Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2010 Matt Turner.
 * Copyright 2012 Red Hat
 *
 * Authors: Matthew Garrett
 *	    Matt Turner
 *	    Dave Airlie
 */

#include <linux/delay.h>
#include <linux/iosys-map.h>

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_format_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>

#include "mgag200_drv.h"

/*
 * This file contains setup code for the CRTC.
 */

static void mgag200_crtc_set_gamma_linear(struct mga_device *mdev,
					  const struct drm_format_info *format)
{
	int i;

	WREG8(DAC_INDEX + MGA1064_INDEX, 0);

	switch (format->format) {
	case DRM_FORMAT_RGB565:
		/* Use better interpolation, to take 32 values from 0 to 255 */
		for (i = 0; i < MGAG200_LUT_SIZE / 8; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 8 + i / 4);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 4 + i / 16);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 8 + i / 4);
		}
		/* Green has one more bit, so add padding with 0 for red and blue. */
		for (i = MGAG200_LUT_SIZE / 8; i < MGAG200_LUT_SIZE / 4; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 4 + i / 16);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
		}
		break;
	case DRM_FORMAT_RGB888:
	case DRM_FORMAT_XRGB8888:
		for (i = 0; i < MGAG200_LUT_SIZE; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
		}
		break;
	default:
		drm_warn_once(&mdev->base, "Unsupported format %p4cc for gamma correction\n",
			      &format->format);
		break;
	}
}

static void mgag200_crtc_set_gamma(struct mga_device *mdev,
				   const struct drm_format_info *format,
				   struct drm_color_lut *lut)
{
	int i;

	WREG8(DAC_INDEX + MGA1064_INDEX, 0);

	switch (format->format) {
	case DRM_FORMAT_RGB565:
		/* Use better interpolation, to take 32 values from lut[0] to lut[255] */
		for (i = 0; i < MGAG200_LUT_SIZE / 8; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 8 + i / 4].red >> 8);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 4 + i / 16].green >> 8);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 8 + i / 4].blue >> 8);
		}
		/* Green has one more bit, so add padding with 0 for red and blue. */
		for (i = MGAG200_LUT_SIZE / 8; i < MGAG200_LUT_SIZE / 4; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 4 + i / 16].green >> 8);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
		}
		break;
	case DRM_FORMAT_RGB888:
	case DRM_FORMAT_XRGB8888:
		for (i = 0; i < MGAG200_LUT_SIZE; i++) {
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].red >> 8);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].green >> 8);
			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].blue >> 8);
		}
		break;
	default:
		drm_warn_once(&mdev->base, "Unsupported format %p4cc for gamma correction\n",
			      &format->format);
		break;
	}
}

static inline void mga_wait_vsync(struct mga_device *mdev)
{
	unsigned long timeout = jiffies + HZ/10;
	unsigned int status = 0;

	do {
		status = RREG32(MGAREG_Status);
	} while ((status & 0x08) && time_before(jiffies, timeout));
	timeout = jiffies + HZ/10;
	status = 0;
	do {
		status = RREG32(MGAREG_Status);
	} while (!(status & 0x08) && time_before(jiffies, timeout));
}

static inline void mga_wait_busy(struct mga_device *mdev)
{
	unsigned long timeout = jiffies + HZ;
	unsigned int status = 0;
	do {
		status = RREG8(MGAREG_Status + 2);
	} while ((status & 0x01) && time_before(jiffies, timeout));
}

/*
 * This is how the framebuffer base address is stored in g200 cards:
 *   * Assume @offset is the gpu_addr variable of the framebuffer object
 *   * Then addr is the number of _pixels_ (not bytes) from the start of
 *     VRAM to the first pixel we want to display. (divided by 2 for 32bit
 *     framebuffers)
 *   * addr is stored in the CRTCEXT0, CRTCC and CRTCD registers
 *      addr<20> -> CRTCEXT0<6>
 *      addr<19-16> -> CRTCEXT0<3-0>
 *      addr<15-8> -> CRTCC<7-0>
 *      addr<7-0> -> CRTCD<7-0>
 *
 *  CRTCEXT0 has to be programmed last to trigger an update and make the
 *  new addr variable take effect.
 */
static void mgag200_set_startadd(struct mga_device *mdev,
				 unsigned long offset)
{
	struct drm_device *dev = &mdev->base;
	u32 startadd;
	u8 crtcc, crtcd, crtcext0;

	startadd = offset / 8;

	if (startadd > 0)
		drm_WARN_ON_ONCE(dev, mdev->info->bug_no_startadd);

