summaryrefslogblamecommitdiff
path: root/drivers/gpu/drm/nouveau/nvc0_grhub.fuc
blob: a1a599124cf4960a37cd023be6f88bd744fb9bd4 (plain) (tree)
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







































































































































































































































































































































































































































































































































































































































































































































































































































                                                                             
/* fuc microcode for nvc0 PGRAPH/HUB
 *
 * Copyright 2011 Red Hat Inc.
 *
 * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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: Ben Skeggs
 */

/* To build:
 *    m4 nvc0_grhub.fuc | envyas -a -w -m fuc -V nva3 -o nvc0_grhub.fuc.h
 */

.section nvc0_grhub_data
include(`nvc0_graph.fuc')
gpc_count:		.b32 0
rop_count:		.b32 0
cmd_queue:		queue_init
hub_mmio_list_head:	.b32 0
hub_mmio_list_tail:	.b32 0

ctx_current:		.b32 0

chipsets:
.b8  0xc0 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc0_hub_mmio_tail
.b8  0xc1 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc1_hub_mmio_tail
.b8  0xc3 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc0_hub_mmio_tail
.b8  0xc4 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc0_hub_mmio_tail
.b8  0xc8 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc0_hub_mmio_tail
.b8  0xce 0 0 0
.b16 nvc0_hub_mmio_head
.b16 nvc0_hub_mmio_tail
.b8  0 0 0 0

nvc0_hub_mmio_head:
mmctx_data(0x17e91c, 2)
mmctx_data(0x400204, 2)
mmctx_data(0x404004, 11)
mmctx_data(0x404044, 1)
mmctx_data(0x404094, 14)
mmctx_data(0x4040d0, 7)
mmctx_data(0x4040f8, 1)
mmctx_data(0x404130, 3)
mmctx_data(0x404150, 3)
mmctx_data(0x404164, 2)
mmctx_data(0x404174, 3)
mmctx_data(0x404200, 8)
mmctx_data(0x404404, 14)
mmctx_data(0x404460, 4)
mmctx_data(0x404480, 1)
mmctx_data(0x404498, 1)
mmctx_data(0x404604, 4)
mmctx_data(0x404618, 32)
mmctx_data(0x404698, 21)
mmctx_data(0x4046f0, 2)
mmctx_data(0x404700, 22)
mmctx_data(0x405800, 1)
mmctx_data(0x405830, 3)
mmctx_data(0x405854, 1)
mmctx_data(0x405870, 4)
mmctx_data(0x405a00, 2)
mmctx_data(0x405a18, 1)
mmctx_data(0x406020, 1)
mmctx_data(0x406028, 4)
mmctx_data(0x4064a8, 2)
mmctx_data(0x4064b4, 2)
mmctx_data(0x407804, 1)
mmctx_data(0x40780c, 6)
mmctx_data(0x4078bc, 1)
mmctx_data(0x408000, 7)
mmctx_data(0x408064, 1)
mmctx_data(0x408800, 3)
mmctx_data(0x408900, 4)
mmctx_data(0x408980, 1)
nvc0_hub_mmio_tail:
mmctx_data(0x4064c0, 2)
nvc1_hub_mmio_tail:

.align 256
chan_data:
chan_mmio_count:	.b32 0
chan_mmio_address:	.b32 0

.align 256
xfer_data: 		.b32 0

.section nvc0_grhub_code
bra init
define(`include_code')
include(`nvc0_graph.fuc')

// reports an exception to the host
//
// In: $r15 error code (see nvc0_graph.fuc)
//
error:
	push $r14
	mov $r14 0x814
	shl b32 $r14 6
	iowr I[$r14 + 0x000] $r15	// CC_SCRATCH[5] = error code
	mov $r14 0xc1c
	shl b32 $r14 6
	mov $r15 1
	iowr I[$r14 + 0x000] $r15	// INTR_UP_SET
	pop $r14
	ret

// HUB fuc initialisation, executed by triggering ucode start, will
// fall through to main loop after completion.
//
// Input:
//   CC_SCRATCH[0]: chipset (PMC_BOOT_0 read returns 0x0bad0bad... sigh)
//
// Output:
//   CC_SCRATCH[0]:
//	     31:31: set to signal completion
//   CC_SCRATCH[1]:
//	      31:0: total PGRAPH context size
//
init:
	clear b32 $r0
	mov $sp $r0
	mov $xdbase $r0

