xref: /linux/drivers/gpu/drm/i915/display/skl_scaler.c (revision cbac924200b838cfb8d8b1415113d788089dc50b)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 #include "intel_de.h"
6 #include "intel_display_types.h"
7 #include "intel_fb.h"
8 #include "skl_scaler.h"
9 #include "skl_universal_plane.h"
10 
11 /*
12  * The hardware phase 0.0 refers to the center of the pixel.
13  * We want to start from the top/left edge which is phase
14  * -0.5. That matches how the hardware calculates the scaling
15  * factors (from top-left of the first pixel to bottom-right
16  * of the last pixel, as opposed to the pixel centers).
17  *
18  * For 4:2:0 subsampled chroma planes we obviously have to
19  * adjust that so that the chroma sample position lands in
20  * the right spot.
21  *
22  * Note that for packed YCbCr 4:2:2 formats there is no way to
23  * control chroma siting. The hardware simply replicates the
24  * chroma samples for both of the luma samples, and thus we don't
25  * actually get the expected MPEG2 chroma siting convention :(
26  * The same behaviour is observed on pre-SKL platforms as well.
27  *
28  * Theory behind the formula (note that we ignore sub-pixel
29  * source coordinates):
30  * s = source sample position
31  * d = destination sample position
32  *
33  * Downscaling 4:1:
34  * -0.5
35  * | 0.0
36  * | |     1.5 (initial phase)
37  * | |     |
38  * v v     v
39  * | s | s | s | s |
40  * |       d       |
41  *
42  * Upscaling 1:4:
43  * -0.5
44  * | -0.375 (initial phase)
45  * | |     0.0
46  * | |     |
47  * v v     v
48  * |       s       |
49  * | d | d | d | d |
50  */
51 static u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_cosited)
52 {
53 	int phase = -0x8000;
54 	u16 trip = 0;
55 
56 	if (chroma_cosited)
57 		phase += (sub - 1) * 0x8000 / sub;
58 
59 	phase += scale / (2 * sub);
60 
61 	/*
62 	 * Hardware initial phase limited to [-0.5:1.5].
63 	 * Since the max hardware scale factor is 3.0, we
64 	 * should never actually excdeed 1.0 here.
65 	 */
66 	WARN_ON(phase < -0x8000 || phase > 0x18000);
67 
68 	if (phase < 0)
69 		phase = 0x10000 + phase;
70 	else
71 		trip = PS_PHASE_TRIP;
72 
73 	return ((phase >> 2) & PS_PHASE_MASK) | trip;
74 }
75 
76 #define SKL_MIN_SRC_W 8
77 #define SKL_MAX_SRC_W 4096
78 #define SKL_MIN_SRC_H 8
79 #define SKL_MAX_SRC_H 4096
80 #define SKL_MIN_DST_W 8
81 #define SKL_MAX_DST_W 4096
82 #define SKL_MIN_DST_H 8
83 #define SKL_MAX_DST_H 4096
84 #define ICL_MAX_SRC_W 5120
85 #define ICL_MAX_SRC_H 4096
86 #define ICL_MAX_DST_W 5120
87 #define ICL_MAX_DST_H 4096
88 #define SKL_MIN_YUV_420_SRC_W 16
89 #define SKL_MIN_YUV_420_SRC_H 16
90 
91 static int
92 skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach,
93 		  unsigned int scaler_user, int *scaler_id,
94 		  int src_w, int src_h, int dst_w, int dst_h,
95 		  const struct drm_format_info *format,
96 		  u64 modifier, bool need_scaler)
97 {
98 	struct intel_crtc_scaler_state *scaler_state =
99 		&crtc_state->scaler_state;
100 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
101 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
102 	const struct drm_display_mode *adjusted_mode =
103 		&crtc_state->hw.adjusted_mode;
104 
105 	/*
106 	 * Src coordinates are already rotated by 270 degrees for
107 	 * the 90/270 degree plane rotation cases (to match the
108 	 * GTT mapping), hence no need to account for rotation here.
109 	 */
110 	if (src_w != dst_w || src_h != dst_h)
111 		need_scaler = true;
112 
113 	/*
114 	 * Scaling/fitting not supported in IF-ID mode in GEN9+
115 	 * TODO: Interlace fetch mode doesn't support YUV420 planar formats.