	/*
	 * Can't store addresses any higher than that, but we also
	 * don't have more than 16 MiB of memory, so it should be fine.
	 */
	drm_WARN_ON(dev, startadd > 0x1fffff);

	RREG_ECRT(0x00, crtcext0);

	crtcc = (startadd >> 8) & 0xff;
	crtcd = startadd & 0xff;
	crtcext0 &= 0xb0;
	crtcext0 |= ((startadd >> 14) & BIT(6)) |
		    ((startadd >> 16) & 0x0f);

	WREG_CRT(0x0c, crtcc);
	WREG_CRT(0x0d, crtcd);
	WREG_ECRT(0x00, crtcext0);
}

void mgag200_init_registers(struct mga_device *mdev)
{
	u8 crtc11, misc;

	WREG_SEQ(2, 0x0f);
	WREG_SEQ(3, 0x00);
	WREG_SEQ(4, 0x0e);

	WREG_CRT(10, 0);
	WREG_CRT(11, 0);
	WREG_CRT(12, 0);
	WREG_CRT(13, 0);
	WREG_CRT(14, 0);
	WREG_CRT(15, 0);

	RREG_CRT(0x11, crtc11);
	crtc11 &= ~(MGAREG_CRTC11_CRTCPROTECT |
		    MGAREG_CRTC11_VINTEN |
		    MGAREG_CRTC11_VINTCLR);
	WREG_CRT(0x11, crtc11);

	misc = RREG8(MGA_MISC_IN);
	misc |= MGAREG_MISC_IOADSEL;
	WREG8(MGA_MISC_OUT, misc);
}

void mgag200_set_mode_regs(struct mga_device *mdev, const struct drm_display_mode *mode)
{
	const struct mgag200_device_info *info = mdev->info;
	unsigned int hdisplay, hsyncstart, hsyncend, htotal;
	unsigned int vdisplay, vsyncstart, vsyncend, vtotal;
	u8 misc, crtcext1, crtcext2, crtcext5;

	hdisplay = mode->hdisplay / 8 - 1;
	hsyncstart = mode->hsync_start / 8 - 1;
	hsyncend = mode->hsync_end / 8 - 1;
	htotal = mode->htotal / 8 - 1;

	/* Work around hardware quirk */
	if ((htotal & 0x07) == 0x06 || (htotal & 0x07) == 0x04)
		htotal++;

	vdisplay = mode->vdisplay - 1;
	vsyncstart = mode->vsync_start - 1;
	vsyncend = mode->vsync_end - 1;
	vtotal = mode->vtotal - 2;

	misc = RREG8(MGA_MISC_IN);

	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
		misc |= MGAREG_MISC_HSYNCPOL;
	else
		misc &= ~MGAREG_MISC_HSYNCPOL;

	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
		misc |= MGAREG_MISC_VSYNCPOL;
	else
		misc &= ~MGAREG_MISC_VSYNCPOL;

	crtcext1 = (((htotal - 4) & 0x100) >> 8) |
		   ((hdisplay & 0x100) >> 7) |
		   ((hsyncstart & 0x100) >> 6) |
		    (htotal & 0x40);
	if (info->has_vidrst)
		crtcext1 |= MGAREG_CRTCEXT1_VRSTEN |
			    MGAREG_CRTCEXT1_HRSTEN;

	crtcext2 = ((vtotal & 0xc00) >> 10) |
		   ((vdisplay & 0x400) >> 8) |
		   ((vdisplay & 0xc00) >> 7) |
		   ((vsyncstart & 0xc00) >> 5) |
		   ((vdisplay & 0x400) >> 3);
	crtcext5 = 0x00;

