aboutsummaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/i915/intel_crt.c
blob: db59bb9fbe23f75b6be9e182937b4ff6588cfafe (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
/*
 * Copyright © 2006-2007 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 *	Eric Anholt <eric@anholt.net>
 */

#include <linux/dmi.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_edid.h>
#include "intel_drv.h"
#include <drm/i915_drm.h>
#include "i915_drv.h"

/* Here's the desired hotplug mode */
#define ADPA_HOTPLUG_BITS (ADPA_CRT_HOTPLUG_PERIOD_128 |		\
			   ADPA_CRT_HOTPLUG_WARMUP_10MS |		\
			   ADPA_CRT_HOTPLUG_SAMPLE_4S |			\
			   ADPA_CRT_HOTPLUG_VOLTAGE_50 |		\
			   ADPA_CRT_HOTPLUG_VOLREF_325MV |		\
			   ADPA_CRT_HOTPLUG_ENABLE)

struct intel_crt {
	struct intel_encoder base;
	/* DPMS state is stored in the connector, which we need in the
	 * encoder's enable/disable callbacks */
	struct intel_connector *connector;
	bool force_hotplug_required;
	u32 adpa_reg;
};

static struct intel_crt *intel_encoder_to_crt(struct intel_encoder *encoder)
{
	return container_of(encoder, struct intel_crt, base);
}

static struct intel_crt *intel_attached_crt(struct drm_connector *connector)
{
	return intel_encoder_to_crt(intel_attached_encoder(connector));
}

static bool intel_crt_get_hw_state(struct intel_encoder *encoder,
				   enum pipe *pipe)
{
	struct drm_device *dev = encoder->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_crt *crt = intel_encoder_to_crt(encoder);
	u32 tmp;

	tmp = I915_READ(crt->adpa_reg);

	if (!(tmp & ADPA_DAC_ENABLE))
		return false;

	if (HAS_PCH_CPT(dev))
		*pipe = PORT_TO_PIPE_CPT(tmp);
	else
		*pipe = PORT_TO_PIPE(tmp);

	return true;
}

static unsigned int intel_crt_get_flags(struct intel_encoder *encoder)
{
	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
	struct intel_crt *crt = intel_encoder_to_crt(encoder);
	u32 tmp, flags = 0;

	tmp = I915_READ(crt->adpa_reg);

	if (tmp & ADPA_HSYNC_ACTIVE_HIGH)
		flags |= DRM_MODE_FLAG_PHSYNC;
	else
		flags |= DRM_MODE_FLAG_NHSYNC;

	if (tmp & ADPA_VSYNC_ACTIVE_HIGH)
		flags |= DRM_MODE_FLAG_PVSYNC;
	else
		flags |= DRM_MODE_FLAG_NVSYNC;

	return flags;
}

static void intel_crt_get_config(struct intel_encoder *encoder,
				 struct intel_crtc_config *pipe_config)
{
	struct drm_device *dev = encoder->base.dev;

	pipe_config->adjusted_mode.flags |= intel_crt_get_flags(encoder);
}

static void hsw_crt_get_config(struct intel_encoder *encoder,
			       struct intel_crtc_config *pipe_config)
{
	intel_ddi_get_config(encoder, pipe_config);

	pipe_config->adjusted_mode.flags &= ~(DRM_MODE_FLAG_PHSYNC |
					      DRM_MODE_FLAG_NHSYNC |
					      DRM_MODE_FLAG_PVSYNC |
					      DRM_MODE_FLAG_NVSYNC);
	pipe_config->adjusted_mode.flags |= intel_crt_get_flags(encoder);
}

