xref: /linux/arch/powerpc/platforms/powermac/smp.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
1 /*
2  * SMP support for power macintosh.
3  *
4  * We support both the old "powersurge" SMP architecture
5  * and the current Core99 (G4 PowerMac) machines.
6  *
7  * Note that we don't support the very first rev. of
8  * Apple/DayStar 2 CPUs board, the one with the funky
9  * watchdog. Hopefully, none of these should be there except
10  * maybe internally to Apple. I should probably still add some
11  * code to detect this card though and disable SMP. --BenH.
12  *
13  * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
14  * and Ben Herrenschmidt <benh@kernel.crashing.org>.
15  *
16  * Support for DayStar quad CPU cards
17  * Copyright (C) XLR8, Inc. 1994-2000
18  *
19  *  This program is free software; you can redistribute it and/or
20  *  modify it under the terms of the GNU General Public License
21  *  as published by the Free Software Foundation; either version
22  *  2 of the License, or (at your option) any later version.
23  */
24 #include <linux/config.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/smp.h>
28 #include <linux/smp_lock.h>
29 #include <linux/interrupt.h>
30 #include <linux/kernel_stat.h>
31 #include <linux/delay.h>
32 #include <linux/init.h>
33 #include <linux/spinlock.h>
34 #include <linux/errno.h>
35 #include <linux/hardirq.h>
36 #include <linux/cpu.h>
37 #include <linux/compiler.h>
38 
39 #include <asm/ptrace.h>
40 #include <asm/atomic.h>
41 #include <asm/irq.h>
42 #include <asm/page.h>
43 #include <asm/pgtable.h>
44 #include <asm/sections.h>
45 #include <asm/io.h>
46 #include <asm/prom.h>
47 #include <asm/smp.h>
48 #include <asm/machdep.h>
49 #include <asm/pmac_feature.h>
50 #include <asm/time.h>
51 #include <asm/mpic.h>
52 #include <asm/cacheflush.h>
53 #include <asm/keylargo.h>
54 #include <asm/pmac_low_i2c.h>
55 
56 #undef DEBUG
57 
58 #ifdef DEBUG
59 #define DBG(fmt...) udbg_printf(fmt)
60 #else
61 #define DBG(fmt...)
62 #endif
63 
64 extern void __secondary_start_pmac_0(void);
65 
66 #ifdef CONFIG_PPC32
67 
68 /* Sync flag for HW tb sync */
69 static volatile int sec_tb_reset = 0;
70 
71 /*
72  * Powersurge (old powermac SMP) support.
73  */
74 
75 /* Addresses for powersurge registers */
76 #define HAMMERHEAD_BASE		0xf8000000
77 #define HHEAD_CONFIG		0x90
78 #define HHEAD_SEC_INTR		0xc0
79 
80 /* register for interrupting the primary processor on the powersurge */
81 /* N.B. this is actually the ethernet ROM! */
82 #define PSURGE_PRI_INTR		0xf3019000
83 
84 /* register for storing the start address for the secondary processor */
85 /* N.B. this is the PCI config space address register for the 1st bridge */
86 #define PSURGE_START		0xf2800000
87 
88 /* Daystar/XLR8 4-CPU card */
89 #define PSURGE_QUAD_REG_ADDR	0xf8800000
90 
91 #define PSURGE_QUAD_IRQ_SET	0
92 #define PSURGE_QUAD_IRQ_CLR	1
93 #define PSURGE_QUAD_IRQ_PRIMARY	2
94 #define PSURGE_QUAD_CKSTOP_CTL	3
95 #define PSURGE_QUAD_PRIMARY_ARB	4
96 #define PSURGE_QUAD_BOARD_ID	6
97 #define PSURGE_QUAD_WHICH_CPU	7
98 #define PSURGE_QUAD_CKSTOP_RDBK	8
99 #define PSURGE_QUAD_RESET_CTL	11
100 
101 #define PSURGE_QUAD_OUT(r, v)	(out_8(quad_base + ((r) << 4) + 4, (v)))
102 #define PSURGE_QUAD_IN(r)	(in_8(quad_base + ((r) << 4) + 4) & 0x0f)
103 #define PSURGE_QUAD_BIS(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
104 #define PSURGE_QUAD_BIC(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
105 
106 /* virtual addresses for the above */
107 static volatile u8 __iomem *hhead_base;
108 static volatile u8 __iomem *quad_base;
109 static volatile u32 __iomem *psurge_pri_intr;
110 static volatile u8 __iomem *psurge_sec_intr;
111 static volatile u32 __iomem *psurge_start;
112 
113 /* values for psurge_type */
114 #define PSURGE_NONE		-1
115 #define PSURGE_DUAL		0
116 #define PSURGE_QUAD_OKEE	1
117 #define PSURGE_QUAD_COTTON	2
118 #define PSURGE_QUAD_ICEGRASS	3
119 
120 /* what sort of powersurge board we have */
121 static int psurge_type = PSURGE_NONE;
122 
123 /*
124  * Set and clear IPIs for powersurge.