	// enable fifo access
	mov $r1 0x1200
	mov $r2 2
	iowr I[$r1 + 0x000] $r2	// FIFO_ENABLE

	// setup i0 handler, and route all interrupts to it
	mov $r1 ih
	mov $iv0 $r1
	mov $r1 0x400
	iowr I[$r1 + 0x300] $r0	// INTR_DISPATCH

	// route HUB_CHANNEL_SWITCH to fuc interrupt 8
	mov $r3 0x404
	shl b32 $r3 6
	mov $r2 0x2003		// { HUB_CHANNEL_SWITCH, ZERO } -> intr 8
	iowr I[$r3 + 0x000] $r2

	// not sure what these are, route them because NVIDIA does, and
	// the IRQ handler will signal the host if we ever get one.. we
	// may find out if/why we need to handle these if so..
	//
	mov $r2 0x2004
	iowr I[$r3 + 0x004] $r2 // { 0x04, ZERO } -> intr 9
	mov $r2 0x200b
	iowr I[$r3 + 0x008] $r2 // { 0x0b, ZERO } -> intr 10
	mov $r2 0x200c
	iowr I[$r3 + 0x01c] $r2 // { 0x0c, ZERO } -> intr 15

	// enable all INTR_UP interrupts
	mov $r2 0xc24
	shl b32 $r2 6
	not b32 $r3 $r0
	iowr I[$r2] $r3

	// enable fifo, ctxsw, 9, 10, 15 interrupts
	mov $r2 -0x78fc		// 0x8704
	sethi $r2 0
	iowr I[$r1 + 0x000] $r2	// INTR_EN_SET

	// fifo level triggered, rest edge
	sub b32 $r1 0x100
	mov $r2 4
	iowr I[$r1] $r2

	// enable interrupts
	bset $flags ie0

	// fetch enabled GPC/ROP counts
	mov $r14 -0x69fc	// 0x409604
	sethi $r14 0x400000
	call nv_rd32
	extr $r1 $r15 16:20
	st b32 D[$r0 + rop_count] $r1
	and $r15 0x1f
	st b32 D[$r0 + gpc_count] $r15

	// set BAR_REQMASK to GPC mask
	mov $r1 1
	shl b32 $r1 $r15
	sub b32 $r1 1
	mov $r2 0x40c
	shl b32 $r2 6
	iowr I[$r2 + 0x000] $r1
	iowr I[$r2 + 0x100] $r1

	// find context data for this chipset
	mov $r2 0x800
	shl b32 $r2 6
	iord $r2 I[$r2 + 0x000]		// CC_SCRATCH[0]
	mov $r15 chipsets - 8
	init_find_chipset:
		add b32 $r15 8
		ld b32 $r3 D[$r15 + 0x00]
		cmpu b32 $r3 $r2
		bra e init_context
		cmpu b32 $r3 0
		bra ne init_find_chipset
		// unknown chipset
		ret

	// context size calculation, reserve first 256 bytes for use by fuc
	init_context:
	mov $r1 256

	// calculate size of mmio context data
	ld b16 $r14 D[$r15 + 4]
	ld b16 $r15 D[$r15 + 6]
	sethi $r14 0
	st b32 D[$r0 + hub_mmio_list_head] $r14
	st b32 D[$r0 + hub_mmio_list_tail] $r15
	call mmctx_size

	// set mmctx base addresses now so we don't have to do it later,
	// they don't (currently) ever change
	mov $r3 0x700
	shl b32 $r3 6
	shr b32 $r4 $r1 8
	iowr I[$r3 + 0x000] $r4		// MMCTX_SAVE_SWBASE
	iowr I[$r3 + 0x100] $r4		// MMCTX_LOAD_SWBASE
	add b32 $r3 0x1300
	add b32 $r1 $r15
	shr b32 $r15 2
	iowr I[$r3 + 0x000] $r15	// MMCTX_LOAD_COUNT, wtf for?!?