/* Note: The caller is required to filter out dpms modes not supported by the
 * platform. */
static void intel_crt_set_dpms(struct intel_encoder *encoder, int mode)
{
	struct drm_device *dev = encoder->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_crt *crt = intel_encoder_to_crt(encoder);
	u32 temp;

	temp = I915_READ(crt->adpa_reg);
	temp &= ~(ADPA_HSYNC_CNTL_DISABLE | ADPA_VSYNC_CNTL_DISABLE);
	temp &= ~ADPA_DAC_ENABLE;

	switch (mode) {
	case DRM_MODE_DPMS_ON:
		temp |= ADPA_DAC_ENABLE;
		break;
	case DRM_MODE_DPMS_STANDBY:
		temp |= ADPA_DAC_ENABLE | ADPA_HSYNC_CNTL_DISABLE;
		break;
	case DRM_MODE_DPMS_SUSPEND:
		temp |= ADPA_DAC_ENABLE | ADPA_VSYNC_CNTL_DISABLE;
		break;
	case DRM_MODE_DPMS_OFF:
		temp |= ADPA_HSYNC_CNTL_DISABLE | ADPA_VSYNC_CNTL_DISABLE;
		break;
	}

	I915_WRITE(crt->adpa_reg, temp);
}

static void intel_disable_crt(struct intel_encoder *encoder)
{
	intel_crt_set_dpms(encoder, DRM_MODE_DPMS_OFF);
}

static void intel_enable_crt(struct intel_encoder *encoder)
{
	struct intel_crt *crt = intel_encoder_to_crt(encoder);

	intel_crt_set_dpms(encoder, crt->connector->base.dpms);
}

/* Special dpms function to support cloning between dvo/sdvo/crt. */
static void intel_crt_dpms(struct drm_connector *connector, int mode)
{
	struct drm_device *dev = connector->dev;
	struct intel_encoder *encoder = intel_attached_encoder(connector);
	struct drm_crtc *crtc;
	int old_dpms;

	/* PCH platforms and VLV only support on/off. */
	if (INTEL_INFO(dev)->gen >= 5 && mode != DRM_MODE_DPMS_ON)
		mode = DRM_MODE_DPMS_OFF;

	if (mode == connector->dpms)
		return;

	old_dpms = connector->dpms;
	connector->dpms = mode;

	/* Only need to change hw state when actually enabled */
	crtc = encoder->base.crtc;
	if (!crtc) {
		encoder->connectors_active = false;
		return;
	}

	/* We need the pipe to run for anything but OFF. */
	if (mode == DRM_MODE_DPMS_OFF)
		encoder->connectors_active = false;
	else
		encoder->connectors_active = true;

	/* We call connector dpms manually below in case pipe dpms doesn't
	 * change due to cloning. */
	if (mode < old_dpms) {
		/* From off to on, enable the pipe first. */
		intel_crtc_update_dpms(crtc);

		intel_crt_set_dpms(encoder, mode);
	} else {
		intel_crt_set_dpms(encoder, mode);

		intel_crtc_update_dpms(crtc);
	}

	intel_modeset_check_state(connector->dev);
}

static int intel_crt_mode_valid(struct drm_connector *connector,
				struct drm_display_mode *mode)
{
	struct drm_device *dev = connector->dev;

	int max_clock = 0;
	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
		return MODE_NO_DBLESCAN;

	if (mode->clock < 25000)
		return MODE_CLOCK_LOW;

	if (IS_GEN2(dev))
		max_clock = 350000;
	else
		max_clock = 400000;
	if (mode->clock > max_clock)
		return MODE_CLOCK_HIGH;

	/* The FDI receiver on LPT only supports 8bpc and only has 2 lanes. */
	if (HAS_PCH_LPT(dev) &&
	    (ironlake_get_lanes_required(mode->clock, 270000, 24) > 2))
		return MODE_CLOCK_HIGH;

	return MODE_OK;
}

static bool intel_crt_compute_config(struct intel_encoder *encoder,
				     struct intel_crtc_config *pipe_config)
{
	struct drm_device *dev = encoder->base.dev;

	if (HAS_PCH_SPLIT(dev))
		pipe_config->has_pch_encoder = true;