116 	 * Once NV12 is enabled, handle it here while allocating scaler
117 	 * for NV12.
118 	 */
119 	if (DISPLAY_VER(dev_priv) >= 9 && crtc_state->hw.enable &&
120 	    need_scaler && adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE) {
121 		drm_dbg_kms(&dev_priv->drm,
122 			    "Pipe/Plane scaling not supported with IF-ID mode\n");
123 		return -EINVAL;
124 	}
125 
126 	/*
127 	 * if plane is being disabled or scaler is no more required or force detach
128 	 *  - free scaler binded to this plane/crtc
129 	 *  - in order to do this, update crtc->scaler_usage
130 	 *
131 	 * Here scaler state in crtc_state is set free so that
132 	 * scaler can be assigned to other user. Actual register
133 	 * update to free the scaler is done in plane/panel-fit programming.
134 	 * For this purpose crtc/plane_state->scaler_id isn't reset here.
135 	 */
136 	if (force_detach || !need_scaler) {
137 		if (*scaler_id >= 0) {
138 			scaler_state->scaler_users &= ~(1 << scaler_user);
139 			scaler_state->scalers[*scaler_id].in_use = 0;
140 
141 			drm_dbg_kms(&dev_priv->drm,
142 				    "scaler_user index %u.%u: "
143 				    "Staged freeing scaler id %d scaler_users = 0x%x\n",
144 				    crtc->pipe, scaler_user, *scaler_id,
145 				    scaler_state->scaler_users);
146 			*scaler_id = -1;
147 		}
148 		return 0;
149 	}
150 
151 	if (format && intel_format_info_is_yuv_semiplanar(format, modifier) &&
152 	    (src_h < SKL_MIN_YUV_420_SRC_H || src_w < SKL_MIN_YUV_420_SRC_W)) {
153 		drm_dbg_kms(&dev_priv->drm,
154 			    "Planar YUV: src dimensions not met\n");
155 		return -EINVAL;
156 	}
157 
158 	/* range checks */
159 	if (src_w < SKL_MIN_SRC_W || src_h < SKL_MIN_SRC_H ||
160 	    dst_w < SKL_MIN_DST_W || dst_h < SKL_MIN_DST_H ||
161 	    (DISPLAY_VER(dev_priv) >= 11 &&
162 	     (src_w > ICL_MAX_SRC_W || src_h > ICL_MAX_SRC_H ||
163 	      dst_w > ICL_MAX_DST_W || dst_h > ICL_MAX_DST_H)) ||
164 	    (DISPLAY_VER(dev_priv) < 11 &&
165 	     (src_w > SKL_MAX_SRC_W || src_h > SKL_MAX_SRC_H ||
166 	      dst_w > SKL_MAX_DST_W || dst_h > SKL_MAX_DST_H)))	{
167 		drm_dbg_kms(&dev_priv->drm,
168 			    "scaler_user index %u.%u: src %ux%u dst %ux%u "
169 			    "size is out of scaler range\n",
170 			    crtc->pipe, scaler_user, src_w, src_h,
171 			    dst_w, dst_h);
172 		return -EINVAL;
173 	}
174 
175 	/* mark this plane as a scaler user in crtc_state */
176 	scaler_state->scaler_users |= (1 << scaler_user);
177 	drm_dbg_kms(&dev_priv->drm, "scaler_user index %u.%u: "
178 		    "staged scaling request for %ux%u->%ux%u scaler_users = 0x%x\n",
179 		    crtc->pipe, scaler_user, src_w, src_h, dst_w, dst_h,
180 		    scaler_state->scaler_users);
181 
182 	return 0;
183 }
184 
185 int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state)
186 {
187 	const struct drm_display_mode *pipe_mode = &crtc_state->hw.pipe_mode;
188 	int width, height;
189 
190 	if (crtc_state->pch_pfit.enabled) {
191 		width = drm_rect_width(&crtc_state->pch_pfit.dst);
192 		height = drm_rect_height(&crtc_state->pch_pfit.dst);
193 	} else {
194 		width = pipe_mode->crtc_hdisplay;
195 		height = pipe_mode->crtc_vdisplay;
196 	}
197 	return skl_update_scaler(crtc_state, !crtc_state->hw.active,
198 				 SKL_CRTC_INDEX,
199 				 &crtc_state->scaler_state.scaler_id,
200 				 crtc_state->pipe_src_w, crtc_state->pipe_src_h,
201 				 width, height, NULL, 0,
202 				 crtc_state->pch_pfit.enabled);
203 }
204 
205 /**
206  * skl_update_scaler_plane - Stages update to scaler state for a given plane.