	WREG_CRT(0, htotal - 4);
	WREG_CRT(1, hdisplay);
	WREG_CRT(2, hdisplay);
	WREG_CRT(3, (htotal & 0x1F) | 0x80);
	WREG_CRT(4, hsyncstart);
	WREG_CRT(5, ((htotal & 0x20) << 2) | (hsyncend & 0x1F));
	WREG_CRT(6, vtotal & 0xFF);
	WREG_CRT(7, ((vtotal & 0x100) >> 8) |
		 ((vdisplay & 0x100) >> 7) |
		 ((vsyncstart & 0x100) >> 6) |
		 ((vdisplay & 0x100) >> 5) |
		 ((vdisplay & 0x100) >> 4) | /* linecomp */
		 ((vtotal & 0x200) >> 4) |
		 ((vdisplay & 0x200) >> 3) |
		 ((vsyncstart & 0x200) >> 2));
	WREG_CRT(9, ((vdisplay & 0x200) >> 4) |
		 ((vdisplay & 0x200) >> 3));
	WREG_CRT(16, vsyncstart & 0xFF);
	WREG_CRT(17, (vsyncend & 0x0F) | 0x20);
	WREG_CRT(18, vdisplay & 0xFF);
	WREG_CRT(20, 0);
	WREG_CRT(21, vdisplay & 0xFF);
	WREG_CRT(22, (vtotal + 1) & 0xFF);
	WREG_CRT(23, 0xc3);
	WREG_CRT(24, vdisplay & 0xFF);

	WREG_ECRT(0x01, crtcext1);
	WREG_ECRT(0x02, crtcext2);
	WREG_ECRT(0x05, crtcext5);

	WREG8(MGA_MISC_OUT, misc);
}

static u8 mgag200_get_bpp_shift(const struct drm_format_info *format)
{
	static const u8 bpp_shift[] = {0, 1, 0, 2};

	return bpp_shift[format->cpp[0] - 1];
}

/*
 * Calculates the HW offset value from the framebuffer's pitch. The
 * offset is a multiple of the pixel size and depends on the display
 * format.
 */
static u32 mgag200_calculate_offset(struct mga_device *mdev,
				    const struct drm_framebuffer *fb)
{
	u32 offset = fb->pitches[0] / fb->format->cpp[0];
	u8 bppshift = mgag200_get_bpp_shift(fb->format);

	if (fb->format->cpp[0] * 8 == 24)
		offset = (offset * 3) >> (4 - bppshift);
	else
		offset = offset >> (4 - bppshift);

	return offset;
}

static void mgag200_set_offset(struct mga_device *mdev,
			       const struct drm_framebuffer *fb)
{
	u8 crtc13, crtcext0;
	u32 offset = mgag200_calculate_offset(mdev, fb);

	RREG_ECRT(0, crtcext0);

	crtc13 = offset & 0xff;

	crtcext0 &= ~MGAREG_CRTCEXT0_OFFSET_MASK;
	crtcext0 |= (offset >> 4) & MGAREG_CRTCEXT0_OFFSET_MASK;

	WREG_CRT(0x13, crtc13);
	WREG_ECRT(0x00, crtcext0);
}

void mgag200_set_format_regs(struct mga_device *mdev, const struct drm_format_info *format)
{
	struct drm_device *dev = &mdev->base;
	unsigned int bpp, bppshift, scale;
	u8 crtcext3, xmulctrl;

	bpp = format->cpp[0] * 8;

	bppshift = mgag200_get_bpp_shift(format);
	switch (bpp) {
	case 24:
		scale = ((1 << bppshift) * 3) - 1;
		break;
	default:
		scale = (1 << bppshift) - 1;
		break;
	}

	RREG_ECRT(3, crtcext3);

	switch (bpp) {
	case 8:
		xmulctrl = MGA1064_MUL_CTL_8bits;
		break;
	case 16:
		if (format->depth == 15)
			xmulctrl = MGA1064_MUL_CTL_15bits;
		else
			xmulctrl = MGA1064_MUL_CTL_16bits;
		break;
	case 24:
		xmulctrl = MGA1064_MUL_CTL_24bits;
		break;
	case 32:
		xmulctrl = MGA1064_MUL_CTL_32_24bits;
		break;
	default:
		/* BUG: We should have caught this problem already. */
		drm_WARN_ON(dev, "invalid format depth\n");
		return;
	}

	crtcext3 &= ~GENMASK(2, 0);
	crtcext3 |= scale;

