aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/powermac/smp.c
blob: 686ed82bde79a6608abcf5915848a47a6ff8ffc8 (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
/*
 * SMP support for power macintosh.
 *
 * We support both the old "powersurge" SMP architecture
 * and the current Core99 (G4 PowerMac) machines.
 *
 * Note that we don't support the very first rev. of
 * Apple/DayStar 2 CPUs board, the one with the funky
 * watchdog. Hopefully, none of these should be there except
 * maybe internally to Apple. I should probably still add some
 * code to detect this card though and disable SMP. --BenH.
 *
 * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
 * and Ben Herrenschmidt <benh@kernel.crashing.org>.
 *
 * Support for DayStar quad CPU cards
 * Copyright (C) XLR8, Inc. 1994-2000
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 */
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/hardirq.h>
#include <linux/cpu.h>
#include <linux/compiler.h>

#include <asm/ptrace.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/time.h>
#include <asm/mpic.h>
#include <asm/cacheflush.h>
#include <asm/keylargo.h>
#include <asm/pmac_low_i2c.h>
#include <asm/pmac_pfunc.h>

#define DEBUG

#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif

extern void __secondary_start_pmac_0(void);
extern int pmac_pfunc_base_install(void);

#ifdef CONFIG_PPC32

/* Sync flag for HW tb sync */
static volatile int sec_tb_reset = 0;

/*
 * Powersurge (old powermac SMP) support.
 */

/* Addresses for powersurge registers */
#define HAMMERHEAD_BASE		0xf8000000
#define HHEAD_CONFIG		0x90
#define HHEAD_SEC_INTR		0xc0

/* register for interrupting the primary processor on the powersurge */
/* N.B. this is actually the ethernet ROM! */
#define PSURGE_PRI_INTR		0xf3019000

/* register for storing the start address for the secondary processor */
/* N.B. this is the PCI config space address register for the 1st bridge */
#define PSURGE_START		0xf2800000

/* Daystar/XLR8 4-CPU card */
#define PSURGE_QUAD_REG_ADDR	0xf8800000

#define PSURGE_QUAD_IRQ_SET	0
#define PSURGE_QUAD_IRQ_CLR	1
#define PSURGE_QUAD_IRQ_PRIMARY	2
#define PSURGE_QUAD_CKSTOP_CTL	3
#define PSURGE_QUAD_PRIMARY_ARB	4
#define PSURGE_QUAD_BOARD_ID	6
#define PSURGE_QUAD_WHICH_CPU	7
#define PSURGE_QUAD_CKSTOP_RDBK	8
#define PSURGE_QUAD_RESET_CTL	11

#define PSURGE_QUAD_OUT(r, v)	(out_8(quad_base + ((r) << 4) + 4, (v)))
#define PSURGE_QUAD_IN(r)	(in_8(quad_base + ((r) << 4) + 4) & 0x0f)
#define PSURGE_QUAD_BIS(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
#define PSURGE_QUAD_BIC(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))

/* virtual addresses for the above */
static volatile u8 __iomem *hhead_base;
static volatile u8 __iomem *quad_base;
static volatile u32 __iomem *psurge_pri_intr;
static volatile u8 __iomem *psurge_sec_intr;
static volatile u32 __iomem *psurge_start;

/* values for psurge_type */
#define PSURGE_NONE		-1
#define PSURGE_DUAL		0
#define PSURGE_QUAD_OKEE	1
#define PSURGE_QUAD_COTTON	2
#define PSURGE_QUAD_ICEGRASS	3

/* what sort of powersurge board we have */
static int psurge_type = PSURGE_NONE;

/*
 * Set and clear IPIs for powersurge.
 */
static inline void psurge_set_ipi(int cpu)
{
	if (psurge_type == PSURGE_NONE)
		return;
	if (cpu == 0)
		in_be32(psurge_pri_intr);
	else if (psurge_type == PSURGE_DUAL)
		out_8(psurge_sec_intr, 0);
	else
		PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
}

static inline void psurge_clr_ipi(int cpu)
{
	if (cpu > 0) {
		switch(psurge_type) {
		case PSURGE_DUAL:
			out_8(psurge_sec_intr, ~0);
		case PSURGE_NONE:
			break;
		default:
			PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
		}
	}
}