	// strands, base offset needs to be aligned to 256 bytes
	shr b32 $r1 8
	add b32 $r1 1
	shl b32 $r1 8
	mov b32 $r15 $r1
	call strand_ctx_init
	add b32 $r1 $r15

	// initialise each GPC in sequence by passing in the offset of its
	// context data in GPCn_CC_SCRATCH[1], and starting its FUC (which
	// has previously been uploaded by the host) running.
	//
	// the GPC fuc init sequence will set GPCn_CC_SCRATCH[0] bit 31
	// when it has completed, and return the size of its context data
	// in GPCn_CC_SCRATCH[1]
	//
	ld b32 $r3 D[$r0 + gpc_count]
	mov $r4 0x2000
	sethi $r4 0x500000
	init_gpc:
		// setup, and start GPC ucode running
		add b32 $r14 $r4 0x804
		mov b32 $r15 $r1
		call nv_wr32			// CC_SCRATCH[1] = ctx offset
		add b32 $r14 $r4 0x800
		mov b32 $r15 $r2
		call nv_wr32			// CC_SCRATCH[0] = chipset
		add b32 $r14 $r4 0x10c
		clear b32 $r15
		call nv_wr32
		add b32 $r14 $r4 0x104
		call nv_wr32			// ENTRY
		add b32 $r14 $r4 0x100
		mov $r15 2			// CTRL_START_TRIGGER
		call nv_wr32			// CTRL

		// wait for it to complete, and adjust context size
		add b32 $r14 $r4 0x800
		init_gpc_wait:
			call nv_rd32
			xbit $r15 $r15 31
			bra e init_gpc_wait
		add b32 $r14 $r4 0x804
		call nv_rd32
		add b32 $r1 $r15

		// next!
		add b32 $r4 0x8000
		sub b32 $r3 1
		bra ne init_gpc

	// save context size, and tell host we're ready
	mov $r2 0x800
	shl b32 $r2 6
	iowr I[$r2 + 0x100] $r1		// CC_SCRATCH[1]  = context size
	add b32 $r2 0x800
	clear b32 $r1
	bset $r1 31
	iowr I[$r2 + 0x000] $r1		// CC_SCRATCH[0] |= 0x80000000

// Main program loop, very simple, sleeps until woken up by the interrupt
// handler, pulls a command from the queue and executes its handler
//
main:
	// sleep until we have something to do
	bset $flags $p0
	sleep $p0
	mov $r13 cmd_queue
	call queue_get
	bra $p1 main

	// context switch, requested by GPU?
	cmpu b32 $r14 0x4001
	bra ne main_not_ctx_switch
		trace_set(T_AUTO)
		mov $r1 0xb00
		shl b32 $r1 6
		iord $r2 I[$r1 + 0x100]		// CHAN_NEXT
		iord $r1 I[$r1 + 0x000]		// CHAN_CUR

		xbit $r3 $r1 31
		bra e chsw_no_prev
			xbit $r3 $r2 31
			bra e chsw_prev_no_next
				push $r2
				mov b32 $r2 $r1
				trace_set(T_SAVE)
				bclr $flags $p1
				bset $flags $p2
				call ctx_xfer
				trace_clr(T_SAVE);
				pop $r2
				trace_set(T_LOAD);
				bset $flags $p1
				call ctx_xfer
				trace_clr(T_LOAD);
				bra chsw_done
			chsw_prev_no_next:
				push $r2
				mov b32 $r2 $r1
				bclr $flags $p1
				bclr $flags $p2
				call ctx_xfer
				pop $r2
				mov $r1 0xb00
				shl b32 $r1 6
				iowr I[$r1] $r2
				bra chsw_done
		chsw_no_prev:
			xbit $r3 $r2 31
			bra e chsw_done
				bset $flags $p1
				bclr $flags $p2
				call ctx_xfer

		// ack the context switch request
		chsw_done:
		mov $r1 0xb0c
		shl b32 $r1 6
		mov $r2 1
		iowr I[$r1 + 0x000] $r2		// 0x409b0c
		trace_clr(T_AUTO)
		bra main

	// request to set current channel? (*not* a context switch)
	main_not_ctx_switch:
	cmpu b32 $r14 0x0001
	bra ne main_not_ctx_chan
		mov b32 $r2 $r15
		call ctx_chan
		bra main_done

	// request to store current channel context?
	main_not_ctx_chan:
	cmpu b32 $r14 0x0002
	bra ne main_not_ctx_save
		trace_set(T_SAVE)
		bclr $flags $p1
		bclr $flags $p2
		call ctx_xfer
		trace_clr(T_SAVE)
		bra main_done

	main_not_ctx_save:
		shl b32 $r15 $r14 16
		or $r15 E_BAD_COMMAND
		call error
		bra main

	main_done:
	mov $r1 0x820
	shl b32 $r1 6
	clear b32 $r2
	bset $r2 31
	iowr I[$r1 + 0x000] $r2		// CC_SCRATCH[0] |= 0x80000000
	bra main