	/* LPT FDI RX only supports 8bpc. */
	if (HAS_PCH_LPT(dev))
		pipe_config->pipe_bpp = 24;

	return true;
}

static void intel_crt_mode_set(struct intel_encoder *encoder)
{

	struct drm_device *dev = encoder->base.dev;
	struct intel_crt *crt = intel_encoder_to_crt(encoder);
	struct intel_crtc *crtc = to_intel_crtc(encoder->base.crtc);
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_display_mode *adjusted_mode = &crtc->config.adjusted_mode;
	u32 adpa;

	if (HAS_PCH_SPLIT(dev))
		adpa = ADPA_HOTPLUG_BITS;
	else
		adpa = 0;

	if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
		adpa |= ADPA_HSYNC_ACTIVE_HIGH;
	if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
		adpa |= ADPA_VSYNC_ACTIVE_HIGH;

	/* For CPT allow 3 pipe config, for others just use A or B */
	if (HAS_PCH_LPT(dev))
		; /* Those bits don't exist here */
	else if (HAS_PCH_CPT(dev))
		adpa |= PORT_TRANS_SEL_CPT(crtc->pipe);
	else if (crtc->pipe == 0)
		adpa |= ADPA_PIPE_A_SELECT;
	else
		adpa |= ADPA_PIPE_B_SELECT;

	if (!HAS_PCH_SPLIT(dev))
		I915_WRITE(BCLRPAT(crtc->pipe), 0);

	I915_WRITE(crt->adpa_reg, adpa);
}

static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector)
{
	struct drm_device *dev = connector->dev;
	struct intel_crt *crt = intel_attached_crt(connector);
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 adpa;
	bool ret;

	/* The first time through, trigger an explicit detection cycle */
	if (crt->force_hotplug_required) {
		bool turn_off_dac = HAS_PCH_SPLIT(dev);
		u32 save_adpa;

		crt->force_hotplug_required = 0;

		save_adpa = adpa = I915_READ(crt->adpa_reg);
		DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);

		adpa |= ADPA_CRT_HOTPLUG_FORCE_TRIGGER;
		if (turn_off_dac)
			adpa &= ~ADPA_DAC_ENABLE;

		I915_WRITE(crt->adpa_reg, adpa);

		if (wait_for((I915_READ(crt->adpa_reg) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
			     1000))
			DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");

		if (turn_off_dac) {
			I915_WRITE(crt->adpa_reg, save_adpa);
			POSTING_READ(crt->adpa_reg);
		}
	}

	/* Check the status to see if both blue and green are on now */
	adpa = I915_READ(crt->adpa_reg);
	if ((adpa & ADPA_CRT_HOTPLUG_MONITOR_MASK) != 0)
		ret = true;
	else
		ret = false;
	DRM_DEBUG_KMS("ironlake hotplug adpa=0x%x, result %d\n", adpa, ret);

	return ret;
}

static bool valleyview_crt_detect_hotplug(struct drm_connector *connector)
{
	struct drm_device *dev = connector->dev;
	struct intel_crt *crt = intel_attached_crt(connector);
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 adpa;
	bool ret;
	u32 save_adpa;

	save_adpa = adpa = I915_READ(crt->adpa_reg);
	DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);

	adpa |= ADPA_CRT_HOTPLUG_FORCE_TRIGGER;

	I915_WRITE(crt->adpa_reg, adpa);

	if (wait_for((I915_READ(crt->adpa_reg) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
		     1000)) {
		DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");
		I915_WRITE(crt->adpa_reg, save_adpa);
	}

	/* Check the status to see if both blue and green are on now */
	adpa = I915_READ(crt->adpa_reg);
	if ((adpa & ADPA_CRT_HOTPLUG_MONITOR_MASK) != 0)
		ret = true;
	else
		ret = false;

	DRM_DEBUG_KMS("valleyview hotplug adpa=0x%x, result %d\n", adpa, ret);

