1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012 Texas Instruments
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7#include <linux/delay.h>
8#include <linux/dma-mapping.h>
9#include <linux/of_graph.h>
10#include <linux/pm_runtime.h>
11
12#include <drm/drm_atomic.h>
13#include <drm/drm_atomic_helper.h>
14#include <drm/drm_crtc.h>
15#include <drm/drm_fb_cma_helper.h>
16#include <drm/drm_fourcc.h>
17#include <drm/drm_gem_cma_helper.h>
18#include <drm/drm_modeset_helper_vtables.h>
19#include <drm/drm_print.h>
20#include <drm/drm_vblank.h>
21
22#include "tilcdc_drv.h"
23#include "tilcdc_regs.h"
24
25#define TILCDC_VBLANK_SAFETY_THRESHOLD_US	1000
26#define TILCDC_PALETTE_SIZE			32
27#define TILCDC_PALETTE_FIRST_ENTRY		0x4000
28
29struct tilcdc_crtc {
30	struct drm_crtc base;
31
32	struct drm_plane primary;
33	const struct tilcdc_panel_info *info;
34	struct drm_pending_vblank_event *event;
35	struct mutex enable_lock;
36	bool enabled;
37	bool shutdown;
38	wait_queue_head_t frame_done_wq;
39	bool frame_done;
40	spinlock_t irq_lock;
41
42	unsigned int lcd_fck_rate;
43
44	ktime_t last_vblank;
45	unsigned int hvtotal_us;
46
47	struct drm_framebuffer *next_fb;
48
49	/* Only set if an external encoder is connected */
50	bool simulate_vesa_sync;
51
52	int sync_lost_count;
53	bool frame_intact;
54	struct work_struct recover_work;
55
56	dma_addr_t palette_dma_handle;
57	u16 *palette_base;
58	struct completion palette_loaded;
59};
60#define to_tilcdc_crtc(x) container_of(x, struct tilcdc_crtc, base)
61
62static void set_scanout(struct drm_crtc *crtc, struct drm_framebuffer *fb)
63{
64	struct drm_device *dev = crtc->dev;
65	struct tilcdc_drm_private *priv = dev->dev_private;
66	struct drm_gem_cma_object *gem;
67	dma_addr_t start, end;
68	u64 dma_base_and_ceiling;
69
70	gem = drm_fb_cma_get_gem_obj(fb, 0);
71
72	start = gem->paddr + fb->offsets[0] +
73		crtc->y * fb->pitches[0] +
74		crtc->x * fb->format->cpp[0];
75
76	end = start + (crtc->mode.vdisplay * fb->pitches[0]);
77
78	/* Write LCDC_DMA_FB_BASE_ADDR_0_REG and LCDC_DMA_FB_CEILING_ADDR_0_REG
79	 * with a single insruction, if available. This should make it more
80	 * unlikely that LCDC would fetch the DMA addresses in the middle of
81	 * an update.
82	 */
83	if (priv->rev == 1)
84		end -= 1;
85
86	dma_base_and_ceiling = (u64)end << 32 | start;
87	tilcdc_write64(dev, LCDC_DMA_FB_BASE_ADDR_0_REG, dma_base_and_ceiling);
88}
89
90/*
91 * The driver currently only supports only true color formats. For
92 * true color the palette block is bypassed, but a 32 byte palette
93 * should still be loaded. The first 16-bit entry must be 0x4000 while
94 * all other entries must be zeroed.
95 */
96static void tilcdc_crtc_load_palette(struct drm_crtc *crtc)
97{
98	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
99	struct drm_device *dev = crtc->dev;
100	struct tilcdc_drm_private *priv = dev->dev_private;
101	int ret;
102
103	reinit_completion(&tilcdc_crtc->palette_loaded);
104
105	/* Tell the LCDC where the palette is located. */
106	tilcdc_write(dev, LCDC_DMA_FB_BASE_ADDR_0_REG,
107		     tilcdc_crtc->palette_dma_handle);
108	tilcdc_write(dev, LCDC_DMA_FB_CEILING_ADDR_0_REG,
109		     (u32) tilcdc_crtc->palette_dma_handle +
110		     TILCDC_PALETTE_SIZE - 1);
111
112	/* Set dma load mode for palette loading only. */
113	tilcdc_write_mask(dev, LCDC_RASTER_CTRL_REG,
114			  LCDC_PALETTE_LOAD_MODE(PALETTE_ONLY),
115			  LCDC_PALETTE_LOAD_MODE_MASK);
116
117	/* Enable DMA Palette Loaded Interrupt */
118	if (priv->rev == 1)
119		tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_V1_PL_INT_ENA);
120	else
121		tilcdc_write(dev, LCDC_INT_ENABLE_SET_REG, LCDC_V2_PL_INT_ENA);
122
123	/* Enable LCDC DMA and wait for palette to be loaded. */
124	tilcdc_clear_irqstatus(dev, 0xffffffff);
125	tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
126
127	ret = wait_for_completion_timeout(&tilcdc_crtc->palette_loaded,