// interrupt handler
ih:
	push $r8
	mov $r8 $flags
	push $r8
	push $r9
	push $r10
	push $r11
	push $r13
	push $r14
	push $r15

	// incoming fifo command?
	iord $r10 I[$r0 + 0x200]	// INTR
	and $r11 $r10 0x00000004
	bra e ih_no_fifo
		// queue incoming fifo command for later processing
		mov $r11 0x1900
		mov $r13 cmd_queue
		iord $r14 I[$r11 + 0x100]	// FIFO_CMD
		iord $r15 I[$r11 + 0x000]	// FIFO_DATA
		call queue_put
		add b32 $r11 0x400
		mov $r14 1
		iowr I[$r11 + 0x000] $r14	// FIFO_ACK

	// context switch request?
	ih_no_fifo:
	and $r11 $r10 0x00000100
	bra e ih_no_ctxsw
		// enqueue a context switch for later processing
		mov $r13 cmd_queue
		mov $r14 0x4001
		call queue_put

	// anything we didn't handle, bring it to the host's attention
	ih_no_ctxsw:
	mov $r11 0x104
	not b32 $r11
	and $r11 $r10 $r11
	bra e ih_no_other
		mov $r10 0xc1c
		shl b32 $r10 6
		iowr I[$r10] $r11	// INTR_UP_SET

	// ack, and wake up main()
	ih_no_other:
	iowr I[$r0 + 0x100] $r10	// INTR_ACK

	pop $r15
	pop $r14
	pop $r13
	pop $r11
	pop $r10
	pop $r9
	pop $r8
	mov $flags $r8
	pop $r8
	bclr $flags $p0
	iret

// Not real sure, but, MEM_CMD 7 will hang forever if this isn't done
ctx_4160s:
	mov $r14 0x4160
	sethi $r14 0x400000
	mov $r15 1
	call nv_wr32
	ctx_4160s_wait:
		call nv_rd32
		xbit $r15 $r15 4
		bra e ctx_4160s_wait
	ret

// Without clearing again at end of xfer, some things cause PGRAPH
// to hang with STATUS=0x00000007 until it's cleared.. fbcon can
// still function with it set however...
ctx_4160c:
	mov $r14 0x4160
	sethi $r14 0x400000
	clear b32 $r15
	call nv_wr32
	ret

// Again, not real sure
//
// In: $r15 value to set 0x404170 to
//
ctx_4170s:
	mov $r14 0x4170
	sethi $r14 0x400000
	or $r15 0x10
	call nv_wr32
	ret

// Waits for a ctx_4170s() call to complete
//
ctx_4170w:
	mov $r14 0x4170
	sethi $r14 0x400000
	call nv_rd32
	and $r15 0x10
	bra ne ctx_4170w
	ret

// Disables various things, waits a bit, and re-enables them..
//
// Not sure how exactly this helps, perhaps "ENABLE" is not such a
// good description for the bits we turn off?  Anyways, without this,
// funny things happen.
//
ctx_redswitch:
	mov $r14 0x614
	shl b32 $r14 6
	mov $r15 0x270
	iowr I[$r14] $r15	// HUB_RED_SWITCH = ENABLE_GPC, POWER_ALL
	mov $r15 8
	ctx_redswitch_delay:
		sub b32 $r15 1
		bra ne ctx_redswitch_delay
	mov $r15 0x770
	iowr I[$r14] $r15	// HUB_RED_SWITCH = ENABLE_ALL, POWER_ALL
	ret

// Not a clue what this is for, except that unless the value is 0x10, the
// strand context is saved (and presumably restored) incorrectly..
//
// In: $r15 value to set to (0x00/0x10 are used)
//
ctx_86c:
	mov $r14 0x86c
	shl b32 $r14 6
	iowr I[$r14] $r15	// HUB(0x86c) = val
	mov $r14 -0x75ec
	sethi $r14 0x400000
	call nv_wr32		// ROP(0xa14) = val
	mov $r14 -0x5794
	sethi $r14 0x410000
	call nv_wr32		// GPC(0x86c) = val
	ret

