summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/tiny/simpledrm.c
blob: 768242a78e2bf476c220dd024e809af29d6d1b13 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
// SPDX-License-Identifier: GPL-2.0-only

#include <linux/clk.h>
#include <linux/of_clk.h>
#include <linux/minmax.h>
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>

#include <drm/drm_aperture.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_connector.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_format_helper.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_simple_kms_helper.h>

#define DRIVER_NAME	"simpledrm"
#define DRIVER_DESC	"DRM driver for simple-framebuffer platform devices"
#define DRIVER_DATE	"20200625"
#define DRIVER_MAJOR	1
#define DRIVER_MINOR	0

/*
 * Assume a monitor resolution of 96 dpi to
 * get a somewhat reasonable screen size.
 */
#define RES_MM(d)	\
	(((d) * 254ul) / (96ul * 10ul))

#define SIMPLEDRM_MODE(hd, vd)	\
	DRM_SIMPLE_MODE(hd, vd, RES_MM(hd), RES_MM(vd))

/*
 * Helpers for simplefb
 */

static int
simplefb_get_validated_int(struct drm_device *dev, const char *name,
			   uint32_t value)
{
	if (value > INT_MAX) {
		drm_err(dev, "simplefb: invalid framebuffer %s of %u\n",
			name, value);
		return -EINVAL;
	}
	return (int)value;
}

static int
simplefb_get_validated_int0(struct drm_device *dev, const char *name,
			    uint32_t value)
{
	if (!value) {
		drm_err(dev, "simplefb: invalid framebuffer %s of %u\n",
			name, value);
		return -EINVAL;
	}
	return simplefb_get_validated_int(dev, name, value);
}

static const struct drm_format_info *
simplefb_get_validated_format(struct drm_device *dev, const char *format_name)
{
	static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
	const struct simplefb_format *fmt = formats;
	const struct simplefb_format *end = fmt + ARRAY_SIZE(formats);
	const struct drm_format_info *info;

	if (!format_name) {
		drm_err(dev, "simplefb: missing framebuffer format\n");
		return ERR_PTR(-EINVAL);
	}

	while (fmt < end) {
		if (!strcmp(format_name, fmt->name)) {
			info = drm_format_info(fmt->fourcc);
			if (!info)
				return ERR_PTR(-EINVAL);
			return info;
		}
		++fmt;
	}

	drm_err(dev, "simplefb: unknown framebuffer format %s\n",
		format_name);

	return ERR_PTR(-EINVAL);
}

static int
simplefb_get_width_pd(struct drm_device *dev,
		      const struct simplefb_platform_data *pd)
{
	return simplefb_get_validated_int0(dev, "width", pd->width);
}

static int
simplefb_get_height_pd(struct drm_device *dev,
		       const struct simplefb_platform_data *pd)
{
	return simplefb_get_validated_int0(dev, "height", pd->height);
}

static int
simplefb_get_stride_pd(struct drm_device *dev,
		       const struct simplefb_platform_data *pd)
{
	return simplefb_get_validated_int(dev, "stride", pd->stride);
}

static const struct drm_format_info *
simplefb_get_format_pd(struct drm_device *dev,
		       const struct simplefb_platform_data *pd)
{
	return simplefb_get_validated_format(dev, pd->format);
}

static int
simplefb_read_u32_of(struct drm_device *dev, struct device_node *of_node,
		     const char *name, u32 *value)
{
	int ret = of_property_read_u32(of_node, name, value);

	if (ret)
		drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
			name, ret);
	return ret;
}

static int
simplefb_read_string_of(struct drm_device *dev, struct device_node *of_node,
			const char *name, const char **value)
{
	int ret = of_property_read_string(of_node, name, value);

	if (ret)
		drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
			name, ret);
	return ret;
}

static int
simplefb_get_width_of(struct drm_device *dev, struct device_node *of_node)
{
	u32 width;
	int ret = simplefb_read_u32_of(dev, of_node, "width", &width);