128					  msecs_to_jiffies(50));
129	if (ret == 0)
130		dev_err(dev->dev, "%s: Palette loading timeout", __func__);
131
132	/* Disable LCDC DMA and DMA Palette Loaded Interrupt. */
133	tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
134	if (priv->rev == 1)
135		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_V1_PL_INT_ENA);
136	else
137		tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG, LCDC_V2_PL_INT_ENA);
138}
139
140static void tilcdc_crtc_enable_irqs(struct drm_device *dev)
141{
142	struct tilcdc_drm_private *priv = dev->dev_private;
143
144	tilcdc_clear_irqstatus(dev, 0xffffffff);
145
146	if (priv->rev == 1) {
147		tilcdc_set(dev, LCDC_RASTER_CTRL_REG,
148			LCDC_V1_SYNC_LOST_INT_ENA | LCDC_V1_FRAME_DONE_INT_ENA |
149			LCDC_V1_UNDERFLOW_INT_ENA);
150		tilcdc_set(dev, LCDC_DMA_CTRL_REG,
151			LCDC_V1_END_OF_FRAME_INT_ENA);
152	} else {
153		tilcdc_write(dev, LCDC_INT_ENABLE_SET_REG,
154			LCDC_V2_UNDERFLOW_INT_ENA |
155			LCDC_V2_END_OF_FRAME0_INT_ENA |
156			LCDC_FRAME_DONE | LCDC_SYNC_LOST);
157	}
158}
159
160static void tilcdc_crtc_disable_irqs(struct drm_device *dev)
161{
162	struct tilcdc_drm_private *priv = dev->dev_private;
163
164	/* disable irqs that we might have enabled: */
165	if (priv->rev == 1) {
166		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
167			LCDC_V1_SYNC_LOST_INT_ENA | LCDC_V1_FRAME_DONE_INT_ENA |
168			LCDC_V1_UNDERFLOW_INT_ENA | LCDC_V1_PL_INT_ENA);
169		tilcdc_clear(dev, LCDC_DMA_CTRL_REG,
170			LCDC_V1_END_OF_FRAME_INT_ENA);
171	} else {
172		tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
173			LCDC_V2_UNDERFLOW_INT_ENA | LCDC_V2_PL_INT_ENA |
174			LCDC_V2_END_OF_FRAME0_INT_ENA |
175			LCDC_FRAME_DONE | LCDC_SYNC_LOST);
176	}
177}
178
179static void reset(struct drm_crtc *crtc)
180{
181	struct drm_device *dev = crtc->dev;
182	struct tilcdc_drm_private *priv = dev->dev_private;
183
184	if (priv->rev != 2)
185		return;
186
187	tilcdc_set(dev, LCDC_CLK_RESET_REG, LCDC_CLK_MAIN_RESET);
188	usleep_range(250, 1000);
189	tilcdc_clear(dev, LCDC_CLK_RESET_REG, LCDC_CLK_MAIN_RESET);
190}
191
192/*
193 * Calculate the percentage difference between the requested pixel clock rate
194 * and the effective rate resulting from calculating the clock divider value.
195 */
196static unsigned int tilcdc_pclk_diff(unsigned long rate,
197				     unsigned long real_rate)
198{
199	int r = rate / 100, rr = real_rate / 100;
200
201	return (unsigned int)(abs(((rr - r) * 100) / r));
202}
203
204static void tilcdc_crtc_set_clk(struct drm_crtc *crtc)
205{
206	struct drm_device *dev = crtc->dev;
207	struct tilcdc_drm_private *priv = dev->dev_private;
208	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
209	unsigned long clk_rate, real_rate, req_rate;
210	unsigned int clkdiv;
211	int ret;
212
213	clkdiv = 2; /* first try using a standard divider of 2 */
214
215	/* mode.clock is in KHz, set_rate wants parameter in Hz */
216	req_rate = crtc->mode.clock * 1000;
217
218	ret = clk_set_rate(priv->clk, req_rate * clkdiv);
219	clk_rate = clk_get_rate(priv->clk);
220	if (ret < 0 || tilcdc_pclk_diff(req_rate, clk_rate) > 5) {
221		/*
222		 * If we fail to set the clock rate (some architectures don't
223		 * use the common clock framework yet and may not implement
224		 * all the clk API calls for every clock), try the next best
225		 * thing: adjusting the clock divider, unless clk_get_rate()
226		 * failed as well.
227		 */
228		if (!clk_rate) {
229			/* Nothing more we can do. Just bail out. */
230			dev_err(dev->dev,
231				"failed to set the pixel clock - unable to read current lcdc clock rate\n");
232			return;
233		}
234
235		clkdiv = DIV_ROUND_CLOSEST(clk_rate, req_rate);
236
237		/*
238		 * Emit a warning if the real clock rate resulting from the
239		 * calculated divider differs much from the requested rate.
240		 *
241		 * 5% is an arbitrary value - LCDs are usually quite tolerant
242		 * about pixel clock rates.