125  */
126 static inline void psurge_set_ipi(int cpu)
127 {
128 	if (psurge_type == PSURGE_NONE)
129 		return;
130 	if (cpu == 0)
131 		in_be32(psurge_pri_intr);
132 	else if (psurge_type == PSURGE_DUAL)
133 		out_8(psurge_sec_intr, 0);
134 	else
135 		PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
136 }
137 
138 static inline void psurge_clr_ipi(int cpu)
139 {
140 	if (cpu > 0) {
141 		switch(psurge_type) {
142 		case PSURGE_DUAL:
143 			out_8(psurge_sec_intr, ~0);
144 		case PSURGE_NONE:
145 			break;
146 		default:
147 			PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
148 		}
149 	}
150 }
151 
152 /*
153  * On powersurge (old SMP powermac architecture) we don't have
154  * separate IPIs for separate messages like openpic does.  Instead
155  * we have a bitmap for each processor, where a 1 bit means that
156  * the corresponding message is pending for that processor.
157  * Ideally each cpu's entry would be in a different cache line.
158  *  -- paulus.
159  */
160 static unsigned long psurge_smp_message[NR_CPUS];
161 
162 void psurge_smp_message_recv(struct pt_regs *regs)
163 {
164 	int cpu = smp_processor_id();
165 	int msg;
166 
167 	/* clear interrupt */
168 	psurge_clr_ipi(cpu);
169 
170 	if (num_online_cpus() < 2)
171 		return;
172 
173 	/* make sure there is a message there */
174 	for (msg = 0; msg < 4; msg++)
175 		if (test_and_clear_bit(msg, &psurge_smp_message[cpu]))
176 			smp_message_recv(msg, regs);
177 }
178 
179 irqreturn_t psurge_primary_intr(int irq, void *d, struct pt_regs *regs)
180 {
181 	psurge_smp_message_recv(regs);
182 	return IRQ_HANDLED;
183 }
184 
185 static void smp_psurge_message_pass(int target, int msg)
186 {
187 	int i;
188 
189 	if (num_online_cpus() < 2)
190 		return;
191 
192 	for (i = 0; i < NR_CPUS; i++) {
193 		if (!cpu_online(i))
194 			continue;
195 		if (target == MSG_ALL
196 		    || (target == MSG_ALL_BUT_SELF && i != smp_processor_id())
197 		    || target == i) {
198 			set_bit(msg, &psurge_smp_message[i]);
199 			psurge_set_ipi(i);
200 		}
201 	}
202 }
203 
204 /*
205  * Determine a quad card presence. We read the board ID register, we
206  * force the data bus to change to something else, and we read it again.
207  * It it's stable, then the register probably exist (ugh !)
