summaryrefslogtreecommitdiffstats
path: root/drivers/video/fbdev/gbefb.c
blob: b63d55f481fae421cbea5cb71466401835e23a3d (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
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
/*
 *  SGI GBE frame buffer driver
 *
 *  Copyright (C) 1999 Silicon Graphics, Inc. - Jeffrey Newquist
 *  Copyright (C) 2002 Vivien Chappelier <vivien.chappelier@linux-mips.org>
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License. See the file COPYING in the main directory of this archive for
 *  more details.
 */

#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/io.h>

#ifdef CONFIG_MIPS
#include <asm/addrspace.h>
#endif
#include <asm/byteorder.h>
#include <asm/tlbflush.h>

#include <video/gbe.h>

static struct sgi_gbe *gbe;

struct gbefb_par {
	struct fb_var_screeninfo var;
	struct gbe_timing_info timing;
	int wc_cookie;
	int valid;
};

#ifdef CONFIG_SGI_IP32
#define GBE_BASE	0x16000000 /* SGI O2 */
#endif

/* macro for fastest write-though access to the framebuffer */
#ifdef CONFIG_MIPS
#ifdef CONFIG_CPU_R10000
#define pgprot_fb(_prot) (((_prot) & (~_CACHE_MASK)) | _CACHE_UNCACHED_ACCELERATED)
#else
#define pgprot_fb(_prot) (((_prot) & (~_CACHE_MASK)) | _CACHE_CACHABLE_NO_WA)
#endif
#endif
#ifdef CONFIG_X86
#define pgprot_fb(_prot) (((_prot) & ~_PAGE_CACHE_MASK) |	\
			  cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS))
#endif

/*
 *  RAM we reserve for the frame buffer. This defines the maximum screen
 *  size
 */
#if CONFIG_FB_GBE_MEM > 8
#error GBE Framebuffer cannot use more than 8MB of memory
#endif

#define TILE_SHIFT 16
#define TILE_SIZE (1 << TILE_SHIFT)
#define TILE_MASK (TILE_SIZE - 1)

static unsigned int gbe_mem_size = CONFIG_FB_GBE_MEM * 1024*1024;
static void *gbe_mem;
static dma_addr_t gbe_dma_addr;
static unsigned long gbe_mem_phys;

static struct {
	uint16_t *cpu;
	dma_addr_t dma;
} gbe_tiles;

static int gbe_revision;

static int ypan, ywrap;

static uint32_t pseudo_palette[16];
static uint32_t gbe_cmap[256];
static int gbe_turned_on; /* 0 turned off, 1 turned on */

static char *mode_option = NULL;

/* default CRT mode */
static struct fb_var_screeninfo default_var_CRT = {
	/* 640x480, 60 Hz, Non-Interlaced (25.175 MHz dotclock) */
	.xres		= 640,
	.yres		= 480,
	.xres_virtual	= 640,
	.yres_virtual	= 480,
	.xoffset	= 0,
	.yoffset	= 0,
	.bits_per_pixel	= 8,
	.grayscale	= 0,
	.red		= { 0, 8, 0 },
	.green		= { 0, 8, 0 },
	.blue		= { 0, 8, 0 },
	.transp		= { 0, 0, 0 },
	.nonstd		= 0,
	.activate	= 0,
	.height		= -1,
	.width		= -1,
	.accel_flags	= 0,
	.pixclock	= 39722,	/* picoseconds */
	.left_margin	= 48,
	.right_margin	= 16,
	.upper_margin	= 33,
	.lower_margin	= 10,
	.hsync_len	= 96,
	.vsync_len	= 2,
	.sync		= 0,
	.vmode		= FB_VMODE_NONINTERLACED,
};

/* default LCD mode */
static struct fb_var_screeninfo default_var_LCD = {
	/* 1600x1024, 8 bpp */
	.xres		= 1600,
	.yres		= 1024,
	.xres_virtual	= 1600,
	.yres_virtual	= 1024,
	.xoffset	= 0,
	.yoffset	= 0,
	.bits_per_pixel	= 8,
	.grayscale	= 0,
	.red		= { 0, 8, 0 },
	.green		= { 0, 8, 0 },
	.blue		= { 0, 8, 0 },
	.transp		= { 0, 0, 0 },
	.nonstd		= 0,
	.activate	= 0,
	.height		= -1,
	.width		= -1,
	.accel_flags	= 0,
	.pixclock	= 9353,
	.left_margin	= 20,
	.right_margin	= 30,
	.upper_margin	= 37,
	.lower_margin	= 3,
	.hsync_len	= 20,
	.vsync_len	= 3,
	.sync		= 0,
	.vmode		= FB_VMODE_NONINTERLACED
};

/* default modedb mode */
/* 640x480, 60 Hz, Non-Interlaced (25.172 MHz dotclock) */
static struct fb_videomode default_mode_CRT = {
	.refresh	= 60,
	.xres		= 640,
	.yres		= 480,
	.pixclock	= 39722,
	.left_margin	= 48,
	.right_margin	= 16,
	.upper_margin	= 33,
	.lower_margin	= 10,
	.hsync_len	= 96,
	.vsync_len	= 2,
	.sync		= 0,
	.vmode		= FB_VMODE_NONINTERLACED,
};
/* 1600x1024 SGI flatpanel 1600sw */
static struct fb_videomode default_mode_LCD = {
	/* 1600x1024, 8 bpp */
	.xres		= 1600,
	.yres		= 1024,
	.pixclock	= 9353,
	.left_margin	= 20,
	.right_margin	= 30,
	.upper_margin	= 37,
	.lower_margin	= 3,
	.hsync_len	= 20,
	.vsync_len	= 3,
	.vmode		= FB_VMODE_NONINTERLACED,
};

static struct fb_videomode *default_mode = &default_mode_CRT;
static struct fb_var_screeninfo *default_var = &default_var_CRT;

static int flat_panel_enabled = 0;

static void gbe_reset(void)
{
	/* Turn on dotclock PLL */
	gbe->ctrlstat = 0x300aa000;
}


