1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 Traphandler
4  * Copyright (C) 2014 Free Electrons
5  *
6  * Author: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
7  * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/mfd/atmel-hlcdc.h>
12 #include <linux/pinctrl/consumer.h>
13 #include <linux/pm.h>
14 #include <linux/pm_runtime.h>
15 
16 #include <video/videomode.h>
17 
18 #include <drm/drm_atomic.h>
19 #include <drm/drm_atomic_helper.h>
20 #include <drm/drm_crtc.h>
21 #include <drm/drm_modeset_helper_vtables.h>
22 #include <drm/drm_probe_helper.h>
23 #include <drm/drm_vblank.h>
24 
25 #include "atmel_hlcdc_dc.h"
26 
27 /**
28  * Atmel HLCDC CRTC state structure
29  *
30  * @base: base CRTC state
31  * @output_mode: RGBXXX output mode
32  */
33 struct atmel_hlcdc_crtc_state {
34 	struct drm_crtc_state base;
35 	unsigned int output_mode;
36 };
37 
38 static inline struct atmel_hlcdc_crtc_state *
39 drm_crtc_state_to_atmel_hlcdc_crtc_state(struct drm_crtc_state *state)
40 {
41 	return container_of(state, struct atmel_hlcdc_crtc_state, base);
42 }
43 
44 /**
45  * Atmel HLCDC CRTC structure
46  *
47  * @base: base DRM CRTC structure
48  * @hlcdc: pointer to the atmel_hlcdc structure provided by the MFD device
49  * @event: pointer to the current page flip event
50  * @id: CRTC id (returned by drm_crtc_index)
51  */
52 struct atmel_hlcdc_crtc {
53 	struct drm_crtc base;
54 	struct atmel_hlcdc_dc *dc;
55 	struct drm_pending_vblank_event *event;
56 	int id;
57 };
58 
59 static inline struct atmel_hlcdc_crtc *
60 drm_crtc_to_atmel_hlcdc_crtc(struct drm_crtc *crtc)
61 {
62 	return container_of(crtc, struct atmel_hlcdc_crtc, base);
63 }
64 
65 static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
66 {
67 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
68 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
69 	struct drm_display_mode *adj = &c->state->adjusted_mode;
70 	struct atmel_hlcdc_crtc_state *state;
71 	unsigned long mode_rate;
72 	struct videomode vm;
73 	unsigned long prate;
74 	unsigned int mask = ATMEL_HLCDC_CLKDIV_MASK | ATMEL_HLCDC_CLKPOL;
75 	unsigned int cfg = 0;
76 	int div, ret;
77 
78 	ret = clk_prepare_enable(crtc->dc->hlcdc->sys_clk);
79 	if (ret)
80 		return;
81 
82 	vm.vfront_porch = adj->crtc_vsync_start - adj->crtc_vdisplay;
83 	vm.vback_porch = adj->crtc_vtotal - adj->crtc_vsync_end;
84 	vm.vsync_len = adj->crtc_vsync_end - adj->crtc_vsync_start;
85 	vm.hfront_porch = adj->crtc_hsync_start - adj->crtc_hdisplay;
86 	vm.hback_porch = adj->crtc_htotal - adj->crtc_hsync_end;
87 	vm.hsync_len = adj->crtc_hsync_end - adj->crtc_hsync_start;
88 
89 	regmap_write(regmap, ATMEL_HLCDC_CFG(1),
90 		     (vm.hsync_len - 1) | ((vm.vsync_len - 1) << 16));
91 
92 	regmap_write(regmap, ATMEL_HLCDC_CFG(2),
93 		     (vm.vfront_porch - 1) | (vm.vback_porch << 16));
94 
95 	regmap_write(regmap, ATMEL_HLCDC_CFG(3),
96 		     (vm.hfront_porch - 1) | ((vm.hback_porch - 1) << 16));
97 
98 	regmap_write(regmap, ATMEL_HLCDC_CFG(4),
99 		     (adj->crtc_hdisplay - 1) |
100 		     ((adj->crtc_vdisplay - 1) << 16));
101 
102 	prate = clk_get_rate(crtc->dc->hlcdc->sys_clk);
103 	mode_rate = adj->crtc_clock * 1000;
104 	if (!crtc->dc->desc->fixed_clksrc) {
105 		prate *= 2;
106 		cfg |= ATMEL_HLCDC_CLKSEL;
107 		mask |= ATMEL_HLCDC_CLKSEL;
108 	}
109 
110 	div = DIV_ROUND_UP(prate, mode_rate);
111 	if (div < 2) {
112 		div = 2;
113 	} else if (ATMEL_HLCDC_CLKDIV(div) & ~ATMEL_HLCDC_CLKDIV_MASK) {
114 		/* The divider ended up too big, try a lower base rate. */
115 		cfg &= ~ATMEL_HLCDC_CLKSEL;
116 		prate /= 2;
117 		div = DIV_ROUND_UP(prate, mode_rate);
118 		if (ATMEL_HLCDC_CLKDIV(div) & ~ATMEL_HLCDC_CLKDIV_MASK)
119 			div = ATMEL_HLCDC_CLKDIV_MASK;
120 	} else {
121 		int div_low = prate / mode_rate;
122 
123 		if (div_low >= 2 &&
124 		    (10 * (prate / div_low - mode_rate) <
125 		     (mode_rate - prate / div)))
126 			/*
127 			 * At least 10 times better when using a higher
128 			 * frequency than requested, instead of a lower.