207  * @crtc_state: crtc's scaler state
208  * @plane_state: atomic plane state to update
209  *
210  * Return
211  *     0 - scaler_usage updated successfully
212  *    error - requested scaling cannot be supported or other error condition
213  */
214 int skl_update_scaler_plane(struct intel_crtc_state *crtc_state,
215 			    struct intel_plane_state *plane_state)
216 {
217 	struct intel_plane *intel_plane =
218 		to_intel_plane(plane_state->uapi.plane);
219 	struct drm_i915_private *dev_priv = to_i915(intel_plane->base.dev);
220 	struct drm_framebuffer *fb = plane_state->hw.fb;
221 	int ret;
222 	bool force_detach = !fb || !plane_state->uapi.visible;
223 	bool need_scaler = false;
224 
225 	/* Pre-gen11 and SDR planes always need a scaler for planar formats. */
226 	if (!icl_is_hdr_plane(dev_priv, intel_plane->id) &&
227 	    fb && intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier))
228 		need_scaler = true;
229 
230 	ret = skl_update_scaler(crtc_state, force_detach,
231 				drm_plane_index(&intel_plane->base),
232 				&plane_state->scaler_id,
233 				drm_rect_width(&plane_state->uapi.src) >> 16,
234 				drm_rect_height(&plane_state->uapi.src) >> 16,
235 				drm_rect_width(&plane_state->uapi.dst),
236 				drm_rect_height(&plane_state->uapi.dst),
237 				fb ? fb->format : NULL,
238 				fb ? fb->modifier : 0,
239 				need_scaler);
240 
241 	if (ret || plane_state->scaler_id < 0)
242 		return ret;
243 
244 	/* check colorkey */
245 	if (plane_state->ckey.flags) {
246 		drm_dbg_kms(&dev_priv->drm,
247 			    "[PLANE:%d:%s] scaling with color key not allowed",
248 			    intel_plane->base.base.id,
249 			    intel_plane->base.name);
250 		return -EINVAL;
251 	}
252 
253 	/* Check src format */
254 	switch (fb->format->format) {
255 	case DRM_FORMAT_RGB565:
256 	case DRM_FORMAT_XBGR8888:
257 	case DRM_FORMAT_XRGB8888:
258 	case DRM_FORMAT_ABGR8888:
259 	case DRM_FORMAT_ARGB8888:
260 	case DRM_FORMAT_XRGB2101010:
261 	case DRM_FORMAT_XBGR2101010:
262 	case DRM_FORMAT_ARGB2101010:
263 	case DRM_FORMAT_ABGR2101010:
264 	case DRM_FORMAT_YUYV:
265 	case DRM_FORMAT_YVYU:
266 	case DRM_FORMAT_UYVY:
267 	case DRM_FORMAT_VYUY:
268 	case DRM_FORMAT_NV12:
269 	case DRM_FORMAT_XYUV8888:
270 	case DRM_FORMAT_P010:
271 	case DRM_FORMAT_P012:
272 	case DRM_FORMAT_P016:
273 	case DRM_FORMAT_Y210:
274 	case DRM_FORMAT_Y212:
275 	case DRM_FORMAT_Y216:
276 	case DRM_FORMAT_XVYU2101010:
277 	case DRM_FORMAT_XVYU12_16161616:
278 	case DRM_FORMAT_XVYU16161616:
279 		break;
280 	case DRM_FORMAT_XBGR16161616F:
281 	case DRM_FORMAT_ABGR16161616F:
282 	case DRM_FORMAT_XRGB16161616F:
283 	case DRM_FORMAT_ARGB16161616F:
284 		if (DISPLAY_VER(dev_priv) >= 11)
285 			break;
286 		fallthrough;
287 	default:
288 		drm_dbg_kms(&dev_priv->drm,
289 			    "[PLANE:%d:%s] FB:%d unsupported scaling format 0x%x\n",
290 			    intel_plane->base.base.id, intel_plane->base.name,
291 			    fb->base.id, fb->format->format);
292 		return -EINVAL;
293 	}
294 
295 	return 0;
296 }
297 
298 static int glk_coef_tap(int i)
299 {
300 	return i % 7;
301 }
302 
303 static u16 glk_nearest_filter_coef(int t)
304 {
305 	return t == 3 ? 0x0800 : 0x3000;
306 }
307 
308 /*
309  *  Theory behind setting nearest-neighbor integer scaling:
310  *
311  *  17 phase of 7 taps requires 119 coefficients in 60 dwords per set.
