xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_hvs.c (revision 4a948591)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 Broadcom
4  */
5 
6 /**
7  * DOC: VC4 HVS module.
8  *
9  * The Hardware Video Scaler (HVS) is the piece of hardware that does
10  * translation, scaling, colorspace conversion, and compositing of
11  * pixels stored in framebuffers into a FIFO of pixels going out to
12  * the Pixel Valve (CRTC).  It operates at the system clock rate (the
13  * system audio clock gate, specifically), which is much higher than
14  * the pixel clock rate.
15  *
16  * There is a single global HVS, with multiple output FIFOs that can
17  * be consumed by the PVs.  This file just manages the resources for
18  * the HVS, while the vc4_crtc.c code actually drives HVS setup for
19  * each CRTC.
20  */
21 
22 #include <linux/bitfield.h>
23 #include <linux/clk.h>
24 #include <linux/component.h>
25 #include <linux/platform_device.h>
26 
27 #include <drm/drm_atomic_helper.h>
28 #include <drm/drm_drv.h>
29 #include <drm/drm_vblank.h>
30 
31 #include <soc/bcm2835/raspberrypi-firmware.h>
32 
33 #include "vc4_drv.h"
34 #include "vc4_regs.h"
35 
36 static const struct debugfs_reg32 hvs_regs[] = {
37 	VC4_REG32(SCALER_DISPCTRL),
38 	VC4_REG32(SCALER_DISPSTAT),
39 	VC4_REG32(SCALER_DISPID),
40 	VC4_REG32(SCALER_DISPECTRL),
41 	VC4_REG32(SCALER_DISPPROF),
42 	VC4_REG32(SCALER_DISPDITHER),
43 	VC4_REG32(SCALER_DISPEOLN),
44 	VC4_REG32(SCALER_DISPLIST0),
45 	VC4_REG32(SCALER_DISPLIST1),
46 	VC4_REG32(SCALER_DISPLIST2),
47 	VC4_REG32(SCALER_DISPLSTAT),
48 	VC4_REG32(SCALER_DISPLACT0),
49 	VC4_REG32(SCALER_DISPLACT1),
50 	VC4_REG32(SCALER_DISPLACT2),
51 	VC4_REG32(SCALER_DISPCTRL0),
52 	VC4_REG32(SCALER_DISPBKGND0),
53 	VC4_REG32(SCALER_DISPSTAT0),
54 	VC4_REG32(SCALER_DISPBASE0),
55 	VC4_REG32(SCALER_DISPCTRL1),
56 	VC4_REG32(SCALER_DISPBKGND1),
57 	VC4_REG32(SCALER_DISPSTAT1),
58 	VC4_REG32(SCALER_DISPBASE1),
59 	VC4_REG32(SCALER_DISPCTRL2),
60 	VC4_REG32(SCALER_DISPBKGND2),
61 	VC4_REG32(SCALER_DISPSTAT2),
62 	VC4_REG32(SCALER_DISPBASE2),
63 	VC4_REG32(SCALER_DISPALPHA2),
64 	VC4_REG32(SCALER_OLEDOFFS),
65 	VC4_REG32(SCALER_OLEDCOEF0),
66 	VC4_REG32(SCALER_OLEDCOEF1),
67 	VC4_REG32(SCALER_OLEDCOEF2),
68 };
69 
70 void vc4_hvs_dump_state(struct vc4_hvs *hvs)
71 {
72 	struct drm_device *drm = &hvs->vc4->base;
73 	struct drm_printer p = drm_info_printer(&hvs->pdev->dev);
74 	int idx, i;
75 
76 	if (!drm_dev_enter(drm, &idx))
77 		return;
78 
79 	drm_print_regset32(&p, &hvs->regset);
80 
81 	DRM_INFO("HVS ctx:\n");
82 	for (i = 0; i < 64; i += 4) {
83 		DRM_INFO("0x%08x (%s): 0x%08x 0x%08x 0x%08x 0x%08x\n",
84 			 i * 4, i < HVS_BOOTLOADER_DLIST_END ? "B" : "D",
85 			 readl((u32 __iomem *)hvs->dlist + i + 0),
86 			 readl((u32 __iomem *)hvs->dlist + i + 1),
87 			 readl((u32 __iomem *)hvs->dlist + i + 2),
88 			 readl((u32 __iomem *)hvs->dlist + i + 3));
89 	}
90 
91 	drm_dev_exit(idx);
92 }
93 
94 static int vc4_hvs_debugfs_underrun(struct seq_file *m, void *data)
95 {
96 	struct drm_debugfs_entry *entry = m->private;
97 	struct drm_device *dev = entry->dev;
98 	struct vc4_dev *vc4 = to_vc4_dev(dev);
99 	struct drm_printer p = drm_seq_file_printer(m);
100 
101 	drm_printf(&p, "%d\n", atomic_read(&vc4->underrun));
102 
103 	return 0;
104 }
105 
106 static int vc4_hvs_debugfs_dlist(struct seq_file *m, void *data)
107 {
108 	struct drm_debugfs_entry *entry = m->private;
109 	struct drm_device *dev = entry->dev;
110 	struct vc4_dev *vc4 = to_vc4_dev(dev);
111 	struct vc4_hvs *hvs = vc4->hvs;
112 	struct drm_printer p = drm_seq_file_printer(m);
113 	unsigned int dlist_mem_size = hvs->dlist_mem_size;
114 	unsigned int next_entry_start;
115 	unsigned int i, j;
116 	u32 dlist_word, dispstat;
117 
118 	for (i = 0; i < SCALER_CHANNELS_COUNT; i++) {
119 		dispstat = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(i)),
120 					 SCALER_DISPSTATX_MODE);
121 		if (dispstat == SCALER_DISPSTATX_MODE_DISABLED ||
122 		    dispstat == SCALER_DISPSTATX_MODE_EOF) {
123 			drm_printf(&p, "HVS chan %u disabled\n", i);
124 			continue;
125 		}
126 
127 		drm_printf(&p, "HVS chan %u:\n", i);
128 		next_entry_start = 0;
129 
130 		for (j = HVS_READ(SCALER_DISPLISTX(i)); j < dlist_mem_size; j++) {
131 			dlist_word = readl((u32 __iomem *)vc4->hvs->dlist + j);
132 			drm_printf(&p, "dlist: %02d: 0x%08x\n", j,
133 				   dlist_word);
134 			if (!next_entry_start ||
135 			    next_entry_start == j) {
136 				if (dlist_word & SCALER_CTL0_END)
137 					break;
138 				next_entry_start = j +
139 					VC4_GET_FIELD(dlist_word,
140 						      SCALER_CTL0_SIZE);
141 			}
142 		}
143 	}
144 
145 	return 0;
146 }
147 
148 /* The filter kernel is composed of dwords each containing 3 9-bit
149  * signed integers packed next to each other.
