bw.max[bw_index].deratedbw[i];
846 
847 		if (max_data_rate < data_rate)
848 			continue;
849 
850 		if (max_data_rate - data_rate < best_rate) {
851 			best_rate = max_data_rate - data_rate;
852 			qgv_peak_bw = i915->display.bw.max[bw_index].peakbw[i];
853 		}
854 
855 		drm_dbg_kms(&i915->drm, "QGV point %d: max bw %d required %d qgv_peak_bw: %d\n",
856 			    i, max_data_rate, data_rate, qgv_peak_bw);
857 	}
858 
859 	drm_dbg_kms(&i915->drm, "Matching peaks QGV bw: %d for required data rate: %d\n",
860 		    qgv_peak_bw, data_rate);
861 
862 	/*
863 	 * The display configuration cannot be supported if no QGV point
864 	 * satisfying the required data rate is found
865 	 */
866 	if (qgv_peak_bw == 0) {
867 		drm_dbg_kms(&i915->drm, "No QGV points for bw %d for display configuration(%d active planes).\n",
868 			    data_rate, num_active_planes);
869 		return -EINVAL;
870 	}
871 
872 	/* MTL PM DEMAND expects QGV BW parameter in multiples of 100 mbps */
873 	new_bw_state->qgv_point_peakbw = DIV_ROUND_CLOSEST(qgv_peak_bw, 100);
874 
875 	return 0;
876 }
877 
878 static int icl_find_qgv_points(struct drm_i915_private *i915,
879 			       unsigned int data_rate,
880 			       unsigned int num_active_planes,
881 			       const struct intel_bw_state *old_bw_state,
882 			       struct intel_bw_state *new_bw_state)
883 {
884 	unsigned int max_bw_point = 0;
885 	unsigned int max_bw = 0;
886 	unsigned int num_psf_gv_points = i915->display.bw.max[0].num_psf_gv_points;
887 	unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points;
888 	u16 psf_points = 0;
889 	u16 qgv_points = 0;
890 	int i;
891 	int ret;
892 
893 	ret = intel_atomic_lock_global_state(&new_bw_state->base);
894 	if (ret)
895 		return ret;
896 
897 	for (i = 0; i < num_qgv_points; i++) {
898 		unsigned int idx;
899 		unsigned int max_data_rate;
900 
901 		if (DISPLAY_VER(i915) >= 12)
902 			idx = tgl_max_bw_index(i915, num_active_planes, i);
903 		else
904 			idx = icl_max_bw_index(i915, num_active_planes, i);
905 
906 		if (idx >= ARRAY_SIZE(i915->display.bw.max))
907 			continue;
908 
909 		max_data_rate = i915->display.bw.max[idx].deratedbw[i];
910 
911 		/*
912 		 * We need to know which qgv point gives us
913 		 * maximum bandwidth in order to disable SAGV
914 		 * if we find that we exceed SAGV block time
915 		 * with watermarks. By that moment we already
916 		 * have those, as it is calculated earlier in
917 		 * intel_atomic_check,
918 		 */
919 		if (max_data_rate > max_bw) {
920 			max_bw_point = i;
921 			max_bw = max_data_rate;
922 		}
923 		if (max_data_rate >= data_rate)
924 			qgv_points |= BIT(i);
925 
926 		drm_dbg_kms(&i915->drm, "QGV point %d: max bw %d required %d\n",
927 			    i, max_data_rate, data_rate);
928 	}
929 
930 	for (i = 0; i < num_psf_gv_points; i++) {
931 		unsigned int max_data_rate = adl_psf_bw(i915, i);
932 
933 		if (max_data_rate >= data_rate)
934 			psf_points |= BIT(i);
935 
936 		drm_dbg_kms(&i915->drm, "PSF GV point %d: max bw %d"
937 			    " required %d\n",
938 			    i, max_data_rate, data_rate);
939 	}
940 
941 	/*
942 	 * BSpec states that we always should have at least one allowed point
943 	 * left, so if we couldn't - simply reject the configuration for obvious
944 	 * reasons.