312  *  The letter represents the filter tap (D is the center tap) and the number
313  *  represents the coefficient set for a phase (0-16).
314  *
315  *         +------------+------------------------+------------------------+
316  *         |Index value | Data value coeffient 1 | Data value coeffient 2 |
317  *         +------------+------------------------+------------------------+
318  *         |   00h      |          B0            |          A0            |
319  *         +------------+------------------------+------------------------+
320  *         |   01h      |          D0            |          C0            |
321  *         +------------+------------------------+------------------------+
322  *         |   02h      |          F0            |          E0            |
323  *         +------------+------------------------+------------------------+
324  *         |   03h      |          A1            |          G0            |
325  *         +------------+------------------------+------------------------+
326  *         |   04h      |          C1            |          B1            |
327  *         +------------+------------------------+------------------------+
328  *         |   ...      |          ...           |          ...           |
329  *         +------------+------------------------+------------------------+
330  *         |   38h      |          B16           |          A16           |
331  *         +------------+------------------------+------------------------+
332  *         |   39h      |          D16           |          C16           |
333  *         +------------+------------------------+------------------------+
334  *         |   3Ah      |          F16           |          C16           |
335  *         +------------+------------------------+------------------------+
336  *         |   3Bh      |        Reserved        |          G16           |
337  *         +------------+------------------------+------------------------+
338  *
339  *  To enable nearest-neighbor scaling:  program scaler coefficents with
340  *  the center tap (Dxx) values set to 1 and all other values set to 0 as per
341  *  SCALER_COEFFICIENT_FORMAT
342  *
343  */
344 
345 static void glk_program_nearest_filter_coefs(struct drm_i915_private *dev_priv,
346 					     enum pipe pipe, int id, int set)
347 {
348 	int i;
349 
350 	intel_de_write_fw(dev_priv, GLK_PS_COEF_INDEX_SET(pipe, id, set),
351 			  PS_COEE_INDEX_AUTO_INC);
352 
353 	for (i = 0; i < 17 * 7; i += 2) {
354 		u32 tmp;
355 		int t;
356 
357 		t = glk_coef_tap(i);
358 		tmp = glk_nearest_filter_coef(t);
359 
360 		t = glk_coef_tap(i + 1);
361 		tmp |= glk_nearest_filter_coef(t) << 16;
362 
363 		intel_de_write_fw(dev_priv, GLK_PS_COEF_DATA_SET(pipe, id, set),
364 				  tmp);
365 	}
366 
367 	intel_de_write_fw(dev_priv, GLK_PS_COEF_INDEX_SET(pipe, id, set), 0);
368 }
369 
370 static u32 skl_scaler_get_filter_select(enum drm_scaling_filter filter, int set)
371 {
372 	if (filter == DRM_SCALING_FILTER_NEAREST_NEIGHBOR) {
373 		return (PS_FILTER_PROGRAMMED |
374 			PS_Y_VERT_FILTER_SELECT(set) |
375 			PS_Y_HORZ_FILTER_SELECT(set) |
376 			PS_UV_VERT_FILTER_SELECT(set) |
377 			PS_UV_HORZ_FILTER_SELECT(set));