150  */
151 #define VC4_INT_TO_COEFF(coeff) (coeff & 0x1ff)
152 #define VC4_PPF_FILTER_WORD(c0, c1, c2)				\
153 	((((c0) & 0x1ff) << 0) |				\
154 	 (((c1) & 0x1ff) << 9) |				\
155 	 (((c2) & 0x1ff) << 18))
156 
157 /* The whole filter kernel is arranged as the coefficients 0-16 going
158  * up, then a pad, then 17-31 going down and reversed within the
159  * dwords.  This means that a linear phase kernel (where it's
160  * symmetrical at the boundary between 15 and 16) has the last 5
161  * dwords matching the first 5, but reversed.
162  */
163 #define VC4_LINEAR_PHASE_KERNEL(c0, c1, c2, c3, c4, c5, c6, c7, c8,	\
164 				c9, c10, c11, c12, c13, c14, c15)	\
165 	{VC4_PPF_FILTER_WORD(c0, c1, c2),				\
166 	 VC4_PPF_FILTER_WORD(c3, c4, c5),				\
167 	 VC4_PPF_FILTER_WORD(c6, c7, c8),				\
168 	 VC4_PPF_FILTER_WORD(c9, c10, c11),				\
169 	 VC4_PPF_FILTER_WORD(c12, c13, c14),				\
170 	 VC4_PPF_FILTER_WORD(c15, c15, 0)}
171 
172 #define VC4_LINEAR_PHASE_KERNEL_DWORDS 6
173 #define VC4_KERNEL_DWORDS (VC4_LINEAR_PHASE_KERNEL_DWORDS * 2 - 1)
174 
175 /* Recommended B=1/3, C=1/3 filter choice from Mitchell/Netravali.
176  * http://www.cs.utexas.edu/~fussell/courses/cs384g/lectures/mitchell/Mitchell.pdf
177  */
178 static const u32 mitchell_netravali_1_3_1_3_kernel[] =
179 	VC4_LINEAR_PHASE_KERNEL(0, -2, -6, -8, -10, -8, -3, 2, 18,
180 				50, 82, 119, 155, 187, 213, 227);
181 
182 static int vc4_hvs_upload_linear_kernel(struct vc4_hvs *hvs,
183 					struct drm_mm_node *space,
184 					const u32 *kernel)
185 {
186 	int ret, i;
187 	u32 __iomem *dst_kernel;
188 
189 	/*
190 	 * NOTE: We don't need a call to drm_dev_enter()/drm_dev_exit()
191 	 * here since that function is only called from vc4_hvs_bind().
192 	 */
193 
194 	ret = drm_mm_insert_node(&hvs->dlist_mm, space, VC4_KERNEL_DWORDS);
195 	if (ret) {
196 		DRM_ERROR("Failed to allocate space for filter kernel: %d\n",
197 			  ret);
198 		return ret;
199 	}
200 
201 	dst_kernel = hvs->dlist + space->start;
202 
203 	for (i = 0; i < VC4_KERNEL_DWORDS; i++) {
204 		if (i < VC4_LINEAR_PHASE_KERNEL_DWORDS)
205 			writel(kernel[i], &dst_kernel[i]);
206 		else {
207 			writel(kernel[VC4_KERNEL_DWORDS - i - 1],
208 			       &dst_kernel[i]);
209 		}
210 	}
211 
212 	return 0;
213 }
214 
215 static void vc4_hvs_lut_load(struct vc4_hvs *hvs,
216 			     struct vc4_crtc *vc4_crtc)
217 {
218 	struct drm_device *drm = &hvs->vc4->base;
219 	struct drm_crtc *crtc = &vc4_crtc->base;
220 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
221 	int idx;
222 	u32 i;
223 
224 	if (!drm_dev_enter(drm, &idx))
225 		return;
226 
227 	if (hvs->vc4->is_vc5)
228 		return;
229 
230 	/* The LUT memory is laid out with each HVS channel in order,
231 	 * each of which takes 256 writes for R, 256 for G, then 256
232 	 * for B.