208  */
209 static int __init psurge_quad_probe(void)
210 {
211 	int type;
212 	unsigned int i;
213 
214 	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
215 	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
216 	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
217 		return PSURGE_DUAL;
218 
219 	/* looks OK, try a slightly more rigorous test */
220 	/* bogus is not necessarily cacheline-aligned,
221 	   though I don't suppose that really matters.  -- paulus */
222 	for (i = 0; i < 100; i++) {
223 		volatile u32 bogus[8];
224 		bogus[(0+i)%8] = 0x00000000;
225 		bogus[(1+i)%8] = 0x55555555;
226 		bogus[(2+i)%8] = 0xFFFFFFFF;
227 		bogus[(3+i)%8] = 0xAAAAAAAA;
228 		bogus[(4+i)%8] = 0x33333333;
229 		bogus[(5+i)%8] = 0xCCCCCCCC;
230 		bogus[(6+i)%8] = 0xCCCCCCCC;
231 		bogus[(7+i)%8] = 0x33333333;
232 		wmb();
233 		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
234 		mb();
235 		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
236 			return PSURGE_DUAL;
237 	}
238 	return type;
239 }
240 
241 static void __init psurge_quad_init(void)
242 {
243 	int procbits;
244 
245 	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
246 	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
247 	if (psurge_type == PSURGE_QUAD_ICEGRASS)
248 		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
249 	else
250 		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
251 	mdelay(33);
252 	out_8(psurge_sec_intr, ~0);
253 	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
254 	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
255 	if (psurge_type != PSURGE_QUAD_ICEGRASS)
256 		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
257 	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
258 	mdelay(33);
259 	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
260 	mdelay(33);
261 	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
262 	mdelay(33);
263 }
264 
265 static int __init smp_psurge_probe(void)
266 {
267 	int i, ncpus;
268 
269 	/* We don't do SMP on the PPC601 -- paulus */
270 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
271 		return 1;
272 
273 	/*
274 	 * The powersurge cpu board can be used in the generation
275 	 * of powermacs that have a socket for an upgradeable cpu card,
276 	 * including the 7500, 8500, 9500, 9600.
277 	 * The device tree doesn't tell you if you have 2 cpus because
278 	 * OF doesn't know anything about the 2nd processor.
279 	 * Instead we look for magic bits in magic registers,
280 	 * in the hammerhead memory controller in the case of the
281 	 * dual-cpu powersurge board.  -- paulus.
282 	 */
283 	if (find_devices("hammerhead") == NULL)
284 		return 1;
285 
286 	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
287 	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
288 	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
289 
290 	psurge_type = psurge_quad_probe();
291 	if (psurge_type != PSURGE_DUAL) {
292 		psurge_quad_init();
293 		/* All released cards using this HW design have 4 CPUs */
294 		ncpus = 4;
295 	} else {
296 		iounmap(quad_base);
297 		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
298 			/* not a dual-cpu card */
299 			iounmap(hhead_base);
300 			psurge_type = PSURGE_NONE;
301 			return 1;
302 		}
303 		ncpus = 2;
304 	}
305 
306 	psurge_start = ioremap(PSURGE_START, 4);
307 	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
308 
309 	/*
310 	 * This is necessary because OF doesn't know about the
311 	 * secondary cpu(s), and thus there aren't nodes in the
312 	 * device tree for them, and smp_setup_cpu_maps hasn't
313 	 * set their bits in cpu_possible_map and cpu_present_map.
314 	 */
315 	if (ncpus > NR_CPUS)
316 		ncpus = NR_CPUS;
317 	for (i = 1; i < ncpus ; ++i) {
318 		cpu_set(i, cpu_present_map);
319 		cpu_set(i, cpu_possible_map);
320 		set_hard_smp_processor_id(i, i);
321 	}
322 
323 	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
324 
325 	return ncpus;
326 }
327 
328 static void __init smp_psurge_kick_cpu(int nr)
329 {
330 	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
331 	unsigned long a;
332 
333 	/* may need to flush here if secondary bats aren't setup */
334 	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
335 		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
336 	asm volatile("sync");
337 
338 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
339 
340 	out_be32(psurge_start, start);
341 	mb();
342 
343 	psurge_set_ipi(nr);
344 	udelay(10);
345 	psurge_clr_ipi(nr);
346 
347 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
348 }
349 
350 /*
351  * With the dual-cpu powersurge board, the decrementers and timebases
352  * of both cpus are frozen after the secondary cpu is started up,
353  * until we give the secondary cpu another interrupt.  This routine
354  * uses this to get the timebases synchronized.
355  *  -- paulus.