	if (ret)
		return ret;
	return simplefb_get_validated_int0(dev, "width", width);
}

static int
simplefb_get_height_of(struct drm_device *dev, struct device_node *of_node)
{
	u32 height;
	int ret = simplefb_read_u32_of(dev, of_node, "height", &height);

	if (ret)
		return ret;
	return simplefb_get_validated_int0(dev, "height", height);
}

static int
simplefb_get_stride_of(struct drm_device *dev, struct device_node *of_node)
{
	u32 stride;
	int ret = simplefb_read_u32_of(dev, of_node, "stride", &stride);

	if (ret)
		return ret;
	return simplefb_get_validated_int(dev, "stride", stride);
}

static const struct drm_format_info *
simplefb_get_format_of(struct drm_device *dev, struct device_node *of_node)
{
	const char *format;
	int ret = simplefb_read_string_of(dev, of_node, "format", &format);

	if (ret)
		return ERR_PTR(ret);
	return simplefb_get_validated_format(dev, format);
}

/*
 * Simple Framebuffer device
 */

struct simpledrm_device {
	struct drm_device dev;
	struct platform_device *pdev;

	/* clocks */
#if defined CONFIG_OF && defined CONFIG_COMMON_CLK
	unsigned int clk_count;
	struct clk **clks;
#endif
	/* regulators */
#if defined CONFIG_OF && defined CONFIG_REGULATOR
	unsigned int regulator_count;
	struct regulator **regulators;
#endif

	/* simplefb settings */
	struct drm_display_mode mode;
	const struct drm_format_info *format;
	unsigned int pitch;

	/* memory management */
	struct resource *mem;
	void __iomem *screen_base;

	/* modesetting */
	uint32_t formats[8];
	size_t nformats;
	struct drm_connector connector;
	struct drm_simple_display_pipe pipe;
};

static struct simpledrm_device *simpledrm_device_of_dev(struct drm_device *dev)
{
	return container_of(dev, struct simpledrm_device, dev);
}

/*
 * Hardware
 */

#if defined CONFIG_OF && defined CONFIG_COMMON_CLK
/*
 * Clock handling code.
 *
 * Here we handle the clocks property of our "simple-framebuffer" dt node.
 * This is necessary so that we can make sure that any clocks needed by
 * the display engine that the bootloader set up for us (and for which it
 * provided a simplefb dt node), stay up, for the life of the simplefb
 * driver.
 *
 * When the driver unloads, we cleanly disable, and then release the clocks.
 *
 * We only complain about errors here, no action is taken as the most likely
 * error can only happen due to a mismatch between the bootloader which set
 * up simplefb, and the clock definitions in the device tree. Chances are
 * that there are no adverse effects, and if there are, a clean teardown of
 * the fb probe will not help us much either. So just complain and carry on,
 * and hope that the user actually gets a working fb at the end of things.
 */

static void simpledrm_device_release_clocks(void *res)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(res);
	unsigned int i;

	for (i = 0; i < sdev->clk_count; ++i) {
		if (sdev->clks[i]) {
			clk_disable_unprepare(sdev->clks[i]);
			clk_put(sdev->clks[i]);
		}
	}
}

static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
{
	struct drm_device *dev = &sdev->dev;
	struct platform_device *pdev = sdev->pdev;
	struct device_node *of_node = pdev->dev.of_node;
	struct clk *clock;
	unsigned int i;
	int ret;

	if (dev_get_platdata(&pdev->dev) || !of_node)
		return 0;

	sdev->clk_count = of_clk_get_parent_count(of_node);
	if (!sdev->clk_count)
		return 0;

	sdev->clks = drmm_kzalloc(dev, sdev->clk_count * sizeof(sdev->clks[0]),
				  GFP_KERNEL);
	if (!sdev->clks)
		return -ENOMEM;