243		 */
244		real_rate = clkdiv * req_rate;
245
246		if (tilcdc_pclk_diff(clk_rate, real_rate) > 5) {
247			dev_warn(dev->dev,
248				 "effective pixel clock rate (%luHz) differs from the calculated rate (%luHz)\n",
249				 clk_rate, real_rate);
250		}
251	}
252
253	tilcdc_crtc->lcd_fck_rate = clk_rate;
254
255	DBG("lcd_clk=%u, mode clock=%d, div=%u",
256	    tilcdc_crtc->lcd_fck_rate, crtc->mode.clock, clkdiv);
257
258	/* Configure the LCD clock divisor. */
259	tilcdc_write(dev, LCDC_CTRL_REG, LCDC_CLK_DIVISOR(clkdiv) |
260		     LCDC_RASTER_MODE);
261
262	if (priv->rev == 2)
263		tilcdc_set(dev, LCDC_CLK_ENABLE_REG,
264				LCDC_V2_DMA_CLK_EN | LCDC_V2_LIDD_CLK_EN |
265				LCDC_V2_CORE_CLK_EN);
266}
267
268static uint tilcdc_mode_hvtotal(const struct drm_display_mode *mode)
269{
270	return (uint) div_u64(1000llu * mode->htotal * mode->vtotal,
271			      mode->clock);
272}
273
274static void tilcdc_crtc_set_mode(struct drm_crtc *crtc)
275{
276	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
277	struct drm_device *dev = crtc->dev;
278	struct tilcdc_drm_private *priv = dev->dev_private;
279	const struct tilcdc_panel_info *info = tilcdc_crtc->info;
280	uint32_t reg, hbp, hfp, hsw, vbp, vfp, vsw;
281	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
282	struct drm_framebuffer *fb = crtc->primary->state->fb;
283
284	if (WARN_ON(!info))
285		return;
286
287	if (WARN_ON(!fb))
288		return;
289
290	/* Configure the Burst Size and fifo threshold of DMA: */
291	reg = tilcdc_read(dev, LCDC_DMA_CTRL_REG) & ~0x00000770;
292	switch (info->dma_burst_sz) {
293	case 1:
294		reg |= LCDC_DMA_BURST_SIZE(LCDC_DMA_BURST_1);
295		break;
296	case 2:
297		reg |= LCDC_DMA_BURST_SIZE(LCDC_DMA_BURST_2);
298		break;
299	case 4:
300		reg |= LCDC_DMA_BURST_SIZE(LCDC_DMA_BURST_4);
301		break;
302	case 8:
303		reg |= LCDC_DMA_BURST_SIZE(LCDC_DMA_BURST_8);
304		break;
305	case 16:
306		reg |= LCDC_DMA_BURST_SIZE(LCDC_DMA_BURST_16);
307		break;
308	default:
309		dev_err(dev->dev, "invalid burst size\n");
310		return;
311	}
312	reg |= (info->fifo_th << 8);
313	tilcdc_write(dev, LCDC_DMA_CTRL_REG, reg);
314
315	/* Configure timings: */
316	hbp = mode->htotal - mode->hsync_end;
317	hfp = mode->hsync_start - mode->hdisplay;
318	hsw = mode->hsync_end - mode->hsync_start;
319	vbp = mode->vtotal - mode->vsync_end;
320	vfp = mode->vsync_start - mode->vdisplay;
321	vsw = mode->vsync_end - mode->vsync_start;
322
323	DBG("%dx%d, hbp=%u, hfp=%u, hsw=%u, vbp=%u, vfp=%u, vsw=%u",
324	    mode->hdisplay, mode->vdisplay, hbp, hfp, hsw, vbp, vfp, vsw);
325
326	/* Set AC Bias Period and Number of Transitions per Interrupt: */
327	reg = tilcdc_read(dev, LCDC_RASTER_TIMING_2_REG) & ~0x000fff00;
328	reg |= LCDC_AC_BIAS_FREQUENCY(info->ac_bias) |
329		LCDC_AC_BIAS_TRANSITIONS_PER_INT(info->ac_bias_intrpt);
330
331	/*
332	 * subtract one from hfp, hbp, hsw because the hardware uses
333	 * a value of 0 as 1
334	 */
335	if (priv->rev == 2) {
336		/* clear bits we're going to set */
337		reg &= ~0x78000033;
338		reg |= ((hfp-1) & 0x300) >> 8;
339		reg |= ((hbp-1) & 0x300) >> 4;
340		reg |= ((hsw-1) & 0x3c0) << 21;
341	}
342	tilcdc_write(dev, LCDC_RASTER_TIMING_2_REG, reg);
343
344	reg = (((mode->hdisplay >> 4) - 1) << 4) |
345		(((hbp-1) & 0xff) << 24) |
346		(((hfp-1) & 0xff) << 16) |
347		(((hsw-1) & 0x3f) << 10);
348	if (priv->rev == 2)
349		reg |= (((mode->hdisplay >> 4) - 1) & 0x40) >> 3;
350	tilcdc_write(dev, LCDC_RASTER_TIMING_0_REG, reg);
351
352	reg = ((mode->vdisplay - 1) & 0x3ff) |
353		((vbp & 0xff) << 24) |
354		((vfp & 0xff) << 16) |
355		(((vsw-1) & 0x3f) << 10);
356	tilcdc_write(dev, LCDC_RASTER_TIMING_1_REG, reg);
357
358	/*
359	 * be sure to set Bit 10 for the V2 LCDC controller,
360	 * otherwise limited to 1024 pixels width, stopping
361	 * 1920x1080 being supported.