/*
 * On powersurge (old SMP powermac architecture) we don't have
 * separate IPIs for separate messages like openpic does.  Instead
 * we have a bitmap for each processor, where a 1 bit means that
 * the corresponding message is pending for that processor.
 * Ideally each cpu's entry would be in a different cache line.
 *  -- paulus.
 */
static unsigned long psurge_smp_message[NR_CPUS];

void psurge_smp_message_recv(void)
{
	int cpu = smp_processor_id();
	int msg;

	/* clear interrupt */
	psurge_clr_ipi(cpu);

	if (num_online_cpus() < 2)
		return;

	/* make sure there is a message there */
	for (msg = 0; msg < 4; msg++)
		if (test_and_clear_bit(msg, &psurge_smp_message[cpu]))
			smp_message_recv(msg);
}

irqreturn_t psurge_primary_intr(int irq, void *d)
{
	psurge_smp_message_recv();
	return IRQ_HANDLED;
}

static void smp_psurge_message_pass(int target, int msg)
{
	int i;

	if (num_online_cpus() < 2)
		return;

	for_each_online_cpu(i) {
		if (target == MSG_ALL
		    || (target == MSG_ALL_BUT_SELF && i != smp_processor_id())
		    || target == i) {
			set_bit(msg, &psurge_smp_message[i]);
			psurge_set_ipi(i);
		}
	}
}

/*
 * Determine a quad card presence. We read the board ID register, we
 * force the data bus to change to something else, and we read it again.
 * It it's stable, then the register probably exist (ugh !)
 */
static int __init psurge_quad_probe(void)
{
	int type;
	unsigned int i;

	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
		return PSURGE_DUAL;

	/* looks OK, try a slightly more rigorous test */
	/* bogus is not necessarily cacheline-aligned,
	   though I don't suppose that really matters.  -- paulus */
	for (i = 0; i < 100; i++) {
		volatile u32 bogus[8];
		bogus[(0+i)%8] = 0x00000000;
		bogus[(1+i)%8] = 0x55555555;
		bogus[(2+i)%8] = 0xFFFFFFFF;
		bogus[(3+i)%8] = 0xAAAAAAAA;
		bogus[(4+i)%8] = 0x33333333;
		bogus[(5+i)%8] = 0xCCCCCCCC;
		bogus[(6+i)%8] = 0xCCCCCCCC;
		bogus[(7+i)%8] = 0x33333333;
		wmb();
		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
		mb();
		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
			return PSURGE_DUAL;
	}
	return type;
}

static void __init psurge_quad_init(void)
{
	int procbits;

	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
	if (psurge_type == PSURGE_QUAD_ICEGRASS)
		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
	else
		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
	mdelay(33);
	out_8(psurge_sec_intr, ~0);
	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
	if (psurge_type != PSURGE_QUAD_ICEGRASS)
		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
	mdelay(33);
	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
	mdelay(33);
	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
	mdelay(33);
}

static int __init smp_psurge_probe(void)
{
	int i, ncpus;
	struct device_node *dn;

	/* We don't do SMP on the PPC601 -- paulus */
	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
		return 1;

	/*
	 * The powersurge cpu board can be used in the generation
	 * of powermacs that have a socket for an upgradeable cpu card,
	 * including the 7500, 8500, 9500, 9600.
	 * The device tree doesn't tell you if you have 2 cpus because
	 * OF doesn't know anything about the 2nd processor.
	 * Instead we look for magic bits in magic registers,
	 * in the hammerhead memory controller in the case of the
	 * dual-cpu powersurge board.  -- paulus.
	 */
	dn = of_find_node_by_name(NULL, "hammerhead");
	if (dn == NULL)
		return 1;
	of_node_put(dn);

	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;

	psurge_type = psurge_quad_probe();
	if (psurge_type != PSURGE_DUAL) {
		psurge_quad_init();
		/* All released cards using this HW design have 4 CPUs */
		ncpus = 4;
	} else {
		iounmap(quad_base);
		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
			/* not a dual-cpu card */
			iounmap(hhead_base);
			psurge_type = PSURGE_NONE;
			return 1;
		}
		ncpus = 2;
	}

	psurge_start = ioremap(PSURGE_START, 4);
	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);