	/* FIXME: debug force function and remove */
	ret = true;

	return ret;
}

/**
 * Uses CRT_HOTPLUG_EN and CRT_HOTPLUG_STAT to detect CRT presence.
 *
 * Not for i915G/i915GM
 *
 * \return true if CRT is connected.
 * \return false if CRT is disconnected.
 */
static bool intel_crt_detect_hotplug(struct drm_connector *connector)
{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 hotplug_en, orig, stat;
	bool ret = false;
	int i, tries = 0;

	if (HAS_PCH_SPLIT(dev))
		return intel_ironlake_crt_detect_hotplug(connector);

	if (IS_VALLEYVIEW(dev))
		return valleyview_crt_detect_hotplug(connector);

	/*
	 * On 4 series desktop, CRT detect sequence need to be done twice
	 * to get a reliable result.
	 */

	if (IS_G4X(dev) && !IS_GM45(dev))
		tries = 2;
	else
		tries = 1;
	hotplug_en = orig = I915_READ(PORT_HOTPLUG_EN);
	hotplug_en |= CRT_HOTPLUG_FORCE_DETECT;

	for (i = 0; i < tries ; i++) {
		/* turn on the FORCE_DETECT */
		I915_WRITE(PORT_HOTPLUG_EN, hotplug_en);
		/* wait for FORCE_DETECT to go off */
		if (wait_for((I915_READ(PORT_HOTPLUG_EN) &
			      CRT_HOTPLUG_FORCE_DETECT) == 0,
			     1000))
			DRM_DEBUG_KMS("timed out waiting for FORCE_DETECT to go off");
	}

	stat = I915_READ(PORT_HOTPLUG_STAT);
	if ((stat & CRT_HOTPLUG_MONITOR_MASK) != CRT_HOTPLUG_MONITOR_NONE)
		ret = true;

	/* clear the interrupt we just generated, if any */
	I915_WRITE(PORT_HOTPLUG_STAT, CRT_HOTPLUG_INT_STATUS);

	/* and put the bits back */
	I915_WRITE(PORT_HOTPLUG_EN, orig);

	return ret;
}

static struct edid *intel_crt_get_edid(struct drm_connector *connector,
				struct i2c_adapter *i2c)
{
	struct edid *edid;

	edid = drm_get_edid(connector, i2c);

	if (!edid && !intel_gmbus_is_forced_bit(i2c)) {
		DRM_DEBUG_KMS("CRT GMBUS EDID read failed, retry using GPIO bit-banging\n");
		intel_gmbus_force_bit(i2c, true);
		edid = drm_get_edid(connector, i2c);
		intel_gmbus_force_bit(i2c, false);
	}

	return edid;
}

/* local version of intel_ddc_get_modes() to use intel_crt_get_edid() */
static int intel_crt_ddc_get_modes(struct drm_connector *connector,
				struct i2c_adapter *adapter)
{
	struct edid *edid;
	int ret;

	edid = intel_crt_get_edid(connector, adapter);
	if (!edid)
		return 0;

	ret = intel_connector_update_modes(connector, edid);
	kfree(edid);

	return ret;
}

static bool intel_crt_detect_ddc(struct drm_connector *connector)
{
	struct intel_crt *crt = intel_attached_crt(connector);
	struct drm_i915_private *dev_priv = crt->base.base.dev->dev_private;
	struct edid *edid;
	struct i2c_adapter *i2c;

	BUG_ON(crt->base.type != INTEL_OUTPUT_ANALOG);

	i2c = intel_gmbus_get_adapter(dev_priv, dev_priv->vbt.crt_ddc_pin);
	edid = intel_crt_get_edid(connector, i2c);

	if (edid) {
		bool is_digital = edid->input & DRM_EDID_INPUT_DIGITAL;

		/*
		 * This may be a DVI-I connector with a shared DDC
		 * link between analog and digital outputs, so we
		 * have to check the EDID input spec of the attached device.
		 */
		if (!is_digital) {
			DRM_DEBUG_KMS("CRT detected via DDC:0x50 [EDID]\n");
			return true;
		}