362	 */
363	if (priv->rev == 2) {
364		if ((mode->vdisplay - 1) & 0x400) {
365			tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG,
366				LCDC_LPP_B10);
367		} else {
368			tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG,
369				LCDC_LPP_B10);
370		}
371	}
372
373	/* Configure display type: */
374	reg = tilcdc_read(dev, LCDC_RASTER_CTRL_REG) &
375		~(LCDC_TFT_MODE | LCDC_MONO_8BIT_MODE | LCDC_MONOCHROME_MODE |
376		  LCDC_V2_TFT_24BPP_MODE | LCDC_V2_TFT_24BPP_UNPACK |
377		  0x000ff000 /* Palette Loading Delay bits */);
378	reg |= LCDC_TFT_MODE; /* no monochrome/passive support */
379	if (info->tft_alt_mode)
380		reg |= LCDC_TFT_ALT_ENABLE;
381	if (priv->rev == 2) {
382		switch (fb->format->format) {
383		case DRM_FORMAT_BGR565:
384		case DRM_FORMAT_RGB565:
385			break;
386		case DRM_FORMAT_XBGR8888:
387		case DRM_FORMAT_XRGB8888:
388			reg |= LCDC_V2_TFT_24BPP_UNPACK;
389			fallthrough;
390		case DRM_FORMAT_BGR888:
391		case DRM_FORMAT_RGB888:
392			reg |= LCDC_V2_TFT_24BPP_MODE;
393			break;
394		default:
395			dev_err(dev->dev, "invalid pixel format\n");
396			return;
397		}
398	}
399	reg |= info->fdd < 12;
400	tilcdc_write(dev, LCDC_RASTER_CTRL_REG, reg);
401
402	if (info->invert_pxl_clk)
403		tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_PIXEL_CLOCK);
404	else
405		tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_PIXEL_CLOCK);
406
407	if (info->sync_ctrl)
408		tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG, LCDC_SYNC_CTRL);
409	else
410		tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG, LCDC_SYNC_CTRL);
411
412	if (info->sync_edge)
413		tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG, LCDC_SYNC_EDGE);
414	else
415		tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG, LCDC_SYNC_EDGE);
416
417	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
418		tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_HSYNC);
419	else
420		tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_HSYNC);
421
422	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
423		tilcdc_set(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_VSYNC);
424	else
425		tilcdc_clear(dev, LCDC_RASTER_TIMING_2_REG, LCDC_INVERT_VSYNC);
426
427	if (info->raster_order)
428		tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ORDER);
429	else
430		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ORDER);
431
432	tilcdc_crtc_set_clk(crtc);
433
434	tilcdc_crtc_load_palette(crtc);
435
436	set_scanout(crtc, fb);
437
438	crtc->hwmode = crtc->state->adjusted_mode;
439
440	tilcdc_crtc->hvtotal_us =
441		tilcdc_mode_hvtotal(&crtc->hwmode);
442}
443
444static void tilcdc_crtc_enable(struct drm_crtc *crtc)
445{
446	struct drm_device *dev = crtc->dev;
447	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
448	unsigned long flags;
449
450	mutex_lock(&tilcdc_crtc->enable_lock);
451	if (tilcdc_crtc->enabled || tilcdc_crtc->shutdown) {
452		mutex_unlock(&tilcdc_crtc->enable_lock);
453		return;
454	}
455
456	pm_runtime_get_sync(dev->dev);
457
458	reset(crtc);
459
460	tilcdc_crtc_set_mode(crtc);
461
462	tilcdc_crtc_enable_irqs(dev);
463
464	tilcdc_clear(dev, LCDC_DMA_CTRL_REG, LCDC_DUAL_FRAME_BUFFER_ENABLE);
465	tilcdc_write_mask(dev, LCDC_RASTER_CTRL_REG,
466			  LCDC_PALETTE_LOAD_MODE(DATA_ONLY),
467			  LCDC_PALETTE_LOAD_MODE_MASK);
468
469	/* There is no real chance for a race here as the time stamp
470	 * is taken before the raster DMA is started. The spin-lock is
471	 * taken to have a memory barrier after taking the time-stamp
472	 * and to avoid a context switch between taking the stamp and
473	 * enabling the raster.
474	 */
475	spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags);
476	tilcdc_crtc->last_vblank = ktime_get();
477	tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
478	spin_unlock_irqrestore(&tilcdc_crtc->irq_lock, flags);
479
480	drm_crtc_vblank_on(crtc);
481
482	tilcdc_crtc->enabled = true;
483	mutex_unlock(&tilcdc_crtc->enable_lock);
484}
485
486static void tilcdc_crtc_atomic_enable(struct drm_crtc *crtc,
487				      struct drm_crtc_state *old_state)
488{
489	tilcdc_crtc_enable(crtc);
490}
491
492static void tilcdc_crtc_off(struct drm_crtc *crtc, bool shutdown)
493{
494	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
495	struct drm_device *dev = crtc->dev;
496	int ret;
497
498	mutex_lock(&tilcdc_crtc->enable_lock);
499	if (shutdown)
500		tilcdc_crtc->shutdown = true;
501	if (!tilcdc_crtc->enabled) {
502		mutex_unlock(&tilcdc_crtc->enable_lock);
503		return;
504	}
505	tilcdc_crtc->frame_done = false;
506	tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
507
508	/*
509	 * Wait for framedone irq which will still come before putting
510	 * things to sleep..