/*
 * Function:	gbe_turn_off
 * Parameters:	(None)
 * Description:	This should turn off the monitor and gbe.  This is used
 *              when switching between the serial console and the graphics
 *              console.
 */

static void gbe_turn_off(void)
{
	int i;
	unsigned int val, x, y, vpixen_off;

	gbe_turned_on = 0;

	/* check if pixel counter is on */
	val = gbe->vt_xy;
	if (GET_GBE_FIELD(VT_XY, FREEZE, val) == 1)
		return;

	/* turn off DMA */
	val = gbe->ovr_control;
	SET_GBE_FIELD(OVR_CONTROL, OVR_DMA_ENABLE, val, 0);
	gbe->ovr_control = val;
	udelay(1000);
	val = gbe->frm_control;
	SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 0);
	gbe->frm_control = val;
	udelay(1000);
	val = gbe->did_control;
	SET_GBE_FIELD(DID_CONTROL, DID_DMA_ENABLE, val, 0);
	gbe->did_control = val;
	udelay(1000);

	/* We have to wait through two vertical retrace periods before
	 * the pixel DMA is turned off for sure. */
	for (i = 0; i < 10000; i++) {
		val = gbe->frm_inhwctrl;
		if (GET_GBE_FIELD(FRM_INHWCTRL, FRM_DMA_ENABLE, val)) {
			udelay(10);
		} else {
			val = gbe->ovr_inhwctrl;
			if (GET_GBE_FIELD(OVR_INHWCTRL, OVR_DMA_ENABLE, val)) {
				udelay(10);
			} else {
				val = gbe->did_inhwctrl;
				if (GET_GBE_FIELD(DID_INHWCTRL, DID_DMA_ENABLE, val)) {
					udelay(10);
				} else
					break;
			}
		}
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn off DMA timed out\n");

	/* wait for vpixen_off */
	val = gbe->vt_vpixen;
	vpixen_off = GET_GBE_FIELD(VT_VPIXEN, VPIXEN_OFF, val);

	for (i = 0; i < 100000; i++) {
		val = gbe->vt_xy;
		x = GET_GBE_FIELD(VT_XY, X, val);
		y = GET_GBE_FIELD(VT_XY, Y, val);
		if (y < vpixen_off)
			break;
		udelay(1);
	}
	if (i == 100000)
		printk(KERN_ERR
		       "gbefb: wait for vpixen_off timed out\n");
	for (i = 0; i < 10000; i++) {
		val = gbe->vt_xy;
		x = GET_GBE_FIELD(VT_XY, X, val);
		y = GET_GBE_FIELD(VT_XY, Y, val);
		if (y > vpixen_off)
			break;
		udelay(1);
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: wait for vpixen_off timed out\n");

	/* turn off pixel counter */
	val = 0;
	SET_GBE_FIELD(VT_XY, FREEZE, val, 1);
	gbe->vt_xy = val;
	udelay(10000);
	for (i = 0; i < 10000; i++) {
		val = gbe->vt_xy;
		if (GET_GBE_FIELD(VT_XY, FREEZE, val) != 1)
			udelay(10);
		else
			break;
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn off pixel clock timed out\n");

	/* turn off dot clock */
	val = gbe->dotclock;
	SET_GBE_FIELD(DOTCLK, RUN, val, 0);
	gbe->dotclock = val;
	udelay(10000);
	for (i = 0; i < 10000; i++) {
		val = gbe->dotclock;
		if (GET_GBE_FIELD(DOTCLK, RUN, val))
			udelay(10);
		else
			break;
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn off dotclock timed out\n");

	/* reset the frame DMA FIFO */
	val = gbe->frm_size_tile;
	SET_GBE_FIELD(FRM_SIZE_TILE, FRM_FIFO_RESET, val, 1);
	gbe->frm_size_tile = val;
	SET_GBE_FIELD(FRM_SIZE_TILE, FRM_FIFO_RESET, val, 0);
	gbe->frm_size_tile = val;
}

static void gbe_turn_on(void)
{
	unsigned int val, i;

	/*
	 * Check if pixel counter is off, for unknown reason this
	 * code hangs Visual Workstations
	 */
	if (gbe_revision < 2) {
		val = gbe->vt_xy;
		if (GET_GBE_FIELD(VT_XY, FREEZE, val) == 0)
			return;
	}

	/* turn on dot clock */
	val = gbe->dotclock;
	SET_GBE_FIELD(DOTCLK, RUN, val, 1);
	gbe->dotclock = val;
	udelay(10000);
	for (i = 0; i < 10000; i++) {
		val = gbe->dotclock;
		if (GET_GBE_FIELD(DOTCLK, RUN, val) != 1)
			udelay(10);
		else
			break;
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn on dotclock timed out\n");

	/* turn on pixel counter */
	val = 0;
	SET_GBE_FIELD(VT_XY, FREEZE, val, 0);
	gbe->vt_xy = val;
	udelay(10000);
	for (i = 0; i < 10000; i++) {
		val = gbe->vt_xy;
		if (GET_GBE_FIELD(VT_XY, FREEZE, val))
			udelay(10);
		else
			break;
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn on pixel clock timed out\n");