945 	 */
946 	if (qgv_points == 0) {
947 		drm_dbg_kms(&i915->drm, "No QGV points provide sufficient memory"
948 			    " bandwidth %d for display configuration(%d active planes).\n",
949 			    data_rate, num_active_planes);
950 		return -EINVAL;
951 	}
952 
953 	if (num_psf_gv_points > 0 && psf_points == 0) {
954 		drm_dbg_kms(&i915->drm, "No PSF GV points provide sufficient memory"
955 			    " bandwidth %d for display configuration(%d active planes).\n",
956 			    data_rate, num_active_planes);
957 		return -EINVAL;
958 	}
959 
960 	/*
961 	 * Leave only single point with highest bandwidth, if
962 	 * we can't enable SAGV due to the increased memory latency it may
963 	 * cause.
964 	 */
965 	if (!intel_can_enable_sagv(i915, new_bw_state)) {
966 		qgv_points = BIT(max_bw_point);
967 		drm_dbg_kms(&i915->drm, "No SAGV, using single QGV point %d\n",
968 			    max_bw_point);
969 	}
970 
971 	/*
972 	 * We store the ones which need to be masked as that is what PCode
973 	 * actually accepts as a parameter.
974 	 */
975 	new_bw_state->qgv_points_mask =
976 		~(ICL_PCODE_REQ_QGV_PT(qgv_points) |
977 		  ADLS_PCODE_REQ_PSF_PT(psf_points)) &
978 		icl_qgv_points_mask(i915);
979 
980 	/*
981 	 * If the actual mask had changed we need to make sure that
982 	 * the commits are serialized(in case this is a nomodeset, nonblocking)
983 	 */
984 	if (new_bw_state->qgv_points_mask != old_bw_state->qgv_points_mask) {
985 		ret = intel_atomic_serialize_global_state(&new_bw_state->base);
986 		if (ret)
987 			return ret;
988 	}
989 
990 	return 0;
991 }
992 
993 static int intel_bw_check_qgv_points(struct drm_i915_private *i915,
994 				     const struct intel_bw_state *old_bw_state,
995 				     struct intel_bw_state *new_bw_state)
996 {
997 	unsigned int data_rate = intel_bw_data_rate(i915, new_bw_state);
998 	unsigned int num_active_planes =
999 			intel_bw_num_active_planes(i915, new_bw_state);
1000 
1001 	data_rate = DIV_ROUND_UP(data_rate, 1000);
1002 
1003 	if (DISPLAY_VER(i915) >= 14)
1004 		return mtl_find_qgv_points(i915, data_rate, num_active_planes,
1005 					   new_bw_state);
1006 	else
1007 		return icl_find_qgv_points(i915, data_rate, num_active_planes,
1008 					   old_bw_state, new_bw_state);
1009 }
1010 
1011 static bool intel_bw_state_changed(struct drm_i915_private *i915,
1012 				   const struct intel_bw_state *old_bw_state,
1013 				   const struct intel_bw_state *new_bw_state)
1014 {
1015 	enum pipe pipe;
1016 
1017 	for_each_pipe(i915, pipe) {
1018 		const struct intel_dbuf_bw *old_crtc_bw =
1019 			&old_bw_state->dbuf_bw[pipe];
1020 		const struct intel_dbuf_bw *new_crtc_bw =
1021 			&new_bw_state->dbuf_bw[pipe];
1022 		enum dbuf_slice slice;
1023 
1024 		for_each_dbuf_slice(i915, slice) {
1025 			if (old_crtc_bw->max_bw[slice] != new_crtc_bw->max_bw[slice] ||
1026 			    old_crtc_bw->active_planes[slice] != new_crtc_bw->active_planes[slice])
1027 				return true;
1028 		}
1029 
1030 		if (old_bw_state->min_cdclk[pipe] != new_bw_state->min_cdclk[pipe])
1031 			return true;
1032 	}
1033 
1034 	return false;
1035 }
1036 
1037 static void skl_plane_calc_dbuf_bw(struct intel_bw_state *bw_state,
1038 				   struct intel_crtc *crtc,
1039 				   enum plane_id plane_id,
1040 				   const struct skl_ddb_entry *ddb,
1041 				   unsigned int data_rate)
1042 {
1043 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
1044 	struct intel_dbuf_bw *crtc_bw = &bw_state->dbuf_bw[crtc->pipe];
1045 	unsigned int dbuf_mask = skl_ddb_dbuf_slice_mask(i915, ddb);
1046 	enum dbuf_slice slice;
1047 
1048 	/*
1049 	 * The arbiter can only really guarantee an
1050 	 * equal share of the total bw to each plane.
