1/*
2 * rcar_du_crtc.c  --  R-Car Display Unit CRTCs
3 *
4 * Copyright (C) 2013-2014 Renesas Electronics Corporation
5 *
6 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14#include <linux/clk.h>
15#include <linux/mutex.h>
16
17#include <drm/drmP.h>
18#include <drm/drm_atomic.h>
19#include <drm/drm_atomic_helper.h>
20#include <drm/drm_crtc.h>
21#include <drm/drm_crtc_helper.h>
22#include <drm/drm_fb_cma_helper.h>
23#include <drm/drm_gem_cma_helper.h>
24#include <drm/drm_plane_helper.h>
25
26#include "rcar_du_crtc.h"
27#include "rcar_du_drv.h"
28#include "rcar_du_kms.h"
29#include "rcar_du_plane.h"
30#include "rcar_du_regs.h"
31
32static u32 rcar_du_crtc_read(struct rcar_du_crtc *rcrtc, u32 reg)
33{
34	struct rcar_du_device *rcdu = rcrtc->group->dev;
35
36	return rcar_du_read(rcdu, rcrtc->mmio_offset + reg);
37}
38
39static void rcar_du_crtc_write(struct rcar_du_crtc *rcrtc, u32 reg, u32 data)
40{
41	struct rcar_du_device *rcdu = rcrtc->group->dev;
42
43	rcar_du_write(rcdu, rcrtc->mmio_offset + reg, data);
44}
45
46static void rcar_du_crtc_clr(struct rcar_du_crtc *rcrtc, u32 reg, u32 clr)
47{
48	struct rcar_du_device *rcdu = rcrtc->group->dev;
49
50	rcar_du_write(rcdu, rcrtc->mmio_offset + reg,
51		      rcar_du_read(rcdu, rcrtc->mmio_offset + reg) & ~clr);
52}
53
54static void rcar_du_crtc_set(struct rcar_du_crtc *rcrtc, u32 reg, u32 set)
55{
56	struct rcar_du_device *rcdu = rcrtc->group->dev;
57
58	rcar_du_write(rcdu, rcrtc->mmio_offset + reg,
59		      rcar_du_read(rcdu, rcrtc->mmio_offset + reg) | set);
60}
61
62static void rcar_du_crtc_clr_set(struct rcar_du_crtc *rcrtc, u32 reg,
63				 u32 clr, u32 set)
64{
65	struct rcar_du_device *rcdu = rcrtc->group->dev;
66	u32 value = rcar_du_read(rcdu, rcrtc->mmio_offset + reg);
67
68	rcar_du_write(rcdu, rcrtc->mmio_offset + reg, (value & ~clr) | set);
69}
70
71static int rcar_du_crtc_get(struct rcar_du_crtc *rcrtc)
72{
73	int ret;
74
75	ret = clk_prepare_enable(rcrtc->clock);
76	if (ret < 0)
77		return ret;
78
79	ret = clk_prepare_enable(rcrtc->extclock);
80	if (ret < 0)
81		goto error_clock;
82
83	ret = rcar_du_group_get(rcrtc->group);
84	if (ret < 0)
85		goto error_group;
86
87	return 0;
88
89error_group:
90	clk_disable_unprepare(rcrtc->extclock);
91error_clock:
92	clk_disable_unprepare(rcrtc->clock);
93	return ret;
94}
95
96static void rcar_du_crtc_put(struct rcar_du_crtc *rcrtc)
97{
98	rcar_du_group_put(rcrtc->group);
99
100	clk_disable_unprepare(rcrtc->extclock);
101	clk_disable_unprepare(rcrtc->clock);
102}
103
104/* -----------------------------------------------------------------------------
105 * Hardware Setup
106 */
107
108static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc)
109{
110	const struct drm_display_mode *mode = &rcrtc->crtc.state->adjusted_mode;
111	unsigned long mode_clock = mode->clock * 1000;
112	unsigned long clk;
113	u32 value;
114	u32 escr;
115	u32 div;
116
117	/* Compute the clock divisor and select the internal or external dot
118	 * clock based on the requested frequency.