	/* turn on DMA */
	val = gbe->frm_control;
	SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 1);
	gbe->frm_control = val;
	udelay(1000);
	for (i = 0; i < 10000; i++) {
		val = gbe->frm_inhwctrl;
		if (GET_GBE_FIELD(FRM_INHWCTRL, FRM_DMA_ENABLE, val) != 1)
			udelay(10);
		else
			break;
	}
	if (i == 10000)
		printk(KERN_ERR "gbefb: turn on DMA timed out\n");

	gbe_turned_on = 1;
}

static void gbe_loadcmap(void)
{
	int i, j;

	for (i = 0; i < 256; i++) {
		for (j = 0; j < 1000 && gbe->cm_fifo >= 63; j++)
			udelay(10);
		if (j == 1000)
			printk(KERN_ERR "gbefb: cmap FIFO timeout\n");

		gbe->cmap[i] = gbe_cmap[i];
	}
}

/*
 *  Blank the display.
 */
static int gbefb_blank(int blank, struct fb_info *info)
{
	/* 0 unblank, 1 blank, 2 no vsync, 3 no hsync, 4 off */
	switch (blank) {
	case FB_BLANK_UNBLANK:		/* unblank */
		gbe_turn_on();
		gbe_loadcmap();
		break;

	case FB_BLANK_NORMAL:		/* blank */
		gbe_turn_off();
		break;

	default:
		/* Nothing */
		break;
	}
	return 0;
}

/*
 *  Setup flatpanel related registers.
 */
static void gbefb_setup_flatpanel(struct gbe_timing_info *timing)
{
	int fp_wid, fp_hgt, fp_vbs, fp_vbe;
	u32 outputVal = 0;

	SET_GBE_FIELD(VT_FLAGS, HDRV_INVERT, outputVal,
		(timing->flags & FB_SYNC_HOR_HIGH_ACT) ? 0 : 1);
	SET_GBE_FIELD(VT_FLAGS, VDRV_INVERT, outputVal,
		(timing->flags & FB_SYNC_VERT_HIGH_ACT) ? 0 : 1);
	gbe->vt_flags = outputVal;

	/* Turn on the flat panel */
	fp_wid = 1600;
	fp_hgt = 1024;
	fp_vbs = 0;
	fp_vbe = 1600;
	timing->pll_m = 4;
	timing->pll_n = 1;
	timing->pll_p = 0;

	outputVal = 0;
	SET_GBE_FIELD(FP_DE, ON, outputVal, fp_vbs);
	SET_GBE_FIELD(FP_DE, OFF, outputVal, fp_vbe);
	gbe->fp_de = outputVal;
	outputVal = 0;
	SET_GBE_FIELD(FP_HDRV, OFF, outputVal, fp_wid);
	gbe->fp_hdrv = outputVal;
	outputVal = 0;
	SET_GBE_FIELD(FP_VDRV, ON, outputVal, 1);
	SET_GBE_FIELD(FP_VDRV, OFF, outputVal, fp_hgt + 1);
	gbe->fp_vdrv = outputVal;
}

struct gbe_pll_info {
	int clock_rate;
	int fvco_min;
	int fvco_max;
};

static struct gbe_pll_info gbe_pll_table[2] = {
	{ 20, 80, 220 },
	{ 27, 80, 220 },
};

static int compute_gbe_timing(struct fb_var_screeninfo *var,
			      struct gbe_timing_info *timing)
{
	int pll_m, pll_n, pll_p, error, best_m, best_n, best_p, best_error;
	int pixclock;
	struct gbe_pll_info *gbe_pll;

	if (gbe_revision < 2)
		gbe_pll = &gbe_pll_table[0];
	else
		gbe_pll = &gbe_pll_table[1];

	/* Determine valid resolution and timing
	 * GBE crystal runs at 20Mhz or 27Mhz
	 * pll_m, pll_n, pll_p define the following frequencies
	 * fvco = pll_m * 20Mhz / pll_n
	 * fout = fvco / (2**pll_p) */
	best_error = 1000000000;
	best_n = best_m = best_p = 0;
	for (pll_p = 0; pll_p < 4; pll_p++)
		for (pll_m = 1; pll_m < 256; pll_m++)
			for (pll_n = 1; pll_n < 64; pll_n++) {
				pixclock = (1000000 / gbe_pll->clock_rate) *
						(pll_n << pll_p) / pll_m;

				error = var->pixclock - pixclock;

				if (error < 0)
					error = -error;

				if (error < best_error &&
				    pll_m / pll_n >
				    gbe_pll->fvco_min / gbe_pll->clock_rate &&
 				    pll_m / pll_n <
				    gbe_pll->fvco_max / gbe_pll->clock_rate) {
					best_error = error;
					best_m = pll_m;
					best_n = pll_n;
					best_p = pll_p;
				}
			}

	if (!best_n || !best_m)
		return -EINVAL;	/* Resolution to high */

	pixclock = (1000000 / gbe_pll->clock_rate) *
		(best_n << best_p) / best_m;