	for (i = 0; i < sdev->clk_count; ++i) {
		clock = of_clk_get(of_node, i);
		if (IS_ERR(clock)) {
			ret = PTR_ERR(clock);
			if (ret == -EPROBE_DEFER)
				goto err;
			drm_err(dev, "clock %u not found: %d\n", i, ret);
			continue;
		}
		ret = clk_prepare_enable(clock);
		if (ret) {
			drm_err(dev, "failed to enable clock %u: %d\n",
				i, ret);
			clk_put(clock);
			continue;
		}
		sdev->clks[i] = clock;
	}

	return devm_add_action_or_reset(&pdev->dev,
					simpledrm_device_release_clocks,
					sdev);

err:
	while (i) {
		--i;
		if (sdev->clks[i]) {
			clk_disable_unprepare(sdev->clks[i]);
			clk_put(sdev->clks[i]);
		}
	}
	return ret;
}
#else
static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
{
	return 0;
}
#endif

#if defined CONFIG_OF && defined CONFIG_REGULATOR

#define SUPPLY_SUFFIX "-supply"

/*
 * Regulator handling code.
 *
 * Here we handle the num-supplies and vin*-supply properties of our
 * "simple-framebuffer" dt node. This is necessary so that we can make sure
 * that any regulators needed by the display hardware that the bootloader
 * set up for us (and for which it provided a simplefb dt node), stay up,
 * for the life of the simplefb driver.
 *
 * When the driver unloads, we cleanly disable, and then release the
 * regulators.
 *
 * We only complain about errors here, no action is taken as the most likely
 * error can only happen due to a mismatch between the bootloader which set
 * up simplefb, and the regulator definitions in the device tree. Chances are
 * that there are no adverse effects, and if there are, a clean teardown of
 * the fb probe will not help us much either. So just complain and carry on,
 * and hope that the user actually gets a working fb at the end of things.
 */

static void simpledrm_device_release_regulators(void *res)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(res);
	unsigned int i;

	for (i = 0; i < sdev->regulator_count; ++i) {
		if (sdev->regulators[i]) {
			regulator_disable(sdev->regulators[i]);
			regulator_put(sdev->regulators[i]);
		}
	}
}

static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
{
	struct drm_device *dev = &sdev->dev;
	struct platform_device *pdev = sdev->pdev;
	struct device_node *of_node = pdev->dev.of_node;
	struct property *prop;
	struct regulator *regulator;
	const char *p;
	unsigned int count = 0, i = 0;
	int ret;

	if (dev_get_platdata(&pdev->dev) || !of_node)
		return 0;

	/* Count the number of regulator supplies */
	for_each_property_of_node(of_node, prop) {
		p = strstr(prop->name, SUPPLY_SUFFIX);
		if (p && p != prop->name)
			++count;
	}

	if (!count)
		return 0;

	sdev->regulators = drmm_kzalloc(dev,
					count * sizeof(sdev->regulators[0]),
					GFP_KERNEL);
	if (!sdev->regulators)
		return -ENOMEM;

	for_each_property_of_node(of_node, prop) {
		char name[32]; /* 32 is max size of property name */
		size_t len;

		p = strstr(prop->name, SUPPLY_SUFFIX);
		if (!p || p == prop->name)
			continue;
		len = strlen(prop->name) - strlen(SUPPLY_SUFFIX) + 1;
		strscpy(name, prop->name, min(sizeof(name), len));

		regulator = regulator_get_optional(&pdev->dev, name);
		if (IS_ERR(regulator)) {
			ret = PTR_ERR(regulator);
			if (ret == -EPROBE_DEFER)
				goto err;
			drm_err(dev, "regulator %s not found: %d\n",
				name, ret);
			continue;
		}

		ret = regulator_enable(regulator);
		if (ret) {
			drm_err(dev, "failed to enable regulator %u: %d\n",
				i, ret);
			regulator_put(regulator);
			continue;
		}

		sdev->regulators[i++] = regulator;
	}
	sdev->regulator_count = i;

	return devm_add_action_or_reset(&pdev->dev,
					simpledrm_device_release_regulators,
					sdev);

err:
	while (i) {
		--i;
		if (sdev->regulators[i]) {
			regulator_disable(sdev->regulators[i]);
			regulator_put(sdev->regulators[i]);
		}
	}
	return ret;
}
#else
static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
{
	return 0;
}
#endif