119	 */
120	clk = clk_get_rate(rcrtc->clock);
121	div = DIV_ROUND_CLOSEST(clk, mode_clock);
122	div = clamp(div, 1U, 64U) - 1;
123	escr = div | ESCR_DCLKSEL_CLKS;
124
125	if (rcrtc->extclock) {
126		unsigned long extclk;
127		unsigned long extrate;
128		unsigned long rate;
129		u32 extdiv;
130
131		extclk = clk_get_rate(rcrtc->extclock);
132		extdiv = DIV_ROUND_CLOSEST(extclk, mode_clock);
133		extdiv = clamp(extdiv, 1U, 64U) - 1;
134
135		rate = clk / (div + 1);
136		extrate = extclk / (extdiv + 1);
137
138		if (abs((long)extrate - (long)mode_clock) <
139		    abs((long)rate - (long)mode_clock)) {
140			dev_dbg(rcrtc->group->dev->dev,
141				"crtc%u: using external clock\n", rcrtc->index);
142			escr = extdiv | ESCR_DCLKSEL_DCLKIN;
143		}
144	}
145
146	rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? ESCR2 : ESCR,
147			    escr);
148	rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? OTAR2 : OTAR, 0);
149
150	/* Signal polarities */
151	value = ((mode->flags & DRM_MODE_FLAG_PVSYNC) ? 0 : DSMR_VSL)
152	      | ((mode->flags & DRM_MODE_FLAG_PHSYNC) ? 0 : DSMR_HSL)
153	      | DSMR_DIPM_DE | DSMR_CSPM;
154	rcar_du_crtc_write(rcrtc, DSMR, value);
155
156	/* Display timings */
157	rcar_du_crtc_write(rcrtc, HDSR, mode->htotal - mode->hsync_start - 19);
158	rcar_du_crtc_write(rcrtc, HDER, mode->htotal - mode->hsync_start +
159					mode->hdisplay - 19);
160	rcar_du_crtc_write(rcrtc, HSWR, mode->hsync_end -
161					mode->hsync_start - 1);
162	rcar_du_crtc_write(rcrtc, HCR,  mode->htotal - 1);
163
164	rcar_du_crtc_write(rcrtc, VDSR, mode->crtc_vtotal -
165					mode->crtc_vsync_end - 2);
166	rcar_du_crtc_write(rcrtc, VDER, mode->crtc_vtotal -
167					mode->crtc_vsync_end +
168					mode->crtc_vdisplay - 2);
169	rcar_du_crtc_write(rcrtc, VSPR, mode->crtc_vtotal -
170					mode->crtc_vsync_end +
171					mode->crtc_vsync_start - 1);
172	rcar_du_crtc_write(rcrtc, VCR,  mode->crtc_vtotal - 1);
173
174	rcar_du_crtc_write(rcrtc, DESR,  mode->htotal - mode->hsync_start);
175	rcar_du_crtc_write(rcrtc, DEWR,  mode->hdisplay);
176}
177
178void rcar_du_crtc_route_output(struct drm_crtc *crtc,
179			       enum rcar_du_output output)
180{
181	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
182	struct rcar_du_device *rcdu = rcrtc->group->dev;
183
184	/* Store the route from the CRTC output to the DU output. The DU will be
185	 * configured when starting the CRTC.
186	 */
187	rcrtc->outputs |= BIT(output);
188
189	/* Store RGB routing to DPAD0, the hardware will be configured when
190	 * starting the CRTC.