233 	 */
234 	HVS_WRITE(SCALER_GAMADDR,
235 		  SCALER_GAMADDR_AUTOINC |
236 		  (vc4_state->assigned_channel * 3 * crtc->gamma_size));
237 
238 	for (i = 0; i < crtc->gamma_size; i++)
239 		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_r[i]);
240 	for (i = 0; i < crtc->gamma_size; i++)
241 		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_g[i]);
242 	for (i = 0; i < crtc->gamma_size; i++)
243 		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_b[i]);
244 
245 	drm_dev_exit(idx);
246 }
247 
248 static void vc4_hvs_update_gamma_lut(struct vc4_hvs *hvs,
249 				     struct vc4_crtc *vc4_crtc)
250 {
251 	struct drm_crtc_state *crtc_state = vc4_crtc->base.state;
252 	struct drm_color_lut *lut = crtc_state->gamma_lut->data;
253 	u32 length = drm_color_lut_size(crtc_state->gamma_lut);
254 	u32 i;
255 
256 	for (i = 0; i < length; i++) {
257 		vc4_crtc->lut_r[i] = drm_color_lut_extract(lut[i].red, 8);
258 		vc4_crtc->lut_g[i] = drm_color_lut_extract(lut[i].green, 8);
259 		vc4_crtc->lut_b[i] = drm_color_lut_extract(lut[i].blue, 8);
260 	}
261 
262 	vc4_hvs_lut_load(hvs, vc4_crtc);
263 }
264 
265 u8 vc4_hvs_get_fifo_frame_count(struct vc4_hvs *hvs, unsigned int fifo)
266 {
267 	struct drm_device *drm = &hvs->vc4->base;
268 	u8 field = 0;
269 	int idx;
270 
271 	if (!drm_dev_enter(drm, &idx))
272 		return 0;
273 
274 	switch (fifo) {
275 	case 0:
276 		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
277 				      SCALER_DISPSTAT1_FRCNT0);
278 		break;
279 	case 1:
280 		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
281 				      SCALER_DISPSTAT1_FRCNT1);
282 		break;
283 	case 2:
284 		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT2),
285 				      SCALER_DISPSTAT2_FRCNT2);
286 		break;
287 	}
288 
289 	drm_dev_exit(idx);
290 	return field;
291 }
292 
293 int vc4_hvs_get_fifo_from_output(struct vc4_hvs *hvs, unsigned int output)
294 {
295 	struct vc4_dev *vc4 = hvs->vc4;
296 	u32 reg;
297 	int ret;
298 
299 	if (!vc4->is_vc5)
300 		return output;
301 
302 	/*
303 	 * NOTE: We should probably use drm_dev_enter()/drm_dev_exit()
304 	 * here, but this function is only used during the DRM device
305 	 * initialization, so we should be fine.
306 	 */
307 
308 	switch (output) {
309 	case 0:
310 		return 0;
311 
312 	case 1:
313 		return 1;
314 
315 	case 2:
316 		reg = HVS_READ(SCALER_DISPECTRL);
317 		ret = FIELD_GET(SCALER_DISPECTRL_DSP2_MUX_MASK, reg);
318 		if (ret == 0)
319 			return 2;
320 
321 		return 0;
322 
323 	case 3:
324 		reg = HVS_READ(SCALER_DISPCTRL);
325 		ret = FIELD_GET(SCALER_DISPCTRL_DSP3_MUX_MASK, reg);
326 		if (ret == 3)
327 			return -EPIPE;
328 
329 		return ret;
330 
331 	case 4:
332 		reg = HVS_READ(SCALER_DISPEOLN);
333 		ret = FIELD_GET(SCALER_DISPEOLN_DSP4_MUX_MASK, reg);
334 		if (ret == 3)
335 			return -EPIPE;
336 
337 		return ret;
338 
339 	case 5:
340 		reg = HVS_READ(SCALER_DISPDITHER);
341 		ret = FIELD_GET(SCALER_DISPDITHER_DSP5_MUX_MASK, reg);
342 		if (ret == 3)
343 			return -EPIPE;
344 
345 		return ret;
346 
347 	default:
348 		return -EPIPE;
349 	}
350 }
351 
352 static int vc4_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
353 				struct drm_display_mode *mode, bool oneshot)
354 {
355 	struct vc4_dev *vc4 = hvs->vc4;
356 	struct drm_device *drm = &vc4->base;
357 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
358 	struct vc4_crtc_state *vc4_crtc_state = to_vc4_crtc_state(crtc->state);
359 	unsigned int chan = vc4_crtc_state->assigned_channel;
360 	bool interlace = mode->flags & DRM_MODE_FLAG_INTERLACE;
361 	u32 dispbkgndx;
362 	u32 dispctrl;
363 	int idx;
364 
365 	if (!drm_dev_enter(drm, &idx))
366 		return -ENODEV;
367 
368 	HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
369 	HVS_WRITE(SCALER_DISPCTRLX(chan), SCALER_DISPCTRLX_RESET);
370 	HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
371 
372 	/* Turn on the scaler, which will wait for vstart to start
373 	 * compositing.
374 	 * When feeding the transposer, we should operate in oneshot
375 	 * mode.
376 	 */
377 	dispctrl = SCALER_DISPCTRLX_ENABLE;
378 	dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(chan));
379 
380 	if (!vc4->is_vc5) {
381 		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
382 					  SCALER_DISPCTRLX_WIDTH) |
383 			    VC4_SET_FIELD(mode->vdisplay,
384 					  SCALER_DISPCTRLX_HEIGHT) |
385 			    (oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
386 		dispbkgndx |= SCALER_DISPBKGND_AUTOHS;
387 	} else {
388 		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
389 					  SCALER5_DISPCTRLX_WIDTH) |
390 			    VC4_SET_FIELD(mode->vdisplay,
391 					  SCALER5_DISPCTRLX_HEIGHT) |
392 			    (oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
393 		dispbkgndx &= ~SCALER5_DISPBKGND_BCK2BCK;
394 	}
395 
396 	HVS_WRITE(SCALER_DISPCTRLX(chan), dispctrl);
397 
398 	dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
399 	dispbkgndx &= ~SCALER_DISPBKGND_INTERLACE;
400 
401 	HVS_WRITE(SCALER_DISPBKGNDX(chan), dispbkgndx |
402 		  ((!vc4->is_vc5) ? SCALER_DISPBKGND_GAMMA : 0) |
403 		  (interlace ? SCALER_DISPBKGND_INTERLACE : 0));
404 
405 	/* Reload the LUT, since the SRAMs would have been disabled if
406 	 * all CRTCs had SCALER_DISPBKGND_GAMMA unset at once.