// ctx_load - load's a channel's ctxctl data, and selects its vm
//
// In: $r2 channel address
//
ctx_load:
	trace_set(T_CHAN)

	// switch to channel, somewhat magic in parts..
	mov $r10 12		// DONE_UNK12
	call wait_donez
	mov $r1 0xa24
	shl b32 $r1 6
	iowr I[$r1 + 0x000] $r0	// 0x409a24
	mov $r3 0xb00
	shl b32 $r3 6
	iowr I[$r3 + 0x100] $r2	// CHAN_NEXT
	mov $r1 0xa0c
	shl b32 $r1 6
	mov $r4 7
	iowr I[$r1 + 0x000] $r2 // MEM_CHAN
	iowr I[$r1 + 0x100] $r4	// MEM_CMD
	ctx_chan_wait_0:
		iord $r4 I[$r1 + 0x100]
		and $r4 0x1f
		bra ne ctx_chan_wait_0
	iowr I[$r3 + 0x000] $r2	// CHAN_CUR

	// load channel header, fetch PGRAPH context pointer
	mov $xtargets $r0
	bclr $r2 31
	shl b32 $r2 4
	add b32 $r2 2

	trace_set(T_LCHAN)
	mov $r1 0xa04
	shl b32 $r1 6
	iowr I[$r1 + 0x000] $r2		// MEM_BASE
	mov $r1 0xa20
	shl b32 $r1 6
	mov $r2 0x0002
	sethi $r2 0x80000000
	iowr I[$r1 + 0x000] $r2		// MEM_TARGET = vram
	mov $r1 0x10			// chan + 0x0210
	mov $r2 xfer_data
	sethi $r2 0x00020000		// 16 bytes
	xdld $r1 $r2
	xdwait
	trace_clr(T_LCHAN)

	// update current context
	ld b32 $r1 D[$r0 + xfer_data + 4]
	shl b32 $r1 24
	ld b32 $r2 D[$r0 + xfer_data + 0]
	shr b32 $r2 8
	or $r1 $r2
	st b32 D[$r0 + ctx_current] $r1

	// set transfer base to start of context, and fetch context header
	trace_set(T_LCTXH)
	mov $r2 0xa04
	shl b32 $r2 6
	iowr I[$r2 + 0x000] $r1		// MEM_BASE
	mov $r2 1
	mov $r1 0xa20
	shl b32 $r1 6
	iowr I[$r1 + 0x000] $r2		// MEM_TARGET = vm
	mov $r1 chan_data
	sethi $r1 0x00060000		// 256 bytes
	xdld $r0 $r1
	xdwait
	trace_clr(T_LCTXH)

	trace_clr(T_CHAN)
	ret

// ctx_chan - handler for HUB_SET_CHAN command, will set a channel as
//            the active channel for ctxctl, but not actually transfer
//            any context data.  intended for use only during initial
//            context construction.
//
// In: $r2 channel address
//
ctx_chan:
	call ctx_4160s
	call ctx_load
	mov $r10 12			// DONE_UNK12
	call wait_donez
	mov $r1 0xa10
	shl b32 $r1 6
	mov $r2 5
	iowr I[$r1 + 0x000] $r2		// MEM_CMD = 5 (???)
	ctx_chan_wait:
		iord $r2 I[$r1 + 0x000]
		or $r2 $r2
		bra ne ctx_chan_wait
	call ctx_4160c
	ret

// Execute per-context state overrides list
//
// Only executed on the first load of a channel.  Might want to look into
// removing this and having the host directly modify the channel's context
// to change this state...  The nouveau DRM already builds this list as
// it's definitely needed for NVIDIA's, so we may as well use it for now
//
// Input: $r1 mmio list length
//
ctx_mmio_exec:
	// set transfer base to be the mmio list
	ld b32 $r3 D[$r0 + chan_mmio_address]
	mov $r2 0xa04
	shl b32 $r2 6
	iowr I[$r2 + 0x000] $r3		// MEM_BASE

	clear b32 $r3
	ctx_mmio_loop:
		// fetch next 256 bytes of mmio list if necessary
		and $r4 $r3 0xff
		bra ne ctx_mmio_pull
			mov $r5 xfer_data
			sethi $r5 0x00060000	// 256 bytes
			xdld $r3 $r5
			xdwait