	/* set video timing information */
	if (timing) {
		timing->width = var->xres;
		timing->height = var->yres;
		timing->pll_m = best_m;
		timing->pll_n = best_n;
		timing->pll_p = best_p;
		timing->cfreq = gbe_pll->clock_rate * 1000 * timing->pll_m /
			(timing->pll_n << timing->pll_p);
		timing->htotal = var->left_margin + var->xres +
				var->right_margin + var->hsync_len;
		timing->vtotal = var->upper_margin + var->yres +
				var->lower_margin + var->vsync_len;
		timing->fields_sec = 1000 * timing->cfreq / timing->htotal *
				1000 / timing->vtotal;
		timing->hblank_start = var->xres;
		timing->vblank_start = var->yres;
		timing->hblank_end = timing->htotal;
		timing->hsync_start = var->xres + var->right_margin + 1;
		timing->hsync_end = timing->hsync_start + var->hsync_len;
		timing->vblank_end = timing->vtotal;
		timing->vsync_start = var->yres + var->lower_margin + 1;
		timing->vsync_end = timing->vsync_start + var->vsync_len;
	}

	return pixclock;
}

static void gbe_set_timing_info(struct gbe_timing_info *timing)
{
	int temp;
	unsigned int val;

	/* setup dot clock PLL */
	val = 0;
	SET_GBE_FIELD(DOTCLK, M, val, timing->pll_m - 1);
	SET_GBE_FIELD(DOTCLK, N, val, timing->pll_n - 1);
	SET_GBE_FIELD(DOTCLK, P, val, timing->pll_p);
	SET_GBE_FIELD(DOTCLK, RUN, val, 0);	/* do not start yet */
	gbe->dotclock = val;
	udelay(10000);

	/* setup pixel counter */
	val = 0;
	SET_GBE_FIELD(VT_XYMAX, MAXX, val, timing->htotal);
	SET_GBE_FIELD(VT_XYMAX, MAXY, val, timing->vtotal);
	gbe->vt_xymax = val;

	/* setup video timing signals */
	val = 0;
	SET_GBE_FIELD(VT_VSYNC, VSYNC_ON, val, timing->vsync_start);
	SET_GBE_FIELD(VT_VSYNC, VSYNC_OFF, val, timing->vsync_end);
	gbe->vt_vsync = val;
	val = 0;
	SET_GBE_FIELD(VT_HSYNC, HSYNC_ON, val, timing->hsync_start);
	SET_GBE_FIELD(VT_HSYNC, HSYNC_OFF, val, timing->hsync_end);
	gbe->vt_hsync = val;
	val = 0;
	SET_GBE_FIELD(VT_VBLANK, VBLANK_ON, val, timing->vblank_start);
	SET_GBE_FIELD(VT_VBLANK, VBLANK_OFF, val, timing->vblank_end);
	gbe->vt_vblank = val;
	val = 0;
	SET_GBE_FIELD(VT_HBLANK, HBLANK_ON, val,
		      timing->hblank_start - 5);
	SET_GBE_FIELD(VT_HBLANK, HBLANK_OFF, val,
		      timing->hblank_end - 3);
	gbe->vt_hblank = val;

	/* setup internal timing signals */
	val = 0;
	SET_GBE_FIELD(VT_VCMAP, VCMAP_ON, val, timing->vblank_start);
	SET_GBE_FIELD(VT_VCMAP, VCMAP_OFF, val, timing->vblank_end);
	gbe->vt_vcmap = val;
	val = 0;
	SET_GBE_FIELD(VT_HCMAP, HCMAP_ON, val, timing->hblank_start);
	SET_GBE_FIELD(VT_HCMAP, HCMAP_OFF, val, timing->hblank_end);
	gbe->vt_hcmap = val;

	val = 0;
	temp = timing->vblank_start - timing->vblank_end - 1;
	if (temp > 0)
		temp = -temp;

	if (flat_panel_enabled)
		gbefb_setup_flatpanel(timing);

	SET_GBE_FIELD(DID_START_XY, DID_STARTY, val, (u32) temp);
	if (timing->hblank_end >= 20)
		SET_GBE_FIELD(DID_START_XY, DID_STARTX, val,
			      timing->hblank_end - 20);
	else
		SET_GBE_FIELD(DID_START_XY, DID_STARTX, val,
			      timing->htotal - (20 - timing->hblank_end));
	gbe->did_start_xy = val;

	val = 0;
	SET_GBE_FIELD(CRS_START_XY, CRS_STARTY, val, (u32) (temp + 1));
	if (timing->hblank_end >= GBE_CRS_MAGIC)
		SET_GBE_FIELD(CRS_START_XY, CRS_STARTX, val,
			      timing->hblank_end - GBE_CRS_MAGIC);
	else
		SET_GBE_FIELD(CRS_START_XY, CRS_STARTX, val,
			      timing->htotal - (GBE_CRS_MAGIC -
						timing->hblank_end));
	gbe->crs_start_xy = val;

	val = 0;
	SET_GBE_FIELD(VC_START_XY, VC_STARTY, val, (u32) temp);
	SET_GBE_FIELD(VC_START_XY, VC_STARTX, val, timing->hblank_end - 4);
	gbe->vc_start_xy = val;

	val = 0;
	temp = timing->hblank_end - GBE_PIXEN_MAGIC_ON;
	if (temp < 0)
		temp += timing->htotal;	/* allow blank to wrap around */

	SET_GBE_FIELD(VT_HPIXEN, HPIXEN_ON, val, temp);
	SET_GBE_FIELD(VT_HPIXEN, HPIXEN_OFF, val,
		      ((temp + timing->width -
			GBE_PIXEN_MAGIC_OFF) % timing->htotal));
	gbe->vt_hpixen = val;

	val = 0;
	SET_GBE_FIELD(VT_VPIXEN, VPIXEN_ON, val, timing->vblank_end);
	SET_GBE_FIELD(VT_VPIXEN, VPIXEN_OFF, val, timing->vblank_start);
	gbe->vt_vpixen = val;