356  */
357 static void __init psurge_dual_sync_tb(int cpu_nr)
358 {
359 	int t;
360 
361 	set_dec(tb_ticks_per_jiffy);
362 	/* XXX fixme */
363 	set_tb(0, 0);
364 	last_jiffy_stamp(cpu_nr) = 0;
365 
366 	if (cpu_nr > 0) {
367 		mb();
368 		sec_tb_reset = 1;
369 		return;
370 	}
371 
372 	/* wait for the secondary to have reset its TB before proceeding */
373 	for (t = 10000000; t > 0 && !sec_tb_reset; --t)
374 		;
375 
376 	/* now interrupt the secondary, starting both TBs */
377 	psurge_set_ipi(1);
378 }
379 
380 static struct irqaction psurge_irqaction = {
381 	.handler = psurge_primary_intr,
382 	.flags = SA_INTERRUPT,
383 	.mask = CPU_MASK_NONE,
384 	.name = "primary IPI",
385 };
386 
387 static void __init smp_psurge_setup_cpu(int cpu_nr)
388 {
389 
390 	if (cpu_nr == 0) {
391 		/* If we failed to start the second CPU, we should still
392 		 * send it an IPI to start the timebase & DEC or we might
393 		 * have them stuck.
394 		 */
395 		if (num_online_cpus() < 2) {
396 			if (psurge_type == PSURGE_DUAL)
397 				psurge_set_ipi(1);
398 			return;
399 		}
400 		/* reset the entry point so if we get another intr we won't
401 		 * try to startup again */
402 		out_be32(psurge_start, 0x100);
403 		if (setup_irq(30, &psurge_irqaction))
404 			printk(KERN_ERR "Couldn't get primary IPI interrupt");
405 	}
406 
407 	if (psurge_type == PSURGE_DUAL)
408 		psurge_dual_sync_tb(cpu_nr);
409 }
410 
411 void __init smp_psurge_take_timebase(void)
412 {
413 	/* Dummy implementation */
414 }
415 
416 void __init smp_psurge_give_timebase(void)
417 {
418 	/* Dummy implementation */
419 }
420 
421 /* PowerSurge-style Macs */
422 struct smp_ops_t psurge_smp_ops = {
423 	.message_pass	= smp_psurge_message_pass,
424 	.probe		= smp_psurge_probe,
425 	.kick_cpu	= smp_psurge_kick_cpu,
426 	.setup_cpu	= smp_psurge_setup_cpu,
427 	.give_timebase	= smp_psurge_give_timebase,
428 	.take_timebase	= smp_psurge_take_timebase,
429 };
430 #endif /* CONFIG_PPC32 - actually powersurge support */
431 
432 #ifdef CONFIG_PPC64
433 /*
434  * G5s enable/disable the timebase via an i2c-connected clock chip.
435  */
436 static struct device_node *pmac_tb_clock_chip_host;
437 static u8 pmac_tb_pulsar_addr;
438 static void (*pmac_tb_freeze)(int freeze);
439 static DEFINE_SPINLOCK(timebase_lock);
440 static unsigned long timebase;
441 
442 static void smp_core99_cypress_tb_freeze(int freeze)
443 {
444 	u8 data;
445 	int rc;
446 
447 	/* Strangely, the device-tree says address is 0xd2, but darwin
448 	 * accesses 0xd0 ...