1051 	 */
1052 	for_each_dbuf_slice_in_mask(i915, slice, dbuf_mask) {
1053 		crtc_bw->max_bw[slice] = max(crtc_bw->max_bw[slice], data_rate);
1054 		crtc_bw->active_planes[slice] |= BIT(plane_id);
1055 	}
1056 }
1057 
1058 static void skl_crtc_calc_dbuf_bw(struct intel_bw_state *bw_state,
1059 				  const struct intel_crtc_state *crtc_state)
1060 {
1061 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
1062 	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
1063 	struct intel_dbuf_bw *crtc_bw = &bw_state->dbuf_bw[crtc->pipe];
1064 	enum plane_id plane_id;
1065 
1066 	memset(crtc_bw, 0, sizeof(*crtc_bw));
1067 
1068 	if (!crtc_state->hw.active)
1069 		return;
1070 
1071 	for_each_plane_id_on_crtc(crtc, plane_id) {
1072 		/*
1073 		 * We assume cursors are small enough
1074 		 * to not cause bandwidth problems.
1075 		 */
1076 		if (plane_id == PLANE_CURSOR)
1077 			continue;
1078 
1079 		skl_plane_calc_dbuf_bw(bw_state, crtc, plane_id,
1080 				       &crtc_state->wm.skl.plane_ddb[plane_id],
1081 				       crtc_state->data_rate[plane_id]);
1082 
1083 		if (DISPLAY_VER(i915) < 11)
1084 			skl_plane_calc_dbuf_bw(bw_state, crtc, plane_id,
1085 					       &crtc_state->wm.skl.plane_ddb_y[plane_id],
1086 					       crtc_state->data_rate[plane_id]);
1087 	}
1088 }
1089 
1090 /* "Maximum Data Buffer Bandwidth" */
1091 static int
1092 intel_bw_dbuf_min_cdclk(struct drm_i915_private *i915,
1093 			const struct intel_bw_state *bw_state)
1094 {
1095 	unsigned int total_max_bw = 0;
1096 	enum dbuf_slice slice;
1097 
1098 	for_each_dbuf_slice(i915, slice) {
1099 		int num_active_planes = 0;
1100 		unsigned int max_bw = 0;
1101 		enum pipe pipe;
1102 
1103 		/*
1104 		 * The arbiter can only really guarantee an
1105 		 * equal share of the total bw to each plane.