		DRM_DEBUG_KMS("CRT not detected via DDC:0x50 [EDID reports a digital panel]\n");
	} else {
		DRM_DEBUG_KMS("CRT not detected via DDC:0x50 [no valid EDID found]\n");
	}

	kfree(edid);

	return false;
}

static enum drm_connector_status
intel_crt_load_detect(struct intel_crt *crt)
{
	struct drm_device *dev = crt->base.base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t pipe = to_intel_crtc(crt->base.base.crtc)->pipe;
	uint32_t save_bclrpat;
	uint32_t save_vtotal;
	uint32_t vtotal, vactive;
	uint32_t vsample;
	uint32_t vblank, vblank_start, vblank_end;
	uint32_t dsl;
	uint32_t bclrpat_reg;
	uint32_t vtotal_reg;
	uint32_t vblank_reg;
	uint32_t vsync_reg;
	uint32_t pipeconf_reg;
	uint32_t pipe_dsl_reg;
	uint8_t	st00;
	enum drm_connector_status status;

	DRM_DEBUG_KMS("starting load-detect on CRT\n");

	bclrpat_reg = BCLRPAT(pipe);
	vtotal_reg = VTOTAL(pipe);
	vblank_reg = VBLANK(pipe);
	vsync_reg = VSYNC(pipe);
	pipeconf_reg = PIPECONF(pipe);
	pipe_dsl_reg = PIPEDSL(pipe);

	save_bclrpat = I915_READ(bclrpat_reg);
	save_vtotal = I915_READ(vtotal_reg);
	vblank = I915_READ(vblank_reg);

	vtotal = ((save_vtotal >> 16) & 0xfff) + 1;
	vactive = (save_vtotal & 0x7ff) + 1;

	vblank_start = (vblank & 0xfff) + 1;
	vblank_end = ((vblank >> 16) & 0xfff) + 1;

	/* Set the border color to purple. */
	I915_WRITE(bclrpat_reg, 0x500050);

	if (!IS_GEN2(dev)) {
		uint32_t pipeconf = I915_READ(pipeconf_reg);
		I915_WRITE(pipeconf_reg, pipeconf | PIPECONF_FORCE_BORDER);
		POSTING_READ(pipeconf_reg);
		/* Wait for next Vblank to substitue
		 * border color for Color info */
		intel_wait_for_vblank(dev, pipe);
		st00 = I915_READ8(VGA_MSR_WRITE);
		status = ((st00 & (1 << 4)) != 0) ?
			connector_status_connected :
			connector_status_disconnected;

		I915_WRITE(pipeconf_reg, pipeconf);
	} else {
		bool restore_vblank = false;
		int count, detect;

		/*
		* If there isn't any border, add some.
		* Yes, this will flicker
		*/
		if (vblank_start <= vactive && vblank_end >= vtotal) {
			uint32_t vsync = I915_READ(vsync_reg);
			uint32_t vsync_start = (vsync & 0xffff) + 1;

			vblank_start = vsync_start;
			I915_WRITE(vblank_reg,
				   (vblank_start - 1) |
				   ((vblank_end - 1) << 16));
			restore_vblank = true;
		}
		/* sample in the vertical border, selecting the larger one */
		if (vblank_start - vactive >= vtotal - vblank_end)
			vsample = (vblank_start + vactive) >> 1;
		else
			vsample = (vtotal + vblank_end) >> 1;

		/*
		 * Wait for the border to be displayed
		 */
		while (I915_READ(pipe_dsl_reg) >= vactive)
			;
		while ((dsl = I915_READ(pipe_dsl_reg)) <= vsample)
			;
		/*
		 * Watch ST00 for an entire scanline
		 */
		detect = 0;
		count = 0;
		do {
			count++;
			/* Read the ST00 VGA status register */
			st00 = I915_READ8(VGA_MSR_WRITE);
			if (st00 & (1 << 4))
				detect++;
		} while ((I915_READ(pipe_dsl_reg) == dsl));

		/* restore vblank if necessary */
		if (restore_vblank)
			I915_WRITE(vblank_reg, vblank);
		/*
		 * If more than 3/4 of the scanline detected a monitor,
		 * then it is assumed to be present. This works even on i830,
		 * where there isn't any way to force the border color across
		 * the screen
		 */
		status = detect * 4 > count * 3 ?
			 connector_status_connected :
			 connector_status_disconnected;
	}