191	 */
192	if (output == RCAR_DU_OUTPUT_DPAD0)
193		rcdu->dpad0_source = rcrtc->index;
194}
195
196static unsigned int plane_zpos(struct rcar_du_plane *plane)
197{
198	return to_rcar_du_plane_state(plane->plane.state)->zpos;
199}
200
201static const struct rcar_du_format_info *
202plane_format(struct rcar_du_plane *plane)
203{
204	return to_rcar_du_plane_state(plane->plane.state)->format;
205}
206
207static void rcar_du_crtc_update_planes(struct rcar_du_crtc *rcrtc)
208{
209	struct rcar_du_plane *planes[RCAR_DU_NUM_HW_PLANES];
210	unsigned int num_planes = 0;
211	unsigned int prio = 0;
212	unsigned int i;
213	u32 dptsr = 0;
214	u32 dspr = 0;
215
216	for (i = 0; i < ARRAY_SIZE(rcrtc->group->planes.planes); ++i) {
217		struct rcar_du_plane *plane = &rcrtc->group->planes.planes[i];
218		unsigned int j;
219
220		if (plane->plane.state->crtc != &rcrtc->crtc)
221			continue;
222
223		/* Insert the plane in the sorted planes array. */
224		for (j = num_planes++; j > 0; --j) {
225			if (plane_zpos(planes[j-1]) <= plane_zpos(plane))
226				break;
227			planes[j] = planes[j-1];
228		}
229
230		planes[j] = plane;
231		prio += plane_format(plane)->planes * 4;
232	}
233
234	for (i = 0; i < num_planes; ++i) {
235		struct rcar_du_plane *plane = planes[i];
236		struct drm_plane_state *state = plane->plane.state;
237		unsigned int index = to_rcar_du_plane_state(state)->hwindex;
238
239		prio -= 4;
240		dspr |= (index + 1) << prio;
241		dptsr |= DPTSR_PnDK(index) |  DPTSR_PnTS(index);
242
243		if (plane_format(plane)->planes == 2) {
244			index = (index + 1) % 8;
245
246			prio -= 4;
247			dspr |= (index + 1) << prio;
248			dptsr |= DPTSR_PnDK(index) |  DPTSR_PnTS(index);
249		}
250	}
251
252	/* Select display timing and dot clock generator 2 for planes associated
253	 * with superposition controller 2.
254	 */
255	if (rcrtc->index % 2) {
256		/* The DPTSR register is updated when the display controller is
257		 * stopped. We thus need to restart the DU. Once again, sorry
258		 * for the flicker. One way to mitigate the issue would be to
259		 * pre-associate planes with CRTCs (either with a fixed 4/4
260		 * split, or through a module parameter). Flicker would then
261		 * occur only if we need to break the pre-association.
262		 */
263		mutex_lock(&rcrtc->group->lock);
264		if (rcar_du_group_read(rcrtc->group, DPTSR) != dptsr) {
265			rcar_du_group_write(rcrtc->group, DPTSR, dptsr);
266			if (rcrtc->group->used_crtcs)
267				rcar_du_group_restart(rcrtc->group);
268		}
269		mutex_unlock(&rcrtc->group->lock);
270	}
271
272	rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR,
273			    dspr);
274}
275
276/* -----------------------------------------------------------------------------
277 * Page Flip
278 */
279
280void rcar_du_crtc_cancel_page_flip(struct rcar_du_crtc *rcrtc,
281				   struct drm_file *file)
282{
283	struct drm_pending_vblank_event *event;
284	struct drm_device *dev = rcrtc->crtc.dev;
285	unsigned long flags;
286
287	/* Destroy the pending vertical blanking event associated with the
288	 * pending page flip, if any, and disable vertical blanking interrupts.