129 			 * So, go with that.
130 			 */
131 			div = div_low;
132 	}
133 
134 	cfg |= ATMEL_HLCDC_CLKDIV(div);
135 
136 	regmap_update_bits(regmap, ATMEL_HLCDC_CFG(0), mask, cfg);
137 
138 	state = drm_crtc_state_to_atmel_hlcdc_crtc_state(c->state);
139 	cfg = state->output_mode << 8;
140 
141 	if (adj->flags & DRM_MODE_FLAG_NVSYNC)
142 		cfg |= ATMEL_HLCDC_VSPOL;
143 
144 	if (adj->flags & DRM_MODE_FLAG_NHSYNC)
145 		cfg |= ATMEL_HLCDC_HSPOL;
146 
147 	regmap_update_bits(regmap, ATMEL_HLCDC_CFG(5),
148 			   ATMEL_HLCDC_HSPOL | ATMEL_HLCDC_VSPOL |
149 			   ATMEL_HLCDC_VSPDLYS | ATMEL_HLCDC_VSPDLYE |
150 			   ATMEL_HLCDC_DISPPOL | ATMEL_HLCDC_DISPDLY |
151 			   ATMEL_HLCDC_VSPSU | ATMEL_HLCDC_VSPHO |
152 			   ATMEL_HLCDC_GUARDTIME_MASK | ATMEL_HLCDC_MODE_MASK,
153 			   cfg);
154 
155 	clk_disable_unprepare(crtc->dc->hlcdc->sys_clk);
156 }
157 
158 static enum drm_mode_status
159 atmel_hlcdc_crtc_mode_valid(struct drm_crtc *c,
160 			    const struct drm_display_mode *mode)
161 {
162 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
163 
164 	return atmel_hlcdc_dc_mode_valid(crtc->dc, mode);
165 }
166 
167 static void atmel_hlcdc_crtc_atomic_disable(struct drm_crtc *c,
168 					    struct drm_crtc_state *old_state)
169 {
170 	struct drm_device *dev = c->dev;
171 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
172 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
173 	unsigned int status;
174 
175 	drm_crtc_vblank_off(c);
176 
177 	pm_runtime_get_sync(dev->dev);
178 
179 	regmap_write(regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_DISP);
180 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
181 	       (status & ATMEL_HLCDC_DISP))
182 		cpu_relax();
183 
184 	regmap_write(regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_SYNC);
185 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
186 	       (status & ATMEL_HLCDC_SYNC))
187 		cpu_relax();
188 
189 	regmap_write(regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_PIXEL_CLK);
190 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
191 	       (status & ATMEL_HLCDC_PIXEL_CLK))
192 		cpu_relax();
193 
194 	clk_disable_unprepare(crtc->dc->hlcdc->sys_clk);
195 	pinctrl_pm_select_sleep_state(dev->dev);
196 
197 	pm_runtime_allow(dev->dev);
198 
199 	pm_runtime_put_sync(dev->dev);
200 }
201 
202 static void atmel_hlcdc_crtc_atomic_enable(struct drm_crtc *c,
203 					   struct drm_crtc_state *old_state)
204 {
205 	struct drm_device *dev = c->dev;
206 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
207 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
208 	unsigned int status;
209 
210 	pm_runtime_get_sync(dev->dev);
211 
212 	pm_runtime_forbid(dev->dev);
213 
214 	pinctrl_pm_select_default_state(dev->dev);
215 	clk_prepare_enable(crtc->dc->hlcdc->sys_clk);
216 
217 	regmap_write(regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_PIXEL_CLK);
218 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
219 	       !(status & ATMEL_HLCDC_PIXEL_CLK))
220 		cpu_relax();
221 
222 
223 	regmap_write(regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_SYNC);