407 	 */
408 	vc4_hvs_lut_load(hvs, vc4_crtc);
409 
410 	drm_dev_exit(idx);
411 
412 	return 0;
413 }
414 
415 void vc4_hvs_stop_channel(struct vc4_hvs *hvs, unsigned int chan)
416 {
417 	struct drm_device *drm = &hvs->vc4->base;
418 	int idx;
419 
420 	if (!drm_dev_enter(drm, &idx))
421 		return;
422 
423 	if (!(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_ENABLE))
424 		goto out;
425 
426 	HVS_WRITE(SCALER_DISPCTRLX(chan), SCALER_DISPCTRLX_RESET);
427 	HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
428 
429 	/* Once we leave, the scaler should be disabled and its fifo empty. */
430 	WARN_ON_ONCE(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_RESET);
431 
432 	WARN_ON_ONCE(VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(chan)),
433 				   SCALER_DISPSTATX_MODE) !=
434 		     SCALER_DISPSTATX_MODE_DISABLED);
435 
436 	WARN_ON_ONCE((HVS_READ(SCALER_DISPSTATX(chan)) &
437 		      (SCALER_DISPSTATX_FULL | SCALER_DISPSTATX_EMPTY)) !=
438 		     SCALER_DISPSTATX_EMPTY);
439 
440 out:
441 	drm_dev_exit(idx);
442 }
443 
444 int vc4_hvs_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
445 {
446 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
447 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc_state);
448 	struct drm_device *dev = crtc->dev;
449 	struct vc4_dev *vc4 = to_vc4_dev(dev);
450 	struct drm_plane *plane;
451 	unsigned long flags;
452 	const struct drm_plane_state *plane_state;
453 	u32 dlist_count = 0;
454 	int ret;
455 
456 	/* The pixelvalve can only feed one encoder (and encoders are
457 	 * 1:1 with connectors.)
458 	 */
459 	if (hweight32(crtc_state->connector_mask) > 1)
460 		return -EINVAL;
461 
462 	drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state)
463 		dlist_count += vc4_plane_dlist_size(plane_state);
464 
465 	dlist_count++; /* Account for SCALER_CTL0_END. */
466 
467 	spin_lock_irqsave(&vc4->hvs->mm_lock, flags);
468 	ret = drm_mm_insert_node(&vc4->hvs->dlist_mm, &vc4_state->mm,
469 				 dlist_count);
470 	spin_unlock_irqrestore(&vc4->hvs->mm_lock, flags);
471 	if (ret)
472 		return ret;
473 
474 	return 0;
475 }
476 
477 static void vc4_hvs_install_dlist(struct drm_crtc *crtc)
478 {
479 	struct drm_device *dev = crtc->dev;
480 	struct vc4_dev *vc4 = to_vc4_dev(dev);
481 	struct vc4_hvs *hvs = vc4->hvs;
482 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
483 	int idx;
484 
485 	if (!drm_dev_enter(dev, &idx))
486 		return;
487 
488 	HVS_WRITE(SCALER_DISPLISTX(vc4_state->assigned_channel),
489 		  vc4_state->mm.start);
490 
491 	drm_dev_exit(idx);
492 }
493 
494 static void vc4_hvs_update_dlist(struct drm_crtc *crtc)
495 {
496 	struct drm_device *dev = crtc->dev;
497 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
498 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
499 	unsigned long flags;
500 
501 	if (crtc->state->event) {
502 		crtc->state->event->pipe = drm_crtc_index(crtc);
503 
504 		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
505 
506 		spin_lock_irqsave(&dev->event_lock, flags);
507 
508 		if (!vc4_crtc->feeds_txp || vc4_state->txp_armed) {
509 			vc4_crtc->event = crtc->state->event;
510 			crtc->state->event = NULL;
511 		}
512 
513 		spin_unlock_irqrestore(&dev->event_lock, flags);
514 	}
515 
516 	spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
517 	vc4_crtc->current_dlist = vc4_state->mm.start;
518 	spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
519 }
520 
521 void vc4_hvs_atomic_begin(struct drm_crtc *crtc,
522 			  struct drm_atomic_state *state)
523 {
524 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
525 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
526 	unsigned long flags;
527 
528 	spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
529 	vc4_crtc->current_hvs_channel = vc4_state->assigned_channel;
530 	spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
531 }
532 
533 void vc4_hvs_atomic_enable(struct drm_crtc *crtc,
534 			   struct drm_atomic_state *state)
535 {
536 	struct drm_device *dev = crtc->dev;
537 	struct vc4_dev *vc4 = to_vc4_dev(dev);
538 	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
539 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
540 	bool oneshot = vc4_crtc->feeds_txp;
541 
542 	vc4_hvs_install_dlist(crtc);
543 	vc4_hvs_update_dlist(crtc);
544 	vc4_hvs_init_channel(vc4->hvs, crtc, mode, oneshot);
545 }
546 
547 void vc4_hvs_atomic_disable(struct drm_crtc *crtc,
548 			    struct drm_atomic_state *state)
549 {
550 	struct drm_device *dev = crtc->dev;
551 	struct vc4_dev *vc4 = to_vc4_dev(dev);
552 	struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state, crtc);
553 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(old_state);
554 	unsigned int chan = vc4_state->assigned_channel;
555 
556 	vc4_hvs_stop_channel(vc4->hvs, chan);
557 }
558 
559 void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
560 			  struct drm_atomic_state *state)
561 {
562 	struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state,
563 									 crtc);
564 	struct drm_device *dev = crtc->dev;
565 	struct vc4_dev *vc4 = to_vc4_dev(dev);
566 	struct vc4_hvs *hvs = vc4->hvs;
567 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
568 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
569 	unsigned int channel = vc4_state->assigned_channel;
570 	struct drm_plane *plane;
571 	struct vc4_plane_state *vc4_plane_state;
572 	bool debug_dump_regs = false;
573 	bool enable_bg_fill = false;
574 	u32 __iomem *dlist_start = vc4->hvs->dlist + vc4_state->mm.start;
575 	u32 __iomem *dlist_next = dlist_start;
576 	unsigned int zpos = 0;
577 	bool found = false;
578 	int idx;
579 
580 	if (!drm_dev_enter(dev, &idx)) {
581 		vc4_crtc_send_vblank(crtc);
582 		return;
583 	}
584 
585 	if (vc4_state->assigned_channel == VC4_HVS_CHANNEL_DISABLED)
586 		goto exit;
587 
588 	if (debug_dump_regs) {
589 		DRM_INFO("CRTC %d HVS before:\n", drm_crtc_index(crtc));
590 		vc4_hvs_dump_state(hvs);
591 	}
592 
593 	/* Copy all the active planes' dlist contents to the hardware dlist. */
594 	do {
595 		found = false;
596 
597 		drm_atomic_crtc_for_each_plane(plane, crtc) {
598 			if (plane->state->normalized_zpos != zpos)
599 				continue;
600 
601 			/* Is this the first active plane? */
602 			if (dlist_next == dlist_start) {
603 				/* We need to enable background fill when a plane
604 				 * could be alpha blending from the background, i.e.