	/*
	 * This is necessary because OF doesn't know about the
	 * secondary cpu(s), and thus there aren't nodes in the
	 * device tree for them, and smp_setup_cpu_maps hasn't
	 * set their bits in cpu_possible_map and cpu_present_map.
	 */
	if (ncpus > NR_CPUS)
		ncpus = NR_CPUS;
	for (i = 1; i < ncpus ; ++i) {
		cpu_set(i, cpu_present_map);
		cpu_set(i, cpu_possible_map);
		set_hard_smp_processor_id(i, i);
	}

	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);

	return ncpus;
}

static void __init smp_psurge_kick_cpu(int nr)
{
	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
	unsigned long a;
	int i;

	/* may need to flush here if secondary bats aren't setup */
	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
	asm volatile("sync");

	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);

	out_be32(psurge_start, start);
	mb();

	psurge_set_ipi(nr);
	/*
	 * We can't use udelay here because the timebase is now frozen.
	 */
	for (i = 0; i < 2000; ++i)
		barrier();
	psurge_clr_ipi(nr);

	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
}

/*
 * With the dual-cpu powersurge board, the decrementers and timebases
 * of both cpus are frozen after the secondary cpu is started up,
 * until we give the secondary cpu another interrupt.  This routine
 * uses this to get the timebases synchronized.
 *  -- paulus.
 */
static void __init psurge_dual_sync_tb(int cpu_nr)
{
	int t;

	set_dec(tb_ticks_per_jiffy);
	/* XXX fixme */
	set_tb(0, 0);

	if (cpu_nr > 0) {
		mb();
		sec_tb_reset = 1;
		return;
	}

	/* wait for the secondary to have reset its TB before proceeding */
	for (t = 10000000; t > 0 && !sec_tb_reset; --t)
		;

	/* now interrupt the secondary, starting both TBs */
	psurge_set_ipi(1);
}

static struct irqaction psurge_irqaction = {
	.handler = psurge_primary_intr,
	.flags = IRQF_DISABLED,
	.mask = CPU_MASK_NONE,
	.name = "primary IPI",
};

static void __init smp_psurge_setup_cpu(int cpu_nr)
{

	if (cpu_nr == 0) {
		/* If we failed to start the second CPU, we should still
		 * send it an IPI to start the timebase & DEC or we might
		 * have them stuck.
		 */
		if (num_online_cpus() < 2) {
			if (psurge_type == PSURGE_DUAL)
				psurge_set_ipi(1);
			return;
		}
		/* reset the entry point so if we get another intr we won't
		 * try to startup again */
		out_be32(psurge_start, 0x100);
		if (setup_irq(30, &psurge_irqaction))
			printk(KERN_ERR "Couldn't get primary IPI interrupt");
	}

	if (psurge_type == PSURGE_DUAL)
		psurge_dual_sync_tb(cpu_nr);
}

void __init smp_psurge_take_timebase(void)
{
	/* Dummy implementation */
}

void __init smp_psurge_give_timebase(void)
{
	/* Dummy implementation */
}

/* PowerSurge-style Macs */
struct smp_ops_t psurge_smp_ops = {
	.message_pass	= smp_psurge_message_pass,
	.probe		= smp_psurge_probe,
	.kick_cpu	= smp_psurge_kick_cpu,
	.setup_cpu	= smp_psurge_setup_cpu,
	.give_timebase	= smp_psurge_give_timebase,
	.take_timebase	= smp_psurge_take_timebase,
};
#endif /* CONFIG_PPC32 - actually powersurge support */