	/* turn off sync on green */
	val = 0;
	SET_GBE_FIELD(VT_FLAGS, SYNC_LOW, val, 1);
	gbe->vt_flags = val;
}

/*
 *  Set the hardware according to 'par'.
 */

static int gbefb_set_par(struct fb_info *info)
{
	int i;
	unsigned int val;
	int wholeTilesX, partTilesX, maxPixelsPerTileX;
	int height_pix;
	int xpmax, ypmax;	/* Monitor resolution */
	int bytesPerPixel;	/* Bytes per pixel */
	struct gbefb_par *par = (struct gbefb_par *) info->par;

	compute_gbe_timing(&info->var, &par->timing);

	bytesPerPixel = info->var.bits_per_pixel / 8;
	info->fix.line_length = info->var.xres_virtual * bytesPerPixel;
	xpmax = par->timing.width;
	ypmax = par->timing.height;

	/* turn off GBE */
	gbe_turn_off();

	/* set timing info */
	gbe_set_timing_info(&par->timing);

	/* initialize DIDs */
	val = 0;
	switch (bytesPerPixel) {
	case 1:
		SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_I8);
		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
		break;
	case 2:
		SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_ARGB5);
		info->fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	case 4:
		SET_GBE_FIELD(WID, TYP, val, GBE_CMODE_RGB8);
		info->fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	}
	SET_GBE_FIELD(WID, BUF, val, GBE_BMODE_BOTH);

	for (i = 0; i < 32; i++)
		gbe->mode_regs[i] = val;

	/* Initialize interrupts */
	gbe->vt_intr01 = 0xffffffff;
	gbe->vt_intr23 = 0xffffffff;

	/* HACK:
	   The GBE hardware uses a tiled memory to screen mapping. Tiles are
	   blocks of 512x128, 256x128 or 128x128 pixels, respectively for 8bit,
	   16bit and 32 bit modes (64 kB). They cover the screen with partial
	   tiles on the right and/or bottom of the screen if needed.
	   For example in 640x480 8 bit mode the mapping is:

	   <-------- 640 ----->
	   <---- 512 ----><128|384 offscreen>
	   ^  ^
	   | 128    [tile 0]        [tile 1]
	   |  v
	   ^
	   4 128    [tile 2]        [tile 3]
	   8  v
	   0  ^
	   128    [tile 4]        [tile 5]
	   |  v
	   |  ^
	   v  96    [tile 6]        [tile 7]
	   32 offscreen

	   Tiles have the advantage that they can be allocated individually in
	   memory. However, this mapping is not linear at all, which is not
	   really convenient. In order to support linear addressing, the GBE
	   DMA hardware is fooled into thinking the screen is only one tile
	   large and but has a greater height, so that the DMA transfer covers
	   the same region.
	   Tiles are still allocated as independent chunks of 64KB of
	   continuous physical memory and remapped so that the kernel sees the
	   framebuffer as a continuous virtual memory. The GBE tile table is
	   set up so that each tile references one of these 64k blocks:

	   GBE -> tile list    framebuffer           TLB   <------------ CPU
	          [ tile 0 ] -> [ 64KB ]  <- [ 16x 4KB page entries ]     ^
	             ...           ...              ...       linear virtual FB
	          [ tile n ] -> [ 64KB ]  <- [ 16x 4KB page entries ]     v


	   The GBE hardware is then told that the buffer is 512*tweaked_height,
	   with tweaked_height = real_width*real_height/pixels_per_tile.
	   Thus the GBE hardware will scan the first tile, filing the first 64k
	   covered region of the screen, and then will proceed to the next
	   tile, until the whole screen is covered.

	   Here is what would happen at 640x480 8bit:

	   normal tiling               linear
	   ^   11111111111111112222    11111111111111111111  ^
	   128 11111111111111112222    11111111111111111111 102 lines
	       11111111111111112222    11111111111111111111  v
	   V   11111111111111112222    11111111222222222222
	       33333333333333334444    22222222222222222222
	       33333333333333334444    22222222222222222222
	       <      512     >        <  256 >               102*640+256 = 64k

	   NOTE: The only mode for which this is not working is 800x600 8bit,
	   as 800*600/512 = 937.5 which is not integer and thus causes
	   flickering.
	   I guess this is not so important as one can use 640x480 8bit or
	   800x600 16bit anyway.
	 */

	/* Tell gbe about the tiles table location */
	/* tile_ptr -> [ tile 1 ] -> FB mem */
	/*             [ tile 2 ] -> FB mem */
	/*               ...                */
	val = 0;
	SET_GBE_FIELD(FRM_CONTROL, FRM_TILE_PTR, val, gbe_tiles.dma >> 9);
	SET_GBE_FIELD(FRM_CONTROL, FRM_DMA_ENABLE, val, 0); /* do not start */
	SET_GBE_FIELD(FRM_CONTROL, FRM_LINEAR, val, 0);
	gbe->frm_control = val;

	maxPixelsPerTileX = 512 / bytesPerPixel;
	wholeTilesX = 1;
	partTilesX = 0;

	/* Initialize the framebuffer */
	val = 0;
	SET_GBE_FIELD(FRM_SIZE_TILE, FRM_WIDTH_TILE, val, wholeTilesX);
	SET_GBE_FIELD(FRM_SIZE_TILE, FRM_RHS, val, partTilesX);

	switch (bytesPerPixel) {
	case 1:
		SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,
			      GBE_FRM_DEPTH_8);
		break;
	case 2:
		SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,
			      GBE_FRM_DEPTH_16);
		break;
	case 4:
		SET_GBE_FIELD(FRM_SIZE_TILE, FRM_DEPTH, val,
			      GBE_FRM_DEPTH_32);
		break;
	}
	gbe->frm_size_tile = val;