/*
 *  Simplefb settings
 */

static struct drm_display_mode simpledrm_mode(unsigned int width,
					      unsigned int height)
{
	struct drm_display_mode mode = { SIMPLEDRM_MODE(width, height) };

	mode.clock = mode.hdisplay * mode.vdisplay * 60 / 1000 /* kHz */;
	drm_mode_set_name(&mode);

	return mode;
}

static int simpledrm_device_init_fb(struct simpledrm_device *sdev)
{
	int width, height, stride;
	const struct drm_format_info *format;
	struct drm_device *dev = &sdev->dev;
	struct platform_device *pdev = sdev->pdev;
	const struct simplefb_platform_data *pd = dev_get_platdata(&pdev->dev);
	struct device_node *of_node = pdev->dev.of_node;

	if (pd) {
		width = simplefb_get_width_pd(dev, pd);
		if (width < 0)
			return width;
		height = simplefb_get_height_pd(dev, pd);
		if (height < 0)
			return height;
		stride = simplefb_get_stride_pd(dev, pd);
		if (stride < 0)
			return stride;
		format = simplefb_get_format_pd(dev, pd);
		if (IS_ERR(format))
			return PTR_ERR(format);
	} else if (of_node) {
		width = simplefb_get_width_of(dev, of_node);
		if (width < 0)
			return width;
		height = simplefb_get_height_of(dev, of_node);
		if (height < 0)
			return height;
		stride = simplefb_get_stride_of(dev, of_node);
		if (stride < 0)
			return stride;
		format = simplefb_get_format_of(dev, of_node);
		if (IS_ERR(format))
			return PTR_ERR(format);
	} else {
		drm_err(dev, "no simplefb configuration found\n");
		return -ENODEV;
	}

	sdev->mode = simpledrm_mode(width, height);
	sdev->format = format;
	sdev->pitch = stride;

	drm_dbg_kms(dev, "display mode={" DRM_MODE_FMT "}\n",
		    DRM_MODE_ARG(&sdev->mode));
	drm_dbg_kms(dev,
		    "framebuffer format=%p4cc, size=%dx%d, stride=%d byte\n",
		    &format->format, width, height, stride);

	return 0;
}

/*
 * Memory management
 */

static int simpledrm_device_init_mm(struct simpledrm_device *sdev)
{
	struct drm_device *dev = &sdev->dev;
	struct platform_device *pdev = sdev->pdev;
	struct resource *res, *mem;
	void __iomem *screen_base;
	int ret;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -EINVAL;

	ret = devm_aperture_acquire_from_firmware(dev, res->start, resource_size(res));
	if (ret) {
		drm_err(dev, "could not acquire memory range %pr: error %d\n",
			res, ret);
		return ret;
	}

	mem = devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
				      sdev->dev.driver->name);
	if (!mem) {
		/*
		 * We cannot make this fatal. Sometimes this comes from magic
		 * spaces our resource handlers simply don't know about. Use
		 * the I/O-memory resource as-is and try to map that instead.
		 */
		drm_warn(dev, "could not acquire memory region %pr\n", res);
		mem = res;
	}

	screen_base = devm_ioremap_wc(&pdev->dev, mem->start,
				      resource_size(mem));
	if (!screen_base)
		return -ENOMEM;

	sdev->mem = mem;
	sdev->screen_base = screen_base;