605 				 * where no other plane is underneath. It suffices to
606 				 * consider the first active plane here since we set
607 				 * needs_bg_fill such that either the first plane
608 				 * already needs it or all planes on top blend from
609 				 * the first or a lower plane.
610 				 */
611 				vc4_plane_state = to_vc4_plane_state(plane->state);
612 				enable_bg_fill = vc4_plane_state->needs_bg_fill;
613 			}
614 
615 			dlist_next += vc4_plane_write_dlist(plane, dlist_next);
616 
617 			found = true;
618 		}
619 
620 		zpos++;
621 	} while (found);
622 
623 	writel(SCALER_CTL0_END, dlist_next);
624 	dlist_next++;
625 
626 	WARN_ON_ONCE(dlist_next - dlist_start != vc4_state->mm.size);
627 
628 	if (enable_bg_fill)
629 		/* This sets a black background color fill, as is the case
630 		 * with other DRM drivers.
631 		 */
632 		HVS_WRITE(SCALER_DISPBKGNDX(channel),
633 			  HVS_READ(SCALER_DISPBKGNDX(channel)) |
634 			  SCALER_DISPBKGND_FILL);
635 
636 	/* Only update DISPLIST if the CRTC was already running and is not
637 	 * being disabled.
638 	 * vc4_crtc_enable() takes care of updating the dlist just after
639 	 * re-enabling VBLANK interrupts and before enabling the engine.
640 	 * If the CRTC is being disabled, there's no point in updating this
641 	 * information.
642 	 */
643 	if (crtc->state->active && old_state->active) {
644 		vc4_hvs_install_dlist(crtc);
645 		vc4_hvs_update_dlist(crtc);
646 	}
647 
648 	if (crtc->state->color_mgmt_changed) {
649 		u32 dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(channel));
650 
651 		if (crtc->state->gamma_lut) {
652 			vc4_hvs_update_gamma_lut(hvs, vc4_crtc);
653 			dispbkgndx |= SCALER_DISPBKGND_GAMMA;
654 		} else {
655 			/* Unsetting DISPBKGND_GAMMA skips the gamma lut step
656 			 * in hardware, which is the same as a linear lut that
657 			 * DRM expects us to use in absence of a user lut.
658 			 */
659 			dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
660 		}
661 		HVS_WRITE(SCALER_DISPBKGNDX(channel), dispbkgndx);
662 	}
663 
664 	if (debug_dump_regs) {
665 		DRM_INFO("CRTC %d HVS after:\n", drm_crtc_index(crtc));
666 		vc4_hvs_dump_state(hvs);
667 	}
668 
669 exit:
670 	drm_dev_exit(idx);
671 }
672 
673 void vc4_hvs_mask_underrun(struct vc4_hvs *hvs, int channel)
674 {
675 	struct drm_device *drm = &hvs->vc4->base;
676 	u32 dispctrl;
677 	int idx;
678 
679 	if (!drm_dev_enter(drm, &idx))
680 		return;
681 
682 	dispctrl = HVS_READ(SCALER_DISPCTRL);
683 	dispctrl &= ~(hvs->vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
684 					 SCALER_DISPCTRL_DSPEISLUR(channel));
685 
686 	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
687 
688 	drm_dev_exit(idx);
689 }
690 
691 void vc4_hvs_unmask_underrun(struct vc4_hvs *hvs, int channel)
692 {
693 	struct drm_device *drm = &hvs->vc4->base;
694 	u32 dispctrl;
695 	int idx;
696 
697 	if (!drm_dev_enter(drm, &idx))
698 		return;
699 
700 	dispctrl = HVS_READ(SCALER_DISPCTRL);
701 	dispctrl |= (hvs->vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
702 					SCALER_DISPCTRL_DSPEISLUR(channel));
703 
704 	HVS_WRITE(SCALER_DISPSTAT,
705 		  SCALER_DISPSTAT_EUFLOW(channel));
706 	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
707 
708 	drm_dev_exit(idx);
709 }
710 
711 static void vc4_hvs_report_underrun(struct drm_device *dev)
712 {
713 	struct vc4_dev *vc4 = to_vc4_dev(dev);
714 
715 	atomic_inc(&vc4->underrun);
716 	DRM_DEV_ERROR(dev->dev, "HVS underrun\n");
717 }
718 
719 static irqreturn_t vc4_hvs_irq_handler(int irq, void *data)
720 {
721 	struct drm_device *dev = data;
722 	struct vc4_dev *vc4 = to_vc4_dev(dev);
723 	struct vc4_hvs *hvs = vc4->hvs;
724 	irqreturn_t irqret = IRQ_NONE;
725 	int channel;
726 	u32 control;
727 	u32 status;
728 	u32 dspeislur;
729 
730 	/*
731 	 * NOTE: We don't need to protect the register access using
732 	 * drm_dev_enter() there because the interrupt handler lifetime
733 	 * is tied to the device itself, and not to the DRM device.