511	 */
512	ret = wait_event_timeout(tilcdc_crtc->frame_done_wq,
513				 tilcdc_crtc->frame_done,
514				 msecs_to_jiffies(500));
515	if (ret == 0)
516		dev_err(dev->dev, "%s: timeout waiting for framedone\n",
517			__func__);
518
519	drm_crtc_vblank_off(crtc);
520
521	spin_lock_irq(&crtc->dev->event_lock);
522
523	if (crtc->state->event) {
524		drm_crtc_send_vblank_event(crtc, crtc->state->event);
525		crtc->state->event = NULL;
526	}
527
528	spin_unlock_irq(&crtc->dev->event_lock);
529
530	tilcdc_crtc_disable_irqs(dev);
531
532	pm_runtime_put_sync(dev->dev);
533
534	tilcdc_crtc->enabled = false;
535	mutex_unlock(&tilcdc_crtc->enable_lock);
536}
537
538static void tilcdc_crtc_disable(struct drm_crtc *crtc)
539{
540	tilcdc_crtc_off(crtc, false);
541}
542
543static void tilcdc_crtc_atomic_disable(struct drm_crtc *crtc,
544				       struct drm_crtc_state *old_state)
545{
546	tilcdc_crtc_disable(crtc);
547}
548
549static void tilcdc_crtc_atomic_flush(struct drm_crtc *crtc,
550				     struct drm_crtc_state *old_state)
551{
552	if (!crtc->state->event)
553		return;
554
555	spin_lock_irq(&crtc->dev->event_lock);
556	drm_crtc_send_vblank_event(crtc, crtc->state->event);
557	crtc->state->event = NULL;
558	spin_unlock_irq(&crtc->dev->event_lock);
559}
560
561void tilcdc_crtc_shutdown(struct drm_crtc *crtc)
562{
563	tilcdc_crtc_off(crtc, true);
564}
565
566static bool tilcdc_crtc_is_on(struct drm_crtc *crtc)
567{
568	return crtc->state && crtc->state->enable && crtc->state->active;
569}
570
571static void tilcdc_crtc_recover_work(struct work_struct *work)
572{
573	struct tilcdc_crtc *tilcdc_crtc =
574		container_of(work, struct tilcdc_crtc, recover_work);
575	struct drm_crtc *crtc = &tilcdc_crtc->base;
576
577	dev_info(crtc->dev->dev, "%s: Reset CRTC", __func__);
578
579	drm_modeset_lock(&crtc->mutex, NULL);
580
581	if (!tilcdc_crtc_is_on(crtc))
582		goto out;
583
584	tilcdc_crtc_disable(crtc);
585	tilcdc_crtc_enable(crtc);
586out:
587	drm_modeset_unlock(&crtc->mutex);
588}
589
590static void tilcdc_crtc_destroy(struct drm_crtc *crtc)
591{
592	struct tilcdc_drm_private *priv = crtc->dev->dev_private;
593
594	tilcdc_crtc_shutdown(crtc);
595
596	flush_workqueue(priv->wq);
597
598	of_node_put(crtc->port);
599	drm_crtc_cleanup(crtc);
600}
601
602int tilcdc_crtc_update_fb(struct drm_crtc *crtc,
603		struct drm_framebuffer *fb,
604		struct drm_pending_vblank_event *event)
605{
606	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
607	struct drm_device *dev = crtc->dev;
608
609	if (tilcdc_crtc->event) {
610		dev_err(dev->dev, "already pending page flip!\n");
611		return -EBUSY;
612	}
613
614	tilcdc_crtc->event = event;
615
616	mutex_lock(&tilcdc_crtc->enable_lock);
617
618	if (tilcdc_crtc->enabled) {
619		unsigned long flags;
620		ktime_t next_vblank;
621		s64 tdiff;
622
623		spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags);
624
625		next_vblank = ktime_add_us(tilcdc_crtc->last_vblank,
626					   tilcdc_crtc->hvtotal_us);
627		tdiff = ktime_to_us(ktime_sub(next_vblank, ktime_get()));
628
629		if (tdiff < TILCDC_VBLANK_SAFETY_THRESHOLD_US)
630			tilcdc_crtc->next_fb = fb;
631		else
632			set_scanout(crtc, fb);
633
634		spin_unlock_irqrestore(&tilcdc_crtc->irq_lock, flags);
635	}
636
637	mutex_unlock(&tilcdc_crtc->enable_lock);
638
639	return 0;
640}
641
642static bool tilcdc_crtc_mode_fixup(struct drm_crtc *crtc,
643		const struct drm_display_mode *mode,
644		struct drm_display_mode *adjusted_mode)
645{
646	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
647
648	if (!tilcdc_crtc->simulate_vesa_sync)
649		return true;
650
651	/*
652	 * tilcdc does not generate VESA-compliant sync but aligns
653	 * VS on the second edge of HS instead of first edge.