	/* compute tweaked height */
	height_pix = xpmax * ypmax / maxPixelsPerTileX;

	val = 0;
	SET_GBE_FIELD(FRM_SIZE_PIXEL, FB_HEIGHT_PIX, val, height_pix);
	gbe->frm_size_pixel = val;

	/* turn off DID and overlay DMA */
	gbe->did_control = 0;
	gbe->ovr_width_tile = 0;

	/* Turn off mouse cursor */
	gbe->crs_ctl = 0;

	/* Turn on GBE */
	gbe_turn_on();

	/* Initialize the gamma map */
	udelay(10);
	for (i = 0; i < 256; i++)
		gbe->gmap[i] = (i << 24) | (i << 16) | (i << 8);

	/* Initialize the color map */
	for (i = 0; i < 256; i++)
		gbe_cmap[i] = (i << 8) | (i << 16) | (i << 24);

	gbe_loadcmap();

	return 0;
}

static void gbefb_encode_fix(struct fb_fix_screeninfo *fix,
			     struct fb_var_screeninfo *var)
{
	memset(fix, 0, sizeof(struct fb_fix_screeninfo));
	strcpy(fix->id, "SGI GBE");
	fix->smem_start = (unsigned long) gbe_mem;
	fix->smem_len = gbe_mem_size;
	fix->type = FB_TYPE_PACKED_PIXELS;
	fix->type_aux = 0;
	fix->accel = FB_ACCEL_NONE;
	switch (var->bits_per_pixel) {
	case 8:
		fix->visual = FB_VISUAL_PSEUDOCOLOR;
		break;
	default:
		fix->visual = FB_VISUAL_TRUECOLOR;
		break;
	}
	fix->ywrapstep = 0;
	fix->xpanstep = 0;
	fix->ypanstep = 0;
	fix->line_length = var->xres_virtual * var->bits_per_pixel / 8;
	fix->mmio_start = GBE_BASE;
	fix->mmio_len = sizeof(struct sgi_gbe);
}

/*
 *  Set a single color register. The values supplied are already
 *  rounded down to the hardware's capabilities (according to the
 *  entries in the var structure). Return != 0 for invalid regno.
 */

static int gbefb_setcolreg(unsigned regno, unsigned red, unsigned green,
			     unsigned blue, unsigned transp,
			     struct fb_info *info)
{
	int i;

	if (regno > 255)
		return 1;
	red >>= 8;
	green >>= 8;
	blue >>= 8;

	if (info->var.bits_per_pixel <= 8) {
		gbe_cmap[regno] = (red << 24) | (green << 16) | (blue << 8);
		if (gbe_turned_on) {
			/* wait for the color map FIFO to have a free entry */
			for (i = 0; i < 1000 && gbe->cm_fifo >= 63; i++)
				udelay(10);
			if (i == 1000) {
				printk(KERN_ERR "gbefb: cmap FIFO timeout\n");
				return 1;
			}
			gbe->cmap[regno] = gbe_cmap[regno];
		}
	} else if (regno < 16) {
		switch (info->var.bits_per_pixel) {
		case 15:
		case 16:
			red >>= 3;
			green >>= 3;
			blue >>= 3;
			pseudo_palette[regno] =
				(red << info->var.red.offset) |
				(green << info->var.green.offset) |
				(blue << info->var.blue.offset);
			break;
		case 32:
			pseudo_palette[regno] =
				(red << info->var.red.offset) |
				(green << info->var.green.offset) |
				(blue << info->var.blue.offset);
			break;
		}
	}

	return 0;
}

/*
 *  Check video mode validity, eventually modify var to best match.
 */
static int gbefb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
	unsigned int line_length;
	struct gbe_timing_info timing;
	int ret;

	/* Limit bpp to 8, 16, and 32 */
	if (var->bits_per_pixel <= 8)
		var->bits_per_pixel = 8;
	else if (var->bits_per_pixel <= 16)
		var->bits_per_pixel = 16;
	else if (var->bits_per_pixel <= 32)
		var->bits_per_pixel = 32;
	else
		return -EINVAL;

	/* Check the mode can be mapped linearly with the tile table trick. */
	/* This requires width x height x bytes/pixel be a multiple of 512 */
	if ((var->xres * var->yres * var->bits_per_pixel) & 4095)
		return -EINVAL;

	var->grayscale = 0;	/* No grayscale for now */

	ret = compute_gbe_timing(var, &timing);
	var->pixclock = ret;
	if (ret < 0)
		return -EINVAL;

	/* Adjust virtual resolution, if necessary */
	if (var->xres > var->xres_virtual || (!ywrap && !ypan))
		var->xres_virtual = var->xres;
	if (var->yres > var->yres_virtual || (!ywrap && !ypan))
		var->yres_virtual = var->yres;

	if (var->vmode & FB_VMODE_CONUPDATE) {
		var->vmode |= FB_VMODE_YWRAP;
		var->xoffset = info->var.xoffset;
		var->yoffset = info->var.yoffset;
	}

	/* No grayscale for now */
	var->grayscale = 0;