224 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
225 	       !(status & ATMEL_HLCDC_SYNC))
226 		cpu_relax();
227 
228 	regmap_write(regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_DISP);
229 	while (!regmap_read(regmap, ATMEL_HLCDC_SR, &status) &&
230 	       !(status & ATMEL_HLCDC_DISP))
231 		cpu_relax();
232 
233 	pm_runtime_put_sync(dev->dev);
234 
235 	drm_crtc_vblank_on(c);
236 }
237 
238 #define ATMEL_HLCDC_RGB444_OUTPUT	BIT(0)
239 #define ATMEL_HLCDC_RGB565_OUTPUT	BIT(1)
240 #define ATMEL_HLCDC_RGB666_OUTPUT	BIT(2)
241 #define ATMEL_HLCDC_RGB888_OUTPUT	BIT(3)
242 #define ATMEL_HLCDC_OUTPUT_MODE_MASK	GENMASK(3, 0)
243 
244 static int atmel_hlcdc_connector_output_mode(struct drm_connector_state *state)
245 {
246 	struct drm_connector *connector = state->connector;
247 	struct drm_display_info *info = &connector->display_info;
248 	struct drm_encoder *encoder;
249 	unsigned int supported_fmts = 0;
250 	int j;
251 
252 	encoder = state->best_encoder;
253 	if (!encoder)
254 		encoder = connector->encoder;
255 
256 	switch (atmel_hlcdc_encoder_get_bus_fmt(encoder)) {
257 	case 0:
258 		break;
259 	case MEDIA_BUS_FMT_RGB444_1X12:
260 		return ATMEL_HLCDC_RGB444_OUTPUT;
261 	case MEDIA_BUS_FMT_RGB565_1X16:
262 		return ATMEL_HLCDC_RGB565_OUTPUT;
263 	case MEDIA_BUS_FMT_RGB666_1X18:
264 		return ATMEL_HLCDC_RGB666_OUTPUT;
265 	case MEDIA_BUS_FMT_RGB888_1X24:
266 		return ATMEL_HLCDC_RGB888_OUTPUT;
267 	default:
268 		return -EINVAL;
269 	}
270 
271 	for (j = 0; j < info->num_bus_formats; j++) {
272 		switch (info->bus_formats[j]) {
273 		case MEDIA_BUS_FMT_RGB444_1X12:
274 			supported_fmts |= ATMEL_HLCDC_RGB444_OUTPUT;
275 			break;
276 		case MEDIA_BUS_FMT_RGB565_1X16:
277 			supported_fmts |= ATMEL_HLCDC_RGB565_OUTPUT;
278 			break;
279 		case MEDIA_BUS_FMT_RGB666_1X18:
280 			supported_fmts |= ATMEL_HLCDC_RGB666_OUTPUT;
281 			break;
282 		case MEDIA_BUS_FMT_RGB888_1X24:
283 			supported_fmts |= ATMEL_HLCDC_RGB888_OUTPUT;
284 			break;
285 		default:
286 			break;
287 		}
288 	}
289 
290 	return supported_fmts;
291 }
292 
293 static int atmel_hlcdc_crtc_select_output_mode(struct drm_crtc_state *state)
294 {
295 	unsigned int output_fmts = ATMEL_HLCDC_OUTPUT_MODE_MASK;
296 	struct atmel_hlcdc_crtc_state *hstate;
297 	struct drm_connector_state *cstate;
298 	struct drm_connector *connector;
299 	struct atmel_hlcdc_crtc *crtc;
300 	int i;
301 
302 	crtc = drm_crtc_to_atmel_hlcdc_crtc(state->crtc);
303 
304 	for_each_new_connector_in_state(state->state, connector, cstate, i) {
305 		unsigned int supported_fmts = 0;
306 
307 		if (!cstate->crtc)
308 			continue;
309 
310 		supported_fmts = atmel_hlcdc_connector_output_mode(cstate);
311 
312 		if (crtc->dc->desc->conflicting_output_formats)
313 			output_fmts &= supported_fmts;
314 		else
315 			output_fmts |= supported_fmts;
316 	}
317 
318 	if (!output_fmts)
319 		return -EINVAL;
320 
321 	hstate = drm_crtc_state_to_atmel_hlcdc_crtc_state(state);
322 	hstate->output_mode = fls(output_fmts) - 1;
323 
324 	return 0;
325 }
326 
327 static int atmel_hlcdc_crtc_atomic_check(struct drm_crtc *c,
328 					 struct drm_crtc_state *s)