734 	 *
735 	 * So when the device will be gone, one of the first thing we
736 	 * will be doing will be to unregister the interrupt handler,
737 	 * and then unregister the DRM device. drm_dev_enter() would
738 	 * thus always succeed if we are here.
739 	 */
740 
741 	status = HVS_READ(SCALER_DISPSTAT);
742 	control = HVS_READ(SCALER_DISPCTRL);
743 
744 	for (channel = 0; channel < SCALER_CHANNELS_COUNT; channel++) {
745 		dspeislur = vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
746 					  SCALER_DISPCTRL_DSPEISLUR(channel);
747 		/* Interrupt masking is not always honored, so check it here. */
748 		if (status & SCALER_DISPSTAT_EUFLOW(channel) &&
749 		    control & dspeislur) {
750 			vc4_hvs_mask_underrun(hvs, channel);
751 			vc4_hvs_report_underrun(dev);
752 
753 			irqret = IRQ_HANDLED;
754 		}
755 	}
756 
757 	/* Clear every per-channel interrupt flag. */
758 	HVS_WRITE(SCALER_DISPSTAT, SCALER_DISPSTAT_IRQMASK(0) |
759 				   SCALER_DISPSTAT_IRQMASK(1) |
760 				   SCALER_DISPSTAT_IRQMASK(2));
761 
762 	return irqret;
763 }
764 
765 int vc4_hvs_debugfs_init(struct drm_minor *minor)
766 {
767 	struct drm_device *drm = minor->dev;
768 	struct vc4_dev *vc4 = to_vc4_dev(drm);
769 	struct vc4_hvs *hvs = vc4->hvs;
770 
771 	if (!vc4->hvs)
772 		return -ENODEV;
773 
774 	if (!vc4->is_vc5)
775 		debugfs_create_bool("hvs_load_tracker", S_IRUGO | S_IWUSR,
776 				    minor->debugfs_root,
777 				    &vc4->load_tracker_enabled);
778 
779 	drm_debugfs_add_file(drm, "hvs_dlists", vc4_hvs_debugfs_dlist, NULL);
780 
781 	drm_debugfs_add_file(drm, "hvs_underrun", vc4_hvs_debugfs_underrun, NULL);
782 
783 	vc4_debugfs_add_regset32(drm, "hvs_regs", &hvs->regset);
784 
785 	return 0;
786 }
787 
788 struct vc4_hvs *__vc4_hvs_alloc(struct vc4_dev *vc4, struct platform_device *pdev)
789 {
790 	struct drm_device *drm = &vc4->base;
791 	struct vc4_hvs *hvs;
792 
793 	hvs = drmm_kzalloc(drm, sizeof(*hvs), GFP_KERNEL);
794 	if (!hvs)
795 		return ERR_PTR(-ENOMEM);
796 
797 	hvs->vc4 = vc4;
798 	hvs->pdev = pdev;
799 
800 	spin_lock_init(&hvs->mm_lock);
801 
802 	/* Set up the HVS display list memory manager.  We never
803 	 * overwrite the setup from the bootloader (just 128b out of
804 	 * our 16K), since we don't want to scramble the screen when
805 	 * transitioning from the firmware's boot setup to runtime.
806 	 */
807 	hvs->dlist_mem_size = (SCALER_DLIST_SIZE >> 2) - HVS_BOOTLOADER_DLIST_END;
808 	drm_mm_init(&hvs->dlist_mm,
809 		    HVS_BOOTLOADER_DLIST_END,
810 		    hvs->dlist_mem_size);
811 
812 	/* Set up the HVS LBM memory manager.  We could have some more
813 	 * complicated data structure that allowed reuse of LBM areas
814 	 * between planes when they don't overlap on the screen, but
815 	 * for now we just allocate globally.