378 	}
379 
380 	return PS_FILTER_MEDIUM;
381 }
382 
383 static void skl_scaler_setup_filter(struct drm_i915_private *dev_priv, enum pipe pipe,
384 				    int id, int set, enum drm_scaling_filter filter)
385 {
386 	switch (filter) {
387 	case DRM_SCALING_FILTER_DEFAULT:
388 		break;
389 	case DRM_SCALING_FILTER_NEAREST_NEIGHBOR:
390 		glk_program_nearest_filter_coefs(dev_priv, pipe, id, set);
391 		break;
392 	default:
393 		MISSING_CASE(filter);
394 	}
395 }
396 
397 void skl_pfit_enable(const struct intel_crtc_state *crtc_state)
398 {
399 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
400 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
401 	const struct intel_crtc_scaler_state *scaler_state =
402 		&crtc_state->scaler_state;
403 	struct drm_rect src = {
404 		.x2 = crtc_state->pipe_src_w << 16,
405 		.y2 = crtc_state->pipe_src_h << 16,
406 	};
407 	const struct drm_rect *dst = &crtc_state->pch_pfit.dst;
408 	u16 uv_rgb_hphase, uv_rgb_vphase;
409 	enum pipe pipe = crtc->pipe;
410 	int width = drm_rect_width(dst);
411 	int height = drm_rect_height(dst);
412 	int x = dst->x1;
413 	int y = dst->y1;
414 	int hscale, vscale;
415 	unsigned long irqflags;
416 	int id;
417 	u32 ps_ctrl;
418 
419 	if (!crtc_state->pch_pfit.enabled)
420 		return;
421 
422 	if (drm_WARN_ON(&dev_priv->drm,
423 			crtc_state->scaler_state.scaler_id < 0))
424 		return;
425 
426 	hscale = drm_rect_calc_hscale(&src, dst, 0, INT_MAX);
427 	vscale = drm_rect_calc_vscale(&src, dst, 0, INT_MAX);
428 
429 	uv_rgb_hphase = skl_scaler_calc_phase(1, hscale, false);
430 	uv_rgb_vphase = skl_scaler_calc_phase(1, vscale, false);
431 
432 	id = scaler_state->scaler_id;
433 
434 	ps_ctrl = skl_scaler_get_filter_select(crtc_state->hw.scaling_filter, 0);
435 	ps_ctrl |=  PS_SCALER_EN | scaler_state->scalers[id].mode;
436 
437 	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
438 
439 	skl_scaler_setup_filter(dev_priv, pipe, id, 0,
440 				crtc_state->hw.scaling_filter);
441 
442 	intel_de_write_fw(dev_priv, SKL_PS_CTRL(pipe, id), ps_ctrl);
443 
444 	intel_de_write_fw(dev_priv, SKL_PS_VPHASE(pipe, id),
445 			  PS_Y_PHASE(0) | PS_UV_RGB_PHASE(uv_rgb_vphase));
446 	intel_de_write_fw(dev_priv, SKL_PS_HPHASE(pipe, id),
447 			  PS_Y_PHASE(0) | PS_UV_RGB_PHASE(uv_rgb_hphase));
448 	intel_de_write_fw(dev_priv, SKL_PS_WIN_POS(pipe, id),
449 			  x << 16 | y);
450 	intel_de_write_fw(dev_priv, SKL_PS_WIN_SZ(pipe, id),
451 			  width << 16 | height);
452 
453 	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
454 }
455 
456 void
457 skl_program_plane_scaler(struct intel_plane *plane,
458 			 const struct intel_crtc_state *crtc_state,
459 			 const struct intel_plane_state *plane_state)
460 {
461 	struct drm_i915_private *dev_priv = to_i915(plane->base.dev);
462 	const struct drm_framebuffer *fb = plane_state->hw.fb;
463 	enum pipe pipe = plane->pipe;
464 	int scaler_id = plane_state->scaler_id;
465 	const struct intel_scaler *scaler =
466 		&crtc_state->scaler_state.scalers[scaler_id];
467 	int crtc_x = plane_state->uapi.dst.x1;
468 	int crtc_y = plane_state->uapi.dst.y1;
469 	u32 crtc_w = drm_rect_width(&plane_state->uapi.dst);
470 	u32 crtc_h = drm_rect_height(&plane_state->uapi.dst);