449 	 */
450 	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_combined);
451 	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
452 			       0xd0 | pmac_low_i2c_read,
453 			       0x81, &data, 1);
454 	if (rc != 0)
455 		goto bail;
456 
457 	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
458 
459        	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_stdsub);
460 	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
461 			       0xd0 | pmac_low_i2c_write,
462 			       0x81, &data, 1);
463 
464  bail:
465 	if (rc != 0) {
466 		printk("Cypress Timebase %s rc: %d\n",
467 		       freeze ? "freeze" : "unfreeze", rc);
468 		panic("Timebase freeze failed !\n");
469 	}
470 }
471 
472 
473 static void smp_core99_pulsar_tb_freeze(int freeze)
474 {
475 	u8 data;
476 	int rc;
477 
478 	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_combined);
479 	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
480 			       pmac_tb_pulsar_addr | pmac_low_i2c_read,
481 			       0x2e, &data, 1);
482 	if (rc != 0)
483 		goto bail;
484 
485 	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
486 
487 	pmac_low_i2c_setmode(pmac_tb_clock_chip_host, pmac_low_i2c_mode_stdsub);
488 	rc = pmac_low_i2c_xfer(pmac_tb_clock_chip_host,
489 			       pmac_tb_pulsar_addr | pmac_low_i2c_write,
490 			       0x2e, &data, 1);
491  bail:
492 	if (rc != 0) {
493 		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
494 		       freeze ? "freeze" : "unfreeze", rc);
495 		panic("Timebase freeze failed !\n");
496 	}
497 }
498 
499 
500 static void smp_core99_give_timebase(void)
501 {
502 	/* Open i2c bus for synchronous access */
503 	if (pmac_low_i2c_open(pmac_tb_clock_chip_host, 0))
504 		panic("Can't open i2c for TB sync !\n");
505 
506 	spin_lock(&timebase_lock);
507 	(*pmac_tb_freeze)(1);
508 	mb();
509 	timebase = get_tb();
510 	spin_unlock(&timebase_lock);
511 
512 	while (timebase)
513 		barrier();
514 
515 	spin_lock(&timebase_lock);
516 	(*pmac_tb_freeze)(0);
517 	spin_unlock(&timebase_lock);
518 
519 	/* Close i2c bus */
520 	pmac_low_i2c_close(pmac_tb_clock_chip_host);
521 }
522 
523 
524 static void __devinit smp_core99_take_timebase(void)
525 {
526 	while (!timebase)
527 		barrier();
528 	spin_lock(&timebase_lock);
529 	set_tb(timebase >> 32, timebase & 0xffffffff);
530 	timebase = 0;
531 	spin_unlock(&timebase_lock);
532 }
533 
534 static void __init smp_core99_setup(int ncpus)
535 {
536 	struct device_node *cc = NULL;
537 	struct device_node *p;
538 	u32 *reg;
539 	int ok;
540 
541 	/* HW sync only on these platforms */
542 	if (!machine_is_compatible("PowerMac7,2") &&
543 	    !machine_is_compatible("PowerMac7,3") &&
544 	    !machine_is_compatible("RackMac3,1"))
545 		return;
546 
547 	/* Look for the clock chip */
548 	while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
549 		p = of_get_parent(cc);
550 		ok = p && device_is_compatible(p, "uni-n-i2c");
551 		of_node_put(p);
552 		if (!ok)
553 			continue;
554 
555 		reg = (u32 *)get_property(cc, "reg", NULL);
556 		if (reg == NULL)
557 			continue;
558 
559 		switch (*reg) {
560 		case 0xd2:
561 			if (device_is_compatible(cc, "pulsar-legacy-slewing")) {
562 				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
563 				pmac_tb_pulsar_addr = 0xd2;
564 				printk(KERN_INFO "Timebase clock is Pulsar chip\n");
565 			} else if (device_is_compatible(cc, "cy28508")) {
566 				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
567 				printk(KERN_INFO "Timebase clock is Cypress chip\n");
568 			}
569 			break;
570 		case 0xd4:
571 			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
572 			pmac_tb_pulsar_addr = 0xd4;
573 			printk(KERN_INFO "Timebase clock is Pulsar chip\n");
574 			break;
575 		}
576 		if (pmac_tb_freeze != NULL) {
577 			pmac_tb_clock_chip_host = of_get_parent(cc);
578 			of_node_put(cc);
579 			break;
580 		}
581 	}
582 	if (pmac_tb_freeze == NULL) {
583 		smp_ops->give_timebase = smp_generic_give_timebase;
584 		smp_ops->take_timebase = smp_generic_take_timebase;
585 	}
586 }
587 
588 /* nothing to do here, caches are already set up by service processor */
589 static inline void __devinit core99_init_caches(int cpu)
590 {
591 }
592 
593 #else /* CONFIG_PPC64 */
594 
595 /*
596  * SMP G4 powermacs use a GPIO to enable/disable the timebase.