654	 * We use adjusted_mode, to fixup sync by aligning both rising
655	 * edges and add HSKEW offset to fix the sync.
656	 */
657	adjusted_mode->hskew = mode->hsync_end - mode->hsync_start;
658	adjusted_mode->flags |= DRM_MODE_FLAG_HSKEW;
659
660	if (mode->flags & DRM_MODE_FLAG_NHSYNC) {
661		adjusted_mode->flags |= DRM_MODE_FLAG_PHSYNC;
662		adjusted_mode->flags &= ~DRM_MODE_FLAG_NHSYNC;
663	} else {
664		adjusted_mode->flags |= DRM_MODE_FLAG_NHSYNC;
665		adjusted_mode->flags &= ~DRM_MODE_FLAG_PHSYNC;
666	}
667
668	return true;
669}
670
671static int tilcdc_crtc_atomic_check(struct drm_crtc *crtc,
672				    struct drm_crtc_state *state)
673{
674	/* If we are not active we don't care */
675	if (!state->active)
676		return 0;
677
678	if (state->state->planes[0].ptr != crtc->primary ||
679	    state->state->planes[0].state == NULL ||
680	    state->state->planes[0].state->crtc != crtc) {
681		dev_dbg(crtc->dev->dev, "CRTC primary plane must be present");
682		return -EINVAL;
683	}
684
685	return 0;
686}
687
688static int tilcdc_crtc_enable_vblank(struct drm_crtc *crtc)
689{
690	return 0;
691}
692
693static void tilcdc_crtc_disable_vblank(struct drm_crtc *crtc)
694{
695}
696
697static void tilcdc_crtc_reset(struct drm_crtc *crtc)
698{
699	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
700	struct drm_device *dev = crtc->dev;
701	int ret;
702
703	drm_atomic_helper_crtc_reset(crtc);
704
705	/* Turn the raster off if it for some reason is on. */
706	pm_runtime_get_sync(dev->dev);
707	if (tilcdc_read(dev, LCDC_RASTER_CTRL_REG) & LCDC_RASTER_ENABLE) {
708		/* Enable DMA Frame Done Interrupt */
709		tilcdc_write(dev, LCDC_INT_ENABLE_SET_REG, LCDC_FRAME_DONE);
710		tilcdc_clear_irqstatus(dev, 0xffffffff);
711
712		tilcdc_crtc->frame_done = false;
713		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
714
715		ret = wait_event_timeout(tilcdc_crtc->frame_done_wq,
716					 tilcdc_crtc->frame_done,
717					 msecs_to_jiffies(500));
718		if (ret == 0)
719			dev_err(dev->dev, "%s: timeout waiting for framedone\n",
720				__func__);
721	}
722	pm_runtime_put_sync(dev->dev);
723}
724
725static const struct drm_crtc_funcs tilcdc_crtc_funcs = {
726	.destroy        = tilcdc_crtc_destroy,
727	.set_config     = drm_atomic_helper_set_config,
728	.page_flip      = drm_atomic_helper_page_flip,
729	.reset		= tilcdc_crtc_reset,
730	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
731	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
732	.enable_vblank	= tilcdc_crtc_enable_vblank,
733	.disable_vblank	= tilcdc_crtc_disable_vblank,
734};
735
736int tilcdc_crtc_max_width(struct drm_crtc *crtc)
737{
738	struct drm_device *dev = crtc->dev;
739	struct tilcdc_drm_private *priv = dev->dev_private;
740	int max_width = 0;
741
742	if (priv->rev == 1)
743		max_width = 1024;
744	else if (priv->rev == 2)
745		max_width = 2048;
746
747	return max_width;
748}
749
750static enum drm_mode_status
751tilcdc_crtc_mode_valid(struct drm_crtc *crtc,
752		       const struct drm_display_mode *mode)
753{
754	struct tilcdc_drm_private *priv = crtc->dev->dev_private;
755	unsigned int bandwidth;
756	uint32_t hbp, hfp, hsw, vbp, vfp, vsw;
757
758	/*
759	 * check to see if the width is within the range that
760	 * the LCD Controller physically supports
761	 */
762	if (mode->hdisplay > tilcdc_crtc_max_width(crtc))
763		return MODE_VIRTUAL_X;
764
765	/* width must be multiple of 16 */
766	if (mode->hdisplay & 0xf)
767		return MODE_VIRTUAL_X;
768
769	if (mode->vdisplay > 2048)
770		return MODE_VIRTUAL_Y;
771
772	DBG("Processing mode %dx%d@%d with pixel clock %d",
773		mode->hdisplay, mode->vdisplay,
774		drm_mode_vrefresh(mode), mode->clock);
775
776	hbp = mode->htotal - mode->hsync_end;
777	hfp = mode->hsync_start - mode->hdisplay;
778	hsw = mode->hsync_end - mode->hsync_start;
779	vbp = mode->vtotal - mode->vsync_end;
780	vfp = mode->vsync_start - mode->vdisplay;
781	vsw = mode->vsync_end - mode->vsync_start;