	return 0;
}

/*
 * Modesetting
 */

/*
 * Support all formats of simplefb and maybe more; in order
 * of preference. The display's update function will do any
 * conversion necessary.
 *
 * TODO: Add blit helpers for remaining formats and uncomment
 *       constants.
 */
static const uint32_t simpledrm_default_formats[] = {
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_ARGB8888,
	DRM_FORMAT_RGB565,
	//DRM_FORMAT_XRGB1555,
	//DRM_FORMAT_ARGB1555,
	DRM_FORMAT_RGB888,
	DRM_FORMAT_XRGB2101010,
	DRM_FORMAT_ARGB2101010,
};

static const uint64_t simpledrm_format_modifiers[] = {
	DRM_FORMAT_MOD_LINEAR,
	DRM_FORMAT_MOD_INVALID
};

static int simpledrm_connector_helper_get_modes(struct drm_connector *connector)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(connector->dev);
	struct drm_display_mode *mode;

	mode = drm_mode_duplicate(connector->dev, &sdev->mode);
	if (!mode)
		return 0;

	if (mode->name[0] == '\0')
		drm_mode_set_name(mode);

	mode->type |= DRM_MODE_TYPE_PREFERRED;
	drm_mode_probed_add(connector, mode);

	if (mode->width_mm)
		connector->display_info.width_mm = mode->width_mm;
	if (mode->height_mm)
		connector->display_info.height_mm = mode->height_mm;

	return 1;
}

static const struct drm_connector_helper_funcs simpledrm_connector_helper_funcs = {
	.get_modes = simpledrm_connector_helper_get_modes,
};

static const struct drm_connector_funcs simpledrm_connector_funcs = {
	.reset = drm_atomic_helper_connector_reset,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.destroy = drm_connector_cleanup,
	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};

static int
simpledrm_simple_display_pipe_mode_valid(struct drm_simple_display_pipe *pipe,
				    const struct drm_display_mode *mode)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(pipe->crtc.dev);

	if (mode->hdisplay != sdev->mode.hdisplay &&
	    mode->vdisplay != sdev->mode.vdisplay)
		return MODE_ONE_SIZE;
	else if (mode->hdisplay != sdev->mode.hdisplay)
		return MODE_ONE_WIDTH;
	else if (mode->vdisplay != sdev->mode.vdisplay)
		return MODE_ONE_HEIGHT;

	return MODE_OK;
}

static void
simpledrm_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
				     struct drm_crtc_state *crtc_state,
				     struct drm_plane_state *plane_state)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(pipe->crtc.dev);
	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
	struct drm_framebuffer *fb = plane_state->fb;
	void *vmap = shadow_plane_state->data[0].vaddr; /* TODO: Use mapping abstraction */
	struct drm_device *dev = &sdev->dev;
	void __iomem *dst = sdev->screen_base;
	struct drm_rect src_clip, dst_clip;
	int idx;

	if (!fb)
		return;

	drm_rect_fp_to_int(&src_clip, &plane_state->src);

	dst_clip = plane_state->dst;
	if (!drm_rect_intersect(&dst_clip, &src_clip))
		return;

	if (!drm_dev_enter(dev, &idx))
		return;

	dst += drm_fb_clip_offset(sdev->pitch, sdev->format, &dst_clip);
	drm_fb_blit_toio(dst, sdev->pitch, sdev->format->format, vmap, fb, &src_clip);

	drm_dev_exit(idx);
}

static void
simpledrm_simple_display_pipe_disable(struct drm_simple_display_pipe *pipe)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(pipe->crtc.dev);
	struct drm_device *dev = &sdev->dev;
	int idx;

	if (!drm_dev_enter(dev, &idx))
		return;