		// execute a single list entry
		ctx_mmio_pull:
		ld b32 $r14 D[$r4 + xfer_data + 0x00]
		ld b32 $r15 D[$r4 + xfer_data + 0x04]
		call nv_wr32

		// next!
		add b32 $r3 8
		sub b32 $r1 1
		bra ne ctx_mmio_loop

	// set transfer base back to the current context
	ctx_mmio_done:
	ld b32 $r3 D[$r0 + ctx_current]
	iowr I[$r2 + 0x000] $r3		// MEM_BASE

	// disable the mmio list now, we don't need/want to execute it again
	st b32 D[$r0 + chan_mmio_count] $r0
	mov $r1 chan_data
	sethi $r1 0x00060000		// 256 bytes
	xdst $r0 $r1
	xdwait
	ret

// Transfer HUB context data between GPU and storage area
//
// In: $r2 channel address
//     $p1 clear on save, set on load
//     $p2 set if opposite direction done/will be done, so:
//		on save it means: "a load will follow this save"
//		on load it means: "a save preceeded this load"
//
ctx_xfer:
	bra not $p1 ctx_xfer_pre
	bra $p2 ctx_xfer_pre_load
	ctx_xfer_pre:
		mov $r15 0x10
		call ctx_86c
		call ctx_4160s
		bra not $p1 ctx_xfer_exec

	ctx_xfer_pre_load:
		mov $r15 2
		call ctx_4170s
		call ctx_4170w
		call ctx_redswitch
		clear b32 $r15
		call ctx_4170s
		call ctx_load

	// fetch context pointer, and initiate xfer on all GPCs
	ctx_xfer_exec:
	ld b32 $r1 D[$r0 + ctx_current]
	mov $r2 0x414
	shl b32 $r2 6
	iowr I[$r2 + 0x000] $r0	// BAR_STATUS = reset
	mov $r14 -0x5b00
	sethi $r14 0x410000
	mov b32 $r15 $r1
	call nv_wr32		// GPC_BCAST_WRCMD_DATA = ctx pointer
	add b32 $r14 4
	xbit $r15 $flags $p1
	xbit $r2 $flags $p2
	shl b32 $r2 1
	or $r15 $r2
	call nv_wr32		// GPC_BCAST_WRCMD_CMD = GPC_XFER(type)

	// strands
	mov $r1 0x4afc
	sethi $r1 0x20000
	mov $r2 0xc
	iowr I[$r1] $r2		// STRAND_CMD(0x3f) = 0x0c
	call strand_wait
	mov $r2 0x47fc
	sethi $r2 0x20000
	iowr I[$r2] $r0		// STRAND_FIRST_GENE(0x3f) = 0x00
	xbit $r2 $flags $p1
	add b32 $r2 3
	iowr I[$r1] $r2		// STRAND_CMD(0x3f) = 0x03/0x04 (SAVE/LOAD)

	// mmio context
	xbit $r10 $flags $p1	// direction
	or $r10 6		// first, last
	mov $r11 0		// base = 0
	ld b32 $r12 D[$r0 + hub_mmio_list_head]
	ld b32 $r13 D[$r0 + hub_mmio_list_tail]
	mov $r14 0		// not multi
	call mmctx_xfer

	// wait for GPCs to all complete
	mov $r10 8		// DONE_BAR
	call wait_doneo

	// wait for strand xfer to complete
	call strand_wait

	// post-op
	bra $p1 ctx_xfer_post
		mov $r10 12		// DONE_UNK12
		call wait_donez
		mov $r1 0xa10
		shl b32 $r1 6
		mov $r2 5
		iowr I[$r1] $r2		// MEM_CMD
		ctx_xfer_post_save_wait:
			iord $r2 I[$r1]
			or $r2 $r2
			bra ne ctx_xfer_post_save_wait

	bra $p2 ctx_xfer_done
	ctx_xfer_post:
		mov $r15 2
		call ctx_4170s
		clear b32 $r15
		call ctx_86c
		call strand_post
		call ctx_4170w
		clear b32 $r15
		call ctx_4170s

		bra not $p1 ctx_xfer_no_post_mmio
		ld b32 $r1 D[$r0 + chan_mmio_count]
		or $r1 $r1
		bra e ctx_xfer_no_post_mmio
			call ctx_mmio_exec

		ctx_xfer_no_post_mmio:
		call ctx_4160c

	ctx_xfer_done:
	ret

.align 256