471 	u16 y_hphase, uv_rgb_hphase;
472 	u16 y_vphase, uv_rgb_vphase;
473 	int hscale, vscale;
474 	u32 ps_ctrl;
475 
476 	hscale = drm_rect_calc_hscale(&plane_state->uapi.src,
477 				      &plane_state->uapi.dst,
478 				      0, INT_MAX);
479 	vscale = drm_rect_calc_vscale(&plane_state->uapi.src,
480 				      &plane_state->uapi.dst,
481 				      0, INT_MAX);
482 
483 	/* TODO: handle sub-pixel coordinates */
484 	if (intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier) &&
485 	    !icl_is_hdr_plane(dev_priv, plane->id)) {
486 		y_hphase = skl_scaler_calc_phase(1, hscale, false);
487 		y_vphase = skl_scaler_calc_phase(1, vscale, false);
488 
489 		/* MPEG2 chroma siting convention */
490 		uv_rgb_hphase = skl_scaler_calc_phase(2, hscale, true);
491 		uv_rgb_vphase = skl_scaler_calc_phase(2, vscale, false);
492 	} else {
493 		/* not used */
494 		y_hphase = 0;
495 		y_vphase = 0;
496 
497 		uv_rgb_hphase = skl_scaler_calc_phase(1, hscale, false);
498 		uv_rgb_vphase = skl_scaler_calc_phase(1, vscale, false);
499 	}
500 
501 	ps_ctrl = skl_scaler_get_filter_select(plane_state->hw.scaling_filter, 0);
502 	ps_ctrl |= PS_SCALER_EN | PS_PLANE_SEL(plane->id) | scaler->mode;
503 
504 	skl_scaler_setup_filter(dev_priv, pipe, scaler_id, 0,
505 				plane_state->hw.scaling_filter);
506 
507 	intel_de_write_fw(dev_priv, SKL_PS_CTRL(pipe, scaler_id), ps_ctrl);
508 	intel_de_write_fw(dev_priv, SKL_PS_VPHASE(pipe, scaler_id),
509 			  PS_Y_PHASE(y_vphase) | PS_UV_RGB_PHASE(uv_rgb_vphase));
510 	intel_de_write_fw(dev_priv, SKL_PS_HPHASE(pipe, scaler_id),
511 			  PS_Y_PHASE(y_hphase) | PS_UV_RGB_PHASE(uv_rgb_hphase));
512 	intel_de_write_fw(dev_priv, SKL_PS_WIN_POS(pipe, scaler_id),
513 			  (crtc_x << 16) | crtc_y);
514 	intel_de_write_fw(dev_priv, SKL_PS_WIN_SZ(pipe, scaler_id),
515 			  (crtc_w << 16) | crtc_h);
516 }
517 
518 static void skl_detach_scaler(struct intel_crtc *crtc, int id)
519 {
520 	struct drm_device *dev = crtc->base.dev;
521 	struct drm_i915_private *dev_priv = to_i915(dev);
522 	unsigned long irqflags;
523 
524 	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
525 
526 	intel_de_write_fw(dev_priv, SKL_PS_CTRL(crtc->pipe, id), 0);
527 	intel_de_write_fw(dev_priv, SKL_PS_WIN_POS(crtc->pipe, id), 0);
528 	intel_de_write_fw(dev_priv, SKL_PS_WIN_SZ(crtc->pipe, id), 0);
529 
530 	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
531 }
532 
533 /*
534  * This function detaches (aka. unbinds) unused scalers in hardware
535  */
536 void skl_detach_scalers(const struct intel_crtc_state *crtc_state)
537 {
538 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
539 	const struct intel_crtc_scaler_state *scaler_state =
540 		&crtc_state->scaler_state;
541 	int i;
542 
543 	/* loop through and disable scalers that aren't in use */
544 	for (i = 0; i < crtc->num_scalers; i++) {
545 		if (!scaler_state->scalers[i].in_use)
546 			skl_detach_scaler(crtc, i);
547 	}
548 }
549 
550 void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state)
551 {
552 	struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->uapi.crtc);
553 	int i;
554 
555 	for (i = 0; i < crtc->num_scalers; i++)
556 		skl_detach_scaler(crtc, i);
557 }
558