/*
 * Core 99 and later support
 */

static void (*pmac_tb_freeze)(int freeze);
static u64 timebase;
static int tb_req;

static void smp_core99_give_timebase(void)
{
	unsigned long flags;

	local_irq_save(flags);

	while(!tb_req)
		barrier();
	tb_req = 0;
	(*pmac_tb_freeze)(1);
	mb();
	timebase = get_tb();
	mb();
	while (timebase)
		barrier();
	mb();
	(*pmac_tb_freeze)(0);
	mb();

	local_irq_restore(flags);
}


static void __devinit smp_core99_take_timebase(void)
{
	unsigned long flags;

	local_irq_save(flags);

	tb_req = 1;
	mb();
	while (!timebase)
		barrier();
	mb();
	set_tb(timebase >> 32, timebase & 0xffffffff);
	timebase = 0;
	mb();
	set_dec(tb_ticks_per_jiffy/2);

	local_irq_restore(flags);
}

#ifdef CONFIG_PPC64
/*
 * G5s enable/disable the timebase via an i2c-connected clock chip.
 */
static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
static u8 pmac_tb_pulsar_addr;

static void smp_core99_cypress_tb_freeze(int freeze)
{
	u8 data;
	int rc;

	/* Strangely, the device-tree says address is 0xd2, but darwin
	 * accesses 0xd0 ...
	 */
	pmac_i2c_setmode(pmac_tb_clock_chip_host,
			 pmac_i2c_mode_combined);
	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
			   0xd0 | pmac_i2c_read,
			   1, 0x81, &data, 1);
	if (rc != 0)
		goto bail;

	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);

       	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
			   0xd0 | pmac_i2c_write,
			   1, 0x81, &data, 1);

 bail:
	if (rc != 0) {
		printk("Cypress Timebase %s rc: %d\n",
		       freeze ? "freeze" : "unfreeze", rc);
		panic("Timebase freeze failed !\n");
	}
}


static void smp_core99_pulsar_tb_freeze(int freeze)
{
	u8 data;
	int rc;

	pmac_i2c_setmode(pmac_tb_clock_chip_host,
			 pmac_i2c_mode_combined);
	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
			   pmac_tb_pulsar_addr | pmac_i2c_read,
			   1, 0x2e, &data, 1);
	if (rc != 0)
		goto bail;

	data = (data & 0x88) | (freeze ? 0x11 : 0x22);

	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
			   pmac_tb_pulsar_addr | pmac_i2c_write,
			   1, 0x2e, &data, 1);
 bail:
	if (rc != 0) {
		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
		       freeze ? "freeze" : "unfreeze", rc);
		panic("Timebase freeze failed !\n");
	}
}

static void __init smp_core99_setup_i2c_hwsync(int ncpus)
{
	struct device_node *cc = NULL;	
	struct device_node *p;
	const char *name = NULL;
	const u32 *reg;
	int ok;

	/* Look for the clock chip */
	while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
		p = of_get_parent(cc);
		ok = p && of_device_is_compatible(p, "uni-n-i2c");
		of_node_put(p);
		if (!ok)
			continue;

		pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
		if (pmac_tb_clock_chip_host == NULL)
			continue;
		reg = of_get_property(cc, "reg", NULL);
		if (reg == NULL)
			continue;
		switch (*reg) {
		case 0xd2:
			if (of_device_is_compatible(cc,"pulsar-legacy-slewing")) {
				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
				pmac_tb_pulsar_addr = 0xd2;
				name = "Pulsar";
			} else if (of_device_is_compatible(cc, "cy28508")) {
				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
				name = "Cypress";
			}
			break;
		case 0xd4:
			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
			pmac_tb_pulsar_addr = 0xd4;
			name = "Pulsar";
			break;
		}
		if (pmac_tb_freeze != NULL)
			break;
	}
	if (pmac_tb_freeze != NULL) {
		/* Open i2c bus for synchronous access */
		if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
			printk(KERN_ERR "Failed top open i2c bus for clock"
			       " sync, fallback to software sync !\n");
			goto no_i2c_sync;
		}
		printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
		       name);
		return;
	}
 no_i2c_sync:
	pmac_tb_freeze = NULL;
	pmac_tb_clock_chip_host = NULL;
}



/*
 * Newer G5s uses a platform function
 */

static void smp_core99_pfunc_tb_freeze(int freeze)
{
	struct device_node *cpus;
	struct pmf_args args;

	cpus = of_find_node_by_path("/cpus");
	BUG_ON(cpus == NULL);
	args.count = 1;
	args.u[0].v = !freeze;
	pmf_call_function(cpus, "cpu-timebase", &args);
	of_node_put(cpus);
}