	WREG_DAC(MGA1064_MUL_CTL, xmulctrl);

	WREG_GFX(0, 0x00);
	WREG_GFX(1, 0x00);
	WREG_GFX(2, 0x00);
	WREG_GFX(3, 0x00);
	WREG_GFX(4, 0x00);
	WREG_GFX(5, 0x40);
	/* GCTL6 should be 0x05, but we configure memmapsl to 0xb8000 (text mode),
	 * so that it doesn't hang when running kexec/kdump on G200_SE rev42.
	 */
	WREG_GFX(6, 0x0d);
	WREG_GFX(7, 0x0f);
	WREG_GFX(8, 0x0f);

	WREG_ECRT(3, crtcext3);
}

void mgag200_enable_display(struct mga_device *mdev)
{
	u8 seq0, crtcext1;

	RREG_SEQ(0x00, seq0);
	seq0 |= MGAREG_SEQ0_SYNCRST |
		MGAREG_SEQ0_ASYNCRST;
	WREG_SEQ(0x00, seq0);

	/*
	 * TODO: replace busy waiting with vblank IRQ; put
	 *       msleep(50) before changing SCROFF
	 */
	mga_wait_vsync(mdev);
	mga_wait_busy(mdev);

	RREG_ECRT(0x01, crtcext1);
	crtcext1 &= ~MGAREG_CRTCEXT1_VSYNCOFF;
	crtcext1 &= ~MGAREG_CRTCEXT1_HSYNCOFF;
	WREG_ECRT(0x01, crtcext1);
}

static void mgag200_disable_display(struct mga_device *mdev)
{
	u8 seq0, crtcext1;

	RREG_SEQ(0x00, seq0);
	seq0 &= ~MGAREG_SEQ0_SYNCRST;
	WREG_SEQ(0x00, seq0);

	/*
	 * TODO: replace busy waiting with vblank IRQ; put
	 *       msleep(50) before changing SCROFF
	 */
	mga_wait_vsync(mdev);
	mga_wait_busy(mdev);

	RREG_ECRT(0x01, crtcext1);
	crtcext1 |= MGAREG_CRTCEXT1_VSYNCOFF |
		    MGAREG_CRTCEXT1_HSYNCOFF;
	WREG_ECRT(0x01, crtcext1);
}

static void mgag200_handle_damage(struct mga_device *mdev, const struct iosys_map *vmap,
				  struct drm_framebuffer *fb, struct drm_rect *clip)
{
	struct iosys_map dst = IOSYS_MAP_INIT_VADDR_IOMEM(mdev->vram);

	iosys_map_incr(&dst, drm_fb_clip_offset(fb->pitches[0], fb->format, clip));
	drm_fb_memcpy(&dst, fb->pitches, vmap, fb, clip);
}

/*
 * Primary plane
 */

const uint32_t mgag200_primary_plane_formats[] = {
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_RGB565,
	DRM_FORMAT_RGB888,
};

const size_t mgag200_primary_plane_formats_size = ARRAY_SIZE(mgag200_primary_plane_formats);

const uint64_t mgag200_primary_plane_fmtmods[] = {
	DRM_FORMAT_MOD_LINEAR,
	DRM_FORMAT_MOD_INVALID
};

int mgag200_primary_plane_helper_atomic_check(struct drm_plane *plane,
					      struct drm_atomic_state *new_state)
{
	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(new_state, plane);
	struct drm_framebuffer *new_fb = new_plane_state->fb;
	struct drm_framebuffer *fb = NULL;
	struct drm_crtc *new_crtc = new_plane_state->crtc;
	struct drm_crtc_state *new_crtc_state = NULL;
	struct mgag200_crtc_state *new_mgag200_crtc_state;
	int ret;

	if (new_crtc)
		new_crtc_state = drm_atomic_get_new_crtc_state(new_state, new_crtc);

	ret = drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state,
						  DRM_PLANE_NO_SCALING,
						  DRM_PLANE_NO_SCALING,
						  false, true);
	if (ret)
		return ret;
	else if (!new_plane_state->visible)
		return 0;