1106 		 */
1107 		for_each_pipe(i915, pipe) {
1108 			const struct intel_dbuf_bw *crtc_bw = &bw_state->dbuf_bw[pipe];
1109 
1110 			max_bw = max(crtc_bw->max_bw[slice], max_bw);
1111 			num_active_planes += hweight8(crtc_bw->active_planes[slice]);
1112 		}
1113 		max_bw *= num_active_planes;
1114 
1115 		total_max_bw = max(total_max_bw, max_bw);
1116 	}
1117 
1118 	return DIV_ROUND_UP(total_max_bw, 64);
1119 }
1120 
1121 int intel_bw_min_cdclk(struct drm_i915_private *i915,
1122 		       const struct intel_bw_state *bw_state)
1123 {
1124 	enum pipe pipe;
1125 	int min_cdclk;
1126 
1127 	min_cdclk = intel_bw_dbuf_min_cdclk(i915, bw_state);
1128 
1129 	for_each_pipe(i915, pipe)
1130 		min_cdclk = max(bw_state->min_cdclk[pipe], min_cdclk);
1131 
1132 	return min_cdclk;
1133 }
1134 
1135 int intel_bw_calc_min_cdclk(struct intel_atomic_state *state,
1136 			    bool *need_cdclk_calc)
1137 {
1138 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
1139 	struct intel_bw_state *new_bw_state = NULL;
1140 	const struct intel_bw_state *old_bw_state = NULL;
1141 	const struct intel_cdclk_state *cdclk_state;
1142 	const struct intel_crtc_state *crtc_state;
1143 	int old_min_cdclk, new_min_cdclk;
1144 	struct intel_crtc *crtc;
1145 	int i;
1146 
1147 	if (DISPLAY_VER(dev_priv) < 9)
1148 		return 0;
1149 
1150 	for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {
1151 		new_bw_state = intel_atomic_get_bw_state(state);
1152 		if (IS_ERR(new_bw_state))
1153 			return PTR_ERR(new_bw_state);
1154 
1155 		old_bw_state = intel_atomic_get_old_bw_state(state);
1156 
1157 		skl_crtc_calc_dbuf_bw(new_bw_state, crtc_state);
1158 
1159 		new_bw_state->min_cdclk[crtc->pipe] =
1160 			intel_bw_crtc_min_cdclk(crtc_state);
1161 	}
1162 
1163 	if (!old_bw_state)
1164 		return 0;
1165 
1166 	if (intel_bw_state_changed(dev_priv, old_bw_state, new_bw_state)) {
1167 		int ret = intel_atomic_lock_global_state(&new_bw_state->base);
1168 		if (ret)
1169 			return ret;
1170 	}
1171 
1172 	old_min_cdclk = intel_bw_min_cdclk(dev_priv, old_bw_state);
1173 	new_min_cdclk = intel_bw_min_cdclk(dev_priv, new_bw_state);
1174 
1175 	/*
1176 	 * No need to check against the cdclk state if
1177 	 * the min cdclk doesn't increase.
1178 	 *
1179 	 * Ie. we only ever increase the cdclk due to bandwidth
1180 	 * requirements. This can reduce back and forth
1181 	 * display blinking due to constant cdclk changes.
1182 	 */
1183 	if (new_min_cdclk <= old_min_cdclk)
1184 		return 0;
1185 
1186 	cdclk_state = intel_atomic_get_cdclk_state(state);
1187 	if (IS_ERR(cdclk_state))
1188 		return PTR_ERR(cdclk_state);
1189 
1190 	/*
1191 	 * No need to recalculate the cdclk state if
1192 	 * the min cdclk doesn't increase.
1193 	 *
1194 	 * Ie. we only ever increase the cdclk due to bandwidth
1195 	 * requirements. This can reduce back and forth
1196 	 * display blinking due to constant cdclk changes.
1197 	 */
1198 	if (new_min_cdclk <= cdclk_state->bw_min_cdclk)
1199 		return 0;
1200 
1201 	drm_dbg_kms(&dev_priv->drm,
1202 		    "new bandwidth min cdclk (%d kHz) > old min cdclk (%d kHz)\n",
1203 		    new_min_cdclk, cdclk_state->bw_min_cdclk);
1204 	*need_cdclk_calc = true;
1205 
1206 	return 0;
1207 }
1208 
1209 static int intel_bw_check_data_rate(struct intel_atomic_state *state, bool *changed)
1210 {
1211 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1212 	const struct intel_crtc_state *new_crtc_state, *old_crtc_state;
1213 	struct intel_crtc *crtc;
1214 	int i;
1215 
1216 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
1217 					    new_crtc_state, i) {
1218 		unsigned int old_data_rate =
1219 			intel_bw_crtc_data_rate(old_crtc_state);
1220 		unsigned int new_data_rate =
1221 			intel_bw_crtc_data_rate(new_crtc_state);
1222 		unsigned int old_active_planes =
1223 			intel_bw_crtc_num_active_planes(old_crtc_state);
1224 		unsigned int new_active_planes =
1225 			intel_bw_crtc_num_active_planes(new_crtc_state);
1226 		struct intel_bw_state *new_bw_state;
1227 
1228 		/*
1229 		 * Avoid locking the bw state when
1230 		 * nothing significant has changed.