	/* Memory limit */
	line_length = var->xres_virtual * var->bits_per_pixel / 8;
	if (line_length * var->yres_virtual > gbe_mem_size)
		return -ENOMEM;	/* Virtual resolution too high */

	switch (var->bits_per_pixel) {
	case 8:
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 0;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 16:		/* RGB 1555 */
		var->red.offset = 10;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 5;
		var->blue.offset = 0;
		var->blue.length = 5;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 32:		/* RGB 8888 */
		var->red.offset = 24;
		var->red.length = 8;
		var->green.offset = 16;
		var->green.length = 8;
		var->blue.offset = 8;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 8;
		break;
	}
	var->red.msb_right = 0;
	var->green.msb_right = 0;
	var->blue.msb_right = 0;
	var->transp.msb_right = 0;

	var->left_margin = timing.htotal - timing.hsync_end;
	var->right_margin = timing.hsync_start - timing.width;
	var->upper_margin = timing.vtotal - timing.vsync_end;
	var->lower_margin = timing.vsync_start - timing.height;
	var->hsync_len = timing.hsync_end - timing.hsync_start;
	var->vsync_len = timing.vsync_end - timing.vsync_start;

	return 0;
}

static int gbefb_mmap(struct fb_info *info,
			struct vm_area_struct *vma)
{
	unsigned long size = vma->vm_end - vma->vm_start;
	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
	unsigned long addr;
	unsigned long phys_addr, phys_size;
	u16 *tile;

	/* check range */
	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
		return -EINVAL;
	if (size > gbe_mem_size)
		return -EINVAL;
	if (offset > gbe_mem_size - size)
		return -EINVAL;

	/* remap using the fastest write-through mode on architecture */
	/* try not polluting the cache when possible */
	pgprot_val(vma->vm_page_prot) =
		pgprot_fb(pgprot_val(vma->vm_page_prot));

	/* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */

	/* look for the starting tile */
	tile = &gbe_tiles.cpu[offset >> TILE_SHIFT];
	addr = vma->vm_start;
	offset &= TILE_MASK;

	/* remap each tile separately */
	do {
		phys_addr = (((unsigned long) (*tile)) << TILE_SHIFT) + offset;
		if ((offset + size) < TILE_SIZE)
			phys_size = size;
		else
			phys_size = TILE_SIZE - offset;

		if (remap_pfn_range(vma, addr, phys_addr >> PAGE_SHIFT,
						phys_size, vma->vm_page_prot))
			return -EAGAIN;

		offset = 0;
		size -= phys_size;
		addr += phys_size;
		tile++;
	} while (size);

	return 0;
}

static struct fb_ops gbefb_ops = {
	.owner		= THIS_MODULE,
	.fb_check_var	= gbefb_check_var,
	.fb_set_par	= gbefb_set_par,
	.fb_setcolreg	= gbefb_setcolreg,
	.fb_mmap	= gbefb_mmap,
	.fb_blank	= gbefb_blank,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

/*
 * sysfs
 */

static ssize_t gbefb_show_memsize(struct device *dev, struct device_attribute *attr, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%u\n", gbe_mem_size);
}

static DEVICE_ATTR(size, S_IRUGO, gbefb_show_memsize, NULL);

static ssize_t gbefb_show_rev(struct device *device, struct device_attribute *attr, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", gbe_revision);
}

static DEVICE_ATTR(revision, S_IRUGO, gbefb_show_rev, NULL);

static void gbefb_remove_sysfs(struct device *dev)
{
	device_remove_file(dev, &dev_attr_size);
	device_remove_file(dev, &dev_attr_revision);
}

static void gbefb_create_sysfs(struct device *dev)
{
	device_create_file(dev, &dev_attr_size);
	device_create_file(dev, &dev_attr_revision);
}

/*
 * Initialization
 */

static int gbefb_setup(char *options)
{
	char *this_opt;

	if (!options || !*options)
		return 0;

	while ((this_opt = strsep(&options, ",")) != NULL) {
		if (!strncmp(this_opt, "monitor:", 8)) {
			if (!strncmp(this_opt + 8, "crt", 3)) {
				flat_panel_enabled = 0;
				default_var = &default_var_CRT;
				default_mode = &default_mode_CRT;
			} else if (!strncmp(this_opt + 8, "1600sw", 6) ||
				   !strncmp(this_opt + 8, "lcd", 3)) {
				flat_panel_enabled = 1;
				default_var = &default_var_LCD;
				default_mode = &default_mode_LCD;
			}
		} else if (!strncmp(this_opt, "mem:", 4)) {
			gbe_mem_size = memparse(this_opt + 4, &this_opt);
			if (gbe_mem_size > CONFIG_FB_GBE_MEM * 1024 * 1024)
				gbe_mem_size = CONFIG_FB_GBE_MEM * 1024 * 1024;
			if (gbe_mem_size < TILE_SIZE)
				gbe_mem_size = TILE_SIZE;
		} else
			mode_option = this_opt;
	}
	return 0;
}

static int gbefb_probe(struct platform_device *p_dev)
{
	int i, ret = 0;
	struct fb_info *info;
	struct gbefb_par *par;
#ifndef MODULE
	char *options = NULL;
#endif

	info = framebuffer_alloc(sizeof(struct gbefb_par), &p_dev->dev);
	if (!info)
		return -ENOMEM;