816 	 */
817 	if (!vc4->is_vc5)
818 		/* 48k words of 2x12-bit pixels */
819 		drm_mm_init(&hvs->lbm_mm, 0, 48 * 1024);
820 	else
821 		/* 60k words of 4x12-bit pixels */
822 		drm_mm_init(&hvs->lbm_mm, 0, 60 * 1024);
823 
824 	vc4->hvs = hvs;
825 
826 	return hvs;
827 }
828 
829 static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
830 {
831 	struct platform_device *pdev = to_platform_device(dev);
832 	struct drm_device *drm = dev_get_drvdata(master);
833 	struct vc4_dev *vc4 = to_vc4_dev(drm);
834 	struct vc4_hvs *hvs = NULL;
835 	int ret;
836 	u32 dispctrl;
837 	u32 reg, top;
838 
839 	hvs = __vc4_hvs_alloc(vc4, NULL);
840 	if (IS_ERR(hvs))
841 		return PTR_ERR(hvs);
842 
843 	hvs->regs = vc4_ioremap_regs(pdev, 0);
844 	if (IS_ERR(hvs->regs))
845 		return PTR_ERR(hvs->regs);
846 
847 	hvs->regset.base = hvs->regs;
848 	hvs->regset.regs = hvs_regs;
849 	hvs->regset.nregs = ARRAY_SIZE(hvs_regs);
850 
851 	if (vc4->is_vc5) {
852 		struct rpi_firmware *firmware;
853 		struct device_node *node;
854 		unsigned int max_rate;
855 
856 		node = rpi_firmware_find_node();
857 		if (!node)
858 			return -EINVAL;
859 
860 		firmware = rpi_firmware_get(node);
861 		of_node_put(node);
862 		if (!firmware)
863 			return -EPROBE_DEFER;
864 
865 		hvs->core_clk = devm_clk_get(&pdev->dev, NULL);
866 		if (IS_ERR(hvs->core_clk)) {
867 			dev_err(&pdev->dev, "Couldn't get core clock\n");
868 			return PTR_ERR(hvs->core_clk);
869 		}
870 
871 		max_rate = rpi_firmware_clk_get_max_rate(firmware,
872 							 RPI_FIRMWARE_CORE_CLK_ID);
873 		rpi_firmware_put(firmware);
874 		if (max_rate >= 550000000)
875 			hvs->vc5_hdmi_enable_hdmi_20 = true;
876 
877 		if (max_rate >= 600000000)
878 			hvs->vc5_hdmi_enable_4096by2160 = true;
879 
880 		hvs->max_core_rate = max_rate;
881 
882 		ret = clk_prepare_enable(hvs->core_clk);
883 		if (ret) {
884 			dev_err(&pdev->dev, "Couldn't enable the core clock\n");
885 			return ret;
886 		}
887 	}
888 
889 	if (!vc4->is_vc5)
890 		hvs->dlist = hvs->regs + SCALER_DLIST_START;
891 	else
892 		hvs->dlist = hvs->regs + SCALER5_DLIST_START;
893 
894 	/* Upload filter kernels.  We only have the one for now, so we
895 	 * keep it around for the lifetime of the driver.
896 	 */
897 	ret = vc4_hvs_upload_linear_kernel(hvs,
898 					   &hvs->mitchell_netravali_filter,
899 					   mitchell_netravali_1_3_1_3_kernel);
900 	if (ret)
901 		return ret;
902 
903 	reg = HVS_READ(SCALER_DISPECTRL);
904 	reg &= ~SCALER_DISPECTRL_DSP2_MUX_MASK;
905 	HVS_WRITE(SCALER_DISPECTRL,
906 		  reg | VC4_SET_FIELD(0, SCALER_DISPECTRL_DSP2_MUX));
907 
908 	reg = HVS_READ(SCALER_DISPCTRL);
909 	reg &= ~SCALER_DISPCTRL_DSP3_MUX_MASK;
910 	HVS_WRITE(SCALER_DISPCTRL,
911 		  reg | VC4_SET_FIELD(3, SCALER_DISPCTRL_DSP3_MUX));
912 
913 	reg = HVS_READ(SCALER_DISPEOLN);
914 	reg &= ~SCALER_DISPEOLN_DSP4_MUX_MASK;
915 	HVS_WRITE(SCALER_DISPEOLN,
916 		  reg | VC4_SET_FIELD(3, SCALER_DISPEOLN_DSP4_MUX));
917 
918 	reg = HVS_READ(SCALER_DISPDITHER);
919 	reg &= ~SCALER_DISPDITHER_DSP5_MUX_MASK;
920 	HVS_WRITE(SCALER_DISPDITHER,
921 		  reg | VC4_SET_FIELD(3, SCALER_DISPDITHER_DSP5_MUX));
922 
923 	dispctrl = HVS_READ(SCALER_DISPCTRL);
924 
925 	dispctrl |= SCALER_DISPCTRL_ENABLE;
926 	dispctrl |= SCALER_DISPCTRL_DISPEIRQ(0) |
927 		    SCALER_DISPCTRL_DISPEIRQ(1) |
928 		    SCALER_DISPCTRL_DISPEIRQ(2);
929 
930 	if (!vc4->is_vc5)
931 		dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
932 			      SCALER_DISPCTRL_SLVWREIRQ |
933 			      SCALER_DISPCTRL_SLVRDEIRQ |
934 			      SCALER_DISPCTRL_DSPEIEOF(0) |
935 			      SCALER_DISPCTRL_DSPEIEOF(1) |
936 			      SCALER_DISPCTRL_DSPEIEOF(2) |
937 			      SCALER_DISPCTRL_DSPEIEOLN(0) |
938 			      SCALER_DISPCTRL_DSPEIEOLN(1) |
939 			      SCALER_DISPCTRL_DSPEIEOLN(2) |
940 			      SCALER_DISPCTRL_DSPEISLUR(0) |
941 			      SCALER_DISPCTRL_DSPEISLUR(1) |
942 			      SCALER_DISPCTRL_DSPEISLUR(2) |
943 			      SCALER_DISPCTRL_SCLEIRQ);
944 	else
945 		dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
946 			      SCALER5_DISPCTRL_SLVEIRQ |
947 			      SCALER5_DISPCTRL_DSPEIEOF(0) |
948 			      SCALER5_DISPCTRL_DSPEIEOF(1) |
949 			      SCALER5_DISPCTRL_DSPEIEOF(2) |
950 			      SCALER5_DISPCTRL_DSPEIEOLN(0) |
951 			      SCALER5_DISPCTRL_DSPEIEOLN(1) |
952 			      SCALER5_DISPCTRL_DSPEIEOLN(2) |
953 			      SCALER5_DISPCTRL_DSPEISLUR(0) |
954 			      SCALER5_DISPCTRL_DSPEISLUR(1) |
955 			      SCALER5_DISPCTRL_DSPEISLUR(2) |
956 			      SCALER_DISPCTRL_SCLEIRQ);
957 
958 
959 	/* Set AXI panic mode.