	/* Restore previous settings */
	I915_WRITE(bclrpat_reg, save_bclrpat);

	return status;
}

static enum drm_connector_status
intel_crt_detect(struct drm_connector *connector, bool force)
{
	struct drm_device *dev = connector->dev;
	struct intel_crt *crt = intel_attached_crt(connector);
	enum drm_connector_status status;
	struct intel_load_detect_pipe tmp;

	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force=%d\n",
		      connector->base.id, drm_get_connector_name(connector),
		      force);

	if (I915_HAS_HOTPLUG(dev)) {
		/* We can not rely on the HPD pin always being correctly wired
		 * up, for example many KVM do not pass it through, and so
		 * only trust an assertion that the monitor is connected.
		 */
		if (intel_crt_detect_hotplug(connector)) {
			DRM_DEBUG_KMS("CRT detected via hotplug\n");
			return connector_status_connected;
		} else
			DRM_DEBUG_KMS("CRT not detected via hotplug\n");
	}

	if (intel_crt_detect_ddc(connector))
		return connector_status_connected;

	/* Load detection is broken on HPD capable machines. Whoever wants a
	 * broken monitor (without edid) to work behind a broken kvm (that fails
	 * to have the right resistors for HP detection) needs to fix this up.
	 * For now just bail out. */
	if (I915_HAS_HOTPLUG(dev))
		return connector_status_disconnected;

	if (!force)
		return connector->status;

	/* for pre-945g platforms use load detect */
	if (intel_get_load_detect_pipe(connector, NULL, &tmp)) {
		if (intel_crt_detect_ddc(connector))
			status = connector_status_connected;
		else
			status = intel_crt_load_detect(crt);
		intel_release_load_detect_pipe(connector, &tmp);
	} else
		status = connector_status_unknown;

	return status;
}

static void intel_crt_destroy(struct drm_connector *connector)
{
	drm_sysfs_connector_remove(connector);
	drm_connector_cleanup(connector);
	kfree(connector);
}

static int intel_crt_get_modes(struct drm_connector *connector)
{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;
	struct i2c_adapter *i2c;

	i2c = intel_gmbus_get_adapter(dev_priv, dev_priv->vbt.crt_ddc_pin);
	ret = intel_crt_ddc_get_modes(connector, i2c);
	if (ret || !IS_G4X(dev))
		return ret;

	/* Try to probe digital port for output in DVI-I -> VGA mode. */
	i2c = intel_gmbus_get_adapter(dev_priv, GMBUS_PORT_DPB);
	return intel_crt_ddc_get_modes(connector, i2c);
}

static int intel_crt_set_property(struct drm_connector *connector,
				  struct drm_property *property,
				  uint64_t value)
{
	return 0;
}

static void intel_crt_reset(struct drm_connector *connector)
{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_crt *crt = intel_attached_crt(connector);

	if (INTEL_INFO(dev)->gen >= 5) {
		u32 adpa;

		adpa = I915_READ(crt->adpa_reg);
		adpa &= ~ADPA_CRT_HOTPLUG_MASK;
		adpa |= ADPA_HOTPLUG_BITS;
		I915_WRITE(crt->adpa_reg, adpa);
		POSTING_READ(crt->adpa_reg);

		DRM_DEBUG_KMS("pch crt adpa set to 0x%x\n", adpa);
		crt->force_hotplug_required = 1;
	}