597  */
598 
599 static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */
600 
601 static unsigned int pri_tb_hi, pri_tb_lo;
602 static unsigned int pri_tb_stamp;
603 
604 /* not __init, called in sleep/wakeup code */
605 void smp_core99_give_timebase(void)
606 {
607 	unsigned long flags;
608 	unsigned int t;
609 
610 	/* wait for the secondary to be in take_timebase */
611 	for (t = 100000; t > 0 && !sec_tb_reset; --t)
612 		udelay(10);
613 	if (!sec_tb_reset) {
614 		printk(KERN_WARNING "Timeout waiting sync on second CPU\n");
615 		return;
616 	}
617 
618 	/* freeze the timebase and read it */
619 	/* disable interrupts so the timebase is disabled for the
620 	   shortest possible time */
621 	local_irq_save(flags);
622 	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
623 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
624 	mb();
625 	pri_tb_hi = get_tbu();
626 	pri_tb_lo = get_tbl();
627 	pri_tb_stamp = last_jiffy_stamp(smp_processor_id());
628 	mb();
629 
630 	/* tell the secondary we're ready */
631 	sec_tb_reset = 2;
632 	mb();
633 
634 	/* wait for the secondary to have taken it */
635 	/* note: can't use udelay here, since it needs the timebase running */
636 	for (t = 10000000; t > 0 && sec_tb_reset; --t)
637 		barrier();
638 	if (sec_tb_reset)
639 		/* XXX BUG_ON here? */
640 		printk(KERN_WARNING "Timeout waiting sync(2) on second CPU\n");
641 
642 	/* Now, restart the timebase by leaving the GPIO to an open collector */
643        	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
644         pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
645 	local_irq_restore(flags);
646 }
647 
648 /* not __init, called in sleep/wakeup code */
649 void smp_core99_take_timebase(void)
650 {
651 	unsigned long flags;
652 
653 	/* tell the primary we're here */
654 	sec_tb_reset = 1;
655 	mb();
656 
657 	/* wait for the primary to set pri_tb_hi/lo */
658 	while (sec_tb_reset < 2)
659 		mb();
660 
661 	/* set our stuff the same as the primary */
662 	local_irq_save(flags);
663 	set_dec(1);
664 	set_tb(pri_tb_hi, pri_tb_lo);
665 	last_jiffy_stamp(smp_processor_id()) = pri_tb_stamp;
666 	mb();
667 
668 	/* tell the primary we're done */
669        	sec_tb_reset = 0;
670 	mb();
671 	local_irq_restore(flags);
672 }
673 
674 /* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
675 volatile static long int core99_l2_cache;
676 volatile static long int core99_l3_cache;
677 
678 static void __devinit core99_init_caches(int cpu)
679 {
680 	if (!cpu_has_feature(CPU_FTR_L2CR))
681 		return;
682 
683 	if (cpu == 0) {
684 		core99_l2_cache = _get_L2CR();
685 		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
686 	} else {
687 		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
688 		_set_L2CR(0);
689 		_set_L2CR(core99_l2_cache);
690 		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
691 	}
692 
693 	if (!cpu_has_feature(CPU_FTR_L3CR))
694 		return;
695 
696 	if (cpu == 0){
697 		core99_l3_cache = _get_L3CR();
698 		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
699 	} else {
700 		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
701 		_set_L3CR(0);
702 		_set_L3CR(core99_l3_cache);
703 		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
704 	}
705 }
706 
707 static void __init smp_core99_setup(int ncpus)
708 {
709 	struct device_node *cpu;
710 	u32 *tbprop = NULL;
711 	int i;
712 
713 	core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
714 	cpu = of_find_node_by_type(NULL, "cpu");
715 	if (cpu != NULL) {
716 		tbprop = (u32 *)get_property(cpu, "timebase-enable", NULL);
717 		if (tbprop)
718 			core99_tb_gpio = *tbprop;
719 		of_node_put(cpu);
720 	}
721 
722 	/* XXX should get this from reg properties */
723 	for (i = 1; i < ncpus; ++i)
724 		smp_hw_index[i] = i;
725 	powersave_nap = 0;
726 }
727 #endif
728 
729 static int __init smp_core99_probe(void)
730 {
731 	struct device_node *cpus;
732 	int ncpus = 0;
733 
734 	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
735 
736 	/* Count CPUs in the device-tree */
737        	for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
738 	       	++ncpus;
739 
740 	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
741 
742 	/* Nothing more to do if less than 2 of them */
743 	if (ncpus <= 1)
744 		return 1;
745 
746 	smp_core99_setup(ncpus);
747 	mpic_request_ipis();
748 	core99_init_caches(0);
749 
750 	return ncpus;
751 }
752 
753 static void __devinit smp_core99_kick_cpu(int nr)
754 {
755 	unsigned int save_vector;
756 	unsigned long new_vector;
757 	unsigned long flags;
758 	volatile unsigned int *vector
759 		 = ((volatile unsigned int *)(KERNELBASE+0x100));
760 
761 	if (nr < 0 || nr > 3)
762 		return;
763 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu", 0x346);
764 
765 	local_irq_save(flags);
766 	local_irq_disable();
767 
768 	/* Save reset vector */
769 	save_vector = *vector;
770 
771 	/* Setup fake reset vector that does
772 	 *   b __secondary_start_pmac_0 + nr*8 - KERNELBASE
773 	 */
774 	new_vector = (unsigned long) __secondary_start_pmac_0 + nr * 8;
775 	*vector = 0x48000002 + new_vector - KERNELBASE;
776 
777 	/* flush data cache and inval instruction cache */
778 	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
779 
780 	/* Put some life in our friend */
781 	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
782 
783 	/* FIXME: We wait a bit for the CPU to take the exception, I should
784 	 * instead wait for the entry code to set something for me. Well,
785 	 * ideally, all that crap will be done in prom.c and the CPU left
786 	 * in a RAM-based wait loop like CHRP.