782
783	if ((hbp-1) & ~0x3ff) {
784		DBG("Pruning mode: Horizontal Back Porch out of range");
785		return MODE_HBLANK_WIDE;
786	}
787
788	if ((hfp-1) & ~0x3ff) {
789		DBG("Pruning mode: Horizontal Front Porch out of range");
790		return MODE_HBLANK_WIDE;
791	}
792
793	if ((hsw-1) & ~0x3ff) {
794		DBG("Pruning mode: Horizontal Sync Width out of range");
795		return MODE_HSYNC_WIDE;
796	}
797
798	if (vbp & ~0xff) {
799		DBG("Pruning mode: Vertical Back Porch out of range");
800		return MODE_VBLANK_WIDE;
801	}
802
803	if (vfp & ~0xff) {
804		DBG("Pruning mode: Vertical Front Porch out of range");
805		return MODE_VBLANK_WIDE;
806	}
807
808	if ((vsw-1) & ~0x3f) {
809		DBG("Pruning mode: Vertical Sync Width out of range");
810		return MODE_VSYNC_WIDE;
811	}
812
813	/*
814	 * some devices have a maximum allowed pixel clock
815	 * configured from the DT
816	 */
817	if (mode->clock > priv->max_pixelclock) {
818		DBG("Pruning mode: pixel clock too high");
819		return MODE_CLOCK_HIGH;
820	}
821
822	/*
823	 * some devices further limit the max horizontal resolution
824	 * configured from the DT
825	 */
826	if (mode->hdisplay > priv->max_width)
827		return MODE_BAD_WIDTH;
828
829	/* filter out modes that would require too much memory bandwidth: */
830	bandwidth = mode->hdisplay * mode->vdisplay *
831		drm_mode_vrefresh(mode);
832	if (bandwidth > priv->max_bandwidth) {
833		DBG("Pruning mode: exceeds defined bandwidth limit");
834		return MODE_BAD;
835	}
836
837	return MODE_OK;
838}
839
840static const struct drm_crtc_helper_funcs tilcdc_crtc_helper_funcs = {
841	.mode_valid	= tilcdc_crtc_mode_valid,
842	.mode_fixup	= tilcdc_crtc_mode_fixup,
843	.atomic_check	= tilcdc_crtc_atomic_check,
844	.atomic_enable	= tilcdc_crtc_atomic_enable,
845	.atomic_disable	= tilcdc_crtc_atomic_disable,
846	.atomic_flush	= tilcdc_crtc_atomic_flush,
847};
848
849void tilcdc_crtc_set_panel_info(struct drm_crtc *crtc,
850		const struct tilcdc_panel_info *info)
851{
852	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
853	tilcdc_crtc->info = info;
854}
855
856void tilcdc_crtc_set_simulate_vesa_sync(struct drm_crtc *crtc,
857					bool simulate_vesa_sync)
858{
859	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
860
861	tilcdc_crtc->simulate_vesa_sync = simulate_vesa_sync;
862}
863
864void tilcdc_crtc_update_clk(struct drm_crtc *crtc)
865{
866	struct drm_device *dev = crtc->dev;
867	struct tilcdc_drm_private *priv = dev->dev_private;
868	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
869
870	drm_modeset_lock(&crtc->mutex, NULL);
871	if (tilcdc_crtc->lcd_fck_rate != clk_get_rate(priv->clk)) {
872		if (tilcdc_crtc_is_on(crtc)) {
873			pm_runtime_get_sync(dev->dev);
874			tilcdc_crtc_disable(crtc);
875
876			tilcdc_crtc_set_clk(crtc);
877
878			tilcdc_crtc_enable(crtc);
879			pm_runtime_put_sync(dev->dev);
880		}
881	}
882	drm_modeset_unlock(&crtc->mutex);
883}
884
885#define SYNC_LOST_COUNT_LIMIT 50
886
887irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
888{
889	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
890	struct drm_device *dev = crtc->dev;
891	struct tilcdc_drm_private *priv = dev->dev_private;
892	uint32_t stat, reg;
893
894	stat = tilcdc_read_irqstatus(dev);
895	tilcdc_clear_irqstatus(dev, stat);
896
897	if (stat & LCDC_END_OF_FRAME0) {
898		unsigned long flags;
899		bool skip_event = false;
900		ktime_t now;
901
902		now = ktime_get();
903
904		spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags);
905
906		tilcdc_crtc->last_vblank = now;
907
908		if (tilcdc_crtc->next_fb) {
909			set_scanout(crtc, tilcdc_crtc->next_fb);
910			tilcdc_crtc->next_fb = NULL;
911			skip_event = true;
912		}
913
914		spin_unlock_irqrestore(&tilcdc_crtc->irq_lock, flags);
915
916		drm_crtc_handle_vblank(crtc);
917
918		if (!skip_event) {
919			struct drm_pending_vblank_event *event;
920
921			spin_lock_irqsave(&dev->event_lock, flags);
922
923			event = tilcdc_crtc->event;