	if (plane->state)
		fb = plane->state->fb;

	if (!fb || (fb->format != new_fb->format))
		new_crtc_state->mode_changed = true; /* update PLL settings */

	new_mgag200_crtc_state = to_mgag200_crtc_state(new_crtc_state);
	new_mgag200_crtc_state->format = new_fb->format;

	return 0;
}

void mgag200_primary_plane_helper_atomic_update(struct drm_plane *plane,
						struct drm_atomic_state *old_state)
{
	struct drm_device *dev = plane->dev;
	struct mga_device *mdev = to_mga_device(dev);
	struct drm_plane_state *plane_state = plane->state;
	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(old_state, plane);
	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
	struct drm_framebuffer *fb = plane_state->fb;
	struct drm_atomic_helper_damage_iter iter;
	struct drm_rect damage;
	u8 seq1;

	if (!fb)
		return;

	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
	drm_atomic_for_each_plane_damage(&iter, &damage) {
		mgag200_handle_damage(mdev, shadow_plane_state->data, fb, &damage);
	}

	/* Always scanout image at VRAM offset 0 */
	mgag200_set_startadd(mdev, (u32)0);
	mgag200_set_offset(mdev, fb);

	if (!old_plane_state->crtc && plane_state->crtc) { // enabling
		RREG_SEQ(0x01, seq1);
		seq1 &= ~MGAREG_SEQ1_SCROFF;
		WREG_SEQ(0x01, seq1);
		msleep(20);
	}
}

void mgag200_primary_plane_helper_atomic_disable(struct drm_plane *plane,
						 struct drm_atomic_state *old_state)
{
	struct drm_device *dev = plane->dev;
	struct mga_device *mdev = to_mga_device(dev);
	u8 seq1;

	RREG_SEQ(0x01, seq1);
	seq1 |= MGAREG_SEQ1_SCROFF;
	WREG_SEQ(0x01, seq1);
	msleep(20);
}

/*
 * CRTC
 */

enum drm_mode_status mgag200_crtc_helper_mode_valid(struct drm_crtc *crtc,
						    const struct drm_display_mode *mode)
{
	struct mga_device *mdev = to_mga_device(crtc->dev);
	const struct mgag200_device_info *info = mdev->info;

	/*
	 * Some devices have additional limits on the size of the
	 * display mode.
	 */
	if (mode->hdisplay > info->max_hdisplay)
		return MODE_VIRTUAL_X;
	if (mode->vdisplay > info->max_vdisplay)
		return MODE_VIRTUAL_Y;

	if ((mode->hdisplay % 8) != 0 || (mode->hsync_start % 8) != 0 ||
	    (mode->hsync_end % 8) != 0 || (mode->htotal % 8) != 0) {
		return MODE_H_ILLEGAL;
	}

	if (mode->crtc_hdisplay > 2048 || mode->crtc_hsync_start > 4096 ||
	    mode->crtc_hsync_end > 4096 || mode->crtc_htotal > 4096 ||
	    mode->crtc_vdisplay > 2048 || mode->crtc_vsync_start > 4096 ||
	    mode->crtc_vsync_end > 4096 || mode->crtc_vtotal > 4096) {
		return MODE_BAD;
	}

	return MODE_OK;
}

int mgag200_crtc_helper_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *new_state)
{
	struct drm_device *dev = crtc->dev;
	struct mga_device *mdev = to_mga_device(dev);
	const struct mgag200_device_funcs *funcs = mdev->funcs;
	struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(new_state, crtc);
	struct drm_property_blob *new_gamma_lut = new_crtc_state->gamma_lut;
	int ret;

	if (!new_crtc_state->enable)
		return 0;

	ret = drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
	if (ret)
		return ret;

	if (new_crtc_state->mode_changed) {
		if (funcs->pixpllc_atomic_check) {
			ret = funcs->pixpllc_atomic_check(crtc, new_state);
			if (ret)
				return ret;
		}
	}