#ifndef MODULE
	if (fb_get_options("gbefb", &options)) {
		ret = -ENODEV;
		goto out_release_framebuffer;
	}
	gbefb_setup(options);
#endif

	if (!request_mem_region(GBE_BASE, sizeof(struct sgi_gbe), "GBE")) {
		printk(KERN_ERR "gbefb: couldn't reserve mmio region\n");
		ret = -EBUSY;
		goto out_release_framebuffer;
	}

	gbe = (struct sgi_gbe *) devm_ioremap(&p_dev->dev, GBE_BASE,
					      sizeof(struct sgi_gbe));
	if (!gbe) {
		printk(KERN_ERR "gbefb: couldn't map mmio region\n");
		ret = -ENXIO;
		goto out_release_mem_region;
	}
	gbe_revision = gbe->ctrlstat & 15;

	gbe_tiles.cpu =
		dma_alloc_coherent(NULL, GBE_TLB_SIZE * sizeof(uint16_t),
				   &gbe_tiles.dma, GFP_KERNEL);
	if (!gbe_tiles.cpu) {
		printk(KERN_ERR "gbefb: couldn't allocate tiles table\n");
		ret = -ENOMEM;
		goto out_release_mem_region;
	}

	if (gbe_mem_phys) {
		/* memory was allocated at boot time */
		gbe_mem = devm_ioremap_wc(&p_dev->dev, gbe_mem_phys,
					  gbe_mem_size);
		if (!gbe_mem) {
			printk(KERN_ERR "gbefb: couldn't map framebuffer\n");
			ret = -ENOMEM;
			goto out_tiles_free;
		}

		gbe_dma_addr = 0;
	} else {
		/* try to allocate memory with the classical allocator
		 * this has high chance to fail on low memory machines */
		gbe_mem = dma_alloc_writecombine(NULL, gbe_mem_size,
						 &gbe_dma_addr, GFP_KERNEL);
		if (!gbe_mem) {
			printk(KERN_ERR "gbefb: couldn't allocate framebuffer memory\n");
			ret = -ENOMEM;
			goto out_tiles_free;
		}

		gbe_mem_phys = (unsigned long) gbe_dma_addr;
	}

	par = info->par;
	par->wc_cookie = arch_phys_wc_add(gbe_mem_phys, gbe_mem_size);

	/* map framebuffer memory into tiles table */
	for (i = 0; i < (gbe_mem_size >> TILE_SHIFT); i++)
		gbe_tiles.cpu[i] = (gbe_mem_phys >> TILE_SHIFT) + i;

	info->fbops = &gbefb_ops;
	info->pseudo_palette = pseudo_palette;
	info->flags = FBINFO_DEFAULT;
	info->screen_base = gbe_mem;
	fb_alloc_cmap(&info->cmap, 256, 0);

	/* reset GBE */
	gbe_reset();

	/* turn on default video mode */
	if (fb_find_mode(&par->var, info, mode_option, NULL, 0,
			 default_mode, 8) == 0)
		par->var = *default_var;
	info->var = par->var;
	gbefb_check_var(&par->var, info);
	gbefb_encode_fix(&info->fix, &info->var);

	if (register_framebuffer(info) < 0) {
		printk(KERN_ERR "gbefb: couldn't register framebuffer\n");
		ret = -ENXIO;
		goto out_gbe_unmap;
	}

	platform_set_drvdata(p_dev, info);
	gbefb_create_sysfs(&p_dev->dev);

	fb_info(info, "%s rev %d @ 0x%08x using %dkB memory\n",
		info->fix.id, gbe_revision, (unsigned)GBE_BASE,
		gbe_mem_size >> 10);

	return 0;

out_gbe_unmap:
	arch_phys_wc_del(par->wc_cookie);
	if (gbe_dma_addr)
		dma_free_writecombine(NULL, gbe_mem_size, gbe_mem, gbe_mem_phys);
out_tiles_free:
	dma_free_coherent(NULL, GBE_TLB_SIZE * sizeof(uint16_t),
			  (void *)gbe_tiles.cpu, gbe_tiles.dma);
out_release_mem_region:
	release_mem_region(GBE_BASE, sizeof(struct sgi_gbe));
out_release_framebuffer:
	framebuffer_release(info);

	return ret;
}

static int gbefb_remove(struct platform_device* p_dev)
{
	struct fb_info *info = platform_get_drvdata(p_dev);
	struct gbefb_par *par = info->par;

	unregister_framebuffer(info);
	gbe_turn_off();
	arch_phys_wc_del(par->wc_cookie);
	if (gbe_dma_addr)
		dma_free_writecombine(NULL, gbe_mem_size, gbe_mem, gbe_mem_phys);
	dma_free_coherent(NULL, GBE_TLB_SIZE * sizeof(uint16_t),
			  (void *)gbe_tiles.cpu, gbe_tiles.dma);
	release_mem_region(GBE_BASE, sizeof(struct sgi_gbe));
	gbefb_remove_sysfs(&p_dev->dev);
	framebuffer_release(info);

	return 0;
}

static struct platform_driver gbefb_driver = {
	.probe = gbefb_probe,
	.remove = gbefb_remove,
	.driver	= {
		.name = "gbefb",
	},
};

static struct platform_device *gbefb_device;

static int __init gbefb_init(void)
{
	int ret = platform_driver_register(&gbefb_driver);
	if (!ret) {
		gbefb_device = platform_device_alloc("gbefb", 0);
		if (gbefb_device) {
			ret = platform_device_add(gbefb_device);
		} else {
			ret = -ENOMEM;
		}
		if (ret) {
			platform_device_put(gbefb_device);
			platform_driver_unregister(&gbefb_driver);
		}
	}
	return ret;
}

static void __exit gbefb_exit(void)
{
	platform_device_unregister(gbefb_device);
	platform_driver_unregister(&gbefb_driver);
}

module_init(gbefb_init);
module_exit(gbefb_exit);

MODULE_LICENSE("GPL");