	/* Clear screen to black if disabled */
	memset_io(sdev->screen_base, 0, sdev->pitch * sdev->mode.vdisplay);

	drm_dev_exit(idx);
}

static void
simpledrm_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
				     struct drm_plane_state *old_plane_state)
{
	struct simpledrm_device *sdev = simpledrm_device_of_dev(pipe->crtc.dev);
	struct drm_plane_state *plane_state = pipe->plane.state;
	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
	void *vmap = shadow_plane_state->data[0].vaddr; /* TODO: Use mapping abstraction */
	struct drm_framebuffer *fb = plane_state->fb;
	struct drm_device *dev = &sdev->dev;
	void __iomem *dst = sdev->screen_base;
	struct drm_rect src_clip, dst_clip;
	int idx;

	if (!fb)
		return;

	if (!drm_atomic_helper_damage_merged(old_plane_state, plane_state, &src_clip))
		return;

	dst_clip = plane_state->dst;
	if (!drm_rect_intersect(&dst_clip, &src_clip))
		return;

	if (!drm_dev_enter(dev, &idx))
		return;

	dst += drm_fb_clip_offset(sdev->pitch, sdev->format, &dst_clip);
	drm_fb_blit_toio(dst, sdev->pitch, sdev->format->format, vmap, fb, &src_clip);

	drm_dev_exit(idx);
}

static const struct drm_simple_display_pipe_funcs
simpledrm_simple_display_pipe_funcs = {
	.mode_valid = simpledrm_simple_display_pipe_mode_valid,
	.enable = simpledrm_simple_display_pipe_enable,
	.disable = simpledrm_simple_display_pipe_disable,
	.update = simpledrm_simple_display_pipe_update,
	DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
};

static const struct drm_mode_config_funcs simpledrm_mode_config_funcs = {
	.fb_create = drm_gem_fb_create_with_dirty,
	.atomic_check = drm_atomic_helper_check,
	.atomic_commit = drm_atomic_helper_commit,
};

static const uint32_t *simpledrm_device_formats(struct simpledrm_device *sdev,
						size_t *nformats_out)
{
	struct drm_device *dev = &sdev->dev;
	size_t i;

	if (sdev->nformats)
		goto out; /* don't rebuild list on recurring calls */

	/* native format goes first */
	sdev->formats[0] = sdev->format->format;
	sdev->nformats = 1;

	/* default formats go second */
	for (i = 0; i < ARRAY_SIZE(simpledrm_default_formats); ++i) {
		if (simpledrm_default_formats[i] == sdev->format->format)
			continue; /* native format already went first */
		sdev->formats[sdev->nformats] = simpledrm_default_formats[i];
		sdev->nformats++;
	}

	/*
	 * TODO: The simpledrm driver converts framebuffers to the native
	 * format when copying them to device memory. If there are more
	 * formats listed than supported by the driver, the native format
	 * is not supported by the conversion helpers. Therefore *only*
	 * support the native format and add a conversion helper ASAP.
	 */
	if (drm_WARN_ONCE(dev, i != sdev->nformats,
			  "format conversion helpers required for %p4cc",
			  &sdev->format->format)) {
		sdev->nformats = 1;
	}

out:
	*nformats_out = sdev->nformats;
	return sdev->formats;
}

static int simpledrm_device_init_modeset(struct simpledrm_device *sdev)
{
	struct drm_device *dev = &sdev->dev;
	struct drm_display_mode *mode = &sdev->mode;
	struct drm_connector *connector = &sdev->connector;
	struct drm_simple_display_pipe *pipe = &sdev->pipe;
	unsigned long max_width, max_height;
	const uint32_t *formats;
	size_t nformats;
	int ret;

	ret = drmm_mode_config_init(dev);
	if (ret)
		return ret;

	max_width = max_t(unsigned long, mode->hdisplay, DRM_SHADOW_PLANE_MAX_WIDTH);
	max_height = max_t(unsigned long, mode->vdisplay, DRM_SHADOW_PLANE_MAX_HEIGHT);

	dev->mode_config.min_width = mode->hdisplay;
	dev->mode_config.max_width = max_width;
	dev->mode_config.min_height = mode->vdisplay;
	dev->mode_config.max_height = max_height;
	dev->mode_config.preferred_depth = sdev->format->cpp[0] * 8;
	dev->mode_config.funcs = &simpledrm_mode_config_funcs;