787 	 */
788 	mdelay(1);
789 
790 	/* Restore our exception vector */
791 	*vector = save_vector;
792 	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
793 
794 	local_irq_restore(flags);
795 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
796 }
797 
798 static void __devinit smp_core99_setup_cpu(int cpu_nr)
799 {
800 	/* Setup L2/L3 */
801 	if (cpu_nr != 0)
802 		core99_init_caches(cpu_nr);
803 
804 	/* Setup openpic */
805 	mpic_setup_this_cpu();
806 
807 	if (cpu_nr == 0) {
808 #ifdef CONFIG_POWER4
809 		extern void g5_phy_disable_cpu1(void);
810 
811 		/* If we didn't start the second CPU, we must take
812 		 * it off the bus
813 		 */
814 		if (machine_is_compatible("MacRISC4") &&
815 		    num_online_cpus() < 2)
816 			g5_phy_disable_cpu1();
817 #endif /* CONFIG_POWER4 */
818 		if (ppc_md.progress) ppc_md.progress("core99_setup_cpu 0 done", 0x349);
819 	}
820 }
821 
822 
823 #if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
824 
825 int smp_core99_cpu_disable(void)
826 {
827 	cpu_clear(smp_processor_id(), cpu_online_map);
828 
829 	/* XXX reset cpu affinity here */
830 	mpic_cpu_set_priority(0xf);
831 	asm volatile("mtdec %0" : : "r" (0x7fffffff));
832 	mb();
833 	udelay(20);
834 	asm volatile("mtdec %0" : : "r" (0x7fffffff));
835 	return 0;
836 }
837 
838 extern void low_cpu_die(void) __attribute__((noreturn)); /* in sleep.S */
839 static int cpu_dead[NR_CPUS];
840 
841 void cpu_die(void)
842 {
843 	local_irq_disable();
844 	cpu_dead[smp_processor_id()] = 1;
845 	mb();
846 	low_cpu_die();
847 }
848 
849 void smp_core99_cpu_die(unsigned int cpu)
850 {
851 	int timeout;
852 
853 	timeout = 1000;
854 	while (!cpu_dead[cpu]) {
855 		if (--timeout == 0) {
856 			printk("CPU %u refused to die!\n", cpu);
857 			break;
858 		}
859 		msleep(1);
860 	}
861 	cpu_dead[cpu] = 0;
862 }
863 
864 #endif
865 
866 /* Core99 Macs (dual G4s and G5s) */
867 struct smp_ops_t core99_smp_ops = {
868 	.message_pass	= smp_mpic_message_pass,
869 	.probe		= smp_core99_probe,
870 	.kick_cpu	= smp_core99_kick_cpu,
871 	.setup_cpu	= smp_core99_setup_cpu,
872 	.give_timebase	= smp_core99_give_timebase,
873 	.take_timebase	= smp_core99_take_timebase,
874 #if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC32)
875 	.cpu_disable	= smp_core99_cpu_disable,
876 	.cpu_die	= smp_core99_cpu_die,
877 #endif
878 };
879