960 	 * VC4 panics when < 2 lines in FIFO.
961 	 * VC5 panics when less than 1 line in the FIFO.
962 	 */
963 	dispctrl &= ~(SCALER_DISPCTRL_PANIC0_MASK |
964 		      SCALER_DISPCTRL_PANIC1_MASK |
965 		      SCALER_DISPCTRL_PANIC2_MASK);
966 	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC0);
967 	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC1);
968 	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC2);
969 
970 	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
971 
972 	/* Recompute Composite Output Buffer (COB) allocations for the displays
973 	 */
974 	if (!vc4->is_vc5) {
975 		/* The COB is 20736 pixels, or just over 10 lines at 2048 wide.
976 		 * The bottom 2048 pixels are full 32bpp RGBA (intended for the
977 		 * TXP composing RGBA to memory), whilst the remainder are only
978 		 * 24bpp RGB.
979 		 *
980 		 * Assign 3 lines to channels 1 & 2, and just over 4 lines to
981 		 * channel 0.
982 		 */
983 		#define VC4_COB_SIZE		20736
984 		#define VC4_COB_LINE_WIDTH	2048
985 		#define VC4_COB_NUM_LINES	3
986 		reg = 0;
987 		top = VC4_COB_LINE_WIDTH * VC4_COB_NUM_LINES;
988 		reg |= (top - 1) << 16;
989 		HVS_WRITE(SCALER_DISPBASE2, reg);
990 		reg = top;
991 		top += VC4_COB_LINE_WIDTH * VC4_COB_NUM_LINES;
992 		reg |= (top - 1) << 16;
993 		HVS_WRITE(SCALER_DISPBASE1, reg);
994 		reg = top;
995 		top = VC4_COB_SIZE;
996 		reg |= (top - 1) << 16;
997 		HVS_WRITE(SCALER_DISPBASE0, reg);
998 	} else {
999 		/* The COB is 44416 pixels, or 10.8 lines at 4096 wide.
1000 		 * The bottom 4096 pixels are full RGBA (intended for the TXP
1001 		 * composing RGBA to memory), whilst the remainder are only
1002 		 * RGB. Addressing is always pixel wide.
1003 		 *
1004 		 * Assign 3 lines of 4096 to channels 1 & 2, and just over 4
1005 		 * lines. to channel 0.
1006 		 */
1007 		#define VC5_COB_SIZE		44416
1008 		#define VC5_COB_LINE_WIDTH	4096
1009 		#define VC5_COB_NUM_LINES	3
1010 		reg = 0;
1011 		top = VC5_COB_LINE_WIDTH * VC5_COB_NUM_LINES;
1012 		reg |= top << 16;
1013 		HVS_WRITE(SCALER_DISPBASE2, reg);
1014 		top += 16;
1015 		reg = top;
1016 		top += VC5_COB_LINE_WIDTH * VC5_COB_NUM_LINES;
1017 		reg |= top << 16;
1018 		HVS_WRITE(SCALER_DISPBASE1, reg);
1019 		top += 16;
1020 		reg = top;
1021 		top = VC5_COB_SIZE;
1022 		reg |= top << 16;
1023 		HVS_WRITE(SCALER_DISPBASE0, reg);
1024 	}
1025 
1026 	ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
1027 			       vc4_hvs_irq_handler, 0, "vc4 hvs", drm);
1028 	if (ret)
1029 		return ret;
1030 
1031 	return 0;
1032 }
1033 
1034 static void vc4_hvs_unbind(struct device *dev, struct device *master,
1035 			   void *data)
1036 {
1037 	struct drm_device *drm = dev_get_drvdata(master);
1038 	struct vc4_dev *vc4 = to_vc4_dev(drm);
1039 	struct vc4_hvs *hvs = vc4->hvs;
1040 	struct drm_mm_node *node, *next;
1041 
1042 	if (drm_mm_node_allocated(&vc4->hvs->mitchell_netravali_filter))
1043 		drm_mm_remove_node(&vc4->hvs->mitchell_netravali_filter);
1044 
1045 	drm_mm_for_each_node_safe(node, next, &vc4->hvs->dlist_mm)
1046 		drm_mm_remove_node(node);
1047 
1048 	drm_mm_takedown(&vc4->hvs->dlist_mm);
1049 
1050 	drm_mm_for_each_node_safe(node, next, &vc4->hvs->lbm_mm)
1051 		drm_mm_remove_node(node);
1052 	drm_mm_takedown(&vc4->hvs->lbm_mm);
1053 
1054 	clk_disable_unprepare(hvs->core_clk);
1055 
1056 	vc4->hvs = NULL;
1057 }
1058 
1059 static const struct component_ops vc4_hvs_ops = {
1060 	.bind   = vc4_hvs_bind,
1061 	.unbind = vc4_hvs_unbind,
1062 };
1063 
1064 static int vc4_hvs_dev_probe(struct platform_device *pdev)
1065 {
1066 	return component_add(&pdev->dev, &vc4_hvs_ops);
1067 }
1068 
1069 static void vc4_hvs_dev_remove(struct platform_device *pdev)
1070 {
1071 	component_del(&pdev->dev, &vc4_hvs_ops);
1072 }
1073 
1074 static const struct of_device_id vc4_hvs_dt_match[] = {
1075 	{ .compatible = "brcm,bcm2711-hvs" },
1076 	{ .compatible = "brcm,bcm2835-hvs" },
1077 	{}
1078 };
1079 
1080 struct platform_driver vc4_hvs_driver = {
1081 	.probe = vc4_hvs_dev_probe,
1082 	.remove_new = vc4_hvs_dev_remove,
1083 	.driver = {
1084 		.name = "vc4_hvs",
1085 		.of_match_table = vc4_hvs_dt_match,
1086 	},
1087 };
1088