289	 */
290	spin_lock_irqsave(&dev->event_lock, flags);
291	event = rcrtc->event;
292	if (event && event->base.file_priv == file) {
293		rcrtc->event = NULL;
294		event->base.destroy(&event->base);
295		drm_crtc_vblank_put(&rcrtc->crtc);
296	}
297	spin_unlock_irqrestore(&dev->event_lock, flags);
298}
299
300static void rcar_du_crtc_finish_page_flip(struct rcar_du_crtc *rcrtc)
301{
302	struct drm_pending_vblank_event *event;
303	struct drm_device *dev = rcrtc->crtc.dev;
304	unsigned long flags;
305
306	spin_lock_irqsave(&dev->event_lock, flags);
307	event = rcrtc->event;
308	rcrtc->event = NULL;
309	spin_unlock_irqrestore(&dev->event_lock, flags);
310
311	if (event == NULL)
312		return;
313
314	spin_lock_irqsave(&dev->event_lock, flags);
315	drm_send_vblank_event(dev, rcrtc->index, event);
316	wake_up(&rcrtc->flip_wait);
317	spin_unlock_irqrestore(&dev->event_lock, flags);
318
319	drm_crtc_vblank_put(&rcrtc->crtc);
320}
321
322static bool rcar_du_crtc_page_flip_pending(struct rcar_du_crtc *rcrtc)
323{
324	struct drm_device *dev = rcrtc->crtc.dev;
325	unsigned long flags;
326	bool pending;
327
328	spin_lock_irqsave(&dev->event_lock, flags);
329	pending = rcrtc->event != NULL;
330	spin_unlock_irqrestore(&dev->event_lock, flags);
331
332	return pending;
333}
334
335static void rcar_du_crtc_wait_page_flip(struct rcar_du_crtc *rcrtc)
336{
337	struct rcar_du_device *rcdu = rcrtc->group->dev;
338
339	if (wait_event_timeout(rcrtc->flip_wait,
340			       !rcar_du_crtc_page_flip_pending(rcrtc),
341			       msecs_to_jiffies(50)))
342		return;
343
344	dev_warn(rcdu->dev, "page flip timeout\n");
345
346	rcar_du_crtc_finish_page_flip(rcrtc);
347}
348
349/* -----------------------------------------------------------------------------
350 * Start/Stop and Suspend/Resume
351 */
352
353static void rcar_du_crtc_start(struct rcar_du_crtc *rcrtc)
354{
355	struct drm_crtc *crtc = &rcrtc->crtc;
356	bool interlaced;
357
358	if (rcrtc->started)
359		return;
360
361	/* Set display off and background to black */
362	rcar_du_crtc_write(rcrtc, DOOR, DOOR_RGB(0, 0, 0));
363	rcar_du_crtc_write(rcrtc, BPOR, BPOR_RGB(0, 0, 0));
364
365	/* Configure display timings and output routing */
366	rcar_du_crtc_set_display_timing(rcrtc);
367	rcar_du_group_set_routing(rcrtc->group);
368
369	/* Start with all planes disabled. */
370	rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR, 0);
371
372	/* Select master sync mode. This enables display operation in master
373	 * sync mode (with the HSYNC and VSYNC signals configured as outputs and
374	 * actively driven).
375	 */
376	interlaced = rcrtc->crtc.mode.flags & DRM_MODE_FLAG_INTERLACE;
377	rcar_du_crtc_clr_set(rcrtc, DSYSR, DSYSR_TVM_MASK | DSYSR_SCM_MASK,
378			     (interlaced ? DSYSR_SCM_INT_VIDEO : 0) |
379			     DSYSR_TVM_MASTER);
380
381	rcar_du_group_start_stop(rcrtc->group, true);
382
383	/* Turn vertical blanking interrupt reporting back on. */
384	drm_crtc_vblank_on(crtc);
385
386	rcrtc->started = true;
387}
388
389static void rcar_du_crtc_stop(struct rcar_du_crtc *rcrtc)
390{
391	struct drm_crtc *crtc = &rcrtc->crtc;
392
393	if (!rcrtc->started)
394		return;
395
396	/* Disable vertical blanking interrupt reporting. We first need to wait
397	 * for page flip completion before stopping the CRTC as userspace
398	 * expects page flips to eventually complete.
399	 */
400	rcar_du_crtc_wait_page_flip(rcrtc);
401	drm_crtc_vblank_off(crtc);
402
403	/* Select switch sync mode. This stops display operation and configures
404	 * the HSYNC and VSYNC signals as inputs.