329 {
330 	int ret;
331 
332 	ret = atmel_hlcdc_crtc_select_output_mode(s);
333 	if (ret)
334 		return ret;
335 
336 	ret = atmel_hlcdc_plane_prepare_disc_area(s);
337 	if (ret)
338 		return ret;
339 
340 	return atmel_hlcdc_plane_prepare_ahb_routing(s);
341 }
342 
343 static void atmel_hlcdc_crtc_atomic_begin(struct drm_crtc *c,
344 					  struct drm_crtc_state *old_s)
345 {
346 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
347 
348 	if (c->state->event) {
349 		c->state->event->pipe = drm_crtc_index(c);
350 
351 		WARN_ON(drm_crtc_vblank_get(c) != 0);
352 
353 		crtc->event = c->state->event;
354 		c->state->event = NULL;
355 	}
356 }
357 
358 static void atmel_hlcdc_crtc_atomic_flush(struct drm_crtc *crtc,
359 					  struct drm_crtc_state *old_s)
360 {
361 	/* TODO: write common plane control register if available */
362 }
363 
364 static const struct drm_crtc_helper_funcs lcdc_crtc_helper_funcs = {
365 	.mode_valid = atmel_hlcdc_crtc_mode_valid,
366 	.mode_set_nofb = atmel_hlcdc_crtc_mode_set_nofb,
367 	.atomic_check = atmel_hlcdc_crtc_atomic_check,
368 	.atomic_begin = atmel_hlcdc_crtc_atomic_begin,
369 	.atomic_flush = atmel_hlcdc_crtc_atomic_flush,
370 	.atomic_enable = atmel_hlcdc_crtc_atomic_enable,
371 	.atomic_disable = atmel_hlcdc_crtc_atomic_disable,
372 };
373 
374 static void atmel_hlcdc_crtc_destroy(struct drm_crtc *c)
375 {
376 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
377 
378 	drm_crtc_cleanup(c);
379 	kfree(crtc);
380 }
381 
382 static void atmel_hlcdc_crtc_finish_page_flip(struct atmel_hlcdc_crtc *crtc)
383 {
384 	struct drm_device *dev = crtc->base.dev;
385 	unsigned long flags;
386 
387 	spin_lock_irqsave(&dev->event_lock, flags);
388 	if (crtc->event) {
389 		drm_crtc_send_vblank_event(&crtc->base, crtc->event);
390 		drm_crtc_vblank_put(&crtc->base);
391 		crtc->event = NULL;
392 	}
393 	spin_unlock_irqrestore(&dev->event_lock, flags);
394 }
395 
396 void atmel_hlcdc_crtc_irq(struct drm_crtc *c)
397 {
398 	drm_crtc_handle_vblank(c);
399 	atmel_hlcdc_crtc_finish_page_flip(drm_crtc_to_atmel_hlcdc_crtc(c));
400 }
401 
402 static void atmel_hlcdc_crtc_reset(struct drm_crtc *crtc)
403 {
404 	struct atmel_hlcdc_crtc_state *state;
405 
406 	if (crtc->state) {
407 		__drm_atomic_helper_crtc_destroy_state(crtc->state);
408 		state = drm_crtc_state_to_atmel_hlcdc_crtc_state(crtc->state);
409 		kfree(state);
410 		crtc->state = NULL;
411 	}
412 
413 	state = kzalloc(sizeof(*state), GFP_KERNEL);
414 	if (state)
415 		__drm_atomic_helper_crtc_reset(crtc, &state->base);
416 }
417 
418 static struct drm_crtc_state *
419 atmel_hlcdc_crtc_duplicate_state(struct drm_crtc *crtc)
420 {
421 	struct atmel_hlcdc_crtc_state *state, *cur;
422 
423 	if (WARN_ON(!crtc->state))
424 		return NULL;
425 
426 	state = kmalloc(sizeof(*state), GFP_KERNEL);
427 	if (!state)
428 		return NULL;
429 	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
430 
431 	cur = drm_crtc_state_to_atmel_hlcdc_crtc_state(crtc->state);
432 	state->output_mode = cur->output_mode;
433 
434 	return &state->base;
435 }
436 
437 static void atmel_hlcdc_crtc_destroy_state(struct drm_crtc *crtc,