1231 		 */
1232 		if (old_data_rate == new_data_rate &&
1233 		    old_active_planes == new_active_planes)
1234 			continue;
1235 
1236 		new_bw_state = intel_atomic_get_bw_state(state);
1237 		if (IS_ERR(new_bw_state))
1238 			return PTR_ERR(new_bw_state);
1239 
1240 		new_bw_state->data_rate[crtc->pipe] = new_data_rate;
1241 		new_bw_state->num_active_planes[crtc->pipe] = new_active_planes;
1242 
1243 		*changed = true;
1244 
1245 		drm_dbg_kms(&i915->drm,
1246 			    "[CRTC:%d:%s] data rate %u num active planes %u\n",
1247 			    crtc->base.base.id, crtc->base.name,
1248 			    new_bw_state->data_rate[crtc->pipe],
1249 			    new_bw_state->num_active_planes[crtc->pipe]);
1250 	}
1251 
1252 	return 0;
1253 }
1254 
1255 int intel_bw_atomic_check(struct intel_atomic_state *state)
1256 {
1257 	bool changed = false;
1258 	struct drm_i915_private *i915 = to_i915(state->base.dev);
1259 	struct intel_bw_state *new_bw_state;
1260 	const struct intel_bw_state *old_bw_state;
1261 	int ret;
1262 
1263 	/* FIXME earlier gens need some checks too */
1264 	if (DISPLAY_VER(i915) < 11)
1265 		return 0;
1266 
1267 	ret = intel_bw_check_data_rate(state, &changed);
1268 	if (ret)
1269 		return ret;
1270 
1271 	old_bw_state = intel_atomic_get_old_bw_state(state);
1272 	new_bw_state = intel_atomic_get_new_bw_state(state);
1273 
1274 	if (new_bw_state &&
1275 	    intel_can_enable_sagv(i915, old_bw_state) !=
1276 	    intel_can_enable_sagv(i915, new_bw_state))
1277 		changed = true;
1278 
1279 	/*
1280 	 * If none of our inputs (data rates, number of active
1281 	 * planes, SAGV yes/no) changed then nothing to do here.
1282 	 */
1283 	if (!changed)
1284 		return 0;
1285 
1286 	ret = intel_bw_check_qgv_points(i915, old_bw_state, new_bw_state);
1287 	if (ret)
1288 		return ret;
1289 
1290 	return 0;
1291 }
1292 
1293 static struct intel_global_state *
1294 intel_bw_duplicate_state(struct intel_global_obj *obj)
1295 {
1296 	struct intel_bw_state *state;
1297 
1298 	state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
1299 	if (!state)
1300 		return NULL;
1301 
1302 	return &state->base;
1303 }
1304 
1305 static void intel_bw_destroy_state(struct intel_global_obj *obj,
1306 				   struct intel_global_state *state)
1307 {
1308 	kfree(state);
1309 }
1310 
1311 static const struct intel_global_state_funcs intel_bw_funcs = {
1312 	.atomic_duplicate_state = intel_bw_duplicate_state,
1313 	.atomic_destroy_state = intel_bw_destroy_state,
1314 };
1315 
1316 int intel_bw_init(struct drm_i915_private *dev_priv)
1317 {
1318 	struct intel_bw_state *state;
1319 
1320 	state = kzalloc(sizeof(*state), GFP_KERNEL);
1321 	if (!state)
1322 		return -ENOMEM;
1323 
1324 	intel_atomic_global_obj_init(dev_priv, &dev_priv->display.bw.obj,
1325 				     &state->base, &intel_bw_funcs);
1326 
1327 	return 0;
1328 }
1329