405	 */
406	rcar_du_crtc_clr_set(rcrtc, DSYSR, DSYSR_TVM_MASK, DSYSR_TVM_SWITCH);
407
408	rcar_du_group_start_stop(rcrtc->group, false);
409
410	rcrtc->started = false;
411}
412
413void rcar_du_crtc_suspend(struct rcar_du_crtc *rcrtc)
414{
415	rcar_du_crtc_stop(rcrtc);
416	rcar_du_crtc_put(rcrtc);
417}
418
419void rcar_du_crtc_resume(struct rcar_du_crtc *rcrtc)
420{
421	unsigned int i;
422
423	if (!rcrtc->enabled)
424		return;
425
426	rcar_du_crtc_get(rcrtc);
427	rcar_du_crtc_start(rcrtc);
428
429	/* Commit the planes state. */
430	for (i = 0; i < ARRAY_SIZE(rcrtc->group->planes.planes); ++i) {
431		struct rcar_du_plane *plane = &rcrtc->group->planes.planes[i];
432
433		if (plane->plane.state->crtc != &rcrtc->crtc)
434			continue;
435
436		rcar_du_plane_setup(plane);
437	}
438
439	rcar_du_crtc_update_planes(rcrtc);
440}
441
442/* -----------------------------------------------------------------------------
443 * CRTC Functions
444 */
445
446static void rcar_du_crtc_enable(struct drm_crtc *crtc)
447{
448	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
449
450	if (rcrtc->enabled)
451		return;
452
453	rcar_du_crtc_get(rcrtc);
454	rcar_du_crtc_start(rcrtc);
455
456	rcrtc->enabled = true;
457}
458
459static void rcar_du_crtc_disable(struct drm_crtc *crtc)
460{
461	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
462
463	if (!rcrtc->enabled)
464		return;
465
466	rcar_du_crtc_stop(rcrtc);
467	rcar_du_crtc_put(rcrtc);
468
469	rcrtc->enabled = false;
470	rcrtc->outputs = 0;
471}
472
473static bool rcar_du_crtc_mode_fixup(struct drm_crtc *crtc,
474				    const struct drm_display_mode *mode,
475				    struct drm_display_mode *adjusted_mode)
476{
477	/* TODO Fixup modes */
478	return true;
479}
480
481static void rcar_du_crtc_atomic_begin(struct drm_crtc *crtc)
482{
483	struct drm_pending_vblank_event *event = crtc->state->event;
484	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
485	struct drm_device *dev = rcrtc->crtc.dev;
486	unsigned long flags;
487
488	if (event) {
489		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
490
491		spin_lock_irqsave(&dev->event_lock, flags);
492		rcrtc->event = event;
493		spin_unlock_irqrestore(&dev->event_lock, flags);
494	}
495}
496
497static void rcar_du_crtc_atomic_flush(struct drm_crtc *crtc)
498{
499	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
500
501	rcar_du_crtc_update_planes(rcrtc);
502}
503
504static const struct drm_crtc_helper_funcs crtc_helper_funcs = {
505	.mode_fixup = rcar_du_crtc_mode_fixup,
506	.disable = rcar_du_crtc_disable,
507	.enable = rcar_du_crtc_enable,
508	.atomic_begin = rcar_du_crtc_atomic_begin,
509	.atomic_flush = rcar_du_crtc_atomic_flush,
510};
511
512static const struct drm_crtc_funcs crtc_funcs = {
513	.reset = drm_atomic_helper_crtc_reset,
514	.destroy = drm_crtc_cleanup,
515	.set_config = drm_atomic_helper_set_config,
516	.page_flip = drm_atomic_helper_page_flip,
517	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
518	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
519};
520
521/* -----------------------------------------------------------------------------
522 * Interrupt Handling
523 */
524