#else /* CONFIG_PPC64 */

/*
 * SMP G4 use a GPIO to enable/disable the timebase.
 */

static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */

static void smp_core99_gpio_tb_freeze(int freeze)
{
	if (freeze)
		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
	else
		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
}


#endif /* !CONFIG_PPC64 */

/* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
volatile static long int core99_l2_cache;
volatile static long int core99_l3_cache;

static void __devinit core99_init_caches(int cpu)
{
#ifndef CONFIG_PPC64
	if (!cpu_has_feature(CPU_FTR_L2CR))
		return;

	if (cpu == 0) {
		core99_l2_cache = _get_L2CR();
		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
	} else {
		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
		_set_L2CR(0);
		_set_L2CR(core99_l2_cache);
		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
	}

	if (!cpu_has_feature(CPU_FTR_L3CR))
		return;

	if (cpu == 0){
		core99_l3_cache = _get_L3CR();
		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
	} else {
		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
		_set_L3CR(0);
		_set_L3CR(core99_l3_cache);
		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
	}
#endif /* !CONFIG_PPC64 */
}

static void __init smp_core99_setup(int ncpus)
{
#ifdef CONFIG_PPC64

	/* i2c based HW sync on some G5s */
	if (machine_is_compatible("PowerMac7,2") ||
	    machine_is_compatible("PowerMac7,3") ||
	    machine_is_compatible("RackMac3,1"))
		smp_core99_setup_i2c_hwsync(ncpus);

	/* pfunc based HW sync on recent G5s */
	if (pmac_tb_freeze == NULL) {
		struct device_node *cpus =
			of_find_node_by_path("/cpus");
		if (cpus &&
		    of_get_property(cpus, "platform-cpu-timebase", NULL)) {
			pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
			printk(KERN_INFO "Processor timebase sync using"
			       " platform function\n");
		}
	}

#else /* CONFIG_PPC64 */

	/* GPIO based HW sync on ppc32 Core99 */
	if (pmac_tb_freeze == NULL && !machine_is_compatible("MacRISC4")) {
		struct device_node *cpu;
		const u32 *tbprop = NULL;

		core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
		cpu = of_find_node_by_type(NULL, "cpu");
		if (cpu != NULL) {
			tbprop = of_get_property(cpu, "timebase-enable", NULL);
			if (tbprop)
				core99_tb_gpio = *tbprop;
			of_node_put(cpu);
		}
		pmac_tb_freeze = smp_core99_gpio_tb_freeze;
		printk(KERN_INFO "Processor timebase sync using"
		       " GPIO 0x%02x\n", core99_tb_gpio);
	}

#endif /* CONFIG_PPC64 */

	/* No timebase sync, fallback to software */
	if (pmac_tb_freeze == NULL) {
		smp_ops->give_timebase = smp_generic_give_timebase;
		smp_ops->take_timebase = smp_generic_take_timebase;
		printk(KERN_INFO "Processor timebase sync using software\n");
	}

#ifndef CONFIG_PPC64
	{
		int i;

		/* XXX should get this from reg properties */
		for (i = 1; i < ncpus; ++i)
			smp_hw_index[i] = i;
	}
#endif

	/* 32 bits SMP can't NAP */
	if (!machine_is_compatible("MacRISC4"))
		powersave_nap = 0;
}

static int __init smp_core99_probe(void)
{
	struct device_node *cpus;
	int ncpus = 0;

	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);

	/* Count CPUs in the device-tree */
       	for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
	       	++ncpus;

	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);

	/* Nothing more to do if less than 2 of them */
	if (ncpus <= 1)
		return 1;

	/* We need to perform some early initialisations before we can start
	 * setting up SMP as we are running before initcalls
	 */
	pmac_pfunc_base_install();
	pmac_i2c_init();

	/* Setup various bits like timebase sync method, ability to nap, ... */
	smp_core99_setup(ncpus);

	/* Install IPIs */
	mpic_request_ipis();