	ret = drm_connector_init(dev, connector, &simpledrm_connector_funcs,
				 DRM_MODE_CONNECTOR_Unknown);
	if (ret)
		return ret;
	drm_connector_helper_add(connector, &simpledrm_connector_helper_funcs);
	drm_connector_set_panel_orientation_with_quirk(connector,
						       DRM_MODE_PANEL_ORIENTATION_UNKNOWN,
						       mode->hdisplay, mode->vdisplay);

	formats = simpledrm_device_formats(sdev, &nformats);

	ret = drm_simple_display_pipe_init(dev, pipe, &simpledrm_simple_display_pipe_funcs,
					   formats, nformats, simpledrm_format_modifiers,
					   connector);
	if (ret)
		return ret;

	drm_plane_enable_fb_damage_clips(&pipe->plane);

	drm_mode_config_reset(dev);

	return 0;
}

/*
 * Init / Cleanup
 */

static struct simpledrm_device *
simpledrm_device_create(struct drm_driver *drv, struct platform_device *pdev)
{
	struct simpledrm_device *sdev;
	int ret;

	sdev = devm_drm_dev_alloc(&pdev->dev, drv, struct simpledrm_device,
				  dev);
	if (IS_ERR(sdev))
		return ERR_CAST(sdev);
	sdev->pdev = pdev;
	platform_set_drvdata(pdev, sdev);

	ret = simpledrm_device_init_clocks(sdev);
	if (ret)
		return ERR_PTR(ret);
	ret = simpledrm_device_init_regulators(sdev);
	if (ret)
		return ERR_PTR(ret);
	ret = simpledrm_device_init_fb(sdev);
	if (ret)
		return ERR_PTR(ret);
	ret = simpledrm_device_init_mm(sdev);
	if (ret)
		return ERR_PTR(ret);
	ret = simpledrm_device_init_modeset(sdev);
	if (ret)
		return ERR_PTR(ret);

	return sdev;
}

/*
 * DRM driver
 */

DEFINE_DRM_GEM_FOPS(simpledrm_fops);

static struct drm_driver simpledrm_driver = {
	DRM_GEM_SHMEM_DRIVER_OPS,
	.name			= DRIVER_NAME,
	.desc			= DRIVER_DESC,
	.date			= DRIVER_DATE,
	.major			= DRIVER_MAJOR,
	.minor			= DRIVER_MINOR,
	.driver_features	= DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
	.fops			= &simpledrm_fops,
};

/*
 * Platform driver
 */

static int simpledrm_probe(struct platform_device *pdev)
{
	struct simpledrm_device *sdev;
	struct drm_device *dev;
	int ret;

	sdev = simpledrm_device_create(&simpledrm_driver, pdev);
	if (IS_ERR(sdev))
		return PTR_ERR(sdev);
	dev = &sdev->dev;

	ret = drm_dev_register(dev, 0);
	if (ret)
		return ret;

	drm_fbdev_generic_setup(dev, 0);

	return 0;
}

static int simpledrm_remove(struct platform_device *pdev)
{
	struct simpledrm_device *sdev = platform_get_drvdata(pdev);
	struct drm_device *dev = &sdev->dev;

	drm_dev_unplug(dev);

	return 0;
}

static const struct of_device_id simpledrm_of_match_table[] = {
	{ .compatible = "simple-framebuffer", },
	{ },
};
MODULE_DEVICE_TABLE(of, simpledrm_of_match_table);

static struct platform_driver simpledrm_platform_driver = {
	.driver = {
		.name = "simple-framebuffer", /* connect to sysfb */
		.of_match_table = simpledrm_of_match_table,
	},
	.probe = simpledrm_probe,
	.remove = simpledrm_remove,
};

module_platform_driver(simpledrm_platform_driver);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL v2");