525static irqreturn_t rcar_du_crtc_irq(int irq, void *arg)
526{
527	struct rcar_du_crtc *rcrtc = arg;
528	irqreturn_t ret = IRQ_NONE;
529	u32 status;
530
531	status = rcar_du_crtc_read(rcrtc, DSSR);
532	rcar_du_crtc_write(rcrtc, DSRCR, status & DSRCR_MASK);
533
534	if (status & DSSR_FRM) {
535		drm_handle_vblank(rcrtc->crtc.dev, rcrtc->index);
536		rcar_du_crtc_finish_page_flip(rcrtc);
537		ret = IRQ_HANDLED;
538	}
539
540	return ret;
541}
542
543/* -----------------------------------------------------------------------------
544 * Initialization
545 */
546
547int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int index)
548{
549	static const unsigned int mmio_offsets[] = {
550		DU0_REG_OFFSET, DU1_REG_OFFSET, DU2_REG_OFFSET
551	};
552
553	struct rcar_du_device *rcdu = rgrp->dev;
554	struct platform_device *pdev = to_platform_device(rcdu->dev);
555	struct rcar_du_crtc *rcrtc = &rcdu->crtcs[index];
556	struct drm_crtc *crtc = &rcrtc->crtc;
557	unsigned int irqflags;
558	struct clk *clk;
559	char clk_name[9];
560	char *name;
561	int irq;
562	int ret;
563
564	/* Get the CRTC clock and the optional external clock. */
565	if (rcar_du_has(rcdu, RCAR_DU_FEATURE_CRTC_IRQ_CLOCK)) {
566		sprintf(clk_name, "du.%u", index);
567		name = clk_name;
568	} else {
569		name = NULL;
570	}
571
572	rcrtc->clock = devm_clk_get(rcdu->dev, name);
573	if (IS_ERR(rcrtc->clock)) {
574		dev_err(rcdu->dev, "no clock for CRTC %u\n", index);
575		return PTR_ERR(rcrtc->clock);
576	}
577
578	sprintf(clk_name, "dclkin.%u", index);
579	clk = devm_clk_get(rcdu->dev, clk_name);
580	if (!IS_ERR(clk)) {
581		rcrtc->extclock = clk;
582	} else if (PTR_ERR(rcrtc->clock) == -EPROBE_DEFER) {
583		dev_info(rcdu->dev, "can't get external clock %u\n", index);
584		return -EPROBE_DEFER;
585	}
586
587	init_waitqueue_head(&rcrtc->flip_wait);
588
589	rcrtc->group = rgrp;
590	rcrtc->mmio_offset = mmio_offsets[index];
591	rcrtc->index = index;
592	rcrtc->enabled = false;
593
594	ret = drm_crtc_init_with_planes(rcdu->ddev, crtc,
595					&rgrp->planes.planes[index % 2].plane,
596					NULL, &crtc_funcs);
597	if (ret < 0)
598		return ret;
599
600	drm_crtc_helper_add(crtc, &crtc_helper_funcs);
601
602	/* Start with vertical blanking interrupt reporting disabled. */
603	drm_crtc_vblank_off(crtc);
604
605	/* Register the interrupt handler. */
606	if (rcar_du_has(rcdu, RCAR_DU_FEATURE_CRTC_IRQ_CLOCK)) {
607		irq = platform_get_irq(pdev, index);
608		irqflags = 0;
609	} else {
610		irq = platform_get_irq(pdev, 0);
611		irqflags = IRQF_SHARED;
612	}
613
614	if (irq < 0) {
615		dev_err(rcdu->dev, "no IRQ for CRTC %u\n", index);
616		return irq;
617	}
618
619	ret = devm_request_irq(rcdu->dev, irq, rcar_du_crtc_irq, irqflags,
620			       dev_name(rcdu->dev), rcrtc);
621	if (ret < 0) {
622		dev_err(rcdu->dev,
623			"failed to register IRQ for CRTC %u\n", index);
624		return ret;
625	}
626
627	return 0;
628}
629
630void rcar_du_crtc_enable_vblank(struct rcar_du_crtc *rcrtc, bool enable)
631{
632	if (enable) {
633		rcar_du_crtc_write(rcrtc, DSRCR, DSRCR_VBCL);
634		rcar_du_crtc_set(rcrtc, DIER, DIER_VBE);
635	} else {
636		rcar_du_crtc_clr(rcrtc, DIER, DIER_VBE);
637	}
638}
639