}

/*
 * Routines for controlling stuff on the analog port
 */

static const struct drm_connector_funcs intel_crt_connector_funcs = {
	.reset = intel_crt_reset,
	.dpms = intel_crt_dpms,
	.detect = intel_crt_detect,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.destroy = intel_crt_destroy,
	.set_property = intel_crt_set_property,
};

static const struct drm_connector_helper_funcs intel_crt_connector_helper_funcs = {
	.mode_valid = intel_crt_mode_valid,
	.get_modes = intel_crt_get_modes,
	.best_encoder = intel_best_encoder,
};

static const struct drm_encoder_funcs intel_crt_enc_funcs = {
	.destroy = intel_encoder_destroy,
};

static int __init intel_no_crt_dmi_callback(const struct dmi_system_id *id)
{
	DRM_INFO("Skipping CRT initialization for %s\n", id->ident);
	return 1;
}

static const struct dmi_system_id intel_no_crt[] = {
	{
		.callback = intel_no_crt_dmi_callback,
		.ident = "ACER ZGB",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "ACER"),
			DMI_MATCH(DMI_PRODUCT_NAME, "ZGB"),
		},
	},
	{ }
};

void intel_crt_init(struct drm_device *dev)
{
	struct drm_connector *connector;
	struct intel_crt *crt;
	struct intel_connector *intel_connector;
	struct drm_i915_private *dev_priv = dev->dev_private;

	/* Skip machines without VGA that falsely report hotplug events */
	if (dmi_check_system(intel_no_crt))
		return;

	crt = kzalloc(sizeof(struct intel_crt), GFP_KERNEL);
	if (!crt)
		return;

	intel_connector = kzalloc(sizeof(struct intel_connector), GFP_KERNEL);
	if (!intel_connector) {
		kfree(crt);
		return;
	}

	connector = &intel_connector->base;
	crt->connector = intel_connector;
	drm_connector_init(dev, &intel_connector->base,
			   &intel_crt_connector_funcs, DRM_MODE_CONNECTOR_VGA);

	drm_encoder_init(dev, &crt->base.base, &intel_crt_enc_funcs,
			 DRM_MODE_ENCODER_DAC);

	intel_connector_attach_encoder(intel_connector, &crt->base);

	crt->base.type = INTEL_OUTPUT_ANALOG;
	crt->base.cloneable = true;
	if (IS_I830(dev))
		crt->base.crtc_mask = (1 << 0);
	else
		crt->base.crtc_mask = (1 << 0) | (1 << 1) | (1 << 2);

	if (IS_GEN2(dev))
		connector->interlace_allowed = 0;
	else
		connector->interlace_allowed = 1;
	connector->doublescan_allowed = 0;

	if (HAS_PCH_SPLIT(dev))
		crt->adpa_reg = PCH_ADPA;
	else if (IS_VALLEYVIEW(dev))
		crt->adpa_reg = VLV_ADPA;
	else
		crt->adpa_reg = ADPA;

	crt->base.compute_config = intel_crt_compute_config;
	crt->base.mode_set = intel_crt_mode_set;
	crt->base.disable = intel_disable_crt;
	crt->base.enable = intel_enable_crt;
	if (IS_HASWELL(dev))
		crt->base.get_config = hsw_crt_get_config;
	else
		crt->base.get_config = intel_crt_get_config;
	if (I915_HAS_HOTPLUG(dev))
		crt->base.hpd_pin = HPD_CRT;
	if (HAS_DDI(dev))
		crt->base.get_hw_state = intel_ddi_get_hw_state;
	else
		crt->base.get_hw_state = intel_crt_get_hw_state;
	intel_connector->get_hw_state = intel_connector_get_hw_state;

	drm_connector_helper_add(connector, &intel_crt_connector_helper_funcs);

	drm_sysfs_connector_add(connector);

	if (!I915_HAS_HOTPLUG(dev))
		intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT;

	/*
	 * Configure the automatic hotplug detection stuff
	 */
	crt->force_hotplug_required = 0;

	/*
	 * TODO: find a proper way to discover whether we need to set the the
	 * polarity and link reversal bits or not, instead of relying on the
	 * BIOS.
	 */
	if (HAS_PCH_LPT(dev)) {
		u32 fdi_config = FDI_RX_POLARITY_REVERSED_LPT |
				 FDI_RX_LINK_REVERSAL_OVERRIDE;

		dev_priv->fdi_rx_config = I915_READ(_FDI_RXA_CTL) & fdi_config;
	}
}