438 					   struct drm_crtc_state *s)
439 {
440 	struct atmel_hlcdc_crtc_state *state;
441 
442 	state = drm_crtc_state_to_atmel_hlcdc_crtc_state(s);
443 	__drm_atomic_helper_crtc_destroy_state(s);
444 	kfree(state);
445 }
446 
447 static int atmel_hlcdc_crtc_enable_vblank(struct drm_crtc *c)
448 {
449 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
450 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
451 
452 	/* Enable SOF (Start Of Frame) interrupt for vblank counting */
453 	regmap_write(regmap, ATMEL_HLCDC_IER, ATMEL_HLCDC_SOF);
454 
455 	return 0;
456 }
457 
458 static void atmel_hlcdc_crtc_disable_vblank(struct drm_crtc *c)
459 {
460 	struct atmel_hlcdc_crtc *crtc = drm_crtc_to_atmel_hlcdc_crtc(c);
461 	struct regmap *regmap = crtc->dc->hlcdc->regmap;
462 
463 	regmap_write(regmap, ATMEL_HLCDC_IDR, ATMEL_HLCDC_SOF);
464 }
465 
466 static const struct drm_crtc_funcs atmel_hlcdc_crtc_funcs = {
467 	.page_flip = drm_atomic_helper_page_flip,
468 	.set_config = drm_atomic_helper_set_config,
469 	.destroy = atmel_hlcdc_crtc_destroy,
470 	.reset = atmel_hlcdc_crtc_reset,
471 	.atomic_duplicate_state =  atmel_hlcdc_crtc_duplicate_state,
472 	.atomic_destroy_state = atmel_hlcdc_crtc_destroy_state,
473 	.enable_vblank = atmel_hlcdc_crtc_enable_vblank,
474 	.disable_vblank = atmel_hlcdc_crtc_disable_vblank,
475 	.gamma_set = drm_atomic_helper_legacy_gamma_set,
476 };
477 
478 int atmel_hlcdc_crtc_create(struct drm_device *dev)
479 {
480 	struct atmel_hlcdc_plane *primary = NULL, *cursor = NULL;
481 	struct atmel_hlcdc_dc *dc = dev->dev_private;
482 	struct atmel_hlcdc_crtc *crtc;
483 	int ret;
484 	int i;
485 
486 	crtc = kzalloc(sizeof(*crtc), GFP_KERNEL);
487 	if (!crtc)
488 		return -ENOMEM;
489 
490 	crtc->dc = dc;
491 
492 	for (i = 0; i < ATMEL_HLCDC_MAX_LAYERS; i++) {
493 		if (!dc->layers[i])
494 			continue;
495 
496 		switch (dc->layers[i]->desc->type) {
497 		case ATMEL_HLCDC_BASE_LAYER:
498 			primary = atmel_hlcdc_layer_to_plane(dc->layers[i]);
499 			break;
500 
501 		case ATMEL_HLCDC_CURSOR_LAYER:
502 			cursor = atmel_hlcdc_layer_to_plane(dc->layers[i]);
503 			break;
504 
505 		default:
506 			break;
507 		}
508 	}
509 
510 	ret = drm_crtc_init_with_planes(dev, &crtc->base, &primary->base,
511 					&cursor->base, &atmel_hlcdc_crtc_funcs,
512 					NULL);
513 	if (ret < 0)
514 		goto fail;
515 
516 	crtc->id = drm_crtc_index(&crtc->base);
517 
518 	for (i = 0; i < ATMEL_HLCDC_MAX_LAYERS; i++) {
519 		struct atmel_hlcdc_plane *overlay;
520 
521 		if (dc->layers[i] &&
522 		    dc->layers[i]->desc->type == ATMEL_HLCDC_OVERLAY_LAYER) {
523 			overlay = atmel_hlcdc_layer_to_plane(dc->layers[i]);
524 			overlay->base.possible_crtcs = 1 << crtc->id;
525 		}
526 	}
527 
528 	drm_crtc_helper_add(&crtc->base, &lcdc_crtc_helper_funcs);
529 
530 	drm_mode_crtc_set_gamma_size(&crtc->base, ATMEL_HLCDC_CLUT_SIZE);
531 	drm_crtc_enable_color_mgmt(&crtc->base, 0, false,
532 				   ATMEL_HLCDC_CLUT_SIZE);
533 
534 	dc->crtc = &crtc->base;
535 
536 	return 0;
537 
538 fail:
539 	atmel_hlcdc_crtc_destroy(&crtc->base);
540 	return ret;
541 }
542