	if (new_crtc_state->color_mgmt_changed && new_gamma_lut) {
		if (new_gamma_lut->length != MGAG200_LUT_SIZE * sizeof(struct drm_color_lut)) {
			drm_dbg(dev, "Wrong size for gamma_lut %zu\n", new_gamma_lut->length);
			return -EINVAL;
		}
	}

	return 0;
}

void mgag200_crtc_helper_atomic_flush(struct drm_crtc *crtc, struct drm_atomic_state *old_state)
{
	struct drm_crtc_state *crtc_state = crtc->state;
	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
	struct drm_device *dev = crtc->dev;
	struct mga_device *mdev = to_mga_device(dev);

	if (crtc_state->enable && crtc_state->color_mgmt_changed) {
		const struct drm_format_info *format = mgag200_crtc_state->format;

		if (crtc_state->gamma_lut)
			mgag200_crtc_set_gamma(mdev, format, crtc_state->gamma_lut->data);
		else
			mgag200_crtc_set_gamma_linear(mdev, format);
	}
}

void mgag200_crtc_helper_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *old_state)
{
	struct drm_device *dev = crtc->dev;
	struct mga_device *mdev = to_mga_device(dev);
	const struct mgag200_device_funcs *funcs = mdev->funcs;
	struct drm_crtc_state *crtc_state = crtc->state;
	struct drm_display_mode *adjusted_mode = &crtc_state->adjusted_mode;
	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
	const struct drm_format_info *format = mgag200_crtc_state->format;

	if (funcs->disable_vidrst)
		funcs->disable_vidrst(mdev);

	mgag200_set_format_regs(mdev, format);
	mgag200_set_mode_regs(mdev, adjusted_mode);

	if (funcs->pixpllc_atomic_update)
		funcs->pixpllc_atomic_update(crtc, old_state);

	mgag200_enable_display(mdev);

	if (funcs->enable_vidrst)
		funcs->enable_vidrst(mdev);
}

void mgag200_crtc_helper_atomic_disable(struct drm_crtc *crtc, struct drm_atomic_state *old_state)
{
	struct mga_device *mdev = to_mga_device(crtc->dev);
	const struct mgag200_device_funcs *funcs = mdev->funcs;

	if (funcs->disable_vidrst)
		funcs->disable_vidrst(mdev);

	mgag200_disable_display(mdev);

	if (funcs->enable_vidrst)
		funcs->enable_vidrst(mdev);
}

void mgag200_crtc_reset(struct drm_crtc *crtc)
{
	struct mgag200_crtc_state *mgag200_crtc_state;

	if (crtc->state)
		crtc->funcs->atomic_destroy_state(crtc, crtc->state);

	mgag200_crtc_state = kzalloc(sizeof(*mgag200_crtc_state), GFP_KERNEL);
	if (mgag200_crtc_state)
		__drm_atomic_helper_crtc_reset(crtc, &mgag200_crtc_state->base);
	else
		__drm_atomic_helper_crtc_reset(crtc, NULL);
}

struct drm_crtc_state *mgag200_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
{
	struct drm_crtc_state *crtc_state = crtc->state;
	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
	struct mgag200_crtc_state *new_mgag200_crtc_state;

	if (!crtc_state)
		return NULL;

	new_mgag200_crtc_state = kzalloc(sizeof(*new_mgag200_crtc_state), GFP_KERNEL);
	if (!new_mgag200_crtc_state)
		return NULL;
	__drm_atomic_helper_crtc_duplicate_state(crtc, &new_mgag200_crtc_state->base);

	new_mgag200_crtc_state->format = mgag200_crtc_state->format;
	memcpy(&new_mgag200_crtc_state->pixpllc, &mgag200_crtc_state->pixpllc,
	       sizeof(new_mgag200_crtc_state->pixpllc));

	return &new_mgag200_crtc_state->base;
}

void mgag200_crtc_atomic_destroy_state(struct drm_crtc *crtc, struct drm_crtc_state *crtc_state)
{
	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);

	__drm_atomic_helper_crtc_destroy_state(&mgag200_crtc_state->base);
	kfree(mgag200_crtc_state);
}

/*
 * Connector
 */

int mgag200_vga_connector_helper_get_modes(struct drm_connector *connector)
{
	struct mga_device *mdev = to_mga_device(connector->dev);
	int ret;