	/* Collect l2cr and l3cr values from CPU 0 */
	core99_init_caches(0);

	return ncpus;
}

static void __devinit smp_core99_kick_cpu(int nr)
{
	unsigned int save_vector;
	unsigned long target, flags;
	volatile unsigned int *vector
		 = ((volatile unsigned int *)(KERNELBASE+0x100));

	if (nr < 0 || nr > 3)
		return;

	if (ppc_md.progress)
		ppc_md.progress("smp_core99_kick_cpu", 0x346);

	local_irq_save(flags);

	/* Save reset vector */
	save_vector = *vector;

	/* Setup fake reset vector that does
	 *   b __secondary_start_pmac_0 + nr*8 - KERNELBASE
	 */
	target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
	create_branch((unsigned long)vector, target, BRANCH_SET_LINK);

	/* Put some life in our friend */
	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);

	/* FIXME: We wait a bit for the CPU to take the exception, I should
	 * instead wait for the entry code to set something for me. Well,
	 * ideally, all that crap will be done in prom.c and the CPU left
	 * in a RAM-based wait loop like CHRP.
	 */
	mdelay(1);

	/* Restore our exception vector */
	*vector = save_vector;
	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);

	local_irq_restore(flags);
	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
}

static void __devinit smp_core99_setup_cpu(int cpu_nr)
{
	/* Setup L2/L3 */
	if (cpu_nr != 0)
		core99_init_caches(cpu_nr);

	/* Setup openpic */
	mpic_setup_this_cpu();

	if (cpu_nr == 0) {
#ifdef CONFIG_PPC64
		extern void g5_phy_disable_cpu1(void);

		/* Close i2c bus if it was used for tb sync */
		if (pmac_tb_clock_chip_host) {
			pmac_i2c_close(pmac_tb_clock_chip_host);
			pmac_tb_clock_chip_host	= NULL;
		}

		/* If we didn't start the second CPU, we must take
		 * it off the bus
		 */
		if (machine_is_compatible("MacRISC4") &&
		    num_online_cpus() < 2)		
			g5_phy_disable_cpu1();
#endif /* CONFIG_PPC64 */

		if (ppc_md.progress)
			ppc_md.progress("core99_setup_cpu 0 done", 0x349);
	}
}


#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)

int smp_core99_cpu_disable(void)
{
	cpu_clear(smp_processor_id(), cpu_online_map);

	/* XXX reset cpu affinity here */
	mpic_cpu_set_priority(0xf);
	asm volatile("mtdec %0" : : "r" (0x7fffffff));
	mb();
	udelay(20);
	asm volatile("mtdec %0" : : "r" (0x7fffffff));
	return 0;
}

extern void low_cpu_die(void) __attribute__((noreturn)); /* in sleep.S */
static int cpu_dead[NR_CPUS];

void cpu_die(void)
{
	local_irq_disable();
	cpu_dead[smp_processor_id()] = 1;
	mb();
	low_cpu_die();
}

void smp_core99_cpu_die(unsigned int cpu)
{
	int timeout;

	timeout = 1000;
	while (!cpu_dead[cpu]) {
		if (--timeout == 0) {
			printk("CPU %u refused to die!\n", cpu);
			break;
		}
		msleep(1);
	}
	cpu_dead[cpu] = 0;
}

#endif /* CONFIG_HOTPLUG_CPU && CONFIG_PP32 */

/* Core99 Macs (dual G4s and G5s) */
struct smp_ops_t core99_smp_ops = {
	.message_pass	= smp_mpic_message_pass,
	.probe		= smp_core99_probe,
	.kick_cpu	= smp_core99_kick_cpu,
	.setup_cpu	= smp_core99_setup_cpu,
	.give_timebase	= smp_core99_give_timebase,
	.take_timebase	= smp_core99_take_timebase,
#if defined(CONFIG_HOTPLUG_CPU)
# if defined(CONFIG_PPC32)
	.cpu_disable	= smp_core99_cpu_disable,
	.cpu_die	= smp_core99_cpu_die,
# endif
# if defined(CONFIG_PPC64)
	.cpu_disable	= generic_cpu_disable,
	.cpu_die	= generic_cpu_die,
	/* intentionally do *NOT* assign cpu_enable,
	 * the generic code will use kick_cpu then! */
# endif
#endif
};