924			tilcdc_crtc->event = NULL;
925			if (event)
926				drm_crtc_send_vblank_event(crtc, event);
927
928			spin_unlock_irqrestore(&dev->event_lock, flags);
929		}
930
931		if (tilcdc_crtc->frame_intact)
932			tilcdc_crtc->sync_lost_count = 0;
933		else
934			tilcdc_crtc->frame_intact = true;
935	}
936
937	if (stat & LCDC_FIFO_UNDERFLOW)
938		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underflow",
939				    __func__, stat);
940
941	if (stat & LCDC_PL_LOAD_DONE) {
942		complete(&tilcdc_crtc->palette_loaded);
943		if (priv->rev == 1)
944			tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
945				     LCDC_V1_PL_INT_ENA);
946		else
947			tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
948				     LCDC_V2_PL_INT_ENA);
949	}
950
951	if (stat & LCDC_SYNC_LOST) {
952		dev_err_ratelimited(dev->dev, "%s(0x%08x): Sync lost",
953				    __func__, stat);
954		tilcdc_crtc->frame_intact = false;
955		if (priv->rev == 1) {
956			reg = tilcdc_read(dev, LCDC_RASTER_CTRL_REG);
957			if (reg & LCDC_RASTER_ENABLE) {
958				tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
959					     LCDC_RASTER_ENABLE);
960				tilcdc_set(dev, LCDC_RASTER_CTRL_REG,
961					   LCDC_RASTER_ENABLE);
962			}
963		} else {
964			if (tilcdc_crtc->sync_lost_count++ >
965			    SYNC_LOST_COUNT_LIMIT) {
966				dev_err(dev->dev,
967					"%s(0x%08x): Sync lost flood detected, recovering",
968					__func__, stat);
969				queue_work(system_wq,
970					   &tilcdc_crtc->recover_work);
971				tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
972					     LCDC_SYNC_LOST);
973				tilcdc_crtc->sync_lost_count = 0;
974			}
975		}
976	}
977
978	if (stat & LCDC_FRAME_DONE) {
979		tilcdc_crtc->frame_done = true;
980		wake_up(&tilcdc_crtc->frame_done_wq);
981		/* rev 1 lcdc appears to hang if irq is not disbaled here */
982		if (priv->rev == 1)
983			tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
984				     LCDC_V1_FRAME_DONE_INT_ENA);
985	}
986
987	/* For revision 2 only */
988	if (priv->rev == 2) {
989		/* Indicate to LCDC that the interrupt service routine has
990		 * completed, see 13.3.6.1.6 in AM335x TRM.
991		 */
992		tilcdc_write(dev, LCDC_END_OF_INT_IND_REG, 0);
993	}
994
995	return IRQ_HANDLED;
996}
997
998int tilcdc_crtc_create(struct drm_device *dev)
999{
1000	struct tilcdc_drm_private *priv = dev->dev_private;
1001	struct tilcdc_crtc *tilcdc_crtc;
1002	struct drm_crtc *crtc;
1003	int ret;
1004
1005	tilcdc_crtc = devm_kzalloc(dev->dev, sizeof(*tilcdc_crtc), GFP_KERNEL);
1006	if (!tilcdc_crtc)
1007		return -ENOMEM;
1008
1009	init_completion(&tilcdc_crtc->palette_loaded);
1010	tilcdc_crtc->palette_base = dmam_alloc_coherent(dev->dev,
1011					TILCDC_PALETTE_SIZE,
1012					&tilcdc_crtc->palette_dma_handle,
1013					GFP_KERNEL | __GFP_ZERO);
1014	if (!tilcdc_crtc->palette_base)
1015		return -ENOMEM;
1016	*tilcdc_crtc->palette_base = TILCDC_PALETTE_FIRST_ENTRY;
1017
1018	crtc = &tilcdc_crtc->base;
1019
1020	ret = tilcdc_plane_init(dev, &tilcdc_crtc->primary);
1021	if (ret < 0)
1022		goto fail;
1023
1024	mutex_init(&tilcdc_crtc->enable_lock);
1025
1026	init_waitqueue_head(&tilcdc_crtc->frame_done_wq);
1027
1028	spin_lock_init(&tilcdc_crtc->irq_lock);
1029	INIT_WORK(&tilcdc_crtc->recover_work, tilcdc_crtc_recover_work);
1030
1031	ret = drm_crtc_init_with_planes(dev, crtc,
1032					&tilcdc_crtc->primary,
1033					NULL,
1034					&tilcdc_crtc_funcs,
1035					"tilcdc crtc");
1036	if (ret < 0)
1037		goto fail;
1038
1039	drm_crtc_helper_add(crtc, &tilcdc_crtc_helper_funcs);
1040
1041	if (priv->is_componentized) {
1042		crtc->port = of_graph_get_port_by_id(dev->dev->of_node, 0);
1043		if (!crtc->port) { /* This should never happen */
1044			dev_err(dev->dev, "Port node not found in %pOF\n",
1045				dev->dev->of_node);
1046			ret = -EINVAL;
1047			goto fail;
1048		}
1049	}
1050
1051	priv->crtc = crtc;
1052	return 0;
1053
1054fail:
1055	tilcdc_crtc_destroy(crtc);
1056	return ret;
1057}
1058