	/*
	 * Protect access to I/O registers from concurrent modesetting
	 * by acquiring the I/O-register lock.
	 */
	mutex_lock(&mdev->rmmio_lock);
	ret = drm_connector_helper_get_modes_from_ddc(connector);
	mutex_unlock(&mdev->rmmio_lock);

	return ret;
}

/*
 * Mode config
 */

static void mgag200_mode_config_helper_atomic_commit_tail(struct drm_atomic_state *state)
{
	struct mga_device *mdev = to_mga_device(state->dev);

	/*
	 * Concurrent operations could possibly trigger a call to
	 * drm_connector_helper_funcs.get_modes by trying to read the
	 * display modes. Protect access to I/O registers by acquiring
	 * the I/O-register lock.
	 */
	mutex_lock(&mdev->rmmio_lock);
	drm_atomic_helper_commit_tail(state);
	mutex_unlock(&mdev->rmmio_lock);
}

static const struct drm_mode_config_helper_funcs mgag200_mode_config_helper_funcs = {
	.atomic_commit_tail = mgag200_mode_config_helper_atomic_commit_tail,
};

/* Calculates a mode's required memory bandwidth (in KiB/sec). */
static uint32_t mgag200_calculate_mode_bandwidth(const struct drm_display_mode *mode,
						 unsigned int bits_per_pixel)
{
	uint32_t total_area, divisor;
	uint64_t active_area, pixels_per_second, bandwidth;
	uint64_t bytes_per_pixel = (bits_per_pixel + 7) / 8;

	divisor = 1024;

	if (!mode->htotal || !mode->vtotal || !mode->clock)
		return 0;

	active_area = mode->hdisplay * mode->vdisplay;
	total_area = mode->htotal * mode->vtotal;

	pixels_per_second = active_area * mode->clock * 1000;
	do_div(pixels_per_second, total_area);

	bandwidth = pixels_per_second * bytes_per_pixel * 100;
	do_div(bandwidth, divisor);

	return (uint32_t)bandwidth;
}

static enum drm_mode_status mgag200_mode_config_mode_valid(struct drm_device *dev,
							   const struct drm_display_mode *mode)
{
	static const unsigned int max_bpp = 4; // DRM_FORMAT_XRGB8888
	struct mga_device *mdev = to_mga_device(dev);
	unsigned long fbsize, fbpages, max_fbpages;
	const struct mgag200_device_info *info = mdev->info;

	max_fbpages = mdev->vram_available >> PAGE_SHIFT;

	fbsize = mode->hdisplay * mode->vdisplay * max_bpp;
	fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE);

	if (fbpages > max_fbpages)
		return MODE_MEM;

	/*
	 * Test the mode's required memory bandwidth if the device
	 * specifies a maximum. Not all devices do though.
	 */
	if (info->max_mem_bandwidth) {
		uint32_t mode_bandwidth = mgag200_calculate_mode_bandwidth(mode, max_bpp * 8);

		if (mode_bandwidth > (info->max_mem_bandwidth * 1024))
			return MODE_BAD;
	}

	return MODE_OK;
}

static const struct drm_mode_config_funcs mgag200_mode_config_funcs = {
	.fb_create = drm_gem_fb_create_with_dirty,
	.mode_valid = mgag200_mode_config_mode_valid,
	.atomic_check = drm_atomic_helper_check,
	.atomic_commit = drm_atomic_helper_commit,
};

int mgag200_mode_config_init(struct mga_device *mdev, resource_size_t vram_available)
{
	struct drm_device *dev = &mdev->base;
	int ret;

	mdev->vram_available = vram_available;

	ret = drmm_mode_config_init(dev);
	if (ret) {
		drm_err(dev, "drmm_mode_config_init() failed: %d\n", ret);
		return ret;
	}

	dev->mode_config.max_width = MGAG200_MAX_FB_WIDTH;
	dev->mode_config.max_height = MGAG200_MAX_FB_HEIGHT;
	dev->mode_config.preferred_depth = 24;
	dev->mode_config.funcs = &mgag200_mode_config_funcs;
	dev->mode_config.helper_private = &mgag200_mode_config_helper_funcs;

	return 0;
}